A folding handcart

Abstract

A foldable handcart is characterized by comprising a handle assembly, a foldable frame, casters, and a storage pocket. The frame includes four vertical poles arranged in front, back, left, and right directions and a wheel frame assembly. The vertical poles are arranged above the wheel frame assembly, wherein two vertical poles on the front side and two vertical poles on the rear side are foldably connected by two cross-rotating diagonal rods. The wheel frame assembly has an umbrella-like X-shaped foldable structure, with the four corners of the wheel frame assembly connected to the lower ends of the vertical poles, and the frame can be folded and unfolded by folding and unfolding the wheel frame assembly. The casters are mounted below the four corners of the wheel frame assembly, and the storage pocket is arranged in the frame and fixed to the four vertical poles. The handle assembly is arranged on the right side of the frame, and the lower end of the handle assembly is rotatably connected to the lower end of the two vertical poles on the front side or the rear side and can be folded along with the vertical poles. The present invention has a simple and reasonable structure, a small size when folded, and is convenient for storage and carrying. The universal wheels can be flexibly adjusted according to usage needs, and are flexible and convenient to operate.

Description

Technical Field

[0001] The invention belongs to the technical field of transportation tools and relates to a handcart, in particular to a foldable handcart. Background Art

[0002] Handcarts are a common means of transportation in daily life. They are mainly divided into shopping carts and transport carts. Shopping carts are used for shopping and outings and are mainly composed of a frame, casters, and bearings. Transport carts are agricultural transport tools with three main components: wheels, a frame, and brakes. As people's living standards improve, activities such as family shopping, road trips, and camping in the countryside are becoming more and more common. Handcarts are also widely used in outdoor places such as squares, beaches, parks, and courtyards, making it convenient for people to carry large amounts of supplies. However, traditional handcarts are large and cannot be folded, making them inconvenient to carry and store. To address this, handcarts are now designed to be foldable for easier storage.

[0003] Upon investigation, the existing Chinese patent number CN202221606025.2, "A Folding Handcart," includes a handle and a frame with wheels disposed below the frame. The frame includes a bottom frame side and an upper frame side, which are connected by vertical rods. An intermediate rod is disposed in the middle of the bottom frame side, and folding mechanisms are disposed at both ends of the intermediate rod. This handcart is easily foldable, meeting usage requirements, but is inconvenient to operate, is not compact enough when folded, and the casters cannot be adjusted, making it less than ideal for flexibility. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a foldable handcart with a simple structure and flexible and convenient operation in response to the above technical status quo.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a foldable handcart, characterized in that it includes a handle assembly, a foldable frame, casters and a storage pocket, the frame includes four vertical poles and a wheel frame assembly arranged in the front, back, left and right, the vertical poles are arranged above the wheel frame assembly, wherein the two vertical poles on the front side and the two vertical poles on the rear side are foldably connected by two cross-rotating oblique rods, the wheel frame assembly has an umbrella-shaped X-shaped foldable structure, the four corners of the wheel frame assembly are connected to the lower ends of the vertical poles, and the folding and unfolding of the frame are realized by the folding and unfolding of the wheel frame assembly; the casters are installed below the four corners of the wheel frame assembly, the storage pocket is arranged in the frame and fixed to the four vertical poles, the handle assembly is arranged on the front or rear side of the frame, the lower end of the handle assembly is rotatably connected to the lower ends of the two vertical poles on the front or rear side and can be folded along with the vertical poles.

[0006] Furthermore, the wheel frame assembly includes an upper nest, a lower nest, four long bones, four short bones, four support bones and four joints. One end of the long bone is pivotally connected to the upper nest, and the other end is pivotally connected to the top of the joint. One end of the short bone is pivotally connected to the middle of the long bone, and the other end is pivotally connected to the lower nest. One end of the support bone is pivotally connected to the lower part of the joint, and the other end is pivotally connected to the short bone. The caster is installed at the bottom of the joint.

