Folding trolley

Abstract

The utility model relates to a folding trolley which realizes folding and unfolding of a trolley frame by utilizing foldable side connecting rod assemblies, a front connecting rod assembly, a rear connecting rod assembly and a folding chassis. The overall length of the telescopic supporting rod is changed through an outer pipe and an inner column which are connected in a sliding mode, and the telescopic supporting rod is associated with at least one of the side connecting rod assemblies, the front connecting rod assembly and the rear connecting rod assembly through a bottom connecting part, so that the frame has the first state that when the corresponding connecting rod assemblies are unfolded, the bottom connecting part drives the inner column to ascend under the action of corresponding connecting rods; in the second state, when the corresponding connecting rod assemblies are folded, the bottom connecting parts drive the inner columns to descend under the action of the corresponding connecting rods, the folding trolley integrates the large inner space in the unfolded state and the small storage space in the folded state, the structure is simple, and user operation is convenient.

Description

Technical Field

[0001] The utility model relates to the technical field of trolleys, in particular to a foldable trolley. Background Art

[0002] As people's living standards improve, their desire for outdoor activities becomes stronger and stronger, and their requirements for convenience in life become higher and higher. When engaging in outdoor activities, they need to carry some miscellaneous items required for the activities. At this time, foldable carts that are easy to fold and carry come into being.

[0003] A Chinese utility model patent with announcement number CN201712643U discloses a luggage trolley with bundles, including a foldable frame structure formed by connecting rods, the frame has four vertical legs, the vertical legs are telescopic rod structures, and the two sides of the frame each have two sets of four-bar linkage mechanisms that are mutually hinged, the upper ends of the vertical legs are fixed with upper brackets, the lower ends of the vertical legs are fixed with lower brackets, the upper brackets are fixed to the upper ends of the inner tubes of the vertical legs, the lower brackets are fixed to the lower ends of the outer tubes of the vertical legs, the inner tubes are inserted into the outer tubes, and the connecting rods are respectively connected to the upper and lower ends of the vertical legs. When the frame is unfolded, the two ends of the four-bar linkage mechanism are close to each other on the vertical legs, driving the inner tubes to be inserted into the outer tubes, and the internal space of the frame is relatively large.

[0004] However, this structure also brings some problems: when the frame is folded, the two ends of the four-bar linkage move away from each other on the vertical support leg, driving the inner tube to extend out of the outer tube, resulting in the frame height in the folded state being higher than the frame height in the unfolded state, making the storage space required for the folded frame larger; and if the inner tube in the vertical support leg is removed and the two ends of the four-bar linkage are directly connected to the two ends of the outer tube, the length of the rod in the four-bar linkage needs to be shortened, which leads to a smaller internal space of the frame in the unfolded state. Therefore, the folding stroller in the above patent cannot take into account both the large internal space in the unfolded state and the small storage space in the folded state.

[0005] Therefore, a new folding trolley needs to be designed. Utility Model Content

[0006] The technical problem to be solved by the utility model is to overcome the problem that the folding cart in the prior art cannot have a large internal space in the unfolded state and a small storage space in the folded state, thereby providing a folding cart.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] A foldable handcart comprises a frame, wheels and a traction part, wherein the wheels are located at the bottom of the frame, and the frame comprises

[0009] The retractable support rod is located at the four corners of the frame, and its bottom is connected to the wheels at the corresponding positions.

[0010] A foldable side link assembly is located on the side of the frame and is respectively connected to the two telescopic support rods;

[0011] A foldable front link assembly, located at the front side of the frame and connected to the two telescopic support rods respectively;

[0012] A foldable rear connecting rod assembly is located at the rear side of the frame and is respectively connected to the two telescopic support rods;

[0013] A folding chassis, located at the bottom of the frame, connected to the retractable support rods at four corners;

[0014] The telescopic support rod comprises an outer tube, an inner column, a top connection part and a bottom connection part, the inner column is slidably connected to the outer tube, the top connection part is fixedly connected to the top end of the outer tube, the bottom connection part is slidably sleeved on the outer tube, and a vertical notch is provided on the outer tube, and the bottom connection part is connected to the inner column through the vertical notch;

[0015] The link ends of at least one of the side link assembly, the front link assembly and the rear link assembly are respectively hinged to the top connection part and the bottom connection part, so that the frame has

[0016] When the corresponding connecting rod assembly is unfolded, the bottom connecting part drives the inner column to rise under the action of the corresponding connecting rod; and

[0017] When the corresponding connecting rod assembly is retracted, the bottom connecting part drives the inner column to descend to the second state under the action of the corresponding connecting rod.

