JP2000142371A - Fluid pressure booster and brake system using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set the stroke of an input means to an extremely short stroke and to positively output through an input means with simple structure even during a fluid pressure failure. SOLUTION: At the time of actuation, a controller 30 controls the actuation of a solenoid proportional valve 26 on the basis of the input of an input piston 5 from an input sensor 28 and working pressure of a working pressure chamber 23 from a pressure sensor 29. A power piston 12 is actuated by the working pressure controlled by the solenoid proportional valve 26 to generate output, and a control piston 18 is actuated by the working pressure to suppress the stroke of the input piston 5, so that the stroke of the input piston 5 becomes a short stroke. However the power piston 12 continues its stroke to generate large output boosting the input of the input piston 5. In the case of the failure of a vacuum source 25, the input piston 5 presses the power piston 12, so that a vacuum booster 1 outputs even during this failure.

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 present invention belongs to the technical field, and particularly to the technical field of a fluid pressure booster in which the stroke of the input means is set to be extremely short, and in the event of a fluid pressure failure, the output can be reliably output with a simple structure.

[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. 8 is a sectional view showing a general example of the 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, n is a negative pressure valve seat provided on the valve body i, o is a control valve body, 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
And an output rod s is transmitted to a not-shown brake master cylinder (hereinafter also referred to as MCY).
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 the fluid pressure booster having the 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 booster that can reliably output by an input means with a simple structure even when the 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 booster for operating a hydraulic pressure booster which outputs an operating pressure based on an operating pressure of a hydraulic pressure. An electromagnetic control valve for performing supply / discharge control of the operating pressure to be actuated and pressure control of the operating pressure, input means for receiving an input during operation, and applying an input to the operating piston when fluid pressure fails, A stroke control unit that operates with a working pressure acting on a piston to suppress a stroke of the input unit, an input detection unit that detects an input applied to the input unit, a pressure detection unit that detects the working pressure, A central processing unit that controls the working pressure by controlling the operation of the electromagnetic control valve based on the input detected by the input detecting means and the working pressure detected by the pressure detecting means. It is characterized by providing, respectively.

Further, according to the present invention, there is provided a working piston for outputting a working pressure by a working pressure by a working fluid pressure, and an electromagnetic control valve for controlling supply / discharge of working pressure applied to the working piston and pressure control of the working pressure. Input means for receiving an input at the time of operation and applying an input to the operating piston in the event of a fluid pressure failure; and a stroke for suppressing the stroke of the input means by operating at an operating pressure acting on the operating piston at the time of operation. Control means, input detecting means for detecting an input applied to the input means, pressure detecting means for detecting the operating pressure, input detected by the input detecting means and operating pressure detected by the pressure detecting means A central processing unit that controls the operating pressure by controlling the operation of the electromagnetic control valve based on the electromagnetic control valve, wherein the electromagnetic control valve comprises an electromagnetic proportional valve or an electromagnetic on-off valve It is characterized by a door. Furthermore, the invention of claim 3 is characterized in that the booster is a negative pressure booster that boosts the input using negative pressure or a hydraulic booster that boosts the input using hydraulic pressure.

Further, the invention according to a fourth aspect of the present invention provides an operating piston which outputs an operation at an operating pressure generated by introducing the atmosphere during operation, an electromagnetic control valve which controls the supply and exhaust of the atmosphere applied to the operating piston, and an input during operation. And input means for applying an input to the working piston at the time of fluid pressure failure; a stroke control piston which operates with a working pressure acting on the working piston during operation to suppress a stroke of the input means; A central processing unit to which an input detecting means for detecting an input of the input means, a pressure detecting means for detecting an operating pressure acting on the working piston, and the input detecting means, the pressure detecting means and a solenoid of an electromagnetic control valve are connected; The operation of the electromagnetic control valve is controlled by the input means, and the output of the control piston operates in opposition to the input from the input means. A valve member provided in series with the operating piston and in contact with the operating piston, a moving member provided to be relatively movable to the valve member, a solenoid for driving the moving member, A valve member that is provided so as to be relatively movable with respect to the valve member and the moving member, wherein the valve member is provided with an atmospheric valve seat, and the moving member is provided with a vacuum valve seat, and further the valve member has A valve portion that can be attached to and detached from the atmospheric valve seat and the vacuum valve seat is provided, and when the central processing unit operates, the central processing unit detects an input of the input unit from the input detection unit and an operating pressure from the pressure detection unit. It is characterized in that the solenoid is controlled based on this.

Further, the invention of claim 5 is characterized in that a stroke setting means capable of arbitrarily setting a stroke of the input means is interposed between the valve member and the input means. Further, the invention of claim 6 is based on the operating pressure and the input so that the central processing unit operates so that the operating pressure acting on the operating piston becomes a pressure corresponding to the input of the input means. The electromagnetic control valve is controlled.

Further, a brake system according to a seventh aspect of the present invention is a hydraulic booster according to any one of the first to sixth aspects, and is operated by an output of the hydraulic booster to generate a brake pressure. And at least a brake master cylinder.

[0022]

In the fluid pressure booster of the present invention having such a configuration, the central processing unit controls the operation of the electromagnetic control valve based on the input given to the input means during operation. The working pressure by the fluid pressure is applied to the working piston, and the working piston is operated to generate an output. At this time, since the operating pressure acting on the working piston also acts on the stroke suppressing means, the stroke suppressing means operates to suppress the stroke of the input means. Thus, the stroke of the input means becomes an extremely short stroke of almost zero. As described above, even if the stroke of the input means is suppressed to a very short stroke, the working piston continues the stroke with the applied working pressure, and a large output is generated by boosting the input of the input means.

Further, the working piston and the input means are arranged to face each other, and the input means abuts on the working piston by moving relative to the working piston.
When the fluid pressure has failed, the working piston is operated by the stroke of the input means. As a result, even when the fluid pressure is lost, the fluid pressure booster does not boost the input but reliably outputs the input. Since the working piston and the input means only need to be arranged facing each other, the structure is extremely simple.

In the brake system of the present invention, since the stroke of the input means of the fluid pressure booster is a very short stroke, the stroke of a brake operating member such as a brake pedal is also set to a very short stroke. become.

In addition, the stroke of the brake operating member can be freely set regardless of the brake system from the master cylinder which is operated by the output of the fluid pressure booster and generates the brake pressure.

