JP6371166B2 - Brake actuator - Google Patents

Description

The present invention relates to a brake operation unit provided in a brake mechanism of a wheelchair including a main wheel on which a solid no-puncture tire is mounted.

  As a tire used for a main wheel of a wheelchair, it is known that a solid no-puncture tire which does not use an air tube as described in Patent Document 1, for example, is provided. Such a solid no-puncture tire is an airless tire without a cavity, and an elastomer such as synthetic rubber or a foamed material such as foamed polyurethane is used as the material. A so-called high-polymer tire made of polyurethane foam in which a solid tire body and a bead portion to be fitted in a tire mounting groove of a wheel rim are integrally formed as a no-punctured tire particularly used for a main wheel of a wheelchair. What is called is becoming more and more used because it is lightweight without worrying about punctures.

JP 2006-143187 A

  However, the high polymer tires are softer than conventional rubber tires, so even when brakes are applied and brake shoes or the like bite into the tires, sufficient frictional resistance cannot be obtained. There was room for improvement in the braking performance of the main wheels.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a brake actuating portion that has sufficient frictional resistance and can properly brake a main wheel even in a wheelchair using a solid no-puncture tire.

The present invention is provided in a brake mechanism of a wheelchair provided with a main wheel on which a solid no-puncture tire is mounted, and is a brake operation unit pivotally supported on a main body frame provided in the wheelchair, a brake shoe that is disposed on the front of the outer circumferential surface of the no-sealing tire, the a brake actuating member facing the side peripheral surface of the no-sealing tire, the brake actuating member is a circular plate constituting the brake actuating member body And the one plate surface of the disk portion is a brake plate surface pressed against a part of the side circumferential surface of the no-puncture tire, and the brake plate surface further includes the disk portion. thickness direction and the depth direction, and a circular recess around the central axis of the circular plate portion is formed, when said no-sealing tire attempts to reverse rotation from a stationary state, the brake actuating member With the rotation of the no-sealing tire for contact state, with the brake shoes said brake actuating portion is rotated becomes a state of bites in pressure contact with the no-sealing tire, the brake plate surface is in the no-sealing tire in pressure state, and the inner peripheral surface and the circular recess around the circular recess is pressed against the outer peripheral surface of the no-sealing tire, the main wheels is a brake actuating part, characterized in that it is braked.

  By providing a circular recess in the brake plate surface as in this configuration, the brake plate surface is not a simple smooth surface but has a step shape. For this reason, when the brake plate surface is pressed against the no-puncture tire, the no-puncture tire is deformed corresponding to the step shape, thereby increasing the contact area between the brake plate surface and the no-puncture tire, The braking performance is improved as compared with the conventional one, and the rotation of the main wheel can be surely suppressed.

  In addition, a central convex portion protruding toward the no-puncture tire is provided at the center of the circular concave portion, and a bottom surface in the circular concave portion is inclined downward toward the central convex portion, and the brake A configuration is proposed in which when the plate surface is in pressure contact with the no-puncture tire, the center convex portion and the bottom surface of the circular convex portion are in pressure contact with the outer peripheral surface of the no-puncture tire.

  By adopting a configuration in which the central convex portion comes into contact with the no-puncture tire as in this configuration, the pressure when pressed against the no-puncture tire by the central convex portion is increased, and the central convex portion is against the no-puncture tire. The frictional resistance generated between the brake plate surface and the no-puncture tire can be improved by strongly pressing. In addition, if the bottom surface of the inner circumferential surface of the circular concave portion is inclined downward toward the central convex portion, it becomes possible to maximize the protruding height of the central convex portion in the thickness of the disc portion. This makes it possible to press the central convex portion more strongly against the no-puncture tire.

The brake actuating portion of the present invention can greatly increase the frictional resistance generated between the brake tire and the no-puncture tire, and thus has an effect of improving the braking performance of the main wheel using the no-puncture tire.

It is a side view of a wheelchair. It is an enlarged side view which shows the brake mechanism of a wheelchair. The member for a brake action is shown, (a) is a front view, (b) is a side view, (c) is the sectional view on the AA line of (a). It is a side view which shows the state which exists in the brake mechanism of a wheelchair and the wheel is rotating forward. It is an outline explanatory view showing a pair of left and right brake actuating members provided in a wheelchair brake mechanism. FIG. 2 is a side view showing a braking state (braking state) in a wheelchair brake mechanism. It is sectional drawing which shows a left-right paired brake action member which shows a braking state. It is sectional drawing which shows the member for brake actuation concerning another Example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying a brake operating unit provided in a wheelchair brake mechanism according to the present invention will be described in detail below. In addition, this invention is not limited to the Example shown below, A design change is possible suitably.

