JP6157384B2 - Brake device for vehicle - Google Patents

Description

  The present invention relates to a vehicle brake device in which wheel brakes that are operated by an electric actuator when a vehicle is parked are provided on left and right rear wheels, respectively.

  Japanese Patent Application Laid-Open No. H10-228707 discloses a parking brake state in which the left and right rear wheel brakes are driven by an electric actuator disposed substantially at the center of the vehicle.

JP 2002-221244 A

  However, in the device disclosed in Patent Document 1, the electric actuator is arranged at the approximate center of the vehicle, and a special mounting structure such as a bracket for mounting the electric actuator is necessary. It is necessary to route a pair of cables branched to the ring side, and the degree of freedom in cable layout is small.

  SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and eliminates the need for a special mounting structure on the vehicle body side for mounting an electric actuator, and can increase the degree of freedom in cable layout. An object is to provide a brake device.

  In order to achieve the above object, the present invention provides a vehicle brake device in which wheel brakes that are actuated by electric actuators when a vehicle is parked are provided on left and right rear wheels, respectively, on wheels provided on either left or right rear wheels. In addition to the wheel brake, the brake is provided with the electric actuator that exerts power to drive a wheel brake provided on the left or right other rear wheel, toward the wheel brake provided on the other rear wheel. It is a first feature that a cable for transmitting power from the electric actuator is routed.

  According to the present invention, in addition to the configuration of the first feature, the wheel brake is a drum brake having a parking brake lever and entering a parking brake state in accordance with a traction operation of the parking brake lever, The second feature is that the direction of the traction operation of the parking brake lever of the drum brake provided in each is set to be opposite to each other in the vehicle front-rear direction.

  In addition to the configuration of the second feature, the present invention provides the drum brake provided on the one rear wheel with the traction operation direction of the parking brake lever as the rear side in the vehicle front-rear direction. It is a third feature that it is disposed so as to be located behind the axle of the one rear wheel in the mounted state.

  According to the first feature of the present invention, since the electric actuator is disposed on the left and right rear wheel brakes, it is not necessary to provide a special mounting structure such as a bracket for mounting the electric actuator. Also, the mounting property of the electric actuator is improved. In addition, it is only necessary that the cable transmitting power from the electric actuator is routed toward the other rear wheel so that the cable is routed between the left and right rear wheels, increasing the degree of freedom in cable layout. To do.

  According to the second feature of the present invention, the present invention can be preferably applied to a known drum brake having a parking brake lever. In addition, there is a conventionally known drum brake in which the parking brake state is obtained by pulling the parking brake lever forward in the vehicle longitudinal direction. Two such drum brakes are prepared, and one drum brake is prepared. The parking brake lever towing direction of the brake is set to the rear side in the front-rear direction of the vehicle, and the pulling direction of the parking brake lever of the other drum brake is set to the front side in the front-rear direction of the vehicle. It can be used, and the existing drum brake can be used effectively, and the diversion property can be improved.

  Further, according to the third feature of the present invention, since the electric actuator is arranged behind the axle of the left and right rear wheels, most of the components are arranged in front of the axle. By arranging the electric actuator at a position where interference with the electric actuator hardly occurs, the degree of freedom in layout of the electric actuator can be increased. In addition, it is possible to prevent as much as possible that a stepping stone or the like that is bounced off by the front wheel hits the electric actuator.

It is the perspective view which looked at the principal part of the drum brake for left rear wheels from the vehicle width direction outer side. It is the perspective view which looked at the principal part of the drum brake for left rear wheels from the opposite side to FIG. It is the front view which looked at the principal part of the drum brake for left rear wheels from the vehicle width direction outside. FIG. 5 is a perspective view showing a main part of the left rear wheel drum brake as seen from the inner side in the vehicle width direction with a part cut away. It is the schematic which shows the power transmission system for parking of the drum brake for right and left rear wheels of a four-wheel vehicle.

  DESCRIPTION OF EMBODIMENTS Embodiments of the present invention will be described with reference to FIGS. 1 to 5. First, in FIGS. 1 to 3, a left rear wheel, which is a rear wheel on either side of a four-wheel vehicle, is suspended from a vehicle body. A knuckle 13 having a frame-like frame portion 13a is fixed to the rear end of a trailing arm 12 that constitutes a part of the suspension 11 and extends in the front-rear direction of the vehicle. The axle 14 of the left rear wheel disposed in the shaft is rotatably supported by the frame portion 13a.

  A wheel brake provided on the left rear wheel is a drum brake 15, and a back plate 16 of the drum brake 15 is fixed to the frame portion 13a. An anchor block 21 serving as a fulcrum during expansion and contraction of the first and second brake shoes 17 and 18 as a pair of front and rear is fixed to the lower portion of the back plate 16, and the first and second brake shoes 17 and 18 are fixed. Friction linings 19 and 20 that are slidably contactable with a brake drum (not shown) that rotates with the left rear wheel are joined to the outer periphery of the outer periphery.

