JP2003312467A - Brake fluid pressure controller for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To preclude a position of a braking operation member from being varied in automatic braking, and to preclude a relation between an operation input and a stroke from being varied even when the braking operation member is operated during execution of the automatic braking, so as to enhance braking operation feeling, in a vehicular brake fluid pressure controller for operating a master cylinder by booster hydraulic pressure provided by governing hydraulic pressure from a hydraulic pressure supplying source. <P>SOLUTION: A pressure governing valve cylinder 31A is engaged slidably with the second cylinder body 30 in a rear side of a master piston 9, an input transmission mechanism 4A having simulator springs 64, 65 is provided between a sliding member 32 engaged slidably with the valve cylinder 31A and a brake operation member 1, the hydraulic pressure supplying source 2 is connected to a booster hydraulic chamber 28 via the first opening and closing valve 75, and a reservoir R is connected to a release port 53 via the second opening and closing valve 76. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle brake fluid pressure control device, and more particularly to a sliding member slidably fitted to a pressure regulating valve cylinder having an input port, a release port and an output port. The reaction force based on the output hydraulic pressure of the output port and the brake operation force input from the brake operation member via the input transmission mechanism are applied, and the sliding member moves back and forth so that the reaction force and the brake operation force are balanced. As a result, the hydraulic pressure from the hydraulic pressure supply source is regulated and output from the output port, and the boosted hydraulic pressure is used to operate the master cylinder so that the boosted brake hydraulic pressure acts on the wheel brakes. The present invention relates to a vehicle brake fluid pressure control device.

[0002]

2. Description of the Related Art Conventionally, such a brake fluid pressure control device is
For example, it is already known from Japanese Patent Laid-Open No. 2000-219125.

[0003]

In such a brake fluid pressure control device, in order to achieve automatic braking in which the brake fluid pressure is applied to the wheel brakes when the brake operating member is not braked, the above brake fluid pressure control device is used. In the pressure control device, a normally closed solenoid valve is provided between the hydraulic pressure supply source and the boost hydraulic chamber, and a normally open solenoid valve is provided between the boost hydraulic chamber and the reservoir.

However, in the above-mentioned conventional brake fluid pressure control device, the brake operating force from the brake operating member is directly input to the piston rod of the master piston, and during automatic braking, the master piston moves according to the movement of the master piston. The position of the brake operating member also changes automatically. Therefore, when the brake operating member is operated during execution of automatic braking, the relationship between the operation input and the stroke is different from that during normal braking by the brake operation, which may cause a feeling of strangeness.

The present invention has been made in view of the above circumstances, in which the position of the brake operating member is not changed during automatic braking, and the operation input and stroke are changed even when the brake operating member is operated during automatic braking. An object of the present invention is to provide a vehicle brake fluid pressure control device in which the relationship is not changed and the brake operation feeling is improved.

[0006]

In order to achieve the above object, the invention according to claim 1 makes the output hydraulic chamber connected to the wheel brake face the front surface and the boost hydraulic chamber the rear surface. The master cylinder, which is spring-biased in the backward direction, is regulated at the backward limit and slidably fitted in the first cylinder body, and is coaxial with the first cylinder body either integrally or separately. A second cylinder body having a continuously connected second cylinder body, an input port communicating with the hydraulic pressure supply source, an output port communicating with the booster hydraulic pressure chamber, and a release port communicating with the reservoir, and is slidably fitted to the second cylinder body. The pressure regulating valve cylinder to be combined with the retracted position for communicating the output port and the release port and the forward position for communicating the output port and the input port are allowed to slide, and the liquid in the booster hydraulic chamber is allowed. And a sliding member that is fitted to the pressure regulating valve cylinder while the backward limit is regulated so that the reaction force based on the action acts toward the backward position side, and the brake operating force from the brake operating member is moved toward the forward position side. A brake fluid pressure control device for a vehicle, comprising: an input transmission mechanism for transmitting the pressure to the sliding member toward the sliding member, the pressure regulating valve cylinder being slidably fitted to the second cylinder body behind the master piston, The input transmission mechanism having a simulator spring is provided between the sliding member slidably fitted to the pressure regulating valve cylinder and the brake operating member, and the hydraulic pressure supply source is provided through the first opening / closing valve. It is characterized in that the reservoir is connected between booster hydraulic pressure chambers, and the reservoir is connected to the release port via a second opening / closing valve.

According to a second aspect of the present invention, there is provided a master piston which has a front surface facing an output hydraulic chamber connected to a wheel brake and a rear surface facing a boosting hydraulic pressure chamber and is biased in a backward direction by a spring. A master cylinder, which is slidably fitted to the first cylinder body with its retreat limit regulated, a second cylinder body which is coaxially connected to the first cylinder body either integrally or separately, and hydraulic pressure supply. A pressure regulating valve cylinder slidably fitted to a second cylinder body having an input port leading to a power source, an output port leading to the booster hydraulic chamber, and a release port leading to a reservoir; and the output port and Sliding between a retracted position communicating the release port and an advancing position communicating the output port and the input port is enabled, and a reaction force based on the hydraulic pressure of the booster hydraulic chamber acts toward the retracted position. Thus, the sliding member fitted into the pressure regulating valve cylinder while restricting the backward limit, and the input transmission mechanism for transmitting the brake operating force from the brake operating member to the sliding member toward the forward position side. In a vehicle brake fluid pressure control device including: a pressure regulating valve cylinder slidably fitted to a second cylinder body behind the master piston, and slidably fitted to the pressure regulating valve cylinder. Between the sliding member and the brake operating member
The input transmission mechanism having a simulator spring is provided, the hydraulic pressure supply source is connected to the release port via a first opening / closing valve, and the reservoir is connected to the release via a second opening / closing valve. Characterize.

