JP2000344173A - Brake system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake system for a vehicle equipped with a proportional booster valve that can generate booster pressure to be boosted in proportion to the output pressure of a master cylinder without increasing the unspring load of a vehicle. SOLUTION: This device is provided with a master cylinder M and proportional booster valves V1, V2 to draw out the booster pressure in proportion to the output pressure of the master cylinder M from a hydraulic source S to a booster hydraulic chamber. To one side of front wheel brakes Bfa, Bfb and rear wheel brakes Bra, Brb, the output parts 11, 12 of the master cylinder M are connected and to the other side, the booster hydraulic chambers of the proportional booster valves V1, V2 are respectively connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a vehicle, and more particularly to a master cylinder output port operated by a driver depending on one of a front wheel brake and a rear wheel brake and an output oil pressure from the output port. The present invention relates to an improvement of a vehicle brake device which is connected to a boosting means for generating a hydraulic pressure which has been boosted by pressure, and which operates the other of a front wheel brake and a rear wheel brake by the hydraulic pressure generated by the boosting means.

[0002]

2. Description of the Related Art Such a brake device is disclosed in, for example,
It is already known as disclosed in JP-A-50972.

[0003]

In the brake device disclosed in the above publication, when the front wheel brake is operated by the output hydraulic pressure of the front wheel master cylinder, the booster is operated by a reaction torque generated in the front wheel brake. It consists of a secondary master cylinder.

Therefore, the secondary master cylinder is
Because of its function, it must be installed near the wheels, which increases the unsprung load of the vehicle and impairs the riding comfort to some extent.

The present invention has been made in view of such circumstances, and has been made in consideration of the above circumstances, without increasing the unsprung load of a vehicle, a proportional booster that can generate a boost hydraulic pressure that is increased in proportion to the output hydraulic pressure of a master cylinder. An object of the present invention is to provide a vehicle brake device provided with a valve.

[0006]

To achieve the above object, the present invention provides a master cylinder operated by an operator, a hydraulic pressure source, and a boost hydraulic pressure proportional to the output hydraulic pressure of the master cylinder. A proportional booster valve that draws from the power source to the booster hydraulic chamber. The output port of the master cylinder is connected to one of the front wheel brake and the rear wheel brake, and the booster hydraulic chamber of the proportional booster valve is connected to the other. This is the feature of 1.

According to the first feature, when the master cylinder operates, the output hydraulic pressure is supplied to one of the front wheel brake and the rear wheel brake to operate it. In the proportional booster valve, the boosted hydraulic pressure which is boosted in proportion to the output hydraulic pressure of the master cylinder is drawn from the hydraulic pressure source into the boosted hydraulic chamber, and the boosted hydraulic pressure is supplied to the other of the front wheel brake and the rear wheel brake. Activate it.

[0008] As described above, the proportional pressure increasing valve draws a boosted hydraulic pressure increased in proportion to the output hydraulic pressure of the master cylinder from the hydraulic pressure source and supplies it to the other wheel brake. And the hydraulic power source can be freely installed on the body frame above the suspension spring of the vehicle, and by such an installation, it is possible to suppress the increase of the unsprung load of the vehicle and maintain good ride comfort. it can.

By the way, almost all the pressure oil sent from the master cylinder is supplied to one of the wheel brakes, so that the delivery amount, that is, the operation stroke of the operation member of the master cylinder can be reduced.

On the other hand, the other wheel brake operated by the boost hydraulic pressure can exert a sufficient braking force even if it is configured to be small.

The present invention also provides a front wheel brake and a rear wheel brake, one of which is a first wheel brake, and the other of which is a second wheel brake, wherein at least the first wheel brake includes independent primary and secondary wheel cylinders. The output ports of the first master cylinder and the second master cylinder, which are individually operated by the operator, are connected to the primary wheel cylinder of the first wheel brake and the wheel cylinder of the second wheel brake, respectively. A proportional booster valve for drawing a boosted hydraulic pressure proportional to the output hydraulic pressure of one master cylinder from the hydraulic pressure source to the boosted hydraulic chamber; and the boosted hydraulic chamber of the proportional booster valve is connected to the secondary wheel cylinder of the first wheel brake. The connection is a second feature.

According to the second feature, like a motorcycle, first and second masters for operating a first wheel brake (for example, a front wheel brake) and a second wheel brake (for example, a rear wheel brake) respectively. In a cylinder equipped with a cylinder, even when only the first master cylinder is operated, its output hydraulic pressure activates the first wheel brake, and its output hydraulic pressure acts on the proportional pressure-increasing valve to increase the boost hydraulic pressure in proportion to the output hydraulic pressure. Is pulled out from the hydraulic pressure source, thereby operating the second wheel brake, so that both the first and second brakes can be operated.

Also in this case, the proportional booster valve and the hydraulic pressure source can be freely installed on the vehicle body frame above the suspension spring of the vehicle. Therefore, such installation reduces the unsprung load of the vehicle. It can maintain good ride comfort. Further, almost all pressure oil sent from the first master cylinder is supplied to the first wheel brake, so that the amount of pressure oil sent, that is, the operation stroke of the first master cylinder can be reduced.

Further, the present invention provides a front wheel brake with independent primary wheel cylinders and secondary wheel cylinders, and a rear wheel brake with independent primary wheel cylinders and secondary wheel cylinders, respectively. The output ports of the front wheel master cylinder and rear wheel master cylinder that are individually operated
A first proportional booster valve connected to the next wheel cylinder and the primary wheel cylinder of the rear wheel brake, respectively, for drawing a hydraulic pressure source and a boosted hydraulic pressure proportional to the output hydraulic pressure of the front wheel master cylinder from the hydraulic pressure source to the boosted hydraulic chamber. And a second proportional booster valve for drawing a booster hydraulic pressure proportional to the output hydraulic pressure of the rear wheel master cylinder from the hydraulic pressure source to the booster hydraulic chamber. The booster hydraulic chamber of the first proportional booster valve is connected to the rear wheel. A third feature is that the booster hydraulic chamber of the second proportional booster valve is connected to the secondary wheel cylinder of the front wheel brake, and the booster hydraulic chamber of the second proportional booster valve is connected to the secondary wheel cylinder of the brake.

