JP2006103353A - Brake device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the relative change of a braking force of the whole vehicle by enabling a reduction of the amount of energy consumption so as to generate an automatic parking brake condition. <P>SOLUTION: A wheel brake 2A equipped with a parking brake mechanism has a parking piston 103 arranged capable of generating the parking brake condition with an advancing motion complying with an increase in the hydraulic pressure in a hydraulic pressure chamber 106 for parking control, and a lock mechanism 105 to lock the parking piston 103 mechanically in the advanced position, being actuated automatically in compliance with the advancing motion of the piston 103, is installed in a casing 102 in a position behind the piston 103, and at the time of automatic parking brake, all wheel brakes 2A are actuated and then a higher hydraulic pressure is allowed to act on the piston 103 as the hydraulic pressure for parking control, and the lock mechanism 105 is actuated to lock the piston 103 in the advanced position. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a first hydraulic pressure source that outputs a hydraulic pressure in response to a brake operation, a second hydraulic pressure source that can output a hydraulic pressure for executing automatic brake control in a non-brake operating state, A wheel brake side hydraulic passage individually connected to a plurality of wheel brakes, and a control valve means capable of controlling the output hydraulic pressure of the first and second hydraulic pressure sources to act on the wheel brake side hydraulic passage. The present invention relates to a vehicle brake device that can obtain an automatic parking brake in a non-brake operation state.

For vehicles in which an automatic parking brake state is obtained by operating the wheel brakes using the output hydraulic pressure of the hydraulic pressure source used for automatic brake control such as vehicle behavior control and traction control during non-brake operation A brake device is known, for example, from US Pat.
Japanese Patent Laid-Open No. 10-76931

  However, as disclosed in Patent Document 1, the automatic parking brake state of all wheel brakes is obtained using the output hydraulic pressure of the hydraulic pressure source that outputs the hydraulic pressure during non-brake operation. As long as the automatic parking brake state continues, the operation of the hydraulic pressure source and the operation of the solenoid valve that controls the output of the hydraulic pressure source will also continue. Problems arise.

  On the other hand, the applicant obtains the automatic parking brake state of some wheel brakes using the output hydraulic pressure of the hydraulic pressure source, and maintains the automatic parking brake state with the hydraulic pressure source stopped operating. As a result, a vehicle brake device has been proposed (Japanese Patent Application No. 2003-34495) that reduces power consumption and simplifies the configuration, and this proposed device is disclosed in Patent Document 1 above. When applied to a vehicle, energy consumption can be reduced by maintaining the parking brake state of some wheel brakes following the brake operation of all wheel brakes using the output hydraulic pressure of the hydraulic pressure source. It will be possible.

  However, if the braking force exerted by the wheel brake is the same in the parking brake state of all the wheel brakes and the parking brake state of some of the wheel brakes thereafter, the braking force of the entire vehicle will change. become.

  The present invention has been made in view of such circumstances, and enables an automatic parking brake state to be obtained by making it possible to reduce energy consumption, and to suppress a relative change in the braking force of the entire vehicle. An object of the present invention is to provide a vehicle brake device.

  In order to achieve the above object, the present invention can output a first hydraulic pressure source that outputs hydraulic pressure in response to a brake operation and a hydraulic pressure for executing automatic brake control in a non-brake operating state. The second hydraulic pressure source, the wheel brake side hydraulic pressure path individually connected to the plurality of wheel brakes, and the output hydraulic pressure of the first and second hydraulic pressure sources are controlled to act on the wheel brake side hydraulic pressure path. And a control valve means that can be used to provide an automatic parking brake in a non-brake operation state, wherein the casing includes a wheel brake equipped with a parking brake mechanism among the plurality of wheel brakes. A parking piston that is slidably fitted so as to be able to obtain an automatic parking brake state by a forward operation according to the action of the control hydraulic pressure, and the parking piston In order to mechanically lock the parking piston in the forward position, the parking piston is automatically locked according to the forward movement of the parking piston and unlocked according to the action of the parking release control hydraulic pressure. A lock mechanism provided in the casing on the side, and a wheel brake side hydraulic pressure passage connected to a wheel brake with a parking brake mechanism, the fluid pressure of the wheel brake side hydraulic passage is changed to the parking control hydraulic pressure and the parking release control. A parking control means connected so as to be able to obtain a hydraulic pressure; a control unit for controlling the operation of the second hydraulic pressure source, the control valve means and the parking control means configured so that the output hydraulic pressure is variable; The control unit controls all the output hydraulic pressure of the second hydraulic pressure source during automatic parking brake. A first step of operating all wheel brakes so as to act on the wheel brake side hydraulic pressure path, and holding the parking piston of the wheel brake with the parking brake mechanism in a reverse position; and a second hydraulic pressure source. In the state where the hydraulic pressure acting on the all-wheel brake side hydraulic pressure path is increased from that in the first step, the hydraulic pressure in the wheel brake side hydraulic path connected to the wheel brake with the parking brake mechanism is used for releasing the parking. A second step of causing the lock mechanism to act as a control fluid pressure and a force to act on the parking piston as the parking control fluid pressure; and a second step with the parking control fluid pressure acting on the parking piston. Stop the operation of the hydraulic pressure source and release the control hydraulic pressure for parking release These steps are sequentially executed.

