JPH06191387A - Hydraulic control device for anti-skid device - Google Patents

Abstract

PURPOSE:To greatly reduce kick-back phenomena to brake pedals and noise in a simple structure. CONSTITUTION:In a main frame 29 a pair of pistons 30, 31 are brought into contact with the inside end face of the main frame 29 through springs 32a, 32b, so that the pistons 30, 31 may be moved to the directions of approaching each other by the discharge pressure of hydraulic pumps transmitted to vent holes 29a, 29b. When the liquid pressure of the hydraulic pumps is increased in such a state that the rod 31a of one piston 31 has contact with the other piston 30, the rod is slid crosswise in this state to greatly decrease the pulsation pressure of the hydraulic pumps.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pressure control device for an anti-skid device, which controls a brake hydraulic pressure supplied to a brake cylinder of a wheel brake device in accordance with a skid state of a vehicle wheel, and more particularly to a brake cylinder. The present invention relates to a hydraulic pressure control device in which the discharged brake fluid is pressurized by a hydraulic pump to recirculate in a pressurized fluid supply pipe of a master cylinder.

[0002]

2. Description of the Related Art For example, Japanese Utility Model Laid-Open No. Sho 63-988.
According to Japanese Patent Laid-Open No. 69, in the hydraulic control device of the above-mentioned type, the discharge pressure of the hydraulic pump is received, and free communication in both directions is allowed until the discharge pressure reaches a predetermined value. A throttle valve device for restricting communication in both directions when the value is equal to or more than the value is provided in the pressure liquid supply pipe line, and the hydraulic pump is provided on the side of the pressure liquid supply pipe line between the throttle valve device and the hydraulic pressure control valve. Disclosed is a device to which the discharge port of is connected.

With such a device, the entire device is miniaturized, but the accumulator is not provided, so that the weight is small and the kickback phenomenon to the brake pedal is suppressed so that the driver feels good. However, during repressurization control in the anti-skid control, opening / closing control with the hydraulic pressure control valve is performed, but a hammering sound (impact sound) is generated according to the brake fluid pressure increase acceleration. In addition, vibration of the vehicle body is also generated. Certainly, the phenomenon of kickback to the brake pedal was greatly reduced, but such a phenomenon has not disappeared. Or this gives the driver an unpleasant feeling.

In the device disclosed in Japanese Unexamined Patent Publication No. 1-254459, a cylinder hole 131 is formed in a main body 130 as shown in FIG. 3, and a piston 132 is attached with a seal ring 135 at the center thereof. On both sides thereof, backup plates 136a, 136b are slidable so as to be slidable, and liquid chambers 134a, 134b are defined on both sides thereof, and springs 135a, 135b are stretched in a compressed state on the pistons 132a, 135b. Are positioned in the middle of the cylinder hole 131 in a floating state. The lower wall portion of the main body 130 has an opening 137 that communicates with the liquid chambers 134a and 134b and is connected to the discharge side of the hydraulic pump.
a, 137b, and liquid chambers 134a, 13a.
4b through the throttles 138a, 138b and the check valve 1
It is connected to the master cylinder through openings 140a and 140b through 39a and 139b (the direction toward the master cylinder is the forward direction).

Even with such a device, it is considered that the kickback to the brake pedal connected to the master cylinder is reduced and the noise is also reduced. However, when the brake is reloaded, the hydraulic pump is driven. This discharge pressure is applied to the liquid chambers 134a and 134b and the throttle 138a,
Although it is supplied to the brake cylinder side of the wheel via 138b, a large time delay occurs due to the throttles 138a and 138b, and there is a possibility that quick re-filling cannot be answered.
Further, the liquid chambers 134a and 134b have a considerably large capacity in order to produce the action as described in the specification, which makes the entire apparatus large. Also. It is said that the pulse pressure of the hydraulic pump is reduced by the reciprocating movement of the piston 132, but this is added to the throttles 138a and 138b, and this does not seem to reduce the noise so much as a large resistance.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an anti-cylinder that can reduce the kickback phenomenon to the brake pedal and the noise generated by the hydraulic pump with a simpler structure. An object is to provide a hydraulic control device for a skid device.

