JP2006288841A - Wheelchair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheelchair capable of enlarging the elevating/lowering stroke of a seat, facilitating height adjustment on this occasion, and dispensing with a horizontal rod for connecting right and left side frames in order to arrange the seat height adjusting means. <P>SOLUTION: A seat elevator 30 including a hydraulic jack is attached to the middle part of the right and left side frames 11 constituting the wheel base 10 of the wheelchair, so as to allow the distal end of the piston rod of the hydraulic jack to be directed upward. A horizontal shaft 43 is freely rotatably supported to the distal end of the piston rod via an upward extending bracket. While fixing a sprocket 44 to the horizontal shaft, a cylindrical upper post 33 enclosing the piston rod and bracket is arranged so as to be freely elevating/lowering possible. A chain drive 46 is wound around the sprocket 44 from an upper part, whose one end 46a is fixed to the lower end side of the hydraulic jack and whose other end is fixed to the lower end side of the upper post 33. The seat 50 with a backrest 60 is fixed to the upper end of the upper post 33. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a wheelchair, and the seat thereof is formed so as to be movable up and down to facilitate getting on and off the automobile and moving between the beds, thereby reducing the burden on the caregiver.

Wheelchairs that are moved by the caregiver's hand are generally equipped with small-diameter free wheels on the front left and right of the chassis as front wheels, rear wheels with large-diameter wheels on the left and right, and seats with a backrest at the top of the chassis. It is constructed by attaching a handle for a caregiver to the rear of the chassis. The left and right side frames constituting the chassis are connected so as to be extendable in the width direction, fixed to the maximum width when used, and reduced in width when stored. In addition, the above-mentioned seat with a backrest is made detachable.

In such a wheelchair, in order to easily get on and off an automobile or the like, it is known that the seat is formed to be movable up and down. For example, in Patent Document 1 below, a rectangular link mechanism comprising four equal-length links under a seat is set such that one pair of opposing two axes faces up and down, and the other two opposing axes face front and rear. The distance between two opposed axes in the front-rear direction is adjusted with a feed screw, thereby changing the distance between the two opposed axes in the vertical direction to adjust the seat height. Further, in Patent Document 2 below, a seat is connected to a vehicle body via a link mechanism so as to be movable up and down, and an inclination angle of a lower link in the link mechanism is adjusted by an electric cylinder in the front-rear direction, thereby raising and lowering the seat. What has been made is disclosed.
Japanese Utility Model Publication No. 04-131226 JP 2000-254179 A

All of the above wheelchairs can adjust the seat height, but in all cases, feed screws or electric cylinders are installed in the front-rear direction in the center of the width direction of the chassis, and these ends are used for connecting the left and right side frames. Since it is connected to the horizontal bar, it was difficult to fold the wheelchair. In addition, since the front-rear direction feed screw or electric cylinder is used and the front-rear direction contraction of the link mechanism is changed to the vertical direction extension, the up-down stroke is less than half of the total length of the chassis, so the up-down stroke is small and the seat height when traveling is 45 cm The height at the time of ascent is only about 60cm, and the burden on the caregiver increases when the car gets in and out of the car or moves between the beds. In particular, in the invention of Patent Document 1, since the feed screw is rotated by hand, the burden on the caregiver increases, and since the invention described in Patent Document 2 uses an electric cylinder, a heavy battery needs to be loaded. there were.

In the present invention, the lift stroke of the seat is set to be as large as about 50 cm, the seat height can be increased from about 45 cm during traveling to about 1 m, the height adjustment at that time is easy, and the seat height It is an object of the present invention to provide a wheelchair that does not require connecting horizontal bars for the left and right side frames in order to install the height adjusting means, and thus can easily install a link mechanism that enables folding of the chassis.

In this invention, a hydraulic jack is attached between the left and right side frames constituting the chassis of the wheelchair so that the tip of the piston rod faces upward, and the horizontal shaft is rotated via a bracket extending upward to the tip of the piston rod. The sprocket is fixed to the horizontal shaft, and a cylindrical upper post surrounding the piston rod and bracket is provided so as to be movable up and down, and a transmission chain is wound around the sprocket from above, and one end thereof is The hydraulic jack is fixed to the lower end side, the other end is fixed to the lower end side of the upper post, and the seat with the backrest is fixed to the upper end of the upper post.