  According to such a configuration of the invention, in the first step, all the wheel brakes are braked using the output hydraulic pressure of the second hydraulic pressure source, and in the second step, the fluid in the wheel brake side hydraulic pressure path is braked. Since the parking piston of the wheel brake with parking brake mechanism moves forward by causing the pressure to act as the control fluid pressure for parking, the lock mechanism mechanically locks the advance position of the parking piston in the third step. It is necessary to continue the operation of the pressure source until the second step. In the third step, the lock mechanism mechanically locks the advance position of the parking piston and maintains the parking brake state. The control hydraulic pressure and the parking release control hydraulic pressure are also unnecessary, and the operation of the electromagnetic valve for controlling the hydraulic pressure is also unnecessary. Therefore, the automatic parking brake state can be obtained with a simple structure with reduced energy consumption. Moreover, the parking of the wheel brake with the parking brake mechanism is more effective when only the wheel brake with the parking brake mechanism is operated than the hydraulic pressure acting on each wheel brake when the brakes of all the wheels are operating. Since the hydraulic pressure acting on the piston is high, the relative change in the braking force of the entire vehicle can be kept small even if the number of wheel brakes that are braked decreases.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 4 show a first embodiment of the present invention. FIG. 1 is a hydraulic circuit diagram of a vehicle brake device, FIG. 2 is a longitudinal sectional view of a disc brake during non-parking brake, and FIG. FIG. 4 is a block diagram showing a configuration of a control system related to an automatic parking brake of the left front wheel brake.

  First, in FIG. 1, a tandem master cylinder M, which is a first hydraulic pressure source, generates first and second output ports 1A, 1B that generate a brake hydraulic pressure in accordance with a pedaling force applied to a brake pedal P by a vehicle driver. The first output port 1A is connected to the first output hydraulic pressure path 3A, and the second output port 1B is connected to the second output hydraulic pressure path 3B.

  The first output hydraulic pressure path 3A is connected to the hydraulic pressure source hydraulic pressure path 20A via a pressure regulating valve 17A which is a normally open type linear solenoid valve, and the second output hydraulic pressure path 3B is a normally open type linear solenoid. It is connected to a hydraulic pressure source hydraulic pressure path 20B via a pressure regulating valve 17B that is a valve.

  The hydraulic pressure source hydraulic pressure path 20A is connected to the wheel brake side hydraulic pressure path 4A connected to the left front wheel brake 2A, which is a disc brake, via an inlet valve 6A, which is a normally open solenoid valve. It is connected to a wheel brake side hydraulic pressure passage 4B connected to a certain right rear wheel brake 2B via an inlet valve 6B which is a normally open solenoid valve. Further, the hydraulic pressure source hydraulic pressure path 20B is connected to the wheel brake side hydraulic pressure path 4C connected to the right front wheel brake 2C via an inlet valve 6C which is a normally open solenoid valve, and is also a disc brake. The wheel brake side hydraulic pressure passage 4D connected to the wheel brake 2D is connected via an inlet valve 6D which is a normally open solenoid valve. Further, check valves 7A to 7D are connected in parallel to the inlet valves 6A to 6D, respectively.

  Between the first reservoir 8A corresponding to the first output hydraulic pressure path 3A and the wheel brake side hydraulic pressure paths 4A, 4B, outlet valves 9A, 9B, which are normally closed solenoid valves, are respectively provided, and the second output hydraulic pressure path Outlet valves 9C and 9D, which are normally closed solenoid valves, are provided between the second reservoir 8B corresponding to 3B and the wheel brake side hydraulic pressure paths 4C and 4D, respectively.

  Thus, the inlet valve 6A, the check valve 7A and the outlet valve 9A, and the inlet valve 6B, the check valve 7B and the outlet valve 9B apply the hydraulic pressure of the hydraulic pressure source hydraulic pressure path 20A to the wheel brake side hydraulic pressure paths 4A and 4B. The control valve means VA, VB which can be controlled and acted are configured, and the inlet valve 6C, the check valve 7C and the outlet valve 9C, and the inlet valve 6D, the check valve 7D and the outlet valve 9D are provided with the wheel brake side hydraulic pressure passage 4C, Control valve means VC and VD that can act by controlling the hydraulic pressure of the hydraulic pressure source hydraulic path 20B to 4D are configured.

  The first and second reservoirs 8A and 8B are unidirectional to allow the brake fluid to flow to the pumps 10A and 10B on the suction side of the first and second pumps 10A and 10B driven by the common electric motor 11. The hydraulic pressure source hydraulic pressure paths 20A and 20B are connected to the first and second pumps 10A and 10B via the suction valves 18A and 18B, which are normally closed solenoid valves. It is connected between the direction valves 19A and 19B, and is connected to the discharge side of the first and second pumps 10A and 10B via the first and second dampers 13A and 13B.

  Thus, by operating the electric motor 11 with the suction valves 18A and 18B excited and opened, the first and second pumps 10A and 10B receive the brake fluid sucked and pressurized from the master cylinder M side. The fluid is discharged into the fluid pressure source fluid pressure paths 20A and 20B. At this time, the pressure regulating valves 17A and 17B are controlled according to the brake fluid pressure detected by the pressure sensors 15A and 15B provided in the wheel brake side fluid pressure passages 4A and 4C connected to the left front wheel and right front wheel brakes 2A and 2C. By controlling the operation, the hydraulic pressure of the hydraulic pressure source hydraulic paths 20A and 20B can be made constant.

  That is, the pumps 10A, 10B and the pressure regulating valves 17A, 17B constitute second hydraulic pressure sources 5A, 5B that output hydraulic pressure to the hydraulic pressure source hydraulic pressure paths 20A, 20B during non-braking operation. By controlling the constant hydraulic pressures of the source hydraulic pressure paths 20A and 20B with the control valve means VA to VC, different brake hydraulic pressures can be applied to the wheel brakes 2A to 2D, respectively. Automatic brake control such as behavior stability control and traction control can be executed. In addition, the hydraulic pressures of the hydraulic pressure source hydraulic paths 20A and 20B can be changed to high and low by the pressure regulating valves 17A and 17B.

