JP2001294145A - Hydraulic booster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact and inexpensive hydraulic booster capable of changing variously a stroke characteristic in an input side without affected by an output side, without requiring any modification of a large scale. SOLUTION: An input shaft 4 is advanced, a lever 27 is turned and a control valve 8 is operated, in an operation, and the control valve 8 generates hydraulic fluid pressure in respose to an input. The hydraulic fluid pressure is introduced into a power chamber 6, and a primary piston 37 is actuated by the fluid pressure to generate master cylinder pressure. On the other hand, the fluid pressure of the power chamber 6 is introduced into the first annular groove 25 of a valve spool 10, and the valve spool 10 receives action force to a right direction by a pressure receiving area difference for the fluid pressure in the annular groove 25. A function of a stroke simulator is exhibited by operation-controlling the valve spool 10 to balance the action force and spring force of a spring 32 with the input in a condition where a position of a turning fulcrum of the lever 27 is constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic booster which boosts the operating force of an operating means to a predetermined magnitude by a hydraulic pressure controlled by a control valve operated by an input shaft and outputs the boosted power. It belongs to the technical field, and particularly to the technical field of a hydraulic booster that can set various input strokes without being affected by the operation of an actuator such as a master cylinder operated by the output of the hydraulic booster. It is.

[0002]

2. Description of the Related Art For example, in a brake system of an automobile, a brake hydraulic booster for generating a large brake hydraulic pressure by boosting a pedal pressure of a brake pedal to a predetermined magnitude by a hydraulic pressure is conventionally used. ing. This brake hydraulic booster can obtain a large braking force with a small brake pedal depression force, thereby ensuring braking and reducing the driver's labor.

As one example of such a brake hydraulic pressure booster, a lever is rotated by an input based on the pedaling force of a brake pedal, and a control valve is operated by the rotation of the lever to operate the hydraulic pressure in accordance with the input. There is a lever type brake hydraulic pressure booster that boosts an input and outputs the hydraulic fluid by introducing the hydraulic pressure into a power chamber. Then, by operating the piston of the brake master cylinder with the output of the brake hydraulic pressure booster, the master cylinder generates a master cylinder pressure, and the master cylinder pressure is introduced to the wheel cylinder as the brake hydraulic pressure. The brake is activated.

[0004]

By the way, in the conventional brake system, for example, when an anti-lock control (ABS), a traction control (TRC), a brake assist control used for starting a slope, etc., and a regenerative brake are used together. Various brake controls such as regenerative brake control are performed.

[0005] Such brake control is often performed in a brake circuit from the master cylinder to the wheel cylinder. However, when the brake control is performed in the brake circuit before the master cylinder, a hydraulic booster is used. Is required not to be affected by the brake control because of, for example, a brake feeling.

[0006] However, in the brake system in which the conventional brake hydraulic pressure booster and the brake master cylinder are combined, such as the lever type brake hydraulic booster described above, the master cylinder and the wheel cylinder have a relationship between the master cylinder and the wheel cylinder. The stroke of the cylinder piston is determined, and the stroke of the master cylinder piston determines the stroke of the input shaft of the brake hydraulic booster, that is, the pedal stroke of the brake pedal. For this reason, the stroke on the input side is affected by the brake control in the brake circuit ahead of the master cylinder, and the combination of the conventional brake hydraulic booster and the brake master cylinder reliably and sufficiently satisfies the aforementioned requirements. It was difficult to respond.

Further, when the stroke characteristics of the brake pedal on the input side are changed due to a brake feeling or the like, the brake master cylinder and the brake circuit ahead of the brake master cylinder are also affected. These outputs need to be changed. In addition, when the output side is changed, the output characteristics of the brake are affected, so that the entire brake system needs to be reviewed and changed, and the scale of the change becomes large. Furthermore, even if the brake circuit before the master cylinder changes in various ways depending on the type and size of the vehicle, it is desired that the input side be as little affected by such different brake circuits as possible. Therefore, if the input side and the output side are simply separated to generate an output irrespective of the input stroke, the stroke on the input side stops, and the stroke on the input side cannot be secured.

Therefore, conventionally, a stroke simulator is provided in the brake circuit before the master cylinder so that the input stroke of the brake hydraulic booster is not affected by the brake control before the master cylinder. In addition, it has been proposed to secure an input stroke. However, the special provision of the stroke simulator requires many components such as a stroke cylinder and an electromagnetic on-off valve used in the stroke simulator, which not only complicates the configuration but also increases the cost. Will be. Further, even when a stroke simulator or the like is provided, there is a problem that it is necessary to ensure that the brake operation can be performed when the hydraulic pressure source fails.

The present invention has been made in view of such circumstances, and has as its object to variously change the stroke characteristics on the input side without requiring a large-scale change without being affected by the output side. It is to provide a compact and inexpensive hydraulic booster capable of doing so.

[0010]

In order to solve the above-mentioned problems, a hydraulic booster according to the present invention has an input member that strokes with an input applied during operation, and an operation controlled by the input member. A control valve that controls the hydraulic pressure of the hydraulic pressure source in accordance with the amount of operation of the input member to generate a hydraulic pressure for operating the actuator. As well as acting on
Disposing an elastic member between the control valve and the input member,
The operating force of the elastic member according to the operation amount of the input member acts on the control valve in the operating direction, and the control valve operates the operating force of the hydraulic fluid and the operating force of the elastic member. The operation is controlled in accordance with the operation amount so as to balance with the operation amount.

According to a second aspect of the present invention, the control valve comprises a spool valve, and the spool valve is configured such that the operating force of the elastic member is applied in the operation direction and the hydraulic fluid pressure is applied in the non-operation direction. The valve spool has a valve spool that is controlled by the input member so that the acting force of the hydraulic fluid acting on the valve spool and the acting force of the elastic member are balanced. The operation is controlled according to the input. Further, in the invention according to claim 3, the control valve comprises a spool valve, and in the spool valve, the operating force of the elastic member is applied in an operating direction and the operating hydraulic pressure is applied in a non-operating direction. The valve spool responds to an input from the input member such that the acting force of the hydraulic fluid acting on the valve spool and the acting force of the elastic member are balanced. It is characterized in that the operation is controlled.

Further, according to a fourth aspect of the present invention, the control valve comprises a ball valve or a conical valve, and the ball valve or the conical valve acts on the operating force of the elastic member in the operating direction and reduces the operating hydraulic pressure. Actuated in the non-acting direction, and actuated in response to an input from the input member so that the acting force of the working fluid pressure and the acting force of the elastic member are balanced. I have.

Further, the invention according to claim 5 is characterized in that the elastic member is provided coaxially with the input member, and the control valve is provided at a predetermined interval in the input section. A lever, which is actuated by an operation force of the elastic member in accordance with an operation amount of the input member and acts on the control valve in an operating direction, between the control valve and the control valve; Is constant irrespective of the stroke of the input member, and the control valve is actuated in response to an input from the input member such that the acting force due to the hydraulic pressure and the acting force due to the rotation of the lever are balanced. It is characterized by being controlled.

Further, according to a sixth aspect of the present invention, the input member is slidable with respect to the lever, and a sliding lubrication member is provided at a sliding portion between the input member and the lever. It is characterized by being. Further, the invention of claim 7 is characterized in that the sliding lubricating member is a bush or a linear bearing. Further, the invention according to claim 8 is characterized in that a pivot point of the lever is arranged on one of the input member side and the control valve side. Further, the invention according to claim 9 is characterized in that the elastic member comprises a plurality of springs or non-linear springs.

[0015]

In the hydraulic booster of the present invention having the above-described structure, the elastic member generates an operating force corresponding to the operation amount of the input member by the input applied to the input member, and the operating force of the elastic member is increased. Acts on the control valve in the operating direction to operate the control valve, and the operation of the control valve controls the hydraulic pressure of the hydraulic pressure source to control the hydraulic pressure according to the operation amount of the input member.
The hydraulic pressure controlled by the control valve is generated as an output, and the actuator is directly operated by the output hydraulic pressure. At the same time, the hydraulic pressure acts on the control valve in a non-operational direction. At this time, the operation of the control valve is controlled according to the operation amount of the input member so that the operation force by the hydraulic fluid and the operation force by the elastic member are balanced.

When the hydraulic pressure source operates in a normal state, the position of the control valve is constant irrespective of the stroke of the input member, and the hydraulic booster operates such that the input side and the output side are separated. become. Even if the input side and the output side are separated in this way, the operation of the control valve is controlled according to the operation amount of the input member so that the operation force by the hydraulic fluid and the operation force by the elastic member are balanced. Thus, the function as a stroke simulator is exhibited.

As described above, in the hydraulic booster of the present invention, even if the input side and the output side operate separately, the hydraulic booster exhibits the function of the stroke simulator. The input stroke is ensured, and the input stroke of the input member can be variously set without being affected by the control situation on the output side prior to the actuator. Further, since the control valve and the lever of the conventional hydraulic booster can be used for the control valve and the lever of the present invention with almost no change, the hydraulic booster of the present invention uses special parts. Instead, it is simple and inexpensive.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a brake hydraulic booster to which a first embodiment of a hydraulic booster according to the present invention is applied, and FIG. 2 is control of the brake hydraulic booster shown in FIG. FIG. 3 is a partially enlarged cross-sectional view of the master cylinder portion shown in FIG. 1. In the following description, the up, down, left, and right directions represent the up, down, left, and right directions in the drawings, respectively, and the front and rear directions respectively correspond to the left and right in the drawings.

