Wheelchair side frame assembly and folding wheelchair

Abstract

The utility model provides a wheelchair side frame assembly, which is characterized in that a handrail frame adopts a rotary design, the base part of the handrail frame is rotationally connected with a side frame through a pin structure, a limiting component is arranged on the basis, and two limiting points are arranged at the two ends of the limiting component at the positions close to a seat plate cross rod and a chair back vertical rod; the limiting pin is arranged near the rotating pin joint position of the base portion of the armrest frame, the limiting pin reaches the limiting point of the limiting component when the armrest frame rotates to the limiting position, the limiting pin and the limiting point are locked in a matched mode, and therefore the armrest frame is fixed to the limiting position. When a user gets on or gets off the wheelchair, the armrest frame can be rotated to the angle approximately parallel to the seat plate transverse rod and the angle approximately parallel to the chair back vertical rod, the armrest frame can be rotated to the angle approximately parallel to the chair back when the user gets on or gets off the wheelchair, and therefore protection and limiting of one side face of the wheelchair to the user are completely relieved, and the armrest frame can be rotated to return to the angle approximately parallel to the seat plate after getting on or off the wheelchair. The utility model further provides a folding wheelchair.

Description

Technical Field

[0001] The utility model relates to the technical field of medical equipment, in particular to a wheelchair side frame assembly and a foldable wheelchair. Background Art

[0002] With the continuous increase in the number of elderly people in China and the increasing demand for diversified travel by special disabled groups, electric wheelchairs have gradually become an indispensable means of transportation in the market. Electric wheelchairs are a type of mechanical equipment equipped with an electric drive device based on a traditional hand-cranked wheelchair. Most electric wheelchairs are mainly composed of a wheelchair frame, a drive motor, a controller, and a battery. Unlike traditional wheelchairs, electric wheelchairs have a special interactive structure that allows the wheelchair to move through manual or other forms of instructions, and can complete the action alone without relying on other external assistance.

[0003] The wheelchair bracket usually includes a side frame, a bottom bracket, a seat bracket, a wheel bracket and other parts. The specific bracket distribution structure varies depending on the technical requirements of the wheelchair's load-bearing requirements, folding and storage requirements, etc. However, there are some problems in the use of general wheelchairs or electric wheelchairs. Specifically, when the user gets on and off the wheelchair, during normal use, the user can basically only get on and off between the armrests on both sides of the wheelchair. This process of getting on and off can easily give the wheelchair a thrust parallel to its original direction of travel, causing the wheelchair to move during the user's getting on and off, posing a great safety hazard. To solve this problem, some wheelchair designs use a specially set simple brake mechanism to temporarily lock the wheelchair's wheels to prevent position movement. However, even with this structure, there are still cases where the user does not use the brake or uses the brake improperly, and the use of this structure often requires manual operation, which still causes inconvenience and safety risks.

[0004] In summary, the existing foldable wheelchair boarding and disembarking design has technical problems with obvious safety risks. Utility Model Content

[0005] The technical problem to be solved by the utility model is that the existing design of getting on and off the folding wheelchair has obvious safety risks.

[0006] To solve the above problems, the utility model provides a wheelchair side frame assembly, including a side frame body for connecting wheels and an armrest frame connected to the side frame body, the side frame body including an integrally connected seat plate cross bar and a seat back vertical bar, the base of the armrest frame is pinned to the transition position of the seat plate cross bar and the seat back vertical bar, a limiting member is connected between the seat plate cross bar and the seat back vertical bar, for limiting the angular range of rotation of the armrest frame around the pinned position, a limiting pin is provided at the base of the armrest frame, and limited position structure is provided at positions adjacent to the seat plate cross bar and the seat back vertical bar at both ends of the limiting member, the limiting position structure is used to cooperate with the limiting pin to lock the angular position of the armrest frame, so that the armrest frame has a rotation range of more than 90°.

