JPH0343093Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is a brake control device, for example, a brake control device equipped with a hydraulic control valve with a fail-safe function that is integrally attached to a tandem-type master cylinder. Regarding.

(Prior Art) As a conventional brake control device, there is, for example, one shown in FIGS. 3 to 5 proposed in Japanese Patent Laid-Open No. 61-6056. In Fig. 3, 1 is a brake control device, and the brake control device 1 controls the brake fluid in a reservoir tank 2 provided at the upper part of the brake control device 1, which is provided below the reservoir tank 2 as shown in Figs. 3 and 4. The fluid is pressurized by the master cylinder 3 and sent to a front wheel cylinder (not shown), and the fluid pressure is adjusted and reduced by the fluid pressure control valve 5, and the fluid is sent to a rear wheel cylinder (not shown). A secondary piston 8 and a primary piston 9 are installed in the housing 6 of the master cylinder cylinder 3 with a primary hydraulic chamber 7 interposed therebetween.
is stored. 12 is a return spring.

The hydraulic pressure control valve 5 is installed in the housing 6 at the upper side of the master cylinder 3, as shown in FIG. It is fixed integrally. A stepped piston 15 is located inside the hydraulic pressure control valve 5.
A poppet valve 16 is housed therein, and a tip 16a of the poppet valve 16 projects into the housing 6 through the liquid discharge port 14. The step piston 15 is moved by the hydraulic pressure acting on both ends thereof, and has a pressure reducing function of opening and closing the liquid passage 17 together with the poppet valve 16 to reduce the liquid pressure. Engagement member 19
When the front brake system fails, it senses the stroke of the secondary piston 8, moves to the left in the figure together with the secondary piston 8, and engages the engaging member 1.
The other end 19b of 9 is the tip 1 of the poppet valve 16.
6a to displace the poppet valve 16, thereby opening the liquid passage 17 and limiting the pressure reducing function.

(Problems to be solved by the invention) However, the conventional brake control device 1 has the following problems:
In order to remove the air accumulated in the upper part 7a of the primary hydraulic pressure chamber 7, as shown in FIG. The hydraulic pressure control valve 5 must be provided so that the angle between the axis P of the valve hole 16b that accommodates the poppet valve 16 of the control valve 5 and the vertical line N is a small acute angle. Therefore, there is a problem in that the hydraulic pressure control valve 5 and the reservoir tank 2 interfere with each other, and the reservoir tank 2 needs to have a special shape. There is also the problem that the setting angle of the axis P of the hydraulic pressure control valve 5 is limited.
A further problem is that sometimes a special bleeder is required to bleed air.

Therefore, the present invention provides a brake control device in which the hydraulic pressure control valve of the brake control device can be set over a wide range without interfering with the reservoir tank, and which does not require special parts such as a bleeder for air venting. The purpose is to

(Means for Solving the Problems) The brake control device according to the present invention has a pressure reducing function by sensing the stroke of the secondary piston and displacing the poppet valve of the hydraulic pressure control valve integrally provided with the master cylinder. The brake control device is characterized in that an air vent hole is provided that communicates the upper end of the piston hole and the side end of the valve hole.

(Function) The brake control device of the present invention is provided with an air vent hole that communicates the upper end of the piston hole with the side end of the valve hole. , and even if the opening of the valve hole is located at the center side, it moves from the upper end of the piston hole through the air vent hole to the side end of the valve hole, and then moves outward along the slope of the hydraulic control valve. is released. For this reason, the axis of the valve hole, that is, the axis of the hydraulic pressure control valve, can be arranged from a nearly horizontal position to a conventional inclined position where air is more easily discharged, and the hydraulic control valve can be set in a wide range of positions. margin increases significantly.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

1 and 2 are diagrams showing an embodiment of a brake control device according to the present invention.

First, the configuration will be explained. In FIG. 1, 21 is a brake control device, and the brake control device 21 is shown pressurizing brake fluid in a reservoir tank 22 provided above by a master cylinder 23 provided below the reservoir tank 22. In addition, the hydraulic pressure is adjusted and reduced by the hydraulic pressure control valve 25 (shown at the bottom of the drawing for ease of understanding) and transferred to the rear wheel cylinder (not shown) via the brake tube. and pressure-fed each. A secondary piston 28 and a primary piston 29 are accommodated in a piston hole 26 a in a housing 26 of the master cylinder 23 via a primary hydraulic pressure chamber 27 . 30 is a return spring.

