JP4424063B2 - Common use parking brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a service-cum-parking brake device compact-constructive, advantageous in stabilizing parking brake performance and the like, and highly reliable on liquid resistance, sealing performance, heat resistance and the like. <P>SOLUTION: The service-cum-parking brake device A comprises a piston 19 forming a hydraulic pressure chamber Ro in a cylinder part 17b, a brake lining 13a to be pushed by the piston 19 for braking a disc rotor 11, a second piston 25 for partitioning the hydraulic pressure chamber Ro into a first hydraulic pressure chamber R1 and a second hydraulic pressure chamber R2, a friction clutch 27 for allowing the rotation of the second piston 25 when held at a fixed position and for precluding the rotation of the second piston 25 when moved a predetermined distance to the side of the second hydraulic pressure chamber, an adjusting device 29 for adjusting a space between both pistons 19, 25 depending on the wear of the brake lining 13a, and a selector valve 33 mounted in a branch hydraulic pressure circuit 23b which can supply/discharge brake liquid to the second hydraulic pressure chamber R2 for selectively communicating/interrupting the first hydraulic pressure chamber R1 with/from the second hydraulic pressure chamber R2. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  INDUSTRIAL APPLICABILITY The present invention can be employed as a brake device for a vehicle, and is not only used as a service brake but also mechanically locked after generating a braking force by hydraulic pressure when used as a parking brake. Thus, the present invention relates to a service and parking brake device configured to obtain a braking force.

This type of common and parking brake device is described, for example, in Patent Document 1 below, and in FIG. 4 of Patent Document 1, the cylinder cannot rotate around the cylinder axis and can move in the cylinder axis direction. The piston is assembled to form a hydraulic pressure chamber in the cylinder, and the piston is pushed by the brake fluid supplied to the hydraulic pressure chamber to be engaged with the braked rotating body. An adjustment nut that includes a brake lining that brakes the braked rotating body, and that is assembled to the cylinder so as to be rotatable about the cylinder axis and movable in the cylinder axis direction in the hydraulic chamber, and the adjustment nut Between the cylinder and the adjustment nut in an unlocked state, the adjustment nut can be rotated in the unlocked state. A friction clutch that disables rotation of the adjustment nut in a locked state moved in a predetermined direction, a male screw portion of an adjustment spindle that is provided integrally with the piston, and a male screw portion that is provided integrally with the adjustment nut. And an adjustment timing of the friction clutch can be automatically adjusted by automatically adjusting a distance between the piston and the adjusting nut according to a wear amount of the brake lining. An ordinary and parking brake device comprising an adjusting device and an electromagnetic actuator that is pushed by the piston and is capable of holding the friction clutch in an engaged state in a state where the brake lining brakes the braked rotating body. It is shown.
JP 2000-504811 A

  In the above-mentioned common and parking brake device of Patent Document 1, it is possible to keep the friction clutch in a non-engaged state by turning the electromagnetic actuator in a non-actuated state (non-energized state). It is possible to move the piston connected in the cylinder axial direction through the adjusting nut and the adjusting device. Therefore, at this time, the piston can be advanced and retracted in the cylinder axial direction by supplying and discharging the brake fluid to and from the hydraulic pressure chamber, and the device can be operated as a service brake.

  In addition, the friction clutch can be held in the engaged state by setting the electromagnetic actuator to the operating state (energized state), and the rotation of the adjusting nut is restricted and the adjusting nut is connected to the adjusting device via the adjusting device. It is possible to restrict the movement of the piston in the cylinder axial direction. For this reason, the brake fluid is supplied to the hydraulic chamber, and the piston is moving forward in the cylinder axial direction (braking state in which the brake lining is pushed by the piston and engaged with the braked rotating body). When the electromagnetic actuator is in the activated state and the friction clutch is in the engaged state, the rotation of the adjustment nut is restricted, and the cylinder axial movement of the piston connected to the adjustment nut via the adjustment device is restricted. Thus, even if the brake fluid is discharged from the hydraulic pressure chamber, the braking state can be maintained, and the device can be operated as a parking brake.

  By the way, in the above-mentioned common and parking brake device of Patent Document 1, since the configuration in which the friction clutch, the adjusting device, the electromagnetic actuator and the like are accommodated in the cylinder is employed, there is an advantage that the device can be configured compactly. In addition, the parking brake performance is stable because it has an adjusting device that can automatically adjust the friction clutch operating timing by automatically adjusting the distance between the piston and the adjusting nut according to the amount of wear of the brake lining. However, it is necessary to incorporate an electromagnetic actuator in the hydraulic chamber, the liquid resistance of the electromagnetic coil placed in the brake fluid, and the lead wire led out from the electromagnetic coil in the hydraulic chamber through the cylinder There is a concern about reliability such as sealing performance and heat resistance of the part.

