JP7762049B2 - Wheelchair training wheels and wheelchairs with training wheels - Google Patents

Description

The present invention relates to wheelchair training wheels that can be detachably attached to a wheelchair, and to a wheelchair equipped with such wheelchair training wheels.

Self-propelled wheelchairs typically have a pair of rear wheels (main wheels), each consisting of a large diameter, and a pair of front wheels, each consisting of a small diameter swivel wheel. A self-propelled wheelchair is moved by the occupant operating the hand rims attached to the pair of rear wheels, or by an assistant operating a pair of hand grips from behind. Therefore, a self-propelled wheelchair can be turned by adjusting the magnitude and direction of the force with which the occupant operates the pair of hand rims, or the force with which an assistant operates the pair of hand grips.

When moving such a wheelchair closer to a bedside, for example, it is necessary to move the wheelchair diagonally forward and backward repeatedly to gradually move the wheelchair widthwise. Therefore, if there is not enough space to move forward and backward, moving the wheelchair closer to the bedside becomes difficult.

JP 2003-284744 A (Patent Document 1) describes a wheelchair equipped with an assistive device that allows movement in any direction, including sideways (widthwise), by operating the pedals to lower the second auxiliary wheel and place it in contact with the ground, while keeping the large wheel (rear wheel) off the ground.

Japanese Patent Application Laid-Open No. 2003-284744

The wheelchair described in JP 2003-284744 A has the following problems:

In other words, self-propelled wheelchairs are typically designed to be foldable in the width direction so that the left and right rear wheels are closer together for storage and transportation. However, in the structure described in JP 2003-284744 A, the assist device is fixed to the frame between the left and right rear wheels, making it impossible to fold in the width direction.

In consideration of the above-mentioned circumstances, the present invention aims to provide a wheelchair training wheel structure that allows the wheelchair to move in any direction and also allows the wheelchair to be folded for storage or transportation.

The wheelchair training wheels of the present invention are:
a first frame portion having an attachment portion that is detachably attached to a frame of a wheelchair;
a second frame portion supported so as to be movable up and down relative to the first frame portion;
an elevator device that raises and lowers the second frame relative to the first frame portion;
a swivel supported by the second frame portion so as to be rotatable about a vertically disposed pivot axis;
Equipped with.

In other words, the lifting device displaces the first frame portion and the second frame portion relative to each other in the vertical direction.

One aspect of the wheelchair training wheels of the present invention can include a linear guide that supports the second frame portion so that it can be raised and lowered relative to the first frame portion. In this case, one of the guide rail and slider that make up the linear guide is supported and fixed to the first frame portion, and the other of the guide rail and slider is supported and fixed to the second frame portion.

In one aspect of the wheelchair training wheels of the present invention, the lifting device can include a locking mechanism that prevents the second frame portion from rising relative to the first frame portion when the second frame portion is lowered relative to the first frame portion, i.e., when the swivel wheel is in contact with the ground.

A wheelchair training wheel according to one aspect of the present invention may include multiple, for example, two (a pair) of the swivel wheels.

In one aspect of the wheelchair training wheels of the present invention, the lifting device can be equipped with a link mechanism having a first link member whose one longitudinal end is supported relative to the first frame portion or a member supported and fixed to the first frame portion so as to be swingable about a first pivot axis disposed in the width direction, and a second link member whose one longitudinal end is supported relative to the other longitudinal end of the first link member so as to be swingable about a second pivot axis disposed in the width direction, and whose intermediate longitudinal portion is supported relative to the second frame portion or the second frame portion so as to be swingable about a third pivot axis disposed in the width direction.

In other words, the lifting device comprises a link mechanism having a first link member and a second link member whose proximal ends are supported so as to be able to swing about a second pivot axis arranged in the width direction, and the first link member supports its distal end relative to the second link member against the first frame portion or a member supported and fixed to the first frame portion so as to be able to swing about the first pivot axis arranged in the width direction, and the second link member can support its longitudinal intermediate portion against the second frame portion or a member supported and fixed to the second frame portion so as to be able to swing about a third pivot axis arranged in the width direction.

In this case, the second link member may have a pedal portion at the other longitudinal end, i.e., the distal end relative to the first link member, that is operated by the caregiver's foot.

Alternatively, in the wheelchair training wheel according to one aspect of the present invention, the lifting device can include a feed screw mechanism and an electric motor.
In this case, the feed screw mechanism comprises a screw shaft having a male thread groove on its outer peripheral surface and connected to one of the first frame portion and the second frame portion, and a nut having a female thread groove on its inner peripheral surface and connected to the other of the first frame portion and the second frame portion, and is configured so that the screw shaft and the nut can be displaced relative to each other in the axial direction by rotating the screw shaft and the nut relative to each other.
The electric motor is configured to be able to rotate the screw shaft or the nut.

In this case, the feed screw mechanism may include a plurality of rolling elements disposed between the male thread groove and the female thread groove so as to be able to roll freely. That is, the feed screw mechanism may be configured as a ball-type feed screw mechanism.
Alternatively, the feed screw mechanism may be configured as a sliding type feed screw mechanism in which the male screw groove and the female screw groove are in direct sliding contact with each other.

In one aspect of the wheelchair training wheel of the present invention, the mounting portion can be detachably attached to a portion of the frame that coincides with the rotation axis of the rear wheel that constitutes the wheelchair in the front-to-rear direction.

A wheelchair with training wheels according to one aspect of the present invention comprises:
The frame and
a pair of rear wheels supported on the frame so as to be rotatable only about rear wheel axes disposed horizontally;
a front wheel supported on the frame so as to be able to rotate about a front wheel side pivot shaft disposed in a vertical direction and a front wheel shaft disposed in a horizontal direction;
a wheelchair training wheel detachably attached to the frame;
Equipped with.

In particular, in a wheelchair with training wheels according to one aspect of the present invention, the wheelchair training wheels are the wheelchair training wheels according to one aspect of the present invention.

The wheelchair training wheels of the present invention allow the wheelchair to move in any direction and also allow the wheelchair to be folded for storage or transport.