In the above invention, when the hydraulic jack is operated and the piston rod is raised, the horizontal shaft and the sprocket supported at the tip via the bracket are raised at the same speed as the piston rod. At this time, a transmission chain is wound around the sprocket from above, one end of which is fixed to the lower end side of the hydraulic jack, and the other end is fixed to the lower end side of the upper post which can be raised and lowered. As the sprocket rises, the sprocket moves upward while being pulled by one end side of the transmission chain, that is, the hydraulic cylinder side portion, and pulls up the upper post at the other end side of the transmission chain, that is, the upper post side portion.

Therefore, the seat fixed to the upper end of the upper post rises by a distance equal to the raising stroke of the horizontal axis relative to the hydraulic jack with respect to the horizontal axis. That is, the lift stroke of the seat is twice the lift stroke of the piston rod. For example, the lifting stroke of the seat can be doubled to 50 cm with a hydraulic jack with a lifting stroke of 25 cm. By using a telescope type hydraulic jack, the stroke is further increased, so that the cylinder portion of the hydraulic jack can be reduced in size and weight.

Further, according to the present invention, the hydraulic jack is used upright, and the hydraulic jack forms a jacket around the cylinder to form an oil reservoir, and a manual pump for sending the oil in the oil reservoir to the cylinder is provided at the lower end of the outer surface of the oil reservoir. Since it is provided in contact with the portion, it is sufficient to provide only the hydraulic cylinder and the manual pump between the left and right side frames constituting the chassis. Therefore, it is possible to provide a link mechanism for connecting the space between the left and right side frames so that the space can be expanded and contracted. For example, the left and right side frames constituting the chassis are connected to each other by two sets of front and rear link mechanisms crossing in an X shape so as to expand and contract in the width direction, and the intersections of the front link mechanism and the rear link mechanism are connected to the front of the hydraulic jack and It is connected with a support shaft protruding from the rear surface, and can be fixed to the maximum width when the wheelchair is used, and can be reduced when accommodated. In addition, the seat can be detachably fixed to the upper end of the upper post above the hydraulic jack. In this case, the seat can be removed when the wheelchair is stored, and the storage is further facilitated. Further, when the manual lever of the manual pump is replaced with a foot pedal, the caregiver does not need to release his hand from the handwheel, and the safety is improved accordingly.

A first sprocket is fixed to both ends of the horizontal shaft, and a second sprocket having a diameter different from that of the first sprocket is fixed to the center, and transmission chains are respectively attached to the first sprocket and the second sprocket from above. One end of the transmission chain wound around the first sprocket is fixed to the lower end side of the hydraulic jack, and the other end is suspended downward, preferably urged downward to be always tensioned, and wound around the second sprocket. One end of the hung transmission chain hangs downward, preferably urges downward and is always tensioned, and the other end can be fixed to the lower end side of the upper post. In this case, the first sprocket and the second sprocket The up / down stroke of the upper post, that is, the seat increases or decreases according to the diameter ratio of the upper post. For example, if the diameter of the second sprocket is set to 1.2 times that of the first sprocket, the lift stroke of the seat increases to 2.2 times the lift stroke of the hydraulic jack itself. Therefore, the cylinder portion can be further reduced in size as compared with the case where only one sprocket is used or when the diameters of the first and second sprockets are made equal.

According to the first aspect of the present invention, since the hydraulic jack is used to raise and lower the seat, and the stroke is given to the seat twice as much as the hydraulic jack using the sprocket, the lifting stroke of the seat is compared with the conventional one. As will be described later, the seat can be easily raised to a height that is at least twice as high as when traveling, and it is easy to get on and off the car, etc. It is reduced. Since a wide space is formed between the left and right side frames, various improvements such as forming the chassis to be foldable are facilitated. In addition, the wheelchair according to claim 2 can adjust the lift stroke of the seat in various ways by setting the diameter ratio of the first sprocket and the second sprocket, and the lift stroke of the seat can be adjusted to 2 of the stroke of the hydraulic jack as necessary. The space between the left and right side frames can be maintained at the same level as in the first aspect of the invention. Moreover, since the space | interval of the right-and-left side frame which comprises a chassis can be narrowed in the invention which concerns on Claim 3, accommodation becomes easy. The invention according to claim 4 can further increase the lifting stroke.

