wheelchair

Abstract

To improve a riding feeling by preventing an operation part of a folding mechanism from coming into contact with a seated wheelchair user in a wheelchair equipped with the folding mechanism.SOLUTION: A folding mechanism 70 includes an operation part 74 for changing one of a folded state and a developed state to the other of a left side support arm and a right side support arm. The operation part 74 is arranged with a predetermined space below an upper end part of a sheet frame 7.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present invention relates to a foldable wheelchair that is configured to be foldable. [Background technology]

[0002] Conventionally, folding wheelchairs that are configured to be foldable when not in use have been known (see, for example, Patent Document 1). The wheelchair in Patent Document 1 includes left and right side frames on which the drive wheels are pivoted, and a support arm and a cross member that connect the left and right side frames. When in use, the support arm and cross member are swung in a direction that widens the distance between the left and right side frames to keep the wheelchair in an unfolded state, while when not in use, the arm supports of the left and right side frames are held, and a force is applied in a direction that narrows the distance between the left and right side frames to swing the support arm and cross member to keep the wheelchair in a folded state. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-198334 A Summary of the Invention [Problem to be solved by the invention]

[0004] Foldable wheelchairs, such as the wheelchair of Patent Document 1, can be folded up when not in use to make it compact, thereby requiring less space for storage, and so foldable wheelchairs have become widespread.

[0005] On the other hand, for example, when folding the wheelchair of Patent Document 1, the wheelchair user needs to hold the arm supports of the left and right side frames and operate them in a direction to narrow the distance between the left and right side frames, but some wheelchair users may find it difficult to perform such a folding operation by themselves. Also, when folding a wheelchair, there is a method of pulling it by holding the drive wheels other than the side frames, but this method may also be difficult for some wheelchair users. If the wheelchair user cannot fold the wheelchair by themselves, they need help, such as being supported by people around them.

[0006] In addition, wheelchair users who can drive a car may drive the car alone to increase their freedom of movement. In this case, after transferring from the wheelchair to the driver's seat of the car, the wheelchair user must reach out to the wheelchair outside the car and fold the wheelchair in a state where their body is difficult to move. This makes the folding operation, which involves pulling the wheelchair by holding part of the wheelchair body or the drive wheels, even more difficult, and the folding operation is a burden for the wheelchair user. The same applies when a wheelchair user rides in the passenger seat of a car.

[0007] To address the above-mentioned issues, it is conceivable to provide a folding operation unit so that the folding operation can be performed with one hand, for example. It would be preferable to place this operation unit between the pair of side frames, as this would provide a good balance, but since a wheelchair user will be seated between the pair of side frames, simply providing the operation unit would come into contact with the wheelchair user, raising concerns that the ride comfort would be adversely affected.

[0008] The present invention has been made in consideration of these points, and its object is to improve the riding comfort of a wheelchair equipped with a folding mechanism by preventing the operating part of the folding mechanism from causing an uncomfortable feeling to a seated wheelchair user. [Means for solving the problem]

[0009] In order to achieve the above object, a first aspect of the present disclosure can be premised on a foldable wheelchair on which a wheelchair user can sit. The wheelchair includes a left side frame that supports a drive wheel on the left side of the vehicle body, a right side frame that supports a drive wheel on the right side of the vehicle body, a left support arm that is rotatably connected to the left side frame, a right support arm that is rotatably connected to the right side frame, a folding mechanism that foldably connects the left support arm and the right support arm in the left-right direction of the vehicle body, and a seat frame that has a seating frame that supports a seat cushion part on which a wheelchair user sits. The folding mechanism has an operating unit for changing the left support arm and the right support arm from one of a folded state and an unfolded state to the other. The operating unit is spaced downward from an upper end of the seating frame by a predetermined distance or more in a side view.

[0010] With this configuration, the left support arm and the right support arm can be easily changed from the unfolded state to the folded state, and conversely from the folded state to the unfolded state, by operating the operating part, making it possible, for example, to fold the wheelchair to make it compact or unfold the wheelchair to a seatable state while remaining seated in the driver's seat or passenger seat of a car.

[0011] When a wheelchair user sits on the seat cushion in the unfolded state, the operation unit is disposed at a predetermined distance or more below the upper end of the seat frame supporting the seat cushion in a side view, so that the operation unit does not come into contact with the seat cushion. As a result, the operation unit does not come into contact with the parts of the seat cushion that correspond to the legs and buttocks of the wheelchair user, so the wheelchair user does not feel uncomfortable and the ride is comfortable.

[0012] In addition, the seat cushion part may be deformed so as to sink when a wheelchair user sits on it, and the amount of sinking increases as the wheelchair user's weight increases. However, since the operating part is disposed at a distance lower than a predetermined distance from the upper end of the seat frame as viewed from the side, even if the seat cushion part sinks when a heavy wheelchair user sits on it, the seat cushion part is prevented from contacting the operating part. In other words, the predetermined distance is a size that can prevent contact between the seat cushion part and the operating part even if the maximum load assumed by the wheelchair acts on the seat cushion part. The maximum load assumed by the wheelchair can be set arbitrarily, but is, for example, the load when a wheelchair user weighing 100 kg or a wheelchair user weighing 120 kg sits on it. The amount of sinking of the seat cushion part at this time can be called the maximum sinking amount.

[0013] In a second aspect of the present disclosure, the folding mechanism includes a support member that supports the operating unit so as to be switchable between a first operating state in which the operating unit is raised upward and a second operating state in which the operating unit is tilted down, and is configured such that a switching operation of the operating unit from the second operating state to the first operating state changes the left support arm and the right support arm from an unfolded state to a folded state, and a switching operation of the operating unit from the first operating state to the second operating state changes the left support arm and the right support arm from a folded state to an unfolded state.

[0014] According to this configuration, when the wheelchair is folded from the unfolded state, it is only necessary to operate the tilted operating unit upward to make it stand up, and the folding operation can be easily performed. Also, when the wheelchair is unfolded from the folded state, it is only necessary to tilt the standing operating unit, and the unfolding operation can be easily performed. And, since the operating unit is tilted when the wheelchair user sits down, it is possible to make the wheelchair in a position that is difficult to contact with the seat cushion part.

[0015] In a third aspect of the present disclosure, the seat frame is configured to be detachable from the left side frame and the right side frame, and an upper end of the operating part in the first operating state is positioned higher than an upper end of the seat frame.

[0016] According to this configuration, the seat frame can be removed from the left side frame and the right side frame before folding the wheelchair, and then the wheelchair can be folded. For example, when loading the wheelchair into a car, the seat frame alone can be lifted and loaded, and then the body of the wheelchair alone can be lifted and loaded. This reduces the weight to be lifted at one time when loading the wheelchair into the car, making the task of loading the wheelchair into the car easier. When the operating unit is in the first operating state, i.e., the folded state, the upper end of the operating unit is positioned above the upper end of the seat frame, so that it comes into contact with the seat cushion. This makes it possible to know that the wheelchair is in the folded state, and prevents forgetting to unfold the wheelchair.

[0017] In a fourth aspect of the present disclosure, the operating unit can be disposed directly below the seat cushion portion. This allows the operating unit to be hidden by the seat cushion portion when the seat frame is attached, thereby preventing erroneous operation of the operating unit.

[0018] In a fifth aspect of the present disclosure, the seating frame includes a left seating frame extending in the front-rear direction of the vehicle body along the left side frame, and a right seating frame extending in the front-rear direction of the vehicle body along the right side frame. The operating unit can be disposed between the left seating frame and the right seating frame in a plan view. Also, the seat cushion unit can be provided continuously from the left seating frame to the right seating frame.

[0019] According to this configuration, the operating part is disposed between the left and right seating frames that constitute the seat frame, so that the balance when operating the operating part is good. In this case, it is possible to prevent the operating part from coming into contact with the seat cushion part that is located above the operating part. Effect of the Invention

[0020] As described above, the operating part used when performing the folding operation is positioned with a specified space below the upper end of the seating frame, so that the operating part does not cause discomfort to the seated wheelchair user, thereby making it possible to improve the riding comfort. [Brief description of the drawings]

[0021] [Figure 1] 1 is a perspective view of a wheelchair according to an embodiment of the present invention, seen from above. [Diagram 2] FIG. 2 is a perspective view showing the wheelchair body with the seat removed. [Diagram 3] FIG. [Figure 4] FIG. 1 is a left side view of a wheelchair according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a perspective view of the folded wheelchair body seen from above. [Figure 6] FIG. 2 is a plan view of the folded wheelchair body. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] 4 is a perspective view of the rear side of the right side frame as viewed from the upper left. FIG. [Figure 10] 4 is a perspective view of the front side of the right side frame as viewed from the upper left. FIG. [Figure 11] FIG. 2 is a plan view of the support arm and folding mechanism. [Figure 12] FIG. 2 is a perspective view of the support arm and the folding mechanism from the upper left. [Figure 13]FIG. 4 is a plan view of the first left support arm. [Figure 14] 14 is a cross-sectional view taken along line XIV-XIV in FIG. 11. [Figure 15] 1 is an enlarged perspective view of the vicinity of an operating unit of the folding mechanism as viewed from the upper right. [Figure 16] FIG. 2 is a partial cross-sectional view showing the seat before it is attached to the wheelchair body. [Figure 17] FIG. [Figure 18] FIG. 17 is a view equivalent to FIG. 16 showing the seat placed on the wheelchair body before the seat back frame is raised. [Figure 19] 17 is a view equivalent to FIG. 16, showing a state in which the seat back frame is raised. FIG. [Figure 20] FIG. 17 is a view corresponding to FIG. 16 according to a first modified example of the embodiment. [Figure 21] FIG. 18 is a view according to a first modified example of the embodiment. [Figure 22] FIG. 20 is a view corresponding to FIG. 19 according to a first modified example of the embodiment. [Figure 23] FIG. 17 is a view corresponding to FIG. 16 according to a second modified example of the embodiment. [Figure 24] FIG. 18 is a view according to a second modified example of the embodiment. [Diagram 25] FIG. 20 is a view corresponding to FIG. 19 according to a second modified example of the embodiment. [Figure 26] FIG. 17 is a view corresponding to FIG. 16 according to a third modified example of the embodiment. [Figure 27] FIG. 20 is a view corresponding to FIG. 19 according to a third modified example of the embodiment. [Figure 28] FIG. 13 is a diagram showing a case where the lock is released according to the third modification of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses.

[0023] Fig. 1 is a perspective view of a wheelchair 1 according to an embodiment of the present invention, seen obliquely from above and ahead. As shown in Fig. 2, this wheelchair 1 is configured to be separable into a wheelchair body 2 and a seat 3 without the need for tools. The seat 3 is shown in Fig. 3. Fig. 4 is a left side view of the wheelchair 1 with the seat 3 attached. Moreover, with the seat 3 removed, the wheelchair body 2 is configured to be foldable, as shown in Figs. 5 and 6, and therefore the wheelchair 1 according to this embodiment is a foldable wheelchair.

