Emptying valve device in automatic control system

Abstract

The invention discloses an emptying valve device in a control system, belongs to the field of air blowers, and overcomes the defects that an old-fashioned pneumatic switch type electromagnetic valve is easy to age and unreliable. The emptying valve device in the automatic control system is installed on a branch ventilation pipeline communicated with the side face of an air blower outlet pipeline and matched with a pressure detection device on an air outlet pipeline of an air blower main machine in a control system of air blower equipment, and the automatic control effect is achieved; an emptying valve device in the automatic control system comprises a support for installing spare parts, a butterfly valve is installed on the support, and a butterfly valve control mechanism for opening the butterfly valve to release pressure according to signals of a pressure detection device is further installed. The butterfly valve is coaxially connected with the branch ventilation pipeline through a flange, and the ventilation state of the branch ventilation pipeline depends on the state of the butterfly valve. The pressure relief valve is suitable for all occasions needing pressure relief.

Description

Technical Field

[0001] The invention belongs to the field of blowers and compressors, and relates to a vent valve device in an automatic control system. Background Art

[0002] Blower equipment is widely used, and the application requirements of each specific occasion are not necessarily the same. For example, when used for sewage treatment, the outlet pressure of the blower must be greater than the water pressure corresponding to the depth of the sewage, and the outlet pipe of the chassis can be opened and work normally. For air suspension blowers, the speed of the blower must reach the floating state of the air suspension bearing to work normally.

[0003] Blower equipment such as Figure 1 As shown, it includes the blower main unit, the chassis, the outlet pipe of the chassis, and the gas pipeline connecting the air outlet of the blower main unit and the air outlet of the chassis, and even includes the vent valve device on the side of the gas pipeline of the blower main unit outlet, and the pressure detection device of the air outlet required in the automatic control system of the blower equipment, etc.

[0004] In actual application, a connected branch ventilation pipeline is set on the side of the blower outlet pipeline, and the vent valve device is clamped and installed on the branch ventilation pipeline through a flange. When the air outlet pipeline of the blower chassis is in a closed state, the gas in the blower host can be discharged through the vent valve device on the side of the gas pipeline; the open or closed state of the vent valve depends on the pressure and flow of the blower.

[0005] It can be seen that the vent valve is one of the components that must be equipped in the blower equipment. Its function can also be to relieve the pressure of the blower host before the blower host runs to the rated speed to avoid the impeller starting under pressure. When the fan is stopped or running, if the external pressure suddenly increases, the fan cannot output air volume or the output air volume is very small, the blower outlet pipe also needs to be depressurized, otherwise it will cause the fan to surge and cause serious damage to the fan bearings, impellers and other components. The vent valve can effectively protect the safe operation of the equipment.

[0006] On an automatically controlled blower device, after the blower speed reaches the set value, the blower flow, pressure, power and other parameters reach a relatively stable state; the blower control system reads the current actual flow, pressure or power parameters and compares them with the target value: (1) When the actual flow, pressure or power parameters are less than the target value, the blower gradually increases the blower speed according to the time and step length of the speed adjustment; (2) When the actual flow, pressure or power parameters are greater than the target value, the blower gradually decreases the blower speed according to the time and step length of the speed adjustment; (3) Set the dead zone range of the blower target parameter, the blower automatically adjusts the speed, and the actual value gradually approaches the target value. When the actual value enters the dead zone range, the blower stops adjusting the speed.

[0007] The problems with the prior art are: 1. The existing vent valve usually uses a pneumatic switch-type solenoid valve to control the opening and closing of the vent valve air film, which has only two states: fully open and fully closed, and the air volume for venting and decompression cannot be adjusted; 2. Flexible film seals such as air films are used in the vent valve structure, which age and fail after multiple openings and closings, and have low reliability; 3. The vent valve makes a lot of noise when working. Summary of the invention

[0008] The present invention aims to solve a series of problems in the prior art of the above-mentioned blower equipment, and for this purpose discloses a vent valve device in an automatic control system.

