CN204269293U - Low static pressure differential pressure producer - Google Patents

Abstract

The utility model discloses a low static pressure differential pressure generator, which belongs to the field of automatic meter calibration instruments. A digital display, a second digital display, an alarm and a keyboard, the detection unit includes an A/D converter, a pressure transmitter and a differential pressure transmitter, and the drive unit includes a D/A converter and an empty Press machine, the gas path unit includes an air storage tank, a first solenoid valve, an air filter, an electric regulating valve, a third solenoid valve, a second solenoid valve and an output interface. The utility model uses The closed-loop control technology ensures the accuracy of static pressure and differential pressure signals, and realizes automatic calculation of output differential pressure points, automatic forward and reverse stroke output, and automatic overpressure alarm and protection. The upper limit of the static pressure of the utility model is 1MPa.

Description

Low Static Pressure Differential Pressure Generator

technical field

The utility model relates to a low static pressure differential pressure generator, which belongs to the field of automatic meter calibration instruments.

Background technique

Differential pressure signals are widely used in the inspection and identification of equipment, sensors and instruments. Because these equipment need not only differential pressure signals but also static pressure signals during calibration, and differential pressure signals are generally small, at most only a few Ten kilopascals, most of the middle and high static pressure calibration instruments are used now. Manually adjust the static pressure and differential pressure signal. The medium is transformer oil, which is prone to oil leakage and human reading errors.

Utility model content

The technical problem to be solved by the utility model is to provide a low static pressure differential pressure generator with compressed air as the pressure medium, automatic adjustment of static pressure and differential pressure, automatic positioning of calibration points, and an upper limit of static pressure of 1 MPa.

In order to achieve the above object, the utility model is realized through the following technical solutions: the low static pressure differential pressure generator is characterized in that it includes a single-chip microcomputer unit, a detection unit, a drive unit and an air circuit unit, and the described single-chip microcomputer unit includes a single-chip microcomputer, And the first digital display, the second digital display, the alarm and the keyboard electrically connected with the single-chip microcomputer respectively, the detection unit includes an A/D converter electrically connected with the single-chip microcomputer, and the A pressure transmitter and a differential pressure transmitter electrically connected to the A/D converter, the drive unit includes a D/A converter and an air compressor electrically connected to the single-chip microcomputer respectively, and the air circuit The unit includes an air storage tank connected to the air compressor pipeline, a first solenoid valve installed on the upper part of the air storage tank, an air filter connected to the air storage tank pipeline, and the The electric regulating valve connected to the air filter pipeline, the third solenoid valve connected to the air filter pipeline, the second solenoid valve connected to the electric regulating valve pipeline, and the second The low-pressure output interface connected to the pipeline of the solenoid valve, the high-pressure output interface connected to the pipeline of the third solenoid valve, the positive pressure chambers of the pressure transmitter and the differential pressure transmitter are respectively connected to the air filter On the pipeline between the transmitter and the third solenoid valve, the negative pressure chamber pipeline of the differential pressure transmitter is connected to the pipeline between the electric regulating valve and the second solenoid valve, and the electric regulating valve and the D /A converter is electrically connected.

Further, the first digital display is a dual-screen display, the upper screen displays the static pressure value in the pipeline, and the lower screen displays the differential pressure value.

Further, the second digital display is a single-screen display for displaying the opening degree of the electric regulating valve.

Furthermore, the electric control valve mentioned above is a ZRSX series control valve produced by Shanghai Shengchang Automatic Control Valve Company.

The beneficial effect of the utility model is that since the closed-loop control technology is adopted for the static pressure and the differential pressure, the accuracy of the static pressure and the differential pressure signal is ensured, and the automatic calculation of the output differential pressure point, the automatic positive and negative stroke output and the automatic overshoot are realized. Pressure alarm and protection, the static pressure upper limit of the utility model is 1MPa.

Description of drawings

Fig. 1 is a structural system diagram of the utility model.

The meanings of the marks in the attached drawings are as follows:

1. Single-chip microcomputer unit 2. Detection unit 3. Drive unit 4. Air circuit unit 5. Single-chip microcomputer 6. First digital display 7. Second digital display 8. Alarm 9. Keyboard 10. Pressure transmitter 11. Differential pressure changer Transmitter 12. A/D Converter 13. D/A Converter 14. Air Compressor 15. Air Storage Tank 16. First Solenoid Valve 17. Air Filter 18. Electric Regulating Valve 19. Second Solenoid Valve 20. The third electromagnetic valve 21, high pressure output interface 22, low pressure output interface.

Detailed ways

The utility model will be further described in detail below in conjunction with the drawings and specific embodiments.

