JPH038980B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a valve device (hereinafter referred to as an auto-stop valve) for maintaining brake fluid pressure when a vehicle (four-wheeled vehicle, two-wheeled vehicle, etc.) is stopped. It is related to.

(Prior Art) Generally, when braking a vehicle, it is better to keep the vehicle stopped until the next time the vehicle moves forward (or backward) to prevent the vehicle from moving unexpectedly. In many cases, a parking brake mechanism is used, such as simply releasing the brake pedal after the vehicle has stopped, or when driving on a slope.

However, such an operation is complicated, and since the parking brake is often not used except on slopes, there is a risk that a stopped vehicle may end up in a state where no braking is applied and cause the vehicle to move unexpectedly.

(Problems to be Solved by the Invention) In view of these points, the inventor of the present invention has proposed that after the vehicle is stopped by performing a braking operation on a vehicle having a hydraulic braking mechanism, that is, a brake operation, the next forward movement of the vehicle ( Until an operation is performed for (or moving backward), the brake system automatically and mechanically maintains the wheel cylinder fluid pressure (brake fluid pressure) in the brake system from the master cylinder to the wheel cylinder. An electromagnetically actuated valve (auto stop valve) is installed in the hydraulic pressure path connecting the brake fluid in the wheel cylinder, and this auto stop valve stops the brake fluid in the wheel cylinder from the vehicle stop operation (brake operation) to the next vehicle oscillation operation. We conducted repeated studies to develop a structure that would maintain and maintain pressure.

An auto-stop valve with such a configuration basically has an input liquid chamber A communicating with the master cylinder,
It is equipped with an output fluid chamber B that communicates with the brake device, a valve mechanism that can open and close communication between these fluid chambers, and an electromagnetic actuation mechanism that can maintain this valve mechanism in a closed state against hydraulic pressure when necessary. However, such auto-stop valves operate repeatedly every time the vehicle stops at a traffic light, etc., and the valve mechanism must have high sealing performance and durability. It is necessary to take into consideration that the brake fluid pressure can be repressurized reliably when the brake fluid pressure is repressurized while a constant fluid pressure is maintained. For these reasons, the present invention uses a so-called ball valve as a valve mechanism in which a valve seat and a ball valve body are brought into contact and separated, and the liquid from input liquid chamber A to output liquid chamber B during repressurization is An auto-stop valve characterized by using a unidirectional liquid flow permitting means, preferably a piston cup type sealing member, as a mechanism to ensure the flow, and further by reducing the electromagnetic actuation force required to maintain the liquid pressure as much as possible. It was developed.

(Means for Solving the Problems) The auto stop valve of the present invention that achieves these objects is characterized by an input fluid chamber A communicating with the master cylinder and an output fluid chamber B communicating with the brake device.
a seat member slidably fitted to the inner circumferential surface of the cylinder so as to partition the inner circumferential surface of the cylinder, a movable locking means for locking the movement of the seat member toward the input liquid chamber, and a space between the seat member and the inner circumferential surface of the cylinder Assembled input liquid chamber A
a unidirectional sealing means that allows pressure fluid to flow from the input fluid chamber A to the output fluid chamber B but prevents pressure fluid flow in the opposite direction; A communication flow path that communicates the liquid chamber B, a ball seat surface provided as an opening of this communication flow path to the input liquid chamber A, and a ball disposed facing the ball seat surface so as to be pushed by a spring force. and an electromagnetic actuation mechanism that applies a moving force to the ball using electromagnetic force to bring it into contact with the ball seat surface, and a spring that separates the ball seat surface and the ball under normal conditions, and the operation of the electromagnetic actuation mechanism when the vehicle is stopped. The configuration is such that communication between the input liquid chamber A and the output liquid chamber B is cut off.

(Example) The present invention will be described below based on comparative examples and examples shown in the drawings.