According to the structure of the invention as set forth in claim 1 or 2, the brake operating force corresponding to the brake operation of the brake operating member acts on the sliding member in the forward direction via the input transmission mechanism. The hydraulic pressure from the hydraulic pressure supply source acts on the boosting hydraulic pressure chamber in response to the sliding member sliding to the forward position in the pressure regulating valve cylinder. The hydraulic pressure in the boosting hydraulic pressure chamber acts as a reaction force on the sliding member in the backward direction, and the sliding member moves between the forward movement position and the backward movement position so that the brake operation force and the reaction force are balanced. Then, the boosting hydraulic pressure with the brake operating force amplified accordingly can be obtained in the boosting hydraulic pressure chamber, and the master piston of the master cylinder is actuated by the hydraulic pressure in this boosting hydraulic pressure chamber to increase the boosting force. The applied brake fluid pressure can be applied to the wheel brakes. On the other hand, by controlling the opening and closing of the first and second opening / closing valves during the non-brake operation, the hydraulic pressure of the hydraulic pressure supply source can be adjusted to act on the booster hydraulic pressure chamber, and the master piston is driven by the hydraulic pressure. As a result, the wheel brake can be automatically actuated. At this time, the sliding member is in the retracted limit due to the hydraulic pressure of the boosting hydraulic pressure chamber, and the position of the brake operating member does not change in the non-brake operating state. When the brake operating member is operated in the automatic braking state, the sliding member is pressed to the backward limit position by the reaction force corresponding to the hydraulic pressure of the booster hydraulic chamber, so the brake operating force that overcomes the reaction force is input. Until the sliding member does not move to the forward position, the brake operating member only makes a stroke while compressing the simulator spring, and when the brake operating force is further increased, the brake operating member compresses the simulator spring. According to the stroke, the sliding member slides between the forward movement position and the backward movement position, and the brake fluid pressure of the wheel brake can be further increased.
Thus, the relationship between the operation input and the stroke during operation of the brake operation member during automatic braking does not differ from that during normal braking by the brake operation, the vehicle driver does not feel uncomfortable, and the brake operation feeling Can be improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

1 to 6 show a first embodiment of the present invention. FIG. 1 is a vertical sectional view showing a brake fluid pressure control device in a non-operating state, and FIG. 2 is a brake fluid pressure control shown in FIG. 1 is an enlarged front view of the apparatus, FIG. 3 is an enlarged rear view of the brake fluid pressure control apparatus of FIG. 1, and FIG. 4 is a longitudinal sectional view corresponding to FIG. FIG. 5 is a diagram showing the relationship between the pedal effort and the output hydraulic pressure when the brake pedal is further depressed during automatic braking, and FIG. 6 is a diagram showing the relationship between the pedal effort and the stroke of the brake pedal.

First, referring to FIG. 1, the brake fluid pressure control device is a master cylinder M of a tandem type, for example.
A hydraulic booster 3A for adjusting the hydraulic pressure of the hydraulic pressure supply source 2 to act on the master cylinder M according to the brake operating force input from the brake pedal 1 as a brake operating member, the brake pedal 1 and And an input transmission mechanism 4A interposed between the hydraulic boosters 3A.

The master cylinder M is slidably fitted to a first cylinder body 5 having a bottomed cylindrical shape with a closed front end and a front output hydraulic chamber 6 with its front face facing the first cylinder body 5. Front master piston 8, a front return spring 10 that biases the front master piston 8 toward the rear side, and a rear output hydraulic chamber 7 with its front face facing and sliding on the first cylinder body 5. The rear master piston 9 is fitted as much as possible, and the rear return spring 11 for biasing the rear master piston 9 toward the rear side is provided.

Referring also to FIG. 2, the first cylinder body 5
Has a cylinder hole 5b whose front end is closed by an end wall 5a, and the front master piston 8 forms a front output hydraulic chamber 6 with the end wall 5a and can slide in the cylinder hole 5b. Front output hydraulic pressure passage 1 that is fitted to the front output hydraulic pressure chamber 6
2 is connected to the first cylinder body 5, and the front output hydraulic pressure passage 12 is connected to the wheel brake 14A. An annular front replenishment chamber 15 is formed between the outer periphery of the front master piston 8 and the inner periphery of the first cylinder body 5, and the front replenishment chamber 15 communicates with the reservoir R.

The interior of the reservoir R is divided into a master cylinder storage chamber 16 and a hydraulic pressure source storage chamber 17 by a partition wall 18, and the master cylinder storage chamber 16 has a front storage chamber 16a and a rear storage chamber. A partition wall 19 partitions the storage chamber 16b. The front supply chamber 15 is the front storage chamber 16a.
Be communicated to.

A cup that allows the flow of brake fluid from the front replenishing chamber 15 to the front output hydraulic chamber 6 is provided on the outer periphery of the front master piston 8 between the front replenishing chamber 15 and the front output hydraulic chamber 6. A seal 20 is attached, and an annular seal member 21 that seals between the front supply chamber 15 and the rear output hydraulic chamber 7 is provided on the outer periphery of the front master piston 8 between the front supply chamber 15 and the rear output hydraulic chamber 7. Is installed.

The rear master piston 9 has a cylinder hole 5b.
And a small-diameter piston 23 that slidably fits in the central part of the large-diameter piston 22 in a liquid-tight and slidable manner. Is provided with an engagement flange 23a that engages with the central portion of the front end of the large-diameter piston 22.

The rear output hydraulic chamber 7 is formed in the first cylinder body 5 between the front master piston 8 and the rear master piston 9, and the rear output hydraulic passage communicating with the rear output hydraulic chamber 7 is formed. 13 is connected to the first cylinder body 5, and the rear output hydraulic pressure passage 13 is connected to another wheel brake 14B.

An annular rear replenishment chamber 25 is formed between the outer periphery of the large-diameter piston 22 and the inner periphery of the first cylinder body 5 in the rear master piston 9, and the rear replenishment chamber 25 is located in the rear storage chamber 16b of the reservoir R. Always in communication. Moreover, between the rear replenishing chamber 25 and the rear output hydraulic chamber 7, the rear replenishing chamber 25 to the rear output hydraulic chamber 7 are provided on the outer periphery of the large-diameter piston 22.
A rear seal chamber is provided on the outer periphery of the rear master piston 9 between the boost hydraulic chamber 28 and the rear replenishment chamber 25 in which a cup seal 26 which allows the flow of the brake fluid to the rear master piston 9 is mounted. 25 and boost hydraulic chamber 28
An annular seal member 27 that seals the space is attached.

A first retainer 77 is in contact with the front end of the small-diameter piston 23 in the rear master piston 9, and a second retainer 78 is in contact with the rear end of the front master piston 8. The rear return spring 11 includes the first and second retainers 7
The first and second retainers 77 and 78 are contracted between the seventh and 78, and are substantially fixed to the small-diameter piston 23 and the front master piston 8.

