JPH05233071A - Electropneumatic regulator for vacuum - Google Patents

Abstract

PURPOSE:To improve control accuracy by decreasing the flow rate of sucking, eliminating the waste of air and increasing the supplying flow rate of second- order side negative pressure at the electropneumatic regulator for vacuum. CONSTITUTION:This electropneumatic regulator for vacuum opens/closes an air suck valve element 1 and an air supply valve element 2 through pilot negative pressure and controls second-order side negative pressure. Then, this regulator is provided with a pilot part 3, main valve part 4, pressure sensor 18, two- way valve 9 for sucking air and two-way valve 12 for supplying air. Time for electrifying the two-way valves 9 and 12 for sucking and supplying air is adjusted corresponding to the differential pressure of the second-order side negative pressure detected by this pressure sensor 18 and set negative pressure shown by input signals from the outside, and the second-order side negative pressure is controlled to the set negative pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum electropneumatic regulator, and more particularly to a technique effectively applied to control a secondary side negative pressure.

[0002]

2. Description of the Related Art As a vacuum electropneumatic regulator of this type, for example, there is a nozzle flapper type vacuum electropneumatic regulator.

That is, this nozzle flapper type electro-pneumatic regulator for vacuum is provided with a T-shaped negative pressure passage, and an orifice, a negative pressure port and a nozzle are formed at the ends of this negative pressure passage, respectively, and opposed to this nozzle. The flapper is displaced by a solenoid or a piezoelectric element, and the secondary side negative pressure in the negative pressure port is controlled according to the displacement of the flapper.

[0004]

However, in the structure of the nozzle flapper type vacuum electro-pneumatic regulator described above, the secondary side negative pressure in the negative pressure port depends on the leak flow rate of the atmosphere from the nozzle corresponding to the displacement of the flapper. Since the structure controls the pressure, there is a problem that the intake flow rate increases and air is wasted.

An object of the present invention is to provide a vacuum electropneumatic regulator which can reduce the intake flow rate and eliminate the waste of air.

Another object of the present invention is to provide a vacuum electropneumatic regulator capable of increasing the supply flow rate of the secondary side negative pressure.

Another object of the present invention is to provide a vacuum electropneumatic regulator which can improve control accuracy.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0009]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, the vacuum electropneumatic regulator of the present invention has a structure for controlling the secondary side negative pressure by opening and closing the intake valve body and the intake valve body via the pilot negative pressure.

In this case, a pilot portion having a pilot chamber formed of a diaphragm, a main valve portion for opening and closing the intake valve body and the air supply valve body with the movement of the diaphragm, and a secondary side of the main valve portion. A pressure sensor that detects negative pressure,
A two-way valve for intake that sucks air in the pilot chamber,
A two-way valve for air supply for supplying the pilot chamber with atmosphere is provided, and for intake air in accordance with a differential pressure between the secondary side negative pressure detected by the pressure sensor and a set negative pressure indicated by an external input signal, The structure is such that the energization time to the air supply two-way valve is adjusted to control the secondary side negative pressure to a set negative pressure.

[0012]

According to the vacuum electropneumatic regulator having the above structure,
Since the structure for controlling the secondary side negative pressure by opening and closing the intake valve body and the air supply valve body via the pilot negative pressure, the supply flow rate of the secondary side negative pressure can be increased.

Further, since the intake valve body and the supply valve body are opened and closed via the pilot negative pressure to control the secondary side negative pressure, the intake flow rate can be reduced and the waste of air can be eliminated. ..

Further, since the pilot negative pressure is adjusted by the intake air and the air supply, the air source can be eliminated.

In this case, a pilot portion having a pilot chamber formed of a diaphragm, a main valve portion for opening and closing the intake valve body and the intake valve body with the movement of the diaphragm, and a secondary side of the main valve portion. A pressure sensor that detects negative pressure,
A two-way valve for intake that sucks air in the pilot chamber,
A two-way valve for air supply for supplying the atmosphere to the pilot chamber is provided, and intake and air supply are performed according to the differential pressure between the secondary side negative pressure detected by the pressure sensor and the set negative pressure indicated by an input signal from the outside. Since the structure is such that the energization time to the two-way valve for air is adjusted to control the secondary side negative pressure to the set negative pressure, the pressure sensor detects the secondary side negative pressure, and the detected secondary side negative pressure is detected. The control accuracy can be improved by the pressure feedback control.

[0016]

1 is a sectional view showing a vacuum electropneumatic regulator which is an embodiment of the present invention.

The vacuum electropneumatic regulator in the present embodiment is an indirect operation type in which the intake valve body 1 and the air supply valve body 2 are opened and closed via the pilot negative pressure to control the secondary side negative pressure. It comprises a part 3 and a main valve part 4.

The pilot section 3 has a pilot chamber 6 formed by a diaphragm 5. The pilot intake passage 8 between the pilot chamber 6 and the intake port 7
Is provided with a two-way valve 9 for intake air, and a two-way valve 12 for air supply is provided in a pilot air supply passage 11 between the pilot chamber 6 and the air supply port 10. The structure is such that the pilot negative pressure in the pilot chamber 6 is adjusted by air and the diaphragm 5 is moved up and down by the pressure difference from the secondary side negative pressure.

The main valve portion 4 has a movable cylinder portion 13, an air supply passage 14 is formed inside the movable cylinder portion 13, and communicates with the intake port 7. An intake valve seat 15 is formed at the upper open end of the movable cylinder portion 13, and the intake valve seat 15 is opened and closed by an intake valve body 1 which is integral with the diaphragm 5.

A cylindrical air supply valve body 2 is formed at the lower open end of the movable cylinder portion 13. The air supply valve body 2 is pressed against the air supply valve seat 20 by the urging force of the spring 16 in a normal state. The valve 5 is closed, and in the operating state, the valve 5 is moved downward in conjunction with the diaphragm 5 that resists the biasing force of the spring 16 to open the valve.