[0024] In addition, while Fig. 2 shows the seat cushion portion 4 and the back cushion portion 5 of the seat 3, Fig. 1 and Fig. 4 do not show the seat cushion portion 4 and the back cushion portion 5. In Fig. 3, only the outer shapes of the seat cushion portion 4 and the back cushion portion 5 are shown by virtual lines. The specific configuration of the seat 3 will be described later.

[0025] In addition, in the description of this embodiment, the direction of travel of the wheelchair 1 when moving forward is simply referred to as "front," and the front of the wheelchair 1 corresponds to the front of the wheelchair user (not shown) seated in the wheelchair 1. In addition, the direction of travel of the wheelchair 1 when moving backward is simply referred to as "rear," and the rear of the wheelchair 1 corresponds to the rear of the wheelchair user seated in the wheelchair 1. The front-to-rear direction of the wheelchair 1 is also the longitudinal direction of the body. In addition, the left side of the wheelchair user seated in the wheelchair 1 is the left side of the body of the wheelchair 1, and is simply referred to as "left." In addition, the right side of the wheelchair user seated in the wheelchair 1 is the right side of the body of the wheelchair 1, and is simply referred to as "right." The left-to-right direction of the wheelchair 1 is also the width direction of the body. In addition, the "upper side" of the wheelchair 1 is the side that is the top when placed on a horizontal surface in a seatable state, and the "lower side" of the wheelchair 1 is the side that is the bottom when placed on a horizontal surface in a seatable state.

[0026] (Structure of the wheelchair body) As shown in FIG. 1, FIG. 4, etc., the wheelchair body 2 includes left and right drive wheels 10, 11, left and right casters 12, 13, and left and right side frames 20, 30. The drive wheels 10, 11 are large-diameter wheels that the wheelchair user holds in his / her hands to rotate forward or backward, and are also called rear drive wheels because they are provided on the rear side of the wheelchair body 2. The structure of the drive wheels 10, 11 is not particularly limited, but in this embodiment, rubber tires 10b, 11b are attached to wheels 10a, 11a molded from carbon fiber reinforced plastics (CFRP). Hand rims 10c, 11c are provided on the outer sides of the wheels 10a, 11a in the vehicle width direction for the wheelchair user to hold in his / her hands when driving. In addition, in FIG. 1, FIG. 2, and FIG. 4, the symbol B denotes a brake. The brake B is a conventionally known brake that is manually switched between a braking state and a release state.

[0027] The casters 12, 13 are wheels for changing the direction of travel of the wheelchair 1, and have a smaller diameter than the drive wheels 10, 11. The casters 12, 13 are provided on the front side of the wheelchair body 2, and therefore can also be called front wheels for changing the direction of travel.

[0028] As shown in Fig. 7, the left side frame 20 includes an upper frame portion 21 extending in the front-rear direction and a caster support portion 22. Fig. 7 shows the left side frame 20 when the wheelchair 1 is placed on a horizontal surface, and as shown in this figure, the upper frame portion 21 is gently inclined so that it is positioned higher as it goes forward. The inclination angle of the upper frame portion 21 does not have to be the angle shown in the figure, and it may be horizontal. The upper frame portion 21 and the caster support portion 22 are integrally molded from the above-mentioned CFRP, and therefore the left side frame 20 is composed of a single part. The left side frame 20 may be composed of a metal material, or may be composed by joining multiple parts.

[0029] An axle insertion hole 21a into which the right side of the axle 10d of the left driving wheel 10 is inserted and fixed is formed at the rear end of the upper frame portion 21. With the right side of the axle 10d fixed to the rear end of the upper frame portion 21, the left driving wheel 10 is journaled so as to be rotatable about an axis extending in the left-right direction relative to the left side frame 20.

[0030] A front protrusion 21b that protrudes forward is provided at the front end of the upper frame portion 21. A wheelchair user in a seated position can hold the front protrusion 21b with his / her hand. A through hole 21c that penetrates in the left-right direction is formed in the middle of the upper frame portion 21 in the front-rear direction, thereby reducing the weight of the left side frame 20. The through hole 21c can be long in the front-rear direction.

[0031] A rear recess 21d formed so as to be recessed forward is provided at the rear end of the upper frame portion 21. The rear recess 21d is a portion with which a part of the seat 3 engages, as will be described later.

[0032] A storage recess 23 for accommodating a left seating frame 90 (described later) of the seat 3 is formed on the right side surface of the upper frame portion 21. The storage recess 23 is open upward, so that the seating frame 90 can be accommodated in the storage recess 23 from above. The storage recess 23 also opens to the right side, i.e., toward the inside in the width direction of the vehicle body, so that the inner surface of the storage recess 23 can be seen from the right.

[0033] The accommodating recess 23 is composed of three portions. That is, the front portion of the accommodating recess 23 is a front accommodating recess (left engagement recess) 24, and the rear portion of the accommodating recess 23 is a rear accommodating recess (left engagement recess) 25. Furthermore, the portion of the accommodating recess 23 between the front accommodating recess 24 and the rear accommodating recess 25 is an intermediate accommodating recess 26. A through hole 21c is located between the front accommodating recess 24 and the rear accommodating recess 25. Furthermore, the through hole 21c is located below the intermediate accommodating recess 26.

[0034] The depth (vertical) dimensions of the front accommodating recess 24 and the rear accommodating recess 25 are set longer than the dimension of the intermediate accommodating recess 26 in the same direction, and therefore the front accommodating recess 24 and the rear accommodating recess 25 are formed deeper than the intermediate accommodating recess 26. The front-to-rear dimensions of the front accommodating recess 24 and the rear accommodating recess 25 are approximately the same. The front-to-rear dimension of the intermediate accommodating recess 26 is set longer than the front-to-rear dimensions of the front accommodating recess 24 and the rear accommodating recess 25, and therefore the intermediate accommodating recess 26 has a shape that is long in the front-to-rear direction.

[0035] The surfaces located on the front and rear sides of the inner surface of the front housing recess 24 are the front engagement surface 24a and the rear engagement surface 24b. The vertical dimension of the front engagement surface 24a is set longer than the horizontal dimension. Similarly, the vertical dimension of the rear engagement surface 24b is set longer than the horizontal dimension. The front engagement surface 24a and the rear engagement surface 24b extend in the vertical direction and are formed so as to approach each other downward. That is, the front engagement surface 24a is configured as an inclined surface located further rearward as it goes downward, and the rear engagement surface 24b is configured as an inclined surface located further forward as it goes downward. Therefore, the distance between the front engagement surface 24a and the rear engagement surface 24b becomes narrower as it goes downward. The lower ends of the front engagement surface 24a and the rear engagement surface 24b are spaced apart in the front-rear direction.

[0036] 8, the front engagement surface 24a and the rear engagement surface 24b are formed so as to approach each other toward the right, i.e., toward the inside in the width direction of the vehicle body. That is, the front engagement surface 24a extends so as to be positioned further rearward toward the right, and the rear engagement surface 24b extends so as to be positioned further forward toward the right. The right edge of the front engagement surface 24a and the right edge of the rear engagement surface 24b are spaced apart from each other in the front-to-rear direction, and this portion opens the front storage recess 24 to the right.

[0037] The bottom surface 24c of the front housing recess 24 extends from the lower end of the front engagement surface 24a to the lower end of the rear engagement surface 24b. As shown in FIG. 7, the left side surface 24d of the inner surface of the front housing recess 24 extends from the left edge of the front engagement surface 24a to the left edge of the rear engagement surface 24b. A recess 24e is formed on the left side surface 24d as a locked portion, which will be described later, so as to be recessed to the left. The recess 24e is located above the vertical center of the left side surface 24d and approximately in the center in the front-rear direction. The shape of the recess 24e is not particularly limited, but in this embodiment, the dimension in the front-rear direction is set longer than the dimension in the up-down direction when viewed from the right side. The depth (dimension in the left-right direction) of the recess 24e is set so that the center in the up-down direction is the deepest.

[0038] The rear accommodating recess 25 is configured similarly to the front accommodating recess 24. The front engagement surface 25a and the rear engagement surface 25b of the rear accommodating recess 25 extend in the vertical direction and are formed so as to approach each other downwards, similar to the front engagement surface 24a and the rear engagement surface 24b of the front accommodating recess 24. As shown in FIG. 8, the rear accommodating recess 25 is formed so as to approach each other toward the right. As shown in FIG. 7, the bottom surface 25c of the rear accommodating recess 25 is located directly above the axle insertion hole 21a. In addition, a recess 25e is formed as a locked portion on the left side surface 25d of the inner surface of the rear accommodating recess 25 so as to be recessed to the left. The front recess 24e and the rear recess 25e may have the same shape or different shapes.

[0039] As shown in Fig. 7, the caster support part 22 extends obliquely downward from the middle part of the upper frame part 21 in the front-rear direction toward the front. As shown in Fig. 8, the caster support part 22 curves so that the lower it goes, the more to the left, that is, the more outwardly it is positioned in the width direction of the vehicle body. As shown in Fig. 4, the lower end part of the caster support part 22 is separated forward from the left driving wheel 10 by a predetermined distance or more, and the left caster 12 is attached to this lower end part so as to be rotatable about a center line extending in the vertical direction. The caster 12 is located directly below the front protrusion part 21b of the upper frame part 21.

[0040] As shown in Fig. 2 etc., the right side frame 30 has a structure symmetrical to the left side frame 20, and includes an upper frame portion 31 and a caster support portion 32. As shown in Fig. 9, the upper frame portion 31 is formed with an axle insertion hole 31a into which the left side of the axle 11d (shown in Fig. 14) of the right driving wheel 11 is inserted and fixed. The right driving wheel 11 is supported rotatably about an axis extending in the left-right direction relative to the right side frame 30, with the left side of the axle fixed to the rear end portion of the upper frame portion 31.

[0041] As shown in Fig. 10, a front protrusion 31b is provided at the front end of the upper frame portion 31, and a through hole 31c is formed in the middle of the upper frame portion 31 in the front-rear direction. A rear recess 31d (shown in Fig. 9) formed to be recessed forward is provided at the rear end of the upper frame portion 31. Note that Fig. 9 also shows a part of the right angle change portion 84, which is a member that constitutes a part of the seat 3, and this right angle change portion 84 hides a part of the rear end of the upper frame portion 31.

[0042] 2, a storage recess 33 for accommodating a right seating frame 91 (described later) of the seat 3 is formed on the left side surface of the upper frame portion 31. The storage recess 33 is open upward and to the left, and the inner surface of the storage recess 33 can be seen from the left.

[0043] As shown in Figures 9 and 10, the accommodating recess 33 has a front accommodating recess (right-side engaging recess) 34, a rear accommodating recess (right-side engaging recess) 35, and an intermediate accommodating recess 36. As shown in Figure 10, the front engaging surface 34a and the rear engaging surface 34b of the front accommodating recess 34 extend in the vertical direction and are formed so as to approach each other downward and to approach each other leftward. A bottom surface 34c and a right side surface 34d are formed on the inner surface of the front accommodating recess 34. A recessed portion 34e serving as an engaged portion is formed on the right side surface 34d so as to be recessed to the right.

