JP2537168Y2 - Electric-fluid pressure regulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electric-fluid pressure regulator for supplying a pressure fluid to a pressure tank.

[Prior Art] An electric-fluid pressure regulator shown in FIG. 5 can be considered as a device for supplying a pressure fluid to a pressure tank.

The electric-fluid pressure regulator shown in FIG. 5 has an air operated main valve 2 having a supply port P communicating with a pressure fluid source and an output port A communicating with a pressure tank 1, an input electric signal and a fluid in the pressure tank 1. The control circuit 4 compares the magnitude of the feedback electric signal fed back from the pressure sensor 3 for converting the pressure into an electric signal, and outputs a drive current according to the magnitude of the electric signal. Pilot valve 4 that outputs fluid
It is composed of

In the electric-fluid pressure regulator, the control circuit 4 compares the magnitude of the input electric signal with the magnitude of the feedback electric signal. When the magnitude of the feedback electric signal is small, a drive current is output from the control circuit 4 to the solenoid valve 5. When the port P and A of the main valve 2 communicate with each other by the pilot fluid output from the controller to supply the pressure fluid to the pressure tank 1, and the internal pressure of the tank 1 increases, the feedback electric signal becomes larger than the input electric signal. The drive current from the circuit 4 is cut off and the communication between the ports P and A of the main valve 2 is cut off.

FIG. 6 shows an example of the control circuit 4 in the above-mentioned electro-hydraulic pressure regulator. The magnitude of the input signal amplified by the input signal amplifier 11 and the magnitude of the feedback electric signal from the pressure sensor 3 amplified by the differential amplifier 12 are shown. Are compared in the comparison circuit 13. When the input electric signal is larger than the feedback electric signal, the drive circuit 14 outputs a drive current to the solenoid of the pilot solenoid valve 5. Reference numerals 15 and 16 in the figure denote zero adjustment. And the power supply for the sensor.

The above-mentioned electric-fluid pressure regulator has an advantage that the structure is simple and inexpensive because the main valve 2 can be constituted by an on-off valve, but the fluctuation in the tank internal pressure is large as shown in FIG. 7A. There's a problem.

When the internal pressure of the pressure tank 1 reaches a set pressure determined by the input electric signal, the output of the control circuit 4 is cut off and the communication between the ports P and A of the main valve 2 is cut off. This is because the internal pressure of the pressure tank 1 is increased by the pressurized fluid flowing until the communication between the ports P and A is completely interrupted because the effective sectional area of the path is large. This pressure fluctuation is largest at the first, but when the pressure rises, the main valve 2
Is fully opened and a large amount of pressure fluid is supplied to the pressure tank 1, so that the time until the main valve 2 is completely closed becomes longer, and the subsequent pressure fluctuation is smaller than this. This is because the internal pressure of the tank rises to the set pressure during the opening operation of the valve 2, so that the closing operation is performed before the main valve is fully opened, thereby shortening the closing time.

As described above, the electro-fluid pressure regulator considered from the related art has a problem that the internal pressure of the pressure tank 1 fluctuates greatly, which is not preferable for a fluid device using this pressure fluid.

[Problems to be Solved by the Invention] The present invention is to solve the problem of reducing the internal pressure fluctuation of the pressure tank in an electro-hydraulic pressure regulator for supplying a pressure fluid to the pressure tank. Things.

Means for Solving the Problems To solve the above problems, the present invention provides a two-port main valve having a supply port communicating with a pressure fluid source and an output port communicating with a pressure tank, and an input electric signal. A control circuit that compares the magnitude of a feedback electric signal fed back from a pressure sensor that converts the fluid pressure of the pressure tank into an electric signal, and outputs a driving current according to the magnitude of the electric signal; In an electro-hydraulic pressure regulator provided with a pilot solenoid valve that outputs a fluid and connects a supply port of a main valve and an output port, a supply amount of a pilot fluid supplied to the main valve is supplied to a flow path of the pilot fluid. It is characterized in that a speed controller for restricting and opening the flow path of the main valve at a low speed is provided.

[Operation] When the input electric signal is input to the control circuit, the control circuit compares the magnitude of the input electric signal with the feedback electric signal obtained by converting the fluid pressure in the tank from the pressure sensor, and inputs the feedback electric signal. If less than the electrical signal, the control circuit outputs a drive current to the pilot solenoid valve, thereby supplying the main valve with pilot fluid from the solenoid valve.

