JPH05297958A - Remote control type automatic control valve - Google Patents

Abstract

PURPOSE:To reduce the wiring cost and also to prevent the mixture of noises by providing a converting part into an automatic control valve to convert the signal sent from a sensor and connecting the converting part to a controller via an electric signal line. CONSTITUTION:A CPU 65 of an automatic control valve compares an optional target level of the pressure to be set that is inputted to a set input circuit 66 with the pressure signal which is inputted from a pressure sensor 54 via a converting part 55. Then the CPU 65 performs the differential/integral operations based on the relation stored previously and sends a motor drive signal to the part 55. Thus the motor of a driving part 52 is driven and the pressure is set with the back and force movements of a control screw of a control part 51. Under such conditions, an electric signal line 57 reaching the part 55 from the sensor 54 can be shortened since the part 55 is connected to a controller 56 via an electric signal line 58. Thus it is possible to reduce the wiring cost and to prevent the mixture of noises.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve which is attached to a fluid pipe to control the pressure, temperature, flow rate, etc. of a fluid, and particularly to detect a process amount, compare it with a target value, and make a judgment based on a deviation.
The present invention relates to an automatic control valve that processes a command or the like as a signal and controls a drive unit such as an electric motor that operates a valve body.

[0002]

2. Description of the Related Art A conventional automatic control valve is disclosed, for example, in Japanese Patent Laid-Open No. 63-63.
It is disclosed in Japanese Patent Publication No. -20603. This is configured to adjust the set pressure of the valve by rotating the adjusting screw to move it in the axial direction and changing the urging state of the pressure setting spring by the movement. The motor is used to move the adjusting screw in the axial direction based on the relationship. When remotely operating this automatic setting pressure reducing valve, the configuration is as shown in FIG. That is, the automatic setting pressure reducing valve is composed of the pressure reducing valve 70, the adjusting unit 71, and the driving unit 72. The adjusting unit 71 corresponds to the pressure setting spring, the adjusting screw, and the like, and the driving unit 72 also moves the adjusting screw. And a control unit that controls the drive of the electric motor. Further, 73 is a steam using device such as a heat exchanger connected to the secondary side of the pressure reducing valve 70, 74 is a pressure sensor for detecting the pressure of the fluid supplied to the steam using device 73, and 75 is input from the pressure sensor 74. The pressure signal is compared with the set pressure target value input from 76, and the drive unit 72 is operated to perform a proportional operation,
Alternatively, it is a controller for performing a differential / integral operation, and is arranged remote from the automatic setting pressure reducing valve and the pressure sensor 74. 77,
Reference numeral 78 is an electric signal line.

[0003]

SUMMARY OF THE INVENTION In the above conventional one,
Although the automatic setting pressure reducing valve and the pressure sensor are placed close to each other,
Since the controller is arranged remotely from the automatic setting pressure reducing valve and the pressure sensor, the wiring cost of the electric signal line connecting the controller with the automatic setting pressure reducing valve and the pressure sensor is high, and noise easily mixes in. was there. Therefore, a technical problem of the present invention is to obtain a remote control type automatic control valve which reduces wiring cost and is less likely to mix noise.

[0004]

The technical means of the present invention taken to solve the above-mentioned technical problem is to arrange a sensor for detecting a process amount near an automatic control valve, and a signal from the sensor is In a remote-controlled automatic control valve in which a controller that controls the drive part of the automatic control valve based on the deviation that is input and compared with the set target value is located remotely from the automatic control valve and sensor, The signal conversion unit is provided, and the conversion unit and the controller are connected by an electric signal line.

[0005]

The operation of the above technical means is as follows.
The converter of the signal from the sensor is installed inside the automatic control valve.
Since the conversion unit and the controller are connected by the electric signal line, the electric signal line from the sensor to the conversion unit can be shortened, the wiring cost can be reduced, and noise is less likely to be mixed.

[0006]

EXAMPLE An example showing a concrete example of the above technical means will be described (see FIGS. 1 and 2). FIG. 2 shows an automatically set pressure reducing valve as an automatic control valve. An inlet 1 and an outlet 2 and a main valve opening 3 are formed by valve casing, and the main valve opening 3 is opened and closed by a main valve body 5 biased in a valve closing direction by a main valve spring 4. The piston 9 is slidably arranged in the cylinder 10, and the lower piston rod of the piston 9 contacts the upper protrusion of the main valve body 5. The fluid pressure on the outlet 2 side acts on the lower surface of the piston 9, and the fluid pressure on the inlet 1 side is introduced to the upper surface through the primary pressure passages 11 and 12 under the control of the pilot valve 13. The pilot valve 13 is biased by a spring in the valve closing direction, hits the lower surface of the diaphragm 14 via the valve rod, and receives the operating force in the valve opening direction due to its displacement.

The lower end of the pressure setting spring 16 abuts on the upper surface of the diaphragm 14 via the diaphragm retainer 15 and an elastic force acts. The lower end of the adjusting screw 19 contacts the upper end of the pressure setting spring 16 via the spring receiving member 17 and the ball 18, and the amount of compression of the pressure setting spring 16 is adjusted by moving the adjusting screw 19 forward and backward to adjust the diaphragm. The elastic force acting on 14 can be adjusted. Adjustment screw 19
Is screwed to a bearing portion 21 fixed to a spring housing case 20 forming a part of the valve casing. Diaphragm 1
The lower surface of 4 faces the diaphragm chamber 25 through the secondary side detection passage 24 communicating with the outlet 2.

