JP2000233740A - Fluid pressure system and brake system using the fluid pressure system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a secure output by an input means in a simple structure, even when the fluid pressure is lost, as well as to set the stroke of the input means in an extreme short stroke. SOLUTION: Solenoid switch valves 46 and 48 are closed by depressing a brake pedal 2, in the normal condition of a pressure source 30, while a master cylinder(MCY) 3 generates an MCY pressure by depressing the brake pedal, and pressure control valves 7 and 8 generate a motive pressure responding to the pedal depressing force by the MCY pressure. The motive pressure is led in to the motive power chamber 41 of an actuator 11, the actuator 11 generates a brake liquid pressure, and wheel cylinders(WCY) 15 and 16; 17 and 18 operate a normal brake by leading in the brake liquid pressure. Since the solenoid switch valves 46 and 48 are opened in the losing condition of the pressure source 30, the MCY pressured generated by depressing the brake pedal is led in to the WCYs 15 and 16; 17 and 18, and the brake is operated even in the losing time of the pressure source 30. The stroke of the brake pedal 2 is made shorter, because it is made as the operating part of the valve plugs of the pressure control valves 7 and 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid pressure booster, such as a negative pressure booster or a hydraulic pressure booster, which boosts an input applied to an input means using a fluid pressure and outputs the boosted output. The invention belongs to the technical field of a hydraulic system having a very short stroke of an input means, and can output reliably with a simple structure in the event of a hydraulic pressure failure. .

[0002] The present invention also belongs to the technical field of a brake system in which the stroke of a brake operating member such as a brake pedal is set to be extremely short, and the brake can be reliably operated with a simple structure in the event of fluid pressure failure. It is.

[0003]

2. Description of the Related Art In an automobile brake system,
2. Description of the Related Art In order to obtain a large braking force even with a small pedal pressing force, conventionally, a fluid pressure booster that boosts the pedal pressing force with a fluid pressure to generate a large output has been often used. As one of such fluid pressure boosters,
There is a negative pressure booster that boosts the pedal effort with a negative pressure to obtain a large output.

FIG. 11 is a sectional view showing a general example of this conventional vacuum booster. In the figure, a is a negative pressure booster,
b is a front shell, c is a rear shell, d is a power piston member, e is a diaphragm, f is a power piston, g
Is a negative pressure chamber, h is a working pressure chamber, i is a valve body, j is an input rod, k is a valve plunger, m is an atmospheric valve seat provided on the valve plunger k, and n is a negative pressure valve provided on the valve body i. Seat, o is a control valve element, p is a control valve, q and r are passage holes, s
Is an output rod, t is a return spring, u is a reaction disk, v is a negative pressure introduction pipe, and w is an air introduction port.

In the conventional vacuum booster a, a negative pressure is always introduced into the negative pressure chamber g via a negative pressure introducing pipe u. In the non-operation state of the negative pressure booster a, the atmospheric valve seat m of the control valve p is in contact with the control valve element o and the control valve element o is slightly separated from the negative pressure valve seat n. Alternatively, the control valve is seated on the negative pressure valve seat n (in the illustrated example, the control valve body o is seated on the negative pressure valve seat n), and the control valve p is in a non-operating state. Therefore, the working pressure chamber h is shut off from the atmosphere and communicates with the negative pressure chamber g through the passage hole r, the gap between the control valve element o and the negative pressure valve seat n, and the passage hole q. A negative pressure is introduced into the working pressure chamber h, or the working pressure chamber h is shut off from both the atmosphere and the negative pressure chamber g.
A pressure slightly higher than that of the negative pressure chamber g, which is opposed to the retarder spring t, is introduced so that the airbag seats on both the atmospheric valve seat m and the negative pressure valve seat n.

In this state, when a brake pedal (not shown) is depressed, the input rod strokes forward (to the left in the drawing), and the control valve element o is seated on the negative pressure valve seat n. Either the control valve element o is released, or the atmospheric valve seat m immediately separates from the control valve element o. That is,
The control valve p is switched. Then, the atmosphere is introduced into the working pressure chamber h from the atmosphere introduction port w through the gap between the control valve body o and the atmosphere valve seat m and the passage hole r. As a result, a predetermined pressure difference is generated between the working pressure chamber h and the negative pressure chamber g, so that the power piston member d and the diaphragm e
The power piston f, which operates, generates an output.
This output is output from valve body i, reaction disc u
The output is transmitted to a master cylinder (not shown) of a brake (not shown) via the output rod s, so that the MCY operates to generate a brake pressure, and the brake is operated by the brake pressure.

[0007] As the pressure in the working pressure chamber h gradually increases, the output of the power piston f increases and the valve body i further advances, so that the control valve body in which the atmospheric valve seat m is seated on the negative pressure valve seat n. It comes into contact with o. As a result, no more air is introduced into the working pressure chamber h, and the pressure in the working pressure chamber h becomes a pressure corresponding to the input (force related to the pedal depression force) applied to the input rod j. The output of the power piston at this time is a large output obtained by boosting the pedal depression force, and as a result, the MCY generates a large brake pressure. At this time, the valve plunger k comes into contact with the reaction disc u, and the reaction disc u
Is elastically deformed by being pinched between the valve body i and the output rod s, and the force generated by the elastic deformation of the reaction disc u is transmitted as a reaction force to the brake pedal via the valve plunger k and the input rod j. Can be

When the brake pedal is released, both the input rod j and the valve plunger k retreat, the atmospheric valve seat m comes into contact with the control valve element o, and the control valve element o separates from the negative pressure valve seat n. Then, the atmosphere introduced into the working pressure chamber h is discharged from the negative pressure introducing pipe v through the passage hole r, the gap between the control valve body o and the negative pressure valve seat n, the passage hole q, and the negative pressure chamber g. Thereby, the power piston f and the valve body i
And the output rod s are retracted to the inoperative position, and the control valve p is inoperative. Thus, in this vacuum booster, a large output can be obtained with a small pedal effort.

[0009]

In recent years, it has been desired in a brake system to shorten the stroke of a brake pedal as much as possible. However, in the above-described conventional negative pressure booster, when the power piston f outputs during operation, the valve body i advances with the advance of the power piston f and the output rod s. For this reason, the control valve p provided with the valve body i also advances greatly, so that the input rod j inevitably also strokes large. Moreover, due to the loss stroke in the brake system prior to the MCY (stroke of the MCY piston until the MCY actually generates the brake pressure),
Valve body i, power piston f and output rod s
Will go further. As a result, the conventional vacuum booster has a large pedal stroke,
It is not possible to meet the aforementioned demand for the shortest possible pedal stroke.

This is because even in the conventional hydraulic booster which boosts the pedal depression force by hydraulic pressure, the control valve is provided on the power piston (not shown). Together with the input rod, the stroke of the input rod, that is, the pedal stroke is increased.

In particular, in the brake in the low G range (reduced speed braking, that is, gentle braking), the idle stroke of the brake cylinder, the master cylinder, and the booster accounts for a large proportion of the pedal stroke. Since it is indispensable to prevent brake dragging, shortening the stroke is even more difficult.

Further, there is a fluid pressure booster in which a control valve is provided in parallel with the power piston in a housing separately from the power piston (for example, Japanese Patent Application Laid-Open No. 09-16493).
No. 8). In this fluid pressure booster, each end of a lever swingably attached to an input rod is swingably connected to a control valve and a power piston, and is controlled via this lever by an input applied to the input rod. The valve and the power piston are actuated. For this reason, since the lever moves forward with the stroke of the power piston during operation, the stroke of the input rod also increases. Moreover, in this fluid pressure booster, the lever is swingably attached to the input rod, the control valve, and the power piston together with a predetermined lever ratio, and the control valve and the power piston are controlled by this lever ratio by an input from the input rod. Therefore, the structure is complicated to control the operation.

