JPH07205777A - Parking brake operating device - Google Patents

Abstract

PURPOSE:To almost fixedly maintain height of an operating lever regardless of an operating amount of pressing in a release knob and further to surely return it to the initial position while preventing a tooth tip of a pole from being damaged, in a parking brake device restricting an original position of the operating lever by bringing the pole into contact with a sector. CONSTITUTION:In a pole 26 mounted on an operating lever turnably around a pin 28, in an opposite side to a ratchet 24 from a tooth tip 36 in around the axial center O, a protrusion 28, protruded from the axial center O more than the tooth tip 36, is provided, and on the other hand, a contact surface 42 of a stopper part 40, integrally provided with a sector 12 in order to restrict an original position of the operating lever by coming into contact with this protrusion 38, is formed into a circular arc shape with the axial center O serving as almost the center in a condition coming into contact with the protrusion 38.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parking brake operating device, and more particularly to improvement of means for defining an original position of an operating lever.

[0002]

2. Description of the Related Art Most parking brake operating devices provided in an automobile or the like are supported by a sector (a) fixedly positioned and a sector (b) rotatably supported around a rotary shaft. And an operating lever which is rotated from the original position to operate the parking brake, and (c)
A ratchet formed on the sector along one arc centering on the rotation axis, and (d) attached to the operation lever so as to be rotatable about an axis parallel to the rotation axis.
A pawl for preventing the operation lever from returning to the original position by being engaged with the ratchet,
(E) It is provided at the tip of the operation lever so that it can be pushed in against the urging force of a return spring, and is mechanically connected to the pawl. And a release knob for releasing the engagement of the.

In such a parking brake operating device, the operating lever is rotated from its original position to a state in which the brake cable connected to the operating lever is tightened, for example, and the pole is meshed with the ratchet, While the parking brake is maintained in the operating state, the operating state of the parking brake is released by rotating the operating lever back to its original position with the release knob pushed in and the pawl and ratchet disengaged. It In that case, is the original position of the operating lever defined by the stopper pin fixed to the operating lever being brought into contact with the sector as described in, for example, Japanese Utility Model Laid-Open No. 5-56709. Alternatively, as shown in FIG.
Is defined by being brought into contact with a stopper portion 78 provided on the front side (lower left side in the figure) of the sector 74 with respect to the ratchet 76.

[0004]

However, if the stopper pin fixed to the operating lever is used to define the original position, the cost is increased due to an increase in the number of parts and assembling steps, which is not preferable. On the other hand, when the tooth tip of the pole is brought into contact with the stopper portion of the sector to define the original position, the number of parts is small and the cost is low, but the tooth tip of the pole may be damaged at the time of contact with the stopper portion. In addition, there is a problem that the height of the operating lever varies depending on the posture of the pole when it abuts against the stopper portion, or the return of the release knob is incomplete.

A detailed description will be given with reference to FIG.
Since the stopper portion 78 that defines the original position includes the flat contact surface 80, the posture of the pole 70 when the tooth tips 72 of the pole 70 are in contact with the contact surface 80, that is, the operation lever is If the rotation position around the attached pin 82 is different as shown by the solid line or the chain double-dashed line depending on the pushing operation amount of the release knob, the pin 82 is accordingly changed.
The position of, and further, the height position of the operation lever may change, which may cause the driver to feel uncomfortable. When the tip 72 of the pole 70 contacts the contact surface 80 at a contact angle α larger than 90 ° as shown by the solid line, the pole 70 contacts the contact surface 80 due to the weight of the operating lever and the tension of the brake cable. By being pressed against the contact surface 80, the force F that attempts to rotate the pole 70 clockwise due to the pressing force P thereof.
Therefore, even if the pushing operation force of the release knob is released, the pawl 70 does not rotate counterclockwise due to the turning force F and the frictional resistance between the pawl 70 and the contact surface 80, and the release knob is moved to the pushing position. It may not return to the initial position where it stays and sticks out from the tip of the operating lever. In that case, when the pole 70 is rotated by the urging force of the return spring due to vibration during traveling and the tooth tip 72 comes into contact with the end portion 84 of the ratchet 76 which is the original position, an unexpected noise is generated. It causes the feeling to deteriorate. If the biasing force of the return spring is increased, the pole 70 can be rotated counterclockwise regardless of the turning force F and the frictional resistance. In that case, when the release knob is pushed in, It is not preferable because the operation force required for the operation is large.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to damage a tip of a pole of a parking brake operating device in which the pole is brought into contact with a sector to define an original position. The height of the operating lever can be maintained substantially constant regardless of the amount of pushing operation of the release knob, and the release knob can be reliably returned to the initial position according to the biasing force of the return spring.

