Air control Needle Valve can be divided into single gas control and double gas control structure principle, dual gas control valve has memory performance, even if the control signal is gone, the valve output will remain in the signal before the state (no reset). The most common use is the pressurized control of the air control needle valve.
Single-pneumatic Needle Valve (two), single-pneumatic control valve is the principle of the valve at both ends of the control signal port, the introduction of alternating gas control signal to control the main valve switching work. In the output state is generally determined by the control signal, if the control signal is not, the spool in the spring or spring under the action of the pressure will be in the original position.
When the control signal, the spool is pushed by the gas control signal to the other end can be switched, when the valve at the left end of the signal without the left end of the introduction of gas signal, the spool was pushed to the right (switch); when the left side of the Needle Valve without signal right Gas signal, the spool is pushed to the left (toggle)
The At the end of the valve, the control signal can not be introduced at the same time. Double gas needle valve in addition to the middle of the middle, both ends of the alternating into the gas control signal and the two valves to switch between the same function; but both ends of the control signal is revoked, the spool will not stay in a certain end , But back to the original intermediate position and working state.
The above is Xiaobian introduced single gas control needle valve and double pneumatic needle structure and the role of the principle of the difference.