JP4084791B2 - Brake device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an automatic parking brake state by reducing energy consumption. <P>SOLUTION: A lock mechanism 105 is provided in a casing 102 at a rear side of a parking piston 103, for automatically executing a locking operation according to a forward movement operation of the parking piston 103 to mechanically lock the parking piston 103, enabling the parking brake state by forward movement operation according to an effect of control fluid pressure for parking, at its forward movement position. In the parking brake state, a wheel brake is made to conduct braking operation by output fluid pressure of a second fluid pressure source 5A while keeping the parking piston 103 at its retreat position, After the parking brake state is maintained for a predetermined period of time, control fluid pressure for parking cancellation is applied to the lock mechanism 105 and the control fluid pressure for parking is applied to the parking piston 103 and then operation of the second fluid pressure source 5A is stopped and the control fluid pressure for parking cancellation is released. <P>COPYRIGHT: (C)2006,JPO&amp;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 constant hydraulic pressure for executing automatic brake control in a non-brake operating state, And a control valve means for controlling the output hydraulic pressure of the first and second hydraulic pressure sources to act on the wheel brake side hydraulic pressure passage connected to the wheel brake, and when the non-brake operation is performed, The present invention relates to a vehicular brake device capable of obtaining an automatic parking brake state by automatically operating the wheel brake using output hydraulic pressure.

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 the above-mentioned Patent Document 1, an automatic parking brake is used in which an automatic parking brake state of a wheel brake is obtained using output hydraulic pressure under hydraulic pressure that outputs hydraulic pressure during non-braking operation. As long as the 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 continue, and if the duration of the automatic parking brake state becomes longer, a problem occurs in terms of energy consumption .

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a vehicle brake device that can reduce an energy consumption and obtain an automatic parking brake state.

In order to achieve the above object, the present invention outputs a first hydraulic pressure source that outputs hydraulic pressure in response to a brake operation, and a constant hydraulic pressure for executing automatic brake control in a non-brake operating state. A second hydraulic pressure source to be obtained, and 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 pressure passage connected to the wheel brake, and performing non-brake operation In the vehicular brake device capable of obtaining an automatic parking brake state by automatically operating the wheel brake by using the output hydraulic pressure of the second hydraulic pressure source sometimes, the action of the parking control hydraulic pressure a parking piston the wheel brake is a casing slidably fitted into engagement with the can to obtain an automatic parking brake state of the wheel brake by the forward operation according to, The control fluid pressure for releasing the king can be applied to the rear, and the lock piston slidably fitted to the casing behind the parking piston and the parking piston urged toward the forward operation side. A spring that exerts a spring force that moves the lock piston forward by the spring force of the spring according to the forward movement of the parking piston, and automatically locks the parking piston at the forward position, The lock piston is retracted in accordance with the action of the control hydraulic pressure, and the lock is provided in the casing so as to release the lock, and the hydraulic pressure in the wheel brake side hydraulic pressure path is set to the parking control hydraulic pressure and the parking hydraulic pressure. It can be obtained as the control hydraulic pressure for parking release and connected to the wheel brake side hydraulic pressure path. A parking control means, and a control unit for controlling the operation of the second hydraulic pressure source, the control valve means and the perking control means to obtain an automatic parking brake state of the wheel brake, the control unit comprising: A first step of braking the wheel brake by applying the output hydraulic pressure of the second hydraulic pressure source to the wheel brake side hydraulic pressure path and holding the parking piston in the reverse position during automatic parking brake; After the parking brake state of the wheel brake by the process of the first step continues for a predetermined time, the hydraulic pressure of the wheel brake side hydraulic pressure path is applied to the lock mechanism as the parking release control hydraulic pressure and the parking brake A second step is applied to the parking piston as a control hydraulic pressure. And a third step of stopping the operation of the second hydraulic pressure source and releasing the parking release control hydraulic pressure.

  According to such a configuration of the invention, the wheel brake is braked using the output hydraulic pressure of the second hydraulic pressure source in the first step, and the hydraulic pressure in the wheel brake side hydraulic pressure path is adjusted in the second step. The parking piston moves forward by acting as a control fluid pressure for parking, and in the third step, the lock mechanism mechanically locks the advance position of the parking piston. Therefore, it is necessary to continue the operation of the second fluid pressure source. Until the second step, the lock mechanism mechanically locks the advance position of the parking piston and maintains the parking brake state in the third step. Therefore, the parking control fluid pressure and the parking release control fluid are maintained. No pressure is required, and the operation of a solenoid valve for controlling the hydraulic pressure is also unnecessary. Therefore, the automatic parking brake state can be automatically obtained with a simple structure with reduced energy consumption.