According to the third feature, a motorcycle equipped with a front wheel master cylinder and a rear wheel master cylinder for operating a front wheel brake and a rear wheel brake, respectively, such as a motorcycle, wherein only the front wheel master cylinder is used. During the operation, the output hydraulic pressure is supplied to the primary wheel cylinder of the front wheel brake, and the output hydraulic pressure acts on the first proportional booster valve to draw a boost hydraulic pressure proportional to the output hydraulic pressure from the hydraulic pressure source. Since it is supplied to the secondary wheel cylinder of the rear wheel brake, both the front wheel and the rear wheel brake can be operated.

Further, even when only the rear wheel master cylinder is operated, the output oil pressure is supplied to the primary wheel cylinder of the rear wheel brake, and the output oil pressure acts on the second proportional booster valve. Is extracted from the hydraulic pressure source and supplied to the secondary wheel cylinder of the front wheel brake, so that both the front wheel and the rear wheel brake can be operated.

In this case as well, the first and second proportional booster valves and the hydraulic pressure source can be freely installed on the vehicle body frame above the suspension spring of the vehicle. An increase in lower load can be suppressed, and good ride comfort can be maintained. Also, almost all pressure oil sent from the front wheel master cylinder is supplied to the front wheel brake, and almost all pressure oil sent from the rear wheel master cylinder is supplied to the rear wheel brake. A small amount is sufficient, and the operation stroke of the master cylinder can be reduced.

Further, in the present invention, in addition to the third feature, a fourth feature is that the first and second proportional booster valves are configured so that their output characteristics are different from each other.

According to the fourth feature, by making the output characteristics of the first and second proportional booster valves different, it is possible to make the operation characteristics of the front wheel and the rear wheel brake different, thereby making it suitable for vehicle use. A suitable brake device can be provided relatively easily.

Still further, according to the present invention, in addition to the third feature, the effective pressure receiving area of the secondary wheel cylinder of the front wheel brake is set smaller than the effective pressure receiving area of the primary wheel cylinder of the rear wheel brake. The effective pressure receiving area of the secondary wheel cylinder of the brake is set smaller than the effective pressure receiving area of the primary wheel cylinder of the front wheel brake, and when the front cylinder master cylinder operates, the braking force of the front wheel brake becomes larger than that of the rear wheel brake. A fifth feature is that the braking force of the rear wheel brake is made larger than that of the front wheel brake when the rear wheel master cylinder is operated.

According to the fifth feature, when the front-wheel master cylinder is operated, the front-wheel and rear-wheel brakes are operated in an interlocking manner in which the front-wheel brake is emphasized, and when the rear-wheel master cylinder is operated, the rear-wheel brake is operated. The emphasis type is an interlocking operation mode of the front wheel and the rear wheel brake, and a good brake feeling without a sense of incompatibility similar to a non-interlocking brake device of a general motorcycle can be obtained.

Still further, according to the present invention, in addition to any one of the second to fifth features, the proportional booster valve is operated after the output hydraulic pressure of the corresponding master cylinder rises beyond a certain level. A sixth feature is that the processing is started.

According to the sixth feature, the operation is started between one wheel brake operated by the output hydraulic pressure of the master cylinder and the other wheel brake operated by the boosted hydraulic pressure output by the proportional booster valve. Timing deviation can be given.

Still further, according to the present invention, in addition to any one of the third to fifth features, the second proportional booster valve is provided after the output hydraulic pressure of the rear wheel master cylinder rises beyond a certain level. A seventh feature is that the operation is started.

According to the seventh feature, when the rear wheel master cylinder is operated, the operation start timing of the front wheel brake is delayed from that of the front wheel brake, so that the jackknife phenomenon of the vehicle body can be prevented.

The present invention is further characterized in that, in addition to any one of the second to seventh aspects, the hydraulic pressure source is provided with an operation stopping means capable of arbitrarily disabling the hydraulic pressure source.

According to the eighth feature, the hydraulic pressure source S can be deactivated by the operation of the operation stopping means, and the function of the proportional pressure increasing valve can be stopped. In this way, the front and rear wheel brakes can be operated in a conventional general independent operation mode as required.

[0028]

Embodiments of the present invention will be described below based on embodiments of the present invention shown in the accompanying drawings.

FIGS. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a hydraulic circuit diagram of an automobile brake device, FIG. 2 is an enlarged vertical sectional view of a proportional pressure increasing valve in FIG. 5 to 5 show a second embodiment of the present invention. FIG. 3 is a hydraulic circuit diagram of a motorcycle brake device, and FIG. 4 is an enlarged vertical sectional view of a first proportional booster valve and a front wheel brake in FIG. 5 is an enlarged vertical sectional view of a second proportional pressure increasing valve and a rear wheel brake in FIG. 3, and FIG. 6 is a hydraulic circuit diagram showing a longitudinal section of a main part of a motorcycle brake device according to a third embodiment of the present invention.

First, a description will be given of a first embodiment in which the present invention is applied to an automobile brake device.

Referring to FIG. 1, the vehicle brake device
Is operated by the operator via the brake pedal P
It has a tandem type master cylinder M. This master serial
1st and 2nd output ports 1₁, 1_TwoFirst to
And second output oil passage 2₁, 2_TwoExtend respectively. First out
Power oil passage 2₁Is bifurcated downstream, one of which is
Connected to the left rear wheel brake Bra that brakes the left rear wheel,
Is the first proportional booster valve V ₁Is connected to the input unit. Also the
2 output oil passage 2_TwoAlso diverges on the downstream side.
Is connected to the right rear wheel brake Brb that brakes the right rear wheel.
And the other is a second proportional booster valve V_TwoIs connected to the input unit.

The first and second proportional pressure control valve V _1, V _2, the first and second output ports 1 _1, 1 ₂ of the output hydraulic pressure common hydraulic source proportional to boosting hydraulic pressure S of the master cylinder M, respectively intended to be pulled out outputs from the first and second extending from the first and second proportional output portion of the boosting valve V _1, V ₂
The booster oil passages 3 ₁ and 3 ₂ are respectively connected to left and right front wheel brakes Bfa and Bfb for braking left and right front wheels.