[0018] Preferably, the bottom connecting part comprises a first body and a connecting piece for connecting with the inner column, and the first body has a through hole so that the bottom connecting part can be slidably sleeved on the outer tube;

[0019] The first body has a first connecting hole, and the connecting piece passes through the first connecting hole and the vertical slot to be fixedly connected with the second connecting hole on the inner column; when the bottom connecting part moves along the outer tube, the connecting piece moves in the vertical slot.

[0020] Preferably, the bottom connecting portion further comprises two first connecting frames forming a set angle, and the first connecting frames are connected to the first body;

[0021] The first connecting frame is used for being hingedly connected with the connecting rod in the side connecting rod assembly, the front connecting rod assembly or the rear connecting rod assembly.

[0022] Preferably, the side link assembly comprises a first side link hinged to the top connection portion and a second side link hinged to the bottom connection portion; and / or

[0023] The front link assembly includes a first front link hinged to the top connection portion and a second front link hinged to the bottom connection portion.

[0024] Preferably, the side link assembly, the front link assembly, and the rear link assembly all include a plurality of cross-connected links, and the number of links in the side link assembly is greater than the number of links in the front link assembly and greater than the number of links in the rear link assembly;

[0025] The heights of the side link assembly, the front link assembly and the rear link assembly after the frame is folded are not greater than the height of the telescopic support rod.

[0026] Preferably, the rear link assembly includes a first rear link hinged to the top connecting portion and a second rear link hinged to the bottom connecting portion.

[0027] Preferably, the rear connecting rod assembly further comprises rear upright rods located on both sides of the cross-connected connecting rods, the ends of the connecting rods are hinged to the rear upright rods, the upper parts of the rear upright rods are detachably connected to the top connecting parts on the two telescopic support rods, and the lower parts of the rear upright rods are hinged to the bottom parts on the two telescopic support rods.

[0028] The top connecting portion includes a hinge groove for hinge connection of the side link assembly and a clamping groove clamped with the upper part of the rear upright rod;

[0029] When the vehicle frame is unfolded, the upper portion of the rear connecting rod assembly can be separated from the telescopic support rod, so that the rear connecting rod assembly is flipped downward relative to the telescopic support rod.

[0030] Preferably, the rear connecting rod assembly includes two connecting ropes, one end of which is connected to the rear pillar, and the other end of which is connected to the telescopic support rod.

[0031] Preferably, the foldable chassis comprises at least two groups of X-shaped connecting rod groups, and adjacent X-shaped connecting rod groups are hinged to each other and to the bottom of the retractable support rod at the corresponding position.

[0032] Preferably, a hinge and a connecting rod are provided at the connection of the two groups of X-shaped connecting rod assemblies, one end of the connecting rod is connected to the hinge, and the other end is slidably connected to the lower hinge of the connecting rod of the side connecting rod assembly;

[0033] The connecting rod is provided with a vertical slide groove, and the connecting shaft at the lower hinge passes through the slide groove. When the frame is unfolded, the connecting shaft is located at the top of the slide groove; when the frame is folded, the connecting shaft is located at the bottom of the slide groove.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] The foldable handcart provided in the above technical solution utilizes foldable side link assemblies, front link assemblies, rear link assemblies and a foldable chassis to realize the folding and unfolding of the frame; the telescopic support rod realizes the overall length change through the outer tube and the inner column connected by sliding, and is associated with at least one of the side link assemblies, the front link assemblies and the rear link assemblies through the bottom connecting part, and the ends of these foldable link assemblies will move away from or approach each other when folded or unfolded. Therefore, when the frame is unfolded, the side link assemblies, the front link assemblies and the rear link assemblies will also be unfolded accordingly, and the bottom connecting part drives the inner column to rise under the action of the corresponding link, and the frame is unfolded. When the frame is opened to the maximum, the inner column also rises to the highest point, and the overall height of the telescopic support rod is the maximum. At this time, the internal space of the frame is larger than the internal space without the inner column; and when the frame is folded and retracted, the side link assembly, the front link assembly and the rear link assembly will also be retracted accordingly, and the bottom connecting part drives the inner column to descend under the action of the corresponding link. When the frame is retracted to the minimum, the inner column is also basically completely retracted into the outer tube, and the overall height of the telescopic support rod is the shortest. When the folding widths of the side link assembly, the front link assembly and the rear link assembly are consistent, the folding height of the frame is minimized, thereby, the storage space required for the frame in the folded state is small. The folding trolley of the utility model takes into account the large internal space in the unfolded state and the small storage space in the folded state, and has a simple structure and is convenient for users to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 This is a schematic diagram of the structure of the trolley in the folded state according to the first embodiment of the utility model;