[0007] The utility model provides a wheelchair side frame assembly, wherein the armrest frame of the side frame adopts a rotating design, the base of the armrest frame is rotatably connected to the transition position between the seat plate cross bar and the seat back vertical bar of the side frame through a pin structure, and a limiting component is arranged on the basis of the rotating connection structure, two limiting points are arranged at both ends of the limiting component at positions adjacent to the seat plate cross bar and the seat back vertical bar, and a limiting pin is arranged near the rotating pin connection position of the armrest frame base, and the limiting pin reaches the limiting point of the limiting component when the armrest frame rotates to the limit position, and forms a matching lock with the limiting point, thereby fixing the armrest frame to the limit position. The armrest frame can be rotated to the position so that the top is approximately parallel to the horizontal bar of the seat plate and close to the vertical bar of the chair back, so that it has a rotation range of more than 90 degrees. Therefore, when the user gets on or off the vehicle, the armrest frame can be directly rotated to an angle close to the chair back, thereby completely removing the protection limit on the side of the wheelchair facing the user. After getting on or off the vehicle, the armrest frame can be rotated back to an angle approximately parallel to the seat plate. In this way, the user can easily get on or off the vehicle from the side of the wheelchair, avoiding the safety hazard that may occur when getting on or off the vehicle from the front due to the rotation of the wheels, effectively solving the technical problem that the existing design of getting on and off the vehicle of the folding wheelchair has obvious safety risks.

[0008] As a preferred solution, the limiting member is an arc-shaped limiting rod, and the arc shape of the limiting rod coincides with the rotation trajectory of the limiting pin, which is used to limit and guide the rotation of the handrail. This design optimizes the structural design of the limiting member, adopts an arc-shaped overall design, and makes its shape consistent with the movement trajectory of the limiting pin when the handrail rotates, so that the guiding and limiting of the handrail during the rotation process can be formed through the sliding cooperation between the limiting pin and the limiting rod, ensuring the accurate position of the limiting pin when it rotates to the limit point position, and ensuring the accurate cooperation between the limiting pin and the limit point.

[0009] As a preferred solution, a through circular arc-shaped slot is provided at the center axis position of the limit rod, and the limit point structure is two limit through holes located at both ends of the circular arc-shaped slot, and the side edges of the limit through holes are connected to the circular arc-shaped slot. This design optimizes the specific structural design of the cooperation between the limit rod and the limit pin, wherein a circular arc-shaped slot consistent with its shape is provided at the center axis position of the limit rod, and the two limit points are two limit through holes located at both ends of the slot, respectively, the through holes and the slot are connected to each other, the limit pin is laterally accommodated in the limit slot, and can slide to the limit through hole along the shape of the limit slot, providing a preferred feasible solution based on the structure of the above design, with a simple structure, easy assembly, and smooth sliding cooperation.

[0010] As a preferred solution, the limit pin includes a radially expanded positioning end of an integrally connected pin rod, the aperture of the limit through hole is larger than the groove width of the arc-shaped slide groove, the base of the handrail frame is provided with a sliding through hole, and the pin rod of the limit pin is axially slidably installed in the sliding through hole, so as to form a concave-convex positioning fit between the positioning end and the limit through hole by pulling the limit pin.

[0011] This design optimizes the structure of the limit pin and the way it cooperates with the handrail frame. In view of the pin shaft structure of the limit pin itself, a sliding through hole is set at the installation position of the handrail frame, and the limit pin can be accommodated therein for axial movement. An enlarged positioning end is set at the end of the limit pin that cooperates with the limit through hole, and the through hole of the limit through hole itself is larger than the circular arc slide groove. During the sliding of the limit pin in the slide groove, the pin rod section of the limit pin is accommodated in the circular arc slide groove, and when the limit pin reaches the limit through hole, the axial position of the limit pin changes, so that its positioning end sinks into the limit through hole, thereby realizing the positioning of the limit pin or the rotation angle of the handrail frame.

[0012] As a preferred solution, the pin rod is threadedly connected with a radially enlarged limit key at the other end opposite to the positioning end head, which is used to limit the axial position of the limit pin to prevent the limit pin from falling out of the sliding through hole. This design is aimed at the structure in which the limit pin can move axially in the sliding through hole in the above design. A limit key similar to the structure of the positioning end head is set at the other end of the limit pin opposite to the positioning end head, but the limit key and the pin rod are threadedly matched. This structure facilitates the assembly of the limit pin, and the limit pin can be easily inserted into the sliding through hole. Moreover, since both pin rods have an enlarged structure, the limit rod can be prevented from falling out of the sliding through hole.

