EP1002509A1

EP1002509A1 - Traveling vehicle

Info

Publication number: EP1002509A1
Application number: EP99923850A
Authority: EP
Inventors: Hiroko Shikinami; Shigeru Onishi
Original assignee: Nippon Clean Engine Res Inst Co Ltd
Current assignee: Nippon Clean Engine Res Inst Co Ltd
Priority date: 1998-06-15
Filing date: 1999-04-28
Publication date: 2000-05-24
Also published as: WO1999065443A1; CA2300416A1

Abstract

According to the present invention, provision is made of a vehicle for movement which comprises a seating space, front wheels and rear wheels. The front wheels are positioned in front of the seating space. The rear wheels are positioned behind the seating space. A pair of driving wheels is positioned between the front and rear wheels. The driving wheels are placed on and moved off the ground by pivoting rods about predetermined pivot points together with the driving wheels. The rods extend upwardly from the driving wheels. A driving device for driving the driving wheel is mounted on a top end of the rod. The driving device is removed from a side of the seating space by pivoting the rod about the predetermined pivot point together with the driving device.

Description

Technical Field

The invention relates to a vehicle for movement and, in particular, to a manually drivable wheelchair.

Background Art

A wheelchair which comprises a pair of front wheels and a pair of rear wheels, the pair of drive wheels being positioned generally intermediately between the pairs of the front and rear wheels, is known. An occupant of the wheelchair can move it by manually rotating the drive wheels at either side of the wheelchair.
By the way, the space for getting on and off the wheelchair is provided only in the front side of the wheelchair, and thus when the occupant transfers from the wheelchair to, for example, a bed, the occupant must get off the wheelchair through the front side thereof. Therefore, when the wheelchair occupant transfers from the wheelchair to the bed by himself/herself, the occupant must move a front end of the wheelchair close to the bed. However, at the front end of the wheelchair, the wheelchair has portions on which the occupant of the wheelchair rests his/her feet, and thus when the occupant moves the front end of the wheelchair close to the bed, a seat of the wheelchair is still distant from the bed. Further, the occupant of the wheelchair has a handicap regarding his/her feet. Therefore, it is difficult for the occupant to transfer from the wheelchair to the bed by himself/herself, and thus he/she needs help. Of course, if the side of the wheelchair was adjacent to the bed, the seat would be relatively close to the bed. However, the well-known wheelchair is driven by manually rotating the driving wheel, and thus the top end of the driving wheel must be higher than the seat so that the driving wheel becomes an obstacle to transfer from the wheelchair to the bed. Further, in the well-known wheelchair, the driving wheel can be removed, but it is difficult for the occupant of the wheelchair to remove the driving wheel by himself/herself. Therefore, it is still difficult for the occupant of the wheelchair to transfer from the wheelchair to the bed by himself/herself.

Disclosure of Invention

The object of the invention is to provide a vehicle for movement wherein getting on and off through the side of the vehicle can be easily carried out.
According to the first invention, provision is made of a vehicle for movement which comprises: a seating space, front wheels and rear wheels, the front wheels being positioned in front of the seating space, the rear wheels being positioned behind the seating space, a pair of driving wheels being positioned between the front and rear wheels, the driving wheels being placed on and moved from the ground by pivoting rods about predetermined pivot points together with the driving wheels, the rods extending upwardly from the driving wheels wherein a driving device for driving the driving wheel is mounted on a top end of the rod, and the driving device is removed from a side of the seating space by pivoting the rod about the predetermined pivot point together with the driving device.
According to the second invention set forth in the first invention, the driving wheels are positioned generally intermediately between the front and rear wheels.
According to the third invention set forth in the first invention, the driving device is mounted on each driving wheel, and the driving devices are independently drivable.
According to the fourth invention set forth in the first invention, the rod is located in a first predetermined position when the driving wheel is rested on the ground, the driving wheel is moved from the ground when the rod is pivoted about the pivot point from the first predetermined position to a second predetermined position, and a stopper is provided to prevent the movement of the vehicle when the rod is pivoted about the pivot point from the first predetermined position to a third predetermined position beyond the second predetermined position.
According to the fifth invention set forth in the first invention, the driving device comprises a rotatable driving disc and means for transmitting the rotation of the driving disc to the driving wheel.
According to the sixth invention set forth in the fifth invention, the transmission means reduces the rotation speed of the driving disc, and transmits the reduced rotation to the driving wheel.
According to the seventh invention set forth in the first invention, the predetermined pivot point is offset from the rod.
According to the eighth invention set forth in the first invention, the top end of the driving wheel is located lower than the bottom of the seating space.
According to the ninth invention set forth in the first invention, the orientations of the front and rear wheels are changeable to any direction.
According to the tenth invention set forth in the first invention, a plate is provided for defining the seating space between the driving device and the seating space, and the plate is pivotable outwardly from the seating space when the driving device is removed from the side of the seating space.
According to the eleventh invention set forth in the first invention, a backrest for defining the seating space is provided behind the seating space, a protrusion which projects from the backrest is mounted on the backrest, the protrusion is rotatable on a plane generally perpendicular to a plane defined by the backrest, and an extent of the protrusion projecting from the backrest is varied depending on the rotation of the protrusion.
According to the twelfth invention set forth in the first invention, a seat plate for defining the seating space is provided in the bottom of the seating space, the seat plate is laterally separable at the generally intermediately portion of the seat plate in the lateral direction of the seating space.
According to the thirteenth invention set forth in the first invention, at least a part of the vehicle is made of wood.

