JPH0144381Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a hydraulic pressure regulating valve used in a two-way braking hydraulic pressure circuit of a vehicle.

In hydraulic brake systems for vehicles, especially automobiles, in order to properly distribute the braking force between the front and rear wheels, after the hydraulic pressure supplied from the master cylinder exceeds a certain value (pressure reduction start pressure), A hydraulic pressure regulating valve is used that reduces the hydraulic pressure supplied to the rear wheels proportionally to the input hydraulic pressure.

There are various types of such hydraulic pressure regulating valves, but from the standpoint of automobile safety, the piping system from the master cylinder to the brakes is divided into two systems.
What is used in the so-called diagonal split brake system, which connects the right front wheel and left rear wheel to one system, and the left front wheel and right rear wheel to the other system, is as follows:
In order to ensure sufficient braking power, when one hydraulic system fails, the system has a "failure compensation function" that stops the pressure reduction in the other system and supplies the rear wheels with the same hydraulic pressure as the front wheels. It is desirable that there be.

In line with this requirement, this type of hydraulic pressure regulating valve has been actively developed for some time, and among them, the valve shown in FIG. 1, which was proposed earlier by the applicant, has a simple structure, good performance, and low manufacturing cost. It also has the advantage of being inexpensive. This hydraulic pressure regulating valve has two input ports 1,
1' and an output port 2, 2' that communicates with each input port individually, a hollow piston 5 fluid-tightly inserted into a cylinder 4 that connects both hydraulic circuits, and a coaxial valve of the main body 3. Lip seals 7, 7' engage with seats 6, 6' formed symmetrically on the upper side.
A pair of plungers 9, 9' whose rear ends are liquid-tightly guided by the piston 5 and which bring the front valve heads 8, 8' into contact with the lip seals 7, 7' to reduce pressure, and inside the piston 5, both The set spring 11 is interposed between spring retainers 10 and 10' engaged with the plungers 9 and 9', and biases each plunger in the opposite direction, that is, in the direction in which the passage is always open. The operation when the hydraulic pressures P _M and P _M ' supplied to the input ports 1 and 1' are constant values (this pressure is P _N , the load of the spring 11 is F, and the small diameter of the plunger inserted into the piston 5 is If the cross-sectional area of the part is S, then P _N =F/S)
When the pressure is exceeded, the spring 11 is compressed and the plungers 9, 9' move toward each other, and a pressure reducing action is started.

On the other hand, if one of the hydraulic pressure circuits fails, that is, if the right hydraulic system fails, the input hydraulic pressure P _M =0, so the hydraulic pressure acting on the piston 5 Piston 5 is out of balance.
is pushed to the right, and this movement is transmitted to the plunger 9 via the snap spring 13, so
When the force pushing the piston 5 to the right becomes greater than the set load of the spring 11, the piston 5 and plunger 9 compress the spring 11 and move to the right until the piston comes into contact with the stopper 12' of the main body. In this process, the plunger 9
When the valve head 8 passes through the lip seal 7, the pressure reducing function disappears, and even if the input hydraulic pressure P _M rises above the normal pressure reducing action start pressure, the relationship P _M = P _R (output hydraulic pressure) is maintained. It will be done. If the other hydraulic system fails (P _M =0), the piston 5 comes into contact with the stopper 12 on the opposite side, and P _M '=P _R '.

The hydraulic pressure regulating valve described above transmits the movement of the piston to the plunger via a snap ring, but if this method is adopted, two snap springs are required, and the assembly is done with respect to the shaft. Since it is carried out from the side, a holding sleeve 14 is also necessary. Therefore, the cost increases accordingly, the assembly requires more effort, and the axial dimensions of the plunger and the valve body also become longer.

This idea solves the above problems and improves processability.
It is an object of the present invention to provide a hydraulic pressure regulating valve that is easier to assemble and can also be reduced in axial dimension.

This idea involves caulking and fixing a spring retainer that engages with the rear end of the plunger inside the piston, and transmitting the movement of the piston to the plunger through this retainer.
The feature is that the conventionally required snap spring and sleeve are omitted.

The spring retainer is fixed by gradually tapering the rear end of the plunger 9 and fitting the cap-shaped retainer 10 with one end surface of the bottom wall 10a in contact with the first step 9a, as shown in FIG. 2a. Next, as shown in FIG. 3B, a part of the second step 9b is compressed and deformed to form a caulked portion 9c, or as shown in FIG. 3A, the plunger 9 is formed with a step 9a.
Although it is preferable to use one of the methods in which the retainer 10 provided with the slit 10b and provided with spring elasticity is fitted somewhat tightly, there is no need to be concerned with this method, and other known methods may be used. The purpose of the invention is achieved. It goes without saying that the spring retainer 10' is also fixed in the same manner as described above.

Next, FIG. 4 shows an example of the hydraulic pressure regulating valve of the present invention employing the caulking structure shown in FIG. 2. This valve is formed by dividing the piston 5 into two in order to assemble the spring 11 and attach the retainers 10, 10'.
Before joining the two members, the plunger 9,
The spring retainers 10, 10' are fixed to each plunger by inserting the spring retainers 9' into each plunger, and then the spring 11 is interposed between both retainers, and the divided pistons are press-fitted and integrated.
The plug 15 supporting the other lip seal 7 is attached to the opening of the valve body in a fluid-tight manner.

Here, if the piston 5 is divided into two parts as in the embodiment, the workability during assembly is excellent, but it may be divided into two or more parts as shown in FIG.

Note that the other configurations of the embodiment are basically the same as those shown in FIG. 1, and therefore, the same reference numerals are given to the figures and the explanation thereof will be omitted. Also, its operation is the same as the previous one, except that the movement of the piston is transmitted to the plungers 9, 9' via the spring retainers 10, 10', so a description thereof will also be omitted.

As explained above, in the present invention, the spring retainer is caulked and fixed to the plunger, and the movement of the piston that moves when one system fails is transmitted to the plunger via this retainer, so that the spring retainer is fixed to the plunger. Two snap springs and a sleeve are omitted, which improves machinability, ease of assembly and economy, and reduces the axial dimensions of the plunger and valve body.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional hydraulic pressure regulating valve, and Figs. 2 and 3 show an example of the mounting structure of a plunger and a spring retainer.
4 is a perspective view of the valve before assembly, b is a perspective view of the valve after assembly, and FIG. 4 is a sectional view showing an example of the hydraulic pressure regulating valve of this invention. 1, 1'... Input port, 2, 2'... Output port, 3... Valve body, 5... Piston, 7, 7'...
...lip seal, 9,9'...plunger, 10,
10'... Spring retainer, 11... Set spring, 9a, 9b... Stepped portion, 9c... Caulked portion, 10a... End wall, 10b... Slit.

Claims (1)

[Scope of utility model registration request] A valve body with two input/output ports, a pair of lip seals arranged symmetrically on the same axis inside the body, a plunger that abuts the valve head against these seals to reduce pressure, and a plunger inside the valve body. It consists of a piston that is inserted into the cylinder and fluid-tightly guides the rear end of the plunger, and a set spring that is interposed between the retainers that engage each plunger and bias each plunger in opposite directions. A two-system hydraulic pressure regulating valve that deflects the piston to the failed side when the hydraulic pressure circuit fails, and transmits the movement to the plunger in the normal circuit, so that the valve head of the plunger passes through the lip seal. A two-system controlled hydraulic pressure regulating valve characterized in that the spring retainer is fixed to the plunger, and the movement of the piston is transmitted to the plunger via the retainer.