JP7578005B2 - wheelchair - Google Patents

Description

The present invention relates to a foldable wheelchair that is configured to be foldable.

Conventionally, folding wheelchairs that are configured to be folded when not in use have been known (see, for example, Patent Document 1). The wheelchair in Patent Document 1 has left and right side frames on which the drive wheels are supported, and support arms and cross members that connect the left and right side frames. When in use, the support arms and cross members are swung in a direction that widens the gap 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 gap between the left and right side frames to swing the support arms and cross members to keep the wheelchair in a folded state.

JP 2016-198334 A

Foldable wheelchairs, such as the wheelchair in Patent Document 1, are widely used because folding them up when not in use to make them compact allows them to take up less space when stored.

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 that narrows 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 in addition to the side frames, but this method may also be difficult for some wheelchair users. If the wheelchair user is unable to fold the wheelchair by themselves, they need help, such as being supported by people around them.

In addition, wheelchair users who are able to drive a car may drive the car alone to increase their freedom of movement. In this case, after transferring from their wheelchair to the driver's seat of the car, the wheelchair user must reach out to the wheelchair outside the car in a state where it is difficult for them to move, and fold the wheelchair. 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 places a burden on the wheelchair user. The same applies when a wheelchair user rides in the passenger seat of a car.

The present invention was made in consideration of these points, and its purpose is to increase convenience by allowing the folding operation to be performed with one hand, without having to pull the wheelchair by holding a part of the wheelchair body or the drive wheels, etc.

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, and a folding mechanism that connects the left support arm and the right support arm so that they can be folded in the left-right direction of the vehicle body. The folding mechanism includes an operating unit whose operating direction is the up-down direction, and is configured to change the left support arm and the right support arm from one of a folded state and an unfolded state to the other by operating the operating unit.

With this configuration, when the left and right support arms are deployed, the distance between the left and right side frames increases, the wheelchair is deployed, and the wheelchair user can sit down. On the other hand, when the left and right support arms are folded, the distance between the left and right side frames decreases, the wheelchair is folded, and the wheelchair becomes compact.

When changing the left and right support arms from a folded state to an unfolded state, or from an unfolded state to a folded state, it is only necessary to operate the operation unit of the folding mechanism in the vertical direction. In other words, when the left and right support arms are unfolded, if the wheelchair user operates the operation unit in the vertical direction, the left and right support arms will be folded, so the wheelchair user can perform the folding operation with one hand without having to pull the wheelchair by holding the arm support or drive wheel as in the conventional example. In particular, when the wheelchair user sits in the driver's seat or passenger seat of a car and then folds the wheelchair outside the car and loads it into the car, the wheelchair can be folded simply by operating the operation unit in the vertical direction, which increases convenience.

In a second aspect of the present disclosure, the folding mechanism includes a support member that supports the operating unit in a manner that allows the operating unit to be switched 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 the left support arm and the right support arm can be changed from an unfolded state to a folded state by switching the operating unit from the second operating state to the first operating state.

With this configuration, when folding a wheelchair from an unfolded state, the folding operation can be easily performed by simply operating the tilted operating unit upward to raise it up. In addition, after folding the wheelchair, the wheelchair can be easily lifted and moved while still holding the operating unit. This further increases convenience for wheelchair users, especially those seated in a vehicle.

In a third aspect of the present disclosure, the folding mechanism can change the left support arm and the right support arm from a folded state to an unfolded state by switching the operation unit from the first operation state to the second operation state.

With this configuration, when unfolding the wheelchair from its folded state, all that is required is to operate the upright operating part downward and tilt it over. This makes it easy for a wheelchair user, for example, to unfold the wheelchair while remaining seated in the vehicle.

The fourth aspect of the present disclosure is that the operating unit in the first operating state can be switched to the second operating state by tilting the operating unit toward the rear of the vehicle body.

The fifth aspect of the present disclosure is that the operating unit in the second operating state can be switched to the first operating state by lifting the operating unit toward the front of the vehicle body.

That is, when a wheelchair user gets into the driver's seat or passenger seat of a car, the wheelchair is placed to the side of the seat and the wheelchair user moves to the seat alone, and then the wheelchair is folded. At this time, when viewed from the wheelchair user seated in the seat, the wheelchair may be positioned slightly behind the wheelchair user rather than directly to the side. In this case, as in this configuration, the wheelchair can be folded by pulling the operating unit toward the front of the wheelchair body, improving operability.

In a sixth aspect of the present disclosure, the wheelchair is provided with a seat frame that supports a seat cushion portion on which a wheelchair user sits and is configured to be detachable from the left side frame and the right side frame.

With this configuration, the seat frame can be removed from the left and right side frames 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 that needs to be lifted in one go when loading the wheelchair into the car, making the task of loading the wheelchair into the car easier.