[0007] Furthermore, a convex column is provided in the middle of the upper end surface of the lower nest, and a corresponding concave hole is provided in the middle of the lower end surface of the upper nest. When the wheel frame assembly is unfolded, the upper nest and the lower nest are exactly connected through the cooperation of the concave hole and the convex column, and the four long bones form an X shape on the same horizontal plane.

[0008] Furthermore, the caster adopts a universal wheel, which can be adjustably installed under the joint. A connecting cylinder is convexly provided on the upper end of the wheel seat of the universal wheel, and a slot is concavely provided at the bottom of the joint for inserting the connecting cylinder. An annular groove is formed on the outer periphery of the upper end of the connecting cylinder, and a mounting hole is provided on the joint at a position corresponding to the annular groove. A fastener passes through the mounting hole and interferes with the annular groove. A fixing hole is radially provided below the annular groove on the connecting cylinder, and a corresponding positioning hole is provided on the joint. An adjusting bolt passes through the positioning hole and is screwed into the fixing hole to position the direction of the universal wheel.

[0009] Furthermore, the four corners of the wheel frame assembly are detachably connected to the lower ends of the vertical poles, and the four vertical poles are symmetrically arranged front to back and left to right.

[0010] Furthermore, a clamp is fixedly provided at the lower end of the vertical pole, and the wheel frame assembly is detachably connected to the vertical pole through the cooperation of the joint and the clamp, wherein a T-shaped guide rail is longitudinally formed on the upper outer side of the joint, and a groove is formed on the lower outer side of the joint to form a strip plate with a certain elasticity, and a buckle is convexly provided on the middle part of the strip plate, and the inner side surface of the clamp is provided with a guide groove for sliding with the T-shaped guide rail, and the lower inner wall of the guide groove is recessed with a groove for cooperating with the buckle, and the clamp is plugged into the joint through the cooperation of the guide groove and the T-shaped guide rail, and is fixed to the joint through the cooperation of the groove and the buckle.

[0011] Furthermore, a slider that can slide up and down is sleeved on the vertical rod, the middle parts of the two oblique rods on the same side are pivotally connected, the upper end of the oblique rod is pivotally connected to the slider, and the lower end of the oblique rod is pivotally connected to the clamp at the lower end of the other vertical rod, and a limit block is provided on the vertical rod to limit the downward movement of the slider.

[0012] Furthermore, the handle assembly includes a handle, a telescopic rod, a center block and a pull rod, wherein the telescopic rod can be slid up and down through the center position of the center block, the handle is set at the top position of the telescopic rod, there are two pull rods, and an adapter is pivoted on the clamp at the lower end of the front or rear vertical rod, the lower end of the pull rod is pivoted to the adapter, and the upper end of the pull rod is pivoted to the center block.

[0013] Furthermore, the center block is a rectangular block, and the telescopic rods are two side by side. A through hole is provided in the middle of the center block for the telescopic rod to pass through and slide. A stop block is provided at the lower end of the telescopic rod to abut against the opening. Openings are recessed on both sides of the center block for the upper end of the pull rod to be inserted. The upper end of the pull rod is inserted into the opening and pivotally connected to the center block.

[0014] Furthermore, the adapter is arranged on the lower outer side of the clamp of the front or rear side vertical pole and is rotatably connected to the clamp. The side of the adapter is provided with a U-shaped groove for inserting the lower end of the pull rod. The lower end of the pull rod is inserted into the U-shaped groove and pivotally connected to the adapter. The handle is a C-shaped block. The lower end of the handle is provided with a socket for inserting the upper ends of the two telescopic rods. The handle is fixed to the telescopic rod by a fixing part.

[0015] Finally, the storage pocket is detachably fixed to the upright pole to form a storage assembly, and the wheel frame assembly can be folded separately and placed in the storage assembly.

