Process for electrodepositing mica on coil or bar connections and resulting products
First Claim
1. A process for depositing an insulating coating on bare portions of electrical connection members comprising the steps of(a) immersing the bare electrical connections in an aqueous electrodeposition composition consisting essentially in weight percent of 5-35% of particulated mica, 0.2-2% of a water soluble anionic resin binder as calculated in resin solids, 0.001-0.20% of an electrolyte, up to 0.3% of a nonionic surfactant and a polar solvent;
- (b) electrodepositing said composition on the bare electrical connections and forming a dry micaceous coating of substantially uniform thickness, said coating being porous and containing a sufficient amount of binder to hold the mica particles together;
(c) impregnating the porous coating with an impregnative resin varnish; and
(d) subjecting the impregnated coating to an elevated temperature bake to cure the resin varish.
1 Assignment
0 Petitions
Accused Products
Abstract
A process for electrodepositing mica and a water soluble anionic resin binder, such as a modified polyester resin, is disclosed as a means for applying a heavy coating of a high-voltage, mica-bearing electrical insulation onto uninsulated and insulated portions of electrical connections in dynamoelectric machines. The electrodeposited mica coating is subsequently impregnated with a suitable resin, such as an epoxy or polyester resin, concurrently with the impregnation of other conventional insulations in the machine. Alternatively, deposition and impregnation of the connection insulation can be performed prior to installing the connection into the machine.
-
Citations
12 Claims
-
1. A process for depositing an insulating coating on bare portions of electrical connection members comprising the steps of
(a) immersing the bare electrical connections in an aqueous electrodeposition composition consisting essentially in weight percent of 5-35% of particulated mica, 0.2-2% of a water soluble anionic resin binder as calculated in resin solids, 0.001-0.20% of an electrolyte, up to 0.3% of a nonionic surfactant and a polar solvent; -
(b) electrodepositing said composition on the bare electrical connections and forming a dry micaceous coating of substantially uniform thickness, said coating being porous and containing a sufficient amount of binder to hold the mica particles together; (c) impregnating the porous coating with an impregnative resin varnish; and (d) subjecting the impregnated coating to an elevated temperature bake to cure the resin varish. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. The process for providing a continuous insulating covering on an electrical conductor which comprises the steps of:
-
a. wrapping a portion of the length of the conductor with insulating material; b. then immersing a bare unwrapped portion of the conductor and the adjacent wrapped portion thereof in an aqueous electrodeposition composition consisting essentially of 5-35% of particulated mica, 0.2-2% of a water soluble anionic resin binder as calculated in resin solids, 0.001-0.20% of an electrolyte, up to 0.3% of a non-ionic surfactant and a polar solvent; c. electrodepositing said composition on the bare unwrapped portion of the conductor and the adjacent wrapped portion and forming a continuous dry micaceous coating on the bare unwrapped and adjacent wrapped portions, said coating being porous and containing a sufficient amount of binder to hold mica particles together; d. impregnating the porous coating with an impregnative resin varnish; and
,e. subjecting the impregnated coating to an elevated temperature bake to cure the resin varnish. - View Dependent Claims (11)
-
-
12. In the process for insulating a multiple-coil stator of a dynamoelectric machine which includes the steps of wrapping the coils and portions of the coil leads with insulating tape and joining the coils in series by securing the respective coil leads together in pairs as coil connections, the combination of the steps of immersing the stator in an aqueous electrodeposition bath so that bare unwrapped portions and adjacent insulation-covered portions of the coil leads are submerged in the bath, and applying an anodic potential and thereby electrodepositing on both the bare portions and the adjacent wrapped portions of the coil leads a coating of substantially uniform thickness greater than about 50 mils, said aqueous bath consisting essentially of 5-35% of particulated mica, 0.2-2% of a water soluble polyester resin binder as calculated in resin solids, 0.001-0.20% of an electrolyte, up to 0.3% of a non-ionic surfactant and the remainder water.
Specification