Corona wire

Two-stage precipitators consist of separate sections for particle charing and collection. Particle charging is realized with corona wires between grounded metal plates. The collection of particles rakes place in a system of parallel plate electrodes of opposite polarities. Two-stage precipitators are typically used in indoor air cleaning and light industrial applications. 

According to this equation, the electric field is constant in the region some distance from the corona wire. 

Secondary gas stream positively charged by a high-voltage platinum Corona wire... 

Secontary gas stream positively charged by a high-voltage Positive charge platinum corona wire transferred to analyte particles by charged opposing secondary gas stream... 

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... 

There are two types of corona assemblies, those that contain a corona wire and those that contain a corona roller. The corona wire is a small diameter wire that is charged by the high-voltage power supply. The wire is located in a special notch in the floor of the laser printer (underneath the EP print cartridge). The corona roller performs the same function as the corona wire, except that it s a roller rather than a wire. Because the corona roller is directly in contact with the paper, it supports higher speeds. It is for this reason that the corona wire isn t used in laser printers much any more. 

C. The corona assembly gets the toner from the photosensitive drum onto the paper. For some printers, this is a corona wire, and for others, it is a corona roller. 

To check if the corona assembly is causing the problem, open the cover and examine the wire (or roller, if your printer uses one). The corona wire is hard to see, so you may need a flashlight. You will know if it s broken or missing just by looking (it will either be in pieces or just not there). If it s not broken or missing, the problem may be related to the HVPS. 

The corona wire (or roller) is a relatively inexpensive part and can be easily replaced with the removal of two screws and some patience. 

Another possible cause of vertical black lines is a dirty charge corona wire. A dirty charge corona will prevent a sufficient charge from being placed on the EP drum. Since the EP drum will be almost zero, toner will stick to the areas that correspond to the dirty areas on the charge corona. 

Vertical white lines running down all or part of the page are relatively common problems on older printers, especially ones that don t see much maintenance. They are caused by some foreign matter (more than likely toner) caught on the transfer corona wire. The dirty spots keep the toner from being transmitted to the paper (at those locations, that is), with the result that streaks form as the paper progresses past the transfer corona wire. 

The solution is to clean the corona wires. LaserJet Series II printers contain a small corona wire brush to help in this procedure. It s usually a small, green-handled brush located near the transfer corona wire. To use it, remove the toner cartridge and run the brush in the charge corona groove on top of the toner cartridge. Replace the cartridge and use the brush to brush away any foreign deposits on the transfer corona. Be sure to put it back in its holder when you re finished. 

A. If, after cleaning all the internal components of a printer, it starts printing blank pages, most likely the transfer corona wire is damaged. Care must be taken when cleaning this, as it is a delicate component. 

A. After the laser writes the image to a photosensitive drum, the transfer corona wire charges the paper so that the toner is pulled from the drum to the paper. See Chapter 7 for more information. 

A precipitator consists of two bus sections, each with five plates (four passages) in a field (see Figure 70). The corona wires between any two plates are independently controlled so that the remainder of the unit can be operated in the event of a wire failure. The following operating conditions exist ... 

Tungsten charger wires (Corona wires) for laser printers, photocopiers, FAX machines, etc. (W, gold-plated, Pt-clad W). 

The term "electrostatic technique" tends to be usually associated in many minds with Leyden jars, high voltages and corona wires. There were indeed attempts in the late 1930 s and 1940 s to transfer paste type inks — mainly letterpress -across a gap by means of high voltages, air ionization and ion bombardment. The objective was to eliminate pressure and to permit the use of light weight presses. None of these schemes have found commercial applications. 

Corona-charged aerosol (CAD) Universal use nebulizer technology like ELSD and detection of charges induced by a high-voltage corona wire Low ng... 

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