As shown in FIG. 1, in the brake hydraulic booster 1 of the first embodiment, a master cylinder is integrally connected, and the master cylinder is operated by the output of the brake hydraulic booster 1. It has become. As shown in FIGS. 1 and 2, the brake hydraulic booster 1 has a housing 2 for a brake hydraulic booster. The input piston 3 is tightly and slidably fitted, and is connected to a brake pedal (not shown).
An input shaft 4 (corresponding to an input member of the present invention) is connected to the input piston 3. A power piston 5 is provided in the brake hydraulic booster housing 2 coaxially with the input shaft 4 in a fluid-tight manner. The power piston 5 defines a power chamber 6 in front of the power piston 5. I have. As described above, the power piston 5 functions as a plug that defines the power chamber 6 in the brake hydraulic booster 1 of this example, and does not perform the function of generating the output of the brake hydraulic booster 1. Lever support 5a at the rear end of the power piston 5
The first and second steps 2 (described later) of the housing 2
a, 2b, and is fixed to the second step portion 2b by a spring 7 contracted in the power chamber 6.
Further, a front end 4 a of the input shaft 4 penetrates the power piston 5 in a liquid-tight and slidable manner, and faces the power chamber 6.

Further, a control valve 8 is provided in the housing 2 in parallel with the input shaft 4 at a predetermined interval.
The control valve 8 is constituted by a spool valve composed of a valve sleeve 9 fitted and fixed in a liquid-tight manner in the housing 2 and a valve spool 10 slidably fitted in the valve sleeve 9. . The cylinder hole in the axial direction of the valve sleeve 9 is provided with a step 9a, and is formed as a stepped hole including a small-diameter cylinder hole 9b at the front end and a large-diameter cylinder hole 9c at the rear end from the center. The first to fifth radial holes 1 are provided in the valve sleeve 9 from the front end side.
1, 12, 13, 14, and 15 are provided respectively. In this case, the first radial hole 11 is formed in the small-diameter cylinder hole 9b, and the second to fifth radial holes 12, 13,.
Both 14 and 15 are formed in the large-diameter cylinder hole 9c.

The first radial hole 11 is always connected to a reservoir for a brake hydraulic booster (not shown) through passage holes 16, 17, 18 of the housing 2, and therefore, is located in front of the valve spool 10. A space 19 in the valve sleeve 9 is always in communication with the reservoir. Second
The radial holes 12 are formed in the passage holes 20, 21, 22 of the housing 2.
And the third radial hole 13 is always connected to the reservoir for the brake hydraulic booster through the passage hole 18. Further, the fourth radial hole 14 is provided with the passage hole 23 of the housing 2 and the hydraulic pressure inlet 2.
The hydraulic pressure stored in the accumulator is constantly introduced by a pump (not shown) of the hydraulic pressure source, which is always connected to the accumulator of the hydraulic pressure source (not shown) through 4.
Further, the fifth radial hole 15 is provided with a passage hole 22 of the housing 2.
, And is always connected to the power room 6.

The valve pool 10 is formed as a step having a small-diameter spool portion 10a at the front end and a large-diameter spool portion 10b at the rear end from the center. In this case, the small-diameter spool portion 10a is fitted in the small-diameter cylinder hole 9b of the valve sleeve 9 in a liquid-tight and slidable manner, and the large-diameter spool portion 10b is
c so as to be slidable. This valve spool 1
0, the small-diameter spool portion 10a and the large-diameter spool portion 10b
And a second annular groove 26 is formed in the large-diameter spool portion 10b.

The first annular groove 25 is always connected to the second radial hole 12, and is connected to the third radial hole 13 when the illustrated valve spool 10 is not operated, so that the power chamber 6 is multiplied by the brake hydraulic pressure. The hydraulic pressure in the power chamber 6 is set to the atmospheric pressure, and the power chamber 6 is disconnected from the third radial hole 13 when the valve spool 10 is operated forward, so that the power chamber 6 is connected to the brake hydraulic pressure booster. From the reservoir. The third radial hole 13 and the first annular groove 25 constitute a hydraulic pressure discharge valve. On the other hand, the second annular groove 26 is always connected to the fifth radial hole 15, and is shut off from the fourth radial hole 14 when the valve spool 10 is not operated to shut off the power chamber 6 from the accumulator of the hydraulic pressure source. In addition, when the valve spool 10 is moved forward, the power chamber 6 is connected to the fourth radial hole 14 to connect the power chamber 6 to the accumulator, and the hydraulic pressure of the accumulator is introduced into the power chamber 6. The fourth radial hole 14 and the second annular groove 26 constitute a hydraulic pressure supply valve.

When the hydraulic pressure discharge valve is closed and the hydraulic pressure supply valve is opened to introduce hydraulic pressure into the power chamber 6, the hydraulic pressure in the power chamber 6 is also introduced into the first annular groove 25, When the hydraulic pressure of the first annular groove 25 acts on the small-diameter and large-diameter spool portions 10a and 10b having different pressure receiving areas, the valve spool 10 is biased rightward, that is, toward the non-operation position. I have. Further, the lever support portion 5 of the power piston 5
At a, one end of a lever 27 is swingably supported by a first support pin 28. The other end of the lever 27 is swingably supported by a valve operating member 29 by a second support pin 30.

A retainer portion 62 is slidably fitted to the input shaft 4, and a return spring 31 (corresponding to an elastic member of the present invention) is provided between the retainer portion 62 and the input piston 3. The return spring 31 constantly biases the input piston 3 and the input shaft 4 rearward with respect to the retainer portion 62. When the illustrated input shaft 3 is not operated, the flange portion 4b of the input shaft 4 contacts the retainer portion 62, and the retreat limit of the input shaft 4 is defined. Also, retainer 6
2 is provided with an elongated hole 62a in the vertical direction. An engaging pin 27a projecting inward from the lever 27 can be engaged with the elongated hole 62a in the front-rear direction (left-right direction in the figure). And slidably in the vertical direction. First
The distance between the support pin 28 and the engagement pin 27a is always smaller than the distance between the engagement pin 27a and the second support pin 30 regardless of whether the brake hydraulic booster 1 is operated or not. It is set to be.

The valve operating member 29 is fitted and fixed to the valve spool 10. The valve operating member 29 is constantly urged rearward by a spool return spring 32.
When not operating, the valve operating member 29 and the valve spool 10
Is set to a non-operating position where the rear end of the illustrated valve spool 10 is in contact with the housing 2.

Next, the master cylinder will be described. As shown in FIGS.
Is provided with a cylindrical master cylinder housing 34 having a rear end opening, and a sleeve 35 is disposed inside the master cylinder housing 34,
A cylindrical cap 36 that axially supports the sleeve 35 between the sleeve 35 and the master cylinder housing 34 is screwed to the master cylinder housing 34 in a liquid-tight manner. The cap 36 is liquid-tightly fitted and fixed to the brake hydraulic booster housing 2. The master cylinder 33 is configured as a tandem master cylinder having a primary piston 37 and a secondary piston 38 whose effective pressure receiving areas are set equal to each other.

The primary piston 37 is disposed in the power chamber 6 in the brake hydraulic booster housing 2 and in each hole of the cap 36 and the sleeve 35. The primary piston 37 includes a first cup seal 39 provided on the inner peripheral surface of the hole of the cap 36, and a sleeve 35.
And a second cup seal 40 provided on the inner peripheral surface of the hole of the cap 36 in a liquid-tight and slidable manner. Second cup seal 40
Is designed to block the flow of liquid from the front side to the rear side and allow the reverse flow. Further, the primary piston 37 is supported by the hydraulic booster housing 2 so as to be slidable in a liquid-tight manner by a third cup seal 41, and the rear end 37 a of the primary piston 37 is connected to the power chamber 6.
Faces.

The secondary piston 38 is disposed in a hole of the sleeve 35 and in the master cylinder housing 34. The secondary piston 38 has a sleeve 35
A fourth cup seal 42 provided on the inner peripheral surface of the hole of the first cylinder and a fifth cup provided on the inner peripheral surface of the hole of the master cylinder housing 34 and disposed between the master cylinder housing 34 and the sleeve 35. The seal 43 is provided so as to be liquid-tight and slidable. Fifth cup seal 43
Is designed to block the flow of liquid from the front side to the rear side and to allow the flow of liquid in the opposite direction.

A primary chamber 44 is formed between the primary piston 37 and the secondary piston 38, and a primary return spring 46 whose maximum length is regulated by a primary spring retainer 45.
Has been curtailed. A secondary chamber 47 is formed in a hole between the master cylinder housing 34 and the secondary piston 38, and a secondary return spring 49 whose maximum length is regulated by a secondary spring retainer 48 is contracted. . In that case, the spring force of the secondary return spring 49 is set to be larger than the spring force of the primary return spring 46.