Further, a pressure sensor 18 is connected to the negative pressure port 17, and the pressure sensor 18 is connected to the negative pressure port 2 within the negative pressure port 17.
The secondary side negative pressure is detected and the detected secondary side negative pressure is sent to the controller 19.

The controller 19 compares the set negative pressure indicated by an external input signal with the secondary negative pressure detected by the pressure sensor 18 and fed back to obtain a differential pressure, and according to this differential pressure. A function of adjusting the energization time (pulse width) to the intake and supply two-way valves 9 and 12 to adjust the pilot negative pressure in the pilot chamber 6 and controlling the secondary side negative pressure to the set negative pressure Have.

Next, the operation of this embodiment will be described.

When the degree of vacuum is raised to control the secondary side negative pressure to the set negative pressure, when the input signal is input, the intake two-way valve 9 opens and the pilot negative pressure in the pilot chamber 6 decreases. Therefore, the diaphragm 5 is pushed up, the intake valve body 1 moves upward, and the intake valve seat 15 opens.

As a result, the air in the negative pressure port 17 is sucked by the vacuum pump from the intake port 7 through the intake valve seat 15 and the degree of vacuum is increased.

The secondary side negative pressure at which the degree of vacuum rises is detected by the pressure sensor 18, is compared with the set negative pressure indicated by the input signal by the controller 19, and when they match, the intake two-way valve 9 is closed.

When the degree of vacuum is reduced and the secondary side negative pressure is controlled to the set negative pressure, when the input signal is input, the air supply two-way valve 12 opens and the pilot negative pressure in the pilot chamber 6 rises. For this reason, the diaphragm 5 is pushed down, so that the intake valve body 1
Moves downward and the intake valve seat 15 closes, while the intake valve body 2 moves downward and the intake valve seat 20 opens.

As a result, the atmosphere from the air supply port 10 is supplied to the negative pressure port 17 via the air supply valve seat 20 and the degree of vacuum is lowered.

The secondary side negative pressure at which the degree of vacuum decreases is detected by the pressure sensor 18, is compared with the set negative pressure indicated by the input signal by the controller 19, and when they match, the two-way valve 12 for air supply.
Is closed.

As described above, since the secondary side negative pressure can be controlled by opening / closing the intake valve body 2 and the intake valve body 1 via the pilot negative pressure, the supply flow rate of the secondary side negative pressure can be increased. it can.

Further, the intake valve body 2 is supplied through the pilot negative pressure.
Since the intake valve body 1 is opened and closed to control the secondary side negative pressure, the intake flow rate can be reduced and the waste of air can be eliminated.

Further, since the pilot negative pressure is adjusted by the intake air and the air supply, the air source can be eliminated.

Further, since the pressure sensor 18 detects the secondary side negative pressure and the feedback control structure of the detected secondary side negative pressure is adopted, the control accuracy can be improved.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

[0035]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

(1). Since the structure for controlling the secondary side negative pressure by opening and closing the intake valve body and the intake valve body via the pilot negative pressure, it is necessary to increase the supply flow rate of the secondary side negative pressure. You can

(2) Since the intake valve body and the intake valve body are opened and closed via the pilot negative pressure to control the secondary side negative pressure, the intake flow rate is reduced and the waste of air is eliminated. You can

(3) Since the pilot negative pressure is adjusted by intake and air supply, the air source can be eliminated.

(4) In the case of the above (1), a pilot portion having a pilot chamber formed of a diaphragm, and a main valve portion for opening and closing the intake valve body and the intake valve body with the movement of the diaphragm, A pressure sensor for detecting the secondary side negative pressure of the main valve portion, an intake two-way valve for sucking air in the pilot chamber, and an air supply 2 for supplying the atmosphere to the pilot chamber.
A two-way valve for intake and air supply is adjusted according to the differential pressure between the secondary side negative pressure detected by the pressure sensor and a set negative pressure indicated by an external input signal. Since the secondary negative pressure is controlled to the set negative pressure, the pressure sensor detects the secondary negative pressure and the feedback control of the detected secondary negative pressure improves the control accuracy. be able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a vacuum electropneumatic regulator that is an embodiment of the present invention.

[Explanation of symbols]

 1 Intake valve body 2 Air supply valve body 3 Pilot section 4 Main valve section 5 Diaphragm 6 Pilot chamber 7 Intake port 8 Pilot intake passage 9 Intake 2-way valve 10 Air supply port 11 Pilot air supply passage 12 Air supply 2-way valve 13 Movable Cylinder Section 14 Air Supply Path 15 Intake Valve Seat 16 Spring 17 Negative Pressure Port 18 Pressure Sensor 19 Controller 20 Air Supply Valve Seat

Claims (2)

[Claims] 1. A vacuum electropneumatic regulator characterized by opening and closing an intake valve body and an air supply valve body via a pilot negative pressure to control a secondary side negative pressure. 2. The vacuum electropneumatic regulator according to claim 1, wherein a pilot portion having a pilot chamber formed of a diaphragm, and a main valve that opens and closes an intake valve body and an air supply valve body as the diaphragm moves. Section, a pressure sensor for detecting the secondary side negative pressure of the main valve section, an intake two-way valve for sucking air in the pilot chamber, and an air supply two-way valve for supplying the atmosphere to the pilot chamber. 2 for the intake air and the supply air according to the differential pressure between the secondary side negative pressure detected by the pressure sensor and the set negative pressure indicated by an input signal from the outside.
The electropneumatic regulator for vacuum according to claim 1, wherein the energization time to the one-way valve is adjusted to control the secondary side negative pressure to a set negative pressure.