JPH078935Y2 - Proportional electromagnetic pressure control valve that can continuously control pressure from negative pressure to positive pressure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a proportional electromagnetic pressure control valve for controlling an output pressure from a negative pressure to a positive pressure by an electromagnetic driving force proportional to an energization amount.

[Prior Art] An electromagnetic section having a proportional solenoid and a valve section provided with a valve member whose flow passage opening is controlled by driving the proportional solenoid. A proportional electromagnetic pressure control valve that applies a proportional electromagnetic driving force and an acting force of fluid pressure fed back from an output port is already known.

However, the above-mentioned known proportional electromagnetic pressure control valve targets positive pressure as the output pressure, and cannot be controlled particularly when the output pressure ranges from negative pressure to positive pressure.

Therefore, when the output pressure of the working fluid fluctuates from negative pressure to positive pressure, a complicated circuit configuration for controlling the output pressure is required, such as switching between multiple proportional electromagnetic pressure control valves by some means. And

[Problem to be Solved by the Invention] The problem to be solved by the present invention is to enable control of output pressure ranging from negative pressure to positive pressure with one proportional electromagnetic pressure control valve, To expand the area of use.

[Means for Solving the Problems] In order to solve the above problems, a proportional electromagnetic pressure control valve of the present invention controls an opening of a flow passage by an electromagnetic unit having a proportional solenoid and a drive by the proportional solenoid. A proportional solenoid type pressure control valve comprising a valve portion provided with a spool, wherein an electromagnetic driving force proportional to an energization amount of a proportional solenoid and a fluid pressure acting force fed back from an output port act on the spool. The valve body is provided with a positive pressure port communicating with a positive pressure source, a negative pressure port communicating with a negative pressure source, and the output port communicating with a load, and the spool with the electromagnetic driving force of a proportional solenoid, The action force of the fluid pressure fed back to the feedback chamber and the urging force of the spring are caused to act in opposition to each other,
The spool that moves depending on the magnitude of these forces enables the output port to be switched between the positive pressure port and the negative pressure port, and the biasing force of the spring is generated when the negative maximum feedback action force acts on the feedback chamber. The size of the spool is such that it moves to a position where the output port and the negative pressure port communicate with each other at the maximum opening, and the spool is made to communicate with the output port from the negative pressure port to the positive pressure port depending on the magnitude of the electromagnetic driving force. There is.

[Operation] When the electromagnetic portion is not excited, the spool is in a position where the output port and the negative pressure port communicate with each other at the maximum opening due to the biasing force of the spring. In this case, since the biasing force of the spring is larger than the negative acting force of the feedback chamber due to the negative pressure, the spool is held in this state.

When the electromagnetic portion is energized, the spool slides toward the feedback chamber due to the driving force proportional to the amount of energization.

In this case, when the energization amount is small, the electromagnetic driving force is small, so that before the spool slides to the position where the output port and the positive pressure port communicate with each other, the electromagnetic driving force and the acting force of the feedback chamber Since the urging force of the spring is balanced, the pressure at the output port is a negative pressure according to the amount of electricity.

When the energization amount of the electromagnetic section is large, the spool slides to the position where the output port communicates with the positive pressure port, and the electromagnetic driving force and the action force of the fluid pressure in the feedback chamber and the biasing force of the spring are balanced. As for the pressure of the output port, a positive pressure corresponding to the amount of electricity is output.

Therefore, the output pressure can be continuously controlled from the negative pressure to the positive pressure by adjusting the amount of electricity supplied to the electromagnetic portion.

[Embodiment] FIG. 1 shows an embodiment of the present invention. This proportional electromagnetic pressure control valve comprises an electromagnetic section 1 and a valve section 2.

The electromagnetic unit 1 has a proportional solenoid (not shown), which allows the entire stroke of the movable core to be
It is configured so as to obtain a constant electromagnetic driving force proportional to the amount of energization.

On the other hand, the valve body 4 in the valve portion 2 has a through hole 5 in the axial direction.
Further, it has an output port 6, a positive pressure port 7, and a negative pressure port 8 which communicate with each other, the output port 6 is for a desired load, the positive pressure port 7 is for a positive pressure source such as a compressor, an air receiver, and a negative pressure source. The pressure port 8 is connected to a negative pressure source such as a vacuum port or an ejector, and the output port 6 is connected to a spool 12 slidably inserted in a sleeve 11 fitted in the through hole 5 and the output port 6 is a positive pressure port. An intermediate land 12a is formed so as to be switched between 7 and the negative pressure port 8 to communicate with each other.

