Foldable push cart

Abstract

The present invention relates to a foldable push-pull cart, comprising an upper U-shaped horizontal tube A, an upper U-shaped horizontal tube B, a lower U-shaped horizontal tube A, a lower U-shaped horizontal tube B, a middle U-shaped horizontal tube, a vertical U-shaped tube, an upper side push-pull tube, a lower side push-pull tube, an upper longitudinal tube A, an upper longitudinal tube B, a lower longitudinal tube A, a lower longitudinal tube B, a middle longitudinal tube, a middle transverse tube, a vertical tube, an upper support, a lower support, a transverse horizontal tube A, a transverse horizontal tube B, a transverse cross tube, a rigid hinge device, etc. More than ten folding methods are adopted, such as a side-fixed connecting tube folding device, a side-sliding folding device, a middle sliding folding device, a side-fixed connecting tube middle vertical tube folding device, a cross folding device, a four-corner pull-out rod folding device, a transverse composite cross folding device, etc. The rigid hinge device is configured so that the foldable push-pull cart can be smoothly folded into a sheet or stick shape, has high system rigidity when unfolded, and has a small size after folding, which is convenient to carry and place.

Description

Technical Field

[0001] The present invention relates to furniture products, belonging to indoor and outdoor transportation products, in particular to a push or pull cart which can be conveniently folded and unfolded. Background Art

[0002] Among the existing push-pull carts for indoor and outdoor transportation, the vast majority are fixed as a whole and cannot be folded and unfolded. They take up a relatively large space when placed. Among the current foldable tourism and leisure products, although there are a few foldable push-pull carts, they are all non-rigidly hinged and have complicated folding and unfolding structures. Their folding principles and folding methods make the connection rigidity of the unfolded push-pull cart poor and the carrying capacity insufficient. For this reason, people hope to have a type of foldable push-pull cart with simple structure, low production cost, light weight, easy to carry, good system hinge rigidity after unfolding, small size after folding, which can be placed and used indoors and outdoors. Summary of the Invention

[0003] The purpose of the present invention is to provide a type of foldable push-pull cart, which adopts a variety of folding and unfolding principles and rigid hinged structures with different structures, so that various fixed push-pull carts can be folded and unfolded at will, that is, the volume is small when folded, the rigidity is strong when unfolded, the structure is simple, the weight is light, and it is easy to carry.

[0004] The object of the present invention is to be achieved by the following measures:

[0005] A foldable push-pull cart comprises: an upper U-shaped horizontal tube A (1), an upper U-shaped horizontal tube B (2), a lower U-shaped horizontal tube A (3), a lower U-shaped horizontal tube B (4), a middle U-shaped horizontal tube (5), a vertical U-shaped tube (6) or a two-layer vertical standpipe device (40) or a multi-layer vertical standpipe device (30), a vertical tube A (7), a vertical tube B (8), a support (25), a push-pull tube (26), a rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), a side-fixed connecting tube folding device (27, 41, 42, 43, 44, 45), a side-fixed connecting tube middle vertical tube folding device (7, 8, 41, 43, 44), a side-sliding folding device (9, 10, 13 , 25, 26, 27, 29, 44), a middle sliding folding device (7, 8, 11, 12, 29), a side rotating folding device (9, 10, 27, 33, 34, 36), a cross folding device (27, 44, 77), a cross tube vertical tube folding device (7, 8, 27, 44, 77), a middle vertical tube side sliding folding device (7, 8, 9, 13, 27, 44), a side sliding hinged cross folding device (7, 8, 13, 44, 48), a fixed handle (23), a handle device A (24), a flexible fabric (28), a panel (21), a universal wheel (22), and further comprising: a transverse tube (20), an eccentric hinge (35), a supporting sleeve (37), a braided ribbon (46), characterized in that, the upper The U-shaped horizontal tube A (1) is hinged to the upper U-shaped horizontal tube B (2) via a rigid hinge device, the lower U-shaped horizontal tube A (3) is hinged to the lower U-shaped horizontal tube B (4) via a rigid hinge device, and the middle U-shaped horizontal tube A (5) is hinged to each other or to a rigid hinge device, or not hinged, and their two sides are hinged to the vertical U-shaped tube (6), or to the two-layer end vertical tube device (40), or to the multi-layer end vertical tube device (30). According to different folding methods, on the longitudinal surface of the foldable push-pull cart, either a side-fixed connecting tube folding device, or a side-fixed connecting tube middle vertical tube folding device, or a side-sliding folding device, or a middle sliding folding device, or a side-rotating folding device, or a cross-folding device is installed. The device is provided, or a cross-tube vertical tube folding device is installed, or a middle vertical tube side sliding folding device is installed, or a side sliding hinged cross-folding device is installed. According to different foldable push-pull carts, a fixed handle (23) or a handle device A (24) is installed. The universal wheel (22) is fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device. The lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged with the vertical U-shaped tube, the two-layer end vertical tube device, and the multi-layer end vertical tube device, or is directly hinged or hinged via an eccentric hinge (35). For a multi-layer foldable push-pull cart, the middle U-shaped horizontal tube (5) is directly hinged with the vertical U-shaped tubes on both sides.Alternatively, one side is directly hinged and the other side is hinged by sliding through a support sleeve (37). In this way, the support (25) and the middle U-shaped horizontal tube (5) can be pushed by the push-pull tube (26) on the directly hinged side to synchronously rotate the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B and the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B upwards, and then hinged through the rigid hinge device, driving the middle U-shaped horizontal tube (5) on the other side to rotate and slide. The transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. Foldable push-pull carts for different purposes can use either a hard panel (21) or a flexible fabric (28). In order to improve the bearing capacity of the foldable push-pull cart, either a flexible fabric is configured and a braided ribbon (46) is also configured at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4).

[0006] A further solution is: the above-mentioned side fixed connecting tube folding device (27, 41, 42, 43, 44, 45) includes: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), a horizontal tube hinge support (44), a hinge (45), one end of the connecting rod A (41) is directly hinged to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2), or is fixed to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2) through a water pipe. The horizontal tube hinge support (44) is hinged, and the other end is hinged to the vertical U-shaped tube (6) on the opposite side or hinged via the vertical tube hinge support (43) fixed on the vertical U-shaped tube. The upper end of the connecting rod B (42) is hinged to the middle part of the connecting rod A (41) or directly hinged or hinged via a hinge (45). The lower end of the connecting rod B is hinged to the lower U-shaped horizontal tube A (3) or the lower U-shaped horizontal tube B (4) on the same side or hinged via a b-shaped hinge, thereby realizing the folding and unfolding of the foldable push-pull cart. A vertical tube folding device (7, 8, 41, 43, 44) in a fixed connecting tube comprises: a vertical tube belt A (7), a vertical tube belt B (8), a connecting rod A (41), a vertical tube hinge support (43), and a horizontal tube hinge support (44). One end of the connecting rod A (41) is directly hinged to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2), or is hinged to it via a b-shaped hinge, or is hinged to the horizontal tube hinge support (44) fixed on the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, and the other end is hinged to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2). It is hinged to the vertical U-shaped tube (6) on the opposite side either directly, or through a vertical tube hinge support (43) fixed on the vertical U-shaped tube, or through a b-shaped hinge. One end of the vertical tube belt A (7) or the vertical tube belt B (8) is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the hinge point of the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) or the middle hinge point of the two middle U-shaped horizontal tubes, so that the foldable push-pull cart can be folded and unfolded.The above-mentioned sliding and folding device (9, 10, 13, 25, 26, 27, 29, 44) includes: an upper side push-pull tube (9), a lower side push-pull tube (10), a side sliding sleeve (13), a b-shaped hinge (27), a limiter (29), or includes: a support (25), a push-pull tube (26), a horizontal tube hinge support (44), one end of the upper side push-pull tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via a b-shaped hinge, or via a horizontal tube hinge support, and the other end is connected to the device on the vertical U-shaped tube (6), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30). The side sliding sleeve (13) is hinged, one end of the lower side push-pull tube is hinged to the side sliding sleeve installed on the vertical U-shaped tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30), and the other end is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or hinged to them via a b-shaped hinge, in the middle of the upper side push-pull tube (9) or the lower side push-pull tube (10), or hinged to the push-pull tube (26), the other end of the push-pull tube is directly hinged to the middle U-shaped horizontal tube (5), or hinged to it via a support (25), so that the folding and unfolding of the foldable push-pull cart can be realized, and the limit member (29) is installed A vertical U-shaped tube, or a two-layer vertical riser device (40), or a middle part of a multi-layer vertical riser device (30), limits the maximum sliding position of the side sliding sleeve; the above-mentioned middle sliding folding device (7, 8, 11, 12, 29) includes: a vertical tube belt A (7), a vertical tube belt B (8), a middle push-pull tube (11), a middle sliding sleeve (12), a limiter (29), one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. It is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, and the other end is hinged to the middle hinge point of the two middle U-shaped horizontal tubes. The middle sliding sleeve (12) is inserted into the vertical tube belt A or the vertical tube belt B and can slide thereon. One end of the symmetrically distributed middle push-pull tube (11) is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the middle sliding sleeve, so that the foldable push-pull cart can be folded and unfolded. The limiter (29) is installed on the vertical tube belt A or the vertical tube belt B to limit the maximum sliding position of the middle sliding sleeve.The above-mentioned rotating folding device (9, 10, 27, 33, 34, 36) comprises: an upper side push-pull tube (9), a lower side push-pull tube (10), a b-shaped hinge (27), a rotating rod (33), a limit block (34), and a connecting piece (36). One end of the upper side push-pull tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or hinged to them via a b-shaped hinge, and the other end is hinged to one end of the rotating rod (33). The other end of the rotating rod is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B. One end is hinged to the vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30); one end of the lower side push-pull tube (10) is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B or hinged to them via a b-shaped hinge; the other end is provided with a limit block (34) hinged to the upper side push-pull tube side hinge point at the same point or at a different point; when the foldable push-pull cart is unfolded, the limit block can be closely attached to the vertical U-shaped tube (6), or two layers of vertical riser device (40). The invention relates to a multi-layer vertical riser device (40) or a multi-layer vertical riser device (30), thereby realizing the folding and limited expansion of the foldable push-pull cart; the above-mentioned cross-folding device (27, 44, 77) comprises: a b-shaped hinge (27), a horizontal tube hinge support (44), and a longitudinal cross tube (77); the longitudinal cross tube (77) is arranged symmetrically and crosswise in the longitudinal two side planes, or is arranged crosswise in the longitudinal one side plane, or is arranged single in the longitudinal two side planes respectively; one end of the longitudinal cross tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via the horizontal tube hinge support (44) or via the b-shaped hinge; the other end is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or is hinged to them via the b-shaped hinge; the middle parts of the symmetrically cross-arranged longitudinal cross tubes do not need to be hinged to each other, thereby realizing the folding and expansion of the foldable push-pull cart;The above-mentioned cross-tube vertical tube folding device (7, 8, 27, 44, 77) comprises: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge support (44), a longitudinal cross tube (77), the longitudinal cross tube (77) being arranged in a symmetrical projection or mirror image cross-arrangement in parallel planes on both sides of the longitudinal direction, or being arranged in a single oblique direction in a plane on one side of the longitudinal direction, one end of the longitudinal cross tube being directly hinged to the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, or being hinged to it via the horizontal tube hinge support (44) or via the b-shaped hinge, and the other end being hinged to the lower U-shaped horizontal tube The horizontal tube A or the lower U-shaped horizontal tube B is directly hinged or hinged with it through a b-shaped hinge. The middle parts of the symmetrically arranged longitudinal cross tubes do not need to be hinged to each other. The upper end of the vertical tube belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the lower end of the vertical tube belt B is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. After the two ends of the vertical tube belt A are hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B and the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, the middle part or the two middle U-shaped horizontal tubes ( 5) is hinged at the middle hinge point, thereby realizing the folding and unfolding of the foldable push-pull cart; the above-mentioned middle vertical tube side sliding folding device (7, 8, 9, 13, 27, 29, 44) comprises: a vertical tube belt A (7), a vertical tube belt B (8), an upper side push-pull tube (9), a side sliding sleeve (13), a b-shaped hinge (27), a limiter (29), a horizontal tube hinge support (44), one end of the upper side push-pull tube (9) is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via the horizontal tube hinge support (44) or via the b-shaped hinge, and the other end is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B. The side sliding sleeve (13) is hinged on the vertical U-shaped tube (6), or the two-layer vertical riser tube device (40), or the multi-layer vertical riser tube device (30); the limiter (29) is installed in the middle of the vertical U-shaped tube, or the two-layer vertical riser tube device (40), or the multi-layer vertical riser tube device (30) to limit the maximum sliding position of the side sliding sleeve; the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge points of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B; thereby, the folding and unfolding of the foldable push-pull cart can be realized;The above-mentioned side sliding hinged cross folding device (7, 8, 13, 27, 44, 48) comprises: a vertical tube belt A (7), a vertical tube belt B (8), a side sliding sleeve (13), a b-shaped hinge (27), a horizontal tube hinge support (44), a hinged cross tube (48), one end of the hinged cross tube (48) is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via the horizontal tube hinge support (44) or via the b-shaped hinge, and the other end is hinged to the vertical U-shaped horizontal tube. The side sliding sleeve (13) on the tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30) is hinged, and the two hinged cross tubes on the same side are hinged to each other at the middle of the tube. The two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge points of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. Alternatively, the foldable push-pull cart can be folded and unfolded without installing the vertical tube belt A or the vertical tube belt B.

[0007] A further solution is that the multi-layer end vertical pipe device (30) is composed of a segmented pipe (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, and the middle connecting piece is either fixed to the other end of the upper and lower segmented pipes, or to the upper and lower segments. The other end of the segmented pipe is fixed at the same time as the two ends of the segmented pipe in the middle of the fourth layer or more are fixed. The semicircular sleeve is symmetrically installed and fixed by a limit pin on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the U-shaped bottom edges of the middle U-shaped horizontal pipe after being hinged by the rigid hinge device. The upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, thereby forming a rigidly connected multi-layer end straight pipe device (30). The semicircular sleeve The flanges (30.7) at both ends can prevent the lateral movement of the multi-layer end vertical pipe device, and at the same time, each U-shaped horizontal pipe can also rotate around each connecting piece; the above-mentioned two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeves are symmetrically installed and The upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, which are hinged via a rigid hinge device, are fixed by a limit pin. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, thereby forming a rigidly connected two-layer end vertical tube device (40). The semicircular sleeve has flanges (30.7) at both ends to prevent the two-layer end vertical tube device from lateral movement. At the same time, each U-shaped horizontal tube can also rotate around each connecting piece.

[0008] A foldable push-pull cart comprises: an upper longitudinal tube A (50), an upper longitudinal tube B (51), a lower longitudinal tube A (52), a lower longitudinal tube B (53), a middle longitudinal tube (54), a middle transverse tube (55), a vertical tube (56), an upper support (57), a lower support (58), a middle support (59), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a locking piece (65), a transverse hinge (66), a wheel support (67), a support (25), a push-pull tube (26), a rigid hinge device (17, 18, 19, 47, 49, 78, 79), a sliding folding device B (9, 10, 25, 26, 27, 29, 44, 80), a side fixed connecting tube folding device (27, 41, 42, 43, 44, 45), vertical tube folding device (7, 8, 41, 43, 44) for fixing the connecting tube, middle sliding folding device (7, 8, 11, 12, 29), rotating folding device (9, 10, 27, 33, 34, 36), cross folding device (27, 44, 77), cross tube vertical tube folding device (7, 8, 27, 44, 77), middle vertical tube sliding folding device (7, 8, 27, 29, 44, 64, 71, 72, 73, 74, 75, 80), sliding hinged cross folding device B (7, 8, 27, 44, 48, 80), sliding folding device C (9, 10, 25, 26, 27, 29, 44, 80, 81, 82), Four-corner pull-out rod folding device (27, 70, 71, 72, 73, 74, 75), transverse composite cross-folding device (60, 61, 62, 63, 78, 79, 80), transverse side sliding cross-folding device (44, 80, 81, 82, 83), fixed handle (23), handle device B (38), flexible fabric (28), universal wheel (22), also including: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device, the transverse horizontal tube A (81) and the transverse horizontal tube B ( 82) is hinged by a rigid hinge device. After the rigid hinge is rigidly hinged, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or are hinged to the upper support (57) and the lower support (57) fixed on the vertical tube (56). For multi-layer foldable push-pull carts with more than three layers, the middle longitudinal tubes and the middle transverse tubes are hinged to each other by a rigid hinge device in pairs, or are not hinged. The other ends of the two middle longitudinal tubes and the middle transverse tubes are hinged to the vertical tube (56) in the middle or directly, or are hinged to it through the middle support (59) fixed on the vertical tube (56). According to the different folding principles and folding methods, a sliding folding device B or a fixed tube folding device is installed on the longitudinal surface of the foldable push-pull cart.Or install a side-fixed connecting pipe middle vertical pipe folding device, or install a middle sliding folding device, or install a side-rotating folding device, or install a cross-folding device, or install a cross-tube vertical pipe folding device, or install a middle vertical pipe side-drawing sliding folding device (7, 8, 27, 29, 44, 64, 72, 73, 74, 75, 80), or install a side-sliding hinged cross-folding device B, on the transverse surfaces of both ends of the foldable push-pull cart, or install a side-sliding folding device C (9, 10, 25, 26, 27, 29, 80, 81, 82), or install a four-corner draw-rod folding device (27, 70, 71, 72, 73, 74, 75) or install A transverse composite cross-folding device (60, 61, 62, 63, 78, 79) or a transverse side sliding cross-folding device (44, 80, 81, 82, 83) is provided. Depending on the type of foldable push-pull cart, a fixed handle (23) or a handle device B (38) is provided. The universal wheel (22) is fixed to the lower end of the vertical tube (56) via a wheel support (67). The upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), or the transverse horizontal tube A (81) and the transverse horizontal tube B (82) are directly hinged to the vertical tube (56) or hinged via an eccentric hinge (35). Through the hinge connection with the upper support (57) and the lower support (58) fixed at both ends of the vertical tube, for a multi-layer foldable push-pull cart, the middle longitudinal tube (54) and the middle transverse tube (55) are either hinged with the middle support (59) fixed in the middle of the vertical tube, or directly hinged with the four corner vertical tubes, or one side is hinged with the vertical tube and the other side is hinged by sliding through the support sleeve (37). In this way, the push-pull tube (26) on the directly hinged side can push the support (25) and drive the middle longitudinal tube (54) and the middle transverse tube (55) on the same corner side to rotate upward, and drive the middle longitudinal tube (54) and the middle transverse tube (55) on the other side to rotate and slide, and connect with the upper longitudinal tube B (51) and the lower longitudinal tube C (52). The longitudinal tube A (52), the lower longitudinal tube B (53) and the middle longitudinal tube (54) rotate upward synchronously. The foldable push-pull carts for different purposes may use flexible fabrics (28), braided ribbons (46), diagonally crossed ropes (84), steel ropes, or wire mesh. In order to further improve the carrying capacity and system rigidity of the foldable push-pull cart, flexible fabrics may be configured, or braided ribbons or wire ropes or wire mesh may be configured transversely on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or braided ribbons or wire ropes may be configured in the diagonally crossed direction of the foldable push-pull cart when viewed from above, so as to improve the system rigidity after unfolding.