[0013] As a preferred solution, the inner edge of the sliding through hole is provided with an inwardly protruding limit boss at one end close to the positioning end head, and a compression spring is provided on the outer periphery of the pin rod, and the two ends of the compression spring are respectively against the limit boss and the inner end surface of the limit key, so that the elastic potential energy of the limit pin moving toward one end of the limit key is provided by the compression spring.

[0014] The design is based on the above structure and is designed to cooperate with the limit pin that can slide axially in the sliding through hole. A compression spring is sleeved on the pin rod. Correspondingly, a raised limit boss is set in the sliding through hole as a support for the compression spring. The other end of the compression spring is against the inner end of the limit key. The spring provides a movement trend for the limit pin to move toward one end of the limit key. That is, when the limit pin reaches the limit through hole at the end of the arc-shaped slide groove, the limit pin can automatically sink the positioning end into the limit through hole under the action of elastic force to form a limit, so that the handrail frame can be automatically limited and fixed at two extreme angle positions.

[0015] As a preferred solution, the handrail frame includes an integrally connected diagonal support rod and a handrail crossbar, and the base of the diagonal support rod is provided with the limit pin. This design optimizes the structural design of the handrail frame, including a diagonal support rod for connection and a handrail crossbar for supporting the user's body, the two parts are integrally connected, and the structure is simple and practical.

[0016] As a preferred solution, the two ends of the limiting member are respectively connected and fixed integrally with the seat crossbar and the seat back vertical rod. This design optimizes the connection design between the limiting member and the seat crossbar and the seat back vertical rod of the side frame, adopting an integrally connected and fixed structure, thereby ensuring the firmness of the limiting rod structure and fully ensuring the stability of the limiting rod's guiding and limiting action on the armrest frame.

[0017] The utility model also provides a foldable wheelchair, comprising a wheelchair side frame assembly, a middle connecting rod assembly, a driving assembly, a wheel assembly, a seat plate and a backrest, wherein the wheelchair side frame assembly is any of the above wheelchair bracket assemblies. Since the above wheelchair side frame assembly has the above beneficial effects, a foldable wheelchair equipped with the wheelchair side frame assembly should also have corresponding beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the overall structure of a foldable wheelchair provided by the utility model;

[0019] Figure 2 for Figure 1 A schematic diagram of the partial structure of the handrail frame position of the middle wheelchair side frame assembly;

[0020] Figure 3 for Figure 2 A schematic cross-sectional structure diagram of the position of the limit pin of the middle handrail frame;

[0021] in, Figure 1-Figure 3 middle:

[0022] 1. Armrest frame; 1-1. Armrest crossbar; 1-2. Diagonal support rod; 1-3. Sliding through hole; 1-4. Limiting boss; 2-1. Seat crossbar; 2-2. Chair back vertical rod; 3. Limiting rod; 3-1. Limiting through hole; 3-2. Arc-shaped slide groove; 4. Limiting pin; 4-1. Pin rod; 4-2. Positioning end; 4-3. Limiting key; 4-4. Compression spring. DETAILED DESCRIPTION

[0023] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0024] Before explaining the working principle of the present invention in detail, the description of the present invention needs to be further explained: In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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 a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, an indirect connection through an intermediate medium, or a welding connection between 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.

[0026] refer to Figure 1-Figure 3 The following embodiments are described, Figure 1 A schematic diagram of the overall structure of a foldable wheelchair provided by the utility model; Figure 2 for Figure 1 A schematic diagram of the partial structure of the handrail frame position of the middle wheelchair side frame assembly; Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure of the limit pin position of the middle handrail frame.

[0027] A wheelchair side frame assembly provided in this embodiment includes a side frame body for connecting wheels and an armrest frame 1 connected to the side frame body, the side frame body includes a seat cross bar 2-1 and a seat back vertical bar 2-2 that are integrally connected, the base of the armrest frame 1 is pinned to the seat cross bar 2-1 and the seat back vertical bar 2-2 at a transition position, a limiting member is connected between the seat cross bar 2-1 and the seat back vertical bar 2-2, for limiting the angle range of rotation of the armrest frame 1 around the pinned position, a limiting pin 4 is provided at the base of the armrest frame 1, and a limiting position structure is provided at positions adjacent to the seat cross bar 2-1 and the seat back vertical bar 2-2 at both ends of the limiting member, the limiting position structure is used to cooperate with the limiting pin 4 to lock the angular position of the armrest frame 1, so that the armrest frame 1 has a rotation range of more than 90°.

