JP2008254464A - Vehicular brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid reduction of boost response while enhancing a layout property on a vehicle body without using a high pressure accumulator in which a thick housing is used, in a vehicular brake device in which the output liquid pressure of a liquid pressure generation source is regulated by a pressure-regulation valve means operated according to brake operation input and is applied to a double force hydraulic chamber to which the back surface of a mater piston is faced. <P>SOLUTION: The liquid pressure generation source is constituted only by a pump 6, and an accumulator 59 is connected to the pump 6 through a valve 78 for suppressing the flow of a brake liquid to the pump 6 side at least at non-operation of the pump 6. Between the double force hydraulic chamber 9 and the accumulator 59, an inlet valve 66 is interposed, which is opened according to that the liquid pressure at the accumulator 59 side becomes higher than the liquid pressure at the double force hydraulic chamber 9 side so as to exceed the set differential pressure and is opened by pressing force mechanically acted from the brake operation member 5 at an initial stage of brake operation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes a hydraulic cylinder including at least a master cylinder in which a master piston facing the back of a boost hydraulic chamber is slidably accommodated in a casing, a reservoir, and a pump for discharging brake fluid pumped from the reservoir. And a pressure regulating valve means for regulating the output hydraulic pressure of the hydraulic pressure generating source according to a brake operation input from a brake operating member and acting on the boosted hydraulic pressure chamber. The present invention relates to a vehicle brake device connected to the vehicle.

Such a vehicle brake device is already known from, for example, Patent Document 1 and the like.
JP 2002-264895 A

  However, in the vehicle brake device disclosed in Patent Document 1, the hydraulic pressure generation source includes a pump and a high-pressure accumulator connected to the pump. Since the high-pressure accumulator can withstand high pressure, Since the thickness is increased and the weight is increased, the hydraulic pressure generation source becomes heavier and the layout is not good when mounted on the vehicle body. Therefore, it is conceivable to omit the high-pressure accumulator and configure the hydraulic pressure generation source with only the pump.

  The present invention has been made in view of such circumstances, and is capable of avoiding a decrease in boosting response while improving layout to a vehicle body without using a high-pressure accumulator in which a thick-walled housing is used. An object of the present invention is to provide a vehicle brake device.

  In order to achieve the above object, a first aspect of the present invention is directed to a master cylinder in which a master piston having a back face facing a boosted hydraulic pressure chamber is slidably accommodated in a casing, a reservoir, and a pump from the reservoir A hydraulic pressure generating source including at least a pump that discharges the brake fluid, and adjusting the output hydraulic pressure of the hydraulic pressure generating source according to the brake operation input from the brake operating member and acting on the boosted hydraulic pressure chamber. A brake device for a vehicle in which the master cylinder is connected to a wheel brake, and the hydraulic pressure generation source is constituted only by the pump, and at least when the pump is not operated, the brake fluid is supplied to the pump side. An accumulator is connected to the pump via a valve that prevents flow, and the hydraulic pressure on the accumulator side is doubled between the boost hydraulic chamber and the accumulator. An inlet valve that opens as the hydraulic pressure on the hydraulic pressure chamber side exceeds the set differential pressure and opens with a pressing force that acts mechanically from the brake operating member at the initial stage of brake operation is provided. It is characterized by being.

  According to a second aspect of the invention, in addition to the configuration of the first aspect of the invention, the pump is connected to the accumulator through an orifice.

  According to a third aspect of the present invention, in addition to the configuration of the first or second aspect of the present invention, an on-off valve that opens in a brake operation state except an initial brake operation is interposed between the pump and the accumulator. It is characterized by.

  According to a fourth aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the pressure regulating valve means allows only the flow of brake fluid from the pump side, and the pump and the A release composed of a one-way valve provided between the boosting hydraulic pressure chamber and a linear solenoid valve interposed between the boosting hydraulic pressure chamber and the reservoir, and opened according to an arbitrary operation of the vehicle driver. A valve is provided between the boost hydraulic chamber and the reservoir in parallel with the linear solenoid valve.

  Further, the invention according to claim 5 is characterized in that, in addition to the configuration of the invention according to claim 4, the linear solenoid valve is a normally closed type and the release valve is a normally closed solenoid valve.

