JPH0351423B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a folding mechanism for a wheelchair configured to rotate horizontally to fold the wheelchair.

<Prior Art> In general, a foldable wheelchair is configured to be foldable by connecting opposing left and right side frames with cross braces that are rotatable in the horizontal or vertical direction (for example, −502176
(Refer to Utility Model Publication No. 52-52364).

<Problems to be Solved by the Invention> However, in the folding mechanism of a wheelchair with such a conventional configuration, since the left and right side frames are mainly connected by diagonal cross braces, the lateral direction of the wheelchair There was a problem that the strength of the wheels was weak and the running stability was reduced.

Therefore, for example, in Japanese Patent Publication No. 61-33590, the front and rear toggle braces are pivotally attached to the left and right side frames, respectively, and the related hinges of both toggle braces are connected by fixed links, and the horizontal and vertical directions are A wheelchair folding mechanism with enhanced strength has been proposed.

However, with this type of folding mechanism, when the wheelchair is in use, the expanded side frames are supported only by the tension of the toggle braces, so the rigidity is still insufficient. Nakatsuta.

Furthermore, when folding or unfolding, the left and right side frames have no relationship, so opening and closing operations become unsmooth, and it is necessary to operate the left and right side frames separately.

Japanese Utility Model Publication No. 56-18333 also describes a yoke consisting of a pair of pipes pivotally connected at the center, left and right frames fixed to the left and right upper and lower ends of the yoke, and fixed to the left and right frames respectively. A folding mechanism for a wheelchair has been proposed, which includes a guide rail having a long hole, and a hubshaft that is movably provided in the long hole and can be locked to the guide rail, and the hubshaft is connected to a seat pipe via a connecting rod. There is.

In this mechanism, the left and right frames are folded via the yoke, and the connecting rod and hubshaft do not have the purpose or effect of opening and closing the left and right frames, but rather contribute to smooth opening and closing operations. It wasn't.

The present invention has been made in view of the above, and aims to provide a folding mechanism for a wheelchair that has strong strength in the lateral and vertical directions, has great running stability, and can smoothly open and close the folding mechanism. It is.

<Means for Solving the Problems> The present invention has been made to achieve the above object, and includes a pair of side frames facing each other on the left and right, the inner end portions of which are each pivotally connected to a front joint block, and the outer end a pair of front swing members whose parts are pivotally connected to the left and right side frames so as to be rotatable in the horizontal direction; a pair of rear swing members which are pivotally connected to the rear joint block and whose outer ends are pivotally connected to the left and right side frames, respectively, so as to be rotatable in the horizontal direction; and the front joint block and the rear joint block. a center joint that connects the
A folding mechanism for a wheelchair comprising: a stop joint that is movable in the axial direction of the center joint and that is fixed to the center joint at a position where the left and right side frames are most distant from each other; a pair of support members, each of which has an inner end pivotally connected to the stoppage joint and an outer end pivotally connected to the left and right side frames so as to be rotatable in a horizontal direction. It is a folding mechanism.

<Function> The present invention is configured as described above, and the left and right side frames, the pair of front swing members, the pair of rear swing members, the center joint, and the support member are arranged in the center joint. A symmetrical parallel link mechanism that rotates in the horizontal direction is formed with the axis of symmetry as the axis of symmetry.

Then, when the left and right side frames are brought close to each other or separated from each other, the left and right side frames are brought close to each other or separated from each other in a parallel state, and the stopper joint is moved by the support member and moves on the center joint. At the position where the left and right side frames are farthest apart, the movement of the stop joint is fixed by the locking device, and the separated state is maintained.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

1 to 6 show an embodiment of the present invention. In the figures, reference numerals 1 and 5 are wheelchair frames placed opposite each other, and side frames extending in the front-rear direction at a predetermined interval above and below, respectively. 2A, 2B and 6A, 6B.

The folding mechanism of the wheelchair according to the present invention has its inner ends pivoted to the front joint blocks 20, and its outer ends pivoted to the side frames 2A, 2B and 6, respectively.
A pair of front swing members 1 pivotally connected to A and 6B
1, 15, a pair of rear swing members 31, 35 whose inner members are each pivotally connected to the rear joint block 40, and whose outer ends are pivotally connected to the side frames 2A, 2B and 6A, 6B, respectively; A center joint 46 that connects the int block 20 and the rear joint block 40, a stop joint 50 that moves on the center joint 46, and a stop joint 50 and the side frames 2B, 6B. The main components are a pair of support members 61 and 65 whose ends are pivotally connected, and a lock device 70 that can fix the movement of the stop joint 50.

Front swing members 11, 15, rear swing member 3
1 and 35 are each formed into an irregular trapezoid shape in the embodiment, and vertical through holes (not shown) for pivoting are provided at the inner and outer ends thereof.

The inner ends of the front swing members 11, 15 are rotatably attached to and connected to the front joint block 20 by shafts 24, 25, respectively, and the outer ends thereof are connected to the front joint blocks 20, respectively. It is rotatably mounted in the horizontal direction by shafts 14 and 18, respectively, on pivot joints 12 and 13 provided at predetermined positions and pivot joints 16 and 17 provided at predetermined positions of the side frames 6A and 6B. There is.