  The present invention has been made to solve the above-mentioned problems while taking advantage of the various advantages described above, and is assembled to a cylinder so as not to rotate around the cylinder axis and to be movable in the cylinder axis direction. A piston that forms a fluid pressure chamber therein, and the piston is pushed by the brake fluid supplied to the fluid pressure chamber to be engaged with the braked rotating body. A brake lining for braking is provided, and the first hydraulic chamber and the second hydraulic chamber are assembled in the hydraulic chamber so as to be rotatable about the cylinder axis and movable in the cylinder axial direction in the hydraulic chamber. A second piston that is partitioned into a pressure chamber; and the second piston is disposed between the second piston and the cylinder, and when the second piston is held at a fixed position, The second piston can be rotated without being engaged with Linda, and when the second piston moves from the home position to the second hydraulic chamber side by a predetermined amount, the second piston is moved with respect to the cylinder. A friction clutch that engages and fixes to make the second piston non-rotatable, a first screw portion that is provided integrally with the piston, and a first screw portion that is provided integrally with the second piston. And a second threaded portion that is screwed together, and an adjustment that can automatically adjust the operation timing of the friction clutch by automatically adjusting the interval between the two pistons according to the amount of wear of the brake lining. And a branching hydraulic circuit that is branched from a hydraulic circuit that can supply and discharge brake fluid to and from the first hydraulic chamber and that can supply and discharge brake fluid to and from the second hydraulic chamber. Communication between one hydraulic chamber and the second hydraulic chamber It is characterized in regular and parking brake system and a switching valve capable of switching the cross.

  In the service and parking brake device according to the present invention, when communication between the first hydraulic pressure chamber and the second hydraulic pressure chamber is ensured by the switching valve, a brake of the same pressure is applied to the first hydraulic pressure chamber and the second hydraulic pressure chamber. When the liquid is supplied under pressure, the second piston does not act on the second piston, and the second piston can be held in a fixed position. As a result, the friction clutch can be held in the non-engaged state, the second piston can be rotated, and the movement of the piston coupled to the second piston via the adjusting device can be performed in the cylinder axial direction. Make it possible. Therefore, at this time, it is possible to move the piston forward and backward in the cylinder axial direction by supplying and discharging brake fluid to and from the hydraulic chambers of the first hydraulic chamber and the second hydraulic chamber. It can be activated.

  Further, when the communication between the first hydraulic pressure chamber and the second hydraulic pressure chamber is blocked by the switching valve, the brake fluid is pressurized and supplied only to the first hydraulic pressure chamber, so that the first hydraulic pressure chamber and the second hydraulic pressure chamber The second piston can be moved from the fixed position to the second hydraulic chamber side by a predetermined amount due to the hydraulic pressure difference between the two hydraulic chambers, and the friction clutch can be engaged. It is possible to restrict the movement of the piston connected to the second piston via the adjusting device and restrict the movement of the piston in the cylinder axial direction.

  For this reason, when the brake fluid is pressurized and supplied to the first hydraulic pressure chamber in a state where the communication between the first hydraulic pressure chamber and the second hydraulic pressure chamber is blocked by the switching valve, the piston moves in the cylinder axial direction. The operation of moving forward and pushing the brake lining and the operation of moving the second piston to the second hydraulic chamber side by a predetermined amount due to the hydraulic pressure difference between the first hydraulic chamber and the second hydraulic chamber are obtained. The brake lining engages with the braked rotating body on the side and the braking operation is obtained, and the friction clutch is engaged on the second piston side to restrict the rotation of the second piston, An operation for restricting the movement of the piston connected to the second piston via the adjusting device in the cylinder axial direction is obtained. Further, in this state, each component member is bent and deformed in accordance with the pressure supply of the brake fluid, and this bending deformation is in a state where it can be reduced / disappeared as the brake fluid is discharged.

  Therefore, in this state, when the brake fluid is depressurized and discharged from the first hydraulic pressure chamber, the adjusting device interposed between the piston and the second piston causes the axial force (cylinder corresponding to the remaining amount of bending deformation) to be applied. The axial compression force) remains and the above-described braking operation can be maintained, and the device can be operated as a parking brake. In order to release the parking brake, the brake fluid is pressurized and supplied to the first hydraulic chamber and the second hydraulic chamber in a state where the first hydraulic chamber and the second hydraulic chamber are communicated by the switching valve. This is done by disengaging the friction clutch and allowing the second piston to rotate. In this state, as the brake fluid is depressurized and discharged from the first hydraulic chamber and the second hydraulic chamber, the second piston rotates and is connected via the adjustment device. The moving piston moves in the cylinder axis direction, and the above-described bending deformation is reduced or eliminated, and the parking brake is released.