[0007]

In order to achieve the above object, the present invention provides (a) a sector fixedly arranged,
(B) An operation lever that is rotatably supported by the sector about a rotation axis and is rotated from its original position to operate a parking brake; and (c) the sector is centered on the rotation axis. And (d) the operation lever is attached to the operation lever so as to be rotatable about an axis parallel to the rotation axis and meshed with the ratchet. And (e) is provided at the tip of the operating lever so that it can be pushed against the biasing force of the return spring and is mechanically connected to the pole, and A parking brake operating device comprising: a release knob that is operated to rotate the pawl to release the engagement with the ratchet. A projection integrally projecting from the one axial center on the side opposite to the ratchet tip of the pawl that engages with the ratchet around the axis, and protruding outward from the tooth tip from the one axis center; g) When the operation lever makes the return rotation, it comes into contact with the projection to define the original position of the operation lever, and has an arc shape with the one axis of the pawl in the contact state as the center. The contact surface is provided, and the stopper is integrally provided in the sector.

[0008]

In the above parking brake operating device, when the operating lever is rotated to the original position side, the projection provided on the pole comes into contact with the stopper provided on the sector and the original position of the operating lever is reached. The position is defined. This protrusion is provided on the side opposite to the ratchet tip of the pole, that is, on the rotation direction side where the engagement with the ratchet is disengaged, projecting from the one axis center of the pivot center of the pole to the outside of the tooth tip. On the other hand, since the stopper has an arcuate contact surface with the above-mentioned uniaxial center of the pole in contact with the projection as a center, the stopper rotates in response to the pushing amount of the release knob. Even if the posture of the pole is different, the projection always comes into contact with the contact surface to secure a gap between the tip of the pole and the stopper, and the position of the uniaxial center at the time of contact and further operation The position of the lever is positioned substantially constant. This basically prevents the tooth tip of the pole from being damaged, and the height position when the operating lever is returned to the original position is always kept constant regardless of how much the release knob is pushed, making the driver feel uncomfortable. It does not occur.

Further, since the contact surface has an arcuate shape with the uniaxial center at the time of contact with the pole as the center, the contact direction of the pole when the protrusion contacts is always substantially relative to the contact surface. Unnecessary turning force that hinders the rotation of the pawl does not act as in the conventional case where the tip of the tooth is vertical and abuts against the stopper having a flat abutment surface at an indefinite angle. Therefore, when the pushing operation force of the release knob is weakened, the pawl is swung along the contact surface of the stopper promptly to the ratchet side according to the urging force of the return spring, even if some frictional resistance is generated, and the release knob is released. Is reliably returned to the initial position, and it is possible to avoid the conventional return failure and the generation of abnormal noise after a lapse of time.

On the other hand, since the protrusion and the stopper can be integrally provided on the pole and the sector, respectively, it is possible to avoid an increase in cost due to an increase in the number of parts and the number of assembly steps.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. In FIG. 1, a parking brake operating device 10 includes a sector 12 fixed to a floor of a vehicle body (not shown), an operating lever 16 rotatably supported on the sector 12 around a pin 14 as a rotating shaft, and the like. Consists of The operation lever 16 is provided with a brake cable 20 via a cable guide 18 provided on the base end side thereof.
One end of is connected to a cable locking portion (not shown), and a resin grip 22 is fitted on the tip side,
By gripping the grip 22 and rotating the pin 14 in the clockwise direction in FIG. 1, the brake cable 20 is tightened and the parking brake (not shown) to which the other end of the brake cable 20 is connected is operated. It is like this.

A ratchet 24 is formed on the sector 12 along an arcuate shape centered on the pin 14, while a pole 26 meshed with the ratchet 24 is formed on the operating lever 16 in parallel with the pin 14. It is arranged to be rotatable around the pin 28. The axis O of the pin 28 (Fig. 2
(See) corresponds to the uniaxial center. Ratchet 24 and pole 2
The relative positional relationship with 6 is from the state of FIG.
Is determined so that the pawl 26 meshes with the ratchet 24 by rotating it clockwise more than a predetermined angle in the figure, and the range in which the ratchet 24 is formed is not loose due to the use of the brake cable 20. Considering this, it is set so that the pole 26 can be meshed in an angular range that is larger than the rotation stroke of the operation lever 16 required to tighten it by a predetermined amount. Both of the ratchet 24 and the pole 26 have strength capable of withstanding a load applied based on the tension of the brake cable 20.

