Patent Application
20050252333
The present invention relates to a man-powered braking apparatus with which the base part of a braking lever is rockably pivoted to a base fixed to a car body; the end part of the braking lever is extended to the vicinity of the operator; and brake is applied by exerting a force on the end part thereof for pulling a braking cable in accordance with turning of the braking lever.
For example, as a man-powered braking apparatus, such as a treadle-powered type parking brake, a system with which the base part of a braking lever is rockably pivoted to a base fixed to a car body; the end part of the braking lever is extended to the vicinity of the operator; and brake is applied by exerting a force on the end part thereof for pulling a braking cable in accordance with turning of the braking lever is known.
As such a conventional man-powered braking apparatus, that as disclosed in Japanese Laid-Open Publication No. 7-186909.
In Japanese Laid-Open Publication No. 7-186909, the art wherein a lock mechanism of internal tooth ratchet type which holds the braking link in the braking state when the braking lever is treaded from the non-braking state, and then released, and releases the brake holding state when the braking lever is again treaded, and a sliding plate is used for releasing the brake holding state.
However, with such a prior art, the sliding plate is displaced to switch over between the braking state and the releasing state, which results in a high sliding resistance, and use of the sliding displacement makes it difficult to reduce the amount of displacement, which involves a proportionately great reduction in braking force.
Being developed in consideration of such problems of the prior art, the purpose of the present invention is to provide a man-powered braking apparatus which uses rocking motion to switch over between the braking state and the releasing state, assures smooth operation, and minimizes the reduction in braking force when the braking lever is returned.
The subject matters of the present invention to achieve the above purpose are disclosed in the following items:
[1] A man-powered braking apparatus (1) with which the base part (21) of a braking lever (20) is rockably pivoted to a base (10) fixed to a car body; the end part (23) of the braking lever (20) is extended to the vicinity of the operator; and brake is applied by exerting a force on the end part (23) thereof for pulling a braking cable (C) in accordance with turning of the braking lever (20), wherein
an output link member (30) to which the braking cable (C) is connected is pivoted to said base (10) coaxially with said braking lever (20); a pawl member (40) which is engaged with teeth (12a) of a ratchet plate (12) fixedly installed to said base (10) to maintain the braking state is pivoted to the output link member (30); a transmission link member (50) is disposed between said braking lever (20) and said output link member (30);
said output link member (30) is pushed by the base part (21) of said braking lever (20) through said transmission link member (50), being turned in one direction from the non-braking position to pull the braking cable (C) connected to the output link member (30) for generation of a braking force;
said transmission link member (50) is pivoted to said output link member (30) such that it is capable of being rocked between the braking position and the releasing position, and has a cam groove (52) which is fitted with a power transmission pin (25) fixedly installed to the base part (21) of said braking lever (20);
said pawl member (40) is capable of being kept energized by a turnover spring (45) disposed between it and said transmission link member (50) in the direction for being engaged with or disengaged from the teeth (12a) of said ratchet plate (12);
the cam groove (52) in said transmission link member (50) has a force transmission cam groove (53) which is formed such that, when the transmission link member (50) is in the braking position, the force which is applied to the end part (23) of said braking lever (20) can be transmitted to said output link member (30), and a release holding cam groove (54) which, when the force applied to said braking lever (20) is removed, and the braking lever (20) is returned by a return spring (26), causes said transmission link member (50) to be turned to the releasing position, and said turnover spring (45), which has energized said pawl member (40) in the direction for being engaged with the teeth (12a) of said ratchet plate (12), to be inverted such that said pawl member (40) is energized in the direction for being disengaged from the teeth (12a) of said ratchet plate (12);
when a force is applied to the end part (23) of said braking lever (20) for pulling the braking cable (C) in accordance with turning of the braking lever (20) to operate the brake, and then the force is removed, the pawl member (40) engages with the teeth (12a) of the ratchet plate (12) to maintain the braking state; when the braking lever (20) is displaced in the returning direction by the return spring (26), the pawl member (40) is brought into the state in which it is energized in the direction for being disengaged from the teeth (12a) of said ratchet plate (12) while the braking state being maintained; then, when a force is once applied to the braking lever (20) for releasing the brake, the pawl member (40) is disengaged from the teeth (12a) of said ratchet plate (12); and then when the force is removed, the braking lever (20) and said output link member (30) are turned in the brake releasing direction for releasing the brake.