FIG. 1 is a side view showing a wheelchair equipped with wheelchair training wheels according to a first embodiment, with the swivel wheels raised. FIG. 2 is a side view showing a wheelchair equipped with wheelchair training wheels according to the first embodiment, with the swivel wheels lowered. FIG. 3 is a rear view of a wheelchair fitted with wheelchair training wheels according to a first embodiment, viewed from the rear side, with the swivel wheels raised. FIG. 4 is a rear view of a wheelchair fitted with wheelchair training wheels according to the first embodiment, seen from the rear side with the swivel wheels lowered. FIG. 5 is a rear view of the wheelchair training wheels according to the first embodiment, seen from the rear side with the swivel wheels raised. FIG. 6 is a rear view of the wheelchair training wheels according to the first embodiment, seen from the rear side with the swivel wheels lowered. FIG. 7 is a plan view of FIG. 5 as seen from above. 8A is a cross-sectional view taken along line AA in FIG. 5, and FIG. 8B is a cross-sectional view taken along line BB in FIG. 9A is a cross-sectional view taken along the line CC in FIG. 5, and FIG. 9B is a cross-sectional view taken along the line DD in FIG. FIG. 10 is a partially enlarged view showing an example of a wheelchair to which the wheelchair training wheels according to the first embodiment can be attached. 11A to 11C are diagrams for explaining the operation of the lifting device in the first example of the embodiment. FIG. 12 is a rear view of the wheelchair in a folded state, as seen from the rear. FIG. 13 is a side view showing a wheelchair equipped with wheelchair training wheels according to a second embodiment, with the swivel wheels raised. FIG. 14 is a side view showing a wheelchair equipped with wheelchair training wheels according to a second embodiment, with the swivel wheels lowered. FIG. 15 is a rear view of a wheelchair fitted with wheelchair training wheels according to a second embodiment, viewed from the rear side with the swivel wheels raised. FIG. 16 is a rear view of a wheelchair fitted with wheelchair training wheels according to a second embodiment, as viewed from the rear side with the swivel wheels lowered. FIG. 17 is a rear view of the wheelchair training wheels according to the second embodiment, seen from the rear side with the swivel wheels raised. FIG. 18 is a rear view of the wheelchair training wheels according to the second embodiment, seen from the rear side with the swivel wheels lowered. FIG. 19 is a plan view seen from above in FIG. 20A is a cross-sectional view taken along line EE in FIG. 17, and FIG. 20B is a cross-sectional view taken along line FF in FIG. 21A is a cross-sectional view taken along line GG in FIG. 17, and FIG. 21B is a cross-sectional view taken along line HH in FIG. 22A and 22B are diagrams for explaining the operation of the lifting device in the second example of the embodiment.

[First Example of Embodiment]
A first embodiment of the present invention will be described with reference to Figures 1 to 12. Wheelchair training wheels 1 of this embodiment are detachably attached to a frame 3 of a folding wheelchair 2. First, an example of the structure of a folding wheelchair 2 will be briefly described below, followed by an explanation of the structure of wheelchair training wheels 1 of this embodiment, their attachment structure to the frame 3, and their operation.

<Structure of wheelchair 2>
The wheelchair 2 comprises a frame 3, a pair of rear wheels 4, and a pair of front wheels 5.

In this example, the frame 3 comprises a pair of side parts 6 and a cross pipe 7.

The side part 6 has a rear vertical member 8, a front vertical member 9, an upper horizontal member 10, and a lower horizontal member 11.

The rear vertical member 8 has a column 12 that extends vertically and a bent portion 13 that bends at a substantially right angle from the top end of the column 12 toward the rear. A handgrip 14 is attached to the tip (rear end) of the bent portion 13, which the caregiver can grasp when operating the wheelchair 2.

The front vertical member 9 is positioned in front of the rear vertical member 8 so as to extend vertically.

The upper horizontal member 10 is stretched in the front-to-rear direction, spanning the middle (vertical middle) of the rear vertical member 8 and the upper end of the front vertical member 9. In this example, the rear end of the upper horizontal member 10 is connected and fixed to the middle part of the rear vertical member 8, and the upper end of the front vertical member 9 is connected and fixed to the middle part (front-to-rear middle) of the upper horizontal member 10.

The upper horizontal member 10 also has a bent portion 15 that bends downward, located forward of the portion where the upper end of the front vertical member 9 is connected. A foot support 16 is attached to the tip (lower end) of the bent portion 15 for the passenger to rest their feet on.

The lower horizontal member 11 is connected between the lower end of the rear vertical member 8 and the lower end of the front vertical member 9 so as to extend in the front-to-rear direction. In this example, the lower end of the rear vertical member 8 is connected and fixed to the rear portion of the lower horizontal member 11, and the lower end of the front vertical member 9 is connected and fixed to the front portion of the lower horizontal member 11. Furthermore, in this example, the front end of the lower horizontal member 11 is connected and fixed to the middle portion of the bent portion 15 (the middle portion in the up-down direction).

The lower horizontal member 11 also has a tipping lever 17 on the part of the lower horizontal member 11 that protrudes further rearward than the rear vertical member 8. The tipping lever 17 is a part that the caregiver steps on with their foot to lift the pair of front wheels 5 into the air when climbing over a step, etc.

Although not shown, the frame 3 can be equipped with arm supports for the rider to rest their elbows on, and side guards to prevent the rider's clothing from getting caught in the rear wheel 4.

The arm support has a horizontal member extending in the front-to-rear direction and a vertical member bent downward from the front end of the horizontal member, and is spanned between the rear vertical member 8 and the upper horizontal member 10. That is, the rear end of the horizontal member is connected and fixed to a portion of the rear vertical member 8 above the portion to which the rear end of the upper horizontal member 10 is connected, and the lower end of the vertical member is connected and fixed to the middle portion of the upper horizontal member 10 (the portion to which the upper end of the front vertical member 9 is connected and fixed).

The side guards are attached to the area surrounded by the arm support, rear vertical member 8, and upper horizontal member 10.

The cross pipe 7 rotatably supports the longitudinal middle portions of a pair of link members 18. One of the pair of link members 18 supports its longitudinal end (lower end) on one side relative to the lower horizontal member 11 of one of the pair of side parts 6 so as to be rotatable about a pivot axis disposed in the fore-and-aft direction, while the other link member 18 supports its longitudinal end (lower end) on one side relative to the lower horizontal member 11 of the other side part 6 so as to be rotatable about a pivot axis disposed in the fore-and-aft direction. This allows the frame 3 to be configured so that the pair of side parts 6 can be folded closer together in the width direction. A seat support member 19 disposed in the fore-and-aft direction is supported and fixed to the other longitudinal end (upper end) of each link member 18. The cross pipe 7 is provided at one or more locations in the fore-and-aft direction between the pair of side parts 6.