  When the brake is operated, the pressure regulating valves 17A and 17B are demagnetized and opened, and the suction valves 18A and 18B are demagnetized and closed. When there is no possibility that the wheels are locked, the control valve means VA˜ The inlet valves 6A to 6D of the VD are demagnetized and opened, and the outlet valves 9A to 9D are demagnetized and closed. The brake hydraulic pressure output from the first output port 1A of the master cylinder M is the inlet valve. It acts on the left front wheel and right rear wheel brakes 2A and 2B via 6A and 6B. The brake hydraulic pressure output from the second output port 1B of the master cylinder M acts on the right front wheel brakes 2C and 2D via the inlet valves 6C and 6D.

  When the wheel is about to enter the locked state during the braking, the inlet valve corresponding to the wheel that is about to enter the locked state among the inlet valves 6A to 6D is excited and closed, and the outlet valves 9A to 9D. Of these, the outlet valve corresponding to the wheel is excited and opened. Thereby, a part of the brake fluid pressure of the wheel that is about to enter the locked state is absorbed by the first reservoir 8A or the second reservoir 8B, and the brake fluid pressure of the wheel that is about to enter the locked state is reduced. It will be.

  Further, when the brake fluid pressure is kept constant, the inlet valves 6A to 6D are excited and closed, and the outlet valves 9A to 9D are demagnetized and closed, and when the brake fluid pressure is further increased. For example, the inlet valves 6A to 6D may be demagnetized and opened, and the outlet valves 9A to 9D may be demagnetized and closed.

  By controlling the demagnetization / excitation of the inlet valves 6A to 6D and the outlet valves 9A to 9D in this way, braking can be efficiently performed without locking the wheels.

  Thus, during the antilock brake control as described above, the electric motor 11 rotates and the first and second pumps 10A and 10B are driven in accordance with the operation of the electric motor 11. Therefore, the first and second pumps are driven. The brake fluid absorbed in the two reservoirs 8A and 8B is sucked into the first and second pumps 10A and 10B, and then the first and second dampers 13A and 13B, the hydraulic pressure source hydraulic pressure paths 20A and 20B, and the pressure regulating valve 17A. , 17B and then returned to the first and second output hydraulic pressure passages 3A, 3B. Such recirculation of the brake fluid can prevent an increase in the amount of depression of the brake pedal P due to the absorption of the brake fluid in the first and second reservoirs 8A and 8B. In addition, the pulsation of the discharge pressures of the first and second pumps 10A and 10B is suppressed by the action of the first and second dampers 13A and 13B, and the operation feeling of the brake pedal P is not hindered by the reflux.

  In FIG. 2, in the left front wheel brake 2 </ b> A that is a disc brake with a parking brake mechanism, a first friction pad 72 and a second friction pad 73 are arranged opposite to each other of a brake disc 71 that rotates with the wheel. These first and second friction pads 72 and 73 are composed of linings 72a and 73a that can be brought into contact with the brake disc 71, and back plates 72b and 73b fixed to the back surfaces of the linings 72a and 73a. The back plates 72b and 73b are supported by a bracket 74 fixed to the vehicle body so as to be movable in the axial direction of the brake piston 78. A brake caliper 75 straddling the first and second friction pads 72 and 73 is supported on the bracket 74 so as to be movable in the axial direction of the brake piston 78.

  The brake caliper 75 includes a first sandwiching arm 75a facing the back plate 72b of the first friction pad 72 and a second sandwiching arm 75b facing the back plate 73b of the second friction pad 73. The second sandwiching arms 75 a and 75 b are integrally connected by a bridging portion 75 c that passes through the outer periphery of the brake disc 71. The first pinching arm 75 a is provided with a cylinder hole 76, and a cup-shaped brake piston 78 is slidably fitted into the cylinder hole 76 via a seal member 77. The front end of the brake piston 78 facing the back plate 72b of the first friction pad 72 is connected to the open end of the cylinder hole 76 by a bellows-like dust cover 79, and the brake facing the back of the brake piston 78 A hydraulic pressure chamber 80 is formed in the first pinching arm 75a, and the brake hydraulic pressure chamber 80 is connected to the wheel brake side hydraulic pressure path 4A via a port 81 provided in the first pinching arm 75a.

  An adjusting mechanism 82 is provided in the first pinching arm 75a of the brake caliper 75, and this adjusting mechanism 82 is connected to the brake piston 78 so as not to be relatively rotatable and is accommodated in the brake hydraulic pressure chamber 80. An adjusting nut 83, an adjusting bolt 84 whose front end is screwed to the adjusting nut 83, and a rear portion of the brake fluid pressure chamber 80, and capable of moving in the axial direction while preventing rotation around the axis. A relay piston 85 that is liquid-tightly and slidably fitted to the brake caliper 75, and is integrally and coaxially connected to the rear portion of the adjustment bolt 84 so as to be liquid-tight and slidable to the relay piston 85. A small piston 86 that is fitted and elastically biased in a direction to frictionally engage with the relay piston 85.

  A relay cylinder hole 87 having a diameter smaller than that of the cylinder hole 76 is coaxially provided at an end of the first clip arm 75a of the brake caliper 75 opposite to the brake disc 71, and a rear portion of the stepped relay piston 85 is provided. The front part is inserted into the rear part of the cylinder hole 76 and is slidably fitted into the relay cylinder hole 87 via the seal member 88. Moreover, the brake caliper 75 and the relay piston 85 are fitted with both ends of a regulation pin 89 that has an axis parallel to the cylinder hole 76 and the relay cylinder hole 87 and is disposed at a position offset from the axis of the cylinder hole 76. The As a result, the relay piston 85 is prevented from rotating around an axis that is coaxial with the cylinder hole 76 and the relay cylinder hole 87 and can be moved along the axis to be supported by the brake caliper 75. .

