The working principle of static eliminator
The working principle of static eliminator
According to a survey by the Bureau of Labor Safety and Health Research, high-tech industries such as semiconductors, electronics, and panels and traditional industries such as papermaking, textiles, printing, chemistry, chemicals, petrochemicals, rubber, plastics, power electronics, food, etc. Process operations such as sheet rolling, material (liquid, gas, powder) conveying, coating, printing, crushing, drying, peeling, spraying, packaging, mixing and stirring, filtration and screening may all generate static electricity, resulting in electrostatic shock, Accidents such as fire and explosion, poor product quality and equipment insulation damage. In the survey, it was pointed out that 19% of domestic manufacturers had damaged products or equipment due to electrostatic accidents, 33% had electric shocks to personnel, and 5% had fires and explosions. Generally speaking, the electric shock caused by static electricity will only cause people to feel pain and fright, and there are no other sequelae. Secondary disasters caused by falls, etc. In addition, the percentage of fire and explosion is not high, but its destructive power is strong. As long as there is a fire or explosion, it is enough to cause serious losses and irreparable regrets.
Therefore, in the automation industry equipment, there are more and more anti-static or anti-static products. However, most people do not know much about the working principle of electrostatic eliminators.
corona discharge
formed along the edge of the electrode. Due to the excessive electric field strength, the non-conductive medium is broken down, the resistance of the insulator drops rapidly, and then part of the insulator becomes a conductor, and the resulting discharge phenomenon often occurs around the high-voltage wire or near the tip of the charged body, that is, tip discharge.
Tip discharge is the most common discharge method for static eliminators on the market. The main method of generating ions is to pass high-voltage electricity through the tip of a tungsten steel discharge needle, and the surrounding air is ionized by the electric field generated by the conductor, and then compressed air or The flowing air created by the fan brings ions to the workpiece or product for electrostatic neutralization.
The common discharge forms of static eliminators on the market are the following three:
DC direct current discharge method
Principle: The number of discharge needles must be an even number (2.4.6.8...), and the arrangement is in pairs, one of which releases positive ions and the other releases negative ions.
advantage:
Generates more ions.
The elimination time is shorter (that is, the elimination time is fast).
shortcoming:
A "reverse electrification" condition may occur.
ION BALANCE is unstable.