Brief Description of Drawings

Figure 1 is a side view of the wheelchair of the invention;
Figure 2 is a plan view of the wheelchair of the invention;
Figure 3 is a front view of the wheelchair of the invention;
Figure 4 is a view showing a part of the driving device of the invention;
Figure 5 is a side view of the wheelchair of the invention in which the driving wheel is off the ground;
Figure 6 is a side view of the wheelchair of the invention in which the driving wheel is off the ground and the side plate is pivoted outwardly;
Figure 7 is a plan view of the wheelchair of the invention in which the driving wheel is off the ground and the side plate is pivoted outwardly;
Figure 8 is a front view of the wheelchair of the invention in which the driving wheel is off the ground and the side plate is pivoted outwardly;
Figure 9 is a plan view of the wheelchair of the invention in which the bottom plate is separated;
Figure 10 is a sectional view of the cushion of the invention;
Figure 11 is a view showing an embodiment of the flat type wheelchair which the invention applies; and
Figure 12 is a front view of the wheelchair of the invention made of wood.

Best Mode for Carrying Out the Invention

Figures 1 to 3 are side, plan and front views, respectively, which show an embodiment of a vehicle for movement and, in particular, a wheelchair according to the invention. Referring to figures 1 to 3, the wheelchair 1 of the embodiment has a frame structure 2 for supporting various components of the wheelchair 1. Specially referring to figure 1, the frame structure 2 has a pair of main frames 2a, which generally horizontally extend from a front side of the wheelchair 1 to a back side thereof, then upwardly and generally obliquely vertically extend, and then generally horizontally extend from the back side of the wheelchair 1 to the front side thereof. Referring to figure 3, the main frames 2a are positioned on the right and left sides of the wheelchair 1.
For the convenience of the explanation in this description, relative to the wheelchair considered as a reference in figures 1, 5 and 8 of the drawings, the left side is referred to as "front", the right side is referred to as "back", the upper side is referred to as "upper", the lower side is referred to as "lower", the right to left direction is referred to as "horizontal", and the up and down direction is referred to as "vertical". Further, relative to the wheelchair considered as a reference in figures 3 and 7 of the drawings, the left side is referred to as "right", the right side is referred to as "left", the upper side is referred to as "upper", the lower side is referred to as "lower", the right to left direction is referred to as "horizontal" or "lateral", and the up and down direction is referred to as "vertical". Further, relative to the wheelchair considered as a reference in figures 2, 6 and 9 of the drawings, the left side is referred to as "front", the right side is referred to as "back", the upper side is referred to as "right" and the lower side is referred to as "left".
Specially referring to figure 1, each sub-frame 2b downwardly and generally obliquely vertically extends from a central area of a generally vertically extending portion of each main frame 2a (hereinafter, referred to as vertical frame). Further, specially referring to figure 3, the connections of back ends of generally horizontally extending lower portions of the main frames 2a (hereinafter, referred to as lower horizontal frame) and lower ends of the vertical frames of the main frames 2a are connected by a traverse frame 2c. Further, referring to figure 1, a front end of a generally horizontally extending upper portion of the main frame 2a (hereinafter, referred to as upper horizontal frame) and an intermediate portion of the lower horizontal frame of each main frame 2a are connected by a support frame 2d.
Further, referring to figure 1, a backrest frame 2e is mounted on the rear portion of the main frame 2a, the backrest frame 2e upwardly and generally obliquely vertically extending from one of the back portions of the left upper horizontal frames of the main frames 2a, and referring to figure 3, horizontally extending to the right side of the wheelchair, and then downwardly and generally vertically extending to the other back portion of the right upper horizontal frame of the main frame 2a. The central areas of the generally vertically extending right and left portions of the backrest frame 2e are connected by two generally horizontally extending backrest bars 2f. Two cushions 3 as explained below are mounted on each backrest bar 2f such that the cushions 3 can be pivoted about a central axis of the backrest bar 2f.
