Rotation positioning mechanism of wheelchair

Abstract

The present invention relates to a rotation positioning mechanism of a wheelchair, which is used for the seat of the wheelchair to rotate relative to the chassis of the wheelchair. The rotation mechanism comprises a seat bottom plate, a rotating shaft, a chassis and a locking unit. The seat of the wheelchair is fixed on the seat bottom plate, the upper end of the rotating shaft is fixed on the seat bottom plate, and the lower end is rotatably connected to the chassis. A positioning hole is provided on the chassis. The locking unit comprises a handle and a guide pin. One end of the handle is hinged to the middle part of the rotating shaft, and the guide pin is provided in the middle part of the handle. When the handle is rotated, the lower end of the guide pin can be inserted into the positioning hole. The rotation mechanism of the present invention has a simple structure and is easy to lock and unlock the rotating shaft and the chassis.

Description

Technical Field

[0001] The invention relates to a rotating mechanism of a wheelchair, and belongs to the technical field of wheelchair structure design. Background Art

[0002] Electric wheelchairs are usually rear-wheel drive with universal wheels at the front. Electric wheelchairs of this design have poor passability on complex roads. Due to the limitation of turning radius, existing wheelchairs have difficulty turning around on narrow roads. Wheelchairs with a rotating function can overcome the above problems. When passing through complex roads, you only need to rotate the seat 180° to turn it into front-wheel drive, which can enhance the passability on complex roads. When turning around on narrow roads, you only need to rotate the seat to achieve it, getting rid of the limitation of turning radius. However, the existing wheelchairs with a rotating function, especially those with a rotary drive function, are combined with the body of the wheelchair by a relatively complex mechanical connection. The seat and the body become a whole and cannot be separated unless they are mechanically disassembled. Therefore, it is inconvenient to carry, transport and repair. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention provides a rotating mechanism of a wheelchair which has a simple structure and is easy to lock and unlock.

[0004] In order to achieve the above-mentioned purpose, the technical solution proposed in the present invention is: a rotation positioning mechanism of a wheelchair, which is used for the seat of the wheelchair to rotate relative to the chassis of the wheelchair, and the rotation positioning mechanism includes a seat bottom plate, a rotating shaft, a chassis and a locking unit. The seat of the wheelchair is fixed to the seat bottom plate, the upper end of the rotating shaft is fixed to the seat bottom plate, and the lower end is rotatably connected to the chassis, and a positioning hole is provided on the chassis. The locking unit includes a handle, a guide pin, a locking pin frame and a connecting plate, one end of the locking pin frame is fixed to the rotating shaft, and the other end is provided with a guide hole. The lower end of the connecting plate is hinged to the locking pin frame, and the upper end is hinged to one end of the handle; the guide pin is hinged to the handle and is arranged at a position where the handle and the positioning hole are adapted, and is slidably connected in the guide hole. The handle rotates downward around the hinge point with the connecting plate, and the lower end of the guide pin can be inserted into the positioning hole, and the seat bottom plate is positioned on the chassis.

[0005] The locking unit also includes a spring, which is sleeved on the guide pin, with the upper end of the spring abutting against the lock pin frame and the lower end abutting against the guide pin, and the elastic force of the spring causes the guide pin to extend downward.

[0006] There are two positioning holes, and the two positioning holes are respectively arranged on a positioning seat, and the two positioning seats are symmetrically arranged on the chassis on both sides of the relative rotating shaft.

[0007] The rotation positioning mechanism also includes an anti-rotation frame, which is fixed on the chassis and located at one side of the positioning seat. When the lock pin frame is against the anti-rotation frame, the lower end of the guide pin is inserted into the positioning hole.

[0008] A vertical plate is extended upward from one side of the positioning seat. When one side of the locking pin frame is against the vertical plate, the lower end of the guide pin is inserted into the positioning hole.

[0009] The bottom of the lock pin frame is provided with a groove at the guide hole, the lower end of the guide pin is connected with a spring retaining ring, the upper end of the spring abuts against the bottom surface of the groove, and the lower end abuts against the spring retaining ring.

