JP4922111B2 - Brake hydraulic control device for vehicle - Google Patents

Description

The present invention relates to an improvement in a brake hydraulic control device for a vehicle including a plunger pump that includes a cylinder and a single plunger that is reciprocally fitted in a cylinder bore of the cylinder.

Such a plunger-type pump is already known as disclosed in Patent Document 1, and such a vehicle brake hydraulic control device is disclosed in Patent Document 2.
JP 2006-183619 A JP 2001-63542 A

  The conventional plunger type pump has only one suction port for one discharge port. Therefore, the fluid is sucked from two independent low-pressure channels and discharged to one or two high-pressure channels. In this case, since two plungers that operate individually are required, it is not possible to avoid the increase in size and cost of the pump.

The present invention has been made in view of such circumstances. By reciprocating a single plunger, fluid is sucked from two independent suction ports and discharged to two independent discharge ports. possible to, by using an inexpensive plunger pump structure simple and compact, and purpose thereof is to provide a vehicle brake hydraulic pressure control apparatus capable of simplifying the hydraulic circuit.

In order to achieve the above object , the present invention provides an input oil passage connected to a master cylinder, a cut valve for opening and closing the input oil passage, an output oil passage connected to a wheel brake, a reservoir capable of absorbing hydraulic oil, A pressure increasing state in which the input oil passage and the output oil passage are communicated and the output oil passage and the reservoir are shut off, a pressure reducing state in which the input oil passage and the output oil passage are shut off and the output oil passage and the reservoir are communicated, and Brake hydraulic control valve means that can switch the hydraulic pressure holding state that shuts off both the input oil path and the reservoir and output oil path, and the hydraulic oil absorbed in the reservoir is sucked in through the decompression oil path or operated from the master cylinder A hydraulic pump for sucking oil through the suction oil passage, a boost oil passage for guiding the discharge hydraulic pressure of the hydraulic pump to the input oil passage downstream from the cut valve, a brake hydraulic control valve means and And a electronic control unit for controlling the cut valve, a plunger provided in the brake pressure control apparatus for a vehicle, said hydraulic pump, a cylinder, a single plunger is reciprocably fitted in the cylinder bore of the cylinder together comprise a formula pump, in its cylinder, the volume is increased or decreased by the reciprocation of the plunger, a first and a second pump chamber which is independent, the first suction valve and the first discharge valve to the first pump chamber A first suction port and a first discharge port that are connected to each other via a second suction port, and a second suction port and a second discharge port that are connected to the second pump chamber via a second suction valve and a second discharge valve, respectively. the provided wherein the first suction port, while for constantly communicating the reservoir via the pressure reducing fluid passage, wherein the second suction port, and blocked from said vacuum oil passage Via the serial suction oil passage is communicated constantly communicating the output port of the master cylinder, the first and that was connected to the booster fluid passage in parallel with each other both of the second discharge port a first feature, and this feature In addition, a plug body that prevents axial movement of the cylinder in the body is fixed to the body in which the cylinder is fitted, and the plug body includes a single body that faces the end wall of the cylinder. A discharge chamber and a final discharge port for communicating the discharge chamber with the boost oil passage are formed, and the first and second discharge ports are provided in the cylinder so that both communicate with the discharge chamber in parallel. This is the second feature.

According to the present invention , by operating the independent first and second pump chambers by the reciprocating motion of a single plunger, the first and second pump chambers individually draw fluid from the first and second suction ports. A single plunger pump that can be sucked and discharged to the first and second discharge ports , has a simple structure , is small, and is inexpensive, can be used as the hydraulic pump.

In addition, during the anti-lock control, this single hydraulic pump sucks the brake oil absorbed in the reservoir through the pressure reducing oil passage and returns it to the input oil passage through the pressure increasing oil passage by the operation of the first pump chamber. A second pump that exhibits the first pump function and supplies the hydraulic oil sucked from the master cylinder through the suction oil passage to the wheel brake through the boost oil passage and the output oil passage by the operation of the second pump chamber during the automatic brake control. The pump function can be demonstrated. At that time, the first and second discharge valves prevent the discharge oil of one of the first and second pump chambers from flowing back to the other, thereby preventing communication between the decompression oil passage and the suction oil passage. Therefore, the suction valve that closes the suction oil passage and the check valve that prevents the leakage of hydraulic oil from the decompression oil passage to the reservoir during normal braking, as in the conventional device, are unnecessary, and the hydraulic circuit can be simplified. Can do.

