WO2021200661A1

WO2021200661A1 - Vehicular braking device

Info

Publication number: WO2021200661A1
Application number: PCT/JP2021/012879
Authority: WO
Inventors: 和俊余語
Original assignee: 株式会社アドヴィックス
Priority date: 2020-03-30
Filing date: 2021-03-26
Publication date: 2021-10-07
Also published as: JP2021160370A

Abstract

The present invention comprises a first hydraulic pressure generation unit that generates hydraulic pressure in a wheel cylinder through a first channel, and a valve unit provided in the first channel between the wheel cylinder and the first hydraulic pressure generation unit. The valve unit includes a first solenoid valve and a second solenoid valve. The first solenoid valve includes a first valving element and a first valve seat, and is a normally-open type solenoid valve, wherein the direction proceeding from the wheel cylinder to the first hydraulic pressure generation unit is the same as a first direction in which the first valving element lands on the first valve seat. The second solenoid valve is connected in parallel with the first solenoid valve, includes a second valving element and a second valve seat, and is a solenoid valve, wherein the direction proceeding from the wheel cylinder to the first hydraulic pressure generation unit is the opposite of a second direction in which the second valving element lands on the second valve seat.

Description

Vehicle braking device

The present invention relates to a vehicle braking device.

The vehicle braking device of US Pat. No. 9,205,821 includes a master cylinder unit, an electric cylinder, and an ESC actuator. A master cut valve, which is a normally open type solenoid valve, is arranged between the master cylinder unit, the electric cylinder, and the ESC actuator. In the by-wire mode, the master cut valve is closed, and the hydraulic pressure of the wheel cylinder (hereinafter, also referred to as “wheel pressure”) is adjusted by the electric cylinder or the ESC actuator.

Generally, the master cut valve includes a valve body arranged on the wheel cylinder side and a valve seat arranged on the master cylinder unit side. In this configuration, when the hydraulic pressure in the master chamber of the master cylinder unit (hereinafter also referred to as "master pressure") is higher than the wheel pressure, the direction of the force applied to the valve body due to the differential pressure is the direction in which the valve body separates from the valve seat. That is, it is in the valve opening direction. On the contrary, when the wheel pressure is higher than the master pressure, the direction of the force applied to the valve body by the differential pressure is the direction in which the valve body approaches the valve seat, that is, the valve closing direction.

U.S. Pat. No. 9,205,821

Here, the master cut valve needs to be configured so that it can be opened even if the valve is closed and the wheel pressure is higher than the master pressure (for example, even if the supply current becomes 0). be. This is because if the master cut valve cannot be opened while the wheel pressure is high, the wheel pressure cannot be reduced and the braking force cannot be reduced. In order to configure the master cut valve so that it can be opened when the master cut valve is not energized and the wheel pressure is higher than the master pressure, the spring force of the spring that urges the valve body toward the valve seat. Needs to be large.

On the other hand, if the spring force is increased, an electromagnetic force that overcomes the spring force must be generated when the valve is closed. Specifically, the electromagnetic force required for valve closing is a force larger than the sum of the force applied to the valve body by the master pressure on the valve opening side and the spring force. In order to increase the electromagnetic force required for this valve closing, it is necessary to increase the required current value and increase the size of the coil. From the viewpoint of power saving and miniaturization of the coil, in order to reduce the electromagnetic force required for valve closing, the flow path cross-sectional area of the master cut valve should be reduced, and the force and spring force that the master pressure presses against the valve body should be reduced. It is possible to make it smaller.

However, if the flow path cross-sectional area of the master cut valve is small, the resistance when the fluid passes through the master cut valve increases, which leads to a decrease in boost response when the wheel cylinder is pressurized. For example, when an ESC actuator is provided between the master cut valve and the wheel cylinder, the responsiveness of the ESC actuator when sucking fluid through the master cut valve is reduced.

An object of the present invention is to provide a vehicle braking device capable of downsizing the coil and improving the responsiveness when a hydraulic pressure generating portion such as a master cylinder unit boosts the wheel cylinder. For example, when a hydraulic pressure output unit such as an ESC actuator is provided between the valve unit and the wheel cylinder, the responsiveness when the hydraulic pressure output unit sucks the brake fluid through the valve unit can be improved. It is to provide a braking device for a vehicle.

The vehicle braking device of the present invention includes a first hydraulic pressure generating portion that generates hydraulic pressure in a wheel cylinder via a first liquid passage, and the wheel cylinder and the first hydraulic pressure generating portion in the first liquid passage. It is provided with a valve unit provided between the two. The valve unit has a first solenoid valve and a second solenoid valve. The first solenoid valve has a first valve body and a first valve seat, and the direction from the wheel cylinder toward the first hydraulic pressure generating portion is such that the first valve body is seated on the first valve seat. It is a normally open type solenoid valve that opens in the non-energized state, which is the same direction as one direction. The second solenoid valve is connected in parallel to the first solenoid valve, has a second valve body and a second valve seat, and the direction from the wheel cylinder to the first hydraulic pressure generating portion is the second valve. A solenoid valve whose body is seated in the second valve seat in the direction opposite to the second direction.

According to the present invention, when the hydraulic pressure on the wheel cylinder side of the valve unit is higher than the hydraulic pressure on the first hydraulic pressure generating portion side, the hydraulic pressure pushes the valve body of the second solenoid valve toward the valve opening side. , The valve opening is urged. When the hydraulic pressure on the first hydraulic pressure generating part side of the valve unit is higher than the hydraulic pressure on the wheel cylinder side, the hydraulic pressure pushes the valve body of the first solenoid valve toward the valve opening side, and the valve opening is promoted. .. In this way, regardless of whether the hydraulic pressure on the first hydraulic pressure generating portion side is high or low, at least one of the first solenoid valve and the second solenoid valve is in a non-energized state. As a result, the hydraulic pressure on the first hydraulic pressure generating part side and the hydraulic pressure on the wheel cylinder side of the valve unit become the same, and the other solenoid valve also opens by spring force. , Both solenoid valves open.