[0044] 9, the rear accommodating recess 35 is configured similarly to the front accommodating recess 34, and the front engagement surface 35a and the rear engagement surface 35b extend in the vertical direction and are formed so as to approach each other downward and to approach each other rightward. A bottom surface 35c of the rear accommodating recess 35 is located directly above the axle insertion hole 31a. A recess 35e serving as a locked portion is formed on a right side surface 35d of the rear accommodating recess 35 so as to recess to the right.

[0045] 1 and other figures, the caster support part 32 extends obliquely downward toward the front from the middle part in the front-rear direction of the upper frame part 31, and curves so as to be positioned more to the right as it goes downward. The right caster 13 is attached to the lower end part of the caster support part 32 so as to be rotatable about a center line extending in the vertical direction.

[0046] (Configuration of foot rest) As shown in Fig. 1, a foot rest 40 is provided at the front of the wheelchair body 2 on which a seated wheelchair user places his / her feet. The foot rest 40 includes a left rest arm 41 connected to the lower end of the caster support part 22 of the left side frame 20 so as to be rotatable in the vertical direction, a right rest arm 42 connected to the lower end of the caster support part 32 of the right side frame 30 so as to be rotatable in the vertical direction, and a connecting plate 43 that rotatably connects the right end of the left rest arm 41 and the left end of the right rest arm 42 to each other. The center line of the rotation extends in the front-rear direction. The left rest arm 41 is provided with a left plate 41a on which the left foot is placed, and the right rest arm 42 is provided with a right plate 42a on which the right foot is placed.

[0047] 1 and 2, when the wheelchair main body 2 is in the unfolded state, the left mounting arm 41 and the right mounting arm 42 are in a position extending horizontally. On the other hand, as shown in Fig. 5, when the wheelchair main body 2 is in the folded state, the left mounting arm 41 and the right mounting arm 42 are folded in the left-right direction and are in a position extending substantially in the vertical direction, and the connecting plate 43 is disposed on top. In other words, the left mounting arm 41 and the right mounting arm 42 are relatively rotatable so as not to impede the folding operation of the wheelchair main body 2.

[0048] (Unfolding and folding the wheelchair body) The wheelchair body 2 is configured so that it can be changed from the unfolded state shown in Figs. 1 and 2 to the folded state shown in Figs. 5 and 6 without using tools or the like, and can be changed from the folded state to the unfolded state. In the unfolded state, the distance between the left side frame 20 and the right side frame 30 is enlarged, making it possible to attach the seat 3. On the other hand, in the folded state, the distance between the left side frame 20 and the right side frame 30 is narrowed, making it impossible to attach the seat 3. In this embodiment, the seat 3 is configured to be detachable from the wheelchair body 2, so that when the wheelchair 1 is not in use, the seat 3 can be removed from the wheelchair body 2 to separate the wheelchair body 2 and the seat 3, making it lighter to carry and compact. In addition, since the wheelchair body 2 is foldable, the wheelchair body 2 becomes compact. The structure that allows the wheelchair body 2 to be foldable will be described in detail below.

[0049] (Support arm) As an example of a structure that allows the wheelchair body 2 to be folded, in this embodiment, a structure using a plurality of support arms 51, 52, 61, 62 is adopted. Specifically, the wheelchair body 2 includes a first left support arm 51 and a second left support arm 52 that are rotatably connected to the left side frame 20, and a first right support arm 61 and a second right support arm 62 that are rotatably connected to the right side frame 30. The first left support arm 51 and the first right support arm 61 have the same length and are symmetrical. In addition, the second left support arm 52 and the second right support arm 62 have the same length and are symmetrical. Furthermore, the wheelchair body 2 also includes a folding mechanism 70 that can be operated by hand. The first left support arm 51 and the first right support arm 61 may be asymmetrical, and the second left support arm 52 and the second right support arm 62 may also be asymmetrical.

[0050] 11, a base end (one end) of the first left side support arm 51 is connected to a lower part of a portion forward of the front-rear center of the upper frame part 21 of the left side frame 20 via a connecting shaft 51a extending in the vertical direction so as to be rotatable in the front-rear direction. Also, a base end (one end) of the second left side support arm 52 is connected to a lower part of a portion rearward of the front-rear center of the upper frame part 21 of the left side frame 20 via a connecting shaft 52a extending in the vertical direction so as to be rotatable in the front-rear direction. Therefore, the second left side support arm 52 is provided rearward of the first left side support arm 51.

[0051] The right support arms 61, 62 are similar to the left support arms 51, 52, and the base end (one end) of the first right support arm 61 is connected to a lower part of a portion forward of the center of the front-rear direction of the upper frame part 31 of the right side frame 30 via a connecting shaft 61a extending in the vertical direction so as to be rotatable in the front-rear direction. The base end (one end) of the second right support arm 62 is connected to a lower part of a portion rearward of the center of the front-rear direction of the upper frame part 31 of the right side frame 30 via a connecting shaft 62a extending in the vertical direction so as to be rotatable in the front-rear direction. The center lines of the four connecting shafts 51a, 52a, 61a, 62a are parallel to each other. The four connecting shafts 51a, 52a, 61a, 62a may be vertical or inclined with respect to the vertical line, as long as they extend in the vertical direction. The folding operation is possible even if the four connecting shafts 51a, 52a, 61a, 62a are slightly tilted forward or backward, for example.

[0052] 4, when the wheelchair 1 is placed on a horizontal surface and viewed from the left side, as described above, the upper frame portion 21 of the left side frame 20 is inclined so that it is positioned higher as it moves toward the front. The upper frame portion 31 of the left side frame 30 is also inclined in a similar manner. Therefore, the first left support arm 51 and the first right support arm 61, which are positioned in front of the second left support arm 52 and the second right support arm 62, are positioned higher than the second left support arm 52 and the second right support arm 62.

[0053] As shown in Figures 1, 2 and 11, when the wheelchair body 2 is in the unfolded state, the left support arms 51, 52 and the right support arms 61, 62 are all in a position extending in the left-right direction to widen the gap between the left side frame 20 and the right side frame 30. In this state, the first left support arm 51 and the first right support arm 61 are aligned to form a straight line extending in the left-right direction, and the second left support arm 52 and the second right support arm 62 are aligned to form a straight line extending in the left-right direction. In addition, the tip portion, which is the right end portion, of the first left support arm 51 extends to the center between the left side frame 20 and the right side frame 30 in the left-right direction, and the tip portion, which is the left end portion, of the first right support arm 61 also extends to the center between the left side frame 20 and the right side frame 30 in the left-right direction.

[0054] 5 and 6, when the first left support arm 51 is rotated around the connecting shaft 51a so that the tip (other end) moves rearward, the first right support arm 61 is rotated around the connecting shaft 61a so that the tip (other end) moves rearward, and the second left support arm 52 is rotated around the connecting shaft 52a so that the tip (other end) moves rearward, and the second right support arm 62 is rotated around the connecting shaft 62a so that the tip (other end) moves rearward, the distance between the left side frame 20 and the right side frame 30 can be narrowed, and the wheelchair main body 2 can be folded. In this folded state, the first left support arm 51 and the first right support arm 61 are in a position extending in the front-rear direction, and the second left support arm 52 and the second right support arm 62 are in a position extending in the front-rear direction. In this embodiment, the first left support arm 51 and the first right support arm 61 are aligned in the left-right direction and parallel to each other, but this is not limiting, and the first left support arm 51 and the first right support arm 61 may not be parallel, and may be arranged such that the distance between them increases toward the base ends of the support arms 51, 61. The same is true for the second left support arm 52 and the second right support arm 62. When folding, the left support arm 41 and the right support arm 42 of the foot rest part 40 rotate upward, and the folding operation of the foot rest part 40 is performed at the same time.

[0055] The left support arms 51, 52 and the right support arms 61, 62 are configured not to rotate forward from the unfolded state. That is, as shown in Fig. 11, when the first left support arm 51 tries to rotate forward from the unfolded state, the edge 51b on the base end side of the first left support arm 51 abuts against the upper frame part 21, preventing the forward rotation. The second left support arm 52 is also prevented from rotating forward by the edge 52b, and the first right support arm 61 is also prevented from rotating forward by the edge 61b, and further, the second right support arm 62 is also prevented from rotating forward by the edge 62b. The configuration for preventing the forward rotation is not limited to the above-mentioned configuration, and may be another configuration, for example, a configuration in which a stopper or the like is provided.

[0056] (Folding mechanism) Next, the configuration of the folding mechanism 70 shown in Figs. 11 and 12 will be described. The folding mechanism 70 is provided between the left side frame 20 and the right side frame 30, and connects the first left support arm 51 and the first right support arm 61 so as to be foldable in the left-right direction, and connects the second left support arm 52 and the second right support arm 62 so as to be foldable in the left-right direction. Specifically, the folding mechanism 70 includes a front connecting member 71, a rear connecting member 72, an interlocking member 73, an operating unit 74, a gripping unit 75, a left driven gear unit (first gear unit) 76, a right driven gear unit (first gear unit) 77, and a driving gear unit (second gear unit) 78. Only one of the left driven gear unit 76 and the right driven gear unit 77 may be provided. Hereinafter, each member constituting the folding mechanism 70 will be described in detail.

[0057] (Driven gear part) As shown in FIG. 13, the left driven gear portion 76 is provided integrally with the tip of the first left support arm 51 so that the first left support arm 51 and the left driven gear portion 76 do not rotate relative to each other. A vertically extending support shaft 51c is inserted into the tip of the first left support arm 51. The support shaft 51c is configured not to come off from the tip of the first left support arm 51. The multiple teeth that constitute the left driven gear portion 76 are arranged at the tip of the first left support arm 51 so as to draw an arc-shaped locus centered on the support shaft 51c. Therefore, the center line of rotation of the left driven gear portion 76 extends in the vertical direction.

[0058] 11, the multiple teeth constituting the right driven gear portion 77 are arranged so as to describe an arc-shaped locus centered on the support shaft 61c that is inserted through the tip portion of the first right support arm 61 and is retained in place. Therefore, the rotation center line of the right driven gear portion 77 also extends in the vertical direction. The rotation center lines of the left driven gear portion 76 and the right driven gear portion 77 are parallel to the connecting shaft 51a.

[0059] The left driven gear portion 76 and the right driven gear portion 77 are disposed at a predetermined interval in the left-right direction. The number of teeth of the left driven gear portion 76 and the number of teeth of the right driven gear portion 77 are the same.

