Abstract: A dense phase pump for particulate material includes a pump chamber wherein material flows into the pump chamber under negative pressure and flows out of the pump chamber under positive pressure. A plurality of pinch valves are provided to control flow of material into and out of the pump chamber. The pinch valves are operated independent of each other and of the pump cycle rate. A modular design of the pump is provided.

Abstract: A nozzle for a powder spray gun optionally includes an internal filter that allows air to be added to the powder flow within the nozzle shell. The nozzle may optionally include an off-axis outlet slot relative to a main flow axis of the powder into the nozzle shell so that powder encounters an obstruction before exiting through the outlet slot.

Abstract: A supply or feed center for dry particulate material is modular in design with an application module and an exhaust module, along with optimal cabinet modules such as a pump cabinet module. The application module is partitioned into an application section and a utility section, both of which communicate with the exhaust module. An air diverter may be used to change relative air flow into the two sections, and in one embodiment is a swingable door. The exhaust module may include a self-contained exhaust system including after filters, motor, fan and final filters, or may share energy from a remote exhaust system. An inventive suction device is also provided to extract material from a hopper.

Abstract: An apparatus for emptying powder from a container, such as an original shipping box includes a support having a vibrating unit for loosening the powder within the container. A powder pick-up tube and an attached powder pump draw powder from the container and transfer the powder to a powder spray gun. The lower end of the pick-up tube includes a positively pressurized fluidization unit for locally fluidizing the powder at the pick-up tube inlet. The pressurized fluidization unit primarily assists in providing a consistent draw of powder up the pick-up tube.

Abstract: A quick color change powder coating system has a powder supply, a powder pump that receives powder from the powder supply through a suction pick-up tube, a spray gun and a powder hose that connects the pump to the gun. The apparatus includes a purge air switch assembly and a first air source that provides air at purge pressure to a first inlet of the purge air switch assembly. A second air source provides flow rate air to a first pump inlet and atomizing air to a second inlet of the pump via a purge air switch assembly. Powder is drawn up the tube and into the pump by suction produced by flow rate air into the pump. A purge inlet is associated with the powder inlet to the pump. The purge air switch assembly operates in response to a purge control signal to connect purge air to the atomizing inlet at the pump and to the pump's purge inlet; whereby the pump, hose and gun can be purged at the same time.

Abstract: A quick color change powder coating system has a powder supply, a powder pump that receives powder from the powder supply through a suction pick-up tube, a spray gun and a powder hose that connects the pump to the gun. The apparatus includes a purge air switch assembly and a first air source that provides air at purge pressure to a first inlet of the purge air switch assembly. A second air source provides flow rate air to a first pump inlet and atomizing air to a second inlet of the pump via a purge air switch assembly. Powder is drawn up the tube and into the pump by suction produced by flow rate air into the pump. A purge inlet is associated with the powder inlet to the pump. The purge air switch assembly operates in response to a purge control signal to connect purge air to the atomizing inlet at the pump and to the pump's purge inlet; whereby the pump, hose and gun can be purged at the same time.

Abstract: An improved apparatus for applying coating material includes a spray head having a housing which encloses a deflector. The deflector and housing cooperate to form a plurality of coating material flow channels which diverge in a direction of flow of coating material through the spray head. The deflector and housing cooperate to define a long thin outlet with relatively wide channel outlet sections at opposite ends of the outlet. An electrode assembly includes an electrode element having a long thin surface area which extends between opposite end portions of the long thin outlet and is exposed to the flow of coating material through the outlet. A wear tube encloses a portion of the electrode assembly and connects the deflector with the housing. The electrode element may be a plate which is molded into the deflector with a minor edge portion of the plate exposed to the flow of coating material.

Abstract: An apparatus for use in directing a flow of air with particles entrained therein toward a workpiece includes a nozzle and a deflector. The nozzle has a passage with a noncircular cross sectional configuration. The deflector has an outer side surface with a circular cross sectional configuration. A flow of air with particles of powder entrained therein is conducted along outer surface areas on the deflector at a first volumetric flow rate. A flow of air with particles of powder entrained therein is conducted along outer surface areas on the deflector at a second volumetric flow rate which is greater than the first flow rate. The deflector includes a porous member which is releasably connected with a main portion of the deflector to facilitate cleaning and provide access to the interior of the deflector. Seal members are provided between an electrode sheet, the porous member, and the main portion of the deflector.

Abstract: A particle spray apparatus includes a spray gun having a deflector connected with a housing assembly. An electrode arrangement extends from the housing assembly into the deflector and is exposed to the flow of air with particles entrained therein to electrostatically charge the particles. The electrode arrangement is exposed to a flow of fluid to remove contaminants which may accumulate around components of the electrode arrangement. Accumulation of particles on an end surface of the deflector is discouraged by a flow of fluid from a chamber in the deflector through a porous member. The flow of fluid from the chamber is also conducted through a porous electrode sheet which extends along the porous member. Due to the relatively high voltage conducted through the electrode arrangement, an arc may tend to form in a passage along which fluid is conducted to the electrode arrangement. To prevent this from occurring, the passage through which fluid is conducted to the electrode arrangement is relatively long.

Abstract: A spray gun with a powder spray nozzle sprays a pattern of coating material through specified discharge slot configurations to evenly coat a recess and/or the surface of a substrate. One discharge slot configuration, having two intersecting slots disposed at substantially sixty degree angles to each other, can be rotated to change the width of the coating being applied within the recess. The other slot configuration, having at least five radial slots and a substantially circular bore extending through the intersection of the slots, is effective to coat both the recess and the flat surface of the substrate.

Abstract: An electrostatic powder spray gun includes a hose purge adapter connected in the hose line that supplies powder to the gun. The hose purge adapter is connected to a supply of purge gas and allows the powder flow path in the hose line and the powder flow path in the gun to be quickly and conveniently purged of accumulations of powder. By facilitating purging of the powder flow path, the purge adapter prevents accumulations of powder that may tend to come loose as a soft lump of powder, usually different in color, and cause an imperfection on the surface of the object being coated. The purge adapter also reduces the collections of powder in the flow path in the hose line which facilitate a grounding path by the powder, resulting in possible shocks to the operator and in a high current draw into the gun which can result in poor transfer efficiency.

Abstract: Apparatus for coating the endmost threaded section of a pipe with corrosion resistant powder coating material by rotating the pipe and spraying the section to be coated with electrostatically charged, air-entrained powder through two stationary nozzles, one of which is directed at the section to be coated, and the other of which is directed at the chamfered end of the pipe. To prevent overspray of the powder from contacting the pipe adjacent to the area to be coated, a pair of air nozzles are directed at the area of the pipe adjacent to the area to be coated.

Abstract: A pneumatic powder collector for determining the transfer efficiency of a powder spray system comprises a funnel for directing powder into a sealed collection chamber. A vacuum is drawn on this chamber by an air flow amplifier having an air flow inlet open to the chamber and an exhaust open to atmosphere. Contained within the chamber there is an air permeable powder collection bag having an inlet open to the funnel so that air entrained powder drawn into the funnel is collected in the bag. The amount of vacuum drawn on the chamber is controlled by a pressure regulator through which high pressure air is supplied to the air flow amplifier so that the vacuum is just sufficient to pull all powder sprayed by a spray gun of the spray system into the chamber without increasing the flow of powder from the gun.