Abstract: An apparatus for electrostatically coating conductive articles with powder. A mixture of powder and air is delivered through a passage of uniform cross-section and a short section of rotating tube to a rotating bell of nonconductive material having a surface angle with the axis of 50.degree. to 90.degree.. The powder is directed from a nozzle over the bell surface and the entraining air is dissipated laterally. The powder is discharged from the bell into an electrostatic field where the particles acquire a charge and are attracted to and deposited on the grounded articles. A pneumatic jet pump for entrailing the powder particle in an air stream has a nozzle and venturi so related that the expanding air from the nozzle blends with the expanding portion of the venturi.

Abstract: A method and apparatus for correcting imbalance occurring in pneumatic tires during their manufacture. Correction is made by depositing on the inside surface of the tire, at a balance-correcting position, a measured quantity of an uncured, quick-curing, urethane or other liquid elastomer composition which bonds to such surface when cured, and curing the composition in place against the surface. The surface is cleaned in advance, as by washing, scrubbing, and/or abrading, to remove mold release agents and the like and to expose the bare rubber of the tire wall for bonding. The elastomer is desirably deposited in a pool, but may be dispensed in a stream of air or other gas directed toward the deposit. The air reduces the thickness of the pool and feathers its edges and thereby reduces the discontinuity between the deposited material and the tire surface, and promotes bonding.

Abstract: A system for electrostatic deposition of a coating on an article from a charging device includes a direct current high voltage supply having first and second terminals across which the high voltage is impressed. The article to be coated is held at a potential substantially equal to the potential on one of the high voltage terminals. The article is suspended for relatively free movement toward and away from the device. The system includes a high-speed switch coupled between the high voltage terminals and a control circuit for controlling the switch. A sensing resistor in the high voltage output circuit monitors the current between the high voltage terminals. The control circuit includes a slope-detecting or fixed difference circuit responsive to the sensed current to detect too-rapid changes therein, such changes being indicative of close proximity of the article to the charging device and the possibility of high voltage arcing therebetween.

Abstract: Apparatus for determining the amount and location of imbalance in an article which is to be balanced about its axis includes a table for receiving the article and for positioning its axis. The table is supported upon a base for substantially free tilting movement generally about a point on a vertically extending axis defined by the base. A number of proximity transducers for sensing the orientation of the table relative to the base are provided. A pair of force coils positioned in quadrature about the axis between the base and the table are responsive to the proximity transducers to apply forces between the table and the base to bring the table and the article which rests thereon into a substantially neutral orientation with respect to the base. The method of the present invention comprises the steps of placing the article on the table with the article axis at a predetermined position thereon.

Abstract: An apparatus for electrostatically coating conductive articles with powder. A mixture of powder and air is delivered through a passage of uniform cross-section and a short section of rotating tube to a rotating bell of nonconductive material having a surface angle with the axis of 50.degree. to 90.degree.. The powder is directed from a nozzle over the bell surface and the entraining air is dissipated laterally. The powder is discharged from the bell into an electrostatic field where the particles acquire a charge and are attracted to and deposited on the grounded articles. A pneumatic jet pump for entraining the powder particle in an air stream has a nozzle and venturi so related that the expanding air from the nozzle blends with the expanding portion of the venturi.

Abstract: Electrostatic deposition of air atomized liquid coating materials by adjusting the conductivity of the coating material and the voltage applied thereto so that virtually no air ionization occurs. Thus, essentially all of the current reaching the object to be coated is carried by the sprayed material thus minimizing the charge build-up on the subject, and eliminating charge accumulation on ungrounded objects out of the spray zone.

Abstract: A fiber cutter for cutting lengths of glass fibers and glass rovings into short lengths includes a cutter roller carrying a plurality of cutting blades and shaped annular means cooperatively associated with a resilient back-up roll means. In operation the force executed between the cutter roller and the back-up roller controls the spacing between the rollers by forcing the shaped annular means into the resilient surface of the back-up roller means. In addition to permitting control of spacing, the coaction of the cutter roller with its shaped annular means and the resilient back-up roll means holds the rollers in alignment, reduces the bounce between the rollers as the blades engage and pass over the back-up roll means and permit force to be used to build the blades in engagement with the back-up roll means without blade breakage.

Abstract: The projecting nozzle for powder coating is a device for dispersing finely divided powder paint particles in a pattern controlled by swirling air without accumulating unwanted powder particles. A hollow nozzle is located concentrically to a guide member forming a gap through which the powder is projected. Orifices and, or slits located in the guide member direct compressed air in a swirling motion. A porous plate, forming the front of the guide member allows air to pass therethrough and thereby prevents the accumulation of powder particles.