A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket.

Abstract

This utility model discloses a wheelchair structure capable of transforming from a circular wheel to a tracked sprocket. This transformation originates from the relative rotation between a fixed wheel and a moving wheel. The centers of the fixed wheel and the moving wheel are fixed by a circular shaft, allowing only relative rotation and no relative displacement. The fixed wheel panel has two longitudinal short grooves and two transverse long grooves arranged in a circular array, while the moving wheel panel has two corresponding arc-shaped short grooves and two arc-shaped long grooves. When the moving wheel rotates, the short and long grooves on the moving wheel maintain an angle of 90° to 100° with the short and long grooves on the fixed wheel. This wheelchair uses only two sets of hubs to achieve the effect of transforming from a circular wheel to a tracked sprocket. Compared with wheelchairs that simultaneously install circular wheels and tracked sprockets, this significantly reduces the weight of the wheelchair and lowers the manufacturing cost.

Description

Technical Field

[0001] This utility model relates to a novel wheelchair structure, and more particularly to a wheelchair structure that can transform from a circular wheel to a tracked sprocket. Background Technology

[0002] In today's era of rapid technological advancement, existing wheelchair structures are only suitable for movement on flat roads, and are difficult to maneuver effectively on sloping terrain or stairwells. If a wheelchair accidentally gets stuck in mud, it is often difficult to extricate itself and requires external assistance to get out of the predicament. In view of this, this utility model designs a novel tracked sprocket structure, which enables the wheelchair to move on rough ground or stairwells.

[0003] While similar wheelchairs using tracked sprockets already exist on the market, these wheelchairs require an additional pair of round wheels to ensure normal movement. This structure not only increases the wheelchair's weight but also raises production costs. In contrast, this invention only adds the weight of a few cylinders to the traditional wheelchair, effectively reducing costs compared to existing tracked sprocket wheelchairs on the market. Utility Model Content

[0004] This invention provides a wheelchair structure that can transform from a circular wheel to a tracked sprocket to solve the problem that existing wheelchairs cannot travel on uneven terrain.

[0005] To address the aforementioned shortcomings of existing wheelchairs, the technical solution adopted by this utility model is as follows: a wheelchair structure capable of transforming from a circular wheel to a tracked sprocket, comprising a wheelchair base, a wheelchair backrest, two sets of deformable wheel hubs, a pair of front wheels and footrest brackets, a front wheel linkage, a rear wheel and rear wheel bracket, a rear wheel linkage, a pair of wheelchair base brackets and two flat shafts horizontally mounted on the brackets, a pair of P-shaped plates and a central shaft, a left inner wheel drive shaft, a left pressure wheel, a left pressure wheel support frame and a left pressure wheel support shaft, a belt (or synchronous belt) for driving the left wheel to the central shaft, a right inner wheel drive shaft, a right pressure wheel, a right pressure wheel support frame and a right pressure wheel support shaft, a belt (or synchronous belt) for driving the right wheel to the central shaft, a belt (or synchronous belt) for driving the central shaft to a servo motor, two guide columns for the vertical movement of the central shaft, a circular shaft horizontally mounted on the two P-shaped plates, a cylinder for raising and lowering the central shaft, two pen-shaped cylinders for controlling the deformation of the wheel hubs, and gears and racks fixed on the pen-shaped cylinders, etc.

[0006] Furthermore, the deformable hub includes a tire, several chains, four inner wheels meshing with the chains, two Z-shaped support shafts fixing the upper and lower inner wheels, two H-shaped support shafts fixing the left and right inner wheels, a fixed wheel and a moving wheel, and four round wheel support frames on each of the front and rear sides.

[0007] Furthermore, the centers of the fixed wheel and the moving wheel are fixed by a circular shaft, allowing only relative rotation and no relative displacement. The fixed wheel panel has two short longitudinal grooves and two long transverse grooves at 90-degree angles, while the moving wheel panel has two corresponding short arc-shaped grooves and two long arc-shaped grooves. When the moving wheel rotates, the short and long arc-shaped grooves on the moving wheel maintain an angle of 90° to 100° with the short and long grooves on the fixed wheel. The Z-shaped support shaft and H-shaped support shaft are each fitted with a spacer at one end of the short and long grooves. When the fixed wheel and the moving wheel rotate relative to each other, the spacer moves up and down (or left and right) along the short (or long) groove under the push of the moving wheel, causing the Z-shaped support shaft (or H-shaped support shaft) to move up and down (or left and right).

[0008] Furthermore, the spacers in the short groove of the fixed wheel and the arc-shaped short groove of the moving wheel only rotate relative to each other, without relative movement. The rotation amplitude of the Z-shaped support shaft is controlled by the meshing of the broken gear and the arc-shaped rack on the moving wheel. The broken gear is fixed to the Z-shaped support shaft by a flat key, and there is neither relative rotation nor relative movement between the broken gear and the Z-shaped support shaft. The arc-shaped rack is welded to the moving wheel by a short shaft. In the circular wheel state, when the moving wheel rotates, the Z-shaped support shaft moves towards the center of the moving wheel. During this process, the arc-shaped rack on the moving wheel panel drives the broken gear on the Z-shaped support shaft to rotate counterclockwise, thereby causing the upper inner wheel (or lower inner wheel) at the other end of the Z-shaped support shaft to rotate to the same height as the left and right inner wheels.

