JP2719957B2 - Braking hydraulic control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Industrial application field The present invention has an input port connected to a hydraulic supply source and an output port connected to a brake device. The present invention relates to a braking hydraulic pressure control device including a hydraulic pressure source pressure control unit configured to control an input hydraulic pressure in accordance with a braking operation amount and output the output hydraulic pressure from an output port.

(2) Conventional technology Conventionally, such a braking hydraulic control device is disclosed in, for example,
-187.

(3) Problems to be Solved by the Invention By the way, in the above-mentioned conventional one, the braking pressure of the brake device is controlled by the hydraulic supply source hydraulic pressure control means. When it becomes impossible to secure the supply source hydraulic pressure, it becomes difficult to apply sufficient braking pressure to the brake device.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a brake hydraulic pressure control device capable of obtaining a sufficient braking pressure even when a sufficient hydraulic pressure is not obtained due to a malfunction of a hydraulic pressure source.

B. Configuration of the Invention (1) Means for Solving the Problems A device according to the present invention is a hydraulic device which is interlocked with a brake pedal to move forward in response to a braking operation, with a front end face of a working piston connected thereto facing a front end surface of a hydraulic piston. Auxiliary hydraulic pressure generating means in which a chamber is formed; and an input hydraulic chamber that can communicate with an output hydraulic path connected to the output port of the hydraulic supply source hydraulic control means and an output hydraulic chamber that communicates with the brake device, with both end faces facing free. A hydraulic transmission means having a piston slidably fitted to the cylinder body; interposed between the hydraulic transmission means and the brake device, and a hydraulic chamber of the auxiliary hydraulic transmission means, and branched from the output oil passage. An on-off valve that shuts off in response to an increase in oil pressure in the branch oil passage; and an oil passage interposed in the output oil passage closer to the hydraulic transmission means than the branch portion of the branch oil passage, and from the output port to the hydraulic transmission means side Allow only distribution of A first one-way valve connected in parallel with the first one-way valve, and opening the valve with a differential pressure equal to or higher than a preset valve opening pressure to flow hydraulic oil from the hydraulic transmission means side to the output port side; A second one-way valve that permits only

(2) Operation According to the above configuration, during normal braking in which the hydraulic pressure of the hydraulic supply source is normal, the hydraulic supply source hydraulic control means operates in response to the braking operation, and the output port of the hydraulic supply source hydraulic control means The hydraulic pressure is output, the hydraulic pressure in the branch oil passage leading to the output port increases, the on-off valve is shut off, and the hydraulic pressure acts on the hydraulic transmission means via the first one-way valve. Pressure is given. Also, when the hydraulic pressure of the hydraulic supply source drops abnormally, the output hydraulic pressure of the output port of the hydraulic supply source hydraulic control unit decreases, and the on-off valve opens accordingly, so that the brake pedal from the hydraulic chamber of the auxiliary hydraulic pressure generation unit The hydraulic pressure that is output in accordance with the amount of braking operation acts on the brake device to secure the braking pressure. In addition, when the on-off valve is opened, the hydraulic pressure of the brake device is prevented from escaping to the hydraulic supply source side by the hydraulic transmission means. Further, when the state shifts from the braking operation state to the non-braking operation state, the operation of the second one-way valve ensures that the opening operation of the on-off valve is performed earlier than the operation of the free piston in the hydraulic transmission means to the original position. The output hydraulic chamber in the transmission means can breathe.

(3) Embodiment Hereinafter, an embodiment in which the present invention is applied to a braking hydraulic control device for a front engine / front drive vehicle will be described with reference to the drawings.

FIG. 1 shows a hydraulic circuit according to an embodiment of the present invention. A left front wheel brake device _BFL and a right front wheel brake device _BFR are mounted on a left front wheel and a right front wheel of a vehicle, respectively. B _RL for the rear left wheel
And a right rear wheel brake device B _RR are respectively mounted. On the other hand, the brake pedal 1
Auxiliary hydraulic pressure generating means 3 for outputting a hydraulic pressure according to the amount of depression of the vehicle
During normal braking, the hydraulic pressure from the hydraulic supply source 2 controlled by the hydraulic supply source hydraulic control means 4 according to the hydraulic pressure output from the auxiliary hydraulic pressure generation means 3 is transmitted by the hydraulic transmission means 5.
_The brake is supplied to each front wheel brake device B _FL , B _FR via the _FL , 5 _FR, and the hydraulic pressure from the hydraulic pressure supply source hydraulic control means 4 is supplied to the respective rear wheel brakes via the hydraulic transmission means 5 _R and the proportional pressure reducing valve 6. It is given to the brake devices B _RL , B _RR . Further, at the time of the braking operation when the hydraulic supply source 2 becomes malfunctioning, the auxiliary hydraulic pressure generating means 3 is used.
Is applied to each of the brake devices _BFL , _BFR , _BRL , and _BRR . In addition, each front wheel brake device B _FL, B _FR individually corresponding flow solenoid valve 7 provided _FL, 7 _FR and the outlet solenoid valves 8 _FL, 8 _FR and the rear wheels brake device B _RL, common to B _RR The anti-lock control can be performed by holding or reducing the brake hydraulic pressure of each brake device B _FL , B _FR , B _RL , B _RR by the inflow solenoid valve 7 _R and the outflow solenoid valve 8 _R provided in the traction control. can be performed each brake device B _FL during non-braking by switching control valve means 9, B _FR, B _RL, increased by the traction control braking oil B _RR.

The hydraulic supply source 2 includes a hydraulic pump 11 for pumping hydraulic oil from the reservoir R, an accumulator 12 connected to the hydraulic pump 11, and a pressure switch 13 for controlling the operation of the hydraulic pump 11.