[0010] The lock pin frame is provided with a connecting hole, which is located at the other end of the lock pin frame relative to the guide hole, and the direction of the line connecting the center of the connecting hole and the center of the guide hole is the length direction of the lock pin frame. A first screw hole connected to the connecting hole is provided on one side or on both sides of the connecting hole, and the first screw hole is located in the radial direction of the connecting hole perpendicular to the length direction of the lock pin frame; the rotating shaft is provided with a connecting part adapted to the connecting hole, and an axially arranged waist-shaped groove is provided at the radial position of the connecting part corresponding to the first screw hole, and a positioning shoulder is provided at the lower end of the connecting part, the connecting hole of the lock pin frame is sleeved on the connecting part of the rotating shaft and axially positioned on the positioning shoulder, the screw is screwed into the first screw hole and the end is tightly against the bottom surface of the waist-shaped groove, so that the lock pin frame is fixed on the rotating shaft.

[0011] The lock pin frame is also provided with a second screw hole, which is located in the axial direction of the same connecting hole as the first screw hole; a through hole is provided at the lower end of the connecting plate, and a screw passes through the through hole and is screwed into the second screw hole to connect the connecting plate to the lock pin frame; when the second screw hole is arranged below the first screw hole, the screw screwed into the first screw hole sinks into the countersunk hole corresponding to the first screw hole.

[0012] The handle is provided with two side ears at one end close to the rotating shaft. The two side ears are symmetrically arranged on the two sides of the rotating shaft and are respectively hinged to a connecting plate.

[0013] The seat bottom plate is provided with an offset cone sleeve, and the upper end of the rotating shaft is provided with a cone surface adapted to the taper of the cone sleeve. The seat bottom plate is pluggable and relatively non-rotatably connected to the upper end of the rotating shaft through the combination of the cone sleeve and the cone surface.

[0014] The lower end of the rotating shaft is rotatably connected to the chassis via a tapered roller bearing.

[0015] The beneficial effects of the present invention are:

[0016] The rotating mechanism of the present invention realizes the locking and unlocking operations between the rotating shaft and the chassis through a simple handle and guide pin structure, and has a simple structure and is easy to operate.

[0017] The invention can make the seat rotate 180 degrees, that is, the rear-wheel drive can be changed into the front-wheel drive, and the passability on complex roads can be enhanced.

[0018] The seat in the present invention is only connected to the rotating shaft by plugging and unplugging, which is convenient for disassembly; the seat can be tilted back by a small angle through the tapered sleeve and the taper of the rotating shaft, making the seat more comfortable, and at the same time, the seat and the rotating shaft can rotate synchronously. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0021] Figure 3 for Figure 2 Schematic diagram of unlocking the middle locking unit;

[0022] Figure 4 for Figure 2 Diagram of the middle seat tilt;

[0023] Figure 5 for Figure 2 A partial enlarged view of the middle guide pin portion;

[0024] Figure 6 for Figure 2 A partial enlarged view of the middle connecting plate;

[0025] Figure 7 for Figure 2 Schematic diagram of the middle handle structure;

[0026] Figure 8 for Figure 1 Schematic diagram of the connection between the central shaft and the lock pin frame;

[0027] Fig. 9 for Figure 1 Schematic diagram of the structure of the middle lock pin frame;

[0028] Fig.10 This is a front view of the anti-rotation frame in Example 3;

[0029] Fig.11 This is a top view of the anti-rotation frame in Example 3.

[0030] 1-seat base, 2-handle, 21-side ear, 3-taper sleeve, 4-guide pin, 5-spring, 6-tapered roller bearing, 7-chassis, 8-locking pin frame, 81-connecting hole, 82-first screw hole, 83-second screw hole, 84-waist-shaped groove, 85-positioning shoulder, 86-connecting part, 87-guide hole, 9-anti-rotation frame, 10-connecting plate, 11-rotating shaft, 12-spring retaining ring, 13-groove, 14-positioning seat, 15-vertical plate, 16-positioning hole. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Embodiment 1