The hydraulic pressure source S is driven by the electric motor 4 to draw hydraulic oil from the reservoir 5,
An accumulator 7 accumulates the discharge hydraulic pressure of the hydraulic pump 6. The electric motor 4 is connected to a battery 9 via a normally open contact 8 a of a relay 8, and is connected to a circuit for connecting a coil 8 b of the relay 8 to the battery 9, and is turned off when the hydraulic pressure of the accumulator 7 exceeds a specified value. The hydraulic pressure detection switch 10 is inserted and connected. Therefore, if the hydraulic pressure of the accumulator 7 is less than the specified value, the relay 8
Is turned on, and the electric motor 4 operates to drive the hydraulic pump 6. When the hydraulic pressure of the accumulator 7 exceeds a specified value, the hydraulic pressure detection switch 10 is turned off, and therefore the relay 8 is also turned off, and the drive of the hydraulic pump 6 by the electric motor 4 is automatically stopped. In this way, the accumulator 7 is always stored with the specified hydraulic pressure.

As shown in FIG. 2, the casing 13 of the first proportional pressure increasing valve Vf has a cap 15 joined at one end with a partition plate 14 interposed therebetween, and a lid plate 16 joined at the other end. The cap 15 has a bottomed first cylinder hole 17 whose opening surface is closed by the partition plate 14, and the inside of the cylinder hole 17 is partitioned by a control piston 18 slidably fitted therein. an atmospheric pressure chamber 19 of the plate 14 side, the same is divided into an opposite side of the control hydraulic chamber 20, the first output fluid passage 2 ₁ of the other downstream end connected to the control hydraulic chamber 20.

The casing 13 has a bottomed second cylinder hole 21 whose opening surface is closed by a partition plate 14, into which a valve piston 22 is slidably fitted. Return spring 2 urged toward partition plate 14
3 are accommodated.

The partition plate 14 is provided with a through hole 24 in the center thereof, while the center of the control piston 18 is loosely penetrated through the through hole 24 and abuts on the end face of the valve piston 22. A small shaft 18s protrudes, and the control piston 18 can push the valve piston 22 via the small shaft 18s.

The valve piston 22 is provided with a through hole 25 communicating between both end surfaces thereof, and a groove 26 communicating the through hole 25 with the through hole 24 on the surface facing the partition plate 14. Each part in the second cylinder hole 21 of the casing 13 is communicated with the atmospheric pressure chamber 19. This second cylinder hole 21
Alternatively, a return oil passage 27 is connected to the atmospheric pressure chamber 19, and a downstream end of the return oil passage 27 is connected to the suction oil passage 11 that connects the reservoir 5 and the hydraulic pump 6.

A bottomed mounting hole 28 is formed in the casing 13 so as to be axially aligned with the second cylinder hole 21 with a partition wall 13w integral with the casing 13 and closed at the opening surface by the cover plate 16.
A valve housing 29 is fixedly mounted on the valve housing 29 so that the booster hydraulic chamber 3 is provided at the bottom of the mounting hole 28.
0 is defined. This from said boosting hydraulic pressure chamber 30 first Bairyokuaburaro 3 ₁ extends.

The valve piston 22 is integrally formed with a reaction force piston 31 which slidably and oil-tightly penetrates through the partition wall 13w and has a front end facing the boosted hydraulic chamber 30. This reaction force piston 31 has a sufficiently smaller diameter than the control piston 18.

The accumulator 7 is provided in the valve housing 29.
A first communication oil passage 39 is provided for connecting the high-pressure oil passage 34 extending from the first hydraulic oil passage 30 to the booster hydraulic chamber 30, and an inlet valve 33 is interposed in the first communication oil passage 39. The inlet valve 33 is provided with a valve chamber 35 formed in the first communication oil passage 39 and the valve chamber 35.
And a valve hole 36 formed in the first communication oil passage 39 so as to communicate with the boosted hydraulic chamber 30 and a valve hole 3 accommodated in the valve chamber 35.
A check valve 37 which is spring-biased to close the check valve 6;
The valve opening rod 38 opens the check valve 37 when pushed by the end face of the reaction force piston 31. At that time, the inlet valve 33 is eccentrically arranged with respect to the reaction force piston 31 so that the valve opening rod 38 does not interfere with a second communication oil passage 41 described later that opens to the end face of the reaction force piston 31.

The valve piston 22 and the reaction force piston 31
The booster hydraulic chamber 30 is connected to the valve piston 22 in the atmospheric pressure chamber 1.
A second communication oil passage 41 connected to the groove 26 communicating with the groove 9 is provided, and an outlet valve 40 is interposed in the second communication oil passage 41. The outlet valve 40 includes a valve chamber 42 formed in the second communication oil passage 41 and a valve chamber 42 formed in the groove 2 of the valve piston 22.
The valve hole 43 formed in the second communication oil passage 41 to communicate with
A check valve 44 housed in the valve chamber 42 and urged by a spring to close the valve hole 43, and a valve-opening rod 45 penetrating the valve hole 43 loosely and facing the check valve 44.
When the valve piston 22 retreats, the valve-opening rod 45 moves
When pushed by 4, the check valve 44 is opened. At this time, the outlet valve 40 is eccentrically arranged with respect to the small shaft 18s in order to avoid interference between the valve rod 45 and the small shaft 18s.

The second proportional pressure increasing valve V ₂ is connected to the control hydraulic chamber 2
0 the second output fluid passage 2 ₂ of the other downstream end connected to,
Except that the doubled force hydraulic chamber 30 fourth Bairyokuaburaro 3 ₂ upstream end of is connected, and a first proportional booster valve V ₁ same configuration as.

Next, the operation of the first embodiment will be described.

[0044] Upon actuation of the master cylinder M by depression of the brake pedal P by the operator, the first and second output ports 1 _1, the output hydraulic pressure from 1 _2, first and second output fluid passage 2 _1, through 2 _2, first, the left and right rear wheel brakes Bra, since it is supplied to Brb,
These brakes Bra and Brb can be operated.

The first and second output ports 1 ₁ , 1 ₂
Is also supplied to the control hydraulic chamber 20 of the first and second proportional boost valves V ₁ and V ₂ through the first and second output oil passages 2 ₁ and 2 ₂ .