Comparative Example In FIG. 1, a cylindrical sleeve 1 has a large-diameter head 1a formed at one end, and a threaded portion 1b is provided at the other small-diameter end, into which a nut member 2 is screwed. It will be worn. A housing case 4 containing a solenoid 3 is fitted onto the outer periphery of the sleeve 1 and fixed by tightening the nut member 2.

Further, a plug 5 is screwed onto the open end side of the nut member 2. A port 6 of the plug 5 communicates with a brake device (not shown), and a port 7 formed in the sleeve head 1a communicates with a master cylinder (not shown).

A seat member 8 for configuring a valve mechanism and an armature 13 for configuring an electromagnetic actuation mechanism are housed inside the cylinder of the sleeve 1, and the former is connected to a piston cup 9 attached to its outer circumference. The inside of the cylinder is divided into input and output liquid chambers A and B, and the armature 13 is located within the input liquid chamber A.

The piston cup 9 allows pressure fluid to flow from A to B.

The structure of the valve mechanism is such that a flow path 8a communicating between the input and output liquid chambers A and B is formed in the shaft of the seat member 8, and a conical ball seat surface 8b is formed at the opening to the B liquid chamber. is formed, and a ball 10 is placed opposite this seat surface 8b. The ball 10 is biased by a hold spring 11 attached to the seat member 8 with a spring force that causes it to move away from the seat surface 8b, and is pressed against the tip of the inner end protrusion of the plug 5.

12 is an armature 1 in which the sheet member 8 will be described later.
This is the first set spring to be set at a predetermined position during non-operation together with the second set spring 14 attached to 3, and the spring force of these set springs may be set to a small value.

The armature 13, which constitutes the driving part of the electromagnetic actuating mechanism, moves so as to press and move the seat member 8 against the first set spring 12 and the hold spring 11 by the excitation of the solenoid 3 (moves to the left in the figure). ), and normally the seat member 8 is moved in the same direction via the poppet 15 supported by the second set spring 14 so as not to set the distance between the seat surface 8b of the seat member 8 and the ball 10 too large. Pressing lightly.

Next, its operation will be explained.

In this comparative example, the solenoid 3 is energized in response to a predetermined electrical command several seconds after the vehicle has stopped due to a vehicle braking control operation, for example, and is energized for the next vehicle starting (or reversing) operation, such as connecting the clutch. The solenoid is controlled so that it continues to be energized until it is operated, but in the case of so-called automatic vehicles, the solenoid may be de-energized by pressing down on the accelerator pedal. It is sufficient to maintain the brake fluid pressure before the operation is released and to set the control so as not to interfere with the next vehicle starting operation, and various suitable controls can be selected depending on the nature and model of the vehicle.

Here, in the initial stage when the brake fluid pressure is transmitted through the auto-stop valve in the illustrated state, the hydraulic pressure in the axial direction acts in a balanced manner on the armature 13, so the armature 13, the seat member 8, and especially the seat of this seat member 8 The relationship between the surface 8b and the ball 10 is maintained as shown, and the fluid chambers A and B are in communication, so that brake fluid pressure is transmitted directly from the master cylinder to the foil cylinder.

In this state, when the vehicle speed decreases and the solenoid 3 is energized after stopping, the armature 13 is pressed to the left in the figure, and the seat member 8 is therefore pressed to the left in the figure, and the seat surface 8b is It comes into contact with the ball 10, and the output fluid chamber B, that is, the brake fluid pressure, is maintained at the fluid pressure state at that time.

Needless to say, when the solenoid 3 is de-energized, the initial state is restored.

Note that if the master cylinder side is re-pressurized while the hydraulic pressure is maintained in the output liquid chamber B, this pressurized liquid will flow in one direction of the piston cup 9 if it exceeds the hydraulic pressure value in the output liquid chamber B. Depending on the sealing performance, the output liquid chamber B
This will cause the brake fluid pressure to increase.

However, the brake pedal is normally released from being depressed until the next start operation after the solenoid 3 is energized, but in this case, in the configuration of this comparative example, the seat member 8 is actuated from the brake device side. The electromagnetic force generated by the solenoid must be strong enough to overcome the hydraulic pressure.

