JPH0676046B2 - Hydro booster with anti-skidding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a hydrobooster in which an antiskid device is integrally incorporated.

[Conventional technology]

Conventionally, as a device used for a brake system for vehicle braking, a hydro booster as a booster mechanism, an anti-skid control device for preventing wheel lock occurrence during braking, etc. have been proposed variously. Are generally configured as individual devices.

However, since these are built into one system called the vehicle brake, if these are combined well into an integrated unit, the workability of assembling into the vehicle will be advantageous, and further structural, If a functional improvement is achieved, its usefulness will be extremely large.

By the way, in such an integrated device, the operation of the anti-skid device, whose operation is extremely rarely performed, is guaranteed, and even when the anti-skid control system is defective, it does not adversely affect the normal braking system. Although it is important to take a configuration, a hydrobooster with an antiskid device having such a configuration has not been provided so far.

[Problems to be Solved by the Invention]

The present invention has been made from such a viewpoint, and an object thereof is to operate an apparatus for anti-skid control, which rarely operates, during normal brake operation so that there is no risk of rusting of the apparatus. This is to improve the operational reliability.

Another object of the present invention is to provide a hydro-booster with an anti-skid device which prevents the failure of the anti-skid control system from normally affecting the brake system when the anti-skid control system is defective.

[Means for Solving the Problems]

Therefore, the feature of the hydro booster with the anti-skid device according to the present invention, which is made to realize such an object, is that the hydraulic pressure level introduced from the pressure accumulating source is determined depending on the stepping force of the brake pedal. A main cylinder device incorporating a pedal response device and a master cylinder type control hydraulic pressure generation mechanism that generates a control hydraulic pressure depending on the hydraulic pressure effect of the introduced hydraulic pressure, and one end of the main cylinder device into the control hydraulic chamber into which the control hydraulic pressure is introduced. A movable power piston that faces the brake oil chamber and has the other end exposed to the brake fluid chamber and communicates with the brake fluid chamber by the hydraulic action of the control fluid chamber to generate a brake hydraulic pressure in the brake fluid chamber, and the movable power piston In contrast to the sub-cylinder device that has an anti-skid control oil chamber that applies hydraulic pressure in the return movement direction, and the hydraulic pressure introduced to the pedal response device. Interposed in path provided so as to convey to the anti-skid control oil chamber of Kifuku cylinder device,
In a hydro booster with an anti-skid device including an anti-skid control solenoid valve device that supplies and discharges pressure oil to and from the anti-skid control oil chamber by using an anti-skid signal as an input, the auxiliary cylinder device includes the movable power A returning piston that moves in association with the movement of the piston when the brake hydraulic pressure is generated is provided so as to be engaged and carried when the movement of the movable power piston from the initial position occurs for a certain length or more, The hydraulic action force for returning the movable power piston from the anti-skid control oil chamber is transmitted to the movable power piston via the returning piston.

[Action]

In the above configuration, the hydraulic working force from the anti-skid oil chamber acting on the power piston of the sub-cylinder device is transmitted to the power piston through the returning piston in the initial stroke of the power piston. The return piston continues to be stationary at the initial position (while the stroke is a fixed length l), and then the return piston is entrained in association with the operation stroke of the power piston exceeding the fixed length l. This is because the hydraulic action force (that is, the piston return force) from the antiskid oil chamber does not act on the power piston due to the disengagement of both pistons during the fixed length l. As a result, the forced return of the power piston during anti-skid control, and thus the return operation of each operating portion in the main cylinder device to the initial side, can be arbitrarily determined by setting the constant length l. The advantage is that the return amount of the brake pedal during skid control can be set in consideration of ensuring the re-depression stroke amount in consideration of the failure of one system of the two-system brake hydraulic system.

According to the present invention having the above-described structure, the device for anti-skid control, which rarely operates, can be operated during normal brake operation, and the risk of rusting of the device can be eliminated.

Moreover, since the anti-skid control system is independent of the normal braking system, the failure does not adversely affect the normal braking system.

〔Example〕

 The present invention will be described below based on embodiments shown in the drawings.