[0028] The utility model provides a wheelchair side frame assembly, in which the armrest frame 1 of the side frame adopts a rotating design, the base of the armrest frame 1 and the transition position between the seat plate cross bar 2-1 and the seat back vertical bar 2-2 of the side frame are rotatably connected through a pin structure, and a limiting component is arranged on the basis of the rotating connection structure, two limiting points are arranged at both ends of the limiting component at positions adjacent to the seat plate cross bar 2-1 and the seat back vertical bar 2-2, and a limiting pin 4 is arranged near the rotating pin connection position of the base of the armrest frame 1. When the armrest frame 1 rotates to the limit position, the limiting pin 4 reaches the limit point of the limiting component and forms a matching lock with the limit point, thereby fixing the armrest frame 1 to the limit position. The position of the limit point itself is just right for rotating the armrest frame 1 to the top to reach an angle that is approximately parallel to the seat plate cross bar 2-1 and close to the seat back vertical bar 2-2, so that it has a rotation range greater than 90°. Therefore, when the user gets on or off the vehicle, the armrest frame 1 can be directly rotated to an angle close to the seat back, thereby completely releasing the protective limit on the side of the wheelchair facing the user. After getting on or off the vehicle, the armrest frame 1 can be rotated back to an angle that is approximately parallel to the seat plate. In this way, the user can easily get on or off the vehicle from the side of the wheelchair, avoiding the safety hazard that may occur when getting on or off the vehicle from the front due to the rotation of the wheels, effectively solving the technical problem that the existing design of getting on and off the vehicle for folding wheelchairs has obvious safety risks.

[0029] In the technical solution provided in this embodiment, the limiting member is an arc-shaped limiting rod 3, and the arc shape of the limiting rod 3 coincides with the rotation trajectory of the limiting pin 4, which is used to limit the rotation of the handrail frame 1. This design optimizes the structural design of the limiting member, adopts an arc-shaped overall design, and makes its shape consistent with the motion trajectory of the limiting pin 4 when the handrail frame 1 rotates, so that the guiding and limiting of the handrail frame 1 during the rotation process can be formed through the sliding cooperation between the limiting pin 4 and the limiting rod 3, ensuring the accurate position of the limiting pin 4 when it rotates to the limit point position, and ensuring the accurate cooperation between the limiting pin 4 and the limit point.

[0030] In the technical solution provided by this embodiment, a through circular arc-shaped slot 3-2 is provided at the central axis position of the limit rod 3, and the limit point structure is two limit through holes 3-1 located at both ends of the circular arc-shaped slot 3-2, and the side edge of the limit through hole 3-1 is connected to the circular arc-shaped slot 3-2. This design optimizes the specific structural design of the cooperation between the limit rod 3 and the limit pin 4, wherein a circular arc-shaped slot 3-2 consistent with its appearance is provided at the central axis position of the limit rod 3, and the two limit points are two limit through holes 3-1 located at both ends of the slot, the through holes and the slot are connected to each other, and the limit pin 4 is laterally accommodated in the limit slot and can slide to the limit through hole 3-1 along the shape of the limit slot, providing a preferred feasible solution based on the structure of the above design, with a simple structure, easy assembly, and smooth sliding cooperation.

[0031] In the technical solution provided in this embodiment, the limit pin 4 includes an integrally connected pin rod 4-1 and a radially enlarged positioning end 4-2, the aperture of the limit hole 3-1 is larger than the groove width of the arc-shaped slide groove 3-2, and a sliding through hole 1-3 is provided at the base of the handrail frame 1. The pin rod 4-1 of the limit pin 4 is axially slidably installed in the sliding through hole 1-3, and is used to form a concave-convex positioning fit between the positioning end 4-2 and the limit through hole 3-1 by pulling the limit pin 4.