[0038] Figure 2 This is a structural schematic diagram of the trolley in the unfolded state according to the first embodiment of the utility model;

[0039] Figure 3 for Figure 2 A schematic diagram of the enlarged structure at A in the middle;

[0040] Figure 4 for Figure 2 A schematic diagram of the enlarged structure at B in the middle;

[0041] Figure 5 This is a schematic diagram of the folding process of the trolley in Embodiment 1 of the utility model;

[0042] Figure 6 This is a structural schematic diagram of a trolley according to Embodiment 2 of the present utility model;

[0043] Figure 7 for Figure 6 Schematic diagram of the enlarged structure at point C in the middle.

[0044] Description of reference numerals:

[0045] 10. Frame; 11. Accommodation space;

[0046] 20. telescopic support rod; 21. outer tube; 211. vertical notch; 22. inner column; 23. bottom connection part; 231. first body; 232. connection piece; 233. first connection frame; 234. through hole; 235. first connection hole; 24. top connection part; 241. second body; 242. through hole; 243. second connection frame; 244. hinge slot; 245. slot;

[0047] 30. Side connecting rod assembly; 31. First side connecting rod; 32. Second side connecting rod; 33. Connecting shaft;

[0048] 40. front link assembly; 41. first front link; 42. second front link;

[0049] 50. rear connecting rod assembly; 51. first rear connecting rod; 52. second rear connecting rod; 53. rear upright rod; 54. connecting rope;

[0050] 60, folding chassis; 61, X-type connecting rod group; 611, central connecting part; 612, outer connecting rod; 62, hinge; 63, connecting rod; 631, slide groove;

[0051] 70, wheel; 71, front wheel; 72, rear wheel; 73, first mounting seat; 74, second mounting seat;

[0052] 80. traction part; 81. handle; 82. handle bar; 83. handle connecting rod; 84. connecting seat. DETAILED DESCRIPTION

[0053] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0054] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] As attached Figure 1 To Attachment Figure 7 As shown, an embodiment of the utility model provides a folding trolley, including a frame 10, wheels 70 and a traction part 80. The wheels 70 are located at the bottom of the frame 10 for convenient movement of the folding trolley. The wheels 70 can be fixed wheels or universal wheels, wide wheels or narrow wheels, with brakes or without brakes.

[0057] The frame 10 is a foldable frame 10 , which can be unfolded to form a storage space 11 for storing items inside, and can also be folded to reduce the floor space and facilitate storage. Specifically, the vehicle frame 10 includes a telescopic support rod 20, a foldable side link assembly 30, a front link assembly 40, a rear link assembly 50 and a foldable chassis 60. The telescopic support rod 20 is located at the four corners of the vehicle frame 10, and its bottom is connected to the wheels 70 at the corresponding position, serving as a pillar connecting the various surfaces of the vehicle frame 10; the side link assembly 30 is located on the side of the vehicle frame 10, and is respectively connected to two telescopic support rods 20, that is, the number of the side link assembly 30 is two groups, which are respectively located on the two side surfaces of the vehicle frame 10 and are connected to the two telescopic support rods 20 on the corresponding side. When the side link assembly 30 is folded, the two telescopic support rods 20 on the corresponding side are close to each other along the folding direction. When the side link assembly 30 is unfolded, the two telescopic support rods 20 on the corresponding side are away from each other along the unfolding direction. The side link assembly 30 serves as a side support of the accommodating space 11. Support; similarly, the front link assembly 40 is located at the front side of the frame 10, and is respectively connected to the two telescopic support rods 20. When the front link assembly 40 is folded, the two telescopic support rods 20 located at the front side of the frame 10 move closer to each other along the folding direction. When the front link assembly 40 is unfolded, the two telescopic support rods 20 located at the front side of the frame 10 move away from each other along the unfolding direction. The front link assembly 40 serves as a front support for the accommodating space 11; the rear link assembly 50 is located at the rear side of the frame 10, and is respectively connected to the two telescopic support rods 20. When the rear link assembly 50 is folded, the two telescopic support rods 20 located at the rear side of the frame 10 move closer to each other along the folding direction. When the rear link assembly 50 is unfolded, the two telescopic support rods 20 located at the rear side of the frame 10 move away from each other along the unfolding direction. The rear link assembly 50 serves as a rear support for the accommodating space 11. The foldable chassis 60 is located at the bottom of the frame 10 and is respectively connected to the retractable support rods 20 at the four corners. When the frame 10 is unfolded, the foldable chassis 60 is also unfolded to serve as the bottom support of the accommodating space 11. When the frame 10 is folded and folded, the foldable chassis 60 is also folded and folded.