  By the way, in the regular and parking brake device according to the present invention, since the configuration in which the friction clutch, the adjusting device and the like are accommodated in the cylinder is adopted, there is an advantage that the device can be configured compactly, and the brake lining wears. Since the adjusting device that can automatically adjust the operation timing of the friction clutch by automatically adjusting the distance between the two pistons according to the amount, the parking brake performance is stable. In addition, since no electrical device is incorporated in the hydraulic chamber in the cylinder, there is no need to worry about the liquid resistance, sealing performance, heat resistance, etc. of the electrical device, and the device can be made highly reliable. Is possible.

  Further, when the release device capable of rotating the second piston by an operation from the outside of the cylinder is assembled to the cylinder in the implementation of the present invention, for example, the malfunction of the switching valve, the hydraulic circuit, the branch hydraulic circuit The second piston can be rotated by the release device when the parking brake is not released due to, for example, a poor pressure supply of brake fluid through the release device. For this reason, it is possible to reduce or eliminate the axial force remaining in the adjusting device, return the piston to the brake release position, and return the second piston to the home position, and release the parking brake accurately. Is possible.

  In implementing the present invention, a reservoir capable of storing brake fluid discharged from the second hydraulic chamber when the communication between the first hydraulic chamber and the second hydraulic chamber is blocked is connected to the switching valve. When the brake fluid is supplied to the first hydraulic pressure chamber in a state where the communication between the first hydraulic pressure chamber and the second hydraulic pressure chamber is blocked by the switching valve, the second piston It is possible to increase the hydraulic pressure difference between the first hydraulic pressure chamber and the second hydraulic pressure chamber acting on the vehicle, and to improve the braking force of the parking brake.

  Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a first embodiment of the present invention. In the first embodiment, a master cylinder MC assisted by a negative pressure booster VB in response to an operation of a brake pedal BP, a skid control, In a brake system having a brake fluid pressure control unit CU capable of traction control, the left and right rear wheels RL and RR employ the common and parking brake device A according to the present invention, and the left and right front wheels FL and FR are ordinary disc brake devices. B is adopted.

  The regular and parking brake device A is a movable caliper type disc brake in which the present invention is implemented. As shown in FIG. 2, the disc rotor 11 (a braked rotating body that rotates integrally with a wheel not shown). An inner pad 13 and an outer pad 14 that clamp and brake the disc from the inside and the outside of the disk rotor 11 are assembled to a mounting 15 that is a support member so as to be slidable along the rotor axial direction. As is well known, the mounting 15 is formed so as to straddle the disk rotor 11, and slides the inner pad 13 along the rotor axial direction at the illustrated inner portion disposed inside the disk rotor 11. The outer pad 14 is slidably supported along the rotor axial direction by an outer portion (not shown) disposed outside the disk rotor 11. Yes.

  The inner pad 13 is composed of a brake lining 13a and a back plate 13b, and can be engaged with and detached from the disc rotor 11 by the brake lining 13a, and can slide on the mounting 15 along the rotor axial direction. The piston 19 assembled to the cylinder portion 17 b of the assembled movable caliper 17 is configured to be pushed toward the disk rotor 11. On the other hand, the outer pad 14 is constituted by a brake lining 14a and a back plate 14b, and can be engaged with and disengaged from the disc rotor 11 by the brake lining 14a. The reaction claw portion 17a of the movable caliper 17 allows the disc rotor to be engaged and disengaged. 11 is configured to be pushed toward the head 11.

  The piston 19 is assembled in an inner hole 17b1 formed in the cylinder portion 17b of the movable caliper 17 so as not to rotate around the cylinder axis via the piston seal 21 and to be movable in the cylinder axis direction (substantially parallel to the rotor axis direction). In addition, a hydraulic chamber Ro filled with brake fluid is formed in the cylinder portion 17b. The hydraulic chamber Ro is connected to a hydraulic circuit 23a that constitutes a part of the brake hydraulic circuit 23 shown in FIG. The piston seal 21 is configured to be deformed toward the rotor side when the piston 19 is pressed toward the disk rotor 11, and has a function of pulling back the piston 19 by returning the deformation when the pressure is released ( Retract function).

  In the first embodiment, the second piston 25, the friction clutch 27, and the adjustment device 29 are incorporated in the cylinder portion 17b of the movable caliper 17, and the release device 31 is assembled. Further, a switching valve 33 is interposed in a branch hydraulic pressure circuit 23b branched from the hydraulic pressure circuit 23a, and a reservoir 35 is connected.

  The second piston 25 can rotate around the cylinder axis through the seal ring 37 and move in the cylinder axis direction through a seal ring 37 in a small diameter portion of a stepped inner hole 17b2 formed in the cylinder portion 17b in the hydraulic chamber Ro. The hydraulic chamber Ro is divided into a first hydraulic chamber R1 and a second hydraulic chamber R2. The first hydraulic chamber R1 is connected to a hydraulic circuit 23a, and brake fluid can be supplied and discharged through the hydraulic circuit 23a. On the other hand, the second hydraulic pressure chamber R2 is connected to the branch hydraulic pressure circuit 23b, and can supply and discharge brake fluid through the branch hydraulic pressure circuit 23b.