The primary piston 37 has a radial hole 50
Are drilled. The radial hole 50 is located slightly behind the cup seal 40 in the illustrated inoperative position of the primary piston 37, and at this time, the primary chamber 44 defines the radial hole 50, the rear surface of the cup seal 40, and the cap. 36, an axial hole 36a formed in the cap 36, and a cap 3 between the cup seals 39 and 40.
6 is connected to the master cylinder reservoir 51 via a circumferential groove 36b drilled in the groove 6, an inclined hole 36c extending continuously from the circumferential groove 36b in the axial direction, and a radial hole 34a of the master cylinder housing 34. It has become.

Therefore, in this state, no master cylinder pressure is generated in the primary chamber 44. In addition, the radial hole 50 is formed in the cup seal 4 by the advance of the primary piston 37.
When it is located forward of 0, the flow of liquid from the primary chamber 44 to the reservoir 51 is shut off, so that a master cylinder pressure is generated in the primary chamber 44.

The secondary piston 38 has a radial hole 52.
Are drilled. The radial hole 52 is located slightly behind the cup seal 43 when the secondary piston 38 is in the non-operating position shown in the figure, and at this time, the secondary chamber 47 is in contact with the radial hole 52 and the inner peripheral surface of the sleeve 35. It is connected to the master cylinder reservoir 51 via a gap between the secondary piston 38, a radial hole 35a formed in the sleeve 35, and a radial hole 34b of the master cylinder housing 34.

Therefore, in this state, no master cylinder pressure is generated in the secondary chamber 47. Further, when the secondary piston 38 advances, the radial hole 52 is formed in the cup seal 4.
When it is located forward of 3, the flow of liquid from the secondary chamber 47 to the reservoir 51 is interrupted, so that a master cylinder pressure is generated in the secondary chamber 47.

The primary chamber 44 is connected to a wheel cylinder of one of the two brake systems via a hole 53 formed in the sleeve 35 and a primary output port 54 formed in the housing 34 for the master cylinder. The secondary chamber 47 is connected to a wheel cylinder (not shown) of the other of the two brake systems via a secondary output port 55 formed in the master cylinder housing 34. The chamber 56 in the housing 2 of the brake hydraulic booster 1 in which the lever 27 and the like are accommodated is always connected to the brake hydraulic booster reservoir through the passage hole 57 and the passage hole 18. It is always kept at atmospheric pressure.

In the brake hydraulic booster 1 of the first example thus configured, when the brake is not operated, the input piston 3 and the input shaft 4 are at the retreat limit positions shown in FIGS. Since the lever 27 is also at the non-operation position, the control valve 8 is in the non-operation state described above, and the hydraulic pressure supply valve is closed and the hydraulic pressure discharge valve is open. Therefore, since the power chamber 6 is shut off from the accumulator and communicates with the reservoir for the brake hydraulic pressure booster,
The hydraulic pressure from the accumulator is not supplied into the power chamber 6.

Also, the master cylinder 33 does not operate,
As shown in FIG.
0 is behind the second cup seal 40, and the primary chamber 44 has the radial hole 50, the axial hole 36a, and the circumferential groove 36.
b, the inclined hole 36c, and the radial hole 34a of the housing 34 communicate with the master cylinder reservoir 51.
Further, the radial hole 52 of the secondary piston 38 is located behind the fifth cup seal 43, and the secondary chamber 47 communicates with the reservoir 10 through the radial hole 52 and the two radial passage holes 35a and 34b. Therefore, no master cylinder pressure is generated in the primary chamber 44 and the secondary chamber 47.

When the brake is operated, an input based on the pedal depression force is applied to the input piston 3 and the input shaft 4 by depressing the brake pedal, and the input piston 3 and the input shaft 4 move forward. At this time, the retainer portion 62 does not follow the forward movement of the input piston 3 and the input shaft 4 because the long hole 62a and the engaging pin 27a are engaged in the front-rear direction. Increase. The increased biasing force of the return spring 31 is transmitted to the lever 27 by the longitudinal engagement between the elongated hole 62a and the engagement pin 27a, and the lever 27 rotates counterclockwise about the first support pin 38. I do. By the counterclockwise rotation of the lever 27, the valve spool 10 advances through the valve operating member 29. Then, the first annular groove 25 becomes the third annular groove.
The hydraulic pressure discharge valve is closed by being shut off from the radial hole 13, and the second annular groove 26 is connected to the fourth radial hole 14 to open the hydraulic pressure supply valve, and the fluid from the accumulator is stored in the power chamber 6. Pressure is supplied.

The hydraulic pressure introduced into the power chamber 6 acts on the rear end face of the primary piston 37, and the primary piston 37 moves forward. The hydraulic pressure in the power chamber 6 is also introduced into the first annular groove 25 through the passage holes 21 and 20 and the second radial hole 12. Since the hydraulic pressure introduced into the first annular groove 25 acts on the small-diameter and large-diameter spool portions 10a and 10b having different pressure receiving areas as described above, the valve spool 10 closes the hydraulic pressure supply valve and the hydraulic pressure discharge valve. Is biased in the opening direction. Then, the valve force is adjusted so that the spring force of the litter spring 31, that is, the input applied to the input piston 3, and the spring force of the spool return spring 32 and the urging force of the valve spool 10 due to the hydraulic pressure of the first annular groove 25 are balanced. The spool 10 is controlled. By controlling the balance of the valve spool 10 in this manner, the hydraulic pressure in the power chamber 6 becomes a hydraulic pressure according to the input of the input shaft 4, that is, the pedaling force, and the brake hydraulic booster 1 enters the intermediate load state. . As a result, the output of the brake fluid pressure booster 1 becomes the magnitude of the input at this time, that is, the magnitude obtained by boosting the depression force of the brake pedal. That is, the hydraulic pressure of the power chamber 6, that is, the output of the brake hydraulic pressure booster 1 is controlled according to the stroke of the input shaft 4, that is, the pedal stroke. Further, the hydraulic pressure in the power chamber 6 also acts on the front end of the input shaft 4 in the backward direction, and is transmitted to the driver via the brake pedal as a reaction force.

The primary piston 37 advances and its radial hole 50 passes through the second cup seal 40, and a master cylinder pressure is generated in the primary chamber 44. Further, by the master cylinder pressure generated in the primary chamber 44 and the spring force of the primary return spring 46, the secondary piston 38 advances and its radial hole 52 passes through the fifth cup seal 43. Cylinder pressure occurs. Then, the master cylinder pressure generated in the primary chamber 44 is introduced into both wheel cylinders of one system via the primary output port 54, and the master cylinder pressure generated in the secondary chamber 47 is transmitted from the secondary output port 5 to the other wheel cylinder. Introduced to both wheel cylinders of the system, two systems of brakes operate. At this time, the master cylinder pressures of the primary chamber 44 and the secondary chamber 47 are the same, and the same hydraulic pressure is supplied to each of the two wheel cylinders, and the brake hydraulic pressures of the two systems are equal. Has become. This brake fluid pressure has a magnitude obtained by boosting the depression force of the brake pedal.

At this time, the primary piston 37 has a stroke corresponding to the amount of liquid consumed by the two brake systems, but the input shaft 4 balances the action force of the power chamber 6 acting on the valve spool 10 by the fluid pressure of the power chamber 6. Since the stroke of the return spring 31 and the force of the power chamber 6 acting on the input shaft 4 due to the hydraulic pressure acting on the input shaft 4 are balanced with the input from the brake pedal acting on the input shaft 4, the stroke is balanced.
The input shaft 4 and the primary piston 37 are separated. That is, the stroke of the input shaft 4 on the input side is
Regardless of the amount of liquid consumed by the two brake systems on the output side, the stroke corresponds to the input from the brake pedal.

When the brake pedal is released to release the brake operation, the input shaft 4 moves backward. Then, the spring force of the return spring 31 decreases, the lever 27 rotates clockwise about the first support pin 38, and the valve operating member 29 retreats. Thus, the second annular groove 26 is shut off from the fourth radial hole 14 to close the hydraulic pressure supply valve, and the first annular groove 25 is connected to the third radial hole 13 to open the hydraulic pressure discharge valve. Therefore, the hydraulic fluid in the power chamber 6 is discharged to the reservoir for the brake hydraulic booster through the hydraulic pressure discharge valve, and the hydraulic pressure in the power chamber 6 decreases.

When the fluid pressure in the power chamber 6 decreases, the primary piston 37 is actuated by the master cylinder pressure in the primary chamber 44 and the spring force of the primary return spring 46.
Retreats. With the retraction of the power piston 5, the lever 2
Reference numeral 7 rotates counterclockwise about the second support pin 30.
Further, since the master cylinder pressure in the primary chamber 44 decreases due to the retraction of the primary piston 37, the secondary piston 38 is reduced by the master cylinder pressure in the secondary chamber 47 and the spring force of the secondary return spring 49.
Also retreat. With the retraction of the primary piston 37 and the secondary piston 38, the radial hole 50 and the radial hole 52 are respectively connected to the second cup seal 40 and the fifth cup seal 40.
Since it passes through the cup seal 43 and is located again behind the second cup seal 40 and the fifth cup seal 43, both the primary chamber 44 and the secondary chamber 33 communicate with the master cylinder reservoir 10 again. For this reason, the hydraulic fluid of the wheel cylinders of both systems is discharged to the master cylinder reservoir 10 through the primary chamber 44 and the secondary chamber 47, respectively.