Further, a rod 79 penetrating the central portions of the first and second retainers 77 and 78 so as to be movable in the axial direction is arranged coaxially with the front and rear master pistons 8 and 9, and at the front ends of the rod 79. Is provided with a front engaging collar 79a that engages and abuts from the front side at the center of the second retainer 78, and a rear engaging collar that abuts the center of the first retainer 77 from the rear side at the rear of the rod 79. 79b is provided. Between the front master piston 8 and the rod 79, there is provided a spring 80 for urging the rod 79 rearward so that the front engaging collar 79a is engaged with and brought into contact with the second retainer 78. The spring load is set smaller than that of the rear return spring 11.

As described above, the rear engaging collar 79b of the rod 79 having the front engaging collar 79a engaged with the second retainer 78 engages with the first retainer 77, whereby the front and rear master pistons 8, The maximum interval between 9 is regulated.

The rear end of the rear master piston 9, which is biased rearward by the rear return spring 11, is set at the cylinder hole 5
The partition wall 29, which projects radially inward from the inner surface of b, is regulated by the outer peripheral portion of the large-diameter piston 22 in the rear master piston 9 abutting from the front. Thus, when the rear master piston 9 is in the backward limit, the front master piston 8 is also in the backward limit, and when the front master piston 8 is in the backward limit position, the front output hydraulic chamber 8 is the front storage chamber of the reservoir R. 16
communicate directly with a.

Between the inner circumference of the large-diameter piston 22 and the outer circumference of the small-diameter piston 23 in the rear master piston 9, an annular chamber 81 communicating with the rear supply chamber 25 is formed, and the rear output hydraulic chamber 7 and the annular chamber 81 are formed. An annular seal member 82 that seals the space is attached to the inner circumference of the large-diameter piston 22 so as to slide on the outer circumference of the small-diameter piston 23, and an annular seal member that seals between the boost hydraulic chamber 28 and the annular chamber 81. 83 is mounted on the outer circumference of the small diameter piston 23 so as to be in sliding contact with the inner circumference of the large diameter piston 22.

At the front part of the small diameter piston 23, there is provided a center valve type relief valve 84 which communicates between the annular chamber 81 and the rear output hydraulic chamber 7 in a state where the small diameter piston 23 is in the retracted limit. The relief valve 84 is opened at the central portion of the closed end of a recess 85 provided at the central portion of the front end of the small diameter piston 23 and communicates with the annular chamber 81. And a valve body 87 which is capable of closing the opening end of the hole 86 to the recess 85 and is housed in the recess 85, and is urged rearward by the spring 80, that is, toward the valve hole 86 side. The valve body 87 is formed at the rear end of 79, and the first retainer 77 is provided with a plurality of communication holes 88 that allow the inside of the recess 85 to communicate with the rear output hydraulic chamber 7.

According to such a relief valve 84, the small-diameter piston 23 advances by compressing the rear return spring 11 from the retracted limit position where the large-diameter piston 22 of the rear master piston 9 is in contact with the partition wall 29 and advancing. The valve body 87 is seated on the closed end of the recess 85 and the small diameter piston 23 moves forward while compressing the rear return spring 11 while leaving the large diameter piston 22 in contact with the partition wall 29. 86 is closed and the annular chamber 81 and the rear output hydraulic chamber 7 are shut off. On the other hand, when both the large-diameter piston 22 and the small-diameter piston 23 are in the retracted limit position, the valve body 87 separates from the closed end of the recess 85 to open the valve hole 86,
The annular chamber 81 and the rear output hydraulic chamber 7 are in communication with each other.

Referring also to FIG. 3, hydraulic booster 3A
Is a second cylinder body 30, a pressure regulating valve cylinder 31A slidably fitted to the second cylinder body 30, and a sliding member slidably fitted to the pressure regulating valve cylinder 31A. And a spool valve 32.

The second cylinder body 30 is a master cylinder M.
The first cylinder body 5 is integrally or separately provided coaxially and continuously. In this embodiment, the outer surface of the first cylinder body 5 is flush with the first cylinder body 5. They are installed in a row.

In the second cylinder body 30, a large-diameter hole 30a on the front side and a small-diameter hole 30b on the rear side, which is smaller in diameter than the large-diameter hole 30a, form an annular regulation step portion 30c facing the front. It is provided coaxially so as to be formed between 30a and 30b. In this embodiment, the large-diameter hole 30a has the master cylinder M
Is formed in the second cylinder body 30 so as to have the same diameter and the same diameter as the cylinder hole 5b in the above, and the partition wall 29 provided in the connecting portion of the first and second cylinder bodies 5 and 30 has the cylinder hole 5b and the large diameter hole. It is arranged between 30a. The rear end of the second cylinder body 30, that is, the end opposite to the first cylinder body 5, has a lid member 3 fixed to the second cylinder body 30.
It is liquid tightly closed at 3.

The pressure regulating valve cylinder 31A forms a first opening chamber 24 between itself and the partition wall 29, and the lid member 3 is formed.
The second release chamber 34 is formed between the second cylinder body 3 and
It is slidably fitted in the large-diameter hole 30a of 0, and comes into contact with the regulation step portion 30c from the front side to regulate the backward limit of the pressure regulating valve cylinder 31A. First release chamber 24
Is the atmospheric pressure, and is connected to the hydraulic pressure source storage chamber 17 of the reservoir R in the first embodiment, and the second release chamber 34 is connected to the hydraulic pressure source storage chamber 17 of the reservoir R. To be done.

An annular chamber 36 is formed between the outer circumference of the pressure regulating valve cylinder 31A and the inner circumference of the large diameter hole 30a.
A pair of seal members 37 that seal between the annular chamber 36 and the booster hydraulic pressure chamber 28, and a pair of seal members 38 that seal between the annular chamber 36 and the hydraulic pressure release chamber 34 form a pressure regulating valve cylinder 31A. It is attached to the outer circumference of.

The hydraulic pressure supply source 2 is composed of a pump 39 having a suction port connected to the hydraulic pressure supply source storage chamber 17 of the reservoir R, and an accumulator 40 connected to the discharge port of the pump 39. The hydraulic pressure supply source 2 is connected to the annular chamber 36.