As explained above, the frame structure 2 of the invention comprises the pair of the main frames 2a, the pair of the sub-frames 2b, the transverse frame 2c, the pair of the support frames 2d, the backrest frame 2e, and two backrest bars 2f. In the embodiment, a backrest and a backrest face are defined by the backrest frame 2e and two backrest bar 2f, and it is preferable that the backrest frame 2e, two backrest bars 2f and the cushions 3 are covered with a cover not shown. Further, portions of the frame structure may be connected by the mutual insertion for facilitating the assembling of the frame structure.
Referring to figure 1, armrest bars 4 are mounted on the central areas of the generally vertically extending portions of the backrest frame 2e. The armrest bars 4 can be pivoted about an axis X horizontally extending in the right to left direction of the wheelchair 1. The armrest bars 4 shown in figure 1 horizontally extend in the front and back direction of the wheelchair 1. Further, the wheelchair of the embodiment comprises side plates 5 which are pivotable about the support bars 5a which horizontally extend to the front side of the wheelchair 1 from the lower areas of the generally vertically extending portions of the backrest frame 2e. The side plates 5 are generally rectangular thin plate-like members and, as shown in figure 1 are pivotably connected to the support bars 5a at lower edges thereof, and are removably connected to the armrest bars 4 at the upper edges thereof. As shown in figure 7, a groove 4a for housing the upper edge of each side plate 5 is provided on the lower face of each armrest bar 4 so that the side plates 5 are kept under a state shown in figure 1, i.e., a state that the side plates upwardly and generally vertically extend from the support bars 5a by housing the side plates in the grooves 4a of the armrest bars 4.
In the embodiment, side faces of the wheelchair 1 are defined by the side plates 5.
In the wheelchair of the embodiment, referring to figures 1 and 2, a steering link 24 for controlling the movement direction of the front wheels 8b is mounted on the right front wheel 8b. Therefore, the movement direction of the front wheel 8b is controlled to the desired direction by the steering link 24 when the movement direction of the front wheel 8b is not desired.
Referring to figures 2 and 3, a seat support rail 6 extending generally horizontally in the right to left direction in the wheelchair 1 is mounted between the upper horizontal frames of the main frame 2a. A seat plate 7 is mounted on the seat support rails 6. The seat plate 7 comprises right and left seat plate portions 7a and 7b. The seat plate portions 7a, 7b can independently slide in the right to left or lateral direction on the seat support rail 6. In the embodiment, a seat face is defined by the seat plate portions 7a, 7b. Further, in the embodiment, a seating space is defined by the seat face, and the above-mentioned backrest and side faces.
Foot plates 8a, 8b for supporting the sitter's feet when the occupant sits on the seat plate 7 are mounted on the front ends of the lower horizontal frames of the main frames 2a.
In the embodiment, the front wheels 9 are mounted on the front ends of the lower horizontal frames of the main frame 2a. Further, the rear wheels 10 are mounted on the lower ends of the sub-frames 2b. When a force for moving the wheelchair 1 is exerted on the front and rear wheels, the front and rear wheels 9 and 10 change their rolling directions according to the direction of the horizontal component of the force. That is, the rolling directions of the front and rear wheels 9 and 10 are changeable in any direction. Further, the wheelchair 1 of the embodiment comprises driving devices 12 between the front and rear wheels 9 and 10, which devices 12 have driving wheels 11 for driving the wheelchair 1. Therefore, the wheelchair 1 of the embodiment comprises the pair of the front wheels 9, the pair of the rear wheels 10, and the pair of the driving wheels 11 positioned between the front and rear wheels 9 and 10. Next, the driving devices 12 are explained in detail.
Each driving device 12 comprises the driving wheel 11, a circular rotatable driving disc 13 for driving the driving wheel 11, and a driving force transmission mechanism 14 for transmitting the driving force of the driving disc 13 to the driving wheel 11. The driving force transmission mechanism 14 is rod-like member which extends upwardly from the driving wheel 11. Referring to figure 4, pulleys 11a and 13a are mounted on the driving wheel 11 and the driving disc 13, respectively. Therefore, the driving wheel 11 can be rotated about an axis of a shaft 11b together with the pulley 11a, and the driving disc 13 can be rotated about an axis of a shaft 13b together with the pulley 13b. These pulleys 11a, 13a are linked by a flexible belt 20. Further, the pulley 13a of the driving disc 13 has a diameter smaller than that of the pulley 11a of the driving wheel 11. Therefore, in the embodiment, the force necessary to rotate the driving disc 13 to rotate the driving wheel 11 is smaller than that required to directly rotate the driving wheel 11. That is, the reduced rotation speed of the driving disc 13 is transmitted to the driving wheel.