  According to the first aspect of the present invention, the hydraulic pressure generating source is composed of only a pump, and a high-pressure accumulator using a thick-walled housing need not be used. it can. In addition, during non-brake operation after braking, the inlet valve is closed with the hydraulic pressure below the set differential pressure accumulated in the accumulator due to a decrease in the hydraulic pressure in the boost hydraulic chamber. By opening the valve with a pressing force that mechanically acts from the brake operating member, the hydraulic pressure equal to or lower than the set differential pressure from the accumulator acts on the boost hydraulic chamber in response to the opening of the inlet valve. become. Therefore, by setting the accumulator capacity and the differential pressure, which is the accumulator holding pressure, small enough to initially operate the master cylinder, the capacity and weight of the accumulator can be increased to enhance the layout on the vehicle body. It is possible to avoid a decrease in the boosting response while reducing.

  According to the second aspect of the present invention, pulsation can be prevented from occurring in the hydraulic pressure acting on the accumulator from the pump.

  According to the third aspect of the present invention, the pump discharge pressure is guided to the accumulator during normal brake operation excluding the initial stage of the brake operation, and the inlet valve is set according to the decrease in the hydraulic pressure in the boost hydraulic chamber after the brake operation is completed. By closing the valve after opening, the accumulator can accumulate the hydraulic pressure.

  According to the fourth aspect of the present invention, the pressure regulating valve means can be simply constituted by a one-way valve and a linear solenoid valve, and the hydraulic pressure in the boost hydraulic pressure chamber is locked when the pressure regulating valve means is out of order. This can be avoided with a simple configuration.

  According to the fifth aspect of the present invention, during normal brake operation, the normally closed linear solenoid valve may be excited and opened to reduce the hydraulic pressure in the boost hydraulic chamber, and the release valve Since it is only necessary to maintain a demagnetization and valve closing state, power consumption can be suppressed.

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

  1 to 3 show an embodiment of the present invention, FIG. 1 is a brake hydraulic system diagram showing the overall configuration of a vehicle brake device, and FIG. 2 is a hydraulic circuit diagram showing the configuration of a hydraulic modulator. FIG. 3 is an enlarged view of a main part of FIG.

  First, in FIG. 1, a brake device for a four-wheel vehicle includes a master cylinder M that is a tandem type and a fluid of a pump 6 that is a fluid pressure generation source in accordance with a brake operation force input from a brake pedal 5 as a brake operation member. A pressure regulating valve means 7 that regulates the pressure to act on the master cylinder M and a stroke simulator 8 that simulates the operation stroke of the brake pedal 5 are provided.

  The master cylinder M is disposed in front of the rear master piston 10 with the rear face facing the boost hydraulic chamber 9 and spring-biased to the rear side, and spring-biased to the rear side. The rear master piston 10 and the front master piston 11 are slidably fitted to the first casing 12.

  The first casing 12 is provided with a first cylinder hole 13 whose front end is closed by an end wall 12a. The front master piston 11 is formed in a bottomed cylindrical shape with the front end opened, and a front output hydraulic pressure chamber 14 is formed between the front master piston 11 and the end wall 12a so as to be slidable in the first cylinder hole 13. Mated. The rear master piston 10 is slidably fitted into the first cylinder hole 13 by forming a rear output hydraulic pressure chamber 15 between the rear master piston 10 and the front master piston 11. Moreover, the rear master piston 10 includes a first recess 16 that opens the rear output hydraulic chamber 13 side and a second recess 17 that opens the boost hydraulic chamber 9 side, with a partition wall 10a interposed therebetween. It is provided coaxially.

  In the front output hydraulic pressure chamber 14, a front return spring 18, which is contracted between the closed end of the front master piston 11 having a bottomed cylindrical shape and the end wall 12 a, moves the front master piston 11 to the rear. The rear output hydraulic pressure chamber 13 is accommodated so as to exert a spring force biased to the side, and a rear return spring 19 that is contracted between the partition wall 10a of the rear master piston 10 and the front master piston 11 is provided. The rear master piston 10 is accommodated so as to be biased rearward.