In a seventh aspect of the present disclosure, the folding mechanism is provided between the left side frame and the right side frame, and the operating portion can be formed, for example, in a ring shape.

With this configuration, the wheelchair can be easily lifted by placing your fingers through the operating part.

As explained above, the wheelchair can be folded by operating the operating unit in the vertical direction, so the folding operation can be performed with one hand without having to pull the wheelchair by holding part of the wheelchair body or the drive wheels, etc., which increases convenience.

1 is a perspective view of a wheelchair according to an embodiment of the present invention, seen from above. FIG. 2 is a perspective view showing the wheelchair body with the seat removed. FIG. FIG. 1 is a left side view of a wheelchair according to an embodiment of the present invention. FIG. 2 is a perspective view of the folded wheelchair body seen from above. FIG. 2 is a plan view of the folded wheelchair body. FIG. FIG. 4 is a perspective view of the rear side of the right side frame as viewed from the upper left. FIG. 4 is a perspective view of the front side of the right side frame as viewed from the upper left. FIG. FIG. 2 is a plan view of the support arm and folding mechanism. FIG. 2 is a perspective view of the support arm and the folding mechanism from the upper left. FIG. 4 is a plan view of the first left support arm. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 11. 1 is an enlarged perspective view of the vicinity of an operating unit of the folding mechanism as viewed from the upper right. FIG. 2 is a partial cross-sectional view showing the seat before it is attached to the wheelchair body. FIG. FIG. 17 is a view equivalent to FIG. 16 showing the seat placed on the wheelchair body before the seat back frame is raised. FIG. 17 is a view equivalent to FIG. 16, showing a state in which the seat back frame is raised. FIG. 16 according to a first modified example of the embodiment. FIG. 19 is a view corresponding to FIG. 18 according to a first modified example of the embodiment. FIG. 20 is a view corresponding to FIG. 19 according to a first modified example of the embodiment. FIG. 16 is a view according to a second modified example of the embodiment. FIG. 18 is a view according to a second modified example of the embodiment. FIG. 20 is a view corresponding to FIG. 19 according to a second modified example of the embodiment. FIG. 16 is a view according to a third modified example of the embodiment. FIG. 20 is a view corresponding to FIG. 19 according to a third modified example of the embodiment. FIG. 13 is a diagram showing a case where the lock is released according to the third modification of the embodiment. 1 is a plan view of a wheelchair according to an embodiment of the present invention. FIG. 1 is a front view of a wheelchair according to an embodiment of the present invention. FIG. 2 is a bottom view of the wheelchair according to the embodiment of the present invention. FIG. 2 is a rear view of the wheelchair according to the embodiment of the present invention.

The following describes in detail an embodiment of the present invention with reference to the drawings. Note that the following description of the preferred embodiment is essentially merely an example and is not intended to limit the present invention, its applications, or its uses.

Figure 1 is a perspective view of a wheelchair 1 according to an embodiment of the present invention, seen from diagonally above and ahead. As shown in Figure 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 Figure 3. Figure 4 is a left side view of the wheelchair 1 with the seat 3 attached. Furthermore, with the seat 3 removed, the wheelchair body 2 is configured to be foldable, as shown in Figures 5 and 6, and therefore the wheelchair 1 according to this embodiment is a foldable wheelchair.

Note that while FIG. 2 shows the seat cushion portion 4 and back cushion portion 5 of the seat 3, FIG. 1 and FIG. 4 do not show the seat cushion portion 4 and back cushion portion 5. Also, FIG. 3 shows only the outer shapes of the seat cushion portion 4 and back cushion portion 5 with imaginary lines. The specific configuration of the seat 3 will be described later.

In the description of this embodiment, the direction of travel of the wheelchair 1 when moving forward is simply referred to as the front, and the front of the wheelchair 1 corresponds to the front of the wheelchair user (not shown) seated in the wheelchair 1. The direction of travel of the wheelchair 1 when moving backward is simply referred to as the 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. 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 the left. 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 the right. The left-to-right direction of the wheelchair 1 is also the width direction of the body. 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.

(Configuration of 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 can also be called rear drive wheels because they are provided at the rear 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 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.

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 located on the front side of the wheelchair body 2, so they can also be called front wheels for changing the direction of travel.

As shown in Figure 7, the left side frame 20 comprises an upper frame portion 21 extending in the front-rear direction, and a caster support portion 22. Figure 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 moves 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 together.

The rear end of the upper frame portion 21 is formed with an axle insertion hole 21a into which the right side of the axle 10d of the left driving wheel 10 is inserted and fixed. 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 supported rotatably around an axis extending in the left-right direction relative to the left side frame 20.

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 in 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-to-rear direction, which reduces the weight of the left side frame 20. The through hole 21c can be long in the front-to-rear direction.