[2] A man-powered braking apparatus (1) with which the base part (21) of a braking lever (20) is rockably pivoted to a base (10) fixed to a car body; the end part (23) of the braking lever (20) is extended to the vicinity of the operator; and brake is applied by exerting a force on the end part (23) thereof for pulling a braking cable (C) in accordance with turning of the braking lever (20), wherein
an output link member (30) to which the braking cable (C) is connected is pivoted to said base (10) coaxially with said braking lever (20); a pawl member (40) which is engaged with teeth (12a) of a ratchet plate (12) fixedly installed to said base (10) to maintain the braking state is pivoted to the output link member (30); a transmission link member (50) disposed between said braking lever (20) and said output link member (30) is pivoted to the output link member (30) coaxially with the pawl member (40);
said output link member (30) is pushed by the base part (21) of said braking lever (20) through said transmission link member (50), being turned in one direction from the non-braking position to pull the braking cable (C) connected to the output link member (30), being wound thereon, for generation of a braking force;
said transmission link member (50) is pivoted to said output link member (30) such that it is capable of being rocked between the braking position and the releasing position, and has a cam groove (52) which is fitted with a power transmission pin (25) fixedly installed to the base part (21) of said braking lever (20);
said pawl member (40) is capable of being kept energized by a turnover spring (45) disposed between it and said transmission link member (50) in the direction for being engaged with or disengaged from the teeth (12a) of said ratchet plate (12);
the cam groove (52) in said transmission link member (50) has a force transmission cam groove (53) which is formed such that, when the transmission link member (50) is in the braking position, the force which is applied to the end part (23) of said braking lever (20) can be transmitted to said output link member (30), and a release holding cam groove (54) which, when the force applied to said braking lever (20) is removed, and the braking lever (20) is returned by a return spring (26), causes said transmission link member (50) to be turned to the releasing position, and said turnover spring (45), which has energized said pawl member (40) in the direction for being engaged with the teeth (12a) of said ratchet plate (12), to be inverted such that said pawl member (40) is energized in the direction for being disengaged from the teeth (12a) of said ratchet plate (12);
when a force is applied to the end part (23) of said braking lever (20) for pulling the braking cable (C) in accordance with turning of the braking lever (20) to operate the brake, and then the force is removed, the pawl member (40) engages with the teeth (12a) of the ratchet plate (12) to maintain the braking state; when the braking lever (20) is displaced in the returning direction by the return spring (26), the pawl member (40) is brought into the state in which it is energized in the direction for being disengaged from the teeth (12a) of said ratchet plate (12) while the braking state being maintained; then, when a force is once applied to the braking lever (20) for releasing the brake, the pawl member (40) is disengaged from the teeth (12a) of said ratchet plate (12); then when the force is removed, the braking lever (20) and said output link member (30) are turned in the brake releasing direction for releasing the brake; and then when the braking lever (20) is returned to the original position, said transmission link member (50) is butted against a part of said base (10), being also returned to the original position.
[3] The man-powered braking apparatus (1) of item [1] or [2], wherein an assist spring (55) is provided for turning said transmission link member (50) to the releasing position.
[4] The man-powered braking apparatus (1) of item [1] or [2], wherein said braking lever (20) is that with which a force is applied by treading on the end part (23).
Said present invention functions as follows:
By applying a force to the end part (23) of the braking lever (20) which base part (21) is pivoted to the base (10) fixed to a car body, the output link member (30) is turned in one direction from the non-braking position in accordance with turning of the braking lever (20), being pushed by the base part (21) of the braking lever (20) through the transmission link member (50), and thus the braking cable (C) connected to the output link member (30) can be pulled to generate a braking force.