Each of the pair of rear wheels 4 is supported for free rotation around a rear wheel axle 54 arranged in the width direction (horizontal direction) on the lower portion of the rear vertical member 8 of the side part 6 (between the portion where the rear end of the upper horizontal member 10 is connected and fixed and the portion where the rear end of the lower horizontal member 11 is connected). Each rear wheel 4 is equipped with a hand rim 20 that allows the occupant to operate the wheelchair 2 themselves.

Each of the pair of front wheels 5 is supported to rotate freely about a vertically disposed swivel axis (front wheel side swivel axis) _C5 and a horizontally disposed rotation axis (front wheel axis) _O5 relative to the lower end of the front vertical member 9 of the side part 6. In other words, each of the front wheels 5 is constituted by a swivel wheel (swivel caster).

The wheelchair 2 further includes a seat cushion 78 stretched between the seat support members 19, and a back seat (not shown) stretched between the upper halves of the rear vertical members 8 (portions that protrude above the portions where the rear ends of the upper horizontal members 10 are joined) that make up a pair of side parts 6. The seat cushion 78 and back seat are made of flexible material.

<Structure of wheelchair training wheels 1>
The wheelchair training wheel 1 comprises a first frame portion 21, a second frame portion 22, a pair of linear guides 23, a lifting device 24, and a pair of swivel wheels 25. In the following description, the terms "up-down direction,""front-reardirection," and "width direction (left-right direction)" refer to the up-down direction, front-rear direction, and width direction (left-right direction) of the wheelchair 2 when the wheelchair training wheel 1 is supported on the frame 3 of the wheelchair 2, unless otherwise specified.

The first frame portion 21 has a pair of first beam members 26a, 26b, a pair of first connecting members 27, and a pair of first columnar members 28.

The pair of first beam members 26a, 26b are arranged parallel to each other and spaced apart in the front-to-rear direction so as to extend in the width direction.

The pair of first connecting members 27 connect the longitudinal ends (widthwise ends) of the pair of first beam members 26a, 26b. That is, each first connecting member 27 has its front end connected and fixed to the longitudinal end of the front first beam member 26a of the pair of first beam members 26a, 26b, and its rear end connected and fixed to the longitudinal end of the rear first beam member 26b. Therefore, the first frame portion 21 is configured in a generally rectangular frame shape when viewed from the top and bottom.

Furthermore, each first connecting member 27 has a notch 29 that penetrates vertically and opens to the front end face. Therefore, when viewed from the vertical direction, the first connecting member 27 has a generally U-shaped or J-shaped planar shape (a generally J-shaped shape in the illustrated example). In this example, as will be described later, the shank of a mounting screw 57 supported on the frame 3 of the wheelchair 2 is engaged with the notch 29, thereby supporting the wheelchair training wheel 1 relative to the frame 3. In other words, in this example, the mounting portion is formed by the first connecting member 27.

The pair of first pillars 28 are arranged to extend vertically, and their upper ends are fixedly connected to the longitudinal end (widthwise end) of the front first beam member 26a. In other words, each first pillar 28 is configured to hang down (extend) downward from the longitudinal end of the front first beam member 26a.

The second frame section 22 has a pair of second columnar members 30, a second beam member 31, a pair of hanging members 32, and a second connecting member 33.

The pair of second columnar members 30 are arranged parallel to each other and spaced apart in the width direction so as to extend in the vertical direction.

The second beam member 31 is disposed behind the pair of second columnar members 30 and connects the longitudinal middle portions (vertical middle portions) of the pair of second columnar members 30 together (spanning between the longitudinal middle portions of the pair of second columnar members 30). That is, the second beam member 31 has one longitudinal end (one widthwise end) connected and fixed to the longitudinal middle portion of the second columnar member 30 on one widthwise side of the pair of second columnar members 30, and has the other longitudinal end (other widthwise end) connected and fixed to the longitudinal middle portion of the second columnar member 30 on the other widthwise side.

The pair of hanging members 32 are arranged to extend vertically, and their upper ends are fixedly connected to two positions in the middle of the length (middle of the width) of the second beam member 31. In other words, each hanging member 32 is configured to hang (extend) downward from two positions in the middle of the length of the second beam member 31.

The second connecting member 33 connects the lower ends of the pair of hanging members 32 (is stretched between the lower ends of the pair of hanging members 32). In other words, the end on one lengthwise side (the end on one widthwise side) of the second connecting member 33 is joined and fixed to the lower end of the hanging member 32 on one widthwise side of the pair of hanging members 32, and the end on the other lengthwise side (the end on the other widthwise side) is joined and fixed to the lower end of the hanging member 32 on the other widthwise side.

In this example, the second frame portion 22 is supported by a pair of linear guides 23 so that it can move up and down relative to the first frame portion 21. In other words, the first frame portion 21 and the second frame portion 22 are combined by the pair of linear guides 23 to allow relative vertical displacement. Each linear guide 23 has a rectangular plate-shaped guide rail 34 that extends vertically, and a slider 35 that has a generally U-shaped end face when viewed vertically and is combined with the guide rail 34 so that it can only move vertically along the guide rail 34. In this example, the guide rail 34 is fixedly coupled to the front side of the second pillar member 30 of the second frame portion 22, and the slider 35 is fixedly coupled to the rear side of the first pillar member 28 of the first frame portion 21. However, the guide rail may be fixedly coupled to the first frame portion, and the slider may be fixedly coupled to the second frame portion.

The linear guide 23 may be any of a sliding linear guide, a ball circulating linear guide, or a non-circulating roller linear guide. A sliding linear guide is constructed by engaging an engaging protrusion formed on a slider with a rail groove formed in the guide rail. A ball circulating linear guide has multiple balls rollably arranged in a load path provided between the guide rail and the slider, and a circulation path is provided inside the slider that returns balls that move to the end of the load path due to relative displacement between the guide rail and the slider to the start of the load path. A non-circulating roller linear guide is constructed by having multiple rollers rotatably supported on the slider roll in contact with the rolling surface formed on the guide rail.

The wheelchair training wheel 1 of this example includes a torsion coil spring (tension spring) 36 stretched between the first frame portion 21 and the second frame portion 22. Specifically, in this example, the upper end of the torsion coil spring 36 is supported and fixed to the first beam member 26b on the rear side of the first frame portion 21, and the lower end is supported and fixed to the upper end of the hanging member 32 of the second frame portion 22. As will be described later, the torsion coil spring 36 is provided to prevent the second frame portion 22 from descending (falling) relative to the first frame portion 21 due to its own weight when the locking mechanism of the lifting device 24 is released.