  On the inner periphery of the first cylinder hole 13, there are a rear lip seal 22 slidably contacting the outer periphery of the rear master piston 10, and an annular seal member 23 slidably contacting the outer periphery of the rear master piston 10 behind the rear lip seal 22. The first casing 12 is provided with a rear release port 24 that is mounted and communicates between the first casing 12 and the rear master piston 10 between the rear lip seal 22 and the annular seal member 23. The rear release port 24 is connected to the second liquid reservoir chamber 26 of the reservoir R, and the rear lip seal 22 has a hydraulic pressure in the rear output hydraulic chamber 15 between the rear lip seal 22 and the annular seal member 23. When the hydraulic pressure in the gap generated between the rear master piston 10 and the first casing 12, that is, the hydraulic pressure in the second liquid reservoir chamber 26, decreases from the second liquid reservoir chamber 26 to the rear output hydraulic chamber 15 side. Allow fluid flow. Further, the rear master piston 10 is provided with a relief hole 28 that allows the rear release port 24 to communicate with the rear output hydraulic pressure chamber 15 at the retreat limit position (position shown in FIG. 1).

  On the inner periphery of the first cylinder hole 13, a front lip seal 29 slidably contacting the outer periphery of the front master piston 11 and an annular seal slidably contacting the outer periphery of the front master piston 11 behind the front lip seal 29. A member 30 is mounted at an interval in the axial direction, and a gap formed between the inner periphery of the first cylinder hole 13 and the outer periphery of the front master piston 11 between the front lip seal 29 and the annular seal member 30. A front release port 31 that communicates with the first casing 12 is provided, and the front release port 31 is connected to the first liquid reservoir chamber 25 of the reservoir R. Thus, the front lip seal 29 is a gap in which the hydraulic pressure in the front output hydraulic chamber 14 is generated between the front master piston 11 and the first casing 12 between the front lip seal 29 and the annular seal member 30. When the hydraulic pressure is lower than the hydraulic pressure of the first fluid reservoir chamber 25, the brake fluid is allowed to flow from the first fluid reservoir chamber 25 to the front output hydraulic chamber 14 side. Further, the front master piston 11 is provided with a relief hole 32 that allows the front release port 31 to communicate with the front output hydraulic pressure chamber 14 at the retreat limit.

  The first casing 12 has a rear output port 33 that outputs the hydraulic pressure of the rear output hydraulic pressure chamber 15 that becomes high pressure according to the forward operation of the rear master piston 10, and the forward operation of the front master piston 11. A front output port 34 that outputs the hydraulic pressure of the front output hydraulic pressure chamber 14 that is high pressure is provided. In addition, the rear output port 33 is connected to the right front wheel and left rear wheel brakes BA and BB via a hydraulic pressure modulator 35, and the front output port 34 is connected to the left front wheel and right rear wheel via the hydraulic pressure modulator 35. Connected to wheel brakes BC and BD. A hydraulic pressure sensor 36 is connected to the front output port 34.

  In FIG. 2, the hydraulic pressure modulator 35 is provided between a rear output port 33 and a right front wheel wheel brake BA, a normally open solenoid valve 37A, and a rear output port 33 and a left rear wheel wheel brake BB. A normally open solenoid valve 37B provided, and one-way valves 38A and 38B connected in parallel to the normally open solenoid valves 37A and 37B, respectively, allowing the brake fluid to flow to the rear output port 33 side. A normally closed solenoid valve 39A interposed between the right front wheel brake BA and the first reservoir 40A, and a normally closed solenoid valve 39B interposed between the left rear wheel brake BB and the first reservoir 40A. A normally open solenoid valve 37C interposed between the front output port 34 and the left front wheel wheel brake BC, and a normally open type valve interposed between the front output port 34 and the right rear wheel wheel brake BD. solenoid valve 7D, one-way valves 38C and 38D connected in parallel to the normally open solenoid valves 37C and 37D, respectively, allowing the brake fluid to flow to the front output port 34 side, and the wheel brake BC for the left front wheel The normally closed solenoid valve 39C interposed between the second reservoir 40B, the right rear wheel brake BD and the second reservoir 40B, the normally closed solenoid valve 39D, and the first reservoir 40A. A first pump 41A that pumps up the hydraulic pressure and returns it to the rear output port 33 side, a second pump 41B that pumps up the hydraulic pressure of the second reservoir 40B and returns it to the front output port 34 side, and first and second pumps 41A, Between the electric motor 42 that drives 41B in common, the first orifice 43A interposed between the first pump 41A and the rear output port 33, and between the second pump 41B and the front output port 34 And a second orifice 43B to be set.