  As shown in FIG. 1, the wheelchair 1 includes a main body frame 10 made of a metal pipe. The main body frame 10 includes a pair of left and right side frames 10A and 10A. The side frame 10A includes a base frame portion 11 formed in the front-rear direction, a rear leg frame portion 12 rising from the base frame portion 11, and the It has a back frame portion 13 that extends further upward from the rear leg frame portion 12 and a seat frame portion 15 that extends forward and horizontally from the upper end portion of the rear leg frame portion 12. The side frames 10A and 10A are connected by a pair of front and rear X frame frames 17 and 17, and further, a seat cloth (illustrated) attached to an upper ridge 16 spanned between the upper end portions of the X frame frames 17 and 17. The omission) forms a seating portion 18.

  Further, a handle portion 14 for an assistant to operate the wheelchair 1 is formed at the upper end of the back frame portion 13. Further, a front frame portion 25 is bridged between the base frame portion 11 and the front end portion of the seat frame portion 15, and a caster 26 as a front wheel is attached to the lower end of the front frame portion 25. It has been. Further, a foot frame 27 is attached from the front frame portion 25 toward the front side, and a footrest 28 is attached to the foot frame 27.

  The rear leg frame 12 is provided with a rotating shaft portion 3 to which a main wheel on which a no-puncture tire 2 is mounted is connected to the rotating shaft portion 3. The no-puncture tire 2 is formed of a solid molded product of solid foamed polyurethane.

  Next, the configuration of the wheelchair brake mechanism 30 for braking the main wheel will be described in detail with reference to FIG.

  The wheelchair brake mechanism 30 includes a brake operation unit 50 that is pivotally supported by a base plate 40 provided in the base frame unit 11, and the brake operation unit 50 faces the front side of the no-puncture tire 2 in the main wheel. .

  More specifically, as shown in FIG. 2 and the like, the brake operation unit 50 includes a brake base portion 52 made of a U-shaped member and a plate-like cam portion 53 connected to the brake base portion 52. Yes. The brake base 52 includes a substantially horizontal bottom plate portion 523 and a pair of left and right roller holding plate portions 521 and 521 rising from both the left and right sides of the bottom plate portion 523. The no-puncture tire 2 is inserted between the pair of left and right roller holding plate portions 521 and 521, whereby the brake shoe 56 formed at the tip of the bottom plate portion 523 is connected to the outer peripheral surface of the no-puncture tire 2 ( Specifically, it is arranged in front of the tread surface) and can be pressed.

  Further, as shown in FIG. 2, guide long holes 521a and 521a are respectively provided in the roller holding plate portions 521 and 521 in a penetrating manner. Then, both end portions of the roller 60 are inserted into the guide long holes 521a and 521a, respectively, whereby the roller 60 is rotatably held between the roller holding plate portions 521 and 521. Further, the arrangement position of the roller 60 is set such that the roller 60 is always in contact with the no-puncture tire 2. Thereby, the roller 60 can rotate according to the rotation of the tire 2.

  Further, an elastic spring (biasing means) 70 is stretched between the cam portion 53 and the base plate 40 so that the brake shoe 56 is pressed against the no-puncture tire 2. The brake operating unit 50 is biased toward the direction.

Further, as shown in FIGS. 2 and 5, a pair of left and right brake operations facing the side peripheral surface of the no-puncture tire 2 are provided at the distal ends of the pair of left and right roller holding plate portions 521 and 521 in the brake operation unit 50. The members 100 are attached so as to face each other. The brake actuating member 100 preferably has a brake pad shape and is made of rubber such as ABS rubber.

As shown in FIG. 3, the brake actuating member 100 has a disc part 101 that constitutes a brake actuating member main body, and one plate surface of the disc part 101 has a side circumference of the no-puncture tire 2. The brake plate surface 101a is pressed against the surface.

  Further, the brake plate surface 101 a is formed with a circular recess 110 having the thickness direction of the disc portion 101 as the depth direction and the center axis CL of the disc portion 101 as the center. The circular recess 110 is formed with a step surface 111 that hangs down from the brake plate surface 101a along a center axis CL, and a bottom surface 112 that is inclined downward from the step surface 111 toward the center axis CL. At the center of the circular concave portion 110, a central convex portion 120 that protrudes toward the no-puncture tire 2 along the central axis CL is provided.

  On the other hand, a cylindrical shaft portion 102 extends from the back surface 101 b of the disc portion 101. As shown in FIGS. 2 and 5, after the shaft portion 102 is inserted into the through hole 522 provided in each roller holding plate portion 521, the end of the shaft portion 102 is heated and melted to expand the diameter. The roller holding plate 521 is assembled and fixed without dropping off.

Next, the operation mode of the wheelchair brake mechanism 30 will be described in detail.
As shown in FIG. 2, when the main wheel is stationary, the roller 60 in contact with the no-puncture tire 2 is in a non-rotating state. The brake shoe 56 is applied to the tread surface of the no-puncture tire 2 according to the urging force of the coil spring 70.