[0016] Compared with the prior art, the advantages of the present invention are: the folding mechanism is integrated into the bottom of the product to further reduce the size after folding; the uprights and wheel frame assembly are easily disassembled, so that the entire frame can be folded as a whole or disassembled and folded to reduce the size for easy storage and carrying; the wheel frame assembly can also be folded separately and placed in the storage assembly, and the extra space in the storage assembly can be used to place other outdoor supplies; the universal wheels are flexibly adjustable, and the universal wheels can be put into a bending state or a directional state by simply rotating the adjustment bolt, thereby allowing the folding bicycle to enter a four-wheel directional state, a front wheel universal and rear wheel directional state, a front wheel directional and rear wheel universal state, or a four-wheel universal state to adapt to different usage environments or match the usage habits of different consumers. The present invention has a simple and reasonable structure, a small size after folding, and is easy to store and carry. The universal wheels can be flexibly adjusted according to usage needs, and are flexible and convenient to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of an embodiment of the present invention;

[0018] Figure 2 A front view of an embodiment of the present invention;

[0019] Figure 3 A top view of an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram of the structure of an embodiment of the present invention in a folded state;

[0021] Figure 5 This is a schematic diagram of the structure of an embodiment of the present invention in an unfolded state;

[0022] Figure 6 This is a schematic structural diagram of an embodiment of the present invention when the wheel frame assembly is disassembled;

[0023] Figure 7 for Figure 6 Schematic diagram of the structure in the folded state;

[0024] Figures 8a to 8d Schematic diagram of the assembly and folding principle of the wheel frame assembly according to an embodiment of the present invention, wherein a is the folded state, b is the beginning of unfolding, c is the unfolded state, and d is the assembled state;

[0025] Figure 9 Schematic diagram of the assembly of the chuck and the connector;

[0026] Figure 10 This is a cross-sectional view of the connector and the chuck after assembly;

[0027] Figure 11 This is a schematic diagram of the installation of the universal wheel;

[0028] Figure 12 This is a partial enlarged view of the upper end of the universal wheel;

[0029] Figures 13(1) to 13(4) Schematic diagram of the structure of the embodiment of the present invention in different states of universal wheel adjustment, including (1) four-wheel directional, (2) front wheel universal and rear wheel directional, (3) front wheel directional and rear wheel universal, (4) four-wheel universal;

[0030] Figure 14 This is a diagram of how the wheel frame assembly is stored after being folded. DETAILED DESCRIPTION

[0031] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0032] like Figures 1 to 14 As shown, a foldable handcart includes a handle assembly 4, a foldable frame A, casters 5 and a storage pocket 6. The frame A includes four vertical poles 1 and a wheel frame assembly 3 symmetrically arranged in the front and rear left and right directions. The vertical poles 1 are arranged above the wheel frame assembly 3, wherein the two vertical poles 1 on the front side and the two vertical poles 1 on the rear side are foldably connected by two cross-rotating oblique rods 2 respectively. The wheel frame assembly 3 has an umbrella-shaped X-shaped foldable structure, and the four corners of the wheel frame assembly 3 are detachably connected to the lower ends of the vertical poles 1, and the folding and unfolding of the frame A are realized by folding and unfolding the wheel frame assembly 3; the casters 5 adopt four universal wheels 5, which are adjustably mounted below the four corners of the wheel frame assembly 3, and the storage pocket 6 is detachably arranged in the frame A and fixed to the four vertical poles 1. The handle assembly 4 is arranged on the rear or front side of the frame A, and the lower end of the handle assembly 4 is rotatably connected to the lower ends of the two vertical poles 1 on the rear or front side and can be folded with the vertical poles 1.