[0058] In order to expand the storage space 11 when the frame 10 is unfolded, on the one hand, the width of the side link assembly 30, the front link assembly 40, and the rear link assembly 50 when they are unfolded can be increased, that is, the length and width of the storage space 11 can be increased. This means that an increase in the number of links or the length of a single link will lead to a significant increase in the weight of the frame 10, and will also cause the storage volume of the frame 10 to increase when it is folded; on the other hand, the height of the support rod can be increased, that is, the height of the storage space 11 can be increased. Similarly, simply increasing the height of the support rod will also cause the storage volume of the frame 10 to increase when it is folded.

[0059] In order to solve the above problems, in this embodiment, the telescopic support rod 20 includes an outer tube 21, an inner column 22, a top connecting portion 24 and a bottom connecting portion 23. The inner column 22 is slidably connected to the outer tube 21, the top connecting portion 24 is fixedly connected to the top end of the outer tube 21, and the bottom connecting portion 23 is slidably sleeved on the outer tube 21, and a vertical slot 211 is provided on the outer tube 21. The bottom connecting portion 23 is connected to the inner column 22 through the vertical slot 211, and the connecting rod ends of at least one of the side link assembly 30, the front link assembly 40 and the rear link assembly 50 are respectively hinged to the top connecting portion 24 and the bottom connecting portion 23, so that the frame 10 has a first state in which the bottom connecting portion 23 drives the inner column 22 to rise under the action of the corresponding link when the corresponding link assembly is unfolded; and a second state in which the bottom connecting portion 23 drives the inner column 22 to descend under the action of the corresponding link when the corresponding link assembly is folded. The telescopic support rod 20 achieves overall length change through the outer tube 21 and the inner column 22 that are slidably connected, and is associated with at least one of the side link assembly 30, the front link assembly 40 and the rear link assembly 50 through the bottom connection part 23. When these foldable link assemblies are folded or unfolded, the ends will move away from or approach each other. Therefore, when the frame 10 is unfolded, the side link assembly 30, the front link assembly 40 and the rear link assembly 50 will also be unfolded accordingly. The bottom connection part 23 drives the inner column 22 to rise under the action of the corresponding link. When the frame 10 is unfolded to the maximum, the inner column 22 also rises to the highest point, and the overall height of the telescopic support rod 20 is the maximum. When the frame 10 is folded and retracted, the side link assembly 30, the front link assembly 40 and the rear link assembly 50 will also be retracted accordingly, and the bottom connecting part 23 drives the inner column 22 to descend under the action of the corresponding link. When the frame 10 is retracted to the minimum, the inner column 22 is also basically retracted into the outer tube 21, and the overall height of the telescopic support rod 20 is the shortest. When the folding widths of the side link assembly 30, the front link assembly 40 and the rear link assembly 50 are consistent, the folding height of the frame 10 is minimized, and thus, the storage space required for the frame 10 in the folded state is small. The folding trolley of the utility model takes into account the large internal space in the unfolded state and the small storage space in the folded state, and has a simple structure and is convenient for users to operate.

[0060] When controlling the lifting and lowering of the inner column 22 relative to the outer tube 21, a force can be directly applied to the bottom connection part 23 on the telescopic support rod 20 to make it drive the inner column 22 to lift or lower. A force can also be directly applied to the inner column 22 to make it drive the bottom connection part 23 to lift or lower. The bottom connection part 23 can be driven to move on the outer tube 21 by unfolding or folding at least one of the side link assembly 30, the front link assembly 40 and the rear link assembly 50 connected to the bottom connection part 23, thereby driving the inner column 22 to lift or lower.