When the hydraulic pressure supplied to each control hydraulic chamber 20 exceeds a predetermined value defined by the set load of the return spring 23, the control piston 18 is caused by the hydraulic pressure to return.
In the outlet valve 40, the check valve 44 is closed because the valve-opening rod 45 is released from the partition plate 14.
Since the reaction piston 31 pushes the valve-opening rod 38 of the inlet valve 33 by the advance of 2, the check valve 37 is opened. Then
The hydraulic pressure of the accumulator 7 is transmitted to the boost hydraulic chamber 30 through the inlet valve 33. The hydraulic pressure acts on the end face of the reaction force piston 31 to exert a reaction force.
2 and the control piston 18 are urged in the backward direction. As a result, when the reaction force is larger than the pressing force of the control piston 18 by the hydraulic pressure of the control hydraulic chamber 20, both pistons 18, 2
2 retreats, closes the inlet valve 33 and the outlet valve 4
0, whereby the supply of hydraulic pressure from the accumulator 7 to the booster hydraulic chamber 30 is cut off, and the booster hydraulic chamber 3 is opened.
Oil pressure is leaked from 0 to the atmospheric pressure chamber 19 side. When the pressing force of the control piston 18 by the hydraulic pressure in the control hydraulic chamber 20 balances the reaction force, the inlet valve 33 and the outlet 40 are both closed, and the hydraulic pressure in the boost hydraulic chamber 30 is maintained. When the pressing force of the control piston 18 due to the oil pressure in the control hydraulic chamber 20 exceeds the above-described reaction force, the pistons 18 and 22 advance again to close the outlet valve 40 and open the inlet valve 33. Then, the supply of the hydraulic pressure from the accumulator 7 to the boost hydraulic chamber 30 is restarted. By repeating such an operation,
The hydraulic pressure of the boost hydraulic chamber 30 is controlled to increase in proportion to the hydraulic pressure of the control hydraulic chamber 20, that is, the output hydraulic pressure of the master cylinder M.

The oil in the booster hydraulic chamber 30 controlled as described above
The pressure is the first proportional pressure increase valve V₁From the first booster oil passage 3
₁Through to the left front wheel brake Bfa and through the second proportional boost
Valve V _TwoFrom the fourth booster oil passage 3_TwoThrough the front right wheel
Rake Bfb.
Bfa and Bfb can be operated strongly with boost hydraulic pressure.
Can be.

As described above, the first and second proportional booster valves V ₁ , V ₂ draw the boosted hydraulic pressure proportional to the output hydraulic pressure of the master cylinder M from the hydraulic pressure source S, and draw the boosted hydraulic pressure from the left and right front wheel brakes Bfa, Bfb. Therefore, these proportional pressure-up valves V ₁ , V ₂ and the hydraulic source S can be freely installed on the body frame above the suspension spring of the vehicle. The increase in the unsprung load of the vehicle can be suppressed, and good riding comfort can be maintained. Further, almost all of the pressure oil sent from the master cylinder M is supplied to the left and right rear wheel brakes Bra and Brb, so that the delivery amount, that is, the depression stroke of the brake pedal P can be reduced.

Next, a second embodiment in which the present invention is applied to a motorcycle brake device will be described with reference to FIGS.

As shown in FIGS. 3 and 4, a steering wheel H of a motorcycle has a front wheel master cylinder Mf (first master cylinder) operated by a brake lever L.
Is attached. On both sides of the front wheel Wf, a pair of left and right first and second disc brakes Bf ₁ for braking the front wheel Wf,
Bf ₂ is disposed, and the first and second disc brakes Bf ₁ and Bf ₂ constitute a front wheel brake Bf.

First and second disc brakes Bf ₁ , Bf
f ₂ is a intended to be left-right symmetrical with respect to the front wheels Wf, both a brake disc 50 which is fixed to the hub side of the front wheel Wf, disposed opposite to both sides of the brake disk 50 Left and right pair of friction pads 51
a, 51b, and a brake caliper 52 straddling the brake disc 50 with the friction pads 51a, 51b interposed therebetween. The brake caliper 52 is attached to the front fork so as to be slidable in the left-right direction. , 51b are supported by a brake caliper 52 or a bracket fixed to the front fork. The brake caliper 52 includes one friction pad 51.
b, three pistons 53 ₁ , 53 ₂ , 5
3 ₁ three wheel cylinders 54 for slidably accommodating the
_1, 54 _2, 54 ₁ are juxtaposed, ₁ either side of the wheel cylinders 54, 54 _1, is a primary wheel cylinder communicating with each other and _second center wheel cylinders 54, 1
Are next wheel cylinders 54 _1, 2 is independent of the 54 _primary wheel cylinder 54 _2. The _second pressure receiving area secondary wheel cylinder 54 of the front wheel brake Bf is
Primary wheel cylinder 54 of rear wheel brake Br described later
It is set smaller than the pressure receiving area of ₁ .

Output port 5 of front wheel master cylinder Mf
5₁Output oil passage 56 extending from ₁Is on the downstream side
One is the primary wheel system of the front wheel brake Bf.
Linda 54₁And the other is connected to the first proportional pressure increasing valve V₁To
Connected.

[0053] The first proportional booster valve V ₁ was, supplies the boosting hydraulic pressure in proportion to the output hydraulic pressure of the front wheel master cylinder Mf ₂ secondary wheel cylinder 54 of the wheel brake Br after described later pulled from the hydraulic pressure source S In other words, the first proportional pressure increasing valve V
The first output fluid passage 56 ₁ is connected to the _first control hydraulic chamber 20,
Boosting hydraulic pressure chamber 30 is connected via a first Bairyokuaburaro 57 ₁ to ₂ secondary wheel cylinder 54 of the wheel brake Br after below. The first Bairyokuaburaro 57 _1, the hydraulic pressure of the upstream side becomes equal to or higher than the prescribed value, the hydraulic pressure limiting valve 58 to shut off the oil passage 57 ₁ is Kai裝. Other configurations are the same as those of the first embodiment.
And the second proportional booster valves V ₁ and V ₂ are basically the same. Therefore, in the figure, corresponding parts are denoted by the same reference numerals and description thereof is omitted.