The rear end of the upper frame portion 21 is provided with a rear recess 21d that is recessed toward the front. The rear recess 21d is a portion that engages with a part of the seat 3, as described below.

A storage recess 23 is formed on the right side of the upper frame portion 21 to accommodate the left seating frame 90 (described later) of the seat 3. The storage recess 23 is open upward, making it possible to store the seating frame 90 in the storage recess 23 from above. The storage recess 23 also opens to the right, i.e., to the inside in the width direction of the vehicle body, making it possible to see the inner surface of the storage recess 23 from the right.

The storage recess 23 is made up of three sections. That is, the front section of the storage recess 23 is the front storage recess (left side engagement recess) 24, and the rear section of the storage recess 23 is the rear storage recess (left side engagement recess) 25. Furthermore, the section of the storage recess 23 between the front storage recess 24 and the rear storage recess 25 is the intermediate storage recess 26. A through hole 21c is located between the front storage recess 24 and the rear storage recess 25. Furthermore, a through hole 21c is located below the intermediate storage recess 26.

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

The surfaces located on the front and rear sides of the inner surface of the front storage 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 as they go downward. In other words, the front engagement surface 24a is composed of an inclined surface that is located further back as it goes downward, and the rear engagement surface 24b is composed of an inclined surface that is 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 separated from each other in the front-to-rear direction.

Also, as shown in FIG. 8, the front engagement surface 24a and the rear engagement surface 24b are formed so that they 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 that it is positioned further back toward the right, and the rear engagement surface 24b extends so that it is 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 fore-and-aft direction, and this portion opens the front storage recess 24 to the right.

The bottom surface 24c of the front storage recess 24 extends from the lower end of the front engagement surface 24a to the lower end of the rear engagement surface 24b. Also, as shown in FIG. 7, the left side surface 24d of the inner surface of the front storage 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 locking portion described later, 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-to-rear direction. The shape of the recess 24e is not particularly limited, but in this embodiment, the dimension in the front-to-rear direction is set longer than the dimension in the up-to-down direction when viewed from the right side. Also, the depth (horizontal dimension) of the recess 24e is set so that it is deepest at the vertical center.

The rear storage recess 25 is configured in the same manner as the front storage recess 24. The front engagement surface 25a and the rear engagement surface 25b of the rear storage 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 storage recess 24. Furthermore, as shown in FIG. 8, they are formed so as to approach each other toward the right. Also, as shown in FIG. 7, the bottom surface 25c of the rear storage recess 25 is located directly above the axle insertion hole 21a. Also, on the left side surface 25d of the inner surface of the rear storage recess 25, a recess 25e is formed as a locked portion, recessed to the left. The front recess 24e and the rear recess 25e may have the same shape or different shapes.

As shown in FIG. 7, the caster support portion 22 extends diagonally downward from the middle portion of the upper frame portion 21 in the front-rear direction toward the front. As shown in FIG. 8, the caster support portion 22 curves so that it is positioned to the left, i.e., on the outside in the width direction of the vehicle body, as it goes downward. As shown in FIG. 4, the lower end portion of the caster support portion 22 is located a predetermined distance or more forward from the left driving wheel 10, and the left caster 12 is attached to this lower end portion so as to be rotatable around a center line extending in the vertical direction. The caster 12 is located directly below the front protrusion 21b of the upper frame portion 21.

As shown in FIG. 2 etc., the right side frame 30 has a symmetrical structure 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 around 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 of the upper frame portion 31.

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-to-rear direction. A rear recess 31d (shown in FIG. 9) is provided at the rear end of the upper frame portion 31 so as to be recessed forward. Note that FIG. 9 also shows a portion of the right angle change portion 84, which is a component that constitutes part of the seat 3, and this right angle change portion 84 hides part of the rear end of the upper frame portion 31.

As shown in FIG. 2, a storage recess 33 is formed on the left side of the upper frame portion 31 to accommodate the right seating frame 91 (described later) of the seat 3. 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.

As shown in Figures 9 and 10, the storage recess 33 has a front storage recess (right-side engagement recess) 34, a rear storage recess (right-side engagement recess) 35, and an intermediate storage recess 36. As shown in Figure 10, the front engagement surface 34a and the rear engagement surface 34b of the front storage recess 34 extend in the vertical direction and are formed so as to approach each other downwards and to approach each other leftwards. A bottom surface 34c and a right side surface 34d are formed on the inner surface of the front storage 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.

As shown in FIG. 9, the rear storage recess 35 is configured similarly to the front storage recess 34, with the front engagement surface 35a and the rear engagement surface 35b extending vertically and being closer to each other as they go downward and to the right. The bottom surface 35c of the rear storage recess 35 is located directly above the axle insertion hole 31a. The right side surface 35d of the rear storage recess 35 has a recessed portion 35e recessed to the right as a latching portion.