Further, since the brake operation is performed by controlling the operation of the electromagnetic control valve of the electromagnetic operation by the central processing unit, the input for the automatic braking operation is supplied to the central processing unit to control the distance between vehicles and the constant speed. It becomes possible to operate the automatic brake in running, stopping and holding, and the like. When the automatic brake is actuated according to the present invention, the brake operation member does not stroke when the automatic brake is actuated, so that the driver does not feel uncomfortable and has a good pedal feeling even when the automatic brake is actuated. Can hold.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view similar to FIG. 8, showing a negative pressure booster as an example of a fluid pressure booster according to the present invention.

As shown in FIG. 1, the fluid pressure booster of this embodiment is a negative pressure booster which boosts an input using negative pressure and outputs the same as the negative pressure booster shown in FIG. The force device 1. The negative pressure booster 1 includes a first shell 2, a second shell 3 connected to the first shell 2 by bayonet, and a third shell 4 connected to the second shell 3 by bayonet. . These first to third shells 2, 3, 4 constitute a housing of the present invention.

An input piston 5 corresponding to the input means of the present invention is passed through the third shell 4 in an airtight and slidable manner. Although not shown, a brake pedal is connected to the rear end of the input piston 5, similarly to a conventional negative pressure booster.

A rear end portion of the output rod 6 is fitted airtightly and slidably on the inner peripheral portion of the front end of the input piston 5, and the front end portion of the output rod 6 is a conventional general negative. Similarly to the pressure booster, a master cylinder (hereinafter, also referred to as MCY) (not shown) is operated by hermetically penetrating the first shell 2.

A piston member 7 is airtightly fitted to the output rod 6, and a flexible diaphragm piston 8 is disposed behind the piston member 7. The inner peripheral edge is supported by the support member 9. The inner peripheral edge of the piston member 7 and the inner peripheral edge of the support member 9 are sandwiched between a nut 10 screwed to the output rod 6 and a flange 11 of the output rod 6, and the diaphragm piston 8 Is hermetically sandwiched between the first and second shells 2 and 3. A power piston 12 is constituted by the piston member 7 and the diaphragm piston 8. And
Power piston 12 and flange 11 of output rod 6
Constitutes the working piston of the present invention.

On the other hand, the input piston 5 has a piston member 1
3 is hermetically fitted and the piston member 1
3 a flexible diaphragm piston 14
The inner peripheral edge of the diaphragm piston 14 is supported by a support member 15. The inner peripheral edge of the piston member 13 and the inner peripheral edge of the support member 15 are
It is sandwiched between a nut 16 screwed to the input piston 5 and a flange 17 of the input piston 5, and the outer peripheral edge of the diaphragm piston 14 is airtightly sandwiched between the second and third shells 3, 4. Have been. The piston member 13 and the diaphragm piston 14 constitute a control piston 18, and the control piston 18 constitutes a stroke suppressing means of the present invention.

A return spring 19 is contracted between the first shell 2 and the power piston 12. The power of the power piston 12 is
And the output rod 6 is constantly biased rearward. A control return spring 20 is contracted between the third shell 4 and the control piston 18, and the control piston 18 is controlled by the spring force of the control return spring 20.
And the input piston 5 is always biased forward. When not operating, the input piston 5 and the output rod 6 are in contact with each other in the axial direction (the left-right direction in FIG. 1), and the projection 21 of the diaphragm piston 8 is in contact with the second shell 3, The input piston 5, output rod 6, power piston 12 and control piston 18 are all shown in FIG.
The retracted position shown in FIG.

In the first to third shells 2, 3, and 4, a first vacuum chamber 22 defined by the first shell 2 and the power piston 12, a second shell 3, the power piston 12, and the control piston 18 are provided. And the second vacuum chamber 2 defined by the third shell 4 and the control piston 18.
4 are provided.

As shown in detail in FIG. 2, the first and second
Both the vacuum chambers 22 and 24 are connected to a negative pressure source 25 such as an intake manifold of an engine, for example, as in a conventional general negative pressure booster, and a negative pressure is constantly introduced.

The working pressure chamber 23 is connected to a negative pressure source 25 via an electromagnetic proportional valve 26 and a check valve 27. The electromagnetic proportional valve 26 constitutes the electromagnetic control valve of the present invention, and is constituted by a conventional well-known three-way electromagnetic proportional valve. When not operated, the working pressure chamber 23 is communicated with the negative pressure source 25 and from the atmosphere side. During operation, the operation pressure chamber 23 is connected to the negative pressure source 2
The air is introduced into the working pressure chamber 23 by shutting off from the side 5 and communicating with the atmosphere side, and the pressure (pressure) in the working pressure chamber 23 is applied to the solenoid of the electromagnetic proportional valve 26 by current (or voltage).
The pressure is controlled so as to be proportional to. Check valve 27 is connected to negative pressure source 2 from working pressure chamber 23.
5 is allowed.

Further, an input sensor 28 for detecting the input of the input piston 5 is provided, and the operating pressure chamber 23
Is provided with a pressure sensor 29 for detecting the operating pressure of.

The input sensor 28 detects an input applied to the input piston 5 based on a pedal depression force. That is, the pedal effort is indirectly detected. As a method of detecting the pedal effort, there are various detection methods such as a method of detecting the pedal effort itself applied to the brake pedal and a method of detecting a rotational torque at the rotation center of the brake pedal.

The electromagnetic proportional valve 26 and the input sensor 28
And the pressure sensor 29 are both central processing units (CP
U: hereinafter also referred to as a controller) 30. The controller 30 detects with the input sensor 28,
Based on the input based on the pedal depression force and the operation pressure of the operation pressure chamber 23 detected by the pressure sensor 29, the electromagnetic proportional valve 2 is controlled so that the pressure in the operation pressure chamber 23 becomes a pressure corresponding to the pedal depression force.
6 is controlled. In that case, the effective pressure receiving area of the control piston 18 is

[0040]

The input is set so as to satisfy the following equation: <effective pressure receiving area × (operating pressure of working pressure chamber 23−negative pressure of second vacuum chamber 24).
The stroke of the input piston 5 hardly occurs.

The operation of the brake system using the negative pressure booster 1 of this embodiment thus configured will be described. When the brake is not actuated when the brake pedal is not depressed, the working pressure chamber 23 is connected to the negative pressure source 25 by the electromagnetic proportional valve 26 and is isolated from the atmosphere, so that the first and second vacuum chambers 22, 24 and working pressure chamber 2
3 are supplied with a negative pressure and have a power piston 1
2, no differential pressure is generated, and the negative pressure booster 1 does not operate.

