Insulated armature coil for dynamoelectric machine
First Claim
1. For insulating an armature coil in a dynamoelectric machine having a rotor which comprises a commutator formed by a cylindrical array of discrete electroconductive segments at one end of the rotor, an armature head at the other end of the rotor, a cylindrical core of magnetizable material disposed between said commutator and armature head, said core including a plurality of axially extending slots in its periphery, a plurality of multiple turn armature coils physically disposed in the slots of said core and electrically connected to selected commutator segments, each armature coil comprising a bundle of parallel, separately insulated conductors the distal ends of which are adapted to be connected to a predetermined set of said commutator segments, each of said conductors having a generally rectangular cross section and said bundle being bent to form a generally rectilinear winding having first and second relatively long and straight slot sections that are adapted to be inserted in two separate slots of said rotor core, said first and second slot sections being respectively Joined at their armature head ends to first and second shorter sections which form obtuse angles therewith and which in turn extend convergently to the outboard end of the armature head where they join one another via an acutely bent loop, an improved insulating system comprising a first pre-formed tube of substantially non-compressible, non-thermoplastic dielectric material surrounding the exterior surface of essentially the whole of said first slot section and the exterior surface of at least part of said first shorter section of said coil, and a second pre-formed tube of the same material surrounding the exterior surface of essentially the whole of said second slot section and the exterior surface of at least part of said second shorter section of said coil, each of said tubes fitting snuggly but slidably over the exterior surface of the surrounded sections to provide electrical insulation between said bundle of conductors and the slot walls of said core, the wall of each tube having a unitary, seamless construction, being thin and flexible enough to bend in any plane without appreciable loss of either its physical or its dielectric integrity, and having a smooth enough interior surface to permit longitudinal expansion and contraction of said insulated conductors inside the tube.
1 Assignment
0 Petitions
Accused Products
Abstract
A multiple turn coil adapted to be inserted in a slot of a rotor in a dynamoelectric machine is formed by a bundle of individually insulated parallel bars of electroconductive material arranged close together and surrounded, in the vicinity of each slot section of the coil, by a pre-formed tube of substantially non-compressible, non-thermoplastic dielectric material (e.g., polyimide film), the wall of which is thin and flexible enough to bend in any plane and smooth enough to permit substantially unfettered longitudinal expansion and contraction of the insulated conductors inside the tube. Inside the coil a cross-shaped member of the same dielectric material enhances the turn-to-turn insulation.
48 Citations
18 Claims
- 1. For insulating an armature coil in a dynamoelectric machine having a rotor which comprises a commutator formed by a cylindrical array of discrete electroconductive segments at one end of the rotor, an armature head at the other end of the rotor, a cylindrical core of magnetizable material disposed between said commutator and armature head, said core including a plurality of axially extending slots in its periphery, a plurality of multiple turn armature coils physically disposed in the slots of said core and electrically connected to selected commutator segments, each armature coil comprising a bundle of parallel, separately insulated conductors the distal ends of which are adapted to be connected to a predetermined set of said commutator segments, each of said conductors having a generally rectangular cross section and said bundle being bent to form a generally rectilinear winding having first and second relatively long and straight slot sections that are adapted to be inserted in two separate slots of said rotor core, said first and second slot sections being respectively Joined at their armature head ends to first and second shorter sections which form obtuse angles therewith and which in turn extend convergently to the outboard end of the armature head where they join one another via an acutely bent loop, an improved insulating system comprising a first pre-formed tube of substantially non-compressible, non-thermoplastic dielectric material surrounding the exterior surface of essentially the whole of said first slot section and the exterior surface of at least part of said first shorter section of said coil, and a second pre-formed tube of the same material surrounding the exterior surface of essentially the whole of said second slot section and the exterior surface of at least part of said second shorter section of said coil, each of said tubes fitting snuggly but slidably over the exterior surface of the surrounded sections to provide electrical insulation between said bundle of conductors and the slot walls of said core, the wall of each tube having a unitary, seamless construction, being thin and flexible enough to bend in any plane without appreciable loss of either its physical or its dielectric integrity, and having a smooth enough interior surface to permit longitudinal expansion and contraction of said insulated conductors inside the tube.
- 14. For insulating an armature coil in a dynamoelectric machine having a rotor which comprises a commutator formed by a cylindrical array of discrete electroconductive segments at one end of the rotor, an armature head at the other end of the rotor, a cylindrical core of magnetizable material disposed between said commutator and armature head, said core including a plurality of axially extending slots in its periphery, and a plurality of multiple turn armature coils physically disposed in the slots of said core and electrically connected to selected commutator segments, each armature coil comprising a bundle of at least four parallel, separately insulated conductors arranged in quadrature with respect to each other, the distal ends of said conductors being adapted to be connected to a predetermined set of said commutator segments, each of said conductors having a generally rectangular cross section and said bundle being bent to form a generally rectilinear winding having first and second relatively long and straight slot sections that are adapted to be inserted in two separate slots of said rotor core, said first and second slot sections being surrounded by dielectric material and being respectively joined at their armature head ends to first and second shorter sections which form obtuse angles therewith and which in turn extend convergently to the outboard end of the armature head where they join one another via an acutely bent loop, an improved insulating system comprising insulating means disposed inside said bundle for separating said four conductors from one another at least in the vicinity of said obtuse angles and of said loop, said insulating means comprising a pre-formed unitary member of substantially non compressible, non-thermoplastic dielectric material having a cross-shaped cross section and being thin and flexible enough to bend in any plane without appreciable loss of either its physical integrity or its electrical insulating properties.
Specification