JPH02136359A - Hydraulic controller for skid preventing device - Google Patents

Abstract

PURPOSE:To prevent the liquid pressure fluctuation or the like by adding a valve mechanism performing the specific action to the second hydraulic control valve lowering the brake liquid pressure of a high-pressure system brake according to the liquid pressure difference of two systems in hydraulic control valves arranged on two systems with the X pipeline respectively. CONSTITUTION:One liquid pressure generating chamber of a master cylinder 10 is connected to the right front wheel brake 151 via a selector valve (first hydraulic control valve) 12a and connected to the left rear wheel brake 21b via a conduit 13, a hydraulic control valve (second hydraulic control valve) 16 and a conduit 19. The other liquid pressure generating chamber of the master cylinder 10 is likewise connected to the left front wheel brake 15b and the right rear wheel brake 21a. In this case, a valve ball 49, a stem 50 and a valve ball 54 are arranged in sequence at end sections of a pair of stepped plungers 42a and 42b inserted into the cylinder 40 of the hydraulic control valve 16 to form a valve mechanism 55, and it is operated in the direction to lower the brake liquid pressure of a high-pressure system brake according to the liquid pressure difference between two systems with the X pipeline.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field-1 This invention relates to a hydraulic pressure control device for a skid prevention device that independently controls two systems of X piping.

"Conventional technology" Skit prevention devices conventionally used in vehicles are:
This pipe is installed in the middle of the conduit that transmits the pressure of the brake fluid in the master cylinder operated by the brake pedal to the wheel cylinder of each wheel.When the wheels approach a locked state due to sudden braking, By alternately depressurizing and pressurizing the brake fluid, the wheels are prevented from becoming locked and the braking distance is shortened.

Among these skid prevention devices, the two-channel type skid prevention device that independently controls two systems of A hydraulic pressure control device for eliminating the difference in hydraulic pressure between the rear pipes is provided as shown in Japanese Patent Laid-Open No. 61-41657.

As shown in Fig. 3, this hydraulic pressure control device (variable volume type) is controlled by the control pressure from the mask ring introduced from the first person's capo 1□a or from the second person's capo 1-1l). If the pressure is higher than the introduced control pressure, the input chamber 3a on the high pressure side
The inner valve ball 4 cuts off communication to the output chamber 5a, and
The piston 6 presses and slides toward the input chamber 31 on the low-pressure side, and the movement of the piston 6 increases the volume of the output chamber 5b on the high-pressure side, thereby increasing the volume of the output chamber 5b on the first output capo) and after 7a (rear circuit).
The hydraulic pressure of each rear pipe is lowered so that the hydraulic pressure of each rear pipe becomes the same pressure. It has also been proposed to compare and introduce the mask-and-ring hydraulic pressures of the two systems in order to cancel the above function in the event of failure of the l system. The volume was changed by decreasing the high pressure system and increasing the low pressure system.

"Problem to be Solved by the Invention" However, since the hydraulic pressure control device with the conventional configuration described above is of a variable volume type, the operating stroke of the piston 6 is large.
For this reason, it may take time for the piston 6 to return, resulting in a delay in brake response, which may reduce braking performance, or may reduce the volume of the rear pipe on the low pressure side, leading to unexpected fluid pressure changes. Ta. Furthermore, there were also problems such as mask-on-linta, overstroke during undeskid operation of the piston inside, and negative effects on the petal fee link.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic pressure control device for a skid prevention device that can solve the problems of the variable displacement type as described above and improve braking performance.

"Means for Solving the Problems" This invention provides a first system that is arranged between two systems, a mask ring and an a hydraulic control valve;
When the brake fluid pressure is lowered by controlling the first fluid pressure control valve, a reservoir is used to store the brake fluid discharged from the wheel cylinder through the fluid pressure control valve, and the brake fluid in this reservoir is added to the reservoir. a hydraulic pump for pressurizing the fluid and returning the fluid to a pressure fluid supply pipe connecting the mask ring and the first hydraulic pressure control valve; and - disposed between the wheel cylinders of the pair of front wheels or the pair of rear wheels. and a second hydraulic pressure control valve, the second hydraulic pressure control valve is a skit configured to reduce the brake hydraulic pressure of the wheel cylinder of the high pressure side system according to the hydraulic pressure difference between the two systems of the X piping. A hydraulic pressure control device for a prevention device, wherein the second hydraulic pressure control valve is provided with a pipe line on the wheel cylinder side where the high pressure system of the two systems is cut off, and at which time the pressure of the high pressure system is to be reduced. A valve mechanism is provided to connect the tank and the reservoir side pipe line.