[0009] The vent valve device in the automatic control system described in the present invention is installed on a branch ventilation pipe connected to the side of the blower outlet pipe, and cooperates with the pressure detection device on the blower main unit outlet pipe in the control system of the blower equipment to realize automatic control of the pressure relief of the blower main unit and the normal operation of the blower equipment; the vent valve device in the automatic control system includes a bracket for installing loose parts, a butterfly valve is installed on the bracket, and a butterfly valve control mechanism is also installed to open the butterfly valve to release pressure according to the signal of the pressure detection device; the butterfly valve is coaxially connected to the branch ventilation pipe through a flange, and the ventilation state of the branch ventilation pipe depends on the state of the butterfly valve.

[0010] A preferred technical solution is that the butterfly valve control mechanism includes a motor and a linear motion mechanism driven by the motor, and also includes a connecting rod with both ends connecting the linear motion mechanism and the butterfly valve in the form of a rotating shaft; wherein the control system converts the detected pressure of the blower outlet pipe into a signal for controlling the rotation of the motor, the rotation of the motor drives the linear motion mechanism, and the linear displacement adjusts the angle of rotation of the valve plate of the butterfly valve through the connecting rod; the power-on state of the motor determines the length of the linear displacement.

[0011] A preferred technical solution is that the motor-driven linear motion mechanism is an electric push rod mechanism composed of a DC motor, a reduction mechanism, and a screw mechanism. The reduction mechanism can be adjusted to match different opening and closing speeds to cope with various actual required opening and closing angles of the butterfly valve; the electric push rod mechanism and the butterfly valve are connected by a connecting rod, and both ends of the connecting rod are connected by rotating shafts.

[0012] Another feasible technical solution is that the motor-driven linear motion mechanism is a telescopic cylinder mechanism driven by a DC motor.

[0013] Another feasible technical solution is that the motor-driven linear motion mechanism is a linear motor that drives the valve plate of the butterfly valve to rotate.

[0014] In specific implementation, a pressure detection port is set on the gas pipeline at the main unit outlet to monitor the pressure state of the outlet pipeline when the fan is running. There are two situations: The first situation: when the fan starts, the pressure of the outlet pipeline is low because the blower speed has not reached the set value. At this time, the electric push rod mechanism is controlled to extend to open the butterfly valve; when the wind pressure of the fan reaches the set value, the electric push rod mechanism is controlled to retract and close the butterfly valve; the principle is the same when the fan is stopped. When the fan speed drops and the wind pressure is lower than the pipeline pressure, the butterfly valve needs to be opened to exhaust until the fan stops completely.

[0015] The second situation: During the operation of the fan, when an abnormal increase in outlet pressure is detected, the electric push rod mechanism is controlled to extend, open the butterfly valve, and set the opening of the butterfly valve according to the magnitude of the pressure increase; when the pressure returns to the set value, the butterfly valve is closed again, and the exhaust of the small opening can avoid surge. Compared with the switch-type vent valve, opening the vent valve at a small angle can effectively avoid energy waste caused by excessive pressure relief.

[0016] Further optimized technical solution: A displacement sensor is configured in the linear motion mechanism driven by the motor. When the fan control system controls the electric push rod mechanism to extend, the displacement sensor detects the displacement value of the electric push rod mechanism, which can be converted into the rotation angle of the butterfly valve plate, that is, the valve opening. The electric push rod mechanism is extended and retracted by the motor drive, and the extension or retraction length is determined by controlling the power-on time.

[0017] A specific implementation scheme is that when the electric push rod mechanism extends 9 mm, the butterfly valve opens 6°; when the electric push rod mechanism extends 30 mm, the butterfly valve opens 20°.

[0018] A further optimized technical solution is to install an adjustable silencer on the outlet surface of the butterfly valve to reduce the noise coming out of the vent valve.

[0019] A more specific technical solution is that the adjustable silencer device includes a silencer installed on the outlet surface of the butterfly valve through a flange, a movable adjusting cover is installed on the silencer, a noise reduction orifice plate and an adjusting stud are provided on the silencer; a compression spring is provided between the adjusting cover and the silencer, and an adjusting nut is installed on the adjusting stud. The distance between the silencer and the adjusting cover is changed by adjusting the screwing depth of the adjusting nut, thereby adjusting the resistance of the gas outflowing channel, thereby reducing the outlet noise.

