JPH0226768Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a brake hydraulic pressure control device used in a vehicle braking system, which reduces input hydraulic pressure at a constant rate to obtain output hydraulic pressure.

This brake fluid pressure control device applies the same braking force to the front and rear wheels when the braking force is low at the beginning of braking, and when the braking force reaches a predetermined level, the braking force on the rear wheels is made smaller than that on the front wheels. It is designed to lock the front and rear wheels at the same time, and for this purpose, a plunger that responds to the master cylinder pressure opens and closes the valve, and by opening and closing the valve, the master cylinder pressure is reduced at a predetermined rate to lock the rear wheel cylinder. We are making it possible to communicate to.

In such a brake hydraulic pressure control device, a valve mechanism, a plunger, etc. are housed in a substantially cylindrical bottomed housing for the purpose of simplifying the overall configuration, improving ease of assembly, and ease of installation. A so-called cartridge type brake hydraulic pressure control device has been proposed in which the assembled housing can be screwed or fitted in a detachable manner directly to a master cylinder.

However, in this type, the support part of the valve body disposed on the output side of the plunger corresponds to the axis of the bottomed part of the housing, so the structure makes it difficult to This makes it difficult to set the output port on the same axis as the plunger in the housing. This is not only complicated in construction, but also inevitably increases in size, and is accompanied by inconvenience in terms of piping.

In view of the above points, the present invention has a plate-like shape in which an output port is set coaxially with the plunger axis, and a protruding portion is provided on the periphery of the node of the housing shaft hole formed adjacent to the output port. A retainer is inserted, the retainer is fitted into the shaft hole so that the overhanging portion presses against the wall of the shaft hole, and the retainer is biased from the abutting portion of the valve body that comes into contact with the retainer, thereby producing the above output. A through hole communicating with the hole is formed, and this is an attempt to solve the above-mentioned problems.

The present invention will now be described with reference to the illustrated embodiment. In FIG. 1, a valve housing 1 consists of a single, generally cylindrical member, the base end of which is fitted into a mounting hole 3 provided in a casing 2 of a master cylinder. It is screwed on. The large diameter portion 4a of the plunger 4 is slidably fitted into the shaft hole 5 of the valve housing 1, and a node 6 forming the bottom of the shaft hole 5 can regulate the insertion end of the plunger 4. will be provided. An output port 7 is formed coaxially with the shaft hole 5 at the distal end of the valve housing 1, and communicates with the shaft hole 5 through the center hole 7a of the joint portion 6.

The plunger 4 includes a small diameter part 4b connected to the large diameter part 4a.
A seal member 9 is fitted liquid-tightly into the peripheral wall of the mounting hole 3.
The protruding portion 4c thereof is opposed to the bottom wall 3a of the mounting hole 3. Further, a stepped portion 4b connecting the small diameter portion 4b and the large diameter portion 4a,
A spring 11 is installed between the retainer 8,
The plunger 4 is biased toward the joint portion 6, thereby making it possible to maintain the initial position of the plunger before the start of pressure reduction, as is well known. Reference numeral 10 denotes a retaining ring attached to the protruding portion 4c of the small diameter portion 4b, leaving a sliding margin for the retaining ring.When removing the assembly as a brake hydraulic pressure control device from the mounting hole 3 of the master cylinder 2, the retaining ring 10 is attached to the protrusion 4c of the small diameter portion 4b. Consideration is given so that the member 9 can also be removed all at once.

A valve body 1 is provided in a valve chamber 12 formed at the end of the large diameter portion 4a and communicating with the shaft center passage 4e of the plunger 4.
3 is accommodated, and this valve body 13 is always urged toward the node 6 side by a spring 14 interposed between this and the bottom of the valve chamber, and the small diameter end 13a of the valve body 13 is connected to the valve chamber 12. An annular valve seat 17 fitted to the opening side of the valve is loosely inserted and protrudes.

A retainer 15 that restricts the protruding end of the valve body 13 is fitted into the bottom of the shaft hole of the valve housing 1, that is, the joint portion 6. This retainer 15
As shown in FIGS. 2a, b, and c, the radial projecting portion 15a is made of an elastic plate member and is formed integrally with the periphery of a circular bottom plate to be fitted into the bottom of the shaft hole. The projecting portions 15a are bent laterally from the circular bottom plate and kept in a slightly outwardly inclined manner, and when the retainer 15 is inserted into the housing shaft hole, each of these projecting portions 15a
comes into elastic contact with the peripheral wall of the shaft hole to maintain a good fit within the shaft hole. In addition, a plurality of through holes 15b are bored in the circular bottom plate of the retainer 15 at positions offset from the contact portion 15c with which the small-diameter end 13a of the valve body 13 comes into contact with the force of the spring 14. This allows the inside of the valve chamber 12 to communicate with the output port 7 through the center hole 7a of the node 6 when the valve body is opened.

