JP6464221B2 - wheelchair - Google Patents

Description

  The present invention relates to a wheelchair. More specifically, the present invention relates to a wheelchair that can mitigate and attenuate vibrations and shocks transmitted from the road surface during traveling without impairing the original traveling function of the wheelchair and without the addition of a vibration or shock absorbing structure such as a suspension. About.

  For example, as shown in FIGS. 20 (a) and 20 (b), a general wheelchair passes a seating surface between a pair of strong side frames, and each side frame has a small front wheel (steering caster). And a large-diameter rear wheel (main wheel) are rigidly fixed. Therefore, for example, when traveling with a wheelchair, vibrations and / or impacts transmitted from the road surface via wheels are hardly absorbed (except for absorption by a seat surface, which is generally made of cloth), and directly to the occupant. It is transmitted.

  Such vibrations and / or shocks are not only uncomfortable for wheelchair occupants, but depending on the illness and / or disability of the occupant, they may feel pain due to slight vibrations or It may be difficult to maintain. Such a problem becomes particularly noticeable when traveling on an uneven surface. In addition, such a problem occurs regardless of whether the wheelchair is a fixed type or a foldable type. Regardless of whether it is a running type, it is a common issue.

  In response to the above problems, many techniques have been proposed for mitigating vibration and shock transmitted from the road surface by installing a vibration / shock absorbing structure such as a so-called “suspension” on a wheelchair (for example, Patent Documents 1 to 4). 3). However, the addition of the vibration / shock absorbing structure as described above may increase the weight of the wheelchair, increase the complexity and size of the structure, increase the manufacturing cost, and require periodic maintenance. However, wheelchairs having such a vibration / shock absorbing structure have not been widely used.

  Therefore, in this technical field, attempts have been made to absorb the impact on the wheelchair frame itself without providing suspensions (see, for example, Patent Document 4). According to this, for example, a substantially C-shaped open structure (for example, as shown in FIG. 20B) is formed by cutting out a part of a side frame having a closed structure. Hereinafter, it may be referred to as a “cantilever structure”), and the side frame rigidity is intentionally lowered to induce bending. Then, the seat surface is passed between the upper parts of a pair of such side frames, and the front and rear wheels are attached to the lower parts of these side frames, and the substantially C-shaped side frame bends in the vertical direction so that the road surface Absorbs vibrations and shocks transmitted from

  According to the above structure, the vibration and impact transmitted from the road surface can be relaxed and attenuated. However, when the wheelchair travels, movements (acceleration) in various directions as well as the vertical direction act on the wheelchair. In addition, the center of gravity moves due to a change in the posture of the occupant due to a reaction force acting on the occupant himself when the occupant drives (rows) the rear wheel. As a result, in addition to vertical deflection, the upper side of the side frame is tilted to the left and right (bank), swings to the left and right with respect to the direction of travel (yaw), and up and down with respect to the direction of travel. Triaxial deflections and / or twists can also occur, such as movement (pitch), such as shaking (bowing or supine).

  As a result, not only does the occupant feel significant discomfort, but the mutual alignment of the four wheels and the center of gravity of the wheelchair constantly change, making it difficult or unintentional to advance the wheelchair in the intended direction. There is a risk of the wheelchair traveling in the direction.

Japanese Patent No. 3463013 Japanese Patent No. 4264718 JP 2006-110030 A JP 2005-143774 A Utility Model Registration No. 31777781 Japanese Patent No. 3613215

  As described above, in this technical field, vibration and impact transmitted from the road surface during traveling are reduced / damped without impairing the original traveling function of the wheelchair and without adding vibration / shock absorbing structure such as suspension. There is an ongoing need for wheelchairs that can do. The present invention has been made to meet such a demand.

In view of the above, a wheelchair according to the present invention (hereinafter sometimes referred to as “the wheelchair of the present invention”) has a seat portion between a pair of side frames connected by at least one pair of cross frames. It is a wheelchair.
Each of the pair of side frames is formed in a part thereof, a bending portion whose curvature can be changed by elastic deformation, an upper frame located above the bending portion, and a position below the bending portion. A lower frame is provided.
On the other hand, the cross frame is constituted by a pair of arms that are pivotally supported by one pivot so as to be mutually rotatable.
Further, the upper frame of each of the pair of side frames is an upper arm that is a portion above the pivot of the arm of the cross frame via a connecting member rotatably supported by the upper frame. Is pivotally supported.
In addition, the lower frame of each of the pair of side frames rotatably supports a lower end of a lower arm, which is a lower part of the pivot of the arm of the cross frame, and also includes a front wheel caster and a rear wheel. The main shaft of the wheel is installed.

  With the above configuration, the wheelchair of the present invention can relieve / attenuate vibration and impact transmitted from the road surface via the front and rear wheels during traveling by elastic deformation of the curved portion provided in the middle of the side frame. As a result, according to the wheelchair of the present invention, vibration and impact transmitted from the road surface during traveling can be mitigated and attenuated without adding a vibration / impact absorbing structure such as a suspension.

  Furthermore, in the wheelchair of the present invention, the pair of side frames are connected to each other by the cross frame and the connecting member. As a result, according to the wheelchair of the present invention, an unintended change occurs in the alignment of the four wheels, and the occupant feels a lot of discomfort or makes it difficult to advance the wheelchair in the intended direction. It is possible to reduce the possibility that the wheelchair travels in the direction not to go.

  Other objects, other features, and attendant advantages of the present invention will be readily understood from the description of each embodiment of the present invention described with reference to the following drawings.

It is a typical perspective view which shows the structure at the time of extension (a) and folding (b) of the wheelchair which concerns on one Example of this invention (Example wheelchair). FIG. 2 is a schematic front view (a), left side view (b), rear view (c), top view (d), and bottom view (e) of the embodiment wheelchair shown in FIG. 1. It is a typical perspective view which shows the detail of the cross frame with which an Example wheelchair is provided, and a connection member. It is typical sectional drawing (AA sectional drawing) by line AA shown in the bottom view (e) of FIG. (A) Bottom view schematically showing a state in which the front wheel caster and the footrest part are set at a position closest to the occupant in the wheelchair of the embodiment, (b) a sectional view taken along line AA shown in (a) above, And (c) is an enlarged view of a portion where the front wheel caster and the footrest portion are fixed to the subframe in (b). (A) Schematic (a) bottom view showing a state in which the front wheel caster and the footrest part are set at a position farthest from the occupant in the wheelchair of the embodiment, (b) a sectional view taken along line AA shown in (a) above, And (c) is an enlarged view of a portion where the front wheel caster and the footrest portion are fixed to the subframe in (b). It is a typical front view which shows the positional relationship of the pivot of a cross frame and the main axis | shaft of a rear wheel in an Example wheelchair. It is typical (a) front view of the cross frame in the Example wheelchair at the time of extension, (b) Top view, (c) Left side view. It is typical (a) front view of the cross frame in the Example wheelchair at the time of folding, (b) Top view, (c) Left view. It is a schematic diagram explaining a mode that the position of the footrest comprised with the plate-shaped member is adjusted. FIG. 4 is a schematic top view (a) and a right side view (b) of a wheelchair according to a second embodiment of the present invention (second embodiment wheelchair), and is drawn as a perspective view for the purpose of helping understanding of the configuration. It is. FIG. 11 is a schematic cross-sectional view (a) illustrating a state in which the footrest portion and the sleeve of the wheelchair of the second embodiment illustrated in FIG. 11 are coupled by a ball joint, and a schematic enlarged cross-sectional view in the vicinity of the ball joint (b). is there. It is a schematic diagram which shows a mode that the front wheel caster of a wheelchair and a rear wheel (main wheel) descend | fall from the said level | step difference after riding on the level | step difference provided artificially. It is a typical graph which shows the time-dependent change of the acceleration measured by the acceleration sensor with which the axle of the footrest and the front-wheel caster was mounted | worn in the driving test of the conventional wheelchair. It is a typical graph which shows the time-dependent change of the acceleration measured by the acceleration sensor with which the axle | axis of the footrest and the front wheel caster was mounted | worn in the running test of the wheelchair of 2nd Example. It is a typical perspective view which shows the external appearance of a 2nd Example wheelchair. It is a typical perspective view which shows the external appearance of the wheelchair (3rd Example wheelchair) which concerns on 3rd Example of this invention. It is a typical perspective view which shows the external appearance of the exterior cover with which a 3rd Example wheelchair is provided. FIG. 6 is six views (a) to (f) and isometric views (isometric views) (g) and (h) showing the structure of an exterior cover mounted on the right side frame of the wheelchair of the third embodiment. It is a schematic diagram which shows the structural example of the wheelchair which concerns on a prior art (conventional wheelchair).

<< First Embodiment >>
Hereinafter, the wheelchair according to the first embodiment of the present invention (hereinafter, may be referred to as “first wheelchair”) will be described.

<Constitution>
The first wheelchair is a wheelchair having a seat portion between a pair of side frames connected by at least one pair of cross frames. The first wheelchair may be a fixed type or a foldable type, and even if it is an assisting type pushed by an assistant or the like, the seated person is self-propelled (driving the rear wheel) by itself. There may be.

  Each of the pair of side frames includes a curved portion that is formed at a part of the pair of side frames and can change a curvature by elastic deformation, an upper frame that is located above the curved portion, and a lower portion that is located below the curved portion. Provide a frame. The curved portion, the upper frame, and the lower frame may be formed as separate members, and may be joined to each other by a method such as fitting, welding, or bonding to form a side frame. Alternatively, the curved portion, the upper frame, and the lower frame may be integrally formed to constitute a side frame.

  The bending portion is formed between the upper frame and the lower frame, and is configured such that its curvature can be reversibly changed by elastic deformation. The elastic deformation characteristics of the bending portion can reduce or attenuate the vibration and impact transmitted from the road surface during traveling by adjusting the mechanical strength and thickness of the material constituting the bending portion, the thickness and curvature of the bending portion, for example. It can be made suitable for.