In the embodiment, it is advantageous to use stainless steel, a ceramic, a hard resin, or a polymeric bearing material such as a plastic to provide the bearings of the driving wheel 11 and the driving disc 13 with a self-lubrication feature and to eliminate the supply of the lubrication oil thereto.
Again referring to figure 1, a handle 15 for rotating the driving disc 13 is mounted on the driving disc 13 at a predetermined distance from the shaft 13b of the driving disc 13. Further, a support member (not shown) for rotatably supporting the driving wheel 11 and its pulley 11a is rotatably mounted on the main frame 2a by a support shaft Y. The driving device 12 is not connected to any portion of the wheelchair 1 except for the connection by the support shaft Y. Therefore, as shown in figure 5, the driving wheel 11 is moved off the ground by pivoting the driving disc 13 about an axis Y' of the support shaft Y from a first predetermined position where the driving wheel 11 is on the ground to a second predetermined position. That is, the driving wheel 11 is moved off the floor. Thereby, an aid providing person can move the wheelchair 1 right to left direction, i.e., laterally. Of course, in the embodiment, though it is not shown, the wheelchair 1 has means for keeping the driving disc 13 at the first and second predetermined positions, respectively.
In the embodiment, when the occupant wishes to manually move the wheelchair 1, the occupant can drive the driving wheels 11 by rotating the driving discs 13 which are close to the occupant and are not in contact with the ground without directly manually rotating the driving wheel 11 to drive the driving wheel 11. Therefore, the occupant will not make his hands dirty, and thus the wheelchair 1 of the embodiment is preferable.
Further, in the embodiment, the right and left driving wheels 11 can be independently driven. Therefore, the occupant can turn himself/herself by rotating the right and left driving wheels 11 in the opposite directions. Further, in the embodiment, the driving wheels 11 are located at a generally intermediate position in the front and back direction of the seat plate 7 of the wheelchair 1. Therefore, the occupant can turn himself/herself in a narrow space to change his/her orientation. Therefore, for example, it is convenient to change the orientation in a narrow space such as in the elevator. In order that the occupant can change the orientation in the narrow space, it is preferable to position the driving wheels 11 generally intermediately between the front and rear wheels 9 and 10.
In the embodiment, the position of the pivot point, i.e., the axis Y' about which the driving device 12 is pivoted, is not on a line extending between the rotation shaft 13a of the driving disc 13 and the rotation shaft 11a of the driving wheel 11, and is offset from the line. If the pivot point is on the line extending between the rotation shaft 13a of the driving disc 13 and the rotation shaft 11a of the driving wheel 11, the raising extent of the driving wheel 11 per unit pivoting degree when the driving disc 13 is pivoted about the pivot point becomes larger as the distance between the pivot point and the rotation shaft 11a of the driving wheel 11 becomes larger. Further, the force necessary to pivot the driving disc 13 per unit pivoting degree when the driving disc 13 is pivoted about the pivot point becomes larger as the distance between the pivot point and the rotation shaft 11a becomes larger. That is, the increasing of the raising extent of the driving wheel 11 when the driving disc 13 is pivoted, and the reduction of the force necessary to raise the driving wheel 11 are contrary to each other. However, according to the embodiment, for example, even when the distance between the rotation shaft 11a of the driving wheel 11 and the pivot point becomes small, the force necessary to raise the driving wheels 11 is not increased. Therefore, in the embodiment, the driving wheels 11 can be easily be moved off the floor by pivoting the driving discs 13 by a small angular degree with a small force.
Further, in order to enhance the flexibility of the utility of the wheelchair 1, it is preferable to position the pivot point at a center of the occupant in the front and back direction of the wheelchair 1. In the case that the driving devices 12 can be easily disassembled at the pivot point, the position of the driving discs 13 relative to the occupant is not changed when the right and left driving devices 12 are switched. Therefore, the driving wheels 11 may be moved off the ground when the driving discs 13 are pivoted from the back side of the wheelchair 1 to the front side thereof although, in the shown embodiment, the driving wheels 11 are moved off the ground when the driving discs 13 are pivoted from the front side of the wheelchair 1 to the back side thereof.