  The friction clutch 27 is provided between the second piston 25 and the cylinder portion 17b, and has a tapered friction surface 27a formed on the annular flange portion 25a of the second piston 25, and an annular projecting portion 17b3 of the cylinder portion 17b. A pair of axial bearings 27c, 27d provided with a tapered friction surface 27b that is formed on the friction surface 27a and that can be engaged / separated with the friction surface 27a, and is disposed so as to sandwich the annular flange portion 25a of the second piston 25, A leaf spring 27e or the like is provided between the axial bearing 27d and the cylinder portion 17b and biases the friction surface 27a away from the friction surface 27b.

  In the friction clutch 27, when the second piston 25 is held at a fixed position by the cooperative action of the leaf spring 27e and the bracket 27f, the friction surface 27a is separated from the friction surface 27b. 25 is disengaged from the cylinder portion 17b, and the second piston 25 is rotatable. When the second piston 25 moves from the fixed position to the second hydraulic pressure chamber R2 by a predetermined amount against the action of the leaf spring 27e, the friction surface 27a engages with the friction surface 27b, and the second piston 25 The piston 25 is frictionally fixed to the cylinder portion 17b, and the second piston 25 cannot be rotated.

  The adjusting device 29 can automatically adjust the operation timing of the friction clutch 27 by automatically adjusting the distance between the pistons 19 and 25 according to the wear amount of the brake linings 13a and 14a. The internal thread portion 29a is provided, and the external thread portion 29b is provided integrally with the second piston 25 and screwed and connected to the internal thread portion 29a. In the illustrated female screw portion 29a and male screw portion 29b, the shape of the thread and the thread valley are exaggerated and the screw gap is exaggerated.

  The release device 31 can rotate the second piston 25 by an operation from the outside of the cylinder portion 17b of the movable caliper 17, and includes a hexagonal hole 31a formed in the end axis of the second piston 25, and the hexagonal hole 31a. Is provided with an operation shaft 31c having a hexagonal protrusion 31b that can be engaged and disengaged at the end of the cylinder. The operation shaft 31c is assembled to the cylinder portion 17b via a seal ring 31d so as to be rotatable and movable in the cylinder axis direction, and penetrates the cylinder portion 17b to attach a release lever (not shown). A hexagonal portion 31e is provided at the end outside the cylinder.

  The switching valve 33 is a three-port two-position electromagnetic switching valve whose energization / non-energization is controlled by the electric control unit ECU, and is branched from a hydraulic circuit 23a capable of supplying and discharging brake fluid to and from the first hydraulic chamber R1. A branch hydraulic pressure circuit 23b capable of supplying and discharging brake fluid to and from the second hydraulic pressure chamber R2 is interposed between the first hydraulic pressure chamber R1, the second hydraulic pressure chamber R2, and the reservoir 35. Is possible.

  The reservoir 35 is connected to the switching valve 33 and is discharged from the second hydraulic pressure chamber R2 when the communication between the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 is blocked by the switching valve 33. Brake fluid can be stored. The brake fluid stored in the reservoir 35 is supplied to the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber by the switching valve 33 when no brake fluid is supplied from the brake hydraulic pressure control unit CU to the branch hydraulic pressure circuit 23b. When R2 is communicated, it is configured to be discharged toward the branch hydraulic circuit 23b.

  The brake hydraulic pressure control unit CU is controlled by the electric control unit ECU in a well-known manner when the vehicle is running, and can perform skid control and traction control, and can operate the parking brake switch SW when the vehicle is stopped. The operation of the common and parking brake device A can be controlled by controlling the operation together with the switching valve 33 by the electric control device ECU. The configuration of the brake fluid pressure control unit CU is well known per se, and the description thereof is omitted.

  In the service and parking brake device A of the first embodiment configured as described above, when the parking brake switch SW is OFF and used as a service brake, as shown in FIG. 33 is in a non-energized state, the first hydraulic chamber R1 and the second hydraulic chamber R2 communicate with each other, and the fluid flow from the branch hydraulic circuit 23b to the reservoir 35 is regulated by a check valve incorporated in the switching valve 33. Has been. For this reason, when the brake fluid is pressurized and supplied from the brake fluid pressure control unit CU to the fluid pressure circuit 23a, the brake fluid is pressurized and supplied from the fluid pressure circuit 23a to the first fluid pressure chamber R1, and the fluid pressure circuit. The brake fluid is pressurized and supplied from 23a to the second hydraulic chamber R2 through the branch hydraulic circuit 23b and the switching valve 33.

