Apparatus for coating elongated articles

Claim 2

The coating device of claim 1 further comprising means providing a closed system for recirculating a portion of the dust entering said chamber from said dusting tube back into said dusting tube.

Claim 3

The coating device of claim 1 wherein said means for introducing dustlike particles into said dusting tube as aforesaid comprises a blower, means for metering coating dust into said blower, and conduit means leading from said blower to openings in opposite sides of said dusting tube intermediate the ends thereof.

Claim 4

The coating device of claim 4 further comprising a manifold into which the coating dust is metered before being drawn through said blower, and a vacuum conduit interconnecting said chamber with said manifold through which a portion of the dust entering said chamber from said dusting tube is pulled by said blower for recirculation back into said dusting tube.

Claim 5

The coating device of claim 1 further comprising guide means for guiding an elongated workpiece through said dusting tube in spaced relation from the wall thereof.

Claim 6

The coating device of claim 1 further comprising a main frame, and means mounting said coating device for limited vertical movement on said main frame.

Claim 7

The coating device of claim 7 wherein said last-mentioned means comprises a carriage having sliding connections with vertical supports on said main frame, a winch mounted on said main frame and a cable interconnecting said winch with said carriage.

Claim 8

The coating device of claim 7 wherein said main frame is mouNted on casters to facilitate movement from one place to another.

Claim 9

The coating device of claim 1 further comprising means associated with the bottom of said chamber for collecting the dust particles that settle to the bottom.

Claim 10

The coating device of claim 1 further comprising a pair of vertically spaced dusting manifolds within said chamber adjacent one end of said dusting tube, each of said manifolds having a plurality of spaced apart apertures therein for directing dust at opposite sides of a workpiece passing therebetween, and means for introducing coating dust into said manifolds under pressure for discharge through said apertures.

Claim 11

The coating device of claim 1 further comprising means for vibrating said chamber and dusting tube contained therein to shake loose any dust adhering thereto.

Claim 13

The device of claim 13 wherein said guide means supports the workpiece in spaced relation from the wall of said dusting tube during such passage therethrough to permit application of a uniform coating around the entire periphery of such workpiece.

Claim 14

The device of claim 13 wherein said entrance and exit openings are larger than the workpiece passing therethrough and means are provided for precluding the escape of dust through said openings.

Claim 15

A dusting device comprising an enclosure, a horizontal dusting tube mounted within said enclosure spaced from the walls of the latter, said dusting tube being of a length substantially greater than the size of the opening therethrough, said enclosure having openings therein aligned with the ends of said tube for passage of a continuously travelling elongated workpiece therethrough, blower means for introducing a flow of air to said tube intermediate its ends and discharge from both ends into said enclosure, means for supplying finely comminuted material to such air flow for dusting on such travelling workpiece, exhaust means communicating with the upper side of said enclosure for withdrawing air and a portion of such comminuted material flowing from the respective ends of said tube and recirculating them to said blower means, and collector means at the bottom of said enclosure for collecting comminuted material dropping out of the suspension therein.

Claim 16

A coating device comprising an open-ended dusting tube, means for introducing a flow of dustlike particles into said dusting tube to provide a dust suspension therein, an enlarged chamber completely surrounding said dusting tube for confining the dust suspension exiting from the open ends of said dusting tube, said means for introducing dustlike particles into said dusting tube as aforesaid comprising a blower, means for metering coating dust into said blower, and conduit means leading from said blower to opposite sides of said dusting tube, a manifold into which the coating dust is metered before being drawn through said blower, a vacuum conduit interconnecting said chamber with said manifold through which a portion of the dust entering said chamber from said dusting tube is pulled by said blower for recirculation back into said dusting tube, and an open-ended cylindrical exhaust member within said chamber, said vacuum conduit being connected to said cylindrical exhaust member intermediate the ends of the latter, the axis of said cylindrical exhaust member being parallel to the axis of said dusting tube to direct the vacuum pulling force toward the ends of said dusting tube.

Claim 17

A coating device comprising an open-ended dusting tube, means for introducing a flow of dustlike particles into said dusting tube to provide a dust suspension therein, an enlarged chamber completely surrounding said dusting tube for confining the dust suspension existing from the open ends of said dusting tube, an open-ended cylindrical exhaust member within said chamber, a vacuum conduit connected to said cylindrical exhaust member intermediate the ends of the latter, and means for creating a vacuum in said vacuum conduit to exhaust a portion of the dust entering said chamber from said dusting tube and recirculating such dust back into said dusting tube.

Claim 18

The coating device of claim 18 wherein the axis of said cylindrical exhaust member is parallel to the axis of said dusting tube to direct the vacuum pulling force toward the ends of said dusting tube.