The lifting device 24 raises and lowers the second frame portion 22 relative to the first frame portion 21. In other words, the lifting device 24 displaces the first frame portion 21 and the second frame portion 22 relative to each other in the vertical direction. In this example, the lifting device 24 has a non-electric structure, more specifically, a foot-operated structure in which the pair of swivel wheels 25 are lowered when the caregiver presses on the pedal portion 51 described below. In this example, the lifting device 24 includes an expandable member 37 and a link mechanism 38.

The telescopic member 37 is made up of an upper first member 39 and a lower second member 40 combined in a manner that allows the entire length to be extended or contracted (telescopically).

The first member 39 has a first support plate portion 41 having a substantially rectangular plate shape and a first cylindrical portion 42 extending downward from the underside of the first support plate portion 41. The first member 39 is supported and fixed to the first frame portion 21. Specifically, the first member 39 supports and fixes the first support plate portion 41 to the undersides of the pair of first beam members 26a, 26b of the first frame portion 21 by screwing.

The second member 40 has a second support plate portion 43 having a generally rectangular plate shape, and a second cylindrical portion 44 that extends upward from the upper surface of the second support plate portion 43 and is fitted within the first cylindrical portion 42 so as to allow relative vertical displacement relative to the first cylindrical portion 42. The second member 40 is supported and fixed to the second frame portion 22. Specifically, the second member 40 supports and fixes the second support plate portion 43 to the second connecting member 33 of the second frame portion 22 by screwing.

The expandable member 37 has a tension spring (not shown) stretched between the first member 39 and the second member 40. The tension spring applies elastic force to the first member 39 and the second member 40 in a direction that brings them closer to each other, i.e., in a direction that contracts the entire length of the expandable member 37. As will be described later, the tension spring is provided to prevent the second frame portion 22 from descending (falling) relative to the first frame portion 21 due to its own weight when the locking mechanism of the lifting device 24 is released.

The link mechanism 38 has a first link member 45, a second link member 46, and a locking link member 47.

The first link member 45 extends in a generally linear manner when viewed in the width direction, and its end on one side in the longitudinal direction (the distal end relative to the second link member 46, the upper end) is supported so as to be able to swing about a first pivot 48 arranged in the width direction relative to the first member 39, which is supported and fixed to the first frame portion 21.

The second link member 46 has a generally V-shaped (approximately L-shaped) side view when viewed from the width direction. One longitudinal end of the second link member 46 (the proximal end relative to the first link member 45, the front end) is supported so as to be able to swing about a second pivot 49 arranged in the width direction relative to the other longitudinal end of the first link member 45 (the proximal end relative to the second link member 46, the lower end). The second link member 46 also has a longitudinal intermediate portion (bent portion) supported so as to be able to swing about a third pivot 50 arranged in the width direction relative to the second member 40, which is supported and fixed to the second frame portion 22. Furthermore, the second link member 46 has a pedal portion 51 at its other longitudinal end (the distal end relative to the first link member 45, the rear end) that is stepped on by the caregiver.

The locking link member 47 has a generally V-shaped (approximately L-shaped) side profile when viewed from the width direction. The locking link member 47 is supported at its longitudinal middle portion so that it can swing about a third pivot 50. The locking link member 47 also has an engagement notch 52 at one longitudinal end (front end) and an unlocking pedal 53 at the other longitudinal end (rear end).

The pair of swivel wheels 25 are supported by the lower surfaces of the pair of second pillar-shaped members 30 constituting the second frame portion 22 so as to be able to rotate freely about a vertically disposed pivot axis _C25 . Each swivel wheel 25 has a substantially flat mounting plate 79, a wheel support portion 80, and a wheel 81.

The wheel support portion 80 is formed by bending a metal plate into a substantially U-shape, and has a pair of parallel support plate portions 82 and a connecting portion 83 that connects the upper ends of the pair of support plate portions 82. The connecting portion 83 is supported by the mounting plate 79 so as to be able to rotate freely about a pivot axis _C25 disposed in the vertical direction.

The wheel 81 is supported by a pair of support plate portions 82 so as to be freely rotatable about a rotation axis O ₂₅ disposed in the horizontal direction.

Each swivel wheel 25 is supported so as to be freely rotatable about a pivot axis C ₂₅ arranged in the vertical direction relative to the second frame portion 22 by supporting and fixing the mounting plate 79 to the underside of the second columnar member 30.

<Attachment structure of wheelchair training wheels 1 to frame 3>
The wheelchair training wheels 1 of this example are detachably attached to the frame 3 of the wheelchair 2. Specifically, a pair of first connecting members 27 that constitute the mounting portion are detachably attached to a portion of the frame 3 that coincides in the front-to-rear position with the rear wheel axle 54 of the rear wheel 4. For this purpose, mounting brackets 55 are supported and fixed to the rear vertical members 8 of the pair of side parts 6 that constitute the frame 3.

Each mounting bracket 55 comprises a bracket body 56 and a mounting screw 57.

The metal fitting body 56 comprises a side plate portion 58 having a through hole penetrating in the width direction, and a bent plate portion 59 that bends inward in the width direction from the lower end of the side plate portion 58 and has a screw hole penetrating in the thickness direction (vertical direction). The metal fitting body 56 is supported and fixed to the rear vertical member 8 with the rear wheel axle 54 of the rear wheels 4 of the wheelchair 2 inserted through the through hole provided in the side plate portion 58.

The tip of the shaft of the mounting screw 57 is loosely screwed from above into a threaded hole in the bent plate portion 59 of the metal fitting body 56. In this example, the mounting screw 57 has a clamp handle 60 on its head.

When attaching the wheelchair training wheels 1 to the frame 3, first, move the wheelchair training wheels 1 from the rear to the front of the frame 3 and insert them between the pair of side parts 6. Then, the base end of the shank of each mounting screw 57 that is exposed above the upper surface of the bent plate portion 59 engages with the notches 29 provided on the pair of first connecting members 27. In other words, the base end of the shank of each mounting screw 57 is positioned inside the notches 29 of the respective first connecting members 27.

