JP2007082865A - Wheelchair with back inclination angle adjusting mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheelchair 2 reducing rubbing of the body of a user with a back seat when reclining back frames 8 and easily raising the back frames 8. <P>SOLUTION: This wheelchair 2 is provided with a pair of main frames 4, a pair of seat face bars 6, the pair of back frames 8, a pair of arm frames 10, two pairs of cross members 12 and a pair of connecting devices 14. The main frame 4 has a base bar 30, a support bar 32, a front bar 34, a back bar 36 and a reinforcing bar 38. The front end of the back bar 36 is journaled to the rear end of the front bar 34 by a pin 42. The lower end of the back frame 8 is joined with the rear end of the back bar 36 by welding. The back frame 8 and the back bar 36 integrally rotationally turn around the pin 42 relative to the front bar 34. The rotational turning can adjust the inclination angle of the back frame 8. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wheelchair used for a physically handicapped person, an elderly person, an injured person and the like.

  Wheelchairs are used by people who have difficulty walking on their own, such as people with physical disabilities. A user uses a wheelchair for the purpose of sitting or moving. The user may continue to use the wheelchair for a long time. It is painful for the user to maintain a constant posture for a long time. Japanese Patent Laid-Open No. 2003-190222 discloses a wheelchair provided with a reclining mechanism and excellent in comfort. In a reclining type wheelchair, the back frame rotates around a joint point between the seat bar and the back frame. By this rotation, the posture of the user changes.

  The user uses a wheelchair with his / her weight on the back seat. The user's body is in contact with a part of the back sheet through clothes. When the back frame is tilted in this state, the portion of the back seat that contacts the user's body moves. While the back frame is rotating, the body and the back seat rub against each other. This rubbing is uncomfortable for the user.

Japanese Patent Application Laid-Open No. 2005-103248 discloses a wheelchair having a hinge in the middle of a seating surface. In this wheelchair, the user's buttocks drop downward when the back frame is tilted down. In this wheelchair, there is little friction between the user's body and the back seat.
JP 2003-190222 A JP-A-2005-103248

  In the wheelchair disclosed in Japanese Patent Application Laid-Open No. 2005-103248, the user has to raise the buttocks in order to raise the fallen back frame. This action requires force. Many users are inferior in muscle strength. A user with poor muscular strength cannot raise the back frame without the assistance of another person.

  An object of the present invention is to provide a wheelchair in which the user's body and the back seat are less rubbed when the back frame is tilted and the back frame can be easily raised.

  The wheelchair according to the present invention includes a pair of main frames, a pair of seating surface bars that are placed on the main frame and form a seating surface, and a pair of back frames that form a back surface. The main frame includes a base bar extending in the front-rear direction, a front bar positioned above the base bar and extending in the front-rear direction, and is pivotally supported by the front bar near the rear end of the front bar. And a back bar that can be rotated. The back frame is attached to the back bar behind the center of rotation of the back bar relative to the front bar. The back frame and the back bar are integrally rotated with respect to the front bar, whereby the inclination angle of the back surface can be adjusted.

  Preferably, the wheelchair further includes a pair of arm frames. The arm frame includes a front standing part and a rear standing part. The lower end of the front erection part is attached to the front bar, and the lower end of the rear erection part is attached to the base bar.

  Preferably, the arm frame includes an intermediate portion that is located between the front erection portion and the rear erection portion and extends in the front-rear direction. The back frame is located between one intermediate portion and the other intermediate portion. The rear standing part is inclined inward in the width direction toward the lower side.

  Preferably, the wheelchair further includes a pair of cross members pivotally supported on each other and a pair of connecting tools. In this cross member, the lower end is pivotally supported by the base bar, and the upper end is joined to the seating surface bar. In this connecting tool, one end is pivotally supported by the cross member, and the other end is pivotally supported by the rear standing part.

  In this wheelchair, the center of rotation when the back frame is tilted is located in front of the back frame. The center of rotation of the human body when the back frame is tilted is also forward of the back frame. In this wheelchair, the center of rotation of the back frame is close to the center of rotation of the human body. In this wheelchair, there is little friction between the human body and the back seat when the back frame is tilted down. In this wheelchair, the position of the seat surface formed by the seat surface bar does not depend on the rotation of the back frame. In this wheelchair, the user's buttocks are not depressed even when the back frame is collapsed. The user can easily raise the back frame.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a front view showing a wheelchair 2 according to an embodiment of the present invention, FIG. 2 is an enlarged front view showing a part thereof, and FIG. 3 is an enlarged right side showing a part thereof. FIG. The left-right direction in FIGS. 1 and 2 is the front-rear direction of the wheelchair 2. The horizontal direction in FIG. 3 is the width direction of the wheelchair 2.