As shown in FIG. 1 etc., the caster support part 32 extends diagonally downward from the middle part of the upper frame part 31 in the front-rear direction toward the front, and curves so that it is positioned to the right as it goes downward. The right caster 13 is attached to the lower end of the caster support part 32 so as to be able to rotate around a center line extending in the vertical direction.

(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 mounting 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 mounting 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 mounting arm 41 and the left end of the right mounting arm 42 to each other. The center line of rotation extends in the front-rear direction. The left mounting arm 41 is provided with a left plate 41a on which the left foot is placed, and the right mounting arm 42 is provided with a right plate 42a on which the right foot is placed.

As shown in Figures 1 and 2, when the wheelchair body 2 is in the unfolded state, the left mounting arm 41 and the right mounting arm 42 are in a position in which they extend horizontally. On the other hand, as shown in Figure 5, when the wheelchair 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 in which they extend substantially in the vertical direction, and the connecting plate 43 is positioned on top. In other words, the left mounting arm 41 and the right mounting arm 42 are able to rotate relatively to each other so as not to impede the folding operation of the wheelchair body 2.

(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 more 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.

(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. Note that 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.

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

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 the lower part of the upper frame part 31 of the right side frame 30, which is forward of the center of the front-rear direction, 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 the lower part of the upper frame part 31 of the right side frame 30, which is rearward of the center of the front-rear direction, 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, and 62a are tilted slightly forward or backward, for example.

For example, as shown in FIG. 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 similarly inclined. 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.

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, which is the right end of the first left support arm 51, extends to the center in the left-right direction between the left side frame 20 and the right side frame 30, and the tip, which is the left end of the first right support arm 61, also extends to the center in the left-right direction between the left side frame 20 and the right side frame 30.

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, and 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 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 limited thereto, and the first left support arm 51 and the first right support arm 61 may not be parallel, and may be arranged so that the distance between them increases toward the base ends of the support arms 51 and 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 40 rotate upward, and the folding operation of the foot rest 40 is performed at the same time.

The left support arms 51, 52 and the right support arms 61, 62 are not allowed to rotate forward from the deployed state. That is, as shown in FIG. 11, when the first left support arm 51 tries to rotate forward from the deployed state, the edge 51b on the base end side of the first left support arm 51 abuts against the upper frame portion 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 the second right support arm 62 is also prevented from rotating forward by the edge 62b. The configuration for preventing 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.

(Folding mechanism)
Next, the configuration of the folding mechanism 70 shown in Figures 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 section 74, a gripping section 75, a left driven gear section (first gear section) 76, a right driven gear section (first gear section) 77, and a driving gear section (second gear section) 78. Only one of the left driven gear section 76 and the right driven gear section 77 may be provided. Below, each member constituting the folding mechanism 70 will be described in detail.

(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.

Similarly, as shown in FIG. 11, the multiple teeth that make up the right driven gear portion 77 are arranged to draw an arc-shaped trajectory centered on the support shaft 61c that is inserted into the tip of the first right support arm 61 and is prevented from falling out. Therefore, the center line of rotation of the right driven gear portion 77 also extends in the vertical direction. The center lines of rotation of the left driven gear portion 76 and the right driven gear portion 77 are parallel to the connecting shaft 51a.

The left driven gear portion 76 and the right driven gear portion 77 are arranged at a predetermined distance in the left-right direction. The number of teeth of the left driven gear portion 76 is the same as the number of teeth of the right driven gear portion 77.

(Connecting member)
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.

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 around the support shaft 72a, and the second right support arm 62 is rotatable around 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.

A ring-shaped portion 72d is provided at the rear 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 a different shape.

(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. On the other hand, 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.

(Operation section and drive gear section)
The operation unit 74 is a member for a person (operator) performing the folding operation, such as a wheelchair user or a caregiver, 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.

The portion of the operating unit 74 that is radially distant from the support shaft 74a is formed in a ring shape. This allows the operator to insert their 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 that includes a portion that extends radially from the support shaft 74a and a portion that extends parallel to the support shaft 74a.

As shown in FIG. 14, the drive gear unit 78 is integrally provided at the base end of the operating unit 74, so that the drive gear unit 78 and the base end of the operating unit 74 do not rotate relative to each other. The teeth constituting the drive gear unit 78 are arranged so as to draw an arc-shaped trajectory centered on the support shaft 74a at the base end of the operating unit 74. Therefore, the rotation center line of the drive gear unit 78 extends in the left-right direction. Since the operating unit 74 and the drive gear unit 78 are integrated, the drive 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 drive 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 drive gear unit 78.