Since the pilot fluid is meter-in controlled by a speed controller, the main valve opens at a low speed to supply pressure fluid to the pressure tank, and when the feedback electric signal becomes larger than the input electric signal due to an increase in the pressure of the pressure tank, The drive current from the control circuit is cut off and the main valve closes.

In this case, since the main valve opens at a low speed by the meter-in control of the pilot fluid by the speed controller, the fluid pressure in the pressure tank rises to a predetermined set pressure and the main valve is closed before the main valve is fully opened. In addition, the closing time of the main valve is shortened, and the fluctuation of the internal pressure of the pressure tank can be reduced.

[Embodiment] FIG. 1 is a schematic structural view of an embodiment of the present invention. This electro-hydraulic pressure regulator has an air pressure having a supply port P communicating with a pressure fluid source and an output port A communicating with a pressure tank 21. Actuating main valve 22, input electric signal and pressure tank
The control circuit 24 compares the magnitude of the feedback electric signal fed back from the pressure sensor 23 which converts the fluid pressure of 21 into an electric signal, and outputs a drive current according to the magnitude of these electric signals. A pilot solenoid valve 25 that outputs pilot air to the main valve 22, and a meter-in control speed controller 27 in a pilot flow path 26 that communicates the solenoid valve 25 with the main valve 22, that is, a pilot fluid to the main valve 22. A speed controller 27 for limiting the supply amount is provided.

In the above embodiment, since the pilot air supplied to the main valve 22 is meter-in controlled by the speed controller 27, the rise of the fluid pressure in the pilot chamber of the main valve is delayed, and the main valve 22 opens at a low speed. In addition, since the opening degree of the main valve 22 when the internal pressure of the pressure tank 21 rises to the set pressure is small, the closing time of the main valve due to discharge of pilot air can be shortened. twenty one
Of the internal pressure can be reduced.

The above-mentioned electric-fluid pressure regulator has an advantage that the internal pressure fluctuation of the pressure tank 21 can be reduced, but when the pressure tank 21 rises, a large amount of pressure fluid is supplied to the tank, and the opening of the main valve 22 increases. Therefore, the pressure fluctuation at the time of rising cannot be reduced.

FIG. 2 is a block diagram of a control circuit for reducing the pressure fluctuation at the time of rising of the pressure tank 21. The control circuit 24 lowers the set pressure at the time of rising of the tank and closes the main valve 22 early. Then, the internal pressure of the tank at the time of rising is made lower than the set pressure, and thereafter, it is raised to the normal set pressure.

The first comparison circuit 18 in the control circuit 24 compares the input signal amplifier 11 with the output of the differential amplifier 12 that amplifies the feedback electric signal from the pressure sensor 23. When the output of the input signal amplifier 11 is large, The electric signal is outputted to the input signal amplifier 11 so as to reduce the electric signal. Accordingly, the output of the input signal amplifier 11 inputted to the second comparison circuit 19 is small at the time of rising, and gradually increases as the internal pressure of the tank 21 increases. As the pressure increases, the internal pressure rises to the normal set pressure. Since the other configuration in FIG. 2 is the same as that in FIG. 6, the same reference numerals are given in the figure and the detailed description is omitted.

FIG. 3 shows a configuration diagram of the above-mentioned control circuit, which is substantially the same as FIG. 2, so that the same reference numerals are given and the detailed description is omitted.

According to the control circuit 24 shown in FIGS. 2 and 3, in combination with the speed controller 27, it is possible to reduce the abnormal rise of the internal pressure and the subsequent pressure fluctuation when the pressure tank 21 rises (see FIG. 7B). .

FIG. 4 is a longitudinal sectional front view of a main part of the embodiment in which the main valve 22, the pilot solenoid valve 25, and the speed controller 27 are integrated. The valve body 31 of the main valve 22 has a supply port P and an output port A, The pilot chamber main body 32 attached to the valve main body 31
Is provided with an inlet port 33 and an outlet port 34 of the pilot solenoid valve 25, respectively. A valve rod 38 of a valve body 37 that opens and closes a valve seat 36 formed in a flow path connecting the ports P and A is provided between the main bodies 31 and 32. A piston 40 is fixed to a tip that air-tightly penetrates the partition, and the pilot chamber main body 32 is divided into a pilot chamber 41 and a breathing chamber 42 by the piston 40, and is returned to the breathing chamber 42 by a spring.
42 have been reduced.