When the adjusting screw 19 rotates left and right, the elastic force of pushing down the diaphragm 14 of the pressure setting spring 16 changes. Therefore, when the diaphragm 14 is displaced downward, the pilot valve 13 is pushed down and opened, and the fluid at the inlet 1 is introduced above the piston 9 through the passages 11 and 12.
The main valve body 5 is pushed down by the piston 9, the main valve opening 3 is opened, and the fluid at the inlet 1 flows to the outlet 2. When the pressure on the secondary side rises, the diaphragm chamber 2 passes through the secondary side detection passage 24.
The pressure of 5 also rises, and the diaphragm 14 is displaced upward. As a result, the pilot valve 13 is pushed up and closed, the fluid supplied to the upper part of the piston 9 is reduced, the main valve body 5 is pushed up by the main valve spring 4, and the main valve port 3 is closed. By repeating the above, the pressure on the secondary side is maintained at a desired value.

When changing the set pressure, the adjusting screw 19 is rotated to change the urging force of the pressure setting spring 16 to the diaphragm 14. The mechanism for rotating the adjusting screw 19 will be described below. A fitting hole 28 for fitting the output shaft 27 of the electric motor 26 is formed in the upper part of the adjusting screw 19, and two notches 29 are formed around the fitting hole 28. The pin 30 is passed through the output shaft 27 and fixed, and both ends of the pin 30 are cut out 29
Then, the output shaft 27 is fitted into the fitting hole 28. The electric motor 26 is composed of a speed reducer 31 having an output shaft 27 and a motor 32 connected to the input side of the speed reducer 31, and is fixed to a mounting base 33 fixed to the housing case 20 and covered with a cover 34. Be seen. With respect to the rotation of the output shaft 27 at the fixed position, the adjusting screw 19 moves in the axial direction while rotating through the pin 30. A motor drive circuit 35 for supplying a drive signal to the motor 32 is arranged in the cover 34. A potentiometer 36 for detecting the axial position of the adjusting screw 19 on the mounting base 32.
Attach.

FIG. 1 shows a block diagram for remotely operating the automatic setting pressure reducing valve. The automatic setting pressure reducing valve 69 is the pressure reducing valve 50,
The adjusting unit 51, the driving unit 52, and the converting unit 55 correspond to the pressure setting spring 16 and the adjusting screw 19 described above, and the driving unit 52 also includes the electric motor 26, the motor driving circuit 35, and the potentiometer. -The meter 36 etc. correspond. Again 53
Is a steam using device such as a heat exchanger connected to the secondary side of the pressure reducing valve 50, 54 is a pressure sensor for detecting the pressure of the fluid supplied to the steam using device 53, and 55 is a signal input from the pressure sensor 54. The converter 56 is a set pressure target value and the converter 5
5 is a controller that compares the signal input from 5 to perform differential / integral calculation and sends a motor drive signal to the conversion unit 55, and is arranged remotely from the automatic setting pressure reducing valve and the pressure sensor 54. 57 and 58 are electric signal lines. The conversion unit 55 includes a power source 59, a sensor input circuit 60, a CPU 61, a communication circuit 62.
And the sensor input circuit 60 has an amplifier A / D
It has a converter and converts the pressure signal from the pressure sensor 54 into a digital signal. The controller 56 includes a power source 63 and a communication circuit 6
4, a CPU 65, a setting input circuit 66, and a display circuit 67. The CPU 65 stores the relationship between the position of the adjusting screw 19 and the set pressure in advance.

When an arbitrary set pressure target value to be set is input from 68 to the setting input circuit 66, the CPU 65 compares it with the pressure signal from the pressure sensor 54 input via the conversion unit 55 and stores it in advance in a stored relationship. The differential / integral calculation is performed based on the above, and the motor drive signal is transmitted to the conversion unit 55. As a result, the electric motor 26 of the drive unit 52 is driven, and the adjustment unit 51
The adjusting screw 19 is moved back and forth to adjust the elastic force of the pressure setting spring 16. When the potentiometer 36 of the drive unit 52 detects that the adjusting screw 19 is displaced to the position where it should be stopped, the drive of the electric motor 26 is stopped.

[0012]

As described above, according to the present invention, the wiring cost can be greatly reduced, and a highly accurate remote control type automatic control valve can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of a remote-controlled automatic control valve according to an embodiment of the present invention.

FIG. 2 is a sectional view of an automatic setting pressure reducing valve used in an embodiment of the present invention.

FIG. 3 is a block diagram of a conventional remote-controlled automatic control valve.

[Explanation of symbols]

 50 Pressure reducing valve 51 Adjustment unit 52 Drive unit 54 Pressure sensor 55 Conversion unit 56 Controller 57, 58 Electric signal line 66 Setting input circuit

Claims (1)

[Claims] 1. A controller for arranging a sensor for detecting a process amount in the vicinity of an automatic control valve, which receives a signal from the sensor, compares it with a set target value, and controls a drive section of the automatic control valve based on a deviation. A remote-controlled automatic control valve in which a converter for signals from the sensor is provided inside the automatic control valve and the sensor arranged remotely, and the converter and the controller are connected by an electric signal line.