[0009] Furthermore, the H-shaped support shaft of the left inner wheel moves within the long groove on the right side of the fixed wheel and the arc-shaped long groove on the right side of the moving wheel via a spacer. The H-shaped support shaft of the right inner wheel moves within the long groove on the left side of the fixed wheel and the arc-shaped long groove on the left side of the moving wheel via a spacer. The spacer and the H-shaped support shaft only rotate relative to each other, without relative movement. In order to keep the left and right H-shaped support shafts moving in a straight line, a bushing is provided on the left H-shaped support shaft so that it can move on the right H-shaped support shaft.

[0010] Furthermore, the relative rotation between the moving wheel and the fixed wheel is controlled by a pen-shaped cylinder. The outer edge of the moving wheel has teeth distributed on it. The cylinder body of the pen-shaped cylinder is fixedly connected to the rack, and the piston rod is fixed to the bottom of the wheelchair base through a floating joint. When the piston rod moves back and forth in a straight line, the cylinder body drives the rack connected to it to move synchronously. The rack drives the gear fixed to the wheelchair base to rotate, thereby causing the moving wheel to rotate. When the device is in the wheel form, the pen-shaped cylinder is in a retracted state; while in the tracked sprocket form, the cylinder is in an extended state.

[0011] Furthermore, the outer side of the hub is composed of sprockets, and the sprocket structure consists of eight circular wheel support frames on the front and rear sides. Several small wheels are densely distributed on the arc-shaped support edge of the circular wheel support frame. When the circular wheel support frame and the sprocket rotate, rolling friction occurs between the small wheels and the sprocket. One end of the short connecting rod of the circular wheel support frame is connected to the arc-shaped support edge, and the other end is fixed to the center position of the left inner wheel (or right inner wheel). One end of the long connecting rod is connected to the arc-shaped support edge, and the other end is fixed to the right H-shaped support shaft (or left H-shaped support shaft). When the H-shaped support shaft moves laterally, it causes the side length of the circular wheel support frame to change, thereby causing the entire circular wheel support frame to contract or expand. When the circular wheel support frame contracts, the outer contour of the hub deforms into a track-type sprocket; when the circular wheel support frame expands, the outer contour of the hub deforms into a circular wheel.

[0012] To secure the sprocket hubs on both sides to the wheelchair base, axle seats are installed on the fixed wheels of both wheelchair hubs and on the wheelchair base. The two axle seats on the wheelchair base are fixed to the axle seats of the left and right fixed wheels via rotating shafts. To ensure the wheelchair has steering function during movement, two flat shafts with teeth are added through the axle seats of the fixed wheels. A gear is installed in the middle area of ​​the flat shafts on both sides, so that it meshes with the teeth on the flat shafts on the left and right sides respectively. The rotation of the gear driven by the motor causes one flat shaft to move laterally to the left and the other to move laterally to the right, thereby causing the wheel hubs on both sides to turn. The gear and the servo motor shaft are driven by a belt (or synchronous belt).

[0013] To ensure the overall transmission effect of the wheelchair, the center of the left inner wheel and the center of the right inner wheel are driven by the left drive shaft and the right drive shaft respectively. The two drive shafts transmit the motor power through the intermediate shaft, and the motor and the intermediate shaft, as well as the intermediate shaft and the two drive shafts, are driven by belts or synchronous belts.

[0014] Furthermore, the belt or timing belt is equipped with rollers for clamping, and the clamping power comes from a spring fixed to the roller. One end of the spring is fixed to the roller, and the other end is fixed to the wheelchair base.

[0015] Furthermore, both ends of the central shaft are fixed within the through slots of the P-shaped plate. The intermediate shaft has through holes at both ends, allowing it to move up and down on guide posts. Springs are mounted on the guide posts, enabling the intermediate shaft to return to its original state when not under cylinder tension. A 30mm long circular tube is fitted onto the intermediate shaft, with its lower end fixed to a steel cable with screws. The other end of the steel cable is connected to the piston rod of the cylinder. The middle section of the steel cable passes over a fixed pulley, generating rolling friction with it. The central shaft of the fixed pulley is fixed to the P-shaped plates at both ends. When the hub is in the circular wheel state, the cylinder piston rod extends, and the intermediate shaft is returned to the highest point of the through slot in the P-shaped plate by the springs on both sides. When the hub is in the track sprocket state, the cylinder piston rod retracts, and the intermediate shaft is pulled to the lowest point by the steel cable.