The apparatus of the present embodiment includes a main cylinder apparatus 1 in which a hydro booster type pedal response apparatus and a master cylinder type control hydraulic pressure generation apparatus are housed in concentric stepped cylinders I and II, and a control oil chamber F of the main cylinder apparatus. A sub-cylinder device 100 having a control oil chamber H connected to the sub-cylinder device and an anti-skid control solenoid valve device 200 for supplying and discharging the hydraulic pressure of the anti-skid oil chamber C of the sub-cylinder device are combined. Illustration of the sub-cylinder device hydraulically linked to the control oil chamber G of the other system of the cylinder type control hydraulic pressure generator is omitted. That is, the device of this example is
The brake hydraulic system has two independent systems, and an independent sub-cylinder device and an anti-skid control solenoid valve device are provided respectively connected to the two control oil chambers F and G of the tandem master cylinder device.

First, the individual configuration of each of these devices will be described.

Main Cylinder Device 1 First, the pedal response device in the cylinder I will be described.
This is because the control piston 3 having an appropriate flow passage is
It is slidably engaged with the first cylinder I and is biased by the return spring 5 toward the rear end (right end in the drawing) opening side. A flow path switching piston 4 is slidably fitted in the axial cylinder 3a of the control piston 3, and its rear end portion is engaged with a brake pedal via a ball joint (not shown).

The pedal response device constituted by the relationship between the control piston 3 and the switching piston 4 is substantially the same as the known hydro booster, and is in the state shown in the drawing when the brake is not applied, and the introduction oil chamber B and the hydraulic pressure release oil chamber are shown. When E is communicated via the passage 4a and the switching piston 4 is embedded relatively to the control piston 3 by the brake pedal depression force, the communication between the oil chambers B to E is closed and the pressure source side is closed. The oil chamber A and the oil chamber B are communicated with each other. The oil chamber A is connected to the pressure accumulator 6.

In the above description, when the oil pressure is introduced into the oil chamber B by the communication between the oil chambers A and B, the oil pressure against the stepping force of the brake pedal acts on the tip of the switching piston 4,
This acts as a reaction force against the pedal depression force. Therefore, the hydraulic pressure proportional to the stepping force is transmitted from the oil chamber A to the oil chamber B, and in this state, the communication between the oil chambers A, B and E is cut off.

When the oil pressure is introduced into the oil chamber B, a forward force (moving force to the left in the figure) against the spring force of the return spring 5 is given to the control piston 3 by the action of this introduced oil pressure.

Reference numeral 7 is a return spring for the switching piston.

Next, the configuration of the tandem master shilling type control hydraulic pressure generator in the second cylinder II will be described.

The same device of this example accommodates a first and a second hydraulic pistons 10, 11 in a cylinder II and a pair of return springs 12, 13 for biasing them to an initial position, and a rear end of the first hydraulic piston 10 ( The control piston 3 is interlockingly engaged with the right end of the figure, and the moving force of the control piston 3 is received as an external input to generate a control hydraulic pressure in the pair of control oil chambers F and G. , The hydraulic pressure in the pair of control oil chambers F and G is the second
It is balanced by the balancing action of the hydraulic piston 11.

In addition, 14 is a guide ring of the first hydraulic piston 10, 15 and 16
Is a one-way seal mechanism provided so that oil can be supplied from the reservoirs 17, 18 to the control oil chambers F, G.

The main cylinder device 1 described above introduces a predetermined hydraulic pressure into the introduction oil chamber B according to the stepping force to the brake pedal, and generates the control oil pressure in the control oil chambers F and G according to the value of this introduction hydraulic pressure. Therefore, the boosting ratio is determined according to the pressure receiving area that determines the magnitude of the hydraulic reaction force acting on the switching piston 4.