With reference to Fig. 1, the utility model low static pressure differential pressure generator comprises single-chip microcomputer unit 1, detection unit 2, drive unit 3 and gas path unit 4, and described single-chip microcomputer unit 1 comprises single-chip microcomputer 5 and described single-chip microcomputer 5 A first digital display 6, a second digital display 7, an alarm 8 and a keyboard 9 electrically connected respectively, and the detection unit 2 includes an A/D converter 12 electrically connected with the single-chip microcomputer 5, and respectively connected with the The pressure transmitter 10 and the differential pressure transmitter 11 electrically connected to the A/D converter 12 described above, the drive unit 3 includes the D/A converter 13 and the air pressure transmitter electrically connected to the single chip microcomputer 5 respectively. machine 14, the air circuit unit 4 includes an air storage tank 15 connected to the air compressor 14, a first electromagnetic valve 16 installed on the upper part of the air storage tank 15, and the air storage tank 15 The air filter 17 connected to the air tank 15 pipeline, the electric control valve 18 connected to the air filter 17 pipeline, the third solenoid valve 20 connected to the air filter 17 pipeline, and the The second electromagnetic valve 19 connected to the electric control valve 18 pipeline, the low-pressure output interface 22 connected to the pipeline of the second electromagnetic valve 19, and the high-pressure output interface 21 connected to the pipeline of the third electromagnetic valve 20 , the positive pressure chambers of the pressure transmitter 10 and the differential pressure transmitter 11 are respectively connected to the pipeline between the air filter 17 and the third electromagnetic valve 20, and the differential pressure transmitter 11 The pipeline of the negative pressure chamber is connected to the pipeline between the electric regulating valve 18 and the second electromagnetic valve 19, and the electric regulating valve 18 is electrically connected with the D/A converter 13.

Further, the first digital display 6 is a dual-screen display, the upper screen displays the static pressure value in the pipeline, and the lower screen displays the differential pressure value.

Further, the second digital display 7 is a single-screen display for displaying the opening degree of the electric regulating valve 18 .

Further, the electric regulating valve 18 is a ZRSX series regulating valve produced by Shanghai Shengchang Automatic Control Valve Company.

The working process of the utility model:

First, connect the instrument or equipment that needs differential pressure signal through the high-pressure output interface 21 and the low-voltage output interface 22, and then set the static pressure, differential pressure value range, output differential pressure points, positive and negative travel through the keyboard 9 of the single-chip unit 1 , alarm value, when working, the utility model is composed of a pressure transmitter 10, an A/D converter 12, a single-chip microcomputer unit 1, an air compressor 14 and a first solenoid valve 16 to form a pressure closed-loop control system, and the pressure in the pipe passes through the first electromagnetic valve. The pulse switch control of the valve 16, the static pressure in the pipe is measured by the pressure transmitter 10, and the pressure value is displayed by the upper screen of the first digital display 6; , D/A converter 13 and electric regulating valve 18 constitute a differential pressure closed-loop control system, and the differential pressure is regulated by controlling the opening of the electric regulating valve 18 . If the pressure in the pipeline exceeds the set safety pressure, the alarm 8 sends an audible and visual alarm signal, and simultaneously starts the interlock protection, opens the first electromagnetic valve 16, and starts the pressure relief protection to ensure personal and equipment safety.

The utility model can set multiple differential pressure points at one time when setting the pressure, and output the differential pressure sequentially according to the set differential pressure points during operation, and can automatically work in positive and negative strokes, and can also be controlled by the utility model according to the set differential pressure range. Automatically calculate and set the differential pressure output point.

Claims (6)

1. a low static pressure differential pressure producer, is characterized in that: comprise single machine unit (1), detecting unit (2), driver element (3) and gas circuit unit (4).

2. low static pressure differential pressure producer according to claim 1, it is characterized in that: described single machine unit (1), the first numerical monitor (6), the second numerical monitor (7), alarm (8) and the keyboard (9) that comprise single-chip microcomputer (5) and be electrically connected respectively with described single-chip microcomputer (5).

3. low static pressure differential pressure producer according to claim 1, is characterized in that: described detecting unit (2) comprises the A/D converter (12) be electrically connected with described single-chip microcomputer (5) and the pressure unit (10) be electrically connected with described A/D converter (12) respectively and differential pressure transmitter (11).

4. low static pressure differential pressure producer according to claim 1, is characterized in that: described driver element (3) comprises the D/A converter (13) and air compressor machine (14) that are electrically connected with described single-chip microcomputer (5) respectively.

5. low static pressure differential pressure producer according to claim 1, it is characterized in that: described gas circuit unit (4) comprises the gas-holder (15) be connected with described air compressor machine (14) pipeline, be arranged on first solenoid valve (16) on described gas-holder (15) top, the air strainer (17) be connected with described gas-holder (15) pipeline, the electric control valve (18) be connected with described air strainer (17) pipeline, the 3rd solenoid valve (20) be connected with described air strainer (17) pipeline, the second solenoid valve (19) be connected with described electric control valve (18) pipeline, the low pressure output interface (22) be connected with described the second solenoid valve (19) pipeline, the High voltage output interface (21) be connected with the 3rd described solenoid valve (20) pipeline.

6. according to claim 1 or claim 3 or claim 4 or low static pressure differential pressure producer according to claim 5, it is characterized in that: described pressure unit (10) and the plemum of differential pressure transmitter (11) respectively pipeline are connected on the pipeline between air strainer (17) and the 3rd solenoid valve (20), negative pressure chamber's pipeline of described differential pressure transmitter (11) is connected on the pipeline between electric control valve (18) and the second solenoid valve (19), and described electric control valve (18) is electrically connected with D/A converter (13).