The hydraulic pressure generated by the first hydraulic pressure generating part can be supplied to the wheel cylinder via the open first solenoid valve. When the hydraulic pressure of the wheel cylinder is high, the hydraulic pressure of the wheel cylinder can be reduced via the second solenoid valve opened by the hydraulic pressure. Therefore, it is not necessary to design one solenoid valve in consideration of the situation where the first hydraulic pressure generating portion generates the hydraulic pressure in the wheel cylinder and the situation where the wheel pressure is reduced through the solenoid valve. Specifically, the first solenoid valve does not need to reduce the flow path area, and does not need to increase the current or increase the size of the coil. Therefore, according to the present invention, it is possible to suppress an increase in the size of the coil and improve the responsiveness of the first hydraulic pressure generating portion. Further, for example, when a hydraulic pressure output unit such as an ESC actuator is provided between the valve unit and the wheel cylinder, the responsiveness when the hydraulic pressure output unit sucks the brake fluid through the valve unit is also improved. can.

It is a block diagram of the vehicle braking device of 1st Embodiment. It is a block diagram of the actuator of 1st Embodiment. It is a conceptual diagram for demonstrating the structure of the valve unit of 1st Embodiment. It is sectional drawing which shows the structural example of the normal open type solenoid valve. It is a block diagram of the vehicle braking device of 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, parts that are the same or equal to each other are designated by the same reference numerals in the drawings. Moreover, each figure used for explanation is a conceptual diagram.

<First Embodiment>
As shown in FIG. 1, the vehicle braking device 1 of the first embodiment includes an electric cylinder (corresponding to a “second hydraulic pressure generating portion”) 2, an actuator 3, and a master cylinder unit (“first hydraulic pressure”). 4), the first liquid passage 51, the second liquid passage 52, the third liquid passage 53, the brake fluid supply passage 54, the communication control valve 61, and the first solenoid valve 62. A second solenoid valve 63, a first brake ECU 901, a second brake ECU 902, a power supply device 903, and a reservoir 45 are provided.

The first solenoid valve 62 and the second solenoid valve 63 constitute a valve unit 60. The valve unit 60 functions as a master cut valve. The function of the master cut valve is a function of hydraulically shutting off the master cylinder unit 4 and the wheel cylinder. Further, the electric cylinder 2, the master cylinder unit 4, the valve unit 60 and the like are included in the upstream unit 11. The first brake ECU 901 mainly controls the upstream unit 11. The second brake ECU 902 mainly controls the actuator 3. Note that FIG. 1 shows a non-energized state of the vehicle braking device 1.

The electric cylinder 2 is a pressurizing unit capable of supplying the first brake pressure to the

first wheel cylinders

81 and 82 and the

second wheel cylinders

83 and 84. The

first wheel cylinders

81 and 82 are wheel cylinders of the first system, and the

second wheel cylinders

83 and 84 are wheel cylinders of the second system. In the first embodiment, the first wheel cylinder 81 is provided on the right front wheel, the first wheel cylinder 82 is provided on the left rear wheel, the second wheel cylinder 83 is provided on the left front wheel, and the second wheel cylinder 84 is on the right. It is provided on the rear wheel. That is, the arrangement of the system of the first embodiment is a cross pipe (X pipe).

The electric cylinder 2 includes a cylinder 21, an electric motor 22, a piston 23, an output chamber 24, and an urging member 25. The electric motor 22 is connected to the piston 23 via a linear motion mechanism 22a that converts a rotary motion into a linear motion. The electric cylinder 2 is a single type electric cylinder in which a single output chamber 24 is formed in the cylinder 21.

The piston 23 slides in the cylinder 21 in the axial direction by driving the electric motor 22. The piston 23 is formed in a bottomed cylindrical shape that opens on one side in the axial direction and has a bottom surface on the other side in the axial direction. That is, the piston 23 includes a cylindrical portion that forms an opening and a cylindrical portion that forms a bottom surface (pressure receiving surface).

The output chamber 24 is partitioned by the cylinder 21 and the piston 23, and the volume changes due to the movement of the piston 23. The output chamber 24 is connected to the reservoir 45 and the actuator 3. The piston 23 slides in a sliding region composed of a communication region for communicating between the output chamber 24 and the reservoir 45 and a blocking region for blocking between the output chamber 24 and the reservoir 45. The communication area includes the initial position of the piston 23 that maximizes the volume of the output chamber 24. The blocking region is larger than the communication region in the axial direction. The urging member 25 is a spring that is arranged in the output chamber 24 and urges the piston 23 to the other side in the axial direction (toward the initial position). When the electric cylinder 2 is de-energized, the electric motor 22 is stopped, and the urging member 25 returns the piston 23 to the initial position.

The actuator 3 has a first hydraulic pressure output unit (corresponding to a “hydraulic pressure output unit”) 31 capable of adjusting the pressure of the

first wheel cylinders

81 and 82 and a second liquid capable of adjusting the pressure of the

second wheel cylinders

83 and 84. It is a pressure adjusting unit having a pressure output unit 32. The first hydraulic pressure output unit 31 generates the

first wheel cylinders

81 and 82 by generating a differential pressure between the hydraulic pressure input from the first liquid passage 51 and the hydraulic pressure of the

first wheel cylinders

81 and 82. It is configured to pressurize. The second hydraulic pressure output unit 32 generates a differential pressure between the hydraulic pressure input from the second hydraulic passage 52 and the hydraulic pressure of the

second wheel cylinders

83 and 84 to generate the

second wheel cylinders

83 and 84. It is configured to pressurize.