  The relay piston 85 is coaxially provided with a small cylinder hole 91 having a tapered clutch surface 90 at the front end opening. On the other hand, at the rear part of the adjusting bolt 84, a movable clutch body 92 that can be frictionally engaged with the clutch surface 90 and a small piston 86 that fits in the small cylinder hole 91 in a liquid-tight and slidable manner are coaxial. And it is connected continuously.

  A retainer 95 engaged and supported by a clip 94 mounted on the inner surface of the cylinder hole 76 has one end of a clutch spring 93 that exerts a spring force that frictionally engages the movable clutch body 92 with the clutch surface 90 of the relay piston 85. The other end of the clutch spring 93 comes into contact with the movable clutch body 92 via a ball bearing 96.

  The adjustment nut 83 and the adjustment bolt 84 are engaged with each other by a quick screw 97 having a plurality of threads and a groove having a coarse pitch. One end of an over-adjustment prevention spring 98 that exerts a spring force that urges the adjustment nut 83 toward the brake piston 78 is brought into contact with the adjustment nut 83 and is engaged and supported by a clip 99 mounted on the inner surface of the brake piston 78. The other end of the over-adjustment prevention spring 98 is brought into contact with and supported by the retainer 100.

  The adjustment nut 83 and the brake piston 78 cannot be rotated relative to each other due to the concave-convex engagement of the contact portions, and the back plate 72b of the first friction pad 72 and the brake piston 78 cannot be rotated relative to each other due to the concave-convex engagement. It is.

  In such an adjustment mechanism 82, when hydraulic pressure is supplied to the brake hydraulic pressure chamber 80 during normal braking, the brake piston 78 that receives the hydraulic pressure elastically deforms the seal member 77 in the cylinder hole 76 in FIG. When the first friction pad 72 is pressed against one side of the brake disk 71, the brake caliper 75 moves to the right in the direction opposite to the moving direction of the brake piston 78, and the second pinching arm 75b moves. The second friction pad 73 is pressed against the other side of the brake disc 71. As a result, the first and second friction pads 72 and 73 come into contact with both surfaces of the brake disc 71 with an equal surface pressure, and a braking force for braking the wheel is generated.

  During the braking, the hydraulic pressure supplied to the brake hydraulic pressure chamber 80 does not cause the adjustment nut 83 to generate an axial load, but the movable clutch body 92 integrated with the adjustment bolt 84 meshing with the adjustment nut 83. In this case, a rightward load having a magnitude obtained by multiplying the cross-sectional area of the small piston 86 by the hydraulic pressure is generated, and a frictional engagement force corresponding to the load acts between the movable clutch body 92 and the clutch surface 90 of the relay piston 85. To do.

  Incidentally, since the hydraulic pressure acting on the brake hydraulic pressure chamber 80 during normal braking is relatively low, the frictional engagement force acting between the movable clutch body 92 and the relay piston 85 is also relatively small. Therefore, when the brake piston 78 moves forward with the progress of wear of the linings 72 a and 73 a of the first and second friction pads 72 and 73, the adjustment nut 83 moves forward together with the brake piston 78 by the elastic force of the over-adjustment prevention spring 98. Then, the movable clutch body 92 integrated with the adjustment bolt 84 meshing with the adjustment nut 83 is separated from the clutch surface 90 of the relay piston 85 against the hydraulic pressure acting on the brake hydraulic pressure chamber 80 and the elastic force of the clutch spring 93. It is.

  When the movable clutch body 92 is separated from the clutch surface 90 of the relay piston 85, the adjustment bolt 84 urged to the right by the hydraulic pressure acting on the movable clutch body 92 and the elastic force of the clutch spring 93 becomes an unrotatable adjustment nut. While moving in the fast screw 97 relative to 83, the movable clutch body 92 moves to the right while being relatively rotated, and the clutch surface 90 of the relay piston 85 is engaged again. At this time, the movable clutch body 92 can be smoothly rotated by the action of the ball bearing 96 arranged between the clutch spring 93.

  In this way, as the wear of the linings 72a and 73a in the first and second friction pads 72 and 73 progresses, the adjustment nut 83 moves relative to the left side with respect to the adjustment bolt 84 so as to compensate for the amount of wear. Therefore, the clearance between the linings 72a and 73a of the first and second friction pads 72 and 73 and the brake disk 71 during non-braking can be automatically maintained constant.

  When the hydraulic pressure acting on the brake hydraulic pressure chamber 80 is reduced to release the brake state, the brake piston 78 moves backward due to the deformation restoring force of the seal member 77, but the reverse force is transmitted via the adjustment nut 83 and the adjustment bolt 84. Since the movable clutch body 92 is engaged with the clutch surface 90 of the relay piston 85, the relative rotation of the adjustment bolt 84 with respect to the adjustment nut 83 is restricted. Therefore, the brake piston 78 can only move backward by a stroke corresponding to the backlash between the adjusting nut 83 and the adjusting bolt 84, and the backlash is between the first and second friction pads 72 and 73 and the brake disk 71. Proper clearance of minutes is given.

  When strong braking is performed, the automatic adjustment is performed until the hydraulic pressure in the brake hydraulic pressure chamber 80 rises to a predetermined value that causes the brake caliper 75 to deform, and the hydraulic pressure reaches the predetermined value. When exceeding, the movable clutch body 92 is strongly pressed against the clutch surface 90 of the relay piston 85 by hydraulic pressure, so that the movable clutch body 92 and the relay piston 85 are coupled so as not to be relatively rotatable. As a result, the adjustment bolt 84 is restrained to be non-rotatable and the adjustment nut 83 that is originally non-rotatable remains on the adjustment bolt 84. Therefore, when the brake piston 78 further moves forward due to elastic deformation of the brake caliper 75 due to hydraulic pressure, While compressing the adjustment prevention spring 98, only the brake piston 78 moves forward leaving the adjustment nut 83. In this way, over-adjustment between the adjusting nut 83 and the adjusting bolt 84 when strong braking is performed is prevented.