[0009] A further solution is: the above-mentioned side sliding folding device B (9, 10, 25, 26, 27, 29, 44, 80) includes: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a b-shaped hinge (27), a limiter (29), or further includes: a support (25), a push-pull tube (26), a horizontal tube hinge support (44), on the longitudinal surface of the foldable push-pull vehicle, one end of the upper side push-pull tube (9) is directly hinged to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or is hinged to them via a b-shaped hinge, or is hinged to them via a horizontal tube hinge support, and the other end is hinged to the angular side sliding sleeve (80) installed on the vertical tube (56), and one end of the lower side push-pull tube is hinged to the device on the vertical tube (5 6) is hinged to the angular side sliding sleeve on the upper part, and the other end is hinged to the lower longitudinal tube A and the lower longitudinal tube B or directly, or hinged via a b-shaped hinge, or hinged to them via a horizontal tube hinge support. Similarly, on the transverse surface of the foldable push-pull cart, it can also be equivalent to a sliding folding device C and a sliding folding device B, that is: one end of the upper side push-pull tube (9) is hinged to the upper transverse horizontal tube A (81) and the upper transverse horizontal tube B (82) or directly, or hinged via a b-shaped hinge, or hinged to them via a horizontal tube hinge support, and the other end is hinged to the angular side sliding sleeve (80) installed on the vertical tube (56); one end of the lower side push-pull tube is hinged to the angular side sliding sleeve installed on the vertical tube (56), and the other end is hinged to the lower transverse horizontal tube A (81) and the lower transverse horizontal tube B (82). The horizontal tube B (82) is directly hinged, hinged via a b-shaped hinge, or hinged to the horizontal tube hinge support, and is hinged to the push-pull tube (26) in the middle of the upper push-pull tube (9) or the lower push-pull tube (10). The other end of the push-pull tube is directly hinged to the middle longitudinal tube (54) or hinged to the middle longitudinal tube (54) via a support (25), thereby realizing the folding and unfolding of the foldable push-pull vehicle. The limiter (29) is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve. The above-mentioned side fixed connecting tube folding device (27, 41, 42, 43, 44, 45) includes: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), and a horizontal tube hinge support (44). , hinge (45), one end of the connecting rod A (41) is directly hinged to the upper longitudinal tube A (50) or the upper longitudinal tube B (51), or is hinged via a b-shaped hinge, or is hinged via a horizontal tube hinge support (44) fixed on the upper longitudinal tube A (50) or the upper longitudinal tube B (51), and the other end is directly hinged to the vertical tube (56) on the opposite side, or is hinged via a vertical tube hinge support (43) fixed on the vertical tube, the upper end of the connecting rod B (42) is directly hinged to the middle part of the connecting rod A (41), or is hinged via a hinge (45), and the lower end of the connecting rod B is directly hinged to the lower longitudinal tube A (50) or the lower longitudinal tube B (51) on the same side, or is hinged thereto via a b-shaped hinge, thereby realizing the folding and unfolding of the foldable push-pull cart;The vertical tube folding device (7, 8, 41, 43, 44) in the above-mentioned side-fixed connecting tube comprises: a vertical tube belt A (7), a vertical tube belt B (8), a connecting rod A (41), a vertical tube hinge support (43), and a horizontal tube hinge support (44). One end of the connecting rod A (41) is directly hinged to the upper longitudinal tube A (50) or the upper longitudinal tube B (51), or is hinged to it via a b-shaped hinge, or is hinged to the horizontal tube hinge support (44) fixed on the upper longitudinal tube A (50) or the upper longitudinal tube B (51), and the other end is directly hinged to the vertical tube (56) on the opposite side, or is hinged to it via a vertical tube hinge support (43) fixed on the vertical U-shaped tube, or is hinged to it via a b-shaped hinge. The vertical tube belt A (7) or the vertical tube belt B (8) One end is hinged to the hinge point of the upper longitudinal tube A (50) and the upper longitudinal tube B (51), and the other end is hinged to the hinge point of the lower longitudinal tube A (52) and the lower longitudinal tube B (53) or the middle hinge point of the two middle longitudinal tubes (55), so that the foldable push-pull cart can be folded and unfolded; the above-mentioned middle sliding folding device (7, 8, 11, 12, 29) includes: vertical tube belt A (7), vertical tube belt B (8), middle push-pull tube (11), middle sliding sleeve (12), limiter (29), one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper longitudinal tube A and the upper longitudinal tube B, and the other end is hinged to the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, in the multi-layer foldable push-pull cart In the middle, the vertical tube belt A is hinged to the middle longitudinal tube (54) in pairs by a rigid hinge device, or is not hinged. The middle sliding sleeve (12) is inserted into the vertical tube belt A or the vertical tube belt B and can slide thereon. One end of the symmetrically distributed middle push-pull tube (11) is hinged to the lower longitudinal tube A and the lower longitudinal tube B, and the other end is hinged to the middle sliding sleeve, so that the foldable push-pull vehicle can be folded and unfolded. The limiter (29) is installed at the upper end of the vertical tube belt A or the vertical tube belt B to limit the maximum sliding position of the middle sliding sleeve. The above-mentioned rotating folding device (9, 10, 27, 33, 34, 36) includes: an upper push-pull tube (9), a lower push-pull tube (10), a b-shaped hinge (27), a rotating rod (33), a limiter (34), and a connecting piece. (36), one end of the upper push-pull tube is directly hinged to the upper longitudinal tube A and the upper longitudinal tube B, or hinged to them via a b-shaped hinge, and the other end is hinged to one end of the rotating rod (33), and the other end of the rotating rod is hinged to the vertical tube (56), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30). One end of the lower push-pull tube (10) is directly hinged to the lower longitudinal tube A and the lower longitudinal tube B, or hinged to them via a b-shaped hinge, and the other end is provided with a limit block (34) hinged to the upper push-pull tube side hinge point at the same point or at a different point. When the foldable push-pull cart is unfolded, the limit block can be in close contact with the vertical tube (56), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30), thereby realizing the folding and limited unfolding of the foldable push-pull cart;The cross-folding device (27, 44, 77) comprises: a b-shaped hinge (27), a horizontal tube hinge support (44), and a longitudinal cross tube (77). The longitudinal cross tube (77) is arranged symmetrically in a cross-shaped manner in the longitudinal two side planes, or is arranged cross-shaped in a longitudinal one side plane, or is arranged singly in the longitudinal two side planes. One end of the longitudinal cross tube is directly hinged to the upper longitudinal tube A and the upper longitudinal tube B, or is hinged to the upper longitudinal tube B via the horizontal tube hinge support (44) or via the b-shaped hinge. The vertical tube folding device (7, 8, 27, 44, 77) is hinged to the vertical tube and the vertical tube. The other end is hinged to the vertical tube and the vertical tube directly, or is hinged to the horizontal tube through a hinge support (44) or a b-shaped hinge. The middle parts of the symmetrically arranged longitudinal cross tubes do not need to be hinged to each other, thereby realizing the folding and unfolding of the foldable push-pull cart. The above-mentioned cross tube vertical tube folding device (7, 8, 27, 44, 77) includes: vertical tube belt A (7), vertical tube belt B (8), b-shaped hinge (27), horizontal tube hinge support (44), longitudinal The longitudinal cross tubes (77) are arranged in a symmetrical projection or mirror image cross pattern in parallel planes on both sides of the longitudinal direction, or arranged in a single oblique pattern in a plane on one side of the longitudinal direction. One end of the longitudinal cross tube is directly hinged to the upper longitudinal tube A or the upper longitudinal tube B, or is hinged to it through a horizontal tube hinge support (44) or a b-shaped hinge, and the other end is directly hinged to the lower longitudinal tube A or the lower longitudinal tube B, or is hinged to it through a b-shaped hinge. The symmetrically arranged longitudinal cross tubes do not need to be mutually hinged. Hinged, the upper end of the vertical tube belt B is hinged to the hinge point of the upper longitudinal tube A and the upper longitudinal tube B, the lower end of the vertical tube belt B is hinged to the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, and after the two ends of the vertical tube belt A are hinged to the hinge point of the upper longitudinal tube A and the upper longitudinal tube B and hinged to the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, the middle part is hinged to the middle hinge point of the two middle longitudinal tubes (54), thereby realizing the folding and unfolding of the foldable push-pull cart;The above-mentioned middle vertical tube side-drawing sliding folding device (7, 8, 27, 29, 44, 64, 71, 72, 73, 74, 75, 80) comprises: vertical tube belt A (7), vertical tube belt B (8), push-pull tube A (64), angular side sliding sleeve (80), B-shaped hinge (27), limiter (29), horizontal tube hinge support (44), and also comprises: push-pull tube B (71), push-pull tube C (72), draw-out sliding support (73), draw-out sliding sleeve (74), draw-out sliding tube (75), the two ends of vertical tube belt A or vertical tube belt B are respectively hinged to the hinge points of upper longitudinal tube A and upper longitudinal tube B, and the hinge points of lower longitudinal tube A and lower longitudinal tube B. One end of the push-pull tube (64) is hinged to the upper longitudinal tube A and the upper longitudinal tube B or the lower longitudinal tube A and the lower longitudinal tube B, or directly hinged, or hinged to them via a horizontal tube hinge support (44) or a b-shaped hinge, and the other end is hinged to an angular side sliding sleeve (80) installed on a vertical tube (56), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30), and a limiter (29) is installed in the middle of the vertical tube, or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30) to limit the maximum sliding position of the side sliding sleeve; one end of the push-pull tube B (71) or the push-pull tube C (72) is hinged to the lower longitudinal tube A and the lower longitudinal tube B, or directly hinged, or hinged to them via a horizontal tube hinge support (44) or a b-shaped hinge, and the other end is hinged to an angular side sliding sleeve (80) installed on a vertical tube (56), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30). The hinged support (44) is hinged to it via a b-shaped hinge, and the other end of the push-pull tube B (71) or the push-pull tube C (72) is hinged to the pull-out sliding support (73), and the pull-out sliding tube (75) is fixed on the pull-out sliding support (73). The pull-out sliding tube (75) is inserted into the pull-out sliding sleeve (74) fixed on the vertical tube (56) and is pulled or slid; thereby, the foldable push-pull vehicle can be folded and unfolded in the longitudinal direction; the above-mentioned side sliding hinged cross folding device B (7, 8, 27, 44, 48, 80) includes: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinged support (44), a hinged cross tube (48), an angular side sliding sleeve ( 80), one end of the hinged cross tube (48) is hinged to the upper longitudinal tube A and the upper longitudinal tube B directly, or is hinged to them via a horizontal tube hinge support (44) or a b-shaped hinge, and the other end is hinged to an angular side sliding sleeve (80) installed on the vertical tube (56), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30), the two hinged cross tubes on the same side are hinged to each other in the middle of the tube, and the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, and the hinge points of the lower longitudinal tube A and the lower longitudinal tube B, or the folding and unfolding of the foldable push-pull cart can be achieved without installing the vertical tube belt A or the vertical tube belt B;The above-mentioned side sliding folding device C (9, 10, 25, 26, 27, 29, 44, 80, 81, 82) includes: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a b-shaped hinge (27), a limiter (29), a horizontal tube hinge support (44), or further includes: a support (25), a push-pull tube (26), one end of the upper side push-pull tube (9) is directly hinged to the upper transverse horizontal tube A (81) and the transverse horizontal tube B (82), or is hinged to them via a b-shaped hinge, or is hinged to them via a horizontal tube hinge support, and the other One end is hinged to the angular side sliding sleeve (80) installed on the vertical tube (56), one end of the lower side push-pull tube (10) is hinged to the angular side sliding sleeve installed on the vertical tube (56), and the other end is hinged to the lower horizontal horizontal tube A (81) and horizontal horizontal tube B (82) or directly, or hinged via a b-shaped hinge, or hinged to them via a horizontal tube hinge support, in the middle of the upper side push-pull tube (9) or the lower side push-pull tube (10), or the push-pull tube (26) is hinged, and the other end of the push-pull tube is directly hinged to the middle horizontal tube (55) or hinged to it via a support (25), thereby realizing the folding and unfolding of the foldable push-pull cart in the horizontal direction. The limiter (29) is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve; the above-mentioned four-corner draw rod folding device (27, 70, 71, 72, 73, 74, 75) includes: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a draw sliding support (73), a draw sliding sleeve (74), a draw sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B (71) is hinged to the connecting rod A, one end of the push-pull tube C (72) is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or directly hinged, or hinged to it through a b-shaped hinge or a horizontal tube hinge support, and the other ends of the push-pull tube B (71) and the push-pull tube C (72) are hinged to the draw sliding support (7 3) Hinged on the longitudinal plane, the sliding sleeve (74) is installed on the upper end of the vertical tube (56), the sliding tube (75) is fixed on the sliding support (73), inserted into the sliding sleeve (74) and slides along it, and the cross tubes (70) are hinged in pairs at the middle. Their lower ends are respectively hinged to the transverse hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction, and their upper ends are respectively hinged to the sliding supports (73) on both sides of the transverse direction. When the corresponding folding device on the longitudinal plane is operated to fold, the push-pull tube B (71) or the push-pull tube C (72) is pushed, thereby pushing up the sliding support. Under the action of the cross tubes, the foldable push-pull vehicle can be folded and unfolded in the transverse direction.The above-mentioned transverse composite cross-folding device (60, 61, 62, 63, 78, 79, 80) comprises: a transverse horizontal cross tube A (60), a transverse horizontal cross tube B (61), a transverse oblique cross tube A (62), a transverse oblique cross tube B (63), a transverse horizontal rigid hinge (78), an oblique rigid hinge (79), one end of the transverse horizontal cross tube A (60) is fixed to the transverse horizontal rigid hinge (78) or other rigid hinge device, one end of the transverse horizontal cross tube B (61) is hinged to the hinge point (78.1) of the transverse horizontal rigid hinge (78) or the hinge point on other rigid hinge device, and the other ends of the transverse horizontal cross tube A (60) and the transverse horizontal cross tube B (61) are fixed to the transverse horizontal rigid hinge (78). The angular side sliding sleeves (80) are respectively hinged to the vertical tubes on both sides. The middle parts of the transverse oblique cross tube A (62) and the transverse oblique cross tube B (63) are respectively hinged to the middle parts of the transverse horizontal cross tube A (60) and the transverse horizontal cross tube B (61). The upper end fixing device of the transverse oblique cross tube A (62) has an oblique rigid hinge (79). The upper end of the transverse oblique cross tube B (63) is hinged to the hinge point (79.1) on the rigid hinge (79). The lower ends of the transverse oblique cross tube A (62) and the transverse oblique cross tube B (63) are respectively hinged to the transverse hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction. When the corresponding folding device on the longitudinal surface is operated to fold, the angular sliding sleeves are respectively hinged to the transverse horizontal cross tube A (60) and the transverse horizontal cross tube B (61). The folding and unfolding of the foldable push-pull cart in the lateral direction are achieved under the action of the composite cross motion. The above-mentioned lateral side sliding cross folding device (44, 80, 81, 82, 83) comprises: an angular side sliding sleeve (80), a lateral horizontal tube A (81), a lateral horizontal tube B (82), a lateral cross push tube (83), and a horizontal tube hinge support (44). After one end of the lateral horizontal tube A (81) is hinged to the lateral horizontal tube B (82) through a rigid hinge device, both sides of the lateral horizontal tube A (81) are hinged to the upper end of the vertical tube (56) or are directly hinged to the upper end of the vertical tube (56) or are fixed to the upper end of the vertical tube (56). The upper support (57) and the lower support (58) are hinged, and the transverse cross push tubes (83) are cross-hinged in pairs at the middle, and the lower ends are respectively hinged to the angular side sliding sleeves (80) on the vertical tubes (56) on both sides. The upper ends of the two transverse cross push tubes (83) are hinged to the transverse horizontal tube A (81) and the transverse horizontal tube B (82), or directly hinged, or hinged via a b-shaped hinge, or hinged via a horizontal tube hinge support. When the corresponding folding device on the longitudinal surface is operated to fold, the angular sliding sleeve is pushed, thereby pushing up the transverse horizontal tube A (81) and the transverse horizontal tube B (82), and at the same time driving the transverse cross push tubes (83) to rotate upward, thereby realizing the folding and unfolding of the foldable push-pull cart in the transverse direction.

[0010] In view of the above two independent claims, a further solution is: the above rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), a hinge support (39), a rigid hinge E (47), a rigid hinge J (49), a rigid hinge G (78), a rigid angle hinge (79), each rigid hinge A, a rigid hinge B, a rigid hinge C, a rigid hinge D, a rigid hinge member (17), a rigid hinge E (4 7), rigid hinge (49), rigid hinge (78), rigid angle hinge (79) are respectively fixed to upper U-shaped horizontal tube A (1) and upper U-shaped horizontal tube B (2), or to lower U-shaped horizontal tube A (3) and lower U-shaped horizontal tube B (4), or to middle U-shaped horizontal tube (5); respectively fixed to upper longitudinal tube A (50) and upper longitudinal tube B (51), or to lower longitudinal tube A (52) and lower longitudinal tube B (53), or to middle longitudinal tube (54) and middle transverse tube (55), or to The transverse horizontal tube A (81) and the transverse horizontal tube B (82) are fixed and then hinged via the corresponding hinge holes (17.1, 18.1, 39.1, 47.1, 78.1, 79.1) on the rigid hinge device, wherein the hinge connection with the hinge hole (17.1) is either directly hinged or hinged via the hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or to the rigid hinge member ( 17) is hinged at a hinge hole (17.1); a rigid hinge clamping groove (32) is provided on the rigid hinge device, and when the foldable push-pull cart is in an unfolded state, each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped, so that the pipe fittings hinged in pairs by the rigid hinge device are completely rigidly hinged; a mounting pad (15) is provided on the rigid hinge clamping groove of the rigid hinge device, which can reduce friction during rigid hinge clamping and reduce damage to each clamped pipe section.

[0011] With respect to the above two independent claims, a further solution is that the above-mentioned fixed handle (23) is either fixed to the ends of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or respectively fixed to the outsides of the transverse horizontal tube A and the transverse horizontal tube B; the above-mentioned handle device A (24) comprises: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing member (24.5), a latch (24.6), a positioning pin hole (24.7), the handle (24.1) is connected and fixed to the upper end of the handle rod (24.2), and a set of two semicircular transition sleeves (24.3) are symmetrically connected through the positioning pin hole (24 .7) is fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B, and the other two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing member (24.5) on the outside, and rotate together around the semicircular transition sleeve. After the fixing member is fixedly connected to the semicircular rotating sleeve, it is connected and fixed to the lower end of the handle rod, so that the handle device A can rotate freely around the end pipe axis of the lower U-shaped horizontal tube A or the end pipe axis of the lower U-shaped horizontal tube B. The latch (24.6) is fixed to the middle of the handle rod and is used to fix the handle device A after it is folded; the above-mentioned handle device B (38) includes: a handle (24.1), a hand The handle bar (24.2), or the fixed support (68), or the sliding support A (69), or the sliding support B (76), the handle is installed at the upper end of the handle bar, one side of the fixed support is hinged to the horizontal horizontal rigid hinge (78) on the horizontal horizontal cross tube A (60) and the horizontal horizontal cross tube B (61), or is hinged to the rigid support (85) hinge point on the rigid support tube A (86) and the rigid support tube B (87), and the other end is hinged to the lower end of the handle bar (24.2); the middle part of the sliding support A is provided with a slideway (69.1), which is assembled on the middle cross hinge point of the horizontal cross tube (70) or the horizontal cross push tube (83), and can be The sliding support armor can slide up and down along the slideway, and the sliding support armor completely clamps the two horizontal cross tubes or the two horizontal cross push tubes. The sliding support armor is then hinged to the lower end of the handle rod at the hinge hole (69.3). A clamping spring piece (69.2) is provided above the hinge hole where the sliding support armor is hinged to the handle rod. When the foldable push-pull cart is unfolded, the sliding support armor can be cross-limited by the unfolded horizontal cross tubes or the horizontal cross push tubes, so as to prevent the handle and the handle rod from rotating around the cross hinge point of the horizontal cross tubes or the horizontal cross push tubes, and can clamp the handle rod to fix it vertically. When the foldable push-pull cart is folded, the handle and the handle rod can slide down to an appropriate position and be clamped and fixed, so that the handle and the handle rod are not too high.The middle part of the sliding support (76) is provided with a slideway (76.1), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83) and can slide up and down along the slideway. The sliding support (76) clamps the two transverse cross tubes or one of the two transverse cross push tubes. The sliding support (76) is hinged to the lower end of the handle rod at a hinge hole (76.3). A clamping spring (76.2) and a limiting piece (76.4) are provided above the hinge hole where the sliding support (76) is hinged to the handle rod. When the foldable push-pull cart is unfolded, the sliding support (76) can be cross-limited by the limiting piece and the unfolded transverse cross tube or the transverse cross push tube, so that the handle and the handle rod will not rotate around the cross hinge point of the transverse cross tube or the transverse cross push tube, and can clamp the handle rod to fix it vertically. When the foldable push-pull cart is folded, the handle and the handle rod can slide downward to an appropriate position and be clamped and fixed, so that the handle and the handle rod are not too high.

[0012] In response to the above two independent claims, a further solution is: the above-mentioned foldable cart is either equipped with four universal wheels (22), or five universal wheels, or six or more universal wheels, and the four universal wheels are installed at the four corners of the foldable cart. The fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) of the four-wheel plane of the foldable cart, or are located on the two longitudinal sides of the four-wheel plane of the foldable cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7) to increase the loading capacity of the foldable cart.

[0013] With respect to the above two independent claims, a further solution is as follows: the above panel (21) is made of a rigid material, plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); used for placing transported items. The above flexible fabric (28), the braided ribbon (46), and the diagonally crossed ropes (84) are made of a flexible material, or are made into a concave pocket-shaped device on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon-woven manner, the ribbon weaving being either a single longitudinal or transverse weaving manner, or a cross-weaving manner; or are fixed to the four corners of the foldable push-pull truss in a rope-crossing manner.

[0014] With respect to the above two independent claims, a further solution is that the above vertical tube belt A (7) and vertical tube belt B (8) are either made of rigid materials, such as metal or plastic pipes, etc., or flexible materials, such as steel wire, steel belt, ribbon, cloth strip, rope, etc.

[0015] The present invention adopts the above technical solution, which has the following advantages:

[0016] 1. Using different folding principles and folding methods, the foldable push-pull cart can be folded and unfolded in different ways. Both folding and unfolding are very quick and easy.

[0017] 2. By adopting different folding principles and folding methods, the foldable push-pull cart can be folded into a sheet or stick shape. The folded foldable push-pull cart has a small size and is easy to carry and place.

[0018] 3. Adopting the rigid articulated principle, compared with the general folding push-pull cart, the foldable push-pull cart has the characteristics of high system rigidity after unfolding. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of symmetrical side-fixed connecting tube folding devices, rigid hinges, and is equipped with rigid panels, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully unfolded state.

[0020] Figure 2 yes Figure 1 The foldable push-pull cart in the picture adopts a set of side-fixed connecting tube folding devices and a five-wheel structure, showing the axonometric perspective of the fully unfolded state.

[0021] Figure 3 yes Figure 1 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0022] Figure 4 This is the foldable push-pull trolley in 1, equipped with a rigidly articulated central U-shaped horizontal tube, a support, a support sleeve, and an articulated push-pull tube. The three-layer foldable push-pull trolley is in an axonometric perspective view in a fully unfolded state.

[0023] Figure 5 yes Figure 4 Axonometric view of the medium foldable push-pull cart in a semi-folded state.

[0024] Figure 6 yes Figure 1 A foldable push-pull trolley with a rigidly articulated central U-shaped horizontal tube, showing the axonometric perspective of the three-tiered foldable push-pull trolley in its fully unfolded state.

[0025] Figure 7 yes Figure 1 Axonometric view of a foldable push-pull trolley in the fully expanded state, equipped with a rigidly articulated central U-shaped horizontal tube and vertical tubes with B, with a three-layer arrangement.

[0026] Figure 8This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two symmetrical sets of vertical tube folding devices in the middle of fixed side connecting tubes, rigid hinges, equipped with braided ribbons, a four-wheel structure, a handle device A, and a sheet folding. The foldable push-pull cart is in a fully expanded state.

[0027] Figure 9 yes Figure 8 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0028] Figure 10 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a set of cross-folding devices, rigid hinges, a rigid panel, a four-wheel structure, and a sheet-folding structure, and the foldable push-pull cart is in a fully unfolded state.