[0061] As attached Figure 1 To Attachment Figure 5In the first embodiment shown, for the bottom connection part 23 on the telescopic support rod 20 connected to the front wheel 71, the connecting rod end of the side connecting rod assembly 30 on one side and the connecting rod end of the front connecting rod assembly 40 on the same side are simultaneously connected to the bottom connection part 23 on the corresponding side, so that when the corresponding connecting rod assembly is deployed, the bottom connection part 23 drives the inner column 22 to rise under the action of the corresponding connecting rod, and when the corresponding connecting rod assembly is retracted, the bottom connection part 23 drives the inner column 22 to fall under the action of the corresponding connecting rod, which is more convenient and labor-saving to operate. For the bottom connection part 23 on the telescopic support rod 20 connected to the rear wheel 72, the connecting rod end of the side connecting rod assembly 30 on one side and the connecting rod end of the rear connecting rod assembly 50 on the same side are simultaneously connected to the bottom connection part 23 on the corresponding side, so that when the corresponding connecting rod assembly is deployed, the bottom connection part 23 drives the inner column 22 to rise under the action of the corresponding connecting rod, and when the corresponding connecting rod assembly is retracted, the bottom connection part 23 drives the inner column 22 to fall under the action of the corresponding connecting rod, which is more convenient and labor-saving to operate.

[0062] In this embodiment, the structures of the top connecting parts 24 on each telescopic support rod 20 are substantially the same, and the structures of the bottom connecting parts 23 on each telescopic support rod 20 are also substantially the same.

[0063] Specifically, as attached Figure 3 As shown, the bottom connection part 23 includes a first body 231, a connection piece 232 for connecting with the inner column 22, and a first connection frame 233 forming a set angle. The first body 231 has a through hole 234, so that the bottom connection part 23 is slidably sleeved on the outer tube 21; the first body 231 has a first connection hole 235, and the connection piece 232 passes through the first connection hole 235 and the vertical slot 211 and is fixedly connected with the second connection hole on the inner column 22; when the bottom connection part 23 moves along the outer tube 21, the connection piece 232 moves in the vertical slot 211, thereby driving the inner column 22 to rise and fall in the outer tube 21. The connection piece 232 can be a fixing screw, and at least one of the first connection hole 235 and the second connection hole can be a screw hole.

[0064] As attached Figure 4As shown, the first connecting frame 233 is connected to the first body 231; generally, the set angle between the two first connecting frames 233 is 90°. It should be noted that due to processing errors, the set angle can be a range value, floating within the allowable error of 90°. The first connecting frame 233 is used to be hinged with the connecting rod in the side connecting rod assembly 30, the front connecting rod assembly 40 or the rear connecting rod assembly 50. For example, for the bottom connecting portion 23 on the telescopic support rod 20 connected to the front wheel 71, the side connecting rod assembly 30 includes a first side connecting rod 31 hinged to the top connecting portion 24 and a second side connecting rod 32 hinged to the bottom connecting portion 23; the front connecting rod assembly 40 includes a first front connecting rod 41 hinged to the top connecting portion 24 and a second front connecting rod 42 hinged to the bottom connecting portion 23. One of the first connecting frames 233 on a bottom connecting portion 23 is hinged to a second side connecting rod 32, and the other is hinged to a second side connecting rod 32. A first connecting frame 233 is hinged to a second front connecting rod 42; for the bottom connecting portion 23 on the telescopic support rod 20 connected to the rear wheel 72, the side connecting rod assembly 30 includes a first side connecting rod 31 hinged to the top connecting portion 24 and a second side connecting rod 32 hinged to the bottom connecting portion 23; the rear connecting rod assembly 50 includes a first rear connecting rod 51 hinged to the top connecting portion 24 and a second rear connecting rod 52 hinged to the bottom connecting portion 23, one of the first connecting frames 233 on a bottom connecting portion 23 is hinged to a second side connecting rod 32, and the other first connecting frame 233 is hinged to a second rear connecting rod 52.