The auxiliary hydraulic pressure generating means 3 includes a first housing 14 formed in a cylindrical shape with both ends closed. A first working piston 17 is provided in a first cylinder hole 15 provided in the first housing 14.
And a second working piston 18 arranged at a distance in front of the first working piston 17 and a third working piston 19 further arranged at a distance in front of the second working piston 18 can slide. A first hydraulic chamber 16 is formed between the first working piston 17 and the second working piston 18, and a first hydraulic chamber 16 is provided in front of the second working piston 18, that is, between the second working piston 18 and the third working piston 19. A second hydraulic chamber 20 is formed, and a third hydraulic chamber 21 is formed between the front end wall of the first cylinder hole 15 and the third working piston 19.

The first working piston 17 is integrally provided with a piston rod 17a which penetrates a rear end wall of the first cylinder hole 15 in an oil-tight and movably movable manner and protrudes outward, and is connected to the brake pedal 1. The front end of the pressing rod 22 is
It contacts the rear end of 17a. Therefore, brake pedal 1
The first working piston 17 moves forward in the first cylinder hole 15 in response to the braking operation.

On the inner surface of the first cylinder hole 15, a stopper 23 which abuts on the rear end of the second working piston 18 and regulates the retreat limit of the second working piston 18 projects radially inward and projects.
A first return spring 24 for urging the first working piston 17 rearward is contracted between the stopper 23 and the first working piston 17. A second working piston 18 and a third working piston
A second return spring 25 that urges the third operating piston 19 in the direction away from each other is housed in the second hydraulic chamber 20, and a third return spring 26 that urges the third working piston 19 rearward is provided in the first cylinder hole 15. Between the front end wall and the third working piston 19. As a result, the second and third working pistons 18, 19 move forward by the generation of oil pressure in the first hydraulic chamber 16 in accordance with the forward movement of the first working piston 17. However, the set load of the second and third return springs 25 and 26 is controlled by the hydraulic pressure from the hydraulic supply source hydraulic control means 4 which operates according to the hydraulic pressure of the first hydraulic chamber 16 and the opening / closing valve described later.
After the valves 67 _FL , 67 _FR , 67 _R are closed, the second and third working pistons 18, 19 are set to such an extent that they move forward.

The first housing 14 has a first hydraulic chamber 16 connected to a first hydraulic chamber 16.
An output port 27 and a second output port communicating with the second hydraulic chamber 20
28 and a third output port 29 communicating with the third hydraulic chamber 21 are provided, and each hydraulic pressure is set only when the first working piston 17 and the second and third working pistons 18, 19 return to the retreat limit. Communication port for connecting chambers 16, 20, and 21 to reservoir R
30,31,32 are drilled.

The hydraulic supply source hydraulic control means 4 includes a second housing 33,
A spool 34 slidably fitted to the second housing 33,
A reaction piston 35 and a pressing piston 36 are provided.

The second housing 33 has an outer cylindrical portion 37 closed at both ends and an inner cylindrical portion 38 open at both ends coaxially arranged in the outer cylindrical portion 37 and fixed to each other at an intermediate portion thereof. The outer cylinder 37 has an output port 39 and an input port 4 connected to the hydraulic pressure source 2.
0, and release ports 41 communicating with the reservoir R are provided at intervals from the front to the rear (from left to right in FIG. 1). The inner cylinder 38 has a second cylinder hole.
The input port 40 is opened to the inner surface of the second cylinder hole 42. Moreover, an annular concave portion 46 is provided on the outer surface of the spool 34 slidably fitted in the second cylinder hole 42, and the axial length of the annular concave portion 46 is set when the spool 34 is at the rear position. The output port 39 and the release port 41 communicate with each other. When the spool 34 is at the front position, the output port
It is set to communicate between 39 and the input port 40.

At the rear end of the spool 34, a flange portion extending outward in the radial direction
The flange 34a and the second housing 33 are provided.
A spring 48 is contracted between the spool 34 and the spool 34, and the spool 34 is urged rearward by the spring force of the spring 48.

The reaction force piston 35 can be brought into contact with the front end of the spool 34 and is slidably fitted in the second cylinder hole 42 at a position in front of the spool 34. On the other hand, a cap-shaped member 49 is fitted to the front end of the inner cylindrical portion 38, and the cap-shaped member 49 is moved rearward by the spring force of a spring 50 contracted between the inner cylindrical portion 38 and the front end wall of the outer cylindrical portion 37. It is urged toward the side. An output pressure working chamber between the cap-like member 49 and the reaction force piston 35 facing the front surface of the reaction force piston 35
The output pressure working chamber 51 communicates with the output port 39 through a communication hole 52 formed in the cap-shaped member 49.

A spring 54 is contracted between a step portion provided on the inner surface of the second cylinder hole 42 on the front side of the spool 34 and the reaction force piston 35, and the reaction force piston 35 is formed by the spring force of the spring 54.
Is urged forward. Moreover, the set load of the spring 54 is set smaller than the set load of the spring 50, and in a state where no hydraulic pressure is acting on the output pressure action chamber 51,
The front end of the reaction force piston 35 is in contact with the cap-shaped member 49 which is urged by the spring 50 and is in contact with the front end of the inner cylindrical portion 38.

The spool 34 has a communication passage communicating with the release port 41.
56 is bored in the front end face of the spool 34 so as to open.
Therefore, the hydraulic pressure does not act on the rear surface of the reaction force piston 35 and the front surface of the spool 34.

The pressing piston 36 is slidably fitted to an outer cylindrical portion 37 of the second housing 33 on the rear side of the spool 34 so as to abut on the rear end of the spool 34 coaxially.
The rear surface faces an input pressure action chamber 55 defined between the rear end wall and the outer cylinder portion 37.

