JP2015217018A - Brake for wheelchair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate a wheelchair with a smaller force than before. SOLUTION: A pressing portion 32A presses a tire by changing the positions of a pin 50 connecting an operation lever 30, a tire pressing member 32 having a pressing portion 32A for pressing the tire 18, and a first arm 34A and a second arm. Separates the connecting arm 34, which is rotatably supported by the pin 50, the engaging portion 38 formed at the tip of the operating lever, and the pressing portion 32A from the tire 18. A lever is provided with a urging means 40 for urging in the direction, and the shape of the engaging portion 38 is such that the distance from the force point X of the lever holding the ha operating lever 30 to the center of the pin 42 which is the fulcrum P of the lever is A. When the distance from the fulcrum P of the lever to the center 50 of the rotating body 36, which is the point of action Q of the lever, is set to B, the lever ratio B / A becomes smaller as the operating lever 30 is rotated in the braking operation direction. It is formed. [Selection diagram] Fig. 2

Description

  The present invention relates to a wheelchair brake, and more particularly to a brake suitable for a resin tire in which a wheelchair tire is harder than a rubber tire.

  Regardless of whether it is electric or self-propelled, nursing wheelchairs are provided with manual wheelchair brakes to enhance safety. As this wheelchair brake, a toggle brake is generally used. The toggle brake includes an operation lever, a link mechanism, and a tire pressing member. Then, when the user or the assistant on the wheelchair rotates the operation lever in the brake operation direction, the tire pressing member moves toward the tire side by the link mechanism and presses the tire. As a result, a brake structure is applied in which the tire is braked (for example, Patent Document 1).

  This brake operation is not limited to braking so that the wheelchair does not move in a flat place in the house or outdoors, but is also used for braking so that the speed does not excessively go downhill. Such a braking operation on a slope is a heavy burden for a wheelchair user and involves a risk of wheelchair runaway.

  Therefore, it is important for a wheelchair user to reliably brake the tire with a small force without applying a large force to the operation lever to perform a brake operation.

Japanese Patent Application Laid-Open No. 2001-314452

  However, a conventional wheelchair brake cannot be reliably braked on a tire when a wheelchair user applies a small force to an operation lever, and an improvement is desired.

  By the way, resin tires, which are said to be no-puncture tires, are now used for wheelchair tires. This resin tire is one in which a foamed urethane resin is inserted into the tire or filled with a gel resin, and has a property that it is harder than a rubber tire in which air is injected into a conventional tire.

  Therefore, particularly in the case of a wheelchair using a resin tire, a larger force than before is required for the wheelchair user to surely push the tire pressing member into the tire, which is a heavy burden on the user. Further, when a braking operation is performed simultaneously on both the left and right tires of the wheelchair, a greater force is required.

  The present invention has been made in view of such circumstances, and a wheelchair user can perform a brake operation with a smaller force than before, particularly when the wheelchair is using a resin tire having a hard property or a wheelchair. An object of the present invention is to provide a wheelchair brake that is suitable when the brake operation is performed simultaneously on both the left and right tires.

  In order to achieve the above object, a wheelchair brake according to the present invention is a wheelchair brake that applies brakes to wheelchair tires and pivots via a first pin on a bracket provided on a body frame of the wheelchair. A control lever that is freely supported, a tire pressing member that has a base end portion rotatably supported by the bracket via a second pin, and that has a pressing portion that presses the tire at a distal end portion; A first arm having one end rotatably supported via 3 pins, and one end rotatably supported via a fourth pin on the tip end side of the tire pressing member and the other end being the first The second arm is rotatably connected to the other end of the arm via a fifth pin, and the pressing portion of the tire pressing member is separated from the tire by changing the position of the fifth pin. A connecting arm, a rotating body rotatably supported by the fifth pin, and a distal end portion of the operation lever. The rotating body engages with the rotating body and moves according to the engagement shape. And an urging means for urging the pressing portion of the tire pressing member in a direction away from the tire, and the shape of the engaging portion is , A is the distance from the leverage point of the lever gripping the operating lever to the center of the first pin that is the fulcrum of the lever, and B is the distance from the fulcrum of the lever to the center of the rotating body that is the point of action of the lever. In this case, the lever ratio B / A is reduced as the operating lever is rotated in the brake operating direction.

  According to the wheelchair brake of the first embodiment of the present invention, the engaging portion is formed at the distal end portion of the operating lever that acts as a lever with the first pin as a fulcrum. In addition, the rotating body was supported by the fifth pin of the connecting arm for separating the pressing portion of the tire pressing member from the tire. The rotating body is engaged with the engaging portion.

  That is, when the operating lever is rotated, the rotating body moves following the shape of the engaging portion, and the pressing portion of the tire pressing member comes in contact with the tire while changing the position of the fifth pin. . In this case, the rotating body is pressed against the engaging portion by the urging force of the urging means that urges the pressing portion in a direction away from the tire.

  The shape of the engaging portion is defined as A, where the distance from the lever's power point at which the user of the wheelchair holds the control lever to the lever's fulcrum, which is the central axis of the first pin, from the lever's fulcrum to the center of the rotating body (first When the distance to the lever action point, which is synonymous with the center of the 5-pin) is B, the lever ratio B / A is reduced as the operating lever is rotated in the brake operation direction. That is, the brake operation can be performed with a small force as the brake operation by the operation lever approaches from the start to the end.

  Thereby, the user can perform a brake operation with a smaller force than before. In particular, even when the wheelchair is a resin tire that is harder than the rubber tire or when the brake operation is simultaneously performed on both the left and right tires of the wheelchair, the brake operation can be performed with a small force.

  Although the distance from the fulcrum of the lever to the center of the rotating body, which is the point of action of the lever, is B, the contact point where the engaging portion of the operating lever and the rotating body come into contact is the point of action, and the contact from the fulcrum of the lever The same applies when the distance to the point is B.