The actuator 3 is a so-called ESC actuator, and can independently regulate the hydraulic pressure of each wheel cylinder 81 to 84. The actuator 3 executes, for example, anti-skid control (also referred to as ABS control), electronic stability control (ESC), traction control, or the like according to the control of the second brake ECU 902. The first hydraulic pressure output unit 31 and the second hydraulic pressure output unit 32 are independent of each other on the hydraulic pressure circuit of the actuator 3. The configuration of the actuator 3 will be described later.

The master cylinder unit 4 is a pressurizing unit capable of supplying master pressure to the first hydraulic pressure output unit 31 via the first liquid passage 51. More specifically, the master cylinder unit 4 is connected to the reservoir 45 and mechanically supplies the fluid to the first hydraulic pressure output unit 31 of the actuator 3 according to the operating amount (stroke and / or pedaling force) of the brake operating member Z. It is a unit to do. The master cylinder unit 4 is configured to be able to pressurize the

first wheel cylinders

81 and 82 via the first hydraulic pressure output unit 31. The master cylinder unit 4 includes a master cylinder 41 and a master piston 42.

The master cylinder 41 is a bottomed cylindrical member and includes an input port 411 and an output port 412. The master piston 42 is a piston member that slides in the master cylinder 41 according to the amount of operation of the brake operating member Z. The master piston 42 is formed in a bottomed cylindrical shape that opens on one side in the axial direction and has a bottom surface on the other side in the axial direction.

In the master cylinder 41, a single master chamber 41a is formed by the master piston 42. The volume of the master chamber 41a fluctuates due to the movement of the master piston 42. When the master piston 42 moves to one side in the axial direction, the volume of the master chamber 41a decreases, and the hydraulic pressure of the master chamber 41a, that is, the master pressure increases. The master chamber 41a is provided with an urging member 41b that urges the master piston 42 toward the initial position (on the other side in the axial direction). When the brake operation is released, the urging member 41b returns the master piston 42 to the initial position.

The output port 412 communicates the master chamber 41a with the first liquid passage 51. The input port 411 communicates the master chamber 41a with the reservoir 45 via a through hole 421 formed in the cylindrical portion of the master piston 42. At the initial position of the master piston 42, which maximizes the volume of the master chamber 41a, the input port 411 and the through hole 421 overlap, and the master chamber 41a and the reservoir 45 communicate with each other. When the master piston 42 moves from the initial position to one side in the axial direction by a predetermined amount (overlap distance), the connection between the master chamber 41a and the reservoir 45 is cut off.

A stroke simulator 43 and a simulator cut valve 44 are connected to the master cylinder unit 4. The stroke simulator 43 is a device that generates a reaction force (load) with respect to the operation of the brake operating member Z. The stroke simulator 43 is composed of, for example, a cylinder, a piston, and an urging member. The stroke simulator 43 and the output port 412 of the master cylinder 41 are connected by a liquid passage 43a. The simulator cut valve 44 is a solenoid valve provided in the liquid passage 43a.

(Liquid passage and solenoid valve)
The first liquid passage 51 connects the master cylinder unit 4 and the first hydraulic pressure output unit 31 of the actuator 3. The second liquid passage 52 connects the electric cylinder 2 and the second hydraulic pressure output unit 32. The third liquid passage 53 connects the first liquid passage 51 and the second liquid passage 52.

The valve unit 60 is provided in the first liquid passage 51. The master cylinder unit 4 is configured to be able to supply fluid via the first liquid passage 51 and the valve unit 60. The first hydraulic pressure output unit 31 is configured to suck fluid from the first liquid passage 51 when pressurizing the

first wheel cylinders

81 and 82.

The communication control valve 61 is a normally closed type solenoid valve provided in the third liquid passage 53. The communication control valve 61 permits or prohibits the supply of fluid to the first hydraulic pressure output unit 31 by the electric cylinder 2. The communication control valve 61 has a valve body on the

first wheel cylinder

81, 82 side (first system side) of the valve seat in order to prevent backflow of fluid from the

first wheel cylinders

81, 82 to the electric cylinder 2 when the valve is closed. ) Is placed. As a result, even if the hydraulic pressure of the

first wheel cylinders

81 and 82 becomes higher than the output pressure of the electric cylinder 2 when the communication control valve 61 is closed, a force is applied to the valve body in the direction of being pressed against the valve seat ( Self-sealing) and keeps the valve closed.

The brake fluid supply path 54 connects the reservoir 45 and the input port 211 of the electric cylinder 2. The reservoir 45 stores fluid, and the internal pressure is maintained at atmospheric pressure. Further, the inside of the reservoir 45 is divided into two

rooms

451 and 452 in which fluid is stored. A master cylinder unit 4 is connected to one room 451 of the reservoir 45, and an electric cylinder 2 is connected to the other room 452 via a brake fluid supply path 54. The reservoir 45 may consist of two separate reservoirs instead of the two chambers.

(Example of actuator configuration)
A configuration example of the actuator 3 will be briefly described by taking a liquid passage connected to the first wheel cylinder 81 as an example. As shown in FIG. 2, the first hydraulic pressure output unit 31 of the actuator 3 includes a liquid passage 311, a differential pressure control valve 312, a holding valve 313, a pressure reducing valve 314, a pump 315, an electric motor 316, and the like. It includes a reservoir 317, a perfusion fluid passage 317a, and a pressure sensor 75.

The liquid passage 311 connects the first liquid passage 51 and the first wheel cylinder 81. A pressure sensor 75 is provided in the liquid passage 311. The differential pressure control valve 312 is a normally open type linear solenoid valve for generating a differential pressure between upstream and downstream. A check valve 312a that allows only the flow of brake fluid from the first liquid passage 51 to the first wheel cylinder 81 is provided in parallel with the differential pressure control valve 312.

The holding valve 313 is a normally open type solenoid valve provided between the differential pressure control valve 312 and the first wheel cylinder 81 in the liquid passage 311. Further, a check valve 313a is provided in parallel with the holding valve 313. The pressure reducing valve 314 is a normally closed type solenoid valve provided in the pressure reducing liquid passage 314a. The decompression liquid passage 314a connects the portion of the liquid passage 311 between the holding valve 313 and the first wheel cylinder 81 and the reservoir 317.