In this hydraulic supply source hydraulic control means 4, the output pressure action chamber 51
The hydraulic pressure acting on the reaction force piston 35 by the hydraulic pressure toward the rear side and the hydraulic pressure in the input pressure action chamber 55
The spool 34 moves in the axial direction due to the balance with the hydraulic pressure acting on the front side acting on the 36, and the pressure receiving area facing the input pressure action chamber 55 of the pressing piston 36 is the reaction force piston.
The pressure receiving area is set to be larger than the pressure receiving area facing the 35 output pressure action chambers 51. Therefore, the spool 34 can be driven in the axial direction even if the hydraulic pressure introduced into the input pressure action chamber 55 is relatively low.

By the way, the input pressure action chamber of the hydraulic supply source hydraulic control means 4
An oil passage 76 communicating with 55 is connected to a first output port 27 of the auxiliary hydraulic pressure generating means 3 via a proportional pressure reducing valve 77. The proportional pressure reducing valve 77 reduces the oil pressure from the first output port 27 proportionally at a certain value or more to act on the input pressure action chamber 55, and has a conventionally well-known structure. Moreover, an accumulator 78 is connected to the oil passage 76 between the proportional pressure reducing valve 77 and the input pressure action chamber 55.

The accumulator 78 includes an accumulator body 90,
An accumulator piston 92 slidably fitted to the accumulator body 90 while defining a pressure accumulating chamber 91 communicating with the oil passage 76 therebetween, and an accumulator piston 92 in a direction to reduce the volume of the pressure accumulating chamber 91. First and second accumulator springs 93 and 94 are provided in series between the accumulator piston 92 and the accumulator body 90 for energizing.

The accumulator body 90 has a small-diameter hole with one end closed.
A small-diameter hole 95 is provided with a large-diameter hole 97, one end of which is coaxially connected to the other end of the small-diameter hole 95 via a step 96, and the other end of which is closed. The accumulator piston 92 slides into the small-diameter hole 95. It is movably fitted. In addition, a pressure accumulation chamber 91 is defined between one end of the accumulator piston 92 and one closed end of the small-diameter hole 95. In the large-diameter hole 97, a spring receiving member 98 that is in contact with the stepped portion 96 and is restricted from moving toward the one end side is accommodated so as to be movable in the axial direction. The first accumulator spring 93 includes the accumulator piston 92 and the accumulator piston 92. Contracted between the spring receiving members 98,
The second accumulator spring 94 includes a spring receiving member 98 and a large-diameter hole 97.
Is closed between the other end and the closed end. In addition, the set load of the first accumulator spring 93 is increased by the second accumulator spring 94
Is set smaller than the set load. Therefore, when the oil pressure is not acting on the pressure accumulating chamber 91, the spring receiving member 98 is in a position in contact with the step portion 96 by the spring force of the second accumulator spring 94.

Here, the first operation corresponding to the depression operation of the brake pedal 1 is performed.
The hydraulic pressure generated in the first hydraulic chamber 16 by the forward operation of the working piston 17 is reduced by the proportional pressure reducing valve 77,
Although the pressure is accumulated in 78 and acts on the input pressure action chamber 55, the operation of the hydraulic pressure control unit 4 is started so that the hydraulic pressure control unit 4 starts operating before the accumulator 78 operates. The pressure is set lower than the operating pressure of the accumulator 78. That is, the hydraulic supply source hydraulic control means 4
The pressure receiving area facing the input hydraulic pressure chamber 55 of the pressure piston 36 and S ₁ in the pressure receiving area facing the accumulator chamber 91 of the accumulator piston 92 and S _2, the set load of the spring 48 in the hydraulic pressure supply source hydraulic pressure control means 4 f ₁ and then, the set load of the first accumulator spring 93 in the accumulator 78 is taken as f _2, the following equation (1) is set to establish.

f ₁ / S ₁ <f ₂ / S ₂ ... (1) The hydraulic transmission means 5 _FL , 5 _FR , 5 _R are the output port 39 of the hydraulic supply source hydraulic control means 4 and the brake devices B _FL , B _FR , B _RL , _BRR , and the hydraulic transmission means 5 _FL , 5 _FR are provided with a traction control switching control valve means 9 connected to the output port 39 of the hydraulic supply source hydraulic control means 4 and the brake device B _FL. ,
_BFR and the hydraulic transmission means _5R are connected to the output port 39.
And a proportional pressure reducing valve 6 connected to the brake devices B _RL and B _RR . These hydraulic transmission means 5 _FL , 5 _FR , 5 _R
When the hydraulic pressure from the hydraulic supply source 2 is normal, the hydraulic pressure from the hydraulic supply source hydraulic control means 4 is applied to each of the brake devices B _FL , B _FR ,
B _RL and B _RR are transmitted to the hydraulic supply source 2 side when the hydraulic pressure of the hydraulic supply source 2 is abnormally reduced, and the hydraulic oil flows back from the brake devices B _FL , B _FR , B _RL and B _RR to the hydraulic supply source 2 side. Since they have a function of preventing them and have basically the same configuration, the configuration of the hydraulic transmission means _5FL will be described below as a representative.

The hydraulic transmission means 5 _FL is connected to the input hydraulic chamber 58 and the output hydraulic chamber 5.
Free piston 60 moves to cylinder body 6 with both ends facing 9
A spring 62 that is slidably fitted to 1 and biases the free piston 60 toward the input hydraulic chamber 58 is housed and arranged in the output hydraulic chamber 59.

According to such a configuration of the hydraulic pressure transmission means _5FL , it is possible to output a hydraulic pressure according to the hydraulic pressure acting on the input hydraulic chamber 58 from the output hydraulic chamber 59, and to output the hydraulic pressure of the output hydraulic chamber 59 to the input hydraulic chamber 59. It does not flow to the side 58, and the output hydraulic chamber 59 is connected to the brake device _BFL .

That is, the brake devices B _FL , B _FR , B _RL , and B _{RR each} include a cylinder body 63 and a brake piston 64 slidably fitted in the cylinder body 63. The output hydraulic chamber 59 is communicated with the brake hydraulic chamber 65 by moving the brake piston 64 in accordance with the hydraulic pressure acting on the brake hydraulic chamber 65 defined in FIG.

