Abstract: A toner separation apparatus includes a target, an inlet through which toner laden carrier enters to strike the target, an exit for carrier particles below the target, and an exit for toner particles downstream of the target. A filter can be positioned between the target and the toner exit, and a mesh to which the target is attached can be located between the inlet and the filter. The toner-laden carrier can be entrained by air driven by one or more impellers, which can be located within or without the apparatus, upstream or downstream of the target.

Abstract: A toner separation apparatus includes a target, an inlet through which toner laden carrier enters to strike the target, an exit for carrier particles below the target, and an exit for toner particles downstream of the target. A filter can be positioned between the target and the toner exit, and a mesh to which the target is attached can be located between the inlet and the filter. The toner-laden carrier can be entrained by air driven by one or more impellers, which can be located within or without the apparatus, upstream or downstream of the target.

Abstract: An apparatus and method for determining both the breakdown voltage and the conductivity of a particulate material, such as a developer material, is provided. In a preferred embodiment, the apparatus for determining breakdown voltage comprises a breakdown cell for storing a preselected quantity of the particulate material and a voltage breakdown ("VB") autometer, the VB autometer being adapted to apply a first voltage across at least portions of the preselected quantity of the particulate material. The VB autometer is capable of progressively varying the magnitude of the first voltage. A measuring circuit, for measuring a second voltage, is coupled to the voltage breakdown cell. When the second voltage substantially equals a preselected reference voltage, the first voltage substantially equals the breakdown voltage of the particulate material.

Abstract: Magnetically-responsive electrostatographic nickel carrier particles having semi-conductive and lower triboelectric charging properties are prepared by heat treating nickel particles in an ambient atmosphere as to provide the carrier particles with an oxide coating. More particularly, commercially available nickel particles are placed in a furnace and the particles are heat treated at a temperature of between about 600.degree. C. and about 1,000.degree. C. for a period of time of between about 5 and 10 minutes. When employed with finely-divided toner particles to develop electrostatic latent images in a magnetic-brush development apparatus, the treated carriers have been found to alleviate shorting problems and to provide developed images having lower background densities and higher resolution than prior carrier materials.

Abstract: A method of manufacturing spheroidized beads comprising the steps of introducing raw ore particles in the presence of an inert non-oxidizing carrier gas to a carbon arc plasma flame assembly to which is fed a controlled amount of oxygen and argon gas, melting the ore particles to form spheroidized droplets thereof, allowing the spheroidized droplets to fall by gravity in a substantially closed chamber having a controlled atmosphere wherein the droplets cool and solidify into beads, and collecting the beads.

Abstract: In preferred form, the inventive concept utilizes a carbon arc plasma flame assembly wherein magnetic ore particles are fed to the plasma flame assembly in the presence of a controlled, gaseous atmosphere. The plasma flame assembly comprises a cathode and at least two carbon anodes to which is fed oxygen gas in a controlled amount. Upon contact with the plasma flame, the ore particles become molten droplets which fall by gravity into a spheroidization column having a controlled atmosphere. As the molten droplets fall, they cool and become spheroidal particles. The chamber wherein the heating occurs is substantially sealed and is initially purged with inert gas. In addition, the spheroidization column is fitted with an exhaust system which maintains the integrity of the processing atmosphere and that of the spheroidized particles.