[0020] The implementation of the above series of technical solutions will give the fan products the following advantages: 1. The butterfly valve is used to control the fan venting, which has high reliability and low cost because the butterfly valve is a mature standard part; 2. The linear drive can realize the rapid opening and closing of the butterfly valve; 3. The opening of the butterfly valve can be continuously controlled, which is stable and reliable; 4. The exhaust channel of the air defense valve can be adjusted to reduce noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The column diagram used in the present invention is as follows: Figure 1 Blower equipment with vent valve Among them, 10 blower host; 40 chassis; 30 vent valve; 20 gas pipeline of the host air outlet Figure 2 A vent valve device Among them, 1. Electric push rod mechanism; 2. Connecting rod; 3. Bracket; 4. Butterfly valve; 5. Adjustable silencer Figure 3 Diagram of vent valve operation Figure 4 Vent valve device with adjustable silencer in control system Among them, 51. Adjustment cover; 52. Spring; 53. Muffler; 54. Mounting flange; 55. Adjustment nut; 56. Gas pipe of the main unit outlet; 57. Pressure detection port Specific embodiments Example

[0022] A specific implementation example is Figure 4 As shown in FIG. 1 , a vent valve device in an automatic control system is provided on a branch air flow pipeline on the side of the gas pipeline 56 at the blower outlet, such as Figure 2As shown, it contains a bracket 3 for installing loose parts, a butterfly valve 4, and an electric push rod mechanism 1 composed of a DC motor, a reduction mechanism, and a screw mechanism. The butterfly valve 4 and the electric push rod mechanism 1 are connected by a connecting rod 2, and the connecting rod 2 and the butterfly valve 4 and the electric push rod mechanism 1 are all connected by a rotating shaft; the electric push rod mechanism 1 is a mechanism that converts the rotation of the DC motor into linear motion, and the linear displacement in the electric push rod mechanism 1 determines the degree of opening of the butterfly valve 4; the motor drives and controls the movement of the electric push rod mechanism 1, and determines the extension or retraction length by controlling the power-on time; the control system converts the pressure detected by the pressure detection port 57 into the displacement of the electric push rod mechanism 1 controlled by the motor.

[0023] The electric push rod mechanism 1 of this embodiment is provided with a displacement sensor. When the fan control system controls the electric push rod mechanism to extend, the displacement value of the electric push rod mechanism extended detected by the displacement sensor can be converted into the valve plate rotation angle of the butterfly valve 4, that is, the valve opening, such as Figure 3 The vent valve operation diagram is shown. The electric push rod mechanism is extended or retracted by the motor drive, and the extension or retraction length is determined by controlling the power-on time. Based on the setting of various parameters, the final result achieved in this embodiment is: the electric push rod mechanism extends 9mm, the butterfly valve opens 6°; the electric push rod mechanism extends 30mm, and the butterfly valve opens 20°.

[0024] This embodiment uses an electric push rod mechanism as the driving mode of linear motion. The electric push rod mechanism is composed of a DC motor, a reduction mechanism, and a screw mechanism. The rotary motion can be converted into the linear motion of the push rod. The reduction mechanism can be adjusted to match different telescopic speeds. Similarly, a telescopic cylinder, a linear motor, and other driving devices can be used to drive the valve plate of the butterfly valve to rotate.

[0025] This embodiment adopts a mature butterfly valve to control the pressure relief and venting of the fan, which has high reliability and low cost; linear drive is adopted to realize rapid opening and closing of the butterfly valve, and the opening degree of the butterfly valve can be continuously controlled. Example

[0026] The second technical solution of the present invention implemented in the product is based on Example 1. Figure 4 As shown, an adjustable muffler 5 is installed on the outlet surface of the butterfly valve to reduce the noise coming out of the vent valve. The adjustable muffler includes a muffler 53 installed on the outlet surface of the butterfly valve through a flange 54, a movable adjustment cover 51 is installed on the muffler, and a noise reduction orifice plate and an adjustment stud are provided on the muffler; a compression spring 52 is provided between the adjustment cover 51 and the muffler 53, and an adjustment nut 55 is installed on the adjustment stud. The distance between the muffler 53 and the adjustment cover 51 is changed by adjusting the screwing depth of the adjustment nut, thereby adjusting the resistance of the gas outflow channel to reduce the outlet noise.