  As an aspect of the present invention, the rate at which the lever ratio B / A decreases as the operating lever is rotated in the brake operating direction is greater than the contact of the pressing portion of the tire pressing member with the tire. It is preferable that the time when the pressed portion is pushed into the tire is larger.

  Accordingly, the lever ratio B / A can be further reduced when the pressing portion of the tire pressing portion that requires the greatest force in the brake operation is pressed after contacting the tire.

  As an aspect of the present invention, when an angle of a stroke for rotating the operation lever in the brake operation direction is an input angle, and a stroke of the tire pressing member that rotates with the rotation of the operation lever is an output angle, The output angle from when the pressing portion of the tire pressing member comes into contact with the tire to when it is pushed into the tire and the brake operation is completed is preferably 40% to 60% of the total output angle of the tire pressing member.

  Strictly speaking, since the tire is not a perfect circle but slightly distorted, the amount of pushing the pressing portion into the tire changes depending on the tire position, and the braking performance changes.

  However, by configuring as in the aspect of the present invention, it is possible to increase the amount by which the pressing portion of the tire pressing portion is pressed into the tire, so that the tire can be reliably braked. In this case, even if the stroke of the operation lever when pushing the pressing portion into the tire becomes large, the lever ratio B / A when pushing is small, so the burden on the user is not increased.

As an aspect of the present invention, it is preferable that the engaging portion is a curved concave portion that is concavely cut out at a distal end portion of the operation lever.
This shows one aspect of the shape of the engaging portion for reducing the lever ratio B / A as the operating lever is rotated in the brake operating direction.

As an aspect of the present invention, it is preferable that the engaging portion is a curved long hole formed at a distal end portion of the operation lever.
This shows another aspect of the shape of the engaging portion for reducing the lever ratio B / A as the operating lever is rotated in the brake operating direction.
Thus, by making the shape of the engaging portion a curved long hole, the risk of disengagement between the engaging portion and the rotating body can be reliably prevented.

  As an aspect of the present invention, when the operation lever is rotated in the brake operation direction, the side surface of the operation lever comes into contact with the base end portion of the tire pressing member, so that the brake operation is completed, and the operation lever It is preferable that a curved notch is formed in the contact portion.

  In this way, by forming the curved notch at the contact portion of the operation lever, a large rotation angle of the operation lever can be ensured, so that the pressing portion can be pushed deeply into the tire. Thereby, a brake operation can be performed reliably.

As an aspect of the present invention, the first arm is preferably formed in a curved shape.
In this way, by forming the first arm in a curved shape, the first arm can be prevented from hitting the first pin, so that a large stroke of the operation lever can be ensured.

In order to achieve the above object, a wheelchair brake according to the present invention is a wheelchair brake that applies brakes to wheelchair tires and pivots via a first pin on a bracket provided on a body frame of the wheelchair. An operation lever that is freely supported, a tire pressing member that has a base end portion rotatably supported by the bracket via a second pin, and a pressing portion that presses the tire at a distal end portion, and the tire pressing member The tire holding member by changing the engagement position with respect to the elongated hole by rotating the operating lever. And an engaging pin that separates and contacts the pressing portion of the tire with respect to the tire. When the distance to the point of action of the pressing portion that presses the tire is a, and the distance from the fulcrum of the lever to the center of the engaging pin of the operating lever that is the force point of the lever is b, The lever ratio b / a is formed so as to increase as the brake is rotated in the brake operation direction.
According to the wheelchair brake of the second embodiment, the engagement pin provided at the tip of the operation lever that rotates about the first pin and the tire pressing member that rotates about the second pin are formed. The lever ratio b / a is increased as the elongated lever is engaged and the operation lever is rotated in the brake operation direction.
As a result, at the start of the brake operation of the control lever, the distance from the fulcrum to the force point of the tire pressing member is small, and the distance from the force point to the action point is large, so a large movement is generated at the action point by a small movement applied to the force point. Can be made. Therefore, the pressing portion of the tire pressing member can be brought into contact with the tire with a small rotation of the operation lever.
Then, as the brake operation ends, the distance from the fulcrum of the tire pressing member to the force point gradually increases, and the distance from the force point to the action point gradually decreases. As a result, the force applied to the force point is greatly applied to the action point. Therefore, even if the operation lever is operated with the same force as when the brake operation is started, a larger force is applied at the action point than when the brake operation is disclosed. be able to. That is, the brake operation can be performed with a small force as the brake operation by the operation lever approaches from the start to the end.
Moreover, since the pressing portion of the tire pressing member can be brought into contact with the tire by a small rotation of the operating lever at the stage of starting the brake operation, the operation lever can be rotated until the pressing portion is pressed into contact with the tire. It can be secured greatly. Thereby, a brake can be reliably applied to a tire.
Accordingly, the wheelchair brake of the second embodiment can be reliably operated by the user with a smaller force than before.

In the wheelchair brake according to the second embodiment, it is preferable that the tire pressing member is formed in a dogleg shape in which the tire side is recessed.
Thereby, at the time of a brake operation start, the press part of a tire pressing member can be made to contact | abut to a tire by much smaller rotation of an operation lever.

  As an aspect of the present invention, it is preferable that the brake is provided on each of the left and right wheels of the wheelchair, and each brake is connected by a power transmission mechanism.

  Since the wheelchair brake of the present invention can be braked with a small force, the burden on the user does not increase even if the left and right control levers are braked simultaneously with either left or right operation lever.