  The wheelchair 2 includes a pair of main frames 4, a pair of seating surface bars 6, a pair of back frames 8, a pair of arm frames 10, two pairs of cross members 12, and a pair of connecting tools 14. The wheelchair 2 further includes a telescopic member 16, an operation lever 18, a pair of front wheels 20, a pair of rear wheels 22, a leg support 24, a pusher 26, and an armrest 28. Accessories such as a tag brake may be attached to the wheelchair 2.

  As shown in FIG. 2, the main frame 4 includes a base bar 30, a support bar 32, a front bar 34, a back bar 36, and a reinforcing bar 38. The base bar 30 is located at the lowest position in the main frame 4 and extends substantially in the front-rear direction. The support bar 32 extends substantially in the vertical direction. The lower end of the support bar 32 is joined to the front end of the base bar 30 by welding. A front wheel 20 (a caster in this example) is attached to the support bar 32. A leg support 24 is also attached to the support bar 32. The front bar 34 is located above the base bar 30 and extends substantially in the front-rear direction. The front end of the front bar 34 is joined to the upper end of the support bar 32 by welding. Two receivers 40 are attached to the front bar 34 at a predetermined interval. The back bar 36 is located behind the front bar 34. The front end of the back bar 36 is pivotally supported by the pin 42 on the rear end of the front bar 34. The reinforcing bar 38 is curved. One end of the reinforcing bar 38 is joined to the front bar 34 by welding. The other end of the reinforcing bar 38 is joined to the arm frame 10 by welding.

  The seat bar 6 extends substantially in the front-rear direction. The seat bar 6 is placed on the receiving tool 40. Although not shown, a seat is stretched between one seat bar 6 and the other seat bar 6. The user places the buttocks on the seat. In other words, the seat surface bar 6 forms a seat surface.

  The back frame 8 extends substantially in the vertical direction. The lower end of the back frame 8 is joined to the rear end of the back bar 36 by welding. Although not shown, a back seat is stretched between one back frame 8 and the other back frame 8. The user leans his back against the back sheet. In other words, the back frame 8 forms the back surface. The pusher 26 is located at the upper end of the back frame 8. When the assistant pushes the wheelchair 2, the assistant holds the pusher 26.

  The arm frame 10 includes a front standing part 44, an intermediate part 46, and a rear standing part 48. The front erection part 44 and the rear erection part 48 extend substantially in the vertical direction. The intermediate part 46 extends substantially in the front-rear direction. The lower end of the front standing part 44 is joined to the front bar 34 by welding. The operation lever 18 is attached to the front upright portion 44. An armrest 28 is attached to the upper surface of the intermediate portion 46. The lower end of the rear standing part 48 is joined to the base bar 30 by welding. The axle of the rear wheel 22 is attached to the rear standing part 48.

  As is clear from FIG. 1, the rear standing part 48 is located rearward of the back frame 8. As is apparent from FIG. 3, the rear upright 48 is curved. A part of the rear standing part 48 (specifically, the upper half) is inclined downward inward in the width direction. The intermediate portion 46 is located on the outer side in the width direction than the back frame 8. In other words, the two back frames 8 are located between one intermediate portion 46 and the other intermediate portion 46.

  As shown in FIG. 3, the pair of cross members 12 are pivotally supported by pins 44. One cross member 12 can rotate with respect to the other cross member 12 around the pin 44. The upper end of the cross member 12 is joined to the seating surface bar 6 by welding. The lower end of the cross member 12 is pivotally supported by a pin receiver 48 by a pin 46. The pin receiver 48 is joined to the base bar 30. In other words, the lower end of the cross member 12 is pivotally supported on the base bar 30 via the pin receiver 48. The cross member 12 can rotate with respect to the base bar 30 around the pin 46. As described above, the wheelchair 2 includes two pairs of cross members 12. As apparent from FIG. 1, one pair of one cross member 12 and the other pair are arranged at a predetermined interval in the front-rear direction.

