Salient field pole piece for dynamoelectric machines

Claim 2

In combination, a salient field pole piece for a dynamoelectric machine, comprising: a magnetic core member including a groove formed by diverging walls extending the surface of said magnetic core member and terminating in a bottom wall for supporting said salient field pole piece; a stack of laminations forming the body of said pole piece and carrying a field winding coil, said stack of laminations including a pole tip portion and a projection disposed oppositely to said pole tip portion and formed by diverging sides and a bottom side respectively complementary to said diverging walls and said bottom wall of said groove for mounting said stack of laminations to said magnetic core within an interlocking joint; a longitudinal slot having enclosed sides extending axially between the ends of said stack of laminations; a series of longitudinally spaced holes extending through said pole tip portion and said projection of said stack of laminations and communicating with the center of said longitudinal slot; a plurality of pins insertable in said series of longitudinally spaced holes and extending between said longitudinal slot and said bottom side of said projection and an elongated bar insertable in said longitudinal slot and extending between the ends of said stack of laminations, said elongated bar including a series of threaded openings coaxially aligned with each of said series of longitudinally spaced holes and carrying screw members engaging the ends of said plurality of pins, said screw members compressively loading said plurality of pins when said screw members are tightened in said threaded openings thereby clamping said plurality of pins against said bottom wall of said groove, whereby said diverging sides of said projeCtion are clamped against said diverging walls of said groove for high strength fastening of said salient field pole piece to said magnetic core member.

Claim 3

In combination, a salient field pole piece for a salient pole rotor of a dynamoelectric machine, comprising: a magnetic core member carried by the shaft of said dynamoelectric machine including a dovetail groove having diverging walls extending from the surface of said magnetic core member and terminating in a flat bottom wall for supporting said pole piece; a stack of laminations forming the body of said pole piece and carrying a field winding coil, said stack of laminations including an arcuate pole tip portion and a dovetail projection disposed oppositely to said pole tip portion and formed by diverging sides engaging said diverging walls of said dovetail groove and flat bottom side facing said flat bottom wall for mounting said laminated stack to said magnetic core along a mutually interlocking dovetail joint; a longitudinal slot having enclosed substantially rectangular sides extending axially between the ends of said pole tip portion of said stack of laminations; a series of longitudinally spaced holes extending through said pole tip portion and said dovetail projection and communicating with the center of said longitudinal slot, said longitudinally spaced holes including counterbored portions extending within said pole tip portion; a plurality of cylindrical pins slidingly fitting in said series of longitudinally spaced holes between said longitudinal slot and said bottom side of said dovetail projection; a rectangularly shaped elongated metal bar slidingly insertable in said longitudinal slot and extending between the ends of said stack of laminations and supported by said sides of said longitudinal slot, said elongated bar including a series of threaded openings coaxially aligned with each of said series of longitudinally spaced holes and having diameters larger than the diameters of said series of longitudinally spaced holes and less than the diameters of said counterbored portions; and a series of screws threadingly mounted in said threaded openings and compressively loading each of said plurality of cylindrical pins against said bottom wall of said dovetail groove whereby tightening of said series of screws presses said elongated bar against the outer side of said sides of said longitudinal slot and clamps said diverging sides of said dovetail projection against said diverging walls of said dovetail groove for securing said salient field pole piece in place on said magnetic core member.

Claim 4

In combination, a salient field pole piece for a salient pole rotor of a dynamoelectric machine, comprising: a magnetic core member carried by the shaft of said dynamoelectric machine including a dovetail groove having diverging walls extending from the surface of said magnetic core member and terminating in a flat bottom wall for supporting said pole piece; a stack of laminations forming the body of said pole piece and carrying a field winding coil, said stack of laminations including an arcuate pole tip portion and a dovetail projection disposed oppositely to said pole tip portion and formed by diverging sides engaging said diverging walls of said dovetail groove and flat bottom side facing said flat bottom wall for mounting said laminated stack to said magnetic core along a mutually interlocking dovetail joint; a longitudinal slot having enclosed substantially rectangular sides extending axially between the ends of said pole tip portion of said stack of laminations; a series of longitudinally spaced holes extending through said pole tip portion and said dovetail projection and communicating with the center of said longitudinal slot, said longitudinally spaced holes including counterbored portions extending within said pole tip portion; a plurality of cylindrical pins slidingly fitting in said series of longitudinally spaced holes between said longitudinal slot and said bottom side of said dovetail projection; a rectangularly shaped elongated metal bar slidingly insertable in said longitudinal slot and extending between the ends of said stack of laminations and supported by said sides of said longitudinal slot, said elongated bar including a series of threaded openings coaxially aligned with each of said series of longitudinally spaced holes and having diameters larger than the diameters of said series of longitudinally spaced holes and less than the diameters of said counterbored portions; and a series of screws threadingly mounted in said threaded openings and compressively loading each of said plurality of cylindrical pins against said bottom wall of said dovetail groove whereby tightening of said series of screws presses said elongated bar against the outer side of said sides of said longitudinal slot and clamps said diverging sides of said dovetail projection against said diverging walls of said dovetail groove for securing said salient field pole piece in place on said magnetic core member.