  Embodiments of the present invention will be described based on one embodiment of the present invention shown in the accompanying drawings.

  FIG. 1 is a hydraulic circuit diagram of a front wheel drive type automobile brake device equipped with a brake hydraulic pressure control device of the present invention, and FIG. 2 is an enlarged vertical sectional view of a hydraulic pump in the brake hydraulic pressure control device.

  First, in FIG. 1, the master cylinder M is configured in a tandem type having a pair of front and rear first and second output ports 1a and 1b that output brake hydraulic pressure in response to an input applied from a brake pedal P to a piston. The first and second input oil passages 2a and 2b individually connected to the first and second output ports 1a and 1b, the left front wheel wheel brake Ba, the right rear wheel wheel brake Bb, and the right front wheel brake The modulator 3 is interposed between the first to fourth output oil passages 12a to 12d individually provided for Bc and the left rear wheel brake Bd.

  The modulator 3 includes brake control valve means 4. The brake control valve means 4 includes first to fourth inlet valves 5a individually corresponding to the left front wheel brake Ba, the right rear wheel brake Bb, the right front wheel brake Bc, and the left rear wheel brake Bd, respectively. And 5d, and first to fourth outlet valves 6a to 6d individually corresponding to the respective wheel brakes Ba to Bd. Each of the inlet valves 5a to 5d is a normally open solenoid valve, and Each of the outlet valves 6a to 6d is a normally closed electromagnetic valve. The first input oil passage 2a is connected to the inlets of the first and second inlet valves 5a and 5b, and the second input oil passage 2b is connected to the inlets of the third and fourth inlet valves 5c and 5d. A first output oil passage 12a is provided at the outlet of the first inlet valve 5a and the inlet of the first outlet valve 6a. A second output oil passage 12b is provided at the outlet of the second inlet valve 5b and the inlet of the second outlet valve 6b. The third output oil passage 12c is connected to the outlet of the third inlet 5c and the inlet of the third outlet valve 6c, and the fourth output oil passage 12d is connected to the outlet of the fourth inlet valve 5d and the inlet of the fourth outlet valve 6d.

  First and second hydraulic pumps 8a and 8b driven by a common electric motor 17 are provided. Each of the hydraulic pumps 8a and 8b includes a pair of first and second suction ports 41 and 42, and a pair of first and second suction pumps. It has the 2nd discharge ports 54 and 55 and the single final discharge port 62 connected to these both discharge ports 54 and 55, and the exit of the 1st and 2nd outlet valves 6a and 6b is the 1st decompression oil. The first hydraulic pump 8a of the first hydraulic pump 8a is connected to the first suction port 41 via the path 7a, and the outlets of the third and fourth outlet valves 6c, 6d are second via the second pressure reducing oil path 7b. The first and second reservoirs 9a and 9b are connected to the first suction port 41 of the hydraulic pump 8b, and the first and second decompression oil passages 7a and 7b, respectively.

  The final discharge port 62 of the first hydraulic pump 8a is connected to the first input oil passage 2a via the first boost oil passage 11a, and the final discharge port 62 of the second hydraulic pump 8b passes through the second boost oil passage 11b. To the second input oil passage 2b. Further, an orifice 10 and a damper 13 for absorbing pulsation of the discharge pressure of the corresponding hydraulic pumps 8a and 8b are connected to the first and second pressure increasing oil passages 11a and 11b.

  The first and second input oil passages 2a and 2b are provided with a cut valve 14 consisting of a normally open solenoid valve upstream from the connection point of the first and second pressure increase oil passages 11a and 11b.

  A first suction oil passage 15a branched from the first input oil passage 2a upstream of the cut valve 14 is connected to the second suction port 42 of the first hydraulic pump 8a, and the second suction port of the second hydraulic pump 8b. A second suction oil passage 15b branched from the second input oil passage 2a upstream of the cut valve 14 is connected to 42.

