High-precision gas mass flow control valve

Abstract

The invention discloses a high-precision gas mass flow control valve. A PLC controls a servo motor driver to serve as a power source; a servo motor rotates correspondingly after receiving a signal; arotating shaft of the servo motor drives a valve element to move axially through a lead screw and a limiting nut, then the opening-closing degree of the valve element and a valve seat is controlled, and finally the gas flow is controlled; a gas flow meter and a pressure sensor are connected to a gas inlet of a valve body; a flow signal output by the gas flow meter and a pressure signal detected bythe pressure sensor serve as feedback signals, the PLC receives the feedback signals and then compares the feedback signals with a system instruction, makes a judgment, and sends a new instruction tothe servo motor, and therefore flow and pressure closed-loop control is formed; and finally, closed-loop control over the position of the valve element reaches high-precision flow control.

Description

technical field [0001] The invention relates to a high-precision gas mass flow control valve, which belongs to the technical field of control valves. Background technique [0002] In the prior art, flow control valves include pneumatic valves, hydraulic valves, electromagnetic switch valves, electric gate valves, etc., which are characterized by high precision for small range control valves and low precision for large range control valves. Among them, the precision of the large-scale gas flow valve is not enough, so it is mainly based on switch control. The measurement accuracy of the existing proportional solenoid valve on the market is lower than ±0.5% of the full stroke; in addition, the stepping motor drives the gate valve during the axial expansion and contraction process In the middle, it is prone to jamming phenomenon; and the threaded screw and nut also have self-locking phenomenon, and there is a problem that the motor is locked and cannot be restarted. Contents o...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, flow control valves include pneumatic valves, hydraulic valves, electromagnetic switch valves, electric gate valves, etc., which are characterized by: the control valve with a small range has high precision, and the control valve with a large range has low precision

Among them, the precision of the large-scale gas flow valve is not enough, so it is mainly based on switch control. The measurement accuracy of the existing proportional solenoid valve on the market is lower than ±0.5% of the full stroke; in addition, the stepping motor drives the gate valve during the axial expansion and contraction process In the middle, it is prone to jamming phenomenon; and the threaded screw and nut also have self-locking phenomenon, and there is a problem that the motor is locked and cannot be restarted.

Images