Abstract: A small quantity of electron attaching gas is introduced into the corona region of an electrical ionizer to stabilize the corona in the otherwise electron non-attaching nitrogen gas. The corona region is closely localized at emitter points so the quantity of electron attaching gas is very small. Clean-dry-air is preferably used as the purge gas but other gases such as oxygen and carbon dioxide may be used. The small quantity of electron attaching gas may be introduced either through a hollow needle emitter or an external purge gas (sleeve about the needle, or by using a gas purge nozzle).

Abstract: An ionizer creates a corona current distribution having a balanced flow of positive and negative ions in a variable ion mobility gaseous environment. The balanced flow of positive and negative ions are directed toward a workspace or target located in the gaseous environment and downstream from the ionizer. The ionizer includes a corona electrode, a counterelectrode, a corona-free dc bias electrode, and a control circuit. The corona electrode has a negative polarity. The counterelectrode has an ion collecting surface. The corona-free dc bias electrode has a positive polarity. The control circuit controls the output of the corona-free electrode so as to cause a balanced flow of positive and negative ions to be emitted from the ionizer and directed towards the workspace or target. In this manner, a static-free environment is created at the workspace or target.

Abstract: An ionizer that creates a corona current distribution having a balanced flow of positive and negative ions in a variable ion mobility gaseous environment, such as an environment of substantially nitrogen. The balanced flow of positive and negative ions is directed toward a workspace or target located in the gaseous environment downstream from the ionizer. The ionizer includes a counterelectrode, a positive ion emitter, a negative ion emitter, and a control circuit. The counterelectrode has at least two spatially isolated collecting surfaces. The positive and negative ion emitters are spatially isolated from each other so that the outputs of each of the emitters do not reach the other emitter.

Abstract: An ionizer creates a corona current distribution having a balanced flow of positive and negative ions in a variable ion mobility gaseous environment. The balanced flow of positive and negative ions are directed toward a workspace or target located in the gaseous environment and downstream from the ionizer. The ionizer includes a corona electrode, a counterelectrode, a corona-free dc bias electrode, and a control circuit. The corona electrode has a negative polarity. The counterelectrode has an ion collecting surface. The corona-free dc bias electrode has a positive polarity. The control circuit controls the output of the corona-free electrode so as to cause a balanced flow of positive and negative ions to be emitted from the ionizer and directed towards the workspace or target. In this manner, a static-free environment is created at the workspace or target.

Abstract: A high voltage sensor that is adapted to be connected to a terminal. The terminal is disposed in a housing having an outer surface and having a chute extending inwardly from the outer surface to a distal position inside of the housing. The high voltage sensor includes a sensor body that is adapted to be inserted into the chute and has a distal end and a proximal end. A contact is mounted on the distal end of the sensor body. An indicator circuit is substantially enclosed in the sensor body and includes an indicator lamp. The indicator circuit is electrically connected to the contact and the terminal is in electrical contact with the contact upon insertion of the sensor body into the chute of the housing.

Abstract: Germanium needles as emitter electrodes for use in low particle generating gas ionizers in general and static eliminators in particular. They oxidize with minimal incorporation of nitrogen, and the negative polarity emitters oxidize at a greater rate than the positive polarity emitters. Negative polarity silicon emitters generate several orders of magnitude greater particle emissions than either positive or negative germanium electrodes. The mean particle size is about 0.015 &mgr;m. No particles were shed from these needles. Lowest particle generation is achieved when germanium electrodes are purged with dry air.

Abstract: An improved corona electrode for use in an electrostatic precipitator of the parallel plate type that includes the addition of a second corona producing electrode adjacent to and in common plane with a needle-type corona producing electrode secured to a vertical edge of the collecting plates. By locating the two corona electrodes a specific distance apart forms a highly efficent corona electrode pair in proper proximity to a collection plate, gas-borne particles, even very high resistivity particles are more effectively charged, and their collection is promoted through both electrostatic and hydrodynamic collection mechanisms.