The occupant sometimes has to transfer from the wheelchair 1 to, for example, a bed. Of course, the occupant can transfer with an aid providing person's help, but it is convenient that the occupant can transfer by himself/herself. In the embodiment, as shown in figure 6, the occupant can transfer from the wheelchair 1 to, for example, a bed by himself/herself by pivoting the driving disc 13 beyond the second predetermined position to a third predetermined position, pivoting the armrest bar 4 about the axis X', and pivoting the side plate 5 about the support bar 5a. In this manner, the occupant can relatively easily transfer from the wheelchair 1 to a bed when there is no obstacle at the side of the seating space. In the embodiment, the driving disc 13 is removed from the side of the seating space by pivoting the driving disc 13 to the third predetermined position. Thereafter, as explained above, the armrest bar 4 and the side plate 5 are removed from the side of the seating space by pivoting the armrest bar 4, and then pivoting the side plate 5. Thereby, a space through which the occupant transfers is formed at the side of the seating space, and thus the occupant can easily transfer to the bed through the space. Further, as shown in figure 7, the occupant can easily transfer to a bed via the side plate 5 when the pivoted side plate 5 is placed on the bed.
When the driving disc 13 is pivoted to the third predetermined position in order that the occupant can transfer from the wheelchair 1 to the bed by himself/herself, it is necessary to fix the wheelchair 1 to prevent the movement of the same. As shown in figure 6, when the driving disc 13 is pivoted to the third predetermined position, a stopper mounted on a support member (not shown) for supporting the driving wheel 11 rests on the floor. Thereby, the movement of the wheelchair 1 is prevented.
Further, in the embodiment, protrusion bars 17 are slidably housed in the upper horizontal frames of the main frame 2a. As shown in figures 6 and 7, the protrusion bars 17 are projected from the upper horizontal frames of the main frame 2a when the occupant has to get on and off through the front area of the wheelchair 1. The occupant can get on and off by himself/herself through the front area of the wheelchair 1 by using the projected protrusion bars 17.
Further, in the embodiment, when the driving disc 13 should be removed from the side of the seating space, the entire driving device 12 is pivoted about the pivot point. That is, the relationship between the positions of the driving disc 13 and the driving wheel 11 before the driving disc 13 is pivoted to pivot the driving device 12 is not changed from that after the driving disc 13 is pivoted to pivot the driving device 12. When only the driving disc 13 should be removed from the side of the seating space, it may be sufficient to pivot only the driving disc 13, not the entire driving device 12. However, in this case, the relationship between the positions of the driving disc 13 and the driving wheel 11 is changed, and thus the belt 20 positioned between the pulley 13a of the driving disc 13 and the pulley 11a of the driving wheel 11 is loosened when the driving disc 13 is pivoted. Therefore, according to the embodiment, in order to prevent the belt 20 from being loosened, it is preferable to pivot the entire driving device 12.
As explained above, the seat plate 7 of the embodiment comprises the right and left seat plate portions 7a and 7b and, as shown in figure 9, these seat plate portions 7a, 7b can be separated by the sliding on the seat plate support rail 6. As shown in figure 2, in the embodiment, a pair of container support rails 21 forwardly and generally horizontally extends from the seat plate support rail 6. These container support rails 21 support, for example, an evacuation container 22. Therefore, in the embodiment, the occupant can evacuate by laterally separating the seat plate portions 7a, 7b while the occupant remains sitting on the wheelchair.
Front and rear corners 7c, 7d of the seat plate portions 7a, 7b which face each other are rounded. Therefore, the supporter can easily help the after-evacuation treatment of the occupant after the occupant evacuates while the occupant remains sitting on the wheelchair.
Further, a ridge not shown may be provided on a bottom inner wall face of the container 22, which ridge extends upwardly from the inner wall face and front and back along the intermediate line in the right to left direction of the wheelchair 1. Thereby, during the evacuation, splashing of the water in the container is prevented since excreta falls into the water after the excreta bumps into the ridge.
In the embodiment, there is a relatively wide space below the seat plate 7, and there is no obstacle to prevent access to the space. Therefore, since a chamber pot can be housed in the space from the front side of the wheelchair 1 when the container 22 is removed from the container support rails 21, the occupant can evacuate into the chamber pot by himself/herself. Of course, the position of the traverse frame 2c may be suitably changed so as to house the chamber pot in the space from the back side of the wheelchair 1.