  The first input oil passage 2a or the second input oil passage 2b is connected to a hydraulic pressure sensor 21 (master cylinder operating state detection means) that detects the output hydraulic pressure of the master cylinder M and outputs a signal corresponding thereto. Is input to the electronic control unit 20. In addition to the hydraulic pressure sensor 21, the electronic control unit 20 includes a wheel speed sensor 22 that detects the rotational speed of each wheel, a steering angle sensor 23 that detects the steering angle of the steering handle, and a yaw rate sensor that detects the yaw rate of the vehicle. 24, a detection signal from a radar 25 or the like for detecting the distance to an obstacle ahead of the vehicle is input, the signals are calculated, and each part of the brake control valve means 4 and 4 is controlled.

  Next, the first and second hydraulic pumps 8a and 8b will be described with reference to FIG.

  Since the first and second hydraulic pumps 8a and 8b are symmetrically configured with the cam shaft 30 driven to rotate by the electric motor 17, only the first hydraulic pump 8a will be described in detail.

  The body 3 a of the modulator 3 is provided with a stepped hole 31 extending in the radial direction of the cam shaft 30. The stepped hole 31 includes a small diameter hole 31a having one end opened on the camshaft 30 side, and a large diameter hole 31b connected to the other end of the small diameter hole 31a via an annular step portion 31c. A cylinder 32 having a stepped outer peripheral surface shape corresponding to the stepped hole 31 is fitted into the stepped hole 31, and a stepped portion 32c formed in the middle of the cylinder 32 is disposed so as to contact the annular stepped portion 31c. Is done. A retainer 33 is fitted to an end portion of the cylinder 32 on the large diameter side, and a plug body 34 that prevents the cylinder 32 from moving in the axial direction is fitted to the large diameter hole 31 b via the retainer 33. Is fixed to the body 3 a by a retaining ring 35.

  The cylinder 32 is provided with a stepped cylinder bore 36. The stepped cylinder bore 36 is provided with a large-diameter bore portion 36a having one end opened on the camshaft 30 side, and a bottomed small-diameter bore portion 36b concentrically connected to the other end of the large-diameter bore portion 36a. A single plunger 37 is slidably fitted to the large-diameter and small-diameter bore portions 36a, 36b. The plunger 37 is integrally formed with a large-diameter plunger portion 37a that is slidably fitted to the large-diameter bore portion 36a and a small-diameter plunger portion 37b that is slidably fitted to the small-diameter bore portion 36b. Thus, the end surface of the large-diameter plunger portion 37 a is disposed so as to contact the outer peripheral surface of the cam shaft 30.

  An annular shoulder portion 37c is formed between the large and small diameter plunger portions 37a and 37b, and a first portion 36c is formed between the shoulder portion 37c and a step portion 36c between the large and small diameter bore portions 36a and 36b of the cylinder 32. A pump chamber 38 is defined. A second pump chamber 39 is defined between the end surface of the small diameter plunger 37b and the bottom surface of the small diameter bore portion 36b. The first pump chamber 38 accommodates a return spring 40 that constantly urges the plunger 37 in the direction of contact with the camshaft 30, and cooperates with the push-up force of the rotating camshaft 30 and the return force of the return spring 40. By the action, the plunger 37 is reciprocated in the axial direction. The first and second pump chambers 38 and 39 increase or decrease the volume according to the reciprocation of the plunger 37.

  The cylinder 32 and the plunger 37 are provided with a series of first suction ports 41 that open to the first pump chamber 38, and the decompression oil passage 7 a is connected to the first suction ports 41. A first suction valve 43 is provided in the middle of the first suction port 41. The first suction valve 43 includes a cylindrical valve seat member 45 mounted in the plunger 37, a ball valve body 47 for opening and closing the valve hole 46 of the valve seat member 45, and the ball valve body 47 in the closing direction. It is comprised with the valve spring 48 to urge. Thus, the ball valve body 47 is opened when the first pump chamber 38 is depressurized.