  The configuration of the bending portion is not limited to the above as long as it can absorb and mitigate up-down vibration and impact (input) transmitted from the road surface during travel by elastic deformation between the upper frame and the lower frame. .

  By the way, the side frame may further include a back frame that is a member for forming a backrest by a sheet-like member stretched between them, on the upper side of the upper frame. Further, the side frame may include a handle portion that is a member for an assistant to operate the wheelchair in addition to the back frame or instead of the back frame.

  The cross frame includes a pair of arms that are pivotally supported by one pivot so as to be rotatable relative to each other. The side frame is pivoted by a cross frame (sometimes referred to as “cross brace” or the like) and a connecting member that assists the cross frame (sometimes referred to as “link member” or “connecting bar”). The supporting structure is generally used in a wheelchair (see, for example, Patent Document 5).

  Typically, arms made of two bent pipe-like members are crossed, and at the crossing portions, the two arms are pivotally supported by a pivot so as to be mutually rotatable. The lower end of the cross frame (the lower end of each arm) is pivotally supported by the lower frame of the side frame so as to be rotatable (rotatable). A seat frame for stretching a sheet-like member (for example, cloth) for forming a seating surface is fixed (for example, by welding) to the upper end of the cross frame (the upper end of each arm).

  In the first wheelchair, the upper frame of each of the pair of side frames is a portion above the pivot of the arm of the cross frame via a connecting member rotatably supported by the upper frame. The upper arm is pivotally supported. Specifically, as will be described in detail in the embodiments to be described later, one end of each connecting member can be rotated relative to each other at a portion slightly below the upper ends of a pair of arms constituting the cross frame (relatively rotatable). ). The other end of the connecting member is pivotally supported by the upper frame so as to be mutually rotatable (relatively rotatable). On the other hand, the lower frame of each of the pair of side frames rotatably supports the lower end of the lower arm, which is a lower part of the pivot of the arm of the cross frame.

  In the first wheelchair, the vibration and impact transmitted from the road surface through the front wheels and the rear wheels during traveling are mitigated and attenuated by the structure in which the pair of side frames are connected by the cross frame and the connecting member as described above. At this time, due to the positioning effect by the cross frame, only the relative movement in the vertical direction is allowed between the upper frame and the lower frame, and the movements such as the three-axis bending and / or twisting as described above are prevented. Therefore, vibration and impact transmitted from the road surface during traveling can be reliably absorbed and mitigated by elastic deformation of the curved portion provided in the middle of the side frame. Such an effect corresponds to a dynamic positioning function of the lateral rod in the suspension of the automobile.

  In addition, the cross frame opens and closes with the relative movement of the upper and lower frames in the vertical direction (two arms rotate around the pivot), so that the seat stretched between the left and right seat frames The tension acting on the surface (for example, a sheet-like member such as cloth) changes. Since the occupant sits on the seat surface, the opening and closing of the cross frame can be attenuated and / or stopped by the expansion and contraction of the seat surface and the weight (inertial weight) of the occupant. That is, in the first wheelchair, the above structure can be made to function as a vibration damping mechanism that exhibits a damping function and / or a stopper function of vibration and impact transmitted from the road surface during traveling. Such an effect corresponds to a function of a combination of a spring and a shock absorber in the suspension of an automobile.

  Further, a front wheel caster and a rear wheel main shaft are mounted on the lower frame. The method of mounting the front wheel casters and the rear wheel main shafts to the lower frame is not particularly limited as long as vibration and impact transmitted from the road surface through the front wheels and the rear wheels are transmitted to the lower frame during traveling. That is, the front wheel casters and the rear wheel main shafts may be directly mounted on the lower frame or indirectly mounted on the lower frame via other members. Since the front wheel caster and the rear wheel are well known to those skilled in the art, a detailed description thereof is omitted here.

<Effect>
With the above configuration, the first wheelchair can relieve / attenuate vibration and impact transmitted from the road surface via the front and rear wheels during traveling by elastic deformation of the curved portion provided in the middle of the side frame. As a result, according to the first wheelchair, vibrations and shocks transmitted from the road surface during traveling can be reliably mitigated and attenuated without adding a vibration / shock absorbing structure such as a suspension.

  Furthermore, in the first wheelchair, the pair of side frames are connected to each other by a cross frame and a connecting member. As a result, according to the first wheelchair, an unintended change occurs in the alignment of the four wheels, and the occupant feels significant discomfort or makes it difficult to move the wheelchair in the intended direction. It is possible to reduce the possibility that the wheelchair travels in the direction not to go.

<< Second Embodiment >>
Hereinafter, a wheelchair according to a second embodiment of the present invention (hereinafter may be referred to as a “second wheelchair”) will be described.

<Constitution>
The second wheelchair is the first wheelchair described above, and each of the pair of side frames is formed of an integral hollow pipe, and the upper frame, the curved portion, and the lower frame that are continuous are directed rearward. An open U-shape is formed.

<Effect>
As described above, in the second wheelchair, each of the pair of side frames has a U-shaped shape in which the upper frame, the curved portion, and the lower frame are opened rearward by an integral hollow pipe. It is integrally formed. As a result, according to the second wheelchair, it is possible to reduce the weight of the wheelchair and reduce the manufacturing cost.

<< Third Embodiment >>
Hereinafter, a wheelchair according to a third embodiment of the present invention (hereinafter may be referred to as a “third wheelchair”) will be described.

  As described above, when vibration and impact transmitted from the road surface are input during traveling, the cross frame opens and closes as the upper frame and the lower frame move relative to each other (the two arms rotate around the pivot axis). Move). Strictly speaking, the main shaft of the rear wheel rotates around the pivot axis of the cross frame.

  Thus, for example, if the rear wheel main shaft is located at a position lower than the pivot, and there is a thrust from the road surface, the left and right rear wheel main shafts are separated from each other (the camber angle of the left and right rear wheels). The sub-frame tries to move in the direction of increasing. Conversely, if there is a thrust from the road surface with the rear wheel main shaft positioned higher than the pivot, the direction of the left and right rear wheel main shaft approaching around the pivot (the camber angle of the left and right rear wheels is The subframe tries to move in the increasing direction. That is, there is a possibility that relative movement other than the vertical direction occurs between the upper frame and the lower frame.

  As described above, when the height of the pivot of the cross frame and the height of the main shafts of the left and right rear wheels do not match, only the relative movement in the vertical direction is allowed between the upper frame and the lower frame as described above. Thus, there is a possibility that the “positioning effect by the cross frame” that prevents the movements such as the bending and / or twisting of the three axes is weakened.

<Constitution>
Therefore, the third wheelchair is the first wheelchair or the second wheelchair described above, and in the free state in which an external load is not applied to the seat portion of the wheelchair in the form in use, the cross The radial direction and the width direction of the left and right rear wheels with respect to a plane including the pivot axis of the frame and a horizontal straight line perpendicular to the axis (hereinafter sometimes referred to as a “pivot plane”) The centers in both directions (hereinafter sometimes referred to as “rear wheel centers”) are arranged so as to be on the lower side in the vertical direction.

<Effect>
Even in the third wheelchair in which the positional relationship between the pivot plane and the center of the rear wheel is defined as described above, strictly speaking, the main axis of the rear wheel rotates around the pivot axis of the cross frame. However, in the third wheelchair, the left and right rear wheel centers are disposed on the lower side (road surface side) with respect to the pivot plane in the free state as described above. With this initial arrangement, when the occupant sits on the seat, the seat sinks due to the weight of the occupant, the cross frame opens, and the pivot plane approaches the center of the rear wheel. Ideally, when the occupant sits on the seat, the pivot of the cross frame and the main shafts of the left and right rear wheels have the same ground height. At this time, the direction of the tangent to the main shaft of the left and right rear wheels of the circle centering on the pivot and passing through the main shaft of the left and right rear wheels is the vertical direction (vertical direction).

  That is, according to the third wheelchair, only relative movement in the vertical direction is allowed between the upper frame and the lower frame, and movement such as triaxial bending and / or twisting can be prevented. In other words, the third wheelchair can be sufficiently exerted without impairing the “positioning effect by the cross frame” as described above.

<< 4th Embodiment >>
The wheelchair according to the fourth embodiment of the present invention (hereinafter may be referred to as “fourth wheelchair”) will be described below.

  As described above, a seat occupant sits on a seat-like member such as a cloth that is stretched between seat frames fixed to the upper end (the upper end of each arm) of the cross frame (for example, by welding). A seating surface can be formed. However, in a wheelchair according to the prior art (hereinafter sometimes referred to as “conventional wheelchair”), for example, a linear seat frame is used as shown in FIG. Therefore, the seating surface formed between them also has a planar shape (shaded portion), and it is difficult to sufficiently maintain (support) the sitting position (sitting posture) of the occupant.

  In particular, in the case of a seated person who has a disability such as inferiority of the lower body, correct the posture by his / her own will even if the posture of the seated person changes to an inappropriate state during driving (during driving or moving) Is difficult. When such a seated person sits for a long time without being able to hold a proper sitting position, for example, viscera due to fatigue, lower body congestion, floor rubbing, spinal curvature and poor blood flow There is a risk of secondary disorders such as diseases. For this reason, it is very important to sufficiently maintain the sitting position (sitting position) of the occupant.

<Constitution>
Therefore, in the fourth wheelchair, the wheelchair is any one of the first to third wheelchairs described above, and a seat frame that is a non-linear member is provided at the upper ends of the pair of upper arms of the cross frame. The seat surface of the seat is formed by a sheet-like member that is fixed to each other and stretched between the two seat frames.

<Effect>
As described above, in the fourth wheelchair, the seat surface of the seat is formed by the sheet-like member stretched between the non-linear seat frames. Accordingly, the seating surface can be formed as a curved surface that is not a simple plane. For example, when the fourth wheelchair is not folded (for example, when extended such as when traveling), in the region where the occupant's buttocks ride, the distance between the left and right seat frames is wide and close to the occupant's knee The shape of the seat frame can be determined so that the height of the left and right seat frames increases in the region. Thereby, a hip and a waist | hip | lumbar part when a seated person sat down are appropriately hold | maintained three-dimensionally, and a seated person's attitude | position can be stabilized. As a result, it is possible to reduce the possibility of a secondary failure resulting from the inability to maintain the appropriate sitting position as described above.

