JPH0790756B2 - Foot-operated parking brake - Google Patents

Description

The present invention relates to a foot-operated parking brake that activates and releases a parking brake of a vehicle such as an automobile.

<Prior Art> With the installation of an automatic transmission, a foot-operated parking brake has been adopted in recent automobiles instead of a side brake that is manually operated.

This foot-operated parking brake includes a brake arm that is rotated by a foot operation to operate the parking brake, and a return spring that returns and rotates the brake arm.

Therefore, the brake arm is urged to return by the return spring, and a lock mechanism that locks the return and maintains the braking state of the parking brake is essential.

Conventionally, as this lock mechanism, a ratchet mechanism has been used that meshes with each other to lock the rotation of the brake arm in the return direction.

<Problems to be Solved by the Invention> However, since ratchet teeth of the ratchet mechanism are always in contact with each other, an abnormal noise is generated when the brake arm is stepped on to operate the parking brake. It's noisy. Further, the ratchet mechanism has a problem that the mechanism itself is large and the mounting space thereof is also large.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a foot-operated parking brake that operates quietly and that can be installed in a small space.

<Means for Solving the Problems> In order to achieve the above object, the present invention provides a brake arm that rotates by a stepping operation to perform a parking brake operation, a return spring that returns and rotates the brake arm, and a brake arm. In a foot-operated parking brake comprising lock means for locking the return and maintaining the braking state of the parking brake, and a lock release member for releasing the lock of the lock means, the lock means comprises:
The coil spring is provided between the support shaft fixed to the vehicle body frame and the brake arm, and is composed only of a coil spring that is locked by a frictional force generated between the support shaft and a sleeve formed on the brake arm that rotates about the support shaft. One end of the coil spring is locked to the support shaft and the other end is locked to the lock releasing member, and the coil portion of the coil spring is externally inserted or inserted in a close contact with the sleeve. The close contact between the sleeve and the sleeve is such that the frictional force between the sleeve and the sleeve gradually increases along the axial direction, and when the lock is released, the coil portion gradually separates from the sleeve from the smaller frictional force. It is characterized by being

<Operation> Since the present invention is configured as described above, the coil spring locks the return rotation of the brake arm against the biasing force of the return spring by the frictional force generated between the sleeves of the brake arm, and the parking brake. To maintain the operating state of. Further, the lock release member releases the frictional force of the coil spring, and acts so as to enable the return rotation of the brake arm by the return spring.

Then, the return rotation of the brake arm is performed at a slow speed.

<Examples> Examples of the present invention will be specifically described below with reference to the drawings. In the illustrated embodiment, the same elements are designated by the same reference numerals, and duplicated description will be omitted.

1 and 2 are a sectional view and a side view of the first embodiment of the present invention, and FIGS. 3 (A) and 3 (B) are A- in FIG.
The A line sectional view and the BB line sectional view are shown.

The support shaft 2 is fixedly attached to the body frame 1 by fitting the left end portion into the body frame 1.
A large diameter portion 2a and a small diameter portion 2b are integrally formed on the support shaft 2, and a brake arm 3 is rotatably attached to the small diameter portion 2b.

The operation of the brake arm 3 is released by a cable for remote operation (not shown). The brake arm 3 is integrally formed with a cylindrical sleeve 4 extending in the direction of the support shaft 2.
Is externally inserted into the small diameter portion 2b of the support shaft 2, so that the brake arm 3 rotates about the support shaft 2. The sleeve 4 has a uniform outer diameter and is formed so that the large diameter portion 2a of the support shaft 2 and the outer peripheral surface are flush with each other.

The return rotation of the brake arm 3 is performed by a spring, and therefore a return spring 5 is provided. In this embodiment, the return spring 5 is composed of a tension spring, and the return spring 5 is stretched between the rod 1a formed on the vehicle body frame 1 and the rod 3a formed on the brake arm 3 so that the brake arm 3 can be returned and rotated. Is urged to.

Reference numeral 6 denotes a coil spring as a locking means, which locks the return rotation of the brake arm 3 by the return spring 5 by the frictional force generated between the return arm 5 and the sleeve 4.
Reference numeral 7 denotes a ring-shaped lock releasing member for releasing the frictional force of the coil spring 6, which is attached so as to rotate around the sleeve 4 of the brake arm 3.

As shown in FIG. 3B, a bracket 7a is formed on the unlocking member 7, and one end of the cable 8 is connected to the bracket 7a. Therefore, when the other end of the cable 8 is pulled, the lock release member 7 rotates, and the lock of the coil spring 6 is released.

The coil spring 6 has a rectangular cross section and has one end
6a is inserted and locked in the radial direction of the support shaft 2, and the other end 6b is inserted and locked in the lock release member 7. The coil portion 6c of the coil spring 6 is externally attached to the large diameter portion 2a of the support shaft 2 and the sleeve 4 of the brake arm 3 in a close contact state.