The pump 315 is operated by the driving force of the electric motor 316. The pump 315 is provided in the pump liquid passage 315a. The pump liquid passage 315a connects a portion of the liquid passage 311 between the differential pressure control valve 312 and the holding valve 313 (hereinafter referred to as “branch portion X”) and the reservoir 317. When the pump 315 is activated, the fluid is discharged from the reservoir 317 to the branch X.

Reservoir 317 is a pressure regulating reservoir. The reflux liquid passage 317a connects the first liquid passage 51 and the reservoir 317. The brake fluid in the reservoir 317 is preferentially sucked into the reservoir 317 by the operation of the pump 315, and when the brake fluid in the reservoir 317 decreases, the valve is opened and the brake is applied from the first fluid passage 51 via the reflux fluid passage 317a. The liquid is configured to be inhaled.

When the first wheel cylinder 81 is pressurized by the actuator 3, the second brake ECU 902 responds to the target differential pressure (hydraulic pressure of the first wheel cylinder 81> hydraulic pressure of the first liquid passage 51) in the differential pressure control valve 312. A control current is applied to close the differential pressure control valve 312. At this time, the holding valve 313 is open and the pressure reducing valve 314 is closed. Further, when the pump 315 is operated, the fluid is supplied from the first liquid passage 51 and the reservoir 317 to the branch portion X. As a result, the first wheel cylinder 81 is pressurized.

When the difference between the hydraulic pressure of the first wheel cylinder 81 (hereinafter, also referred to as “wheel pressure”) and the hydraulic pressure of the first liquid passage 51 is about to exceed the target differential pressure, the differential pressure control valve is affected by the magnitude of the force. 312 opens the valve. The wheel pressure after pressurization is determined by the hydraulic pressure of the first liquid passage 51, that is, the basal hydraulic pressure, and the target differential pressure. In this way, the actuator 3 pressurizes the wheel cylinders 81 to 84 by generating a differential pressure between the basic hydraulic pressure, which is the output pressure of the electric cylinder 2, and the wheel pressure.

When the wheel pressure is reduced by the actuator 3 by the actuator 3 by anti-skid control or the like, the second brake ECU 902 operates the pump 315 with the pressure reducing valve 314 opened and the holding valve 313 closed to operate the pump 315 in the wheel cylinder 81. Pump back the brake fluid. When the wheel pressure is held by the actuator 3, the second brake ECU 902 closes the holding valve 313 and the pressure reducing valve 314. When the wheel pressure is pressurized or reduced only by the operation of the electric cylinder 2 or the master cylinder unit 4, the second brake ECU 902 opens the differential pressure control valve 312 and the holding valve 313, and closes the pressure reducing valve 314.

As described above, the vehicle braking device 1 of the first embodiment includes a master cylinder unit 4 that generates hydraulic pressure in the first wheel cylinder via the first liquid passage 51 and a first wheel cylinder in the first liquid passage 51. It is provided with a valve unit 60 provided between the master cylinder unit 4 and the master cylinder unit 4. Further, the vehicle braking device 1 is provided between the valve unit 60 and the

first wheel cylinders

81 and 82 in the first liquid passage 51, and sucks fluid from the master cylinder unit 4 via the valve unit 60 to suck the liquid. A first hydraulic pressure output unit 31 that outputs pressure is provided.

(Brake ECU and various sensors)
The first brake ECU 901 and the second brake ECU 902 (hereinafter, also referred to as "

brake ECUs

901 and 902") are electronic control units including a CPU and a memory, respectively. Each

brake ECU

901, 902 includes one or more processors that perform various controls. The first brake ECU 901 and the second brake ECU 902 are separate ECUs, and are connected to each other so that information (control information, etc.) can be communicated with each other.

The first brake ECU 901 is controllably connected to the electric cylinder 2 and the

solenoid valves

61, 62, 63, 44, respectively. The second brake ECU 902 is controllably connected to the actuator 3. The

brake ECUs

901 and 902 execute various controls based on the detection results of the various sensors. As various sensors, the vehicle braking device 1 is provided with, for example, a stroke sensor 71,

pressure sensors

72, 73, 75, a wheel speed sensor (not shown), an acceleration sensor (not shown), and the like.

The stroke sensor 71 detects the stroke of the brake operating member Z. The vehicle braking device 1 is provided with two stroke sensors 71 so as to have a one-to-one correspondence with the

brake ECUs

901 and 902. The

brake ECUs

901 and 902 acquire stroke information from the corresponding stroke sensors 71, respectively. The pressure sensor 72 is a sensor that detects the master pressure, and is provided in, for example, the first liquid passage 51. The pressure sensor 73 is a sensor that detects the output pressure (first brake pressure) of the electric cylinder 2, and is provided in, for example, the second liquid passage 52. The pressure sensor 75 detects the input hydraulic pressure from the first liquid passage 51 to the first hydraulic pressure output unit 31. The detected values of the various sensors may be transmitted to both

brake ECUs

901 and 902.

The first brake ECU 901 receives the detection results of the stroke sensor 71 and the

pressure sensors

72 and 73, and controls the electric cylinder 2 and the

solenoid valves

61, 62, 63 and 44 based on the detection results. The first brake ECU 901 can calculate each wheel pressure based on the detection results of the

pressure sensors

72 and 73 and the control state of the actuator 3.

The second brake ECU 902 receives the detection results of the stroke sensor 71 and the pressure sensor 75, and controls the actuator 3 based on the detection results. The

brake ECUs

901 and 902 can calculate each wheel pressure based on the control state of the pressure sensor 75 and the actuator 3. The second brake ECU 902 sets a target value of the differential pressure between the input pressure and the hydraulic pressures of the

first wheel cylinders

81 and 82, and a target value of the differential pressure between the input pressure and the hydraulic pressures of the

second wheel cylinders

83 and 84. do.