At the center of the pressure regulating valve cylinder 31A,
The first mounting hole 41, the second mounting hole 42 having a larger diameter than the first mounting hole 41, and the first sliding hole 4 having a smaller diameter than the second mounting hole 42.
3 and an annular first step portion 44 facing rearward are provided in the first sliding hole 43.
And a spring accommodating hole 45 formed to have a larger diameter than the sliding hole 43 and an annular second step portion 46 facing the front are formed between the spring accommodating hole 45 and the spring. Accommodation hole 45
The second sliding hole 47 having a smaller diameter than that is provided in order from the front side and over the entire axial length of the pressure regulating valve cylinder 31A.

A disk-shaped elastic member 48 is mounted in the second mounting hole 42 so as to close the front end of the first sliding hole 43. The front portion of the spool valve 32, the rear end of which is slidably fitted in the second sliding hole 46, is slidably fitted in the first sliding hole 43. , Second step 4
6 from the front by contacting the pressure regulating valve cylinder 3
A regulation step portion 32a that defines the retreat limit of the spool valve 32 with respect to 1A is formed. Further, a ring portion 32b which is movable back and forth within the spring accommodating hole 45 is fixed integrally or separately to the rear portion of the spool valve 32, and the spool valve 32 is provided between the ring portion 32b and the first step portion 44. The valve spring 49 for urging the valve toward the rear side is contracted.

The pressure regulating valve cylinder 31A has an annular chamber 3
6, an input port 51 communicating with the hydraulic pressure supply source 2, an output port 52 communicating with the booster hydraulic pressure chamber 28, and a first release chamber 2
4 is provided with a release port 53 communicating with the reservoir R through the input port 51, the input port 51 is opened on the inner surface of the intermediate portion of the first sliding hole 43, and the output port 52 is opened on the inner surface of the front end portion of the spring accommodating hole 45. And the release port 53 becomes the input port 51.
It opens to the inner surface of the first sliding hole 43 in front of.

The output port 5 is provided on the outer circumference of the spool valve 32.
2 is provided with an annular recess 54 which is in constant communication. The spool valve 32 is provided with a passage 55 having one end opened to the outer periphery of the spool valve 32 in front of the annular recess 54 and the other end communicating with the annular recess 54.

The spool valve 32 has a retracted position (position shown in FIGS. 1 and 3) in which the release port 53 is passed through the annular recess 54 communicating with the output port 52 through the passage 55 and an annular recess 54 communicating with the output port 52. It is slidable between the forward position where the input port 51 communicates.

By the way, in the forward position, the front end of the spool valve 32 contacts the elastic member 48. The spool valve 32 bends the elastic member 48 forward and further advances from the forward position. It is also possible.
Further, when the spool valve 32 is in the retracted position, a space 56 is created between the front end of the spool valve 32 and the elastic member 48, but the pressurization and depressurization of the space 56 makes the operation of the spool valve 32 unsmooth. To avoid that
The pressure regulating valve cylinder 31A is provided with a passage 57 for communicating the space 56 with the first release chamber 24.

At the center of the front end of the pressure regulating valve cylinder 31A, the rear end of the pressing piston 58 having a smaller diameter than that of the pressure regulating valve cylinder 31A is coaxially connected integrally or separately. In the embodiment, a small-diameter connecting shaft portion 58a integrally and coaxially provided at the rear end of the pressure piston 58, which is separate from the pressure regulating valve cylinder 31A, has a first mounting hole at the front end of the pressure regulating valve cylinder 31A. It is fitted and fixed to 41 by, for example, press fitting. Moreover, a reaction force chamber 59 communicating with the output port 52 is formed in the pressure regulating valve cylinder 31A between the connecting shaft portion 58a and the elastic member 48.

The pressing piston 58 has its front end facing the boosting hydraulic pressure chamber 28 and can be brought into contact with the rear end of the rear master piston 9 to penetrate the partition wall 29 in a liquid-tight and slidable manner. An annular seal member 61, which is in sliding contact with the outer surface of the pressing piston 58, is attached to the partition wall 29. Further, the output port 5 is provided on the pressing piston 58.
There is provided a communication passage 60 for communicating the reaction force chamber 59 communicating with 2 with the booster hydraulic chamber 28. Moreover, the pressing piston 58 can contact the rear end of the small diameter piston 23 in the rear master piston 9, and the diameter of the pressing piston 58 is set to be equal to or smaller than the diameter of the small diameter piston 23.

The input transmission mechanism 4A is formed in the shape of a cylinder with a bottom, and the stroke cylinder 62A is arranged behind the pressure regulating valve cylinder 31A with the closed end as the front position.
An input piston 63 fitted to the stroke cylinder 62A so as to be slidable relative to each other, and first and second simulator springs 64, 65 connected in series and interposed between the input piston 63 and the stroke cylinder 62A. , Stroke cylinder 62A and pressure regulating valve cylinder 31A
And an opening / closing valve 66 provided therebetween.

The closed end of the stroke cylinder 62A is coaxially connected to the rear end of the spool valve 32 integrally or separately, and in this embodiment, the second sliding hole 4 is formed.
Stroke cylinder 62A with a diameter that can be inserted into
The front end of a shaft portion 62a that is coaxially and integrally provided with the closed end of the spool valve 32 abuts on the rear end of the spool valve 32, and the spring force exerted by the valve spring 49 causes the spool valve 32 and the stroke cylinder 62A to move substantially. It works together.

A stroke liquid chamber 67 is formed between the closed end of the stroke cylinder 62A and the input piston 63. Further, at the front closed end of the stroke cylinder 62A,
A passage 68 that allows the stroke liquid chamber 62 to communicate with the second release chamber 34 is provided, and as long as the stroke liquid chamber 67 communicates with the second release chamber 34, the stroke cylinder 62A
And the axial relative sliding of the input piston 63 is allowed.

The on-off valve 66 closes the stroke valve 62A as it approaches the pressure regulating valve cylinder 31A by further advancing the spool valve 32 from its forward position. When the valve body 69 formed in an annular shape surrounding the opening end of the passage 68 to the front end of the stroke cylinder 62A elastically contacts the rear end of the pressure regulating valve cylinder 31A, the passage 6
8 and the second release chamber 34 are provided at the front end of the stroke cylinder 62A so as to cut off between the second release chamber 34 and the second release chamber 34.