  According to such a hydraulic pressure modulator 35, the brake hydraulic pressure output from the rear and front output ports 33 and 34 can be freely adjusted, and antilock brake control at the time of brake operation can be performed.

  In FIG. 1 again, the stroke simulator 8 has a second cylinder hole 47 that is coaxial with the first cylinder hole 13 and has a diameter larger than that of the first cylinder hole 13, and is liquid-tight at the rear portion of the first casing 12. The boosted hydraulic pressure chamber 9 that faces the rear portion of the rear master piston 10 in the master cylinder M is formed between the second casing 48 that is coaxially coupled to the rear end of the first casing 12. A backup piston 49 slidably fitted in the second cylinder hole 47, and an outward flange 50a that abuts from the front on an inward flange 48a provided at the rear end of the second casing 48 in the axially intermediate portion. A cylindrical sleeve 50 having a front half fitted in the backup piston 49, a simulator piston 51 slidably fitted in the sleeve 50, and a simulator piston 51, an input piston 52 fitted to be slidable relative to 51, an elastic body 53 interposed between the input piston 52 and the simulator piston 51, and a first casing 12 and the backup piston 49. The spring 54 is provided.

  The backup piston 49 has a first sliding hole 55 opened rearward so as to fit the front half of the sleeve 50, and the inward flange 48 a at the rear end of the second casing 48 has the above-mentioned By abutting through the outward flange portion 50a of the sleeve 50, the retreat limit position is regulated so as to be slidably fitted into the second cylinder hole 47. A contact protrusion 49a is coaxially provided at the front end of the backup piston 49, and the contact protrusion 49a is formed in the second recess 17 provided in the rear master piston 10 of the master cylinder M with a second recess. 17 is inserted so that the tip can be brought into contact with the closed end, that is, the partition wall 10a.

  A pair of annular seal members 56 and 57 slidably in contact with the inner periphery of the second cylinder hole 47 are mounted on the outer periphery of the backup piston 49 with an interval in the axial direction between the annular seal members 56 and 57. Thus, a communication hole 58 that opens to the inner surface of the second cylinder hole 47 is provided in the second casing 48, and this communication hole 58 communicates with the accumulator chamber 61 of the accumulator 59.

  The accumulator 59 is a bottomed cylindrical accumulator piston that is slidably fitted into the housing 60 by forming an accumulator chamber 61 between the cylindrical housing 60 closed at both ends and one end of the housing 60. 62, and an accumulator spring 63 that is contracted between the other end of the housing 60 and the accumulator piston 62 by exerting a spring force that urges the accumulator piston 62 toward the volume reducing side of the accumulator chamber 61, It is relatively small.

  Thus, an inlet valve 66 is interposed between the boosted hydraulic pressure chamber 9 and the accumulator 59, and this inlet valve 66 is built in the front portion of the backup piston 49.

  In FIG. 3, the backup piston 49 has a second sliding hole 67 into which a fitting protrusion 51a provided at the front end of the simulator piston 51 is fitted in a fluid-tight manner so as to be relatively slidable. The annular stepped portion 68 is provided with a smaller diameter than the front end of the first sliding hole 55 so as to be coaxial with the front end of the fitting projection 51a so as to contact the front end of the fitting projection 51a. A valve hole 69 formed between the front end of the moving hole 67, a valve chamber 70 communicating with the front end of the valve hole 69, and the valve chamber 70 sandwiched between the valve hole 69 and coaxial with the valve hole 69. An extended communication hole 71 is provided from the front part of the backup piston 49 to the contact protrusion 49a, and the front end of the communication hole 71 is always in communication with the boost hydraulic chamber 9 at the front end of the contact protrusion 49a. Open.

  The inlet valve 66 includes a valve body 73 accommodated in the valve chamber 70 so that the valve hole 69 can be closed by being seated on a valve seat 72 formed at the peripheral edge of the front end of the valve hole 69, and the valve body 73. A valve spring 74 that is contracted between the contact protrusion 49a and the valve body 73 by exerting a spring force to be urged so as to be seated on the valve seat 72, and a valve spring 73 that is connected to the valve body 73 to the valve hole 69. The valve-opening rod 75 is coaxially inserted, and the rear end of the valve-opening rod 75 is brought into contact with the front end of the fitting projection 51 a of the simulator piston 51.