[0033] like Figure 1 As shown, a rotation positioning mechanism of a wheelchair of this embodiment is used for the seat of the wheelchair to rotate relative to the chassis of the wheelchair. The rotation positioning mechanism includes a seat bottom plate 1, a rotating shaft 11, a chassis 7 and a locking unit. The locking unit includes a handle 2, a guide pin 4, a locking pin frame 8 and a connecting plate 10. The seat of the wheelchair is fixed on the seat bottom plate 1, and the roller is arranged at the bottom of the chassis 7. The upper end of the rotating shaft 11 is fixed on the seat bottom plate 1, and the lower end is rotatably connected to the chassis 7 through a bearing. A positioning hole 16 is provided on the chassis 7. One end of the locking pin frame 8 is fixed on the rotating shaft 11, and the other end is fixed on the rotating shaft 11. A guide hole is provided, the lower end of the connecting plate 10 is hinged on the locking pin frame 8, and the upper end is hinged to one end of the handle 2; the guide pin 4 is hinged to the handle 2 and is arranged at a position adapted to the handle 2 and the positioning hole 16, and is slidably connected in the guide hole; the handle 2 is rotated to make the handle rotate downward around the hinge point with the connecting plate 10, the guide pin 4 slides downward along the guide hole, and the lower end can be inserted into the positioning hole 16, the seat bottom plate 1 is positioned on the chassis, the handle 2 is rotated upward, the guide pin 4 slides upward along the guide hole, and the lower end slides the positioning hole 16, and the seat bottom plate 1 can be rotated relative to the chassis through the rotating shaft.

[0034] Embodiment 2

[0035] like Figure 2 As shown, a rotating mechanism of a wheelchair of this embodiment has a structure that is basically the same as that of the first embodiment, except that an offset conical sleeve 3 is provided at the bottom of the seat bottom plate, and the angle between the axis of the conical hole of the conical sleeve 3 and the plane where the seat is located is 8°. The upper end of the rotating shaft 11 is provided with a conical surface that cooperates with the conical sleeve 3, and is fixed to the seat bottom plate 1 by taper cooperation with the conical sleeve 3. The rotating shaft 11 is vertically arranged, and the lower end is rotatably connected to the chassis 7 through a tapered roller bearing 6, so that the seat is tilted back by a small angle (8°), making the seat more comfortable. At the same time, the force on the conical sleeve 3 and the conical surface of the rotating shaft 11 are uneven when they contact, and rotating the seat can simultaneously drive the rotating shaft 11 to rotate. Figure 4 shown.

[0036] In this embodiment, the locking unit further includes a spring 5. Figure 6 , Figure 7 As shown, a detachable fixed sleeve at one end of the lock pin frame 8 is arranged on the rotating shaft 11, and a guide hole is arranged at the other end. Two connecting plates 10 are provided, and the lower ends of the two connecting plates 10 are respectively hinged on both sides of one end of the lock pin frame 8. The handle 2 is provided with two side ears 21 at one end close to the rotating shaft 11, and the two side ears are arranged on both sides of the rotating shaft 11. The upper ends of the two connecting plates 10 are respectively hinged with the two side ears 21 of the handle 2; Figure 5As shown, the guide pin 4 is slidably connected in the guide hole, the upper end of the guide pin 4 passes through the guide hole and is hinged to the middle of the handle 2, the lower end passes through the guide hole and is fixed with a spring retaining ring 12, the bottom of the lock pin frame 8 is provided with a groove 13 at the guide hole, the spring 5 is sleeved on the guide pin 4, and the upper end abuts in the groove at the bottom of the lock pin frame 8, and the lower end abuts on the spring retaining ring 12, the chassis 7 is provided with a positioning seat 14, the positioning seat 14 is provided with a positioning hole, and the lower end of the guide pin 4 is located in the positioning hole. Figure 3 As shown, the handle 2 is lifted upward at one end away from the rotating shaft, and the handle 2 drives the guide pin 4 to slide upward and compress the spring into the groove. The lower end of the guide pin 4 is separated from the positioning hole, and the rotating shaft 11 and the chassis 7 are unlocked. The rotating shaft 11 and the chassis 7 can rotate relative to each other, thereby driving the seat to rotate; release the handle, the spring 5 rebounds, and pushes the guide pin 4 to slide downward. The lower end of the guide pin 4 is inserted into the positioning hole, and the rotating shaft 11 and the chassis 7 are locked, and the seat cannot rotate.