The power supply device 903 is a device that supplies electric power to the

brake ECUs

901 and 902. The power supply unit 903 includes a battery. The power supply device 903 is connected to both

brake ECUs

901 and 902. That is, in the first embodiment, power is supplied from the power supply device 903 common to the two

brake ECUs

901 and 902.

(Normal control)
The first brake ECU 901 executes normal control depending on the situation. In normal control, the communication control valve 61 and the simulator cut valve 44 are opened, the first solenoid valve 62 and the second solenoid valve 63 are closed, and the electric cylinder 2 is used to open the

first wheel cylinders

81, 82 and the second wheel. This is a control (control mode) for adjusting the hydraulic pressure of the

cylinders

83 and 84.

In normal control, the communication control valve 61 is opened and the valve unit 60 is closed, and at least one of the electric cylinder 2 and the actuator 3 is used to apply the hydraulic pressure of the

first wheel cylinders

81 and 82 and the

second wheel cylinders

83 and 84. It is a control (control mode) to be adjusted. In normal control, the simulator cut valve 44 is opened.

In normal control, the master cylinder unit 4 and the wheel cylinders 81 to 84 are hydraulically separated to form a so-called by-wire mode in which the wheel pressure is adjusted by controlling the

brake ECUs

901 and 902. Specifically, the first brake ECU 901 is based on the data detected by the stroke sensor 71 and the pressure sensor 72 in a state where the valve unit 60 is closed and the simulator cut valve 44 and the communication control valve 61 are opened. Drive the electric cylinder 2. The first brake ECU 901 sets a target deceleration and a target wheel pressure based on the detection results of the stroke sensor 71 and the pressure sensor 72, and controls the electric cylinder 2 so that the actual wheel pressure approaches the target wheel pressure. The second brake ECU 902 operates the actuator 3 when executing anti-skid control or the like.

(Details of valve unit)
The valve unit 60 of the present embodiment is provided in the first liquid passage 51, and includes a normally open type first solenoid valve 62 and a second solenoid valve 63, respectively. A normally open type solenoid valve is a solenoid valve that opens in a non-energized state. As shown in FIG. 3, the first solenoid valve 62 includes a first valve body 621 arranged on the

first wheel cylinder

81, 82 side, a first valve seat 622 arranged on the reservoir 45 side, and a first penetration. It has a hole 623 and. The first through hole 623 is formed in the first valve seat 622 so that fluid can be circulated by opening the first solenoid valve 62. The first solenoid valve 62 is closed when the first valve body 621 abuts on the first valve seat 622 and closes the first through hole 623. In addition, in FIG. 3 and FIG. 5, in order to display the valve body and the valve seat, the solenoid valve constituting the valve unit is represented by a conceptual diagram.

The second solenoid valve 63 includes a second solenoid valve 631 arranged in parallel with the first solenoid valve 62 and arranged on the reservoir 45 side, and a second valve seat 632 arranged on the

first wheel cylinders

81 and 82 sides. , And a second through hole 633. The first liquid passage 51 is branched into a liquid passage 511 in which the first solenoid valve 62 is arranged and a liquid passage 512 in which the second solenoid valve 63 is arranged. The second through hole 633 is formed in the second valve seat 632 so that fluid can be circulated by opening the second solenoid valve 63. The second solenoid valve 63 is closed when the second valve body 631 comes into contact with the second valve seat 632 and closes the second through hole 633.

As described above, the first solenoid valve 62 has the first valve body 621 and the first valve seat 622, and the first valve body 621 is the first valve in the direction from the

first wheel cylinders

81 and 82 toward the reservoir 45. It is configured to be in the same direction as the first direction in which the seat 622 is seated. The second solenoid valve 63 is a solenoid valve connected in parallel to the first solenoid valve 62, has a second valve body 631 and a second valve seat 632, and is connected to the reservoir 45 from the

first wheel cylinders

81 and 82. The direction in which the second valve body 631 is seated is opposite to the second direction in which the second valve body 631 is seated on the second valve seat 632.

Here, the configuration of the normally open type solenoid valve 600 will be briefly described. As shown in FIG. 4, the solenoid valve 600 includes a valve body 601, a valve seat 602, a through hole 603, a plunger 604, an urging member 605, and a coil 606. The valve body 601 is arranged so as to face the valve seat 602. The valve seat 602 is formed with a through hole 603 that connects the valve body chamber 607 and the external flow path C1. The valve body chamber 607 accommodates the valve body 601 and the urging member 605 and communicates with the external flow path C2. The solenoid valve 600 is closed when the valve body 601 is seated (contacted) with the valve seat 602 and closes the through hole 603, and the valve body 601 moves so that the through hole 603 and the valve body chamber 607 communicate with each other. It opens the valve. In this case, the flow path of the solenoid valve 600 is formed by the through hole 603 and the valve body chamber 607.

The valve body 601 is provided at the tip of the plunger 604. The valve body 601 and the plunger 604 are urged by the urging member (spring) 605 in a direction away from the valve seat 602. A coil 606 is arranged on the outer peripheral side of the plunger 604. When a current (control current) is supplied to the coil 606, an electromagnetic force is generated in the direction in which the valve body 601 approaches the valve seat 602.

In the valve open state, the solenoid valve 600 communicates one external flow path C1 with the other external flow path C2 via the through hole 603 and the valve body chamber 607. In the solenoid valve 600, the valve body 601 is opened apart from the valve seat 602 by the urging member 605 in the non-energized state, and the valve body 601 is opened by the electromagnetic force in the state where the control current equal to or higher than the predetermined current value is supplied. It abuts on 602 and closes the valve.