[0060] (Connecting parts) As shown in FIG. 12, the front connecting member 71 is made of a plate material extending in the left-right direction, and two identical front connecting members 71 are provided with a gap between them. The size of the gap between the front connecting members 71, 71 is set so that the tip ends of the first left support arm 51 and the first right support arm 61 can be inserted therein. A grip 75 is connected to the front part of the front connecting member 71. On the other hand, as shown in FIG. 11, the tip of the first left support arm 51 is connected to the left side of the rear part of the front connecting member 71 by a support shaft 51c, and the tip of the first right support arm 61 is connected to the right side of the rear part of the front connecting member 71 by a support shaft 61c. The first left support arm 51 is rotatable around the support shaft 51c, and the first right support arm 61 is rotatable around the support shaft 61c. Therefore, the tip end of the first left support arm 51 and the tip end of the first right support arm 61 are rotatably connected by the front connecting member 71, and the rear end (base end) of the grip portion 75 is connected to the tip end of the first left support arm 51 and the tip end of the first right support arm 61 by the front connecting member 71. The support shaft 61c is parallel to the connecting shaft 61a.

[0061] The rear connecting member 72 is disposed rearward away from the front connecting member 71. The rear connecting member 72 is a thick plate extending in the front-rear direction, and is connected to the tip of the second left support arm 52 by a support shaft 72a extending in the vertical direction, and is connected to the tip of the second right support arm 62 by a support shaft 72b extending in the vertical direction. The second left support arm 52 is rotatable about the support shaft 72a, and the second right support arm 62 is rotatable about the support shaft 72b. The rear connecting member 72 is provided with a hollow portion 72c into which the tip side of the second left support arm 52 and the tip side of the second right support arm 62 are inserted. The support shafts 72a and 72b are parallel to the connecting shaft 52a.

[0062] A ring-shaped portion 72d formed in a ring shape is provided at the rear portion of the rear connecting member 72. The ring-shaped portion 72d protrudes rearward from the second left support arm 52 and the second right support arm 62. This ring-shaped portion 72d may be provided as necessary, and may be omitted or may have another shape.

[0063] (Interlocking parts) The interlocking member 73 is a member that connects the front connecting member 71 and the rear connecting member 72, and is formed in a rod shape extending in the front-rear direction. The rear end of the interlocking member 73 is fixed to the center in the left-right direction at the front of the rear connecting member 72. Meanwhile, the front end of the interlocking member 73 is rotatably connected to the support shaft 51c at the tip of the first left support arm 51 and the support shaft 61c at the tip of the first right support arm 61. The tip of the first left support arm 51 and the tip of the first right support arm 61 are rotatable around the support shaft 51c and the support shaft 61c with respect to the front end of the interlocking member 73. Therefore, the first left support arm 51 and the first right support arm 61 can be connected to the second left support arm 52 and the second right support arm 62 by the interlocking member 73 to be interlocked.

[0064] (Operation section and drive gear section) The operation unit 74 is a member for a person (operator) performing a folding operation, such as a wheelchair user or an assistant, to manually operate the folding mechanism 70, and is disposed in the center between the left side frame 20 and the right side frame 30 in the left-right direction. The operation direction of this operation unit 74 is the up-down direction. That is, as shown in Figs. 14 and 15, a support shaft (support member) 74a extending in the left-right direction is inserted into the base end of the operation unit 74, and the operation unit 74 is rotatably supported by this support shaft 74a. The left end of the support shaft 74a is supported by the left bearing portion 74b, and the left end of the support shaft 74a is supported by the right bearing portion 74c. The left bearing portion 74b is disposed on the left side of the upper surface of the front connecting member 71, and is integrated with the upper end of the support shaft 51c. The right bearing portion 74c is disposed on the right side of the upper surface of the front connecting member 71, and is integrated with the upper end of the support shaft 61c.

[0065] A portion of the operating unit 74 radially away from the support shaft 74a is formed in a ring shape. This allows the operator to insert his / her hand into the operating unit 74 to grip it or hold it. The size of the operating unit 74 can be any size, and is preferably large enough to allow at least a finger to be inserted. The operating unit 74 may be formed in a rod shape rather than a ring shape. When the operating unit 74 is rod-shaped, it is preferable that the rod-shaped operating unit 74 has a structure including a portion extending radially from the support shaft 74a and a portion extending parallel to the support shaft 74a.

[0066] As shown in FIG. 14, a driving gear unit 78 is integrally provided at the base end of the operating unit 74, so that the driving gear unit 78 and the base end of the operating unit 74 do not rotate relative to each other. A plurality of teeth constituting the driving gear unit 78 are arranged so as to draw an arc-shaped locus centered on the support shaft 74a at the base end of the operating unit 74. Therefore, the rotation center line of the driving gear unit 78 extends in the left-right direction. Since the operating unit 74 and the driving gear unit 78 are integrated, the driving gear unit 78 can be driven around the support shaft 74a by rotating the operating unit 74 around the support shaft 74a, and the operating unit 74 at this time rotates around the same center line as the rotation center line of the driving gear unit 78. In other words, the support shaft 74a is a member that supports the operating unit 74 so that it can be rotated around the same center line as the rotation center line of the driving gear unit 78.

[0067] The support shaft 74a is disposed above the first left support arm 51 and the first right support arm 61. As a result, the rotation center line of the drive gear unit 78 and the operation unit 74 are disposed above the first left support arm 51 and the first right support arm 61. When operating the operation unit 74, it is held in the hands from above, but since the operation unit 74 is located above the first left support arm 51 and the first right support arm 61, the first left support arm 51 and the first right support arm 61 do not get in the way when holding the operation unit 74 in the hands, improving operability.

[0068] The width of the teeth of the drive gear portion 78 (the dimension in the left-right direction) is set so as to reach from the left driven gear portion 76 to the right driven gear portion 77. This allows the teeth of the drive gear portion 78 to mesh with the teeth of both the left driven gear portion 76 and the right driven gear portion 77. In other words, the two driven gear portions 76, 77 can be driven by one drive gear portion 78, thereby reducing the number of parts. In addition, the timing at which the driven gear portions 76, 77 start to rotate and the rotation speed can be made the same.

[0069] Furthermore, the rotation center line of the drive gear portion 78 extends in the left-right direction, while the rotation center lines of the left driven gear portion 76 and the right driven gear portion 77 extend in the up-down direction. Even if the rotation center lines are perpendicular to each other in this manner, by locating the rotation center line of the drive gear portion 78 above the left driven gear portion 76 and the right driven gear portion 77, smooth transmission of force is possible.

[0070] (Folding and unfolding operations using the operating unit) The folding mechanism 70 is configured to change the first left support arm 51, the first right support arm 61, the second left support arm 52, and the second right support arm 62 from a folded state to an unfolded state, and from an unfolded state to a folded state, by operating the operation unit 74. Specifically, the operation unit 74 can be rotated around a support shaft 74a, and is supported rotatably by the support shaft 74a, so that the operation unit 74 can be switched between an upright state (first operation state) in which the operation unit 74 is upright upward as shown in Figs. 5 and 6, and a non-upright state (second operation state) in which the operation unit 74 is tilted down as shown in Figs. 11, 12, and 14. In this embodiment, the operation unit 74 is switched to the non-upright state by tilting the operation unit 74 in the upright state toward the rear side of the vehicle body, and the operation unit 74 is switched to the upright state by raising the operation unit 74 in the non-upright state toward the front side of the vehicle body. An operation of tilting the operating unit 74 toward the rear of the vehicle body is a downward operation, and an operation of lifting the operating unit 74 toward the front of the vehicle body is an upward operation. Although not shown, the operating unit 74 may be configured to be able to be tilted toward the front of the vehicle body.

[0071] Then, by switching the operation unit 74 from a non-standing state to a standing state, the first left support arm 51 and the first right support arm 61 and the second left support arm 52 and the second right support arm 62 are changed from the unfolded state to the folded state. Also, by switching the operation unit 74 from a standing state to a non-standing state, the first left support arm 51 and the first right support arm 61 and the second left support arm 52 and the second right support arm 62 are changed from the folded state to the unfolded state.

[0072] More specifically, when the operating unit 74 is switched from the non-standing state to the standing state, the operating unit 74 is raised upward. This operation is an operation in a predetermined direction. Since the driving gear unit 78 is integrally provided with the operating unit 74, the driving gear unit 78 rotates forward around the support shaft 74a by operating the operating unit 74 in a predetermined direction. When the driving gear unit 78 rotates, a rotational force is transmitted to the left driven gear unit 76 and the right driven gear unit 77 meshing with the driving gear unit 78, and the left driven gear unit 76 and the right driven gear unit 77 try to rotate around the center line in the vertical direction. At this time, the base end of the first left support arm 51 with which the left driven gear unit 76 is integrally provided can rotate with respect to the left side frame 20 by the support shaft 51a, and the base end of the first right support arm 61 with which the right driven gear unit 77 is integrally provided can rotate with respect to the right side frame 30 by the support shaft 61a. Furthermore, the tip of the first left support arm 51 and the tip of the first right support arm 61 are both rotatable with respect to the front connecting member 71. Therefore, due to the rotational force transmitted to the left driven gear portion 76 and the right driven gear portion 77, the first left support arm 51 rotates rearward about the support shaft 51a, and the first right support arm 61 rotates rearward about the support shaft 61a. As a result, the first left support arm 51 and the first right support arm 61 change from the unfolded state to the folded state.

[0073] Since the first left support arm 51 and the first right support arm 61 are connected to the second left support arm 52 and the second right support arm 62 by the interlocking member 73, the second left support arm 52 and the second right support arm 62 also rotate about the support shafts 52a, 62a in conjunction with the rotation of the first left support arm 51 and the first right support arm 61. As a result, the second left support arm 52 and the second right support arm 62 are also simultaneously changed from the unfolded state to the folded state.

[0074] (Layout of operation unit) Here, a case where the wheelchair body 2 is lifted and moved with one hand after folding the wheelchair body 2 will be described. When lifting the wheelchair body 2 with one hand, it is difficult to know which part to hold because a general wheelchair is not even designed to be lifted with one hand, and even if it is held with one hand, the wheelchair, which is not designed to be lifted with one hand, becomes unstable, and as a result, the front part of the wheelchair may tilt so that it is positioned lower than the rear part. Since casters similar to those in this embodiment are rotatably attached to the front part of a conventional general wheelchair, when the front part of the wheelchair is lowered, the casters hang down and touch the ground, so it is necessary to lift it to a higher position. In particular, when considering the case where a wheelchair user is driving a car alone, after the wheelchair user transfers from the wheelchair to the driver's seat of the car, the wheelchair needs to be moved from outside the car to inside the car. At this time, it is difficult to lift the wheelchair with both hands, and the wheelchair needs to be lifted with one hand. In that case, the casters will hang down and come into contact with the bottom edge of the door opening, making it impossible to fit inside, so the wheelchair needs to be lifted higher, which is a great burden for the wheelchair user.