[0037] Combination Figure 8 and 9 As shown, the lock pin frame 8 is provided with a connecting hole 81, which is located at the other end of the lock pin frame relative to the guide hole, and the direction of the line connecting the center of the connecting hole and the center of the guide hole is the length direction of the lock pin frame. A first screw hole 82 connected to the connecting hole is provided on one side or on both sides of the connecting hole 81, and the first screw hole 82 is located in the radial direction of the connecting hole perpendicular to the length direction of the lock pin frame; the rotating shaft 11 is provided with a connecting portion 86 adapted to the connecting hole, and a waist-shaped groove 84 arranged axially is provided at the radial position of the connecting portion 86 corresponding to the first screw hole 82, and a positioning shoulder 85 is provided at the lower end of the connecting portion 86. The connecting hole 81 of the lock pin frame 8 is sleeved on the connecting portion 86 of the rotating shaft 11 and axially positioned on the positioning shoulder 85. The screw is screwed into the first screw hole 82 and the end is tightly against the bottom surface of the waist-shaped groove 84, so that the lock pin frame 8 is fixed on the rotating shaft 11, and rotating the rotating shaft 11 can drive the lock pin frame 8 to rotate together.

[0038] Combination Figure 8 As shown, the lock pin frame 8 is also provided with a second screw hole 83, which is located in the axial direction of the same connection hole as the first screw hole 82, and the second screw hole 83 is located above the first screw hole 82; the lower end of the connecting plate 10 is provided with a through hole, and the screw passes through the through hole and is screwed into the second screw hole 83 to connect the connecting plate to the lock pin frame 8. If the second screw hole 83 is arranged below the first screw hole 82, the screw screwed into the first screw hole sinks into the countersunk hole corresponding to the first screw hole, providing space for the arrangement of the connecting plate 10.

[0039] In this embodiment, since both ends of the connecting plate 10 are hinged to the handle 2 and the lock pin frame 8 respectively, when the handle 2 is lifted, the upper end of the connecting plate 10 can rotate toward the side close to the guide pin 4, thereby ensuring that the guide pin 4 always moves in the vertical direction.

[0040] In this embodiment, there are two positioning seats 14, which are symmetrically arranged on the chassis 7 on both sides of the rotating shaft 11. The chassis 7 is fixed with an anti-rotation frame 9 on one side of the positioning seat 14. When the seat is rotated, the rotating shaft 11 drives the locking unit to rotate together. When one side of the lock pin frame 8 is against the anti-rotation frame 9, the lower end of the guide pin 4 is facing the positioning hole on the positioning seat 14. At this time, the handle 2 is released, and the lower end of the guide pin 4 can be inserted into the positioning hole under the action of the spring 5. The anti-rotation frame 9 can position the rotation of the rotating shaft 11, eliminating the trouble of aligning the positioning hole, and the operation is convenient and simple. Since the two positioning seats 14 are located on the same straight line with the rotating shaft, the rotation angle of the rotating shaft 11 is 180°, so that the wheelchair can be switched between front-wheel drive and rear-wheel drive.

[0041] Embodiment 3

[0042] Combination Fig.10 and Fig.11 As shown, the structure of this embodiment is basically the same as that of the first embodiment, except that in this embodiment, a vertical plate 15 extends upward from one side of the positioning seat 14, and when one side of the locking pin frame 8 is against the vertical plate 15, the lower end of the guide pin 4 is inserted into the positioning hole.

[0043] The technical solutions of the present invention are not limited to the above-mentioned embodiments, and any technical solutions obtained by equivalent replacement methods fall within the scope of protection required by the present invention.