Effect-1 For example, if a difference occurs in the brake fluid pressure between a pair of front wheels in the two systems of the The brake fluid in the wheel cylinder on the rear wheel side of the high-pressure system escapes into the conduit on the reservoir side and is reduced in pressure. The brake fluid pressure at the wheels is also controlled.

Embodiment FIGS. 1 and 2 show an embodiment of the present invention, and FIG. 1 is a piping system diagram of a hydraulic pressure control device for a skid prevention device.

In FIG. 1, one of the hydraulic pressure generation chambers of the mask ring 10 is connected to the right front wheel via a pipe (pressure liquid supply pipe) 11, a switching valve (first hydraulic pressure control valve) 12a, and a pipe 13. 14a is connected to the wheel cylinder 15a. The pipe line 13 is connected to a first human-powered boat 17 of a hydraulic pressure control valve (second hydraulic control valve) 16, which will be described later. The first output boat 18, which communicates with the normally first input port 17 of the hydraulic pressure control valve 16, is connected to the pipe line 1.
9 to the wheel cylinder 211 of the left rear wheel 20b)
connected to. In addition, PCV is rear wheel 20a, 201)
This control valve controls the hydraulic pressure of the boiling rings 21a and 21b to be lower than the hydraulic pressure of the mask ring 10.

The other hydraulic pressure generation chamber of the Musk Schilling IO includes a pipe line (pressure liquid supply pipe line) 22, a switching valve (first liquid pressure control valve) +2b,
The wheel cylinder 1 of the left side mower 14b is connected via the conduit 23.
Connect to 5F). The pipe line 23 is connected to the second hydraulic pressure control valve 16.
Connected to person capo 1-24. A second output capo I/25 of the hydraulic pressure control valve 16 normally communicates with the second capo 1-24.
is connected to the wheel cylinder 21a of the right rear wheel 20a via a conduit 26.

The switching valves (first hydraulic control valves) 12a and +2b are controlled by control signals A, B, and C from a control unit (not shown) that evaluates the braking situation of the wheels using slip rate, deceleration, etc. You can now select the location of the image. Position A is the brake engagement position where the mask cylinder side and the wheel cylinder side are in communication, and position B is the brake engagement position where the mask cylinder side and the wheel cylinder side are in communication.
and the brake holding position where the communication between the wheel cylinder side and the reservoir side is cut off, and position C is the brake holding position where the communication between the mask ring side and the wheel cylinder side is cut off, but the communication between the wheel cylinder side and the wheel cylinder side is cut off. This is the brake gear loosening position where there is communication with the reservoir side.

The outlet of such switching valves 12a and 12b is the pipe line 27a.
, 27b to the piston 29a29b and the spring 30a,
30b. Reservoirs 28a, 28b are check valves 35a, 35b
The hydraulic pump 3I is connected to the hydraulic pump 3I, and its discharge port is connected to the pipe line 11.22 via check valves 34a and 34b.

The main body of the hydraulic control valve 16 has a sill 4 extending in the axial direction.
0 is formed, and a pair of opposing stepped plantains 4.2a and 42b equipped with a knoll ring 41 are slidably fitted approximately in the center of the cylinder 40. Each of the plungers 42a and 42b is composed of a large-diameter portion 43 housed in a sliding chamber 40a at the center of the sill 40, and a shaft portion 44 that is formed integrally with the large-diameter portion 43 and extends left and right, respectively. ing. The shaft portion 44 is the cylinder 4
0 to the output chambers 4.5a, 45b, and is lockable on the inner surface of the output chambers 4.5a, 451).
．． 46 and is biased by a spring 4747 in the output chambers 45a, 45b. Therefore, the pair of planters 42a, 42b are connected to the springs 4.7.47.
The large diameter part 4 depending on the force
The step portions 43a and 43a of the rollers 3 and 43 are in contact with each other and are in a neutral state.

The shaft portion 44 has a small diameter portion 44 which is located inside from the rear end portion 44a.
A liquid passage 48 extending up to 1J and opening on the side thereof is bored, and the pipe lines 27a and 27b connected to the aforementioned reservoirs 30a and 30b are connected to the inner wall of the cylinder 40 in the vicinity thereof. Further, the valve balls 49 in the output chambers 45a and 45b are in contact with the rear end 44a of the shaft portion 44, respectively, and the valve balls 49 are press-fitted into the tip recess 50a of the stem 50, so that the stem 50i; i output chamber 45a, A spring 51 in 4.5b urges the valve ball 49 toward the shaft portion 44, and normally the liquid passage 48 is closed. Output chamber 45a, 4.5
b are in communication with the first output boat 18 and the second output boat 25, respectively. The shaft portion 50b of the stem 50 extends into the input chambers 52a, 52b behind the output chambers 45a, 45b, and its end portion is supported by a ball 54 biased by a spring 53. The input chambers 52a and 52b are the first output boat 18 and the second capo 2, respectively.
It communicates with 4.