The inner end portions of the rear swing members 31, 35 are rotatably attached to and connected to the rear joint block 40 by shafts 44, 45, respectively, and the outer end portions are attached to predetermined positions of the side frames 2A, 2B. It is rotatably attached in the horizontal direction by shafts 34 and 38, respectively, to pivot joints 32 and 33 provided on the side frames 6A and 6B, and to pivot joints 36 and 37 provided at predetermined positions on the side frames 6A and 6B.

In the embodiment, the center joint 46 is made of a tubular member, and has a locking hole 47 at a predetermined position.
front joint block 20 from the front and rear ends, respectively;
It is fixed to the rear joint block 40. The center distance between the front joint block 20 and the rear joint block 40 is equal to the distance between the shafts 14 and 34 and the distance between the shafts 18 and 38. Furthermore, between the front joint block 20 and the rear joint block 40,
A guide member 48 is installed above and parallel to the center joint 46.
A stopper joint 50 is externally fitted onto the guide member 6 and the guide member 48 so as to be movable in the axial direction thereof.

The stopper joint 50 has a sliding hole 51 through which the center joint 46 passes and a guide hole 52 through which the guide member 48 passes, and has a vertical direction for pivotally mounting the support members 61 and 65 at predetermined positions. A through hole (not shown) is bored.

In the embodiment, the support members 61, 65 are connected to a stop joint 50 which is in contact with the pivot joints 33, 37 and the front joint block 20 when the side frames 2A, 2B and 6A, 6B are furthest apart. and its outer end is formed to have a length equal to the diagonal length between the axes 34, 38.
are respectively attached to the pivot joints 33 and 37 so as to be rotatable in the horizontal direction, and the inner end portions are respectively attached to the shaft 5.
8 and 59, it is pivotally connected to the stopper joint 50. And side frames 2A, 2B
As 6A and 6B approach each other, the stop joint 50 is moved relatively backward on the center joint 46.

The lock device 70 is provided between the center joint 46 and the stop joint 50, and is configured to be able to fix the movement of the stop joint 50, which is in contact with the front joint block 20.

That is, the protrusion 53 of the stopper joint 50
has a pin hole (not shown in the figure) that opens downward, and the tip is connected to the center joint 4.
A stopper pin 55 that can be engaged with the locking hole 47 of No. 6
is internally biased downward by a spring 57. Further, a socket 75 is fixed to the front end of the center joint 46.
, there is a push-up pin 7 having a conical head at the tip.
2 is fixed, and a release button 71 biased outwardly by a spring 73 is provided so as to be movable in the axial direction.

And side frames 2A, 2B and 6
The stopper pin 55 is formed so as to engage with the locking hole 47 and fix the position of the stopper joint 50 when A and 6B are the most distant from each other. Further, by pushing the release button 71, the push-up pin 72 pushes the stopper pin 55 upward against the spring force of the spring 57. This releases the engagement between the stopper pin 55 and the locking hole 47, allowing the folding mechanism to fold.

Next, the operation of the wheelchair folding mechanism configured in this manner will be explained.

When the frames 1 and 5 are farthest apart and the wheelchair is in use, as shown in FIGS. 1 and 2, the front swing members 11 and 15 and the rear swing member 3
1 and 35 are in a straight line and parallel to each other, and the stop joint 50 is connected to the center joint 46.
It is in contact with the front joint block 20 at its front end. At this time, the locking device 70 locks the stop joint 50 and the center joint 4.
6 are engaged with each other, and the distance between the frames 1 and 5 is maintained stably.

When folding the wheelchair, first press the release button 71 and release the stop joint 5.
0 and the center joint 46,
Pull the front joint block 20 forward. Along with this, the front swing members 11, 15 and the rear swing members 31, 35 escape from their dead centers and protrude forward in a chevron shape, and the stopper joint 50 accompanies the support members 61, 65 to the front swing member 31, 35. It separates from the int block and moves over the center joint 46 toward the rear joint block 40.

The support members 61 and 65 are symmetrically connected via the stopper joint 50,
It operates to bring the side frames 2A, 2B and 6A, 6B evenly close to each other.

At this time, the side frames 2A, 2B, the front swing member 11, the rear swing member 31, and the side frames 6A, 6B, the front swing member 15, and the rear swing member 35 are arranged horizontally with the center joint 46 as an axis of symmetry. form a parallelogram. Subsequently, when the frames 1 and 5 are pushed closer to each other, the two parallelograms are further tilted, and each member is brought into close contact with each other as shown in FIG. Frames 1 and 5 are at the closest positions.

6 and 7 show another embodiment of this invention, which is characterized by the structure of the support member. In addition,
In the following explanation, the same components as in the first embodiment are:
The same reference numerals are used to omit the explanation.