A speed controller 27 and a pilot solenoid valve 25 are sequentially mounted on the pilot chamber main body 32, and a flow passage 45 communicating with an input port of the pilot solenoid valve 25 is opened at an inlet port 33, and a flow passage communicating with an output port is provided. Road 46 is a speed controller
27 and the pilot flow path 26 open the pilot chamber 41, and the flow path 47 communicating with the discharge port opens to the outlet port. The speed controller 27 has a variable throttle 49 and a check valve
50, the screw shaft 49a of the variable throttle 49 is screwed to the speed controller main body, and by rotating a knob protruding out of the main body to advance and retreat with respect to the main body, the flow path
The throttle opening of the pilot flow path 46 and the pilot flow path 26 can be adjusted.

On the other hand, the check valve 50 is provided with a valve seat 5 provided at a location where the flow path 46 communicates with the variable throttle 49 and the bypass 26a of the pilot flow path 26.
2 and a valve member 53 for closing the valve seat 52 from the flow channel 46 side, and when pilot air pressure is acting on the flow channel 46, the valve member 53 closes the valve seat 52 to close the pilot chamber 41. The flow of the fluid to the outside is prevented, and the pilot air in the flow path 46 is connected to the output port and the discharge port of the pilot solenoid valve 25 and the flow path 47 communicating therewith.
When the air is discharged to the outside through the valve member 53, the valve member 53 opens the valve seat 52, and discharges the pilot air in the pilot chamber 41 to the outside from the outlet port 34 through the flow path 51.

When the solenoid is excited by a drive current from a control circuit 24 (not shown), the pilot solenoid valve 25 communicates with the input port and the output port to close the discharge port, and when the excitation of the solenoid is released. A well-known three-port solenoid valve in which the output port communicates with the discharge port to close the supply port.
Variable throttle 49 of speed controller 27 in pilot room 41
When the pilot fluid is supplied through, the piston 40 moves upward in the figure, the valve element 37 opens the valve seat 36, and when the pilot air in the pilot chamber 41 is discharged through the check valve 50, The valve body 37 returns to the illustrated state by the urging force of the return spring 43, and closes the valve seat 36.

[Effect of the Invention] The electric-fluid pressure regulator of the present invention compares the magnitude of an input electric signal with the magnitude of a feedback electric signal fed back from a pressure sensor that converts the fluid pressure in the pressure tank into an electric signal, and compares the magnitude of the feedback electric signal. Is smaller than the input signal, the control circuit drives the pilot solenoid valve, and the pilot fluid output from the solenoid valve connects the supply port and the output port of the main valve. Can be increased to a pressure corresponding to the pressure.

Also, by providing a speed controller for restricting the supply amount of the pilot fluid to be supplied to the main valve and opening the flow path of the main valve at a low speed in the pilot flow path that connects the pilot solenoid valve and the main valve. In addition, while the opening of the main valve is small, the internal pressure of the tank can be increased to shorten the closing time of the main valve, thereby reducing the fluctuation of the internal pressure of the tank.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of a control circuit of the same, FIG. 3 is a block diagram of a control circuit of FIG.
FIG. 4 is a longitudinal sectional front view of an essential part of an embodiment in which a main valve, a pilot solenoid valve and a speed controller are integrated, FIG. 5 is a configuration diagram of an electric-fluid pressure regulator conceivable from the prior art, and FIG. FIG. 7A and FIG. 7B are block diagrams of a control circuit in the electric-fluid pressure regulator shown in FIG. 21 ... Pressure tank, 22 ... Main valve, 23 ... Pressure sensor, 24
Control circuit, 25 Pilot solenoid valve, 26 Pilot flow path, 27 Speed controller, P Supply port, A Output port

Claims (1)

(57) [Scope of request for utility model registration] 1. A two-port main valve having a supply port communicating with a source of pressure fluid and an output port communicating with a pressure tank, and feedback from an input electric signal and a pressure sensor for converting the fluid pressure of the pressure tank into an electric signal. A control circuit that compares the magnitude of the feedback electric signal and outputs a drive current according to the magnitude of the electric signal, and outputs a pilot fluid by the drive current to communicate between the supply port and the output port of the main valve. An electro-fluid pressure regulator comprising a pilot solenoid valve and a speed controller for opening the main valve at a low speed by limiting a supply amount of the pilot fluid supplied to the main valve to the flow path of the pilot fluid. An electric-fluid pressure regulator provided.