The dual plunger 4.2a (4, 2b), the valve balls 49, 54, and the stem 50 each constitute a valve mechanism 55, which is one of the features of the present invention.

Next, the operation of the hydraulic pressure control device configured as described above will be explained.

[For normal driving] (1) Plagi pedal (not shown) when the vehicle is running
When you step on the switch valve 12a at the beginning of braking,
takes position A, and the pressure fluid from Musk Schilling lO is
Pipe II, 22, switching valves +2a, +2b.

It is supplied to the wheel cylinders +5a, +5b of the front wheels 14a, +4b through the pipes 13.23, and at the same time, the first and second man capos 1-17, 24 of the hydraulic pressure control valve 16, the manpower chambers 52a, 52b, Output chambers 45a, 45b, first and second
The rear wheel 2 passes through the output boats 18 and 25 and the pipes 19 and 26.
Supplied to the wheel cylinders 21a and 21b of 0a and 20b. As a result, wheels 14a+4b 20a 20
A brake is applied to each b.

(2) The brake fluid pressure increases and the wheels 14a, +4b2
0a20b reaches a predetermined deceleration or slip rate,
If an attempt is made to cross this point, the switching valve 12a12b takes the position C, and the pipes II, +3 and the pipes 22, 23 are placed in a blocked state, and the pipes j3, 27a and the pipes 23, 27
b is communicated.

(3) As a result, the wheel cylinder 1 of the front wheel 14a
5a enters the reservoir 28a through line 13.27a and is applied to the front wheels +4.5a. b wheel cylinder +5
The brake fluid b passes through the pipes 23 and 27b to the reservoir 2.
8b. At the same time, the brake fluid in the wheel cylinder 2]a of the rear wheel 20a is supplied to the pipe I9, the output port 1-18,
Output chamber 45a, input chamber 52a, one-person caboose 17, conduit 1
3.27a into reservoir 28a. Brake fluid in the wheel cylinder 21b of the rear wheel 20b (J pipe 26, output port 25, output chamber 4.5b, input chamber 521
], input boat 24, and flows into reservoir 28b through conduits 23 and 27b. As a result, wheels +4a14.1
), 20a, 20b are released.

(4) Wheels 14a, 14. When the deceleration of line II, 13 .
27a are cut off from each other, and the pipes 22, 23,
27b are also cut off from each other.

As a result, each wheel cylinder 15a, I 5b 2
The brake fluid pressures 1a and 21b should be kept constant.

(5) When the wheels 14a, I41], 20a, 20b are no longer in a sluggish state, the switching valves 12a, +2b are in position A.
I, thereby communicating the master cylinder side and the wheel cylinder side, and by pressurizing the brake fluid from the hydraulic pump 31, the wheels 14a, +4. b, 20a, 20b
The braking force increases again.

(6) The same control is repeated, and when the vehicle reaches the desired speed and stops again, the brake pedal (not shown) is released, and at the same time the wheel cylinder is released.
5a, +51), 21a, and 21b, the brake fluid flows back to the master ring 10 through each pipe, the hydraulic pressure control valve I6, the switching valve 12a12b, etc., and the brake is released. In the above state, the two piping systems are maintained at approximately the same pressure, so the hydraulic pressure control valve 16 does not operate.

The following is the basic operation of the hydraulic pressure control device. Next, a case will be explained in which the coefficient of friction of the road surface on which the vehicle is running differs greatly between the left and right sides.

``If the coefficient of friction of the road surface differs significantly between the left and right sides'' (1) For example, when the coefficient of friction of the road surface is lower on the right side than on the left side, when you start applying the brakes.'' - Same as in the above case. , one switching valve 12a takes the position C first according to the control signal from the control unit, and brake fluid flows from the wheel cylinder 15a20b to the reservoir 28a.
be discharged. As a result, within the hydraulic pressure control valve 16, the hydraulic pressures in the input chamber 52a and the output chamber 45a on the right side decrease. On the other hand, since brake fluid continues to be supplied from the master cylinder 10 to the wheel cylinders 15b20a, a pressure difference occurs between the tip stepped portions 43a, 43a of the plungers 42a, 4.2b of the hydraulic pressure control valve 16.

(2) When this pressure difference exceeds a set value determined by the biasing force of the springs 47, 47, etc., the plungers 42a, 42b move to the right (low pressure side) within the cylinder 40 in accordance with the pressure difference. At this time, the stem 50 on the left side (high pressure side) follows the movement of the plunger 42b due to the biasing force of the spring 51, and moves the cylinder 40 to the right side (low pressure side), and the valve ball 54 on the left side (high pressure side) inputs Room 5
2b and the output chamber 451). As a result, the fluid supply from the master cylinder IO to the boiler cylinder 21a of one of the rear wheels 20a is cut off.