[0016] Furthermore, the belt tension between the intermediate shaft and the motor is also controlled by two rollers, one above the other. The central shafts of the two rollers are fixed in the through slots of the O-shaped plate. Both central shafts have through holes, and a guide post is installed in the through holes. The upper end of the guide post is fixed to the wheelchair base. Springs are provided between the uppermost end of the guide post and the central shaft of the upper roller, and between the central shaft of the upper roller and the central shaft of the lower roller, to adjust the tension.

[0017] Compared with the prior art, this utility model provides a wheel hub that can transform from a spherical wheel to a tracked sprocket, which has the following beneficial effects:

[0018] This wheelchair uses only two sets of hubs to transform from round wheels to tracked sprockets, significantly reducing its weight and manufacturing cost compared to wheelchairs that use both round wheels and tracked sprockets. Furthermore, when the wheelchair hubs are tracked, the left and right inner wheels can move up and down within a certain range, allowing for easy ascent and descent on bumpy surfaces. With round wheels, the user can move quickly on flat roads; with tracked wheels, the user lies on the tracked wheels, shifting their center of gravity backward, ensuring safety while traversing uneven terrain as if on flat ground. Attached Figure Description

[0019] Figure 1 This is an overall view of the wheelchair of this utility model when the wheel hub is a round wheel.

[0020] Figure 2 This is an overall view of the wheelchair of this utility model when the wheelchair hub is a tracked sprocket, where 1-wheel hub.

[0021] Figure 3 This is a schematic diagram of the wheelchair hub structure of this utility model, wherein: 101-tire; 102-sprocket; 103-left inner wheel; 104-right inner wheel; 105-upper inner wheel; 106-lower inner wheel; 107-upper Z-shaped support shaft; 108-lower Z-shaped support shaft; 109-left H-shaped support shaft; 110-right H-shaped support shaft; 111-fixed wheel; 112-moving wheel; 113-round wheel support frame; 114-short connecting rod; 115-long connecting rod.

[0022] Figure 4 This is a diagram of the fixed structure of the moving wheel and the back gear of this utility model, wherein 111-fixed wheel; 112-moving wheel; 116-arc-shaped rack; 117-arc-shaped rack.

[0023] Figure 5This is a diagram showing the state of the Z-type support shaft and the H-type support shaft when the wheelchair hub of this utility model is a round wheel, wherein 107-upper Z-type support shaft; 108-lower Z-type support shaft; 109-left H-type support shaft; 110-right H-type support shaft; 111-fixed wheel; 112-moving wheel.

[0024] Figure 6 This is a diagram showing the state of the Z-type support shaft and H-type support shaft when the wheelchair hub of this utility model is a tracked sprocket. In the diagram, 107 is the upper Z-type support shaft; 108 is the lower Z-type support shaft; 109 is the left H-type support shaft; 110 is the right H-type support shaft; 111 is the fixed wheel; and 112 is the moving wheel.

[0025] Figure 7 This is an exploded view of the structure of four inner wheels, a moving wheel, and a fixed wheel. Among them, 107-Z-shaped support shaft of the upper inner wheel; 1071-shaft sleeve; 121-broken gear; 1072-spacer sleeve; 1073-shaft sleeve; 1074-spacer sleeve; 1075-locking nut; 108 - Z-type support shaft for the lower inner wheel; 122 - Broken gear; 1081 - Bushing; 1082 - Spacer; 1083 - Bushing; 1084 - Spacer; 1085 - Locking nut; 109-H-type support shaft for the left inner wheel; 1091-Shaft sleeve; 1092-Spacer sleeve; 1093-Shaft sleeve; 1094-Spacer sleeve; 1095-Locking nut; 110 - H-type support shaft of the right inner wheel; 1101 - Bushing; 1102 - Spacer; 1103 - Bushing; 1104 - Spacer; 1105 - Locking nut.

[0026] Figure 8 This is an exploded view of the left inner wheel and the short connecting rod of the support frame. 201 - Left drive shaft; 1031 - Left rear end cover; 109 - H-shaped support shaft of the left inner wheel; 103 - Left inner wheel; 1032 - Bearing; 1141 - Short connecting rod; 1033 - Spacer; 1142 - Short connecting rod; 1034 - Left front end cover; 1035 - Shaft end cover.

[0027] Figure 9 This is a front view of the left inner wheel of the wheelchair after assembly.

[0028] Figure 10 This is a schematic diagram of the sprocket flange and support frame, where 1021 is the chain; 102 is the sprocket; and 113 is the support frame.

[0029] Figure 11This is a diagram showing the positions of the transmission components in the wheelchair's wheelchair configuration. 201 - Left drive shaft; 2011 - Pulley; 202 - Two connecting rods; 203 - Long shaft; 204 - Foot support bracket; 2041 - Short shaft extending from the wheelchair base bracket; 205 - Wheelchair base; 206 - Wheelchair armrest; 208 - Wheelchair backrest; 301 - Right drive shaft; 3011 - Pulley; 302 - Support frame for the rear small wheel; 303 - Connecting rod; 401 - Intermediate shaft; 4011 - Pulley driving the left drive shaft; 4012 - Pulley driving the motor; 4013 - Pulley driving the right drive shaft.