Hydraulic transmission means 5 corresponding to front wheel brake devices B _FL and B _FR
FL, 5 to the input hydraulic pressure chamber 58 of the _FR, the inlet solenoid valve 7 _FL, 7 _FR and the outlet solenoid valves 8 _FL, 8 _FR are respectively connected in parallel, the rear wheel brake device B _RL, corresponding to B _RR the input hydraulic pressure chamber 58 of the hydraulic transmission means 5 _R inflow solenoid valve 7 _R and outlet solenoid valve 8 _R are connected in parallel.

Inlet solenoid valve 7 _FL, 7 _FR, 7 _R is a solenoid valve interrupting during excitation, also spill solenoid valve 8 _FL, 8 _FR, 8 _R is an electromagnetic valve which communicates at excitation. Thus to outlet solenoid valve 8 _FL, 8 _FR, 8 _R is hydraulic transmission means
5 _FL , 5 _FR , 5 _R are interposed between the input hydraulic chamber 58 and the reservoir R, respectively. The inflow solenoid valves 7 _FL and 7 _FR are hydraulic transmission means 5
_FL, 5 _FR is interposed input hydraulic pressure chamber 58 and the output oil passage between 66 _F, the inlet solenoid valve 7 _R are interposed between the hydraulic transmission means 5 inputs the hydraulic chamber 58 and the output oil passage 66 of _{R R.} In addition, each inflow solenoid valve
7 _FL, 7 _FR, 7 in parallel with _R the hydraulic pressure releasing one-way valves 81 _FL, 81 _FR, 81
_R are connected, these one-way valves 81 _FL, 81 _FR, 81 _R are those that allows only the flow of hydraulic fluid from the input hydraulic pressure chamber 58 to the output oil passage 66 _F, 66 _R side.

Such inflow solenoid valves 7 _FL , 7 _FR , 7 _R and outflow solenoid valves 8
_FL, 8 _FR, 8 excitation-demagnetization of _R is intended to be controlled by the control means 80, control means 80, in the normal braking inlet solenoid valve 7 _FL, 7 _FR, 7 _R and outlet solenoid valves 8 _FL, Although 8 _FR and 8 _R are kept demagnetized, during antilock control, the inflow solenoid valves 7 _FL and
7 _FR , 7 _R and the outflow solenoid valves 8 _FL , 8 _FR , 8 _R are both depressurized control state, and the inflow solenoid valves 7 _FL , 7 _FR , 7 _R are excited and the outflow solenoid valves 8 _FL , 8 _FR , a pressure holding state in which degauss 8 _R, inlet solenoid valves 7 _FL, 7 _FR, 7 _R and outlet solenoid valves 8 _FL, 8 _FR, and a pressure increase control while both demagnetized 8 _R can be switched.

Output oil passage 66 _F is the hydraulic pressure supply source hydraulic pressure control means 4 through a normally open electromagnetic valve 9a of the traction control changeover valve means 9
Is the connection to the output port 39, an output oil passage 66 _R is connected directly to the output port 39 of the hydraulic supply source hydraulic pressure control means 4.

Traction control changeover valve means 9, the normally open solenoid valve 9a which is interposed between the output port 39 and the output oil passage 66 _F hydraulic supply source hydraulic pressure control means 4, the hydraulic pressure supply source 2 and the output oil passage 66 _And a normally closed solenoid valve 9b interposed between _F. Excitation and demagnetization of these solenoid valves 9a and 9b are also controlled by the control means 80, and the control means 80 demagnetizes and opens the solenoid valve 9a and demagnetizes the solenoid valve 9b in a normal state. During traction control in a non-braking state, the solenoid valve 9a is excited to close and the solenoid valve 9b is closed.
Excite and open the valve. Further, the control means 80, the excitation of the solenoid valve 9a pressure boosting i.e. inlet solenoid valve 7 _FL in anti-lock control state, 7 _FR, 7 _R and outlet solenoid valves 8 _FL, the 8 _FR, 8 _R are both state of demagnetization -Switching control of demagnetization is also possible.

The solenoid valve 9b in the traction control switching control valve means 9 is connected to the hydraulic pressure source 2 through a constant differential pressure reducing valve 83. Therefore, when the solenoid valve 9b is opened, the hydraulic
Decompressed output oil passage 66 _F hydraulic oil by the pressure reducing valve 83 from
Will be supplied in between.

Proportional pressure reducing valve 6, which has a well-known structure, the hydraulic transmitting means 5 _R of proportionally reduced pressure to the rear wheel brake device the hydraulic pressure output from the output hydraulic pressure chamber 59 at a certain value or more B
_RL and B _RR act to act on the brake hydraulic chamber 65.

The second output port 28 of the auxiliary hydraulic pressure generating means 3
The third output port 29 of the auxiliary hydraulic pressure generating means 3 is connected between the proportional pressure reducing valve 6 and the hydraulic pressure transmitting means 5 _R via _R ,
It is connected between the left front wheel brake device B _FL and the hydraulic transmission means 5 _FL via the 67 _FL , and connected between the right rear wheel brake device B _FR and the hydraulic transmission means 5 _FR via the open / close valve 67 _FR. You. Off valves 67 _FL, 67 _FR, 67 _R are those having the same configuration, will be described only to the following configuration of the on-off valve 67 _FL.

On-off valve 67 _FL is a cylindrical on-off valve body with both ends closed
A valve hole 69 formed in one end wall of the on-off valve body 68 while communicating with the output hydraulic chamber 59 of the hydraulic transmission means 5 _FL ;
An opening / closing piston 72 which has a valve body 70 at one end capable of closing the 69 and is slidably fitted to the opening / closing valve body 68 with the other end facing the pilot chamber 71, and the opening / closing piston 72 is connected to the pilot chamber. A spring 73 is provided between the opening / closing valve body 68 and the opening / closing piston 72 so as to urge it toward the 71 side.