  The cylinder 32 and the plunger 37 are provided with a series of second suction ports 42 that open to the second pump chamber 39, and the first suction oil passage 15 a is connected to the second suction ports 42. A second suction valve 44 is provided in the middle of the second suction port 42. The second intake valve 44 includes a cylindrical valve seat member 49 mounted in the plunger 37, a ball valve body 51 for opening and closing the valve hole 50 of the valve seat member 49, and the ball valve body 51 in the closing direction. And a biasing valve spring 52. Thus, the ball valve body 51 is opened when the second pump chamber 39 is depressurized.

  The stopper 34 is formed with a discharge chamber 53 facing the retainer 33, and a series of first discharge ports 54 communicating with the first pump chamber 38 are provided in the plunger 37 and the retainer 33. A first discharge valve 71 is provided in the middle of the first discharge port 54. The first discharge port 54 includes a valve seat 56 formed in the middle of the first discharge port 54, a ball valve body 57 seated on the valve seat 56, and a biasing force of the ball valve body 57 toward the valve seat 56. The fixed end of the valve spring 58 is supported by the retainer 33. Thus, the ball valve body 57 is opened when the pressure of the first pump chamber 38 is increased.

  A series of second discharge ports 55 that communicate with the discharge chamber 53 in the second pump chamber 39 are provided in the plunger 37 and the retainer 33, and a second discharge valve 72 is provided in the middle of the second discharge port 55. The second discharge valve 72 includes a valve seat 59 formed in the middle of the second discharge port 55, a ball valve body 60 seated on the valve seat 59, and a biasing force of the ball valve body 60 toward the valve seat 59. The fixed end of the valve spring 61 is also supported by the retainer 33. Thus, the ball valve body 60 is also opened when the pressure of the second pump chamber 39 is increased.

  The plug body 34 is provided with a plurality of final discharge ports 62 that open to the discharge chamber 53, and the first pressure increase oil passage 11 a is connected to the final discharge port 62. In FIG. 2, reference numerals 63 to 69 denote seal members.

Next, the operation of this embodiment will be described.
[Normal brake]
During normal braking in which each wheel is not likely to lock, each inlet valve 5a to 5d is demagnetized and opened, and each outlet valve 6a to 6d is also demagnetized and closed. . Now, when the master cylinder M is operated by depressing the brake pedal P, the output hydraulic pressure from the first output port 1a is the first input oil passage 2a, the cut valve 14, the first and second inlet valves 5a, 5b and the first. The second output oil passages 12a and 12b are supplied to the left front wheel brake Ba and the right rear wheel brake Bb to operate them. The output hydraulic pressure from the second output port 1b is for the right front wheel via the second input oil passage 2b, the cut valve 14, the third and fourth inlet valves 5c and 5d, and the third and fourth output oil passages 12c and 12d. It is supplied to the wheel brake Bc and the wheel brake Bd for the left rear wheel and operates them.

  In this case, the output hydraulic pressure of the first and second output ports 1a and 1b is also transmitted to the first and second suction oil passages 15a and 15b, but the second suction valves of the hydraulic pumps 8a and 8b to which the hydraulic pressure corresponds. 44 opens into the second pump chamber 39, then opens the second discharge valve 72 and moves to the discharge chamber 53 and acts on the first discharge valve 71. The direction of action of the hydraulic pressure is that of the first discharge valve 71. Since the valve is in the valve closing direction, the first discharge valve 71 continues to hold the valve closed state, and the first and second suction oil passages 15a and 15b to the first and second decompression oil passages 7a and 7b, that is, the first 1. Leakage of hydraulic pressure to the second reservoirs 9a and 9b can be prevented. Therefore, it is not necessary to provide the suction valve 16a and the check valve 10 as described in Patent Document 2, which can contribute to reduction of the number of parts and simplification of the hydraulic circuit.