On the other hand, as a conventional brake system capable of shortening the pedal stroke, there is a full power brake system. Although not shown, this full-power brake system operates the MCY with the output of the power piston as in the negative pressure booster and the hydraulic pressure booster described above, and introduces the brake pressure generated by the MCY to the brake actuator. Unlike the one that operates the brake by using a power piston, the brake valve is controlled by a brake pedal to control the supply and discharge of a working fluid, and a brake actuator that generates a braking force. The brake is operated by directly introducing the fluid pressure of the fluid pressure source to the brake actuator. In this full-power brake system, the pedal stroke can be made relatively small because the brake valve is simply operated at the time of operation. However, in order to ensure the brake operation by depressing the brake pedal when the fluid pressure source fails. There is a problem that the system becomes complicated.

Therefore, the configuration of the short pedal stroke in the full power brake cannot be simply applied to a hydraulic system having a hydraulic booster having a power piston.

The present invention has been made in view of such circumstances, and an object of the present invention is to make it possible to set a stroke of an input means to an extremely short stroke,
An object of the present invention is to provide a fluid pressure system capable of reliably outputting by an input means with a simple structure even when a fluid pressure has failed.

Further, the stroke of the brake operating member such as a brake pedal can be made extremely short, and the brake can be reliably operated by the brake operating member with a simple structure even when the fluid pressure is lost. It is to provide a braking system.

[0017]

According to a first aspect of the present invention, there is provided a hydraulic pressure system for generating hydraulic pressure during operation, and a stroke which operates upon receiving an input. Input means for controlling the operation of the hydraulic pressure generating cylinder by applying the input to the hydraulic pressure generating cylinder; a pressure source for generating pressure; an actuator for generating an output pressure during operation; It operates by the hydraulic pressure of the cylinder, generates a power pressure in accordance with the hydraulic pressure of the hydraulic pressure generating cylinder, and introduces the pressure from the pressure source to the actuator to operate the actuator. A pressure control valve that disappears and deactivates the actuator, an actuated device that is activated and output with the output pressure from the actuator, the hydraulic pressure generating cylinder and the actuated device. A passage connected to and connected to the passage, when the pressure is normally generated from at least the pressure source and the input means is operated, the passage is shut off, and at least when the pressure source fails, Opening / closing means for communicating with the passage.

Further, the invention according to claim 2 comprises an input detecting means for detecting an input of the input means, a pressure detecting means for detecting a pressure of the pressure source, and a controller for controlling the opening and closing of the opening and closing means. The opening / closing means comprises a normally open or normally closed electromagnetic on / off valve, and the controller controls the electromagnetic on / off valve to detect an input detection signal from the input detection means and a pressure detection signal from the pressure detection means. Switching control to close when at least pressure is normally generated from the pressure source and an input is applied to the input means, and to open at least when pressure is not normally generated from the pressure source. Features.

Further, the invention according to claim 3 is characterized in that the opening / closing means is constituted by a normally-closed opening / closing valve whose opening / closing is controlled by pressure from the pressure source. It is characterized in that it is closed when it is generated, and is opened when pressure is not normally generated from the pressure source. Further, the invention of claim 4 is characterized in that the pressure generated by the pressure source is any one of a negative pressure, a compressed air pressure and a hydraulic pressure.

Further, in the invention according to claim 5, the control valve for automatic operation is provided, and the pressure of the pressure source can be introduced into the actuator via the control valve for automatic operation. When the control valve for automatic operation is operated, the actuator is automatically operated by operating the actuator. Further, the invention according to claim 6 is characterized in that, when the control valve for automatic operation is operated, the power pressure from the pressure control valve can be introduced into the actuator.

Further, the invention of claim 7 is a brake system using the fluid pressure system according to any one of claims 1 to 6, wherein the hydraulic pressure generating cylinder is a master cylinder, and the input means is It is a brake pedal, and the actuated device is a wheel cylinder.

[0022]

In the fluid pressure system of the present invention having such a configuration, when an input is applied to the input means and the input means is operated while the pressure source is normally generating pressure, the opening / closing means is operated. Cuts off a passage directly connecting the hydraulic pressure generating cylinder and the operated device. On the other hand, the operation of the input means causes the hydraulic pressure generating cylinder to generate a hydraulic pressure corresponding to the input of the input means, and the pressure control valve controls the pressure from the pressure source in accordance with the input of the input means. A power pressure is generated according to the input of the means. With this power pressure, the actuator generates an output pressure, and the operated device outputs at this output pressure.

At this time, the amount of fluid discharged from the hydraulic pressure generating cylinder and supplied to the pressure control valve is only required to operate the valve body of the pressure control valve, and the piston stroke of the hydraulic pressure generating cylinder is conventionally reduced. In other words, the stroke becomes much smaller, that is, the operation stroke of the input means becomes smaller, and becomes a very short stroke.

Further, when the pressure source fails, the opening / closing means communicates with a passage directly connecting the hydraulic pressure generating cylinder and the operated device. As a result, the hydraulic pressure generated by the hydraulic pressure generating cylinder by the operation of the input means is introduced into the operated device through this passage, so that the operated device operates and outputs. As described above, in the fluid pressure system of the present invention, even when the pressure source has failed, the operated device can be reliably operated.

On the other hand, in the brake system using the fluid pressure system of the present invention, since the stroke of the input means of the fluid pressure system is a very short stroke,
The pedal stroke of the brake pedal is also a very short stroke. In addition, even when the pressure source fails, the brake can be reliably operated.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically illustrating a first example of an embodiment of a fluid pressure system according to the present invention, and illustrating an example in which the invention is applied to a brake system.

As shown in FIG. 1, a brake system 1 of the first embodiment includes a brake pedal 2 corresponding to input means of the present invention, a tandem type MCY 3 corresponding to a hydraulic pressure generating cylinder of the present invention, and a brake fluid. Reservoir 4, MC to store
In Y3, the first and second M of the first and second brake systems
First and second pressure control valves 7, 8 connected via CY pressure passages 5, 6, respectively, and first and second power pressure passages 9, 10, to these first and second pressure control valves 7, 8, respectively. And second actuators 1 respectively connected via
1, 12, these first and second actuators 11,
12, W of the first and second brake systems connected via first and second brake pressure passages 13 and 14, respectively.
CY15,16; 17,18 (corresponding to the actuated device of the present invention)
It has.

The MCY 3 and the reservoir 4 are the same as the above-mentioned conventional MCYc and the reservoir j, respectively.
Similarly, the brake fluid in the reservoir 4 is supplied to and discharged from the MCY 3 via the same supply / discharge passage as the above-described conventional primary supply / discharge passage j and secondary supply / discharge passage m.

The first and second pressure control valves 7 and 8 are the same, and are disposed in a hole of the housing 19 in a liquid-tight and slidable manner as shown in FIG.
And a control piston 22 which is disposed in a hole of the housing 19 in an airtight and slidable manner and which is actuated via a rod 21 by actuation of the hydraulic piston 20.
A piston spring 23 for constantly biasing the control piston 22 toward the inoperative position shown in the figure, a valve body 26 having an exhaust valve 24 and an air supply valve 25 at both ends thereof, and the valve body 26 A valve spring 27 that constantly biases toward the operating position.

A constant pressure chamber 28 and a variable pressure chamber 29 are defined on both sides of the control piston 22, respectively.
Is constantly communicated with a pressure source 30 (shown in FIG. 1) for generating a negative pressure, and a negative pressure is constantly introduced into the constant pressure chamber 28. Further, the transformation chamber 29 is communicated with the first and second actuators 11 and 12, respectively.

Further, the control piston 22 has an exhaust valve 24
Is provided with an annular first valve seat 31 which can be attached and detached.
A communication hole 32 that communicates with the transformer chamber 29 is formed. Further, the housing 19 is provided with an annular second valve seat 33 on which the air supply valve 25 can be attached and detached, and is located inside the second valve seat 33 to communicate with the variable pressure chamber 29 and the atmosphere. A communicating atmosphere introduction hole 34 is formed.