When the opening / closing valve 66 is closed, the stroke cylinder 62A moves forward from the stroke cylinder 62A to the pressure regulating valve cylinder 31A through the valve body 69 of the opening / closing valve 66 in accordance with the forward movement of the stroke cylinder 62A. The stroke cylinder 62A moves forward while applying a force in the forward direction to the pressure regulating valve cylinder 31A when moving forward so as to further move the spool valve 32 from its forward moving position. Is possible.

A piston rod 70, which penetrates the lid member 33 in a liquid-tight manner and slidably, is integrally connected to the input piston 63. A front end of an input rod 71 connected to the brake pedal 1 is swingably connected to a rear portion of the piston rod 70, and a brake operation force corresponding to an operation of the brake pedal 1 is input to the input piston 63, and the brake is applied to the brake. The operating force is from the input piston 63 to the first and second
The simulator springs 64, 65 and the stroke cylinder 62A act on the spool valve 32 toward its forward position.

The piston rod 70 is integrally provided with a flange portion 70a that projects outward in the radial direction so as to face the lid member 33 from the front side, and the rear end of the flange portion 70a is attached to the back surface of the flange portion 70a. The front end of the first spring receiving member 72 penetrating through the collar portion 70a so as to be relatively movable is brought into contact with an engagement step portion 62a provided on the outer periphery of the intermediate portion of the stroke cylinder 62A.

First and second simulator springs 64, 6
The set load of No. 5 is set differently from each other, and the first simulator spring 64 having a small set load is in contact with and engages with the front end of the first spring receiving member 72 and the flange portion 70a. It is contracted between the member 73.

The first spring receiving member 72 is formed with an annular stepped portion 72a facing the front side, and the set load is made larger than that of the first simulator spring 64 to concentrically surround the first simulator spring 64. Second simulator spring 5
6 is contracted between the third spring receiving member 74 and the front end of the first spring receiving member 72, which can come into contact with the stepped portion 72a from the front.

Moreover, the second spring receiving member 73 is formed in such a shape that the collar portion 70a of the piston rod 70 can be abutted from the rear side when the input piston 63 and the piston rod 70 move forward with respect to the stroke cylinder 62A. The third spring receiving member 74 is formed in a shape that allows the second spring receiving member 73, which is pushed forward by the collar portion 70a, to come into contact with the third spring receiving member 74 from the rear side.

The first to third spring receiving members 72,
According to 73 and 74, as the input piston 63 and the piston rod 70 move forward with respect to the stroke cylinder 62A by the brake operation input from the brake pedal 1, the flange portion 70a of the piston rod 70 moves to the first and second positions. The second simulator springs 64 and 65 are sequentially compressed while moving forward.

By the way, this brake fluid pressure control device
Even when the brake pedal 1 is not depressed and the brake is not operated, the automatic brake for applying the brake hydraulic pressure to the wheel brakes 14A and 14B can be executed. Due to the automatic brake, the hydraulic pressure supply source 2 is normally closed. Type solenoid valve is connected to the boost hydraulic pressure chamber 28 via a first opening / closing valve 75, and the reservoir R is connected to the first release chamber 24, that is, a hydraulic booster via a second opening / closing valve 76 which is a normally open solenoid valve. It is connected to the release port 53 of the pressure regulating valve cylinder 31A in 3A.

Next, the operation of the first embodiment will be described. When the hydraulic pressure supply source 2 is normal and a sufficiently high hydraulic pressure is supplied to the hydraulic booster 3A, the brake pedal 1 is operated.
When the brake is operated, the state in which the first opening / closing valve 75 is closed and the second opening / closing valve 76 is opened is maintained, and the piston rod 70 pushed by the input rod 71 is maintained.
Moves forward while compressing the valve spring 49, and the input piston 63
And the stroke cylinder 62A moves forward while keeping the relative position constant. As the stroke cylinder 62A advances, the spool valve 32 of the hydraulic booster 3A advances to the advanced position.

The spool valve 32 is a stroke cylinder 62.
In response to the operation of the brake operating force from A, the hydraulic pressure from the hydraulic pressure supply source 2 is output from the input port 51 of the pressure regulating valve cylinder 31A in accordance with sliding to the forward position in the pressure regulating valve cylinder 31A. It acts on the booster hydraulic chamber 28 via the port 52. The hydraulic pressure of the booster hydraulic pressure chamber 28 acts on the elastic member 48 from the reaction force chamber 59, and the spool valve 32 at the forward position is moved.
A reaction force acts in the backward direction from the elastic member 48, the spool valve 32 moves between the forward movement position and the backward movement position so that the braking operation force and the reaction force are balanced, and the brake operation is performed accordingly. The boosted hydraulic pressure with the amplified force can be obtained in the boosted hydraulic pressure chamber 28, and the hydraulic pressure in the boosted hydraulic pressure chamber 28 causes the rear master piston 9 of the master cylinder M to move.
Can be operated forward, and by further operating the front master piston 8 forward, boosted brake fluid pressure can be applied to the wheel brakes 14A, 14B.

When the brake operating force input from the brake pedal 1 increases, the piston rod 70 moves forward while compressing the first simulator spring 64, and the input piston 6
3 moves forward relative to the stroke cylinder 62A, and brake hydraulic pressure that boosts the brake operating force can be applied to the wheel brakes 14A and 14B.

When the brake operating force input from the brake pedal 1 becomes larger, the piston rod 70
While moving forward while compressing the second simulator spring 65, a booster hydraulic pressure corresponding to a large brake operating force is obtained in the booster hydraulic chamber 28, and a brake hydraulic pressure that boosts the large brake operating force is applied to the wheel brakes 14A, 14B can be operated.

As described above, by combining the first and second simulator springs 64 and 65 having different set loads and connecting them in series, the change of the brake operating force with respect to the stroke of the brake pedal 1 can be changed in a plurality of steps. It can contribute to the improvement of the brake operation feeling.

Moreover, when the hydraulic pressure supply source 2 is normal, the pressure piston 58 is biased rearward by the hydraulic pressure of the boosting hydraulic pressure chamber 28, so that the pressure regulating valve cylinder 31A does not move forward. Since it is not necessary to secure the forward stroke of the pressure regulating valve cylinder 31A, it is possible to make the entire brake fluid pressure control device compact.