As shown in FIGS. 3 and 5, a rear wheel master cylinder Mr (second master cylinder) operated by a brake pedal P is mounted on the body frame of the motorcycle. A rear wheel brake Br for braking the rear wheel Wr is disposed on one side of the rear wheel Wr. The rear wheel brake Br is constituted by a disk brake, and the respective disk brakes Bf ₁ , Bf _{2 of the} front wheel brake Bf are provided.
Have the same configuration as the both sides of the wheel cylinders 54 _1, 54 ₁ of the brake caliper 52 is the primary wheel cylinder, and ₂ central wheel cylinder 54 is set to ₂ secondary wheel cylinder 54. The _second pressure receiving area secondary wheel cylinder 54 of the rear wheel brake Br is
Less than ₁ of the pressure receiving area primary wheel cylinder 54 of the front wheel brake Bf is set.

In the rear wheel brake Br, parts corresponding to the disk brakes Bf ₁ and Bf ₂ of the front wheel brake Bf are denoted by the same reference numerals, and the description thereof will be omitted.

Output port 5 of rear cylinder master cylinder Mr
5_TwoOutput oil passage 56 extending from _TwoIs on the downstream side
One of them is the primary wheel system of the rear wheel brake Br.
Linda 54₁And the other is connected to the second proportional pressure increasing valve V_TwoTo
Connected.

The second proportional booster valve V ₂ draws a boosted hydraulic pressure proportional to the output hydraulic pressure of the rear wheel master cylinder Mr from the hydraulic pressure source S, and the secondary wheel cylinder 5 of the front wheel brake Bf.
4 and supplies the _2, i.e., the second proportional booster valve V ₂ of the control hydraulic chamber 20 is connected to the first output fluid passage 56 _1, boosting hydraulic pressure chamber 30, second Bairyokuaburaro 57 ₂ It is connected to _two secondary wheel cylinder 54 of the front wheel brake Bf via the. Other configurations, since the first proportional booster valve V ₁ and basically the same, in the figure, the same reference characters to corresponding parts of it.

As shown in FIG. 3, the hydraulic pressure source S is commonly used for the first and second proportional pressure increase valves V ₁ and V ₂ , and is driven by the electric motor 4 to supply hydraulic oil from the reservoir 5. It comprises a hydraulic pump 6 for sucking in, and an accumulator 7 for accumulating the discharge hydraulic pressure of the hydraulic pump 6. The electric motor 4 is connected to a battery 9 via a normally open contact 8 a of a relay 8.
And a circuit for connecting the coil 8b of the relay 8 to the battery 9, a normally-closed oil pressure detection switch 10 that is turned off when the oil pressure of the accumulator 7 exceeds a prescribed value, and a manual switch 60 that can be opened and closed arbitrarily. Stopping means) are connected in series. Therefore, if the hydraulic pressure of the accumulator 7 is less than the specified value while the manual switch 60 is on, the relay 8 is turned on and the electric motor 4 operates to drive the hydraulic pump 6. When the hydraulic pressure of the accumulator 7 exceeds a specified value, the hydraulic pressure detection switch 10 is turned off, and therefore the relay 8 is also turned off, and the drive of the hydraulic pump 6 by the electric motor 4 is automatically stopped. In this way, the accumulator 7 normally accumulates a predetermined oil pressure. Also, even while the electric motor 4 is operating,
When the manual switch 60 is turned off, the operation of the electric motor 4 can be stopped.

The operation of the second embodiment will be described.

[0060] Now, in order to brake the front wheel Wf, when operating the front wheel master cylinder Mf by operating the brake lever L, the output hydraulic pressure, the primary wheel cylinder 54 of the first output fluid passage 56 ₁ through the front wheel brake Bf ₁ , 54
_1, is supplied to the first proportional booster valve V ₁ of the control hydraulic chamber 20. Then, the hydraulic pressure supplied to the primary wheel cylinders 54 ₁ , 54 ₁ gives thrust to the primary pistons 53 ₁ , 53 ₁ , so that the primary pistons 53 ₁ , 53 ₁ move forward and brake by the reaction force. By moving the caliper 52 in the direction opposite to the primary pistons 53 ₁ , 53 ₁ , the friction pads 51 a, 51 b are pressed against both side surfaces of the brake disc 50, so that a braking force is applied to the front wheel Wf.

On the other hand, the first proportional pressure increasing valve V ₁ supplied with the hydraulic pressure to the control hydraulic pressure chamber 20 performs the same operation as the first proportional pressure increasing valve V ₁ of the previous embodiment, and pull the proportional booster oil pressure to the boosting hydraulic pressure chamber 30 from the hydraulic pressure source S to which the secondary wheel supplied to the cylinder 54 ₂ of the rear wheel brake Br through the first Bairyokuaburaro 57 _1. Then, also in the rear wheel brake Br, both friction pads 51a and 51b are pressed against both side surfaces of the brake disc 50 by the same operation as the front wheel brake Bf, so that a braking force is applied to the rear wheel Wr.

As described above, by operating only the front wheel master cylinder Mf, both the front wheel brake Bf and the rear wheel brake Br can be operated.

Incidentally, in this case, the first proportional pressure increasing valve V ₁
In this case, the operation is started after the hydraulic pressure supplied from the front wheel master cylinder Mf to the control hydraulic chamber 20 becomes equal to or more than the specified value defined by the return spring 23, so that the hydraulic pressure of the front wheel master cylinder Mf is reduced by the front wheel brake Bf. with a slight delay from the supply to the primary wheel cylinders 54 ₁ of the first
Will be boosted hydraulic pressure of the proportional booster valve V ₁ is supplied to the ₂ secondary wheel cylinder 54 of the rear wheel brake Br, therefore, by utilizing the increase of the front wheel load associated with the prior actuation of the front wheel brake Bf, the braking The effect can be enhanced.

[0064] Moreover, the primary pressure receiving area of the wheel cylinder 54 ₁ of the front wheel brake Bf is the rear wheel brake secondary wheel is greater than set pressure receiving area of the cylinder 54 ₂ of Br, the front wheel brake Bf primary wheel cylinder 54
Since the braking force by the _first hydraulic pressure is set to be larger than the braking force by the secondary wheel cylinder 54 ₂ of the hydraulic pressure of the rear wheel brake Br, a braking mode of operation emphasizes the front wheel brake Bf. Such a braking mode is generally applied to braking on a pavement having a high coefficient of friction.