When the MCY 3 is not operated and the MCY pressure P 'is not generated, the hydraulic piston 20 does not operate, so that the exhaust valve 24 separates from the first valve seat 31 and the air supply valve as shown in the figure. 25 is seated on the second valve seat 33. At this time, the variable pressure chamber 29 communicates with the constant pressure chamber 28 via the communication hole 32 and the variable pressure chamber 29 is shut off from the atmosphere.
, A negative pressure from the pressure source 30 is introduced.

When the MCY3 operates to generate the MCY pressure P ', the MCY pressure P' is applied to the hydraulic piston 20 '.
2, the hydraulic piston 20 operates to the right in FIG. 2, so that the exhaust valve 24 is seated on the first valve seat 31 and the air supply valve 25
Are separated from the second valve seat 33. At this time, the variable pressure chamber 29 is shut off from the constant pressure chamber 28 and communicates with the atmosphere via the air introduction hole 34 so that the atmosphere is introduced into the variable pressure chamber 29. Further, the atmosphere is
Is introduced into the control piston 22, a pressure difference is generated in the control piston 22, and the pressure difference causes the control piston 22 to be pressed toward the inoperative position (to the left in FIG. 2). Control piston 22
When the sum of the force due to the pressure difference that pushes the hydraulic piston 20 toward the inoperative position and the spring force of the piston spring 23 becomes greater than the force that presses the hydraulic piston 20 in the operating direction due to the MCY pressure P ′, the control piston 22 is inoperative. The valve body 26 is also moved back to the inoperative position by the spring force of the valve spring 27, and finally the exhaust valve 24 is moved to the first valve seat 3.
1 and the air supply valve 25 is seated on the second valve seat 33, so that the variable pressure chamber 29 is shut off from both the constant pressure chamber 28 and the atmosphere. That is, the first and second pressure control valves 7, 8 are connected to the pressure in the variable pressure chamber 29, that is, the power pressure generated and output by the pressure control valves 7, 8 is the MCY pressure P '
The pressure (negative pressure) in the transformation chamber 29 is controlled so as to be a pressure corresponding to

First and second actuators 11, 12
Are airtightly and slidably disposed in the hole of the housing 35 as shown in FIG.
8, a power spring 36 which operates at atmospheric pressure receiving the pressure of the atmosphere from the atmosphere 8, a return spring 37 which constantly urges the power piston 36 toward a non-operating position shown in the drawing, and slides in a hole of the housing 35 in a liquid-tight and sliding manner. Movably arranged,
A brake hydraulic pressure generating piston 39 which is operated via a rod 38 by the operation of the power piston 36, and a return spring 40 which constantly urges the brake hydraulic pressure generating piston 39 toward a non-operating position shown in the drawing. .

A power chamber 41 and a constant pressure chamber 42 are defined on both sides of the power piston 36, respectively. As shown in FIG. 1, the atmosphere from the pressure control valves 7 and 8 is introduced into the power chamber 41, and the low-pressure chamber 42 is always in communication with the pressure source 30. A negative pressure is always introduced into 42. In addition, as described later, the atmosphere for automatic braking is introduced into the power chamber 41 when the automatic braking is operated. Further, a hydraulic pressure chamber 43 is defined by a brake hydraulic pressure generation piston 39,
The hydraulic chamber 43 is always in communication with the WCYs 15, 16; When a pressure corresponding to the MCY pressure P ′ from the first and second pressure control valves 7, 8 is introduced into the power chamber 41, the brake hydraulic pressure generation piston 39 operates, and the hydraulic pressure chamber 43 MCY pressure P ', that is, the brake fluid pressure corresponding to the brake pedal 2 (corresponding to the output pressure of the present invention)
Is generated, and the generated brake pressure is WCY15, 16;
Introduced at 17,18, WCY15,16; 17,18 actuate the brakes.

Further, as shown in FIG.
The CY pressure passages 5 and 6 are connected to the first and second brake pressure passages 13 and 14 via first and second MCY pressure direct passages 44 and 45, respectively. These first and second MCY pressure direct passages 44, 45 are provided with first and second solenoid on-off valves 46, 47, respectively. The first and second solenoid on-off valves 46 and 47 are the same, and have an open position I and a closed position II, and are normally set to the open position I as shown in the drawing when not operating. The valve is open.

On the other hand, as shown in FIG. 1, the first and second power pressure passages 9 and 10 are connected to the pressure source 30 via third and fourth power pressure passages 48 and 49, respectively. In that case, the first and second double check valves 50 and 51 are connected to the first and second power pressure passages 9 and 10 and the third and fourth power pressure passages 48 and 49, respectively. Specifically, one input side of the first and second double check valves 50 and 51 is connected to each of the variable pressure chambers 29 of the first and second pressure control valves 7 and 8, respectively. One input side of the double check valves 50 and 51 is connected to the third and fourth power pressure passages 4 respectively.
The output sides of the first and second double check valves 50 and 51 are connected to the power chambers 41 of the first and second actuators 11 and 12, respectively.

Further, the third and fourth power pressure passages 48, 4
9 is provided with first and second automatic brake electromagnetic control valves 52 and 53, respectively. The first and second electromagnetic brake control valves 52 and 53 are the same, and the first and second double check valves 50 and 51 are the same.
A low-pressure (negative-pressure) side connection position I that connects the pressure source 30 to the pressure source 30 and a high-pressure (atmosphere) side connection position II that connects the first and second double check valves 50 and 51 to the atmosphere are set. When not operating, low pressure side connection position I as shown
Is set to

First and second solenoid on-off valves 46, 47 and first and second automatic brake solenoid control valves 52, 53
Are connected to the controller 54. The controller 54 is connected to pedal depression force detection means 55 for detecting a pedal depression force.

The pedal depression force detection by the pedal depression force detection means 55 includes detection of the pedal depression force α itself applied to the brake pedal 2, detection of the bending β of the brake lever 2a, and detection of the reaction force γ at the brake lever pivot point 2b. Detecting the moment δ at the brake lever pivot 2b, pressing the brake lever 2a on the rod 3a connecting the brake lever 2a and the primary piston of the MCY3 (not shown; the same as the conventional MCYc primary piston d of FIG. 11). There is detection of the pressure ε and detection of the axial force の of the rod 3a. Sensors for performing these detections include a tread force load sensor, a load cell, a piezoelectric element, and the like. And
Since these deflection β, reaction force γ, moment δ, pressing force ε, and axial force い ず れ all have a predetermined relationship with the pedal effort, they indicate the pedal effort, although not directly, These values can be used as the pedaling force instead of the pedaling force α itself. Further, there is a detection of the MCY pressure P 'as the pedal depression force detection. This M
As a sensor for detecting the CY pressure P ′, there is a hydraulic pressure sensor or the like.

However, due to the sliding resistance of the brake pedal 2 and the sliding resistance of the piston of the MCY 3 and the like, the relationship between the pedal depression force and the MCY pressure P 'has a hysteresis between operation and return. Since the relationship with the deceleration (brake fluid pressure) is not linear, for example, if the MCY pressure P 'is detected and the brake fluid pressure is controlled based on the MCY pressure P', the brake pressure relative to the pedal depression force is reduced. Linear control cannot be performed. Therefore, it is desirable to detect the pedal depression force as close as possible to the brake pedal 2 or the brake pedal 2 in order to control the brake pressure more linearly.

Further, the controller 54 includes the pressure source 30
The pressure detecting means 56 for detecting the negative pressure of the pressure source 30 is connected, and the detection signal of the negative pressure of the pressure source 30 is input to the controller 54.