[0027] A series of vent valve devices in the automatic control system described in the present invention abandon the previous film seal and use mature butterfly valves to relieve the pressure of the blower host, which solves a series of problems existing in the prior art of blower equipment, thereby making the product seal reliable and low in cost; an electric push rod mechanism with a displacement sensor is used as the driving mechanism of the vent valve, which can respond quickly when the pipeline pressure fluctuates to avoid surge; the vent valve opening can be continuously adjusted to improve the operating reliability of the whole machine; a silencer structure is set downstream of the butterfly valve, and the vent valve noise can be adjusted according to the required flow rate to reduce the vent valve emptying noise.

[0028] The technical solutions covered by the present invention are not limited to the above-disclosed contents. The vent valve device in the automatic control system is not only suitable for blower equipment, but also suitable for all control systems that require pressure relief.

Claims

1. A vent valve device in an automatic control system, installed on a branch ventilation pipe connected to the side of the blower outlet pipe, characterized in that: The vent valve device and the pressure detection device on the blower main unit air outlet pipe cooperate in the control system of the blower equipment to realize automatic control; the vent valve device in the automatic control system contains a bracket for installing loose parts, a butterfly valve is installed on the bracket, and a butterfly valve control mechanism is also installed to open the butterfly valve and release the pressure according to the signal of the pressure detection device; the butterfly valve is coaxially connected to the branch ventilation pipe through a flange.

2. The vent valve device in the automatic control system according to claim 1, characterized in that: The butterfly valve control mechanism includes a motor and a linear motion mechanism driven by the motor, and also includes a connecting rod with both ends connecting the linear motion mechanism and the butterfly valve in the form of a rotating shaft; wherein, the control system converts the detected pressure of the blower outlet pipe into a signal to control the rotation of the motor, the rotation of the motor drives the linear motion, and the linear displacement determines the rotation angle of the valve plate of the butterfly valve through the connecting rod; the power-on time of the motor determines the length of the linear displacement.

3. The vent valve device in the automatic control system according to claim 2, characterized in that: The motor-driven linear motion mechanism is an electric push rod mechanism composed of a DC motor, a reduction mechanism, and a screw mechanism. The reduction mechanism can be adjusted to match different telescopic speeds to cope with various actual required butterfly valve opening and closing speeds; the electric push rod mechanism and the butterfly valve are connected by a connecting rod, and both ends of the connecting rod are connected by rotating shafts.

4. The vent valve device in the automatic control system according to claim 2, characterized in that: The motor-driven linear motion mechanism is a cylinder structure driven by compressed air.

5. The vent valve device in the automatic control system according to claim 2, characterized in that: The motor-driven linear motion mechanism is a linear motor that drives the valve plate of the butterfly valve to rotate.

6. The vent valve device in the automatic control system according to claim 2, characterized in that: A displacement sensor is arranged in the motor-driven linear motion mechanism. When the fan control system controls the electric push rod mechanism to extend, the displacement sensor detects the displacement value of the electric push rod mechanism, which can be converted into the rotation angle of the butterfly valve plate, that is, the valve opening. The electric push rod mechanism is extended or retracted by a motor, and the length of extension or retraction is determined by controlling the power-on time.

7. The vent valve device in the automatic control system according to claim 6, characterized in that: When the electric push rod mechanism extends 9mm, the butterfly valve opens 6°; when the electric push rod mechanism extends 30mm, the butterfly valve opens 20°.

8. A vent valve device in an automatic control system according to any one of the preceding claims, characterized in that: An adjustable silencer is installed on the outlet surface of the butterfly valve to reduce the noise coming out of the vent valve.

9. The vent valve device in the automatic control system according to claim 8, characterized in that: The adjustable silencer device includes a silencer installed on the outlet surface of the butterfly valve through a flange, a movable adjustment cover is installed on the silencer, and a noise reduction orifice plate and an adjustment stud are provided on the silencer; a compression spring is provided between the adjustment cover and the silencer, and an adjustment nut is installed on the adjustment stud, and the distance between the silencer and the adjustment cover is changed by adjusting the screwing depth of the adjustment nut, thereby adjusting the resistance of the gas when it flows out of the channel, thereby reducing the outlet noise.

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