  Thus, a liquid chamber 76 is formed in the backup piston 49 between the front end of the fitting projection 51 a and the annular stepped portion 68, and a communication passage 77 for communicating the liquid chamber 76 with the communication hole 58 is formed. A backup piston 49 is provided.

  The holding pressure of the accumulator 59 acts on the liquid chamber 76, and the liquid pressure due to the liquid pressure of the liquid chamber 76 acts in the valve opening direction on the valve body 73 in the valve closing position. On the other hand, the valve body 73 at the valve closing position is closed by the hydraulic pressure due to the hydraulic pressure of the valve chamber 70 communicating with the boost hydraulic chamber 9 through the communication hole 71 and the spring force of the valve spring 74. In the inlet valve 66, the fluid pressure in the valve opening direction by the fluid pressure obtained by subtracting the fluid pressure in the valve chamber 70, that is, the boost fluid pressure chamber 9, from the fluid pressure in the fluid chamber 76, that is, the accumulator 59, is The valve opens when the spring force of the valve spring 74 is overcome.

  In the initial stage of the brake operation by the brake pedal 5, a force in the direction of moving forward with respect to the backup piston 49 acts on the simulator piston 51 from the input piston 52 through the elastic body 53. The valve opening rod 75 is pressed by the forward operation of the mating protrusion 51a with respect to the backup piston 49, and the inlet valve 66 is also opened.

  That is, the inlet valve 66 opens in response to the hydraulic pressure on the accumulator 59 side becoming higher than the hydraulic pressure on the boost hydraulic pressure chamber 9 side exceeding the set differential pressure corresponding to the spring load of the valve spring 74. At the same time, the valve is opened by a pressing force that is mechanically applied from the brake pedal 5 in the initial stage of the brake operation.

  In FIG. 1 again, a pump 6 as a hydraulic pressure generation source pumps up brake fluid from the third liquid reservoir chamber 27 of the reservoir R, and the discharge port of this pump 6 is at least when the pump 6 is not in operation. A first one-way valve 78 that is a valve that blocks the flow of brake fluid to the side, a third orifice 79, and a normally-open electromagnetic valve 80 that is an on-off valve that opens in a brake operation state other than the initial brake operation To the accumulator chamber 61 of the accumulator 59.

  The second casing 48 is provided with a supply port 81 that communicates with the boosted hydraulic pressure chamber 9, and a hydraulic pressure path 82 is connected to the supply port 81. Thus, the pressure regulating valve means 7 includes a second one-way valve 83 provided between the pump 6 and the hydraulic pressure passage 82 so as to allow only the flow of brake fluid from the pump 6, and the hydraulic pressure passage. 82 and a linear solenoid valve 84 provided between the third liquid reservoir chamber 27 of the reservoir R, and a hydraulic pressure sensor for detecting the hydraulic pressure in the boosted hydraulic pressure chamber 9 is provided in the hydraulic pressure path 82. 109 is connected.

  In addition, a release valve 103 that opens in response to an arbitrary operation of the vehicle driver is a linear solenoid between a hydraulic pressure path 82 communicating with the boosted hydraulic pressure chamber 9 and the third fluid reservoir chamber 27 of the reservoir R. The release valve 103 is a normally closed electromagnetic valve.

  The simulator piston 51 is provided with a bottomed third sliding hole 85 opened coaxially on the rear side, and an annular seal member 86 slidably contacting the inner periphery of the third sliding hole 85 is mounted on the outer periphery. The input piston 52 is slidably fitted into the third sliding hole 85, and the front end portion of the input rod 87 connected to the brake pedal 5 is connected to the input piston 52 so as to be able to swing. That is, a brake operating force corresponding to the operation of the brake pedal 5 is input to the input piston 52 via the input rod 87, and the input piston 52 moves forward according to the input of the brake operating force.