The controller 54 determines that the pressure source 30 generates a negative pressure and is normal based on the negative pressure detection signal of the negative pressure source 30 from the pressure detection means 56, and determines whether the pedal depression force detection means 55 is normal. When it is determined that the brake pedal 2 has been depressed and the brake operation has been performed on the basis of the pedal depression force detection signal input from the controller, the first and second solenoid valves 46 and 47 are respectively set to the closed position II and closed. Has become. In contrast, the controller 54
When there is no negative pressure detection signal from the negative pressure source 30 from the pressure detecting means 56 and it is determined that the pressure source 30 has failed without generating a negative pressure, the pedal input from the pedal depression force detecting means 55 Even if it is determined that the brake pedal 2 is depressed based on the pedaling force detection signal and the brake operation is performed, the first and second solenoid valves 46 and 47 are set to be kept at the open positions I respectively. ing.

When the controller 54 determines that the automatic brake operation condition is satisfied based on detection signals from the detection means (not shown) such as the driving condition of the vehicle and the surrounding conditions of the vehicle, the first and second electromagnetic opening / closing are performed. The valves 46 and 47 are respectively set to the closed position II and closed, and the first and second electromagnetic brake control valves 52 and 53 are set to the high pressure side connection position II so that the atmosphere is released from the first and second actuators 1.
The first and second power chambers 41 are respectively introduced. At the time of this automatic braking operation, not shown,
The first and second automatic brake electromagnetic control valves 52 and 53 regulate the atmosphere to a predetermined pressure and introduce the pressure into each power chamber 41, and the first and second actuators 11 and 12 generate a predetermined brake pressure. It has become.

Next, the operation of the thus configured brake system 1 of the first example will be described. 1 to 3 when the brake pedal 2 is not depressed and is not operated.
As shown in (1), the MCY 3 does not generate the MCY pressure P ', and the hydraulic pistons 20 of the first and second pressure control valves 7, 8 do not operate. Therefore, the first and second pressure control valves 7,
8, the exhaust valve 24 is separated from the first valve seat 31, and the air supply valve 25 is seated on the second valve seat 33.
The solenoid on-off valves 46 and 47 are set to the open position I, and the first
The second automatic brake electromagnetic control valves 52 and 53 are both set to the low pressure side position I. In this state, the first
Since the negative pressure from the pressure source 30 is introduced into the power chamber 41 of the first and second actuators 11 and 12 from the variable pressure chamber 29 of the second pressure control valves 7 and 8, the first and second
The actuators 11 and 12 do not operate and do not generate brake fluid pressure. The WCYs 15, 16; 17, 18 are connected to the reservoir 4 via the first and second solenoid valves 46, 47 and the MCY3. Therefore, WCY
15, 16; 17, 18 do not operate the brake.

When the brake pedal 2 is depressed and a normal brake operation is performed, the pedal depression force detecting means 55 detects the pedal depression force in any of the above-mentioned items and outputs a detection signal to the controller 54. Controller 5
4 sets the first and second solenoid on-off valves 46 and 47 to the closed position I based on the detection signal, and sets MCY3 and WCY15,
16; 17, 18 are cut off.

On the other hand, when the brake pedal is depressed, MCY3
When the piston (not shown) moves forward and the liquid chamber (not shown) of MCY3 and the reservoir 4 are shut off, MCY3 becomes MCY3.
A pressure P 'is generated. When detecting the pedal depression force by detecting the MCY pressure P ', the controller 54
The first and second solenoid valves 46 and 47 are closed by the detection signal of the CY pressure P '. Since the generated MCY pressure P 'acts on the hydraulic pistons 20 of the first and second pressure control valves 7, 8, the MCY pressure P'
A pressure corresponding to the pressure P 'is output. The air at this pressure is the first
And the second pressure control valves 7 and 8 are introduced into the power chamber 41 of the first and second actuators 11 and 12 through the first and second double check valves 50 and 51, respectively. As a result, the first and second actuators 11, 12 operate as described above to generate the MCY pressure P ', that is, a brake fluid pressure corresponding to the pedal depression force, and this brake fluid pressure is applied to the WCYs 15, 16, 17 and 18. Introduced, WCY15,
16; 17, 18 normally operate the brake.

During the normal braking operation, the idle strokes of the WCYs 15, 16; 17, 18 are controlled by the first and second actuators 11, 12, which are operated by the power pressures of the first and second pressure control valves 7, 8. The first and second actuators 1 are moved by the stroke of the power piston 36, that is, the stroke of the hydraulic pressure generating piston 39.
It is absorbed by the brake fluid discharged from the first and second hydraulic chambers 43. Therefore, the MCY 3 only needs to discharge the brake fluid for switching the opening and closing of the exhaust valve 24 and the opening and closing of the intake valve 25 of the first and second pressure control valves 7 and 8. For this reason, the piston stroke of the MCY 3 becomes short, and as a result, the pedal stroke of the brake pedal 2 becomes very short as compared with the conventional art, resulting in a very short stroke.

When the brake pedal 2 is returned, the M
Since the CY pressure P 'decreases, the power pressure of the first and second pressure control valves 7, 8 also decreases, and the brake fluid pressure generated by the first and second actuators 11, 12 also decreases.
The braking forces of WCY15,16; 17,18 are weakened. When the brake pedal 2 is released, MCY3
MCY pressure P ′ of the first and second pressure control valves 7 and 8 disappears, and the brake fluid pressure generated by the first and second actuators 11 and 12 also disappears. It is released. In addition, when the brake pedal 2 is released, the pedal depression force disappears.
4 sets the first and second solenoid on-off valves 46 and 47 to the open position I, and the MCY 3 communicates with the WCYs 15, 16; Thus, the brake system 1 is in the non-operating state shown in FIGS.

If the brake operation is performed by depressing the brake pedal 2 in a state where the pressure source 30 has failed, the controller 54 does not receive the negative pressure detection signal from the pressure detection means 56, so that the controller 54 Even if it is determined from the pedal depression force detection signal that the brake operation has been performed, the first and second solenoid on-off valves 46 and 47 are set to be held at the open position I as described above, and the MCY3 and WCY15,
16; 17 and 18 are kept in communication. on the other hand,
In the state where the pressure source 30 has failed, the negative pressure source 30 is not only in the atmospheric pressure state, but also each of the constant pressure chambers 28 and each of the variable pressure chambers 29 of the first and second pressure control valves and the first and second pressure control chambers. Each of the power chambers 41 and each of the constant pressure chambers 42 of the two actuators 11 and 12 are in an atmospheric pressure state.

In this state, when the MCY 3 operates by depressing the brake pedal 2 and generates the MCY pressure P ', each of the exhaust valves of the first and second pressure control valves 7 and 8 is generated by the MCY pressure P'. Even when the power supply valve 24 is seated on the first valve seat 31 and each air supply valve 25 is separated from the second valve seat 33, each power piston 36 of the first and second actuators 11 and 12 does not operate, and the first And second actuators 11, 12
In some cases, no brake fluid pressure is generated. However, in the case of this pressure source failure, the first and second solenoid on-off valves 4
Since 6,47 remains open, the MCY pressure P '
Is introduced into WCY15, 16; 17, 18 through these first and second solenoid on-off valves 46, 47, and WCY15,
16; 17, 18 operate the brake. At this time, MC
The Y pressure P ′ is also introduced into the hydraulic chambers 43 of the first and second actuators 11 and 12, but since the hydraulic pressure generating piston 39 is at the retreat limit of the inoperative position, the hydraulic pressure generating piston 39 Does not further retract due to the MCY pressure P ′ introduced into the hydraulic chamber 43, and there is almost no loss of the MCY pressure P ′ by the first and second actuators 11, 12.
The braking force generated by WCYs 15, 16; 17, 18 can be increased by increasing the pedal depression force to increase the MCY pressure P '.

Thus, the brake can be reliably operated even when the pressure source 30 fails.

The controller 54 controls the first and second solenoid valves 46 and 47 to be kept at the open position I by depressing the brake pedal 2 when the pressure source fails. Regardless of the depression of the brake pedal 2, when it is determined that the pressure source 30 has failed based on the detection signal from the pressure detection means 56, the first and second solenoid valves 46 and 47 are opened. It is also possible to hold it while holding it at the position I.