<< 5th Embodiment >>
The wheelchair according to the fifth embodiment of the present invention (hereinafter may be referred to as “fifth wheelchair”) will be described below.

  As described above, according to the fourth wheelchair, the seat surface of the seat portion is formed into a curved shape by the sheet-like member stretched between the non-linear seat portion frames, and the seated person sits down. It is possible to stabilize the posture of the seated occupant by appropriately holding the buttocks and the hips in three dimensions.

  However, when the non-linear seat frame is used in a folding wheelchair as described above, the left and right seat frames interfere with each other in a state in which the wheelchair is folded, and the wheelchair is folded sufficiently small. May be difficult.

<Constitution>
Therefore, the fifth wheelchair aims to achieve both a seat surface that can sufficiently hold the seated position of the occupant when unfolded and a seat frame in which the left and right seat frames do not interfere with each other when folded. Was conceived.

  Specifically, the fifth wheelchair is the above-described fourth wheelchair and a foldable wheelchair. That is, the fifth wheelchair rotates the pair of arms around the pivot so that the longitudinal direction of the pair of arms constituting the cross frame approaches the vertical direction, thereby reducing the distance between the pair of side frames. The volume occupied by the wheelchair can be reduced (compact).

  Furthermore, in the fifth wheelchair, the axis of the seat frame is two-dimensionally curved in one plane, and the axis of the two seat frames is in the folded state of the wheelchair. The seat frame is fixed to the upper ends of the pair of upper arms of the cross frame so that the two planes including them are parallel to each other.

<Effect>
For example, in the form of folding the fifth wheelchair, the left and right seat frame portions corresponding to the area on which the occupant's buttocks ride are bent upward in the vertical direction and the seat corresponding to the area close to the occupant's knee. The part frame portion (that is, the vicinity of the front end) is also curved upward in the vertical direction. In this configuration, the seat frame is only partially curved upward in the vertical direction, so the left and right seat frames may interfere with each other and it may be difficult to fold the wheelchair sufficiently small. Is reduced.

  On the other hand, when the fifth wheelchair is extended from the folded state, the arm rotates around the pivot of the cross frame to increase the distance between the left and right side frames. Accordingly, the distance between the left and right seat frames is also increased while rotating around the pivot. At this time, the bending direction of the seat frame also rotates from the folding direction (upward in the vertical direction) and approaches the outward direction in the width direction (left-right direction).

  As a result of the above, the fifth wheelchair also has a wide space between the left and right seat frame in the region where the occupant's buttocks ride in the unfolded form, as in the fourth wheelchair described above. The shape of the seat frame can be determined so that the height of the left and right seat frames increases in the region close to the knee. As a result, the hip and waist when the occupant is seated are appropriately held in three dimensions to stabilize the posture of the occupant and reduce the possibility of leading to secondary obstacles as described above. be able to.

  That is, according to the fifth wheelchair, both a seat surface that can sufficiently hold the seated position of the occupant when not folded and a seat frame in which the left and right seat frames do not interfere with each other when folded are achieved. Can do.

<< 6th Embodiment >>
The wheelchair according to the sixth embodiment of the present invention (hereinafter may be referred to as “sixth wheelchair”) will be described below.

<Constitution>
The sixth wheelchair is any one of the first to fifth wheelchairs described above, and a subframe that is a member extending forward is fixed to the lower frame of the side frame. The fixing method of the subframe to the lower frame is not particularly limited, and can be appropriately selected from various methods such as fastening (screwing) with bolts and nuts, fitting, welding, and adhesion.

  Further, in the sixth wheelchair, a sleeve is fixed to the sub-frame so as to be slidable in the front-rear direction, and a base portion of the front wheel caster is fixed to the sleeve. The method of fixing the sleeve to the subframe is not particularly limited. For example, when the subframe is constituted by a hollow pipe, the sleeve has a pipe shape having an outer diameter that can be slidably fitted inside the hollow pipe. Or it can comprise by a rod-shaped member. And, for example, by screwing a bolt inserted into a through-hole formed in the tube wall of the subframe into a screw hole (nut hole) formed in the sleeve, the sleeve can be slid in the front-rear direction. Can be fixed to.

  The method for fixing the base portion of the front wheel caster to the sleeve is also not particularly limited, and can be appropriately selected from various methods such as fastening (screwing) with bolts and nuts, fitting, welding, and adhesion. Alternatively, the base portion, the sleeve, and the subframe of the front wheel caster may be fixed together by, for example, joint fastening with bolts and nuts.

<Effect>
As described above, in the sixth wheelchair, the base portion of the front wheel caster is fixed to the sleeve fixed to the sub-frame fixed to the lower frame so as to be slidable in the front-rear direction. Therefore, according to the sixth wheelchair, for example, the position of the front wheel caster can be easily adjusted according to the position of the center of gravity of the wheelchair that differs depending on the physique and sitting posture of the occupant. In addition, for example, the stability of the wheelchair can be increased according to the posture when the occupant gets into the wheelchair, and the wheelchair can be prevented from falling over easily.

<< 7th Embodiment >>
The wheelchair according to the seventh embodiment of the present invention (hereinafter may be referred to as “seventh wheelchair”) will be described below.

  Incidentally, in a wheelchair according to the prior art (conventional wheelchair), for example, as shown in FIGS. 20A and 20B, a front wheel caster is attached to a member extending in a substantially vertical direction from the side frame. . In addition, a pair of footrests (footrests), which are members for the occupants to place their feet on, are members that extend in a substantially vertical direction from the side frame (same or different from the members to which the front wheel casters are attached). Many are attached and the position of the footrest can be adjusted only in a substantially vertical direction.

  Therefore, for example, when it is desired to move the footrest away from the occupant according to the physique (leg length, etc.) and / or the sitting posture of the occupant, there is no choice but to lower the height of the footrest. As a result, it may be difficult to secure the minimum ground clearance of the footrest, or the feet of the occupant may come into contact with the road surface (ground). In such a case, in order to ensure the minimum ground clearance of the footrest, it is necessary to increase the diameter of the front wheel.

  However, when the diameter of the front wheel is increased, the occupant's foot (for example, the heel) and the front wheel (caster) may contact and interfere with each other when the front wheel caster rotates, for example, when the wheelchair turns. In such a case, for example, a seated person who has no or little sense of the lower body, such as a seated person who has a disability such as inferiority of the lower body, is less likely to notice contact / interference between the foot and the front wheel. Repeatedly many times may lead to serious injury.

<Constitution>
Therefore, the seventh wheelchair is the sixth wheelchair described above, and the footrest portion is fixed to the sleeve. Here, the “footrest portion” refers to a portion including a footrest (footrest) and a member for attaching the footrest to the wheelchair.

<Effect>
As described above, in the seventh wheelchair, the footrest portion is fixed to the sleeve fixed to the subframe fixed to the lower frame so as to be slidable in the front-rear direction, similarly to the base portion of the front wheel caster. Therefore, the footrest and the front wheel caster can be moved integrally by sliding the sleeve with respect to the subframe. As a result, unlike the conventional wheelchair, the distance between the footrest and the front wheel caster becomes narrow, and the possibility of the contact / interference between the occupant's foot and the front wheel as described above can be reduced.

  Furthermore, in the seventh wheelchair, the footrest and the front wheel caster can be moved in the front-rear direction by sliding the sleeve in the front-rear direction (not in the vertical direction) with respect to the subframe. Therefore, it is possible to reduce the possibility that it is difficult to secure the minimum ground clearance of the footrest as in the case of a conventional wheelchair or that the foot of the occupant comes into contact with the road surface (ground).

  However, the wheelchair according to the present invention may be configured such that the attachment positions of the base portion of the front wheel caster and the footrest portion with respect to the sleeve can be independently adjusted. Further, in this case, a limit may be provided to the adjustable range of each position to reduce the possibility of contact / interference between the occupant's feet and the front wheels as described above.

<< Eighth Embodiment >>
The wheelchair according to the eighth embodiment of the present invention (hereinafter may be referred to as “eighth wheelchair”) will be described below.

  By the way, as described above, in the wheelchair according to the present invention including the various embodiments including the first to seventh embodiments (the wheelchair according to the present invention), vibration and impact transmitted from the road surface to the upper frame during traveling. Can be relaxed and attenuated by elastic deformation of the curved portion. As a result, according to the wheelchair of the present invention, vibration and impact transmitted from the road surface to the seat surface during traveling can be surely mitigated and attenuated without adding a vibration / impact absorbing structure such as a suspension.

  However, in the above-described seventh wheelchair, a footrest portion, which is a member for the occupant to place his / her foot, is fixed to the sleeve. The base of the front wheel caster is fixed to the sleeve. As a result, the seventh wheelchair cannot mitigate / attenuate vibrations and shocks transmitted from the road surface to the footrest portion through the front wheel caster during traveling. Therefore, depending on the traveling state of the wheelchair and / or the road surface condition, for example, vibration or impact transmitted from the road surface to the footrest part through the front wheel caster during traveling may cause the passenger to feel uncomfortable, May move on the footrest, and in some cases, the foot of the occupant may fall off the footrest.

  In this technical field, by providing a vibration / impact absorbing structure between a wheel and a member that supports the wheel, vibration and shock transmitted from the road surface to the main body of the wheelchair during traveling are reduced / damped. It is known. Specifically, it has been proposed to support a front wheel caster by a swing arm, or to provide a so-called “suspension” inside or outside the front wheel caster (see, for example, Patent Document 6). According to these, the impact of the up-down direction transmitted from the road surface to the main body of a wheelchair via a wheel can be buffered. However, the addition of the vibration / shock absorbing structure as described above may lead to problems such as a complicated wheelchair structure and / or an increase in manufacturing cost.