[0075] In response to this, in this embodiment, the position of the operating unit 74 is carefully considered. That is, as shown by the dashed line in FIG. 4, the operating unit 74 is disposed between the axles 10d, 11d of the drive wheels 10, 11 and the rotation center line of the casters 12, 13 in a side view of the vehicle body. The center of gravity of the wheelchair body 2 with the seat 3 removed is located near the axles 10d, 11d of the drive wheels 10, 11 in a side view. Therefore, after folding, by holding the operating unit 74 disposed between the drive wheels 10, 11 and the casters 12, 13 in a side view, the rear part of the wheelchair body 2 naturally tilts to be located lower than the front part. This prevents the casters 12, 13 from sagging.

[0076] (gripping part) As shown in Figs. 11 and 12, the gripping part 75 constituting a part of the folding mechanism 70 is a part that can be gripped when moving the wheelchair body 2 in the folded state. As described above, the wheelchair body 2 can be lifted by holding the operating part 74 in the hand, but since the operating part 74 is in an upright state when folded, it may be difficult for some people to hold it. In addition, it is considered that the ring-shaped operating part 74 is difficult to hold, and the operating part 74 is a member for operating the folding mechanism 70, and is not a member dedicated to lifting the wheelchair body 2. In response to this, in this embodiment, the gripping part 75 is provided separately from the operating part 74, making it easier to lift the wheelchair body 2. Note that the gripping part 75 may be omitted and the wheelchair body 2 may be lifted by the operating part 74.

[0077] The grip 75 is attached to the front of the front connecting member 71 and is connected to the first left support arm 51 and the first right support arm 61 via the front connecting member 71. The grip 75 extends forward from the front of the front connecting member 71. That is, as shown in FIG. 5 and FIG. 6, when the first left support arm 51 and the first right support arm 61 are in the folded state, the tip end of the support arm 51, 61 is located behind the base end, and when the first left support arm 51 and the first right support arm 61 in the folded state are switched to the unfolded state, the first left support arm 51 and the first right support arm 61 are rotated forward around the support shafts 51a, 61a by operating the operating unit 74. That is, the forward direction is the rotation direction of the first left support arm 51 and the first right support arm 61 when they are switched from the folded state to the unfolded state.

[0078] The grip 75 can be used when the wheelchair body 2 is changed from the folded state to the unfolded state. When a wheelchair user grasps the grip 75 and lifts the wheelchair body 2, the first left support arm 51 and the first right support arm 61 are rotatably connected to the left side frame 20 and the right side frame 30, while a downward force is constantly acting on the left side frame 20 and the right side frame 30 due to the influence of gravity, so the grip 75 connected to both support arms 51, 61 moves upwards relative to the left side frame 20 and the right side frame 30. This relative movement of the grip 75 causes the first left support arm 51 and the first right support arm 61 to rotate forward from the folded state to the unfolded state. Since the grip 75 extends forward, which is the rotation direction of both support arms 51, 61 when switching from the folded state to the unfolded state, the wheelchair body 2 can be unfolded by simply grasping the grip 75 with one hand and lifting it up, using the weight of the wheelchair body 2. When deploying by holding the gripping portion 75, there is no need to operate the operating portion 74.

[0079] The shape and structure of the gripping portion 75 are not particularly limited, but in this embodiment, the gripping portion 75 is composed of a plurality of portions extending in different directions. Specifically, the gripping portion 75 has a first gripping portion 75a extending linearly from a base end (rear end) connected to the first left support arm 51 and the first right support arm 61 toward the rotation direction of the first left support arm 51 and the first right support arm 61, and a second gripping portion 75b extending in the left-right direction of the vehicle body from a tip end of the first gripping portion 75a. The second gripping portion 75b may extend in both the left and right directions, or may extend in only one direction. Since the first gripping portion 75a and the second gripping portion 75b extend in different directions, a wheelchair user can select whichever is easier to hold.

[0080] (Sheet configuration) As shown in FIG. 2, the seat 3 includes a seat cushion portion 4 on which a wheelchair user sits, a back cushion portion 5, and a seat frame 7. As shown in FIG. 1, the seat frame 7 is configured to be detachable from the left side frame 20 and the right side frame 30 of the wheelchair main body 2. As shown in FIG. 3, the seat frame 7 includes a left seating frame 90, a right seating frame 91, and a seat back frame 92. As shown in FIG. 1, the left seating frame 90 extends in the front-rear direction on the left side of the lower part of the seat 3, and is aligned with the upper frame portion 21 of the left side frame 20 of the wheelchair main body 2. The right seating frame 91 extends in the front-rear direction on the right side of the lower part of the seat 3, and is aligned with the upper frame portion 31 of the right side frame 30 of the wheelchair main body 2. The operating portion 74 and the gripping portion 75 of the folding mechanism 70 are disposed between the left seating frame 90 and the right seating frame 91 in a plan view.

[0081] As shown by the imaginary lines in Fig. 3, the seat cushion section 4 extends from the left seating frame 90 to the right seating frame 91 and also extends in the front-rear direction, and is a section that constitutes a seat surface on which a wheelchair user sits. The left side of the seat cushion section 4 is supported by the left seating frame 90, and the right side of the seat cushion section 4 is supported by the right seating frame 91. Examples of materials that constitute the seat cushion section 4 include plate materials, cloth materials, net-like materials, various elastic materials, and foam materials, and the seat cushion section 4 can be a material that is configured to elastically deform downward when a wheelchair user sits on it.

[0082] With the seat 3 attached to the wheelchair body 2, the seat cushion section 4 is disposed above the operating section 74 of the folding mechanism 70. In other words, the operating section 74 is disposed directly below the seat cushion section 4. For example, the seat cushion section 4 and the operating section 74 shown by the imaginary lines in Fig. 14 are spaced apart from each other in the up-down direction, and a space is formed between them. Such a relative positional relationship between the seat cushion section 4 and the operating section 74 can be established by the structure and shape of the seat frame 7.

[0083] Specifically, the height of the upper ends of the seating frames 90, 91 and the vertical dimensions of the seating frames 90, 91 are set so that the distance between the upper end of the operating unit 74 in a non-standing state in side view and the upper ends of the seating frames 90, 91 is equal to or greater than a predetermined distance. As a result, the operating unit 74 in a non-standing state in side view is spaced below the upper ends of the seating frames 90, 91 by a predetermined distance or more, and as a result, the above-mentioned space is formed between the seat cushion unit 4 and the operating unit 74.

[0084] When a wheelchair user sits on the seat cushion portion 4, the seat cushion portion 4 sinks due to the weight of the wheelchair user. Since the operation unit 74 is disposed at a predetermined distance or more below the upper ends of the seating frames 90, 91 that support the seat cushion portion 4 in a side view, the operation unit 74 does not come into contact with the sunken seat cushion portion 4. As a result, the operation unit 74 does not come into contact with the parts of the seat cushion portion 4 that correspond to the legs and buttocks of the wheelchair user, the wheelchair user does not feel uncomfortable and the ride is comfortable.

[0085] The heavier the wheelchair user is, the greater the sinking amount of the seat cushion section 4 when the wheelchair user sits on it. However, since the operating section 74 is disposed at a predetermined distance or more below the upper ends of the seating frames 90, 91 in a side view, even if the seat cushion section 4 sinks when a heavy wheelchair user sits on it, the seat cushion section 4 is prevented from contacting the operating section 74. In other words, the predetermined distance is a size that can prevent the seat cushion section 4 from contacting the operating section 74 even if the maximum load assumed by the wheelchair acts on the seat cushion section 4. The maximum load assumed by the wheelchair can be set arbitrarily, but is, for example, the load when a wheelchair user weighing 100 kg or a wheelchair user weighing 120 kg sits on it. The sinking amount of the seat cushion section 4 at this time can be called the maximum sinking amount. Even when the sinking amount of the seat cushion section 4 reaches the maximum sinking amount, the lower surface of the seat cushion section 4 does not come into contact with the operating section 74. Since the sinking amount may differ depending on the material, structure, etc. of the seat cushion portion 4, the above-mentioned predetermined distance may be changed depending on the material, structure, etc. of the seat cushion portion 4.

[0086] As shown by virtual lines in Figure 14, the dimensions of operating unit 74 and the height of support shaft 74a are set so that when operating unit 74 is in an upright position, the upper end of operating unit 74 is positioned higher than the upper ends of seating frames 90, 91.

[0087] Furthermore, with the seat 3 attached to the wheelchair main body 2, the grip part 75 is positioned below the seat cushion part 4. As a result, the grip part 75 is hidden by the seat cushion part 4, making it difficult for the wheelchair user or a caregiver to accidentally grab the grip part 75. On the other hand, when the wheelchair main body 2 is folded and held, the seat 3 is removed, so the grip part 75 is visible from above and can be easily grabbed.

[0088] (Fitting structure between seat frame and wheelchair body) In this embodiment, when attaching the seat 3 to the wheelchair body 2, the left and right sides of the seat frame 7 are placed on the left and right side frames 20 and 20 of the wheelchair body 2, so that the seat frame 7 can be fitted to the left and right side frames 20 and 20 of the wheelchair body 2. This fitting structure prevents the seat 3 from rattling. The fitting structure of the seat frame 7 to the wheelchair body 2 will be specifically described below.

[0089] As shown in FIG. 3, a first left engaging protrusion 93 that protrudes downward is provided on the front side of the left seating frame 90. A second left engaging protrusion 94 is provided on the rear side of the left seating frame 90. The distance between the first left engaging protrusion 93 and the second left engaging protrusion 94 in the front-rear direction is the same as the distance between the front storage recess 24 and the rear storage recess 25 (shown in FIG. 7) formed in the left side frame 20 in the front-rear direction. When attaching the seat 3, the first left engaging protrusion 93 and the second left engaging protrusion 94 are disposed above the front storage recess 24 and the rear storage recess 25, and then moved downward to be inserted into the front storage recess 24 and the rear storage recess 25 from above. Therefore, the first left engaging protrusion 93 and the second left engaging protrusion 94 are portions that are inserted into the front storage recess 24 and the rear storage recess 25 from above and engaged therewith. Further, the portion of the left seating frame 90 between the first left engaging protrusion 93 and the second left engaging protrusion 94 is accommodated in an intermediate accommodating recess 26 formed in the left side frame 20 .

[0090] The first left engaging protrusion 93 is hollow and is open to the left. A front surface 93a and a rear surface 93b located on the front and rear sides, respectively, of the outer surface of the first left engaging protrusion 93 are formed to fit along the front engaging surface 24a and the rear engaging surface 24b of the front accommodating recess 24. As a result, the dimension of the first left engaging protrusion 93 in the front-to-rear direction becomes shorter as it goes downward. In addition, the lower surface of the first left engaging protrusion 93 is formed to fit along the bottom surface 24c of the front accommodating recess 24.

[0091] The second left engagement protrusion 94 is also hollow and open to the left. A front surface 94a and a rear surface 94b of the second left engagement protrusion 94 are formed to fit along the front engagement surface 25a and the rear engagement surface 25b of the rear accommodating recess 25. As a result, the dimension of the second left engagement protrusion 94 in the front-to-rear direction becomes shorter as it goes downward. In addition, the lower surface of the second left engagement protrusion 94 is formed to fit along the bottom surface 25c of the rear accommodating recess 25.