A valve chamber 74 that can communicate with the valve hole 69 is defined between the one end wall of the opening / closing valve body 68 and the opening / closing piston 72, and a spring is formed in the valve chamber 74.
73 is stored. The opening / closing valve body 68 is provided with an inlet port 75 communicating with the valve chamber 74 and communicating with the third output port 29.

According to the opening / closing valve _67FL , when the oil pressure in the pilot chamber 71 is lower than a predetermined value, the opening / closing piston 72 moves to the pilot chamber 71 side until the valve body 70 opens the valve hole 69 and opens. When the oil pressure in the pilot chamber 71 becomes equal to or higher than the predetermined value, the opening / closing piston 72 moves so as to close the valve hole 69 with the valve body 70 and closes the valve.

Branched from the output oil passage 66 _F branch oil passage 84 _FL is communicated to the pilot chamber 71. Therefore, when the oil pressure in the branch oil passage _84FL, that is, the pilot chamber 71 is high, the on-off valve _67FL closes to shut off the connection between the third output port 29 and the brake device _BFL , and the oil pressure in the branch oil passage _84FL decreases. The on-off valve _67FL is opened to allow _{communication} between the third output port 29 and the brake device BFL.

The on-off valve 67 _FR closes when the oil pressure of the branch oil passage 84 _FR branched from the output oil passage 66 _F is high, shuts off the third output port 29 and the brake device B _FR , and the branch oil passage 84 _FR When the hydraulic pressure is low, the valve is opened to communicate between the third output port 29 and the brake device _BFR . Further, the on-off valve 67 _R is connected to the output oil passage 66.
_The valve closes when the oil pressure in the branch oil passage 84 _R branched from _R is high,
As a result, the connection between the second output port 28 of the auxiliary hydraulic pressure generation means 3 and the brake devices B _RL and B _RR is cut off, and the branch oil passage 84 _R
The second output port 28 and the brake device B _RL, between B _RR is communicated with the valve opening pressure is lowered and opening and closing valve 67 _R is.

In the output oil passage 66 _F, 85 _F first one-way valve is interposed in the branch oil passage 84 _FL, 84 _FR hydraulic transmission means 5 _FL than bifurcation, 5 _FR side, branching at an output oil passage 66 _R oil passage 84 _R hydraulic transmission means 5 to the _R-side first one-way valve 85 _R than bifurcation is interposed.
These first one-way valves 85 _F and 85 _R are provided with a first preset one-way valve.
Valve opening pressure [Delta] P ₁ or more depending on the differential pressure is to permit only a flow of hydraulic oil from the open output port 39 side to the hydraulic transmitting means 5 _FL, 5 _FR, 5 _R side.

Also the the first one-way valve 85 _F, 85 _R second one-way valve 86 _F, 8
6 _R are connected in parallel. These second one-way valve 86 _F, 86 _R
Opens the valve in accordance with the differential pressure equal to or greater than the preset _second valve opening pressure ΔP ₂ to allow only the flow of hydraulic oil from the hydraulic transmission means 5 _FL , 5 _FR , 5 _R to the output port 39. The second valve opening pressure ΔP ₂ is set to be smaller than the first valve opening pressure ΔP ₁ (ΔP ₂ <ΔP ₁ ).

Next, the operation of this embodiment will be described. First, assuming a normal braking operation in a state where the hydraulic supply 2 is operating normally, the inflow solenoid valves 7 _FL , 7 _FR , 7 _R and the outflow solenoid valves 7 _FL , 7 _FR , 7 _R
8 _FL , 8 _FR , 8 _R are in a demagnetized state (the state shown in FIG. 1), and both solenoid valves 9 a, 9 b of the traction control switching control valve means 9.
Are also in the demagnetized state (the state shown in FIG. 1). Therefore, the output port 39 of the hydraulic supply source oil pressure control means 4 is connected to the output oil passages 66 _F and 66.
Communicates with the _R, one output oil passage 66 _F is flowing the solenoid valve 7 _FL, 7 _FR
Through the input hydraulic chamber 58 of the hydraulic transmission means 5 _FL and 5 _FR , and the other output oil passage 66 _R is connected to the input hydraulic chamber 58 of the hydraulic transmission means 5 _R via the inflow solenoid valve 7 _R. They are in communication.

When the brake pedal 1 is depressed in such a state, the first operating piston 17 of the auxiliary hydraulic pressure generating means 3 operates forward, and the hydraulic pressure generated in the first hydraulic chamber 16 is reduced by the proportional pressure reducing valve 77 to control the hydraulic supply source hydraulic pressure. It acts on the input pressure action chamber 55 of the means 4 and on the accumulator chamber 91 of the accumulator 78. At this time, the hydraulic pressure control unit 4 is set to start operating earlier than the accumulator 78. That is, the pressure-receiving area S ₁ facing the input hydraulic pressure chamber 55 of the pressure piston 36 in the hydraulic supply source hydraulic pressure control means 4, the pressure receiving area S ₂ which faces the accumulator chamber 91 of the accumulator piston 92, the hydraulic pressure supply source hydraulic pressure control means 4
Set of the first accumulator spring 93 in the set load f _1, and the accumulator 78 of the spring 48 in the load f ₂
Is set such that the inequality shown in the above-mentioned equation (1) is satisfied.

As a result, in the hydraulic supply source hydraulic control means 4, the pressing piston 36 moves forward before the accumulator 78 performs the pressure accumulation operation,
The spool 34 whose rear end is in contact with the pressing piston 36 is driven forward. Accumulator like this
By starting the operation of the hydraulic pressure control means 4 prior to the pressure accumulating operation of 78, it is possible to avoid the generation of useless reaction force during the braking operation, to prevent the loss of the pedaling force of the brake pedal 1, and to improve the responsiveness. Can be.

