JP2009068376A - Plunger type pump, and hydraulic control device for vehicle brake with the pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small and inexpensive plunger type pump with a simple structure by enabling sucking of a fluid from two independent suction ports and discharging thereof to two independent discharge ports by reciprocation of a single plunger. <P>SOLUTION: This plunger type pump is provided with a cylinder 32 and the single plunger 37 fitted in the cylinder bore 36 of this cylinder 32 in a reciprocating manner. The cylinder 32 is provided with first and second pump chambers 38, 39 independent respectively having their volumes increased/decreased by reciprocation of the plunger 37, the first suction port 41 and the first discharge port 54 connected to the first pump chamber 38 respectively via a first suction valve 43 and a first discharge valve 71, and the second suction port 42 and the second discharge port 55 connected to the second pump chamber 39 respectively via a second suction valve 44 and a second discharge valve 72. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a plunger-type pump including a cylinder and a single plunger that is fitted in a cylinder bore of the cylinder so as to be reciprocally movable, and to an improvement in a vehicle brake hydraulic control device including the pump.

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

  The conventional plunger type pump has only one suction port for one discharge port, and therefore sucks fluid from two independent low-pressure channels and discharges it to one or two high-pressure channels. In this case, since two plungers that operate individually were required, it was 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. A first object of the present invention is to provide a plunger pump that is simple in structure, small and inexpensive, and provides a brake hydraulic control device for a vehicle that can simplify a hydraulic circuit by using the pump. This is the second purpose.

  In order to achieve the above object, the present invention provides a plunger pump comprising a cylinder and a single plunger that is fitted in a cylinder bore of the cylinder so as to be reciprocally movable. The first and second pump chambers independent of each other, the first suction port and the first discharge port connected to the first pump chamber via the first suction valve and the first discharge valve, respectively, A first feature is that a second suction port and a second discharge port connected to the second pump chamber via a second suction valve and a second discharge valve, respectively, are provided.

  The present invention also includes an input oil passage connected to the master cylinder, a cut valve for opening and closing the input oil passage, an output oil passage connected to the wheel brake, a reservoir capable of absorbing hydraulic oil, an input oil passage and an output oil passage. Pressure increase state that communicates with each other and shuts off between the output oil passage and the reservoir, pressure reduction state that shuts off between the input oil passage and the output oil passage and communicates between the output oil passage and the reservoir, and the input oil passage, reservoir, and output Brake hydraulic control valve means that can switch the hydraulic pressure holding state that shuts off both of the oil path and the hydraulic oil absorbed by the reservoir is sucked through the pressure reducing oil path, or hydraulic oil from the master cylinder is sucked through the suction oil path Hydraulic pressure pump, a boost oil passage for guiding the discharge hydraulic pressure of the hydraulic pump to an input oil passage downstream of the cut valve, a brake hydraulic control valve means and an electric power for controlling the cut valve. In the brake hydraulic control apparatus for a vehicle having a control unit, the hydraulic pump is composed of a cylinder and a single plunger that is reciprocally fitted to a cylinder bore of the cylinder. The first and second pump chambers, each of which increases or decreases in volume due to the reciprocation of the plunger, and a first suction port connected to the first pump chamber via a first suction valve and a first discharge valve, respectively A first discharge port and a second suction port and a second discharge port connected to the second pump chamber via a second suction valve and a second discharge valve, respectively, are provided, and the reservoir communicates with the first suction port. The second feature is that a suction oil passage is connected to the second suction port, and a boost oil passage is connected to both the first and second discharge ports.

  According to the first feature of the present invention, the first and second pump chambers are operated as the first and second suction ports by operating the independent first and second pump chambers by reciprocating movement of a single plunger. Thus, a plunger type pump can be provided which can suck a fluid individually and discharge it to the first and second discharge ports, has a simple structure, is small, and is inexpensive.

  According to the second feature of the present invention, during the anti-lock control, the single hydraulic pump sucks the brake oil absorbed in the reservoir through the decompression oil passage and pressurizes it by the operation of the first pump chamber. The first pump function that recirculates to the input oil passage through the oil passage is demonstrated, and at the time of automatic brake control, the hydraulic oil sucked from the master cylinder through the suction oil passage is operated by the operation of the second pump chamber. The second pump function for supplying the wheel brake through the road can be exhibited. 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 during normal braking and the check valve that prevents the leakage of hydraulic oil from the decompression oil passage to the reservoir during normal braking are not required, and the hydraulic circuit can be simplified. Can do.

  Embodiments of the present invention will be described based on an 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 longitudinal 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, 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 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 a left front wheel brake Bb, a right rear wheel brake Bb, a right front wheel brake Bc, and a left rear wheel brake Bd, respectively. To 5d, and first to fourth outlet valves 6a to 6d individually corresponding to the respective wheel brakes Ba to Bd, and each of the inlet valves 5a to 5d is a normally open solenoid valve, 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 decompression 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 electromagnetic 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 from 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. The second suction oil passage 15 b branched from the second input oil passage 2 a upstream of the cut valve 14 is connected to 42.

  Connected to the first input oil passage 2a or the second input oil passage 2b is an oil pressure sensor 21 (master cylinder operating state detection means) that detects the output oil 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, detection signals from a radar 25 or the like for detecting the distance to an obstacle ahead of the vehicle are input, and these signals are calculated to control each part of the brake control valve means 4 and 4.

  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. In this stepped hole 31, a cylinder 32 having a corresponding stepped outer peripheral surface shape is fitted, 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 the end 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 into the large diameter hole 31b 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 coaxially 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 formed by integrally forming a large-diameter plunger portion 37a slidably fitted to the large-diameter bore portion 36a and a small-diameter plunger portion 37b 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 by 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 plug body 34 has a discharge chamber 53 facing the retainer 33, and a series of first discharge ports 54 communicating with the discharge chamber 53 through 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 urges 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 element 57 is opened when the pressure of the first pump chamber 38 is increased.