The hydraulic pressure of the valve body chamber 607 is the same as the hydraulic pressure of the external flow path C2, and the hydraulic pressure on the back side of the plunger 604 is also the same as the hydraulic pressure of the external flow path C2. That is, the hydraulic pressure of the external flow path C2 presses the valve body 601 in the direction of approaching the valve seat 602. On the other hand, the hydraulic pressure of the external flow path C1 presses the valve body 601 in the direction away from the valve seat 602 through the through hole 603. This pressing force increases as the cross-sectional area of the flow path of the through hole 603 increases. The flow path cross-sectional area is the area of the cross section obtained by cutting the flow path in a plane orthogonal to the extension direction (fluid flow direction) of the flow path. More specifically, the pressing force in the direction of separating the valve body 601 from the valve seat 602 increases not according to the cross-sectional area of the flow path but according to the projected area of the valve body 601 in contact with the valve seat 602. This can be said to be the seal area when the valve body 601 is seated on the valve seat 602. In the present specification, for the sake of clarity, the pressing force will be described as changing according to the cross-sectional area.

When the hydraulic pressure of the external flow path C1 is higher than the hydraulic pressure of the external flow path C2, the valve body 601 receives a force on the valve opening side due to the differential pressure. On the contrary, when the hydraulic pressure of the external flow path C2 is higher than the hydraulic pressure of the external flow path C1, the valve body 601 receives a force on the valve closing side due to the differential pressure. Hereinafter, the direction from the valve body 601 to the valve seat 602 is also referred to as a sealing direction. The sealing direction can also be said to be the self-sealing direction.

Explaining the correspondence between FIGS. 3 and 4, the valve body 601 corresponds to the first valve body 621 and the second valve body 631, and the valve seat 602 corresponds to the first valve seat 622 and the second valve seat 632. The through hole 603 corresponds to the first through hole 623 and the second through hole 633.

In the first solenoid valve 62, the hydraulic pressure of the external flow path C1 corresponds to the master pressure, and the hydraulic pressure of the external flow path C2 is in a state where the communication control valve 61 is open and the electric cylinder 2 is generating the hydraulic pressure. Corresponds to the output hydraulic pressure of the electric cylinder 2. In the second solenoid valve 63, when the communication control valve 61 is open and the electric cylinder 2 is generating the hydraulic pressure, the hydraulic pressure of the external flow path C1 corresponds to the output hydraulic pressure of the electric cylinder 2 and is an external flow. The hydraulic pressure of the path C2 corresponds to the master pressure. As described above, in the first liquid passage 51, the sealing direction of the first solenoid valve 62 (first direction) and the sealing direction of the second solenoid valve 63 (second direction) are opposite to each other.

(Example of valve unit configuration)
In the valve unit 60 of the first embodiment, the flow path cross-sectional area of the first through hole 623 is larger than the flow path cross-sectional area of the second through hole 633. As a result, when the first solenoid valve 62 is opened, the fluid can easily flow through the first solenoid valve 62.

Further, the first differential pressure at which the first solenoid valve 62 can maintain the closed state by the current supply is smaller than the second differential pressure at which the second solenoid valve 63 can maintain the closed state by the current supply. The first differential pressure is the differential pressure between the

first wheel cylinders

81 and 82 and the master pressure when the master pressure is higher than the hydraulic pressure of the

first wheel cylinders

81 and 82.

Here, an example will be described in which a vehicle braking device 1 is provided in a vehicle provided with a regenerative braking device capable of applying a regenerative braking force. When the brake operating member Z is operated with the first solenoid valve 62 and the second solenoid valve 63 closed and the brake is braked only by the regenerative braking force, the master pressure becomes larger than 0, but the wheel pressure becomes higher. It remains 0. In such a situation, the master pressure will be higher than the wheel pressure. Therefore, the first differential pressure (difference pressure that can maintain the closed valve) of the first solenoid valve 62 is set to a value (for example, 5 MPa) corresponding to the maximum value of the master pressure assumed by the driver's depression of the brake operating member Z. It suffices if it is done.

The second differential pressure is the differential pressure between the hydraulic pressure of the

first wheel cylinders

81 and 82 and the master pressure when the hydraulic pressure of the

first wheel cylinders

81 and 82 is higher than the master pressure. The situation where the wheel pressure becomes larger than the master pressure is, for example, the situation where the wheel pressure is pressurized in the by-wire mode (normal control), the situation where the wheel pressure is pressurized without the driver's braking operation such as automatic brake control, etc. Can be mentioned. Therefore, the second solenoid valve 63 (the differential pressure that can maintain the closed valve) is the second solenoid valve 63 in a state where the master pressure is 0 and the pressure is maximized by using the electric cylinder 2 and the actuator 3. May be set to a value that does not open the valve (for example, 20 MPa).
As described above, the vehicle braking device 1 is configured to be able to generate a hydraulic pressure higher than the hydraulic pressure that can be generated by the master cylinder unit 4 in the

first wheel cylinders

81 and 82, and the valve unit 60 in the first liquid passage 51. An electric cylinder 2 connected to the portion between the

first wheel cylinders

81 and 82 via a second liquid passage 52 is provided. The second differential pressure at which the second solenoid valve 63 can maintain the closed state by the current supply is larger than the first differential pressure at which the first solenoid valve 62 can maintain the closed state by the current supply, and is electrically operated. The value is equal to or higher than the hydraulic pressure that the cylinder 2 can generate.

(Effect of the first embodiment)
According to the first embodiment, when the first solenoid valve 62 and the second solenoid valve 63 are opened, the hydraulic pressure on the

first wheel cylinders

81 and 82 side of the valve unit 60 is higher than the hydraulic pressure on the master cylinder 41 side. If it is too high, the hydraulic pressure pushes the second valve body 631 of the second solenoid valve 63 toward the valve opening side, and the valve opening is promoted. On the other hand, when the hydraulic pressure on the master cylinder 41 side of the valve unit 60 is higher than the hydraulic pressure on the

first wheel cylinders

81 and 82, the hydraulic pressure causes the first valve body 621 of the first solenoid valve 62 to open. It is pressed to the side and the valve opening is promoted. As described above, when opening the valve unit 60, even if the hydraulic pressure on either side of the valve unit 60 is relatively high, the operation of one of the solenoid valves is promoted to the valve opening side.