[0092] Like the left seating frame 90, the right seating frame 91 is also provided with a first right engagement protrusion 95 and a second right engagement protrusion 96 that protrude downward. The distance between the first right engagement protrusion 95 and the second right engagement protrusion 96 in the front-rear direction matches the distance between the front storage recess 34 and the rear storage recess 35 formed in the right side frame 30 in the front-rear direction. When attaching the seat 3, the first right engagement protrusion 95 and the second right engagement protrusion 96 are inserted from above into the front storage recess 34 and the rear storage recess 35 to engage them. In addition, a portion of the right seating frame 91 between the first right engagement protrusion 95 and the second right engagement protrusion 96 is accommodated in the intermediate storage recess 36 formed in the right side frame 30.

[0093] The first right engagement protrusion 95 is hollow and open to the right. A front surface 95a and a rear surface 95b of the first right engagement protrusion 95 are formed to fit along the front engagement surface 34a and the rear engagement surface 34b of the front accommodating recess 34. As a result, the dimension of the first right engagement protrusion 95 in the front-to-rear direction becomes shorter as it goes downward. In addition, the lower surface of the first right engagement protrusion 95 is formed to fit along the bottom surface 34c of the front accommodating recess 34.

[0094] The second right engagement protrusion 96 is also hollow and open to the right. A front surface 96a and a rear surface 96b of the second right engagement protrusion 96 are formed to fit along the front engagement surface 35a and the rear engagement surface 35b of the front accommodating recess 35. As a result, the dimension of the second right engagement protrusion 96 in the front-to-rear direction becomes shorter as it goes downward. In addition, the lower surface of the second right engagement protrusion 96 is formed to fit along the bottom surface 35c of the front accommodating recess 35.

[0095] Because of the above configuration, when attaching the seat 3 to the wheelchair body 2, the seat frame 7 is moved downward and the left engaging protrusions 93, 94 and the right engaging protrusions 95, 96 are inserted from above into the left storage recesses 24, 25 and the right storage recesses 34, 35, making the attachment operation easy. During attachment, the front-to-rear dimension of the lower surface of the left engaging protrusions 93, 94 is shorter than the front-to-rear dimension of the upper end of the left storage recesses 24, 25, so that the left engaging protrusions 93, 94 can be easily aligned with the left storage recesses 24, 25. The same applies to the right engaging protrusions 95, 96.

[0096] The left engaging protrusions 93, 94 and the right engaging protrusions 95, 96 are inserted into the left storage recesses 24, 25 and the right storage recesses 34, 35 and engaged with each other, so that the seat frame 7 can be fitted to the left side frame 20 and the right side frame 20. At this time, the front engaging surfaces 24a, 25a and the rear engaging surfaces 24b, 25b of the left storage recesses 24, 25 and the front engaging surfaces 34a, 35a and the rear engaging surfaces 34b, 35b of the right storage recesses 34, 35 are formed so as to approach each other as they go downward, respectively, so that the positioning of the seat frame 7 during installation can be easily performed without visually checking the engaging protrusions 93-96 and the storage recesses 24, 25, 34, 35. Note that the seat frame 7 can be easily removed by simply lifting it up when it is to be removed.

[0097] Furthermore, when a wheelchair user sits on the seat cushion portion 4, the left engaging protrusions 93, 94 and the right engaging protrusions 95, 96 of the seat frame 7 are pressed downward by the weight of the wheelchair user. As a result, the left engaging protrusions 93, 94 come into strong contact with the front engaging surfaces 24a, 25a and rear engaging surfaces 24b, 25b of the left storage recesses 24, 25, and are firmly fitted into the left storage recesses 24, 25, and the right engaging protrusions 95, 96 come into strong contact with the front engaging surfaces 34a, 35a and rear engaging surfaces 34b, 35b of the right storage recesses 34, 35, and are firmly fitted into the right storage recesses 34, 35.

[0098] The seat frame 7 includes a front cross beam 97 and a rear cross beam 98 extending in the left-right direction under the seat cushion portion 4. The front cross beam 97 extends from the right side of the first left engagement protrusion 93 to the left side of the first right engagement protrusion 95, and is a portion that connects the first left engagement protrusion 93 and the first right engagement protrusion 95. The rear cross beam 98 extends from the right side of the second left engagement protrusion 94 to the left side of the second right engagement protrusion 96, and is a portion that connects the second left engagement protrusion 94 and the second right engagement protrusion 96. In this embodiment, the left seating frame 90, the right seating frame 91, the front cross beam 97, and the rear cross beam 98 are integrally formed from the above-mentioned CFRP or the like, but the present invention is not limited thereto, and they may be formed from separate members and then joined together to be integrated.

[0099] Providing the front cross beam 97 and the rear cross beam 98 not only improves the rigidity of the seat frame 7, but also improves the rigidity of the wheelchair body 2 by indirectly connecting the left side frame 20 and the right side frame 30 of the wheelchair body 2 through the cross beams 97, 98 of the seat frame 7. In particular, by connecting and integrating the left engaging protrusions 93, 94 that fit into the left side frame 20 with the right engaging protrusions 95, 96 that fit into the right side frame 30, respectively, the effect of improving the rigidity of the wheelchair body 2 becomes even more remarkable.

[0100] (Seat folding structure) The seat 3 is configured so that the portion serving as the backrest can be reclined and folded. That is, the seatback frame 92 is attached to the rear ends of the left seating frame 90 and the right seating frame 91 so as to be rotatable about a center line extending in the left-right direction, and is a member capable of supporting the back of a wheelchair user in an upright position.

[0101] Specifically, the seatback frame 92 includes a left bar 80 and a right bar 81 that are arranged to extend vertically in an upright state, and a connecting bar 82 that connects the middle portions of the left bar 80 and the right bar 81. A back cushion section 5 made of the same material as the seat cushion section 4 is attached to the left bar 80 and the right bar 81. When the seatback frame 92 is folded, the left bar 80 and the right bar 81 are in a position in which they extend forward and are positioned above the seat cushion section 4. This allows the seat 3 to be made compact.

[0102] A conventionally known structure can be applied as the folding structure of the seatback frame 92, and in this embodiment, the left bar 80 has a left angle change portion 83. The left angle change portion 83 is provided at the lower end of the left bar 80 and is connected to the rear end of the left seating frame 90. Furthermore, the right bar 81 has a right angle change portion 84. The right angle change portion 84 is provided at the lower end of the right bar 81 and is connected to the rear end of the right seating frame 91.

[0103] The right angle changer 84 includes a fixed member 84a fixed to the rear end of the right seating frame 91, a rotating member 84b fixed to the lower end of the right bar 81 and attached rotatably around a center line extending in the left-right direction relative to the fixed member 84a, and a lock pin 84c. The lock pin 84c is inserted into a lock hole (not shown) provided in the fixed member 84a and either a first through hole or a second through hole (both not shown) provided in the rotating member 84b. The first through hole and the second through hole of the rotating member 84b are arranged at intervals from each other in the circumferential direction of the rotation center line of the seatback frame 92. For example, the positions of the first through hole and the second through hole are set so that when the lock pin 84c is inserted into the first through hole of the pivoting member 84b and the lock hole of the fixed member 84a, the seatback frame 92 can be held in an upright position, whereas when the lock pin 84c is inserted into the second through hole of the pivoting member 84b and the lock hole of the fixed member 84a, the seatback frame 92 can be held in a folded position.

[0104] Like the right angle change unit 84, the left angle change unit 83 also has a fixed member 83a, a rotating member 83b, and a lock pin (not shown). Furthermore, the lock pin 84c of the right angle change unit 84 and the lock pin of the left angle change unit 83 are connected by a lock pin connecting member 85. For example, by pulling the lock pin connecting member 85, the lock pin 84c of the right angle change unit 84 and the lock pin of the left angle change unit 83 can be removed from the lock holes to release the locked state.

[0105] The rotating member 83b of the left angle change portion 83 is provided with a left locking portion 83d that is engaged in the rear recess 21d of the left side frame 20 when the seatback frame 92 is in the upright state. Similarly, the rotating member 84b of the right angle change portion 84 is provided with a right locking portion 84d that is engaged in the rear recess 31d of the right side frame 30 when the seatback frame 92 is in the upright state. When the seatback frame 92 is folded, the left locking portion 83d and the right locking portion 84d move upward and are released from the rear recess 21d of the left side frame 20 and the rear recess 31d of the right side frame 30.

[0106] Moreover, the rotating member 83b of the left angle change portion 83 is provided with a left pressing portion 83e that presses a left slide member 113 (described later) to a locked position when the seatback frame 92 is in the upright state. The left pressing portion 83e and the left locking portion 83d are integrated. Moreover, the rotating member 84b of the right angle change portion 84 is provided with a right pressing portion 84e that presses a right slide member 103 (shown in FIG. 17, etc.) (described later) to a locked position when the seatback frame 92 is in the upright state. The right pressing portion 84e and the right locking portion 84d are integrated. When the seatback frame 92 is folded, the left side pressing portion 83e and the right side pressing portion 84e each move upward and move upward away from the left side sliding member 113 and the right side sliding member 103, respectively, while when the seatback frame 92 is in an upright position, the left side pressing portion 83e and the right side pressing portion 84e are configured to press the left side sliding member 113 and the right side sliding member 103, respectively, forward with a force greater than or equal to a predetermined value.

[0107] (Lock structure for seat to wheelchair body) The seat 3 is provided with a locking structure for preventing the seat 3 from easily coming off the wheelchair body 2 when attached to the wheelchair body 2. As shown in Fig. 17, the right seating frame 91 is provided with a first right locking member 101, a second right locking member 102, one right slide member 103, and a right coil spring (biasing member) 104. The first right locking member 101 and the second right locking member 102 are the same and are made of, for example, an elastic metal plate material or a resin material.

[0108] The first right-side locking member 101 is provided on the front side of the right side surface of the right seating frame 91 and is positioned so as to overlap, in a side view, with a recess 34e (shown in FIG. 10) formed in the front accommodation recess 34 of the right side frame 30. In a side view, the first right-side locking member 101 and the front cross beam 97 overlap each other.

[0109] The second right-side locking member 102 is provided on the rear side of the right side surface of the right seating frame 91 and is positioned so as to overlap, in side view, with a recess 35e (shown in FIG. 9) formed in the rear accommodation recess 35 of the right side frame 30. In side view, the second right-side locking member 102 and the rear cross beam 98 overlap.