Further, when the controller 54 determines that the automatic braking operation condition is satisfied based on the driving condition of the vehicle, the surrounding conditions of the vehicle, and the like, as described above, the first and second solenoid on-off valves are determined as described above. 46 and 47 are set to the closed position II, and the first and second electromagnetic brake control valves 52 and 53 are set to the high pressure side connection position II. Then, the atmosphere is introduced into the power chambers 41 of the first and second actuators 11 and 12 through the first and second electromagnetic brake control valves 52 and 53 and the first and second double check valves 50 and 51, respectively. . As a result, a pressure difference occurs between the power chamber 41 and the constant pressure chamber 42, and the power piston 36
Operates, and the first and second actuators 11 and 12 generate the brake fluid pressure, so that the automatic brake operates. At the time of this automatic braking operation, the pressure of the atmosphere introduced into each power chamber 41 of the first and second actuators 11 and 12 is regulated, so that the first and second actuators 11 and 12 operate at a predetermined brake fluid pressure. Occurs, and WCY1
The braking force generated by 5,16; 17,18 is also a predetermined magnitude.

When the automatic brake operating condition is released, the controller 54 sets the first and second solenoid on-off valves 46, 4
7 is set to the open position I, and the first and second electromagnetic brake control valves 52 and 53 are set to the low pressure side connection position I. As a result, the atmosphere in the power chamber 41 is supplied to the pressure source 3 via the first and second double check valves 50 and 51 and the first and second electromagnetic brake control valves 52 and 53.
It is discharged to 0 and the automatic brake is released.

During the automatic brake operation, WCY15, 16;
If you want to further increase the braking force of 17, 18
When the driver depresses the brake pedal 2, the MCY
3 generates the MCY pressure P ', and operates the first and second pressure control valves 7, 8. In this case, the driver presses the brake pedal 2 and the power pressure of the first and second pressure control valves 7 and 8 is adjusted to the atmospheric pressure introduced from the first and second electromagnetic brake control valves 52 and 53. When the stepping is performed so that the pressure becomes higher than the pressure, the atmosphere of the large power pressure of the first and second pressure control valves 7 and 8 is released from the first and second actuators 1.
The power chambers 1 and 12 are introduced into the power chambers 41. As a result, the first and second actuators 11 and 12 generate a brake fluid pressure larger than a predetermined brake fluid pressure generated at the time of the automatic brake operation, and therefore, WCY15, 16;
18 brake force increases. By providing the first and second double check valves 50 and 51 in this manner, it is possible to further increase the braking force during the automatic braking operation from a predetermined braking force during the automatic braking operation.

As described above, according to the brake system 1 of the first example, when the brake is operated, the MCY 3 opens and closes the exhaust valves 24 of the first and second pressure control valves 7, 8 and the intake valve 25.
It is only necessary to discharge the brake fluid for switching between opening and closing, so that the conventional pedal stroke of 60 to 8
A pedal stroke of about 0 to about 15 mm, which is much shorter than 0 mm, can be obtained, and a very short pedal stroke can be realized.

The characteristics of the brake system 1 of the first example are as follows. That is, as shown in FIG. 4A, the relationship between the pedal stroke and the pedal depression force has a steep linear characteristic such that the pedal depression force sharply increases with a slight increase in the pedal stroke. Also, as shown in FIG. 4B, the pedal stroke and the deceleration (that is, the brake fluid pressure)
Similarly, for a slight increase in pedal stroke,
The deceleration (brake fluid pressure) has a steeply linear characteristic that increases sharply. As shown in FIG. 4C, the relationship between the pedaling force and the deceleration (brake fluid pressure) is such that the deceleration (brake fluid pressure) increases in the same manner as the pedal stroke increases, or at 45 °. The linear characteristic is close to 45 °.

As a result of an actual experiment, according to the characteristics shown in FIGS. 4A to 4C, the deceleration (brake fluid pressure) responds straightforwardly according to the increase and decrease of the pedal depression force, and a good driving feeling is obtained. . However, if there is no pedal stroke, the driving feeling is too straightforward and tasteless, so there is no sense of luxury and something unsatisfactory. Therefore, in the brake system 1 of the first example, FIG.
As shown in (e), first, the pedal depression force and the deceleration are increased to the same extent as the conventional one with respect to the increase of the pedal stroke until the predetermined pedal depression force and the predetermined deceleration are obtained. As shown in (a) to (c), the MCY 3, the first and second pressure control valves 7 and 8, the first and second actuators 11 are arranged so that the pedaling force and the deceleration increase sharply with a slight increase in the pedal stroke. , 12, etc. are set. Furthermore, at this time,
If the pedal stroke to the break point at the start of the rapid increase of the pedaling force and deceleration is too short, it becomes unsatisfactory as described above. Therefore, the pedal stroke up to the break point is desirably about 7 mm to 15 mm. However, it is not limited to this,
It may be approximately 0 mm to more than 15 mm. Even if such a break point is provided, the relationship between the pedal depression force and the deceleration (brake fluid pressure) is changed with respect to the pedal depression force so that the linear relationship has no break point as shown in FIG. To control the brake fluid pressure. Thus, FIG.
When the characteristics (d) to (f) are used, a more luxurious and better driving feeling can be obtained as compared with the characteristics shown in FIGS. 4 (a) to 4 (c).

Instead of the first and second double check valves 50 and 51, for example, the power pressures of the first and second pressure control valves 7, 8 and the first and second electromagnetic brake control valves 52, 52, Supply and discharge with the power pressure of 53
Other appropriate selection switching means such as a selection switching valve for selectively performing switching control on the actuators 11 and 12 can be used.

FIG. 5 is a view showing a second example of the embodiment of the fluid pressure system according to the present invention. The same components as in the first example are denoted by the same reference numerals, and a detailed description thereof will be omitted.

Although the first example shown in FIG. 1 uses a negative pressure, the brake system 1 of the second example uses compressed air that is a positive pressure. That is, as shown in FIG. 5, in the brake system 1 of the second example, the pressure source 30 generates a positive pressure (hereinafter, also referred to as air pressure) by compressed air.

The first example of the brake system 1 of the second example
And the second pressure control valves 7 and 8 have an air supply valve 2 respectively.
An air pressure chamber 57 is provided so as to surround the fifth valve seat 33 and the second valve seat 33. The air pressure chamber 57 is connected to the pressure source 30, and the air pressure of the pressure source 30 is constantly introduced. Further, the constant pressure chamber 2 of the first and second pressure control valves 7, 8
Numeral 8 is always in communication with the atmosphere, and constant pressure chambers 42 of the first and second actuators 11 and 12 are also constantly in communication with the atmosphere. In the first and second pressure control valves 7 and 8 of the second example, a seal member for supporting the rod 21 in the housing 19 in an airtight manner becomes unnecessary.

Further, the first and second electromagnetic brake valves 52 and 53 for automatic braking are also set to the low-pressure side connection position I when they are not operated, as in the first embodiment.
In the first embodiment, the first and second double check valves 50 and 51 are respectively connected to the atmosphere. When the first and second automatic brake electromagnetic control valves 52 and 53 are activated, they are set to the high pressure side connection position II.
0 and 51 are respectively connected to the pressure source 30. Other configurations of the brake system 1 of the second example are the same as those of the first example.

In the brake system 1 of the second example configured as described above, at the time of normal braking by depressing the brake pedal 2, the controller 54 receives a detection signal from the pedal depression force detecting means 55 in the same manner as in the first example. Sets the first and second solenoid on-off valves 46 and 47 to the closed position II.
Further, when the brake pedal 2 is depressed, the MCY 3 generates the MCY pressure P 'as in the first example described above, and this MCY pressure P'
And the hydraulic pistons 20 of the first and second pressure control valves 7, 8
Actuates the control piston 22 so that the control piston 22 causes the exhaust valve 24 to be seated on the first valve seat 31 and the air supply valve 25 to be unseated from the second valve seat 33. This allows
The first and second pressure control valves 7, 8 output an air pressure corresponding to the MCY pressure P ', and the air pressure is introduced into the power chambers 41 of the first and second actuators 11, 12, respectively. Thereafter, the normal brake operates in the same manner as in the first example.