The hydraulic pressure transmitted to the discharge chambers 53 of the first and second hydraulic pumps 8a and 8b is transmitted to the first and second boost oil passages 11a and 11b. As described above, the first and second input oil passages 2a are transmitted. , 2b also acts on the downstream ends of the first and second boost oil passages 11a, 11b, so that no hydraulic oil flows in the first and second boost oil passages 11a, 11b.
[Anti-lock control]
When the wheel is about to enter the locked state at the time of braking, the electronic control unit 20 activates the inlet valve corresponding to the wheel that is about to be locked among the first to fourth inlet valves 5a to 5d. While closing the valve, the outlet valve corresponding to the wheel among the first to fourth outlet valves 6a to 6d is excited and opened. Then, a part of the hydraulic pressure of the wheel brake corresponding to the wheel is absorbed by the first reservoir 9a or the second reservoir 9b through the corresponding outlet valve and the corresponding decompression oil passages 7a and 7b, and the wheel. The brake hydraulic pressure is reduced.

  In order to keep the wheel brake hydraulic pressure constant, the inlet valves 5a to 5d corresponding to the wheel brake may be excited and closed, and the outlet valves 6a to 6d may be demagnetized to be closed. When the brake hydraulic pressure is increased, the inlet valves 5a to 5d are demagnetized and opened, and the outlet valves 6a to 6d are demagnetized and closed. By controlling in this way, it is possible to brake efficiently without locking the wheels.

  During such anti-lock control, the electronic control unit 20 energizes the electric motor 17 to rotationally drive the camshaft 30 and reciprocate the plungers 37 of the first and second hydraulic pumps 8a and 8b. 2 Increase or decrease the volume of the pump chambers 38 and 39. Thus, in the first pump chamber 38, when the pressure is reduced, the brake oil absorbed in the first and second reservoirs 9a and 9b is sucked through the first and second pressure reducing oil passages 7a and 7b, and the pressure is increased. Sometimes the oil is discharged into the discharge chamber 53, and the brake oil is returned to the first and second input oil passages 2a and 2b through the first and second pressure increase oil passages 11a and 11b. By this recirculation, an increase in the depression amount of the brake pedal P due to the absorption of the brake oil in the reservoirs 9a and 9b is suppressed.

In the second pump chamber 39, the hydraulic oil in the first and second suction oil passages 15a and 15b is sucked when the pressure is reduced, and is discharged into the discharge chamber 53 when the pressure is increased. Part of the oil that has moved to the second boost oil passages 11a and 11b circulates from the first and second input oil passages 2a and 2b to the first and second suction oil passages 15a and 15b.
[Automatic brake control 1 (traction control)]
For example, when the front wheel that is the driving wheel is likely to run idle when the vehicle starts, the electronic control unit 20 calculates the rotation difference between the front wheel and the rear wheel from the signal sent from the wheel speed sensor 22 of each wheel, and the rotation difference. Is determined to be in the idling state, the cut valve 14, the second inlet valve 5b and the fourth inlet valve 5d are excited and closed, and the electric motor 17 is operated to rotate the camshaft 30. The plungers 37 of the first and second hydraulic pumps 8a and 8b are reciprocated to increase or decrease the volumes of the first and second pump chambers 38 and 39. In this case, in particular, by the operation of the second pump chamber 39, the hydraulic oil of the master cylinder M is sucked from the first and second output ports 1a and 1b through the first and second suction oil passages 15a and 15b, and the first , Supply to the left and right front wheel brakes Ba, Bc through the second boost oil passages 11a, 11b, the first and third inlet valves 5a, 5c, and the flow of the hydraulic oil to the master cylinder M side is closed Therefore, it is possible to automatically prevent idling of the front wheels by operating the left and right front wheel brakes Ba, Bc.