In order to achieve the above object, a brake for a wheelchair according to the present invention is applied once to both the left and right wheels by operating either the first brake or the second brake provided on the left and right wheels of the wheelchair. A brake for a wheelchair provided with a power transmission mechanism that applies a brake to the outer wire, wherein the power transmission mechanism has one end of the inner wire provided on the operation lever of the first brake to hold one end of the outer wire. The outer wire holder is fixed to a bracket that supports the first brake via a holder, and the other end of the inner wire is connected to an outer wire stopper provided on the bracket that supports the second brake. The first brake wire fixed to the one end and one end of the inner wire are provided on the operation lever of the second brake. An outer wire stopper that is fixed to a bracket that supports the second brake via an outer wire holder that holds one end of the outer wire, and the other end of the inner wire is provided on the bracket that supports the first brake. And a second brake wire fixed to the outer wire holder via the tool.
According to the brake for a wheelchair of the present invention, the first brake and the second brake provided on the left and right wheels of the wheelchair are connected by the power transmission mechanism configured as described above. When the outer wire holding member moves to the second brake side along the inner wire in accordance with the brake operation, the second brake is pulled toward the first brake side, so that the second brake is also operated at the same time. When the second brake is operated, the first brake is also operated simultaneously.
As a result, the left and right wheels can be braked at the same time by braking either one of the first brake and the second brake provided on the left and right wheels of the wheelchair.

  According to the wheelchair brake of the present invention, a wheelchair user can perform a brake operation with a smaller force than before. Accordingly, it is possible to provide a wheelchair brake that is suitable particularly when the wheelchair is a resin tire having a hard property or when the brake operation is simultaneously performed on both the left and right tires of the wheelchair.

  Moreover, according to the brake for a wheelchair of the present invention, the brake is applied to both the left and right wheels at the same time by operating either the first brake or the second brake provided on the left and right wheels of the wheelchair. Can do.

Perspective view showing the whole wheelchair Explanatory drawing explaining the brake of the 1st Embodiment of this invention A diagram of a pair of brakes on the left and right of a wheelchair connected by a power transmission mechanism The figure which brakes a pair of brakes provided on the left and right of the wheelchair at a time The figure explaining the operation mechanism of the brake of the conventional product Diagram of the brake release state, contact state, and brake state in the brake operating mechanism of the invention Explanatory drawing explaining the difference of the stroke of the control lever and tire pressing member of a conventional product and an invention product Explanatory drawing of output angle with respect to input angle in conventional product and invention product Explanatory drawing explaining the difference between the input angle and the output angle between the conventional product and the invention product Explanatory drawing before brake operation with the brake of the 2nd Embodiment of this invention Explanatory drawing at the time of brake termination in the brake of the second embodiment of the present invention

  A preferred embodiment of a wheelchair brake according to the present invention will be described below in detail with reference to the accompanying drawings.

[First embodiment]
FIG. 1 is a perspective view showing the entire wheelchair 10 according to the first embodiment of the present invention.
As shown in FIG. 1, a wheelchair 10 according to the present embodiment is formed with a chair-like body frame 12 that forms a framework structure of the wheelchair 10 by a plurality of pipe pipes. A pair of left and right rear wheels 14 and 14 are provided at the rear portion of the main body frame 12, and a pair of left and right front wheels 16 and 16 are provided at the front portion of the main body frame 12.

  The rear wheel 14 is rotatably supported by the main body frame 12 by fitting an axle shaft 14B provided at the center of the wheel 14A into an axle support hole 12A attached to the main body frame 12. The axle support hole 12A is formed such that the axle shaft 14B can be detachably attached, and a plurality of axle support holes 12A are provided in the longitudinal direction. Thereby, it can respond to the wheel from which a diameter (number of inches) differs. And the tire 18 of either a rubber tire or a resin tire is provided in the outer periphery of the wheel 14A.

  The front wheel 16 is formed in a caster structure. That is, a yoke 16B that rotatably supports a wheel 16A smaller than the rear wheel 14 is provided, and a shaft of the yoke 16B is fitted into a cylindrical support tube 12B provided on the main body frame 12. Thus, the front wheel 16 can turn in the entire circumferential direction on a horizontal plane. The tire 20 provided on the outer periphery of the front wheel 16 may be a rubber tire or a resin tire.

  Further, the main body frame 12 is provided with a backrest, an armrest, a seat, a footrest for placing a foot, etc., but only the armrests 22 and 22 and the footrest 24 are illustrated in FIG. 1, and the backrest and the seat are not illustrated. .

  Brackets 26 and 26 (see also FIG. 3) are provided in the vicinity of the left and right rear wheels 14 and 14 of the main body frame 12, and brakes 28 and 28 for braking the rear wheel 14 are attached to the bracket 26, respectively. .

Next, details of the brake 28 will be described with reference to FIG.
As shown in FIG. 2, the brake 28 mainly includes an operation lever 30, a tire pressing member 32, a connecting arm 34, a rotating body 36, an engagement portion 38 formed on the operation lever 30, and an urging unit. 40.

  The operation lever 30 is rotatably supported by the bracket 26 via the first pin 42. The operation lever 30 includes a grip portion 30A that is gripped by a user's hand and a long plate-shaped operation portion 30B, and a first pin 42 is disposed on the distal end side of the operation portion 30B. A curved engagement portion 38, which will be described in detail later, is formed on the side surface in the tire 18 direction on the distal end side of the operation portion 30B where the first pin 42 is disposed. Further, when the operating lever 30 is rotated in the brake operation direction, a curved notch is formed at the contact portion where the side surface of the operation portion 30B comes into contact with the proximal end portion of the tire pressing member 32 and the brake operation is finished. A portion 39 is formed.

  The tire pressing member 32 has a pressing portion 32 </ b> A that presses the tire 18 at the distal end portion, and a base end portion is rotatably supported by the bracket 26 via the second pin 44. The tire pressing member 32 is formed in an L shape with its tip end bent at a right angle, and the bent portion constitutes the pressing portion 32A. As a result, the pressing portion 32 </ b> A contacts the tire 18 horizontally.

  The connecting arm 34 includes a first arm 34 </ b> A, one end of which is rotatably supported by the bracket 26 via a third pin 46, and one end which is rotated via a fourth pin 48 to the tip end side of the tire pressing member 32. The second arm 34B is supported freely and has the other end pivotally connected to the other end of the first arm 34A via a fifth pin 50. The position of the fourth pin 48 is preferably provided in the vicinity of the pressing portion 32A slightly before the tire pressing member 32 bends at a right angle.

