JPH0226493Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> This invention relates to a foldable wheelchair, and particularly to a wheelchair configured such that left and right support frames are parallel to each other and are spaced apart from each other.

<Prior art> Conventionally, in a foldable wheelchair, the left and right support frames are connected to a pair of support rods, which intersect diagonally at the center, and are rotatably connected at the intersection. , the supporting frames were constructed so that they were close to each other and separated from each other. A wheelchair configured like this is
When folded, the space between the left and right support frames tends to widen above the intersection of the support frames due to the bulk of the sheet and other members. As a result, there are problems in that it takes up storage space when stored, and the space between the support frames tapers downward, making it unstable to place.

In order to solve this problem, a pair of horizontal rods rotatably connected to each other is provided between the left and right support frames, and this pair of horizontal rods and the lower legs of the left and right support frames are supported diagonally. A pair of horizontal rods connected with each other by a rod, or a pair of horizontal rods rotatably connected to each other between the left and right support frames, is provided at a predetermined interval in the vertical direction, and this upper and lower horizontal rod assembly is used. are connected diagonally with support rods, and the left and right support frames are moved in parallel when they are brought close to each other or separated, and even when both support frames are brought close together, the parallel state is maintained so that it can be folded compactly. A wheelchair has been proposed (for examples of such a wheelchair, see the embodiment shown in Japanese Utility Model Publication No. 52-52364 and the conventional example).

<Problems to be solved by the invention> However, in wheelchairs with conventional configurations such as the former configuration, only a pair of horizontal rods connect the left and right support frames. However, there was a problem that the lateral strength of the wheelchair was weak.

In addition, in the case of the latter configuration, the support at the center of the upper and lower horizontal rods is two diagonally crossed horizontal rods.
Since the wheelchair only has a book support rod, its strength in the vertical direction is weak.Furthermore, there are many pivot points for each member, so it takes time and effort to assemble the wheelchair.

<Means for solving the problem> This invention was made to solve the above problem, and is a foldable wheelchair with upper and lower legs arranged at a predetermined distance from each other. , Nakasan,
A pair of support frames each having a lower deck, a sheet stretched between the two upper decks, one end of which is pivotally attached to the middle deck, and the inner free ends of which are rotatably connected to each other by a connecting rod. A pair of upper parallel links are each formed to have the same length as the pair of upper parallel links, one end of which is pivotally attached to the lower leg, and the inner free ends of which are rotatably connected to each other by a pivot pin. The pair of lower parallel links and both ends thereof are pivotally connected to the connecting portion of the pair of upper parallel links and the connecting portion of the pair of lower parallel links, respectively, and the distance between the axes of the two connecting portions is an intermediate piece having a length equal to the distance between the axes of the pivoting part of the upper parallel link to the upper leg and the pivoting part of the lower parallel link to the lower leg; a pair of support rods each having a long length, one end of which is pivotally connected to the lower rung together with the lower parallel link, and free ends of which extend upwardly inside the support rods and which are rotatably connected to each other by a support shaft; The supporting shaft is fixed and a sliding member is guided by the intermediate piece so as to be movable in the vertical direction, so that when the pair of upper parallel links are in a straight line, the connecting portion thereof comes into contact with the sliding member. It is a wheelchair made of

<Function> This device is constructed as described above, and consists of a support frame on one side (between the middle and lower supports), and an upper parallel frame on one side that is pivoted to the center support of the support frame. The link, the lower parallel link on one side pivoted to the lower leg of the support frame, and the intermediate piece form a parallelogram on one side.

A support frame on the other side (between its middle and lower legs), and an upper parallel link on the other side that is pivotally connected to the middle frame of the support frame,
The lower parallel link on the other side pivotally attached to the lower leg of the support frame and the intermediate piece form a parallelogram on the other side.

These two parallelograms form a symmetrical parallel link mechanism with the middle piece as the plane of symmetry, and when the left and right support frames are moved close to each other or separated, the left and right support frames are close to each other in a parallel state. Separation takes place.

On the other hand, when the left and right support frames are separated the most, the pair of upper parallel links and the pair of lower parallel links are straight and parallel, and the sliding member moves along the free end of the support rod. At the same time, it is guided by the intermediate piece and reaches the upper part of the intermediate piece.