When the brake pedal is depressed, an input based on the pedal depression force is applied to the input piston 5. The input sensor 28 detects this input and inputs it to the controller 30. Then, the controller 30 controls the operation of the solenoid proportional valve 26 by applying a current (or voltage) corresponding to this input to the solenoid of the solenoid proportional valve 26, and the solenoid proportional valve 26 introduces the atmosphere into the working pressure chamber 23. As a result, a differential pressure is generated in the power piston 12, and the power piston 12 is operated and output, and this output is output from the output rod 6. At this time, since the pressure in the working pressure chamber 23 is detected by the pressure sensor 29 and input to the controller 30, the controller 30 receives the input based on the pedaling force from the input sensor 28 and the working pressure chamber 2 from the pressure sensor 29.
The electromagnetic proportional valve 26 is controlled such that the pressure in the working pressure chamber 23 becomes a pressure corresponding to the input by the working pressure of 3. Therefore, the negative pressure booster 1 generates an output corresponding to the pedal depression force.

On the other hand, due to the air introduced into the working pressure chamber 23, a differential pressure is also generated in the control piston 18, and the control piston 18 is urged rearward by this differential pressure, and the input piston 5 is input to the input. Push backward against this control piston 1
8 is transmitted to the brake pedal as a reaction force.
Further, at this time, since the effective pressure receiving area of the control piston 18 is set as in the above-described formula 1, the input piston 5 hardly makes a stroke by the pressing force of the control piston 18, and as a result, the pedal stroke becomes extremely large. Shortened, resulting in a very short stroke. However, even if the input piston 5 does not make a stroke, the power piston 12 continues to output with the operating pressure of the operating pressure chamber 23, so that the negative pressure booster 1 generates an output boosting the pedal depression force. .

The output of the negative pressure booster 1 activates an MCY (not shown) in the same manner as in a conventional general negative pressure booster, so that the MCY generates brake fluid pressure and activates the brake. In this manner, the brake is applied with the braking force corresponding to the pedaling force.

When the brake pedal is released, the controller 30 controls the proportional solenoid valve 26 in accordance with the decrease in the pedal depression force to exhaust the atmosphere in the working pressure chamber 23 to the negative pressure source 25 side. Reduce pressure. Then, finally, the power piston 12, the control piston 18, and the electromagnetic proportional valve 26 all return to the inoperative position shown in the figure, and the brake is released.

When the negative pressure source 25 fails, the first and second
Atmospheric pressure is introduced into the vacuum chambers 22, 24 and the working pressure chamber 23, and no differential pressure is generated in the power piston 12. Therefore, when an input is applied to the input piston 5 by depressing the brake pedal, an input from the input sensor 28 is input to the controller 30, and even if the controller 30 operates the electromagnetic proportional valve in response to the input, the power is not increased. Piston 1
No. 2 operates because no differential pressure is generated and generates no output.

However, at this time, since the input piston 5 directly presses the power piston 12 and the output rod 6 with the input based on the pedaling force, the output rod 6 operates the MCY. Thus, even when the negative pressure source 25 fails, the brake can be reliably operated.

By the way, in the negative pressure booster 1 of this example,
In operation, the stroke of the input piston 5 is regulated via the control piston 18 by the differential pressure between the working pressure chamber 23 and the second vacuum chamber 24, so that only the power piston 12 and the output rod 6 are stroked, and Since the input piston 5 hardly makes a stroke as described above, the stroke of the input piston 5 becomes significantly smaller than the stroke of the conventional input rod for the same output of the vacuum booster 1, in other words, The pedal stroke is significantly reduced (for example, the stroke is reduced to about 10 mm) as compared with the conventional pedal stroke (about 60 to 80 mm).

Thus, the pedal stroke is considerably smaller than the conventional pedal stroke even for the same pedal effort. Thus, as shown in FIGS. 3A to 3C, in the negative pressure booster 1 of this example, the characteristics of the pedaling force with respect to the pedal stroke, the deceleration with respect to the pedal stroke (that is, the brake pressure or the negative pressure boosting). The characteristics of the output of the device 1 and the deceleration with respect to the pedal depression force (that is, the brake pressure or the negative pressure booster 1)
Characteristic) can be obtained.

FIG. 4 is a sectional view similar to FIG. 2, showing another example of the embodiment of the present invention. 1 and 2
The same reference numerals are given to the same components as in the example shown in FIG.

In the example shown in FIGS. 1 and 2 described above, the control return spring 20 is disposed between the control piston 18 and the third shell 4, and the control return spring 20 is deactivated by the spring force of the control return spring 20. Sometimes, the input piston 5 and the output rod 6 abut against each other in the axial direction. However, in the negative pressure booster 1 of this example, as shown in FIG.
It is arranged between and. The input piston 5 is separated from the output rod 6 in the axial direction when not operated by the spring force of the control return spring 20. Other configurations of the negative pressure booster of this example are the same as those shown in FIGS. 1 and 2.

Next, the operation and effect of the negative pressure booster of this embodiment will be described. In the example shown in FIGS. 1 and 2, before the boosting at the start of operation (that is, before the operation of the electromagnetic proportional valve 26), the forward stroke of the input piston 5 is
The input piston 5, the power piston 12, and the output rod 6 are all stroked. However, in the vacuum booster 1 of this example, the stroke of the input piston 5 in front of the input piston 5 before the start of boosting at the start of operation. On the other hand, only the input piston 5 only strokes, the power piston 12 and the output rod 6 do not both stroke,
It is designed to be held in the inoperative position. Therefore, in the negative pressure booster 1 of this example, since the large power piston 12 and the output rod 6 do not need to be moved before the boosting is started, the pedal feeling at the start of the operation is smaller than that of the examples shown in FIGS. Become good. Other operations and effects of the negative pressure booster of this example are the same as those of the examples shown in FIGS. 1 and 2.

FIG. 5 is a diagram showing a hydraulic booster system using a hydraulic booster according to still another embodiment of the present invention. The same components as those in the above-described examples are denoted by the same reference numerals, and a detailed description thereof will be omitted.

In each of the above-described examples, the negative pressure booster 1 which boosts the input based on the pedal depression force by the negative pressure and outputs the boosted pressure is used, but the fluid pressure booster of this example is a hydraulic pressure booster. Is used.