The support shaft 74a is positioned 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 operating unit 74 are positioned above the first left support arm 51 and the first right support arm 61. When operating the operating unit 74, it is held in the hands from above, but because the operating unit 74 is positioned 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 operating unit 74 in the hands, resulting in good operability.

The width of the teeth of the drive gear section 78 (the dimension in the left-right direction) is set so that it reaches from the left driven gear section 76 to the right driven gear section 77. This allows the teeth of the drive gear section 78 to mesh with the teeth of both the left driven gear section 76 and the right driven gear section 77. In other words, one drive gear section 78 can drive two driven gear sections 76, 77, which reduces the number of parts. In addition, the timing at which the driven gear sections 76, 77 start to rotate and the rotation speed can be made the same.

The rotation center line of the drive gear unit 78 extends in the left-right direction, while the rotation center lines of the left driven gear unit 76 and the right driven gear unit 77 extend in the up-down direction. Even though the rotation center lines are perpendicular to each other in this manner, by positioning the rotation center line of the drive gear unit 78 above the left driven gear unit 76 and the right driven gear unit 77, smooth transmission of force is possible.

(Folding and unfolding operations using the operation 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.

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.

To explain in more detail, when switching the operating unit 74 from a non-standing state to an 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, operating the operating unit 74 in a predetermined direction causes the driving gear unit 78 to rotate forward around the support shaft 74a. When the driving gear unit 78 rotates, a rotational force is transmitted to the left side driven gear unit 76 and the right side driven gear unit 77 that are meshed with the driving gear unit 78, and the left side driven gear unit 76 and the right side driven gear unit 77 attempt to rotate around the center line in the vertical direction. At this time, the base end of the first left support arm 51, which is integrally provided with the left driven gear portion 76, 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, which is integrally provided with the right driven gear portion 77, can rotate with respect to the right side frame 30 by the support shaft 61a. Furthermore, the tip end of the first left support arm 51 and the tip end of the first right support arm 61 can both rotate 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 around the support shaft 51a, and the first right support arm 61 rotates rearward around 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.

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 an interlocking member 73, so that the second left support arm 52 and the second right support arm 62 also rotate around 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.

(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 a 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.

In response to this, the position of the operating unit 74 has been carefully considered in this embodiment. 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 center line of rotation 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 of the wheelchair body 2 naturally tilts lower than the front. This prevents the casters 12, 13 from sagging.

(Grip portion)
As shown in Fig. 11 and Fig. 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.

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.

The grip 75 can be used when changing the wheelchair body 2 from a folded state to an 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 part 75, there is no need to operate the operating part 74.

The shape and structure of the gripping portion 75 are not particularly limited, but in this embodiment, the gripping portion 75 is composed of multiple parts extending in different directions. Specifically, the gripping portion 75 has a first gripping portion 75a that extends 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 that extends in the left-right direction of the vehicle body from the tip of the first gripping portion 75a. The second gripping portion 75b may extend in both 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.

(Seat 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 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 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 body 2. The operation portion 74 and the grip 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.

As shown by the phantom 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-to-rear direction, and is the section that constitutes the 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, mesh-like materials, various elastic materials, and foam materials, and the like, and the material can be configured to elastically deform downward when a wheelchair user sits on it.

When the seat 3 is attached to the wheelchair body 2, the seat cushion section 4 is positioned above the operating section 74 of the folding mechanism 70. In other words, the operating section 74 is positioned 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 vertically spaced apart from each other, with a space being formed between them. This 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.

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 a predetermined distance or more. As a result, the operating unit 74 in a non-standing state in side view is spaced downward from 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.

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. In a side view, the operating unit 74 is positioned at a predetermined distance or more below the upper ends of the seating frames 90, 91 that support the seat cushion portion 4, so that the operating unit 74 does not come into contact with the sunken seat cushion portion 4. As a result, the operating 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, so the wheelchair user does not feel uncomfortable and the ride is comfortable.

The heavier the wheelchair user is, the more the seat cushion section 4 sinks when the wheelchair user sits on it. However, since the operating section 74 is positioned at a predetermined distance or more below the upper end 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 amount of sinking of the seat cushion section 4 at this time can be called the maximum sinking amount. Even when the amount of sinking 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. The amount of sinking may vary depending on the material and structure of the seat cushion part 4, so the above-mentioned specified distance may be changed depending on the material and structure of the seat cushion part 4.

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

When the seat 3 is attached to the wheelchair body 2, the gripping portion 75 is positioned below the seat cushion portion 4. This makes the gripping portion 75 hidden by the seat cushion portion 4, making it difficult for the wheelchair user or caregiver to grab the gripping portion 75 by mistake. On the other hand, when the wheelchair body 2 is folded and held, the seat 3 is removed, so the gripping portion 75 is visible from above and can be easily grasped.