With the base end of the shaft of each mounting screw 57 engaged with the notch 29 of each first connecting member 27, each mounting screw 57 is further screwed in, increasing the amount of engagement of the mounting screw 57 with the threaded hole provided in the bent plate portion 59. Then, the portions of each first connecting member 27 on both sides of the notch 29 in the width direction are tightly clamped between the head of the mounting screw 57 and the bent plate portion 59 of the metal fitting body 56. In this way, the wheelchair training wheel 1 is supported on the frame 3.

In contrast, when removing the wheelchair training wheels 1 from the frame 3, first, the mounting screws 57 are loosened to reduce the amount by which the mounting screws 57 are threaded into the screw holes provided in the bent plate portions 59. This reduces or eliminates the force that clamps the portions of each first connecting member 27 on both sides of the notch 29 in the width direction between the head of the mounting screws 57 and the bent plate portions 59 of the metal fitting body 56.

Next, move the wheelchair training wheel 1 rearward relative to the frame 3 to disengage the base end of the shaft of each mounting screw 57 from the notch 29 of each first connecting member 27. In other words, move the base end of the shaft of each mounting screw 57 forward out of the notch 29 of each first connecting member 27. This removes the wheelchair training wheel 1 from the frame 3.

<Operation of wheelchair training wheels 1>
In the wheelchair 2 fitted with the wheelchair training wheels 1 of this example, an attendant can step on the pedal portion 51 of the wheelchair training wheels 1 to lower the pair of swivel wheels 25 so that they touch the ground, and also raise the pair of rear wheels 4 of the wheelchair 2 so that they do not touch the ground.

When the caregiver depresses the pedal 51 provided on the other longitudinal end of the second link member 46 (the distal end relative to the first link member 45, the rear end), as shown in Figures 11(A) and 11(B), the second link member 46 swings around the third pivot 50 in a direction such that its other longitudinal end faces forward and downward, and its one longitudinal end (the proximal end relative to the first link member 45, the front end) faces backward and upward, i.e., in the clockwise direction in Figures 11(A) and 11(B).

As the second link member 46 swings, the second pivot 49 supported on one longitudinal end of the second link member 46 moves rearward and upward. This causes the other longitudinal end of the first link member 45 (the proximal end relative to the second link member 46, or rear end) to swing rearward and upward, i.e., counterclockwise in Figures 11(A) and 11(B), around the first pivot 48. This increases the distance between the first pivot 48 and the third pivot 50, and the first member 39 supporting the first pivot 48 and the second member 40 supporting the third pivot 50 move away from each other against the elastic forces of the torsion coil spring 36 and the tension springs provided in the expansion member 37. As a result, the overall length of the expansion member 37 extends.

In this example, when the overall length of the telescopic member 37 reaches its maximum, the engagement notch 52 of the locking link member 47 engages with the second pivot 49, restricting movement of the second pivot 49. This locks the telescopic member 37 from extending or retracting over its entire length.

In a wheelchair 2 equipped with the wheelchair training wheels 1 of this example, when an attendant presses down on the pedal portion 51 of the wheelchair training wheels 1 to extend the entire length of the telescopic member 37, the first frame portion 21 supported by the frame 3 of the wheelchair 2 first remains in place, while the second frame portion 22 descends. Then, the pair of swivel wheels 25 (wheels 81) supported by the second frame portion 22 come into contact with a contact surface 85, such as the ground or floor.

When the pedal 51 is further depressed from the state in which the pair of swivel wheels 25 are in contact with the ground, extending the entire length of the telescopic member 37, the first frame 21 rises relative to the second frame 22 while the second frame 22 remains in its current position, lifting the rear portion of the frame 3 of the wheelchair 2 higher than the front portion. As a result, the pair of front wheels 5 remain in contact with the ground surface 85, while the pair of rear wheels 4 move away from the ground surface 85 (reach a non-grounded state). Then, when the first frame 21 reaches its full elevation relative to the second frame 22, the engagement notch 52 of the locking link member 47 engages with the second pivot 49, locking the extension and contraction of the entire length of the telescopic member 37. This maintains the state in which the pair of swivel wheels 25 are in contact with the ground and the pair of rear wheels 4 are not in contact with the ground.

When the pair of rear wheels 4 are not in contact with the ground, the four wheels, namely the pair of front wheels 5, each of which is a swivel, and the pair of swivel wheels 25 of the wheelchair training wheels 1, are in contact with the ground surface 85. In this state, the caregiver can move the wheelchair 2 in any direction, including sideways (widthwise). Therefore, even when there is not enough space to move forward or backward, such as at a bedside, the caregiver can easily move the wheelchair 2 to the side.

On the other hand, when lowering the rear wheels 4 of the wheelchair 2 to make contact with the ground and raising the swivel wheels 25 to make them non-contact with the ground, the attendant presses down on the unlocking pedal 53 of the wheelchair training wheels 1.

When the caregiver depresses the unlocking pedal 53 provided at the other longitudinal end (rear end) of the locking link member 47, as shown in Figures 11(B) and 11(C), the locking link member 47 pivots around the third pivot 50, with its other longitudinal end facing downward and forward, and its one longitudinal end (front end) facing upward and rearward, i.e., clockwise in Figures 11(B) and 11(C). When the locking link member 47 pivots, the engagement notch 52 provided at one longitudinal end of the locking link member 47 disengages from the second pivot 49. This allows the extension/retraction member 37 to extend its entire length (the lock is released).

When the lock on the extension and contraction of the entire length of the extension member 37 is released, as shown in Figure 11(C) → Figure 11(A), the elastic restoring force of the torsion coil spring 36 and the tension spring provided in the extension member 37 causes the first link member 45 and the second link member 46 to swing while contracting the entire length.

When a caregiver in a wheelchair 2 equipped with the wheelchair training wheels 1 of this example steps on the unlocking pedal 53 of the wheelchair training wheels 1 to contract the entire length of the extendable member 37, the first frame portion 21 supported by the frame 3 of the wheelchair 2 first descends, while the second frame portion 22 supporting the pair of swivel wheels 25 remains in place. Then, the pair of rear wheels 4 supported by the frame 3 come into contact with the ground surface 85.

When the entire length of the expandable member 37 further contracts from the state in which the pair of rear wheels 4 are in contact with the ground, the second frame portion 22 rises relative to the first frame portion 21 while the first frame portion 21 remains in its current position, and the pair of swivel wheels 25 supported by the second frame portion 22 move away from the ground surface 85 (entering a non-grounded state).