That is, as shown in FIG. 5, in the hydraulic booster 31, a tubular member 33 is fitted and fixed in a hole of a tubular housing 32 in a liquid-tight and non-slidable manner. The input piston 5 is slidably penetrated through the cylindrical member 33, and the rear end of the input piston 5 is connected to a brake pedal (not shown) as in each of the above-described examples. Further, the front end of the input piston 5 is formed as a control piston portion 18 ', and the control piston portion 18'
3 is fitted in a liquid-tight and slidable manner.

The effective pressure receiving area of the control piston 18 'is substantially the same as in each of the above-described embodiments.

[0057]

[Equation 2] Input <Effective pressure receiving area × (Working pressure chamber 2
3 operating pressure).

A power piston 12 having an output rod 6 is fitted in the hole of the housing 32 in a liquid-tight and slidable manner. The piston 5 is disposed so as to face the front end. Input piston 5 and power piston 1
2, a working pressure chamber 23 is defined,
A control piston return spring 20 is contracted between the input piston 5 and the power piston 12. Therefore, when not operating, the input piston 5 and the power piston 12 are separated from each other by a predetermined distance as in the example shown in FIG.

The pump 3 is connected to the working pressure chamber 23 via an electromagnetic proportional valve 26 and a check valve 27 which are three-way solenoid valves.
The pump 34 is operated by a motor 35 to discharge the working fluid in the reservoir 36 to the working pressure chamber 23. Further, an accumulator 37 in which a predetermined pressure is accumulated is provided between the electromagnetic proportional valve 26 and the check valve 27.
Further, a hydraulic pressure sensor 29 'for detecting the pressure of the working pressure chamber 23
And a hydraulic pressure sensor (not shown) for detecting the accumulated pressure of the accumulator 37 is provided.
These hydraulic pressure sensors are both connected to the controller 30.

Further, the remaining ports of the proportional solenoid valve 26 are connected to a reservoir 36. The electromagnetic proportional valve 26 connects the working pressure chamber 23 to the low-pressure side reservoir 36 (the negative pressure source 25 in each of the above-described examples) when not operating, as in the above-described respective examples, and the high-pressure-side pump 34 and the accumulator 37. (In the above-described examples, the atmosphere). During operation, the working pressure chamber 23 is cut off from the low pressure side reservoir 36 and connected to the high pressure side pump 34 and the accumulator 37.
Other configurations of the brake system using the hydraulic booster 31 of this example are the same as those of the above-described respective examples.

In the brake system of this embodiment configured as described above, the controller 3 is controlled based on the detected pressure from the hydraulic pressure sensor for detecting the accumulated pressure of the accumulator 37.
When the accumulated pressure of the accumulator 37 is lower than the predetermined pressure, the pump 35 is driven by driving the motor 35 to increase the accumulated pressure of the accumulator 37 to the predetermined pressure or more. When the accumulated pressure of the accumulator 37 is equal to or higher than the predetermined pressure, the controller 30 stops the motor 35 and the pump 34, and stops increasing the pressure of the accumulator 37. In this way, the accumulator 37 is constantly storing a predetermined pressure. When the brake is not operated, the brake system is in the illustrated state, no hydraulic pressure is introduced into the operating pressure chamber 23, and the pistons 5, 12 are set at the retreat limit positions.

When the brake operation is performed by depressing the brake pedal, the controller 30 controls the operation of the electromagnetic proportional valve 26 based on the input of the input piston 5 detected by the input sensor 28, as in the above-described embodiments. The accumulated pressure of the accumulator 37 is introduced into the pressure chamber 23. As a result, the power piston 12 operates and outputs, and the output activates the MCY via the output rod 6 to operate the brake. At this time, the controller 30 controls the electromagnetic proportional valve 26 based on the input from the input sensor 28 and the operating pressure from the hydraulic pressure sensor 29 'so that the operating pressure of the operating pressure chamber 23 becomes a pressure corresponding to the pedal depression force. Is controlled, so that the brake can be applied with the braking force according to the pedaling force.

The operating pressure in the operating pressure chamber 23 presses the control piston portion 18 'rearward, that is, in the direction in which it is to be pushed back, and this pressing force is transmitted to the brake pedal as a reaction force. Further, since the effective pressure receiving area of the control piston portion 18 'is set so as to satisfy Expression 2, the input piston 5 hardly makes a stroke at this operating pressure as in each of the above-described examples, and the pedal stroke becomes smaller than before. It is greatly reduced in comparison.

When the brake pedal is released, there is no input, so the controller 30 controls the electromagnetic proportional valve 26 to a non-operating state, as in the above-described embodiments. As a result, the working fluid in the working pressure chamber 23 is discharged to the reservoir 36, the power piston 12 returns to the non-operating position, and the brake is released.

When the hydraulic pressure source such as the pump 34, the motor 35 or the accumulator 37 fails, the input piston 5 pushes the power piston 12 and the output rod 6 in the same manner as described above. Is reliably applied. Other functions and effects of the brake system of this embodiment are the same as those of the above-described embodiments.

As the electromagnetic control valve of the present invention, two conventionally-known electromagnetic on-off valves can be used instead of the electromagnetic proportional valve 26 in each of the above-described examples. That is, in the negative pressure booster 1 of the example shown in FIGS.
A conventionally well-known normally-open electromagnetic on-off valve is provided in a passage connecting the pressure source 25 and the negative pressure source 25, and a conventionally-known normally-closed electromagnetic on-off valve is conventionally provided in a passage connecting the working pressure chamber 23 and the atmosphere. In the hydraulic booster 31 of the example shown in FIG.
A conventionally well-known normally-open electromagnetic on-off valve is provided in a passage connecting the reservoir 3 and the reservoir 26, and a conventionally-known normally-closed electromagnetic on-off valve is conventionally provided in a passage connecting the working pressure chamber 23 and the accumulator 37. These solenoid on-off valves are connected to the controller 30
The opening and closing of the hydraulic fluid chamber 2 is controlled in the same manner as described above.
The hydraulic pressure of 3 can also be controlled.

FIG. 6 is a diagram schematically showing still another example of the embodiment of the present invention. As shown in FIG. 6, the brake system of this example uses a vacuum booster 1, and this vacuum booster 1 has a shell 2 (1 in FIG.
Is shown with two shells 2, but as in the previous example, the first
Or third shells 2, 3, and 4).

In the shell 2, a cylindrical movable iron core 38 is provided.
Are disposed so as to be relatively movable with respect to the shell 2, and the movable iron core 38 has an inner cylindrical portion 38a and an outer cylindrical portion 38b.
Thus, it is formed as a concentric double cylindrical member. A valve member 39 is slidably provided on the inner peripheral surface of the inner cylindrical portion 38a. The input rod 5 corresponding to the input means of the present invention is integrally provided to project rearward from the rear end (left end in FIG. 6) of the valve member 39. The input rod 5 projects outward from the shell 2 and has a rear end connected to a brake pedal (not shown).