In the device of this embodiment having the above-described configuration, when the plunger 4 is not in motion, the plunger 4 is urged by the spring 11 and comes into contact with the retainer 15, and the valve body 13 also comes into contact with the retainer 15 and is removed from the valve seat 17. He is away from his seat. Therefore, the pressure oil input from the master cylinder 2 is directly guided to the output port 7 through the passage 4e, the valve chamber 12, and the through hole 15b of the retainer 15, and is supplied to the rear wheel cylinder. When the input hydraulic pressure from the master cylinder 2 rises above a certain value, the plunger 4 resists the spring 11 because the pressure receiving area of the end face of the large diameter part 4a of the plunger 4 is larger than the pressure receiving area of the end face of the protruding part 4c. and go to the right.
Note that the amount of rightward movement is regulated by the protrusion 4c coming into contact with the bottom surface 3a of the attachment hole 3. on the other hand,
Since the valve body 13 is biased by the spring 14, it approaches the valve seat 17 relatively and is seated on it, so that the passage of the pressure oil toward the output port 7 side is blocked, and the rise in output hydraulic pressure is prevented. Stop. However, when the input hydraulic pressure further increases, the plunger 4 receives this hydraulic pressure and moves to the left, and the valve body 13 comes into contact with the retainer 15 and returns to the valve seat 17.
The hydraulic pressure introduced into the output port 7 rises again. When this hydraulic pressure further increases, the plunger 4 moves to the right, and by repeating the above operation, it is possible to obtain an output hydraulic pressure that reduces the input hydraulic pressure by a predetermined ratio. Note that while the hydraulic pressure guided to the rear wheel cylinder is controlled to be reduced by the above-described operation, the hydraulic pressure of the master cylinder is directly guided to the front wheel cylinder via the other output port 18.

Since the device of this embodiment has the above-mentioned configuration, it is a so-called cartridge type device, and is equipped with a configuration that allows the plunger to move forward and backward with respect to the valve body held on the end wall of the housing. , the output port cannot be placed on the axis of the housing,
In contrast to this, which was undesirable in terms of workmanship or piping, as described above, according to the present device, the retainer 15 is fitted into the node 6 in the shaft hole 5, and the valve body 13 is placed in contact with the retainer 15. Since the through hole 15b is provided offset from the contact portion 15c, it is possible to form a flow path for the output hydraulic pressure while ensuring the supporting position of the valve body 13. Therefore, the output port 7 can be connected to the plunger. This allows it to be set coaxially with the axis. Moreover, this retainer 15 can be easily manufactured by pressing the plate, and when fitting, the overhanging portion 15 is brought into elastic contact with the wall of the shaft hole, thereby ensuring a secure and firm fitting. can be made to take.

Further, according to this device, while the output port can be set on the housing axis as described above, when assembling the device as a cartridge type device, first the retainer is inserted into the shaft hole 5 of the valve housing 1. 15 was press-fitted, the plunger 4 with the valve body 13 attached thereto was inserted and assembled together with the spring 11, and the annular retainer 8 fitted into the end of the plunger 4 was caulked with the thin-walled cylindrical portion 1a at the end of the housing. Later, a seal member 9 is attached to the tip of the plunger 4.
By attaching the retaining ring 10, it is possible to easily assemble a so-called cartridge-type device assembly that can be integrally attached to and detached from the attachment hole 3 of the master cylinder 2.

In the above embodiment, the retainer 15 is provided with the projecting portions 15a in a radial manner.
Although configured as an elastic piece that can make elastic contact with the wall of the shaft hole, the above-mentioned projecting portions 15a may be configured as a cylindrical body that connects with each other and expands slightly outward. . Furthermore, it goes without saying that the manner in which the through holes 15b are installed can be offset from the abutting portion 15c and various shapes, numbers of holes, etc. can be selected.

As described above, according to the present invention, by providing a retainer having a through hole in the node in the housing shaft hole, the output port can be set coaxially with the plunger axis, and the cartridge type brake fluid can be used. The present invention has the advantage that it is useful for making the pressure control device more compact and simple, and that the above-mentioned effects can be achieved with a simple structure in which only a retainer is fitted, which is easy to manufacture and can be installed reliably.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figures show a retainer fitted into the housing shaft hole, FIG. 2a is a plan view thereof, and FIG. 2b is a second
FIG. 2c is a longitudinal sectional view taken along the line B-B' in FIG. 2a, and a perspective view in FIG. 1...Housing, 2...Master cylinder,
4... Plunger, 5... Shaft hole, 6... Joint, 7
... Output port, 12 ... Valve chamber, 13 ... Valve body, 15
...retainer, 15a ... overhang, 15b ... through hole.

Claims (1)

[Scope of utility model registration request] A cylindrical housing that can be attached to a master cylinder, a plunger that is slidably fitted into an axial hole of the housing and has one end of an axial passage communicating with the master cylinder, and a valve at the other end of the passage in the plunger. a valve body for opening and closing the valve chamber provided indoors; the plunger is moved forward and backward by input hydraulic pressure from a master cylinder to open and close the valve body;
In the braking hydraulic pressure control device that supplies a reduced output hydraulic pressure corresponding to the input hydraulic pressure from the output port of the housing to the wheel cylinder, the output port is provided coaxially with the plunger axis, and the output port is provided adjacent to the output port. Inside the joint having the hole of the formed housing shaft hole,
A projecting portion provided on the periphery is pressed against the wall of the shaft hole to fit a plate-shaped retainer, and the valve body elastically supported by the plunger is brought into contact with the retainer, and the corresponding contact portion A brake hydraulic pressure control device characterized in that the retainer is provided with a through hole which is offset from the retainer and communicates with the output port.