When the pair of swivel wheels 25 are not in contact with the ground, the pair of rear wheels 4 and the pair of front wheels 5 of the wheelchair 2 are in contact with the ground surface 85, and the wheelchair can be operated in the same way as a normal self-propelled wheelchair. That is, for example, the occupant can move or change direction of the wheelchair 2 by operating the hand rims 20. Furthermore, when the pair of swivel wheels 25 are not in contact with the ground, the elasticity of the torsion coil spring 36 and the tension spring provided in the expansion member 37 prevents the second frame portion 22 from descending (falling) relative to the first frame portion 21.

As described above, the wheelchair training wheels 1 of this example, which enable the wheelchair 2 to move in any direction, are detachably attached to the frame 3 of the wheelchair 2. Therefore, when storing or transporting the wheelchair 2, the wheelchair training wheels 1 can be removed from the frame 3 of the wheelchair 2, and the wheelchair 2 can be folded so that the pair of rear wheels 4 are closer together in the width direction, as shown in Figure 12.

In this example, the wheelchair training wheels 1 are detachably attached to the frame 3 of the wheelchair 2 at a location that coincides with the rear wheel axles 54 of the rear wheels 4 in the fore-and-aft direction; specifically, to the rear vertical member 8. In other words, in this example, the wheelchair training wheels 1 for raising and lowering the rear wheels 4 are attached to the rear vertical member 8, the portion of the frame 3 that bears the greatest weight of the occupant. This allows the line of action of the force applied from the wheelchair training wheels 1 to the frame 3 when raising and lowering the rear wheels 4 to be positioned substantially on the same line as the line of action of the load based on the occupant's weight. This reduces the strain on the frame 3 compared to when the wheelchair training wheels 1 are attached to a location other than the rear vertical member 8 on the frame 3. Furthermore, even when an assistant holds the handgrip 14 and operates the wheelchair 2 from behind with the wheelchair training wheels 1 attached to the frame 3, the wheelchair training wheels 1 are unlikely to interfere with the assistant's walking.

In addition, in this example, the first frame portion 21 and the second frame portion 22 are combined by a pair of linear guides 23, allowing for relative vertical displacement. This allows for moments to be supported in all directions, allowing the pair of rear wheels 4 to be raised and lowered stably.

The structure of the wheelchair 2 to which the wheelchair training wheel 1 of this example is detachably attached is not limited to the example described above, and any structure can be adopted. For example, the wheelchair training wheel 1 of this example is not limited to being attached to a self-propelled wheelchair 2, but can also be attached to an assisted wheelchair whose rear wheels do not have hand rims.

In this example, when the caregiver depresses the pedal 51, the lifting device 24 for the wheelchair training wheels 1 fully raises the first frame 21 relative to the second frame 22, engaging the engagement notch 52 of the locking link member 47 with the second pivot 49, maintaining the pair of swivel wheels 25 in contact with the ground and the pair of rear wheels 4 off the ground. When the caregiver depresses the unlocking pedal 53, the engagement notch 52 disengages from the second pivot 49, causing the pair of swivel wheels 25 to rise and the pair of rear wheels 4 to contact the ground. However, when implementing the wheelchair training wheels of the present invention, the structure of the lifting device that vertically displaces the first and second frame parts relative to each other, including the locking mechanism and its release method that maintains the state in which the swivel wheels are on the ground and the pair of rear wheels are off the ground, is not particularly limited and can be any structure.

Although not shown, the wheelchair training wheels 1 and/or wheelchair 2 may be equipped with a braking device to prevent the wheelchair 2 from moving unintentionally even when the pair of swivel wheels 25 of the wheelchair training wheels 1 are in contact with the ground and the pair of rear wheels 4 of the wheelchair 2 are not in contact with the ground, and the caregiver is not holding the hand grips 14.

[Second Example of Embodiment]
A second embodiment of the present invention will be described with reference to Figures 13 to 22(B). The wheelchair training wheel 1a of this embodiment differs from the lifting device 24 of the wheelchair training wheel 1 of the first embodiment in the structure of the lifting device 24a that relatively displaces the first frame portion 21 and the second frame portion 22 in the vertical direction. Specifically, the lifting device 24a has an electric structure that uses an electric motor 61 as a power source to relatively displace the first frame portion 21a and the second frame portion 22 in the vertical direction. In this embodiment, the lifting device 24a includes the electric motor 61 and a feed screw mechanism 62.

The electric motor 61 has a motor housing 63, an output shaft 64 rotatably supported inside the motor housing 63, a stator supported and fixed inside the motor housing 63, and a rotor supported and fixed around the output shaft 64. The motor housing 63 is supported and fixed to the first beam member 26b on the rear side of the first frame portion 21 using a fixing block 65. In this example, the electric motor 61 also has a brake function inside the motor housing 63 that prevents rotation of the output shaft 64 regardless of external force when the motor is de-energized.

The feed screw mechanism 62 includes a ball nut 66, a ball screw shaft 67, and a number of balls (not shown). In other words, in this example, the feed screw mechanism 62 is configured as a ball-type feed screw mechanism.

The ball nut 66 has a cylindrical shape and a spiral outer diameter ball screw groove (female ball screw groove) on its inner circumferential surface. The cross-sectional groove shape (groove bottom shape) of the outer diameter ball screw groove is a gothic arch groove or a circular arc groove.

The ball nut 66 is rotatably supported by the first frame portion 21 via a support bracket 68. The support bracket 68 has a pair of beam-like portions 84, a pair of column-like portions 69, and a nut support portion 70.

The pair of beam portions 84 are arranged parallel to each other and spaced apart in the width direction so as to extend in the front-to-rear direction. The pair of beam portions 84 are supported and fixed to the pair of first beam members 26a, 26b that make up the first frame portion 21 so as to span between the first beam members 26a, 26b.

The pair of pillars 69 are arranged to extend vertically, and their upper ends are fixedly connected to the longitudinal middle (front-to-back middle) of the beam 84. In other words, each pillar 69 is configured to hang down (extend) downward from the longitudinal middle of the beam 84.

The nut support portion 70 is configured in a flat plate shape, with its front end fixedly connected to the lower ends of a pair of columnar portions 69. The ball nut 66 is rotatably supported on the nut support portion 70 by a radial rolling bearing 71, with its central axis facing up and down.