When the input of the input shaft 4 is extinguished and the hydraulic pressure in the power chamber 6 becomes the atmospheric pressure, the primary piston 37 is in the non-operation position, the secondary piston 38 is also in the non-operation position, and the master cylinder 33 is in the non-operation position. No master cylinder pressure is generated. Thereby, the brakes of both brake systems are quickly released.

When the brake is operated, the depression force of the brake pedal is greatly increased, and the valve operating member 29 of the control valve 8 and the valve spool 10 are largely advanced. When the hydraulic pressure supply valve is opened to the maximum, the hydraulic pressure of the power chamber 6 is reduced. The pressure becomes equal to the pressure of the accumulator and does not increase any more, and the brake hydraulic booster 1 is in the full load state. In such a full load state of the brake hydraulic pressure booster 1, since the hydraulic pressure in the power chamber 6 is constant, further movement of the primary piston 37 due to the hydraulic pressure in the power chamber 6 stops. However, even in this full load state, when the input shaft 4 moves forward, the lever 27 further rotates counterclockwise about the first support pin 38, and the valve operating member 29 and the valve spool 10 further move forward. . When the front end of the valve spool 10 comes into contact with the opposing wall of the housing 2, the valve spool 10 and the valve operating member 29 do not advance any further.

When the depressing force of the brake pedal further increases,
Only the input shaft 4 moves further. At this time, the stroke amount of the input shaft 4 is a small stroke amount in the above-described intermediate load state. When the input shaft 4 relatively moves by this stroke amount, the front end of the input shaft 4 comes into contact with the primary piston 37, and the primary piston 3
7 is pressed directly by the input shaft 4. Therefore, when the brake hydraulic pressure booster 1 is at full load, the master cylinder pressure increases by an increase in the input of the input shaft 4, that is, by an increase in the pedal depression force.

During operation, the hydraulic pressure introduced into the power chamber 6 also acts on the power piston 5.
The power piston 5 does not move while being in contact with the second step 2b of the housing 2. Therefore, the first support pin 28 is attached to the lever support portion 5a of the power piston 5.
The position of the rotation fulcrum of the lever 27, which is swingably supported, does not move and is kept constant regardless of the stroke of the input shaft 4.

If a hydraulic pressure source such as a pump or an accumulator fails and hydraulic pressure from the accumulator is not introduced into the power chamber during a brake operation, when the brake pedal is depressed and the input shaft 4 moves forward, all of the above-described operations are performed. As in the case of the load state, the front end of the input shaft 4 comes into contact with the primary piston 37, and the primary piston 37 is directly pressed by the input shaft 4. Therefore, since the primary piston 37 moves forward, even when the hydraulic pressure source fails, the master cylinder 33 generates the master cylinder pressure, and the brake of the two-brake system operates.

As described above, according to the brake hydraulic pressure generator 1 of the first example, the primary piston 37 of the master cylinder 3 is operated by the control valve 8 in response to the input of the input piston 3 when the hydraulic pressure source operates normally. Operating with the hydraulic fluid pressure controlled in a controlled manner, and with the position of the pivot point of the lever 27 kept constant, the spring force of the return spring 31, that is, the input applied to the input piston 3 and the spool return spring 32 By controlling the valve spool 10 so that the spring force and the urging force of the valve spool 10 due to the hydraulic pressure of the first annular groove 25 are balanced, the function of the stroke simulator is exerted. The input side and the output side of the device 1 can be separated, and the small diameter spool portion 10a of the valve spool 10 and the large diameter By setting the difference in pressure receiving area with the spool portion 10b and the spring force of the spool return spring 32 variously, the stroke characteristics on the input side can be variously changed without affecting the output side of the brake hydraulic booster 1. Will be able to

Further, the return spring 31, the spool return spring 32, and the small-diameter spool portion 10a and the large-diameter spool portion 10b of the valve spool 10, which exhibit the function of the stroke simulator, are simply incorporated in the brake hydraulic booster 1. Since a separately formed stroke simulator is not attached externally, the hydraulic booster 2
Can be formed compactly.

Further, since the conventional lever-type brake fluid pressure booster itself has the function of a stroke simulator, there is no need to provide a special stroke simulator specially. Force device 1
By simply changing the above, the conventional lever type brake hydraulic booster 1 can be simplified and the cost can be reduced.

FIG. 4 is a partial sectional view showing the input piston, the input shaft, and the lever 27 according to a second embodiment of the present invention. In the following description of each embodiment of the present invention, the same components are denoted by the same reference numerals. In the first example described above, only one return spring 31 contracted between the input piston 3 and the retainer 62 is used. However, in the brake hydraulic booster 1 of the second example, FIG. As shown in FIG.
First and second return springs 31a, 31b
Is used. In this case, in the second example, the first return spring 31a is constantly contracted between the input piston 3 and the retainer 62 as in the case of the return spring 31 of the first example. The maximum length of the second return spring 31b is regulated by a spring retainer 57, and is interposed between the input piston 3 and the retainer 62. This second return spring 31b is
Until the input piston 3 makes a predetermined stroke from the inoperative position, it does not contact at least one of the input piston 3 and the retainer 62. Other configurations of the brake hydraulic booster 1 of the second example and the master cylinder 33 are the same as those of the above-described first example.

In the brake hydraulic booster 1 of the second example having the above-described structure, when the input piston 3 moves forward during the braking operation, the return spring 31 of the first example is used.
As in the case of (1), the first return spring 31a bends to increase the urging force of the first return spring 31a, and the urging force causes the lever 27 to rotate counterclockwise to rotate the control valve 8
The hydraulic pressure discharge valve is closed, the hydraulic pressure supply valve is opened, and the hydraulic pressure from the accumulator is introduced into the power chamber 6, the master cylinder 33 generates the master cylinder pressure, and the two-system brake operates.

Since the second return spring 31b does not abut on at least one of the input piston 3 and the retainer 62 until the input piston 3 makes a predetermined stroke, only the first return spring 31a bends without bending. Therefore, at this time, the input piston 3 corresponding to the input of the input piston 3 corresponding to the pedal depression force
Is relatively large. When the input piston 3 strokes by a predetermined amount, the second return spring 31b
Are in contact with both the input piston 3 and the retainer 62, and the second return spring 31b also bends together with the first return spring 31a for the input of the input piston 3 thereafter. Therefore, thereafter, the stroke of the input piston 3 with respect to the input of the input piston 3 becomes relatively small, and the input stroke characteristic with respect to the input initially becomes a straight line having a relatively large inclination, and after the bending of the second return spring 31b starts. The slope becomes a relatively small straight line and has a two-stage characteristic consisting of a broken line.

On the other hand, in the brake hydraulic booster 1 of the second example, even if the input-input stroke characteristic becomes a two-stage characteristic, the hydraulic pressure-hydraulic characteristic of the power chamber 6 with respect to the input of the input piston 3 does not change. As in the case of the above-described first example, the characteristic has a single straight line having a predetermined inclination. This is because the spring force of the first and second retarder springs 31a and 31b is in accordance with the input applied to the input piston 3, and the spring force of the first and second retarder springs 31a and 31b and the spool return spring 32 By controlling the valve spool 10 so that the spring force of the valve spring 10 and the urging force of the valve spool 10 due to the hydraulic pressure of the first annular groove 25 are balanced, the hydraulic pressure of the power chamber 6 increases That is, the hydraulic pressure is controlled according to the pedaling force. Other functions and effects of the brake hydraulic booster 1 of the second example are the same as those of the first example.

FIG. 5 is a partial sectional view, similar to FIG. 2, showing a third embodiment of the present invention. In the above-described second example, the power piston 5 is fixed to the housing 2. However, in the brake hydraulic booster 1 of the third example, the power piston 5 is connected to the first and second step portions 2 of the housing 2.
It can be moved a predetermined distance between a and 2b. Also,
In the third example, as shown in FIG.
a does not penetrate the power piston 5 but is simply slidably fitted in the axial hole 5 a of the power piston 5 in a liquid-tight manner. A reaction force chamber 58 is formed by the front end 4 a of the input shaft 4 in an axial bottomed hole 5 a in front of the front end 4 a of the input shaft 4. It is always connected to the power chamber 6 through the radial hole 5b. Further, in the third example, the lever 27 is swingably supported by the housing 2 by the first support pin 28. Other configurations of the brake hydraulic booster 1 of the third example and the master cylinder 3 are the same as those of the second example.

The brake hydraulic booster 1 according to the third embodiment having the above-described structure operates as follows. When the brake is operated, the hydraulic pressure from the accumulator is introduced into the power chamber 6 as in the first and second examples described above, and the primary piston 37 advances, and the brake is operated. At this time, the hydraulic pressure in the power chamber 6 is introduced into the reaction force chamber 58 through the radial hole 5b, so that the hydraulic pressure in the reaction force chamber 58
a and is transmitted to the driver as a reaction force.