[0007]

The above objects are arranged between a master cylinder and a brake cylinder of each wheel brake device connected via two independent brake circuits to evaluate the skid state of the wheel. Control
Each hydraulic pressure control valve that controls the brake hydraulic pressure of the brake cylinder in response to a command from the unit, and when the brake hydraulic pressure is reduced by the control of the hydraulic pressure control valve, the hydraulic pressure control valve from the brake cylinder Reservoirs for storing brake fluid discharged via the reservoirs, and respective hydraulic pumps for pressurizing the brake fluid in the reservoirs and for returning the pressurized fluid to the hydraulic fluid supply pipe line connecting the master cylinder and the hydraulic control valve. In a hydraulic pressure control device for an anti-skid device having a pair of liquid chambers on both sides, which is slidably fitted in the main body between the discharge side of the hydraulic pump and the master cylinder. A pulse pressure damper having a piston for connecting the fluid chamber to each discharge port of the fluid pressure pump, and to the master cylinder, a non-return having a forward direction toward the master cylinder. Connect valve Antiskid device for hydraulic pressure control apparatus characterized by a, is accomplished by.

[0008]

The piston in the pulse pressure buffering device alternately receives the discharge pressure of each hydraulic pump from both sides and reciprocates in the main body, thereby reducing the pulse pressure. Since the fluid chamber is directly connected to the master cylinder via the check valve, not only the pulse pressure of the hydraulic pump, which reduces kickback to the brake pedal and noise, is buffered, but also anti-skid control is performed. When the replenishment by the hydraulic pump is started after the start of the process, the process is performed without passing through the throttle, so that this can be performed quickly.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic control device for an antiskid device according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a master cylinder 1 with a booster
Is driven by stepping on a brake pedal 4, and has a booster section 2 and a hydraulic pressure generating section 3 having a known structure. The hydraulic pressure generating unit 3 has two hydraulic pressure generating chambers built therein, and the pipelines 5a and 5b are connected to these chambers. In this embodiment, the X pipe is applied, but each valve member described later is provided on the pipeline 5a side. The wheel cylinders for the right rear wheel and the left front wheel are connected via the, and the wheel cylinders for the right front wheel and the left rear wheel are connected to the other conduit 5b through similar valve members. Pipeline 5
Since exactly the same piping configuration is connected to a and 5b, only one system, that is, the system of the wheel cylinders of the right rear wheel and the left front wheel will be described, and the corresponding part of the other system will be b instead of a. Shall be attached.

The conduit 5a is connected to the wheel cylinder of the right rear wheel RR via the supply valve 17a and the conduit 18a.
A check valve 19a whose forward direction is from the wheel cylinder side to the master cylinder side is connected to the supply valve 17a in parallel.

A pipe branching from the pipe 5a is connected to the wheel cylinder of the left front wheel FL via the other supply valve 20a and the pipe 22a. A check valve 21a whose forward direction is from the wheel cylinder side to the master cylinder side is also connected to the supply valve 20a in parallel.

Further, exhaust valves 23a and 24a are connected to the wheel cylinders of the right rear wheel RR and the left front wheel FL, respectively, which are connected to a low pressure reservoir 25a. The low-pressure reservoir 25a has a well-known structure, and a piston fixed by a weak spring is slidably fitted in the casing and defines a reservoir chamber in the upper part in the drawing. Further, the hydraulic pump 10 is commonly used with the reservoir 25b of the other system.
The hydraulic pump 10 has a well-known structure, but the eccentric cam mechanism 12 is driven by the electric motor 11, whereby the two pistons are alternately driven left and right in the drawing, and the hydraulic chambers on both sides are driven. The positive pressure and the negative pressure are generated, and the reservoir 2 is connected via a check valve 13a connected to these hydraulic chambers.
Brake fluid is sucked from 5a. Also, the check valve 13a
It is connected to the pulse pressure damping device 7 according to the present invention via. This is further connected with a check valve 14a whose forward direction is toward the master cylinder 1 side.