  By configuring the connecting arm 34 in this way, as can be seen from FIG. 2, when the position of the fifth pin 50 is changed (moved) downward, the posture of the second arm 34B changes from the oblique direction to the horizontal direction. The tire pressing member 32 rotates counterclockwise about the second pin 44 as it changes. Accordingly, the pressing portion 32A of the tire pressing member 32 abuts on the tire 18 and is pressed into the tire 18, so that the rear wheel 14 can be braked.

  A rotating body 36 is rotatably supported on the fifth pin 50, and the rotating body 36 engages with the engaging portion 38 of the operation lever 30. Accordingly, when the operating lever 30 is rotated to change the position of the fifth pin 50 of the connecting arm 34, the rotating body 36 that engages with the engaging portion 38 rotates, so that the position of the fifth pin 50 can be smoothly moved. Can be changed.

  Further, the first arm 34A of the connecting arm 34 is preferably formed in a curved shape. When the position of the fifth pin 50 of the connecting arm 34 is changed in order to separate the pressing portion 32A of the tire pressing member 32 from the tire 18, the first arm 34A swings around the third pin 46 accordingly. Perform the action. Therefore, if the first arm 34A has a straight bar shape, the first arm 34A hits the first pin 42, and the position change of the second pin 50 is obstructed. Accordingly, the stroke of the operation lever 30 is reduced, and it is difficult to reliably push the pressing portion 32A of the tire pressing member 32 into the tire 18.

  However, by forming the first arm 34A in a curved shape, the first arm 34A can be prevented from hitting the first pin 42, so that a large stroke of the operation lever 30 can be secured.

  The urging means 40 may be any means that urges the pressing portion 32A of the tire pressing member 32 in the direction away from the tire 18, that is, the direction in which the V-shape formed by the second arm 34B and the tire pressing member 32 is closed. Any type can be used, but, for example, a mainspring spring or a coil spring wound around the second pin 44 can be preferably used.

As can be seen from the relationship between the operation lever 30, the tire pressing member 32, and the connecting arm 34 described above, the wheelchair brake 28 of the present embodiment has the operation of the operation lever 30 and the operation of the tire pressing member 32. It has an independent structure. Then, the engaging portion 38 of the operating lever 30 and the rotating body 36 provided on the fifth pin 50 of the connecting arm 34 are engaged so that the power from the operating lever 30 is transmitted to the tire pressing member 32. It has become.
Further, the shape of the engaging portion 38 formed on the operation lever 30 is such that the distance from the force point X of the lever that the user holds the operation lever 30 to the center of the first pin 42 that becomes the fulcrum P of the lever is A. When the distance from the fulcrum to the center of the rotating body 36 (synonymous with the center of the fifth pin 50) serving as the lever operating point Q is B, the lever ratio is increased as the operating lever 30 is rotated in the brake operating direction. B / A is formed to be small. The insulator ratio B / A will be described in detail with reference to FIG.

In the present invention, the distance from the fulcrum P of the lever to the center of the rotating body 36 serving as the point of action Q of the lever is B, but the contact point where the engaging portion 38 of the operating lever 30 and the rotating body 36 come into contact with each other. The same applies when Q ₁ is the point of action and the distance from the fulcrum P of the insulator to the contact point Q ₁ is B.

  Although not shown, a curved elongated hole may be formed in the distal end portion of the operation lever 30 as another aspect of the engaging portion 38 of the operation lever 30. Even when the engaging portion 38 is a curved long hole, the shape of the long hole is formed such that the lever ratio B / A decreases as the operation lever 30 is rotated in the brake operation direction.

  3 and FIG. 4, a pair of brakes 28, 28 provided on the left and right sides of the wheelchair 10 are connected by a power transmission mechanism 52, and the left and right rear wheels 14, 14 is configured to be able to brake at once. In FIG. 3, one rear wheel 14 of the left and right rear wheels 14 and 14 is omitted in order to make it easy to see the connection state between the brake 28 and the power transmission mechanism 52.

  As shown in FIGS. 3 and 4, the power transmission mechanism 52 is configured by connecting two brake wires 54, 54 to a pair of brakes 28 provided on the left and right sides of the wheelchair 10. One of the pair of brakes 28 is a first brake 28A, and the other is a second brake 28B. 4 is a diagram in which a pair of left and right brakes 28A and 28B for braking a pair of rear wheels 14 and 14 provided on the left and right sides of the wheelchair 10 are connected by two brake wires 54 and 54. The middle of the brake wires 54, 54 is omitted.

  The brake wire 54 includes an inner wire 56 formed of a steel wire such as a piano wire, and an outer wire 58 that is an outer peripheral cover of the inner wire 56. One end of the inner wire 56 of the first brake wire 54 is provided at a substantially central portion of the operation lever of the first brake 28A, and the first brake is interposed via an outer wire holder 60 that holds one end of the outer wire 58. The bracket 26 that supports 28A is fixed by a fixing bolt 62. The other end of the inner wire 56 is fixed to the outer wire holder 60 via an outer wire stopper 64 provided on the bracket 26 that supports the second brake 28B.

  Similarly, one end of the inner wire 56 of the second brake wire 54 is provided at the substantially central portion of the operation lever of the second brake 28B, and the second wire is interposed via the outer wire holder 60 that holds one end of the outer wire 58. The bracket 26 that supports the brake 28B is fixed by a fixing bolt 62. The other end of the inner wire 56 is fixed to the outer wire holder 60 via an outer wire stopper 64 provided on the bracket 26 that supports the first brake 28A.