At this time, the free ends of the pair of upper parallel links are
Each pair of upper and lower parallel links that come into contact with the sliding member are connected and supported at their central portions by an intermediate piece and a pair of diagonal supporting frames to maintain their linear state.

<Example> An example of this invention will be described below with reference to Figures 1 to 4.
This will be explained based on the diagram.

In the figure, the supporting frames 1 and 5 are formed in the same shape, and the upper supports 2 and 6 are provided on the upper parts of the supporting frames 1 and 5, respectively, and the middle supports 3 and 6 are provided below the upper supports 2 and 6, respectively. 7
are provided below the middle rails 3 and 7, respectively.
8 is provided. And these top, middle and bottom 3
The book racks are integrally formed with the support frames 1 and 5, with a predetermined distance from each other.

The sheet 9 is stretched between the upper decks 2 and 6,
A connecting piece 19a that connects the seat 9 and a connecting rod 15, which will be described later, is suspended from the center of the lower surface of the seat 9.

The upper parallel link 10 has one end pivotally connected to the mid-piece 3 by an upper pivot joint 12, and the upper parallel link 11
Similarly, one end of the upper parallel links 10 and 11 is pivotally connected to the central rod 7 by an upper pivot joint 13, and the free ends of the upper parallel links 10 and 11 are rotatably connected to each other by a connecting rod 15.

The lower parallel link 20 is formed to have the same length as the upper parallel link 10, and has one end attached to the lower support 4 with the lower pivot joint 22.
The lower parallel link 21 is
It is formed to have the same length as the upper parallel link 11, and one end thereof is pivotally connected to the lower support 8 by a lower pivot pin 23, and the free ends of these lower parallel links 20, 21 are connected to the pivot pin 2.
6, they are rotatably connected to each other.

The intermediate piece 25 has both ends connected to the upper parallel link 1.
0, 11 connecting parts and lower parallel links 20, 21
At the connecting portion, each parallel link 10, 11 and 2 is connected by a connecting rod 15 and a pivot pin 26, respectively.
0 and 21, and are rotatably connected to each other. The distance between the axes between the connecting rod 15 and the pivot pin 26 is such that the upper pivot joint 12 is the pivot joint of the upper parallel link 10 and the lower pivot joint 22 is the pivot joint of the lower parallel link 20. or similarly between the upper pivot joint 13
The length is equal to the distance between the shafts and the lower pivot joint 23.

The support frame 30 is formed to have a length approximately equal to the diagonal length between the connecting portion and the lower pivot joint 22 when the upper parallel links 10 and 11 are extended in a straight line,
One end thereof is pivotally connected to the lower deck 4 by a lower pivot connector 22. Similarly, the support frame 31 is formed to have a length approximately equal to the diagonal length between the connecting portion and the lower pivot link 23, and one end thereof is connected to the lower support 8 by the lower pivot link 23. It is pivoted to the support rod 3.
0 and 31 extend inwardly and upwardly, and their free ends are rotatably connected to each other by a support shaft 32.

This support shaft 32 is fixed to a sliding member 35 that is fitted onto the intermediate piece 25 and is movable up and down. This sliding member 35 accompanies the free end portions of the support rods 30, 31 to the upper part of the intermediate piece 25 when the support frames 1, 5 are farthest apart and the upper parallel links 10, 11 are in a straight line state. The upper surface of the upper parallel link 10 and the connecting portion of the upper parallel links 10 and 11 come into contact with each other in the raised position. Further, when the support frames 1 and 5 are close to each other and the upper parallel links 10 and 11 and the lower parallel links 20 and 21 become chevron-shaped,
The sliding ring 35 is moved to the lower part of the intermediate piece 25 along with the free ends of the support rods 30 and 31.

Upper parallel links 10, 11, lower parallel links 20, 21, intermediate piece 25, and support rods 30, 3.
1. Two sets of sliding members 35 are provided at a predetermined interval at the front and rear parts in the front and back direction of the supporting frames 1 and 5, and the connecting portions of the front and rear upper parallel links 10 and 11 are connected. They are connected by rod 15. Note that 18 and 19 in the figure are wheels.