  The elastic body 53 is formed in a cylindrical shape by an elastic material such as rubber so as to have an outer diameter smaller than the inner diameter of the third sliding hole 85 in a natural state where no external force acts. The front end of the guide shaft 88 that passes through 53 is fitted into the front end wall of the third sliding hole 85 in the simulator piston 51. The input piston 52 is provided with a bottomed fourth sliding hole 89 whose front end is opened, and the rear portion of the guide shaft 88 is slidably fitted into the fourth sliding hole 89.

  By the way, an annular liquid chamber 90 is formed between the outer periphery of the elastic body 53 and the inner periphery of the third sliding hole 85, and a communication hole 91 communicating with the annular liquid chamber 90 is provided in the simulator piston 51. In addition, a pair of annular seal members 92 and 93 are mounted on the outer periphery of the simulator piston 51 so as to slidably contact the inner periphery of the sleeve 50 so as to sandwich the communication hole 91 from both sides in the axial direction. Regardless of the movement, the sleeve 50 is provided with a communication hole 94 having an inner end opened on the inner surface of the sleeve 50 between the seal members 92 and 93 and an outer end opened on the outer periphery of the outward flange 50a.

  On the outer periphery of the outward flange portion 50a of the sleeve 50, annular seal members 95, 96 sandwiching the communication hole 94 from both sides are mounted so as to be in sliding contact with the inner periphery of the second cylinder hole 47, and the second casing. 48 is provided with a release port 97 communicating with the communication hole 94. Further, between the annular seal member 57 attached to the rear portion of the backup piston 49 and the annular seal member 95 on the front side of the pair of annular seal members 95, 96 attached to the outer periphery of the outward flange 50a. The second casing 48 is provided with a release hole 98 that opens to the inner surface of the second cylinder hole 47, and this release hole 98 forms a space generated between the backup piston 49, the sleeve 50, and the simulator piston 51. Always communicate with the outside.

  Between the third liquid reservoir chamber 27 of the reservoir R and the release port 97, a pilot-operated on-off valve having a pilot chamber 100 connected to the accumulator chamber 61 of the accumulator 60 via a fourth orifice 99. 101 is interposed. When the hydraulic pressure in the pilot chamber 100 is sufficiently high, the on-off valve 101 opens so that the release port 97 communicates with the third liquid reservoir chamber 27. However, the pump 6 that is a hydraulic pressure generation source is in trouble. When the hydraulic pressure in the pilot chamber 100 decreases, the valve is closed to shut off the release port 97 and the third liquid reservoir chamber 27, and the annular liquid chamber 90 in the stroke simulator 8 is held in a hydraulic pressure locked state. is there. The on-off valve 101 is provided with a hydraulic pressure sensor 102 that detects the hydraulic pressure in the annular liquid chamber 90.

  Incidentally, the operation of the linear solenoid valve 84 in the pressure regulating valve means 7 is controlled in accordance with the brake operation amount of the brake pedal 5, and the detection means 104 for detecting the brake operation amount is attached to the input piston 52, for example. And a pair of electric conductors 106 extending in parallel with the axial direction of the input piston 52 so as to change the sliding contact position of the brush 105 according to the axial movement of the input piston 52, The electric conductors 106 are attached to a support member 107 attached to the rear end of the second casing 48.

  Next, the operation of this embodiment will be described. In the non-brake operation state, the normally open solenoid valve 80 is in the valve open state, and the accumulator 59 is below the set differential pressure required to open the inlet valve 66. The fluid pressure is maintained. In this state, when the brake pedal 5 is depressed and the brake operation is performed, the operation of the pump 6 is started, the input piston 52 moves forward while compressing the elastic body 53, and the inlet valve 66 is accompanied by the depression operation of the brake pedal 5. The valve is opened in response to the mechanical pressing force acting from the simulator piston 51. As a result, the hydraulic pressure is applied to the boost hydraulic chamber 9 and the brake operation of the master cylinder M is started.

  By the way, although the volume of the annular liquid chamber 90 around the elastic body 53 is reduced by the advance of the input piston 52, the on-off valve 101 is opened according to the hydraulic pressure action from the accumulator 59. The pressure in 90 does not increase, and the reaction force acting on the brake pedal 5 at the beginning of depression of the brake pedal 5 is only the elastic force from the elastic body 53.