Further, as shown in figure 10, a hole 23 in each of the cushions 3 for housing one of the backrest bars 2f of the embodiment is offset from the center of the figure of the section of the cushion 3. The hole 23 is located at distance L1, L2, L3, L4 from the side faces of the cushion 3, respectively, and the distances are in the relationship of L1:L2:L3:L4 = 1:2:3:4. Therefore, the projecting extent of the cushion from the backrest bar 2f can be changed by rotating the cushion 3 on the backrest bar 2f. Therefore, the cushion 3 is a protrusion which is variable in the extent projecting from the backrest face of the cushion 3.
The cross sections of the hole 23 and the backrest bar 2f shown in the drawings are circular, but the cross section of the hole 23 may be circular while the cross section of the backrest bar 2f may be rectangular or, in particular, square to be housed in or pressed into the hole 23, or the cross section of the hole 23 may be rectangular or, in particular, square while the cross section of the backrest bar 2f may be circular to be housed in or pressed into the hole 23, or the cross sections of the hole 23 and the backrest bar 2f may be rectangular or, in particular, square to be fit into the hole 23.
As explained above, the wheelchair of the embodiment has multiple functions. Since the user of the wheelchair often lives using the wheelchair, it is very useful that the wheelchair has multiple functions as in the wheelchair of the embodiment. For example, in addition to the above, to provide a device for raising the seat plate 7 up allows the occupant to reach high objects.
To move the driving wheels 11 off the ground, the driving wheels 11 may be raised up from the floor by lowering the front and rear wheels 9 and 10 below the driving wheels 11 although, in the embodiment, the driving wheels 11 are raised up.
The wheelchair of the embodiment comprises a pair of the front wheels 9, a pair of the rear wheels 10, and a pair of the driving wheels 11 and, however, may comprise only one front wheel instead of a pair of the front wheels or only one rear wheel instead of a pair of the rear wheels.
In the embodiment, the upper structure of the wheelchair, including the backrest frame 2e, the armrest bars 4, the side plates 5, the seat support rail 6, and the seat plate 7 may be disassembled from the main frame 2a, and thereafter, be assembled to the main frame 2a so as to switch the front and back sides thereof.
Figure 11 shows an embodiment of the flat type wheelchair which the invention applies. In this embodiment, the same mechanisms as the above explained embodiment are employed, and the same components are referred to the same reference symbols.
The main frame 2a of the wheelchair shown in figure 11 has a main frame portion 2a'. The main frame portion 2a' is generally U-shaped, and a cushion plate 30 on which the occupant rests his/her feet is mounted on the main frame portion 2a'. A container 32 is provided on the generally central portion of the cushion plate 30, and an opening of the container 32 is closed by a closure 31. The occupant can open the closure 31 by a handle 33 mounted on the closure 31 if necessary. An upper face of the closure 31 is flush with the upper face of the cushion plate 30.
Although the substantial portion, including the frame structure, of the above explained wheelchair and flat type wheelchair is made of the metal, the portion may be made of wood and/or a plastic material. Figure 12 shows a wheelchair made of, for example, wood. In the case that the wheelchair and flat type wheelchair are made of wood or a plastic material, it is preferable that the support shaft Y mounted on the driving wheels 11 is common to the right and left driving wheels as shown in figure 12. Generally, since the strength of wood or a plastic material is lower than that of metal, there may be a possibility that the support shaft may be broken when the support shaft Y is made of the wood or plastic material in the same fashion as the above explained embodiments. However, when the support shaft Y mounted on the frame structure is common to the right and left driving wheels, as in the embodiment shown in figure 12, the support shaft Y is not broken.
In the embodiment shown in figure 12, the backrest frame 2e has a horizontally extending backrest frame portion 2e', and a generally vertically extending backrest frame portions 2e'' at the right and left sides of the backrest frame portion 2e'. The backrest frame 2e is assembled by inserting a projection (not shown) provided on an end face of one of the backrest frame portions into a hole (not shown) provided on an end face of the other of the backrest frame portions. Thereby, since no nails or screws are used to connect the backrest frame portions, the weight of the entire wheelchair is further reduced by making the substantial portion of the wheelchair or the flat type wheelchair of wood.