When the spool 34 moves forward by a certain distance in accordance with the advance of the pressing piston 36, the output port 39 communicates with the input port 40, and the output hydraulic pressure from the output port 39 communicating with the pressing supply source 2 rapidly increases. . Thus was first one-way valve 85 at the output oil passage 66 _F, 66 _R are _F, 85 _R of the differential pressure across the first valve opening pressure [Delta] P ₁
Before reaching the pressure, the on-off valves 67 _FL , 67 _FR , 67 _R are first closed in accordance with the increase in the oil pressure of the branch oil passages 84 _FL , 84 _FR , 84 _R , and then the differential pressure is equal to or greater than the first valve opening pressure ΔP ₁ The first one-way valve
85 _F and 85 _R open. As a result, the hydraulic pressure from the output port 39 acts on the input hydraulic chamber 58 of the hydraulic transmission means 5 _FL , 5 _FR via the output oil passage 66 _F and the inflow solenoid valves 7 _FL , 7 _FR to cause the brake devices B _FL , B _FR in can be obtained braking pressure, also acts on the input hydraulic pressure chamber 58 of the hydraulic oil pressure transmitting means 5 _R through the output oil passage 66 _R and the inlet solenoid valve 7 _R from the output port 39, the hydraulic transmission means The hydraulic pressure output from the 5 _R output hydraulic pressure chamber 59 is reduced in pressure by the proportional pressure reducing valve 6 and applied to the rear wheel brake devices B _RL and B _RR . Therefore, during braking, the hydraulic transmission means 5 _FL , 5 _FR , 5 _R
The opening and closing valves 67 _FL , 67 _FR , 67 _R are surely closed before the operation of, and the responsiveness is improved by increasing the braking pressure simultaneously with the operation of the hydraulic transmission means 5 _FL , 5 _FR , 5 _R. it can.

In addition, since the output oil pressure from the output port 39 increases rapidly, the play gaps of the respective brake devices B _FL , B _FR , B _RL , B _RR are removed by supplying a relatively high oil pressure, and the respective brake devices are removed. The initial operation of the brake piston 64 of B _FL , B _FR , B _RL , B _RR becomes smooth.

Due to the communication of the output port 39 with the input port 40, the hydraulic pressure of the output pressure working chamber 51 also increases, and the reaction force piston 35 is driven rearward to abut the front end of the spool 34, whereby the spool 38 retreats. The output port 39 is cut off from the input port 40. Further, as the hydraulic pressure in the first hydraulic chamber 16 increases by depressing the brake pedal 1, the spool
34 advances again, and the output port 39 communicates with the input port 40. In this way, in response to the braking operation of the brake pedal 1, the spool 34 reciprocates between the front position where the output port 39 communicates with the input port 40 and the rear position where the output port 39 is disconnected from the input port 40. Accordingly, the hydraulic pressure of the hydraulic pressure supply source 2 is controlled according to the braking operation amount of the brake pedal 1 and output from the output port 39.

In this manner, the hydraulic pressure from the hydraulic supply source 2 can be controlled by the hydraulic supply source hydraulic control means 4 according to the braking operation amount and applied to each of the brake devices B _FL , B _FR , B _RL , and B _RR . In the hydraulic transmission means 5 _FL , 5 _FR , 5 _R , the free piston 60 separates each brake device B _FL , B _FR , B _RL , B _RR from the hydraulic circuit from the input hydraulic chamber 58 to the hydraulic supply 2. Therefore, the gas that may be mixed into the hydraulic oil in the hydraulic supply source 2 does not adversely affect the brake devices B _FL , B _FR , B _RL , and B _RR .

At this time, the second hydraulic pressure in the first hydraulic chamber 16 in the auxiliary hydraulic pressure generation means 3 is changed according to the depression operation of the brake pedal 1.
When the forward hydraulic pressure of the working piston 18 exceeds the set load of the second and third return springs 25 and 26, the hydraulic pressure of the second and third hydraulic chambers 20 and 21 increases due to volume contraction.
Since 7 _FL, 67 _FR, 67 _R is closed, hydraulic pressure is the brake device B _FL of the hydraulic chambers 20, 21, B _FR, B _RL, never acts on B _RR.

At the time of this braking, the braking force of the left and right rear wheels needs to be lower than that of the left and right front wheels, and the braking force of the left and right rear wheels is reduced by reducing the hydraulic pressure from the hydraulic pressure supply source hydraulic control means 4 by the proportional pressure reducing valve 6. It is lower at a fixed ratio than the left and right front wheels.

Further, since the oil pressure in the first oil pressure chamber 16 acts on the input pressure action chamber 55 via the proportional pressure reducing valve 77, the oil pressure acting on the input pressure action chamber 55 and the accumulator 78 is kept low, and the oil pressure supply source oil pressure control means 4 This can contribute to reducing the load on the accumulator 78. In addition, when the brake pedal 1 is idled several times, the hydraulic pressure in the first hydraulic chamber 16 is reduced by the proportional pressure reducing valve 77 and applied to the input pressure action chamber 55,
The frequency of hydraulic pressure increase after the hydraulic pressure control unit 4 can be reduced, the amount of hydraulic oil circulated can be reduced to reduce wasteful consumption of hydraulic oil, and the free piston 60 in the hydraulic transmission units 5 _{FL to} 5 _R can be controlled. The operation frequency can be suppressed to contribute to the improvement of durability.

Further, by accumulating the hydraulic pressure from the first hydraulic chamber 16 with the accumulator 78, the pedal stroke of the brake pedal 1 can be ensured, so that the hydraulic supply source hydraulic control means 4 has a configuration for ensuring the pedal stroke. This is unnecessary, and the hydraulic supply hydraulic pressure control means 4 can be reduced in size. In addition, it is possible to prevent the sudden reaction force from directly acting on the brake pedal 1 due to the damper action by the accumulator 78 when the sudden reaction force acts.

