Parking brake device

Abstract

To provide a parking brake device that can reduce electromagnetic noise, vibration, and the like while reducing the risk of damage to resin members.SOLUTION: A parking brake device of the present invention comprises a parking gear that is provided on a power transmission shaft and has a plurality of teeth, a parking lock pole having a protrusion that can mesh between adjacent teeth of the parking gear, a shaft that is rotationally driven by an actuator, a detent plate that rotates with the rotation of the shaft, and a detent spring that elastically holds the detent plate at a specific position corresponding to a shift range. The detent plate has a lock valley portion and an unlock valley portion, which are formed across a crest portion along a rotation direction of the detent plate, and the detent spring is provided with a roller made of an insulating resin member that can engage with either of the lock valley portion and the unlock valley portion in association with rotation of the detent plate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a parking brake device. [Background technology]

[0002] Patent Document 1 discloses a technology in which a resin member is placed in part of a parking brake device to reduce mechanical noise such as the sound of parts coming into contact with each other, and the connecting part of the resin member is set in a position away from the load input line to effectively prevent the resin member from peeling off or shifting. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-177546 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a parking brake device, it is desirable to reduce electromagnetic noise and vibration while reducing the risk of damage to resin members.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a parking brake device that can reduce electromagnetic noise, vibration, etc. while reducing the risk of damage to resin members. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the parking brake device of the present invention is a parking brake device comprising: a parking gear provided on a power transmission shaft and having a plurality of teeth; a parking lock pole having a protrusion that can mesh between adjacent teeth of the parking gear; a shaft that is rotated by an actuator; a detent plate that rotates with the rotation of the shaft; and a detent spring that elastically holds the detent plate at a specific position corresponding to a shift range, wherein the detent plate has a lock valley portion and an unlock valley portion formed in between by a peak portion along the rotation direction of the detent plate, and the detent spring is provided with a roller made of an insulating resin member that can engage with either the lock valley portion or the unlock valley portion as the detent plate rotates. Effect of the Invention

[0007] The parking brake device according to the present invention has the advantage of being able to reduce electromagnetic noise, vibration, and the like while reducing the risk of damage to resin members. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a parking brake device according to an embodiment. [Diagram 2] FIG. 2 is an enlarged view of the connection portion between the actuator and the shaft. [Diagram 3] FIG. 3 is an enlarged view of a connection portion between the detent plate and the shaft. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a parking brake device according to the present invention will be described. However, the present invention is not limited to the embodiment.

[0010] FIG. 1 is a diagram showing a schematic configuration of a parking brake device 1 according to an embodiment. The parking brake device 1 according to the embodiment is mounted on a vehicle and configured to be switchable between a locked state in which a power transmission shaft cannot rotate and an unlocked state in which the power transmission shaft can rotate, corresponding to a shift range (such as a P range and a D range). The power transmission shaft is provided, for example, in an automatic transmission installed in a transaxle of the vehicle, and configured to transmit power for traveling the vehicle. The parking brake device 1 according to the embodiment includes a parking gear provided on the power transmission shaft, a parking pole 2, a parking rod 3, a detent plate 4, a detent spring 5, an actuator 6, and the like.

[0011] The parking gear is provided on the power transmission shaft, has a plurality of teeth, and is configured to rotate integrally with the power transmission shaft. The parking pole 2 is disposed near the parking gear, and has a protrusion 2a that can mesh with adjacent teeth of the parking gear. The parking pole 2 is rotatable around a pole shaft 7, and is biased by a return spring 8 in a direction away from the parking gear. The parking rod 3 is connected at one end to the detent plate 4, and is provided with a cam 3a at the other end. The cam 3a is disposed so that the cam surface contacts the end 2b of the parking pole 2 on the opposite side to the pole shaft 7. A guide member 9 is disposed on the opposite side to the end 2b of the parking pole 2 across the cam 3a. The guide member 9 is roller-shaped with a rotation axis perpendicular to the axial direction of the parking pole 2, and the outer circumferential surface of the guide member 9 contacts the cam surface of the cam 3a. The parking rod 3 is configured so that the cam 3a moves in the axial direction while being guided by the guide member 9 when the detent plate 4 rotates.

[0012] The detent plate 4 is integrally provided with one end of the shaft 10 by crimping it to the base end in the longitudinal direction, and is configured to be rotatable with the rotation of the shaft 10. At the tip of the detent plate 4 in the longitudinal direction, a lock valley portion 4a and an unlock valley portion 4b are formed along the rotation direction of the detent plate 4, sandwiching a peak portion. The detent spring 5 is, for example, a leaf spring, and is provided to elastically hold the detent plate 4 at a specific position corresponding to the shift range (P range, D range, etc.). At the tip of the detent spring 5, a roller 5a, which is an engagement member as a rotating structure, is provided rotatably. The roller 5a is configured to be able to engage with either the lock valley portion 4a or the unlock valley portion 4b with the rotation of the detent plate 4. The other end of the shaft 10 is connected to the actuator 6. The actuator 6 is configured to rotate the shaft 10 and the detent plate 4 in response to, for example, a control signal from an electronic control device mounted on the vehicle.