Further, when the hydraulic pressure supply source 2 fails, no boosting hydraulic pressure is generated in the boosting hydraulic chamber 28, and the spool valve 3
Since the reaction force in the backward direction does not act on 2, the elastic member 48 is deflected as shown in FIG. 4 after the spool valve 32 moves to the forward position according to the increase of the brake operating force. As the valve 32 further advances from the forward position, the stroke cylinder 62A advances so as to approach the pressure regulating valve cylinder 31A. As a result, the on-off valve 66 closes as the distance between the stroke cylinder 62A and the pressure regulating valve cylinder 31A decreases, and the stroke fluid chamber 67 between the stroke cylinder 62A and the input piston 63 enters the fluid pressure locked state.

When the stroke fluid chamber 67 is in the fluid pressure locked state in this way, the first and second simulator springs 6 are
The operation of the brake pedals 4, 65 is suppressed, and the brake operating force input from the brake pedal 1 is changed to the input piston 6
3 acts on the pressing piston 58 via the stroke cylinder 62A and the pressure regulating valve cylinder 31A. From the pressing piston 58, the rear master piston 9
The pressing force in the forward direction acts on the small-diameter piston 23, which allows the brake fluid pressure to be output from the master cylinder M.

That is, when the hydraulic pressure supply source 2 fails, the first
Also, it is possible to suppress the increase of the invalid stroke and the reaction force by the second simulator springs 64 and 65.

Further, the front surface of the pressure regulating valve cylinder 31A faces the first release chamber 24 communicating with the reservoir R, and the boosting hydraulic pressure chamber 28 is caused by malfunction of the hydraulic pump 39 constituting the hydraulic pressure supply source 2. Even when the fluid pressure of drops to halfway,
The reaction force due to the hydraulic pressure in the booster hydraulic pressure chamber 28 does not significantly affect the pressure regulating valve cylinder 31A and hence the brake pedal 1, and the input loss can be reduced.

Further, since the pressing piston 58 is provided with the communication passage 60 for communicating the reaction force chamber 59 communicating with the output port 52 of the pressure regulating valve cylinder 31A with the boosting hydraulic pressure chamber 28, the liquid of the hydraulic pressure supply source 2 is provided. The passage structure connecting between the output port 52 and the booster hydraulic chamber 28 for guiding the pressure can be simplified.

The rear master piston 9 has a large-diameter piston 22 slidably fitted in the first cylinder body 5, a forward movement corresponding to the forward movement of the large-diameter piston 22, and a forward movement independent of the large-diameter piston 22. Large diameter piston 22
It is composed of a small-diameter piston 23 that penetrates the central part of the liquid-tight in a liquid-tight manner and allows relative sliding. When the hydraulic pressure supply source 2 fails, the small-diameter piston 23 is moved forward so that it is input. The brake fluid pressure obtained in the rear output hydraulic chamber 7 and the front output hydraulic chamber 6 in accordance with the brake operating force can be made higher than in the case of a single rear master piston.

Moreover, since the diameter of the pressing piston 58 that can come into contact with the rear end of the small diameter piston 23 is set to be equal to or smaller than the diameter of the small diameter piston 23, when the hydraulic pressure from the hydraulic pressure supply source 2 drops halfway, That is, the input loss can be reduced by suppressing the volume change amount of the boost hydraulic chamber 28 when a slight hydraulic pressure is generated in the boost hydraulic chamber 28.

Further, in the non-brake operation state, the first opening / closing valve 7
5 is closed and the second opening / closing valve 76 is closed, the hydraulic pressure of the hydraulic pressure supply source 2 can be guided to the boosting hydraulic pressure chamber 28, and the first and second opening / closing valves 75 and 76 are closed. By executing the opening / closing control, the hydraulic pressure of the hydraulic pressure supply source 2 is adjusted to adjust the hydraulic pressure of the booster hydraulic chamber 2.
8 and by driving the rear master piston 9 with the hydraulic pressure thereof, the wheel brakes 14A, 14
B can be automatically braked.

During this automatic braking, the hydraulic booster 3A
The spool valve 32 of the reaction chamber 5 is connected to the booster hydraulic pressure chamber 28.
Due to the action of the hydraulic pressure of 9, the brake pedal 1 is in the backward limit, and the position of the brake pedal 1 does not change in the non-brake operation state.

In the automatic braking state, the brake pedal 1
When the pedal is further pressed, the spool valve 32 is pressed to the backward limit position by the reaction force corresponding to the hydraulic pressure of the booster hydraulic chamber 28, and therefore the spool valve 32 is pushed until the brake operating force that overcomes the reaction force is input. 32 does not move to the forward position, the brake pedal 1 only strokes while compressing the first and second simulator springs 64 and 65,
Even if the pedal effort increases as indicated by the broken line in FIG. 5, the brake fluid pressure is maintained constant during automatic braking as indicated by the solid line in FIG. When the brake operating force is further increased, the brake pedal 1 moves to the first and second simulator springs 64,
The spool valve 32 slides between the forward position and the reverse position in response to the stroke while compressing 65, and the brake fluid pressure of the wheel brakes 14A and 14B can be further increased as shown in FIG.

Thus, the brake pedal 1 during automatic braking
The relationship between the operation input and the stroke at the time of the operation is shown by the solid line in FIG. 6, and is not different from that at the normal brake operation shown by the broken line in FIG. Therefore, the vehicle driver does not feel a sense of discomfort when the brake pedal 1 is pressed further during automatic braking, and the brake operation feeling can be improved.

7 and 8 show a second embodiment of the present invention. FIG. 7 is a longitudinal sectional view of a brake fluid pressure control device in a non-operating state, and FIG. 8 is a brake fluid pressure control of FIG. It is a rear enlarged view of an apparatus.

First, referring to FIG. 7, this brake fluid pressure control device includes a master cylinder M of a tandem type, for example.
And a hydraulic booster 3B for adjusting the hydraulic pressure of the hydraulic pressure supply source 2 to act on the master cylinder M according to the brake operating force input from the brake pedal 1, and between the brake pedal 1 and the hydraulic booster 3B. And an input transmission mechanism 4B interposed in the

The master cylinder M has the same structure as the master cylinder M of the first embodiment, and the input transmission mechanism 4B has a stroke cylinder 62B whose shape is slightly different from that of the stroke cylinder 62A of the first embodiment. Since the input transmission mechanism 4A has the same configuration as that of the input transmission mechanism 4A of the first embodiment except that it is different, detailed description thereof will be omitted.

