Corona charging devices

A variable air flow (1.5-8 m /h) with NaCl particles (diameter 0.1-0.5 micron) is produced and guided through the measuring section. The particles can be charged by a corona charging device. 

Step 1 Charging. An electrostatic charge is uniformly distributed over the surface of the drum in the dark by a corona-producing device correctly called a screened corotron or scorotron for short. How well the drum is charged depends on several variables. The most important are listed here ... 

A photoinduced discharge apparatus includes a corona charging unit, an exposure system, and a noncontacting voltmeter. A grid is usually positioned between the corona wires and the sample to control the corona current. The apparatus is normally provided with a beam splitter and radiometer. The surface potentials are determined by a capacitively coupled probe and FET amplifier. The time derivative of the voltage can be obtained electronically or by numerical differentiation on a computer. When a time resolution greater than 10 ms is adequate, commercial voltmeters, for example, Monroe Electronics Isoprobe or Trek Electrostatic voltmeters, can be used. These are feedback devices, based... 

Some of the interfaces meeting the photoreceptor are obvious its surface encounters ionized gas which serves to deposit or remove corona charge, the developer mass, the transfer sheet, and cleaning devices. Other interfaces with essential functions are found in the internal structure of the photoreceptor itself. Let us now look at these in some detail. 

The particle collection efficiency of these air filters can be enhanced by the static charging of the fibres, " and this can be realised by using mixed fibres of various layouts of electret filters " such additional filtration mechanism is more useful for filters used in respiration devices.The ionic species generated by the negative polarity corona (CO, ) seem to be more effective for corona charging of a PP nonwoven... 

An AC corona discharge in the throat leads to a cloud of charged droplets whose large momentum allows very long travel distances. Multiple devices for eliminating static discharges in powder silos have been tested [41] but the tests did not address typical flow rates for large capacity, dense phase pneumatic transfer operations. 

Experimental results obtained in Ref. [4] illustrate clearly that devices based on thin wires provide a more uniform charge distribution and thus may be recommended for XTOF spectroscopy. In order to control the sample initial voltage, a biased grid is inserted between the corona emitter and the floating surface of the sample. 

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