  In addition, when the occupant drives the rear wheel (main wheel) in a situation where a large driving force is required for the wheelchair, such as when starting and sudden acceleration, the occupant tilts the upper body forward. In some cases, the center of gravity is moved forward, and the hand rim is pushed while the body weight is placed on the arm, and the rear wheel is pushed. However, since the stroke of the vibration / shock absorbing structure as described above is generally large, in the wheelchair that supports the front wheel caster by such a structure, the front wheel side of the wheelchair sinks with the movement of the center of gravity of the occupant, There is a risk that it will be difficult for the occupant to push the hand rim while rowing his / her own weight on his / her arm and row the rear wheel.

  Further, in view of recent road conditions, vibrations and impacts transmitted from the road surface to the footrest part through the front wheel casters during traveling may cause rough asphalt surfaces such as permeable pavement and drainage pavement, bricks and / or concrete blocks. Often there are fine vibrations and shocks with small amplitudes and short periods due to rough interlocking blocks such as spread interlocking blocking and gratings.

<Constitution>
Therefore, the eighth wheelchair is the seventh wheelchair described above, and the footrest portion is fixed to the sleeve so as to be movable within a predetermined range, and the footrest portion and the subframe and / or A cushioning material is interposed between the sleeve. That is, in the eighth wheelchair, the footrest portion is loosely fixed to the sleeve, and between the footrest portion and the subframe, between the footrest portion and the sleeve, or between the footrest portion and the subframe, and A cushioning material is interposed between the footrest portion and the sleeve. As long as such a requirement is satisfied, the specific coupling mode between the footrest portion and the subframe and / or the sleeve is not particularly limited.

  For example, when a cushioning material is interposed between the footrest portion and the subframe, the footrest portion is movable so as to be movable within a predetermined range (for example, slidable, swingable and / or movable). A cushioning material may be interposed between the footrest portion and the subframe so as to be loosely fixed to the sleeve and to narrow the movable range of the footrest portion.

  Furthermore, when a cushioning material is interposed between the footrest portion and the sleeve, the footrest portion may be fixed to the sleeve via the cushioning material. Alternatively, the footrest portion is loosely fixed to the sleeve so as to be movable within a predetermined range (for example, slidable, swingable, and / or movable), and the movable range of such a footrest portion is narrowed. As described above, a cushioning material may be interposed between the footrest portion and the sleeve.

  In addition, when cushioning material is interposed between the footrest part and the subframe and between the footrest part and the sleeve, the footrest part is fixed to both the subframe and the sleeve via the cushioning material. Also good. Alternatively, the footrest portion is loosely fixed to the subframe and / or sleeve so as to be movable within a predetermined range (for example, slidable, swingable and / or movable), and such a footrest portion. A cushioning material may be interposed between the footrest portion and the subframe and between the footrest portion and the sleeve so as to narrow the movable range of the footrest.

  The cushioning material may be any member as long as it can reduce vibration and / or impact transmitted to the subframe and / or the sleeve footrest. Specific examples of such a buffer material include rubbers such as synthetic rubber (eg, silicone rubber, butadiene rubber (BR) and isoprene rubber (IR)) and natural rubber, thermoplastic resins and thermosetting resins. And the like, and gels such as silicone gel and urethane gel. Typically, the cushioning material is silicone rubber.

<Effect>
As described above, in the eighth wheelchair, the footrest portion is fixed to the sleeve so as to be movable within a predetermined range, and the cushioning material is interposed between the footrest portion and the subframe and / or the sleeve. doing. Therefore, according to the eighth wheelchair, vibration and impact transmitted from the road surface to the footrest portion via the front wheel caster during traveling can be reduced / damped. As a result, the vibration and impact transmitted from the road surface to the footrest part through the front wheel casters during driving can cause the occupant to feel uncomfortable, or the occupant's feet can move on the footrest. The possibility that a person's foot falls off the footrest can be reduced.

<< Ninth Embodiment >>
Hereinafter, a wheelchair according to a ninth embodiment of the present invention (hereinafter may be referred to as a “ninth wheelchair”) will be described.

  As described above, a specific coupling mode between the footrest portion and the subframe and / or the sleeve in the eighth wheelchair is fixed to the sleeve so that the footrest portion is movable within a predetermined range, and the footrest As long as the cushioning material is interposed between the portion and the subframe and / or the sleeve, there is no particular limitation.

  That is, the specific coupling mode between the footrest portion and the subframe and / or the sleeve is the shape of these members, the materials constituting these members, and the assembly method that can be adopted in the manufacturing process of the eighth wheelchair. Depending on the, various configurations can be employed. For example, by fixing one end of a footrest inserted into the sleeve, the footrest portion can be fixed to the sleeve so as to be movable within a predetermined range.

  However, from the viewpoint of reducing manufacturing costs, improving quality, and homogenizing, it is desirable to reliably achieve the above-described joining mode with a simpler structure and a smaller number of parts. In addition, it is desirable that the coupling mode between the footrest portion and the subframe and / or the sleeve has as little influence on the coupling mode and / or movable range of other related members as possible.

<Constitution>
Therefore, the ninth wheelchair is the above-described eighth wheelchair, in which the footrest portion and the sleeve are coupled by a ball joint, and a cushioning material is interposed between the footrest portion and the subframe. . Since the configuration of the ball joint is well known to those skilled in the art, the description thereof is omitted here.

  Further, the ball stud and the socket constituting the ball joint may be coupled to either side of the footrest portion and the sleeve. Specifically, the ball stud may be coupled to the footrest portion and the socket may be coupled to the sleeve. Alternatively, the ball stud may be coupled to the sleeve and the socket may be coupled to the footrest portion. Further, in the former case, the socket may constitute a sleeve.

<Effect>
As described above, in the ninth wheelchair, since the footrest portion and the sleeve are connected by the ball joint, the footrest portion rotates in any direction with respect to the sleeve while preventing the footrest portion from falling off the sleeve. Or any angle (rotational and swinging motions are possible). Furthermore, since the cushioning material is interposed between the footrest portion and the subframe, vibrations and impacts transmitted from the road surface to the footrest portion via the front wheel caster during traveling can be reduced / damped. As a result, the vibration and impact transmitted from the road surface to the footrest part through the front wheel casters during driving can cause the occupant to feel uncomfortable, or the occupant's feet can move on the footrest. The possibility that a person's foot falls off the footrest can be reduced more reliably.

  In addition, as described above, the footrest portion can rotate in an arbitrary direction with respect to the sleeve and can form an arbitrary angle. For example, the subframe is used for the purpose of adjusting the camber angle of the front wheel caster. Even when tuning the alignment of the sleeve with respect to, the influence on the positional relationship between the footrest portion and the subframe can be effectively reduced. In other words, by connecting the footrest portion and the sleeve by the ball joint, it is possible to greatly reduce the influence on the connection mode and / or movable range of other related members.

<< 10th Embodiment >>
Hereinafter, a wheelchair according to a tenth embodiment of the present invention (hereinafter may be referred to as a “tenth wheelchair”) will be described.

<Constitution>
The tenth wheelchair is any one of the seventh to ninth wheelchairs described above, wherein the footrest portion extends in the left-right direction and connects the left and right sleeves; And a pair of footrests that are members for placing a occupant's feet attached to the bar member.

<Effect>
The bar member functions as a structure that connects the left and right side frames via the sleeve and the sub-frame when not folded (when extended), increases the rigidity of the tenth wheelchair as a whole, and travels. Contributes to improved stability. On the other hand, at the time of folding, the bar member is bent, for example, in the vicinity of the center thereof, and does not hinder folding of the tenth wheelchair. The bent portion of such a bar member may be provided with a so-called “lock mechanism” so that the extended state can be reliably maintained when not folded (at the time of extension).

<< 11th Embodiment >>
The wheelchair according to the eleventh embodiment of the present invention (hereinafter may be referred to as “the eleventh wheelchair”) will be described below.

  As described above, the footrest part of the tenth wheelchair is a bendable bar member that extends in the left-right direction and connects the left and right sleeves, and a member for placing the foot of the occupant attached to the bar member. A set of footrests. The footrest can take various configurations depending on, for example, the physique of the occupant and the sitting posture.

<Constitution>
Therefore, the eleventh wheelchair is the tenth wheelchair described above, wherein the footrest is a plate-like member attached to the bar member, a curved pipe-like member attached to the bar member, and the bar member Any one member selected from the plate-like members attached to the curved pipe-like member attached to.

<Effect>
By adopting a plate-like member attached to the bar member in the eleventh wheelchair as a footrest, for example, the seat occupant has an obstacle such as inferiority of the lower body and can adjust the position of the foot by his own will. Even when it is difficult, it becomes easy to appropriately maintain the position and angle of the foot of the occupant. On the other hand, for example, for a seat occupant who can adjust the position of the foot according to his / her own will, by adopting a curved pipe-like member attached to the bar member as the footrest, for example, the structure of the footrest is It can be simplified, for example, reducing the need for regular maintenance or reducing the cost of wheelchairs. Further, in the eleventh wheelchair, the plate-like member as the footrest may be attached not only to the bar member but also to a curved pipe-like member attached to the bar member. Thereby, since the variation of the structure of a footrest can be increased, it becomes easy to maintain a leg | foot position, an angle, etc. more appropriately according to a passenger | crew's state.

<< Twelfth Embodiment >>
Hereinafter, a wheelchair according to a twelfth embodiment of the present invention (hereinafter may be referred to as a “twelfth wheelchair”) will be described.

  By the way, wheelchairs are used on a daily basis. For example, specifications such as color, shape, material, and structure are selected in accordance with the user's preference and the assumed use situation of the wheelchair. Against this background, wheelchairs having various structures are provided in the technical field, and a variety of options such as colors, shapes, and materials have been provided in each structure. .

  However, the environments and situations in which wheelchairs are used vary, and color schemes and / or designs suitable for sports and / or leisure, for example, are not necessarily suitable for celebrations such as funerals. Thus, it is difficult to suitably cope with all of various environments and situations by a single wheelchair having a specific specification. Nevertheless, owning a large number of wheelchairs with various specifications according to various environments and circumstances is expensive and impractical both in terms of economy and storage space.