The rear end of the output rod 6 is fitted airtightly and slidably on the inner periphery of the front end of the valve member 39. The front end of the output rod 6
Y is activated.

A piston member 7 is air-tightly fitted and fixed to the output rod 6, and a flexible diaphragm piston 8 is disposed behind the piston member 7. Is attached to the output rod 6, and the outer peripheral edge of the diaphragm piston 8 is hermetically attached to the shell 2. Then, the valve member 39 of the output rod 6
The working piston of the present invention is constituted by the sliding portion of the power piston 12, the mounting portion of the power piston 12, and the power piston 12.

On the other hand, the piston member 1 is
3 is airtightly fitted and fixed, and a flexible diaphragm piston 14 is disposed in front of the piston member 13.
The inner peripheral edge of the diaphragm piston 14 is attached to the valve member 39, and the outer peripheral edge of the diaphragm piston 14 is
It is mounted airtight. A control piston 18 is constituted by the piston member 13 and the diaphragm piston 14.

Further, a flexible diaphragm piston 40 is provided on the cylindrical movable iron core 38, and the inner peripheral edge of the diaphragm piston 40 is attached to the outer peripheral surface of the outer cylindrical portion 38 b of the movable iron core 38. The outer peripheral edge of the diaphragm piston 40 is hermetically attached to the shell 2.

Further, a cylindrical valve element 41 is fitted airtightly and slidably on the inner peripheral surface of the outer cylindrical section 38b of the movable iron core 38. The valve section 41a of the valve element 41 is , An atmospheric valve seat 39 a provided on the valve member 39 and a movable iron core 38.
Valve seat 38c provided at the rear end of the inner cylindrical portion 38a
It is possible to take on and take off. The valve body 41 is constantly urged toward the atmosphere valve seat 39a and the vacuum valve seat 38c by the spring force of a valve spring 48 contracted between the valve body 41 and the shell 2.

A return spring 19 is contracted between the shell 2 and the power piston 12, and the power piston 12 and the output rod 6 are constantly urged rearward by the spring force of the return spring 19. When not operating, the valve member 39 and the output rod 6 come into contact with each other in the axial direction (left-right direction in FIG. 6), and the valve member 39, the input rod 5, the output rod 6, the power piston 12, and the control piston 18 Are in the retreat limit position shown in FIG.

Inside the shell 2, a first vacuum chamber 22 defined between the shell 2 and the power piston 12, an operating pressure chamber 23 defined between the power piston 12 and the control piston 18, and Second vacuum chambers 24 are provided between the control piston 18 and the diaphragm piston 40, respectively. The first and second vacuum chambers 22 and 24 are connected via a passage hole 42 formed in the output rod 6, a space 43 between the valve member 39 and the output rod 6, and a passage hole 44 formed in the valve member 39. Are always in communication with each other. Further, the inner cylindrical portion 3 of the working pressure chamber 23 and the movable iron core 38
The inner peripheral surface 8a is always in communication with the inner peripheral surface of the valve member 39 via an axial passage hole 45 provided in the valve member 39.

The first vacuum chamber 22 is connected to a negative pressure source 25 such as, for example, an intake manifold of an engine, similarly to a conventional general negative pressure booster.
A negative pressure is always introduced into the vacuum chambers 22 and 24. An air inlet 46 is provided in a portion of the shell 2 through which the input rod 5 passes.

Further, the outer periphery of the shell 2 is provided with a movable iron core 3.
8 is provided.
Accordingly, when the solenoid coil 47 is not excited, the movable iron core 38 is provided with a diaphragm piston generated by a differential pressure between the atmospheric pressure acting on the left side surface of the diaphragm piston 40 and the negative pressure of the second vacuum chamber 24 acting on the right side surface. At the output of 40, it is set to the advanced inoperative position shown in the figure. When the solenoid coil 47 is excited, the movable iron core 38 is moved rearward against the output of the diaphragm piston 40.

An atmosphere valve 49 is constituted by the valve portion 41a of the valve element 41 and the atmosphere valve seat 39a.
Reference numeral 9 denotes a normally closed valve in which the valve portion 41a of the valve element 41 is seated on the atmospheric valve seat 39a by the spring force of the valve spring 48 when the valve element 41 is not operated.
When the air valve 49 is opened away from the air inlet a, the air flows from the air inlet 46 to the valve portion 41a of the valve body 41 and the air valve seat 39a.
, The inner peripheral surface of the inner cylindrical portion 38a, and the axial passage hole 45 to be introduced into the working pressure chamber 23.

The valve portion 41a of the valve body 41 and the vacuum valve seat 3
8c constitute a vacuum valve 50, and this vacuum valve 50
When the diaphragm piston 4 is not operated as shown in FIG.
The vacuum valve seat 38c is a normally open valve that is separated from the valve portion 41a of the valve body 41 at the position where the movable core 38 advances at the output of 0, and thus the vacuum valve seat 38c is connected to the valve portion 41 of the valve body 41.
a, the vacuum valve 49 is open and the negative pressure source 2
5, the first vacuum chamber 22, the passage hole 42, the space 43,
Passage hole 44, second vacuum chamber 24, hole 38 of movable iron core 38
d, the pressure is introduced into the working pressure chamber 23 through a gap between the valve portion 41a of the valve body 41 and the vacuum valve seat 38c and an axial passage hole 45. And the solenoid coil 4
7. The atmospheric control valve 49 and the vacuum valve 50 constitute an electromagnetic control valve of the present invention.

Further, an input sensor 28 for detecting the input of the input rod 5 is provided, and a pressure sensor 29 for detecting the working pressure of the working pressure chamber 23 is provided. The input sensor 28 detects an input that is given to the input rod 5 and is based on a pedaling force. That is,
The pedal force is indirectly detected. As a method of detecting the pedal effort, there are various detection methods such as a method of detecting the pedal effort itself applied to the brake pedal and a method of detecting a rotational torque at the rotation center of the brake pedal.