[0065] As attached Figure 3 and attached Figure 4As shown, the top connecting portion 24 includes a second body 241 and a second connecting frame 243 forming a set angle. The second body 241 is fixedly connected to the top end of the outer tube 21 by screws, and has a through hole 242 for the inner column 22 to pass through. The second connecting frame 243 is connected to the second body 241, and its set angle is basically the same as the set angle between the first connecting frame 233 of the bottom connecting portion 23 on the same telescopic support rod 20. The second connecting frame 243 is used to be hinged with the connecting rod in the side connecting rod assembly 30, the front connecting rod assembly 40 or the rear connecting rod assembly 50. For example, for the top connecting portion 24 on the telescopic support rod 20 connected to the front wheel 71, the side connecting rod assembly 30 includes a first side connecting rod 31 hinged with the top connecting rod 24 and a second side connecting rod 32 hinged with the top connecting rod 24; the front connecting rod assembly 40 includes a first front connecting rod 41 hinged with the top connecting rod 24 and a second front connecting rod 42 hinged with the top connecting rod 24. One of the second connecting frames 243 on a top connecting portion 24 is hinged with one first side connecting rod 31, and the other is hinged with the other side connecting rod 31. A second connecting frame 243 is hinged to a first front link 41; for the top connecting portion 24 on the telescopic support rod 20 connected to the rear wheel 72, the side link assembly 30 includes a first side link 31 hinged to the top connecting portion 24 and a second side link 32 hinged to the top connecting portion 24; the rear link assembly 50 includes a first rear link 51 hinged to the top connecting portion 24 and a second rear link 52 hinged to the top connecting portion 24, one of the second connecting frames 243 on a top connecting portion 24 is hinged to a first side link 31, and the other second connecting frame 243 is hinged to a first rear link 51.

[0066] As attached Figure 2 and attached Figure 5As shown, the side link assembly 30, the front link assembly 40, and the rear link assembly 50 all include a plurality of cross-connected links, and the number of links in the side link assembly 30 is greater than the number of links in the front link assembly 40 and greater than the number of links in the rear link assembly 50; for example, the number of links in the side link assembly 30 is 8, including the first side link 31 and the second side link 32 mentioned above; the number of links in the front link assembly 40 is 4, including the first front link 41 and the second front link 42 mentioned above; the number of links in the rear link assembly 50 is 4, including the first rear link 51 and the second rear link 52 mentioned above. The purpose of such arrangement is that the traction member is generally arranged on the front side of the frame 10, and the front and rear sides of the frame 10 are narrower than the left and right sides, which makes it more convenient for users to push and pull the folding cart. Moreover, a larger number of links also makes the length of the side-link assembly 30 longer after unfolding, and the accommodating space 11 of the frame 10 is larger. At the same time, the heights of the side-link assembly 30, the front-link assembly 40 and the rear-link assembly 50 after the frame 10 is folded are not greater than the height of the telescopic support rod 20, thereby ensuring the height of the frame 10 after folding. By reasonably arranging the link distribution of the side-link assembly 30, the width of the side-link assembly 30 after folding can also be made smaller, thereby making the storage volume of the frame 10 smaller.

[0067] As attached Figure 2 and attached Figure 5 As shown, in this embodiment, the traction part 80 includes a handle 81, a handle rod 82 and a handle connecting rod 83. The handle 81 is arranged at the top of the handle rod 82. The handle rod 82 can be a telescopic structure. When the frame 10 is in the unfolded state, the overall length of the handle rod 82 can be lengthened to facilitate pushing and pulling the folding trolley. When the frame 10 is in the folded state, the overall length of the handle rod 82 can be shortened to further reduce the folding volume. The bottom of the handle rod 82 is hinged to the top of the two wheels 70 as the front wheels 71 through the handle connecting rod 83. Specifically, the top of the front wheel 71 is fixed with a first mounting seat 73. The number of the handle connecting rod 83 is two, one end of which is hinged to the first mounting seat 73, and the other end is hinged to the connecting seat 84 at the bottom of the handle rod 82. When the frame 10 is folded and folded, the connecting seat 84 moves downward, driving part of the handle connecting rod 83 to be placed between the two front wheels 71. The first mounting seats 73 on both sides are located on both sides of the handle rod 82 as the front wheels 71 approach each other.

[0068] As attached Figure 2 and attached Figure 5As shown, in this embodiment, the folding chassis 60 includes at least two groups of X-shaped link groups 61, and adjacent X-shaped link groups 61 are hinged to each other and to the bottom of the retractable support rod 20 at the corresponding position, that is, the two ends of one group of X-shaped link groups 61 are respectively hinged to the first mounting seat 73 located at the top of the front wheel 71 and the bottom of the retractable support rod 20, and the two ends of the other group of X-shaped link groups 61 are respectively hinged to the second mounting seat 74 located at the top of the rear wheel 72 and the bottom of the retractable support rod 20.