Sub-cylinder device 100 The sub-cylinder device of this example has a power piston 103 across two concentrically-spaced opposed cylinders 101, 102 that are hydraulically partitioned.
The power piston 103 has a rear end (left end in the drawing) facing the control oil chamber H (communication with the control oil chamber F of the main cylinder device), and a front end (left end in the drawing) of the hydraulic piston 104.
Is engaged with. The hydraulic piston 104 faces the brake fluid chamber I (communicating with the wheel cylinder [W / C] of the brake device) at its front end, and the built-in open / close valve 105 opens the brake fluid chamber at all times (at rest). The pressure oil of I is drained to the reservoir 106, and the hydraulic piston 104 becomes the power piston.
When it is moved by 103, the built-in on-off valve 105 is closed to generate the brake oil pressure in the brake oil chamber I. The on-off valve 105 is of a type in which a ball valve element is separated from a valve seat by a locking rod 107 in the internal flow path of the hydraulic piston 104. Note that 108 and 109 are return springs for the power piston and hydraulic piston, respectively, and 110 is a set spring for the locking rod.

Further, the shaft portion of the power piston 103 of the sub-cylinder device 100 of the present example faces the large diameter cylinder 112, and the return piston 111 is accommodated by sliding on the large diameter cylinder 112. The return piston 111 is biased to the initial position shown by the return spring 108 being engaged, and in this state, the return piston 111 opposes the power piston 103 in the initial position stationary state with a clearance of a constant length l in the axial direction. There is. Therefore, the return piston 111 remains stationary until the power piston moves to the left by the hydraulic pressure of the control oil chamber H and the movement reaches the constant length l, but when the power piston moves beyond the constant length l. Is associated with the power piston and is entrained to the left in the figure.

An anti-skid oil chamber C for pushing the returning piston 111 back toward the initial position is provided in the large-diameter cylinder 112 of the sub-cylinder device 100. This anti-skid oil chamber C is connected to the introduction oil chamber B of the pedal response device via the anti-skid solenoid valve device 200 described below, and when the hydraulic pressure is introduced, the return piston 111 is pushed back to the initial position shown in the figure. Therefore, the power piston 103 associated therewith is also pushed back to the position moved by l from the initial position.

In the sub-cylinder device 100 having the above configuration, the power piston 103 moves depending on the hydraulic pressure value transmitted to the control oil chamber H during normal braking, which causes the hydraulic piston 1 to move.
The movement of 04, and accordingly the closing of the on-off valve 105 and the generation of the brake hydraulic pressure in the brake fluid chamber I are performed. At this time, no hydraulic pressure is transmitted to the anti-skid oil chamber C.

During the anti-skid control, the hydraulic pressure is transmitted to the anti-skid oil chamber C, so that the power piston 103 is returned to the position of the maximum l in the control oil chamber H direction via the returning piston 111, and therefore the return movement of the hydraulic piston 104 is prevented. As a result, the brake oil pressure is reduced, and the oil pressure in the anti-skid oil chamber C is released to the reservoir 106 via the pressure reducing valve 206, whereby the brake oil pressure is (re) pressurized.
The power piston 103 again receives the hydraulic action of the control oil chamber H and moves to the left in the drawing, and the hydraulic pressure of the hydraulic piston 104 moves in the same direction to pressurize the brake hydraulic pressure. That is, decompression, pressurization, and holding of the brake hydraulic pressure are given depending on the hydraulic pressure state of the anti-skidding oil chamber C based on the switching of the opening / closing of the solenoid valve.

Anti-skid control solenoid valve device 200 This device of this example is a normally-closed solenoid valve (hereinafter PSV) installed in the middle of a connection path 201 between the introduction oil chamber B of the pedal response device and the anti-skid oil chamber C. 204), a hold valve 205, which is a normally open solenoid valve provided in a path 202 for draining the pressure oil in the anti-skid oil chamber C to the reservoir 106, and an opening / closing valve of the sub cylinder device. It is composed of a combination of a pressure reducing valve 206 which is a normally-open solenoid valve provided in a path 203 for extracting pressure oil to the reservoir 106, and a check valve 207 is further provided in the path 201. Although shown as a symbol of the reservoir 106, this corresponds to the reservoir 19 integrated with the main cylinder device.

Each solenoid valve of the solenoid valve device 200 as described above is subjected to open / close switching control as shown in the following table, for example, by inputting each antiskid signal for depressurizing, pressurizing, and holding the brake hydraulic pressure for antiskid control. .