In other words, when a force is applied to the end part (23) of the braking lever (20), the force is transmitted from the power transmission pin (25) fixedly installed to the base part (21) of the braking lever (20) to the force transmission cam groove (53) of the cam groove (52) in the transmission link member (50), and the force is transmitted to the output link member (30) to which the braking cable (C) is connected, the output link member (30) being turned with the braking cable (C) being pulled.
When the output link member (30) is turned, the pawl member (40), which is pivoted to the output link member (30), is moved, being kept engaged with the teeth (12a) of the ratchet plate (12), which is fixedly installed to the base (10). Then, in a position where a moderate braking force is provided, removing the force from the end part (23) of the braking lever (20) to release it will cause the pawl member (40) to be kept engaged with the teeth (12a) at that position for preventing the output link member (30) from being returned, and thus maintaining the braking state.
The transmission link member (50) is pivoted to the output link member (30) such that it is capable of being rocked between the braking position and the releasing position, and when a force is applied to the end part (23) of the braking lever (20), the transmission link member (50) is in the braking position. When the braking lever (20) is released, the braking lever (20) is returned toward the releasing position by the force of the return spring (26). And the power transmission pin (25) fixedly installed to the base part (21) of the braking lever (20) is moved, being kept fitted into the cam groove (52) in the transmission link member (50), and is shifted from the force transmission cam groove (53) to the release holding cam groove (54). The braking lever (20) is returned by the amount corresponding to the play for this shift, however, by providing the cam groove (52) with an appropriate geometry, the play can be minimized.
The pawl member (40) is capable of being kept energized by the turnover spring (45) disposed between it and the transmission link member (50) in the direction for being engaged with or disengaged from the teeth (12a) of the ratchet plate (12), and when a force has been applied to the end part (23) of the braking lever (20) for the first time, the pawl member (40) is energized in the direction for being engaged with the teeth (12a) of the ratchet plate (12).
When the force applied to the braking lever (20) is removed, the braking lever (20) being returned by the return spring (26), the power transmission pin (25) for the braking lever (20) is moved, being kept fitted into the cam groove (52) in the transmission link member (50), and is shifted from the force transmission cam groove (53) to the release holding cam groove (54), the transmission link member (50) being turned to the releasing position, and the turnover spring (45), which has energized the pawl member (40) in the direction for being engaged with the teeth (12a) of the ratchet plate (12), is inverted such that the pawl member (40) is energized in the direction for being disengaged from the teeth (12a) of the ratchet plate (12). When the pawl member (40) is engaged with the teeth (12a) of the ratchet plate (12) by the braking force, the pawl member (40) will not be disengaged, being held by the friction force, even if the direction in which the pawl member (40) is energized is inverted.
Thus, when a force is applied to the end part (23) of the braking lever (20), the braking lever (C) being pulled in accordance with turning of the braking lever (20) for braking, and then the force is removed, the pawl member (40) is engaged with the teeth (12a) of the ratchet plate (12) to maintain the braking state, and when the braking lever (20) is displaced in the returning direction by the return spring (26), the pawl member (40) is brought into the state in which it is energized in the direction for being disengaged from the teeth (12a) of the ratchet plate (12) while the braking state being maintained.
Then, when a force is once applied to the braking lever (20) for releasing the brake from the braking state, the pawl member (40) is disengaged from the teeth (12a) of the ratchet plate (12) by the energizing force of the inverted turnover spring (45), then, removing the force at that point allows the braking lever (20) and the output link member (30) to be turned in the brake releasing direction for releasing the brake. When the braking lever (20) is returned to the original position, the transmission link member (50) is butted against a part of the base (10), the transmission link member (50) being also returned to the braking position as the original position.
In one embodiment in which the braking cable (C) is connected to the output link member (30), being wound thereon, the braking cable (C) is smoothly pulled by the circumference of the output link member (30) for generation of the braking force. In one embodiment in which the transmission link member (50) is pivoted to the output link member (30) coaxially with the pawl member (40), the linking is simplified, which results in easier layout. In one embodiment in which an assist spring (55), which causes the transmission link member (50) to be turned to the releasing position, is provided, the transmission link member (50) is positively turned from the braking position to the releasing position. In one embodiment in which the braking lever (20) is of treadle-powered type, foot, which is rather inconvenient, as compared to hand, can be used to apply a force to the end part (23) for the proper operation of the man-powered braking apparatus (1).