In this embodiment, the coil portion 6c of the coil spring 6 is formed so that its inner diameter gradually decreases in a free state, and the maximum inner diameter thereof is the large diameter portion 2a of the support shaft 2 and the sleeve 4.
It is wound so that its diameter is slightly smaller than the outer diameter of
At the time of mounting, it is extrapolated with the coil diameter slightly expanded. Therefore, the coil portion 6c of the coil spring 6 tightens the large diameter portion 2a of the support shaft 2 and the sleeve 4 of the brake arm 3 so that the frictional force gradually increases from the sleeve 4 side to the support shaft 2 side. The rotation of the brake arm 3 is locked by the frictional force, which locks the return rotation of the brake arm 3.

Next, the operation will be described. To operate the parking brake, the brake arm 3 is stepped on and the brake arm 3 is rotated in the direction in which the coil spring 6 expands.
This activates the parking brake via the remote control cable. Further, as the brake arm 3 rotates, the return spring 5 extends and energy is accumulated, so that the brake arm 3 is urged to return to rotate around the support shaft 2. However, the coil spring 6 is externally inserted into the sleeve 4 of the brake arm 3, and the return rotation direction of the brake arm 3 is the coil portion 6c of the coil spring 6.
Since the diameter is reduced, the tightening force of the coil spring 6 increases.

As a result, the frictional force of the coil spring 6 acts on the sleeve 4 and the return rotation of the brake arm 3 is locked, and the operating state of the parking brake is maintained.

To release the operation of the parking brake, the cable 8 is pulled. A lock release member 7 is connected to the cable 8, and the lock release member 7 rotates in the direction in which the coil spring 6 expands. Since the other end 6b of the coil spring 6 is locked to the unlock member 7, the coil portion 6c of the coil spring 6 is expanded in diameter and the tightening of the sleeve 4 is released.

As a result, the brake arm 3 is returned and rotated by the urging force of the return spring 5. Therefore, the parking brake is released via the remote control cable. In such an operation, the coil spring 6 gradually separates from the sleeve 4 from the side having a small frictional force, so that the tightening of the coil spring 6 is gradually released. Therefore, the sleeve 4
The sliding frictional resistance between the coil spring 6 and the coil spring 6 is gradually released, and the brake arm 3 returns at a slow speed, so that an operation with less impact can be performed.

Also, in order to perform such an operation reliably, the small diameter part of the support shaft 2
Viscous grease (not shown) may be filled between 2b and the sleeve 4 of the brake arm 3 so that the shearing force of the viscous grease acts.

In this embodiment, since only the coil spring 6 is used as the lock mechanism for the brake arm 3, the operation is quiet. Further, since the coil spring 6 is externally fitted to the support shaft 2 and the sleeve 4, no special mounting space is required, and the size of the entire device can be reduced. Further, when the lock is released, the coil spring 6 gradually separates from the sleeve 4 from the smaller frictional force to the larger frictional force, so that the brake arm 3 returns at a slow speed.

FIG. 4 shows a second embodiment of the present invention. In this embodiment, the sleeve 4 of the brake arm 3 is formed in a cylinder length having a uniform inner diameter, and a hollow drum portion 9 is formed on the outer side of the support shaft 2, and the sleeve 4 is inserted in the drum portion 9. ing.

Further, one end 6a of the coil spring 6 is locked to the bottom surface of the drum portion 9, and the coil portion 6c thereof is inserted into the sleeve 4 having a cylinder length. The coil portion 6c of the coil spring 6 is formed so that its outer diameter gradually increases in a free state, and its minimum outer diameter is wound larger than the inner diameter of the sleeve 4, so that When inserted, the sleeve 4 is pressed against the inside and a frictional force acts.
This locks the return rotation of the brake arm 3.

On the other hand, unlocking is performed by the unlocking member 7, but this unlocking is performed by causing the unlocking member 7 to cooperate with each other in the direction in which the diameter of the coil portion of the lock spring is reduced.

Further, the unlocking member 7 is a cylindrical portion 7b that is externally inserted on the support shaft 2.
And a ring portion 7c extending from the tubular portion 7b in the circumferential direction, and the ring portion 7c is pulled out to the right side of the brake arm 3. In such an embodiment, the lock is released by directly or indirectly rotating the ring portion 7c. Also in this example, the coil portion 6c of the coil spring 6 gradually separates from the sleeve 4 from the side having a small frictional force to the side having a large frictional force, so that the brake arm 3 returns at a slow speed.

FIG. 5 shows a third embodiment of the present invention. This embodiment is the first
It is formed in substantially the same manner as the embodiment. In this case, the sleeve 4 is formed so that the outer diameter thereof gradually decreases toward the lock releasing member 7, while the coil portion 6c of the coil spring 6 has a coil inner diameter smaller than the minimum outer diameter of the sleeve 4 in a free state. It has a uniform inner diameter and is wound into a cylindrical shape.

