Apparatus for use in applying electrostatically charged coating material

An apparatus for use in applying electrostatically charged coated material to a workpiece, said apparatus comprising a spray gun from which a flow of electrostatically charged coating material is directed toward a workpiece, a source of electrostatically charged coating material, and a coating material conduit connected with said spray gun and said source of electrostatically charged coating material, said coating material conduit including an electrical conductor element which extends from said spray gun and is connected with an electrical ground adjacent to said source of electrostatically charged coating material, wherein said coating material conduit includes an inner layer which at least partially defines a passage through which electrostatically charged coating material is conducted and an outer layer which extends around said inner layer, said electrical conductor element includes an electrically conductive layer which extends around said inner layer and is disposed between said inner and outer layers.

An apparatus for use in applying electrostatically charged coating material to a workpiece, said apparatus comprising a spray gun and conduit means for conducting a flow of electrostatically charged coating material to said spray gun, said conduit means including an inner layer which at least partially defines a passage through which the flow of electrostatically charged coating material is conducted, said inner layer being formed of a material which is electrically insulating and chemically nonreactive with the electrostatically charged coating material, an electrically conducting layer which extends around said inner layer and is formed of an electrically conductive material dispersed within an elastomeric material, and an outer layer which extends around said electrically conducting layer and is formed of an abrasion resistant material.

An apparatus for use in conducting electrostatically charged coating material to a spray gun, said apparatus comprising a flexible conduit having a first layer formed of a polymeric material, said first layer of polymeric material being electrically insulating and chemically nonreactive with the electrostatically charged coating material, a second layer of elastomeric material disposed around said first layer, said second layer of elastomeric material being electrically insulating, a third layer of elastomeric material containing an electrically conductive material and disposed around said second layer, said third layer of elastomeric material and conductive material being electrically conductive, and a fourth layer of polymeric material extending around said third layer of elastomeric material, said fourth layer of polymeric material being abrasion resistant and electrically insulating.

An apparatus for use in applying electrostatically charged coating material to a workpiece, said apparatus comprising a spray gun having an electrically conductive handle portion engageable by an operator and an extension portion which directs a flow of electrostatically charged coating material toward the workpiece, an air conduit to conduct a flow of air to said handle portion of said spray gun, a coating material conduit to conduct a flow of electrostatically charged coating material to said spray gun, said coating material conduit extends through said handle portion of said spray gun into said extension portion of said spray gun, and electrode means for receiving an electrical charge from the electrostatically charged coating material and strengthening an electrostatic field between said spray gun and the workpiece during application of electrostatically charged coating material to the workpiece.

A flexible hose for carrying coating material to an electrostatic coating applicator, the hose having a circular cross-section and a radius "r" from the center of the cross section to the outside diameter of the hose wall, the hose wall including an electrically insulative layer comprised of a material having a Shore A hardness of 75 or less for at least a wall thickness of 0.20 r, an inner layer in contact with the paint being constructed from high density polyethylene or any polyolefin and an outer conductive layer, said insulative layer being located between said outer conductive layer and said inner layer.