[0030] Figure 12 This is a schematic diagram of the left drive shaft and the intermediate shaft drive belt (or synchronous belt) in the wheelchair's round wheel state of this utility model. In the diagram, 201-left drive shaft; 207-two left-side pressure rollers; 2071-short shaft at the center of the two left-side pressure rollers; 2072-left-side pressure rod; 2073-two left-side springs; 401-intermediate shaft; 402-left drive shaft and intermediate shaft drive belt (or synchronous belt); 405-front P-shaped plate; 4051-long shaft fixed to the front P-shaped plate.

[0031] Figure 13 This is a diagram showing the positions of various transmission components in the tracked sprocket configuration of this utility model wheelchair. Components include: 5 - wheelchair base; 207 - two left-side pressure rollers; 2071 - short shaft at the center of the two left-side pressure rollers; 2072 - left-side pressure rod; 2073 - two left-side springs; 304 - fixing bracket on the wheelchair base; 305 - two right-side pressure rollers; 3051 - short shaft at the center of the two right-side pressure rollers; 3052 - right-side pressure rod; 3053 - two right-side springs; 402 - left-side drive shaft and intermediate shaft drive belt (or synchronous belt); 403 - intermediate shaft and motor drive belt (or synchronous belt); 404 - right-side drive shaft and intermediate shaft drive belt (or synchronous belt); 405 - front P-shaped plate; 4051 - long shaft fixed to the front P-shaped plate; 406 - rear P-shaped plate; 4061 - long shaft fixed to the rear P-shaped plate.

[0032] Figure 14 This is a schematic diagram of the left drive shaft and the intermediate shaft drive belt (or synchronous belt) in the tracked sprocket configuration of this utility model wheelchair. In the diagram, 201 is the left drive shaft; 207 are the two left-side pressure rollers; 2071 is the short shaft at the center of the two left-side pressure rollers; 2072 is the left-side pressure rod; 2073 is the two left-side springs; 401 is the intermediate shaft; 402 is the left drive shaft and the intermediate shaft drive belt (or synchronous belt); 405 is the front P-shaped plate; and 4051 is the long shaft fixed to the front P-shaped plate.

[0033] Figure 15This is a schematic diagram of the transmission principle between the motor and the intermediate shaft in the tracked sprocket configuration of this utility model wheelchair. 401 - intermediate shaft; 4012 - pulley driving the motor shaft; 403 - transmission belt (or synchronous belt) between the intermediate shaft and the motor; 407 - pulley on the motor shaft; 4071 - guide shaft; 4072 - two intermediate pressure rollers; 4073 - short shaft passing through the two pressure rollers; 4074 - O-shaped plate.

[0034] Figure 16 This is a schematic diagram of an O-ring, where 4071 is the guide shaft; 4072 is the two middle clamping rollers; 4073 is the short shaft passing through the two clamping rollers; and 4074 is the O-ring.

[0035] Figure 17 This is a cross-sectional view of the intermediate shaft, where: 401 - intermediate shaft; 4011 - pulley driving the left drive shaft; 4012 - pulley driving the motor; 4013 - pulley driving the right drive shaft; 4014 - bearing between the bushing on the P-type plate and the intermediate shaft; 4015 - inner shaft of the intermediate shaft; 4016 - bearing between the inner shaft and the intermediate shaft; 405 - front P-type plate; 4052 - guide shaft fixed on the front P-type plate; 4053 - bushing on the P-type plate; 406 - rear P-type plate; 4062 - guide shaft fixed on the rear P-type plate; 408 - round tube; 4081 - wire rope; 4082 - cylinder; 4083 - fixed pulley on the long shaft; 4084 - long shaft fixed between the two P-type plates.

[0036] Figure 18 This is a schematic diagram of the transmission principle of a pen-shaped cylinder and a driving wheel. In the diagram, 112-driving wheel; 1121-pen-shaped cylinder body; 1122-rack fixed to the pen-shaped cylinder body; 1123-gear; 1124-short shaft and short shaft support; 1125-piston rod; 1126-floating joint.

[0037] Figure 19 This is a schematic diagram of the steering principle of the wheelchair of this utility model, wherein 601-flat shaft bracket; 602-flat shaft with gear teeth; 603-gear in the middle of the flat shaft; 604-pinion; 605-servo motor; 606-belt (or synchronous belt).

[0038] Figure 20 This is a bottom view of the wheelchair base of this utility model in its round wheel configuration.