One end of the through hole 5 is closed by a spring seat 13 screwed to the valve body 4, and a feedback chamber 14 is formed between the through hole 5 and the spool 12.
Is connected to the output port 6 by a feedback passage 15 opened in the chamber, and in the chamber 14, a spring 16 for exerting an acting force against the driving force of the electromagnetic section 1 on the spool 12 is provided.
Has been reduced.

The other end of the spool 12 abuts on a valve rod 1a that is driven integrally with the movable iron core of the electromagnetic unit 1, and the driving force of the energization of the electromagnetic unit 1 is the urging force of the spring 16 and the fluid pressure of the feedback chamber 14. When it becomes larger than the sum of the acting forces by the spool 12
Moves, and the opening degrees of the positive pressure port 7 or the negative pressure port 8 and the output port 6 are adjusted so that an output pressure proportional to the amount of electricity supplied to the electromagnetic unit 1 can be obtained.

Further, even when the feedback pressure in the feedback chamber 14 is a negative pressure, the spring 16 is provided with an urging force that causes the spool 12 to slide in the electromagnetic portion 1 direction against it. That is, the urging force of the spring 16 is set so that the valve member can be moved to a position where the output port 6 and the negative pressure port 8 communicate with each other in the fully opened state against the maximum negative feedback action force in the feedback chamber 14. There is.

Next, the operation of the above embodiment will be described.

FIG. 1 shows a state in which the electromagnetic unit 1 is not energized and the maximum negative feedback force is acting on the feedback chamber. The spool 12 is connected to the negative pressure port 8 and the output port 6 by the urging force of the spring 16. However, they communicate at the maximum opening position.

When the proportional solenoid is excited by energization, an electromagnetic driving force proportional to the energization amount is generated in the electromagnetic section 1. When this driving force is larger than the biasing force of the spring 16 and the fluid pressure acting force of the feedback chamber 14, the spool 12 moves Slide to the position where the force of is balanced.

Therefore, the output pressure can be continuously controlled from the negative pressure to the positive pressure by adjusting the amount of electricity supplied to the electromagnetic unit 1.

FIG. 2 is a current-pressure characteristic diagram showing the results of an experiment using the proportional electromagnetic pressure control valve having the configuration shown in FIG.
As a result, it is possible to perform continuous proportional control from negative pressure to positive pressure.

[Effects of the Invention] In the present invention, negative pressure can be controlled in an analog manner by an electric signal, and the output range can be continuously controlled from negative pressure to positive pressure by one proportional electromagnetic pressure control valve. Therefore, the application area of the proportional electromagnetic pressure control valve can be expanded.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an embodiment of the present invention, and FIG.
It is an electric current-pressure characteristic diagram showing the result of having experimented using the proportional electromagnetic pressure control valve of the figure. 1 ... Electromagnetic part, 2 ... Valve part, 4 ... Valve body, 6 ... Output port, 7 ... Positive pressure port, 8 ... Negative pressure port, 12 ...
Spool, 14 …… Feedback chamber, 16 …… Spring.

Claims (1)

[Scope of utility model registration request] 1. An electromagnetic section having a proportional solenoid, and a valve section provided with a spool whose opening of a flow path is controlled by driving by the proportional solenoid.
In a proportional solenoid type pressure control valve in which an electromagnetic driving force proportional to the amount of electricity in the proportional solenoid and a fluid pressure acting force fed back from the output port are made to act, the valve body has a positive pressure communicating with a positive pressure source. A pressure port, a negative pressure port communicating with a negative pressure source, and the output port communicating with a load, and the spool with the electromagnetic driving force of a proportional solenoid,
The output pressure can be switched between the positive pressure port and the negative pressure port by operating the fluid pressure force and the spring biasing force fed back to the feedback chamber in opposition to each other, and moving the spool depending on the magnitude of these forces. The spring urging force is set to a size that moves the spool to a position where the output port and the negative pressure port communicate with each other at the maximum opening when the negative maximum feedback action force acts on the feedback chamber. The proportional electromagnetic pressure control valve capable of continuously controlling the pressure from negative pressure to positive pressure, characterized in that the output port communicates with the spool from the negative pressure port to the positive pressure port.