JPH0580384B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an anti-skid control device, and more particularly to an anti-skid control device integrated with a hydrobooster.

[Background of the invention]

Conventionally, various devices have been proposed for use in vehicle braking systems, such as hydro boosters as boosting mechanisms and anti-skid control devices to prevent wheel locking during braking. Generally configured as individual devices.

However, since these are incorporated into a single system called the vehicle brake, if they are skillfully combined to form an integrated unit, it will be easier to assemble into the vehicle, and it will also improve the structure. If functional improvement is achieved, its usefulness will be extremely large.

By the way, when configuring such a hydrobooster-integrated anti-skid control device, for example, when the vehicle brake hydraulic system is of a two-system type to improve safety, one system is connected to the hydrobooster operation. If the other system is a hydraulic pressure generation type using normal piston pressure, and the latter normal system uses hydraulic pressure from the pressure accumulation source of the hydro booster system for anti-skid control, then either system It is conceivable that a failure may have an adverse effect on either system.

[Purpose of the invention]

The present invention has been made from this viewpoint,
The purpose is to provide a device that incorporates and integrates a hydrobooster for a vehicle brake system and an anti-skid device.

Another object of the present invention is to realize miniaturization of the entire device through such integration.

Still another object of the present invention is to provide a device that can ensure a certain degree of vehicle braking force even when one system fails.

[Summary of the invention]

The features of the anti-skid control device integrated with a hydro booster according to the present invention, which has been made to achieve such an object, are as follows: Hydraulic pressure transmission control mechanism (ii) that transmits the hydraulic pressure to the proportional hydraulic pressure generating device of the first brake hydraulic system;
Brake hydraulic system hydraulic pressure generating mechanism (iii) A master cylinder type brake pedal response device having each of the mechanisms (i), (ii), and (iii) of a fail-safe hydraulic pressure generating mechanism that generates a fail-safe hydraulic pressure, and the first brake hydraulic pressure. A proportional hydraulic pressure generating device that generates a first brake hydraulic pressure by a power piston that moves in response to transmission hydraulic pressure for the system, and the pressure accumulation device for anti-skid control for each of the first and second brake hydraulic systems. a hydraulic supply/discharge solenoid valve device that supplies hydraulic pressure from a source and discharges hydraulic pressure to a release tank; is connected to the brake device of the first brake hydraulic system and transmits fail-safe hydraulic pressure to the brake device side when hydraulic input from both of the latter is released; and a switching valve device whose input is the hydraulic pressure of the second brake hydraulic system. a gate valve device connected to the hydraulic pressure generating mechanism and having an output connected to a brake device of a second brake hydraulic system, normally communicating the brake device with the hydraulic pressure generating mechanism, and cutting off the communication during anti-skid control. It's somewhere.

[Embodiments of the invention]

The present invention will be described in detail below based on an embodiment shown in the drawings.

In the following description, the hydraulic pressure generating mechanism of the second brake hydraulic system will be referred to as a master cylinder mechanism for convenience.

In the figure, 1 is a cylinder body that houses a third cylinder that houses a master cylinder mechanism, a stepped first cylinder that houses a transmission hydraulic pressure control valve mechanism, and a fail-safe oil generation mechanism located between these cylinders. A second cylinder is provided coaxially with the second cylinder.

First, the configuration inside the first cylinder will be explained. This means that the control piston 3, in which a suitable flow path is formed, is slidably fitted into the first cylinder.
Rear end (right end in the figure) by return spring 5
It is pressed and biased towards the opening side. A flow path switching piston 4 is slidably fitted into the internal cylinder 3a of the control piston 3, and a ball joint receiver 2 is provided at the rear end thereof.
A push rod 2 is engaged through a.
The push rod 2 is connected to a brake pedal (not shown) at the right end in the figure, and when the brake pedal is depressed, the switching piston 4 is first pressed and moved.

The transmission hydraulic pressure control valve mechanism constituted by the relationship between the control piston 3 and the switching piston 4 is in the state shown in the figure when not braking, and has an oil chamber G and a hydraulic release oil chamber H.
are communicated through a passage 4a, and when the switching piston 4 is embedded relative to the control piston 3 due to the pressing force of the push rod 2, the oil chamber G
~H is closed, and the pressure source side oil chamber G' and the oil chamber G are communicated with each other. Note that the oil chamber G' is connected to the pressure accumulator 6.

In the above, when hydraulic pressure is transmitted to the oil chamber G through the communication between the oil chambers G' to G, hydraulic pressure opposing the pushing force of the push rod 2 acts on the switching piston 4, and this causes the pedal to be depressed. Acts as a reaction force to a force. Therefore, in oil chamber G,
The oil pressure in the oil chamber is proportional to the force applied to the brake pedal.
G', and in this state, communication between oil chambers G', G, and H is cut off.