When the brake pedal 2 is released, the MCY pressure P 'disappears in the same manner as in the first embodiment, and the air supply valves 25 of the first and second pressure control valves 7, 8 are seated on the second valve seat 33. And the exhaust valve 24 is separated from the first valve seat 31. Thereby, the compressed air of the first and second actuators 11 and 12 is supplied to the first and second double check valves 50 and 51, the variable pressure chambers 29 of the first and second pressure control valves 7 and 8, respectively, and the exhaust valve 24. The air is discharged to the atmosphere through the gap between the control valve 22 and the first valve seat 31, the communication hole 32 of the control piston 22, and the constant pressure chamber 28, and the normal brake is released.

When the pressure source 30 fails, the pressure detecting means 56
The controller 54 sets the first and second solenoid on-off valves 46 and 47 to be kept in the open position I by the detection signal from
MCY3 and WCY15, 16; 17, 18 are kept in communication. Then, similarly to the first example, the brake pedal 2
MCY3 generates the MCY pressure P 'by stepping on
The pressure P 'is introduced into the WCYs 15, 16; 17, 18 through the first and second solenoid on-off valves 46, 47. Therefore, even when the pressure source 30 fails, the brake is reliably operated.

When the automatic braking operation condition is satisfied, the controller 54 sets the first and second electromagnetic opening / closing valves 46 and 47 to the closed position II, as in the first example, and sets the first and second automatic braking electromagnetic valves. The control valves 52 and 53 are set to the high pressure side connection position II. Thereby, the air pressure of the compressed air of the pressure source is adjusted to a predetermined pressure, and is introduced into the power chamber 41 via the first and second double check valves 50 and 51.
Thereafter, the automatic brake is operated in the same manner as in the first example.

When the automatic brake operation condition is released, the controller 54 sets the first and second solenoid valves 46 and 47 to the open position I and sets the first and second automatic brakes similarly to the first example. Electromagnetic control valves 52 and 53 are set at the low-pressure side connection position I. As a result, the air in the power chamber 41 flows through the first and second double check valves 50 and 51 through the first and second electromagnetic brake control valves 52 and 5.
3 to the atmosphere and the automatic brake is released.

In order to further increase the braking force during the operation of the automatic brake, the brake pedal 2
To generate the MCY pressure P ′ in the MCY 3 and increase the brake fluid pressure of the first and second actuators 11 and 12, thereby increasing the braking force.

The other operations of the brake system 1 of the second example are the same as those of the first example. Also, the operation and effect of the brake system 1 of the second example are substantially the same as those of the first example.
The characteristics shown in (d) to (f) are obtained.

FIG. 6 is a view showing a third example of the embodiment of the fluid pressure system according to the present invention. Note that the first and second
The same components as in the example are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the second example shown in FIG. 5 described above, the positive pressure by the compressed air is used, but in the brake system 1 of the third example, the positive pressure by the hydraulic fluid is used. That is, as shown in FIG. 6, in the brake system 1 of the third example, the pressure source 30 generates a positive pressure (hereinafter, also referred to as hydraulic pressure) by the hydraulic fluid. The pressure source 30 of the third example includes a pump 58, an accumulator 59, and a check valve 6.
0 is provided. The pump 58 generates a pump discharge pressure by sucking and discharging the working fluid in the reservoir 61, and the pump discharge pressure is stored in the accumulator 59 as a predetermined hydraulic pressure. The hydraulic pressure stored in the accumulator 59 is prevented from leaking toward the pump 58 by the check valve 60.

The first example of the brake system 1 of the third example
And a second pressure control valve 7, 8 instead of the control piston 22 of each of the above-described examples, a valve piston 62 provided to slide in a liquid-tight manner in the housing 19 as shown in FIG.
It has. At the center of the valve piston 62, a stepped hole 6 composed of a small diameter hole 63 and a large diameter hole 64 extending in the axial direction.
5 are drilled. And the small diameter hole 63 and the large diameter hole 64
A first valve seat 66 is formed in a step portion of the housing 19 between the first and second positions.

Further, in the large-diameter hole 64 of the valve piston 62, a valve body 68 that holds a ball valve 67 that can be attached to and detached from the first valve seat 66 is slidably provided. . The valve body 68 is constantly urged by a spring force of the valve spring 69 in a direction in which the ball valve 67 is seated toward the first valve seat 66. On the other hand, one end of a cylindrical member 70 is fixedly supported by the hydraulic piston 20 and the cylindrical member 7
An intermediate portion of the housing 0 is slidably supported by the housing 19 in a liquid-tight manner. The other end of the cylindrical member 70 enters the small diameter portion 63 of the valve piston 62, and the other end of the cylindrical member 70 faces the ball valve 67. The other end of the cylindrical member 70 is a second valve seat 71 to which the ball valve 67 can be attached and detached. Further, the cylindrical member 70 is provided with a radial hole 73 for constantly communicating the axial hole 72 with the sliding hole 74 of the hydraulic piston 20.

The housing 19 has an accumulator 59
Is provided with an input hole 75 constantly communicating with the
The valve piston 62 is provided with a radial communication hole 76 which constantly communicates the input hole 75 and the large diameter hole 64.
In addition, the housing 19 is always in communication with the small-diameter hole 63 and the first and second double check valves 50 and 5 are connected.
Output holes 77 which are always in communication with each other are formed. Further, the housing 19 is provided with a discharge hole 78 that constantly connects the slide hole 74 and the reservoir 61.

When the brake system 1 is not operated when the brake pedal 2 is not depressed, the hydraulic piston 20 is set at the leftmost retreat position by the spring force of the return spring 79 as shown in FIG. At the same time, the valve piston 62 is set at the leftmost backward limit position by the spring force of the return spring 80. In this non-operating state, the ball valve 67 is seated on the first valve seat
It is away from the valve seat 71. As a result, the output hole 77 is blocked from the input hole 75, the gap between the outer peripheral surface of the cylindrical member 70 and the inner peripheral surface of the small-diameter hole 63, and the ball valve 67.
The second valve seat 71 communicates with the discharge hole 78 via a gap between the second valve seat 71 and the axial hole 72, the radial hole 73, and the sliding hole 74.

When the brake system 1 is operated with the brake pedal 2 depressed, the MCY pressure P 'of the MCY 3 acts on the hydraulic piston 20 in the same manner as in each of the above-described embodiments. , The ball valve 67 is seated on the second valve seat 71 of the tubular member 70, and the output hole 77 is shut off from the discharge hole 78. Next, when the hydraulic piston 20 moves further rightward,
The cylindrical member 70 presses the ball valve 67 to move to the right and separates it from the first valve seat 66, and the output hole 77 is formed between the outer peripheral surface of the cylindrical member 70 and the inner peripheral surface of the small diameter hole 63. , The gap between the ball valve 67 and the first valve seat 66, the large-diameter hole 64, and the radial hole 76 to communicate with the input hole 75.

In this operation, when the input hole 75 and the output hole 77 communicate with each other, the hydraulic pressure is changed from the input hole 75 to the output hole 77.
The valve piston 62 is pressed to the right in FIG. 7 by this hydraulic pressure. Valve piston 3
When the hydraulic pressure for pressing the valve 9 to the right is greater than the spring force of the return spring 80 for pressing the inactive position, the valve piston 39 moves to the right, and finally the ball valve 67.
Are seated on the first and second valve seats 66 and 71, and the output hole 77 is shut off from both the input hole 75 and the discharge hole 78. That is, the first and second pressure control valves 7, 8 of the third example output so that the power pressure of the first and second pressure control valves 7, 8 becomes a pressure corresponding to the MCY pressure P 'of MCY3. The pressure (hydraulic pressure) of the hole 78 is controlled.