The solenoid coil 47, the input sensor 28 and the pressure sensor 29 are all connected to the controller 30 which is a central processing unit. The controller 30 detects the input based on the pedal depression force detected by the input sensor 28 and the operating pressure chamber 23 detected by the pressure sensor 29.
, The excitation of the solenoid coil is controlled so that the pressure in the working pressure chamber 23 becomes a pressure corresponding to the pedaling force. In that case, the control piston 18
Is set so as to satisfy the above-described formula 1, so that the stroke of the input rod 5 hardly occurs during operation. Another configuration of the negative pressure booster 1 of this example is the same as that of the negative pressure booster 1
Is the same as

The operation of the brake system using the thus configured negative pressure booster 1 of this embodiment will be described. When the brake is not operated when the brake pedal is not depressed, the normally closed atmospheric valve 49 is closed and the normally open vacuum valve 50 is open as shown in the figure. Thus, the working pressure chamber 23 communicates with the second vacuum chamber 24, and further communicates with the negative pressure source 25 via the first vacuum chamber 22. Therefore,
A negative pressure is introduced into the working pressure chamber 23, so that no differential pressure is generated between the power piston 12 and the control piston 18,
These power piston 12 and control piston 18 do not operate at all.

When the brake pedal is depressed, an input is given to the input rod 5 based on the pedal depression force.
The input sensor 28 detects this input and
To enter. Then, the controller 30 applies a current (or voltage) corresponding to the input to the solenoid coil 47 to excite the solenoid coil 47. By the excitation of the solenoid coil 47, the movable iron core 38 moves rearward, the vacuum valve seat 38c contacts the valve portion 41a of the valve body 41, and the vacuum valve 50 closes. Therefore, the working pressure chamber 23 is shut off from the first vacuum chamber 24.

When the movable core 38 moves further backward, the vacuum valve seat 38c of the movable core pushes the valve portion 41a of the valve body 41 backward against the spring force of the valve spring 48, so that the valve portion 41a When the user releases the seat 39a, the atmosphere valve 49 opens. Then, since the atmosphere is introduced into the working pressure chamber 23 as described above, a differential pressure is generated in the power piston 12, the power piston 12 is operated and output, and this output is output from the output rod 6. At this time, since the pressure in the working pressure chamber 23 is detected by the pressure sensor 29 and input to the controller 30, the controller 30 receives the input based on the pedal depression force from the input sensor 28 and the working pressure chamber 23 from the pressure sensor 29. , The excitation of the solenoid coil 47 is controlled so that the pressure in the working pressure chamber 23 becomes a pressure corresponding to the input. Therefore, the negative pressure booster 1 generates an output corresponding to the pedal depression force. When the pressure in the working pressure chamber 23 reaches a pressure corresponding to the input, the controller 30
Controls the excitation of the solenoid coil 47 so that the differential valve 49 and the vacuum valve 50 are both closed.

On the other hand, due to the atmosphere introduced into the working pressure chamber 23, a differential pressure is also generated in the control piston 18, and the control piston 18 is urged rearward by this differential pressure, and the valve member 39 is input to the input. Push backward against this control piston 1
8 is transmitted to the brake pedal as a reaction force.
At this time, since the effective pressure receiving area of the control piston 18 is set as in the above-described formula 1, the pressing force of the control piston 18 causes the valve member 39 and the input rod 5 to move.
Hardly strokes, resulting in a very short pedal stroke, a very short stroke. However, even if the valve member 39 and the input rod 5 do not make a stroke, the power piston 12 continues to output with the operating pressure of the operating pressure chamber 23, so the negative pressure booster 1 boosts the pedal depression force. Generate output.

The output of the negative pressure booster 1 activates an MCY (not shown), similarly to a conventional general negative pressure booster, so that the MCY generates a brake fluid pressure and activates a brake. In this manner, the brake is applied with the braking force corresponding to the pedaling force.

When the brake pedal is released with both the atmosphere valve 49 and the vacuum valve 50 closed, the controller 30 reduces the excitation of the solenoid coil 47 in response to the decrease of the pedal depression force, and finally cancels the excitation. Then, the movable iron core 38 moves forward by the output of the diaphragm piston 40, and moves from the valve portion 41 a of the valve body 41 to the vacuum valve seat 39.
c is released and the vacuum valve 50 is opened. For this reason, the working pressure chamber 23
Is introduced into the passage 24, the open vacuum valve 50, the hole 38d, the second vacuum chamber 24, and the passage hole 4 as described above.
4. The air is discharged to the negative pressure source 25 through the space 43, the passage hole 42, and the first vacuum chamber 22, and the negative pressure from the negative pressure source 25 is introduced into the working pressure chamber 23. Therefore, the power piston 1
2. Both the control piston 18 and the movable iron core 38 return to the inoperative position shown in the figure, and the brake is released.

When the negative pressure source 25 fails, the first and second
Atmospheric pressure is introduced into the vacuum chambers 22, 24 and the working pressure chamber 23, and no differential pressure is generated in the power piston 12. Therefore, when an input is given to the input rod 5 by depressing the brake pedal, an input from the input sensor 28 is input to the controller 30, and the controller 30 excites the solenoid coil 47 in response to the input, and 3
When the power piston 8 is actuated, the power piston 12 operates because no differential pressure is generated, and does not generate an output.

However, at this time, the input rod 5 directly presses the power piston 12 and the output rod 6 via the valve member 39 by the input based on the pedal depression force, so that the output rod 6 operates the MCY. Thereby, the negative pressure source 2
In the event of a failure, the brake can be operated reliably.

Incidentally, in the negative pressure booster 1 of this example,
In operation, the differential pressure between the operating pressure chamber 23 and the second vacuum chamber 24 regulates the stroke of the valve member 39 via the control piston 18 so that only the power piston 12 and the output rod 6 are stroked, Moreover, the valve member 39
Since the input rod 5 has almost no stroke as described above, the stroke of the input rod 5 is significantly smaller than the stroke of the conventional input rod for the same output of the vacuum booster 1, in other words, The pedal stroke is significantly reduced (for example, a stroke of 10 mm) as compared with a conventional pedal stroke (about 60 to 80 mm).
To about).

Thus, the pedal stroke is considerably smaller than the conventional pedal stroke even for the same pedal effort. Thus, in the negative pressure booster 1 of this example, as in the above-described example, FIGS.
As shown in FIG. 6, the characteristics of the pedaling force with respect to the pedal stroke, the characteristics of the deceleration with respect to the pedal stroke (ie, the output of the brake pressure or the negative pressure booster 1), and the deceleration with respect to the pedaling force (ie, the brake pressure or the negative pressure) Characteristic of the booster 1) can be obtained. Other functions and effects of the negative pressure booster 1 of this example are the same as those of the negative pressure booster 1 of each of the above-described examples.