[0065] Further, in order to brake the rear wheel Wr, when operating the rear wheel master cylinder Mr by operating the brake pedal P, the output hydraulic pressure, the primary of the rear wheel brake Br through the second output fluid passage 56 ₂ Wheel cylinders 54 ₁ , 54
_1, is supplied to the second proportional booster valve V ₂ of the control hydraulic chamber 20. In the rear wheel brake Br, the hydraulic pressure supplied to the primary wheel cylinders 54 ₁ , 54 ₁
3 _1, 53 ₁ operates by applying thrust on, can apply a braking force to the rear wheel Wr.

On the other hand, in the second proportional pressure increasing valve V ₂ in which the output hydraulic pressure of the rear wheel master cylinder Mr is supplied to the control hydraulic pressure chamber 20, the operation of the control hydraulic pressure chamber 20 is performed in the same manner as the first proportional pressure increasing valve V ₁ . Pull the boosting hydraulic pressure in proportion to the hydraulic pressure from the hydraulic source S to boosting hydraulic pressure chamber 30, which since the supply through the second Bairyokuaburaro 57 ₂ to ₂ secondary wheel cylinder 54 of the front wheel brake Bf, also the front wheel brake Bf By operating, a braking force can be applied to the front wheels Wf.

As described above, by operating only the rear wheel master cylinder Mr, not only the rear wheel brake Br but also the front wheel brake Bf can be operated.

By the way, in this case, the second proportional pressure increasing valve V ₂
In this case, the operation is started after the hydraulic pressure supplied from the rear wheel master cylinder Mr to the control hydraulic chamber 20 becomes equal to or more than the specified value specified by the return spring 23, so that the hydraulic pressure of the rear wheel master cylinder Mr with a slight delay from the supply to the primary wheel cylinders 54 ₁ of the wheel brake Br, the second
So that the boost pressure of the proportional booster valve V ₂ is supplied to the ₂ secondary wheel cylinder 54 of the front wheel brake Bf. Moreover, ₁ of the pressure receiving area primary wheel cylinder 54 of the rear wheel brake Br is preset larger than the _second pressure receiving area secondary wheel cylinder 54 of the front wheel brake Bf, the rear wheel brake Br primary wheel cylinders 54 ₁ of The braking force by hydraulic pressure is applied to the secondary wheel cylinder 54 _{2 of the} front wheel brake Bf.
The braking mode is set to be larger than the braking force by the hydraulic pressure, so that the braking mode is focused on the operation of the rear wheel brake Br.
Such a braking mode is generally applied to braking on a rough road having a low friction coefficient, and is effective for avoiding a jackknife phenomenon of a vehicle.

In the second embodiment, the first and second
The proportional boost valves V ₁ , V ₂ and the hydraulic pressure source S can be freely installed on the vehicle body frame above the suspension spring of the vehicle, and by such an installation, the increase in the unsprung load of the vehicle can be suppressed. Good ride comfort can be maintained. Almost all pressure oil sent from the front wheel master cylinder Mf is supplied to the front wheel Wf.
Since almost all of the pressure oil delivered by r is supplied to the rear wheel Wr, the delivery amount of the pressure oil of each master cylinder Mf, Mr, and therefore the operation stroke of the brake lever L and the brake pedal P can be reduced.

Master cylinders Mf, M for front and rear wheels
r at the same time, the front wheel and rear wheel brakes B
f and Br, all wheel cylinders 5
4 _1, 54 ₂ from the hydraulic pressure to be supplied, it is possible to exert a strong braking force.

The manual switch 60 in the hydraulic pressure source S
Is turned off, the driving of the hydraulic pump 6 by the electric motor 4 can be stopped. In this state, the operation of the front wheel and rear wheel master cylinders Mf and Mr is repeated several times, thereby accumulating the pressure in the accumulator 7. Can be emptied. By doing so, the first and second proportional pressure increasing valves V
₁ and V ₂ are the _two of the front and rear wheel brakes Bf and Br
It becomes impossible to supply the next wheel cylinder 54 _2, 54 ₂ double force hydraulic. Result, front wheel and rear wheel brake B
f and Br can be operated in a conventional general independent operation mode.

Next, a third embodiment of the present invention will be described with reference to FIG.

The third embodiment is also applied to a motorcycle brake device, but differs from the second embodiment in the following configuration.

In the second proportional pressure increasing valve V ₂ , the set load of the return spring 23 of the valve piston 22 is the first proportional pressure increasing valve V ₁
It is set smaller to much higher than that of the side of the return spring 23, also the pressure receiving area of the reaction piston 31 is formed to have a larger diameter than the pressure-receiving area of the reaction piston 31 of the first proportional booster valve V ₁ side.

Since the rest of the configuration is the same as that of the second embodiment, the same reference numerals in the drawing denote the same parts as in the second embodiment, and a description thereof will be omitted.

[0076] With the configuration as described above, since with a reduced set load of the return spring 23 in the second proportional booster valve V _2, during operation of the rear wheel master cylinder Mr, the start of the operation the second proportional booster valve V ₂ Set the timing to the first proportional pressure increase valve V ₁
The front wheel brake Bf and the rear wheel brake Br can be actuated substantially at the same time as earlier than the operation start timing of, and the braking effect can be enhanced. Also, the second proportional booster valve V
_Since the pressure receiving area of the reaction force piston 31 in Step ₂ is set to be large, the boosting ratio of the proportional pressure increasing valve V2 is reduced to weaken the braking force of the front wheel brake Bf when operating the rear wheel master cylinder Mr. The effect of emphasizing the operation of the wheel brake Br can be enhanced.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist of the present invention. For example, in the second and third embodiments, the front wheel brake Bf side of the disc brake Bf ₁ or B
It can be configured only by f _2.

[0078]

As described above, according to the first aspect of the present invention, the master cylinder operated by the operator, the hydraulic pressure source, and the boosted hydraulic pressure proportional to the output hydraulic pressure of the master cylinder are applied to the hydraulic pressure source. And a proportional booster valve that draws the booster hydraulic chamber from the master cylinder. The output port of the master cylinder is connected to one of the front wheel brake and the rear wheel brake, and the booster hydraulic chamber of the proportional booster valve is connected to the other. , One of the front wheel brake and the rear wheel brake can be operated by the output hydraulic pressure, and the other of the front wheel brake and the rear wheel brake can be activated by the boosted hydraulic pressure of the proportional pressure increasing valve. In addition, the proportional pressure increasing valve and the hydraulic pressure source can be freely installed on the vehicle body frame above the suspension spring of the vehicle. Can be maintained. Further, almost all the pressure oil sent from the master cylinder is supplied to one of the wheel brakes, so that the delivery amount, that is, the operation stroke of the operation member of the master cylinder can be reduced. On the other hand, the other wheel brake operated by the boost hydraulic pressure can exert a sufficient braking force even if it is configured to be small.