[0032] This design optimizes the structure of the limit pin 4 and the matching mode between it and the handrail frame 1. In view of the pin shaft structure of the limit pin 4 itself, a sliding through hole 1-3 is set at the installation position of the handrail frame 1, and the limit pin 4 can be accommodated therein for axial movement. An enlarged positioning end 4-2 is set at the end of the limit pin 4 that matches with the limit through hole 3-1, and the through hole of the limit through hole 3-1 itself is larger than the circular arc slide groove 3-2. During the sliding of the limit pin 4 in the slide groove, the pin rod 4-1 section of the limit pin 4 is accommodated in the circular arc slide groove 3-2, and when the limit pin 4 reaches the limit through hole 3-1, the axial position of the limit pin 4 changes, so that its positioning end 4-2 sinks into the limit through hole 3-1, thereby realizing the positioning of the limit pin 4 or the handrail frame 1 at the rotation angle.

[0033] In the technical solution provided in this embodiment, the pin rod 4-1 is threadedly connected with a radially enlarged limit key 4-3 at the other end opposite to the positioning end head 4-2, which is used to limit the axial position of the limit pin 4 to prevent the limit pin 4 from falling out of the sliding through hole 1-3. This design is aimed at the structure in which the limit pin 4 can move axially in the sliding through hole 1-3 in the above design. A limit key 4-3 similar to the structure of the positioning end head 4-2 is set at the other end of the limit pin 4 opposite to the positioning end head 4-2, but the limit key 4-3 is threadedly matched with the pin rod 4-1, so that the assembly of the limit pin 4 is convenient, and the limit pin 4 can be inserted into the sliding through hole 1-3 more easily. Moreover, since both ends of the pin rod 4-1 have an enlarged structure, the limit rod 3 can be prevented from falling out of the sliding through hole 1-3.

[0034] In the technical solution provided in this embodiment, an inner edge of the sliding through hole 1-3 is provided with an inwardly protruding limit boss 1-4 at one end close to the positioning end head 4-2, and a compression spring 4-4 ​​is sleeved on the outer periphery of the pin rod 4-1, and the two ends of the compression spring 4-4 ​​are respectively abutted against the limit boss 1-4 and the inner end faces of the limit key 4-3, and the compression spring 4-4 ​​provides elastic potential energy for the limit pin 4 to move toward one end of the limit key 4-3.

[0035] This design is based on the technical solution structure of the above-mentioned embodiment, and is designed to cooperate with the limit pin 4 that can slide axially in the sliding through hole 1-3. A compression spring 4-4 ​​is sleeved on the pin rod 4-1, and correspondingly, a raised limit boss 1-4 is set in the sliding through hole 1-3 to support the compression spring 4-4. The other end of the compression spring 4-4 ​​is against the inner end of the limit key 4-3, and the spring provides a movement trend for the limit pin 4 to move toward one end of the limit key 4-3. That is, when the limit pin 4 reaches the limit through hole 3-1 at the end of the arc-shaped slide groove 3-2, the limit pin 4 can automatically sink the positioning end 4-2 into the limit through hole 3-1 under the action of elastic force to form a limit, so that the handrail frame 1 can obtain the effect of automatic limit fixation at two extreme angle positions.

[0036] In the technical solution provided in this embodiment, the handrail frame 1 includes an integrally connected diagonal brace 1-2 and a handrail crossbar 1-1, and a limit pin 4 is provided at the base of the diagonal brace 1-2. This design optimizes the structural design of the handrail frame 1, including the diagonal brace 1-2 for connection and the handrail crossbar 1-1 for supporting the user's body, the two parts are integrally connected, and the structure is simple and practical.

[0037] In the technical solution provided in this embodiment, the two ends of the limiting member are respectively connected and fixed integrally with the seat cross bar 2-1 and the seat back vertical bar 2-2. This design optimizes the connection design between the limiting member and the seat cross bar 2-1 and the seat back vertical bar 2-2 of the side frame, adopting an integrally connected and fixed structure, thereby ensuring the firmness of the limiting rod 3 structure and fully ensuring the stability of the guiding and limiting action of the limiting rod 3 on the armrest frame 1.