The wheelchair shown in FIG. 1 includes a chassis 10, a seat elevator 30, and a seat 50 above the chassis 10. A small-diameter front wheel 12 is provided at the front lower end of the chassis 10, and a large-diameter rear wheel 13 is provided at the rear lower end. A push handle 14 is provided above the rear part. The seat elevator 30 has a rectangular post-shaped lower post 31, a middle post 32, and an upper post 33 connected in a nested or telescope form, and a telescope type hydraulic cylinder described later is built inside. The seat base 34 is fixed to the upper end of the upper post 33, and the seat 50 is detachably attached to the upper surface of the seat base 34. Note that a backrest 60 is foldably connected to the seat 50.

The side frame 11 of the chassis 10 is formed into a long rectangular shape in the longitudinal direction by a longitudinal front stay 11a, a rear stay 11b, a longitudinal stay 11c and a lower stay 11d made of an aluminum tube. 11a
A front wheel 12 of a free wheel is attached to the lower end of the rear wheel, and a large-diameter rear wheel 13 is attached near the lower end of the rear stay 11b. The rear stay 11b extends upward and has a connection fitting 11e at its upper end.
A hand handle 14 is connected to the hand handle 14 so that it can be bent downward, and a brake lever 14 a for operating a brake (not shown) of the rear wheel 13 is provided on the hand handle 14.

The side frames 11 are provided on the paper back side and the front side in FIG. 1, and as shown in FIG. 3, the left and right side frames 11 are two sets of X-shaped link mechanisms including two links 15 and 16. Connected by Here, the intersections of the two links 15 and 16 are connected by support shafts 31a (see FIG. 1) that project from the front and rear surfaces of the lower post 31 of the seat elevator 30, respectively. Further, as shown in FIG. 3, the two links 15 and 16 are formed slightly longer in the lower half of the lower part than the upper part of the upper part of the crossing part. The lower end of the lower stay 11d of the side frame 11 is
On the other hand, when the left and right side frames 11 are widened to the maximum distance, the left and right front and rear two and the right front and rear two are respectively connected by round bars 17 in the front and rear direction. Two round bars 17 are the upper stays 11c of the side frames 11.
The left and right side frames 11 are firmly connected to each other by fitting into a receiving metal 17a projecting from the inside. Of the two sets of front and rear links described above, the rear links 15 and 16 each have an intermediate portion in the upper half thereof, and an auxiliary link 18 and a rear stay 11b of the side frame 11.
When the left and right side frames 11 are widened to the maximum distance, the auxiliary link 18 is extended horizontally.

As described above, the seat elevator 30 is installed in a suspended manner between the intersections of the two sets of front and rear links 15 and 16 via the support shafts 31a provided on the front and rear surfaces of the lower post 31. As shown in FIGS. 1 and 2, on the left and right sides of the lower post 31, a base plate 31b is provided.
The support bar 31c in the front-rear direction is fixed via the base, and this support bar 31c contacts the upper surface of the lower half of the front and rear links 15 and 16 when the left and right side frames 11 are expanded to the maximum width as described above. It is like that. That is, the seat elevator 30 includes a support shaft 31a located in the upper center of the lower post 31 and support rods 31c on the lower left and right sides thereof.
Is supported at the three points of the intersection and lower half of the links 15, 16. When the wheelchair is stored, the width is reduced by removing the upper ends of the links 15 and 16 from the bracket 17a and standing at the chain line position.

As shown in FIG. 2, the seat elevator 30 includes a hydraulic jack 35 inside a lower post 31, and the lower post 31 is erected on a base 36. 32 and the upper post 33 are sequentially inserted. The hydraulic jack 35 is provided with a base 36 at the lower end, an oil reservoir jacket (not shown) is formed on the inner side, and a first-stage rod 37 and a second-stage rod 38 on the inner cylinder portion. . Further, a manual pump 39 (see FIG. 3) is provided on the base 36 so as to contact the back of the lower post 31 and send the oil in the oil reservoir to the cylinder. A drive lever for the piston rod 39a is provided. The foot pedal 41 is fixed to 40. Further, an oil drain cock knob (not shown) is provided on the side surface of the hydraulic jack 35.