  By the way, when the communication between the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 is secured by the switching valve 33, the brake fluid of the same pressure is pressurized in the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2. By being supplied, the pushing force due to the hydraulic pressure difference does not act on the second piston 25, and the second piston 25 is held at a fixed position by the cooperative action of the leaf spring 27e of the friction clutch 27 and the bracket 27f. . As a result, the friction clutch 27 is held in the non-engaged state, the second piston 25 can be rotated, and the cylinder of the piston 19 connected to the second piston 25 via the adjusting device 29. Movement in the axial direction is possible. For this reason, at this time, the piston 19 can be advanced and retracted in the cylinder axial direction by supplying and discharging the brake fluid to and from the hydraulic chamber Ro (the first hydraulic chamber R1 and the second hydraulic chamber R2). It is possible to operate the brake device A as a service brake.

  Accordingly, at this time, the brake fluid pressurized and supplied to the first hydraulic chamber R1 causes the piston 19 to be pushed toward the disc rotor 11 in the cylinder axial direction while deforming the piston seal 21 toward the rotor, While pressing the inner pad 13 against the disc rotor 11, the reaction force causes the movable caliper 17 to be pushed toward the inner side, and the reaction claw portion 17 a of the movable caliper 17 presses the outer pad 14 against the disc rotor 11. At this time, the force generated when both pads 13, 14 press the disk rotor 11 is received by the mounting 15 that supports both pads 13, 14, and a braking force that prevents the rotation of the disk rotor 11 is generated. Let In this braking state, the structural member such as the movable caliper 17 is bent and deformed in response to the pressure supply of the brake fluid, and the retracting function can also be obtained by returning the bending deformation of the structural member such as the movable caliper 17 when the brake is released. .

  Further, when the brake fluid pressure supply from the brake fluid pressure control unit CU to the first fluid pressure chamber R1 and the second fluid pressure chamber R2 is removed and the pressure is removed, the above-described deformation of the piston seal 21 returns. The retract function obtained by the above and the retract function obtained by returning the flexural deformation of the constituent members such as the movable caliper 17 cause the piston 19 to move to the inner side, and the movable caliper 17 to move to the outer side. 14 is pushed and pressed against the disk rotor 11. Thereby, the rotational braking of the disk rotor 11 by both the pads 13 and 14 is released.

  When the piston 19 moves forward and backward in the cylinder axial direction, the piston 19 moves forward beyond the screw clearance of the adjusting device 29 (for example, during overpressure braking or when the brake linings 13a and 14a are worn). As shown exaggerated in FIG. 3, after the state (a) is reached, the state (b) is reached, and the internal thread 29a of the adjusting device 29 engages with the external thread 29b to push the external thread 29b toward the rotor. Move. In the state of FIG. 3B, since the second piston 25 is rotatable, when the female screw portion 29a is engaged with the male screw portion 29b and the male screw portion 29b is pushed to the rotor side, the second piston 25 is It rotates in a state where it is held at substantially the same position (fixed position), and advancement beyond the screw clearance of the piston 19 is allowed.

  Further, when the piston 19 moves backward from the state of FIG. 3B beyond the screw clearance of the adjusting device 29 (for example, when the overpressure brake is depressurized), as shown in FIG. Further, the female threaded portion 29a of the adjusting device 29 engages with the male threaded portion 29b to push the male threaded portion 29b to the opposite rotor side. Also at this time, since the second piston 25 is rotatable, when the female screw portion 29a is engaged with the male screw portion 29b and the male screw portion 29b is pushed to the opposite rotor side, the rotation of the second piston 25 causes The second piston 25 rotates while being held at substantially the same position (fixed position), and the piston 19 is allowed to retract beyond the screw gap.

  Further, in the service and parking brake device A of the first embodiment, the parking brake switch SW is turned on when the parking brake switch SW is turned off and is used as a parking brake. The switching valve 33 is energized by the electric control unit ECU between the set time T1 and the set time T1, and the brake is applied between the set time T2 (T1> T2) from the time when the parking brake switch SW is turned ON. The hydraulic control unit CU is brought into a pressurization control state by the electric control unit ECU, and a predetermined amount of brake fluid is pressurized and supplied from the brake hydraulic pressure control unit CU to the dual-use and parking brake device A.

  Therefore, at this time, the state (b) is obtained through the state (a) exaggerated in FIG. 4 during the set time T2 from the time when the parking brake switch SW is turned ON, During the time T1, the state before the state (c) is obtained through the states (a) and (b) of FIG. 4, and further, after the set time T1 has passed, the state of FIG. 4 (c) is obtained. The state shown in FIG. 4D is obtained. The state of FIG. 4A is a state immediately after the parking brake switch SW is turned on. In this state, the switching valve 33 is energized, and the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber. The communication of R2 is blocked, and the brake fluid flows from the second hydraulic chamber R2 into the reservoir 35 and can be stored.