  On the other hand, in this technical field, for example, for the purpose of protecting wheelchairs and occupants and improving aesthetics, for example, covers to be mounted on wheelchair components such as armrests and frames are commercially available. However, most of these existing covers are general-purpose products and do not fully meet the specifications of individual wheelchairs. Further, most of the covers for the purpose of protecting the wheelchair and the occupant do not consider aesthetics, for example, there is only a single color option such as black.

<Constitution>
Accordingly, the twelfth wheelchair is any one of the first to eleventh wheelchairs described above, and further includes an exterior cover that is a detachable member that covers at least a part of the surface of the side frame. In addition, in the twelfth wheelchair, at least a part of the portion of the side frame covered by the exterior cover occupies 50% or more of the surface of the side frame in a cross section orthogonal to the axial direction of the side frame. The exterior cover covers a continuous area.

  The portion of the side frame covered with the exterior cover can be appropriately selected according to the purpose of mounting the exterior cover. For the purpose of wheelchair protection, for example, a side that may come into contact with a occupant and / or other objects (eg, structures such as walls and pillars around the wheelchair) when using the wheelchair A portion of the frame can be covered with an exterior cover. Alternatively, for the purpose of protecting the occupant, a portion of the side frame that may come into contact with the occupant during use of the wheelchair, such as an armrest, for example, can be covered with the exterior cover. Alternatively, for the purpose of improving aesthetics, for example, a part of the side frame that is conspicuous in appearance such as a part having a large area and / or a part having a characteristic shape in the appearance of a wheelchair is covered with an exterior cover. Can do. Typically, the portion of the side frame covered by the exterior cover is a portion including at least a part of the surface of the curved portion.

  Of course, in the case where it is required for each purpose, at least a part of the surface of the constituent member other than the side frame of the wheelchair may be covered with a further exterior cover. Further, depending on the purpose, for example, decoration such as coloring, pattern, pattern, and unevenness is applied to the exterior cover, or a member made of a material different from that of the exterior cover is further arranged outside and / or inside the exterior cover. It may be installed. Specific examples of such a member include, for example, a cushioning material for improving the tactile sensation by a occupant and an anti-slip material for increasing the coefficient of friction between the inner surface of the outer cover and the outer surface of the side frame to suppress slippage. A liner etc. can be mentioned. Specific examples of such a non-slip liner include a rubber sheet such as silicone rubber and a double-sided tape.

  As described above, the exterior cover is detachably attached to at least a part of the surface of the side frame to cover the part. When attaching and detaching the exterior cover, it is desirable that the exterior cover can be easily attached and detached manually without using a special tool or the like. From such a viewpoint, it is desirable that the exterior cover is made of a flexible material.

  Specific examples of the material constituting the exterior cover include, for example, synthetic rubbers (for example, silicone rubber, butadiene rubber (BR) and isoprene rubber (IR)), rubbers such as natural rubber, thermoplastic resins, and thermosetting resins. Examples thereof include resins such as resins and gels such as silicone gel and urethane gel. Typical examples include silicone rubber, polyurethane, polycarbonate and the like.

  By configuring the exterior cover with the flexible material as described above, for example, when attaching or removing a silicone rubber cover to a mobile terminal such as a mobile phone or a smartphone, the surface of at least a part of the side frame The exterior cover can be easily attached and detached. Specifically, the outer cover is deformed elastically (reversibly) and fitted to a predetermined part of the side frame to attach or remove the outer cover from the part. It can be easily performed manually without using a tool or the like.

  In order to prevent an unintentional dropout of the exterior cover fitted to a predetermined part of the side frame as described above, it is desirable to wrap more than half of the outer surface of the side frame in the part with the exterior cover. . Accordingly, in the twelfth wheelchair, a continuous region that occupies 50% or more of the surface of the side frame in the cross section perpendicular to the axial direction of the side frame of at least a part of the portion covered by the exterior cover of the side frame is exteriorized. Cover is covered.

  For example, when the side frame is constituted by a so-called “round pipe” having a circular cross-sectional shape, a cross section perpendicular to the axial direction of at least a part of the side frame of the portion covered by the exterior cover of the side frame When the shape is circular, the central angle of the arc corresponding to the cross-sectional portion covered by the exterior cover is 180 ° or more.

  The ratio of the area of the side frame covered with the exterior cover of the above-mentioned cross section of the side frame (hereinafter sometimes simply referred to as “coverage”) of the side frame is the side frame. It is determined to achieve a good balance between the ease of attaching and detaching the exterior cover to the frame and the difficulty of falling off and / or displacing at the time of attachment. For example, when the coverage is excessively low, the outer cover can be easily attached to and detached from the side frame, while the outer cover may easily drop off or be displaced (displaced) during mounting. On the other hand, when the coverage is excessively high, it is difficult for the exterior cover to drop off or displace during mounting, and it may be difficult to attach or detach the exterior cover to the side frame. Further, the preferable coverage ratio also varies depending on, for example, the size and shape of the side frame and the structure and material of the exterior cover.

<Effect>
As described above, the twelfth wheelchair further includes an exterior cover that is a detachable member that covers at least a part of the surface of the side frame. This prevents, for example, damage to the wheelchair caused by contact with the occupant and / or other objects during use of the wheelchair, and provides an anti-slip effect to the part where the occupant grabs or puts weight. It is possible to suppress the “cool feeling” felt when the occupant touches during cold weather such as in winter, or to improve the aesthetics of the wheelchair. Furthermore, since the exterior cover is detachable, the appearance of the wheelchair can be easily and inexpensively changed according to the environment and situation in which the wheelchair is used by replacing the exterior cover.

  In addition, in the twelfth wheelchair, a continuous region occupying 50% or more of the surface of the side frame in a cross section perpendicular to the axial direction of the side frame of at least a part of the portion covered with the exterior cover of the side frame. The exterior cover is covering (that is, the coverage is 50% or more). This achieves a good balance between the ease of attaching / detaching the exterior cover to / from the side frame (easy attachability) and the difficulty of dropping and / or displacement during attachment (reliable attachment properties).

  Note that, as described above, in all the portions covered by the exterior cover of the side frame, it is not necessary that the coverage is 50% or more in the cross section orthogonal to the axial direction of the side frame. As described above, as long as a good balance between easy attachment / detachment and reliable attachment is achieved, there is a region where the coverage is less than 50% in the portion covered by the exterior cover of the side frame. Also good.

  By the way, as described above, the side frame can further include a back frame, which is a member for forming a backrest by a sheet-like member stretched between them, on the upper side of the upper frame. Further, the side frame includes a handle portion (also referred to as “assistance handle”) that is a member for an assistant to operate the wheelchair in addition to or instead of the backrest frame. it can. In addition, the wheelchair according to the present invention including the various embodiments including the first to twelfth embodiments described above (the wheelchair according to the present invention) is an essential member of the wheelchair according to the related art and / or as necessary. Alternatively, an optional member can be further provided. Specific examples of such a member include an armrest (armrest), a parking brake, and a fall prevention device (for example, a wheelie bar).

  As mentioned above, although the wheelchair which concerns on various embodiment of this invention has been demonstrated, it demonstrates in detail below, referring drawings for the typical Example of this invention.

  FIG. 1 is a schematic diagram showing the structure of a wheelchair according to a first embodiment of the present invention (hereinafter, sometimes referred to as “first embodiment wheelchair”) when extended (a) and when folded (b). FIG. 2 is a schematic front view (a), left side view (b), rear view (c), top view (d), and bottom view (e) of the wheelchair of the first embodiment shown in FIG. It is. In FIG. 2, the reference numerals of the constituent members are omitted. Further, in FIG. 1 and FIG. 2, the sheet-like member that forms the seat surface and the backrest, the spokes of the rear wheel, and the hand rim are omitted.

  As shown in FIGS. 1 and 2, the first embodiment wheelchair 100 is a wheelchair having a seat portion between a pair of side frames 120 </ b> R and 120 </ b> L connected by a pair of cross frames 110. Each of the pair of side frames 120R and 120L includes curved portions 121R and 121L that are formed in a part of each of the side frames 120R and 120L, and whose curvature can be changed by elastic deformation, upper frames 122R and 122L positioned above the curved portions 121R and 121L, and a curved shape. Lower frames 123R and 123L are provided below the portions 121R and 121L.

  As shown in detail in FIG. 3, the cross frame 110 includes a pair of arms 112 </ b> R and 112 </ b> L that are rotatably supported by a single pivot 111. As can be understood from FIGS. 1 and 3, the upper frames 122R and 122L of the pair of side frames 120R and 120L are respectively connected via connecting members 113R and 113L rotatably supported by the upper frames 122R and 122L. The upper arms 112Ru and 112Lu, which are portions above the pivots 111 of the arms 112R and 112L of the cross frame 110, are rotatably supported.

  As can be understood from FIGS. 1 and 3, the lower frames 123R and 123L of the pair of side frames 120R and 120L are portions below the pivots 111 of the arms 112R and 112L of the cross frame 110, respectively. The lower ends of the lower arms 112Rd and 112Ld are rotatably supported. Further, front wheel casters 130R and 130L and main shafts 141R and 141L of rear wheels 140R and 140L are mounted on the lower frames 123R and 123L, respectively. That is, the vibration and impact transmitted from the road surface through the front wheel casters 130R and 130L and the rear wheels 140R and 140L during traveling are transmitted to the lower frames 123R and 123L of the pair of side frames 120R and 120L.

  Incidentally, FIG. 4 shows a schematic cross-sectional view (AA cross-sectional view) along the line AA shown in the bottom view (e) of FIG. FIG. 4 shows the right side frame 120R of the pair of side frames 120R and 120L. For the purpose of helping understanding of the drawing, the rear wheel 140R is also drawn in FIG. As shown in FIG. 4, the side frame 120R is formed of an integral hollow pipe, and has a U-shaped shape in which the continuous upper frame 122R, curved portion 121R, and lower frame 123R open rearward. Yes.