The anti-skid signal for operating the solenoid valve device described above uses a known anti-skid control circuit that detects and outputs control information for reducing, pressurizing, and holding the brake hydraulic pressure depending on the speed state of the wheels. Obtainable. The operation of each solenoid valve device may be performed by opening and closing in a pulsed manner.

In addition, 20 is a pump for pumping the oil in the reservoir 106 to the pressure accumulator 6, and 21 and 22 are check valves.

According to the hydro-booster with an anti-skid device having the above configuration, the oil chambers F and H of the normal brake system and the oil chambers A to C of the anti-skid control system are hydraulically independent, and the anti-skid control system is also independent. Since the normal brake system is not affected even if the hydraulic pressure failure occurs, the anti-skid control mechanism, which improves the reliability of the brake system and its operation is rare, is a function of the auxiliary cylinder device that operates during normal braking. Since it is a system in which hydraulic pressure is applied to the power piston, there is an effect that there is almost no risk of problems such as rusting.

Further, in this example, during the anti-skid control, the power piston 103 is returned by the introduction of the hydraulic pressure into the anti-skid oil chamber C, and therefore the pressure oil is returned to the oil chamber F connected to the control oil chamber H. As a result, the hydraulic piston 10 returns to a certain degree in the initial position direction against the depression of the brake pedal.

Due to this operation, even if a hydraulic pressure failure occurs in the system of the other oil chamber G during the anti-skid control, the stroke of the stepping on the brake pedal can be secured to a certain extent. Moreover, there is also an advantage that the brake pedal can be returned within a necessary range by the degree of linkage l between the power piston and the return piston.

〔The invention's effect〕

According to the present invention, since the mechanism that operates during anti-skid control is always operated during normal braking, there is a risk of problems such as sticking of the seal portion as compared with a device that has a piston or the like that moves only during anti-skid control. This is greatly reduced, the reliability of the device is improved, and during the anti-skid control, the operating mechanism in the main cylinder device can be returned to the initial position side by a preset amount.
There is an effect that a large pedal stroke to the brake pedal can be prevented and a necessary pedal stroke can be secured even when one system fails.

[Brief description of drawings]

Drawing is a figure showing an example of composition outline of a hydro booster which is one example of the present invention. 1: Main cylinder device, 3: Control piston 4: Switching piston, 5,7: Return spring 6: Accumulator, 10,11: Hydraulic piston 12,13: Return spring 14: Guide ring, 17,18: Reservoir 19: Reservoir, 20: Pump 100: Secondary cylinder device, 101, 102: Cylinder 103: Power piston, 104: Hydraulic piston 105: Open / close valve, 106: Reservoir 107: Lock rod 108,109: Return spring 110: Set spring, 111: Return piston 112: Large diameter cylinder, 200: Solenoid valve device 201, 202, 203: Path, 204: PSV 205: Hold valve, 206: Pressure reducing valve

Claims (1)

[Claims] 1. A hydro-booster type pedal response device in which the level of introduced hydraulic pressure from a pressure accumulating source is determined depending on the stepping force of a brake pedal, and a master which generates a control hydraulic pressure depending on the hydraulic pressure action of the introduced hydraulic pressure. A main cylinder device having a built-in cylinder type control oil pressure generation mechanism, one end facing a control oil chamber into which the control oil pressure is introduced and the other end facing a brake oil chamber communicating with the brake device,
An anti-skid control oil chamber that has a built-in movable power piston that moves by the hydraulic action of the control oil chamber to generate brake hydraulic pressure in the brake oil chamber, and that exerts an oil pressure in the return movement direction on the movable power piston. And a sub-cylinder device having an anti-skid control oil chamber with an anti-skid signal as an input, which is provided in a path provided to transmit the introduced hydraulic pressure of the pedal response device to the anti-skid control oil chamber of the sub-cylinder device. An anti-skid control solenoid valve device for supplying / discharging pressure oil to and from the hydro booster with an anti-skid device, wherein the sub-cylinder device is connected to the movement of the movable power piston when the brake hydraulic pressure is generated. Engage the return piston that moves in a system when the movable power piston moves from the initial position for a certain length or longer. The hydraulic action force for returning the movable power piston from the anti-skid control oil chamber is transmitted to the movable power piston via the return piston. Hydro booster with anti-skid device.