[0039] Figure 21 This is a bottom view of the wheelchair base with the track sprocket in the present invention. Detailed Implementation

[0040] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0041] This utility model provides a novel wheelchair structure that can transform from a circular wheel to a tracked sprocket. The structure includes: a wheelchair base 5, a wheelchair backrest 208, two sets of deformable wheel hubs 1, a pair of front wheels and footrest supports 204, a rear wheel and rear wheel support 302, a wheelchair base support 5, two flat shafts 602 horizontally mounted on the support, a central shaft 401, a left drive shaft 201, a left pressure wheel 207, a long shaft 4051 extending from the front P-shaped plate 405, and a left pressure rod 2072, a belt (or synchronous belt) 402 for driving the left drive shaft 201 and the central shaft, a right drive shaft 301, and a right pressure wheel 307. 05. The long shaft 4061 extending from the rear P-type plate 406 and the right pressure rod 3052, the belt (or synchronous belt) 404 for the transmission between the right drive shaft and the intermediate shaft, the two guide shafts 4052 and 4062 for the up and down movement of the intermediate shaft, the round shaft 4084 lying between the two P-type plates, the cylinder 4082 for lifting the intermediate shaft, the belt (or synchronous belt) 403 for the transmission between the intermediate shaft 401 and the servo motor, the O-type plate 4074 for controlling the tension of the belt (or synchronous belt) 403, the two pen-shaped cylinders 1121 for controlling the deformation of the hub, and the rack 1122 fixed on the pen-shaped cylinder, etc.

[0042] This utility model provides a novel wheelchair structure that can transform from a circular wheel to a tracked sprocket. Its working principle is as follows: the mutual rotation of the moving wheel and the stationary wheel enables the wheel hub to transform from a circular wheel to a tracked sprocket. Please refer to [link to relevant documentation]. Figure 18 First, the pen-shaped cylinder 1121 moves, causing the rack 1122 to drive the gear 1123 and the moving wheel 112 to rotate. The fixed wheel 111 is fixed below the wheelchair base. The moving wheel 112 and the fixed wheel 111 generate relative rotational motion, driving the shaft ends of the upper and lower Z-shaped support shafts 107 and 108 and the left and right H-shaped support shafts towards the center of the fixed wheel. As the upper and lower Z-shaped support shafts 107 and 108 move towards the center of the fixed wheel, the broken gears 116 and 117 simultaneously rotate counterclockwise under the guidance of the arc-shaped rack until they reach the same height. Please refer to [link / reference]. Figure 5 and Figure 6At the same time, the left drive shaft 201 and the right drive shaft 301 move to the front and rear sides of the wheelchair respectively, the piston rod of the cylinder 4082 retracts, driving the steel cable 4081 to move, pulling down the intermediate shaft 401 to adapt to the length of the belt (or synchronous belt), and the front wheel and foot support bracket 204 and the rear wheel and rear wheel support bracket 302 also move to the front and rear sides respectively under the drive of the front and rear drive shafts.

[0043] Please see Figure 3 The deformable wheel hub includes a tire 101, a sprocket 102, a left inner wheel 103, a right inner wheel 104, an upper inner wheel 105, and a lower inner wheel 106 that mesh with a chain, a Z-shaped support shaft 107 that fixes the upper inner wheel and a Z-shaped support shaft 108 that fixes the lower inner wheel, an H-shaped support shaft 109 that fixes the left inner wheel and an H-shaped support shaft 110 that fixes the right inner wheel, a fixed wheel 111 and a moving wheel 112, four round wheel support frames 113 on each of the front and rear sides, and short connecting rods 114 and long connecting rods 115, etc.

[0044] Please see Figure 4 and Figure 7 First, the arc-shaped racks 116 and 117 are welded and fixed to the moving wheel 112 via a short shaft, so that the two arc-shaped short grooves on the moving wheel 112 are concentric with the arc-shaped racks 116 and 117 respectively. Then, the fixed wheel 111 and the moving wheel 112 are both fixed to the same short shaft 120. The moving wheel 112 is welded to the short shaft 120, while the fixed wheel 111 is fixed to the short shaft 120 via a bushing 121. The bushing 121 and the short shaft 120 can rotate relative to each other. The two short grooves on the fixed wheel 111... The long groove and the two short grooves are each equipped with sliding sleeves 1094, 1104, 1074, and 1084. The two arc-shaped long grooves and the two arc-shaped short grooves of the moving wheel are also equipped with sliding sleeves 1072, 1082, 1092, and 1102. The distances from the farthest and nearest ends of the two long grooves of the fixed wheel and the two arc-shaped long grooves of the moving wheel to the center of the short shaft are the same. The distances from the farthest and nearest ends of the two short grooves of the fixed wheel and the two arc-shaped short grooves of the moving wheel to the center of the short shaft are also the same.

[0045] Please see Figure 7The Z-shaped support shaft 107, fixed to the upper inner wheel, passes through the bushing 1071 and is fixedly connected to the broken gear 121 by means of a flat key. It is then fixed to the spacer 1072 in the short groove on the upper side of the moving wheel. Next, it passes through the bushing 1073 through the spacer 1074 in the arc-shaped short groove on the upper side of the fixed wheel to complete the fixation. Finally, the shaft end of the Z-shaped support shaft is fixed with a lock nut 1075. Similarly, the Z-shaped support shaft 108, fixed to the lower inner wheel, is fixedly connected to the broken gear 122 by a flat key. It then passes through the bushing 1081 and is fixed to the spacer 1082 in the short groove on the lower side of the moving wheel. Next, it passes through the bushing 1083 through the spacer 1084 in the arc-shaped short groove on the lower side of the fixed wheel to complete the fixation. Finally, the shaft end of the Z-shaped support shaft is fixed with a lock nut 1085. The distance between the broken gear 121 and the broken gear 122 and the moving wheel differs by more than 1 mm.