Claims

1. A rotation positioning mechanism for a wheelchair, used for rotating a seat of the wheelchair relative to a chassis of the wheelchair, characterized in that: It includes a seat bottom plate, a rotating shaft, a chassis and a locking unit. The seat of the wheelchair is fixed on the seat bottom plate, the upper end of the rotating shaft is fixed on the seat bottom plate, and the lower end is rotatably connected to the chassis. The chassis is provided with a positioning hole. The locking unit includes a handle, a guide pin, a locking pin frame and a connecting plate. One end of the locking pin frame is fixed on the rotating shaft, and the other end is provided with a guide hole. The lower end of the connecting plate is hinged to the locking pin frame, and the upper end is hinged to one end of the handle. The guide pin is hinged to the handle and is arranged at a position where the handle and the positioning hole are adapted, and is slidably connected in the guide hole. The handle rotates downward around the hinge point with the connecting plate, and the lower end of the guide pin can be inserted into the positioning hole, and the seat bottom plate is positioned on the chassis. The seat bottom plate is provided with an offset cone sleeve, and the upper end of the rotating shaft is provided with a cone surface adapted to the taper of the cone sleeve. The seat bottom plate is pluggable and relatively non-rotatably connected to the upper end of the rotating shaft through the combination of the cone sleeve and the cone surface.

2. The rotation positioning mechanism of the wheelchair according to claim 1, characterized in that: The locking unit also includes a spring, which is sleeved on the guide pin, with the upper end of the spring abutting against the lock pin frame and the lower end abutting against the guide pin, and the elastic force of the spring causes the guide pin to extend downward.

3. The rotation positioning mechanism of the wheelchair according to claim 2, characterized in that: There are two positioning holes, and the two positioning holes are respectively arranged on a positioning seat, and the two positioning seats are symmetrically arranged on the chassis on both sides of the relative rotating shaft.

4. The rotation positioning mechanism of the wheelchair according to claim 3, characterized in that: The rotation positioning mechanism also includes an anti-rotation frame, which is fixed on the chassis and located at one side of the positioning seat. When the lock pin frame is against the anti-rotation frame, the lower end of the guide pin is inserted into the positioning hole.

5. The rotation positioning mechanism of the wheelchair according to claim 3, characterized in that: A vertical plate is extended upward from one side of the positioning seat. When one side of the locking pin frame is against the vertical plate, the lower end of the guide pin is inserted into the positioning hole.

6. The rotation positioning mechanism of a wheelchair according to claim 4 or 5, characterized in that: The bottom of the lock pin frame is provided with a groove at the guide hole, the lower end of the guide pin is connected with a spring retaining ring, the upper end of the spring abuts against the bottom surface of the groove, and the lower end abuts against the spring retaining ring.

7. The rotation positioning mechanism of a wheelchair according to claim 2, characterized in that: The lock pin frame is provided with a connecting hole, which is located at the other end of the lock pin frame relative to the guide hole, and the direction of the line connecting the center of the connecting hole and the center of the guide hole is the length direction of the lock pin frame. A first screw hole connected to the connecting hole is provided on one side or on both sides of the connecting hole, and the first screw hole is located in the radial direction of the connecting hole perpendicular to the length direction of the lock pin frame; the rotating shaft is provided with a connecting part adapted to the connecting hole, and an axially arranged waist-shaped groove is provided at the radial position of the connecting part corresponding to the first screw hole, and a positioning shoulder is provided at the lower end of the connecting part, the connecting hole of the lock pin frame is sleeved on the connecting part of the rotating shaft and axially positioned on the positioning shoulder, the screw is screwed into the first screw hole and the end is tightly against the bottom surface of the waist-shaped groove, so that the lock pin frame is fixed on the rotating shaft.

8. The rotation positioning mechanism of a wheelchair according to claim 7, characterized in that: The locking pin frame is also provided with a second screw hole, which is located in the same axial direction of the connecting hole as the first screw hole; a through hole is provided at the lower end of the connecting plate, and a screw passes through the through hole and is screwed into the second screw hole to connect the connecting plate to the locking pin frame; when the second screw hole is arranged below the first screw hole, the screw screwed into the first screw hole sinks into the countersunk hole corresponding to the first screw hole.

9. The rotation positioning mechanism of a wheelchair according to claim 7, characterized in that: The handle is provided with two side ears at one end close to the rotating shaft. The two side ears are symmetrically arranged on the two sides of the rotating shaft and are respectively hinged to a connecting plate.

10. The rotation positioning mechanism of a wheelchair according to claim 1, characterized in that: The lower end of the rotating shaft is rotatably connected to the chassis through a tapered roller bearing.

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