[0110] The lower part of the first right locking member 101 is fixed to the right side surface of the right seating frame 91 as a fixed end, while the upper part is a free end, so that the first right locking member 101 can be deformed in the left-right direction. The vertical center part of the first right locking member 101 is formed to protrude to the right compared to the upper and lower parts, and is the part that enters the recessed part 34e. By pressing the first right locking member 101 to the right with a predetermined or more force, the center part of the first right locking member 101 is maintained in a state of protruding from the right side surface of the right seating frame 91 to the right side of the right seating frame 91 and enters the recessed part 34e. The first right locking member 101 is formed in this way. By entering the recessed part 34e, the center part of the first right locking member 101 comes into contact with the inner surface of the recessed part 34e and is locked, preventing it from coming out, so this protruding state is the locked state. In this way, the recess 34e serving as the locked portion is provided in the portion of the right side frame 30 corresponding to the first right-side locking member 101, so that the locked state can be achieved simply by molding the first right-side locking member 101 into the shape described above.

[0111] On the other hand, the unlocked state is a state in which the first right locking member 101 is permitted to move inwardly of the right seating frame 91. In the unlocked state, the first right locking member 101 elastically deforms toward the left side. For example, by leaving the wheelchair body 2 in place and lifting the seat frame 7 upward, the first right locking member 101 comes into sliding contact with the inner surface of the recessed portion 34e and is pushed toward the left side, elastically deforming toward the left side, whereby the first right locking member 101 comes out of the recessed portion 34e. When the first right locking member 101 comes out of the recessed portion 34e, the shape of the first right locking member 101 is restored.

[0112] The second right-side locking member 102 has a fixed lower end and a free upper end, similar to the first right-side locking member 101. The center portion of the second right-side locking member 102 enters and is locked in the recess 35e. On the other hand, when the second right-side locking member 102 is in the unlocked state, the center portion of the second right-side locking member 102 can come out of the recess 35e.

[0113] As shown in FIG. 17, the right slide member 103 and the right coil spring 104 are housed in the right seating frame 91. The right slide member 103 is formed in a rod shape that is long in the front-rear direction, and is disposed to the left of the first right lock member 101 and the second right lock member 102 in the right seating frame 91, and is held by the right seating frame 91 so as to be slidable in the front-rear direction. The right slide member 103 is guided by the right seating frame 91 so as to be movable only in the front-rear direction. The right slide member 103 is slidable between a locked position where the first right lock member 101 and the second right lock member 102 are held in a locked state, and an unlocked position where the first right lock member 101 and the second right lock member 102 are unlocked. In this way, the first right lock member 101 and the second right lock member 102 are switched between a locked state and an unlocked state by the single right slide member 103.

[0114] That is, the length of the right slide member 103 is set to be longer than the dimension of the right seat frame 91 in the front-rear direction. A spring abutment portion 103a against which the rear end of the right coil spring 104 abuts is formed in a rearward portion of the right slide member 103. The front end of the right coil spring 104 abuts against the inner surface of the right seat frame 91, and the biasing force of the right coil spring 104 acts on the right slide member 103 as a force that constantly biases the right slide member 103 rearward. In this embodiment, the right slide member 103 is held in a rearward slid state by the biasing force of the right coil spring 104, but as described later, in conjunction with the mounting operation of the seat 3 to the wheelchair body 2, the right slide member 103 slides forward against the biasing force of the right coil spring 104. The rearward slid state is the unlocked position of the right slide member 103, and the forward slid state is the locked position of the right slide member 103.

[0115] A front regulating portion 103b is provided at a front portion of the right slide member 103. When the right slide member 103 slides backward to be in the unlocked position, the front regulating portion 103b is located behind the first right locking member 101, whereas when the right slide member 103 slides forward to be in the locked position, the front regulating portion 103b is disposed so as to abut against the left side surface of the first right locking member 101. The front regulating portion 103b is configured to push the left side surface of the first right locking member 101 toward the right with a force equal to or greater than a predetermined value to advance the first right locking member 101 to the locked state. In other words, the front regulating portion 103b is a portion that puts the first right locking member 101 into the locked state and abuts against the first right locking member 101 in the locked state to regulate the retreat of the first right locking member 101.

[0116] A rear regulating portion 103c is provided behind the spring abutment portion 103a of the right-side sliding member 103. When the right-side sliding member 103 slides backward and is in the unlocked position, the rear regulating portion 103c is located behind the second right-side locking member 102, whereas when the right-side sliding member 103 slides forward and is in the locked position, the rear regulating portion 103c is disposed so as to abut against the left side surface of the second right-side locking member 102. The rear regulating portion 103c is configured similarly to the front regulating portion 103b, and is a portion that puts the second right-side locking member 102 in the locked state and abuts against the second right-side locking member 102 in the locked state to regulate the retreat of the second right-side locking member 102.

[0117] As shown in Fig. 16, when the right sliding member 103 slides backward and is in the unlocked position, the rear end portion thereof protrudes rearward from the rear end surface of the right seating frame 91. On the other hand, when the right sliding member 103 is in the unlocked position, the front end portion thereof is located within the right seating frame 91. Then, as shown in Fig. 19, when the right sliding member 103 slides forward and is in the locked position, the front end portion of the right sliding member 103 protrudes forward from the front end surface of the right seating frame 91.

[0118] The front end of the right slide member 103 is adapted to be locked to the right side frame 30. As shown in Fig. 10, a right insertion hole (insertion portion) 34f serving as a locking hole is formed on the front side of the upper frame portion 31 of the right side frame 30. This right insertion hole 34f is formed in a portion of the upper frame portion 31 corresponding to the front end of the right slide member 103, and opens to the front engagement surface 34a of the front accommodating recess 34. Therefore, the front end of the right slide member 103 in the locked position is inserted into the right insertion hole 34f through the opening of the front engagement surface 34a.

[0119] The right side slide member 103 in the unlocked position is adapted to be switched to the locked position in conjunction with the mounting operation of the seat 3 to the wheelchair body 2. To be more specific, as shown in FIG. 16, the seat back frame 92 is folded before the seat 3 is mounted to the wheelchair body 2. Thereafter, as shown in FIG. 18, the seat frame 7 is placed on the left side frame 20 and the right side frame 30 of the wheelchair body 2 and fitted together. Next, as shown in FIG. 19, when the seat back frame 92 is rotated to the upright state, the right pressing portion 84e comes into contact with the rear end of the right side slide member 103 and pushes the right side slide member 103 forward with a force equal to or greater than a predetermined force. As a result, the right side slide member 103 is switched from the unlocked position to the locked position in conjunction with the operation of the seat back frame 92 to the upright state, and the first right lock member 101 and the second right lock member 102 are locked and engaged with the recesses 34e and 35e. At the same time, the front end of the right-side slide member 103 is inserted into the right-side insertion hole 34f through the opening in the front engagement surface 34a and engaged, thereby preventing the front end of the right-side seating frame 91 from floating up when the wheelchair user is seated.

[0120] As shown in FIG. 3, the left seating frame 90, like the right seating frame 91, is provided with a first left locking member 111, a second left locking member 112, one left slide member 113, and a left coil spring (biasing member) 114.

[0121] The first left locking member 111 is provided on the front side of the left side surface of the left seating frame 90 and is positioned so as to overlap, in side view, with a recess 24e (shown in FIG. 7) formed in the front accommodation recess 24 of the left side frame 20. In side view, the first left locking member 111 and the front cross beam 97 overlap.

[0122] 3 is provided on the rear side of the left side surface of the left seating frame 90 and is positioned so as to overlap with a recess 25e (shown in FIG. 7) formed in the rear accommodation recess 25 of the left side frame 20 in a side view. The second left locking member 112 and the rear cross beam 98 overlap in a side view.

[0123] The vertical center portion of the first left locking member 111 protrudes from the left side surface of the left seating frame 90 toward the left side of the left seating frame 90 and enters the recessed portion 24e. When the center portion of the first left locking member 111 enters the recessed portion 24e, it comes into contact with the inner surface of the recessed portion 24e and is locked. Also, the vertical center portion of the second left locking member 112 enters and is locked in the recessed portion 25e.

[0124] The left slide member 113 and the left coil spring 114 are housed in the left seating frame 90. The right slide member 103 is disposed to the right of the first left locking member 111 and the second left locking member 112, and is held by the left seating frame 90 so as to be slidable in the front-rear direction. The left slide member 113 is slidable between a locked position where the first left locking member 111 and the second left locking member 112 are locked, and an unlocked position where the first left locking member 111 and the second left locking member 112 are unlocked.

[0125] A spring abutment portion 113a against which the rear end portion of the left coil spring 114 abuts is formed in a rear portion of the left slide member 113. A front restricting portion 113b that abuts against the first left locking member 111 is provided in a front portion of the left slide member 113, and a rear restricting portion 113c that abuts against the second left locking member 112 is provided in a portion of the left slide member 113 rearward of the spring abutment portion 113a.

[0126] When the left sliding member 113 is in the unlocked position, the rear end of the left sliding member 113 protrudes rearward from the rear end surface of the left seating frame 90. Meanwhile, when the left sliding member 113 is in the unlocked position, the front end of the left sliding member 113 is located inside the left seating frame 90. Then, when the left sliding member 113 slides forward to the locked position, the front end of the left sliding member 113 protrudes forward from the front end surface of the left seating frame 90.

[0127] The front end of the left slide member 113 is adapted to be engaged with the left side frame 20. Although not shown, a left insertion hole (insertion portion) is formed in the front side of the upper frame portion 21 of the left side frame 20. This left insertion hole is formed in a portion of the upper frame portion 21 that corresponds to the front end of the left slide member 113, and opens into the front engagement surface 24a of the front accommodating recess 24. Therefore, the front end of the left slide member 113 in the locked position is inserted into the left insertion hole through the opening in the front engagement surface 24a.

[0128] The left side slide member 113, which is in the unlocked position, can also be switched to the locked position in conjunction with the mounting operation of the seat 3 to the wheelchair body 2. When the seat back frame 92 is in the upright position, the left side pressing portion 83e comes into contact with the rear end of the left side slide member 113 and pushes the left side slide member 113 forward with a force equal to or greater than a predetermined value. This causes the first left side lock member 111 and the second left side lock member 112 to enter the locked state and engage with the recesses 24e, 25e. At the same time, the front end of the left side slide member 113 is inserted into and engaged with the left side insertion hole, so that the front end of the left side seating frame 90 can be prevented from lifting up when the wheelchair user sits down.

[0129] (Variation 1) 20 to 22 are related to the first modified embodiment. This modified embodiment is different from the above embodiment in that the lifting member 120 is used when switching the right slide member 103 from the unlocked position to the locked position. That is, the rear end of the right slide member 103 is provided with a sliding surface 103e housed in the right seating frame 91, while the lifting member 120 that slides against the sliding surface 103e is held in the right seating frame 91 so as to be liftable. The sliding surface 103e is inclined so as to be positioned higher toward the rear. The upper surface of the lifting member 120 is a surface that slides against the sliding surface 103e and is inclined so as to be positioned higher toward the rear. The lower side of the lifting member 120 is formed with a pin portion 120a that penetrates the right seating frame 91 and protrudes downward. The right seating frame 91 also houses a spring 121 that constantly urges the lifting member 120 downward.