[0029] Figure 11 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a set of vertical tube folding devices with fixed side connecting tubes, rigid hinges, and is equipped with a rigid hinged central U-shaped horizontal tube, rigid panels, a four-wheel structure, and a sheet-folding, three-layer arrangement of the foldable push-pull cart in a fully unfolded state.

[0030] Figure 12 yes Figure 10 Axonometric view of a three-tiered foldable trolley with a rigidly articulated central U-shaped horizontal tube in its fully expanded state.

[0031] Figure 13 yes Figure 12 Axonometric view of a medium-sized foldable push-pull trolley with two symmetrical cross-folding devices and a three-layer foldable push-pull trolley in a fully unfolded state.

[0032] Figure 14 yes Figure 12 Axonometric view of a medium foldable trolley with vertical tubes and belts B, showing the three-tiered trolley in its fully expanded state.

[0033] Figure 15 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a set of side sliding hinged cross-folding devices, rigid hinges, equipped with rigid panels, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully unfolded state.

[0034] Figure 16 yes Figure 15 A foldable push-pull cart adopts two sets of symmetrical side sliding hinged cross-folding devices, is not equipped with vertical tube armor or the vertical tube armor is flexible, and is an axonometric stereogram of the foldable push-pull cart in a fully unfolded state.

[0035] Figure 17This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a central vertical tube side sliding folding device, rigid hinge, equipped with a rigid panel, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully unfolded state.

[0036] Figure 18 The present invention is a foldable push-pull cart, which adopts two symmetrical cross-folding devices, rigidly hinged, equipped with a handle device A, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in an axonometric perspective view in a fully unfolded state.

[0037] Figure 19 yes Figure 18 Axonometric view of a foldable push-pull cart in its fully unfolded state, utilizing a set of cross-folding mechanisms.

[0038] Figure 20 The present invention is a foldable push-pull cart, which adopts a single arrangement of cross-tube vertical tube folding device, rigidly hinged, equipped with a handle device A, a four-wheel structure, and a sheet-folding, and an axonometric perspective view of the foldable push-pull cart in a fully unfolded state.

[0039] Figure 21 The present invention is a foldable push-pull cart, which adopts a cross-folding device arranged singly on each longitudinal side, and is an axonometric perspective view of the foldable push-pull cart in a fully unfolded state.

[0040] Figure 22 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of mirror-symmetrical side sliding hinged cross-folding devices, rigid hinges, and is equipped with a handle device A. It has a four-wheel structure and folds in a sheet-like manner. The foldable push-pull cart is in a fully unfolded state.

[0041] Figure 23 yes Figure 22 The foldable push-pull cart in the figure adopts a set of side sliding hinged cross-folding devices, and the foldable push-pull cart is an axonometric perspective view of the fully unfolded state.

[0042] Figure 24 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of mirror-symmetrical side sliding and folding devices, rigid hinges, and is equipped with a rigid panel, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully unfolded state.

[0043] Figure 25 This is a foldable push-pull trolley of type 24, equipped with a central non-articulated U-shaped horizontal tube, supports, and articulated push-pull tubes. The three-layer structure of the foldable push-pull trolley is shown in an axonometric perspective view in its fully expanded state.

[0044] Figure 26 This is the foldable push-pull cart of No. 25, an axonometric view of the three-layer foldable push-pull cart in a semi-folded state.

[0045] Figure 27This is the foldable push-pull cart of No. 25, an axonometric view of the three-layer foldable push-pull cart in a fully folded state.

[0046] Figure 28 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of mirror-symmetrical middle sliding and folding devices, rigid hinges, and is equipped with a rigid panel, a four-wheel structure, a sheet-folding, and a three-layer arrangement of the foldable push-pull cart in a fully unfolded state.

[0047] Figure 29 yes Figure 28 The foldable push-pull cart in the figure adopts a set of middle sliding and folding devices, and the three-layer foldable push-pull cart is shown in an axonometric perspective view of the fully unfolded state.

[0048] Figure 30 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of mirror-symmetrical intermediate sliding and folding devices, rigid hinges, and is equipped with a rigid panel, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully unfolded state.

[0049] Figure 31 yes Figure 30 A foldable push-pull cart in the figure adopts a set of intermediate sliding and folding devices, and the foldable push-pull cart is in an axonometric perspective view of the fully unfolded state.

[0050] Figure 32 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a rotating folding device, rigid hinges, a rigid panel, a four-wheel structure, and a sheet-folding structure, and the foldable push-pull cart is in a fully unfolded state.

[0051] Figure 33 yes Figure 32 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0052] Figure 34 The foldable push-pull cart of the present invention adopts two sets of mirror-symmetrical side sliding and folding devices, rigidly hinged, equipped with handle device A, four-wheel structure, sheet-folding, and an axonometric perspective view of the foldable push-pull cart in a fully unfolded state.

[0053] Figure 35 yes Figure 34 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0054] Figure 36 yes Figure 34 The foldable push-pull cart in the figure adopts a five-wheel structure and is equipped with a concave flexible fabric. The foldable push-pull cart is an axonometric perspective view of the fully expanded state.

[0055] Figure 37The foldable push-pull cart of the present invention adopts two sets of mirror-symmetrical intermediate sliding and folding devices, rigidly hinged, equipped with handle device A, four-wheel structure, sheet-folding, and an axonometric perspective view of the foldable push-pull cart in a fully unfolded state.

[0056] Figure 38 yes Figure 37 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0057] Figure 39 The present invention is a foldable push-pull cart, which adopts a rotating folding device, a rigid hinge, a handle device A, a four-wheel structure, and a sheet-shaped folding, and an axonometric perspective view of the foldable push-pull cart in a fully unfolded state.

[0058] Figure 40 yes Figure 39 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0059] Figure 41 yes Figure 38 Axonometric view of the foldable push-pull cart in the fully folded state.

[0060] Figure 42 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a set of side-fixed connecting tube folding devices, rigid hinges, and is equipped with a handle device A, a four-wheel structure, and a sheet-folding structure. The foldable push-pull cart is in a fully expanded state.

[0061] Figure 43 yes Figure 42 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0062] Figure 44 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts two sets of side-fixed connecting tube folding devices, rigidly hinged, equipped with handle device A, six-wheel structure, sheet-folding, and the foldable push-pull cart is in a fully unfolded state.

[0063] Figure 45 yes Figure 44 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0064] Figure 46 It is a partial enlarged view of one of the rigid articulated devices of the foldable push-pull cart of the present invention in a semi-folded state.

[0065] Figure 47 yes Figure 28 A partial enlarged view of the upper rigid hinge device of the medium foldable push-pull cart in the semi-folded state.

[0066] Figure 48 It is a partial enlarged view of the matching relationship between the sliding sleeve in the sliding and folding device of the foldable push-pull cart of the present invention.

[0067] Figure 49 The present invention is a foldable push-pull cart, and a partially enlarged view of the assembly relationship between the upper push-pull tube, the lower push-pull tube, the sliding sleeve, the push-pull tube, the support, and the central U-shaped horizontal tube in the sliding and folding device.

[0068] Figure 50 It is a partial enlarged view of one of the folding devices of the foldable push-pull cart of the present invention when it is fully unfolded.

[0069] Figure 51 It is a partial enlarged view of one of the folding devices of the foldable push-pull cart of the present invention when it is half-folded.

[0070] Figure 52 It is a partial enlarged view of one of the rigid articulated devices of the foldable push-pull cart of the present invention in a semi-folded state.

[0071] Figure 53 It is a partial enlarged view of one of the rigid articulated devices of the foldable push-pull cart of the present invention in a semi-folded state.

[0072] Figure 54 It is a partial enlarged view of one of the folding devices of the foldable push-pull cart of the present invention when it is half-folded.

[0073] Figure 55 The present invention is a foldable push-pull cart, a schematic structural diagram of the handle device A.

[0074] Figure 56 It is a structural schematic diagram of the foldable push-pull cart and the multi-layer vertical riser device of the present invention.

[0075] Figure 57 It is a structural schematic diagram of the two-layer vertical riser device of the foldable push-pull cart of the present invention.

[0076] Figure 58 yes Figure 38 A partial enlarged view of the middle sliding and folding device and one of the rigid articulated devices of the medium foldable push-pull cart.

[0077] Figure 59 It is a partial enlarged view of one of the rigid articulated devices of the foldable push-pull cart of the present invention when it is in the fully unfolded state.

[0078] Figure 60 It is a partial enlarged view of one of the rigid articulated devices of the foldable push-pull cart of the present invention in a semi-folded state.

[0079] Figure 61 This is a partial enlarged view of the middle hinged structure of the two-layer vertical riser device of the foldable push-pull cart of the present invention.

[0080] Figure 62This is an axonometric perspective view of the foldable push-pull cart of the present invention, which has symmetrically arranged side sliding folding device B and side sliding folding device C, rigidly hinged, two-layer arrangement, four-wheel structure, and stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0081] Figure 63 yes Figure 62 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0082] Figure 64 yes Figure 62 Axonometric view of a foldable push-pull trolley in a fully expanded state, configured with a rigidly articulated central longitudinal tube and a central transverse tube, supports, articulated push-pull tubes, and diagonally crossed ropes, with the three-tiered foldable push-pull trolley arranged in a fully expanded state.

[0083] Figure 65 yes Figure 64 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0084] Figure 66 This is an axonometric perspective view of the foldable push-pull cart of the present invention, with the side-fixed connecting tube folding device and the four-corner pull-rod folding device symmetrically arranged longitudinally and transversely, rigidly hinged, handle device B and sliding support device A, four-wheel structure, stick-shaped folding, and the foldable push-pull cart in a fully unfolded state.

[0085] Figure 67 yes Figure 66 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0086] Figure 68 This is an axonometric perspective view of the foldable push-pull cart of the present invention, with vertical tube folding devices and four-corner pull-rod folding devices arranged symmetrically in the longitudinal and transverse directions, rigid hinges, handle device B and sliding support B, woven ribbons, a four-wheel structure, and stick-shaped folding. The foldable push-pull cart is in a fully expanded state.

[0087] Figure 69 yes Figure 68 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0088] Figure 70 This is an axonometric perspective view of the foldable push-pull cart of the present invention, with a side sliding folding device B and a transverse composite cross-folding device symmetrically arranged longitudinally and transversely, a rigid hinge, a handle device B and a fixed support, a six-wheel structure, diagonally crossed ropes, and a stick-shaped folding structure, showing the foldable push-pull cart in a fully expanded state.

[0089] Figure 71This is an axonometric perspective view of the foldable push-pull cart of the present invention, which is arranged with four-corner pull-out rod folding devices and a central vertical tube side pull-out sliding folding device, rigid hinge, handle device B and sliding support B, four-wheel structure, diagonally crossed ropes, and stick-shaped folding. The foldable push-pull cart is in a fully expanded state.

[0090] Figure 72 yes Figure 71 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0091] Figure 73 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts symmetrically arranged cross-folding devices and four-corner pull-rod folding devices, rigid hinges, handle device B and sliding support B, a four-wheel structure, and stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0092] Figure 74 yes Figure 73 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0093] Figure 75 This is the foldable push-pull cart of the present invention, which adopts the symmetrical arrangement of the middle sliding folding device, the middle vertical tube side sliding folding device and the horizontal composite cross folding device, rigid hinge, handle device B and fixed support, four-wheel structure, equipped with push-pull tube A, stick-shaped folding, and the axonometric stereogram of the foldable push-pull cart in the fully unfolded state.

[0094] Figure 76 yes Figure 74 Axonometric view of the foldable push-pull cart in a semi-folded state.

[0095] Figure 77 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a symmetrically arranged vertical tube side sliding folding device and a horizontal composite cross folding device, rigid hinge, handle device B and fixed support, six-wheel structure, braided ribbon, and stick-shaped folding. The foldable push-pull cart is in a fully expanded state.

[0096] Figure 78 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a cross-folding device and a four-corner pull-rod folding device arranged separately on both longitudinal sides, a rigid hinge, a handle device B and a sliding support B, a four-wheel structure, and a stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0097] Figure 79 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a cross-folding device and a four-corner pull-rod folding device arranged crosswise in a longitudinal side plane, a rigid hinge, a handle device B and a sliding support B, a four-wheel structure, and a stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0098] Figure 80This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a cross-tube vertical tube folding device and a four-corner pull-rod folding device, a rigid hinge, a handle device B and a sliding support B, a four-wheel structure, and a stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0099] Figure 81 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a middle sliding folding device and a lateral side sliding cross-folding device, a rigid hinge, a handle device B and a sliding support A, a four-wheel structure, and a stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0100] Figure 82 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a middle sliding folding device and a lateral side sliding cross-folding device, a rigid hinge, a handle device B and a fixed support, a four-wheel structure, diagonally crossed ropes, and a stick-shaped folding. The foldable push-pull cart is in a fully expanded state.

[0101] Figure 83 This is an axonometric perspective view of the foldable push-pull cart of the present invention, which adopts a side sliding hinged cross-folding device B and a lateral side sliding cross-folding device, a rigid hinge, a handle device B and a fixed support, a four-wheel structure, and a stick-shaped folding. The foldable push-pull cart is in a fully unfolded state.

[0102] Figure 84 yes Figure 62 A partial enlarged view of the assembly structure at the upper docking corner of the foldable push-pull cart.

[0103] Figure 85 yes Figure 63 A partial enlarged view of the assembly structure at the angled side sliding sleeve of the foldable push-pull cart.

[0104] Figure 86 yes Figure 75 A partially enlarged view of the middle assembly structure of the foldable push-pull cart shown in FIG.

[0105] Figure 87 yes Figure 76 A partial enlarged view of the rigid corner hinge structure of the foldable push-pull cart shown in FIG.

[0106] Figure 88 yes Figure 76 A partial enlarged view of the assembly structure at the angled side sliding sleeve of the foldable push-pull cart.

[0107] Figure 89 yes Figure 76 A partial enlarged view of the foldable push-pull cart, handle device B and fixed support structure.

[0108] Figure 90 yes Figure 66A partially enlarged view of the corner lever structure of the four-corner pull-out rod folding device of the foldable push-pull cart.

[0109] Figure 91 yes Figure 67 A partially enlarged view of the corner lever structure of the four-corner pull-out rod folding device of the foldable push-pull cart.

[0110] Figure 92 yes Figure 69 A partial enlarged view of the rigid articulated device structure of the foldable push-pull cart.

[0111] Figure 93 yes Figure 66 A partial enlarged view of the structure of the handle device B and the sliding support A of the foldable push-pull cart.

[0112] Figure 94 yes Figure 68 A partial enlarged view of the structure of the handle device B and the sliding support B of the foldable push-pull cart.

[0113] Figure 95 yes Figure 70 A partial enlarged view of the assembly structure at the angled side sliding sleeve of the foldable push-pull cart.

[0114] Figure 96 yes Figure 81 A partial enlarged view of the assembly structure of the handle device B and the sliding support A of the foldable push-pull cart.

[0115] Figure 97 yes Figure 82 A partially enlarged view of the transversely arranged rigid articulated device structure of the foldable push-pull cart.

[0116] Figure 98 yes Figure 83 A partial enlarged view of the structure of the rigid hinge device, handle device B and sliding support A in the lateral sliding cross-folding device of the foldable push-pull cart. DETAILED DESCRIPTION

[0117] Reference Figures 1 to 61, upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6) or two-layer vertical riser device (40) or multi-layer vertical riser device (30), vertical tube A (7) vertical tube B (8), support (25), push-pull tube (26), rigid hinge device, fixed connecting tube folding device, fixed connecting tube middle vertical tube folding device Device, side sliding folding device, middle sliding folding device, side rotating folding device, cross folding device, cross tube vertical tube folding device, middle vertical tube side sliding folding device, side sliding hinged cross folding device, fixed handle (23), handle device A (24), flexible (28), panel (21), universal wheel (22), also includes: transverse tube (20), eccentric hinge (35), supporting sleeve (37), braided ribbon (46), upper U-shaped The horizontal tube A is hinged to the upper U-shaped horizontal tube B via a rigid hinge device, the lower U-shaped horizontal tube A is hinged to the lower U-shaped horizontal tube B via a rigid hinge device, and the middle U-shaped horizontal tube A is hinged to each other or to a rigid hinge device, or not hinged, and their two sides are hinged to the vertical U-shaped tube, or to two layers of end vertical tube devices, or to multiple layers of end vertical tube devices. According to different folding methods, on the longitudinal surface of the foldable push-pull vehicle, a side-fixed connecting tube folding device, a side-fixed connecting tube middle vertical tube folding device, a side-sliding folding device, a middle sliding folding device, a side-rotating folding device, a cross-folding device, a cross-tube vertical tube folding device, a middle vertical tube side-sliding folding device, or a side-sliding hinged cross-folding device, etc., can be installed, and can be folded and unfolded in a sheet-like manner along the longitudinal direction of the foldable push-pull vehicle;Depending on the different foldable push-pull carts, a fixed handle or a handle device A is installed, the universal wheel is fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device, the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged with the vertical U-shaped tube, the two-layer end vertical tube device, and the multi-layer end vertical tube device, or is directly hinged or hinged through an eccentric hinge. For multi-layer foldable push-pull carts, the middle U-shaped horizontal tube is directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is slidingly hinged through a support sleeve, so that it can be hinged directly. The foldable push-pull carts can be used to push the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B and the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B upwards, and then hinged by the rigid hinge device, driving the middle U-shaped horizontal tube on the other side to rotate and slide. The horizontal tube is installed in the middle, and its axis is concentric with the axis of the hinge hole of the rigid hinge device. Foldable push-pull carts for different purposes can use rigid hard panels or flexible fabrics. In order to improve the carrying capacity of the foldable push-pull carts, flexible fabrics are used as well as woven ribbons at the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. When folding the foldable cart, the upper U-shaped horizontal tube A and upper U-shaped horizontal tube B are simultaneously lifted upward near the rigid hinge device and rotated around the rigid hinge point. Under the action of each folding device, the foldable cart folds into a sheet shape in different folding positions. When unfolding the foldable cart, the upper U-shaped horizontal tube A and upper U-shaped horizontal tube B are pulled apart to the sides. Under the action of gravity, the foldable cart automatically unfolds and the rigid hinge is self-locking after passing the dead point to achieve the unfolded state.