  A series of second discharge ports 55 communicating with the second pump chamber 39 to the discharge chamber 53 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 urges 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. , Are supplied to the left front wheel wheel brake Ba and the right rear wheel wheel brake Bb via the second output oil passages 12a and 12b, and 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. The brakes are supplied to the wheel brake Bc and the left rear wheel brake Bd to operate 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 intake valves of the hydraulic pumps 8a and 8b to which the hydraulic pressure corresponds. 44 is opened to enter the second pump chamber 39, then the second discharge valve 72 is opened and moved to the discharge chamber 53 to act on the first discharge valve 71. The direction of the action of the hydraulic pressure is the same as that of the first discharge valve 71. Since the valve is in the valve closing direction, the first discharge valve 71 continues to maintain 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 hydraulic pressure leakage to the first and 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 the reduction in the number of parts and the 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 pressure increase oil passages 11a and 11b, but as described above, the first and second input oil passages 2a. , 2b 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 into 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 may be demagnetized and opened, and the outlet valves 6a to 6d may be demagnetized and closed. By controlling in this way, braking can be performed efficiently without locking the wheels.

  During such antilock 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 , The second pressure increasing oil passages 11a, 11b, the first and third inlet valves 5a, 5c are supplied to the left and right front wheel brakes Ba, Bc, and the flow of the hydraulic oil to the master cylinder M side is closed. Therefore, the left and right front wheel brakes Ba and Bc can be operated to automatically prevent the front wheels from slipping.

At that time, when the oil pressure of the front wheel brakes Ba and Bc is kept constant, the inlet valves 5a to 5d are energized 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. Thus, 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 signal corresponding thereto to the electronic control unit 20. The output boosting speed of M is calculated, and when the boosting speed exceeds a specified threshold value, it is determined that a sudden braking operation is being performed, and the electric motor 17 is operated to drive the first and second hydraulic pumps 8a and 8b. At the same time, the cut valve 14 is excited and closed. 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, in particular, the first and second input oil passages 2a are 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, and the pressure is increased to increase the pressure from the pressure increase oil passages 11a, 11b to the open 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. The control unit 20 operates the electric motor 17 to correct the direction and drives the first and second hydraulic pumps 8a and 8b, as well as 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, particularly, the operation of the second pump chamber 39 causes the hydraulic oil in the master cylinder M to be supplied to the first. , Through the first suction oil passage 15a from the second output ports 1a, 1b, and through the boost 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 vehicle's running posture can be corrected to the right so as to correspond to the rudder 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 reversed. Are supplied only to the left front wheel brake Ba and the left rear wheel brake Bd through the first and fourth inlet valves 5a, 5d, and operate them.

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 when the electronic control unit 20 determines that there is a possibility of a rear-end collision based on the detected 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, particularly, the operation of the second pump chamber 39 causes the hydraulic oil in the master cylinder M to be supplied to the first. , The air is sucked through the second suction oil passages 15a and 15b, the pressure is increased, and the pressure is supplied from the pressure increase 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 automatic brake control 1 to 4 described above, 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 in order to prohibit the automatic brake control, the cut valve 14 is normally opened, and all the inlet valves 5a to 5d are normally opened. All the outlet valves 6a to 6d are returned to the normal closed state. Accordingly, as in the case of the normal brake, 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.

Explanation of symbols

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)

In a plunger-type pump comprising a cylinder (32) and a single plunger (37) removably fitted in a cylinder bore (36) of the cylinder (32),
The cylinder (32) includes a first and second pump chambers (38, 39) whose volumes are increased and decreased by reciprocating movement of the plunger (37), and a first suction valve in the first pump chamber (38). (43) and the first suction port (41) connected via the first discharge valve (71) and the second suction valve (44) to the second pump chamber (39), respectively. ) And a second discharge port (72), and a second suction port (42) and a second discharge port (55) are provided, respectively. An input oil passage (2a, 2b) connected to the master cylinder (M), a cut valve (14) for opening and closing the input oil passage (2a, 2b), and an output oil passage (12a) connected to the wheel brakes (Ba to Bd) To 12d), the reservoirs (9a, 9b) capable of absorbing hydraulic oil, the input oil passages (2a, 2b) and the output oil passages (12a to 12d), and the output oil passages (12a to 12d) and Pressure increasing state that shuts off between reservoirs (9a, 9b), shuts off between input oil passages (2a, 2b) and output oil passages (12a-12d) and outputs oil passages (12a-12d) and reservoirs (9a, 9b) ) Brake hydraulic pressure control capable of switching between a pressure-reduced 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). 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 boost oil passage (11a, 11b) for inducing 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 brake hydraulic control device for a vehicle, 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 composed of a cylinder (32) and a single plunger (37) fitted in a cylinder bore (36) of the cylinder (32) so as to be reciprocally movable. (32) includes a first and second pump chambers (38, 39) whose volumes increase and decrease by reciprocating movement of the plunger (37), and a first suction valve (38) in the first pump chamber (38). 43) and the first suction port (41) connected through the first discharge valve (71), respectively, and the second suction valve (44) in the second pump chamber (39). And a second suction port (42) and a second discharge port (55) connected through the second discharge valve (72), respectively, and the reservoir (9a, 9b) is provided in the first suction port (41). Communication, second suction port (42) Brake hydraulic control device for a vehicle, characterized in that a suction oil passage (15a, 15b) is connected and a boost oil passage (11a, 11b) is connected to both the first and second discharge ports (54, 55). .

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