In FIG. 2, the lower end of the U-shaped bracket 42 is connected to the upper end of the two-stage rod 38 of the hydraulic jack 35, and straddles the upper ends of a pair of left and right columnar portions extending upward and the upper end of the middle post 32. The horizontal shaft 43 in the width direction is rotatably attached, and the first sprocket 44 is fixed to both ends of the horizontal shaft 43, that is, the left and right protruding ends of the middle post 32, and the center of the horizontal shaft 43, that is, the U-shaped bracket 42. The second sprocket 45 is fixed between the upper ends of the two. The upper post 33 is provided with a guide hole 33a which is long in the vertical direction on the left and right side plates, and the horizontal shaft 43 is passed through the guide hole 33a.

Here, the second sprocket 45 at the center is omitted, the first sprockets 44 on the left and right sides are used, and a transmission chain 46 is wound around the first sprocket 44 from above as shown in FIG. The hanging lower end 46a at the rear of the chassis 10 is fixed to the bottom of the lower post 31, and the front hanging lower end 46b is fixed to the lower end of the upper post 33. In this state, the hydraulic jack 35 is driven by stepping on the pedal 41. When the horizontal shaft 43 is lifted through the first-stage rod 37 and the second-stage rod 38, the first sprocket 44 rotates in the counterclockwise direction while being lifted. To rise. Accordingly, the seat base 34 rises at a speed twice that of the first sprocket 44 from the solid line position to the chain line position. The same applies when the second sprocket 45 is used instead of the first sprocket 44.

On the other hand, using both the first sprocket 44 and the second sprocket 45 having a diameter larger than that of the first sprocket 44, as shown in FIG. 2, the rear of the transmission chain 46 wound around the first sprocket 44 (paper surface). Front side) The lower end 46a is fixed to the bottom of the lower post 31 and the other end (back side end) is urged downward by a spring or the like to be tensioned, and the transmission chain 47 wound around the second sprocket 45 is Back (front side of paper) hanging end 47a
Is biased downward and tensioned, and the opposite front (paperback side) hanging lower end portion is fixed to the lower end of the upper post 33. In this state, the hydraulic jack 35 is driven, and the first-stage rod 37 and the second-stage rod 38 described above are driven. When the horizontal shaft 43 is raised through the first post, the first sprocket 44 and the first sprocket 45 rotate in the same direction while being raised, so that the upper post 33 rises with respect to the middle post 32 as described above.

In this case, the lift stroke ratio and the lift speed ratio of the horizontal shaft 43 and the seat base 34 are determined by the diameter ratio of the first sprocket 44 and the second sprocket 45. For example, when the number of teeth of the first sprocket 44 and the second sprocket 45 is 19 and 24, respectively, the lifting stroke of the seat base 34 with respect to the horizontal shaft 43 is 1.26 times the lifting stroke of the horizontal shaft 43. Become. Therefore, when a hydraulic jack having a stroke of 22 cm is used, the lift stroke of the seat base 34 with respect to the horizontal shaft 43 is 27.7 cm, and the total stroke, which is the total, is about 50 cm. And when using a telescope type hydraulic jack with a total height of 185 mm, the height of the lower post 31 is about 40 cm, so it can be attached to a wheelchair with a seat height of about 45 cm and a lifting stroke of about 50 cm exceeding the seat height is obtained. It is done. The lowering of the seat is performed by operating the oil drain cock.