In general, the stroke of each piston 37, 38 of the master cylinder 3 changes according to the output side of the master cylinder 3, that is, the condition from the master cylinder 3 to the wheel cylinder. For example, in a regenerative cooperative brake system in which a hydraulic brake system using the brake hydraulic booster 1 of the present invention and a regenerative brake system are combined, when the regenerative brake is operated, the amount of the braking force by this regenerative brake is Although it is necessary to reduce the braking force of the brake system, in order to reduce the braking force in this manner, the master cylinder pressure must be reduced, and the pistons 37 and 38 are returned. In such a case, in the third example, even if the primary piston 37 is returned to the right, the front end 4
There is no direct contact with a, and the brake operation feeling is not impaired.

In a full load operation when the hydraulic pressure source is normal, the hydraulic pressure in the power chamber 6 does not rise above the set maximum hydraulic pressure.
In the third example, the input shaft 4 cannot contact the primary piston 37 even if the input shaft 4 further strokes due to the input rise in the full load operating state. Therefore, at the time of full load operation, the primary piston 37 does not advance even if the input increases, and the master cylinder pressure does not increase more than the hydraulic pressure of the power chamber 6 at the time of full load operation.

Further, when the hydraulic pressure source fails, the input shaft 4 moves forward greatly and comes into contact with the power piston 5, and the power piston 5 is further advanced and comes into contact with the primary piston 37. Therefore, at this time, the primary piston 37 is advanced through the power piston 5 by the advance of the input shaft 4, and the brake is operated in the same manner as in the first and second examples. Other functions and effects of the brake hydraulic booster 1 of the third example are the same as those of the second example.

FIG. 6 is a partial sectional view similar to FIG. 5, showing a fourth embodiment of the present invention. In the above-described third example, the reaction force chamber 58 is connected to the power chamber 6 through the radial hole 5b. However, in the brake hydraulic booster 1 of the fourth example, the radial hole 5b is deleted and the reaction force chamber 58 is removed. The power chamber 58 is isolated from the power chamber 6. The reaction force chamber 58 includes an axial hole 4 d and a radial hole 4 e formed in the front end 4 a of the input shaft 4.
It is connected to the pressure control valve 59 through an annular groove 5c and a radial hole 5d provided in the power piston 5 and an annular groove 2c and a radial hole 2d provided in the housing 2. When the pressure control valve 59 is not operated, the reaction force chamber 58 is connected to the reservoir for the brake hydraulic pressure booster. When the pressure control valve 59 is operated, the pressure of the accumulator of the hydraulic pressure source is controlled to a predetermined pressure and the reaction force chamber 58 is controlled. 58.
The hydraulic pressure introduced into the reaction force chamber 58 acts on the input shaft 4 to generate a reaction force.

Further, in the brake hydraulic booster 1 of the fourth embodiment, the structure of the control valve 8 is different from that of each of the above embodiments.
That is, the first and second radial directions 11 and 12 of the valve sleeve 9 and the passage holes 16, 17, 20, 21 and 57 of the housing 2 in each of the above-described examples are omitted in the fourth example. The fourth example of the valve sleeve 9 in each of the above-described examples.
The radial direction 14 is provided in the small-diameter cylinder hole 9b of the valve sleeve 9 in the fourth example.

Further, the first and second annular grooves 25 and 26 of the valve spool 10 in each of the above-described embodiments are omitted in the fourth embodiment, and the small-diameter spool portion 10a is provided in the valve spool 10 in the fourth embodiment. And large diameter spool 10
3b, a third annular groove 60 is formed.
The third radial groove 15 is always connected to the fifth radial hole 15. Further, the third annular groove 60 is provided with the valve spool 10.
Is not operated, the fourth radial hole 14 is shut off and the third
The power chamber 6 is connected to the radial hole 13, is disconnected from the accumulator of the hydraulic pressure source, and is connected to the reservoir for the brake hydraulic booster, and the power chamber 6 is at atmospheric pressure.
The third annular groove 60 is closed off from the third radial hole 13 and connected to the fourth radial hole 14 when the valve spool 10 moves forward, so that the power chamber 6 is connected to the reservoir for the brake hydraulic booster. , And is connected to an accumulator of a hydraulic pressure source, so that the hydraulic pressure of the accumulator is introduced into the power chamber 6. The fourth radial hole 14 and the third annular groove 60 constitute a hydraulic pressure supply valve, and the third radial hole 13 and the third annular groove 60 constitute a hydraulic pressure discharge valve. When the hydraulic pressure discharge valve is closed, the hydraulic pressure introduced into the power chamber 6 is supplied to the third annular groove 60, and the hydraulic pressure is reduced to the small diameter spool portion 10a.
And the large-diameter spool portion 10b,
As described above, the rightward force acts on the valve spool 10 due to the difference in pressure receiving area between the small diameter spool portion 10a and the large diameter spool portion 10b.

Further, the space 19 in the valve sleeve 9 is
It is always connected to the chamber 56 through an axial hole 10c and a radial hole 10c formed in the valve spool 10,
This chamber 56 is formed on the outer periphery of the valve sleeve 9 and is always connected to the third radial hole 13 through an axial groove 61. In the fourth example, the lever 27 is swingably supported by the lever support portion 5a of the power piston 5 by the first support pin 28. Other configurations of the brake hydraulic booster 1 of the fourth example and the master cylinder 33 are the same as those of the third example.

In the brake hydraulic pressure booster 1 of the fourth example configured as described above, the pressure control valve 5
A predetermined hydraulic pressure controlled by the control unit 9 is introduced. The predetermined hydraulic pressure introduced into the reaction force chamber 58 is
The desired hydraulic pressure can be arbitrarily set by the pressure control valve 59. That is, for example, it is possible to detect the pedal depression force and the pedal depression speed of the depression of the brake pedal, and to control the pressure introduced into the reaction force chamber 58 by the pressure control valve according to the detection results. Therefore, the reaction force applied to the input shaft 4 can be arbitrarily set variously, and for example, the characteristics of the brake hydraulic booster 1 such as the input-output characteristics and the input-input stroke characteristics can be freely changed. At the same time, it is possible to easily cope with a brake assist system for assisting a brake operation, a regenerative cooperative braking system, and the like. Other operational effects of the brake hydraulic booster 1 of the fourth example are the same as those of the third example.

FIG. 7 is a partial sectional view similar to FIG. 6, showing a fifth embodiment of the present invention. In the fourth example shown in FIG. 6 described above, the third annular groove 60 is formed as one groove that is long in the axial direction. However, as shown in FIG. 7, in the brake hydraulic booster 1 of the fifth example, , This one third annular groove 6
Fourth and fifth annular grooves 60a and 60b are formed by being divided into two parts in the axial direction instead of zero. Also,
Sixth and seventh annular grooves 9d and 9e are formed in the large-diameter cylinder hole 9c of the valve sleeve 9, respectively. The fourth annular groove 60a is always in communication with the sixth annular groove 9d.
The valve spool 10 is shut off from the radial hole 14 and
Can be communicated with the fourth radial hole 14 at the time of operation. On the other hand, the fifth annular groove 60b is always in communication with the seventh annular groove 9e, and is shut off from the sixth annular groove 9d and communicates with the third radial hole 13 when the illustrated valve spool 10 is not operating. When the valve spool 10 is operated, it is shut off from the third radial hole 13 and can communicate with the sixth annular groove 9d. Further, the seventh annular groove 9 e is always in communication with the fifth radial hole 15.

Further, in the fourth example, the input stroke characteristics with respect to the input are two-stage characteristics due to the two first and second return springs 31a and 31b.
In the example, one return spring 31 is provided as in the first example described above. However, unlike the first example, the return spring 31 of the seventh example has a spring characteristic in which the amount of deflection with respect to the input is initially large and gradually decreases.
That is, the first and second return springs 31 described above.
A non-linear spring having a spring characteristic approximating the two-stage characteristic according to a and 31b is used. By using this non-linear spring, the structure of this portion is simplified. Further, in the seventh example, the input shaft 4
A sliding lubricating member 63 made of a bush is provided in the sliding portion of the above. The sliding lubricating member 63 allows the input shaft 4
Can slide smoothly, and the input shaft 4
The wear of the respective sliding portions of the retainer 62 and the retainer 62 is suppressed. Other configurations of the brake hydraulic booster 1 of the fifth example and the master cylinder 33 are the same as those of the fourth example.

In the brake hydraulic booster 1 of the fifth example having the above-described structure, when the power chamber 6 is not operated, the power chamber 6 has the passage hole 22, the fifth radial hole 15, the seventh annular groove 9e, The reservoir is connected to the brake hydraulic booster reservoir through the fifth annular groove 60b, the fifth radial hole 15, the passage hole 18, and the passage hole 57, and is maintained at the atmospheric pressure. When the brake hydraulic booster 1 is operated, the input shaft 4 moves forward as in each of the above-described examples. At this time, the input shaft 4 advances smoothly by the sliding lubrication member 63. Further, the input shaft 4 strokes with respect to the input so as to exhibit the above-described two-stage characteristic due to the non-linear characteristic of the return spring 31.