  4B is a state in which the brake fluid is pressurized and supplied to the first hydraulic chamber R1 to obtain a parking brake operation. In this state (pressurized state), the switching valve 33 is The brake fluid is pressurized and supplied only from the brake fluid pressure control unit CU to the first fluid pressure chamber R1, while the brake fluid flows into the reservoir 35 from the second fluid pressure chamber R2. Contained. Further, in this state, the constituent members such as the movable caliper 17 are bent and deformed beyond the screw gap of the adjusting device 29, and the bending deformation is reduced as the brake fluid is discharged.

  Further, the state of FIG. 4C is a state in which the brake fluid pressurized and supplied to the first hydraulic pressure chamber R1 starts to be released and discharged, and in this state (decompression start state), the switching valve 33 is energized. In this state, the brake fluid is discharged from the first fluid pressure chamber R1 to the brake fluid pressure control unit CU through the fluid pressure circuit 23a, and the brake fluid flowing into the reservoir 35 is stored in the reservoir 35. It will be kept. In this state, the bending deformation of the constituent members such as the movable caliper 17 described above is slightly reduced.

  4D is a state in which the pistons 19 and 25 are mechanically locked and the parking brake operation is maintained by the mechanical lock. In this state, the switching valve 33 is in a non-energized state. The first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 communicate with each other, and the release of the brake fluid from the first hydraulic pressure chamber R1 to the brake hydraulic pressure control unit CU is completed, and the reservoir Brake fluid discharge from 35 to the brake fluid pressure control unit CU is also completed. In this state, the bending deformation of the constituent members such as the movable caliper 17 is reduced by the screw gap of the adjusting device 29 but remains.

  By the way, when the state of FIG. 4A shifts to the state of FIG. 4B, the brake fluid is pressurized and supplied only from the brake fluid pressure control unit CU to the first fluid pressure chamber R1. The piston 19 and the movable caliper 17 operate in the same manner as during normal braking, and generate a braking force that prevents the disk rotor 11 from rotating. At this time, the hydraulic pressure is pressurized and supplied only to the first hydraulic chamber R1 while the switching valve 33 is maintained in the energized state, so that the first hydraulic chamber R1 and the second hydraulic chamber R2 are supplied. Due to the hydraulic pressure difference, the second piston 25 moves from the fixed position of FIG. 4A to the second hydraulic pressure chamber R2 side as shown in FIG. 4B, and the friction clutch 27 is engaged. It becomes. For this reason, the rotation of the second piston 25 is restricted, and the axial movement of the piston 19 connected to the second piston 25 via the adjusting device 29 is restricted.

  In the transition from the state of FIG. 4A to the state of FIG. 4B, when the friction clutch 27 is engaged while the piston 19 is moving to the rotor side, the piston 19, the second piston 25 is pulled toward the rotor, and the friction clutch 27 is temporarily disengaged. For this reason, the 2nd piston 25 rotates temporarily and the movement to the rotor side of piston 19 is permitted temporarily. This operation is repeated until the piston 19 finishes moving to the rotor side.

  Accordingly, in a state where the set time T2 has elapsed from the time when the parking brake switch SW is turned on and the piston 19 has finished moving to the rotor side (the state in FIG. 4B), the first hydraulic pressure chamber is thereafter Even if the brake fluid is depressurized and discharged from R1 to the brake fluid pressure control unit CU, the state shown in FIG. 4D is obtained after the state shown in FIG. 4C, and both pistons 19 and 25 are mechanically locked and parked. The brake operation is mechanically maintained. In this state, the adjusting device 29 interposed between the piston 19 and the second piston 25 receives an axial force (compression acting force in the cylinder axis direction) according to the remaining amount of bending deformation of the constituent members such as the movable caliper 17 described above. It is possible to remain and maintain the above-described parking brake operation in a mechanically locked state, and the brake device A is parked even if the switching valve 33 is deenergized as shown in FIG. It can be operated as a brake.

  Further, in the common and parking brake device A of the first embodiment, when the parking brake switch SW is turned off from the state where the parking brake switch SW is turned on and the operation of the parking brake is released, the parking brake switch SW is turned off. The brake fluid pressure control unit CU is controlled by the electric control unit ECU while the switching valve 33 is maintained in a non-energized state for a set time T3 (a time substantially equal to the set time T2) from the time when the brake is applied. A predetermined amount of brake fluid is pressurized and supplied from the hydraulic control unit CU to the dual-use and parking brake device A, and then the brake fluid is discharged under pressure. Therefore, at this time, the state shown in FIG. 4D is changed to the state shown in FIG. 5D through the states shown in FIGS. 5A to 5C, and the parking brake is released.