Hereinbelow, an exemplary embodiment of the present invention will be described with reference to the drawings.
With a man-powered braking apparatus 1, the base part 21 of a braking lever 20 is rockably pivoted to a base 10 fixed to a car body by a main support shaft 11, and the end part 23 of the braking lever 20 is extended to the vicinity of the operator. Brake is applied by exerting a force on a toe shoe 23a in the end part 23 for pulling a braking cable C in accordance with turning of the braking lever 20. In the present embodiment, the braking lever 20 is of treadle-powered type, which permits a force to be applied by treading on the toe shoe 23a in the end part 23, but the braking lever 20 may be adapted to be operated by hand.
An output link member 30 to which the braking cable C is connected, being wound thereon, is pivoted to the base 10 coaxially with the braking lever 20 by means of the main support shaft 11; a pawl member 40 which is engaged with teeth 12a of a ratchet plate 12 fixedly installed to the base 10 to maintain the braking state is pivoted to the output link member 30 by means of a pivot pin 41; and a transmission link member 50 disposed between the braking lever 20 and the output link member 30 is pivoted to the output link member 30 coaxially with the pawl member 40 by means of the pivot pin 41. A coaxial design is not a must, but it renders the construction simpler.
The output link member 30 is pushed by the base part 21 of the braking lever 20 through the transmission link member 50, being turned in one direction from the non-braking position to pull the braking cable C connected to the output link member 30, being wound thereon, for generation of a braking force. The braking cable C may be simply connected to the output link member 30 without being wound thereon.
The transmission link member 50 is pivoted to the output link member 30 by the pivot pin 41 such that it is capable of being rocked between the braking position and the releasing position, and has a cam groove 52 which is fitted with a power transmission pin 25 fixedly installed to the base part 21 of the braking lever 20.
The pawl member 40 is supported such that it is capable of being kept energized by a turnover spring 45 disposed between it and the transmission link member 50 in the direction for a pawl end 42 being engaged with or disengaged from the teeth 12a of the ratchet plate 12.
The cam groove 52 in the transmission link member 50 has a force transmission cam groove 53 which is formed such that, when the transmission link member 50 is in the braking position, a force which is applied to the toe shoe 23a in the end part 23 of the braking lever 20 can be transmitted to the output link member 30, and a release holding cam groove 54 which, when the force applied to the braking lever 20 is removed, and the braking lever 20 is returned by a return spring 26, causes the transmission link member 50 to be turned to the releasing position, and the turnover spring 45, which has energized the pawl member 40 in the direction for being engaged with the teeth 12a of the ratchet plate 12, to be inverted such that the pawl member 40 is energized in the direction for being disengaged from the teeth 12a of the ratchet plate 12.
The man-powered braking apparatus 1 is configured such that, even when a force is applied to the toe shoe 23a in the end part 23 of the braking lever 20 for pulling the braking cable C in accordance with turning of the braking lever 20 to operate the brake, and then the force is removed, the pawl end 42 of the pawl member 40 engages with the teeth 12a of the ratchet plate 12 to maintain the braking state.
When the braking lever 20 is displaced in the returning direction by the return spring 26, the pawl member 40 is brought into the state in which it is energized in the direction for being disengaged from the teeth 12a of the ratchet plate 12 while the braking state being maintained; then, when a force is once applied to the braking lever 20 for releasing the brake, the pawl end 42 of the pawl member 40 is disengaged from the teeth 12a of the ratchet plate 12; then when the force is removed, the braking lever 20 and the output link member 30 are turned in the brake releasing direction for releasing the brake; and then when the braking lever 20 is returned to the original position, a return pin 56 of the transmission link member 50 is butted against a return end 15 formed as a part of the base 10, the transmission link member 50 also being returned to the original position.
In addition, an assist spring 55, which causes the transmission link member 50 to be turned from the braking position to the releasing position, is provided.