  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 respective inlet valves 6A to 6D.

  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 and 10B and the pressure regulating valves 17A and 17B constitute second hydraulic pressure sources 5A and 5B that output a constant hydraulic pressure to the hydraulic pressure source hydraulic pressure paths 20A and 20B during non-braking operation. By controlling the constant hydraulic pressures of the hydraulic pressure source hydraulic pressure paths 20A and 20B by 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 stabilization control and traction control during traveling can be executed.

  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 adjustment mechanism 82 is provided in the first pinching arm 75a of the brake caliper 75. The adjustment mechanism 82 is connected to the brake piston 78 so as not to rotate relative to the brake piston 78, 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. The relay piston 85 is fluid-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 screw grooves 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 respective 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 in 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.

  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 output of the second hydraulic pressure source 5A. The left front wheel brake 2A is braked so that the hydraulic pressure acts on the wheel brake side hydraulic pressure passage 4A, and the parking piston 103 is held in the retracted position. That is, the control unit C excites and opens the suction valve 18A with the normally closed electromagnetic valve 66A of the parking control means 67A closed, drives the first pump 10A by the electric motor 11, and operates the pressure regulating valve 17A. Is controlled so that the inlet valve 6A of the control valve means VA is demagnetized and held open while the hydraulic pressure of the hydraulic pressure source hydraulic path 20A is kept constant. Is applied to the wheel side brake hydraulic pressure passage 4A. As a result, the constant hydraulic pressure output from the second hydraulic pressure source 5A is applied to the brake hydraulic pressure chamber 80 and to the parking release control hydraulic pressure chamber 109, and the forward movement of the lock piston 104 is suppressed. Then, the brake piston 78 is advanced.

  In the next second step, the control unit C controls the parking pressure of the wheel brake side hydraulic path 4A to cancel the parking after the parking brake state of the left front wheel brake 2A in the first step has continued for a predetermined time. A hydraulic pressure is applied to the lock mechanism 105 and a parking control hydraulic pressure is applied to the parking piston 103. That is, the control unit C opens the normally closed solenoid valve 66A of the parking control means 67A to apply the hydraulic pressure of the wheel brake side hydraulic pressure path 4A to the parking control hydraulic pressure chamber 106, thereby causing the parking piston 103 Move forward.

  In the subsequent third step, the control unit C stops the operation of the second hydraulic pressure source 5 and releases the parking release control hydraulic pressure. That is, the control unit C stops driving the first pump 10A by the electric motor 11, demagnetizes and opens the pressure regulating valve 17A, demagnetizes and closes the suction valve 18A, and demagnetizes and closes the normally closed electromagnetic valve 66A. Return to the valve state. Then, the hydraulic pressure in the parking release control hydraulic pressure chamber 109 is released, the lock piston 104 is moved forward by the spring force of the spring 114, and the lock mechanism 105 is moved to the spheres 52, 52 according to the advance of the parking piston 103 and the lock piston 104. 52 is engaged with the engaging step 101f.

  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. 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 the parking brake state is obtained during normal braking operation, if the detected value of the pressure sensor 15A is sufficiently high, the first pump 10A is not driven by the electric motor 11, and the pressure regulating valve 17A is demagnetized and fully opened. The normally closed solenoid valve 66A may be excited and opened while the suction valve 18A is demagnetized and closed. When the detected value of the pressure sensor 15A is low, the same processing as in the automatic parking brake described above is executed. That's fine.

  When releasing the parking brake state, the suction valve 18A is excited and opened, the first pump 10A is driven by the electric motor 11, and the operation of the pressure regulating valve 17A is controlled to control the hydraulic pressure in the hydraulic pressure source hydraulic path 20A. With the pressure held constant, the hydraulic pressure of the hydraulic pressure source hydraulic pressure path 20A is applied to the wheel side brake hydraulic pressure path 4A, and the normally closed electromagnetic valve 66A 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.

  The right front wheel brake 2C is configured in the same manner as the left front wheel brake 2A described above. When the right front wheel brake 2C obtains the automatic parking brake state, it is the same as the left front wheel brake 2A. The electric motor 11, the pressure regulating valve 17B, the suction valve 18B, the control valve means VC and a part of the parking control means 67B constituting the second hydraulic pressure source 5B together with the second pump 10B driven by the electric motor 11 are provided. What is necessary is just to control the action | operation of the normally closed solenoid valve 66B to comprise by the control unit C. FIG.