According to a second feature of the present invention, one of the front wheel brake and the rear wheel brake is a first wheel brake and the other is a second wheel brake, and at least the primary wheel cylinder is independent of the first wheel brake. And a secondary wheel cylinder, and output ports of the first master cylinder and the second master cylinder individually operated by the pilot are respectively connected to the primary wheel cylinder of the first wheel brake and the wheel cylinder of the second wheel brake. , A hydraulic pressure source, and a proportional booster valve for drawing a boosted hydraulic pressure proportional to the output hydraulic pressure of the first master cylinder from the hydraulic source to the boosted hydraulic chamber. Because it is connected to the secondary wheel cylinder of the above, even if it has two master cylinders for the front wheel and the rear wheel like a motorcycle, If only the operations master cylinder,
In addition to operating the first wheel brake by the output oil pressure,
The second wheel brake can also be operated by the boosted hydraulic pressure of the proportional booster valve, and the braking operation can be simplified. Of course, also in this case, the proportional boost valve and the hydraulic pressure source can be freely installed on the body frame above the suspension spring of the vehicle. ， Good ride comfort can be maintained. The pressure oil sent from the first master cylinder is
Since almost all of the pressure oil is supplied to one of the wheel brakes, the pressure oil delivery amount, that is, the operation stroke of the first master cylinder can be reduced.

According to a third aspect of the present invention, the front wheel brake is provided with independent primary wheel cylinders and two independent wheel cylinders.
The next wheel cylinder and the rear wheel brake are provided with independent primary wheel cylinders and secondary wheel cylinders, respectively, and the output ports of the front wheel master cylinder and the rear wheel master cylinder that are individually operated by the driver are connected to the front wheel brake. Connected to the primary wheel cylinder of the rear wheel brake and the primary wheel cylinder of the rear wheel brake respectively.
A first proportional booster valve that draws a boost hydraulic pressure proportional to the output hydraulic pressure of the front wheel master cylinder from this hydraulic pressure source to the boost hydraulic chamber, and a boost hydraulic pressure proportional to the output hydraulic pressure of the rear wheel master cylinder from the hydraulic pressure source. A second proportional booster valve that draws out to the booster hydraulic chamber, wherein the booster hydraulic chamber of the first proportional booster valve is used for the secondary wheel cylinder of the rear wheel brake, and the booster hydraulic chamber of the second proportional booster valve is used for the front wheel. Since each is connected to the secondary wheel cylinder of the brake, when operating only the front wheel master cylinder, the front wheel brake can be activated by the output hydraulic pressure and the rear wheel brake can be activated by the boost hydraulic pressure of the first proportional booster valve. On the other hand, when only the rear wheel master cylinder is operated, the rear wheel brake can be operated by the output oil pressure and the front wheel brake can be operated by the boosted oil pressure of the second proportional booster valve. It is possible to further simplify the braking operations. Of course, also in this case, the first and second proportional booster valves and the hydraulic pressure source can be freely installed on the vehicle body frame above the suspension spring of the vehicle. It is possible to suppress an increase in load and maintain good ride comfort. Also, almost all pressure oil sent from the front wheel master cylinder is supplied to the front wheel brake, and almost all pressure oil sent from the rear wheel master cylinder is supplied to the rear wheel brake. A small amount is sufficient, and the operation stroke of the master cylinder can be reduced.

Further, according to a fourth aspect of the present invention,
In addition to the third feature, the first and second proportional booster valves are configured so that their output characteristics are different from each other. Therefore, by making the output characteristics of the first and second proportional booster valves different, the front wheel is increased. In addition, the operating characteristics of the rear wheel brake can be made different, so that a brake device suitable for the use of the vehicle can be provided relatively easily.

According to a fifth feature of the present invention,
In addition to the third feature, the effective pressure receiving area of the secondary wheel cylinder of the front wheel brake is set smaller than the effective pressure receiving area of the primary wheel cylinder of the rear wheel brake, and the effective pressure receiving area of the secondary wheel cylinder of the rear wheel brake. Is set smaller than the effective pressure receiving area of the primary wheel cylinder of the front wheel brake, so that the braking force of the front wheel brake is larger than that of the rear wheel brake when the front wheel master cylinder is activated, and the rear wheel is activated when the rear wheel master cylinder is activated. The braking force of the brakes is set to be greater than that of the front wheel brakes.
The front and rear wheel brakes are interlocked, and the rear wheel master cylinder is operated when the rear wheel master cylinder is operated. A good brake feeling without a sense of incompatibility can be obtained.

Further, according to a sixth aspect of the present invention,
In addition to any of the second to fifth features, the proportional pressure-increasing valve is configured such that it starts operation after the output oil pressure of the corresponding master cylinder rises beyond a certain level, so that the master cylinder is actuated. A difference in the operation start timing can be given between one wheel brake operated by the output hydraulic pressure of the other and the other wheel brake operated by the boosted hydraulic pressure output from the proportional booster valve.

According to a seventh feature of the present invention,
In addition to any of the third to fifth features, the second proportional booster valve is configured to start operation after the output hydraulic pressure of the rear wheel master cylinder rises beyond a certain level. When the rear wheel master cylinder is operated, the operation start timing of the front wheel brake can be delayed from that of the front wheel brake, thereby preventing the jackknife phenomenon of the vehicle body during sudden braking.

Further, according to an eighth aspect of the present invention,
In addition to any one of the second to seventh aspects, the hydraulic pressure source is provided with an operation stopping means capable of arbitrarily inactivating the hydraulic pressure source. Function can be stopped. Accordingly, the front and rear wheel brakes and Br can be operated in a conventional general independent operation mode as required.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of a vehicle brake device according to a first embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of a proportional pressure increasing valve in FIG. 1;

FIG. 3 is a hydraulic circuit diagram of a motorcycle brake device according to a second embodiment of the present invention.