At that time, when the oil pressures of the front wheel brakes Ba and Bc are kept constant, the inlet valves 5a to 5d are excited and closed, and the outlet valves 6a to 6d are demagnetized as in the anti-lock control. In order to increase the brake hydraulic pressure, the inlet valves 5a to 5d are demagnetized and opened, and the outlet valves 6a to 6d are demagnetized and returned to the closed state. By doing so, it is possible to prevent the front wheels from slipping and to control the driving torque appropriately.
[Automatic brake control 2 (brake assist)]
When the master cylinder M is actuated by depressing the brake pedal P, the hydraulic sensor 21 detects the master cylinder output hydraulic pressure and outputs a corresponding signal to the electronic control unit 20. The output boost speed of M is calculated, and when the boost speed exceeds a specified threshold value, it is determined that the sudden braking operation is being performed, the electric motor 17 is operated, and the first and second hydraulic pumps 8a and 8b are driven. At the same time, the cut valve 14 is excited to close. As a result, the first and second pump chambers 38 and 39 of the first and second hydraulic pumps 8a and 8b are operated. In this case, the first and second input oil passages 2a are particularly operated by the operation of the second pump chamber 39. , 2b, the hydraulic pressure of the master cylinder M is sucked through the first and second suction oil passages 15a, 15b, the pressure is increased, and the wheels are passed through the pressure-increasing oil passages 11a, 11b through the open inlet valves 4a-4d. Since the pressure is fed to the brakes Ba to Bd, they can be operated strongly and can respond to a sudden braking operation.
[Automatic brake control 3 (vehicle running attitude control)]
When the vehicle is turning left, for example, the output signals of the rudder angle sensor 23 and the yaw rate sensor 24 do not correspond to each other, and the electronic control unit 20 determines that the vehicle is about to turn left, for example, excessively. In order to correct the direction, the control unit 20 operates the electric motor 17 to drive the first and second hydraulic pumps 8a and 8b, and the cut valve 14, the first inlet valve 5a, and the fourth inlet valve 5d. To close the valve. As a result, the first and second pump chambers 38 and 39 of the first and second hydraulic pumps 8a and 8b are operated. In this case, the hydraulic oil in the master cylinder M is first supplied by the operation of the second pump chamber 39 in particular. , Suction through the first suction oil passage 15a from the second output ports 1a, 1b, and through the pressure increase oil passages 11a, 11b, the second and third inlet valves 5b, 5c, the right front wheel brake Bc and the right rear wheel. Since only the brake Bb is supplied and the flow of the hydraulic oil to the master cylinder M side is blocked by the closed cut valve 14, the right front wheel brake Bc and the right rear wheel brake Bb are operated. The traveling posture of the vehicle can be corrected to the right side so as to correspond to the steering angle.

  In order to correct the vehicle direction to the left side, the second inlet valve 5b and the third inlet valve 5c are excited and closed in the opposite direction, and the discharge hydraulic pressures of the first and second hydraulic pumps 8a and 8b are closed. Is supplied only to the left front wheel brake Ba and the left rear wheel brake Bd through the first and fourth inlet valves 5a and 5d, and they are operated.

Further, whether the vehicle is turning right or straight, the traveling posture of the vehicle is controlled by the same action as described above.
[Automatic brake control 4 (vehicle rear-end collision prevention control)]
While the vehicle is traveling, the radar 25 detects the relative speed and distance with respect to the preceding vehicle, and if the electronic control unit 20 determines that there is a possibility of a rear-end collision based on the information, the electronic control unit 20 activates the electric motor 17. Then, the first and second hydraulic pumps 8a and 8b are driven and the cut valve 14 is excited to close. As a result, the first and second pump chambers 38 and 39 of the first and second hydraulic pumps 8a and 8b are operated. In this case, the hydraulic oil in the master cylinder M is first supplied by the operation of the second pump chamber 39 in particular. , The air is sucked through the second suction oil passages 15a and 15b, and the pressure is increased and pressure-fed from the pressure-up oil passages 11a and 11b to the respective wheel brakes Ba to Bd through the opened inlet valves 4a to 4d. It is possible to prevent the rear-end collision in advance.

  When the master cylinder M is operated by depressing the brake pedal P during the above automatic brake control 1 to 4, the hydraulic pressure sensor 21 receives the output hydraulic pressure and inputs a detection signal to the electronic control unit 20. Upon receiving the signal, the electronic control unit 20 stops the operation of the electric motor 17 so as to prohibit the automatic brake control, the cut valve 14 is normally opened, and all the inlet valves 5a to 5d are normally operated. In addition, all the outlet valves 6a to 6d are returned to the normal closed state. Therefore, as in the case of the normal braking, the output hydraulic pressure of the master cylinder M is supplied to all the wheel brakes Ba to Bd and can be operated.