[0046] Furthermore, the H-shaped support shaft 109, which is fixed to both ends of the left inner wheel by bearings, passes through the bushing 1091 and is fixed to the spacer 1092 in the long groove on the right side of the moving wheel. Then, it passes through the bushing 1093 and the spacer 1094 in the long groove on the right side of the fixed wheel. Finally, the shaft end of the H-shaped support shaft is fixed with the lock nut 1095. Similarly, the H-shaped support shaft 110, which is fixed to both ends of the right inner wheel by bearings, passes through the bushing 1101 and is fixed to the spacer 1102 in the long groove on the left side of the moving wheel. Then, it passes through the bushing 1103 and the spacer 1104 in the long groove on the left side of the fixed wheel. Finally, the shaft end of the H-shaped support shaft is fixed with the lock nut 1105.

[0047] This utility model provides a novel wheelchair structure, including a transmission method for the wheelchair structure that enables the transformation of the circular wheelchair into a tracked sprocket:

[0048] refer to Figure 8 and Figure 9 The left drive shaft 201 is axially fixed to the left rear end cover 1031, the left H-shaped support shaft 109, the left inner wheel 103, the bearing 1032, the short connecting rod 1141, the spacer 1033, the short connecting rod 1142, and the left front end cover 1034 via bearings. The left drive shaft 201 and the left inner wheel 103 are radially fixed by a flat key. The left front end cover 1034 is fixed to the H-shaped support shaft 109 by screws passing through the spacer 1033. After assembly, screws pass through the shaft end cover 1035 to fix it to the shaft end of the left drive shaft 201. The right drive shaft 301 is similar.

[0049] refer to Figure 3 and Figure 8The short connecting rods 114 of the left front and rear support frames are respectively fixed to the corresponding left front end cover 1034 and left rear end cover 1031; there is no relative rotation or relative movement between the short connecting rods 114 of the left support frame and the left front end cover 1034, the left rear end cover 1031, and the left H-shaped support shaft 109. One end of the long connecting rod 115 of the left support frame is fixed to the support frame 113, and the other end is fixed to the shaft end of the right H-shaped support shaft 110. The long connecting rod 115 of the left support frame can rotate relative to the support frame 113 and the right H-shaped support shaft 110. The implementation method of the right support frame is similar.

[0050] refer to Figure 10 To drive the sprocket 102, the edges of the left inner wheel 103, right inner wheel 104, upper inner wheel 105, and lower inner wheel 106 are all toothed. At the same time, in order to keep the chain round when the hub is transformed into a round wheel, the outer edge of the chain 1021 is provided with a folded edge, and the outer edge of the support shaft 113 supporting the chain is provided with several small wheels. The diameter of the small wheels is larger than the maximum gap between two adjacent chain folded edges, so that the support frame 113 can fully support the outline of the round wheel.

[0051] refer to Figure 11 Two connecting rods 202 are connected to the left drive shaft 201. The two connecting rods 202 are connected to the two front wheels and the long shaft 203 of the foot support bracket 204. The middle section of the foot support bracket 204 rotates around the short shaft 2041 extending from the left end of the base bracket 205. The uppermost end of the foot support bracket 204 is connected to the wheelchair armrest 206. The other end of the wheelchair armrest 206 is connected to the wheelchair backrest 208. The right drive shaft 301 is connected to the support frame 302 of the rear small wheel. The other end of the support frame 302 is connected to the connecting rod 303. The other end of the connecting rod 303 is fixed to the fixing frame 304 of the wheelchair base. The connecting rod 303 can rotate around this center.

[0052] refer to Figure 11 , Figure 12 , Figure 13 and Figure 14The left drive shaft 201 and the right drive shaft 301 are equipped with pulleys 2011 and 3013, respectively, which are connected to the pulleys 4011 and 4013 on the intermediate shaft 401 via belts (or timing belts) 402 and 404, respectively. The left belt (or timing belt) 402 has two pressure rollers 207 on its upper and lower sides, and the right belt (or timing belt) 404 has two pressure rollers 305 on its upper and lower sides. Each pressure roller has a short shaft running through it. The two short shafts 2071 of the left pressure roller 207 are fixed to the left pressure rod 2072 by locking nuts, and the two short shafts 3051 of the right pressure roller 305 are fixed by locking nuts. The two short shafts 2071 on the left side are fixed to the right pressure rod 3052; two springs 2073 are connected to one side of the two short shafts 2071 on the left side, and the other side of the two springs 2073 is fixed to the wheelchair base 5. The other end of the left pressure rod 2072 is fixed to the long shaft 4051 extending from the P-shaped plate 405. The pressure rod 2072 and the long shaft 4051 can only rotate relative to each other and cannot move relative to each other. Two springs 3053 are connected to one side of the two short shafts 3051 on the right side, and the other side of the two springs 3053 is fixed to the wheelchair base 5. The other end of the right pressure rod 3052 is fixed to the long shaft 4061 extending from the P-shaped plate 406. The pressure rod 3052 and the long shaft 4061 can only rotate relative to each other and cannot move relative to each other.