FIG. 4 is an enlarged vertical sectional view of a first proportional pressure increasing valve and a front wheel brake in FIG. 3;

FIG. 5 is an enlarged longitudinal sectional view of a second proportional booster valve and a rear wheel brake in FIG. 3;

FIG. 6 is a hydraulic circuit diagram showing a longitudinal section of a main part of a motorcycle brake device according to a third embodiment of the present invention.

[Explanation of symbols]

Bfa: Wheel brake (front left wheel brake) Bfb: Wheel brake (front right wheel brake) Bra: Wheel brake (rear left wheel brake) Brb: Wheel brake (rear right wheel brake) Bf: First wheel brake (front wheel brake) Br: Second wheel brake (rear wheel brake) M: Master cylinder (primary master cylinder) Mf: First master cylinder (front wheel master cylinder) Mr... Second master cylinder (rear wheel master cylinder) S... Hydraulic pressure source V _1. boost valve) V ₂ ----- proportional booster valve (second proportional pressure control valve) ₁ 1 ..... output port (first output port) 1 ₂ ..... output port (second output port) 30 ···· Booster hydraulic chamber 54 ₁ ··· Primary Wheel cylinder 54 ₂ ··· Secondary wheel cylinder 55 ₁ ··· Output port (output port of first master cylinder) 55 ₂ ··· Output port (output port of second master cylinder) 60 ··· ..Operation stop means (manual switches)

Claims (8)

[Claims] 1. A master cylinder (M) operated by an operator, a hydraulic pressure source (S), and the master cylinder (M)
Proportional booster valve (V ₁ , V ₁ ) that draws a boost hydraulic pressure proportional to the output hydraulic pressure of the hydraulic pump from the hydraulic pressure source (S) to the boost hydraulic pressure chamber (30).
V ₂ ), one of the front wheel brakes (Bfa, Bfb) and the rear wheel brakes (Bra, Brb) is provided with the output port (1 ₁ , 1 ₂ ) of the master cylinder (M), and the other is provided with the proportional booster valve. A brake device for a vehicle, wherein booster hydraulic chambers (30) of (V ₁ , V ₂ ) are respectively connected. 2. One of a front wheel brake (Bf) and a rear wheel brake (Br) is a first wheel brake and the other is a second wheel brake, and at least the first wheel brake (Bf) has independent primary wheel cylinders (Bf). 54 ₁ ) and a secondary wheel cylinder (54 ₂ ), and the output ports (55 ₁ , 55 ₂ ) of the first master cylinder (Mf) and the second master cylinder (Mr) individually operated by the pilot Primary wheel cylinder (5) of one wheel brake (Bf)
4 ₁ ) and the wheel cylinder (54 ₁ ) of the second wheel brake (Br), respectively.
The hydraulic source proportional to boosting hydraulic pressure to the output pressure of the master cylinder (Mf) proportional booster valve to draw from (S) to the boosting hydraulic pressure chamber (30) (V ₁₎ and provided with, this proportional pressure control valve (V ₁₎
Of the booster hydraulic chamber (30) of the second wheel brake (Br)
A brake device for a vehicle, wherein the brake device is connected to a next wheel cylinder (54 ₂ ). 3. A primary wheel cylinder which are independent from each other in the front wheel brake (Bf) (54 ₁₎ and a secondary wheel cylinder (54 _2), also mutually independent primary wheel cylinder to the rear wheel brake (Br) (54 ₁ ) and a secondary wheel cylinder (54 ₂ ), respectively, and output ports (55 ₁ , 5 ₁ ) of the front wheel master cylinder (Mf) and the rear wheel master cylinder (Mr) individually operated by the pilot.
5 ₂ ) are connected to the primary wheel cylinder (54 ₁ ) of the front wheel brake (Bf) and the primary wheel cylinder (54 ₁ ) of the rear wheel brake (Br), respectively.
A first proportional booster valve (V ₁ ) for drawing a boost hydraulic pressure proportional to the output hydraulic pressure of the front wheel master cylinder (Mf) from the hydraulic pressure source (S) to the boost hydraulic chamber (30); output hydraulic pressure proportional to boosting hydraulic said hydraulic source mr) (second proportional booster valve to draw from S) to the boosting hydraulic pressure chamber (30) (V ₂₎ and provided with, a first proportional pressure control valve (V ₁ ) To the secondary wheel cylinder (54 ₂ ) of the rear wheel brake (Br) and the second proportional booster valve (V ₂ ).
A booster hydraulic chamber (30) is connected to a secondary wheel cylinder (54 ₂ ) of a front wheel brake (Bf). 4. The brake device for a vehicle according to claim 3, wherein the first and second proportional booster valves (V ₁ , V ₂ ) are configured so that their output characteristics are different from each other. ， Vehicle brake device. 5. The brake device for a vehicle according to claim 3, wherein the effective pressure receiving area of the secondary wheel cylinder (54 ₂ ) of the front wheel brake (Bf) is set to one of that of the rear wheel brake (Br).
The effective pressure receiving area of the secondary wheel cylinder (54 ₂ ) of the rear wheel brake (Br) is set smaller than the effective pressure receiving area of the next wheel cylinder (54 ₁ ).
f) is set smaller than the effective pressure receiving area of the primary wheel cylinder (54 ₁ ), and when the front wheel master cylinder (Mf) operates, the braking force of the front wheel brake (Bf) is larger than that of the rear wheel brake (Br). A braking device for a vehicle, wherein the braking force of the rear wheel brake (Br) is larger than that of the front wheel brake (Bf) when the rear wheel master cylinder (Mr) is activated. 6. The brake device for a vehicle according to claim 2, wherein the proportional booster valves (V ₁ , V ₂ ) and the corresponding output hydraulic pressures of the master cylinders (Mf, Mr) are adjusted. A brake device for a vehicle, characterized in that the brake device is configured to start operation after rising above a certain level. 7. A brake device for a vehicle according to claim 3, wherein said second proportional pressure increasing valve (V ₂ ) is adapted to output an output hydraulic pressure of a rear wheel master cylinder (Mr) exceeding a predetermined value. A brake device for a vehicle, characterized in that it is configured to start operating after being lifted. 8. The brake device for a vehicle according to claim 2, wherein the hydraulic pressure source (S) is provided with an operation stopping means (60) for arbitrarily stopping the operation. Vehicle braking device.