Note that the above-mentioned configuration inside the first cylinder itself may be substantially the same as that known as a so-called hydro booster mechanism. Note that 7 is a return spring for the switching piston 4.

Next, talking about the configuration inside the second cylinder, this is made by press-fitting a small-diameter piston 3b into the front end (left end in the figure) of the control piston 3 and integrating the integrated control piston 3 with the stepped second cylinder. This constitutes a fail-safe oil pressure generating mechanism in which a fail-safe oil chamber A is formed between the two.

A pressure oil passage H' is formed in the small diameter piston 3b, and communicates the oil pressure release oil chamber H with the reservoir 8.

The third cylinder accommodates a general master cylinder type hydraulic pressure generating mechanism, and a return spring is installed so that the rear end of the hydraulic pressure generating piston 9 faces the small diameter piston 3b of the control piston 3 during non-braking. 10.
If the master cylinder oil chamber in which oil pressure is generated by this oil pressure generating piston 9 is E, this oil chamber E
The hydraulic pressure generated in is the brake hydraulic pressure for the second brake hydraulic system. Note that 12 is a pump that pumps pressure oil from the reservoir 8 to the pressure accumulator 6.

In the master cylinder type brake pedal response device configured as described above, each movable member is in the position shown in the figure when the brake is not applied, and therefore the oil chamber
G′~G are shut off, oil chamber G~H~reservoir is connected,
No oil pressure is generated in the fail-safe oil chamber A and the master cylinder oil chamber E.

During braking, the oil chambers G to H are shut off, and the oil chambers G' to G are communicated with each other, so that hydraulic pressure proportional to the force applied to the brake pedal is transmitted to the oil chamber G. Further, a predetermined hydraulic pressure is generated in the master cylinder oil chamber E in proportion to the depression force on the brake pedal.

The fail-safe oil chamber A is configured to generate a predetermined hydraulic pressure in proportion to the depression force of the brake pedal, but normally no hydraulic pressure is generated due to the function of a switching valve device 26, which will be described later.

As mentioned above, the hydraulic pressure generated in the master cylinder oil chamber E is the brake hydraulic pressure of the second brake hydraulic system, but the brake hydraulic pressure of the first brake hydraulic system is the hydraulic pressure of the oil chamber G that is proportional to the hydraulic pressure of the oil chamber G. By transmitting it to the hydraulic pressure generating device 13, it is generated by this proportional hydraulic pressure generating device.

Proportional hydraulic pressure generator with built-in power piston 13
In this example, a power piston 14 for generating brake oil pressure during normal braking;
A hydraulic piston 17 has a built-in opening/closing valve 15 that cooperates with the power piston 14 to generate brake hydraulic pressure during normal braking, and transmits the hydraulic pressure generated in the oil chamber A to the brake device side during a failure.
It consists of a combination of

When the oil pressure from the oil chamber G is transmitted to the oil chamber C, the power piston 14 moves under the hydraulic action of the oil chamber C, and applies a moving force to the hydraulic piston 17. On the other hand, the hydraulic piston 17 has a passage 17a passing through in the axial direction,
Normally, the ball 18 is separated from the valve seat 17b by the engagement with the locking rod 16, opening the flow passage 17a, and the power piston 14 opens the extending portion 17c.
is pressed to cause movement of the hydraulic piston 17, the engagement by the locking rod 16 is released, and the ball 18 is seated on the valve seat 17b, thereby closing the check valve type on-off valve 15 that closes the flow path 17a. , is built in this flow path 17a.

The oil chamber A' facing the power piston side end of the hydraulic piston 17 communicates with the fail-safe oil chamber A, and the oil chamber B facing the opposite end of the hydraulic piston 17 communicates with the foil cylinder W/of the brake device.
It is connected to C.

As described above, when the oil pressure is transmitted to the oil chamber C, the power piston 14 moves and presses the hydraulic piston 17, which closes the on-off valve 15, and from then on, the oil pressure in the oil chamber B is proportional to the oil pressure in the oil chamber C. The brake hydraulic pressure, that is, the brake hydraulic pressure of the first brake hydraulic system is generated.

Note that 19 and 20 are return springs, and 21 is a hold spring for the locking rod.

Next, the hydraulic pressure supply/discharge solenoid valve devices for anti-skid control provided for each of the first and second brake hydraulic systems will be described.