Stopper joint 50 of this second embodiment
is fixed to the outer end of a slide pipe 78 that is fitted into the center joint 46 and is slidable in the axial direction thereof. Support members 61, 65
, each inner end is the front swing member 11,1
5. The rear swing members 31 and 35 are pivotally connected to a stop joint 50 on the outside of the quadrilateral formed by the rear swing members 31 and 35, and the outer ends are pivotally connected to the side frames 2B and 6B by shafts 34 and 38.

According to this configuration, the side frames 2A, 2B
It can be folded by pushing the front joint block 20 backward from the state where the front support members 11, 15, the rear swing members 31, 35, and the support members 61, 6 are separated from each other.
5 has a shape that protrudes rearward.

In addition, in this structure, as shown in FIG. 8, when folded, the front swing members 11, 15 and the rear swing members 31, 35 can be drawn forward, and the support member can be made to protrude rearward.

9 to 12 show a third embodiment of this invention, which is characterized by the shape of the support member.

Support members 61A and 65A of this third embodiment
is formed into an irregular trapezoidal shape similar to the front swing members 11, 15 and the rear swing members 31, 35. The outer and inner ends of the support members 61A, 65A are connected to the shafts 34, 38 and 58, respectively.
59 to side frames 2A, 2B and 6A, 6
B and the stopper joint 50 at two points, upper and lower, to form a folding mechanism that is further strengthened against twisting. In addition, 7
Reference numeral 9 denotes a stopper pipe that is fitted onto the center joint 46 and defines the movement of the stopper joint 50.

13 and 14 show a fourth embodiment of the invention, which is characterized by a relatively short support member.

The support members 61 and 65 of this fourth embodiment are
When the side frames 2A, 2B and 6A, 6B are farthest apart, the stopper joint 50 at the inner end thereof has a length that is located approximately at the center of the center joint 46 in the longitudinal direction, and A stopper pipe 79 that defines the movement of the stopper joint 50 is fitted onto the center joint 46 on the front joint block 20 side.

The locking devices in the second to fourth embodiments can be applied by adjusting the position of the push-up pin 72 of the locking device 70 in the first embodiment.

Further, the present invention is not limited to the above description and illustrated examples, and the embodiments thereof can be changed without departing from the technical idea of the present invention. For example, the front and rear swing members and the support member may be formed from plate materials or framed by pipe materials.

Furthermore, in addition to the locking hole for locking the frame when it is separated, a locking hole for locking the frame in the folded state may be added.

<Effects of the Invention> The wheelchair folding mechanism according to the present invention has the above-described configuration, in which the left and right side frames have a pair of front swing members that rotate horizontally in parallel with each other, and a pair of rear swing members that rotate horizontally in parallel with each other. Since the support member is connected to the swing member and is fixed as a diagonal member between the left and right side frames in the most separated state, the lateral strength and vertical strength of the wheelchair are significantly strengthened, making it stable. It can exhibit excellent running performance and maintain high durability over time.

In addition, the pair of support members are interlocked with each other via stoppage joints, and act to equally move the left and right side frames closer to each other and separate them, allowing for smooth folding operation and operation of one side frame. Opening/closing operations can be easily performed using the .

In addition, since the folding mechanism rotates horizontally and folds, the folding operation becomes easier, and the center of gravity is lowered when folded and stored, improving the stability of hem placement. .

[Brief explanation of drawings]

FIG. 1 is a perspective view of a folding mechanism of a wheelchair according to an embodiment of the present invention, FIG. 2 is a plan view, FIG. 3 is a front view, and FIG. 4 is a sectional view of the center joint and locking device. 5 is a plan view showing the folded state, FIG. 6 is a plan view showing the second embodiment, and FIG. 7 is a plan view showing the folded state.
Fig. 8 is a plan view showing another folding mode, Fig. 9 is a plan view showing the third embodiment, Fig. 10 is a side view, Fig. 11 is a front view, and Fig. 12 is a folded state. 13 is a plan view showing the 4th
FIG. 14 is a plan view showing the embodiment, and FIG. 14 is a plan view showing the folded state. 2A, 2B, 6A, 6B...Side frame,
11, 15...front swing member, 20...front joint block, 31, 35...rear swing member, 40...rear joint block, 46...center joint, 50...stopper joint, 61 , 65... support member, 70... locking device.

Claims (1)

[Scope of Claims] 1 A pair of side frames facing each other on the left and right, the inner end portions of which are each pivotally connected to the front joint block, and the outer end portions of which are each pivotally connected to the left and right side frames and rotate in the horizontal direction. a pair of front swing members that are arranged in parallel at the rear of the front swing members, inner ends of which are pivotally connected to the rear joint blocks, and outer ends of which are respectively connected to the left and right side frames; A folding mechanism for a wheelchair, comprising: a pair of rear swing members pivotally connected to the rear swing members, and a center joint connecting the front joint block and the rear joint block. a stop joint that is movable in the axial direction of the center joint and that is fixed to the center joint at a position where the left and right side frames are farthest from each other; A folding wheelchair characterized by comprising: a pair of support members pivotally connected to a stoppage joint, and having outer end portions pivotally connected to the left and right side frames, respectively, so as to be rotatable in a horizontal direction. mechanism.