That is, the two brake wires 54 and 54 are connected so as to be in contrast to the pair of brakes 28A and 28B.
Accordingly, as shown in FIGS. 4A and 4B, for example, the outer wire holding member 60 moves along the inner wire 56 toward the second brake 28B along with the brake operation of the operation lever 30 of the first brake 28A. By moving, the second brake 28B is pulled to the first brake side. The same applies when the operating lever 30 of the second brake 28B is braked. Thus, the brake can be applied to the pair of rear wheels 14 and 14 by operating the operating lever 30 of either the first brake 28A or the second brake 28B.

  Next, the operation mechanism of the wheelchair brake 28 of the present invention configured as described above will be described in comparison with the conventional example. FIG. 5 shows a conventional wheelchair brake 66, and FIG. 6 shows an inventive brake 28 according to the present embodiment. In the conventional wheelchair brake 66, the same members as those of the invention will be described with the same reference numerals.

  As shown in FIG. 5, the conventional brake 66 is formed in a link mechanism in which the distal end portion of the operation lever 30 and the distal end portion of the tire pressing member 32 are connected by an arm 70 via a pin 68. That is, it differs from the wheelchair brake of the present invention in that the operation of the operation lever and the operation of the tire pressing member are not independently separated.

  With reference to FIG. 5, the operation mechanism of a conventional wheelchair brake will be described. The user grasps the position of the force point X of the operation lever 30 and rotates the operation lever 30 in the arrow direction. As a result, the posture of the arm 70 changes from the oblique direction to the horizontal direction, and the tire pressing member 32 rotates counterclockwise about the second pin 44. Thereby, the pressing portion 32A of the tire pressing member 32 abuts on the tire 18, and the pressing portion 32A is pushed into the tire 18 by further rotating the operation lever 30. As a result, the rear wheel 14 can be braked.

  In such a brake operation, in the conventional wheelchair brake 66, the lever ratio B / A is always constant from the start of the brake operation until the pressing portion 32A is pushed into the tire 18 and the brake operation is finished.

  Next, an operation mechanism of the wheelchair brake 28 according to the present embodiment will be described with reference to FIGS. 6A to 6C.

FIG. 6A is a diagram before the brake process is performed by the operation lever 30, and the rotating body 36 of the connection arm 34 is engaged with the upper portion of the curved engagement portion 38 of the operation lever 30. In this case, the rotating body 36 is pressed against the engaging portion 38 by the urging force of the urging means 40 that urges the pressing portion 32 </ b> A in the direction away from the tire 18, and the engagement between the engaging portion 38 and the rotating body 36. There will be no mistakes. The insulator ratio at this time is B ₁ / A.

Next, in FIG. 6A, the operation lever 30 is rotated in the direction of the arrow to perform a brake operation. As a result, as shown in FIG. 6B, the curved engaging portion 38 of the operation lever 30 pushes down the rotating body 36, so that the rotating body 36 moves downward following the shape of the engaging portion 38. Accordingly, the posture of the second arm 34B changes from the oblique direction to the horizontal direction, and the tire pressing member 32 rotates counterclockwise about the second pin 44. Thereby, the pressing portion 32 </ b> A of the tire pressing member 32 comes into contact with the tire 18. The insulator ratio at this time is set to B ₂ / A.

Next, in FIG. 6B, the operation lever 30 is further rotated in the arrow direction.
By further rotating the operation lever 30, as shown in FIG. 6C, the curved engagement portion 38 of the operation lever 30 further pushes down the rotation body 36. It moves further downward following the shape. Accordingly, the posture of the second arm 34B is further changed from the oblique direction to the horizontal direction, and the tire pressing member 32 is further rotated counterclockwise around the second pin 44. Accordingly, the pressing portion 32A of the tire pressing member 32 is pushed into the tire 18, so that the rear wheel 14 can be braked. The insulator ratio at this time is set to B ₃ / A.

As can be seen from the insulator ratios in FIGS. 6A to 6C, A is always constant, but B decreases in the order of B ₁ , B ₂ , and B ₃ . That is, the wheelchair brake 28 of the present embodiment is formed so that the lever ratio B / A becomes smaller as the operation lever 30 is rotated in the brake operation direction. This means that the brake operation can be performed with a small force as the brake operation by the operation lever 30 approaches from the start to the end.

  Accordingly, the lever ratio B / A is further reduced when the pressing portion 32A of the tire pressing member 32 that requires the greatest force in the brake operation is pressed against the tire 18 and then pressed. Therefore, the user can perform the brake operation with a smaller force than before. In particular, even if the wheelchair 10 is a resin tire harder than a rubber tire, the brake operation can be performed with a small force.

  Next, a specific example in which the difference between the strokes of the operation lever 30 and the tire pressing member 32 from the start to the end of the brake operation in the conventional brake 66 and the inventive brake 28 will be described.

  FIG. 7A shows a state in which the brake is released (hereinafter referred to as “brake release”). FIG. 7B shows a state in which the pressing portion 32A of the tire pressing member 32 is in contact with the tire 18 (hereinafter referred to as “contact”). FIG. 7C is a diagram showing that the pressing portion 32A is being pushed into the tire 18 (hereinafter referred to as “braking”).

  In addition, an angle formed by a stroke in which the operation lever 30 rotates is referred to as an input angle, and an angle of a stroke in which the tire pressing member 32 rotates in accordance with the stroke of the operation lever 30 is referred to as an output angle.

  FIG. 8 is a graph of specific numerical values and graphs used for obtaining the input angle and output angle from the release of the brake to the contact and the input angle and output angle from the contact to the brake in FIG. is there.

  First, from a conventional wheelchair brake 66, the operation lever 30 is rotated in the direction of the arrow from the release of the brake shown in FIG. Thereby, as shown in FIG. 7B, the pressing portion 32 </ b> A of the tire pressing member 32 comes into contact with the tire 18. At this time, the input angle is 15.5 ° and the output angle is 14.2 °.