As shown in FIG. 8, the first and second actuators 11 and 12 of the brake system 1 of the third example are
First and second actuators 11 and 12 of each of the above examples
However, the third example receives the hydraulic pressure, whereas the third example receives the hydraulic pressure. Therefore, the pressure receiving area of the power piston 36 is larger than that of each of the above examples. It is set small.

In the brake system 1 of the third example having the above-described configuration, when the normal brake operation is performed by depressing the brake pedal 2, the controller 54 receives the detection signal from the pedal depression force detection means 55 in the same manner as in the above-described respective examples. Is the first
And, the second solenoid valves 46 and 47 are set to the closed position II. Also, when the brake pedal 2 is depressed, the MCY 3 generates the MCY pressure P 'in the same manner as in the first example, and the hydraulic pistons 20 of the first and second pressure control valves 7, 8 are generated by the MCY pressure P'. Operate. Then, as described above, the first and second
The pressure control valves 7 and 8 output a hydraulic pressure according to the MCY pressure P ′, and the hydraulic pressure is applied to the first and second actuators 11 and 1.
2 are introduced into the power chamber 41 of the
6 is activated. Thereafter, the normal brake operates in the same manner as in the above-described respective examples.

When the brake pedal 2 is released, the MCY pressure P 'disappears as in the above-described embodiments, so that the hydraulic piston 20 retreats to the non-operating position, and the first and second pressure control valves 7, 8 The ball valve 67 separates from the second valve seat 71 and sits on the first valve seat 66. As a result, the pressure fluids of the first and second actuators 11 and 12 are respectively supplied to the first and second double check valves 50 and 51 and the first and second double check valves 50 and 51, respectively.
Output holes 78 of the pressure control valves 7, 8, a gap between the outer peripheral surface of the cylindrical member 70 and the inner peripheral surface of the small-diameter hole 63, a clearance between the ball valve 67 and the second valve seat 71, 70 axial holes 7
2. Discharged to the reservoir 61 through the radial hole 73, the sliding hole 74, and the discharge hole 78, and the normal brake is released.

When the pressure source 30 fails, the pressure detecting means 56
The controller 54 sets the first and second solenoid on-off valves 46 and 47 to be kept in the open position I by the detection signal from
MCY3 and WCY15, 16; 17, 18 are kept in communication. Then, the MCY 3 generates the MCY pressure P ′ when the brake pedal 2 is depressed in the same manner as in each of the above-described examples.
The CY pressure P 'is introduced into the WCYs 15, 16, 17 and 18 through the first and second solenoid valves 46, 47. Therefore, even when the pressure source 30 fails, the brake is reliably operated.

When the automatic brake operation condition is satisfied, the controller 54 sets the first and second solenoid valves 46 and 47 to the closed position II and sets the first and second automatic brakes as in the above-described embodiments. The electromagnetic control valves 52 and 53 are set to the high pressure side connection position II. Thereby, the accumulator 5
9 is adjusted to a predetermined pressure and introduced into the power chamber 41 of the first and second accumulators 11 and 12 via the first and second double check valves 50 and 51, and the accumulators 11 and 12 Generates brake fluid pressure. Thereafter, the automatic brake is operated in the same manner as in each of the above-described examples.

When the automatic brake operation condition has been released, the controller 54 sets the first and the second as in the above-described embodiments.
The electromagnetic on / off valves 46 and 47 are set to the open position I, and the first and second electromagnetic brake control valves 52 and 53 are set to the low pressure side connection position I. Thereby, the pressure fluid in the power chamber 41 is supplied to the first and second double check valves 50 and 51.
Via the first and second automatic brake electromagnetic control valves 5
The liquid is discharged from the reservoirs 2 and 53 to the reservoir 61, and the automatic brake is released.

In order to further increase the braking force during the automatic braking operation, the MCY pressure P 'is generated in the MCY 3 by depressing the brake pedal 2 in the same manner as in each of the above-described embodiments, and the first and second actuators 11 By increasing the brake fluid pressure of the, 12, the braking force is increased.

The other operations of the brake system 1 of the third example are the same as those of the first example. The operation and effect of the brake system 1 of the third example are also substantially the same as those of the first example.
The characteristics shown in (d) to (f) are obtained. In addition, the reservoir 61 for the pressure source 30 can also be used as the reservoir 4 of the MCY3.

FIG. 9 is a view showing a fourth embodiment of the embodiment of the fluid pressure system according to the present invention. Note that the first to third
The same components as in the example are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the first example shown in FIG. 1 described above, the first and second double check valves 50 and 51 are used to
Although the first and second pressure control valves 7, 8 and the first and second electromagnetic brake control valves 52, 53 are provided in completely independent circuits, in the brake system 1 of the fourth example, FIG. As shown in FIG. 9, first and second electromagnetic brake control valves 52 and 53 connect the first and second pressure control valves 7 and 8 to the first and second actuators 11 and 12, respectively. The second power pressure passages 9 and 10 are provided. Other configurations of the brake system 1 of the fourth example are the same as those of the first example.

In the brake system 1 of the fourth example configured as described above, during normal braking, the brake system 1 operates in the same manner as in the first example. In this case, at the time of the brake operation, the atmosphere of the power pressure of the first and second pressure control valves 7 and 8 is changed to the first and second pressures set at the low pressure side connection position I respectively.
The brakes are introduced into the power chambers 41 of the first and second actuators 11 and 12 through the electromagnetic control valves 52 and 53 for automatic braking, and when the brake operation is released, the powers of the first and second actuators 11 and 12 are released. The air introduced into the chamber 41 is discharged to the pressure source (negative pressure) 30 through the first and second electromagnetic brake control valves 52 and 53 and the first and second pressure control valves 7 and 8, respectively. Is done.

On the other hand, when the first and second automatic brake electromagnetic control valves 52 and 53 are set to the high pressure side connection position II during the automatic brake operation, the atmosphere is changed to the first and second automatic brake electromagnetic control. The pressure is regulated to a predetermined pressure through the valves 52 and 53, and the first and second actuators 11 and 1 are directly adjusted.
When the automatic brake operation is released, the first and second automatic brake electromagnetic control valves 52 and 53 are set to the high pressure side connection position II, and the first and second actuators 11 , 12 are passed through the first and second electromagnetic valves 52 and 53 for automatic braking, respectively, as in the case of releasing the normal brake operation. Pressure control valves 7, 8
Through the pressure source (negative pressure) 30.

In the case of the brake system 1 of the fourth example, when it is desired to increase the braking force during the automatic braking operation, the brake pedal 2 is depressed in the same manner as in each of the above-mentioned examples, whereby the first and second pressure control valves 7 are depressed. , 8 output, the first and second electromagnetic brake control valves 52, 53 are set to the high pressure side connection position II, and the first and second pressure control valves 7, 8 and the first and second actuators are set. The power pressures of the first and second pressure control valves 7, 8 are not introduced into the power chamber 41 because the pressure chambers 11, 12 are shut off. Therefore, the braking force during the automatic braking operation is not increased.

Other operations of the brake system 1 of the fourth example are the same as those of the first example. The operation and effect of the brake system 1 of the fourth example are also substantially the same as those of the first example.
The characteristics shown in (d) to (f) are obtained.

The double check valve is omitted as described above, and the first and second automatic brake electromagnetic control valves 5 are omitted.
Providing 2,53 directly in the first and second power pressure passages 9,10 can also be applied to the brake system 1 by compressed air shown in FIG. 5 and the brake system 1 by hydraulic shown in FIG.

FIGS. 10A and 10B show still another example of the embodiment of the fluid pressure system according to the present invention. FIG. 10A is a partial view showing a fifth example, and FIG. 10B is a partial view showing a sixth example. Partial view,
And (c) is a partial view partially showing the seventh example. Note that the same reference numerals are given to the same components as those in each of the above-described examples, and a detailed description thereof will be omitted.