As a result, the second solenoid valve 63 is opened when the wheel pressure is higher than the master pressure without increasing the spring force of the first solenoid valve 62. That is, even if the flow path cross-sectional area of the first solenoid valve 62 is increased, the spring force can be reduced, so that an increase in the electromagnetic force required for closing the valve can be suppressed. That is, according to the first embodiment, it is possible to achieve both miniaturization of the coil (606) and an increase in the cross-sectional area of the flow path.

For example, when an electric failure occurs in the first brake ECU 901, the electric cylinder 2, the valve unit 60, the communication control valve 61, and the simulator cut valve 44 are in a non-energized state. Therefore, the electric cylinder 2 is stopped, the valve unit 60 is opened, and the communication control valve 61 and the simulator cut valve 44 are closed. In this case, the second brake ECU 902 controls the actuator 3 to pressurize the wheel cylinders 81 to 84. That is, the first hydraulic pressure output unit 31 sucks the fluid from the master cylinder unit 4 via the valve unit 60.

Here, according to the first embodiment, as in the above configuration example, the flow path cross-sectional area of the first through hole 623 of the first solenoid valve 62 can be increased, so that the boost response of the wheel cylinder by the master pressure can be increased. Improves sex. Further, the fluid suction by the actuator 3 through the valve unit 60 becomes smooth. Therefore, the pressurization by the first hydraulic pressure output unit 31 becomes smooth, and the responsiveness of the first hydraulic pressure output unit 31 is improved. As described above, according to the first embodiment, it is possible to reduce the size of the coil and improve the responsiveness of pressurization by the master cylinder unit 4.

Further, when one of the first solenoid valve 62 and the second solenoid valve 63 is opened in the non-energized state, the differential pressure between the input and output of the valve unit 60 becomes 0, and the first solenoid valve 62 and the second solenoid valve become zero. The other of 63 is also opened. That is, according to the first embodiment, the first solenoid valve 62 and the second solenoid valve 63 may be configured to be opened when the differential pressure is 0, and the first solenoid valve 62 and the second solenoid valve 63 are attached. The spring force of the force member (605) can be reduced.

<Second Embodiment>
As shown in FIG. 5, the master cylinder unit 40 of the second embodiment is a tandem type master cylinder unit having two master chambers 410a and 410b. The master cylinder unit 40 includes a master cylinder 410, a first master piston 401, a second master piston 402, and urging

members

403 and 404.

The master cylinder 410 internally includes a first master chamber 410a partitioned by the first master piston 401, and a second master chamber 410b partitioned by the first master piston 401 and the second master piston 402. .. The urging member 403 is arranged in the first master chamber 410a and urges the first master piston 401 toward the initial position. The urging member 404 is arranged in the second master chamber 410b and urges the second master piston 402 toward the initial position.

The master cylinder unit 40 is configured such that the first master chamber 410a and the second master chamber 410b have the same pressure. The communication between the reservoir 45 and the master chambers 410a and 410b is cut off when the

master pistons

401 and 402 advance by a predetermined amount from the initial position. The first master chamber 410a is connected to the first liquid passage 51. The communication control valve 61 is a normally closed solenoid valve having the same purpose and function as the communication control valve 61 of the first embodiment. The communication control valve 61 is provided in the third liquid passage 53, and permits / prohibits the supply of fluid from the electric cylinder 2 to the first hydraulic pressure output unit 31.

The first master chamber 410a is connected to the first hydraulic pressure output unit 31 via the first liquid passage 51. The second master chamber 410b is connected to the second hydraulic pressure output unit 32 via the liquid passage 55, the valve unit 60b, and the second liquid passage 52. The liquid passage 55 connects the second master chamber 410b and the second liquid passage 52. The second hydraulic pressure output unit 32 is configured to suck in fluid from the liquid passage 55 and the second liquid passage 52 when pressurizing the

second wheel cylinders

83 and 84.

As described above, the vehicle braking device 10 of the second embodiment includes two

valve units

60 and 60b. One valve unit 60 is provided in the first liquid passage 51 as in the first embodiment, and includes the first solenoid valve 62 and the second solenoid valve 63. The other valve unit 60b is provided in the liquid passage 55 and includes a first solenoid valve 62b and a second solenoid valve 63b.

The first solenoid valve 62b and the second solenoid valve 63b are normally open type solenoid valves. The first solenoid valve 62b has a first valve body 621b arranged on the

second wheel cylinders

83 and 84 sides and a first valve seat 622b arranged on the master cylinder 410 side. That is, the sealing direction (first direction) of the first solenoid valve 62b is the same as the direction from the

second wheel cylinders

83 and 84 toward the master cylinder unit 40.

The second solenoid valve 63b is arranged in parallel with the first solenoid valve 62b. The second solenoid valve 63b has a second valve body 631b arranged on the master cylinder 410 side and a second valve seat 632b arranged on the

second wheel cylinders

83 and 84 side. The sealing direction (second direction) of the second solenoid valve 63b is opposite to the direction from the

second wheel cylinders

83 and 84 toward the master cylinder unit 40. As described above, in the valve unit 60b as well, the sealing direction of the first solenoid valve 62b and the sealing direction of the second solenoid valve 63b are opposite to each other, as in the valve unit 60.

Depending on the configuration of the second embodiment, the valve unit 60 and the valve unit 60b exert the same effect as that of the first embodiment. The reservoir 45 is divided into three rooms, the room 451 is connected to the second master room 410b, the room 452 is connected to the electric cylinder 2, and the room 453 is connected to the first master room 410a.