As shown in FIG. 2, the hydraulic pressure control valve 25 is integrally fixed to the housing 26 on the side of the master cylinder 23 and separated from the reservoir tank 22. At this time, the upper end 26b of the piston hole 26a
and the side end 32a of the valve hole 32 are the air vent hole 3.
It is connected by 3. A valve hole 32 in the hydraulic pressure control valve 25 communicates with the primary hydraulic pressure chamber 27 via a liquid discharge port 34 formed in the housing 26 . A step piston 35 and a poppet valve 36 are housed in the hydraulic control valve 25, and the poppet valve 3
The distal end 36a of 6 protrudes into the housing 26 via the liquid discharge port 34.

The stepped piston 35 is moved by the hydraulic pressure acting on both ends thereof, and has a pressure reducing function of opening and closing the liquid passage 37 together with the poppet valve 36 to reduce the liquid pressure.

The engaging member 39 has one end 39a locked to the secondary piston 28. When the front brake system fails, it senses the stroke of the secondary piston 28 and moves to the left in the figure together with the secondary piston 28, and the other end 39b of the engagement member 39 on the primary piston 29 side is connected to the tip 36a of the poppet valve 36. When engaged, the poppet valve 36
By displacing the liquid passage 37, the liquid passage 37 is opened and the pressure reducing function is restricted.

Next, the effect will be explained.

The brake control device of the present invention has piston hole 26a.
Since the air vent hole 33 is provided so that the upper end portion 26b and the side end portion 32a of the valve hole 32 communicate with each other, the air accumulated in the upper end portion 26b of the piston hole 26a passes through the substantially horizontal air vent hole 33. The hydraulic pressure control valve 2 is moved to the side end 32a of the valve hole 32.
It is released to the outside along the slope of 5. The substantially horizontal air vent hole 33 is located at the upper end 2 of the piston hole 26a.
6b, the air vent hole 33 further has an air venting function in a large angular range where the air vent hole 33 is inclined in the vertical direction. For this reason, the hydraulic pressure control valve 25
can be installed so as not to interfere with the reservoir tank 22 within this large angle range. Therefore, the degree of freedom in arranging the brake tube connected to the hydraulic pressure control valve 25 can be greatly expanded, and the reservoir tank does not require a special shape. It is easy to do and costs can be reduced. In addition, the hydraulic control valve 25 can be installed in a wide area without using special parts such as a bleeder for air bleed as in the past, and air bleed can be done in one place like the conventional method, and brake control The degree of freedom in the layout of the equipment in the engine room is increased, and the installation range can be greatly expanded.

(Effects) As explained above, according to the present invention, the range in which the hydraulic pressure control valve of the brake control device can be installed in the master cylinder without interfering with the reservoir tank can be greatly expanded.

This makes piping in the engine room of the brake tube connected to the hydraulic pressure control valve easy, and the shape of the reservoir tank is no longer irregular, making it easy to mold and reducing costs. The amount can also be increased. Furthermore, there is no need for special parts such as a bleeder, and air bleeding can be done in one place as in the past, greatly expanding the range in which the brake control device can be installed.

[Brief explanation of the drawing]

1 and 2 are diagrams showing an embodiment of a brake control device according to the present invention, with FIG. 1 being an overall sectional view thereof, and FIG. 2 being a sectional view of a main part thereof. 3 to 5 are diagrams showing conventional brake control devices.
The figure is a plan view thereof, FIG. 4 is a longitudinal sectional view of FIG. 3, and FIG. 5 is a sectional view of a main part thereof. 21... Brake control device, 22... Reservoir tank, 23... Master cylinder, 25... Hydraulic pressure control valve, 26... Housing, 27... Primary hydraulic chamber, 28... Secondary piston, 29...
...Primary piston, 30...Return spring, 32...Valve hole, 33...Air vent hole,
34...Liquid discharge port, 35...Step piston, 36
...Poppet valve, 37...Liquid passage, 39...
Engagement member.

Claims (1)

[Scope of utility model registration request] In a brake control device that limits hydraulic function by sensing the stroke of a secondary piston and displacing a poppet valve of a hydraulic pressure control valve provided integrally with the master cylinder, the upper end of the piston hole and the side of the valve hole A brake control device characterized by having an air vent hole communicating with an end portion.