[0069] As attached Figure 5 As shown, the X-shaped connecting rod group 61 includes a central connecting part 611 located in the center and outer connecting rods 612 respectively hinged to the central connecting part 611, and the connection between the outer connecting rods 612 of adjacent X-shaped connecting rod groups 61 is provided with a hinge 62 and a connecting rod 63, one end of the connecting rod 63 is connected to the hinge 62, and the other end is slidably connected to the lower hinge of the connecting rod of the side connecting rod assembly 30; specifically, a vertical slide groove 631 is provided on the connecting rod 63, and the connecting shaft 33 at the lower hinge passes through the slide groove 631. When the frame 10 is unfolded, the connecting shaft 33 is located at the top of the slide groove 631; when the frame 10 is folded, the connecting shaft 33 is located at the bottom of the slide groove 631. The function of the connecting rod 63 is to strengthen the connection between the middle part of the folding chassis 60 and the side link assembly 30 when the frame 10 is unfolded. The force applied to the middle part of the folding chassis 60 can be transmitted to the side link assembly 30 through the connecting rod 63, and then transmitted to the telescopic support rod 20, thereby improving the supporting force of the folding chassis 60 for the items in the accommodating space 11, making the folding chassis 60 more stable, thereby improving the overall stability of the frame 10.

[0070] As attached Figure 6 and attached Figure 7 The second embodiment shown is different from the first embodiment in that the rear connecting rod assembly 50 can be opened relative to the frame 10 to expand the accommodating space 11 of the frame 10. Therefore, in this embodiment, the top connecting portion 24 and the bottom connecting portion 23 on the telescopic support rod 20 connected to the front wheel 71 can have the same structure as that in the first embodiment; at the same time, since the rear connecting rod assembly 50 can be opened, it is detachably connected to the top connecting portion 24 and is hinged to the bottom of the telescopic support rod 20, and the top connecting portion 24 and the bottom connecting portion 23 on the telescopic support rod 20 connected to the rear wheel 72 are different.

[0071] Specifically, as attached Figure 6 As shown, for the bottom connecting portion 23 on the telescopic support rod 20 connected to the rear wheel 72, its structure can be the same as that of the first embodiment, but the first connecting frame 233 on the bottom connecting portion 23 is only hinged to the second side link 32 in the side link assembly 30, and is not connected to the rear link assembly 50.

[0072] As attached Figure 6 and attached Figure 7As shown, the rear connecting rod assembly 50 also includes rear upright rods 53 located on both sides of the cross-connected connecting rods, the ends of the connecting rods are hinged to the rear upright rods 53, the upper parts of the rear upright rods 53 are detachably connected to the top connecting parts 24 on the two telescopic support rods 20, and the lower parts of the rear upright rods 53 are hinged to the bottom parts on the two telescopic support rods 20.

[0073] The top connection portion 24 on the telescopic support rod 20 connected to the rear wheel 72 includes a hinge groove 244 for hinged connection of the side link assembly 30 and a clamping groove 245 clamped with the upper part of the rear upright 53. The hinge groove 244 is hinged to the first side link 31 of the side link assembly 30. When the frame 10 is unfolded, the upper part of the rear link assembly 50 can be separated from the telescopic support rod 20, so that the rear link assembly 50 flips downward relative to the telescopic support rod 20.

[0074] In order to prevent the rear link assembly 50 from tipping over too much and colliding with the ground, the rear link assembly 50 includes two connecting ropes 54, one end of the connecting rope 54 is connected to the rear column, and the other end is connected to the telescopic support rod 20, so that the rear link assembly 50 can basically maintain a horizontal or other set angle.

[0075] The frame 10 of the folding trolley of the embodiment of the utility model can be provided with an inner lining adapted to the accommodation space 11, and the inner lining can be detachably fixed to the top of the inner column 22; when the rear connecting rod assembly 50 of the frame 10 can be turned down, the corresponding position of the inner lining can also be turned down along with the rear connecting rod assembly 50. Of course, in some cases, the inner lining may not be provided, and the frame 10 can be directly used to accommodate items. The structure of the inner lining is various, and the inner lining structure in the prior art can be adopted, which will not be repeated here.