Next, the folding operation of the wheelchair configured as described above will be explained.

When the support frames 1 and 5 are separated the most and the wheelchair is in use, the upper parallel links 10 and 11 and the lower parallel links 20 and 21 are in a straight line and parallel to each other, as shown in FIG. , the sliding member 35 is located on the upper part of the intermediate piece, and the upper parallel link 1 is provided on the upper surface thereof.
The connecting parts 0 and 11 are in contact with each other. At this time, upper parallel links 10, 11 and lower parallel links 20,
Each connecting portion of 21 is located at a position slightly below the dead center, and furthermore, this upper and lower connecting portion is connected to the intermediate piece 25.
The supporting frames 1 and 5 are connected to each other by the support frames 1 and 5, and the distance between the supporting frames 1 and 5 is maintained stably.

When folding the wheelchair, first lift the center portion of the seat 9 upward. Accordingly, the connecting piece 9a at the center of the seat 9 lifts the connecting rod 15 upward. Due to the upward movement of the connecting rod 15, the upper parallel links 10, 11 and the lower parallel links 20, 21 move away from their dead centers and become chevron-shaped, respectively, and the sliding member 35 and the connecting portion of the upper parallel links 10, 11 are separated. do.

At this time, the supporting frame 1, the upper parallel link 10, the lower parallel link 20, the intermediate piece 25, the supporting frame 5, the upper parallel link 11, and the lower parallel link 21
Two symmetrical parallelograms are formed with the intermediate piece 25 standing upright (see FIG. 3).

Next, when the support frames 1 and 5 are pushed closer together, the upper parallel links 10 and 11 and the lower parallel link 2
0 and 21 become sharper chevrons, respectively, and as shown in FIG.
are the closest positions in parallel.

<Effects of the invention> The wheelchair of this invention has the above-mentioned configuration, in which the left and right support frames are connected by a pair of upper parallel links and a pair of lower parallel links, and the pair of upper parallel links are connected. The connecting portion between the lower parallel link and the pair of lower parallel links is connected by an intermediate piece, and the connecting portion between the pair of upper parallel links is further supported by a sliding member connected to a pair of support rods, thereby increasing the lateral strength of the wheelchair. The strength in the vertical direction is significantly strengthened, and it exhibits stable running performance and high durability over time.

Furthermore, the number of pivot points for each member is reduced, and the number of man-hours required for assembling the wheelchair is reduced.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a wheelchair according to an embodiment of the invention, Fig. 2 is an explanatory view showing the same state of use, and Fig. 3 is a perspective view showing a wheelchair according to an embodiment of the invention.
FIG. 4 is an explanatory view showing the seat in a lifted state, and FIG. 4 is an explanatory view showing the seat in a folded state. 1, 5... Support frame, 9... Sheet, 10, 11...
...Upper parallel link, 20,21...Lower parallel link,
25... Intermediate piece, 30, 31... Support rod, 35...
sliding member.

Claims (1)

[Scope of Claim for Utility Model Registration] A foldable wheelchair, comprising: a pair of support frames each having an upper arm, a middle arm, and a lower arm arranged vertically at a predetermined distance from each other; and both upper arms. a sheet stretched between; a pair of upper parallel links having one end pivotally attached to the central rod and inner free ends rotatably connected to each other by a connecting rod; and a length of the pair of upper parallel links. a pair of lower parallel links each having the same length and having one end pivoted to the lower rung and the inner free ends rotatably connected to each other by a pivot pin; The connecting portion of the pair of upper parallel links and the connecting portion of the pair of lower parallel links are pivotally connected, and the distance between the axes of both the connecting portions is smaller than that of the connecting portion of the upper parallel link to the upper leg. an intermediate piece having a length equal to the distance between the axes of the lower parallel link and the pivot point to the lower rung; and an intermediate piece formed longer than the length of the upper parallel link or the lower parallel link, and one end of which a pair of support rods, which are pivotally connected together with the lower parallel link, and whose free end portions extending upwardly inside the support rods are rotatably connected to each other by a support shaft; a sliding member movably guided in a direction, and a connecting portion thereof is formed so as to come into contact with the sliding member when the pair of upper parallel links are in a straight line state.