  Referring also to FIG. 3, a casing 102 extending on the opposite side to the brake disc 71 is integrally connected to the first sandwiching arm 75 a of the brake caliper 75 and abuts against the relay piston 85 from the rear side. The parking piston 103 is slidably fitted to the casing 102.

  The casing 102 forms a sliding hole 101 that is coaxial with the cylinder hole 76 of the brake caliper 75, and a parking brake state can be obtained by a forward operation according to the action of the control fluid pressure for parking on the back surface. The parking piston 103 is slidably fitted into the sliding hole 101 so as to contact the relay piston 85 from the rear, and the parking piston 103 is mechanically locked in the forward position. A lock mechanism 105 that automatically locks in accordance with the forward operation and unlocks in response to the action of the parking release control hydraulic pressure is provided in the casing 102 on the rear side of the parking piston 103.

  The sliding hole 101 has a diameter larger than that of the relay cylinder hole 87 and is connected to the rear end of the relay cylinder hole 87 coaxially with the parking piston front sliding hole 101a and the parking piston front sliding hole 101a. The parking piston rear sliding hole portion 101b is coaxially connected to the rear end of the parking piston front sliding hole portion 101a, and the parking piston rear sliding hole portion 101b is smaller in diameter than the parking piston rear sliding hole portion 101b. The lock piston front sliding hole portion 101c coaxially connected to the rear end of the sliding hole portion 101b and the lock piston front sliding hole portion 101c are formed to have a larger diameter than the lock piston front sliding hole portion 101c. The rear end of the lock piston is coaxially connected to the rear slide hole portion 101d of the lock piston, and the rear end of the lock piston rear slide hole portion 101d is the casing 102. It closed at the rear end wall 102a.

  An annular step 101e facing forward is formed on the inner surface of the casing 102 between the parking piston front sliding hole 101a and the parking piston rear sliding hole 101b, and the parking piston rear sliding hole 101a and the lock piston front An annular locking step 101f facing forward is formed on the inner surface of the casing 102 between the inner sliding holes 101c, and the casing is further formed between the locking piston front sliding hole 101c and the locking piston rear sliding hole 101d. An annular step portion 101g facing rearward is formed on the inner surface of 102.

  The parking piston 103 is formed by forming a large-diameter portion 103a slidably fitted in the parking piston front sliding hole portion 101a and an annular step portion 103c facing the rear, and the large-diameter portion 103a. It has a small diameter portion 103b that is coaxially connected to the rear portion of the diameter portion 103a and is slidably fitted in the rear sliding hole 101b of the parking piston. A pressing rod 103d for pressing from the side is integrally and coaxially connected.

  An annular parking control hydraulic pressure chamber 106 is formed between the casing 102 and the parking piston 103 between the step 103 c of the parking piston 103 and the step 101 e of the casing 102. Annular seal members 107 and 108 for sealing from both sides are mounted on the outer surfaces of the large diameter portion 103a and the small diameter portion 103b of the parking piston 103. In addition, the pressure receiving area of the parking piston 103 facing the parking control hydraulic pressure chamber 106 is set larger than the pressure receiving area of the small piston 86 facing the brake hydraulic pressure chamber 80.

  The lock mechanism 105 is slidably fitted to the casing 102 on the rear side of the parking piston 103 so that a forward biasing force is applied when the parking piston 103 moves forward, and the parking release control pressure is set. Lock piston 104 that can be operated rearward, a cylindrical holding cylinder 51 integrally and coaxially connected to the rear portion of the parking piston 103, and a plurality of circumferential positions of the holding cylinder 51. The spheres 52, 52... That are held to be movable in the radial direction of the holding cylinder, and inserted into the holding cylinder 51 so as to be relatively movable in the axial direction, and the holding cylinders 51 are inserted into the spheres 52, 52. And an insertion shaft 53 integrally connected to the front end of the lock piston 104 so as to come into contact with the inner side.

  The lock piston 104 is formed with a small diameter portion 104a formed between a small diameter portion 104a slidably fitted into the lock piston front sliding hole portion 101c and a rear portion of the small diameter portion 104a. A large-diameter portion 104b that is coaxially connected to the rear portion of the portion 104a and that is slidably fitted into the rear sliding hole portion 101d of the lock piston is integrally provided.

  An annular parking release control hydraulic pressure chamber 109 is formed between the lock piston 104 and the casing 102 between the step 104c of the lock piston 104 and the step 101f of the casing 102, and the rear end wall 102a of the casing 102 and the lock piston. A spring chamber 110 is formed between 104, and an open chamber 111 opened to the outside is formed in the casing 102 between the parking piston 103 and the lock piston 104.

  Thus, on the outer surface of the small diameter portion 104 a of the lock piston 104, an annular seal member 112 that seals between the parking release control hydraulic pressure chamber 109 and the open chamber 111 is mounted, and the outer surface of the large diameter portion 104 b of the lock piston 104. Is attached with an annular seal member 113 for sealing between the parking release control hydraulic pressure chamber 109 and the spring chamber 110.

  A spring 114 is contracted between the rear end wall 102a and the lock piston 104, and the lock piston 104 is elastically biased toward the front side by the spring force of the spring 114. Moreover, the spring load of the spring 114 is set smaller than the spring load of the clutch spring 93 in the adjustment mechanism 82.