  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 is a left and right front wheel brake 2A. , 2C, the left and right front wheel wheel brakes 2A, 2C are braked so that the output hydraulic pressure of the second hydraulic pressure source 5A, 5B is applied to the wheel brake side hydraulic pressure paths 4A, 4C. A first step of squeezing and holding the parking piston 103 in the retracted position, and a wheel brake side hydraulic path after the parking brake state of the left and right front wheel brakes 2A, 2C by the processing of the first step continues for a predetermined time The hydraulic pressures 4A and 4C are applied to the lock mechanism 105 as the parking release control hydraulic pressure and The second step of causing the parking piston 103 to act as the control hydraulic pressure for the parking and the third step of stopping the operation of the second hydraulic pressure sources 5A and 5B and releasing the control hydraulic pressure for releasing the parking are sequentially executed. To do.

  According to such a process, 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, the lock mechanism 105 is moved forward of the parking piston 103. Since the parking brake state is maintained by mechanically locking the control valve, neither the parking control fluid pressure nor the parking release control fluid pressure is required, and the normally closed solenoid valves 66A and 66B for controlling the fluid pressure are also operated. It becomes unnecessary. Therefore, the automatic parking brake state can be automatically obtained with a simple structure with reduced energy consumption.

  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. FIG. 3 is an enlarged view of a main part of FIG. 2. 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, 2C ... wheel brakes 4A, 4C ... 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, VC as first hydraulic pressure sources ... 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) that can output a constant hydraulic pressure for executing automatic brake control in a non-brake operating state , 5B) and the hydraulic pressure passages (4A, 4C) connected to the wheel brakes (2A, 2C) by controlling the output hydraulic pressures of the first and second hydraulic pressure sources (M, 5A, 5B). Control valve means (VA, VC) that can act, and automatically brake the wheel brakes (2A, 2C) using the output hydraulic pressure of the second hydraulic pressure source (5A, 5B) during non-braking operation In a vehicle brake device capable of obtaining an automatic parking brake state by actuating,
It is possible to obtain the automatic parking brake state of the wheel brakes (2A, 2C) by a forward operation according to the action of the control fluid pressure for parking, and to slide on the casing (102) included in the wheel brakes (2A, 2C). A parking piston (103) fitted to
A lock piston (104) that is slidably fitted to the casing (102) behind the parking piston (103) so that the parking release control hydraulic pressure can be applied rearward, and the parking The lock piston (103) has a spring (114) that exerts a spring force that urges the piston (103) to the forward operation side, and the lock piston is moved by the spring force of the spring (114) in accordance with the forward operation of the parking piston (103). (104) is moved forward, and the parking piston (103) is automatically locked at the forward movement position, while the lock piston (104) is moved backward according to the action of the parking release control hydraulic pressure to release the lock. A locking mechanism (105) provided in the casing (102),
It is possible to obtain the hydraulic pressure of the wheel brake side hydraulic pressure passage (4A, 4C) as the parking control hydraulic pressure and the parking release control hydraulic pressure and is connected to the wheel brake side hydraulic pressure passage (4A, 4C). Parking control means (67A, 67B; 67A '),
The second hydraulic pressure source (5A, 5B), the control valve means (VA, VC) and the perking control means (67A, 67B; 67A ′) to obtain an automatic parking brake state of the wheel brakes (2A, 2C) A control unit (C) for controlling the operation of
During the automatic parking brake, the control unit (C) applies the output hydraulic pressure of the second hydraulic pressure source (5A, 5B) to the wheel brake side hydraulic pressure passage (4A, 4B) so as to make the wheel brake. A first step of braking (2A, 2C) and holding the parking piston (103) in a retracted position;
After the parking brake state of the wheel brakes (2A, 2C) by the process of the first step continues for a predetermined time, the hydraulic pressure of the wheel brake side hydraulic pressure paths (4A, 4B) is used as the parking release control hydraulic pressure. A second step of acting on the locking mechanism (105) and acting on the parking piston (103) as the control fluid pressure for parking;
A vehicle brake device characterized by sequentially performing a third step of stopping the operation of the second hydraulic pressure source (5A, 5A) and releasing the parking release control hydraulic pressure.

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