[0033] The specific structure is as follows: the wheel frame assembly 3 includes an upper nest 31, a lower nest 32, four long bones 33, four short bones 34, four support bones 35, and four joints 8. One end of the long bone 33 is pivotally connected to the upper nest 31 and the other end is pivotally connected to the top of the joint 8. One end of the short bone 34 is pivotally connected to the middle of the long bone 33 and the other end is pivotally connected to the lower nest 32. One end of the support bone 35 is pivotally connected to the bottom of the joint 8 and the other end is pivotally connected to the short bone 34. The universal wheel 5 is mounted on the bottom of the joint 8. A protrusion 321 is provided in the middle of the upper end surface of the lower nest 32, and a corresponding recessed hole 311 is provided in the middle of the lower end surface of the upper nest 31. When the wheel frame assembly 3 is deployed, the upper and lower nests 31 and 32 are aligned through the engagement of the recessed hole 311 and the protrusion 321, and the four long bones 31 form an X shape on the same horizontal plane. A connecting cylinder 51 is protruding from the upper end of the wheel seat of the universal wheel 5. A slot for inserting the connecting cylinder 51 is recessed in the bottom of the connector 8. An annular groove 52 is formed on the outer circumference of the upper end of the connecting cylinder 51. A mounting hole 84 is provided on the connector 8 at a position corresponding to the annular groove 52. A fastener a passes through the mounting hole 84 and contacts the annular groove 52, thereby connecting the connecting cylinder 52 and the connector 8 together and preventing the universal wheel 5 from being dislodged from the connector 8. A fixing hole 53 is radially provided on the connecting cylinder 51 below the annular groove 52. A corresponding positioning hole 85 is provided on the connector 8. An adjusting bolt b passes through the positioning hole 85 and is screwed into the fixing hole 53 to position the direction of the universal wheel 5 and limit its rotation.

[0034] The lower end of the vertical rod 1 is fixed with a clamp 7, and the wheel frame assembly 3 is detachably connected to the vertical rod 1 through the cooperation of the joint 8 and the clamp 7. Its connection structure is: a T-shaped guide rail 81 is longitudinally formed on the upper outer side of the joint 8, and a groove is formed on the lower outer side of the joint 8 to form a strip plate 82 with a certain elasticity. A buckle 83 is convexly provided on the middle part of the strip plate 82. The inner side surface of the clamp 7 is provided with a guide groove 72 that slides with the T-shaped guide rail 81, and the lower inner wall of the guide groove 72 is recessed with a clamping groove 71 that cooperates with the buckle 83. The clamp 7 is plugged into the joint 8 through the cooperation of the guide groove 72 and the T-shaped guide rail 81, and is fixed to the joint 8 through the cooperation of the clamping groove 71 and the buckle 83. When the wheel frame assembly 3 needs to be disassembled, just press the strip plate 82 to disengage the buckle 83 from the clamping groove 71, and the joint 8 can be disengaged from the clamp 7. A slider 9 that can slide up and down is also sleeved on the vertical rod 1. The middle parts of the two oblique rods 2 on the same side are pivotally connected. The upper end of the oblique rod 2 is pivotally connected to the slider 9, and the lower end of the oblique rod 9 is pivotally connected to the clamp 8 at the lower end of the other vertical rod 1. A limit block 10 is provided on the vertical rod 1. The function of the limit block 10 is to limit the upward movement of the slider 9, thereby limiting the maximum distance between the two vertical rods 9.