The above-mentioned supply valves 17a and 20a and the discharge valve 2
Reference numerals 3a and 24a denote electromagnetic switching valves each having a solenoid portion, which is configured to take a communication state or a blocking position shown in the drawing when it is not excited, and to take a blocking position or a communication position when it is excited.

Next, the details of the pulse pressure damper 7 will be described with reference to FIG. A cylinder hole is formed in the main body 29 and is divided into two chambers by a partition wall portion 29e. The seal rings 33a and 33b are formed in these chambers, respectively.
A pair of piston parts 30 and 31 fitted with are fitted slidably so that the partition part 2
Air chambers 39a and 39b are defined on both sides of 9e, and liquid chambers 35a and 35b are defined between the piston portions 30 and 31 and the end wall portion of the main body 29. Further, through holes 100a and 100b are formed in the main body 29, and the air chambers 39a and 39b are always communicated with the atmosphere through the through holes 100a and 100b. Through holes 29a and 29b are formed in the lower wall portion of the main body 29, which are on the discharge side of the hydraulic pump, that is, the check valve 13.
a, 13b and through holes 29c, 2 in the upper wall.
Although 9d is formed, these are connected to the check valves 14a and 14b in FIG. Also, the spring 32a,
The piston portions 30 and 31 are normally in contact with the inner end wall of the main body 29 by 32b as shown in FIG.
The capacity of 35b is minimized.

A rod portion 31a is integrally formed at the center of one piston portion 31 of the pair of piston portions 30 and 31, and is slidable in the opening formed in the partition wall portion 29e. It is fitted and faces the other piston 30 at a predetermined interval. Also, the piston parts 30, 31
The distance between the inner end surface and the partition wall portion 29e is set to be equal.

The hydraulic control device for an anti-skid device according to the embodiment of the present invention is constructed as described above, and its operation will be described below.

When the brake pedal 4 is depressed, a boosting force assisting action of the booster portion 2 is added to generate a hydraulic pressure in the hydraulic pressure generating portion 3. This is transmitted to the front and rear wheels that are X-piped through the pipes 5a and 5b, but only one system will be described. That is, the hydraulic pressure from the conduit 5a is applied to the supply valve 17a and the conduit 18
It is transmitted to the wheel cylinder of the rear wheel RR through a. Further, it is transmitted to the wheel cylinder of the left front wheel FL through the supply valve 20a and the pipe 22a via a pipe branched from the pipe 5a. Therefore, all wheels are braked.

When a control unit (not shown) judges that the brake should be released (the wheels RR and FL of one system are in the same skid state for the sake of clarity), the solenoid portions of the supply valves 17a and 20a. Is energized, the pipe line 18a side and the pipe line 5a side are cut off, and the solenoid portions of the discharge valves 23a, 24a are energized to establish a communication state, and the right rear wheel RR and the left front wheel FL are
The brake fluid is discharged to the reservoir 25a from the wheel cylinder through the discharge valves 23a and 24a. At the same time, the hydraulic pump 10 is driven, the brake fluid is immediately sucked from the reservoir 25a, passes through the check valve 13a, and the pulse pressure damping device 7
Is supplied to. Here, the pulse pressure of the hydraulic pump 10 is greatly reduced and transmitted to the hydraulic fluid supply line 5a through the check valve 14a.