During such braking, when the pedaling force of the brake pedal 1 becomes excessive and the wheels are about to lock, the inflow solenoid valves 7 _FL , 7 _FR , 7
7 _R is excited, and the output oil passage 66 _F and the hydraulic transmission means 5 _FL , 5 _FR
During, as well as to block between the output oil passage 66 _R and the hydraulic transmission means 5 _R. This suppresses an increase in the braking force to avoid the wheels from being locked. If the wheel is still about to enter the locked state, the corresponding outflow solenoid valve
8 _FL, the 8 _FR, 8 hydraulic transmission means by energizing the _R 5 _FL to 5 _R of the input hydraulic pressure chamber 58 communicates with the reservoir R, it is possible to eliminate the locking tendency of the wheels by lowering the braking pressure.

After the lock tendency is eliminated, the inflow solenoid valves 7 _FL , 7 _FR , 7 _R
The demagnetizing the outflow solenoid valve 8 _FL, 8 _FR, 8 _R together demagnetized.
Thereby increasing the braking pressure hydraulic allowed to act again the hydraulic transmitting means 5 _FL, 5 _FR, 5 _R from the hydraulic supply source hydraulic pressure control means 4 output ports 39.

By controlling the operation of the solenoid valve 9a in the traction control switching valve means 9 at the time of pressure increase in such an anti-lock control state, the anti-lock control of both front wheels can be performed more precisely. That is, by intermittently closing the solenoid valve 9a, it is possible to prevent the oil pressure from the output port 39 from acting on each of the inflow solenoid valves _7FL , _7FR abruptly, and to moderate the increase in oil pressure. Also, when anti-lock control is performed on the front wheels that are in contact with the road surface with a low friction coefficient while the friction coefficients of the ground road surfaces of the left and right front wheels are different, braking with the front wheels that are in contact with the road surface with a high friction coefficient It is also possible to suppress the rise in pressure by the intermittent closing operation of the solenoid valve 9a, and to gently suppress the generation of the yaw moment of the vehicle body.

It is assumed that a high hydraulic pressure cannot be obtained from the hydraulic pressure supply source 2 due to a failure of the hydraulic pump 11 or the like during the braking. In this case, the on-off valves 67 _FL , 67 _FR , 67 _R are opened by the decrease in the oil pressure of each of the branch oil passages 84 _FL , 84 _FR , 84 _R according to the decrease in the oil pressure from the output port 39 of the oil pressure supply source oil pressure control means 4. I do. Therefore, the braking hydraulic pressure generated in the second and third hydraulic chambers 20 and 21 of the auxiliary hydraulic pressure generating means 3 directly acts on each of the brake devices B _{FL to} B _RR , and the braking force can be secured. .

At this time, the hydraulic transmission means 5 _{FL to} 5 _R are connected to the respective brake devices B _FL to
The brake pressure of each of the brake devices B _{FL to} B _RR does not escape to the hydraulic pressure control unit 4 side because it is interposed between the B _RR and the hydraulic pressure control unit 4.

During non-braking after braking operation ends, the branch oil passage 84 _FL in accordance with the output oil pressure of the output port 39, 84 _FR, 84 first closing valve 67 _FL by oil pressure of the _R, 67 _FR, 67 _R is opened. Then, the second one-way valve 86 _F, 86 _R second one-way valve 86 _F, 86 _R is opened in response to differential pressure across is the second valve opening pressure [Delta] P ₂ or more, the hydraulic transmitting means The input hydraulic chambers 58 at 5 _{FL to} 5 _R communicate with the reservoir R via the hydraulic pressure control unit 4. Thus it is possible to breathe the output hydraulic pressure chamber 59 in response to movement of the input hydraulic pressure chamber 58 side of the free piston 60 in the hydraulic transmitting means 5 _FL to 5 _R. Moreover, the hydraulic pressure of the input hydraulic chamber 58 in each of the hydraulic transmission means 5 _{FL to} 5 _R can be released to the output oil passages 66 _F , 66 _R via the hydraulic release one-way valves 81 _FL , 81 _FR , 81 _R. Even if the flow resistance in the inflow solenoid valves 7 _FL , 7 _FR , 7 _R is large, the hydraulic pressure in the input hydraulic chamber 58 is quickly released, and the free piston
60 can be quickly returned to its original position.

By the way, it is conceivable that the hydraulic pressure in the input hydraulic chamber 58 increases due to the temperature increase in each of the hydraulic pressure transmission means 5 _FL , 5 _FR , 5 _R during non-braking, in which case the braking pressure is applied if the hydraulic pressure cannot be released. become. However, the second one-way valve 86
_F, 86 second valve opening pressure [Delta] P ₂ of _R is less than the first valve opening pressure [Delta] P ₁ of the first one-way valve 85 _F, 85 _R, since it is set to a relatively small value, the input hydraulic pressure chamber The valve opens according to the oil pressure increase of 58,
Hydraulic oil corresponding to the increased hydraulic pressure can be released.

Furthermore, during non-braking, the driving force of the engine becomes excessive,
When the drive wheels are about to slip excessively, the two solenoid valves 9a and 9b of the traction control switching control valve means 9 are controlled by the control means 8
Excited by 0. As a result, the hydraulic pressure from the hydraulic supply source 2 acts on the input hydraulic chamber 58 of the hydraulic transmission means 5 _FL , 5 _FR , and braking force is generated by the brake devices B _FL , B _FR of the left and right front wheels, which are drive wheels, resulting in excessive slip. Is avoided. After this,
As in the above-described anti-lock control, the inflow solenoid valves 7 _FL and 7
_The braking force can be controlled by the excitation and demagnetization control of the _FR and the outflow solenoid valves 8 _FL and 8 _FR .