[0076] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A folding trolley, comprising a frame, wheels and a traction part, wherein the wheels are located at the bottom of the frame, characterized in that: The frame includes The retractable support rod is located at the four corners of the frame, and its bottom is connected to the wheels at the corresponding positions. A foldable side link assembly is located on the side of the frame and is respectively connected to the two telescopic support rods; A foldable front link assembly, located at the front side of the frame and connected to the two telescopic support rods respectively; A foldable rear connecting rod assembly is located at the rear side of the frame and is respectively connected to the two telescopic support rods; A folding chassis, located at the bottom of the frame, connected to the retractable support rods at four corners; The telescopic support rod comprises an outer tube, an inner column, a top connection part and a bottom connection part, the inner column is slidably connected to the outer tube, the top connection part is fixedly connected to the top end of the outer tube, the bottom connection part is slidably sleeved on the outer tube, and a vertical notch is provided on the outer tube, and the bottom connection part is connected to the inner column through the vertical notch; The link ends of at least one of the side link assembly, the front link assembly and the rear link assembly are respectively hinged to the top connection part and the bottom connection part, so that the frame has A first state in which the bottom connecting portion drives the inner column to rise under the action of the corresponding connecting rod when the corresponding connecting rod assembly is unfolded; and When the corresponding connecting rod assembly is retracted, the bottom connecting part drives the inner column to descend to the second state under the action of the corresponding connecting rod.

2. The foldable trolley according to claim 1, characterized in that: The bottom connecting part comprises a first body and a connecting piece for connecting with the inner column, the first body has a through hole so that the bottom connecting part can be slidably sleeved on the outer tube; The first body has a first connecting hole, and the connecting piece passes through the first connecting hole and the vertical slot to be fixedly connected with the second connecting hole on the inner column; when the bottom connecting part moves along the outer tube, the connecting piece moves in the vertical slot.

3. The foldable trolley according to claim 2, characterized in that: The bottom connecting portion further comprises two first connecting frames forming a set angle, wherein the first connecting frames are connected to the first body; The first connecting frame is used for being hingedly connected with the connecting rod in the side connecting rod assembly, the front connecting rod assembly or the rear connecting rod assembly.

4. The foldable trolley according to claim 1, 2 or 3, characterized in that: The side link assembly comprises a first side link hinged to the top connection portion and a second side link hinged to the bottom connection portion; and / or The front link assembly includes a first front link hinged to the top connection portion and a second front link hinged to the bottom connection portion.

5. The foldable trolley according to claim 1, 2 or 3, characterized in that: The side link assembly, the front link assembly, and the rear link assembly all include a plurality of cross-connected links, and the number of links in the side link assembly is greater than the number of links in the front link assembly and greater than the number of links in the rear link assembly; The heights of the side link assembly, the front link assembly and the rear link assembly after the frame is folded are not greater than the height of the telescopic support rod.

6. The foldable trolley according to claim 4, characterized in that: The rear link assembly includes a first rear link hinged to the top connection portion and a second rear link hinged to the bottom connection portion.

7. The foldable trolley according to claim 4, characterized in that: The rear connecting rod assembly also includes rear upright rods located on both sides of the cross-connected connecting rods, the ends of the connecting rods are hinged to the rear upright rods, the upper parts of the rear upright rods are detachably connected to the top connecting parts on the two telescopic support rods, and the lower parts of the rear upright rods are hinged to the bottom parts on the two telescopic support rods. The top connecting portion includes a hinge groove for hinge connection of the side link assembly and a clamping groove clamped with the upper part of the rear upright pole; When the vehicle frame is unfolded, the upper portion of the rear connecting rod assembly can be separated from the telescopic support rod, so that the rear connecting rod assembly is flipped downward relative to the telescopic support rod.

8. The foldable trolley according to claim 7, characterized in that: The rear connecting rod assembly comprises two connecting ropes, one end of which is connected to the rear upright rod, and the other end of which is connected to the telescopic supporting rod.

9. The foldable trolley according to claim 4, characterized in that: The folding chassis comprises at least two groups of X-shaped connecting rod groups, and the adjacent X-shaped connecting rod groups are hinged to each other and hinged to the bottom of the telescopic support rod at the corresponding position.

10. The foldable trolley according to claim 9, characterized in that: A hinge and a connecting rod are provided at the connection of the two groups of X-shaped connecting rod assemblies, one end of the connecting rod is connected to the hinge, and the other end is slidably connected to the lower hinge of the connecting rod of the side connecting rod assembly; The connecting rod is provided with a vertical slide groove, and the connecting shaft at the lower hinge passes through the slide groove. When the frame is unfolded, the connecting shaft is located at the top of the slide groove; when the frame is folded, the connecting shaft is located at the bottom of the slide groove.

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