  Thus, when the pump 6 is operated, the discharge pressure of the pump 6 acts on the boosted hydraulic pressure chamber 9, and when the amount of brake operation by the brake pedal 5 is detected by the detecting means 104, the pressure regulating valve means 7 The linear solenoid valve 84 operates so as to adjust the hydraulic pressure in the boost hydraulic chamber 9 to a hydraulic pressure corresponding to the brake operation amount. At this time, the normally open electromagnetic valve 80 is opened, and the inlet valve 66 is closed as the hydraulic pressure in the boost hydraulic chamber 9 increases.

  In the tandem master cylinder M in accordance with the increase in the hydraulic pressure in the boost hydraulic chamber 9, the rear and front master pistons 10 and 11 move forward against the spring force of the rear and front return springs 19 and 18, The hydraulic pressure generated in the rear and front output hydraulic chambers 15 and 14 is output from the rear and front output ports 33 and 34. That is, the rear part of the master cylinder M and the front master pistons 10 and 11 can be boosted, and the brake fluid pressure thus boosted can be applied to the wheel brakes BA to BD.

  In addition, since the hydraulic pressure generating source is constituted only by the pump 6 and an accumulator using a thick housing is not necessary, the layout to the vehicle body can be improved. An accumulator 59 is connected to the pump 6 via a first one-way valve 78 that prevents the flow of brake fluid to the pump 6 side when the pump 6 is not in operation, and between the boost hydraulic chamber 9 and the accumulator 59, When the hydraulic pressure on the accumulator 59 side becomes higher than the hydraulic pressure on the boost hydraulic pressure chamber 9 side, exceeding the set differential pressure, the valve is opened, and the pressing force that mechanically acts from the brake pedal 5 at the initial stage of braking Since the inlet valve 66 that is opened at is interposed, the inlet valve 66 accumulates a hydraulic pressure equal to or lower than the set differential pressure in the accumulator 59 due to a decrease in the hydraulic pressure in the boost hydraulic pressure chamber 9 during non-brake operation after the brake operation. In the initial stage of brake operation, the inlet valve 66 is opened with a pressing force that acts mechanically from the brake operation member, so that the pressure difference below the set differential pressure from the accumulator 59 is reached. So that the hydraulic pressure is applied to the boosted hydraulic pressure chamber 9 in response to the opening of the inlet valve 66. Therefore, by setting the capacity of the accumulator 59 and the differential pressure, which is the holding pressure of the accumulator 59, to be small enough to initially operate the master cylinder, the accumulator 59 can be improved to the extent that the layout on the vehicle body is improved. A decrease in the boosting response can be avoided while reducing the capacity and weight.

  Further, since the pump 6 is connected to the accumulator 59 through the third orifice 79, it is possible to prevent pulsation from occurring in the hydraulic pressure acting on the accumulator 59 from the pump 6. In addition, a normally-open electromagnetic valve 80 that opens in the brake operation state except for the initial brake operation is interposed between the pump 6 and the accumulator 59. It is led to the accumulator 59, and the hydraulic pressure can be accumulated in the accumulator 59 by closing the inlet valve 66 after the brake operation is completed in response to a decrease in the hydraulic pressure in the boost hydraulic pressure chamber 9. At this time, the hydraulic pressure acting from the pump 6 is accumulated in the accumulator 59 via the first one-way valve 78 and the orifice 79, so that the boosted hydraulic pressure chamber 9 is preferentially given via the second one-way valve 83. Brake fluid can be supplied.

  Further, the pressure regulating valve means 7 permits the flow of brake fluid only from the pump 6 side, a second one-way valve 83 provided between the pump 6 and the boost hydraulic pressure chamber 9, the boost hydraulic pressure chamber 9 and the reservoir. The linear solenoid valve 84 interposed between the R third liquid reservoir chambers 27 and a release valve 103 that opens in response to any operation of the vehicle driver is in parallel with the linear solenoid valve 84. Since it is provided between the chamber 9 and the reservoir R, the pressure regulating valve means 7 can be simply constituted by the second one-way valve 83 and the linear solenoid valve 84, and when the pressure regulating valve means 7 is out of order, the boost hydraulic chamber 9 It can be avoided with a simple configuration that the hydraulic pressure is locked.