Next, the function will be described.
By treading on the toe shoe 23a in the end part 23 of the braking lever 20 which base part 21 is pivoted to the base 10 fixed to a car body, the output link member 30 is turned in one direction from the non-braking position in accordance with turning of the braking lever 20, being pushed by the base part 21 of the braking lever 20 through the transmission link member 50, and thus the braking cable C connected to the output link member 30 can be pulled to generate a braking force.
In other words, when the toe shoe 23a in the end part 23 of the braking lever 20 is treaded to apply a force from the original position before braking as shown in
When the output link member 30 is turned as shown in
The transmission link member 50 is pivoted to the output link member 30 such that it is capable of being rocked between the braking position and the releasing position, and when a force is applied to the end part 23 of the braking lever 20, the transmission link member 50 is in the braking position. When the toe shoe 23a in the end part 23 of the braking lever 20 is released, the braking lever 20 is turned around the main support shaft 11 to be returned toward the releasing position by the force of the return spring 26. And the power transmission pin 25 fixedly installed to the base part 21 of the braking lever 20 is moved, being kept fitted into the cam groove 52 in the transmission link member 50, and is shifted from the force transmission cam groove 53 to the release holding cam groove 54. The braking lever 20 is returned by the amount corresponding to the play for this shift, however, by providing the cam groove 52 with an appropriate geometry, the play can be minimized.
The pawl member 40 is capable of being kept energized by the turnover spring 45 disposed between it and the transmission link member 50 in the direction for being engaged with or disengaged from the teeth 12a of the ratchet plate 12, and when a force has been applied to the end part 23 of the braking lever 20 for the first time, the pawl member 40 is energized in the direction for being engaged with the teeth 12a of the ratchet plate 12.
When the force applied to the braking lever 20 is removed, the braking lever 20 being returned by the return spring 26, as shown in
When the braking lever 20 is fully returned, the turnover spring 45, which has energized the pawl member 40 in the direction for being engaged with the teeth 12a of the ratchet plate 12, is inverted such that the pawl member 40 is energized in the direction for being disengaged from the teeth 12a of the ratchet plate 12, as shown in
Thus, when a force is applied to the end part 23 of the braking lever 20, the braking lever C being pulled in accordance with turning of the braking lever 20 for braking, and then the force is removed, the pawl member 40 is engaged with the teeth 12a of the ratchet plate 12 to maintain the braking state, and when the braking lever 20 is displaced in the returning direction by the return spring 26, the pawl member 40 is brought into the state in which it is energized in the direction for being disengaged from the teeth 12a of the ratchet plate 12 while the braking state being maintained.
Then, when a force is once applied to the braking lever 20 for releasing the brake from the braking state, the friction between the pawl end 42 of the pawl member 40 and the teeth 12a of the ratchet plate 12 is eliminated, and the pawl member 40 is disengaged from the teeth 12a of the ratchet plate 12 by the energizing force of the inverted turnover spring 45, as shown in
Then, removing the force at that point allows the braking lever 20 and the output link member 30 to be turned in the brake releasing direction for releasing the brake, as shown in
In one embodiment in which the braking cable C is connected to the output link member 30, being wound thereon, the braking cable C is smoothly pulled by the circumference of the output link member 30 for generation of the braking force. In one embodiment in which the transmission link member 50 is pivoted to the output link member 30 coaxially with the pawl member 40, the linking is simplified, which results in easier layout.
In one embodiment in which the assist spring 55, which causes the transmission link member 50 to be turned to the releasing position, is provided, the transmission link member 50 is positively turned from the braking position to the releasing position. In one embodiment in which the braking lever 20 is of treadle-powered type, foot, which is rather inconvenient, as compared to hand, can be used to apply a force to the end part 23 for the proper operation of the man-powered braking apparatus 1.
With the man-powered braking apparatus according to the present invention, the transmission link member is rocked to switch over between the braking position and the releasing position, and the cam groove determines the positional relationship, thus smooth and positive operation is assured.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-142301 | May 2004 | JP | national |