A release knob 32 is provided at the tip of the grip 22 so that it can be pushed against the urging force of a return spring 30 disposed therein, and the release knob 32 has one end of a release rod 34. Are integrally connected. The return spring 30
The release knob 32 and the release rod 34 are configured such that one end thereof abuts on the release knob 32 and the other end abuts on an engaging portion (not shown) bent and raised inward in the distal end side cylindrical portion of the operation lever 16. The release knob 32 is urged in the direction in which the release knob 32 projects from the grip 22, that is, in the substantially leftward direction in the drawing. The other end of the release rod 34 is connected to a pole 26 so as to be relatively rotatable about an axis parallel to the pin 28. The pole 26 is moved to the left in FIG. 1 based on the biasing force of a return spring 30. Circular turning force is acting. The tooth tip 36 of the pole 26 biting into the ratchet 24 comes into contact with the sector 12 by the turning force, whereby the initial position of the release knob 32 protruding from the grip 22 is defined.

As can be seen from FIG. 2, which shows the pole 26 and a part of the sector 12 in an enlarged detail, the pole 26
Around the pin 28, on the side opposite to the ratchet 24 with respect to the tooth tip 36, that is, on the rotation direction side where the engagement with the ratchet 24 is disengaged (left side in FIG. 2), the tooth from the axis O of the pin 28 is A protrusion 38 is integrally provided so as to protrude outside the tip 36. The protrusion 38 has an arc shape that is rounded with a curvature larger than the rotation locus around the axis O. On the other hand, in the sector 12, a stopper portion 40 that abuts the projection 38 and defines the original position of the operation lever 16 when the operation lever 16 is rotated counterclockwise of the pin 14, is provided on the front side of the ratchet 24. That is, it is integrally provided on the lower left side in FIG. As is apparent from the figure, the stopper portion 40 is provided with the protrusion 3 of the pole 26.
In the state where 8 is in contact, the contact surface 42 having an arc shape centered on the axis O of the pin 28 is provided. In other words, the contact surface 42 has an arc shape with a radius of curvature R equal to the dimension from the axis O to the tip of the protrusion 38. The stopper portion 40 corresponds to a stopper.

Next, the operation of the parking brake operating device 10 configured as described above will be described. Operating lever 1
When 6 is rotated clockwise from the original position shown in FIG. 1 to the pin 14, the brake cable 20 is tightened and the parking brake is operated. At this time, the pawl 26 repeatedly rotates around the pin 28 against the biasing force of the return spring 30 in accordance with the turning operation, whereby the tooth tip 36 is moved while sequentially overcoming the teeth of the ratchet 24. , The tooth of the ratchet 24 and the tooth tip 36 of the pawl 26 that are meshed at the time when the rotation operation is stopped maintain the meshing, so that the return rotation of the operation lever 16 is blocked and the parking brake is operated. The state is maintained.

On the other hand, when the release lever 32 is pushed in against the urging force of the return spring 30 while the operating lever 16 is further pulled up and held, the pole 26 is rotated clockwise about the pin 28. The engagement between 26 and ratchet 24 is released. When the operation lever 16 is rotated counterclockwise in that state, the brake cable 20 is loosened, the operation of the parking brake is released, and the operation lever 16 is moved to the original position where the protrusion 38 of the pole 26 contacts the stopper portion 40. Is returned, the grip 22 is returned to the initial position.

Here, the attitude of the pole 26 at the time of contact, that is, the rotational position around the axis O, differs depending on the amount of pushing operation of the release knob 32, as shown by the one-dot chain line and two-dot chain line in FIG. Since the projection 38 projects outward from the tooth tip 36 and the contact surface 42 has an arc shape centered on the axis O, the projection 38 always contacts the contact surface irrespective of the posture of the pole 26. It is brought into contact with 42, and a predetermined gap is secured between the tip 36 of the pole 26 and the stopper 40. That is, the tooth tip 36 of the pole 26 does not participate in the abutment for defining the original position of the operating lever 16, so that the tooth tip 36 may be damaged and the meshing function with the ratchet 24 may be impaired. There is no. Also,
Since the position of the shaft center O does not change in any contact state, the operation lever 16 is always positioned at a fixed rotation end position, that is, the original position, and the position of the grip 22 when the operation lever 16 is returned. Is kept constant and the driver does not feel uncomfortable.

Since the contact surface 42 has an arc shape centering on the axis O when the pole 26 is in contact, the contact point between the protrusion 38 and the contact surface 42 when contacting is the axis O. Since the contact direction of the pole 26 is always perpendicular to the contact surface 42 on the line connecting the arcuate center of curvature of the protrusion 38, the teeth of the stopper portion having a flat contact surface are formed. As in the case of FIG. 3 where the tip forms an indefinite angle and abuts, no component force is generated in the direction away from the ratchet, and the pole 2
Unnecessary turning force that hinders the return rotation of 6 does not act. For this reason, if the pushing operation force of the release knob 32 is weakened, even if some frictional resistance may occur, the pawl 26 slides along the abutting surface 42 of the stopper portion 40 promptly according to the urging force of the return spring 30. Then, it is rotated to the ratchet 24 side. At this time, the operating lever 16
The urging force of the return spring 30 is determined so that the pole 26 can be rotated against the frictional resistance even when the brake cable 20 has tension in addition to its own weight. Since a turning force that hinders the return rotation of the pole 26 is not generated, a large biasing force that hinders the pushing operation of the release knob 32 is not necessary.
By the return rotation of the pawl 26, the tooth tip 36 reaches the original position shown by the solid line in FIG. 2, that is, the end 44 of the ratchet 24, and the release knob 32 is reliably returned to the initial position. It is possible to avoid the occurrence of a defective return or the generation of abnormal noise after a lapse of time as in the conventional example of No. 3.