  The elastic member 16 extends substantially in the front-rear direction, and is slightly inclined downward. The front end of the elastic member 16 is pivotally supported by a pin receiver 52 by a pin 50. The pin receiver 52 is attached near the front end of the base bar 30. The elastic member 16 can rotate with respect to the base bar 30 around the pin 50. The rear end of the elastic member 16 is pivotally supported by a pin receiver 56 by a pin 54. The pin receiver 56 is attached near the rear end of the back bar 36. The elastic member 16 can rotate with respect to the back bar 36 around the pin 54. In FIG. 1, the elastic member 16 is in a compressed state. Although not shown, one end of a wire is connected to the elastic member 16. The other end of the wire is connected to the operation lever 18. Usually, the elastic member 16 is locked. When the operation lever 18 is operated and the wire is pulled, the lock is released. By releasing the lock, the elastic member 16 develops an urging force in the extending direction. A typical elastic member 16 is an air spring. As the elastic member 16, a coil spring, an oil cylinder, or the like may be used.

  FIG. 4 shows the connecting tool 14. In FIG. 4, the cross member 12 and the rear standing part 48 are also shown. In FIG. 4, the left-right direction is the front-rear direction of the wheelchair 2. The planar shape of the connecting tool 14 is a crank shape. The connecting tool 14 connects the cross member 12 and the rear standing part 48. Although the cross member 12 is located in front of the rear standing part 48 at a predetermined distance, the cross member 12 and the rear standing part 48 can be connected by using the crank-shaped connecting tool 14. One end of the connecting tool 14 is pivotally supported on the cross member 12 by a pin 58. The connecting tool 14 can rotate with respect to the cross member 12 around the pin 58. The other end of the connecting tool 14 is pivotally supported on the rear standing part 48 by a pin 60. The connecting tool 14 can rotate with respect to the rear standing part 48 around the pin 60. The connecting tool 14 maintains the positional relationship between one main frame 4 and the other main frame 4.

  FIG. 5 is an enlarged right side view showing a part of the wheelchair 2 of FIG. FIG. 5 shows the wheelchair 2 in a folded state. In the transition from the state shown in FIG. 3 to the state shown in FIG. 5, one cross member 12 is moved with respect to the other cross member 12 around the pin 44 as shown by an arrow A in FIG. 3. Rotate. At this time, the lower end of the cross member 12 rotates with respect to the base bar 30 around the pin 46. Further, in the connecting tool 14, one end rotates with respect to the cross member 12 around the pin 58, and the other end rotates with respect to the rear standing part 48 around the pin 60. By these operations, the cross member 12 stands. Since the seat bar 6 is joined to the upper end of the cross member 12 as described above, the seat bar 6 rises away from the main frame 4 by the standing of the cross member 12. The width W2 shown in FIG. 5 is smaller than the width W1 shown in FIG. The folded wheelchair 2 is compact.

  FIG. 6 is an enlarged front view showing a part of the wheelchair 2 of FIG. In FIG. 6, the state where the back frame 8 is tilted is indicated by a two-dot chain line. To tilt the back frame 8, the user M pulls the operation lever 18 (see FIG. 1) while putting his / her weight on the back seat. When the operation lever 18 is pulled, the telescopic member 16 is unlocked. Although the expansion / contraction member 16 is in a compressed state, the expansion / contraction member 16 further contracts because it receives weight through the back frame 8 and the pin receiver 56. At this time, the back frame 8 and the back bar 36 are integrally rotated in the direction indicated by the arrow B around the pin 42. Thus, the angle formed by the back frame 8 and the front bar 34 is increased. The change in angle is indicated by a double arrow α in FIG. The pin 42 that is the center of rotation is located in front of the lower end of the back frame 8. Since the pin 42 is close to the rotation center P of the human body of the user M, there is little friction between the human body and the back seat caused by the rotation of the back frame 8. User M can comfortably adjust the inclination angle of the back surface.

  A double arrow L in FIG. 6 indicates the distance between the lower end of the back frame 8 and the pin 42. The distance L is measured in a state where the angle formed by the back frame 8 and the front bar 34 is the smallest. From the viewpoint of user comfort, the distance L is preferably 100 mm or more, and more preferably 140 mm or more. The distance L is preferably 250 mm or less.