  A wheel cylinder 22 that exerts a force for expanding the first and second brake shoes 17, 18 is provided on the upper portion of the back plate 16. The outer ends of a pair of pistons 23 included in the wheel cylinder 22 are first and first. The two brake shoes 17 and 18 are fixed so as to face the upper ends of the brake shoes 17 and 18. The wheel cylinder 22 is actuated by the output hydraulic pressure of a master cylinder (not shown) operated by a brake pedal, and drives the first and second brake shoes 17 and 18 in the expansion direction.

  A first coil spring 24 is provided between the lower ends of the first and second brake shoes 17 and 18 to urge the lower ends of the brake shoes 17 and 18 toward the anchor block 21. A second coil spring 25 is provided between the upper ends of the second brake shoes 17 and 18 to urge the brake shoes 17 and 18 in the contraction direction. Further, between the upper portions of the first and second brake shoes 17 and 18, a contraction position restricting strut 28 is provided so as to restrict the contraction position of the brake shoes 17 and 18. The contraction position restricting strut 28 includes a cylindrical body 29 having a first engaging portion 29a at one end portion of the first and second brake shoes 17 and 18 that engages with an upper portion of the first brake shoe 17, and the cylindrical body. A screw shaft 30 having a second engaging portion 30a that is engaged with the upper portion of the second brake shoe 18 at one end thereof, and the other end of the cylindrical body 29; And a ratchet wheel 31 that is screwed onto the screw shaft 30 so as to be in contact with the screw shaft 30.

  An adjustment lever 32 engaged with the outer periphery of the ratchet wheel 31 is rotatably supported by the second brake shoe 18 via a support shaft 33, and a third coil is interposed between the second brake shoe 18 and the adjustment lever 32. A spring 34 is provided. When the first and second brake shoes 17 and 18 are expanded by the operation of the wheel cylinder 22, when the first and second brake shoes 17 and 18 are relatively moved and expanded due to wear of the friction linings 19 and 20, The adjusting lever 32 is rotated around the axis of the support shaft 33 in the clockwise direction in FIG. 3 by the spring force of the third coil spring 34, whereby the ratchet wheel 31 is rotated and the screw shaft 30 is rotated. 3, the effective length of the contraction position regulating strut 28 is increased and corrected.

  By the way, the upper end portion of the parking brake lever 35 extending vertically so as to partially overlap the first brake shoe 17 in front view is connected to the upper portion of the first brake shoe 17 via a pin 36. The upper part of the parking brake lever 35 is engaged with a first engaging portion 29 a of the cylindrical body 29 of the contraction position regulating strut 28. When the vehicle is parked, the parking brake lever 35 is rotated and driven in the counterclockwise direction of FIG. 3, that is, backward in the vehicle front-rear direction, and the second brake shoe is driven by the rotation of the parking brake lever 35. 18, a force in a direction to press the friction lining 20 of the brake shoe 18 against the inner periphery of the brake drum acts through the contraction position regulating strut 28. Further, when the parking brake lever 35 is continuously rotated and driven in the counterclockwise direction of FIG. 3, the parking brake lever 35 has an engagement point with the first engagement portion 29a of the contraction position regulating strut 28 as a fulcrum. In this case, the first brake shoe 17 is expanded through the pin 36, and the friction lining 19 of the first brake shoe 17 comes into pressure contact with the inner periphery of the brake drum. That is, the friction linings 19 and 20 of the first and second brake shoes 17 and 18 are pressed against the inner periphery of the brake drum to obtain a parking brake state.

  Referring also to FIG. 4, the parking brake lever 35 is driven by the power exerted by the electric actuator 38. The electric actuator 38 is attached to the axle 14 of the left rear wheel in a vehicle-mounted state. Fixedly arranged at the rear.

  The drum brake 15 is attached to the left rear wheel in such a posture that the brake is actuated in response to the parking brake lever 35 being actuated backward in the vehicle front-rear direction, and the electric actuator 38 is The parking brake lever 35 is connected to the parking brake lever 35 so as to be pulled rearward in the vehicle front-rear direction.

  The electric actuator 38 includes an electric motor 40 attached to the casing 39 with the rotation axis as the vertical direction, and a power conversion mechanism built in the casing 39 so as to convert the rotational power of the electric motor 40 into a linear force. 44, and a part of the power conversion mechanism 44 includes a gear 45 that rotates in response to the operation of the electric motor 40, and a cylinder that passes through the gear 45 coaxially and is fixed to the gear 45. And a first transmission shaft 48 integrally having a first male screw portion 47 screwed into one end of the rotary tube 46, and a second male screw portion 49 screwed into the other end of the rotary tube 46. It is comprised with the 2nd transmission shaft 50 which has integrally.