  5 (a) and 5 (b), the brake fluid is transferred from the brake hydraulic pressure control unit CU to the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 with the switching valve 33 maintained in a non-energized state. Is supplied under pressure. 5C and 5D, the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 are switched from the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 to the brake hydraulic pressure control unit CU while the switching valve 33 is maintained in a non-energized state. The brake fluid is discharged under pressure. In addition, the brake fluid is pressurized and supplied to the second hydraulic pressure chamber R2 during the transition from FIG. 5A to FIG. 5B, and the friction clutch 27 is changed from the engaged state to the disengaged state.

  In the states of FIGS. 5B to 5D, the friction clutch 27 is maintained in the non-engaged state, and the second piston 25 is allowed to rotate, and the first hydraulic chamber R1. The piston 19 can be advanced and retracted in the cylinder axial direction according to the supply and discharge of the brake fluid to the cylinder. 5C and 5D, the second piston 25 rotates as the brake fluid is depressurized and discharged from the first hydraulic chamber R1 and the second hydraulic chamber R2. As a result, the piston 19 connected to the second piston 25 via the adjusting device 29 moves in the cylinder axial direction, and the bending deformation of the constituent members such as the movable caliper 17 is reduced or eliminated, and the parking brake is released. Is done.

  By the way, in the service and parking brake device A of the first embodiment, since the configuration in which the friction clutch 27, the adjusting device 29, and the like are accommodated in the cylinder portion 17b of the movable caliper 17, the device is made compact. There is an advantage that it can be configured, and an adjusting device 29 that can automatically adjust the operation timing of the friction clutch 27 by automatically adjusting the distance between the pistons 19 and 25 according to the wear amount of the brake linings 13a and 14a. Therefore, the parking brake performance is stable. In addition, since no electric device is incorporated in the hydraulic chamber Ro in the cylinder portion 17b of the movable caliper 17, there is no need to worry about the liquid resistance, sealing property, heat resistance, etc. of the electric device, and the device is reliable. Can be high.

  In the service and parking brake device A of the first embodiment, as shown in FIG. 2 and omitted in FIGS. 3 to 5, the second piston 25 is operated by operating the movable caliper 17 from the outside of the cylinder portion 17b. Is attached to the cylinder portion 17b. Therefore, for example, when the parking brake is not released due to a malfunction of the switching valve 33 or a failure in pressurizing and supplying brake fluid through the hydraulic circuit 23a and the branch hydraulic circuit 23b, the release device 31 causes the second piston 25 to be released. Can be rotated. Therefore, the axial force remaining in the adjusting device 29 is reduced / disappeared, the piston 19 is pulled back to the braking release position via the adjusting device 29, and the second piston 25 is returned to the fixed position, so that FIG. It is possible to change from the state of d) to the state of FIG. 5D, and the parking brake can be released accurately.

  In the service and parking brake device A of the first embodiment, the brake is discharged from the second hydraulic chamber R2 when the communication between the first hydraulic chamber R1 and the second hydraulic chamber R2 is interrupted. A reservoir 35 that can store liquid is connected to the switching valve 33. Therefore, when the brake fluid is pressurized and supplied to the first hydraulic pressure chamber R1 in a state where the communication between the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 is blocked by the switching valve 33, The hydraulic pressure difference between the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 acting on the two pistons 25 can be increased, and the braking force of the parking brake can be improved.

  In the first embodiment described above, as shown in FIG. 1, the master cylinder MC assisted by the negative pressure booster VB according to the operation of the brake pedal BP, and the brake hydraulic pressure control capable of skid control and traction control. Although the present invention is implemented in a brake system including a unit CU, a master cylinder MC assisted by a hydraulic booster HB in response to an operation of the brake pedal BP, and a skid, as in the modified embodiment shown in FIG. It is also possible to implement the present invention in a brake system including a brake fluid pressure control unit CU capable of control and traction control.

  Further, in the first embodiment described above, as shown in FIG. 2, the adjusting device 29 is provided integrally with the internal thread portion 29 a provided integrally with the piston 19 and the second piston 25. Although it implemented as a structure provided with the external thread part 29b screwed together with the internal thread part 29a, the adjustment apparatus 29 was integrally provided in the 2nd piston 25 like 2nd Embodiment shown in FIG. It is also possible to implement as a configuration including a female screw portion 29a and a male screw portion 29b provided integrally with the piston 19 and screwed to the female screw portion 29a. In the second embodiment shown in FIG. 7, the operating shaft 31c of the release device 31 is the same as that of the first embodiment shown in FIG. 2 except that the outer end portion has a two-sided width portion 31e. Since it is substantially the same as the configuration, the same reference numerals are given and description thereof is omitted.

  In each of the above-described embodiments, the release device 31 and the reservoir 35 are provided to implement the present invention. However, the present invention can also be implemented without them. In the embodiment in which the reservoir 35 is eliminated, the same function as that of the reservoir 35 is secured by expansion of the pipeline in the branch hydraulic circuit 23b and the switching valve 33 is implemented as a 2-port 2-position electromagnetic on-off valve. Further, in each of the above embodiments, the example in which the present invention is applied to a disk brake (a brake in which the braked rotating body is a disk rotor) has been described, but the present invention is a drum brake (the braked rotating body is a brake drum). The brake) can be changed as appropriate.