In the brake system 1 of each example described above, the first and second solenoid on-off valves 46 and 47 are both normally open solenoid valves.
In FIG. 10, as shown in FIG. 10A, the first and second solenoid on-off valves 46 and 47 are both normally closed solenoid valves in which a closed position I and an open position II are set. The first of this fifth example
The second solenoid on-off valves 46 and 47 are always kept at the closed position I when the pressure source 3 is normal, but are opened by the controller 54 when the pressure source 3 fails.
Is set to be switched.

The other structure and other operations of the brake system 1 of the fifth example are the same as those of any of the above-described examples. Further, the operation and effect of the brake system 1 of the fifth example are substantially the same as those of any of the above-described examples, and FIG.
To (f) are obtained.

Further, the normally closed first and second solenoid on-off valves 46 and 47 of the fifth example shown in FIG. 10A are constituted by solenoid valves, and their opening and closing are controlled by the controller 54. On the other hand, in each of the brake systems 1 of the sixth and seventh examples, each of the on-off valves 46 and 47 is not configured by an electromagnetic valve, and the on-off operation is performed by the pressure source 3.
It is controlled at zero pressure. In this case, the sixth example shown in FIG. 10B is an example in which the pressure source 30 generates a negative pressure as in the first example shown in FIG.
Is normal and a negative pressure is generated, the on-off valves 46 and 47 are set to the closed position I. However, when the pressure source 30 fails and no negative pressure is generated, the on-off valves 46 and 47 are Is set to the open position II by the spring force of. The seventh example shown in FIG. 10C is an example in which the pressure source 30 generates a positive pressure as in the second and third examples shown in FIGS. 5 and 6, respectively. When the positive pressure is generated, the on-off valves 46 and 47 are set to the closed position I, but when the pressure source 30 fails and no positive pressure is generated, the on-off valves 46 and 47 are Open position by force II
Is set to

The other configurations and other operations of the brake systems 1 of the sixth and seventh examples are the same as those of the fifth example. The operation and effect of the brake systems 1 of the sixth and seventh examples are substantially the same as those of the fifth example.
The characteristics shown in (d) to (f) are obtained.

In each of the above-described brake systems 1, an automatic brake electromagnetic control valve is provided and the automatic brake system is incorporated to enable automatic braking. However, the present invention is not necessarily limited to this. The electromagnetic control valve for automatic braking is not required and can be omitted.

Further, the hydraulic system of the present invention operates by generating a hydraulic pressure by operating the input means and controlling the hydraulic pressure of the pressure source by the hydraulic pressure, in addition to the brake system as in each of the above-described embodiments. It can be applied to any fluid pressure system that generates hydraulic pressure.

Further, in place of the brake pedal 2 in each of the above-described examples, any other input means such as an operation lever is used as long as the input is operated by an operator such as a driver. You can also.

[0103]

As is apparent from the above description, according to the fluid pressure system of the present invention, the stroke of the input means can be significantly reduced as compared with the conventional one, and the stroke can be made extremely short. By providing a passage for directly connecting the valve and an on-off valve, it is possible to more reliably operate the fluid pressure system even when the pressure source fails.

Further, according to the brake system of the present invention, since such a fluid pressure system is used, the stroke of the brake pedal can be made a very short stroke, the brake feeling can be improved, and the pressure source failure can be improved. At times, the brake system can be operated more reliably.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a first example of an embodiment of a fluid pressure system according to the present invention, and illustrating an example applied to a brake system.

FIG. 2 is a cross-sectional view schematically showing a pressure control valve used in the brake system of the first example shown in FIG.

FIG. 3 is a cross-sectional view schematically showing an actuator used in the brake system of the first example shown in FIG.

FIG. 4 is a diagram showing characteristics of the fluid pressure system according to the present invention.

FIG. 5 is a diagram schematically showing a second example of the embodiment of the present invention.

FIG. 6 is a diagram schematically showing a third example of the embodiment of the present invention.

FIG. 7 is a cross-sectional view schematically showing a pressure control valve used in the brake system of the third example shown in FIG.

8 is a cross-sectional view schematically showing an actuator used in the brake system of the third example shown in FIG.

FIG. 9 is a diagram schematically showing a fourth example of an embodiment of the present invention.

10A is a partial cross-sectional view schematically showing a fifth example of the embodiment of the present invention, FIG. 10B is a partial cross-sectional view schematically showing a sixth example of the embodiment of the present invention, (C) is a partial sectional view schematically showing a seventh example of the embodiment of the present invention.

FIG. 11 is a view schematically showing a conventional general brake system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Brake system, 2 ... Brake pedal, 3 ... Master cylinder (MCY), 4 ... Reservoir, 5 ... 1st MCY
Pressure passage, 6 ... second MCY pressure passage, 7 ... first pressure control valve,
8 ... second pressure control valve, 9 ... first power pressure passage, 10 ... second
Power pressure passage, 11: first actuator, 12: second actuator, 13: first brake pressure passage, 14: second
Brake pressure passage, 15, 16, 17, 18 ... wheel cylinder (WCY), 30 ... pressure source, 44 ... first MCY pressure direct passage, 45 ... second MCY pressure direct passage, 46 ... first solenoid on-off valve, 47 ... 2 electromagnetic on-off valve, 48 ... third power pressure passage, 49 ... fourth power pressure passage, 50 ... first double check valve, 51 ... second double check valve, 52 ... first
Electromagnetic control valve for automatic brake, 53: Second electromagnetic control valve for automatic brake, 54: Controller, 55: Pedal depression force detection means, 56: Pressure detection means 57: Air pressure chamber

Claims (7)

[Claims] 1. A hydraulic pressure generating cylinder for generating hydraulic pressure during operation, and input means for receiving an input to operate and stroke to apply the input to the hydraulic pressure generating cylinder to control the operation of the hydraulic pressure generating cylinder. A pressure source for generating pressure;
An actuator that generates an output pressure during operation; and an actuator that operates at a hydraulic pressure of the hydraulic pressure generating cylinder during operation to generate a power pressure in accordance with the hydraulic pressure of the hydraulic pressure generating cylinder, A pressure control valve for introducing and activating this actuator, disabling the power pressure when not operating, and deactivating the actuator, an actuated device that is operated and output with the output pressure from the actuator, A passage for directly connecting a hydraulic pressure generating cylinder and the actuated device, and a passage provided in the passage when at least pressure is normally generated from the pressure source and when the input means is operated, the passage is shut off. A fluid pressure system comprising: an opening / closing means for communicating the passage at least when the pressure source fails. 2. An input detecting means for detecting an input of the input means, a pressure detecting means for detecting a pressure of the pressure source,
A controller for controlling the opening / closing of the opening / closing means, and the opening / closing means is constituted by a normally open or normally closed electromagnetic opening / closing valve. Based on the detection signal and the pressure detection signal from the pressure detection means, the pressure source is closed at least when pressure is normally generated from the pressure source and an input is applied to the input means. The switching control is performed so as to be opened when no error occurs.
A fluid pressure system as described. 3. The on-off means comprises a normally-closed on-off valve that is controlled to open and close by pressure from the pressure source. The on-off valve closes when pressure is normally generated from the pressure source. 2. The fluid pressure system according to claim 1, wherein the fluid pressure system is opened when pressure is not normally generated from the pressure source. 4. The fluid pressure system according to claim 1, wherein the pressure generated by the pressure source is one of a negative pressure, a compressed air pressure, and a hydraulic pressure. 5. The control valve for automatic operation is provided, and the pressure of the pressure source can be introduced to the actuator via the control valve for automatic operation. The fluid pressure system according to any one of claims 1 to 4, wherein the actuator operates automatically when the actuator operates. 6. The fluid pressure system according to claim 5, wherein a power pressure from the pressure control valve can be introduced to the actuator when the control valve for automatic operation is operated. 7. A brake system using the fluid pressure system according to claim 1, wherein the hydraulic pressure generating cylinder is a master cylinder, the input means is a brake pedal, and A brake system, wherein the actuator is a wheel cylinder.