[0118] Furthermore, the side-fixed connecting tube folding device comprises: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), a horizontal tube hinge support (44), and a hinge (45). One end of the connecting rod A (41) is directly hinged to the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, or is hinged via a horizontal tube hinge support fixed on the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, and the other end is directly hinged to the vertical U-shaped tube on the opposite side, or is hinged via a vertical tube hinge support fixed on the vertical U-shaped tube, the upper end of the connecting rod B is directly hinged to the middle of the connecting rod A, or is hinged via a hinge, and the lower end of the connecting rod B is hinged to the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B on the same side, or Directly hinged, or hinged with it via a b-shaped hinge, so as to realize the folding and unfolding of the foldable push-pull cart; the vertical tube folding device in the side fixed connecting tube includes: vertical tube belt A (7), vertical tube belt B (8), connecting rod A (41), vertical tube hinge support (43), horizontal tube hinge support (44), one end of connecting rod A (41) is directly hinged with the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, or hinged with it via a b-shaped hinge, or hinged with the horizontal tube hinge support fixed on the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, and the other end is directly hinged with the vertical U-shaped tube on the opposite side, or hinged with the vertical tube hinge support fixed on the vertical U-shaped tube, or hinged with it via a b-shaped hinge, the vertical tube belt A or the vertical tube One end of belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B or the middle hinge point of the two middle U-shaped horizontal tubes, so as to realize the folding and unfolding of the foldable push-pull cart; the side sliding folding device includes: an upper side push-pull tube (9), a lower side push-pull tube (10), a side sliding sleeve (13), a b-shaped hinge (27), a limiter (29), or includes: a support (25), a push-pull tube (26), a horizontal tube hinge support (44), one end of the upper side push-pull tube is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B directly, or is hinged to them via a b-shaped hinge, or via a horizontal tube hinge support, and the other end is hinged to the device A side sliding sleeve is hinged on a vertical U-shaped tube, or a two-layer vertical riser device, or a multi-layer vertical riser device; one end of a lower side push-pull tube is hinged to a side sliding sleeve installed on the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device; the other end is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or hinged thereto via a b-shaped hinge; a push-pull tube is hinged in the middle of the upper side push-pull tube or the lower side push-pull tube, and the other end of the push-pull tube is directly hinged to the middle U-shaped horizontal tube, or hinged thereto via a support, thereby realizing the folding and unfolding of the foldable push-pull cart; a limiter is installed in the middle of the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device, to limit the maximum sliding position of the side sliding sleeve;The intermediate sliding and folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a central push-pull tube (11), a central sliding sleeve (12), a limiter (29), one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, and the other end is hinged to the middle of the two central U-shaped horizontal tubes. The folding and unfolding of the foldable push-pull vehicle can be realized by hinged connection at one end, the middle sliding sleeve is inserted into the vertical tube belt A or the vertical tube belt B and can slide on it, one end of the symmetrically distributed middle push-pull tube is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the other end is hinged to the middle sliding sleeve, thereby realizing the folding and unfolding of the foldable push-pull vehicle, and the limiter is installed on the vertical tube belt A or the vertical tube belt B to limit the maximum sliding position of the middle sliding sleeve; the side-rotating folding device comprises: an upper side-pushing and pulling tube (9), a lower side-pushing and pulling tube (10), a b-shaped hinge (27), a rotating rod (33), a limiter (34), a connecting piece (36), one end of the upper side-pushing and pulling tube is hinged to the upper U-shaped horizontal tube A and the upper U The horizontal tube B is directly hinged or hinged therewith via a b-shaped hinge, and the other end is hinged to one end of the rotating rod, and the other end of the rotating rod is hinged to the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device. One end of the lower side push-pull tube is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B or hinged therewith via a b-shaped hinge, and the other end is provided with a limit block hinged at the same point or not at the same point with the side hinge point of the upper side push-pull tube. When the foldable push-pull cart is unfolded, the limit block can be close to the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device, thereby realizing the folding and limited unfolding of the foldable push-pull cart; the cross-folding device comprises: a b-shaped hinge (27), horizontal tube hinge support (44), longitudinal cross tube (77), longitudinal cross tube (77) is arranged symmetrically in a cross arrangement in the longitudinal two side planes, or is arranged crosswise in the longitudinal one side plane, or is arranged singly in the longitudinal two side planes, one end of the longitudinal cross tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them through the horizontal tube hinge support or through the b-shaped hinge, and the other end is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or is hinged to them through the b-shaped hinge. The middle parts of the symmetrically arranged longitudinal cross tubes do not need to be hinged to each other, thereby realizing the folding and unfolding of the foldable push-pull cart;The cross tube vertical tube folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge support (44), a longitudinal cross tube (77), the longitudinal cross tube (77) is arranged in a symmetrical projection or mirror image cross-direction in parallel planes on both sides of the longitudinal direction, or is arranged in a single oblique direction in a plane on one side of the longitudinal direction, one end of the longitudinal cross tube is directly hinged to the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, or is hinged to it through the horizontal tube hinge support or through the b-shaped hinge, and the other end is hinged to the lower U-shaped horizontal tube A or the upper U-shaped horizontal tube B. The horizontal tube A or the lower U-shaped horizontal tube B is directly hinged or hinged with it through a b-shaped hinge. The middle parts of the symmetrically arranged longitudinal cross tubes do not need to be hinged to each other. The upper end of the vertical tube belt B is hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the lower end of the vertical tube belt B is hinged to the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. The two ends of the vertical tube belt A are hinged at the hinge point with the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B and the hinge point with the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. After being hinged, the middle part thereof is hinged with the middle hinge point of the two middle U-shaped horizontal tubes, thereby realizing the folding and unfolding of the foldable push-pull cart; the middle vertical tube side sliding folding device comprises: vertical tube belt A (7), vertical tube belt B (8), upper side push-pull tube (9), side sliding sleeve (13), b-shaped hinge (27), limiter (29), horizontal tube hinge support (44), one end of the upper side push-pull tube is directly hinged with the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged via the horizontal tube hinge support or is hinged via the b-shaped support. The hinge is hinged therewith, and the other end is hinged to a side sliding sleeve installed on a vertical U-shaped tube, or a two-layer vertical riser device, or a multi-layer vertical riser device. The limiter is installed in the middle of the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device to limit the maximum sliding position of the side sliding sleeve. The two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge points of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, thereby realizing the folding and unfolding of the foldable push-pull cart;The side sliding hinged cross folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a side sliding sleeve (13), a b-shaped hinge (27), a horizontal tube hinge support (44), and a hinged cross tube (48). One end of the hinged cross tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via the horizontal tube hinge support or the b-shaped hinge, and the other end is hinged to the side sliding sleeve installed on the vertical U-shaped tube, or the two-layer vertical riser device, or the multi-layer vertical riser device. The two hinged cross tubes on the same side are hinged to each other in the middle of the tube. The two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge points of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or the vertical tube belt A or the vertical tube belt B are not installed, so as to realize the folding and unfolding of the foldable push-pull cart. When folding the foldable cart, the upper U-shaped horizontal tube A and upper U-shaped horizontal tube B are simultaneously lifted upward near the rigid hinge device and rotated around the rigid hinge point. Under the action of the nine folding devices described above, the foldable cart folds into a sheet shape in different folding modes. When unfolding the foldable cart, the upper U-shaped horizontal tube A and upper U-shaped horizontal tube B are pulled apart to the sides. Under the action of gravity and the folding devices, the foldable cart automatically unfolds, self-locks at the dead point, and rigidly hinges to achieve the unfolded state.

[0119] Furthermore, in addition to being assembled with vertical U-shaped tubes, the foldable push-pull cart can also be assembled with a multi-layer end vertical tube device (30) or a two-layer end vertical tube device (40). The multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented tube, and the lower connecting piece is fixed to the lower segmented tube. One end of the pipe is fixed, and the middle section connecting piece is fixed to the other end of the upper and lower section pipes respectively, or fixed to the other end of the upper and lower section pipes respectively, and fixed to both ends of the middle section pipes above four layers. The semicircular sleeve is symmetrically installed and fixed by a limit pin on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the U-shaped bottom edges on both sides of the middle U-shaped horizontal pipe after being hinged by a rigid hinge device. The upper connecting piece, the lower connecting piece and the middle section connecting piece are sleeved on The semicircular sleeve is put on to form a rigidly connected multi-layer end straight pipe device. The semicircular sleeve has flanges (30.7) at both ends to prevent the multi-layer end vertical pipe device from lateral movement. At the same time, each U-shaped horizontal pipe can also rotate around each connecting piece. The two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the straight pipe. The other end is fixed, and the semicircular sleeves are symmetrically installed and fixed by limit pins on the U-shaped bottom edges of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B after being hinged via a rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeves to form a rigidly connected two-layer end vertical tube device. The semicircular sleeves have flanges (30.7) at both ends to prevent the two-layer end vertical tube device from lateral movement. At the same time, each U-shaped horizontal tube can also rotate around each connecting piece.

[0120] Reference Figures 62 to 98, upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), middle longitudinal tube (54), middle transverse tube (55), vertical tube (56), upper support (57), lower support (58), middle support (59), transverse horizontal tube A (81), transverse horizontal tube B (82), locking piece (65), transverse hinge (66) wheel support (67), support (25), push-pull tube (26), rigid hinge device, sliding folding device B, fixed connecting tube folding device, fixed connecting tube middle vertical tube folding device, middle sliding folding device, rotating folding device, cross folding device, cross tube vertical tube folding device, middle vertical tube side pull sliding folding device, sliding hinge cross Fork folding device B, side sliding folding device C, four-corner pull-out rod folding device, horizontal composite cross folding device, horizontal side sliding cross folding device, fixed handle (23), handle device B (38), flexible fabric (28), universal wheel (22), also includes: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), upper longitudinal tube A and upper longitudinal tube B are hinged through a rigid hinge device, lower longitudinal tube A and lower longitudinal tube B are hinged through a rigid hinge device, horizontal horizontal tube A and horizontal horizontal tube B are hinged through a rigid hinge device, after rigid hinge, in the horizontal arrangement state of two vertical planes, both sides are directly hinged to the two ends of the vertical tube, or are hinged to the upper support and lower support fixed on the vertical tube, three or more layers of multi-layer foldable push rod The trolley is a foldable push-pull trolley in which the middle longitudinal tube and the middle transverse tube are hinged to each other by rigid hinge devices in pairs or without hinges. The other ends of the middle longitudinal tubes and the middle transverse tube are hinged to the vertical tube in the middle or directly, or are hinged to the vertical tube through a middle support fixed on the vertical tube. According to the folding principle and folding method, on the longitudinal surface of the foldable push-pull trolley, a sliding folding device B is installed, a fixed connecting tube folding device is installed, a vertical tube folding device in the fixed connecting tube is installed, an intermediate sliding folding device is installed, a rotating folding device is installed, a cross folding device is installed, a cross tube vertical tube folding device is installed, a middle vertical tube sliding folding device is installed, or a sliding hinged cross folding device B is installed. On the transverse surfaces at both ends, either a side sliding folding device C is installed, or a four-corner pull-out rod folding device is installed, or a transverse composite cross-folding device is installed, or a transverse side sliding cross-folding device is installed. Depending on the different foldable push-pull carts, either a fixed handle is installed, or a handle device B is installed. Four universal wheels are fixed to the lower end of the vertical tube through wheel supports. The upper longitudinal tube A, the upper longitudinal tube B, the lower longitudinal tube A, the lower longitudinal tube B, or the transverse horizontal tube A and the transverse horizontal tube B are directly hinged to the vertical tube, or are hinged through an eccentric hinge, or are hinged through the upper support and lower support fixed to the two ends of the vertical tube. For multi-layer foldable push-pull carts, the middle longitudinal tube and the middle transverse tube are either hinged to the middle support fixed in the middle of the vertical tube, or are directly hinged to the four corner vertical tubes.Or one side is hinged to the vertical tube, and the other side is hinged by sliding through the support sleeve, so that the support can be pushed under the action of the push-pull tube on the directly hinged side and the central longitudinal tube and the central transverse tube on the same corner side can be driven to rotate upward, and the central longitudinal tube and the central transverse tube on the other side can also be driven to rotate and slide, and rotate upward synchronously with the upper longitudinal tube B, the lower longitudinal tube A, the lower longitudinal tube B and the central longitudinal tube. Foldable push-pull carts for different purposes can be made of either flexible fabric (28), braided ribbon (46), or diagonal Cross ropes (84), or steel ropes, or wire mesh, in order to further improve the bearing capacity and system rigidity of the foldable push-pull cart, or flexible fabrics are configured, or braided ribbons, or wire ropes, or wire mesh are configured transversely on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or braided ribbons, or steel ropes, or wire mesh are configured in the diagonal cross direction of the foldable push-pull cart when viewed from above, which can not only improve the bearing load of the foldable push-pull cart after unfolding, but also greatly improve its system rigidity. When folding the foldable cart, the upper longitudinal tube A and upper longitudinal tube B are simultaneously lifted upward at the rigid hinge device on the longitudinal surface and rotated around the rigid hinge point. Under the action of the longitudinal and transverse folding devices, the three-dimensional dimensions of the foldable cart change along the three directions, and it folds into a stick shape in different folding methods. When unfolding the foldable cart, the upper longitudinal tube A and upper longitudinal tube B are pulled apart around the rigid hinge point. Under the action of gravity, the foldable cart automatically unfolds, and the rigid hinge is self-locking after passing the dead point to achieve the unfolded state.

[0121] Furthermore, the side sliding folding device B comprises: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a b-shaped hinge (27), a limiter (29), or further comprises: a support (25), a push-pull tube (26), a horizontal tube hinge support (44), and on the longitudinal surface of the foldable push-pull vehicle, one end of the upper side push-pull tube is directly hinged to the upper longitudinal tube A and the upper longitudinal tube B, or is hinged to them via a b-shaped hinge, or is hinged to them via a horizontal tube hinge support, and the other end is hinged to the angular side sliding sleeve installed on the vertical tube, and one end of the lower side push-pull tube is hinged to the angular side sliding sleeve installed on the vertical tube. The sleeve is hinged, and the other end is hinged to the lower longitudinal tube A and the lower longitudinal tube B or directly, or hinged via a b-shaped hinge, or hinged to them via a horizontal tube hinge support. Similarly, on the transverse surface of the foldable push-pull cart, it can also be equivalent to a sliding folding device C and a sliding folding device B, that is: one end of the upper push-pull tube is hinged to the upper transverse horizontal tube A and the upper transverse horizontal tube B or directly, or hinged via a b-shaped hinge, or hinged to them via a horizontal tube hinge support, and the other end is hinged to the angular side sliding sleeve installed on the vertical tube; one end of the lower push-pull tube is hinged to the angular side sliding sleeve installed on the vertical tube, and the other end is hinged to The lower transverse horizontal tube A and the lower transverse horizontal tube B are either directly hinged, or hinged via a b-shaped hinge, or hinged to the horizontal tube hinge support. In the middle of the upper side push-pull tube or the lower side push-pull tube, the push-pull tube is hinged, and the other end of the push-pull tube is directly hinged to the middle longitudinal tube, or hinged to the middle longitudinal tube via a support, so that the foldable push-pull vehicle can be folded and unfolded. The limiter is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve. The side fixed connecting tube folding device includes: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), a horizontal tube An articulated support (44), an articulated member (45), one end of the connecting rod A being directly articulated to the upper longitudinal tube A or the upper longitudinal tube B, or being articulated via a b-shaped articulated member, or being articulated via a horizontal tube articulated support fixed to the upper longitudinal tube A or the upper longitudinal tube B, the other end being directly articulated to the vertical tube on the opposite side, or being articulated via a vertical tube articulated support fixed to the vertical tube, the upper end of the connecting rod B being directly articulated to the middle of the connecting rod A, or being articulated via an articulated member, the lower end of the connecting rod B being directly articulated to the lower longitudinal tube A or the lower longitudinal tube B on the same side, or being articulated via a b-shaped articulated member, thereby enabling the folding and unfolding of the foldable push-pull cart;The vertical tube folding device in the side-fixed connecting tube comprises: a vertical tube belt A (7), a vertical tube belt B (8), a connecting rod A (41), a vertical tube hinge support (43), and a horizontal tube hinge support (44). One end of the connecting rod A is directly hinged to the upper longitudinal tube A or the upper longitudinal tube B, or is hinged to it via a b-shaped hinge, or is hinged to it via a horizontal tube hinge support fixed on the upper longitudinal tube A or the upper longitudinal tube B. The other end is directly hinged to the vertical tube on the opposite side, or is hinged to it via a vertical tube hinge support fixed on the vertical U-shaped tube, or is hinged to it via a b-shaped hinge. One end of the vertical tube belt A or the vertical tube belt B is hinged to the upper longitudinal tube A and the upper longitudinal tube B. The middle sliding folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a middle push-pull tube (11), a middle sliding sleeve (12), a position limiting member (29), one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper longitudinal tube A and the upper longitudinal tube B, and the other end is hinged to the hinge point of the lower longitudinal tube A and the lower longitudinal tube B. In the multi-layer foldable push-pull cart, the vertical tube belt A or the middle sliding folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a middle push-pull tube (11), a middle sliding sleeve (12), a position limiting member (29), one end of the vertical tube belt A or the vertical tube belt B is hinged to the hinge point of the upper longitudinal tube A and the upper longitudinal tube B, and the other end is hinged to the hinge point of the lower longitudinal tube A and the lower longitudinal tube B. The middle part is hinged to the middle longitudinal tubes in pairs by a rigid hinge device, or without hinge, the middle sliding sleeve is inserted into the vertical tube belt A or the vertical tube belt B and can slide thereon, one end of the symmetrically distributed middle push-pull tube is hinged to the lower longitudinal tube A and the lower longitudinal tube B, and the other end is hinged to the middle sliding sleeve, so that the foldable push-pull vehicle can be folded and unfolded, and the limiter is installed at the upper end of the vertical tube belt A or the vertical tube belt B to limit the maximum sliding position of the middle sliding sleeve; the side-rotating folding device includes: an upper side-pushing tube (9), a lower side-pushing tube (10), a b-shaped hinge (27), a rotating rod (33), a limiter (34), a connecting piece (36 ), one end of the upper side push-pull tube is hinged to the upper longitudinal tube A and the upper longitudinal tube B directly or via a b-shaped hinge, and the other end is hinged to one end of a rotating rod, and the other end of the rotating rod is hinged to the vertical tube, or the two-layer vertical riser device, or the multi-layer vertical riser device; one end of the lower side push-pull tube is hinged to the lower longitudinal tube A and the lower longitudinal tube B directly or via a b-shaped hinge, and the other end is provided with a limit block hinged to the upper side push-pull tube at a co-point or non-co-point. When the foldable push-pull cart is unfolded, the limit block can be in close contact with the vertical tube, or the two-layer vertical riser device, or the multi-layer vertical riser device, thereby realizing the folding and limited unfolding of the foldable push-pull cart;The cross-folding device comprises: a b-shaped hinge (27), a horizontal tube hinge support (44), and a longitudinal cross tube (77). The longitudinal cross tube (77) is arranged symmetrically and crosswise in the longitudinal two side planes, or is arranged crosswise in the longitudinal one side plane, or is arranged singly in the longitudinal two side planes. One end of the longitudinal cross tube is directly hinged to the upper longitudinal tube A and the upper longitudinal tube B, or is hinged to them via a horizontal tube hinge support or a b-shaped hinge. The other end is directly hinged to the lower longitudinal tube A and the lower longitudinal tube B, or is hinged to them via a horizontal tube hinge support or a b-shaped hinge. The middle parts of the symmetrically cross-arranged longitudinal cross tubes do not need to be hinged to each other, thereby realizing the folding and unfolding of the foldable push-pull cart. The cross tube vertical tube folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge support (44), and a longitudinal cross tube (77). The longitudinal cross tubes are arranged in a symmetrical projection or mirror image cross pattern in parallel planes on both sides of the longitudinal direction, or are arranged in a single oblique direction in a plane on one side of the longitudinal direction. One end of the longitudinal cross tube is directly hinged to the upper longitudinal tube A or the upper longitudinal tube B, or is hinged to it via a horizontal tube hinge support or a b-shaped hinge, and the other end is directly hinged to the lower longitudinal tube A or the lower longitudinal tube B, or is hinged to it via a b-shaped hinge. The symmetrically arranged longitudinal cross tubes do not need to be hinged to each other. The upper end of the vertical tube belt B is hinged to the upper longitudinal tube A and the upper longitudinal tube B. The hinge point is hinged, the lower end of the vertical tube belt B is hinged with the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, and the two ends of the vertical tube belt A are hinged with the hinge point of the upper longitudinal tube A and the upper longitudinal tube B and hinged with the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, and then the middle part is hinged with the middle hinge point of the two middle longitudinal tubes, thereby realizing the folding and unfolding of the foldable push-pull cart; the middle vertical tube side-drawing sliding folding device includes: vertical tube belt A (7), vertical tube belt B (8), push-pull tube A (64), angular side sliding sleeve (80), B-shaped hinge (27), limiter (29), horizontal tube hinge support (44), and also includes: push-pull tube B (71), push-pull tube C (7 2) Pull out the sliding support (73), pull out the sliding sleeve (74), pull out the sliding tube (75), the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged with the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, and the hinge points of the lower longitudinal tube A and the lower longitudinal tube B, one end of the push-pull tube is directly hinged with the upper longitudinal tube A and the upper longitudinal tube B or the lower longitudinal tube A and the lower longitudinal tube B, or is hinged with them through a horizontal tube hinge support or a b-shaped hinge, and the other end is hinged with an angular side sliding sleeve installed on the vertical tube, or a two-layer vertical riser device, or a multi-layer vertical riser device, and a limiter is installed in the middle of the vertical tube, or the two-layer vertical riser device, or the multi-layer vertical riser device to limit the maximum sliding position of the side sliding sleeve;One end of the push-pull tube B or the push-pull tube C is directly hinged to the lower longitudinal tube A and the lower longitudinal tube B, or is hinged to the lower longitudinal tube B through a horizontal tube hinge support or a b-shaped hinge. The other end of the push-pull tube B or the push-pull tube C is hinged to the sliding support. The sliding support is fixed with a sliding tube. The sliding tube is inserted into the sliding sleeve fixed to the vertical tube and is pulled or slid. Thus, the foldable push-pull vehicle can be folded and unfolded in the longitudinal direction. The side sliding hinged cross folding device B includes: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge Support (44), hinged cross tube (48), angular side sliding sleeve (80), one end of the hinged cross tube is directly hinged to the upper longitudinal tube A and the upper longitudinal tube B, or is hinged to them through a horizontal tube hinge support or a b-shaped hinge, and the other end is hinged to the angular side sliding sleeve installed on the vertical tube, or a two-layer vertical riser device, or a multi-layer vertical riser device. The two hinged cross tubes on the same side are hinged to each other in the middle of the tube, and the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, and the hinge points of the lower longitudinal tube A and the lower longitudinal tube B. Alternatively, the folding and unfolding of the foldable push-pull cart can be realized without installing the vertical tube belt A or the vertical tube belt B; the side sliding folding device C comprises: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a b-shaped hinge (27), a limiter (29), a horizontal tube hinge support (44), or further comprises: a support (25), a push-pull tube (26), one end of the upper side push-pull tube is directly hinged to the upper transverse horizontal tube A and the transverse horizontal tube B, or is hinged via a b-shaped hinge. The foldable push-pull trolley is hinged or hinged to it through a horizontal tube hinge support, and the other end is hinged to the angular side sliding sleeve installed on the vertical tube. One end of the lower side push-pull tube is hinged to the angular side sliding sleeve installed on the vertical tube, and the other end is directly hinged to the lower horizontal horizontal tube A and horizontal horizontal tube B, or hinged through a b-shaped hinge, or hinged to it through a horizontal tube hinge support. In the middle of the upper side push-pull tube or the lower side push-pull tube, the push-pull tube is hinged, and the other end of the push-pull tube is directly hinged to the middle horizontal tube, or hinged to it through a support, thereby realizing the folding and unfolding of the foldable push-pull trolley in the horizontal direction. The limiter is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve.The four-corner draw rod folding device comprises: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a draw sliding support (73), a draw sliding sleeve (74), a draw sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B is hinged to the connecting rod A, one end of the push-pull tube C is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or is directly hinged, or is hinged to it via a b-shaped hinge or a horizontal tube hinge support, the other ends of the push-pull tube B and the push-pull tube C are hinged to the draw sliding support on the longitudinal plane, the draw sliding sleeve is installed at the upper end of the vertical tube, and the draw sliding tube is fixed to the draw sliding support On the upper side, the sliding sleeve is inserted and slides along the sliding sleeve. After the transverse cross tubes are hinged in pairs at the middle, their lower ends are respectively hinged to the transverse hinges fixed on the vertical tubes on both sides of the transverse direction, and their upper ends are respectively hinged to the sliding supports on both sides of the transverse direction. When the corresponding folding device on the longitudinal surface is operated to fold, the push-pull tube B or the push-pull tube C is pushed, thereby pushing up the sliding support. Under the action of the transverse cross tube, the foldable push-pull vehicle is folded and unfolded in the transverse direction. The transverse composite cross folding device includes: transverse horizontal cross tube A (60), transverse horizontal cross tube B (61), The transverse oblique cross tube A (62), the transverse oblique cross tube B (63), the transverse horizontal rigid hinge (78), the oblique rigid hinge (79), one end of the transverse horizontal cross tube A is fixed to the transverse horizontal rigid hinge or other rigid hinge device, one end of the transverse horizontal cross tube B is hinged to the hinge point (78.1) of the transverse horizontal rigid hinge or other rigid hinge device, the other ends of the transverse horizontal cross tube A and the transverse horizontal cross tube B are respectively hinged to the angular side sliding sleeves on the vertical tubes on both sides, the middle parts of the transverse oblique cross tube A and the transverse oblique cross tube B are respectively hinged to the transverse horizontal cross tube A and the transverse horizontal cross tube A. The middle part of tube B is hinged, and the upper end fixing device of the transverse oblique cross tube A is provided with an oblique rigid hinge. The upper end of the transverse oblique cross tube B is hinged to the hinge point (79.1) on the rigid hinge. The lower ends of the transverse oblique cross tube A and the transverse oblique cross tube B are respectively hinged to the transverse hinges fixed on the vertical tubes on both sides of the transverse direction. When the corresponding folding device on the longitudinal surface is operated to fold, the angular sliding sleeve is pushed, thereby pushing the transverse horizontal cross tube A and the transverse horizontal cross tube B to move upward along the vertical tube. Under the action of the composite cross motion, the foldable push-pull cart can be folded and unfolded in the transverse direction.The transverse side sliding cross folding device comprises: an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a transverse cross push tube (83), and a horizontal tube hinge support (44). After one end of the transverse horizontal tube A is hinged to the transverse horizontal tube B via a rigid hinge device, both sides of the transverse cross push tubes are hinged to the upper end of the vertical tube or to the upper support (57) and the lower support (58) fixed on the vertical tube. After the transverse cross push tubes are cross-hinged in pairs in the middle, the lower ends are hinged to the angular side sliding sleeves on the vertical tubes on both sides respectively. The upper ends of the two transverse cross push tubes are hinged to the transverse horizontal tube A and the transverse horizontal tube B, either directly, or via a b-shaped hinge, or via a horizontal tube hinge support. When the corresponding folding device on the longitudinal surface is operated to fold, the angular sliding sleeve is pushed, thereby pushing up the transverse horizontal tube A and the transverse horizontal tube B, and at the same time driving the transverse cross push tube to rotate upward, thereby realizing the folding and unfolding of the foldable push-pull vehicle in the transverse direction. When folding the foldable cart, the upper longitudinal tube A and the upper longitudinal tube B are simultaneously lifted upward at the rigid hinges on the longitudinal surface and rotated around the rigid hinges. Due to the different combinations of these thirteen longitudinal and transverse folding devices, the three-dimensional dimensions of the foldable cart can be changed in three directions, allowing it to fold into a stick shape in different folding methods. When unfolding the foldable cart, the upper longitudinal tube A and the upper longitudinal tube B are pulled apart around the rigid hinges. Under the action of gravity, the foldable cart automatically unfolds and the rigid hinges are self-locking after passing the dead point, achieving the unfolded state.