Moreover, the output oil pressure of the hydraulic supply source 2 is set to be considerably large.
Thus, the traction control is not performed by an excessive oil pressure.
Therefore, control responsiveness does not decrease or become smooth.

 FIG. 2 shows another embodiment of the present invention.

In the middle of the output oil passage 66 _F, 66 _R, the casing 100 is interposed. Inside the casing 100, the portions 66 _Fa , 66 of the output oil passages 66 _F , 66 _{R on the side} of the hydraulic pressure source control unit 4 (see FIG. 1).
_Ra and hydraulic transmission means 5 _FL , 5 _FR , 5 _R (see Fig. 1) side
A storage chamber 101 for opening 66 _Fb and 66 _Rb at both end walls in the axial direction is provided. In the storage chamber 101, a hydraulic supply source hydraulic control of the output oil passages 66 _F and 66 _R is provided between the storage chamber 101 and an inner surface of the storage chamber 101. Means 4 side part 66 _Fa ,
A sleeve 103 forming an annular outer peripheral passage 102 connecting the 66 _Ra and the hydraulic transmission means 5 _FL , 5 _FR , 5 _R side portions 66 _Fb , 66 _Rb is housed,
Fixed. The sleeve 103 has the output oil passages 66 _F and 66 _R.
Through- hole 110 connecting the hydraulic supply source hydraulic control means 4 side part 66 _Fa , 66 _Ra and the hydraulic transmission means 5 _FL , 5 _FR , 5 _R side part 66 _Fb , 66 _Rb
Is drilled.

A first one-way valve 104 is provided in the middle of the through hole 110.
The first one-way valve 104 includes a spherical valve body 106 housed in a valve chamber 105 provided in the middle of the through hole 110, and a spring 107 for urging the valve body 106 in a valve closing direction. Also sleeve 1
On the outer surface of 03, a cup seal 108 as a second one-way valve is provided.
Is fitted to open and close the outer peripheral passage 102.

According to this embodiment, the same effect as that of the embodiment of FIG. 1 can be obtained, and the first one-way valve 104 and the cup seal 108 (second one-way valve) can be made compact. Can be.

C. Effects of the Invention As described above, according to the present invention, during normal braking in which the hydraulic pressure of the hydraulic supply source is normal, the hydraulic pressure is output from the output port of the hydraulic supply source hydraulic control means that operates according to the braking operation. In addition, it is possible to apply a hydraulic pressure to the hydraulic pressure transmission means via the first one-way valve and to apply a braking pressure to the brake device by closing the on-off valve. Also, when the hydraulic pressure of the hydraulic supply source drops abnormally, the on-off valve is opened, and the hydraulic pressure output from the hydraulic chamber of the auxiliary hydraulic pressure generating means in accordance with the brake operation amount of the brake pedal acts on the brake device to perform braking. Pressure can be secured. In addition, when the on-off valve is opened, the hydraulic pressure of the brake device is prevented from escaping to the hydraulic supply source side by the hydraulic transmission means. Further, when shifting from the braking operation state to the non-braking operation state, the operation of the second one-way valve ensures that the on-off valve is opened earlier than the operation of the hydraulic transmission means, thereby allowing the output hydraulic chamber in the hydraulic transmission means to breathe. The free piston of the hydraulic transmission means can be returned to its original position.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing one embodiment of the present invention, and FIG. 2 is a sectional view showing first and second one-way valves in another embodiment of the present invention. 1 ... Brake pedal, 2 ... Hydraulic supply source, 3 ... Auxiliary hydraulic pressure generating means, 4 ... Hydraulic supply source hydraulic control means, 5 _FL , 5
_FR , 5 _R …… Hydraulic transmission means, 14 …… Housing, 16 …… Hydraulic chamber, 17 …… Working piston, 39 …… Output port, 40 ……
Input port, 58 …… Input hydraulic chamber, 59 …… Output hydraulic chamber, 60
…… Free piston, 61 …… Cylinder body, 66 _F , 66 _F ……
Output oil passage, 67 _FL , 67 _FR , 67 _R …… On-off valve, 84 _FL , 84 _FR , 84 _R …
... branch oil _{passage, 85 F, 85 R, 104} ...... first one-way valve, 86 _F, 86 _R ...
... second one-way valve, 108 ... cup seal as second one-way valve, B _FL , B _FR , B _RL , B _RR ... brake device

Continuation of front page (72) Inventor Kazutoshi Tajima 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Technical Research Institute Co., Ltd. (56) References JP-A-62-23856 (JP, A) JP-A-63-63 40271 (JP, A)

Claims (1)

(57) [Claims] An input port connected to a hydraulic pressure supply source and an output port connected to a brake device, wherein input hydraulic pressure of the input port is controlled in accordance with a braking operation amount and output from the output port. A hydraulic chamber is formed in a housing with a front end face of a working piston connected to and linked to a brake pedal to move forward in accordance with a braking operation in a braking hydraulic control apparatus including a hydraulic supply source hydraulic control means. Auxiliary hydraulic pressure generating means; and an input hydraulic chamber that can communicate with an output oil path connected to the output port of the hydraulic supply source hydraulic control means and an output hydraulic chamber that communicates with the brake device. A hydraulic transmission means slidably fitted; interposed between the hydraulic transmission means and the brake device and a hydraulic chamber of the auxiliary hydraulic transmission means, branched from the output oil passage; An on-off valve that shuts off in response to an increase in the oil pressure in the branch oil passage; and a hydraulic oil that is interposed in the output oil passage closer to the hydraulic transmission means than the branch portion of the branch oil passage, and is connected to the hydraulic transmission means from the output port. A first one-way valve that permits only the flow of air through the first one-way valve; is opened in parallel with the first one-way valve at a differential pressure equal to or higher than a preset valve-opening pressure to move from the hydraulic transmission means side to the output port side And a second one-way valve that permits only the flow of hydraulic oil.