(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.

As shown in FIG. 3, the front side of the left seat frame 90 is provided with a first left engagement protrusion 93 that protrudes downward. The rear side of the left seat frame 90 is provided with a second left engagement protrusion 94. The front-rear distance between the first left engagement protrusion 93 and the second left engagement protrusion 94 is the same as the front-rear distance between the front storage recess 24 and the rear storage recess 25 (shown in FIG. 7) formed in the left side frame 20. When attaching the seat 3, the first left engagement protrusion 93 and the second left engagement protrusion 94 are positioned 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 engagement protrusion 93 and the second left engagement protrusion 94 are inserted into the front storage recess 24 and the rear storage recess 25 from above and engaged. In addition, 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 the intermediate accommodation recess 26 formed in the left side frame 20.

The first left engaging protrusion 93 is hollow, and the hollow portion is open to the left. The front surface 93a and rear surface 93b, which are 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 rear engaging surface 24b of the front storage recess 24. As a result, the front-to-rear dimension of the first left engaging protrusion 93 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 storage recess 24.

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

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, similar to the left seating frame 90. The distance between the first right engagement protrusion 95 and the second right engagement protrusion 96 in the front-rear direction is the same as 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, the portion between the first right engagement protrusion 95 and the second right engagement protrusion 96 in the right seating frame 91 is accommodated in the intermediate storage recess 36 formed in the right side frame 30.

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

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

As configured above, 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 installation operation easy. During installation, 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.

The left side engaging protrusions 93, 94 and the right side engaging protrusions 95, 96 can be inserted into the left side storage recesses 24, 25 and the right side storage recesses 34, 35 and engaged with each other to fit the seat frame 7 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 side storage recesses 24, 25 and the front engaging surfaces 34a, 35a and the rear engaging surfaces 34b, 35b of the right side storage recesses 34, 35 are formed so that they approach each other as they go downward, so that the seat frame 7 can be easily aligned during installation without visually checking the engaging protrusions 93 to 96 or the storage recesses 24, 25, 34, 35. In addition, the seat frame 7 can be easily removed by simply lifting it up.

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 pushed 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, fitting securely 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, fitting securely into the right storage recesses 34, 35.

The seat frame 7 includes a front cross beam 97 and a rear cross beam 98 that extend 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 engaging protrusion 93 to the left side of the first right engaging protrusion 95, and is a portion that connects the first left engaging protrusion 93 and the first right engaging protrusion 95. The rear cross beam 98 extends from the right side of the second left engaging protrusion 94 to the left side of the second right engaging protrusion 96, and is a portion that connects the second left engaging protrusion 94 and the second right engaging 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 molded using the above-mentioned CFRP or the like, but this is not limited thereto, and they may be formed of separate members and then joined together to be integrated.

Providing the front cross beam 97 and 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, the effect of improving the rigidity of the wheelchair body 2 becomes even more remarkable.

(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.

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 that extends forward and are positioned above the seat cushion section 4. This allows the seat 3 to be made compact.

A conventionally known structure can be applied as the folding structure of the seatback frame 92. In this embodiment, the left bar 80 has a left angle change section 83. The left angle change section 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 section 84. The right angle change section 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.

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 rotatably attached 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 spaced apart from each other in the circumferential direction of the rotation center line of the seatback frame 92. For example, the positions of the first and second through holes are set so that when the lock pin 84c is inserted into the first through hole of the rotating member 84b and the lock hole of the fixed member 84a, the seat back frame 92 can be held in an upright position, while when the lock pin 84c is inserted into the second through hole of the rotating member 84b and the lock hole of the fixed member 84a, the seat back frame 92 can be held in a folded position.

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.

The rotating member 83b of the left angle change unit 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 position. Similarly, the rotating member 84b of the right angle change unit 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 position. When the seatback frame 92 is folded, the left locking portion 83d and the right locking portion 84d move upward and come out of the rear recess 21d of the left side frame 20 and the rear recess 31d of the right side frame 30.

In addition, the rotating member 83b of the left angle change unit 83 is provided with a left pressing portion 83e that presses the left slide member 113 (described later) to the 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. In addition, the rotating member 84b of the right angle change unit 84 is provided with a right pressing portion 84e that presses the right slide member 103 (shown in FIG. 17, etc.) (described later) to the 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. 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 forward with a force equal to or greater than a predetermined value.

(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.

The first right 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 with the recessed portion 34e (shown in FIG. 10) formed in the front storage recess 34 of the right side frame 30 in a side view. In a side view, the first right locking member 101 and the front cross beam 97 overlap.

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 the recessed portion 35e (shown in FIG. 9) formed in the rear storage recess 35 of the right side frame 30 in a side view. In a side view, the second right-side locking member 102 and the rear cross beam 98 overlap.