[0035] The handle assembly 4 includes a handle 41, a telescopic rod 42, a center block 43, and a pull rod 44. The telescopic rod 42 is slidably inserted into the center of the center rod 43. The handle 41 is located at the top of the telescopic rod 42. There are two pull rods 44. An adapter 45 is pivotally connected to the clamp 7 at the lower end of the rear vertical rod 1. The lower end of the pull rod 44 is pivotally connected to the adapter 45, and the upper end of the pull rod 44 is pivotally connected to the center block 43. The center block 43 is a rectangular block. There are two telescopic rods 42 arranged side by side. A through hole 431 is provided in the middle of the center block 43 for the telescopic rod 42 to pass through and slide. A block is provided at the lower end of the telescopic rod 42 to abut against the through hole. Openings 432 are recessed on both sides of the center block 43 for the upper end of the pull rod 44 to be inserted. The upper end of the pull rod 44 is inserted into the opening and pivotally connected to the center block 43. The adapter 45 is arranged on the lower outer side of the clamp 7 of the rear or front side vertical pole 1 and is rotatably connected to the clamp 7. The side of the adapter 45 is provided with a U-shaped notch 451 for inserting the lower end of the pull rod 44. The lower end of the pull rod 44 is inserted into the U-shaped notch and is pivotally connected to the adapter 45. The handle 41 is a C-shaped block. The lower end of the handle 41 is provided with a socket for inserting the upper ends of two telescopic rods 42. The handle 41 is fixed to the telescopic rods 42 by screws. The storage pocket 6 is fixed to the vertical pole 1 to form a storage assembly B. The wheel frame assembly 3 can be folded separately and placed in the storage assembly B. Typically, the storage pocket 6 is made of a flexible material such as cloth or plastic and has a hollow, bottomed rectangular shape. The four corners are provided with loops for slipping onto the vertical pole 1. Alternatively, the four corners are provided with binding straps for tying to the vertical pole 1.

[0036] When in use, the folding bicycle can be unfolded by pulling apart the upright rod 1 along the radial direction of the upper nest 31 and pressing down the upper nest 31. Figure 5 By pulling the handle 41, the telescopic rod 42 can be pulled out from the central block 4, thereby driving the folding bicycle to move.

[0037] When adjusting the universal wheel 5, the corresponding universal wheel 5 can be put into a bent state by unscrewing the adjusting bolt b counterclockwise, and the corresponding universal wheel 5 can be put into a directional state by unscrewing the adjusting bolt b clockwise, thereby making the folding bicycle enter a four-wheel directional state as shown in FIG13(1), a front wheel universal and a rear wheel directional state as shown in FIG13(2), a front wheel directional and a rear wheel universal as shown in FIG13(3), or a four-wheel universal state as shown in FIG13(4) to adapt to different usage environments or match the usage habits of different consumers.

[0038] When disassembling and storing, press the strip plate 82 with the buckle 83 to separate the clamp 7 from the joint 8. After all four joints 8 are removed, the wheel frame assembly 3 is folded separately and placed in the storage assembly B. Figure 14 The extra space in the storage component B can be used to place other outdoor items, and the entire thing can be stored in the trunk for easy operation by the user.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A folding handcart, characterized by: The bicycle comprises a handle assembly, a foldable frame, casters and a storage pocket. The frame comprises four vertical poles arranged at the front, back, left and right sides and a wheel frame assembly. The vertical poles are arranged above the wheel frame assembly, wherein the two vertical poles on the front side and the two vertical poles on the rear side are foldably connected by two cross-rotating oblique rods. The wheel frame assembly has an umbrella-shaped X-shaped foldable structure. The four corners of the wheel frame assembly are connected to the lower ends of the vertical poles, and the folding and unfolding of the frame are achieved by folding and unfolding the wheel frame assembly. The casters are installed below the four corners of the wheel frame assembly. The storage pocket is arranged in the frame and fixed to the four vertical poles. The handle assembly is arranged at the front or rear side of the frame. The lower end of the handle assembly is rotatably connected to the lower ends of the two vertical poles on the front or rear side and can be folded along with the vertical poles. The wheel frame assembly includes an upper nest, a lower nest, four long bones, four short bones, four support bones and four joints, one end of the long bone is pivotally connected to the upper nest, and the other end is pivotally connected to the top of the joint, one end of the short bone is pivotally connected to the middle of the long bone, and the other end is pivotally connected to the lower nest, one end of the support bone is pivotally connected to the lower part of the joint, and the other end is pivotally connected to the short bone, and the caster is installed at the bottom of the joint; A convex column is provided in the middle of the upper end surface of the lower nest, and a corresponding concave hole is provided in the middle of the lower end surface of the upper nest. When the wheel frame assembly is unfolded, the upper and lower nests are exactly connected through the cooperation of the concave hole and the convex column, and the four long bones form an X shape on the same horizontal plane; The four corners of the wheel frame assembly are detachably connected to the lower ends of the vertical poles, and the four vertical poles are symmetrically arranged front to back and left to right; The lower end of the vertical rod is fixed with a chuck, and the wheel frame assembly is detachably connected to the vertical rod through the cooperation of the joint and the chuck, wherein the upper outer side of the joint is longitudinally formed with a T-shaped guide rail, the lower outer side of the joint is slotted to form a strip plate with a certain elasticity, the middle part of the strip plate is convexly provided with a buckle, the inner side surface of the chuck is provided with a guide groove that slides with the T-shaped guide rail, and the lower inner wall of the guide groove is concavely provided with a clamping groove that cooperates with the buckle, the chuck is plugged into the joint through the cooperation of the guide groove and the T-shaped guide rail, and is fixed to the joint through the cooperation of the clamping groove and the buckle; The wheel frame assembly can be folded separately and placed in the storage assembly.