FIG. 7 is a diagram partially showing another example of the embodiment of the present invention. The same components as those in the above-described example are denoted by the same reference numerals, and a detailed description thereof will be omitted.

As shown in FIG. 7, the negative pressure booster 1 of this embodiment is the same as the negative pressure booster 1 of the above-described embodiment.
A stroke setting means 51 is interposed between the input rod 9 and the input rod 5. The stroke setting means 51 includes a cylindrical nut member 52 screwed to the outer periphery of the rear end of the valve member 39.
The cylindrical nut member 52 is provided with the input rod 5.
Is penetrated to be relatively movable. A flange 53 is formed on the inner peripheral portion of the rear end of the cylindrical nut member 52,
The flange 54 of the input rod 5 and the flange 53 of the cylindrical nut member 52 are engaged with each other in a retreating direction (left direction in FIG. 6) of the input rod 5. Accordingly, the input rod 5 can move relative to the valve member 39 between a forward limit position where the flange 54 contacts the rear end of the valve member 39 and a retreat limit position where the flange 54 engages with the flange 53. ing. And the valve member 3
A spring 55 is contracted between the input rod 5 and the input rod 5, and the input rod 5 is constantly urged rearward with respect to the valve member 39 by the spring force of the spring 55, and the negative pressure is multiplied. When the force device 1 is not operated, the flange 54 is at the retreat limit position where the flange 54 is engaged with the flange 53. A stroke for controlling the stroke of the input rod 5 by the valve member 39, the input rod 5 movable relative to the valve member 39, and the spring 55 contracted between the valve member 39 and the input rod 5. The setting means 51 is configured. Other configurations of the vacuum booster 1 of this example are the same as those of the vacuum booster 1 of the above-described example.

When the brake pedal is depressed for brake operation, an input based on the pedal depression force is applied to the input rod 5, and the input rod 5 strokes forward while bending the spring 55, and pushes the valve member 39. After that,
The operation of the vacuum booster 1 of this example operates the brake in the same manner as in the above-described example.

As described above, since the spring 55 of the stroke setting means 51 interposed between the input rod 5 and the valve member 39 during operation is reduced by the input of the input rod 5, the input rod 5 is connected to the valve member 39. As a result, an extra stroke is caused by the reduction of the spring 55. That is, the stroke of the input rod 5, that is, the pedal stroke of the brake pedal changes according to the preset spring constant of the spring 55. Therefore, the spring 5 in the stroke setting means 51
By arbitrarily setting the spring constant of 5, the pedal stroke can be set freely.

Since the pedal stroke is determined by the spring constant of the spring 55 as described above,
It has nothing to do with the brake system (not shown) from MCY. That is, for example, even if the piston stroke of the MCY increases, the increase in the piston stroke simply increases the stroke of the power piston 19 of the vacuum booster 1 and simply increases the amount of air introduced into the working pressure chamber 30. Only the pedal stroke does not increase.

Although the stroke of the input rod 5 is larger than that of the valve member 39 by the contraction of the spring 55,
Since the amount of the increase is much smaller than the greatly shortened amount of the stroke of the valve member 39, the stroke of the input rod 5 is totally smaller than the stroke of the input rod 5 of the conventional vacuum booster 1. Greatly reduced.

Thus, the negative pressure booster 1 of this example is
The input rod 5 only strokes the stroke amount necessary to switch the control valve 41, and the stroke control means 33 allows the pedal stroke to be set freely regardless of the brake system from MCY. Thus, the negative pressure booster 1 has a very short stroke that hardly makes a stroke during operation. Negative pressure booster 1 of this example
Other functions and effects are the same as those of the negative pressure booster 1 of the above-described example.

In the present invention, the controller 30 excites the solenoid coil 47 and moves the movable iron core 38 to open the atmosphere valve 49 and supply the atmosphere to the working pressure chamber of the negative pressure booster. Accordingly, the negative pressure booster is operated, so that not only the input signal from the input sensor 28 but also the automatic brake can be applied as in the above-described example.

In each of the above-described embodiments, the fluid pressure booster is a negative pressure booster or a hydraulic pressure booster. However, the present invention is not limited to this. A fluid pressure booster including a power device, at least an operating piston such as a power piston that outputs an operation by the action of a fluid pressure, control means for supplying and controlling the fluid pressure, and input means for operating the control means. Any device can be applied to any fluid pressure booster.

Further, the fluid pressure booster of the present invention can be applied to any system other than the brake system, as long as the system requires a large output obtained by boosting the input.

Further, in the present invention, the controller 30 controls the operation of the electromagnetic proportional valve 26 to supply the fluid pressure to the working pressure chamber of the fluid pressure booster, thereby operating the fluid pressure booster. Therefore, not only the input signal from the input sensor 28 but also, for example, an input signal necessary for the operation of the automatic brake is input to the controller 30 and the controller 3
By controlling the operation of the electromagnetic proportional valve 26, the brake can be automatically applied regardless of the brake operation by depressing the pedal. That is, the brake system of the present invention can also be applied to automatic braking in inter-vehicle distance control, constant-speed running, stop holding, and the like. And
As described above, when the present invention is applied to the automatic brake, the brake pedal does not stroke when the automatic brake is activated, so that the driver does not feel uncomfortable and can maintain a good pedal feeling even when the automatic brake is activated.

[0103]

As is apparent from the above description, according to the fluid booster of the present invention, the stroke of the input means can be set to an extremely short stroke of almost zero. Moreover, even if the stroke of the input means is set to a very short stroke, the working piston can continue the stroke, so that a large output can be generated by boosting the input of the input means.

Also, when the fluid pressure fails, the operating piston is operated by the stroke of the input means. Therefore, even when the fluid pressure fails, the input to the fluid pressure booster is not boosted, but the output is surely increased. Can be done. In addition, since the working piston and the control means need only be disposed facing each other, the structure can be extremely simplified. Further, the stroke of the input means can be freely set by the stroke setting means.

Further, according to the brake system of the present invention, the stroke of a brake operating member such as a brake pedal can be set to a very short stroke. Thus, the brake operation is facilitated, and even when a strong brake operation force is required, such as during emergency braking, the stroke position of the brake operation member hardly changes, so that a large brake force can be generated.

In particular, when the brake is operated in a low G range such as a gentle brake or the like, the idle stroke which is indispensable to the brake system such as the working piston of the hydraulic booster, the master cylinder and the brake cylinder is sufficiently secured, and the brake is applied. The stroke of the operation member can be easily reduced.