  With the above-described configuration, the wheelchair 100 according to the first embodiment has the curved portions 121R provided in the middle of the side frames 120R and 120L for vibration and impact transmitted from the road surface via the front wheel casters 130R and 130L and the rear wheels 140R and 140L when traveling. And 121L can be relaxed and attenuated by elastic deformation. As a result, according to the wheelchair 100 of the first embodiment, vibrations and shocks transmitted from the road surface during traveling can be reliably mitigated and attenuated without adding a vibration / impact absorbing structure such as a suspension.

  Further, in the wheelchair 100 according to the first embodiment, the pair of side frames 120R and 120L are connected to each other by the cross frame 110 and the connecting members 113R and 113L. As a result, according to the wheelchair 100 of the first embodiment, an unintentional change occurs in the mutual alignment of the four wheels (the front wheel casters 130R and 130L and the rear wheels 140R and 140L), and the occupant feels a lot of discomfort. It is possible to reduce the possibility that it is difficult to advance the first embodiment wheelchair 100 in the desired direction or the first embodiment wheelchair 100 travels in an unintended direction.

  As shown in FIG. 4, a subframe 124R, which is a member extending forward, is fixed to the lower frame 123R of the side frame 120R, and a sleeve is slidable in the front-rear direction on the subframe 124R. 125R is fixed, and the base portion of the front wheel caster 130R is fixed to the sleeve 125R. Further, a footrest portion 126 is fixed to the sleeve 125R. In addition, as shown by the part enclosed with the broken line in FIG.1 and FIG.7, the footrest part 126 is not only a footrest which is a member for putting a passenger | crew's leg | foot, but also a footrest is a side frame and / or sub-frame. It also includes a member for attaching to the head.

  More specifically, by screwing two bolts inserted in through holes formed in the tube wall of the sub-frame 124R in the front-rear direction into screw holes (nut holes) formed in the sleeve 125R, A sleeve 125R is fixed to the subframe 124R. In addition, by loosening the bolt and moving the inside of the through hole in the front-rear direction, the sleeve 125R fitted in the sub-frame 124R is slid in the front-rear direction, and the positions of the front wheel casters 130R and the footrest part 126 are changed. Can be adjusted.

  FIG. 5 is a schematic diagram showing a state in which the front wheel casters 130R and the footrest portions 126 are arranged at positions closest to the occupant in the wheelchair 100 of the first embodiment. (A) is a bottom view, (b) is a sectional view taken along line AA shown in (a), and (c) to the front wheel caster 130R and the sub-frame 124R of the footrest part 126 in (b) above. It is an enlarged view of the fixed part.

  In the example shown in FIG. 5, two bolts 125Rb are inserted into the rearmost side of a through hole 124Ra formed in the tube wall of the subframe 124R and extending in the front-rear direction. In this state, the two bolts 125Rb are screwed into screw holes (nut holes) formed in the sleeve 125R, so that the sleeve 125R is fixed to the rearmost side with respect to the subframe 124R. That is, in the wheelchair 100 of the first embodiment, the front wheel casters 130R and the footrest portion 126 are disposed at positions closest to the occupant.

  On the other hand, FIG. 6 is a schematic diagram showing a state in which the front wheel casters 130R and the footrest portions 126 are arranged at positions farthest from the occupant in the wheelchair 100 of the first embodiment. (A) is a bottom view, (b) is a sectional view taken along line BB shown in (a), and (c) to the front wheel caster 130R and the sub-frame 124R of the footrest portion 126 in (b) above. It is an enlarged view of the fixed part.

  In the example shown in FIG. 6, two bolts 125Rb are inserted in the foremost side of a through hole 124Ra formed in the tube wall of the subframe 124R and extending in the front-rear direction. In this state, the two bolts 125Rb are screwed into screw holes (nut holes) formed in the sleeve 125R, so that the sleeve 125R is fixed to the foremost side with respect to the subframe 124R. That is, in the wheelchair 100 according to the first embodiment, the front wheel casters 130R and the footrest portion 126 are disposed at positions farthest from the occupant. Although not shown, the same applies to the left side frame 120L.

  As described above, according to the wheelchair 100 of the first embodiment, the footrest portion 126 and the front wheel casters 130R and 130L are integrally moved by sliding the sleeves 125R and 125L with respect to the sub frames 124R and 124L. be able to. As a result, unlike the conventional wheelchair, the distance between the footrest and the front wheel caster becomes narrow, and the possibility of contact / interference between the foot of the occupant and the front wheel can be reduced.

  Furthermore, in the wheelchair 100 of the first embodiment, the sleeves 125R and 125L are slid in the front-rear direction (not in the vertical direction) with respect to the subframes 124R and 124L, whereby the footrest portion 126 and the front wheel casters 130R and 130L are connected. It can be moved back and forth. Therefore, it is possible to reduce the possibility that it is difficult to secure the minimum ground clearance of the footrest as in the case of a conventional wheelchair or that the foot of the occupant comes into contact with the road surface (ground).

  However, as described above, it may be configured such that the attachment positions of the base portions of the front wheel casters 130R and 130L and the footrest portion 126 with respect to the sleeves 125R and 125L can be independently adjusted. Further, in this case, a limit may be provided to the adjustable range of each position to reduce the possibility of contact / interference between the occupant's feet and the front wheels as described above.

  In addition, in the wheelchair 100 according to the first embodiment, an external load (for example, the weight of the occupant) acts on the seat portion of the wheelchair 100 according to the first embodiment when in use (that is, when extended). In a state (free state) in which the left and right rear wheels 140R and 140L are in a radial direction with respect to a plane (pivot plane) including the axial direction of the pivot 111 of the cross frame 110 and a horizontal direction orthogonal to the axial direction And the center in both directions of the width direction (rear wheel center. The center in the width direction of the main shafts 141R and 141L) is arranged so as to be on the lower side in the vertical direction.

  When the occupant sits on the seat of the wheelchair 100 according to the first embodiment as described above, the seat sinks due to the weight of the occupant, the cross frame 110 opens, and the pivot plane becomes the rear wheel. Get closer to the center. Ideally, as shown in FIG. 7, when the occupant sits on the seat, the pivot 111 of the cross frame 110 and the main shafts 141R and 141L of the left and right rear wheels have the same ground height. At this time, the direction of the tangent in the main shafts 141R and 141L of the left and right rear wheels of the circle centering on the pivot 111 and passing through the main shafts 141R and 141L of the left and right rear wheels is the vertical direction (vertical direction). Therefore, according to the wheelchair 100 of the first embodiment, only relative movement in the vertical direction is allowed between the upper frames 122R and 122L and the lower frames 123R and 123L, and movements such as three-axis bending and / or twisting are prevented. Is done. In other words, according to the wheelchair 100 of the first embodiment, the above-described “positioning effect by the cross frame” can be sufficiently exhibited.

  Next, FIG. 8 shows a schematic (a) front view, (b) top view, and (c) left side view of the cross frame 110 of the wheelchair 100 of the first embodiment during extension (for example, during travel). As shown in FIG. 8, in the wheelchair 100 of the first embodiment, seat frames 114R and 114L, which are non-linear members, are fixed to the upper ends of the pair of upper arms 112R and 112L of the cross frame 110, respectively. . Although omitted in FIG. 8, the seat surface of the seat is formed as a curved surface that is not a simple plane by stretching a sheet-like member (for example, cloth) between the two seat frames 114R and 114L. can do.

  Specifically, in the wheelchair 100 according to the first embodiment, the distance between the left and right seat frames 114R and 114L is in the region where the occupant's buttocks ride (the region surrounded by the broken line in FIG. 8B). The seat frames 114R and 114L are curved so as to be wide. On the other hand, the seat frames 114R and 114L are curved so that the height of the left and right seat frames 114R and 114L is higher in the region close to the knee of the occupant (the region surrounded by the dotted line in FIG. 8B). doing. Thereby, a hip and a waist | hip | lumbar part when a seated person sat down are appropriately hold | maintained three-dimensionally, and a seated person's attitude | position can be stabilized. As a result, it is possible to reduce the possibility of a secondary failure resulting from the inability of the seated occupant to hold an appropriate sitting position.

  By the way, as described at the beginning of this embodiment, the wheelchair 100 according to the first embodiment is a foldable wheelchair. Specifically, the wheelchair 100 of the first embodiment rotates the pair of arms 112R and 112L around the pivot 111 so that the longitudinal direction of the pair of arms 112R and 112L constituting the cross frame 110 is brought close to the vertical direction. Thus, the space between the pair of side frames 120R and 120L can be reduced, and the volume occupied by the wheelchair 100 in the first embodiment can be reduced.

  However, as explained with reference to FIG. 8, the wheelchair 100 of the first embodiment employs non-linear seat frames 114R and 114L. In such a case, in a state where the wheelchair is folded, the left and right seat frame may interfere with each other, and it may be difficult to fold the wheelchair sufficiently small.

  However, in the wheelchair 100 of the first embodiment, the axes of the seat frames 114R and 114L are two-dimensionally curved in one plane. As shown in FIG. 9, in the folded state of the wheelchair 100 according to the first embodiment, the pair of cross frames 110 are arranged so that the two planes including the axes of the two seat frames 114R and 114L are parallel to each other. The seat frames 114R and 114L are fixed to the upper ends of the upper arms 112R and 112L, respectively.

  Therefore, according to the wheelchair 100 of the first embodiment, the seat surface that can sufficiently hold the seated position of the occupant when unfolded (extension) and the left and right seat frame 114R and 114L are mutually connected when folded. A seat frame that does not interfere can be made compatible. In other words, the wheelchair 100 according to the first embodiment can sufficiently hold the seated position of the occupant during extension, and can be folded compactly when folded.

  As shown in FIG. 5A, in the wheelchair 100 according to the first embodiment, the footrest portion 126 extends in the left-right direction and bends a bar member 127 that connects the left and right sleeves 125R and 125L. And a pair of footrests 128 </ b> R and 128 </ b> L, which are members for placing the occupant's feet attached to the bar member 127.