[0122] refer to Figures 1 to 45 , Figure 46 , Figure 47 , Figure 52 , Figure 53 , Figures 58 to 60 , Figures 62 to 83 , Figure 86 , Figure 87 , Figure 89 , Figure 92 , Figures 96 to 98, the specific implementation of the further scheme of the two independent foldable push-pull carts is: the rigid hinge device includes: rigid hinge A (14), rigid hinge B (16), pad (15), rigid hinge C (18), rigid hinge D (19), rigid hinge member (17), hinge support (39), rigid hinge E (47), rigid hinge J (49), rigid hinge G (78), rigid angle hinge (79), each rigid hinge A, rigid hinge B, rigid hinge C, The rigid hinge D, the rigid hinge part, the rigid hinge E, the rigid hinge J, the rigid hinge G, and the rigid angle hinge are respectively fixed to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or to the middle U-shaped horizontal tube; respectively fixed to the upper longitudinal tube A and the upper longitudinal tube B, or to the lower longitudinal tube A and the lower longitudinal tube B, or to the middle longitudinal tube and the middle transverse tube, or to the transverse horizontal tube A and the transverse horizontal tube B, and then, through The corresponding hinge holes (17.1, 18.1, 39.1, 47.1, 78.1, 79.1) on the rigid hinge device are hinged, wherein the hinge hole (17.1) is hinged directly or hinged via a hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge part in the shape of an oblong hole (39.1) or is hinged to the hinge hole (17.1) of the rigid hinge part in the shape of a round hole; the rigid hinge part is hinged to the hinge hole (17.1) of the rigid hinge part in the shape of a round hole; The hinge device is provided with a rigid hinge clamping groove (32). When the foldable push-pull cart is in an unfolded state, each clamped pipe section (31) will fall into the rigid hinge clamping groove (32). Each clamped pipe section (31) is rigidly clamped, so that the pipes hinged in pairs by the rigid hinge device are completely rigidly hinged. A mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device to reduce friction during rigid hinge clamping and reduce damage to each clamped pipe section.

[0123] refer to Figures 1 to 45 , Figures 55 to 57 , Figures 62 to 83 , Figure 86 , Figure 89 , Figure 93 , Figure 94 , Figure 96 , Figure 98, the specific implementation method of the further scheme of the two independent foldable push-pull carts is: the fixed handle (23) is either fixed to the ends of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or respectively fixed to the outside of the transverse horizontal tube A and the transverse horizontal tube B; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing member (24.5), a latch (24.6), a positioning pin hole (24.7), the handle is connected and fixed to the upper end of the handle rod, and the semicircular transition sleeves in a group of two are symmetrically connected by positioning pins. The hole is fixed at the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B. The other two semicircular rotating sleeves in a group wrap around the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece on the outside, and rotate around the semicircular transition sleeve together. After the fixing piece and the semicircular rotating sleeve are fixedly connected, they are connected and fixed to the lower end of the handle rod, so that the handle device A can rotate freely around the end pipe axis of the lower U-shaped horizontal tube A or the end pipe axis of the lower U-shaped horizontal tube B. The tongue (24.6) is fixed at the middle of the handle rod and is used to fix the handle device A after it is folded; the handle device B (38) includes: a handle (24.1) , handle rod (24.2), or fixed support (68), or sliding support A (69), or sliding support B (76), the handle is installed at the upper end of the handle rod, one side of the fixed support (68) is hinged to the horizontal rigid hinge point on the horizontal cross tube A and the horizontal cross tube B, or is hinged to the rigid support hinge point on the rigid support tube A and the rigid support tube B, and the other end is hinged to the lower end of the handle rod; a slideway (69.1) is provided in the middle of the sliding support A, which is assembled on the middle cross hinge point of the horizontal cross tube or the horizontal cross push tube, and can slide up and down along the slideway, and the entire sliding support A The two horizontal cross tubes or two horizontal cross push tubes are clamped, and the sliding support armor is hinged to the lower end of the handle rod at the hinge hole (69.3). A clamping spring piece (69.2) is provided above the hinge hole where the sliding support armor is hinged to the handle rod. When the foldable push-pull cart is unfolded, the sliding support armor can be cross-limited by the unfolded horizontal cross tubes or horizontal cross push tubes, so as to prevent the handle and the handle rod from rotating around the cross hinge point of the horizontal cross tubes or the horizontal cross push tubes, and can clamp the handle rod to fix it vertically. When the foldable push-pull cart is folded, the handle and the handle rod can slide down to an appropriate position and be clamped and fixed, so that the handle and the handle rod are not too high. A slideway (76.1) is provided in the middle of the sliding support B and is assembled on the middle cross hinge point of the transverse cross tube or the transverse cross push tube. The sliding support B can slide up and down along the slideway. The sliding support B clamps one of the two transverse cross tubes or the two transverse cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod.When the foldable push-pull cart is unfolded, the sliding support B can be cross-limited by the limit piece and the unfolded transverse cross tube or transverse cross push tube, so as to prevent the handle and the handle rod from rotating around the cross hinge point of the transverse cross tube or the transverse cross push tube, and can clamp the handle rod to fix it vertically. When the foldable push-pull cart is folded, the handle and the handle rod can slide down to the appropriate position and be clamped to fix it, so that the handle and the handle rod are not too high.

[0124] refer to Figures 1 to 45 and Figure 56 , Figure 57 , Figures 62 to 83 The specific implementation of the further scheme of the two independent foldable push-pull carts is as follows: the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or are located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7), thereby increasing the loading capacity of the foldable push-pull cart.

[0125] refer to Figures 1 to 45 and Figure 47 , Figure 49 , Figure 60 , Figures 62 to 83 The specific implementation of the further scheme of the two independent foldable push-pull carts is as follows: the panel (21) is made of rigid material, plugged into or fixed to the upper U-shaped horizontal tube A, the upper U-shaped horizontal tube B, the lower U-shaped horizontal tube A, the lower U-shaped horizontal tube B, or the inner side of the middle U-shaped horizontal tube; used as a flat plate for placing transported items. The flexible fabric (28), the braided ribbon (46), and the diagonally crossed ropes (84) are made of flexible material, or made into concave pockets and installed on the foldable push-pull cart truss; or fixed to the foldable push-pull cart in the form of a ribbon braid, the ribbon braiding is either a single longitudinal or transverse braiding method, or a cross braiding method; or fixed to the four corners of the foldable push-pull cart in the form of a diagonally crossed rope.

[0126] refer to Figure 8 , Figure 9 , Figure 11 , Figure 14 , Figure 15 , Figure 17 , Figure 20 , Figures 28 to 31 , Figure 37 , Figure 38 , Figure 47 , Figure 58 , Figure 68 , Figure 69 , Figure 71 , Figure 72 , Figures 75 to 77 , Figures 80 to 83 , Figure 92 The specific implementation of the further solution of the two independent foldable push-pull carts is as follows: the vertical tube belt A (7) and the vertical tube belt B (8) are either made of a rigid material, such as metal or plastic pipes, or a flexible material, such as steel wire, ribbon, cloth strip, rope, etc. The main function of using the flexible material is that when folding, a moving component is required to link the foldable push-pull cart truss to move, and when unfolding, the movement of the linked foldable push-pull cart truss is generally driven by gravity.

[0127] The above is only an implementation scheme of the present invention. It should be pointed out that for ordinary technicians in this field, improvements can be made without departing from the inventive concept of the present invention, but these all fall within the scope of protection of the present invention.

Claims

1. Foldable push-pull cart, including: Upper U-shaped horizontal pipe A (1), upper U-shaped horizontal pipe B (2), lower U-shaped horizontal pipe A (3), lower U-shaped horizontal pipe B (4), middle U-shaped horizontal pipe (5), vertical U-shaped pipe (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), support (25), push-pull pipe (26), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), a side-fixed connecting tube folding device (27, 41, 42, 43, 44, 45), a fixed handle (23), a handle device A (24), a flexible fabric (28), a panel (21), a universal wheel (22), and also includes: a transverse tube (20), an eccentric hinge (35), a supporting sleeve (37), and a braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two left-right symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or hinged by a rigid hinge device, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two ends. A vertical tube device (40) or a hinged multi-layer end vertical tube device (30) is installed on the longitudinal surface of the foldable push-pull vehicle, and a side fixed tube folding device (27, 41, 42, 43, 44, 45) is installed. The side fixed tube folding device comprises: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), a horizontal tube hinge support (44), and a hinge (45). One end of the connecting rod A (41) is directly hinged to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2), or is hinged to the horizontal tube hinge support (44) fixed on the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2), and the other end is hinged to the vertical U-shaped tube (6) or the upper U-shaped horizontal tube B (6) on the opposite side. The invention relates to a foldable push-pull cart, wherein the foldable push-pull cart is directly hinged or hinged via a vertical tube hinge support (43) fixed on the vertical U-shaped tube, the upper end of the connecting rod B (42) is directly hinged to the middle part of the connecting rod A (41) or hinged via a hinge (45), and the lower end of the connecting rod B is directly hinged to the lower U-shaped horizontal tube A (3) or the lower U-shaped horizontal tube B (4) on the same side of the vertical U-shaped tube hinged to the connecting rod A (41), or hinged via a b-shaped hinge; different foldable push-pull carts are equipped with a fixed handle (23) or a handle device A (24), a universal wheel (22) is fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the vertical tube device at the end of two layers, or fixed to the lower end of the vertical tube device at the end of multiple layers, and the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is connected to the vertical U-shaped tube, the two layers, or the lower U-shaped horizontal tube B. The end vertical tube device and the multi-layer end vertical tube device are hinged, either directly or through an eccentric hinge (35). The central U-shaped horizontal tube (5) is hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged through a supporting sleeve (37). The transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. The foldable push-pull cart for different purposes uses either a hard panel (21) or a flexible fabric (28), or both flexible fabrics and braided ribbons (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4). The multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle section connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle section connecting piece is fixed to the other end of the segmented pipes of the upper and lower parts respectively, or is fixed to the other end of the segmented pipes of the upper and lower parts respectively and fixed to both ends of the segmented pipes in the middle of more than four layers at the same time. The semicircular sleeves are symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the U-shaped bottom edges of the middle U-shaped horizontal pipe after being hinged by a rigid hinge device. The upper connecting piece, the lower connecting piece and the middle section connecting piece are sleeved on the semicircular sleeve. The semicircular sleeve has flanges (30.7) at both ends; the two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B after being hinged by the rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends; the rigid hinge device includes: a rigid hinge A (14), a rigid hinge B (16), a gasket (15), rigid hinge C (18), rigid hinge D (19), rigid hinge member (17), hinge support (39), each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, rigid hinge member (17), are respectively fixed to upper U-shaped horizontal tube A (1) and upper U-shaped horizontal tube B (2), or to lower U-shaped horizontal tube A (3) and lower U-shaped horizontal tube B (4), or to middle U-shaped horizontal tube (5), and are hinged through corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge is hinged to the hinge hole (17.1) either directly or through the hinge support (39); the hinge support is in the shape of an oblate hole (39.1) and the rigid hinge. The hinge hole (17.1) of the connecting member (17) is hinged, or is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a circular hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) is provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is fixed to the ends of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is fixed to the outer sides of the transverse horizontal tube A and the transverse horizontal tube B respectively; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing member (24.5), a latch (24.6), a positioning pin hole (24.7), a handle (24.1) and an upper end of a handle rod (24.2) are connected and fixed, a set of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7), and another set of two semicircular rotating sleeves (24.4) are wrapped around the fixed semicircular sleeves on the inner side. The circular transition sleeve is fixedly wrapped by the fixing piece (24.5) on the outside and rotates together around the semicircular transition sleeve. After the fixing piece and the semicircular rotating sleeve are fixedly connected, they are connected and fixed to the lower end of the handle rod. The latch (24.6) is fixed to the middle of the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart. The arrangement of the fifth and more universal wheels is as follows: The panel (21) is symmetrically arranged and installed with the four universal wheels, or located in the middle of the horizontal tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and is hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical tube belt B (8) or the vertical tube belt A (7); the panel (21) is made of rigid material, plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of flexible material, or are installed in a concave pocket shape on the foldable push-pull cart truss; or are fixed to the foldable push-pull cart in a ribbon braiding manner, the ribbon braiding is either a single longitudinal or transverse braiding manner, or a cross braiding manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner.

2. Foldable push-pull cart, including: Upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), vertical tube belt A (7), vertical tube belt B (8), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), vertical tube folding device (7, 8, 41, 43, 44) in the side fixed connecting tube, fixed handle (23), handle device A (24), flexible fabric (28), panel (21), universal wheel (22), and also includes: transverse tube (20), eccentric hinge (35), supporting sleeve (37), braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two left-right symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or hinged with a rigid hinge device, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two sides. The invention relates to a vertical tube device (40) at the end of a layer, or a hinged multi-layer vertical tube device (30) at the end of a layer, and a vertical tube folding device (7, 8, 41, 43, 44) in a side-fixed connecting tube is installed on the longitudinal surface of the foldable push-pull vehicle. The vertical tube folding device (7, 8, 41, 43, 44) in the side-fixed connecting tube comprises: a vertical tube belt A (7), a vertical tube belt B (8), a connecting rod A (41), a vertical tube hinge support (43), a horizontal tube hinge support (44), and one end of the connecting rod A (41) is directly hinged to the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2), or is hinged to it through a b-shaped hinge, or is fixed on the upper U-shaped horizontal tube A (1) or the upper U-shaped horizontal tube B (2). The U-shaped horizontal tube A (1) or the horizontal tube hinge support (44) on the upper U-shaped horizontal tube B (2) is hinged, and the other end is hinged to the vertical U-shaped tube (6) on the opposite side, or is hinged via the vertical tube hinge support (43) fixed on the vertical U-shaped tube, or is hinged to it via a b-shaped hinge. One end of the vertical tube belt A (7) or the vertical tube belt B (8) is hinged to the hinge point of the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), and the other end is hinged to the hinge point of the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) or the middle hinge point of the two middle U-shaped horizontal tubes.Different foldable push-pull carts are either equipped with a fixed handle (23) or a handle device A (24); the universal wheel (22) is either fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device; the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged to the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device, or is directly hinged or hinged via an eccentric hinge (35); the middle U-shaped horizontal tube (5) is either directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged via a support sleeve (37 ) sliding hinge, the transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. Foldable push-pull carts for different purposes use either a hard panel (21), or a flexible fabric (28), or both a flexible fabric and a braided ribbon (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4); the multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle connecting piece is fixed to the other end of the upper and lower segmented pipes respectively, or is fixed to the other end of the upper and lower segmented pipes respectively and fixed to both ends of the middle segmented pipes of more than four layers at the same time. The semicircular sleeve is symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the middle U-shaped horizontal pipe after being hinged by the rigid hinge device. The upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and there are convex ribs at both ends of the semicircular sleeve. The two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, and the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B after being hinged via a rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends.The rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39). Each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are hinged through corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge is hinged to the hinge hole (17.1), or Direct hinge, or hinge through hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is either fixed to the ends of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, or respectively fixed to the horizontal horizontal pipe A and the horizontal horizontal pipe B. Towards the outside of the horizontal tube B; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing piece (24.5), a latch (24.6), a positioning pin hole (24.7), the handle (24.1) and the upper end of the handle rod (24.2) are linked and fixed, and a group of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7), and another group of two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece (24.5) on the outside, and together surround The semicircular transition sleeve rotates, and the fixing member is fixedly connected to the semicircular rotating sleeve and then connected and fixed to the lower end of the handle rod, and the latch (24.6) is fixed to the middle of the handle rod; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, and the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7);The panel (21) is made of a rigid material and is plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of a flexible material and are either arranged in a concave pocket shape on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon braiding manner, the ribbon braiding being either a single longitudinal or transverse braiding manner or a cross braiding manner; or are fixed to the four corners of the foldable push-pull truss in a diagonally crossed manner; the vertical tube belt A (7) and the vertical tube belt B (8) are either made of a rigid material or a flexible material.

3. Foldable push cart, including: Upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), support (25), push-pull tube (26), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), side sliding folding device (9, 10, 13, 25, 26, 27, 29, 44), fixed handle (23), handle device A (24), flexible fabric (28), panel (21), universal wheel ( 22), further comprising: a transverse tube (20), an eccentric hinge (35), a supporting sleeve (37), and a braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two-layer end vertical tube device (40), or hinged to the multi-layer end vertical tube device (30), and on the longitudinal surface of the foldable push-pull cart, the side sliding folding device is installed. Device (9, 10, 13, 25, 26, 27, 29, 44), the side sliding folding device comprises: an upper side push-pull tube (9), a lower side push-pull tube (10), a side sliding sleeve (13), a b-shaped hinge (27), a limiter (29), or comprises: a support (25), a push-pull tube (26), a horizontal tube hinge support (44), one end of the upper side push-pull tube is directly hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is hinged to them via a b-shaped hinge, or via a horizontal tube hinge support, and the other end is hinged to the side sliding sleeve (13) installed on the vertical U-shaped tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30), and the lower side push-pull tube is hinged to the side sliding sleeve (13) installed on the vertical U-shaped tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30). One end of the push-pull tube is hinged to a side sliding sleeve installed on a vertical U-shaped tube (6), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30), and the other end is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or hinged to them via a b-shaped hinge. A push-pull tube (26) is hinged in the middle of the upper side push-pull tube (9) or the lower side push-pull tube (10), and the other end of the push-pull tube is directly hinged to the middle U-shaped horizontal tube (5), or hinged to it via a support (25). A limiter (29) is installed in the middle of the vertical U-shaped tube, or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30) to limit the maximum sliding position of the side sliding sleeve;Different foldable push-pull carts are either equipped with a fixed handle (23) or a handle device A (24); the universal wheel (22) is either fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device; the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged to the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device, or is directly hinged or hinged via an eccentric hinge (35); the middle U-shaped horizontal tube (5) is either directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged via a support sleeve (37 ) sliding hinge, the transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device; the foldable push-pull cart for different purposes adopts either a hard panel (21) or a flexible fabric (28), or both flexible fabrics and braided ribbons (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4); the multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6) The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle connecting piece is fixed to the other end of the upper and lower segmented pipes respectively, or is fixed to the other end of the upper and lower segmented pipes respectively and fixed to both ends of the middle segmented pipes of more than four layers at the same time. The semicircular sleeve is symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the middle U-shaped horizontal pipe after being hinged by the rigid hinge device. The upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and there are convex ribs at both ends of the semicircular sleeve. The two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, and the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B after being hinged via a rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends.The rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39). Each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are hinged through corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein, through the hinge with the hinge hole (17.1), or It is directly hinged or hinged via a hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) falls into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) is provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is fixed to the ends of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, or is fixed to the horizontal horizontal pipe A and the horizontal horizontal pipe B respectively. The outside of the horizontal tube B; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing piece (24.5), a latch (24.6), a positioning pin hole (24.7), the handle (24.1) and the upper end of the handle rod (24.2) are linked and fixed, and a group of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7), and another group of two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece (24.5) on the outside, and together surround The semicircular transition sleeve rotates, and the fixing member is fixedly connected to the semicircular rotating sleeve and then connected and fixed to the lower end of the handle rod, and the latch (24.6) is fixed to the middle of the handle rod; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, and the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7);The panel (21) is made of rigid material and is plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of flexible material and are either arranged in a concave pocket shape on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon braiding manner, the ribbon braiding being either a single longitudinal or transverse braiding manner or a cross braiding manner; or are fixed to the four corners of the foldable push-pull truss in a diagonally crossed manner.