Further, as the input shaft 4 advances, a spring force corresponding to the input applied to the input shaft 4 when the return spring 31 is deflected as in each of the above-described examples is generated. To the valve spool 10 and the valve spool 10 moves forward. Thereby, the fifth annular groove 60
b is cut off from the third radial hole 13 and communicates with the sixth annular groove 9 d, and the fourth annular groove 60 a communicates with the fourth radial hole 14. Then, the power chamber 6 is disconnected from the reservoir for the brake hydraulic booster and connected to the accumulator of the hydraulic pressure source, and the hydraulic pressure of the accumulator is controlled by the control valve 8 according to the input of the input shaft 4 to operate. It is supplied to the power chamber 6 as a hydraulic pressure. Hereinafter, the primary piston 37 and the secondary piston 38 of the master cylinder 33 operate in the same manner as in each of the above-described examples.

The hydraulic pressure of the accumulator controlled by the control valve 8 is controlled by the small-diameter spool portion 10a and the large-diameter spool portion 10a of the valve spool 10 in the same manner as in the above-described embodiments.
The hydraulic fluid pressure is controlled so that the hydraulic fluid pressure and the force applied to the valve spool 10 via the lever 27 according to the input of the input shaft 4 are balanced. At this time, the hydraulic fluid from the accumulator is first squeezed by the fourth radial hole 14 and the fourth annular groove 60a,
Next, since the aperture is narrowed by the sixth annular groove 9d and the fifth annular groove 60b, the aperture is narrowed in two steps. By thus squeezing the hydraulic fluid in two stages, oscillation of the control valve 8 due to pump pulsation or the like is prevented.

According to the brake hydraulic booster 1 of the fifth example, when the hydraulic fluid is controlled by the control valve 8, the hydraulic fluid is throttled in two stages. Oscillation can be more reliably prevented. Further, since the sliding lubricating member 63 is provided at the sliding portion of the retainer portion 62 with the input shaft 4, the stroke of the input shaft 4 can be made smooth, and the sliding of the input shaft 4 and the retainer portion 62 can be performed. The wear of the moving part can be suppressed. Further, since one non-linear return spring 31 is used, the stroke characteristic of the input shaft 4 by the return spring can be made substantially the same as the two-step characteristic described above, and the structure of the installation portion of the return spring is simplified. . Other functions and effects of the brake hydraulic booster 1 of the fifth example are the same as those of the fourth example. In addition, a linear bearing can be used instead of the bush for the sliding lubrication member 63 provided on the sliding portion of the retainer portion 62 with the input shaft 4. It is possible to obtain substantially the same operation and effect.

FIG. 8 is a partial sectional view similar to FIG. 7 showing a sixth embodiment of the present invention, and FIG. 9 is a partially enlarged sectional view of a portion of the control valve of the sixth embodiment. In the fifth example shown in FIG. 7 described above, the control valve 8 is constituted by a valve sleeve 9 and a valve spool 10. In the brake hydraulic booster 1 of the sixth example, the control valve 8 is a ball valve. And a valve seat on which the ball valve is attached and detached. That is, as shown in FIGS. 8 and 9, the control valve 8 is slidably supported by the valve sleeve 9 and has a ball valve 64 at one end.
, A first valve seat 66 fixed to the valve sleeve 9, and a second valve provided on a valve operating member 67 operable in a direction in which the ball valve 64 is separated from the first valve seat 66. And a seat 68.

A chamber 69 immediately to the left of the seating position of the ball valve 64 and the first valve seat 66 in the figure is always in communication with the fourth radial hole 14. Therefore, the fluid pressure of the fluid pressure source (accumulator) is constantly introduced into the chamber 69. The other end of the valve body 65 defines a control chamber 70. The control chamber 70 includes a radial hole 72 formed in a valve body support member 71 that slidably supports the valve body 65, It is always in communication with the passage hole 22 via a radial hole 73 formed in the sleeve 9 and a passage hole 74 formed in the housing 2. Therefore, the hydraulic pressure of the power chamber 6 is introduced into the control chamber 70. The valve operating member 67 is provided with an axial hole 75 opened at the tip thereof and a radial hole 76 communicating with the axial hole 75. The radial hole 76 is always in communication with the chamber 56 maintained at atmospheric pressure.

When the illustrated control valve 8 is not operated, the ball valve 64 is seated on the first valve seat 66 and is separated from the second valve seat 68. At this time, the power chamber 6 has the passage hole 22,
The radial hole 15, the annular gap 77 between the first valve seat 66 and the valve sleeve 9, the radial hole 78 drilled in the first valve seat 66, the first valve seat 66 and the valve operating member 67 Through the annular gap 79 between the ball valve 64 and the second valve seat 68, the axial hole 75, the radial hole 76, the chamber 56 and the passage hole 57 to the reservoir for the brake hydraulic booster. The communication is established and the chamber 69 is shut off, so that the pressure is set to the atmospheric pressure. Further, when the control valve 8 is operated, the valve operating member 67 moves forward, whereby the second valve seat 68 contacts the ball valve 64 to close the axial hole 75, and further the valve operating member 67 moves forward, The valve body 65 moves forward, and the ball valve 64 separates from the first valve seat 66. At this time, the power chamber 6 is shut off from the reservoir for the brake hydraulic booster by closing the axial hole 75, and the annular gap 79 communicates with the chamber 69. Therefore, the hydraulic pressure introduced into the chamber 69 is supplied to the power through the gap between the ball valve 64 and the first valve seat 66, the gap 79, the radial hole 78, the gap 77, the radial hole 15, and the passage hole 22. It is supplied to the chamber 6. Also,
At the same time, the hydraulic pressure supplied to the power chamber 6 is introduced from the passage hole 22 into the control chamber 70 through the passage hole 74, the radial hole 73, and the radial hole 72. The valve body 65 is constantly urged by the spring force of the valve spring 80 in the direction in which the ball valve 64 sits on the first valve seat 66. And
The hydraulic pressure supplied to the power chamber 6 is applied by the control valve 8 to the valve operating member 67 in which the sum of the operating force acting on the valve body 65 and the spring force of the valve spring 80 due to the hydraulic pressure in the control chamber 70 is applied to the valve operating member 67. Is controlled so as to be balanced. That is, the hydraulic pressure supplied to the power chamber 6 is controlled according to the acting force applied to the valve operating member 67.

The valve operating member 67 is constantly urged by the spring force of the spring 81 in the direction in which the second valve seat 68 is separated from the ball valve 64, and the valve operating member 67 is moved in the direction of the ball valve 64 by the pressing member 82. The spring 81 is pressed against the spring force. The pressing member 82 is slidably supported by a guide shaft 83 erected on the housing 2 via a sliding lubricating member 84 formed of a linear bearing, and is connected to the lever 27.
The input of the input shaft 4 is converted into a predetermined size via the lever 27 and transmitted to the pressing member 82, so that the pressing member 8
2 slides forward. Further, the sliding lubrication member 63 of the fifth example provided between the retainer portion 62 and the input shaft 4 is constituted by a bush.
In the example, it is constituted by a linear bearing. In addition, at least one of the two sliding lubricating members 63 and 84 may be configured by the same bush as in the fifth example. Other configurations of the brake hydraulic booster 1 of the sixth example and the master cylinder 33 are the same as those of the fifth example.

In the brake hydraulic booster 1 of the sixth example having the above-described structure, when the brake hydraulic booster 1 is not operated, the control valve 8 is in the illustrated state, and the power chamber 6 is in the state described above. And connected to the reservoir for the brake hydraulic pressure booster to maintain the atmospheric pressure. When the brake hydraulic pressure booster 1 is operated, the input shaft 4 moves forward as in each of the above-described examples, and the lever 27 rotates about the first support pin 28 by the spring force of the return spring 31. The member 82 advances.
At this time, the pressing member 82 advances smoothly by the sliding lubricating member 84. When the pressing member 82 advances, the valve operating member 67
Moves forward, the second valve seat 68 contacts the ball valve 64, and then the ball valve 64 separates from the first valve seat 66. Accordingly, as described above, the hydraulic pressure from the hydraulic pressure source is supplied to the power chamber 6 while being controlled by the control valve 8 in accordance with the acting force of the valve operating member 67. That is, the hydraulic pressure according to the input of the input shaft 4, that is, the hydraulic pressure according to the pedal effort is supplied to the power chamber 6. The primary piston 37 of the master cylinder 33 operates by the hydraulic pressure of the power chamber 6, and the brake operates in the same manner as in the above-described respective examples.

When the brake pedal is released, the input shaft 4 moves backward, so that both the pressing member 82 and the valve operating member 67 move backward. Then, the ball valve 64 is seated on the first valve seat 66 and the second valve seat 68 is separated from the ball valve 64. Therefore, as described above, the power chamber 6 communicates with the reservoir for the brake hydraulic booster, and the hydraulic fluid in the power chamber 6 is discharged to the reservoir for the brake hydraulic booster, and the power chamber 6 becomes the atmospheric pressure. . As a result, the brake hydraulic booster 1 is deactivated and the brake is released. Other functions and effects of the brake hydraulic booster 1 of the sixth example are the same as those of the fifth example.