  However, the footrests 128R and 128L are not limited to the curved pipe-shaped member as shown in FIG. 5A, and for example, a plate attached to a bar member (not shown) as shown in FIG. It may be a plate-like member or a plate-like member attached to a curved pipe-like member attached to a bar member. Regardless of the shape of the footrests 128R and 128L, according to the wheelchair 100 of the first embodiment, the positions of the footrests 128R and 128L can be easily adjusted in the front-rear direction as shown by the white arrows in FIG. Can do.

  At the beginning of the present specification, reference has been made to an assisting wheelchair pushed by an assistant or the like, and a self-propelled wheelchair that a passenger rides by himself (drives the rear wheel), but the wheelchair to which the present invention is applied. The form of is not limited to these. Specifically, the present invention can be applied to an electric wheelchair. For example, a beam is passed between the left and right lower frames 123R and 123L, a battery and a motor are supported by the beam, and a drive shaft that transmits driving force from the motor to the axles of the left and right rear wheels 140R and 140L is connected. It can also be configured to.

  Also, for example, equipped with sensors for detecting information on the body of the occupant (for example, pulse and body temperature) and / or GPS (Global Positioning System) for detecting position information of the occupant (wheelchair), etc. It is also possible to transmit information detected by them to a predetermined transmission destination (for example, a data collection center) by a communication means (transmission / reception system) so that the health condition and position of the sitting passenger can be remotely monitored in real time. it can.

  Next, a wheelchair according to a second embodiment of the present invention (hereinafter, may be referred to as “second embodiment wheelchair”) will be described in detail below with reference to the drawings.

  FIG. 11 is a schematic top view (a) and right side view (b) of the wheelchair of the second embodiment. The wheelchair 200 according to the second embodiment is further provided with handle portions 191R and 191L (assisting handles), armrests 192R and 192L (armrest), parking brakes 193R and 193L, and fall prevention devices 194R and 194L (willy bar), Basically, it has the same configuration as the wheelchair 100 of the first embodiment described above. Therefore, in FIG. 11, the same reference numerals as those of the first embodiment wheelchair 100 are attached to the same components as those in the first embodiment wheelchair 100, and in the following description, explanations regarding these common components are omitted. In FIG. 11, the sheet-like member that forms the seating surface and the backrest, the front wheel casters 130R and 130L, and the rear wheels 140R and 140L are omitted.

  However, the second embodiment wheelchair 200 is a wheelchair corresponding to the ninth wheelchair described above. That is, the footrest portion 126 is fixed to the sleeves 125R and 125L so as to be movable within a predetermined range, and the cushioning material is interposed between the footrest portion 126 and the sub frames 124R and 124L and / or the sleeves 125R and 125L. Is intervening. More specifically, as shown in a region surrounded by a broken line in FIG. 12A, the footrest portion 126 and the sleeve 125R are coupled by a ball joint 150R.

  FIG. 12B is an enlarged view of a region surrounded by a broken line in FIG. The ball joint 150R includes a ball stud 151R and a socket 152R. The socket 152R is divided into an upper socket member 152Ru and a lower socket member 152Rd, whereby the spherical portion of the ball stud 151R can be accommodated in the socket 152R. In this example, the ball stud 151R is coupled to the footrest portion 126, and the socket 152R is coupled to the sleeve 125R. Further, a cushioning material 153R is interposed between the footrest portion 126 and the subframe 124R. Although not shown, the connection between the footrest portion 126 and the left sleeve 125L is the same as described above. Further, as described above, the sockets 152R and 152L may constitute the sleeves 125R and 125L, respectively.

  As described above, in the wheelchair 200 according to the second embodiment, the footrest portion 126 and the sleeves 125R and 125L are coupled by the ball joints 150R and 150L, respectively. Accordingly, the footrest portion 126 can be rotated in an arbitrary direction or at an arbitrary angle with respect to the sleeves 125R and 125L while preventing the footrest portion 126 from falling off the sleeves 125R and 125L. (Rotating and swinging motions are possible) Further, cushioning materials 153R and 153L are interposed between the footrest portion 126 and the subframes 124R and 124L, respectively.

  With the configuration described above, vibration and impact transmitted from the road surface to the footrest portion 126 via the front wheel casters during traveling can be reduced / damped. As a result, the vibration and impact transmitted from the road surface to the footrest 126 through the front wheel caster during traveling may cause the occupant to feel uncomfortable, the occupant's feet may move on the footrest, and in some cases The possibility that the passenger's foot falls off the footrest can be reduced more reliably.

  In addition, as described above, the footrest portion 126 can rotate in an arbitrary direction with respect to the sleeves 125R and 125L, or can form an arbitrary angle. For example, the camber angle of the front wheel caster can be adjusted. Even when tuning the sleeve alignment with respect to the subframe as an object, the influence on the positional relationship between the footrest portion 126 and the subframes 124R and 124L can be effectively reduced. In other words, by connecting the footrest portion 126 and the sleeve sleeves 125R and 125L by the ball joints 150R and 150L, respectively, the influence on the connection mode and / or the movable range of other related members can be greatly reduced. Can do.

  Here, the reduction effect in the wheelchair 200 of the second embodiment of the vibration and impact transmitted from the road surface to the footrest portion 126 via the front wheel casters during traveling will be described in detail below. FIG. 13 is a schematic diagram showing a state where the front wheel casters and the rear wheels (main wheels) of the wheelchair descend on the step after being artificially provided. In FIG. 13, the smaller circle schematically represents the front wheel caster, the larger circle represents the rear wheel, and the bent line segment schematically represents the wheelchair frame. A straight line extending to the left and right represents the road surface, and a horizontally long rectangle drawn on the straight line represents a step on the road surface.

  Here, when the wheelchair 200 of the second embodiment travels on the road surface having the above steps, vibrations and impacts transmitted to the footrest portion and the front wheel casters are detected by an acceleration sensor mounted on the axles of the footrest and front wheel casters. Measured. Moreover, the same measurement was performed also about the wheelchair which concerns on a prior art (conventional wheelchair) as a comparison control. In the conventional wheelchair, the footrest portion is rigidly fixed to the sleeve, and no cushioning material is interposed between the footrest portion, the subframe, and the sleeve. In other words, the conventional wheelchair does not include a mechanism for reducing and attenuating vibration and impact transmitted from the front wheel caster to the footrest portion as provided in the wheelchair 200 of the second embodiment.

  Each wheelchair was run as follows by the same occupant rowing (driving) himself. First, as shown in the start column of FIG. 13, the wheelchair is started to run from the front of the step (left side as viewed in the figure). Eventually, the front wheel casters reach the step and ride on the step. This time is referred to as “time A”. After that, the rear wheel also reaches the step and rides on the step. This time is referred to as “time B”. Then, the front wheel caster reaches the end of the step and descends from the step. This time is referred to as “time C”. Finally, the rear wheel also reaches the end of the step and descends from the step. This time is referred to as “time D”.

  FIGS. 14 and 15 show changes with time of acceleration measured by the acceleration sensor mounted on the axles of the footrest and the front wheel caster in the running test. FIG. 14 shows the result of a running test for a conventional wheelchair, and FIG. 15 shows the result of a running test for a wheelchair 200 according to the second embodiment. In any graph, the ranges of acceleration and time indicated by the vertical axis and the horizontal axis are the same, and the four times A to D described above are indicated by symbols and arrows.

  As shown in FIG. 14, with regard to the conventional wheelchair, a large acceleration in the front and rear direction of the footrest was measured at time A, which is the time when the front wheel caster climbs the step, and then a large acceleration was measured in the front and rear direction and the vertical direction. . Thereafter, at time B, when the rear wheel climbs up the step, no large acceleration was measured for either the footrest or the axle of the front wheel caster. Then, at time C, when the front wheel caster reaches the end of the step and descends from the step, a large acceleration in the front-rear direction and the vertical direction of the footrest was measured again. Finally, at time D, when the rear wheel reaches the end of the step and descends from the step, no large acceleration was measured for either the footrest or the axle of the front wheel caster.

  From the above results, in a conventional wheelchair that does not have a mechanism for reducing and attenuating vibration and shock transmitted from the front wheel caster to the footrest part, vibration and shock are transmitted from the road surface to the footrest part through the front wheel caster during traveling. It was confirmed. As a result, in a conventional wheelchair, for example, the occupant may feel uncomfortable, the occupant's feet may move on the footrest, or the occupant's feet may fall off the footrest in some cases. is there.

  On the other hand, as shown in FIG. 15, in the wheelchair 200 of the second example, the measured acceleration was generally small in both the footrest and the axle of the front wheel caster as compared with the conventional wheelchair. In particular, the acceleration measured at the time A when the front wheel caster rides on the step and the time C when the front wheel caster reaches the end of the step and descends from the step is significantly reduced as compared with the conventional wheelchair. It was done.

  From the above results, the footrest portion 126 and the sleeves 125R and 125L are coupled by the ball joints 150R and 150L, respectively, and the cushioning materials 153R and 153L are interposed between the footrest portion 126 and the subframes 124R and 124L, respectively. In the wheelchair 200 according to the second embodiment, it was confirmed that vibration and impact transmitted from the road surface to the footrest portion 126 via the front wheel casters 130R and 130L during traveling can be effectively reduced. As a result, according to the wheelchair 200 of the second embodiment, for example, the occupant feels uncomfortable, the occupant's foot moves on the footrest, or the occupant's foot may fall off the footrest in some cases. It is possible to more surely reduce the possibility of dripping.

  By the way, as described at the beginning of the present embodiment, the wheelchair 200 according to the second embodiment has the handle portions 191R and 191L (assisting handle), the armrests 192R and 192L (armrest), the parking brakes 193R and 193L, and the fall prevention device 194R. And 194L (willie bar). Here, a seat surface formed by a sheet-like member stretched between the seat frames 114R and 114L, which is omitted in FIG. 11, and a sheet-like member stretched between the side frames 120R and 120L. The external appearance of the wheelchair 200 of the second embodiment including the backrest, the front wheel casters 130R and 130L, and the rear wheels 140R and 140L is shown as a perspective view in FIG.