  On the inner periphery of the rotary cylinder 46, a first female screw part 51 for screwing the first male screw part 47 and a second female screw part 52 for screwing the second male screw part 49 are arranged in the axial direction of the rotary cylinder 46. The first and second transmission shafts 48 and 50 are drawn into the rotary cylinder 46 by the rotation of the rotary cylinder 46 according to the operation of the electric motor 40. A first male screw portion 47 and a first female screw portion 51, and a second male screw portion 49 and a second female screw portion 52 are formed.

  A cable 53 having one end connected to the first transmission shaft 48 passes through the back plate 16 of the drum brake 15 movably so as to place the drum brake 15 of the left rear wheel in the parking brake state when towing the parking brake. Connected to the lever 35.

  On the other hand, a conventionally well-known drum brake 15 is mounted on the right rear wheel so that a parking brake state can be obtained by pulling the parking brake lever forward in the vehicle longitudinal direction. That is, the direction of the traction operation of the parking brake lever 35 of the drum brake 15 provided on each of the left and right rear wheels is set to be opposite to each other in the vehicle front-rear direction.

  A cable 54 having one end connected to the second transmission shaft 50 to transmit power from the electric actuator 38 is connected from the electric actuator 38 to the drum brake 15 provided on the right rear wheel, as shown in FIG. It is routed and connected to the parking brake lever of the right rear wheel drum brake 15 from the front side in the vehicle longitudinal direction.

  Next, the operation of this embodiment will be described. To the drum brake 15 as a wheel brake provided on the left rear wheel, which is one of the left and right rear wheels, in addition to the drum brake 15, the right wheel, which is the other rear wheel. Since the electric actuator 38 that exhibits the power for driving the drum brake 15 provided on the rear wheel is provided, it is not necessary to provide a special mounting structure such as a bracket for mounting the electric actuator 38. Mounting is also improved. Further, since the cable 54 for transmitting the power from the electric actuator 38 is routed toward the drum brake 15 provided on the right rear wheel, the cable 54 may be routed between the left and right rear wheels. The degree of freedom in cable layout increases.

  In addition, by using the drum brake 15 as the wheel brake to which the present invention is applied, the present invention can be suitably applied to the well-known drum brake 15 having the parking brake lever 35. Moreover, there is a conventionally known drum brake 15 in which a parking brake state can be obtained by pulling the parking brake lever 35 forward in the vehicle longitudinal direction, and two such drum brakes 15 are prepared, A known drum is configured such that the towing direction of the parking brake lever 35 of one drum brake 15 is the rear side in the front-rear direction of the vehicle and the tow direction of the parking brake lever 35 of the other drum brake 15 is the front side in the front-rear direction of the vehicle The brake 15 can be used for the left and right rear wheels, and the existing drum brake 15 can be used effectively and the diversion can be enhanced.

  Furthermore, the electric actuator 38 is located behind the axle 14 of the left rear wheel in the state of mounting the vehicle on the drum brake 15 provided on the left rear wheel with the direction of traction operation of the parking brake lever 35 being the rear side in the vehicle front-rear direction. Therefore, the electric actuator 38 is disposed at a position where most of the components are unlikely to interfere with the components of the suspension 11 arranged in front of the axle 14. The degree of freedom in layout can be increased. Further, it is possible to prevent as much as possible that the stepping stones and the like that have been bounced off by the front wheels hit the electric actuator 38.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

14 ... Axle 15 ... Drum brake 35 as a wheel brake ... Parking brake lever 38 ... Electric actuator 54 ... Cable

Claims (3)

  A wheel brake (15) that is actuated by an electric actuator (38) when the vehicle is parked is provided on each of the left and right rear wheels. In addition to the wheel brake (15), the electric actuator (38) that exerts power to drive the wheel brake (15) provided on either the left or right rear wheel is disposed, and is provided on the other rear wheel. The vehicle brake device is characterized in that a cable (54) for transmitting power from the electric actuator (38) is routed toward the wheel brake (15).   The wheel brake is a drum brake (15) having a parking brake lever (35) and being in a parking brake state in response to a traction operation of the parking brake lever (35). The vehicular brake device according to claim 1, wherein the direction of the traction operation of the parking brake lever (35) of the brake (15) is set to be opposite to each other in the vehicle front-rear direction.   The electric brake (38) is attached to the one of the rear wheels with the electric actuator (38) attached to the one of the rear wheels, with the direction of the traction operation of the parking brake lever (35) being the rear side in the vehicle longitudinal direction. The vehicle brake device according to claim 2, wherein the vehicle brake device is disposed rearward of the rear axle (14).

Images