Referring also to FIG. 8, hydraulic booster 3B
Is a second cylinder body 30, a pressure regulating valve cylinder 31B slidably fitted to the second cylinder body 30 with its front end facing the first release chamber 24, and the pressure regulating valve cylinder 31B.
And a sliding member 92 that is slidably fitted to.

At the center of the pressure regulating valve cylinder 31B,
A mounting hole 93 whose front end is closed and a sliding hole 94 which is coaxially connected to the rear end of the mounting hole 93 and whose rear end is open to the second release chamber 34 are provided. A first restricting flange portion 95a protruding radially inward is provided between front ends of the sliding holes 94, and a second restricting flange portion 95b protruding radially inward is provided at a rear end of the sliding holes 94. To be

The input chamber 96 is installed in the mounting hole 93.
The valve housing 97 is mounted so as to be formed between the input port 51 and the annular chamber 36 that communicates with the hydraulic pressure supply source 2 and the input chamber 96. It is provided. Also, the sliding member 92
Is a stroke cylinder 62 in the input transmission mechanism 4B.
Sliding hole 9 so that the rear end is brought into contact with the front end closed portion of B
4 is slidably fitted into the pressure regulating valve cylinder 31B in the sliding hole 94 between the valve housing 97 and the sliding member 92 that are in contact with the first restricting collar portion 95a. An output chamber 98 is formed that is in constant communication with the port 52.
Further, the sliding member 92 is restricted in its backward movement limit by the second restricting flange portion 95b.

A valve chamber 99 communicating with the input chamber 96 is formed in the valve housing 97, and the output chamber 98 and the valve chamber 9 are formed.
A first valve hole 100 is provided in the valve housing 97 over the space 9 and the first valve seat 101 is formed in the valve housing 97 so as to surround the opening end of the first valve hole 100 on the valve chamber 99 side.
A spherical first valve body 102 that can be seated on the valve is housed in the valve chamber 99, and the first valve body 102 is provided between the valve housing 97 and the first valve body 102.
A valve spring 103 that biases the valve body 102 on the side where the valve body 102 is seated on the first valve seat 101 is provided.

In the state where the first valve body 102 is seated on the first valve seat 101 and the valve chamber 99 and the output chamber 98 are shut off from each other, the valve housing 97 is regulated by the hydraulic pressure of the input chamber 96. The valve housing 97 is pressed against the 95 side and is substantially fixed to the pressure regulating valve cylinder 31B.

A spring 104 that presses the sliding member 92 toward the second restricting flange portion 95b is housed in the output chamber 98, and the sliding member 92 is substantially the stroke cylinder 6
Operates integrally with 2B.

Moreover, one end of the sliding member 92 is connected to the output chamber 9
The second valve hole 105 that can communicate with the first valve hole 100
It is installed coaxially with. On the other hand, pressure regulating valve cylinder 31B
Is provided with a release port 53 that communicates with the first release chamber 24. The release port 53 is configured so as to communicate with the second valve hole 105 with the sliding member 92 in the retracted limit. It is opened at 94.

Further, at the front end of the sliding member 92 which faces the output chamber 98, the second valve seat 10 having a second valve hole 105 opened in the center thereof is provided.
6 is formed, and the spherical second valve body 107 that can be seated on the second valve seat 106 and is accommodated in the output chamber 98 is provided behind the valve shaft 108 that is inserted into the first valve hole 100. The ends are integrally connected, and the front end of the valve shaft 108 is in contact with the first valve body 102.

The valve shaft 108 is integrally provided with a flange portion 108a protruding outward in the radial direction. On the other hand, the valve housing 97 is integrally provided with a guide cylinder part 97a for accommodating the flange part 108a so as to be movable in the axial direction so as to project into the output chamber 98, and the guide cylinder part 97a is provided at the rear end with the guide cylinder part 97a. A restricting flange part 97 that contacts the flange part 108a from the rear side and restricts the backward limit of the valve shaft 108, that is, the second valve body 107.
b is provided, and the valve housing 97 is provided in the guide tube portion 97a.
A spring 109 that biases the valve shaft 108 and the second valve body 107 rearward is provided between the and the flange portion 108a.

At the center of the front end of the pressure regulating valve cylinder 31B, the rear end of the pressing piston 58 having a communication passage 60 for communicating the output port 52 with the booster hydraulic chamber 28, as in the first embodiment described above. Is fitted and fixed, and the pressing piston 5
The front end of the pressing piston 58, which penetrates the partition wall 29 slidably and liquid-tightly, projects into the boosting hydraulic pressure chamber 28 so that the front end of the pressing piston 58 can contact the small-diameter piston 23 of the rear master piston 9.

In such a hydraulic booster 3B, when the hydraulic pressure supply source 2 is normal and a sufficiently high hydraulic pressure is supplied, the sliding member 92 acts on the brake operating force from the stroke cylinder 62B. Depending on the pressure regulating valve cylinder 31
In response to sliding to the forward position in B, the second valve body 10
7 is seated on the second valve seat 106, the first valve body 102 is separated from the first valve seat 101, and the hydraulic pressure from the hydraulic pressure supply source 2 flows from the input port 51 to the input chamber 96 and the first valve hole 100. And acting on the output port 52 via the output chamber 98, and the hydraulic pressure in the output chamber 98, that is, the boost hydraulic chamber 28, acts as a reaction force on the sliding member 92.
Act on. When the sliding member 92 moves to the retracted position, the second valve body 107 separates from the second valve seat 106 and the first valve body 102 sits on the first valve seat 101, so that the output chamber 98 That is, the output port 52 communicates with the first release chamber 24 via the second valve hole 105 and the release port 53.

In this way, as the sliding member 92 moves between the forward movement position and the backward movement position so as to balance the brake operating force and the reaction force, the boosting hydraulic pressure amplified by the brake operating force is applied. It can be obtained in the boost hydraulic chamber 28.

Further, for automatic braking, the release port 5 of the pressure regulating valve cylinder 31A in the hydraulic booster 3A.
The first opening chamber 24 communicating with the first opening chamber 24 is a normally closed solenoid valve.
It is connected to the hydraulic pressure supply source 2 via the opening / closing valve 75, and is connected to the reservoir R via the second opening / closing valve 76 which is a normally open solenoid valve.