  As shown as a specific example in FIG. 16, the wheelchair according to the present invention (the wheelchair according to the present invention) including the wheelchair 100 according to the first embodiment and the wheelchair 200 according to the second embodiment, An essential member and / or an optional member can be further provided.

  Next, a wheelchair according to a third embodiment of the present invention (hereinafter may be referred to as a “third embodiment wheelchair”) will be described in detail below with reference to the drawings. FIG. 17 is a schematic perspective view showing the external appearance of a third embodiment wheelchair 300 provided with exterior covers 160R and 160L. Further, FIG. 18 is a schematic perspective view in which constituent members other than the exterior covers 160R and 160L of the wheelchair 300 of the third embodiment are drawn by dotted lines for the purpose of making the appearance of the exterior covers 160R and 160L easy to understand. In addition, FIG. 19 is a six-sided view (a front view (a), a rear view (b), and a plan view (top view) showing the structure of an exterior cover 160R attached to the right side frame 120R of the wheelchair 300 of the third embodiment. (C), low view (bottom view) (d), left side view (e) and right side view (f)) and isometric views (isometric views) (g) and (h).

  As shown in FIG. 17, the third embodiment wheelchair 300 is a wheelchair according to the present invention (the present invention wheelchair) including various embodiments including the first embodiment wheelchair 100 and the second embodiment wheelchair 200 described above. In addition, exterior covers 160R and 160L, which are detachable members that respectively cover at least some of the surfaces of the side frames 120R and 120L, are further provided. The other members constituting the wheelchair of the present invention have been described in detail in the description of the above-described various embodiments and various examples, and thus the reference numerals in the description and the drawings are omitted here.

  More specifically, the exterior covers 160R and 160L cover the surfaces of the side frames 120R and 120L including at least a part of the surfaces of the curved portions 121R and 121L. Since this portion has a large area in the appearance of the wheelchair of the present invention and has a characteristic shape, it has a great influence on the appearance of the wheelchair of the present invention. For example, in FIG. 17A, the exterior covers 160R and 160L are colored in a dark color, and in FIG. 17B, the exterior covers 160R and 160L are colored in a light color. As is clear from these comparisons, the appearance of the wheelchair of the present invention can be changed by covering the portions of the side frames 120R and 120L that are conspicuous in appearance with the exterior covers 160R and 160L.

  In addition, according to the wheelchair 300 of the third embodiment, not only the appearance aesthetics of the wheelchair is improved as described above, but also, for example, due to contact with a seated person and / or other objects when using the wheelchair. To prevent the wheelchair from being damaged, to provide a non-slip effect to the part that the occupant grabs and puts on the weight, and to feel the "cold feeling" that the occupant feels when touching during cold weather such as in winter It can be suppressed. Further, by forming the exterior covers 160R and 160L with a member having a light reflecting function, or coloring the exterior covers 160R and 160L with a paint having a light reflecting function, the visibility of the wheelchair 300 according to the third embodiment. Can be improved. In addition, since the exterior covers 160R and 160L are detachable, the exterior of the third embodiment wheelchair 300 can be changed according to the environment and situation in which the third embodiment wheelchair 300 is used by replacing the exterior covers 160R and 160L. It can be changed easily and inexpensively.

  In the wheelchair 300 according to the third embodiment, the side frames 120R and 120L and The exterior covers 160R and 160L cover a continuous region that occupies 50% or more of the surface of 120L (that is, the coverage is 50% or more).

  As described above, a good balance between the ease of attaching and detaching the exterior covers 160R and 160L to the side frames 120R and 120L (easy detachability) and the difficulty of dropping and / or displacement at the time of attachment (reliable attachment properties). Is achieved. In other words, the exterior covers 160R and 160L can be easily attached to and detached from the side frames 120R and 120L, and the exterior covers 160R and 160L can be prevented from dropping or shifting from the side frames 120R and 120L at the time of attachment. .

  The exterior covers 160R and 160L provided in the wheelchair 300 of the third embodiment are formed of silicone rubber that is a material having moderate flexibility. However, as described above, the exterior cover is made of various materials such as rubbers such as synthetic rubber and natural rubber, resins such as thermoplastic resins and thermosetting resins, and gels such as silicone gel and urethane gel. A suitable material can be selected from these according to the mounting purpose of the exterior cover. In addition, according to the material of the exterior cover and the structure of the exterior cover selected in this way, the size and shape of the side frame, etc. The “coverage” can be determined as appropriate.

  In the above, for the purpose of explaining the present invention, several embodiments and modifications having specific configurations have been described with reference to the accompanying drawings. However, the scope of the present invention is not limited to these illustrative examples. It should be understood that the present invention should not be construed as being limited to the embodiments and the modifications, and that appropriate modifications can be made within the scope of the matters described in the claims and the specification.

  DESCRIPTION OF SYMBOLS 100, 200 and 300 ... Wheelchair, 110 ... Cross frame, 111 ... Pivot, 112R and 112L ... Arm, 112Ru and 112Lu ... Upper arm, 112Rd and 112Ld ... Lower arm, 113R and 113L ... Connecting member, 114R and 114L ... Seat Frames, 120R and 120L ... side frames, curved parts ... 121R and 121L, 122R and 122L ... upper frames, 123R and 123L ... lower frames, 124R and 124L ... subframes, 124Ra and 124La ... through holes, 125R and 125L ... sleeves, 125Rb and 125Lb ... bolts, 126 ... footrest part, 127 ... bar member, 128R and 128L ... footrest, 130R and 130L ... front wheel casters, 140R and 140L ... rear wheel 141R and 141L ... main shaft of rear wheel, 150R and 150L ... ball joint, 151R and 151L ... ball stud, 152R and 152L ... socket, 152Ru and 152Lu ... upper socket member, 152Rd and 152Ld ... lower socket member, 153R and 153L ... Buffer material, 160R and 160L ... exterior cover, 191R and 191L ... handle part (assistant handle), 192R and 192L ... armrest (armrest), 193R and 193L ... parking brake, and 194R and 194L ... fall prevention device (willy bar) .

Claims (12)

A wheelchair having a seat portion between a pair of side frames connected by at least one pair of cross frames,
Each of the pair of side frames includes a curved portion that is formed at a part of the pair of side frames and can change a curvature by elastic deformation, an upper frame that is located above the curved portion, and a lower portion that is located below the curved portion. With a frame,
The cross frame is composed of a pair of arms that are pivotally supported by one pivot so as to be mutually rotatable.
The upper frame of each of the pair of side frames rotates an upper arm that is a part above the pivot of the arm of the cross frame via a connecting member rotatably supported by the upper frame. Is pivotally supported,
The lower frame of each of the pair of side frames rotatably supports a lower end of a lower arm, which is a lower part of the pivot of the arm of the cross frame, and a front wheel caster and a main shaft of a rear wheel Is installed,
In each of the pair of side frames, the upper frame and the lower frame are not adjacent to each other, and the curved portion is formed between the upper frame and the lower frame,
The two arms constituting the cross frame are configured to rotate around the axis of the pivot as the upper frame and the lower frame move relative to each other in the vertical direction.
wheelchair. The wheelchair according to claim 1,
Each of the pair of side frames is formed of an integral hollow pipe, and forms a U-shape in which the continuous upper frame, the curved portion, and the lower frame are opened rearward.
wheelchair. The wheelchair according to claim 1 or claim 2,
In a free state in which no external load is applied to the seat portion of the wheelchair in use, the plane includes a pivot axis of the cross frame and a horizontal straight line perpendicular to the axis. On the other hand, the left and right rear wheels are arranged such that the centers in both the radial direction and the width direction are on the lower side in the vertical direction.
wheelchair. A wheelchair according to any one of claims 1 to 3,
A seat frame that is a non-linear member is fixed to the upper ends of the pair of upper arms of the cross frame,
The seat surface of the seat is formed by a sheet-like member stretched between the two seat frames.
wheelchair. A wheelchair according to claim 4,
The wheelchair reduces the interval between the pair of side frames by rotating the pair of arms around the pivot so that the longitudinal direction of the pair of arms constituting the cross frame approaches the vertical direction. , A foldable wheelchair that can reduce the volume occupied by the wheelchair,
The axis of the seat frame is curved two-dimensionally in one plane,
The seat frame is fixed to the upper ends of the pair of upper arms of the cross frame so that two planes including the shafts of the two seat frames are parallel to each other in the folded state of the wheelchair. ing,
wheelchair. A wheelchair according to any one of claims 1 to 5,
A subframe that is a member extending forward is fixed to the lower frame of the side frame,
A sleeve is fixed to the subframe so as to be slidable in the front-rear direction,
A base of the front wheel caster is fixed to the sleeve;
wheelchair. The wheelchair according to claim 6,
A footrest portion is fixed to the sleeve,
wheelchair. A wheelchair according to claim 7,
The footrest portion is fixed to the sleeve so as to be movable within a predetermined range,
A cushioning material is interposed between the footrest part and the subframe and / or the sleeve,
wheelchair. A wheelchair according to claim 8,
The footrest part and the sleeve are joined by a ball joint,
A cushioning material is interposed between the footrest portion and the subframe,
wheelchair. A wheelchair according to any one of claims 7 to 9,
The footrest portion is a bendable bar member that extends in the left-right direction and connects the left and right sleeves, and a pair of footrests that are members for placing a foot of a occupant attached to the bar member; ,including,
wheelchair. A wheelchair according to claim 10,
The footrest is a plate-like member attached to the bar member, a curved pipe-like member attached to the bar member, and a plate-like member attached to the curved pipe-like member attached to the bar member Any one member selected from the members of
wheelchair. A wheelchair according to any one of claims 1 to 11,
An exterior cover that is a detachable member that covers at least a part of the surface of the side frame;
The exterior cover covers a continuous region occupying 50% or more of the surface of the side frame in a cross section perpendicular to the axial direction of the side frame of at least a part of the portion of the side frame covered by the exterior cover. doing,
wheelchair.

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