2. The foldable handcart according to claim 1, characterized in that: The caster adopts a universal wheel, which can be adjusted and installed under the joint. A connecting cylinder is convexly provided on the upper end of the wheel seat of the universal wheel, and a slot for inserting the connecting cylinder is concavely provided on the bottom of the joint. An annular groove is formed on the outer periphery of the upper end of the connecting cylinder. A mounting hole is provided on the joint at a position corresponding to the annular groove. A fastener passes through the mounting hole and contacts the annular groove. A fixing hole is radially provided below the annular groove on the connecting cylinder. A corresponding positioning hole is provided on the joint. An adjusting bolt passes through the positioning hole and is screwed into the fixing hole to position the direction of the universal wheel.

3. The foldable handcart according to claim 1, characterized in that: The vertical rod is also provided with a slider that can slide up and down. The middle parts of the two oblique rods on the same side are pivotally connected. The upper end of the oblique rod is pivotally connected to the slider, and the lower end of the oblique rod is pivotally connected to the clamp at the lower end of the other vertical rod. A limit block is provided on the vertical rod to limit the downward movement of the slider.

4. The foldable handcart according to claim 1, characterized in that: The handle assembly includes a handle, a telescopic rod, a center block and a pull rod, wherein the telescopic rod can be slid up and down through the center position of the center block, the handle is set at the top position of the telescopic rod, there are two pull rods, and an adapter is pivoted on the clamp at the lower end of the front or rear vertical rod. The lower end of the pull rod is pivoted to the adapter, and the upper end of the pull rod is pivoted to the center block.

5. The foldable handcart according to claim 4, characterized in that: The center block is a rectangular block, and the telescopic rods are two side by side. A through hole is provided in the middle of the center block for the telescopic rod to pass through and slide. A stop block is provided at the lower end of the telescopic rod to abut against the opening. Openings are recessed on both sides of the center block for the upper end of the pull rod to be inserted. The upper end of the pull rod is inserted into the opening and pivotally connected to the center block.

6. The foldable handcart according to claim 5, characterized in that: The adapter is arranged on the lower outer side of the clamp of the front or rear side vertical pole and is rotatably connected to the clamp. A U-shaped groove is provided on the side of the adapter for inserting the lower end of the pull rod. The lower end of the pull rod is inserted into the U-shaped groove and pivotally connected to the adapter. The handle is a C-shaped block. The lower end of the handle is provided with a socket for inserting the upper ends of two telescopic rods. The handle is fixed to the telescopic rod by a fixing piece.

7. The foldable handcart according to any one of claims 1 to 6, characterized in that: The storage pocket is detachably fixed to the upright pole to form a storage assembly.

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