Further, in this embodiment, since the projection 38 and the stopper portion 40 are formed integrally with the pole 26 and the sector 12, respectively, an increase in cost due to an increase in the number of parts and assembling steps can be avoided.

Further, in this embodiment, since the projection 38 has an arc shape, deformation and wear due to abutting and sliding contact with the abutment surface 42 are small, and the pole 26 including the projection 38 is compactly constructed. While maintaining the height position of the operating lever 16 substantially constant for a long period of time, and preventing contact between the tooth tip 36 and the contact surface 42, excellent durability is obtained.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, in the above embodiment, the projection 38 and the stopper portion 40 were integrally formed with the pole 26 and the sector 12, respectively, but they are separately formed and integrally fixed in advance prior to the assembling process. You may set it up. In that case, attach the protrusion or stopper to the pole 2.
6 and the sector 12 may be made of different materials.

Further, in the above-described embodiment, the tip of the projection 38 has an arc shape rounded with a relatively large curvature.
If the shaft center O of the pin 28 is positioned at a substantially constant position irrespective of the rotation posture of the pawl 26 at the time of contact with the stopper portion 40, the tip shape of the protrusion 38 can be arbitrarily changed.

Further, in the above-described embodiment, the return spring 30 is constituted by the compression coil spring arranged between the release knob 32 and the locking portion of the operating lever 16, but, for example, the pole 26 and the operating lever 16 are provided. It may be constituted by a tension coil spring or a torsion coil spring which is disposed straddling.

Further, in the above embodiment, the protrusion 38 is the pole 2
6 is provided integrally with the stopper 6 and is slidably contacted with the contact surface 42 at the time of rotation in the contact state with the stopper portion 40. However, the pole 26 can be relatively rotated about an axis parallel to the pin 28. A protrusion may be formed by a rolling element such as an attached roller or a ball so that the protrusion can be rolled with respect to the contact surface 42.

In the above embodiment, the arc shape of the contact surface 42 is defined around the axis O when the pole 26 is in contact, but the operation lever when the operation lever 16 is returned to its original position. The center of curvature of the contact surface 42 may be slightly displaced from the axis O as long as the height of 16 is substantially constant and the driver does not feel uncomfortable. For example, when the curvature center is shifted to the right of the axis O in FIG. 2, the pole 26 can be swung more quickly by the urging force of the return spring 30 when the release knob 32 is released.

Although not illustrated one by one, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a front view showing a parking brake operating device according to an embodiment of the present invention with a part cut away.

FIG. 2 is an enlarged detailed view of a part of a pole and a sector in the apparatus of FIG.

FIG. 3 is a diagram illustrating a contact relationship between a pole and a sector in a conventional parking brake operating device.

[Explanation of symbols]

 10: Parking brake operating device 12: Sector 14: Pin (rotating shaft) 16: Operating lever 24: Ratchet 26: Pole 30: Return spring 32: Release knob 36: Tooth tip 38: Protrusion 40: Stopper (stopper) 42: Contact surface O: Center axis (uniaxial center)

Claims (1)

[Claims] 1. A sector disposed in a fixed position, an operation lever rotatably supported by the sector about a rotation axis, and operated to rotate from an original position to operate a parking brake. A ratchet formed on the sector along an arc centered on the rotation axis, and attached to the operation lever so as to be rotatable about an axis parallel to the rotation axis and meshed with the ratchet. And a pole for preventing the operation lever from returning to the original position, and a pole provided at the tip of the operation lever for pushing operation against the biasing force of the return spring and mechanically connected to the pole. And a release knob for releasing the meshing with the ratchet by rotating the pawl by pushing the parking brake operating device. A projection integrally provided on the pawl that protrudes outward from the tooth tip from the uniaxial center on the side opposite to the ratchet tip of the pawl that engages with the ratchet around the uniaxial center And, when the operation lever is returned and rotated, abuts on the protrusion to define the original position of the operation lever, and has an arc shape with the uniaxial center of the pole in the abutting state as a center. A parking brake operating device comprising a contact surface and a stopper integrally provided in the sector.