(3) When the plungers 42a, 42b further move inside the cylinder 40 to the right (low pressure side) as the pressure in the input chambers 52a, 45a on the right (low pressure side) decreases in the state of being shut off as described above, the left (low pressure side) The stem 50 on the high pressure side (high pressure side) abuts against the reiner 46 that is locked on the inner surface of the output chamber 451). Next, the valve ball 49 is prevented from following the plunger 42b and moves away from the rear end of the shaft portion 44, and the liquid passage 4
8 is opened, and as a result, the output chamber 4 on the left side (high pressure side)
5b, output capo) 25, reservoir 2 via conduit 26
The brake fluid pressure in the wheel cylinder 21a of the rear wheel 20a communicating with the pipe line 271) on the side 8b decreases.

(4) When the pressure horn difference falls below the set value, plunger 4
2a and 42b move to the left inside the 7 cylinder 40 and return to their original positions, and the valve ball 49 closes the liquid passage 48 of the shaft portion 44 again. As a result, the wheel cylinder 21a of the rear wheel 20a
The brake fluid pressure will rise again.

(5) Due to the action of the hydraulic pressure control valve J6 as described above, the rear wheel 20a on the same side as the front wheel 14a is controlled according to the brake fluid pressure of the front wheel 14a, and is moved to the side where the friction coefficient of the road surface is low. A certain rear wheel 21a is prevented from locking similarly to the front wheel 14a on the same side.

According to this embodiment, the left and right stroke amounts of the plungers 42a, 4.2b are controlled by the valve balls 49, 49 and the reservoir 2.
The valve ball 54.54 can sufficiently perform its function by opening and closing the liquid passages 48.48 communicating with the input chambers 50a and 28b, and by making the minute stroke amount necessary for the valve ball 54.54 to open and close the input chamber 50a50b. It would be possible to effectively prevent various problems that conventional variable volume types had, such as fluid pressure fluctuations in the low pressure system and overstroke of the master cylinder screws and bolts.

"Effects of the Invention" - As explained in detail, according to the hydraulic pressure control device for a skid prevention device of the present invention, the second hydraulic pressure control valve is connected to the high pressure system of the two systems of the X piping. At the same time as cutting off the high-pressure system, we installed a valve mechanism that communicates the wheel cylinder-side conduit and the reservoir-side conduit, which should be depressurized in the high-pressure system. While being able to keep the stroke amount to the minute amount required to open and close only the pipes of the system,
It is possible to effectively reduce the brake fluid pressure in the high-pressure wheel cylinder. As a result, it is possible to effectively prevent various problems that conventional variable-volume type second hydraulic pressure control valves have, such as fluid pressure fluctuations due to volume reduction in the low-pressure system and overstroke of the piston of the master cylinder. It has excellent effects.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention,
FIG. 1 is a piping system diagram of a hydraulic pressure control device for a skid prevention device, FIG. 2 is a sectional view of the structure of a valve device in the same device, and FIG. 3 is a sectional view of essential parts showing a conventional example of the present invention. 14a, 1 0a 2 5a1 16... 31... 32... 55... 4b...Front wheel, Ob...Rear wheel, 5b, 21 a, 2 l b.・・Wheel cylinder,
...valve device (second hydraulic control valve), ...hydraulic pump, ...reservoir, ...valve mechanism.

Claims (1)

[Claims] A first hydraulic pressure control valve that is disposed between the master cylinder and the two systems of X piping and controls the brake hydraulic pressure of the wheel cylinder according to the braking state of the wheels; When reducing brake fluid pressure by controlling the valve,
a reservoir for storing brake fluid discharged from the wheel cylinder via the hydraulic pressure control valve; and a pressure for pressurizing the brake fluid pressure in the reservoir to communicate the master cylinder and the first hydraulic pressure control valve. A liquid pressure pump that returns the liquid to the liquid supply pipe, and a second liquid pressure control valve disposed between the wheel cylinders of a pair of front wheels or a pair of rear wheels, the second liquid pressure control valve comprising: In the skid prevention device hydraulic pressure control device configured to reduce the brake hydraulic pressure of the high-pressure system wheel cylinder according to the hydraulic pressure difference between the two systems of the X piping, the second hydraulic pressure control valve includes two hydraulic pressure control valves. The system is characterized by being provided with a valve mechanism that shuts off the high-pressure line in the system and at the same time connects the wheel cylinder side line where the pressure of the high pressure system is to be reduced with the reservoir side line. Hydraulic pressure control device for skid prevention equipment.