In addition, the stroke of the brake operating member can be freely set irrespective of the brake system preceding the master cylinder which is operated by the output of the fluid pressure booster and generates the brake pressure.

Further, by supplying an input for automatic braking operation to the central processing unit, it becomes possible to operate automatic braking in inter-vehicle distance control, constant-speed running, stop holding, and the like. Moreover, when the automatic brake is operated in this way, the brake operation member does not stroke when the automatic brake is operated, so that the driver does not feel uncomfortable and can maintain a good pedal feeling even when the automatic brake is operated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a negative pressure booster as an example of an embodiment of a fluid pressure booster according to the present invention.

FIG. 2 is a diagram partially showing the hydraulic booster system shown in FIG. 1;

FIG. 3 is a diagram showing characteristics of the fluid pressure boosting system shown in FIG.

FIG. 4 is a view similar to FIG. 2, showing another example of the embodiment of the present invention.

FIG. 5 is a diagram showing a hydraulic booster system using a hydraulic booster as still another example of the embodiment of the present invention.

FIG. 6 is a view showing a fluid pressure boosting system using a negative pressure booster, showing still another example of the embodiment of the present invention.

FIG. 7 is a view showing a fluid pressure boosting system using a negative pressure booster, showing still another example of the embodiment of the present invention.

FIG. 8 is a sectional view similar to FIG. 1, showing a conventional vacuum booster.

[Explanation of symbols]

1: Negative pressure booster, 2: first shell, 3: second shell,
4: 3rd shell, 5: input piston, 6: output rod,
12 ... power piston, 18 ... control piston, 19 ... return spring, 20 ... control return spring,
Reference numeral 22: first vacuum chamber, 23: operating pressure chamber, 24: second vacuum chamber, 25: negative pressure source, 26: electromagnetic proportional valve, 28: input sensor, 29: pressure sensor, 29 ': hydraulic pressure sensor, 30 ... Central processing unit (controller), 31 ... Hydraulic booster, 3
2 ... housing, 33 ... cylindrical member, 34 ... pump, 35
... Motor, 36 ... Reservoir, 37 ... Accumulator, 3
8: movable iron core, 39: valve member, 40: diaphragm piston, 47: solenoid coil, 49: atmosphere valve, 5
0: vacuum valve, 51: stroke setting means

[Procedure amendment]

[Submission date] January 4, 2000 (200.1.4)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

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[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

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FIG. 4

[Procedure amendment 4]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

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FIG. 5

[Procedure amendment 5]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

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FIG. 6

[Procedure amendment 6]

[Document name to be amended] Drawing

[Correction target item name] Fig. 7

[Correction method] Change

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FIG. 7

[Procedure amendment 7]

[Document name to be amended] Drawing

[Correction target item name] Fig. 8

[Correction method] Change

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FIG. 8

Claims (7)

[Claims] 1. An operating piston for outputting an operation at an operating pressure of an operating fluid pressure, an electromagnetic control valve for controlling supply / discharge of an operating pressure applied to the operating piston and pressure control of an operating pressure, and an input during operation is provided. Input means for applying an input to the working piston in the event of a fluid pressure failure, stroke control means for operating with the working pressure acting on the working piston during operation to suppress the stroke of the input means, and the input means Input detection means for detecting an input given to the
A pressure detecting means for detecting the operating pressure, and a center for controlling the operating pressure by controlling the operation of the electromagnetic control valve based on the input detected by the input detecting means and the operating pressure detected by the pressure detecting means. A fluid pressure booster comprising a processing device. 2. An operating piston that outputs an operation at an operating pressure of an operating fluid pressure, an electromagnetic control valve that controls supply / discharge of an operating pressure applied to the operating piston and pressure control of the operating pressure, and an input during operation is provided. Input means for applying an input to the working piston in the event of a fluid pressure failure, stroke control means for operating with the working pressure acting on the working piston during operation to suppress the stroke of the input means, and the input means Input detection means for detecting an input given to the
A pressure detecting means for detecting the operating pressure, and a center for controlling the operating pressure by controlling the operation of the electromagnetic control valve based on the input detected by the input detecting means and the operating pressure detected by the pressure detecting means. The fluid pressure booster according to claim 1, further comprising a processing device, wherein the electromagnetic control valve comprises an electromagnetic proportional valve or an electromagnetic on-off valve. 3. The booster according to claim 1, wherein the booster is a negative pressure booster that boosts the input by using a negative pressure or a hydraulic booster that boosts the input by using a hydraulic pressure. Fluid pressure booster. 4. An operating piston that outputs an operation at an operating pressure generated by introducing the atmosphere during operation, an electromagnetic control valve that controls the supply and exhaust of the atmosphere acting on the operating piston, an input during operation, and Input means for applying an input to the working piston in the event of a pressure failure; a stroke control piston which operates with a working pressure acting on the working piston during operation to suppress the stroke of the input means; and detects an input of the input means. An input detection unit, a pressure detection unit for detecting an operating pressure acting on the operation piston, and a central processing unit to which the input detection unit, the pressure detection unit, and a solenoid of an electromagnetic control valve are connected. The operation of the valve is controlled by the input means, and the output of the control piston is acted on against the input from the input means. A valve member provided in series with the tongue and in contact with the operating piston, a moving member provided to be relatively movable with the valve member, a solenoid for driving the moving member, and a valve member and a moving member. A valve member provided so as to be relatively movable with respect to the member, wherein the valve member is provided with an atmospheric valve seat, the moving member is provided with a vacuum valve seat, and the valve member is further provided with these atmospheric valve seats. And a valve portion that can be attached to and detached from the vacuum valve seat, wherein the central processing unit operates the solenoid based on an input of the input means from the input detection means and an operating pressure from the pressure detection means during operation. A fluid pressure booster characterized by controlling. 5. A stroke setting means which can arbitrarily set a stroke of the input means is provided between the valve member and the input means.
5. The fluid pressure booster according to any one of items 4 to 4. 6. The electromagnetic control valve based on the operating pressure and the input so that an operating pressure acting on the operating piston at the time of operation becomes a pressure corresponding to an input of the input means. 2. The method according to claim 1, wherein
6. The fluid pressure booster according to any one of items 5 to 5. 7. A hydraulic pressure booster according to any one of claims 1 to 6, and at least a brake master cylinder which is activated by an output of the hydraulic pressure booster and generates a brake pressure. A brake system characterized by the following.