  The operation lever 30 in FIG. 7B is further rotated in the direction of the arrow, and the pressing portion 32A of the tire pressing member 32 is pushed into the tire 18 as shown in FIG. 7C. As a result, braking is in progress. At this time, the input angle is 34.5 ° and the output angle is 5.8 °.

  In other words, in the conventional wheelchair brake 66, the entire input angle of the operation lever 30 from the start to the end of the brake operation is 50 ° (15.5 ° + 34.5 °). The output angle is 20 ° (14.2 ° + 5.8 °).

  Next, the wheelchair brake 28 according to the invention will be described. The operating lever 30 is rotated in the direction of the arrow from the brake released state of FIG. Thereby, as shown in FIG. 7B, the pressing portion 32 </ b> A of the tire pressing member 32 comes into contact with the tire 18. The input angle at this time is 7.0 °, and the output angle is 9.5 °.

  The operation lever 30 in FIG. 7B is further rotated in the direction of the arrow, and the pressing portion 32A of the tire pressing member 32 is pushed into the tire 18 as shown in FIG. 7C. As a result, braking is in progress. At this time, the input angle is 55.0 ° and the output angle is 11.0 °.

  That is, the brake 28 for the wheelchair of the invention has a total input angle of 62 ° (7.0 ° + 55.0 °) from the start to the end of the brake operation. The output angle is 20.5 ° (9.5 ° + 11.0 °).

  Here, in order to compare the difference in stroke between the invention product and the conventional product on the same basis, the input angle from the brake release to the contact and the input angle from the contact to the brake are shown as a percentage of the total input angle. . Similarly, the output angle from the release of the brake to the contact and the output angle from the contact to the brake are expressed as a percentage of the total output angle. The result is shown in FIG.

  As can be seen from the table of FIG. 9, in the case of the brake 66 of the conventional product, the input angle from the brake release to the contact is 31% of the total input angle, whereas in the case of the brake 28 of the invention product. Is 11%. The output angle of the brake 66 of the conventional product at that time is 71% of the total output angle, whereas it is 46% in the case of the brake 28 of the invention.

  In the case of the conventional brake 66, the input angle from contact to braking is 69% of the total input angle, whereas in the case of the inventive brake 28, it is 89%. The output angle of the conventional product at that time is 29% of the total output angle, while that of the invention product is 54%.

  That is, the brake 28 of the invention can obtain a large output angle with a small input angle in the operation from the release of the brake to the contact as compared with the brake 66 of the conventional product. Further, in the operation from contact to braking, the brake 28 of the invention can make the ratio of the output angle to the input angle smaller than the brake 66 of the conventional product. In particular, when attention is paid to the output angle from contact to braking during braking, the conventional product can use only about 30% of the total output angle, while the invention product can use about 50%. . This means that the brake 28 of the invention can increase the amount of pressing the tire 18 is pushed by the pressing portion 32A of the tire pressing member 32 compared to the brake 66 of the conventional product.

  Strictly speaking, the tire 18 is not a perfect circle but is slightly distorted, so that the amount of pressing the pressing portion 32A pushes the tire 18 varies depending on the position of rotation of the rear wheel 14, and the braking performance (the degree of braking effectiveness) varies.

  However, in the case of the brake 28 of the invention, even if the tire 18 is somewhat distorted, the pushing amount of the pressing portion 32A into the tire 18 is large, so that the rear wheel 14 can be reliably braked. In this case, even if the pushing amount for pushing the pressing portion 32A into the tire 18 is increased, the lever ratio B / A at the time of pushing in is small as described above, so that the burden on the user is not increased.

Even when the tires 18 of the left and right rear wheels 14 and 14 are braked at a time, the lever ratio B / A at the time of pushing in is small, so that the burden on the user is not increased.
In consideration of the relationship with the insulator ratio B / A, the ratio of the output angle from the contact to the brake during the total output angle is preferably in the range of 40% to 60%.

[Second Embodiment]
FIG. 10 is an explanatory view of a wheelchair brake according to the second embodiment of the present invention.
The brake 72 for a wheelchair according to the second embodiment is different from the first embodiment in the brake structure, and the other parts are the same as those in the first embodiment. Therefore, the overall configuration of the wheelchair 10 and the wheelchair 10 are the same. The description of the power transmission mechanism 52 that transmits brake power to the pair of brakes 72, 72 provided on the left and right sides of the brake is omitted. The same members as those in the first embodiment will be described with the same reference numerals.

  As shown in FIG. 10, the brake 72 is mainly provided at the operation lever 30, the tire pressing member 32, the long hole 73 formed in the tire pressing member 32, and the distal end portion of the operating lever 30. And an engaging pin 74 that engages with.

  The operation lever 30 is rotatably supported by the bracket 26 via the first pin 76. The operation lever 30 includes a grip portion 30A that is gripped by a user's hand and an operation portion 30B formed in a substantially right triangle shape. The first pin 76 is arranged at a right angle portion of the operation portion 30B formed in a substantially right triangle shape, and the grip portion 30A is fixed to one corner portion sandwiching the right angle portion by the fastening pin 77, and the other corner portion. The engagement pin 74 is fixed in a direction orthogonal to the operation unit 30B (at the tip of the operation lever 30). Further, the side portion on the tire 18 side of the operation portion 30B is recessed in a curved shape, so that the operation portion 30B does not hit a second pin 78 of a tire pressing member 32 described later during a brake operation. .

  The tire pressing member 32 has a pressing portion 32 </ b> A that presses the tire 18 at the distal end portion, and a base end portion is rotatably supported by the bracket 26 via a second pin 78. The tire pressing member 32 is formed in an L shape with its tip end bent at a right angle, and the bent portion constitutes the pressing portion 32A. As a result, the pressing portion 32 </ b> A comes into contact with the tire 18 substantially horizontally.

  Moreover, it is preferable that the tire pressing member 32 is formed in a dogleg shape in which the tire 18 side is recessed. As a result, when the brake operation is started, the pressing portion 32A of the tire pressing member 32 can be brought into contact with the tire 18 with a smaller rotation of the operation lever 30.