When the hydraulic pump 10 is started as described above, the discharge pressure has a phase difference of 180 degrees from the check valves 13a, 13b side, and the liquid chambers 35a, 35b in the pulse pressure damper 7 are provided. This hydraulic pressure is transmitted to the springs 32a and 32b and the seal rings 33a and 33b.
When a predetermined pressure determined by the sliding resistance of b and the pressure receiving area of the piston portions 30 and 31 facing the liquid chamber side is reached, both the piston portions 30 and 31 move inward against the spring force of the springs 32a and 32b. 2B, and when the discharge pressure of the hydraulic pump increases, the rod portion 31a of the first piston 31 comes into contact with the inner end surface of the other piston 30 and becomes integrated. The piston P alternately applies a discharge pressure to the liquid chambers 35a and 35b with a phase difference of 180 degrees and slides to the left and right from the state of B in FIG. 2, and the volume of the liquid chambers 35a and 35b expands and decreases, and a buffering action is provided. Receive. Therefore, the pulse pressure is greatly reduced and transmitted to the master cylinder 1 side. The kickback phenomenon to the brake pedal 4 becomes good, and the noise is greatly reduced. Further, according to the present embodiment, the pulse pressure damper 7 and the master cylinder 1 are simply connected via the check valves 14a and 14b, so that the hydraulic pump is used for reloading during the anti-skid control. The hydraulic pressure of 10 can be quickly transmitted to each wheel, and the anti-skid control can be improved. Further, unlike the conventional example, since the throttles are not connected to the liquid chambers 35a and 35b, respectively, the structure is much simpler. Further, as shown by A in FIG.
a, 35b can start expanding from a very small capacity compared with the conventional one, and can also start moving only by overcoming the spring force of the springs 32a, 32b stretched over the air chambers 39a, 39b, that is, the hydraulic pump. Since its discharge pressure can be made much smaller and its capacity can be made larger, its buffering effect is very large.

Further, according to this embodiment, since the equal predetermined distance is provided between the partition wall portion 29e and the inner end surfaces of the piston portions 30 and 31, the other system fails,
Even if the discharge pressure from the hydraulic pump corresponding to this becomes 0, the piston part of the normal system abuts against the partition wall part 29e, so that the piston part is prevented from moving further and the damping action is effectively made as a damper chamber. Can be done.

The above-mentioned hammering noise and vibration are caused by the connection between the brake pedal / booster combination and the vehicle, the connection between the master cylinder and hydraulic control valve and the vehicle, the hydraulic control valve and the wheel. According to the present invention, the pulse pressure damping device 7 is provided between the discharge port of the hydraulic pump and the master cylinder. Therefore, the hammering noise and vibration transmitted to the driver and the passengers through the above-mentioned connecting portion are greatly reduced or become almost zero.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention.

For example, although the master cylinder 1 with a booster has been described in the above embodiments, the present invention can be applied to a vehicle equipped with a normal tandem master cylinder without a booster.

In the above embodiment, the fluid pressure control valve is composed of two changeover valves of the supply valves 17a and 20a and the discharge valves 23a and 24a, but instead of this, one changeover valve, for example, 3 port 3 is used. You may make it use one position electromagnetic switching valve.

Further, in the above embodiment, the hydraulic control valve is provided for each wheel. That is, although the four-channel type hydraulic control valve has been described, the present invention can also be applied to one hydraulic control valve for each system, that is, the two-channel type.

Further, in the above embodiment, the piston is composed of the pair of piston portions 30 and 31 in the pulse pressure damping device 7, but this may be composed of a single piston body.

[0028]

As described above, according to the hydraulic control device for an anti-skid device of the present invention, the kickback phenomenon to the brake pedal coupled to the master cylinder and the noise generated from inside the device are prevented with a simple structure. It can be made very small or almost eliminated.

[Brief description of drawings]

FIG. 1 is a piping system diagram of a hydraulic control device for an anti-skid device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the pulse pressure damper shown in FIG.
Indicates a normal state, and B indicates its operating state.

FIG. 3 is a sectional view of a pulse pressure damping device in a conventional hydraulic control device for an anti-skid device.