<Others>
The present invention is not limited to the above embodiment. The present invention can also be applied to, for example, a vehicle including a regenerative braking device (hybrid vehicle or electric vehicle), a vehicle that executes automatic braking control, or an autonomous driving vehicle. Further, the system may be arranged in front and rear piping such that the wheel cylinder of the first system is provided on the front wheels and the wheel cylinder of the second system is provided on the rear wheels. The first solenoid valve 62 and the second solenoid valve 63 may be normally closed type solenoid valves. Further, instead of the master cylinder unit 4, a pressurizing unit capable of generating hydraulic pressure according to the driving of the motor may be provided. Further, the present invention can be applied even when the electric cylinder 2 is not collapsed. The present invention is also applied to a case where a vehicle braking device configured to operate either the electric cylinder 2 or the actuator 3 according to a required braking force operates the actuator 3 without operating the electric cylinder 2. Can be used.

The generating part corresponding to the first hydraulic pressure generating part may be other than the

master cylinder units

4 and 40. For example, the generating portion corresponding to the first hydraulic pressure generating portion may be an electric cylinder. Further, instead of the

master cylinder units

4 and 40, a plurality of generating units may be provided. For example, it may be composed of a plurality of electric cylinders. A plurality of electric cylinders may be arranged in parallel. In this case, one solenoid valve may be provided in each of the plurality of liquid passages connecting the plurality of electric cylinders and the wheel cylinders. In this case, the valve unit is composed of a plurality of solenoid valves provided in the plurality of liquid passages.

The second solenoid valve 63 may be a normally closed solenoid valve that closes in a non-energized state. Hereinafter, a case where the second solenoid valve 63 is a normally closed type solenoid valve will be described. For example, when the first withstand voltage is larger than the second withstand voltage due to the relationship between the first spring force of the first solenoid valve 62 and the first seal area, both solenoid valves are de-energized so that the wheel pressure becomes the first withstand voltage. If it is smaller than, the first solenoid valve 62 opens, so that the wheel pressure can be reduced. The first withstand voltage is a differential pressure (hydraulic pressure on the wheel cylinder side> hydraulic pressure on the master cylinder 41 side) in which the first solenoid valve 62 in the non-energized state can maintain the valve opening. The second withstand voltage is a differential pressure (hydraulic pressure on the wheel cylinder side> hydraulic pressure on the master cylinder 41 side) in which the second solenoid valve 63 in the non-energized state can maintain the closed valve. In this case, the second solenoid valve 63 may be provided with an urging member that urges the valve body in the valve closing direction, and may be configured so that a force acts on the valve body in the valve closing direction when energized. That is, the second solenoid valve 63 acts on the side where both the urging force and the solenoid force are closed. In this case, the total of the urging force by the urging member and the force acting in the valve closing direction when energized may be larger than the pressure output by the electric cylinder 2. As a result, it is possible to prevent the fluid output by the electric cylinder 2 from flowing toward the master cylinder unit 4. Since the spring force of the second solenoid valve 63 may be small, the second withstand voltage can be reduced, and the first withstand voltage of the first solenoid valve 62 can also be reduced. Therefore, the flow path area of the first solenoid valve 62 can be increased and the spring force of the first solenoid valve 62 can be reduced, so that it is not necessary to increase the size of the coil. As described above, even if the second solenoid valve 63 is a normally closed type solenoid valve, the flow path area of the first solenoid valve 62 can be increased, so that the boost responsiveness when pressurized by the master cylinder unit 4 can be improved. Can be improved. When an actuator 3 for sucking fluid from the master cylinder unit 4 is provided between the master cylinder unit 4 and the wheel cylinder, the suction responsiveness of the actuator 3 can be improved. When the wheel pressure is high, the differential pressure exceeds the second withstand voltage by de-energizing the second solenoid valve 63, the second solenoid valve 63 opens, and the wheel pressure can be reduced. .. The second solenoid valve 63 can also be applied to the second embodiment.

Claims

A first hydraulic pressure generating part that generates hydraulic pressure in the wheel cylinder via the first liquid passage,
A valve unit provided between the wheel cylinder and the first hydraulic pressure generating portion in the first liquid passage is provided.
The valve unit
It has a first valve body and a first valve seat, and the direction from the wheel cylinder toward the first hydraulic pressure generating portion is the same as the first direction in which the first valve body is seated on the first valve seat. A normally open type first solenoid valve that opens in a certain non-energized state,
It is connected in parallel to the first solenoid valve, has a second valve body and a second valve seat, and the second valve body is the second valve in the direction from the wheel cylinder to the first hydraulic pressure generating portion. The second solenoid valve, which is in the opposite direction to the second direction in which the seat is seated,
A braking device for vehicles.
The vehicle braking device according to claim 1, wherein the second solenoid valve is a normally open type solenoid valve that opens in a non-energized state.
The flow path cross-sectional area of the first through hole formed in the first valve seat so that the fluid flows in the opened state is formed in the second valve seat so that the fluid flows in the opened state. The vehicle braking device according to claim 1 or 2, which is larger than the flow path cross-sectional area of the second through hole.
Further, a hydraulic pressure output unit provided between the valve unit and the wheel cylinder in the first liquid passage, sucks fluid from the first hydraulic pressure generating unit via the valve unit, and outputs the hydraulic pressure. The vehicle braking device according to claim 3, which is provided.
A hydraulic pressure larger than the hydraulic pressure that can be generated by the first hydraulic pressure generating portion is configured to be able to be generated in the wheel cylinder, and a second liquid pressure is formed in a portion between the valve unit and the wheel cylinder in the first liquid passage. Further provided with a second hydraulic pressure generator connected via a liquid passage,
The second differential pressure at which the second solenoid valve can be maintained in the closed state by the current supply is larger than the first differential pressure at which the first solenoid valve can be maintained in the closed state by the current supply.
The vehicle braking device according to any one of claims 1 to 4, wherein the second differential pressure is a value equal to or higher than a hydraulic pressure that can be generated by the second hydraulic pressure generating portion.