  Since the seat bar 6 is placed on the front bar 34 via the support 40, the position of the seat bar 6 does not change even if the back bar 36 rotates. In other words, the position of the seating surface is constant without depending on the angle α. In the wheelchair 2, the buttock H does not drop even when the back frame 8 is tilted down. When the back frame 8 is raised, the user pulls the operation lever 18 while moving the center of gravity forward. When the operation lever 18 is pulled, the elastic member 16 is unlocked and the elastic member 16 extends. The back frame 8 is urged by the elastic member 16, and the angle α is reduced. Since the buttocks H are not depressed, the user is not required to have great muscular strength even when the back frame 8 is raised. The user can raise the back frame 8 without a helper.

  In the wheelchair 2, the back bar 36 rotates, so the arm frame 10 cannot be joined to the back bar 36. In the wheelchair 2, the rear standing part 48 of the arm frame 10 is joined to the base bar 30. Thereby, the rotation of the back bar 36 is allowed. The joining of the rear standing part 48 and the base bar 30 also contributes to the rigidity of the wheelchair 2.

  In the wheelchair 2, as described above, the rear standing part 48 is located behind the back frame 8, and a part of the rear standing part 48 is inclined downward inward in the width direction. Therefore, a sufficient space is secured between the back frame 8 and the rear upright portion 48. Further, the intermediate portion 46 is located on the outer side in the width direction than the back frame 8. Even when the back frame 8 is tilted, the back frame 8 does not interfere with the arm frame 10. The arm frame 10 allows the back bar 36 to rotate.

  In a normal wheelchair, the connecting tool connects the cross member and the main frame. In the wheelchair 2 according to the present invention, since the back bar 36 that is a part of the main frame 4 rotates, the connecting tool 14 (see FIG. 4) cannot be pivotally supported by the main frame 4. In the wheelchair 2, the connecting tool 14 is pivotally supported by the rear standing part 48 as described above. The pivoting of the back bar 36 is allowed by this shaft support. In the wheelchair 2, the reclining function and the folding function are both achieved by the connecting tool 14 pivotally supported by the rear standing part 48.

  The present invention can be applied to both self-propelled wheelchairs and assistive wheelchairs.

FIG. 1 is a front view showing a wheelchair according to an embodiment of the present invention. FIG. 2 is an enlarged front view showing a part of the wheelchair of FIG. FIG. 3 is an enlarged right side view showing a part of the wheelchair of FIG. FIG. 4 is an enlarged plan view showing the connecting tool of the wheelchair of FIG. FIG. 5 is an enlarged right side view showing a part of the wheelchair of FIG. FIG. 6 is an enlarged front view showing a part of the wheelchair of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Wheelchair 4 ... Main frame 6 ... Seating surface bar 8 ... Back frame 10 ... Arm frame 12 ... Cross member 14 ... Connecting tool 16 ... Telescopic member 18. ..Control lever 20 ... Front wheel 22 ... Rear wheel 30 ... Base bar 32 ... Support bar 34 ... Front bar 36 ... Back bar 38 ... Reinforcement bar 40 ... Receiver Ingredients

Claims (4)

A pair of main frames, a pair of seating bars that are placed on the main frame and form a seating surface, and a pair of back frames that form the back surface,
The main frame includes a base bar extending in the front-rear direction, a front bar positioned above the base bar and extending in the front-rear direction, and is pivotally supported by the front bar near the rear end of the front bar. And a back bar that can rotate
A back frame is attached to the back bar behind the center of rotation of the back bar with respect to the front bar. A wheelchair configured to be adjustable in angle. It further includes a pair of arm frames,
This arm frame has a front standing part and a rear standing part,
The wheelchair according to claim 1, wherein a lower end of the front upright portion is attached to the front bar, and a lower end of the rear upright portion is attached to the base bar. The arm frame includes an intermediate portion that is positioned between the front standing portion and the rear standing portion and extends in the front-rear direction.
The back frame is located between one intermediate part and the other intermediate part;
The wheelchair according to claim 1 or 2, wherein the rear standing part is inclined inward in the width direction toward the lower side. A pair of cross members that are pivotally supported with each other, and a pair of connecting members;
In this cross member, its lower end is pivotally supported by the base bar, and its upper end is joined to the seating surface bar,
The wheelchair according to any one of claims 1 to 3, wherein one end of the connecting tool is pivotally supported by the cross member, and the other end is pivotally supported by the rear upright portion.

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