Embodiment FIG. 2 shows an embodiment of the present invention, and the comparative example in FIG.
0' are arranged in the opposite manner, and these are further arranged in the cylinder of the ball iron core 16 which is inserted and fixed into the cylinder of the sleeve 1, but the other configuration is the same as the comparative example. is doing. Therefore, common members are given the same reference numerals, and their explanations are omitted.

In this example, the abutment moving force applied to the ball 10' from the armature 13 via the poppet 15 to the seat surface 8b is a force that moves the seat member 8' to the left in the figure via the hold spring 11. Therefore, in order to regulate this, the spring force of the first set spring 12 is set large, and accordingly, the seat member 8' is prevented from moving to the right in the figure. It is configured to be locked by engaging with the stepped shoulders 17 of 16.

According to the configuration of this example, the same operation as that of the comparative example can be obtained, and automatic and mechanical brake fluid pressure maintenance can be achieved when the vehicle is stopped at an intersection or the like.

In addition to this, the present example also has the advantage that the electromagnetic force is relatively small. In other words, brake fluid pressure (hydraulic pressure in output fluid chamber B)
When the hydraulic pressure in the input liquid chamber A becomes zero (the pedal is released) in the holding state, the hydraulic pressure acts on the seat member 8' only in the right direction in the figure. Since the movement of the member 8' in the same direction is restricted by the stepped shoulder 17 of the pole iron core as described above, this imbalance in hydraulic pressure is not related to electromagnetic force.
In the end, it is sufficient that the electromagnetic force is capable of resisting the hydraulic pressure of a small area acting on the ball 10'.

(Effects of the Invention) As described above, according to the auto-stop valve of the present invention, it is possible to automatically maintain the braking force when the vehicle is stopped in a normal vehicle or a so-called automatic vehicle, and furthermore, this braking force can be maintained automatically when the vehicle is stopped. This structure has the advantage that the electromagnetic force required to maintain the structure is sufficiently small compared to the structure of the comparative example, and its usefulness is extremely large.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the structure of an auto-stop valve according to a comparative example, and FIG. 2 is a sectional view of the auto-stop valve for explaining an embodiment of the present invention. 1... Sleeve member, 1a... Head, 1b...
Threaded portion, 2... Nut member, 3... Solenoid,
4...Housing case, 5...Plug, 6,7
...Port, 8, 8'... Sheet member, 8a, 8
a'...Flow path, 8b, 8b'...Seat surface, 9...Piston cup, 10, 10'...Ball, 11...
...Hold spring, 12...First set spring, 13...Amateur, 14...Second set spring, 15...Poppet, 16...Pole iron core.

Claims (1)

[Claims] 1. A seat member that is slidably fitted to the inner peripheral surface of the cylinder to partition an input fluid chamber A that communicates with the master cylinder and an output fluid chamber B that communicates with the brake device, and a seat member that is slidably fitted to the inner circumferential surface of the cylinder so as to partition an input fluid chamber A that communicates with the master cylinder and an output fluid chamber B that communicates with the brake device. A movable locking means for locking, and a movable locking means assembled between the sheet member and the inner peripheral surface of the cylinder to move the liquid from the input liquid chamber A to the output liquid chamber B.
a unidirectional sealing means that allows pressurized liquid to flow in the opposite direction but prevents the pressurized liquid from flowing in the opposite direction; A communication flow path, a ball seat surface provided as an opening of the communication flow path to the input liquid chamber A, and a ball disposed facing the ball seat surface so as to be pushed by a spring force, and an electromagnetic force. It includes an electromagnetic actuation mechanism that applies a moving force to the ball to bring it into contact with the ball seat surface, and a spring that separates the ball seat surface and the ball in normal conditions, and the input liquid chamber A is activated by the operation of the electromagnetic actuation mechanism when the vehicle is stopped. An auto stop valve for a vehicle, characterized in that it is configured to cut off communication between the output liquid chamber B and the output liquid chamber B.