  Further, in each of the above-described embodiments, the switching valve 33 is employed so that the first hydraulic chamber R1 and the second hydraulic chamber R2 are communicated when not energized, and the first hydraulic chamber R1 and the second fluid are energized when energized. Although the communication between the pressure chamber R2 is cut off and the second hydraulic pressure chamber R2 and the reservoir 35 are connected, the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 are communicated with each other when energized. The present invention is implemented by adopting a switching valve configured such that communication between the first hydraulic pressure chamber R1 and the second hydraulic pressure chamber R2 is interrupted and the second hydraulic pressure chamber R2 and the reservoir 35 are communicated when energized. It is also possible.

  Further, in each of the above-described embodiments, the seal ring 37 that seals between the cylinder portion 17b and the second piston 25 is provided on the second piston 25, but may be provided on the cylinder portion 17b side. Is possible. Further, in the release device 31, the seal ring 31d that seals between the cylinder portion 17b and the operation shaft 31c is provided on the cylinder portion 17b side, but may be provided on the operation shaft 31c.

It is a whole lineblock diagram showing a 1st embodiment of a brake system containing a service and parking brake device by the present invention. It is a principal part expanded sectional view of the regular and parking brake apparatus shown in FIG. It is operation | movement explanatory drawing when the service and parking brake apparatus shown to FIG. 1 and FIG. 2 operate | moves as a service brake. It is operation | movement explanatory drawing when the regular and parking brake apparatus shown to FIG. 1 and FIG. 2 operate | moves as a parking brake. It is operation | movement explanatory drawing when a parking brake is cancelled | released in the common use parking brake apparatus shown in FIG.1 and FIG.2. It is a whole block diagram which shows other embodiment of the brake system containing the regular and parking brake apparatus by this invention. It is a principal part expanded sectional view which shows 2nd Embodiment of the regular and parking brake apparatus by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Disc rotor, 13, 14 ... Pad, 13a, 14a ... Brake lining, 15 ... Mounting, 17 ... Movable caliper, 17a ... Reaction claw part, 17b ... Cylinder part, 19 ... Piston, 21 ... Piston seal, 23 ... Brake Hydraulic circuit, 23a ... Hydraulic circuit, 23b ... Branch hydraulic circuit, 25 ... Second piston, 27 ... Friction clutch, 29 ... Adjustment device, 29a ... Female screw part, 29b ... Male screw part, 31 ... Release device, 33 ... Switch valve, 35 ... Reservoir, Ro ... Hydraulic chamber, R1 ... First hydraulic chamber, R2 ... Second hydraulic chamber

Claims (3)

A piston that is assembled to the cylinder so that it cannot rotate around the cylinder axis and is movable in the cylinder axis direction, and forms a hydraulic chamber in the cylinder;
The piston is pushed by being pushed by the brake fluid supplied to the hydraulic pressure chamber and engaged with the braked rotating body, and includes a brake lining that brakes the braked rotating body.
A second hydraulic pressure chamber and a second hydraulic pressure chamber, the second hydraulic pressure chamber being divided into a first hydraulic pressure chamber and a second hydraulic pressure chamber that are assembled to the cylinder so as to be rotatable about the cylinder axis and movable in the cylinder axis direction. A piston,
When the second piston is provided between the second piston and the cylinder and is held in place, the second piston can be rotated with the second piston disengaged from the cylinder. Friction that makes the second piston non-rotatable by engaging and fixing the second piston with the cylinder when the second piston moves from the fixed position to the second hydraulic pressure chamber side by a predetermined amount. Clutch,
Wear of the brake lining, comprising: a first screw portion integrally provided on the piston; and a second screw portion integrally provided on the second piston and screwed to the first screw portion. An adjusting device capable of automatically adjusting the operation timing of the friction clutch by automatically adjusting the interval between the pistons according to the amount;
The first hydraulic pressure is branched from a hydraulic circuit capable of supplying and discharging brake fluid to the first hydraulic chamber and interposed in a branched hydraulic pressure circuit capable of supplying and discharging brake fluid to the second hydraulic chamber. A common and parking brake device comprising a switching valve capable of switching between communication and blocking between the chamber and the second hydraulic chamber.   The common and parking brake device according to claim 1, wherein a release device capable of rotating the second piston by an operation from outside the cylinder is assembled to the cylinder. Brake device. 3. The service / parking brake device according to claim 1, wherein when the communication between the first hydraulic pressure chamber and the second hydraulic pressure chamber is blocked, the switching valve is connected to the second hydraulic pressure chamber. A service and parking brake device, wherein a reservoir capable of storing discharged brake fluid is connected.

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