As shown in FIGS. 1 and 4, the seat base 34 fixed to the upper end of the upper post 33 has a rectangular base plate shape that is long in the front-rear direction, and two rear hooks 34a on the left and right sides face upward. The left and right latches 34b are fixed to the lower surface on the opposite front edge side. On the other hand, the seat 50 mounted on the seat base 34 connects the rear part and the middle part of a pair of left and right vertical frames 51 made of an aluminum pipe, which are long in the front-rear direction, with a pair of front and rear horizontal frames 52 made of an aluminum pipe, In addition, the vertical frame 51 is bent downward in front of the front horizontal frame 52, the footrest 53 is fixed to the lower end, and a rectangular portion formed by the horizontal portion of the vertical frame 51 and the front and rear horizontal frames 52 is formed. It is formed by stretching a seat 54 (see FIG. 1). The latch 34b of the seat base 34 is placed on the front of the front horizontal frame 52.
Corresponding to the left and right front hooks 55 are fixed. When the seat 50 is placed on the seat base 34, the rear lateral frame 52 is fitted into the rear hook 34a of the seat base 34, and then the front hook of the seat 50 is placed. 55 and the latch 34b of the seat base 34
And the seat 50 is fixed.

The backrest 60 attached to the seat 50 is formed by bending a similar aluminum tube into a U shape and stretching a seat for backrest (not shown), which is formed in an inverted U shape, and both ends thereof are The seat 50 is foldably connected to the rear part. In other words, the rear end of the armrest 61 is pin-connected to the middle part of the backrest 60, the upper end of the front link 62 is pin-connected to the front end of the armrest 61, and the lower end is rearward of the front lateral frame 52 of the seat 50. Pin-connected to the vertical frame 51. On the other hand, the lower end of the backrest 60 is pin-connected to the vertical frame 51 in front of the rear horizontal frame 52 of the seat 50 via the short link 63, and further near the lower end of the backrest 60, that is, above the connecting portion of the short link 63. This portion is pin-connected to the vertical frame 51 via the lower link 64 at the same position as the front link 62. Then, the backrest 60 is folded by being tilted in the direction of arrow A in FIG.

It is a longitudinal cross-sectional view of embodiment. It is a longitudinal cross-sectional view of a seat elevator including a hydraulic jack. It is a rear view of FIG. It is a top view of a seat.

Explanation of symbols

10: chassis 11: side frame 14: hand handle 15, 16: link 31a: support shaft, 31c
: Support bar 17: Round bar 17a: Receptacle 30: Seat elevator 31: Lower post 32: Middle post 33: Upper post 34: Seat base 35: Hydraulic jack 36: Base 37: 1 step rod 38: 2 step rod 39: Manual pump 40: Driving lever 41: Foot pedal 42: U-bracket 43: Horizontal shaft 44, 45: Sprocket 46, 47: Transmission chain 50: Seat 51: Vertical frame 52: Horizontal frame 53: Footrest 54: For seat Seat 60: Back 61: Armrest

Claims (4)

A hydraulic jack is attached to the middle of the left and right side frames that make up the wheelchair chassis so that the piston rod tip faces upward, and the horizontal axis is rotatably supported via the bracket extending upward to the piston rod tip. A sprocket is fixed to the horizontal shaft, and a cylindrical upper post surrounding the piston rod and bracket is provided so as to be movable up and down. A transmission chain is wound around the sprocket from above, and one end thereof is a lower end of the hydraulic jack. The wheelchair is fixed to the side, the other end is fixed to the lower end side of the upper post, and a seat with a backrest is fixed to the upper end of the upper post. A hydraulic jack is attached to the middle of the left and right side frames that make up the wheelchair chassis so that the piston rod tip faces upward, and the horizontal axis is rotatably supported via the bracket extending upward to the piston rod tip. The first sprocket is fixed to both ends of the horizontal shaft, and the second sprocket having a diameter different from that of the first sprocket is fixed to the center, and the cylindrical upper post surrounding the piston rod and the bracket is movable up and down. The transmission chain is wound around the first sprocket and the second sprocket from above, one end of the transmission chain wound around the first sprocket is fixed to the lower end side of the hydraulic jack, and the other end is suspended downward. , One end of the transmission chain wound around the second sprocket is suspended downward, and the other end is Wheelchair, characterized in that fixed to the lower end of the. The left and right side frames constituting the chassis are connected to each other by two sets of front and rear link mechanisms intersecting in an X shape so that the front link mechanism and the rear link mechanism intersect with each other at the front of the hydraulic jack. The wheelchair according to claim 1, wherein the wheelchair is connected by a shaft projecting from a rear surface. The wheelchair according to any one of claims 1 to 3, wherein the hydraulic jack is of a telescope type.

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