  The engagement pin 74 is provided in a state of being engaged with the elongated hole 73 at the distal end portion of the operation lever 30, and the engagement position with respect to the elongated hole 73 is changed by rotating the operation lever 30 to press the tire pressing member 32. The part 32 </ b> A is separated from the tire 18.

  It is preferable to provide an urging means 40 that urges the pressing portion 32 </ b> A of the tire pressing member 32 in a direction away from the tire 18. Accordingly, the tire pressing member 32 can be easily separated from the tire 18 when the brake is released, and rattling of the engaging pin 74 in the elongated hole 73 can be prevented. As the biasing means, for example, a mainspring spring or a coil spring wound around the second pin 78 can be suitably used.

  As can be seen from the relationship between the operation lever 30, the tire pressing member 32, the long hole 73, and the engagement pin 74 described above, the wheelchair brake 72 according to the present embodiment has the operation of the operation lever 30 and the tire pressing force. The operation of the member 32 is independently separated. Then, the engagement pin 74 of the operation lever 30 and the elongated hole 73 of the tire pressing member 32 are engaged, whereby the force from the operation lever 30 is transmitted to the tire pressing member 32.

  In addition, the long hole 73 formed in the tire pressing member 32 indicates a distance from the center of the second pin 78 serving as a fulcrum P of the lever in the tire pressing member 32 to the action point Q of the pressing portion 32A that presses the tire 18 a. When the distance from the fulcrum P of the lever to the center of the engaging pin 74 of the operation lever 30 that becomes the force point X of the lever is b, the lever ratio b / is increased as the operation lever 30 is rotated in the brake operation direction. It is formed so that a becomes large.

  As described above, the wheelchair brake 28 according to the first embodiment described above is a case where the lever mechanism arranged in the order of the action point Q, the fulcrum P, and the force point X is used for the brake structure. The brake 72 for a wheelchair of the embodiment uses a lever mechanism arranged in the order of the action point Q, the force point X, and the fulcrum P in the brake structure. In the second embodiment, the operation lever 30 that is another lever is used for brake operation at the force point X of the tire pressing member 32 of the lever mechanism arranged in the order of the action point Q, the force point X, and the fulcrum P. The power of was added.

Next, the operation mechanism of the wheelchair brake 72 according to the second embodiment will be described with reference to FIGS. 10 and 11.
FIG. 10 is a view before the brake processing is performed by the operation lever 30, and the engagement pin 74 of the operation lever 30 is engaged with the upper portion of the elongated hole 73 of the tire pressing member 32. The insulator ratio at this time is b ₁ / a.

Next, the brake operation is performed by rotating the operation lever 30 in the direction of the arrow in FIG. As a result, as shown in FIG. 11, the engaging pin 74 of the operation lever 30 pushes the tire pressing member 32 toward the tire 18 while moving to the lower portion of the long hole 73 of the tire pressing member 32. Accordingly, the tire pressing member 32 rotates counterclockwise about the second pin 78. Thereby, after the pressing portion 32A of the tire pressing member 32 abuts on the tire 18, it is pushed into the tire 18, so that the rear wheel 14 can be braked. The insulator ratio at this time is b ₂ / a.

As can be seen from the lever ratios in FIGS. 10 to 11, a is always constant, but b increases in the order of b ₁ and b ₂ . That is, the wheelchair brake 72 of the present embodiment is formed so that the lever ratio b / a increases as the operation lever 30 is rotated in the brake operation direction. This means that the brake operation can be performed with a small force as the brake operation by the operation lever 30 approaches from the start to the end.

  That is, according to the wheelchair brake 72 of the second embodiment, the engaging pin 74 provided at the tip of the operating lever 30 that rotates about the first pin 76 and the second pin 78 are the center. The lever ratio b / a is increased as the elongated lever 73 formed in the rotating tire pressing member 32 is engaged and the operation lever 30 is rotated in the brake operation direction.

  Thus, when the operation lever 30 is rotated in the brake operation direction, the engagement pin 74 that is the lever power point X of the tire pressing member 32 is guided by the elongated hole 73 of the tire pressing member 32 and the tire pressing member 32. The fulcrum P (second pin 78) gradually approaches the action point Q (pressing portion 32A).

  That is, at the brake operation start stage of the operation lever 30, the distance from the fulcrum P to the force point X is small, and the distance from the force point X to the action point Q is large. As a result, a large motion (output angle) can be generated at the action point Q by a small motion (input angle) applied to the force point X, so that the pressing portion 32A of the tire pressing member 32 can be moved by a small rotation of the operation lever 30. It can be brought into contact with the tire 18.

  Then, as the brake operation ends, the distance from the fulcrum P to the force point X of the tire pressing member 32 gradually increases, and the distance from the force point X to the action point Q gradually decreases. As a result, the force applied to the force point X is largely transmitted to the action point Q. Therefore, even if the operation lever 30 is operated with the same force as in the brake operation start stage, the force at the action point Q is larger than that in the brake operation start stage. Can act. That is, the brake operation can be performed with a small force as the brake operation by the operation lever 30 approaches from the start to the end.

  Thus, the lever ratio b / a is further increased when the pressing portion 32A of the tire pressing member 32 that requires the greatest force in the brake operation is pressed against the tire 18 and then pressed. Therefore, the user can perform the brake operation with a smaller force than before.

  In addition, since the pressing portion 32A of the tire pressing member 32 can be brought into contact with the tire 18 by a small rotation of the operation lever 30 at the stage of starting the brake operation, the pressing portion 32A is in contact with the tire 18 until it is pushed in. A large rotation of the operation lever 30 can be ensured. As a result, the tire 18 can be reliably braked.

  Therefore, even in the case of the wheelchair brake 72 of the second embodiment, the user can perform the brake operation with a smaller force than before. In particular, even when the wheelchair 10 is a resin tire harder than a rubber tire or when the brake operation is simultaneously performed on both the left and right tires 18 of the wheelchair, the brake operation can be performed with a small force.