[0013] Next, the operation of the parking brake device 1 will be described. First, when the parking brake device 1 is in an unlocked state and the electronic control device requests that the device be switched to a locked state, the actuator 6 rotates the shaft 10 and the detent plate 4 in a first direction, and the parking rod 3 moves axially toward the cam 3a. As a result, the cam 3a of the parking rod 3 pushes up the parking pole 2 against the biasing force of the return spring, and the protrusion 2a of the parking pole 2 meshes with the parking gear. This brings the power transmission shaft into a locked state in which it cannot rotate. At this time, the roller 5a of the detent spring 5 engages with the lock valley 4a of the detent plate 4, so that the position of the detent plate 4 is maintained and the device is kept in the locked state.

[0014] Furthermore, when the parking brake device 1 is in a locked state and the electronic control device requests that the device be switched to an unlocked state, the actuator 6 rotates the shaft 10 and the detent plate 4 in a second direction opposite to the first direction, and the parking rod 3 moves in the axial direction opposite to the cam 3a side. As a result, the large diameter portion of the cam 3a retreats from the end 2b of the parking pole 2, so that the biasing force of the return spring 8 pushes down the parking pole 2, and the protrusion 2a of the parking pole 2 comes off the parking gear. This brings the power transmission shaft into an unlocked state in which it can rotate. At this time, the roller 5a of the detent spring 5 engages with the unlock valley 4b of the detent plate 4, so that the position of the detent plate 4 is maintained and the device is kept in the unlocked state.

[0015] In the parking brake device 1 according to the embodiment, the roller 5a of the detent spring 5 is made of an insulating resin member. As a result, the parking brake device 1 according to the embodiment can reduce electromagnetic noise transmitted from the actuator 6 via the shaft 10 and the detent plate 4 by the roller 5a engaged with the lock valley portion 4a of the detent plate 4. In addition, since the load applied to the engagement portion between the roller 5a of the detent spring 5 and the lock valley portion 4a of the detent plate 4 is smaller than the load applied to the meshing portion between the protrusion 2a of the parking pole 2 and the parking gear, the risk of damage to the roller 5a made of an insulating resin member can be reduced. Therefore, in the parking brake device 1 according to the embodiment, it is possible to reduce electromagnetic noise, vibration, and the like transmitted from the actuator 6 by the roller 5a while reducing the risk of damage to the roller 5a made of an insulating resin member.

[0016] FIG. 2 is an enlarged view of a connection portion between the actuator 6 and the shaft 10. In the parking brake device 1 according to the embodiment, an annular member 11 made of ferrite may be interposed between the shaft 10 and a cylindrical portion 6a provided at the connection portion on the actuator 6 side in the radial direction of the shaft 10 at the connection portion between the actuator 6 and the shaft 10. As shown in FIG. 2, the shaft 10 is inserted into the hollow interior of the annular member 11, and the inner peripheral surface of the annular member 11 and the outer peripheral surface of the shaft 10 are in contact with each other. In addition, the outer peripheral surface of the annular member 11 and the inner peripheral surface of the cylindrical portion 6a of the actuator 6 are in contact with each other. As a result, the annular member 11 made of ferrite can reduce electromagnetic noise, vibration, and the like propagated from the actuator 6 to the shaft 10.

[0017] 3 is an enlarged view of a connection portion between the detent plate 4 and the shaft 10. In the parking brake device 1 according to the embodiment, a collar 12 made of a resin member may be interposed between the detent plate 4 and the shaft 10 in the radial direction of the shaft 10, and the connection portion between the detent plate 4 and the shaft 10 may have a crimped structure with the collar 12 sandwiched therebetween. In this case, an insulating coating is provided on all of the portions of the detent plate 4 that come into contact with the collar 12 and all of the portions of the shaft 10 that come into contact with the collar 12. As a result, the collar 12 made of a resin member and the insulating coating can reduce electromagnetic noise, vibrations, and the like that are propagated from the actuator 6 to the detent plate 4 via the shaft 10.

[0018] Alternatively, in the parking brake device 1 according to the embodiment, a collar 12 made of an insulating resin member may be interposed between the detent plate 4 and the shaft 10 in the radial direction of the shaft 10, and the connection portion between the detent plate 4 and the shaft 10 may have a crimped structure sandwiching the collar 12. In this way, the collar 12 made of an insulating resin member can reduce electromagnetic noise and vibrations propagated from the actuator 6 to the detent plate 4 via the shaft 10. [Explanation of symbols]

[0019] 1 Parking brake device 2 Parking pole 3 Parking Rod 4 Detent Plate 5 Detent spring 5a Lola 6 Actuators

Claims

[Claim 1] a parking gear provided on the power transmission shaft and having a plurality of teeth; a parking lock pole having a protrusion that can mesh with adjacent teeth of the parking gear; A shaft that is rotationally driven by an actuator; a detent plate that rotates with the rotation of the shaft; a detent spring that elastically holds the detent plate at a specific position corresponding to a shift range; A parking brake device comprising: The detent plate has a lock valley portion and an unlock valley portion formed along a rotation direction of the detent plate, with a peak portion sandwiched therebetween, A parking brake device characterized in that the detent spring is provided with a roller made of an insulating resin material that can engage with either the lock valley portion or the unlock valley portion as the detent plate rotates.

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