The hydraulic pressure supply/discharge solenoid valve device for the first brake hydraulic system in this example includes a normally open solenoid valve 22 installed in a path connecting the oil chambers G to C, and a reservoir 8 for transferring the pressure oil in the oil chamber C. It consists of a normally closed electromagnetic valve 23 interposed in a path for internal release.

Further, the hydraulic pressure supply/discharge solenoid valve device of the second brake hydraulic system uses normally open type solenoid valves 24, 24 connected between the oil chamber E and the two sets of brake devices, respectively, and the pressure oil in the brake devices to a reservoir 8. It consists of a combination of normally closed electromagnetic valves 25, 25 connected to a path for releasing the air.

These normally open and normally closed solenoid valves are controlled to open and close by an anti-skid control circuit (not shown) to reduce and increase the hydraulic pressure in the brake device, but the control method is based on a known method. Just use it.

The switching valve device 26 for transmitting the fail-safe hydraulic pressure of the first brake hydraulic system to the proportional hydraulic pressure generating device 13 is explained as follows: The switching valve device 26 is composed of a stepped piston 29 that is slidably fitted in stepped cylinders 27 and 28, and a stepped piston 29 that is slidably fitted in stepped cylinders 27 and 28. The piston 29 with oil chamber E′,
It consists of a set spring 30 that presses in the G'' direction, and a one-way valve 31 that is normally open and releases the oil pressure in the fail-safe oil chamber A to the reservoir via the oil chamber D. The oil chamber A'', which is separated from the oil chamber D through 31, is the oil chamber A''.
~ A′ forms an intermediate oil chamber that is constantly in communication. The stepped piston 29 of this example is configured to operate the one-way valve 3 when there is no oil pressure in either the oil chamber E' or G''.
1 is closed, and the hydraulic pressure in the fail-safe oil chamber A is transmitted to the oil chamber A' of the proportional hydraulic pressure generator. The oil chamber E' is communicated with the master cylinder oil chamber E of the second brake hydraulic system, and the oil chamber G'' is connected to the oil chamber E.
It is connected to the pressure accumulation source via G'.

According to such a switching valve device,
Normally, the fail-safe hydraulic pressure is released, and the fail-safe hydraulic pressure is transmitted to the brake device of the first brake hydraulic system when the second brake hydraulic system fails and the pressure accumulation source fails.

Next, the gate valve device 32 will be explained. The gate valve device 32 of this example includes a normally open type gate valve 33 interposed between the master cylinder oil chamber E and the electromagnetic valves 24, 24, and this gate valve 33. A normally closed hydraulic pressure introduction solenoid valve 35 that applies control hydraulic pressure for flow path closing to the piston 34 from the oil chamber G.
and a one-way valve 36 that transmits the introduced hydraulic pressure only to the brake device side. Normally, the piston 34 is biased to the initial position by the spring force of the set spring 37 to open the flow path, and a command to start anti-skid is issued. When the oil pressure introduction valve 35 is opened, the piston 34 closes the flow path. Therefore, in the second brake hydraulic system, during normal braking, the hydraulic pressure in the master cylinder oil chamber E is transmitted to the brake device to perform a braking operation, and at the start of anti-skid control, the gate valve is opened by opening the hydraulic pressure introduction valve 35. 33 is closed, and the solenoid valve 2 is closed downstream of the gate valve 33 without causing any oil pressure fluctuation in the master cylinder oil chamber E.
It becomes possible to perform pressure reduction and pressure increase control of the brake hydraulic pressure by opening and closing the brake valves 4 and 25.

To describe the operation of the anti-skid control device integrated with the hydro booster of this example having the above configuration, during normal braking, the first brake hydraulic system operates in the proportional hydraulic pressure generating device 13 depending on the hydraulic pressure in the oil chamber G mentioned above. Brake hydraulic pressure of the first brake hydraulic system is generated by the power piston 14, and brake hydraulic pressure of the second brake hydraulic system is generated in the master cylinder oil chamber E of the second brake hydraulic system. These hydraulic pressures are then transmitted to the corresponding brake devices.

During anti-skid control, the brake hydraulic pressure in the oil chamber C in the first brake hydraulic system is controlled by the solenoid valve 2.
Anti-skid control of the brake hydraulic pressure is performed by reducing, holding, and increasing pressure by switching the opening and closing of the brake hydraulic pressure system 2 and 23. On the other hand, in the second brake hydraulic system,
For each brake device, first, communication between the master cylinder oil chamber E and the brake device is cut off by closing the gate valve 33 of the gate valve device 32, and then, using the hydraulic pressure introduced from the oil chamber G, the solenoid valve 24, Anti-skid control of the brake hydraulic pressure is performed by switching the opening and closing of the brake valve 25.