Further, in the third embodiment, the coil portion 6c is expanded in diameter and is externally fitted to the support shaft 2 and the sleeve 4. In this extrapolated state, the frictional force generated between the coil spring 6 and the sleeve 4 is small on the small diameter side of the sleeve 4 and large on the large diameter side. When the lock release member 7 is rotated in this state, the coil spring 6 gradually separates from the sleeve 4 from the side having a small frictional force, so that the brake arm 3 slowly returns and rotates.

FIG. 6 shows a fourth embodiment of the present invention. As shown in the figure, this embodiment is formed in substantially the same manner as the second embodiment, but the inner surface of the sleeve 4 is tapered so as to gradually increase in diameter toward the lock releasing member 7.

On the other hand, the coil spring 6 is wound into a cylindrical shape having a uniform outer diameter having a coil outer diameter larger than the maximum inner diameter of the sleeve 4 in a free state of the coil portion. The coil spring 6 has a reduced diameter and is inserted into the sleeve 4.

In this inserted state, the frictional force generated between the coil spring 6 and the sleeve 4 is small on the side where the inner diameter of the sleeve 4 is large and is large on the side where it is small.

In this embodiment, by rotating the lock releasing member 7, the diameter of the coil portion of the coil spring 6 is reduced to release the lock. To release the lock, the coil portion of the coil spring 6 is gradually moved from the side with a small frictional force to the side with a large frictional force.
Since the brake arm 3 is moved away from, the return rotation of the brake arm 3 is also performed at a slow speed.

<Effects of the Invention> As described above, according to the present invention, since the locking means for locking the return of the brake arm to maintain the braking state of the parking brake is composed of only the coil spring, it is possible to operate quietly. At the same time, it is possible to achieve a reduction in the number of parts and a drastic downsizing of the device.

In addition, the close contact between the coil spring coil and the sleeve of the brake arm is such that the frictional force between them gradually increases along the axial direction, and when releasing the lock, the sleeve gradually increases from the smaller frictional force to the larger frictional force. Since the coil portions are further separated from each other, the return rotation of the brake arm can be performed at a slow speed, and there is no impact or the like, so that the operability can be made extremely excellent.

[Brief description of drawings]

1, 2 and 3 (A) and (B) are the first of the present invention.
A sectional view of the embodiment, a side view and a sectional view taken along line AA and BB in FIG. 1, FIG. 4 is a sectional view of a second embodiment,
FIG. 5 is a sectional view of the third embodiment, and FIG. 6 is a sectional view of the fourth embodiment. 2 ... Shaft, 3 ... Brake arm, 4 ... Sleeve, 5 Return spring, 6 ... Coil spring, 6a ... One end, 6b ... Other end, 6c ... Coil part, 7 ... Unlock member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-58-118438 (JP, A) JP-A-59-57052 (JP, A) JP-A-59-223543 (JP, A) Actual development Sho-59- 190659 (JP, U) Japanese Patent Sho 56-32134 (JP, B2)

Claims (5)

[Claims] 1. A brake arm that rotates by a foot operation to operate a parking brake, a return spring that returns and rotates the brake arm, and a lock that locks the return of the brake arm and maintains the braking state of the parking brake. And a lock release member for releasing the lock of the lock means, wherein the lock means is provided between a support shaft fixed to a vehicle body frame and a brake arm. A coil spring that locks with a frictional force generated between the sleeve and the sleeve formed on the brake arm that rotates around, and the coil spring has one end locked to the support shaft,
Further, the other end is locked to the lock releasing member, and the coil portion is externally inserted or inserted in the sleeve in a close contact state, and the close contact state between the coil portion and the sleeve causes a frictional force between them. A foot-operated parking brake characterized in that the coil portion is configured to gradually increase along the axial direction, and when the lock is released, the coil portion gradually separates from the sleeve from the side having a smaller frictional force. 2. The coil portion of the coil spring, wherein the sleeve has a uniform outer diameter, and the sleeve has a diameter that gradually increases in the axial direction in a free state and the maximum inner diameter is smaller than the outer diameter of the sleeve. The foot-operated parking brake according to claim (1), in which is attached. 3. The coil portion of the coil spring, wherein the sleeve has a uniform inner diameter, and the sleeve has a diameter that gradually decreases in the axial direction in a free state, and the minimum outer diameter is larger than the sleeve inner diameter. The foot-operated parking brake according to claim (1), which is interpolated. 4. The sleeve is formed so that its outer diameter is gradually reduced, and a coil portion of the coil spring having a uniform inner diameter smaller than the minimum outer diameter of the sleeve is externally inserted into the sleeve in a free state. The foot-operated parking brake according to claim (1). 5. The sleeve is formed so that its diameter gradually increases, and a coil portion of the coil spring having an inner uniform outer diameter larger than a maximum inner diameter of the sleeve in a free state is inserted into the sleeve. Claims (1)
Foot-operated parking brake described in paragraph.