  .. Are provided at a plurality of positions spaced apart in the circumferential direction of the holding cylinder 51, and the spheres 52, 52... Are inserted and held in the holding holes 54, 54. Further, the insertion shaft 53 is configured so that each of the spheres 52, 52... Can be brought into rolling contact with the lock piston front sliding hole portion 101c in a state where the parking piston 103 is in the retreat limit as shown in FIG. When the parking piston 103 moves forward from the retreat limit and the lock piston 104 moves forward, the spheres 52, 52... The large-diameter shaft portion 53b on the rear side coaxially connected to the small-diameter shaft portion 53a can be pushed up to the outer side along the radial direction of the holding cylinder 51 so as to come into contact with the 101b. A portion is coaxially and integrally connected through a tapered step portion 53c that can change the location between the small diameter shaft portion 53a and the large diameter shaft portion 53b. It is intended.

  According to such a lock mechanism 105, when the parking piston 103 moves forward, the lock piston 104 moves forward by the spring force of the spring 114, so that the large-diameter shaft portion 53 b of the insertion shaft 53 at the front end of the lock piston 104 moves. Each of the pushed up spheres 52, 52... Engages with the engaging step portion 101f of the casing 102, thereby preventing the parking piston 103 from retreating and obtaining a parking brake state. By applying pressure to the lock piston 104 to retract the lock piston 104, the parking brake state can be released.

  The wheel brake side hydraulic pressure path 4A communicating with the brake hydraulic pressure chamber 80 and the parking release control hydraulic pressure chamber 109 are connected to each other via a communication path 115, and the wheel brake side hydraulic pressure path 4A is normally closed. It is connected to the parking control hydraulic pressure chamber 106 via the electromagnetic valve 66A.

  The normally closed electromagnetic valve 66A and the communication passage 115 constitute a parking control means 67A that can obtain the hydraulic pressure of the wheel brake side hydraulic pressure passage 4A as the parking control hydraulic pressure and the parking release control hydraulic pressure. When the normally closed electromagnetic valve 66A is opened, the hydraulic pressure in the wheel brake side hydraulic pressure passage 4A can be applied to the parking control hydraulic pressure chamber 106 as the parking control hydraulic pressure, and the wheel brake can be applied. When the hydraulic pressure is generated in the side hydraulic pressure path 4A, the hydraulic pressure in the wheel brake side hydraulic pressure path 4A acts on the parking release control hydraulic pressure chamber 109 as the parking release control hydraulic pressure.

  By the way, in obtaining the automatic parking brake state of the left front wheel brake 2A, as shown in FIG. 4, the second hydraulic pressure source 5A is configured together with the electric motor 11 for driving the first pump 10A and the first pump 10A. The control unit C controls the operation of the pressure regulating valve 17A, the suction valve 18A, the inlet valve 6A and the outlet valve 9A of the control valve means VA, and the normally closed electromagnetic valve 66A constituting a part of the parking control means 67A.

  The right front wheel brake 2C is configured with a parking brake mechanism in the same manner as the left front wheel brake 2A described above. When the automatic front brake state of the right front wheel brake 2C is obtained, the left front wheel brake 2A As in the case of the above, the electric motor 11, the pressure regulating valve 17B, the suction valve 18B, the control valve means VC and the parking control means which constitute the second hydraulic pressure source 5B together with the second pump 10B driven by the electric motor 11. The operation of the normally closed electromagnetic valve 66B constituting a part of 67B may be controlled by the control unit C.

  Thus, when the automatic parking brake state is obtained, the control unit C sequentially executes the following first to third steps. First, in the first step, the second hydraulic pressure sources 5A and 5B are used. The pressure control valves 17A and 17B adjust the hydraulic pressures of the hydraulic pressure source hydraulic paths 20A and 20B, which are the output hydraulic pressures, to the same hydraulic pressure as in, for example, automatic brake control such as vehicle behavior stability control and traction control. All the wheel brakes 2A to 2D are braked so that the hydraulic pressures of the hydraulic pressure source hydraulic paths 20A and 20B are applied to the wheel brake side hydraulic pressure paths 4A to 4D, and the wheels for the left and right front wheels are operated. The parking pistons 103 of the brakes 2A and 2c are held at the retracted position. That is, the control unit C excites and opens the suction valves 18A and 18B with the normally closed solenoid valves 66A and 66B of the parking control means 67A and 67B closed, and the electric motor 11 causes the first and second pumps 10A to be opened. , 10B and controlling the operation of the pressure regulating valves 17A, 17B to demagnetize the inlet valves 6A-6D of the control valve means VA-VD while maintaining the fluid pressure in the fluid pressure source fluid pressure paths 20A, 20B constant. By maintaining the valve open, the hydraulic pressure of the hydraulic pressure source hydraulic pressure paths 20A and 20B is applied to the wheel side brake hydraulic pressure paths 4A to 4D. As a result, the constant hydraulic pressure output from the second hydraulic pressure sources 5A and 5B is applied to the brake hydraulic pressure chambers 80 of the all-wheel brakes 2A to 2D, and the parking release control fluid for the left and right wheel brakes 2A and 2C. The brake piston 78 is advanced by the all-wheel brakes 2A to 2D while suppressing the forward movement of the lock piston 104 in the left and right wheel brakes 2A and 2C.

  In the next second step, the control unit C increases the hydraulic pressure acting on the all-wheel brake side hydraulic pressure paths 4A to 4D from the second hydraulic pressure sources 5A and 5B as compared with the first step. In this state, the hydraulic pressure of the wheel brake side hydraulic passages 4A, 4C connected to the left and right front wheel brakes 2A, 2C is applied to the lock mechanism 105 as a parking release control hydraulic pressure, and the parking piston 103 is used as a parking control hydraulic pressure. To act on. That is, the control unit C uses the pressure regulating valves 17A and 17B to change the hydraulic pressure of the hydraulic pressure source hydraulic pressure paths 20A and 20B at the time of the automatic braking control such as the hydraulic pressure at the first step, for example, vehicle behavior stability control or traction control. Wheel pressure is increased by applying the increased hydraulic pressure to all the wheel brakes 2A to 2D, and opening the normally closed solenoid valves 66A and 66B of the parking control means 67A and 67B. The parking piston 103 is moved forward by applying the hydraulic pressure in the hydraulic pressure paths 4A and 4C to the control hydraulic pressure chamber 106 for parking.