The ball nut 66 is rotatably connected to the output shaft 64 of the electric motor 61 via a connecting member 72. The connecting member 72 has a cylindrical portion 73 and a bottom plate portion 74 that closes the upper end of the cylindrical portion 73. The connecting member 72 is connected to the output shaft 64 of the electric motor 61 so that torque can be transmitted therethrough by non-circularly fitting the output shaft 64 of the electric motor 61 into an engaging hole 75 provided in the bottom plate portion 74. The connecting member 72 is also connected to the ball nut 66 so that torque can be transmitted therethrough by fitting and fixing a fitting surface portion 76 provided on the inner surface of the lower end of the cylindrical portion 73 to the upper end of the ball nut 66. In this way, the connecting member 72 connects the output shaft 64 and ball nut 66 so that torque can be transmitted therethrough.

The ball screw shaft 67 has a spiral inner diameter ball screw groove (male ball screw groove) 77 on the outer peripheral surface of its upper portion. The cross-sectional groove shape (groove bottom shape) of the inner diameter ball screw groove is a Gothic arch groove or a circular arc groove. The upper portion of the ball screw shaft 67 is inserted inside the ball nut 66 and is positioned coaxially with the ball nut 66, with the lower portion supported and fixed non-rotatably to the second connecting member 33 of the second frame portion 22.

The outer diameter ball screw groove of the ball nut 66 and the inner diameter ball screw groove 77 of the ball screw shaft 67 are arranged radially opposite each other, forming a spiral load path. Each ball is arranged to roll freely in the load path. The start and end points of the load path are connected by a circulation means. That is, balls that reach the end point of the load path are returned to the start point of the load path via the circulation means. The start and end points of the load path are switched depending on the direction of relative displacement (relative rotation direction) in the axial direction (up and down direction) between the ball nut 66 and the ball screw shaft 67. The circulation means can be composed of a circulation path formed on the inner surface of the ball nut, or a circulation component such as a top.

In this example, the wheelchair training wheels 1a also have a pair of first connecting members 27 that form the mounting portion, which are detachably attached to the frame 3 that forms the wheelchair 2 using mounting brackets 55.

Furthermore, in a wheelchair 2 equipped with the wheelchair training wheels 1a of this example, the swivel wheels 25 can be raised and lowered by energizing the electric motor 61. The power supply to the electric motor 61 can be turned on and off by an assistant operating a switch. The mounting location of the switch is not particularly limited, but it can be mounted, for example, on the handgrip 14 or in its vicinity.

That is, by driving the ball nut 66 to rotate in a predetermined direction using the electric motor 61, the ball screw shaft 67 is moved downward relative to the ball nut 66, as shown in Figures 22(A) and 22(B). When the ball screw shaft 67 is moved downward relative to the ball nut 66, the second frame part 22 supporting the ball screw shaft 67 first descends, while the first frame part 21, which is supported by the frame 3 of the wheelchair 2 and supports the ball nut 66, remains in its current position. Then, the pair of swivel wheels 25 supported by the second frame part 22 comes into contact with the ground surface 85.

When the ball screw shaft 67 is further moved downward relative to the ball nut 66 from the state in which the pair of swivel wheels 25 are in contact with the ground, the first frame section 21 rises relative to the second frame section 22 while the second frame section 22 remains in its current position, and the rear portion of the frame 3 of the wheelchair 2 is raised higher than the front portion. As a result, the pair of front wheels 5 remain in contact with the ground surface 85, while the pair of rear wheels 4 move away from the ground surface 85 (becoming in a non-grounded state). When power to the electric motor 61 is stopped in this state, the brake mechanism provided in the electric motor 61 prevents rotation of the output shaft 64, and therefore rotation of the ball nut 66. This prevents axial (vertical) movement of the ball screw shaft 67 relative to the ball nut 66, maintaining the state in which the pair of swivel wheels 25 are in contact with the ground and the pair of rear wheels 4 are not in contact with the ground.

When the pair of rear wheels 4 are not in contact with the ground, the four wheels, namely the pair of front wheels 5, each of which is made up of swivel wheels, and the pair of swivel wheels 25 of the wheelchair training wheels 1a , are in contact with the ground surface 85, so the attendant can move the wheelchair 2 in any direction, including sideways (widthwise).

On the other hand, when the rear wheels 4 of the wheelchair 2 are lowered to make contact with the ground and the swivel wheels 25 are raised to make a non-contact state, the electric motor 61 rotates the ball nut 66 in the direction opposite to the predetermined direction, causing the ball screw shaft 67 to move upward relative to the ball nut 66, as shown in Figure 22(B) → Figure 22(A). Note that when the ball screw shaft 67 moves upward relative to the ball nut 66, the upper end of the ball screw shaft 67 is inserted inside the cylindrical portion 73 of the connecting member 72, allowing the ball screw shaft 67 to move upward relative to the ball nut 66.

When the ball screw shaft 67 is moved upward relative to the ball nut 66, the first frame portion 21 supported by the frame 3 of the wheelchair 2 first descends, while the second frame portion 22 supporting the pair of swivel wheels 25 remains in place. Then, the pair of rear wheels 4 supported by the frame 3 come into contact with the ground surface 85.

When the ball screw shaft 67 is further moved upward relative to the ball nut 66 while the pair of rear wheels 4 are in contact with the ground, the second frame portion 22 rises relative to the first frame portion 21 while the first frame portion 21 remains in its current position, and the pair of swivel wheels 25 supported by the second frame portion 22 move away from the ground surface 85 (entering a non-contact state).

When the pair of swivel wheels 25 are not in contact with the ground, the pair of rear wheels 4 and the pair of front wheels 5 of the wheelchair 2 are in contact with the ground surface 85, and the wheelchair can be operated in the same way as a normal self-propelled wheelchair.

In this example, the wheelchair training wheels 1a are also detachably attached to the frame 3 of the wheelchair 2, so that when storing or transporting the wheelchair 2, the wheelchair training wheels 1a can be removed from the frame 3 of the wheelchair 2, and the wheelchair 2 can be folded so that the pair of rear wheels 4 are closer together in the width direction, as shown in Figure 12.

Furthermore, the wheelchair training wheels 1a of this example prevent the occupant from receiving any shock when the pair of rear wheels 4 of the wheelchair 2 are switched from a non-ground-contact state to a ground-contact state.

In other words, with the wheelchair training wheels 1 according to the first embodiment, when the unlocking pedal 53 is depressed to disengage the engagement notch 52 from the second pivot 49, the weight of the wheelchair 2 and the weight of the occupant causes the first frame 21 to move forcefully downward (fall) relative to the second frame 22. As a result, the pair of rear wheels 4 may land forcefully on the ground 85, potentially causing an impact to the occupant.

