What Damages the Switching Speed of a One-Way Solenoid Valve?

The switching response speed of a one-way solenoid valve is a very important parameter; its meaning is the speed at the start and at closing. This needs attention in some special occasions or in devices with strict requirements, especially in occasions that require strict control of time and frequency, where its response time must be less than 0.05 seconds. Based on our experience, we have summarized three major factors: valve core, power circuit, and magnetic loss. The overall switching of the one-way solenoid valve relies on electromagnetic force and torque to drive the opening and closing of the valve core.

(1) Coil movement time lag

Due to the mass of the valve core of a normally closed 2-way 2-position solenoid valve, an inertial torque is generated throughout its movement, causing an operation delay. The way to reduce the operation delay is to increase the thrust and reduce the mass of the valve. In this respect, a shift solenoid valve shows an obvious difference; in many cases a lower gear produces a slower speed effect, and adjusting it to a strong gear can increase the speed, but this improvement is relatively weak.

(2) Power supply delay

Through the basic theory of the electromagnetic field, we find that the current of the electromagnetic coil cannot increase immediately. Therefore, when the valve opens, the electromagnetic force cannot increase quickly, so the solenoid valve cannot overcome sliding friction and elastic force to quickly open the valve body. When the valve closes, the torsion spring cannot immediately release the electromagnetic force, thereby causing a delay in the current. The main parameter of time, τ = L/R, is related to the coil resistance, working voltage, relative permeability of the magnetic material, and other factors. Here it should also be noted that a pneumatic 2-way 2-position solenoid valve is somewhat different; because its own characteristic is a different pressure, the voltage requirements are also different.

(3) Eddy current loss lag

Due to the magnetic loss of eddy current loss and the eddy current in the equivalent ring, the solenoid valve will generate a large amount of loss during operation, thereby jeopardizing the switching rate of the valve. It should be noted that a no-consumption state will appear when using a piston-type normally open solenoid valve, but this is only due to manual reasons; in other respects it is about the same, so it still needs attention.