JPS5854288Y2 - Follow-up control braking force multiplier - Google Patents

Description

[Detailed description of the invention] This invention aims to reduce the operating force of the main braking device of a vehicle.
This invention relates to a follow-up control weir braking force multiplier that operates with pressure fluid from a hydraulic supply source driven by a prime mover.

As shown in FIG. 1, the conventional follow-up control weir braking force multiplier is configured as shown in FIG.
Then, a communication hole 7 provided to communicate the upstream chamber 5 and the downstream chamber 6 separated by the piston 4 is closed at the tip of the rod 2, and the pressure in the upstream chamber 5 is transferred to the fluid pressure source 8.
This pressure causes the piston 4 to move to the right in the drawing against the spring 9.

By this movement of the piston 4, the bushing rod 10
moves under pressure at its tip, and a mask cylinder (not shown) connected thereto is actuated with boost.

In the above-mentioned operation, the operating force of the goose rod 100 is fed back to the operating rod 2, and this is transmitted to the operator via the brake pedal 1.

In addition, the downstream chamber 6 may be directly drained,
Generally, via the pressure control valve 11, the other actuator,
For example, it can be connected to the IF'-71J tank half, transmission pulp, main pulp for working machines, etc.

In the conventional follow-up control weir braking force multiplier described above,
When the operating rod 2 is pushed in suddenly to move the piston 4 at a speed faster than the movement speed due to the amount of fluid delivered from the pressure fluid source 8, the pressure in the upstream chamber 5 becomes negative pressure or lower than that in the downstream chamber 6.

In this state, a force pushing back the operating rod 2 is generated via the piston 4, and even if you dare to push the operating rod 2 in this state to move the piston 4, the pressure control for other actuators is not available in the downstream chamber 6. Since the set pressure of the valve 11 exists, an abnormally large force is required to operate the operating rod 2, and if the operating speed of the brake pedal 1 for operating the operating rod 2 is fast, the brake pedal There were times when the operating sensation of 1 became abnormally heavy.

To solve this problem, it would be possible to increase the discharge amount of pressure fluid by increasing the capacity or rotation speed of the pressure fluid source 8, but this would make the pressure fluid source 8 expensive and require a large amount of space in the fluid pressure piping. There are problems such as load acting on it.

The present invention was developed in consideration of the above, and as shown in FIG. Let's communicate.

As a result, when the pressure in the upstream chamber 5 becomes lower than that in the lower 7i side chamber 6, the fluid pressure in the downstream chamber 6 immediately flows into the upstream chamber 5, thereby eliminating the negative pressure generation in the upstream chamber 5 and temporarily reducing the pressure. This prevents the operating force of the operating rod from becoming abnormally heavy.

In addition, in FIG. 2 showing the embodiment of the present invention, the same components as in the conventional example are given the same reference numerals, and the explanation thereof will be omitted.

Since the present invention is as described above, a large braking force multiplier can be used without any problem for high-speed operation even with an inexpensive pressure fluid source with a small output, and performance can be improved without increasing costs. be able to.

[Brief explanation of the drawing]

FIG. 1 is a configuration explanatory diagram showing a conventional example, and FIG. 2 is a configuration explanatory diagram showing an embodiment of the present invention. 1 is the brake pedal, 2 is the operating rod, 3 is the cylinder,
4 is a piston, 5 is an upstream chamber, 6 is a downstream chamber, 7 is a communication hole, 10 is a bushing rod, and 12 is a check valve.

Claims (1)

[Scope of utility model registration request] An upstream chamber 5 that connects the cylinder 3 to a pressure fluid source 8 and a downstream chamber 6 are partitioned by a piston 4, and a communication hole 7 is provided in the piston 4 so as to communicate the upstream chamber 5 and the downstream chamber 6. , an operating rod 2 operated by the brake pedal 1 is opposed to this communicating hole I, and by moving this operating rod 2 in a direction to close the communicating hole 7, the piston 4 is actuated by the pressure of the upstream chamber 5. The upstream side chamber 5 and the downstream side chamber 6
A follow-up control weir braking force multiplier device, characterized in that these are communicated with each other via a check valve 12 that allows flow only from the downstream chamber 6 side.