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 greater force, the center part of the first right locking member 101 enters the recessed part 34e while maintaining a state in which it protrudes from the right side surface of the right seating frame 91 to the right side of the right seating frame 91. In this way, the first right locking member 101 is formed. 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 right side frame 30 has a recess 34e as a locked portion in the portion corresponding to the first right locking member 101, so the locked state can be achieved simply by forming the first right locking member 101 into the shape described above.

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

The second right-side locking member 102, like the first right-side locking member 101, has a fixed end at the bottom and a free end at the top. The center of the second right-side locking member 102 enters and engages in the recess 35e. On the other hand, when the second right-side locking member 102 is in an unlocked state, the center of the second right-side locking member 102 can come out of the recess 35e.

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 that holds the first right lock member 101 and the second right lock member 102 in a locked state, and an unlocked position that holds the first right lock member 101 and the second right lock member 102 in an unlocked state. As a result, the first right lock member 101 and the second right lock member 102 can be switched between a locked state and an unlocked state by the single right slide member 103.

That is, the length of the right slide member 103 is set 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 the rear 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 attachment 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.

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

A rear regulating portion 103c is provided behind the spring abutment portion 103a of the right-side slide member 103. When the right-side slide member 103 slides backward to the unlocked position, the rear regulating portion 103c is located behind the second right-side locking member 102, while when the right-side slide member 103 slides forward to 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. This rear regulating portion 103c is configured in the same manner as the front regulating portion 103b, and is a portion that puts the second right-side locking member 102 into a locked state and abuts against the second right-side locking member 102 in the locked state to regulate the retraction of the second right-side locking member 102.

As shown in FIG. 16, the rear end of the right-side sliding member 103, which has slid backward to the unlocked position, protrudes rearward from the rear end face of the right-side seating frame 91. Meanwhile, the front end of the right-side sliding member 103, which is in the unlocked position, is located within the right-side seating frame 91. Then, as shown in FIG. 19, when the right-side sliding member 103 slides forward to the locked position, the front end of the right-side sliding member 103 protrudes forward from the front end face of the right-side seating frame 91.

The front end of the right-side slide member 103 is adapted to be engaged with the right-side side frame 30. As shown in FIG. 10, a right-side insertion hole (insertion portion) 34f is formed as an engagement hole on the front side of the upper frame portion 31 of the right-side side frame 30. This right-side insertion hole 34f is formed in a portion of the upper frame portion 31 that corresponds to the front end of the right-side slide member 103, and opens into the front engagement surface 34a of the front storage recess 34. Therefore, the front end of the right-side slide member 103 in the locked position is inserted into the right-side insertion hole 34f through the opening of the front engagement surface 34a.

The right side slide member 103 in the unlocked position is switched to the locked position in conjunction with the installation 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 installed to the wheelchair body 2. Then, 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. Next, as shown in FIG. 19, when the seat back frame 92 is rotated to the upright state, the right pressing portion 84e abuts against 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 value. 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 setting 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 locked in place, preventing the front end of the right-side seating frame 91 from lifting up when the wheelchair user is seated.

As shown in FIG. 3, the left seating frame 90, like the right seating frame 91, is also 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.

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 with the recessed portion 24e (shown in FIG. 7) formed in the front storage recess 24 of the left side frame 20 in a side view. In a side view, the first left locking member 111 and the front cross beam 97 overlap.

The second left locking member 112 shown in FIG. 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 the recessed portion 25e (shown in FIG. 7) formed in the rear storage recess 25 of the left side frame 20 in a side view. In a side view, the second left locking member 112 and the rear cross beam 98 overlap.

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 locks in place. In addition, the vertical center portion of the second left locking member 112 enters and locks in place in the recessed portion 25e.

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

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

When the left side slide member 113 is in the unlocked position, its rear end protrudes rearward from the rear end face of the left side seating frame 90. Meanwhile, when the left side slide member 113 is in the unlocked position, its front end is located within the left side seating frame 90. Then, when the left side slide member 113 slides forward to the locked position, its front end protrudes forward from the front end face of the left side seating frame 90.

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 storage 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.

The left side slide member 113, which is in the unlocked position, can also be switched to the locked position in conjunction with the attachment 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 abuts against the rear end of the left side slide member 113, pushing 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 a locked state and engage with the recesses 24e and 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, preventing the front end of the left side seating frame 90 from lifting up when the wheelchair user is seated.

(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 that it can be raised and lowered. The sliding surface 103e is inclined so that it is positioned higher toward the rear. In addition, the upper surface of the lifting member 120 is a surface that slides against the sliding surface 103e and is inclined so that it is positioned higher toward the rear. A pin portion 120a that penetrates the right seating frame 91 and protrudes downward is formed on the lower side of the lifting member 120. In addition, a spring 121 that constantly urges the lifting member 120 downward is housed in the right seating frame 91.