  Furthermore, since the linear solenoid valve 84 is a normally closed type and the release valve 103 is a normally closed solenoid valve, the normally closed linear solenoid valve 84 is excited and opened during normal braking operation. It is only necessary to reduce the hydraulic pressure in the boosted hydraulic pressure chamber 9, and the release valve 103 only needs to be kept demagnetized and closed, so that power consumption can be suppressed.

  By the way, when the pump 6 is malfunctioning, the on-off valve 101 is closed, and the annular liquid chamber 90 around the elastic body 53 is in a hydraulic pressure locked state. Therefore, in the stroke simulator 8, the backup piston 49 moves forward against the spring force of the spring 54 together with the input piston 52 in response to the depression of the brake pedal 5, and the fitting protrusion 49 a at the tip of the backup piston 49 is the rear part. The rear master piston 10 is abutted against the master piston 10 and pushed in the forward direction, and the master cylinder M can be operated according to the depression operation of the brake pedal 5 even when the pump 6 is malfunctioning.

  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.

  For example, in the above embodiment, the detection means 104 for detecting the brake operation amount is configured to detect the stroke amount of the input piston 52, but it may be detection of an operation force by a load sensor or the like. Further, although the master cylinder M is configured in a tandem type, a master cylinder of a type in which a single piston is slidably fitted to the casing may be used.

  The release valve 103 may be a manually operated bleeder or a mechanical relief valve instead of the normally closed solenoid valve.

1 is a brake hydraulic pressure system diagram showing an overall configuration of a vehicle brake device. It is a hydraulic circuit diagram which shows the structure of a hydraulic modulator. It is a principal part enlarged view of FIG.

Explanation of symbols

6 ... Pump 7 ... Pressure regulating valve means 9 ... Boost hydraulic chamber 10 ... Master piston 12 ... Casing 59 ... Accumulator 66 ... Inlet valve 78 ... Valve One-way valve 79 ... Orifice 80 ... Normally open solenoid valve 83 that is an on-off valve ... One-way valve 84 ... Linear solenoid valve 103 ... Release valve BA, BB, BC, BD・ Wheel brake M ・ ・ ・ Master cylinder R ・ ・ ・ Reservoir

Claims (5)

  A master cylinder (M) in which a master piston (10) facing the back surface of the boosted hydraulic pressure chamber (9) is slidably accommodated in a casing (12), a reservoir (R), and the reservoir (R) A hydraulic pressure generating source including at least a pump (6) that discharges the brake fluid pumped up, and an output hydraulic pressure of the hydraulic pressure generating source according to a brake operation input from the brake operating member (5) A vehicular brake device comprising pressure regulating valve means (7) for acting on a hydraulic pressure chamber (9), wherein the master cylinder (M) is connected to a wheel brake (BA, BB, BC, BD); The pressure generating source is composed only of the pump (6), and at least when the pump (6) is not in operation, the pump (6) is connected via a valve (78) that blocks the flow of brake fluid toward the pump (6). ) Accumulator ( 9) is connected, and the hydraulic pressure on the accumulator (59) side is set higher than the hydraulic pressure on the boost hydraulic pressure chamber (9) side between the boost hydraulic pressure chamber (9) and the accumulator (59). And an inlet valve (66) that is opened by a pressing force that mechanically acts from the brake operating member (5) at the initial stage of braking operation is provided. Brake device for vehicles.   The vehicle brake device according to claim 1, characterized in that the pump (6) is connected to the accumulator (59) via an orifice (79).   3. The vehicle according to claim 1, wherein an on-off valve (80) is provided between the pump (6) and the accumulator (59), which opens in a brake operation state excluding an initial brake operation. Brake device.   The one-way valve (83) provided between the pump (6) and the boosted hydraulic pressure chamber (9), the pressure regulating valve means (7) allowing only the flow of brake fluid from the pump (6) side. ) And a linear solenoid valve (84) interposed between the boost hydraulic chamber (9) and the reservoir (R), and a release valve (opening in response to an arbitrary operation of the vehicle driver) 103) is provided between the boost hydraulic chamber (9) and the reservoir (R) in parallel with the linear solenoid valve (84). Brake device.   The vehicle brake device according to claim 4, wherein the linear solenoid valve (84) is a normally closed type, and the release valve (103) is a normally closed type electromagnetic valve.

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