In contrast, in the wheelchair training wheels 1a of this example, the swivel wheels 25 are raised and lowered by an elevating device 24a having an electric motor 61 and a feed screw mechanism 62. Therefore, the relative speed of vertical movement between the first frame portion 21 and the second frame portion 22 can be set to any speed. Therefore, when the first frame portion 21 is lowered relative to the second frame portion 22 to bring the pair of rear wheels 4 into contact with the ground, the pair of rear wheels 4 can be prevented from hitting the ground surface 85 with force, preventing an impact load from being applied to the occupant.

In this example, the ball nut 66 is rotatably supported relative to the first frame portion 21, and the ball screw shaft 67 is non-rotatably supported relative to the second frame portion 22. However, when implementing the present invention, the ball nut can be non-rotatably supported relative to the first frame portion, and the ball screw shaft can be rotatably supported relative to the second frame portion. Alternatively, the ball nut can be rotatably or non-rotatably supported relative to the second frame portion, and the ball screw shaft can be rotatably or non-rotatably supported relative to the first frame portion.

In this example, in order to maintain the vertical position of the second frame portion 22 relative to the first frame portion 21 when power is cut off, the electric motor 61 has a brake function that prevents rotation of the output shaft 64 when power is cut off. However, this is not limited to this configuration, and any other configuration can be used when implementing the present invention. For example, a reverse input cut-off clutch can be provided between the electric motor and the ball nut or ball screw shaft, which transmits torque from the electric motor to the ball nut or ball screw shaft but does not transmit torque from the ball nut or ball screw shaft to the electric motor.

In addition, in this example, the feed screw mechanism 62 uses a ball-type feed screw mechanism in which multiple balls are arranged between an outer diameter ball screw groove on the inner surface of the ball nut 66 and an inner diameter ball screw groove 77 on the outer surface of the ball screw shaft 67. However, when implementing the present invention, a sliding-type feed screw mechanism in which a female screw groove on the inner surface of the nut and a male screw groove on the outer surface of the screw shaft are in direct sliding contact can also be used. In this case, the brake function of the electric motor and the reverse input cut-off clutch may be omitted. The configuration and effects of other parts are the same as those of the first embodiment.

REFERENCE SIGNS LIST 1, 1a Wheelchair training wheel 2 Wheelchair 3 Frame 4 Rear wheel 5 Front wheel 6 Side part 7 Cross pipe 8 Rear vertical member 9 Front vertical member 10 Upper horizontal member 11 Lower horizontal member 12 Pillar portion 13 Bending portion 14 Hand grip 15 Bending portion 16 Foot support 17 Tipping lever 18 Link member 19 Seat support member 20 Hand rim
21 First frame portion 22 Second frame portion 23 Linear guide 24, 24a Elevating device 25 Swivel wheel 26a, 26b First beam member 27 First connecting member 28 First columnar member 29 Notch 30 Second columnar member 31 Second beam member 32 Hanging member 33 Second connecting member 34 Guide rail 35 Slider 36 Torsion coil spring 37 Expandable member 38 Link mechanism 39 First member 40 Second member 41 First support plate portion 42 First cylindrical portion 43 Second support plate portion 44 Second cylindrical portion 45 First link member 46 Second link member 47 Locking link member 48 First pivot 49 Second pivot 50 Third pivot 51 Pedal portion 52 Engagement notch portion 53 Unlocking pedal portion 54 Rear wheel axle 55 Mounting bracket 56 Bracket body 57 Mounting screw 58 Side plate portion 59 Bent plate portion 60 Clamp handle 61 Electric motor 62 Feed screw mechanism 63 Motor housing 64 Output shaft 65 Fixed block 66 Ball nut 67 Ball screw shaft 68 Support bracket 69 Column portion 70 Nut support portion 71 Radial rolling bearing 72 Connecting member 73 Cylindrical portion 74 Bottom plate portion 75 Engagement hole 76 Fitting surface portion 77 Inner diameter side ball screw groove 78 Seat 79 Mounting plate 80 Wheel support portion 81 Wheel 82 Support plate portion 83 Connecting portion
84 Beam-like part 85 Ground plane

Claims (7)

a first frame portion having an attachment portion that is detachably attached to a frame of a wheelchair;
a second frame portion supported so as to be movable up and down relative to the first frame portion;
an elevator device that raises and lowers the second frame portion relative to the first frame portion;
a swivel supported by the second frame portion so as to be rotatable about a vertically disposed pivot axis;
Equipped with
The lifting device comprises a link mechanism having a first link member, the end of which on one side in the length direction is supported relative to the first frame portion or a member supported and fixed to the first frame portion so as to be swingable about a first pivot axis arranged in the width direction, and a second link member, the end of which on one side in the length direction is supported relative to the end of the other side in the length direction of the first link member so as to be swingable about a second pivot axis arranged in the width direction, and the intermediate portion in the length direction is supported relative to the second frame portion or a member supported and fixed to the second frame portion so as to be swingable about a third pivot axis arranged in the width direction.
Wheelchair training wheels. a linear guide that supports the second frame portion so that the second frame portion can be raised and lowered relative to the first frame portion;
2. The wheelchair training wheel according to claim 1. the lifting device includes a locking mechanism that prevents the second frame portion from rising relative to the first frame portion when the second frame portion is lowered relative to the first frame portion.
3. The wheelchair training wheel according to claim 1 or 2. A plurality of the swivel wheels are provided.
The wheelchair training wheel according to any one of claims 1 to 3. the second link member has a pedal portion at the other end in the length direction;
The wheelchair training wheel according to any one of claims 1 to 4 . The mounting portion is detachably attached to a portion of the frame that coincides with a rotation axis of a rear wheel that constitutes the wheelchair in the front-rear direction.
The wheelchair training wheel according to any one of claims 1 to 5 . The frame and
a pair of rear wheels supported on the frame so as to be rotatable only about rear wheel axes disposed horizontally;
a front wheel supported on the frame so as to be able to rotate about a front wheel side pivot shaft disposed in a vertical direction and a front wheel shaft disposed in a horizontal direction;
a wheelchair training wheel detachably attached to the frame;
Equipped with
The wheelchair training wheel is the wheelchair training wheel according to any one of claims 1 to 6 .
Wheelchair with training wheels.