DESCRIPTION OF SYMBOLS 10 ... Wheelchair, 12 ... Body frame, 14 ... Rear wheel, 16 ... Front wheel, 18 ... Rear wheel tire, 20 ... Front wheel tire, 22 ... Armrest, 24 ... Footrest, 26 ... Bracket, 28 ... Brake (first (Embodiment), 30 ... control lever, 32 ... tire pressing member, 34 ... connecting arm, 36 ... rotating body, 38 ... engaging portion, 39 ... notch, 40 ... biasing means, 42 ... first pin, 44 ... 2nd pin, 46 ... 3rd pin, 48 ... 4th pin, 50 ... 5th pin, 52 ... Power transmission mechanism, 54 ... Brake wire, 56 ... Inner wire, 58 ... Outer wire, 60 ... Outer wire 62, fixing bolt, 64 ... outer wire stopper, 66 ... conventional brake, 68 ... pin, 70 ... arm, 72 ... brake (second embodiment), 73 ... long hole, 74 ... engagement Pin, 76 The first pin, 77 ... fastening pin, 78 ... the second pin, P ... fulcrum, Q ... the point of action, X ... emphasis

Claims (11)

In wheelchair brakes that brake wheelchair tires,
An operation lever rotatably supported by a bracket provided on a body frame of the wheelchair via a first pin;
A tire pressing member having a pressing portion that presses the tire at a distal end portion, and a base end portion is rotatably supported by the bracket via a second pin;
A first arm having one end rotatably supported on the bracket via a third pin, and one end rotatably supported on the tip end side of the tire pressing member via a fourth pin and the other end Is composed of a second arm rotatably connected to the other end of the first arm via a fifth pin, and the pressing portion of the tire pressing member is moved against the tire by changing the position of the fifth pin. Connecting arms that are separated from each other,
A rotating body rotatably supported by the fifth pin;
An engaging portion that is formed at a distal end portion of the operation lever and engages the rotating body and changes the position of the fifth pin by moving the rotating body according to an engagement shape;
Urging means for urging the pressing portion of the tire pressing member in a direction away from the tire,
The shape of the engaging portion is such that the distance from the force point of the lever that grips the operation lever to the center of the first pin that is the fulcrum of the lever is A, and the rotating body that is the point of action of the lever from the fulcrum of the lever A wheelchair brake characterized in that when the distance to the center is B, the lever ratio B / A is reduced as the operating lever is rotated in the brake operating direction.   The rate at which the lever ratio B / A decreases as the operating lever is rotated in the brake operating direction is such that the pressed portion of the tire pressing member is in contact with the tire rather than the pressed portion of the tire pressing member is in contact with the tire. The brake for a wheelchair according to claim 1, wherein the brake for the wheelchair is larger when pushed into the tire.   When the angle of the stroke for rotating the operation lever in the brake operation direction is an input angle, and the stroke of the tire pressing member that rotates with the rotation of the operation lever is an output angle, the tire pressing member is pressed. The wheelchair according to claim 1 or 2, wherein an output angle from when the portion abuts on the tire to when the brake operation is finished after being pushed into the tire is 40% to 60% of a total output angle of the tire pressing member. brake.   The wheelchair brake according to any one of claims 1 to 3, wherein the engaging portion is a curved concave portion that is concavely cut out at a distal end portion of the operation lever.   The wheelchair brake according to any one of claims 1 to 3, wherein the engagement portion is a curved long hole formed at a tip portion of the operation lever.   When the operation lever is rotated in the brake operation direction, the side surface of the operation lever comes into contact with the base end portion of the tire pressing member, so that the brake operation is finished and the contact portion of the operation lever is curved. The brake for wheelchairs of any one of Claims 1-5 in which the notch part of this is formed.   The wheelchair brake according to any one of claims 1 to 6, wherein the first arm is formed in a curved shape. In wheelchair brakes that brake wheelchair tires,
An operation lever rotatably supported by a bracket provided on a body frame of the wheelchair via a first pin;
A tire pressing member having a pressing portion that presses the tire at a distal end portion, and a base end portion is rotatably supported by the bracket via a second pin;
An elongated hole formed in the tire pressing member;
Provided at the tip of the operation lever in a state of being engaged with the elongated hole, and by rotating the operation lever to change the engagement position with respect to the elongated hole, the pressing portion of the tire pressing member is moved against the tire. And an engaging pin to be separated
The long hole is a distance from the center of the second pin serving as a fulcrum of the lever in the tire pressing member to the point of action of the pressing portion that presses the tire, and is a force point of the lever from the fulcrum of the lever. The lever ratio b / a is increased as the operation lever is rotated in the brake operation direction, where b is the distance to the center of the engagement pin of the operation lever. Brakes for wheelchairs.   The wheelchair brake according to claim 8, wherein the tire pressing member is formed in a dogleg shape in which the tire side is recessed.   The brake for a wheelchair according to any one of claims 1 to 9, wherein the brake is provided on each of the left and right wheels of the wheelchair, and each brake is connected by a power transmission mechanism. A wheelchair brake having a power transmission mechanism that applies brakes to both the left and right wheels at the same time by operating one of the first brake and the second brake provided on the left and right wheels of the wheelchair,
The power transmission mechanism is
One end of the inner wire is fixed to a bracket that supports the first brake via an outer wire holder that is provided on the operation lever of the first brake and holds one end of the outer wire. A first brake wire having an end fixed to an outer wire holder via an outer wire stopper provided on a bracket supporting the second brake;
One end of the inner wire is fixed to a bracket that supports the second brake via an outer wire holder that is provided on the operation lever of the second brake and holds one end of the outer wire. And a second brake wire fixed to the outer wire holder via an outer wire stopper provided on a bracket that supports the first brake. brake.

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