  In the subsequent third step, the control unit C stops the operation of the second hydraulic pressure sources 5A and 5B while applying the parking control hydraulic pressure to the parking piston 103, and sets the parking release control hydraulic pressure. release. That is, the control unit C stops driving the first and second pumps 10A and 10B by the electric motor 11, demagnetizes and opens the pressure regulating valves 17A and 17B, and demagnetizes and closes the suction valves 18A and 18B. The closed electromagnetic valves 66A and 66B are demagnetized and returned to the closed state. Then, the fluid pressure in the parking control fluid pressure chamber 106 is locked while being high, the fluid pressure in the parking fluid control chamber 109 is released, the lock piston 104 is moved forward by the spring force of the spring 114, and the parking piston. In accordance with the forward movement of the lock piston 104 and the lock piston 104, the lock mechanism 105 performs the lock operation so that the spherical bodies 52, 52.

  When the parking piston 103 is thus locked by its forward operation, the relay piston 85 is advanced by the pressing rod 103d of the parking piston 103, and the movement of the relay piston 85 is caused by the movable clutch body 92, the adjusting bolt 84, and The brake piston 78 is advanced via the adjusting nut 83, and the linings 72a and 73a of the first and second friction pads 72 and 73 are pressed against both surfaces of the brake disc 71 in the same manner as in normal braking to generate a braking force. Thus, the parking brake state can be obtained.

  In the process of obtaining the parking brake state, the relay piston 85 and the movable clutch body 92 are frictionally engaged with each other by the pressing force of the parking piston 103 so that they cannot be rotated relative to each other, so that the relative rotation of the adjusting bolt 84 and the adjusting nut 83 is restricted. Therefore, when the left front wheel brake 2A functions as a parking brake, the automatic adjustment by the adjustment mechanism 82 is not performed.

  When releasing the parking brake state, the suction valves 18A and 18B are excited and opened, the first and second pumps 10A and 10B are driven by the electric motor 11, and the operation of the pressure regulating valves 17A and 17B is controlled to control the hydraulic pressure. The hydraulic pressure of the hydraulic pressure source hydraulic pressure paths 20A and 20B is applied to the wheel side brake hydraulic pressure paths 4A to 4D in a state where the hydraulic pressure of the source hydraulic pressure paths 20A and 20B is kept constant, and the normally closed solenoid valve 66A, 66B is excited and opened. As a result, the hydraulic pressures in the brake hydraulic pressure chamber 80, the parking control hydraulic pressure chamber 106, and the parking release control hydraulic pressure chamber 109 increase simultaneously. In the pressure increasing process, first, the hydraulic pressure larger than the spring force of the spring 114 is obtained. Acts on the lock piston 104 so that the lock piston 104 moves backward, and then acts on the small piston 86 rather than the forward pressing force acting on the parking piston 103 by the hydraulic pressure of the parking control hydraulic chamber 106. The hydraulic pressure in the reverse direction and the resultant force of the clutch spring 93 increase and the parking piston 103 moves backward. As a result, the lock mechanism 105 is unlocked and the parking brake state is released.

  Next, the operation of the first embodiment will be described. When the parking brake is automatically operated for the left and right front wheel brakes 2A, 2C, the casing 102 provided in the left and right front wheel brakes 2A, 2C includes: The parking piston 103 that allows the left and right front wheel brakes 2A and 2C to obtain the automatic parking brake state by sliding forward according to the increase in the hydraulic pressure of the parking control hydraulic chamber 106 facing the back surface slides. A wheel brake that can be fitted and is automatically locked according to the forward movement of the parking piston 103 to mechanically lock the parking piston 103 in the forward position, and is connected to the left and right front wheel brakes 2A and 2C. A lock mechanism 10 that unlocks according to the hydraulic pressure action of the side hydraulic pressure paths 4A and 4C. There is provided in the casing 102 in a rear side of the parking piston 103, the wheel brake side hydraulic pressure passage 4A, 4C and between the parking control fluid pressure chamber 106 normally closed solenoid valve 66A, 66B is interposed.

  According to such a configuration, when the hydraulic pressure of the wheel brake side hydraulic pressure paths 4A and 4C is applied to the parking control hydraulic pressure chamber 106 in a state where the first and second pumps 10A and 10B are operated, the parking is performed. Since the piston 103 moves forward and the lock mechanism 105 mechanically locks the advance position of the parking piston 103, the parking brake state can be obtained automatically. When the parking brake state is released, the wheel brake side hydraulic pressure is The parking brake state can be automatically obtained with a simple structure as long as the hydraulic pressure of the paths 4A and 4C is applied to the lock mechanism 105.

  Moreover, the control unit C for controlling the operation of the electric motor 11, the pressure regulating valves 17A and 17B, the suction valves 18A and 18B, the control valve means VA and VC, and the normally closed electromagnetic valves 66A and 66B has a second function during the automatic parking brake. All the wheel brakes 2A to 2D are braked so that the hydraulic pressure of the hydraulic pressure source hydraulic pressure paths 20A and 20B, which is the output hydraulic pressure of the hydraulic pressure sources 5A and 5B, is applied to each of the wheel brake side hydraulic pressure paths 4A to 4D. The first step of actuating and holding the parking piston 103 of the left and right front wheel brakes 2A, 2c in the retracted position, and the second hydraulic pressure sources 5A, 5B to the all-wheel brake side hydraulic pressure paths 4A-4D. The wheel brake side hydraulic pressure paths 4A, 4 connected to the left and right front wheel brakes 2A, 2C in a state where the acting hydraulic pressure is higher than that in the first step. A second step of causing the parking mechanism 103 to act on the locking mechanism 105 as a parking release control fluid pressure and a parking control fluid pressure on the parking piston 103 as a parking control fluid pressure In this state, the operation of the second hydraulic pressure sources 5A and 5B is stopped, and the third step of releasing the parking release control hydraulic pressure is sequentially executed.