[0053] refer to Figure 15 and Figure 16 The pulley 4012 on the intermediate shaft 401 is connected to the pulley 407 on the motor shaft by a belt (or synchronous belt) 403. The belt (or synchronous belt) 403 is also tensioned by two pressure rollers 4072. Two short shafts 4073 pass through the two pressure rollers 4072. The pressure rollers are fixed on both sides of the short shafts 4073 with lock nuts. The other end of the two short shafts is fixed on the O-plate 4074. Two through holes are made on the side of the short shafts 4073 near the O-plate 4074. The guide shaft 4071 passes through the two short shafts 4073 and is fixed on the wheelchair base. Springs are placed between the short shafts 4073 on the guide shaft 4071 and between the short shafts 4073 and the wheelchair base 5. Finally, the guide shaft 4071 is fixed with lock nuts.

[0054] refer to Figure 17The intermediate shaft 401 has two outer bearings 4014 on its outer side, which contact the bushings 4053 of the P-type plates 405 and 406. The intermediate shaft 401 has two inner bearings 4016 on its inner side, which contact the inner shaft 4015. The inner shaft 4015 has two through holes on both sides. One end of the guide shaft 4052 and guide shaft 4062 are fixed to the P-type plates 405 and 406 respectively, and the other end passes through the inner shaft 4015. Through holes on both sides; when the wheelchair is working, the intermediate shaft undertakes the transmission function, and the inner shaft of the intermediate shaft undertakes the function of fixing the position of the intermediate shaft; in addition to three pulleys, the intermediate shaft 401 has a 30mm long round tube 408 fitted on it. The upper part of the round tube 408 is fixed to the wire rope 4081 with screws. The other end of the wire rope 4081 is connected to the piston rod of the cylinder 4082. The middle section of the wire rope passes around the fixed pulley 4083, and the long shaft 4084 is fixed to the P-shaped plates on both sides through the center of the fixed pulley.

[0055] refer to Figure 14 The rotation of the drive wheel 112 is controlled by the pen-shaped cylinder 1121 driving the rack 1122. The outer edge of the drive wheel has teeth. In order to change the direction of movement of the drive wheel, a gear 1123 is added between the drive wheel teeth and the rack of the pen-shaped cylinder. The gear is fixed to the wheelchair base 5 by a short shaft and a short shaft bracket 1124. The gear 1123 and the short shaft 1124 can rotate relative to each other. The cylinder body of the pen-shaped cylinder 1121 is fixedly connected to the rack 1122, and the piston rod 1125 of the pen-shaped cylinder is fixed to the wheelchair base 5 after being connected to the floating joint 1126.

[0056] This utility model also includes wheelchair steering control, the implementation method of which is as follows: (See reference) Figure 19 Two flat shaft brackets 601 are installed at each of the fixed wheels 111 on both sides of the wheelchair. Then, two flat shafts 602 are installed on the flat shaft brackets 601 respectively. The flat shafts 602 can rotate on the flat shaft brackets 601. Both flat shafts 602 have gear teeth. A gear 603 is set in the middle of the two flat shafts 602, so that it meshes with the gear teeth on the left and right flat shafts respectively. The rotation of the gear causes the two flat shafts to produce relative displacement, so as to realize the steering of the wheelchair. There is a small gear 604 below the gear 603. The small gear 604 and the servo motor 605 are driven by a belt (or synchronous belt) 606.

[0057] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket, characterized in that, This deformation behavior originates from the relative rotation between the fixed wheel and the moving wheel; the centers of the fixed wheel and the moving wheel are fixed by a circular shaft, and the two can only rotate relative to each other, but cannot produce relative displacement; the fixed wheel panel has two longitudinal short grooves and two transverse long grooves distributed in a circular array, and the moving wheel panel has two corresponding arc-shaped short grooves and two arc-shaped long grooves; when the moving wheel rotates, the short grooves and long grooves on the moving wheel maintain an angle of 90° to 100° with the short grooves and long grooves on the fixed wheel respectively.

2. The wheelchair structure according to claim 1, which can transform from a circular wheel to a tracked sprocket, is characterized in that, The device includes a hub with four inner wheels forming a frame. The outer edges of the four inner wheels are evenly distributed with teeth to facilitate transmission with an outer sprocket. Both the upper and lower inner wheels are equipped with Z-shaped support shafts. One end of the Z-shaped support shaft is fixed to the center of the inner wheel and can rotate relative to it. The other end is fixed in a short groove of the fixed wheel and a short groove of the moving wheel. When the moving wheel rotates relative to the fixed wheel, the Z-shaped support shaft slides upwards or downwards within the short groove. Both the left and right inner wheels are equipped with H-shaped support shafts. One end of the H-shaped support shaft is fixed to the center of the inner wheel and can rotate relative to it. The other end is fixed in a long groove of the fixed wheel and a long groove of the moving wheel. When the moving wheel rotates relative to the fixed wheel, the H-shaped support shaft moves laterally within the long groove.