[0130] In this modified example 1, as shown in Fig. 20, when the seat 3 is removed from the wheelchair body 2, the lifting member 120 is positioned at the lower end position by the biasing force of the spring 121, and the right slide member 103 is retracted to the unlocked position. When the seat 3 is attached to the wheelchair body 2 from this state, the pin portion 120a of the lifting member 120 is pushed upward by the inner surface of the rear storage recess 35 of the upper frame portion 31, as shown in Fig. 21. This causes the lifting member 120 to rise against the biasing force of the spring 121. When the lifting member 120 rises, the upper surface of the lifting member 120 comes into sliding contact with the sliding surface 103e of the right slide member 103, and since the sliding surface 103e is inclined so as to be positioned higher as it goes toward the rear side, a force directed forward acts on the right slide member 103, and the right slide member 103 is switched to the locked position. That is, the right side slide member 103, which is in the unlocked position, is switched to the locked position in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2. In addition, by switching the right side slide member 103 to the locked position, the first right side lock member 101 and the second right side lock member 102 are also locked. The left side can be configured in the same way.

[0131] (Variation 2) 23 to 25 show a second modified example of the embodiment. The second modified example is different from the above embodiment in that a cam 130 is used to switch the right slide member 103 from the unlocked position to the locked position. That is, the rear end of the right slide member 103 is accommodated in the right seating frame 91, and a cam 130 that abuts against the rear end is provided on the rear side of the right seating frame 91. The cam 130 is provided on the right seating frame 91 so as to be rotatable around a shaft 130a extending in the left-right direction. A rear piece 130b of the cam 130 protrudes rearward from the right seating frame 91. On the other hand, a front piece 130c of the cam 130 extends above the shaft 130a and is disposed so as to abut against the rear end of the right slide member 103.

[0132] In this modified example 2, as shown in Fig. 23, when the seat 3 is removed from the wheelchair body 2, the right slide member 103 is held in the unlocked position by the urging force of the right coil spring 104, and the front piece 130c of the cam 130 is pushed backward by the rear end of the right slide member 103, so that the cam 130 is held in the position shown in the figure. When the seat 3 is attached to the wheelchair body 2 from this state, the rear piece 130b of the cam 130 is pushed forward by the inner surface of the rear storage recess 35 of the upper frame part 31, so that the cam 130 tries to rotate forward. The rotation force of the cam 130 is transmitted from the front piece 130c to the rear end of the right slide member 103, so that the right slide member 103 is switched to the locked position as shown in Fig. 24. That is, the right slide member 103 in the unlocked position is switched to the locked position in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2. Furthermore, by switching the right slide member 103 to the lock position, the first right lock member 101 and the second right lock member 102 are also locked. The left side can be configured in the same way.

[0133] (Variation 3) 26 to 28 relate to the third modification of the embodiment. The third modification is different from the above embodiment in that the inner surface of the rear storage recess 35 of the upper frame part 31 is used when switching the right slide member 103 from the unlocked position to the locked position. That is, as shown in FIG. 27, when the seat 3 is attached to the wheelchair body 2, the rear end of the right slide member 103 abuts against the rear engagement surface 35b of the rear storage recess 35 of the upper frame part 31. As a result, the right slide member 103 is pushed forward by the rear engagement surface 35b and switched to the locked position. That is, the right slide member 103 from the unlocked position is switched to the locked position in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2.

[0134] In the third modification, an operating lever 150 for manually operating the right-side slide member 103 is provided. The operating lever 150 can be provided on the rear side of the right-side slide member 103. A shaft 150a extending in the left-right direction is provided at the lower end of the operating lever 150, and the shaft 150a allows the operating lever 150 to rotate freely relative to the right-side slide member 103. As described above, when the right-side slide member 103 is in the locked position, the first right-side lock member 101 and the second right-side lock member 102 are also in the locked state, and the seat frame 7 cannot be removed. In this modification, the operating lever 150 can be rotated rearward to slide the right-side slide member 103 in the locked position further forward. As a result, the front-side regulating portion 103b and the rear-side regulating portion 103c move forward of the first right-side lock member 101 and the second right-side lock member 102, respectively, so that the first right-side lock member 101 and the second right-side lock member 102 are switched to the unlocked state. In this state, by lifting the seat frame 7 obliquely rearward, the right-side slide member 103 can be removed from the right-side insertion hole 34f, and the seat frame 7 can be removed.

[0135] In addition, in the third modified example, the rear end of the right slide member 103 may be positioned higher than the upper part in the middle in the front-rear direction without providing the operating lever 150. This allows the rear end of the right slide member 103 to be manually operated.

[0136] (Effects of the embodiment) As described above, according to this embodiment, the wheelchair main body 2 can be folded by operating the operating part 74 of the folding mechanism 70 in the vertical direction, so that the folding operation can be performed with one hand without having to pull a part of the wheelchair main body 2 or the drive wheels, etc., thereby improving convenience.

[0137] In addition, since the operating part 74 of the folding mechanism 70 is positioned below the upper ends of the left seating frame 90 and the right seating frame 91 with a specified space therebetween, the operating part 74 does not cause discomfort to the seated wheelchair user, thereby improving the riding comfort.

[0138] In addition, since the operating unit 74 of the folding mechanism 70 is disposed between the drive wheels 10, 11 and the casters 12, 13 in a side view of the vehicle body, it is possible to prevent the casters 12, 13 from sagging when the wheelchair 1 is lifted by holding the operating unit 74. This allows the wheelchair 1 to be easily moved in a lifted state.

[0139] In addition, since it is equipped with a grip portion 75 that extends in the rotation direction of the support arms 51, 61 when switching from the folded state to the unfolded state, the wheelchair body 2 can be unfolded with one hand by utilizing its own weight when unfolding the wheelchair body 2.

[0140] In addition, the front engagement surfaces 24a, 25a, 34a, 35a and the rear engagement surfaces 24b, 25b, 34b, 35b of the storage recesses 24, 25, 34, 35 provided in the side frames 20, 30 of the wheelchair main body 2 are formed to approach each other as they go downward, so that the seat frame 7 can be easily attached and detached from the top of the wheelchair main body 2 and the seat frame 7 can be firmly fixed to the wheelchair main body 2 when installed.

[0141] Furthermore, since the locking members 101, 102, 111, 112 of the seat frame 7 can be engaged with the recessed portions 24e, 25e, 34e, 35e of the wheelchair body 2 in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2, the seat frame 7 can be firmly attached to the wheelchair body 2 with a simple operation.

[0142] Furthermore, since the seat frame 7 can be fixed to the wheelchair body 2 in conjunction with the mounting operation of the seat frame 7 to the wheelchair body 2, simple operation can be achieved.

[0143] The above-described embodiment is merely illustrative in all respects and should not be construed as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention. [Industrial Applicability]

[0144] As described above, the wheelchair according to the present invention can be used when it is carried in, for example, a car. [Explanation of symbols]

[0145] 1. Wheelchair 4 Seat cushion section 7 Seat frame 10, 11 Left drive wheel, right drive wheel 12, 13 Left caster, right caster 20, 30 Left side frame, right side frame 24 Front storage recess (left engagement recess) 24a Front engagement surface 24b Rear engagement surface 25 Rear accommodation recess (left engagement recess) 34 Front accommodation recess (right engagement recess) 34f Insertion hole (insertion part) 35 Rear accommodation recess (right engagement recess) 51 First left support arm 52 Second left support arm 61 First right support arm 62 Second right support arm 70 Folding mechanism 71 Front connecting member 73 Interlocking parts 74 Control section 74a Support shaft (support member) 75 Gripping part 75a 1st grip part 75b 2nd grip part 76 Left driven gear section (first gear section) 77 Right side driven gear section (first gear section) 78 Drive gear section (second gear section) 84d Locking part 84e Pressing part 90, 91 Left seat frame, right seat frame 93 1st left side engagement protrusion 94 Second left side engagement protrusion 95 1st right side engagement protrusion 96 Second right side engagement protrusion 97, 98 Front cross beam, rear cross beam 101 First right locking member 102 Second right locking member 103 Right side slide member 104 Right coil spring (biasing member) 103b Front restriction section 103c Rear restriction section

Claims

1. In a folding wheelchair that wheelchair users can sit on, A left side frame that supports the drive wheel on the left side of the vehicle body; A right side frame that supports the drive wheels on the right side of the vehicle body; a left support arm having a left end portion connected to the left side frame so as to be rotatable about an axis extending in the vertical direction; a right support arm having a right end portion rotatably connected to the right side frame about an axis extending in the vertical direction; a folding mechanism that connects the left support arm and the right support arm so as to be foldable in the left-right direction of a vehicle body; a seat frame having a seating frame supporting a seat cushion portion on which a wheelchair user sits, the folding mechanism includes a left driven gear portion provided at the right end of the left support arm so as to be arranged side by side so as to describe an arc-shaped locus centered on an axis extending in the vertical direction, a right driven gear portion provided at the left end of the right support arm so as to be arranged side by side so as to describe an arc-shaped locus centered on an axis extending in the vertical direction, a connecting member connecting the right end of the left support arm and the left end of the right support arm so as to be rotatable relative to each other about an axis extending in the vertical direction, an operating portion whose base end is supported by the connecting member so as to be rotatable about a support shaft extending in the left-right direction, and a drive gear portion provided at the base end of the operating portion so as to be arranged side by side so as to describe an arc-shaped locus centered on the support shaft, and meshing with the left driven gear portion and the right driven gear portion, The operation unit is switched between a first operation state in which the operation unit stands upward and a second operation state in which the operation unit is tilted down by rotating about the support shaft, the folding mechanism is configured to transmit a rotational force in a folding direction to the left support arm and the right support arm via the drive gear unit, the left driven gear unit, and the right driven gear unit in response to a switching operation of the operation unit from the second operation state to the first operation state, thereby causing the left support arm and the right support arm in the unfolded state to be in a folded state, and to transmit a rotational force in a unfolding direction to the left support arm and the right support arm via the drive gear unit, the left driven gear unit, and the right driven gear unit in response to a switching operation of the operation unit from the first operation state to the second operation state, thereby causing the left support arm and the right support arm in the folded state to be in an unfolded state, A wheelchair characterized in that the operating unit in the second operating state is spaced below the upper end of the seat frame by a predetermined distance or more in a side view.

2. 2. The wheelchair according to claim 1, The seat frame is configured to be detachable from the left side frame and the right side frame, A wheelchair characterized in that an upper end of the operating unit in the first operating state is positioned higher than an upper end of the seat frame.

3. 2. The wheelchair according to claim 1, The wheelchair is characterized in that the operating unit is disposed directly below the seat cushion unit.

4. A wheelchair according to any one of claims 1 to 3, the seating frame includes a left seating frame extending in the front-rear direction of the vehicle body along the left side frame, and a right seating frame extending in the front-rear direction of the vehicle body along the right side frame, The operating unit is disposed between the left seat frame and the right seat frame in a plan view, The wheelchair is characterized in that the seat cushion portion is provided continuously from the left seating frame to the right seating frame.

Images