  According to such processing at the time of automatic parking brake, it is necessary to continue the operation of the second hydraulic pressure sources 5A and 5B until the second step, and in the third step, for the hidari and the right front wheel. Since the locking mechanism 105 of the wheel brakes 2A and 2C mechanically locks the advance position of the parking piston 103 and maintains the parking brake state, the parking control fluid pressure and the parking release control fluid pressure are not required. The operation of the electromagnetic valves 66A and 66B for controlling the operation is also unnecessary. Therefore, the automatic parking brake state can be obtained with a simple structure with reduced energy consumption.

  Moreover, when only the left and right front wheel brakes 2A and 2C are operating the parking brake, rather than the hydraulic pressure acting on each wheel brake 2A to 2D when all the wheel brakes 2A to 2D are operating. Furthermore, since the hydraulic pressure acting on the parking piston 103 of the left and right front wheel brakes 2A, 2C is high, the relative change in the braking force of the entire vehicle can be kept small even if the number of wheel brakes operating is reduced. Can do.

  FIG. 5 shows a second embodiment of the present invention. Parking control means 67A that can obtain the hydraulic pressure of the wheel brake side hydraulic pressure passage 4A as the parking control hydraulic pressure and the parking release control hydraulic pressure. 'Is between the normally closed electromagnetic valve 66A interposed between the wheel brake side hydraulic pressure passage 4A and the parking control hydraulic pressure chamber 106, and between the wheel brake side hydraulic pressure passage 4A and the parking release control hydraulic pressure chamber 109. It may be composed of a normally closed electromagnetic valve 69 interposed between the two.

  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. It is.

1 is a hydraulic circuit diagram of a vehicle brake device according to a first embodiment. It is a longitudinal cross-sectional view of the disc brake at the time of a non-parking brake. It is a principal part enlarged view of FIG. It is a block diagram which shows the structure of the control system relevant to the automatic parking brake of the wheel brake for left front wheels. It is sectional drawing corresponding to FIG. 3 of 2nd Example.

Explanation of symbols

2A, 2B, 2C, 2D ... wheel brakes 4A, 4B, 4C, 4D ... wheel brake side hydraulic pressure paths 5A, 5B ... second hydraulic pressure sources 67A, 67A ', 67B ... parking Control means 102 ... casing 103 ... parking piston 105 ... lock mechanism C ... control unit M ... master cylinders VA, VB, VC, VD as the first hydraulic pressure source ... control Valve means

Claims (1)

  A first hydraulic pressure source (M) that outputs hydraulic pressure in response to a brake operation, and a second hydraulic pressure source (5A, 5A, that can output hydraulic pressure for executing automatic brake control in a non-brake operating state 5B), wheel brake side hydraulic pressure paths (4A, 4B, 4C, 4D) individually connected to the plurality of wheel brakes (2A, 2B, 2C, 2D), and first and second hydraulic pressure sources (M, Control valve means (VA, VB, VC, VD) capable of controlling the output hydraulic pressure of 5A, 5B) to act on the wheel brake side hydraulic pressure passages (4A-4D), and automatically operating in a non-brake operation state In the vehicle brake device capable of obtaining a parking brake, a parking control hydraulic pressure is applied to a casing (102) included in a wheel brake (2A, 2C) with a parking brake mechanism among the plurality of wheel brakes (2A to 2D). On the action of A parking piston (103) that is slidably fitted so as to be able to obtain an automatic parking brake state by a forward movement, and the parking piston (103) to mechanically lock the parking piston (103) in the forward position. 103) is automatically locked in accordance with the forward movement operation and also in the casing (102) behind the parking piston (103) so as to be unlocked in response to the operation of the parking release control hydraulic pressure. And a hydraulic pressure of the wheel brake side hydraulic path (4A, 4C) to a wheel brake side hydraulic path (4A, 4C) connected to a wheel brake (2A, 2C) with a parking brake mechanism. Can be obtained as the parking control fluid pressure and the parking release control fluid pressure. Parking control means (67A, 67B; 67A '), the second hydraulic pressure source (5A, 5B), the control valve means (VA, VC), and the parking control configured so that the output hydraulic pressure is variable A control unit (C) for controlling the operation of the means (67A, 67B; 67A ′), and during the automatic parking brake, the control unit (C) outputs the hydraulic pressure of the second hydraulic pressure source (5A, 5B). To act on all the wheel brake side hydraulic pressure passages (4A to 4D), to brake all wheel brakes (2A to 2C) and to the parking pistons (2A, 2C) of the parking brake mechanism (2A, 2C). 103) at the reverse position, and the hydraulic pressure acting on the all-wheel brake side hydraulic paths (4A to 4D) from the second hydraulic pressure source (5A, 5B). The pressure of the wheel brake side hydraulic pressure passages (4A, 4C) connected to the wheel brakes (2A, 2C) with the parking brake mechanism in a state where the pressure is increased from that in the first step is set to the parking release control liquid. A second step in which the pressure is applied to the locking mechanism (105) as a pressure and the parking piston (103) as the control fluid pressure for parking; and the parking control fluid pressure is applied to the parking piston (103). A vehicle brake device characterized by sequentially executing the third step of stopping the operation of the second hydraulic pressure source (5A, 5A) and releasing the parking release control hydraulic pressure in the state.

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