Explanation of reference symbols

1: Wheelchair
2: Frame structure
2a: Main frame
2b: Sub-frame
2c: Traverse frame
2d: Support frame
2e: Backrest frame
2f: Backrest bar
3: Cushion
4: Armrest bar
4a: Groove of armrest bar
5: Side plate
5a: Support bar
6: Seat plate support rail
7: Seat plate
7a: Seat plate portion
7b: Seat plate portion
8a: Foot plate
8b: Foot plate
9: Front wheel
10: Rear wheel
11: Drive wheel
11a: Pulley
11b: Shaft
12: Driving device
13: Driving disc
13a: Pulley
13b: Shaft
14: Driving force transmission mechanism
15: Handle
16: Stopper
17: Protrusion bar
20: Belt
21: Container support rail
22: Evacuation container
23: Hole
24: Steering link
X': Axis
Y: Support shaft
Y': Axis

Claims

A vehicle for movement comprising: a seating space, front wheels and rear wheels, the front wheels being positioned in front of the seating space, the rear wheels being positioned behind the seating space, a pair of driving wheels being positioned between the front and rear wheels, the driving wheels being placed on and moved off the ground by pivoting rods about predetermined pivot points together with the driving wheels, the rods extending upwardly from the driving wheels wherein a driving device for driving the driving wheel is mounted on a top end of the rod, and the driving device is removed from a side of the seating space by pivoting the rod about the predetermined pivot point together with the driving device.
A vehicle for movement set forth in claim 1
wherein the driving wheels are positioned generally intermediately between the front and rear wheels.
A vehicle for movement set forth in claim 1
wherein the driving device is mounted on each driving wheel, and the driving devices are independently drivable.
A vehicle for movement set forth in claim 1
wherein the rod is located in a first predetermined position when the driving wheel is placed on the ground, the driving wheel is moved off the ground when the rod is pivoted about the pivot point from the first predetermined position to a second predetermined position, and a stopper is provided to prevent the movement of the vehicle when the rod is pivoted about the pivot point from the first predetermined position to a third predetermined position beyond the second predetermined position.
A vehicle for movement set forth in claim 1
wherein the driving device comprises a rotatable driving disc and means for transmitting the rotation of the driving disc to the driving wheel.
A vehicle for movement set forth in claim 5
wherein the transmission means reduces the rotation speed of the driving disc, and transmits the reduced rotation to the driving wheel.
A vehicle for movement set forth in claim 1
wherein the predetermined pivot point is offset from the rod.
A vehicle for movement set forth in claim 1
wherein the top end of the driving wheel is located lower than the bottom of the seating space.
A vehicle for movement set forth in claim 1
wherein the orientations of the front and rear wheels are changeable to any direction.
A vehicle for movement set forth in claim 1
wherein a plate is provided for defining the seating space between the driving device and the seating space, and the plate is pivotable outwardly from the seating space when the driving device is removed from the side of the seating space.
A vehicle for movement set forth in claim 1
wherein a backrest for defining the seating space is provided behind the seating space, a protrusion which projects from the backrest is mounted on the backrest, the protrusion is rotatable on a plane generally perpendicular to a plane defined by the backrest, and an extent of the protrusion projecting from the backrest is varied depending on the rotation of the protrusion.
A vehicle for movement set forth in claim 1
wherein a seat plate for defining the seating space is provided in the bottom of the seating space, the seat plate is laterally separatable at the generally intermediately portion of the seat plate in the lateral direction of the seating space.
A vehicle for movement set forth in claim 1
wherein at least a part of the vehicle is made of wood.