Next, a case will be described in which a failure occurs in the second brake hydraulic system and the hydro booster system.

When the pressure accumulation source of the first brake hydraulic system fails, in this case, there is no hydraulic pressure transmitted to the oil chamber C, so no hydraulic pressure is generated within the proportional control hydraulic system 13;
When the one-way valve 31 closes, the switching valve device 26 transfers the fail-safe hydraulic pressure generated in the oil chamber A of the fail-safe hydraulic pressure generating mechanism to the oil chamber.
A', and therefore fail-safe hydraulic pressure is ensured in the first brake hydraulic system.

When the brake equipment side of the first brake hydraulic system fails In this case, the second brake hydraulic system generates and transmits brake hydraulic pressure in the same way as in normal times, and the anti-skid control also works as in normal times because the pressure accumulation source is normal. The same is done.

When the second brake hydraulic system fails, in this case, the normal brake generates the same brake hydraulic pressure as normal in the first brake hydraulic system,
A communication is made. During anti-skid control, a failure in the second brake hydraulic system is detected by an appropriate detection means (a combination of a pressure switch and a brake pedal depression detection switch, etc.), and the hydraulic pressure introduction solenoid valve of the gate valve device 32 is activated. 35 from closed to open, the same anti-skid control as usual is ensured in the first brake hydraulic system, and even if the deactivation of the hydraulic pressure introduction solenoid valve 35 is delayed, the oil chamber G, that is, the pressure accumulation source 6 Even if the hydraulic pressure leaks, the hydraulic pressure transmission from the fail-safe oil chamber A to the oil chamber A' is ensured, and a complete no-brake condition is prevented from occurring.

It goes without saying that the present invention is not limited to the one embodiment described above, and it goes without saying that various modifications can be made to the constituent devices of each part. For example, the gate valve of the gate valve device may be a solenoid valve. Alternatively, the switching valve may transmit the oil pressure in the fail-safe oil chamber A to the oil chamber A' only when either the master cylinder oil chamber E or the pressure accumulation source disappears.

〔Effect of the invention〕

As described above, the anti-skid control device integrated with a hydro booster according to the present invention can simplify the structure by integrating two devices, and also has a fail-safe concept in the mutual relationship between the two brake hydraulic systems. Its usefulness is extremely significant, as improvements have been achieved.

[Brief explanation of drawings]

The drawing is a schematic diagram of the configuration of an apparatus showing an embodiment of the present invention. 1: Cylinder body, 2: Push rod,
3: Control piston, 4: Switching piston, 6: Pressure accumulator, 8: Reservoir, 9: Hydraulic pressure generating piston, 1
3: Proportional oil pressure generator, 14: Power piston,
15: Open/close valve, 16...Latching rod, 17: Hydraulic piston, 22, 24: Normally open type solenoid valve, 23, 25: Normally closed type solenoid valve, 26: Switching valve device, 2
9: Stepped piston, 31: One-way valve, 32: Gate valve device, 33: Gate valve, 35: Hydraulic pressure introduction solenoid valve.

Claims (1)

[Scope of Claims] 1. A pressure accumulation source, and (ii) a transmission hydraulic pressure control valve mechanism that transmits (i) the hydraulic pressure of the pressure accumulation source to the proportional hydraulic pressure generating device of the first brake hydraulic system in proportion to the depression force of the brake pedal. 2. The second brake system generates hydraulic pressure for the brake hydraulic system.
Brake hydraulic system hydraulic pressure generating mechanism (iii) A master cylinder-type brake pedal response device each having a fail-safe hydraulic pressure generating mechanism that generates a fail-safe hydraulic pressure, and a power piston that moves by receiving the transmission hydraulic pressure for the first brake hydraulic system. , a proportional hydraulic pressure generating device that generates a first brake hydraulic pressure, and a hydraulic pressure generator for supplying hydraulic pressure from the pressure accumulation source and discharging hydraulic pressure to a release tank for anti-skid control to each of the first and second brake hydraulic systems. a hydraulic pressure supply/discharge solenoid valve device having an input connected to the fail-safe hydraulic pressure generating mechanism, the second brake hydraulic system hydraulic pressure generating mechanism and the pressure accumulation source, and an output connected to the brake device of the first brake hydraulic system; a switching valve device that transmits fail-safe hydraulic pressure to the brake device side when hydraulic pressure input from both of the latter is released; A hydro booster-type anti-skid control device, comprising: a gate valve device connected to a brake device of a system, which normally communicates the brake device with the hydraulic pressure generation mechanism and shuts off the communication during anti-skid control. .