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, as shown in Fig. 21, 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. 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 slides against the sliding surface 103e of the right slide member 103, and since the sliding surface 103e is inclined so that it is positioned higher as it moves toward the rear, a force acts forward on the right slide member 103, and the right slide member 103 is switched to the locked position. In other words, 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.

(Variation 2)
23 to 25 show the second modification of the embodiment. The second modification 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.

In this modified example 2, as shown in FIG. 23, when the seat 3 is removed from the wheelchair body 2, the right-side slide member 103 is held in the unlocked position by the biasing force of the right-side coil spring 104, and the front piece 130c of the cam 130 is pushed backward by the rear end of the right-side 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 this cam 130 is transmitted from the front piece 130c to the rear end of the right-side slide member 103, so that the right-side slide member 103 is switched to the locked position as shown in FIG. 24. In other words, the right-side 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. In addition, when the right slide member 103 is switched to the locked 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.

(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.

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 a 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 diagonally backward, the right-side slide member 103 can be removed from the right-side insertion hole 34f, making it possible to remove the seat frame 7.

In addition, in the third modification, the operating lever 150 may not be provided, and the rear end of the right-side slide member 103 may be positioned higher than the upper part in the middle in the fore-and-aft direction. This allows the rear end of the right-side slide member 103 to be manually operated.

(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 part of the wheelchair main body 2 or the drive wheels, etc., thereby improving convenience.

In addition, 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 certain amount of space between them, so that the operating part 74 does not cause discomfort to the seated wheelchair user, improving the riding comfort.

In addition, the operating part 74 of the folding mechanism 70 is disposed between the drive wheels 10, 11 and the casters 12, 13 when viewed from the side of the vehicle body, so that when the wheelchair 1 is lifted by holding the operating part 74, the casters 12, 13 can be prevented from sagging. This allows the wheelchair 1 to be easily moved in a lifted state.

In addition, the wheelchair is equipped with a grip 75 that extends in the direction in which the support arms 51, 61 rotate when switching from the folded state to the unfolded state, so that the wheelchair can be unfolded with one hand by utilizing the weight of the wheelchair body 2.

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

In addition, the locking members 101, 102, 111, and 112 of the seat frame 7 can be engaged with the recesses 24e, 25e, 34e, and 35e of the wheelchair body 2 in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2, so that the seat frame 7 can be firmly attached to the wheelchair body 2 with a simple operation.

In addition, the seat frame 7 can be fixed to the wheelchair body 2 in conjunction with the attachment operation of the seat frame 7 to the wheelchair body 2, making operation simple.

The above-described embodiments are merely illustrative in all respects and should not be interpreted as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention.

As described above, the wheelchair of the present invention can be used, for example, when being carried in a car or the like.

1 Wheelchair 4 Seat cushion portion 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 member 74 Operation portion 74a Support shaft (support member)
75 Grip portion 75a First grip portion 75b Second grip portion 76 Left driven gear portion (first gear portion)
77 Right side driven gear portion (first gear portion)
78 Drive gear section (second gear section)
84d: Locking portion 84e: Pressing portions 90, 91: Left seating frame, right seating frame 93: First left engaging protrusion 94: Second left engaging protrusion 95: First right engaging protrusion 96: Second right engaging protrusion 97, 98: Front cross beam, rear cross beam 101: First right locking member 102: Second right locking member 103: Right slide member 104: Right coil spring (biasing member)
103b Front regulating section 103c Rear regulating section

Claims (4)

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 rotatably connected to the left side frame;
a right support arm rotatably connected to the right side frame;
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,
the folding mechanism includes an operating unit whose operation direction is an up-down direction , and a support member that supports the operating unit switchably between a first operating state in which the operating unit is raised upward and a second operating state in which the operating unit is laid down , and is configured to change the left support arm and the right support arm from an unfolded state to a folded state by a switching operation of the operating unit from the second operating state to the first operating state ,
A wheelchair, characterized in that the operation unit, which is in the first operation state, can be switched to the second operation state by tilting the operation unit toward the rear of the vehicle body . 2. The wheelchair according to claim 1 ,
A wheelchair characterized in that the operation unit, which is in the second operation state, can be switched to the first operation state by lifting the operation unit toward the front of the vehicle body. 3. The wheelchair according to claim 1 or 2 ,
A wheelchair comprising a seat frame that supports a seat cushion portion on which a wheelchair user sits and is configured to be detachable from the left side frame and the right side frame. A wheelchair according to any one of claims 1 to 3 ,
The folding mechanism is provided between the left side frame and the right side frame,
A wheelchair characterized in that the operating unit is formed in a ring shape.

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