3. The wheelchair structure according to claim 2, which can transform from a circular wheel to a tracked sprocket, is characterized in that, The spacer sleeves in the short grooves of the fixed wheel and the arc-shaped short grooves of the moving wheel only rotate relative to the Z-shaped support shaft, without relative movement. The rotation amplitude of the Z-shaped support shaft is controlled by the meshing of the broken gear and the arc-shaped rack on the moving wheel. The broken gear is fixed to the Z-shaped support shaft by a flat key, and there is neither relative rotation nor relative movement between the broken gear and the Z-shaped support shaft. The arc-shaped rack is welded to the moving wheel by a short shaft. In the circular wheel state, when the moving wheel rotates, the Z-shaped support shaft moves towards the center of the moving wheel. During this process, the arc-shaped rack on the moving wheel panel drives the broken gear on the Z-shaped support shaft to rotate counterclockwise, thereby causing the upper or lower inner wheel at the other end of the Z-shaped support shaft to rotate to the same height as the left and right inner wheels.

4. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 2, characterized in that, The H-shaped support shaft of the left inner wheel moves within the long groove on the right side of the fixed wheel and the arc-shaped long groove on the right side of the moving wheel via a spacer. The H-shaped support shaft of the right inner wheel moves within the long groove on the left side of the fixed wheel and the arc-shaped long groove on the left side of the moving wheel via a spacer. The spacer and the H-shaped support shaft only rotate relative to each other, but do not move relative to each other. In order to keep the left and right H-shaped support shafts moving in a straight line, a bushing is provided on the left H-shaped support shaft so that it can move on the right H-shaped support shaft.

5. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 2, characterized in that, The relative rotation between the moving wheel and the fixed wheel is controlled by a pen-shaped cylinder. The outer edge of the moving wheel has teeth. The cylinder body of the pen-shaped cylinder is fixedly connected to the rack, and the piston rod is fixed to the bottom of the wheelchair base through a floating joint. When the piston rod moves back and forth in a straight line, the cylinder body drives the rack fixed to it to move synchronously on the guide rail. The rack drives the gear fixed to the wheelchair base to rotate, thereby causing the moving wheel to rotate. When the wheel hub is in the round wheel form, the pen-shaped cylinder is in the retracted state; while in the tracked sprocket form, the cylinder is in the extended state.

6. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 2, characterized in that, The outer side of the hub is composed of sprockets, and the sprocket structure consists of eight circular wheel support frames on the front and rear sides. Several small wheels are densely distributed on the arc-shaped support edges of the circular wheel support frames. When the circular wheel support frames and sprockets rotate, rolling friction occurs between the small wheels and the sprockets. One end of the short connecting rod of the circular wheel support frame is connected to the arc-shaped support edge, and the other end is fixed to the center position of the left or right inner wheel. One end of the long connecting rod is connected to the arc-shaped support edge, and the other end is fixed to the right or left H-shaped support shaft. When the H-shaped support shaft moves laterally, it causes the side length of the circular wheel support frame to change, thus causing the entire circular wheel support frame to contract or expand. When the circular wheel support frame contracts, the outer contour of the hub deforms into a track-type sprocket; when the circular wheel support frame expands, the outer contour of the hub deforms into a circular wheel.

7. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 2, characterized in that, The two wheel hubs are fixed to the fixed wheels with screws, and the fixed wheels are then fixed to the wheelchair base with a rotating shaft. To ensure that the wheelchair has a steering function during movement, two flat shafts with teeth are added to the fixed wheel axle. A gear is placed in the middle of the two flat shafts, so that it meshes with the teeth on the left and right flat shafts respectively. The motor drives the gear to rotate, causing the two flat shafts to move laterally in opposite directions, thereby turning the two wheel hubs.

8. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 2, characterized in that, The center of the left inner wheel and the center of the right inner wheel are driven by the left drive shaft and the right drive shaft respectively. The two drive shafts transmit motor power through the intermediate shaft. The motor and the intermediate shaft, and the intermediate shaft and the two drive shafts are driven by belts or synchronous belts. The belts or synchronous belts are equipped with rollers for pressing. The pressing power comes from the springs fixed to the rollers, and the other end of the springs is fixed to the wheelchair base.

9. A wheelchair structure capable of transforming from a circular wheel to a tracked sprocket according to claim 8, characterized in that, Both ends of the intermediate shaft are fixed in the grooves that run through the front and back of the P-shaped plate. The intermediate shaft has through holes at both ends, allowing it to move up and down on the guide posts at both ends. Springs are installed on the guide posts, so that the intermediate shaft can return to its original state when it is not subjected to cylinder tension.

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