[Explanation of symbols]

 7 Pulse Pressure Damper 30 Piston Part 31 Piston Part 32a Spring 32b Spring 35a Liquid Chamber 35b Liquid Chamber

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[Procedure amendment]

[Submission date] February 23, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

Further, exhaust valves 23a and 24a are connected to the wheel cylinders of the right rear wheel RR and the left front wheel FL, respectively, and these are connected to a low pressure reservoir 25a.
The low-pressure reservoir 25a has a well-known structure, and a piston fixed by a weak spring is slidably fitted in the casing and defines a reservoir chamber in the upper part in the drawing.
Further, the hydraulic pump 1 is commonly used with the reservoir 25b of the other system.
0 is connected, and this hydraulic pump 10 has a well-known structure, but an eccentric cam mechanism 12 is driven by an electric motor 11, whereby two pistons are alternately driven left and right in the figure, and hydraulic chambers on both sides are driven. Positive pressure and negative pressure are generated in the reservoir 2 via the check valve 13a connected to these hydraulic chambers.
Brake fluid is sucked from 5a. Also, the check valve 1 5 a
It is connected to the pulse pressure damping device 7 according to the present invention via. This is further connected with a check valve 14a whose forward direction is toward the master cylinder 1 side.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

When the brake pedal 4 is depressed, the boosting force assisting action of the booster portion 2 is added, and hydraulic pressure is generated in the hydraulic pressure generating portion 3. This is transmitted to the front and rear wheels that are X-piped through the pipes 5a and 5b, but only one system will be described.
That is, the hydraulic pressure from the conduit 5a is supplied to the supply valve 17a and the conduit 1.
It is transmitted to the wheel cylinder of the right rear wheel RR through 8a. Further, the supply valve 20a is provided through a pipe branching from the pipe 5a.
And is transmitted to the wheel cylinder of the left front wheel FL through the pipe line 22a. Therefore, all wheels are braked.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction content]

When a control unit (not shown) judges that the brake should be released (the wheels RR and FL of one system are in the same skid state for the sake of clarity), the solenoid portions of the supply valves 17a and 20a. Is energized, the line 18a side and the line 5a side are cut off, and the solenoid portions of the discharge valves 23a, 24a are excited to establish a communication state, and the discharge valves are discharged from the wheel cylinders of the right rear wheel RR and the left front wheel FL. The brake fluid is discharged to the reservoir 25a through 23a and 24a. At the same time, the hydraulic pump 10 is driven, and the brake fluid is immediately sucked from the reservoir 25a and supplied to the pulse pressure damping device 7 through the check valve 13a. Here, the pulse pressure of the hydraulic pump 10 is greatly reduced and transmitted to the hydraulic fluid supply line 5a through the check valve 14a.

Claims (2)

[Claims] 1. A command from a control unit, which is arranged between a master cylinder and a brake cylinder of each wheel brake device connected via two independent brake circuits, receives a command from a control unit for evaluating the skid state of the wheel. hand,
Each hydraulic pressure control valve for controlling the brake hydraulic pressure of the brake cylinder, and the brake fluid discharged from the brake cylinder via the hydraulic pressure control valve when the brake hydraulic pressure is reduced by the control of the hydraulic pressure control valve. For an anti-skid device, which is provided with each of the reservoirs that store the liquid and a hydraulic pump that pressurizes the brake fluid in the reservoir and recirculates the pressurized hydraulic fluid to a hydraulic fluid supply pipe that connects the master cylinder and the hydraulic control valve. In a fluid pressure control device, a pulse pressure buffer device having pistons that slidably fit in a main body between a discharge port side of the fluid pressure pump and the master cylinder to define a pair of fluid chambers on both sides. Is provided, the liquid chamber is connected to each discharge port of the hydraulic pump, and the master cylinder is connected to a check valve whose forward direction is toward the master cylinder. Antis Head device for a fluid pressure control apparatus. 2. The piston is composed of a pair of piston parts, and the piston part is formed by a biasing force of a spring arranged in a compressed state between a partition wall formed in an intermediate part of the main body and the piston parts. It is in contact with each bulkhead of the main body,
The anti-skid according to claim 1, wherein one of the pair of piston portions forms a rod portion extending to the other side so as to be slidable in an opening formed in the partition wall, and an air chamber is provided between the pair of piston portions. Hydraulic control device for equipment.