FIG. 10 is a partial sectional view similar to FIG. 8, showing a seventh example of the embodiment of the present invention, and FIG. 11 is a partially enlarged sectional view of a portion of the control valve of the seventh example. In the above-described sixth example shown in FIGS. 8 and 9, the control valve 8 includes the valve body 65 having the ball valve 64. However, as shown in FIGS. In the power device 1, the control valve 8 includes a valve body 65 having a conical valve 85. In the seventh example, the valve sleeve 9 of the sixth example is not provided, and the valve body support member 71 that slidably supports the first valve seat 66 and the valve body 65 is supported by the hole of the housing 2. Have been.

An annular gap 79 between the first valve seat 66 and the valve operating member 67 is formed in a radial direction formed in a support member 86 fixed to the housing 2 and slidably supporting the valve operating member 67. It is always in communication with the passage hole 22 of the housing 2 via the groove 87. Further, the annular gap 79 is formed in the radial groove 8.
7, an axial hole 88 formed in the first valve seat 66, a passage hole 7
It is always in communication with the control chamber 70 via the holes 4 and the radial holes 72. Further, in the seventh example, the valve operating member 67 includes:
In the sixth example, the axial hole 75 and the radial hole 76 for discharging the hydraulic fluid in the power chamber 6 are not provided, and instead, an axial hole 89 opened at the rear end of the valve body 65 and the axial hole 89 are formed. A radial hole 90 communicating with the hole 89 is formed. The radial hole 90 is always in communication with the passage hole 18 of the housing 2 through the radial hole 91 formed in the valve body support member 71, and is always connected to the reservoir for the brake hydraulic booster from the passage hole 18. Communicating.

When the control valve 8 is not operated, the conical valve 8
5 is seated on the first valve seat 66 and separated from the second valve seat 68. At this time, the power chamber 6 includes the passage hole 22, the radial groove 87, the annular gap 79, the gap between the conical valve 85 and the second valve seat 68, the axial hole 89, the radial hole 90, and the radial hole 9.
1 and the passage hole 18 communicate with the reservoir for the brake hydraulic booster, and are shut off from the chamber 69 to be set to the atmospheric pressure. When the control valve 8 is operated, the valve operating member 67 moves forward, so that the second valve seat 68 comes into contact with the conical valve 85 to close the axial hole 89, and further the valve operating member 67 moves forward. The valve body 65 moves forward and the conical valve 85
Is separated from the first valve seat 66. At this time, the power room 6
Is closed from the reservoir for the brake hydraulic booster by closing the axial hole 89, and the annular gap 79 is closed.
Is communicated with the chamber 69. Therefore, the hydraulic pressure introduced into the chamber 69 causes a gap between the conical valve 85 and the first valve seat 66,
The power is supplied to the power chamber 6 through the gap 79, the radial groove 87, and the passage hole 22. At the same time, the hydraulic pressure supplied to the power chamber 6 is changed from the radial groove 87 to the axial hole 8.
8, the control chamber 70 through the passage hole 74 and the radial hole 72.
Has been introduced. Further, the valve body 65 is constantly urged by the spring force of the valve spring 80 in the direction in which the conical valve 85 is seated on the first valve seat 66. Also in the seventh example, the hydraulic pressure supplied to the power chamber 6 is controlled according to the acting force applied to the valve operating member 67, as in the sixth example.

Further, in the seventh example, the sliding lubricating member 6
Each of the bushings 3 and 84 is the same bush as the bush of the fifth example. The sliding lubrication member 6 of the seventh example
It goes without saying that a linear bearing can be used for at least one of the 3,84. The operation and effect of the brake hydraulic booster 1 of the seventh example are such that the ball valve 64 of the sixth example is simply changed to a conical valve 85, and the power chamber provided on the valve operating member 67 side in the sixth example. Since the hydraulic fluid discharge passage No. 6 is merely arranged on the valve body 65 side, it is substantially the same as the sixth example.

FIG. 12 is a sectional view similar to FIG. 1, showing an eighth embodiment of the present invention. The sixth example shown in FIGS. 8 and 9 is different from the sixth example shown in FIG.
In the brake hydraulic booster 1 of the example, the valve operating member 67 is slidably supported by the first valve seat 66 and is directly connected to the lever 27, and the pressing member 82 and the guide shaft of the sixth example are provided. 83 and a sliding lubrication member 84 are not provided. Further, an axial hole 75 formed in the valve operating member 67 communicates directly with the chamber 56, and a radial hole 76 is not provided.

In the eighth embodiment, the valve sleeve 9 of the sixth embodiment is not provided as in the case of the seventh embodiment, and the sliding lubrication member 63 is not provided. Further, in each of the above-described examples, the lever 27 is swingably supported by the power piston 5 by the first support pin 28, that is, the rotation fulcrum (first support pin 28) of the lever 27 is disposed on the input shaft 4 side. However, in the eighth example, the lever 27 is swingably supported by a lever support member 92 fixed to the housing 2 on the control valve 8 side by a first support pin 28. That is, in the eighth example, the lever 2
The pivot 7 (first support pin 28) is disposed on the control valve 8 side.

As described above, since the pivot of the lever 27 is disposed on the control valve 8 side, the stroke of the operating valve member 67 becomes smaller than the stroke of the input shaft 4 due to the lever ratio. The acting force applied to the actuation valve member 67 in response to the input of? However, in the case of the ball valve 64, the loss stroke is smaller than that of the spool valve in the first to fifth examples, and the ball valve 64 opposes the spring force of the valve spring 80. The operating force of the operating valve member 67 is required. Therefore, arranging the pivot of the lever 27 on the control valve 8 side is very suitable for the case of the ball valve 64. In the case of the conical valve 85 of the seventh example, the ball valve 6
The same as in the case of No. 4. The other configuration and other effects of the brake hydraulic booster 1 of the eighth example are substantially the same as those of the sixth example.

FIG. 13 is a partial sectional view similar to FIG. 5, showing a ninth embodiment of the present invention. In each of the above-described examples, a normally closed control valve is used as the control valve 8. However, in the brake hydraulic booster 1 of the ninth example, a normally open control valve is used as the control valve 8. ing. That is, the fourth and fifth radial holes 14 of the valve sleeve 9 in the third example shown in FIG.
In the ninth example, 15 is provided at the same position in the longitudinal direction of the valve sleeve 9 as shown in FIG. Also,
The second annular groove 26 is always connected not only to the fifth radial hole 15 but also to the fourth radial hole 14. In the ninth example, an accumulator is not used as a hydraulic pressure source, and only a pump (not shown) is used. Therefore, when the control valve 8 is not operated, the power chamber 6 is connected not only to the reservoir for the brake hydraulic booster but also to the pump, and is a normally open control valve. Further, the third radial hole 13 of the valve sleeve 9 and the first annular groove 25 are connected to each other with a relatively large passage area when not in operation as compared with the third example.

Further, when the input shaft 4 is not operated, the reaction force chamber 58 is provided with an axial hole 4 d formed in the front end 4 a of the input shaft 4.
And is connected to the chamber 56 through the radial hole 4e, the annular groove 5e provided in the power piston 5, and the inclined hole 5f,
When the input shaft 4 moves forward, the radial hole 4e and the annular groove 5e are shut off from the chamber 56. Further, the reaction force chamber 58 has an inclined hole 5g formed in the power piston 5 and a passage hole 2d of the housing 2.
6 is connected to the pressure control valve 59 in the same manner as in the example shown in FIG. 6, and the pressure controlled by the pressure control valve 59 is introduced into the reaction force chamber 58. Further, in the ninth example, as in the case of the first example, one return spring 31 is contracted between the input piston 3 and the retainer portion 62. Other configurations of the brake hydraulic booster 1 of the ninth example and the master cylinder 3 are the same as those of the third example.

In the brake hydraulic booster 1 of the ninth example having the above-described structure, when the pump is driven in the brake inoperative state, the pump discharge liquid from the brake hydraulic booster reservoir is discharged. The passage hole 23, the fourth radial hole 14, the second annular groove 26, the passage hole 22, the passage hole 21, the passage hole 20,
Second radial hole 12, first annular groove 25, third radial hole 1
3, and again through the passage 18 to the reservoir for the brake hydraulic booster. At this time, the first annular groove 2
Since the fifth and third radial passages 13 are connected with a large passage area, the recirculated pump discharge liquid is not restricted at all, and no hydraulic pressure is generated.