  The present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the invention. For example, the present invention can be applied to a rear wheel drive vehicle.

The hydraulic circuit diagram of the brake device for front-wheel drive type vehicles provided with the brake oil pressure control device of the present invention. The expanded longitudinal cross-sectional view of the hydraulic pump in the said brake hydraulic control apparatus.

Ba to Bd ··· wheel brake M ··· master cylinders 2a and 2b ··· input oil passage 4 ··· brake control valve means 8a and 8b ··· hydraulic pumps 9a and 9b ··· · Reservoirs 11a, 11b · · Pressure oil passages 12a, 12b · · · Output oil passage 14 · · · Cut valves 15a and 15b · · · Suction oil passage 32 · · · cylinder 36 · · · cylinder bore 37 · · · plunger 38 · · First pump chamber 39 ... second pump chamber 41 ... first suction port 42 ... second suction port 43 ... first suction valve 44 ... second suction valve 54 ... second 1 discharge port 55 ... 2nd discharge port 71 ... 1st discharge valve 72 ... 2nd discharge valve

Claims (2)

Input oil passage leading to the master cylinder (M) and (2a, 2b), and the input oil passage (2a, 2b) cut valve for opening and closing (14), the output oil passage leading to the wheel brake (Ba to Bd) ( 12a-12d), reservoirs (9a, 9b) capable of absorbing hydraulic oil, and the input oil passages (2a, 2b) and the output oil passages (12a-12d) and the output oil passages (12a-12d) And an increased pressure state that shuts off between the reservoirs (9a, 9b), shuts off between the input oil passages (2a, 2b) and the output oil passages (12a-12d) and outputs the oil passages (12a-12d) and the reservoirs (9a, 9b) 9b) Brake hydraulic pressure capable of switching between a reduced pressure state communicating with each other and a hydraulic pressure holding state for blocking both the input oil passages (2a, 2b) and the reservoirs (9a, 9b) and the output oil passages (12a-12d). Control valve means (4); Hydraulic pump that sucks hydraulic oil absorbed by the servers (9a, 9b) through the decompression oil passages (7a, 7b) and sucks hydraulic oil from the master cylinder (M) through the suction oil passages (15a, 15b). (8a, 8b), a boosting oil passage (11a, 11b) for guiding the discharge hydraulic pressure of the hydraulic pump (8a, 8b) to the input oil passage (2a, 2b) downstream from the cut valve (14), and a brake In a vehicle brake hydraulic pressure control device comprising a hydraulic control valve means (4) and an electronic control unit (20) for controlling a cut valve (14),
The hydraulic pump (8a, 8b) is constituted by a plunger-type pump including a cylinder (32) and a single plunger (37) fitted in a cylinder bore (36) of the cylinder (32) so as to reciprocate. In addition, the cylinder (32) includes first and second pump chambers (38, 39) each having a volume that increases and decreases due to reciprocation of the plunger (37), and the first pump chamber (38). The first suction port (41) and the first discharge port (54) connected to the first pump through the first suction valve (43) and the first discharge valve (71), respectively, and the second pump chamber (39). A second suction port (42) and a second discharge port (55) connected via two suction valves (44) and a second discharge valve (72), respectively;
Wherein the first suction port (41), said reduced pressure fluid passage (7a, 7b) the reservoir (9a, 9b) through one to constantly communicating, to the second suction port (42), said vacuum oil The output ports (1a, 1b) of the master cylinder (M) are always in communication via the suction oil passages (15a, 15b) cut off from the passages (7a, 7b), and the first and second discharge ports (54 , 55) are connected to the boost oil passages (11a, 11b) in parallel with each other . A plug (34) that prevents the cylinder (32) from moving in the axial direction within the body (3a) is fixed to the body (3a) fitted with the cylinder (32). ) Includes a single discharge chamber (53) that faces the end wall of the cylinder (32), and a final discharge port (62) that communicates the discharge chamber (53) with the pressurized oil passage (11a, 11b). The first and second discharge ports (54, 55) are provided in the cylinder (32) such that both communicate with the discharge chamber (53) in parallel. The brake hydraulic control device for a vehicle according to 1.

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