4. Foldable push-pull cart, including: Upper U-shaped horizontal pipe A (1), upper U-shaped horizontal pipe B (2), lower U-shaped horizontal pipe A (3), lower U-shaped horizontal pipe B (4), middle U-shaped horizontal pipe (5), vertical U-shaped pipe (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), a rotating folding device (9, 10, 27, 33, 34, 36), a fixed handle (23), a handle device A (24), a flexible fabric (28), a panel (21), a universal wheel (22), and also includes: a transverse tube (20), an eccentric hinge (35), a supporting sleeve (37), and a braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two left-right symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or hinged by a rigid hinge device, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two ends. A vertical tube device (40) or a hinged multi-layer end vertical tube device (30) is installed on the longitudinal surface of the foldable push-pull vehicle, and a rotating folding device (9, 10, 27, 33, 34, 36) is installed. The rotating folding device comprises: an upper push-pull tube (9), a lower push-pull tube (10), a b-shaped hinge (27), a rotating rod (33), a limit block (34), and a connecting piece (36). One end of the left and right upper push-pull tubes is respectively hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B or directly or through the b-shaped hinge, and the other end is hinged to one end of the rotating rod (33). The other end of the rotating rod is hinged to the vertical U-shaped tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30). The left One end of the two right lower side push-pull tubes (10) is directly hinged to the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B or hinged to them via a b-shaped hinge, and the other end is provided with a limit block (34) and hinged to the upper side push-pull tube hinge point at the same point or at a different point; different foldable push-pull carts are provided with either a fixed handle (23) or a handle device A (24); the universal wheel (22) is fixed to the lower end of the vertical U-shaped tube, or to the lower end of the two-layer end vertical tube device, or to the lower end of the multi-layer end vertical tube device; the hinge connection between the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B and the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device is either directly hinged or hinged via an eccentric hinge (35); the middle U The horizontal tube (5) is directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged by sliding through a supporting sleeve (37). The transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. The foldable push-pull cart for different purposes can use either a hard panel (21) or a flexible fabric (28), or both flexible fabrics and braided ribbons (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4); the multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), a limit pin (30.6), the upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle connecting piece is fixed to the other ends of the upper and lower segmented pipes respectively, or is fixed to the other ends of the upper and lower segmented pipes respectively and fixed to both ends of the middle segmented pipes of more than four layers at the same time, the semicircular sleeve is symmetrically installed and fixed by a limit pin on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the middle U-shaped horizontal pipe after being hinged by a rigid hinge device, the upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends; the two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece ( 30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight tube, and the lower connecting piece is fixed to the other end of the straight tube. The semicircular sleeve is symmetrically installed and fixed by a limit pin on the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B after being hinged by the rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the two ends of the semicircular sleeve have flanges (30.7); the rigid hinge device includes: rigid hinge A (14), rigid hinge B (16), a pad (15), rigid hinge C (18), rigid hinge D (19), a rigid hinge member (17), an articulated support (39), and each rigid hinge Hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to upper U-shaped horizontal tube A (1) and upper U-shaped horizontal tube B (2), or to lower U-shaped horizontal tube A (3) and lower U-shaped horizontal tube B (4), or to middle U-shaped horizontal tube (5), and are hinged via corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge connection with the hinge hole (17.1) is either direct hinge connection or hinge connection via a hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblate hole (39.1), or is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a circular hole. ; A rigid hinged clamping groove (32) is provided on the rigid hinged device, and each clamped pipe section (31) will fall into the rigid hinged clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) is provided on the rigid hinged clamping groove of the rigid hinged device; the fixed handle (23) is fixed to the ends of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, or is fixed to the outer sides of the transverse horizontal tube A and the transverse horizontal tube B respectively; the handle device A (24) comprises: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing member (24.5), a latch (24.6), a positioning pin hole (24.7), a handle (24.1) is connected and fixed with the upper end of the handle bar (24.2); a group of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7); another group of two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing member (24.5) on the outside, and rotate around the semicircular transition sleeve together; after the fixing member is fixedly connected with the semicircular rotating sleeve, it is connected and fixed to the lower end of the handle bar; the latch (24.6) is fixed to the middle part of the handle bar; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located at the four corners of the foldable push-pull cart. The middle part of the transverse tube (20) of the wheel plane, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull vehicle, is hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical tube belt B (8) or the vertical tube belt A (7); the panel (21) is made of rigid material, plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of flexible material, or are installed in a concave pocket shape on the foldable push-pull vehicle truss; or are fixed to the foldable push-pull vehicle in a ribbon braiding manner, and the ribbon braiding is either a single longitudinal or transverse braiding manner, or a cross-braiding manner; or are fixed to the four corners of the foldable push-pull vehicle in a diagonal cross-rope manner.

5. Foldable push cart, including: Upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), vertical tube belt A (7), vertical tube belt B (8), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), cross tube vertical tube folding device (7, 8, 27, 44, 77), fixed handle (23), handle device A (24), flexible fabric (28), panel (2 1), universal wheel (22), also includes: transverse tube (20), eccentric hinge (35), supporting sleeve (37), braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two left-right symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two-layer end vertical tube device (40), or hinged to the multi-layer end vertical tube device (30), in A cross-tube vertical tube folding device (7, 8, 27, 44, 77) is installed on the longitudinal surface of the foldable push-pull cart. The cross-tube vertical tube folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge support (44), a longitudinal cross tube (77), and the longitudinal cross tube (77) is arranged in a symmetrical projection or mirror image cross pattern in parallel planes on both sides of the longitudinal direction, or is arranged in a single oblique direction in a plane on one side of the longitudinal direction. One end of the longitudinal cross tube is directly hinged to the upper U-shaped horizontal tube A or the upper U-shaped horizontal tube B, or is hinged to it through the horizontal tube hinge support (44) or through the b-shaped hinge, and the other end is hinged to the opposite U-shaped horizontal tube. The lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B on the side is directly hinged or hinged with it via a b-shaped hinge. The middle parts of the symmetrically arranged longitudinal cross tubes do not need to be hinged with each other. The upper end of the vertical tube belt B is hinged with the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the lower end of the vertical tube belt B is hinged with the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B. After the two ends of the vertical tube belt A are hinged with the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B and the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, the middle part of the vertical tube belt A is hinged with the middle hinge point of the two middle U-shaped horizontal tubes (5);Different foldable push-pull carts are either equipped with a fixed handle (23) or a handle device A (24); the universal wheel (22) is either fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device; the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged to the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device, or is directly hinged or hinged via an eccentric hinge (35); the middle U-shaped horizontal tube (5) is either directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged via a support sleeve (37 ) sliding hinge, the transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. Foldable push-pull carts for different purposes use either a hard panel (21), or a flexible fabric (28), or both a flexible fabric and a braided ribbon (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4); the multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle connecting piece is fixed to the other end of the upper and lower segmented pipes respectively, or is fixed to the other end of the upper and lower segmented pipes respectively and fixed to both ends of the middle segmented pipes of more than four layers at the same time. The semicircular sleeve is symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the middle U-shaped horizontal pipe after being hinged by the rigid hinge device. The upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and there are convex ribs at both ends of the semicircular sleeve. The two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, and the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B after being hinged via a rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends.The rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39). Each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are hinged through corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge is hinged to the hinge hole (17.1), or Direct hinge, or hinge through hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is either fixed to the ends of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, or respectively fixed to the horizontal horizontal pipe A and the horizontal horizontal pipe B. Towards the outside of the horizontal tube B; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing piece (24.5), a latch (24.6), a positioning pin hole (24.7), the handle (24.1) and the upper end of the handle rod (24.2) are linked and fixed, and a group of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7), and another group of two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece (24.5) on the outside, and together surround The semicircular transition sleeve rotates, and the fixing member is fixedly connected to the semicircular rotating sleeve and then connected and fixed to the lower end of the handle rod, and the latch (24.6) is fixed to the middle of the handle rod; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, and the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7);The panel (21) is made of a rigid material and is plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of a flexible material and are either arranged in a concave pocket shape on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon braiding manner, the ribbon braiding being either a single longitudinal or transverse braiding manner or a cross braiding manner; or are fixed to the four corners of the foldable push-pull truss in a diagonally crossed manner; the vertical tube belt A (7) and the vertical tube belt B (8) are either made of a rigid material or a flexible material.

6. Foldable push-pull cart, including: Upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), vertical tube belt A (7), vertical tube belt B (8), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), middle vertical tube side sliding folding device (7, 8, 9, 13, 27, 44), fixed handle (23), handle device A ( 24), flexible fabric (28), panel (21), universal wheel (22), and also includes: transverse tube (20), eccentric hinge (35), supporting sleeve (37), braided ribbon (46), characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device, and the two left-right symmetrically arranged middle U-shaped horizontal tubes (5) are hinged to each other, or hinged with a rigid hinge device, or not hinged, and their two sides are either hinged to the vertical U-shaped tube (6), or hinged to the two layers. An end vertical tube device (40), or an articulated multi-layer end vertical tube device (30), is installed on the longitudinal surface of the foldable push-pull vehicle with a middle vertical tube side sliding folding device (7, 8, 9, 13, 27, 29, 44), wherein the middle vertical tube side sliding folding device comprises: a vertical tube belt A (7), a vertical tube belt B (8), an upper side push-pull tube (9), a side sliding sleeve (13), a b-shaped hinge (27), a limiter (29), and a horizontal tube hinge support (44). One end of the left and right upper side push-pull tubes (9) is respectively articulated with the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B or directly articulated, or The horizontal tube is hingedly supported (44) or hinged therewith via a b-shaped hinge, and the other end is hinged to a side sliding sleeve (13) installed on a vertical U-shaped tube (6), or a two-layer vertical riser tube device (40), or a multi-layer vertical riser tube device (30). A limiter (29) is installed in the middle of the vertical U-shaped tube, or the two-layer vertical riser tube device (40), or the multi-layer vertical riser tube device (30) to limit the maximum sliding position of the side sliding sleeve. The two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge point of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge point of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B.Different foldable push-pull carts are either equipped with a fixed handle (23) or a handle device A (24); the universal wheel (22) is either fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device; the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged to the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device, or is directly hinged or hinged via an eccentric hinge (35); the middle U-shaped horizontal tube (5) is either directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is hinged via a support sleeve (37 ) sliding hinge, the transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. Foldable push-pull carts for different purposes use either a hard panel (21), or a flexible fabric (28), or both a flexible fabric and a braided ribbon (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4); the multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2), a middle connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle connecting piece is fixed to the other end of the upper and lower segmented pipes respectively, or is fixed to the other end of the upper and lower segmented pipes respectively and fixed to both ends of the middle segmented pipes of more than four layers at the same time. The semicircular sleeve is symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the middle U-shaped horizontal pipe after being hinged by the rigid hinge device. The upper connecting piece, the lower connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and there are convex ribs at both ends of the semicircular sleeve. The two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe. The semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, and the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B after being hinged via a rigid hinge device. The upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and the semicircular sleeve has flanges (30.7) at both ends.The rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39). Each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are hinged through corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge is hinged to the hinge hole (17.1), or Direct hinge, or hinge through hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is either fixed to the ends of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, or respectively fixed to the horizontal horizontal pipe A and the horizontal horizontal pipe B. Towards the outside of the horizontal tube B; the handle device A (24) includes: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing piece (24.5), a latch (24.6), a positioning pin hole (24.7), the handle (24.1) and the upper end of the handle rod (24.2) are linked and fixed, and a group of two semicircular transition sleeves (24.3) are symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7), and another group of two semicircular rotating sleeves (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece (24.5) on the outside, and together surround The semicircular transition sleeve rotates, and the fixing member is fixedly connected to the semicircular rotating sleeve and then connected and fixed to the lower end of the handle rod, and the latch (24.6) is fixed to the middle of the handle rod; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, and the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7);The panel (21) is made of a rigid material and is plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of a flexible material and are either arranged in a concave pocket shape on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon braiding manner, the ribbon braiding being either a single longitudinal or transverse braiding manner or a cross braiding manner; or are fixed to the four corners of the foldable push-pull truss in a diagonally crossed manner; the vertical tube belt A (7) and the vertical tube belt B (8) are either made of a rigid material or a flexible material.

7. Foldable push-pull cart, including: Upper U-shaped horizontal tube A (1), upper U-shaped horizontal tube B (2), lower U-shaped horizontal tube A (3), lower U-shaped horizontal tube B (4), middle U-shaped horizontal tube (5), vertical U-shaped tube (6), or two-layer vertical riser device (40), or multi-layer vertical riser device (30), vertical tube belt A (7), vertical tube belt B (8), rigid hinge device (14, 15, 16, 17, 17.1, 18, 18.1, 19, 39, 39.1), side sliding hinge cross folding device ( 7, 8, 13, 44, 48), a fixed handle (23), a handle device A (24), a flexible fabric (28), a panel (21), a universal wheel (22), and further comprising: a transverse tube (20), an eccentric hinge (35), a supporting sleeve (37), and a braided ribbon (46). The invention is characterized in that the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2) are hinged via a rigid hinge device, and the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4) are hinged via a rigid hinge device. The centrally arranged U-shaped horizontal tubes (5) are hinged to each other by rigid hinge devices or not, and their two sides are hinged to vertical U-shaped tubes (6), or hinged to two-layer end vertical tube devices (40), or hinged to multiple-layer end vertical tube devices (30). On the longitudinal surface of the foldable push-pull cart, a side sliding hinged cross-folding device (7, 8, 13, 27, 44, 48) is installed. The side sliding hinged cross-folding device includes: vertical tube belt A (7), vertical tube belt B (8), side sliding sleeve (13), b-shaped hinge (27), horizontal tube hinge support (44), hinged cross tube (48), one end of the hinged cross tube (48) is hinged to the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B or directly, or hinged to them through the horizontal tube hinge support (44) or b-shaped hinge, and the other end is hinged to the side sliding sleeve (13) installed on the vertical U-shaped tube (6), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30), and the two hinged cross tubes on the same side are hinged to each other in the middle of the tube (48.1), the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper U-shaped horizontal tube A and the upper U-shaped horizontal tube B, and the hinge points of the lower U-shaped horizontal tube A and the lower U-shaped horizontal tube B, or the vertical tube belt A or the vertical tube belt B is not installed; different foldable push-pull carts are either equipped with a fixed handle (23) or a handle device A (24), the universal wheel (22) is either fixed to the lower end of the vertical U-shaped tube, or fixed to the lower end of the two-layer end vertical tube device, or fixed to the lower end of the multi-layer end vertical tube device, the lower U-shaped horizontal tube A or the lower U-shaped horizontal tube B is hinged to the vertical U-shaped tube, the two-layer end vertical tube device, or the multi-layer end vertical tube device, or The invention relates to a foldable push-pull cart, which is directly hinged or hinged via an eccentric hinge (35). The central U-shaped horizontal tube (5) is directly hinged to the vertical U-shaped tubes on both sides, or one side is directly hinged and the other side is slidingly hinged via a supporting sleeve (37). The transverse tube (20) is installed in the middle, and its tube axis is concentric with the axis of the hinge hole of the rigid hinge device. The foldable push-pull cart for different purposes adopts either a hard panel (21) or a flexible fabric (28), or both flexible fabrics and braided ribbons (46) at the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4). The multi-layer end vertical tube device (30) is composed of a segmented tube (30.1), an upper connecting piece (30.2) and a plurality of connecting pieces (30.3). , a middle section connecting piece (30.3), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6). The upper connecting piece is fixed to one end of the upper segmented pipe, the lower connecting piece is fixed to one end of the lower segmented pipe, the middle section connecting piece is fixed to the other end of the segmented pipe of the upper and lower parts respectively, or is fixed to the other end of the segmented pipe of the upper and lower parts respectively, and is fixed to the two ends of the segmented pipe in the middle of more than four layers. The semicircular sleeves are symmetrically installed and fixed by limit pins on the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B, and the U-shaped bottom edges on both sides of the middle U-shaped horizontal pipe after being hinged by a rigid hinge device. The upper connecting piece, the lower The connecting piece and the middle connecting piece are sleeved on the semicircular sleeve, and flanges (30.7) are provided at both ends of the semicircular sleeve; the two-layer end vertical pipe device (40) is composed of a straight pipe (40.1), an upper connecting piece (30.2), a lower connecting piece (30.4), a semicircular sleeve (30.5), and a limit pin (30.6); the upper connecting piece is fixed to one end of the straight pipe, and the lower connecting piece is fixed to the other end of the straight pipe; the semicircular sleeve is symmetrically installed and fixed by the limit pin on the U-shaped bottom edges of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, and the lower U-shaped horizontal pipe A and the lower U-shaped horizontal pipe B after being hinged via a rigid hinge device; the upper connecting piece and the lower connecting piece are sleeved on the semicircular sleeve, and flanges (30.7) are provided at both ends of the semicircular sleeve.7); The rigid hinge device comprises: a rigid hinge A (14), a rigid hinge B (16), a pad (15), a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39). Each rigid hinge A, rigid hinge B, rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the lower U-shaped horizontal tube A (3) and the lower U-shaped horizontal tube B (4), or to the middle U-shaped horizontal tube (5), and are fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the middle U-shaped horizontal tube (5), and are fixed to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (2), or to the upper U-shaped horizontal tube A (1) and the upper U-shaped horizontal tube B (4 ... The hinged connection is performed with the corresponding hinged holes (17.1, 18.1, 39.1) on the connecting device, wherein the hinged connection with the hinged hole (17.1) is either directly hinged or hinged via the hinged support (39); the hinged support is hinged with the hinged hole (17.1) of the rigid hinged member (17) in the shape of an oblong hole (39.1), or is hinged with the hinged hole (17.1) of the rigid hinged member (17) in the shape of a round hole; the rigid hinged device is provided with a rigid hinged clamping groove (32), and each clamped pipe section (31) will fall into the rigid hinged clamping groove ( 32), each clamped pipe section (31) is rigidly clamped; a mounting pad (15) is provided on the rigid hinge clamping groove of the rigid hinge device; the fixed handle (23) is fixed to the ends of the upper U-shaped horizontal pipe A and the upper U-shaped horizontal pipe B, or respectively fixed to the outside of the transverse horizontal pipe A and the transverse horizontal pipe B; the handle device A (24) comprises: a handle (24.1), a handle rod (24.2), a semicircular transition sleeve (24.3), a semicircular rotating sleeve (24.4), a fixing member (24.5), a latch (24.6), a fixed member (24.7), a fixing member (24.8), a fixing member (24.9), a fixing member (24.1), a fixing member (24.2), a fixing member (24.1), a fixing member (24.2), a fixing member (24.3), a fixing member (24.4), a fixing member (24.5), a latch (24.6), a fixing member (24.7), a fixing member (24.8), a fixing member (24.9), a fixing member (24.1 ... The handle (24.1) is connected and fixed to the upper end of the handle rod (24.2) through the positioning pin hole (24.7). The semicircular transition sleeve (24.3) of two pieces is symmetrically fixed to the end of the lower U-shaped horizontal tube A or the end of the lower U-shaped horizontal tube B through the positioning pin hole (24.7). The other two pieces of the semicircular rotating sleeve (24.4) wrap the fixed semicircular transition sleeve on the inside and are fixedly wrapped by the fixing piece (24.5) on the outside. They rotate around the semicircular transition sleeve together. After the fixing piece and the semicircular rotating sleeve are fixedly connected, they are connected and fixed to the lower end of the handle rod. The latch (24.6) is fixed to the middle of the handlebar; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and subsequent universal wheels are arranged symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or are located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and are hinged to the rigid hinge point on the longitudinal rigid hinge device or are directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7); the panel (21) is made of rigid material and is plugged into or fixed to the upper U-shaped horizontal tube A (1), the upper U-shaped horizontal tube B (2), the lower U-shaped horizontal tube A (3), the lower U-shaped horizontal tube B (4), or the inner side of the middle U-shaped horizontal tube (5); the flexible fabric (28) and the braided ribbon (46) are made of flexible material and are either arranged in a concave pocket shape on the foldable push-pull truss; or are fixed to the foldable push-pull truss in a ribbon-woven manner, the ribbon weaving being either a single longitudinal or transverse weaving manner or a cross-weaving manner; or are fixed to the four corners of the foldable push-pull truss in a diagonally crossed manner with ropes; The vertical tube belt A (7) and the vertical tube belt B (8) are made of either rigid material or flexible material.

8. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), middle longitudinal tube (54), middle transverse tube (55), vertical tube (56), upper support (57), lower support (58), middle support (59), transverse horizontal tube A (81), transverse horizontal tube B (82), transverse hinge (66), wheel support (67), support (25), push-pull tube (26), rigid hinge device (17, 18, 19, 47, 49), sliding folding device B (9, 10, 25, 26, 27, 29, 44, 80), or sliding folding device C (9, 10, 25, 26, 27, 29, 44, 80, 81, 82), or The invention relates to a transverse composite cross-folding device (60, 61, 62, 63, 78, 79, 80), a handle device B (38), a flexible fabric (28), a universal wheel (22), and further comprising: an eccentric hinge (35), a braided ribbon (46), and a diagonal cross rope (84). The invention is characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device, and the transverse horizontal tube A (81) and the transverse horizontal tube B (82) are hinged via a rigid hinge device. After the rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each tube are directly hinged to the two ends of the vertical tube (56), or are hinged to the upper support (56) fixed on the vertical tube (56). 7) and the lower support (58) are hinged, and the multi-layer foldable push-pull cart with more than three layers, the middle longitudinal tube and the middle transverse tube are hinged to each other or two by rigid hinge devices, or not hinged, and the other ends of the two middle longitudinal tubes and the middle transverse tubes are hinged to the vertical tube (56) in the middle or directly, or hinged to it through the middle support (59) fixed on the vertical tube (56), and a sliding folding device B (9, 10, 25, 26, 27, 29, 44, 80) is installed on the longitudinal surface of the foldable push-pull cart, and the sliding folding device B includes: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a b-shaped hinge (27), a limiter (29), or further includes: a support (25), a push-pull tube ( 26), a horizontal tube hinge support (44), on the longitudinal surface of the foldable push-pull cart, one end of the upper push-pull tube (9) on the left and right sides is respectively hinged to the upper longitudinal tube A (50) and the upper longitudinal tube B (51) or directly, or hinged via a b-shaped hinge, or hinged therewith via a horizontal tube hinge support, and the other end is respectively hinged to the angular side sliding sleeve (80) installed on the two vertical tubes (56), one end of the lower push-pull tube on the left and right sides is respectively hinged to the angular side sliding sleeve installed on the vertical tube (56), and the other end is respectively hinged to the lower longitudinal tube A and the lower longitudinal tube B or directly, or hinged via a b-shaped hinge, or hinged therewith via a horizontal tube hinge support, in the middle of the upper push-pull tube (9) or the lower push-pull tube (10), or the push-pull tube (26) is hinged,The other end of the push-pull tube is directly hinged to the middle longitudinal tube (54), or hinged to it via a support (25). A limiter (29) is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve. On the transverse surfaces of both ends of the foldable push-pull cart, there are side sliding folding devices C (9, 10, 25, 26, 27, 29, 44, 80, 81, 82), or transverse composite cross folding devices (60, 61, 62, 63, 78, 79, 80). The side sliding folding device C includes: an upper side push-pull tube (9), a lower side push-pull tube (10), an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a b-shaped hinge (27), a limiter (29), a horizontal tube hinge support (44), or further comprising: a support (25), a push-pull tube (26), one end of the upper push-pull tube (9) on the front and rear sides is respectively hinged to the upper horizontal tube A (81) and horizontal tube B (82) or directly hinged, or hinged via a b-shaped hinge, or hinged via a horizontal tube hinge support, and the other end is respectively hinged to the angular side sliding sleeve (80) installed on the two vertical tubes (56), one end of the lower push-pull tube (10) on the front and rear sides is respectively hinged to the angular side sliding sleeve installed on the vertical tube (56), and the other end is respectively hinged to the lower horizontal tube A (81) and horizontal tube B (82) or directly hinged, or hinged via a b-shaped hinge, or hinged via a water pipe hinge support. The horizontal tube hinge support is hinged to it, in the middle of the upper side push-pull tube (9) or the lower side push-pull tube (10), or the hinged push-pull tube (26), the other end of the push-pull tube is directly hinged to the middle horizontal tube (55), or is hinged to it through the support (25), and the limiter (29) is installed in the middle of the vertical tube to limit the maximum sliding position of the angular side sliding sleeve; the horizontal composite cross folding device includes: horizontal cross tube A (60), horizontal cross tube B (61), horizontal oblique cross tube A (62), horizontal oblique cross tube B (63), horizontal rigid hinge (78), rigid angle hinge (79), horizontal rigid hinge (78) or other rigid hinge fixed at one end of horizontal cross tube A (60) The hinge device comprises one end of the horizontal cross tube B (61) being hinged to a hinge point (78.1) of a horizontal rigid hinge (78) or a hinge point on another rigid hinge device, the other ends of the horizontal cross tube A (60) and the horizontal cross tube B (61) being hinged to angular side sliding sleeves (80) on the vertical tubes on both sides, the middle portions of the horizontal oblique cross tube A (62) and the horizontal oblique cross tube B (63) being hinged to the middle portions of the horizontal cross tube A (60) and the horizontal cross tube B (61), the upper end fixing device of the horizontal oblique cross tube A (62) being provided with a rigid angle hinge (79), and the upper end of the horizontal oblique cross tube B (63) being hinged to a hinge point (79.1) on the rigid angle hinge (79).The lower ends of the transverse oblique cross tube A (62) and the transverse oblique cross tube B (63) are respectively hinged to the transverse hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction; the foldable push-pull cart device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), or the transverse horizontal tube A (81), the transverse horizontal tube B (82), and the vertical tube (56) are either directly hinged, or hinged through an eccentric hinge (35), or hinged through an upper support (57) and a lower support (58) fixed to both ends of the vertical tube, the middle longitudinal tube (54) and the middle transverse tube (55) or The foldable push-pull cart is hinged to a middle support (59) fixed in the middle of the vertical tube, or directly hinged to the vertical tubes at four corners, or hinged to the vertical tube on one side and hinged to the vertical tube on the other side via a support sleeve (37). The foldable push-pull cart may be made of a flexible fabric (28), a braided ribbon (46), a diagonally crossed rope (84), a steel wire rope, or a wire mesh, or both flexible fabrics, or braided ribbons (46) or steel wire ropes are arranged transversely on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or braided ribbons or steel wire ropes are arranged in the diagonally crossed direction of the foldable push-pull cart when viewed from above. The rigid hinged device (17, 18, 19, 47, 49, 78, 79) includes: a rigid hinge C (18), The rigid hinge D (19), the rigid hinge member (17), the hinge support (39), the rigid hinge E (47), the rigid hinge H (49), the transverse horizontal rigid hinge (78), the rigid angle hinge (79), each rigid hinge C, the rigid hinge D, the rigid hinge member (17), the rigid hinge E (47), the rigid hinge H (49), the transverse horizontal rigid hinge (78), the rigid angle hinge (79), are respectively fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or to the middle longitudinal tube (54) and the middle transverse tube (55), or to the transverse horizontal tube A (81) and the transverse horizontal tube B (82), and are fixed through the corresponding hinge holes (17.1, 18.1, 39.1, 47.1, 78.1, 79.1) are hinged, wherein the hinged connection is made via the hinge hole (17.1), or directly hinged, or hinged via the hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) falls into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) is provided on the rigid hinge clamping groove of the rigid hinge device; the handle device B (38),The invention comprises a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), wherein the handle is arranged at the upper end of the handle rod, one side of the fixed support (68) is hinged to a hinge point of a horizontal rigid hinge (78) on a horizontal horizontal cross tube A (60) and a horizontal horizontal cross tube B (61), or is hinged to a hinge point of a rigid support (85) on a rigid support tube A (86) and a rigid support tube B (87), and the other end is hinged to the lower end of the handle rod (24.2); the middle part of the sliding support A (69) is provided with a The slideway (69.1) is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), slides up and down along the slideway, and the sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes. The sliding support A is then hinged to the lower end of the handle rod at the hinge hole (69.3), and a clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; the middle part of the sliding support B (76) is provided with a slideway (76.1), assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), slides up and down along the slideway, and the sliding support B clamps the two transverse cross tubes. The cross tube or one of the two horizontal cross push tubes, the sliding support B is hinged to the lower end of the handle rod at the hinge hole (76.3), and a clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod; the foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels, the four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) on the four-wheel plane of the foldable push-pull cart , or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, hinged to the rigid hinge points on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical tube belt B (8) or the vertical tube belt A (7); the flexible fabric (28), braided ribbon (46), and diagonal cross rope (84) are made of flexible materials, or are installed in a concave pocket shape on the foldable push-pull cart truss; or are fixed to the foldable push-pull cart in a ribbon weaving manner, and the ribbon weaving is either a single longitudinal or transverse weaving manner, or a cross weaving manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner. , 9. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), vertical tube (56), upper support (57), lower support (58), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19), side fixed connecting tube folding device (27, 41, 42, 43, 44, 45), four-corner pull rod folding device (27, 70, 71, 72, 73, 74, 75), handle device B (38), flexible fabric (28), universal wheel (22), also includes: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, and the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device. After rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or to the upper support (57) and the lower support fixed on the vertical tube (56). (58) hinged, a side-fixed connecting tube folding device (27, 41, 42, 43, 44, 45) is installed on the longitudinal surface of the foldable push-pull cart, and the side-fixed connecting tube folding device comprises: a b-shaped hinge (27), a connecting rod A (41), a connecting rod B (42), a vertical tube hinge support (43), a horizontal tube hinge support (44), a hinge (45), and one end of the connecting rod A (41) is directly hinged to the upper longitudinal tube A (50) or the upper longitudinal tube B (51), or is hinged via a b-shaped hinge, or is fixed to the upper longitudinal tube A (50). The longitudinal tube A (50) or the horizontal tube hinge support (44) on the upper longitudinal tube B (51) is hinged, and the other end is hinged to the vertical tube (56) on the opposite side or hinged via the vertical tube hinge support (43) fixed on the vertical tube. The upper end of the connecting rod B (42) is hinged to the middle part of the connecting rod A (41) or directly hinged or hinged via a hinge (45). The lower end of the connecting rod B is hinged to the lower longitudinal tube A (50) or the lower longitudinal tube B (51) on the same side of the vertical U-shaped tube hinged to the connecting rod A or directly hinged or hinged via a b-shaped hinge.On the transverse surfaces of both ends of the foldable push-pull cart, a four-corner pull-out rod folding device (27, 70, 71, 72, 73, 74, 75) is installed. The four-corner pull-out rod folding device comprises: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a pull-out sliding support (73), a pull-out sliding sleeve (74), a pull-out sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B (71) is hinged to the connecting rod A, one end of the push-pull tube C (72) is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or directly hinged, or hinged to it through a b-shaped hinge or a horizontal tube hinge support, the other ends of the push-pull tube B (71) and the push-pull tube C (72) are hinged to the pull-out sliding support (73) on the longitudinal plane, and the pull-out sliding sleeve (74) is installed at the upper end of the vertical tube (56), the sliding tube (75) is fixed on the sliding support (73), inserted into the sliding sleeve (74) and slides along the sliding sleeve, and the cross tubes (70) are hinged in pairs at the middle, and their lower ends are respectively hinged to the horizontal hinges (66) fixed on the vertical tubes (56) on both sides of the horizontal direction, and the upper ends are respectively hinged to the sliding supports (73) on both sides of the horizontal direction; the foldable push-pull cart device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), and the vertical tube (56) are either directly hinged, or The foldable push-pull cart is hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of a vertical tube, or adopts a flexible fabric (28), or adopts a braided ribbon (46), or adopts a diagonally crossed rope (84), or a steel wire rope, or a wire mesh, or is configured with a flexible fabric, or also horizontally configures a braided ribbon (46) or a steel wire rope on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or configures a braided ribbon or a steel wire rope in the diagonally crossed direction when viewed from above the foldable push-pull cart; the rigid hinge device (17, 18, 19, 39) includes: a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member ( 17), an articulated support (39), each rigid articulated C, rigid articulated D, and rigid articulated member (17) are respectively fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), and are articulated via corresponding articulated holes (17.1, 18.1, 39.1) on the rigid articulated device, wherein the articulation with the articulated hole (17.1) is either directly articulated or articulated via the articulated support (39); the articulated support is either articulated with the articulated hole (17.1) of the rigid articulated member (17) in the shape of an oblong hole (39.1), or articulated with the articulated hole (17.1) of the rigid articulated member (17) in the shape of a round hole;The rigid hinge device is provided with a rigid hinge clamping groove (32), and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the handle device B (38) includes: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), and the handle is installed at the upper end of the handle rod, one side of the fixed support (68) or the horizontal cross tube A (60) and the horizontal cross tube B (61). The rigid hinge (78) is hinged at a hinge point, or is hinged at a hinge point of the rigid support (85) on the rigid support tube A (86) and the rigid support tube B (87), and the other end is hinged at the lower end of the handle rod (24.2); a slideway (69.1) is provided in the middle of the sliding support A (69), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes, and the sliding support A is then hinged to the lower end of the handle rod at a hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; the sliding support B (76) A slideway (76.1) is provided in the middle part, which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support B clamps the two transverse cross tubes or one of the two transverse cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth universal wheel is installed at the corners of the foldable push-pull cart. The arrangement of more than one universal wheel is symmetrical with the four universal wheels, and is either located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and is hinged to the rigid hinge point on the longitudinal rigid hinge device. The flexible fabric (28), braided ribbon (46), and diagonally crossed rope (84) are made of flexible material, or are installed in a concave pocket shape on the foldable push-pull cart truss; or are fixed to the foldable push-pull cart in a ribbon braiding manner, and the ribbon braiding is either a single longitudinal or transverse braiding manner, or a cross-braiding manner; or are fixed to the four corners of the foldable push-pull cart in a diagonally crossed rope manner.

10. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), vertical tube (56), upper support (57), lower support (58), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19, 39), vertical tube folding device (7, 8, 41, 43, 44) in the side fixed connecting tube, four-corner pull rod folding device (27, 70, 71, 72, 73, 74, 75), handle device B (38), flexible fabric (28) , the universal wheel (22) also includes: an eccentric hinge (35), a braided ribbon (46), a diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, and the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device. After rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or are hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56), and can be A vertical tube folding device (7, 8, 41, 43, 44) is installed on the longitudinal surface of the folding push-pull cart. The vertical tube folding device (7, 8, 41, 43, 44) in the side-fixed connecting tube comprises: a vertical tube belt A (7), a vertical tube belt B (8), a connecting rod A (41), a vertical tube hinge support (43), a horizontal tube hinge support (44), one end of the connecting rod A (41) is directly hinged to the upper longitudinal tube A (50) or the upper longitudinal tube B (51), or is hinged to it through a B-shaped hinge, or is fixed to the upper longitudinal tube A (50) or the upper longitudinal tube B (51). The horizontal tube hinge support (44) on the B (51) is hinged, and the other end is hinged to the vertical tube (56) on the opposite side, or is hinged directly, or is hinged via the vertical tube hinge support (43) fixed on the vertical U-shaped tube, or is hinged thereto via a b-shaped hinge. One end of the vertical tube belt A (7) or the vertical tube belt B (8) is hinged to the hinge point of the upper longitudinal tube A (50) and the upper longitudinal tube B (51), and the other end is hinged to the hinge point of the lower longitudinal tube A (52) and the lower longitudinal tube B (53) or the middle hinge point of the two middle longitudinal tubes (55);On the transverse surfaces of both ends of the foldable push-pull cart, a four-corner pull-out rod folding device (27, 70, 71, 72, 73, 74, 75) is installed. The four-corner pull-out rod folding device includes: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a pull-out sliding support (73), a pull-out sliding sleeve (74), a pull-out sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B (71) is hinged to the connecting rod A, one end of the push-pull tube C (72) is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or directly hinged, or hinged to it through a b-shaped hinge or a horizontal tube hinge support, the other ends of the push-pull tube B (71) and the push-pull tube C (72) are hinged to the pull-out sliding support (73) on the longitudinal plane, and the pull-out sliding The sleeve (74) is installed at the upper end of the vertical tube (56), the sliding tube (75) is fixed on the sliding support (73), inserted into the sliding sleeve (74) and slides along the sliding sleeve, and the cross tubes (70) are hinged in pairs at the middle. Their lower ends are respectively hinged with the horizontal hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction, and their upper ends are respectively hinged with the sliding supports (73) on both sides of the transverse direction; the foldable push-pull cart device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), and the vertical tube (56) or directly hinged, or The foldable push-pull cart is hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of the vertical tube, or adopts a flexible fabric (28), or adopts a braided ribbon (46), or adopts a diagonally crossed rope (84), or a steel wire rope, or a wire mesh, or is configured with a flexible fabric, or also horizontally configures a braided ribbon (46) or a steel wire rope on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or configures a braided ribbon or a steel wire rope in the diagonally crossed direction when viewed from above the foldable push-pull cart; the rigid hinge device (17, 18, 19, 39) includes: a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), each rigid hinge C, rigid hinge D, and rigid hinge member (17) of the hinge support (39) are fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), and are hinged via corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinge connection with the hinge hole (17.1) is either directly hinged or hinged via the hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a circular hole;The rigid hinge device is provided with a rigid hinge clamping groove (32), and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the handle device B (38) includes: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), and the handle is installed at the upper end of the handle rod, and one side of the fixed support (68) is either hinged to the horizontal rigid hinge (78) hinge point on the horizontal horizontal cross tube A (60) and the horizontal horizontal cross tube B (61), or is hinged to the rigid hinge. The rigid support (85) on the rigid support tube A (86) and the rigid support tube B (87) is hinged at a hinge point, and the other end is hinged to the lower end of the handle rod (24.2); a slideway (69.1) is provided in the middle of the sliding support A (69), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes, and the sliding support A is hinged to the lower end of the handle rod at a hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; a slideway (76.1) is provided in the middle of the sliding support B (76), which is assembled on the transverse cross tube (70) or the transverse cross push tube (83). At the middle cross hinge point of the fork push tube (83), it slides up and down along the slideway, and the sliding support B clamps the two horizontal cross tubes or one of the two horizontal cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) on the four-wheel plane of the foldable push-pull cart. Or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7); the flexible fabric (28), braided ribbon (46), and diagonal cross rope (84) are flexible materials, or are installed on the foldable push-pull cart truss in a concave pocket shape; or are fixed to the foldable push-pull cart in a ribbon weaving manner, and the ribbon weaving is either a single longitudinal or transverse weaving manner, or a cross weaving manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner; the vertical pipe belt A (7) and the vertical pipe belt B (8) are either rigid materials or flexible materials.

11. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), vertical tube (56), upper support (57), lower support (58), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19, 399), cross tube vertical tube folding device (7, 8, 27, 44, 77), four-corner pull rod folding device (27, 70, 71, 72, 73, 74, 75), handle device B (38), flexible fabric (28), universal wheel (22), also includes: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged through a rigid hinge device, and the lower longitudinal tube A is hinged. (52) is hinged to the lower longitudinal tube B (53) through a rigid hinge device. After the rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56). On the longitudinal surface of the foldable push-pull vehicle, a cross-tube vertical tube folding device (7, 8, 27, 44, 77) is installed. The cross-tube vertical tube folding device (7, 8, 27, 44, 77) includes: a vertical tube belt A (7), vertical tube with B (8), b-shaped hinge (27), horizontal tube hinge support (44), longitudinal cross tube (77), longitudinal cross tube (77) is arranged in a symmetrical projection or mirror image cross in parallel planes on both sides of the longitudinal direction, or arranged in a single oblique direction in a plane on one side of the longitudinal direction, one end of the longitudinal cross tube is directly hinged to the upper longitudinal tube A or the upper longitudinal tube B, or is hinged to it through the horizontal tube hinge support (44) or through the b-shaped hinge, and the other end is directly hinged to the lower longitudinal tube A or the lower longitudinal tube B, Or it is hinged with it through a b-shaped hinge, the longitudinal cross tubes arranged symmetrically do not need to be hinged with each other, the upper end of the vertical tube belt B is hinged with the hinge point of the upper longitudinal tube A and the upper longitudinal tube B, the lower end of the vertical tube belt B is hinged with the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, the two ends of the vertical tube belt A are hinged with the hinge point of the upper longitudinal tube A and the upper longitudinal tube B and the hinge point of the lower longitudinal tube A and the lower longitudinal tube B, and then the middle part is hinged with the middle hinge point of the two middle longitudinal tubes (54);On the transverse surfaces of both ends of the foldable push-pull cart, a four-corner pull-out rod folding device (27, 70, 71, 72, 73, 74, 75) is installed. The four-corner pull-out rod folding device includes: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a pull-out sliding support (73), a pull-out sliding sleeve (74), a pull-out sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B (71) is hinged to the connecting rod A, one end of the push-pull tube C (72) is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or directly hinged, or hinged to it through a b-shaped hinge or a horizontal tube hinge support, the other ends of the push-pull tube B (71) and the push-pull tube C (72) are hinged to the pull-out sliding support (73) on the longitudinal plane, and the pull-out sliding The sleeve (74) is installed at the upper end of the vertical tube (56), the sliding tube (75) is fixed on the sliding support (73), inserted into the sliding sleeve (74) and slides along the sliding sleeve, and the cross tubes (70) are hinged in pairs at the middle. Their lower ends are respectively hinged with the horizontal hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction, and their upper ends are respectively hinged with the sliding supports (73) on both sides of the transverse direction; the foldable push-pull cart device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), and the vertical tube (56) or directly hinged, or The foldable push-pull cart is hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of a vertical tube, or adopts a flexible fabric (28), or adopts a braided ribbon (46), or adopts a diagonally crossed rope (84), or a steel wire rope, or a wire mesh, or is configured with a flexible fabric, or also horizontally configures a braided ribbon (46) or a steel wire rope on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or configures a braided ribbon or a steel wire rope in the diagonally crossed direction when viewed from above the foldable push-pull cart; the rigid hinge device (17, 18, 19, 39) includes: a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member ( 17), an articulated support (39), each rigid articulated C, rigid articulated D, and rigid articulated member (17), are respectively fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51) and, or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), and are articulated via corresponding articulated holes (17.1, 18.1, 39.1) on the rigid articulated device, wherein the articulation with the articulated hole (17.1) is either directly articulated or articulated via the articulated support (39); the articulated support is either articulated with the articulated hole (17.1) of the rigid articulated member (17) in the shape of an oblong hole (39.1), or articulated with the articulated hole (17.1) of the rigid articulated member (17) in the shape of a circular hole;The rigid hinge device is provided with a rigid hinge clamping groove (32), and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the handle device B (38) includes: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), and the handle is installed at the upper end of the handle rod, and one side of the fixed support (68) is either hinged to the horizontal rigid hinge (78) hinge point on the horizontal horizontal cross tube A (60) and the horizontal horizontal cross tube B (61), or is hinged to the rigid hinge. The rigid support (85) on the rigid support tube A (86) and the rigid support tube B (87) is hinged at a hinge point, and the other end is hinged to the lower end of the handle rod (24.2); a slideway (69.1) is provided in the middle of the sliding support A (69), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes, and the sliding support A is hinged to the lower end of the handle rod at a hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; a slideway (76.1) is provided in the middle of the sliding support B (76), which is assembled on the transverse cross tube (70) or the transverse cross push tube (83). At the middle cross hinge point of the fork push tube (83), it slides up and down along the slideway, and the sliding support B clamps the two horizontal cross tubes or one of the two horizontal cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) on the four-wheel plane of the foldable push-pull cart. Or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7); the flexible fabric (28), braided ribbon (46), and diagonal cross rope (84) are flexible materials, or are installed on the foldable push-pull cart truss in a concave pocket shape; or are fixed to the foldable push-pull cart in a ribbon weaving manner, and the ribbon weaving is either a single longitudinal or transverse weaving manner, or a cross weaving manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner; the vertical pipe belt A (7) and the vertical pipe belt B (8) are either rigid materials or flexible materials.

12. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), middle longitudinal tube (54), locking piece (65), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19, 39), middle vertical tube side sliding folding device A (7, 8, 27, 29, 44, 64, 80), transverse composite cross folding device (60, 61, 62, 63, 64, 78, 79, 80), transverse side sliding cross folding device (44, 64, 80, 81, 82, 83), handle device B (38), flexible fabric ( 28), universal wheel (22), also includes: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, and the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device. After rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or are hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56). On the longitudinal surface of the foldable push-pull cart, a vertical tube side-drawing sliding folding device A (7, 8, 27, 29, 44, 64, 80), the middle vertical tube side pulling sliding folding device A comprises: vertical tube belt A (7), vertical tube belt B (8), push-pull tube A (64), angular side sliding sleeve (80), B-shaped hinge (27), limiter (29), horizontal tube hinge support (44), the two ends of vertical tube belt A or vertical tube belt B are respectively hinged with the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, and the hinge points of the lower longitudinal tube A and the lower longitudinal tube B, and on the longitudinal surface of the foldable push-pull vehicle, one end of the push-pull tube A (64) is hinged with the upper longitudinal tube A and the upper longitudinal tube B or the lower longitudinal tube A and the lower longitudinal tube B, or directly Hinged, or hinged to a horizontal tube hinge support (44) or hinged to it via a b-shaped hinge, the other end being hinged to an angular side sliding sleeve (80) installed on a vertical tube (56), or a two-layer vertical riser device (40), or a multi-layer vertical riser device (30), and a limiter (29) being installed in the middle of the vertical tube, or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30); on the transverse surfaces of both ends of the foldable push-pull cart, either transverse composite cross-folding devices (60, 61, 62, 63, 64, 78, 79, 80) or transverse side sliding cross-folding devices (44, 64, 80, 81, 82, 83) are installed;The transverse composite cross folding device comprises: a transverse horizontal cross tube A (60), a transverse horizontal cross tube B (61), a transverse oblique cross tube A (62), a transverse oblique cross tube B (63), a push-pull tube A (64), an angular side sliding sleeve (80), a transverse horizontal rigid hinge (78), a rigid angle hinge (79), one end of the transverse horizontal cross tube A (60) is fixed to the transverse horizontal rigid hinge (78) or other rigid hinge devices, one end of the transverse horizontal cross tube B (61) is hinged to the hinge point (78.1) of the transverse horizontal rigid hinge (78) or the hinge point on other rigid hinge devices, and the transverse horizontal cross tube A (60) is fixed to the transverse horizontal rigid hinge (78) or the hinge point on other rigid hinge devices. The other ends of the tube A (60) and the horizontal cross tube B (61) are respectively hinged to the angular side sliding sleeves (80) on the vertical tubes on both sides, and the angular side sliding sleeves (80) are hinged to the push-pull tube A (64) hinged to the upper longitudinal tube A and the upper longitudinal tube B or the lower longitudinal tube A and the lower longitudinal tube B. The middle parts of the horizontal oblique cross tube A (62) and the horizontal oblique cross tube B (63) are respectively hinged to the middle parts of the horizontal cross tube A (60) and the horizontal cross tube B (61). The upper end fixing device of the horizontal oblique cross tube A (62) has a rigid angle hinge (79), and the upper end of the horizontal oblique cross tube B (63) is hinged to the rigid angle hinge (79). The hinge point (79.1) on the angle hinge (79) is hinged, and the lower ends of the transverse oblique cross tube A (62) and the transverse oblique cross tube B (63) are respectively hinged to the transverse hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction; the transverse side sliding cross folding device includes: an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a transverse cross push tube (83), a horizontal tube hinge support (44), a push-pull tube A (64), and after one end of the transverse horizontal tube A (81) is hinged to the transverse horizontal tube B (82) through a rigid hinge device, both sides of each side are hinged to the vertical tube (56) ) The upper end is directly hinged or hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56). After the horizontal cross push tubes (83) are cross-hinged in pairs at the middle, the lower ends are respectively hinged to the angular side sliding sleeves (80) on the vertical tubes (56) on both sides. The angular side sliding sleeves (80) are hinged to the push-pull tube A (64) hinged to the upper longitudinal tube A and the upper longitudinal tube B or the lower longitudinal tube A and the lower longitudinal tube B. The upper ends of the two horizontal cross push tubes (83) are hinged to the horizontal horizontal tube A (81) and the horizontal horizontal tube B (82), either directly or via a b-shaped hinge or a horizontal tube hinge support.The foldable push-pull cart device comprises a handle device B (38), a universal wheel (22) fixed to the lower end of a vertical tube (56) via a wheel support (67), an upper longitudinal tube A (50), an upper longitudinal tube B (51), a lower longitudinal tube A (52), and a lower longitudinal tube B (53), which are directly hinged to the vertical tube (56), or hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of the vertical tube. The foldable push-pull cart is made of either a flexible fabric (28), a braided ribbon (46), a diagonally crossed rope (84), a steel rope, a wire mesh, or both flexible fabrics and a plurality of other materials. The lower longitudinal tube A (52) and the lower longitudinal tube B (53) are laterally provided with braided ribbons (46) or steel ropes, or are provided with braided ribbons or steel ropes in the diagonal cross direction when viewed from above the foldable push-pull vehicle; the rigid hinge device (17, 18, 19, 39) comprises: a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), and a hinge support (39), wherein each rigid hinge C, rigid hinge D, and rigid hinge member (17) are respectively fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), and are rigidly connected to the upper longitudinal tube A (50) and the upper longitudinal tube B (51). The corresponding hinge holes (17.1, 18.1, 39.1) on the hinge device are hinged, wherein the hinge holes (17.1) are hinged directly or hinged via a hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a round hole; a rigid hinge clamping groove (32) is provided on the rigid hinge device, and each clamped pipe section (31) falls into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; the rigid hinge device is rigid A mounting pad (15) is provided on the hinged clamping groove; the handle device B (38) comprises: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), the handle being arranged at the upper end of the handle rod, one side of the fixed support (68) being hinged to a hinge point of a horizontal rigid hinge (78) on a horizontal cross tube A (60) and a horizontal cross tube B (61), or being hinged to a hinge point of a rigid support (85) on a rigid support tube A (86) and a rigid support tube B (87), and the other end being hinged to the lower end of the handle rod (24.2);The middle part of the sliding support A (69) is provided with a slideway (69.1), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes. The sliding support A is then hinged to the lower end of the handle rod at the hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; the middle part of the sliding support B (76) is provided with a slideway (76. 1), assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), slides up and down along the slideway, the sliding support B clamps the two transverse cross tubes or one of the two transverse cross push tubes, and the sliding support B is hinged to the lower end of the handle rod at the hinge hole (76.3), and a clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod; the foldable push-pull cart is either equipped with four universal wheels (22) or equipped with Five universal wheels, or six or more universal wheels, four of which are installed at the four corners of the foldable push-pull cart, and the fifth and subsequent universal wheels are arranged symmetrically with the four universal wheels, or located in the middle of the transverse tube (20) of the four-wheel plane of the foldable push-pull cart, or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, and hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical tube belt B (8) or the vertical tube belt A (7); the flexible fabric (28), braided ribbon (46), and diagonally crossed rope (84) are flexible materials, or are installed in a concave pocket shape on the foldable push-pull cart truss; or are fixed to the foldable push-pull cart in a ribbon braiding manner, the ribbon braiding being either a single longitudinal or transverse braiding manner, or a cross-braiding manner; or are fixed to the four corners of the foldable push-pull cart in a rope diagonal cross manner; the vertical tube belt A (7) and the vertical tube belt B (8) are either rigid materials or flexible materials.

13. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), middle longitudinal tube (54), locking piece (65), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19, 39), middle vertical tube side sliding folding device B (7, 8, 27, 44, 72, 73, 74, 75), four-corner drawer rod folding device (27, 70, 71, 72, 73, 74, 75), handle device B (38), flexible fabric (28), The invention relates to a foldable push-pull wheel (22), further comprising: an eccentric hinge (35), a braided ribbon (46), and a diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, and the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device. After the rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or are hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56). On the upper surface, a middle vertical tube sliding and folding device B (7, 8, 27, 44, 72, 73, 74, 75) is installed. The middle vertical tube sliding and folding device B comprises: a vertical tube belt A (7), a vertical tube belt B (8), a b-shaped hinge (27), a horizontal tube hinge support (44), a push-pull tube B (71), a push-pull tube C (72), a sliding support (73), a sliding sleeve (74), a sliding tube (75), and the two ends of the vertical tube belt A or the vertical tube belt B are respectively connected to the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, the lower longitudinal tube The hinge point of tube A and the lower longitudinal tube B is hinged; on the longitudinal surface of the foldable push-pull cart, one end of the push-pull tube B (71) or the push-pull tube C (72) is directly hinged to the lower longitudinal tube A and the lower longitudinal tube B, or is hinged to them via a horizontal tube hinge support (44) or a b-shaped hinge, and the other end of the push-pull tube B (71) or the push-pull tube C (72) is hinged to a draw-out sliding support (73), and a draw-out sliding tube (75) is fixed on the draw-out sliding support (73), and the draw-out sliding tube (75) is inserted into a draw-out sliding sleeve (74) fixed on the vertical tube (56) and draws or slides;On the transverse surfaces of both ends of the foldable push-pull cart, a four-corner pull-out rod folding device (27, 70, 71, 72, 73, 74, 75) is installed. The four-corner pull-out rod folding device includes: a cross tube (70), a push-pull tube B (71), a push-pull tube C (72), a pull-out sliding support (73), a pull-out sliding sleeve (74), a pull-out sliding tube (75), a b-shaped hinge (27), one end of the push-pull tube B (71) is hinged to the connecting rod A, one end of the push-pull tube C (72) is hinged to the lower longitudinal tube A or the lower longitudinal tube B, or directly hinged, or hinged to it through a b-shaped hinge or a horizontal tube hinge support, the other ends of the push-pull tube B (71) and the push-pull tube C (72) are hinged to the pull-out sliding support (73) on the longitudinal plane, and the pull-out sliding The sleeve (74) is installed at the upper end of the vertical tube (56), the sliding tube (75) is fixed on the sliding support (73), inserted into the sliding sleeve (74) and slides along the sliding sleeve, and the cross tubes (70) are hinged in pairs at the middle. Their lower ends are respectively hinged with the horizontal hinges (66) fixed on the vertical tubes (56) on both sides of the transverse direction, and their upper ends are respectively hinged with the sliding supports (73) on both sides of the transverse direction; the foldable push-pull cart device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), and the vertical tube (56) or directly hinged, or The foldable push-pull cart is hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of the vertical tube, or adopts a flexible fabric (28), or adopts a braided ribbon (46), or adopts a diagonally crossed rope (84), or a steel wire rope, or a wire mesh, or is configured with a flexible fabric, or also horizontally configures a braided ribbon (46) or a steel wire rope on the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or configures a braided ribbon or a steel wire rope in the diagonally crossed direction when viewed from above the foldable push-pull cart; the rigid hinge device (17, 18, 19, 39) includes: a rigid hinge C (18), a rigid hinge D (19), a rigid hinge member (17), hinge support (39), each rigid hinge C, rigid hinge D, rigid hinge member (17), respectively fixed to upper longitudinal tube A (50) and upper longitudinal tube B (51), or to lower longitudinal tube A (52) and lower longitudinal tube B (53), and hinged via corresponding hinge holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the hinged connection with the hinge hole (17.1) is either directly hinged or hinged via the hinge support (39); the hinge support is hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of an oblong hole (39.1), or hinged to the hinge hole (17.1) of the rigid hinge member (17) in the shape of a circular hole;The rigid hinge device is provided with a rigid hinge clamping groove (32), and each clamped pipe section (31) will fall into the rigid hinge clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid hinge clamping groove of the rigid hinge device; the handle device B (38) includes: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), and the handle is installed at the upper end of the handle rod, and one side of the fixed support (68) is either hinged to the horizontal rigid hinge (78) hinge point on the horizontal horizontal cross tube A (60) and the horizontal horizontal cross tube B (61), or is hinged to the rigid hinge. The rigid support (85) on the rigid support tube A (86) and the rigid support tube B (87) is hinged at a hinge point, and the other end is hinged to the lower end of the handle rod (24.2); a slideway (69.1) is provided in the middle of the sliding support A (69), which is assembled on the middle cross hinge point of the transverse cross tube (70) or the transverse cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two transverse cross tubes or the two transverse cross push tubes, and the sliding support A is hinged to the lower end of the handle rod at a hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; a slideway (76.1) is provided in the middle of the sliding support B (76), which is assembled on the transverse cross tube (70) or the transverse cross push tube (83). At the middle cross hinge point of the fork push tube (83), it slides up and down along the slideway, and the sliding support B clamps the two horizontal cross tubes or one of the two horizontal cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit plate (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged and installed symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) on the four-wheel plane of the foldable push-pull cart. Or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical pipe belt B (8) or the vertical pipe belt A (7); the flexible fabric (28), braided ribbon (46), and diagonal cross rope (84) are flexible materials, or are installed on the foldable push-pull cart truss in a concave pocket shape; or are fixed to the foldable push-pull cart in a ribbon weaving manner, and the ribbon weaving is either a single longitudinal or transverse weaving manner, or a cross weaving manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner; the vertical pipe belt A (7) and the vertical pipe belt B (8) are either rigid materials or flexible materials.

14. Foldable push-pull cart, including: Upper longitudinal tube A (50), upper longitudinal tube B (51), lower longitudinal tube A (52), lower longitudinal tube B (53), transverse hinge (66), wheel support (67), rigid hinge device (17, 18, 19, 39), sliding hinge cross-folding device B (7, 8, 27, 44, 48, 80), transverse sliding cross-folding device (44, 80, 81, 82, 83), handle device B (38) , flexible fabric (28), universal wheel (22), also includes: eccentric hinge (35), braided ribbon (46), diagonal cross rope (84), characterized in that the upper longitudinal tube A (50) and the upper longitudinal tube B (51) are hinged via a rigid hinge device, and the lower longitudinal tube A (52) and the lower longitudinal tube B (53) are hinged via a rigid hinge device. After rigid hinge, in the horizontal arrangement state of the two vertical planes, the two sides of each are directly hinged to the two ends of the vertical tube (56), or hinged to the upper support (57) and the lower support (58) fixed on the vertical tube (56). On the longitudinal surface of the foldable push-pull cart, a side sliding hinged cross folding device B (7, 8, 27, 44, 48, 80) is installed. The side sliding hinged cross folding device B includes: vertical tube belt A (7), vertical tube belt B (8), b-shaped hinge (27), horizontal tube hinge support (44), hinged cross The pipe (48), the angle side sliding sleeve (80), one end of the hinged cross pipe (48) is hinged to the upper longitudinal pipe A and the upper longitudinal pipe B or directly, or hinged to them through the horizontal pipe hinge support (44) or through the b-shaped hinge, and the other end is hinged to the angle side sliding sleeve (80) installed on the vertical pipe (56), or the two-layer vertical riser device (40), or the multi-layer vertical riser device (30). The two hinged cross pipes on the same side are hinged to each other in the middle of the pipe (48.1), the two ends of the vertical tube belt A or the vertical tube belt B are respectively hinged to the hinge points of the upper longitudinal tube A and the upper longitudinal tube B, and the hinge points of the lower longitudinal tube A and the lower longitudinal tube B, or the vertical tube belt A or the vertical tube belt B is not installed; on the transverse surfaces of the two ends of the foldable push-pull cart, a transverse side sliding cross folding device (44, 80, 81, 82, 83) is installed, and the transverse side sliding cross folding device includes: an angular side sliding sleeve (80), a transverse horizontal tube A (81), a transverse horizontal tube B (82), a transverse cross push tube (83), a horizontal tube hinge support (44), and after one end of the transverse horizontal tube A (81) is hinged to the transverse horizontal tube B (82) through a rigid hinge device, both sides of each are hinged to the upper side of the vertical tube (56). The ends are directly hinged or hinged with the upper support (57) and the lower support (58) fixed on the vertical tube (56). After the horizontal cross push tubes (83) are cross-hinged in pairs in the middle, the lower ends are respectively hinged with the angular side sliding sleeves (80) on the vertical tubes (56) on both sides. The upper ends of the two horizontal cross push tubes (83) are hinged with the horizontal horizontal tube A (81) and the horizontal horizontal tube B (82), or directly hinged or hinged with them through a b-shaped hinge or a horizontal tube hinge support; the foldable push-pull device handle device B (38), the universal wheel (22) is fixed to the lower end of the vertical tube (56) through the wheel support (67), the upper longitudinal tube A (50), the upper longitudinal tube B (51), the lower longitudinal tube A (52), the lower longitudinal tube B (53), and the vertical tube ( 56) is directly hinged, or hinged via an eccentric hinge (35), or hinged via an upper support (57) and a lower support (58) fixed to both ends of the vertical tube, the foldable push-pull cart may be made of a flexible fabric (28), a braided ribbon (46), a diagonally crossed rope (84), a steel wire rope, or a wire mesh, or both flexible fabrics, or braided ribbons (46) or steel wire ropes are arranged transversely between the lower longitudinal tube A (52) and the lower longitudinal tube B (53), or braided ribbons or steel wire ropes are arranged in the diagonally crossed direction of the foldable push-pull cart when viewed from above; the rigid hinged device (17, 18, 19, 39) includes: a rigid hinge C (18), a rigid hinge D (1 9), a rigid hinge (17), an articulated support (39), each rigid hinge C, rigid hinge D, and rigid hinge (17) are respectively fixed to the upper longitudinal tube A (50) and the upper longitudinal tube B (51), or to the lower longitudinal tube A (52) and the lower longitudinal tube B (53), and are articulated via corresponding articulated holes (17.1, 18.1, 39.1) on the rigid hinge device, wherein the articulation with the articulated hole (17.1) is either directly articulated or articulated via the articulated support (39); the articulated support is either articulated with the articulated hole (17.1) of the rigid hinge (17) in the shape of an oblong hole (39.1), or articulated with the articulated hole (17.1) of the rigid hinge (17) in the shape of a round hole.1) Articulation; a rigid articulated clamping groove (32) is provided on the rigid articulated device, and each clamped pipe section (31) will fall into the rigid articulated clamping groove (32), and each clamped pipe section (31) is rigidly clamped; a mounting pad (15) may be provided on the rigid articulated clamping groove of the rigid articulated device; the handle device B (38) comprises: a handle (24.1), a handle rod (24.2), or a fixed support (68), or a sliding support A (69), or a sliding support B (76), and the handle is installed at the upper end of the handle rod, and one side of the fixed support (68) is hinged to the horizontal rigid hinge (78) hinge point on the horizontal horizontal cross tube A (60) and the horizontal horizontal cross tube B (61). Or it is hinged to the rigid support (85) hinge point on the rigid support tube A (86) and the rigid support tube B (87), and the other end is hinged to the lower end of the handle rod (24.2); the middle part of the sliding support A (69) is provided with a slideway (69.1), which is assembled on the middle cross hinge point of the cross tube (70) or the cross push tube (83), and slides up and down along the slideway. The sliding support A completely clamps the two cross tubes or the two cross push tubes, and the sliding support A is hinged to the lower end of the handle rod at the hinge hole (69.3). A clamping spring (69.2) is provided above the hinge hole where the sliding support A is hinged to the handle rod; the middle part of the sliding support B (76) is provided with a slideway (76.1), which is assembled on the cross tube (70) or At the middle cross hinge point of the transverse cross push tube (83), it slides up and down along the slideway, and the sliding support B clamps the two transverse cross tubes or one of the two transverse cross push tubes. The sliding support B is then hinged to the lower end of the handle rod at the hinge hole (76.3). A clamping spring (76.2) and a limit piece (76.4) are provided above the hinge hole where the sliding support B is hinged to the handle rod. The foldable push-pull cart is equipped with four universal wheels (22), five universal wheels, or six or more universal wheels. The four universal wheels are installed at the four corners of the foldable push-pull cart, and the fifth and more universal wheels are arranged symmetrically with the four universal wheels, or are located in the middle of the transverse tube (20) on the four-wheel plane of the foldable push-pull cart. , or located on the two longitudinal sides of the four-wheel plane of the foldable push-pull cart, hinged to the rigid hinge point on the longitudinal rigid hinge device or directly fixed to the lower end of the vertical tube belt B (8) or the vertical tube belt A (7); the flexible fabric (28), braided ribbon (46), and diagonal cross rope (84) are flexible materials, or are installed on the foldable push-pull cart truss in a concave pocket shape; or are fixed to the foldable push-pull cart in a ribbon weaving manner, and the ribbon weaving is either a single longitudinal or transverse weaving manner, or a cross weaving manner; or are fixed to the four corners of the foldable push-pull cart in a diagonal cross rope manner; the vertical tube belt A (7) and the vertical tube belt B (8) are either rigid materials or flexible materials.

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