When the brake is operated, when the input shaft 4 moves forward, the lever 27 rotates counterclockwise as in the above-described embodiments, and the valve spool 10 moves forward. Then, the first
Since the area of the passage between the annular groove 25 and the third radial passage 13 is gradually reduced, the pump discharge liquid flowing back is restricted,
Hydraulic pressure is generated in the annular groove 25. This hydraulic pressure is also introduced into the power chamber 6, and the primary piston 3 is moved in the same manner as in the third embodiment.
7 operates forward, the master cylinder 33 generates master cylinder pressure, and two-system brakes operate. At this time,
The hydraulic pressure in the first annular groove 25 acts on the valve spool 10 as in the third example described above, and a rightward force is applied to the valve spool 10 by the hydraulic pressure in the first annular groove 25 due to the difference in pressure receiving area. Then, as in the third example described above, the power chamber 6 is adjusted so that the spring force of the return spring 31 according to the input, the force of the hydraulic pressure of the first annular groove 25, and the spring force of the spool return spring 32 are balanced. Is controlled, and the hydraulic pressure in the power chamber 6 becomes a pressure according to the input.

Further, since only one return spring 31 is provided, in the ninth example, the input-input stroke characteristic is one straight line having a predetermined inclination as in the case of the first example. It becomes the characteristic represented by. Further, when the input shaft 4 advances, the radial hole 4e and the annular groove 5e are cut off, the reaction force chamber 58 is cut off from the chamber 56, that is, the reservoir for the brake hydraulic booster, and controlled by the pressure control valve. Hydraulic pressure is introduced into the reaction chamber 58. This reaction chamber 5
8 reacts on the input shaft 4 to generate a reaction force.
And transmitted to the driver.

When the brake pedal is released, the controlled hydraulic pressure from the pressure control valve is no longer introduced into the reaction force chamber 58, and the input shaft 4 and the valve spool 10 are retracted as in the above-described embodiments. However, since the passage area between the first annular groove 25 and the third radial passage 13 gradually increases, the pump discharge liquid flowing back cannot be throttled, and the hydraulic pressure generated in the first annular groove 25 disappears. For this reason, the hydraulic pressure introduced into the power chamber 6 is also discharged, and the output of the brake hydraulic pressure booster 1 is canceled as in the above-described respective examples, and the master cylinder 3
3, each piston 37, 38 returns to the inactive position,
The brake is released.

Further, the retreat of the input shaft 4 causes the radial hole 4
e and the annular groove 5e are connected again, and the pressure liquid introduced into the reaction force chamber 58 is introduced into the chamber 56 through the axial hole 4d, the radial hole 4e, the annular groove 5e, and the inclined hole 5f, Further, the fluid is discharged to the reservoir for the brake hydraulic booster through the passage hole 57 and the passage hole 18. Other functions and effects of the brake hydraulic booster 1 of the ninth example are the same as those of the third example.

In each of the above embodiments, the hydraulic booster of the present invention is described using a lever type hydraulic booster using a lever as the hydraulic booster. The present invention can be applied to a hydraulic booster that does not use a lever. In each of the above-described examples, the hydraulic booster of the present invention is applied to the brake hydraulic booster. However, the hydraulic booster of the present invention can be applied to other hydraulic boosters other than the brake.

[0093]

As is apparent from the above description, according to the hydraulic booster of the present invention, the control valve is provided with a non-operating force acting by the operating hydraulic pressure and an operating force acting by the elastic member in the operating direction. Since the actuator is operated in accordance with the input of the input member so as to be balanced, and when the hydraulic pressure source operates in a normal state, the position of the pivot point of the lever is held constant regardless of the stroke of the input member. The function as a stroke simulator can be exhibited. Therefore,
The hydraulic booster can be operated by separating the input side and the output side, and in this case, the hydraulic booster can exhibit the function of a stroke simulator, so that the input stroke of the input member can be secured, The input stroke of the input member can be variously set without being affected by the control situation on the output side prior to the actuator.

Further, since the control valve and the lever of the conventional hydraulic booster can be used for the control valve and the lever of the present invention with almost no change, the hydraulic booster of the present invention has special components. , And can be inexpensive with a simple structure.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a brake hydraulic booster to which a first embodiment of a hydraulic booster according to the present invention is applied.

FIG. 2 is a partially enlarged sectional view of a control valve and a lever portion of the brake hydraulic booster shown in FIG.

FIG. 3 is a partially enlarged cross-sectional view of a master cylinder portion shown in FIG.

FIG. 4 is a partial sectional view showing a second example of the embodiment of the present invention.

FIG. 5 is a partial sectional view showing a third example of the embodiment of the present invention.

FIG. 6 is a partial sectional view showing a fourth example of the embodiment of the present invention.

FIG. 7 is a partial sectional view showing a fifth example of the embodiment of the present invention.

FIG. 8 is a partial sectional view showing a sixth example of the embodiment of the present invention.

9 is a partially enlarged sectional view of a portion of the control valve of the sixth example shown in FIG.

FIG. 10 is a partial sectional view showing a seventh example of the embodiment of the present invention.

FIG. 11 is a partially enlarged sectional view of a portion of the control valve of the seventh example shown in FIG. 8;

FIG. 12 is a sectional view showing an eighth example of the embodiment of the present invention.

FIG. 13 is a partial sectional view showing a ninth example of the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Brake hydraulic booster, 2 ... Hydraulic booster housing, 3 ... Input piston, 4 ... Input shaft, 5 ... Power piston, 6 ... Power chamber, 8 ... Control valve, 9 ... Valve sleeve,
9a: step, 10: valve spool, 27: lever, 2
8 First support pin, 29 Valve actuating member, 30 Second support pin, 31 Return spring, 31a First return spring, 31b Second return spring, 32
... Spool return spring, 33 ... Master cylinder, 37 ... Primary piston, 38 ... Secondary piston, 58 ... Reaction chamber, 63 ... Sliding lubrication member, 64 ... Ball valve, 65 ... Valve, 66 ... First valve seat, 67: valve operating member, 68: second valve seat, 70: control pressure chamber, 85: sliding lubrication member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Yamaga 2-11-6 Shinmeicho, Higashimatsuyama-shi, Saitama Bosch Brake System Co., Ltd. (72) Inventor Mitsuru Tsunoda 2--11 Shinmeicho, Higashimatsuyama-shi, Saitama No. 6 Bosch Brake System Co., Ltd. (72) Inventor Hiroaki Niino 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside Denso Corporation (72) Inventor Kazuya Maki 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture (72) Inventor Mamoru Sawada 1-1-1 Showa-cho, Kariya-shi, Aichi F-term (reference) 3D048 BB25 BB37 BB52 CC14 GG12 GG13 GG16 GG17 GG21 GG23 GG27 GG36 HH75 PP10 QQ07

Claims (9)

[Claims] An input member that strokes with an input applied during operation, and an operation that is controlled by the input member to control a hydraulic pressure of a hydraulic pressure source in accordance with an operation amount of the input member to operate an actuator. At least a control valve for generating a hydraulic pressure, wherein the working hydraulic pressure acts on the control valve in a non-operating direction, and an elastic member is disposed between the control valve and the input member. The operating force of the elastic member according to the operation amount of the input member is applied to the control valve in the operating direction, and the control valve is operated by the operating force of the hydraulic fluid and the elastic member. A hydraulic booster characterized in that the operation is controlled in accordance with the operation amount so as to balance the acting force. 2. The control valve comprises a spool valve, and the spool valve is operated and controlled by an operation force of the elastic member being applied in an operation direction and a hydraulic fluid pressure being applied in a non-operation direction. The valve spool is operated and controlled in accordance with an input from the input member so that the acting force of the hydraulic fluid acting on the valve spool and the acting force of the elastic member are balanced. The hydraulic booster according to claim 1, wherein 3. A two-stage spool valve comprising a first throttle valve and a second throttle valve, wherein a flow of a hydraulic fluid is firstly throttled by the first throttle valve and then by the second throttle valve during operation. 3. The hydraulic booster according to claim 2, wherein the throttle is performed. 4. The control valve comprises a ball valve or a conical valve, wherein the ball valve or the conical valve is acted on by an operating force of the elastic member in an operating direction and the operating fluid pressure is acted on in a non-operating direction; 2. The liquid according to claim 1, wherein the operation is controlled in accordance with an input from the input member so that the operation force of the hydraulic fluid and the operation force of the elastic member are balanced. Power booster. 5. The control device according to claim 5, wherein the elastic member is provided coaxially with the input member, and the control valve is provided at a predetermined interval in the input portion, and a gap between the elastic member and the control valve is provided. A lever that is rotated by an acting force of the elastic member according to an operation amount of the input member to act on the control valve in an operating direction, and a position of a rotation fulcrum of the lever corresponds to a stroke of the input member. Irrespective of the constant, and the control valve is controlled to operate in response to an input from the input member so that the operating force by the hydraulic pressure and the operating force by the rotation of the lever are balanced. The hydraulic booster according to any one of claims 1 to 4, wherein: 6. The input member is slidable with respect to the lever, and a sliding lubrication member is provided at a sliding portion between the input member and the lever. The hydraulic booster according to claim 5, wherein 7. The hydraulic booster according to claim 6, wherein the sliding lubrication member is a bush or a linear bearing. 8. The hydraulic boost according to claim 5, wherein a pivot point of the lever is arranged on one of the input member side and the control valve side. apparatus. 9. The hydraulic booster according to claim 1, wherein the elastic member comprises a plurality of springs or a non-linear spring.