[0038] The embodiment of the utility model further provides a foldable wheelchair, comprising a wheelchair side frame assembly, a middle connecting rod assembly, a driving assembly, a wheel assembly, a seat plate and a backrest, wherein the wheelchair side frame assembly is the wheelchair bracket assembly in any of the above embodiments. Since the above wheelchair side frame assembly has the above beneficial effects, a foldable wheelchair equipped with the wheelchair side frame assembly should also have corresponding beneficial effects.

[0039] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the utility model.

Claims

1. A wheelchair side frame assembly, comprising a side frame body for connecting a wheel and an armrest frame (1) connected to the side frame body, wherein the side frame body comprises a seat plate cross bar (2-1) and a seat back vertical bar (2-2) connected in an integral manner, characterized in that: The base of the armrest frame (1) is pin-connected with the seat cross bar (2-1) and the chair back vertical bar (2-2) at the transition position; a limiting component is connected between the seat cross bar (2-1) and the chair back vertical bar (2-2) for limiting the angle range of rotation of the armrest frame (1) around the pin-connected position; a limiting pin (4) is provided at the base of the armrest frame (1); and limiting position structures are provided at positions adjacent to the seat cross bar (2-1) and the chair back vertical bar (2-2) at both ends of the limiting component; the limiting position structure is used to cooperate with the limiting pin (4) to lock the angular position of the armrest frame (1), so that the armrest frame (1) has a rotation range of more than 90°.

2. The wheelchair side frame assembly according to claim 1, characterized in that: The limiting component is an arc-shaped limiting rod (3), the arc shape of the limiting rod (3) coincides with the rotation trajectory of the limiting pin (4), and is used to limit and guide the rotation movement of the handrail frame (1).

3. The wheelchair side frame assembly according to claim 2, characterized in that: A through arc-shaped sliding groove (3-2) is arranged at the central axis position of the limiting rod (3); the limiting point structure is two limiting through holes (3-1) located at both ends of the arc-shaped sliding groove (3-2); and the side edges of the limiting through holes (3-1) are connected to the arc-shaped sliding groove (3-2).

4. The wheelchair side frame assembly according to claim 3, characterized in that: The limit pin (4) comprises a radially enlarged positioning end (4-2) connected to an integral pin rod (4-1); the aperture of the limit through hole (3-1) is larger than the slot width of the arc-shaped slide groove (3-2); the base of the handrail frame (1) is provided with a sliding through hole (1-3); the pin rod (4-1) of the limit pin (4) is axially slidably installed in the sliding through hole (1-3), and is used to form a concave-convex positioning fit between the positioning end (4-2) and the limit through hole (3-1) by pulling the limit pin (4).

5. The wheelchair side frame assembly according to claim 4, characterized in that: The pin rod (4-1) is threadedly connected to a radially expanded limit key (4-3) at the other end opposite to the positioning end head (4-2) for limiting the axial position of the limit pin (4) to prevent the limit pin (4) from falling out of the sliding through hole (1-3).

6. The wheelchair side frame assembly according to claim 5, characterized in that: The inner edge of the sliding through hole (1-3) is provided with an inwardly protruding limiting boss (1-4) at one end close to the positioning end head (4-2); a compression spring (4-4) is sleeved on the outer periphery of the pin rod (4-1); the two ends of the compression spring (4-4) respectively abut against the limiting boss (1-4) and the inner end surface of the limiting key (4-3); and the compression spring (4-4) provides elastic potential energy for the limiting pin (4) to move toward one end of the limiting key (4-3).

7. The wheelchair side frame assembly according to any one of claims 1 to 6, characterized in that: The handrail frame (1) comprises an integrally connected diagonal support rod (1-2) and a handrail crossbar (1-1), and the limiting pin (4) is arranged at the base of the diagonal support rod (1-2).

8. The wheelchair side frame assembly according to claim 7, characterized in that: The two ends of the position-limiting component are respectively connected and fixed integrally with the seat plate crossbar (2-1) and the chair back vertical bar (2-2).

9. A foldable wheelchair, comprising a wheelchair side frame assembly, a middle connecting rod assembly, a drive assembly, a wheel assembly, a seat plate and a backrest, characterized in that: The wheelchair side frame assembly is the wheelchair side frame assembly as described in any one of claims 1-8.

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