In the above configuration, as shown in FIG. 4, when the no-puncture tire 2 rotates forward (forward rotation), the roller 60 is pressed downward by friction with the tread surface of the no-puncture tire 2 that rotates forward. The guide long hole 521a is abutted against one end of the guide long hole 521a according to the guiding action of the guide long hole 521a. Then, the brake operating unit 50 rotates against the urging force of the coil spring 70, whereby the brake shoe 56 is separated from the tread surface of the no-puncture tire 2. At this time, as shown in FIG. 5, the pair of left and right brake actuating members 100, 100 in the brake actuating unit 50 are located away from the no-puncture tire 2.

On the other hand, as shown in FIG. 6, when the no-puncture tire 2 tries to reversely rotate from a stationary state, the roller 60 moves upward with the rotation of the no-puncture tire 2. Accordingly, the brake operating portion 50 is rotated according to the guide action of the guide long hole 521a and the urging force of the coil spring 70, so that the brake shoe 56 is brought into pressure contact with the tread surface of the no-puncture tire 2. . At the same time, the brake actuating member 100 is brought into a pressed state (see FIG. 7b) from a state where the brake actuating member 100 is in contact with the no-puncture tire 2 (see FIG. 7a). More specifically, by providing the circular recess 110 in the brake plate surface 101a as in the above configuration, the brake plate surface 101a is not simply a smooth surface but has a step shape. For this reason, when the brake plate surface 101a is in pressure contact with the no-puncture tire 2, the no-puncture tire 2 is deformed corresponding to the stepped shape. The area is increased, the braking performance is improved as compared with the prior art, and the rotation of the main wheel can be reliably suppressed. Specifically, the side peripheral surface of the no-puncture tire 2 abuts on the bottom surface 112 of the inner peripheral surface of the circular recess 110, the step surface 111, and the periphery of the circular recess 110. In particular, the frictional resistance generated between the brake plate surface 101 a and the no-puncture tire 2 is further improved by the central projection 120 provided in the circular recess 110 being strongly pressed against the no-puncture tire 2.

As another embodiment, brake actuating members 130 and 150 as shown in FIG. 8 are proposed. Specifically, as shown in FIG. 8a, the central convex portion 120 may not be provided in the circular concave portion 140. Moreover, as shown in FIG. 8b, the bottom surface in the circular recessed part 150 may be orthogonal to the central axis CL and may not be inclined. Furthermore, the circular recesses 110, 140, and 160 described so far may have other cross-sectional shapes. However, it is desirable that the brake plate surface 101a is constituted by a plurality of surfaces constituted by the periphery of the circular recesses 110, 140, 160 and the inner peripheral surface of the circular recesses 110, 140, 160.

Moreover, the structure provided with the member 100 for a single brake action with respect to the single no-puncture tire 2 may be sufficient. However, a configuration in which braking is performed by sandwiching the no-puncture tire 2 from both sides with a pair of left and right brake actuation members 100 is preferable from the viewpoint of increasing frictional resistance. Of course, the wheelchair brake mechanism 30 may have another structure.

DESCRIPTION OF SYMBOLS 1 Wheelchair 2 No puncture tire 30 Wheelchair brake mechanism 100 Brake operation member 101 Disk part 101a Brake plate surface 110 Circular recessed part 112 Bottom 120 Central convex part 130 Brake operating member 140 Circular recessed part 150 Brake operating member 160 Circular recessed part

Claims (2)

It is provided in a brake mechanism of a wheelchair including a main wheel on which a solid no-puncture tire is mounted, and is a brake operation unit supported on a main body frame provided in the wheelchair,
A brake shoe disposed in front of the outer peripheral surface of the no-puncture tire;
A member for operating a brake facing a side peripheral surface of the no-puncture tire ;
With
The brake actuating member has a disc part that constitutes a brake actuating member main body, and one plate surface of the disc part is pressed against a part of a side peripheral surface of the no-puncture tire. Further, a circular recess is formed on the brake plate surface with the thickness direction of the disc portion being the depth direction and centering on the central axis of the disc portion,
When the no-puncture tire tries to reversely rotate from a stationary state, the brake actuating portion rotates as the no-puncture tire rotates with the brake actuating member in contact with the brake shoe, and the brake shoe does not puncture. with a state of bites in pressure contact with the tire, in a state in which the brake plate surface is pressed against the said no-sealing tire, the inner peripheral surface and the circular recess around the circular recess is pressed against the outer peripheral surface of the no-sealing tire The brake operating unit is characterized in that the main wheel is braked. At the center of the circular recess, a central convex portion that protrudes toward the no-puncture tire is provided, and a bottom surface in the circular concave portion is inclined downward toward the central convex portion,
2. The brake operating unit according to claim 1, wherein when the brake plate surface is in pressure contact with the no-puncture tire, the central convex portion and the bottom surface of the circular convex portion are in pressure contact with the outer peripheral surface of the no-puncture tire.

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