According to the second embodiment, when the first and second opening / closing valves 75 and 76 are controlled to be opened / closed in the non-brake operation state, the sliding member 92 of the hydraulic booster 3B is in the backward limit,
Since the release port 53 communicates with the output port 52 via the output chamber 98, the hydraulic pressure of the hydraulic pressure supply source 2 can be adjusted to act on the boost hydraulic chamber 28, and the wheel brake 14 can be operated.
A and 14B can be automatically braked.

During this automatic braking, the hydraulic booster 3B
Of the sliding member 92 of the output chamber 98, that is, the booster hydraulic chamber 28.
The hydraulic pressure is kept pressed to the reverse limit, and the position of the brake pedal 1 does not change in the non-brake operation state.

Therefore, similarly to the first embodiment, the position of the brake pedal 1 does not change in the non-braking operation state during the automatic braking, and the vehicle driver does not press the brake pedal 1 during the automatic braking operation. It is possible to improve the brake operation feeling by preventing the user from feeling uncomfortable.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the claims. It is possible.

For example, the master cylinder may have a single master piston instead of the tandem type.

Further, in the above embodiment, the input transmission mechanisms 4A, 4
Although B has a plurality of, for example, a pair of simulator springs 64 and 65, a single simulator spring may be used.

[0091]

As described above, according to the first or second aspect of the present invention, the position of the brake operating member is not changed during automatic braking, and the operation input is performed even when the brake operating member is operated during automatic braking. The brake operation feeling can be improved by keeping the relationship between the stroke and the stroke unchanged.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a brake fluid pressure control device of a first embodiment in a non-operating state.

FIG. 2 is an enlarged front view of the brake fluid pressure control device of FIG.

FIG. 3 is an enlarged rear view of the brake fluid pressure control device of FIG.

FIG. 4 is a vertical cross-sectional view corresponding to FIG. 1 when a brake is operated when the hydraulic pressure supply source is abnormal.

FIG. 5 is a diagram showing a relationship between a pedaling force and an output hydraulic pressure when a brake pedal is further depressed during an automatic braking operation.

FIG. 6 is a diagram showing a relationship between a pedal effort and a stroke of a brake pedal.

FIG. 7 is a vertical cross-sectional view showing a brake fluid pressure control device of a second embodiment in a non-operating state.

FIG. 8 is an enlarged rear view of the brake fluid pressure control device of FIG.

[Explanation of symbols]

1. Brake pedal as a brake operating member 4A, 4B ... Input transmission mechanism 5: first cylinder body 7 ... Output hydraulic chamber 9 ... Master piston 14B: Wheel brake 28 ... Boost hydraulic chamber 30: second cylinder body 31A, 31B ... Pressure regulating valve cylinder 32 ... Spool valve as sliding member 51 ... Input port 52 ... Output port 53 ... Release port 75 ... First on-off valve 76 ... Second on-off valve 92 ... Sliding member M: Master cylinder R ... Reservoir

Claims (2)

[Claims] 1. A master, which is spring-biased in a backward direction with its output hydraulic chamber (7) connected to a wheel brake (14B) facing its front side and its boost hydraulic chamber (28) facing its rear side. A master cylinder (M) in which a piston (9) is regulated at a backward limit and slidably fitted in a first cylinder body (5), and is coaxial with the first cylinder body (5) integrally or separately. A second cylinder body (30) continuously connected to the input port (51) communicating with the hydraulic pressure supply source (2), an output port (52) communicating with the booster hydraulic chamber (28), and a reservoir (R). ) And a pressure regulating valve cylinder (31A, 31B) slidably fitted to the second cylinder body (30) and having the release port (53) communicating with the output port (52).
And a retracted position in which the release port (53) communicates with each other and a forward position in which the output port (52) and the input port (51) communicate with each other, and the liquid in the booster hydraulic chamber (28) can slide. A sliding member (32) fitted into the pressure regulating valve cylinders (31A, 31B) while restricting the backward limit so that a reaction force based on the pressure acts toward the backward position side, and a brake operating member ( The brake operation force from 1) is directed to the forward position side, and the sliding member (3
2) In the vehicle brake fluid pressure control device including the input transmission mechanism (4A, 4B) for transmitting to the second cylinder body (31A, 31B) behind the master piston (9). 30) is slidably fitted to the pressure regulating valve cylinders (31A, 31B) and is slidably fitted between the sliding member (32) and the brake operating member (1). 64,6
The input transmission mechanism (4A, 4B) having 5) is provided, and the hydraulic pressure supply source (2) is connected to the boost hydraulic chamber (28) via a first opening / closing valve (75), A brake fluid pressure control device for a vehicle, wherein a reservoir (R) is connected to the release port (53) via a second opening / closing valve (76). 2. A master, which is spring-biased in a backward direction with its output hydraulic chamber (7) connected to a wheel brake (14B) facing its front side and its boost hydraulic pressure chamber (28) facing its rear side. A master cylinder (M) in which a piston (9) is regulated at a backward limit and slidably fitted in a first cylinder body (5), and is coaxial with the first cylinder body (5) integrally or separately. A second cylinder body (30) continuously connected to the input port (51) communicating with the hydraulic pressure supply source (2), an output port (52) communicating with the booster hydraulic chamber (28), and a reservoir (R). ) And a pressure regulating valve cylinder (31A, 31B) slidably fitted to the second cylinder body (30) and having the release port (53) communicating with the output port (52).
And a retracted position in which the release port (53) communicates with each other and a forward position in which the output port (52) and the input port (51) communicate with each other, and the liquid in the booster hydraulic chamber (28) can slide. A sliding member (92) fitted into the pressure regulating valve cylinders (31A, 31B) while restricting the backward limit so that a reaction force based on the pressure acts toward the backward position side, and a brake operating member ( The brake operation force from 1) is directed to the forward position side, and the sliding member (9
2) In the vehicle brake fluid pressure control device including the input transmission mechanism (4A, 4B) for transmitting to the second cylinder body (31A, 31B) behind the master piston (9). 30) slidably fitted to the pressure regulating valve cylinders (31A, 31B) slidably fitted between the sliding member (92) and the brake operating member (1). 64,6
The input transmission mechanism (4A, 4B) having 5) is provided, the hydraulic pressure supply source (2) is connected to the release port (53) through a first opening / closing valve (75), and the reservoir (R) is provided. ) Is connected to the release port (53) via a second opening / closing valve (76).