Closed slot rotor construction

Claim 2

A lamination for use in a lamination stack forming a rotor in a dynamo-electric machine, comprising: a flat circular plate of ferromagnetic material having a number of equally circumferentially spaced closed slots extending radially in a region near the outer periphery of said plate, said slots being formed to contain conducting members which extend axially along the rotor when like ones of said plates are stacked face-to-face with corresponding slots in communication with one another, each of said slots having an upper edge that is substantially in the shape of a V at an upper slot region adjacent the periphery of said plate and symmetrical about a radial center line, portions of said upper edge corresponding to legs of the V diverging from one another in the direction towards the center of said plate, and each upper edge portion corresponding to a leg of said V forms an angle of about 30 degrees with respect to a line drawn perpendicular to the radial center line of the slot; wherein said circular plate has bridge areas between said upper slot regions and the outer periphery of said plate, a center region of the upper edge of each slot is curved at a first radius between the edge portions corresponding to legs of said V to define a bridge area for each slot, and said slots are each formed to constrict toward the radial center line of the slot with opposing edges curved at a second radius between distal ends of the upper edge and a first set of points along which the opposing edges have a common tangent which is perpendicular to said radial center line; wherein the center region of the upper edge of each slot forms a narrowest part of each bridge area, and the radial dimension of said narrowest part is in the range from about 0.25 mm to about 0.4 mm.

Claim 3

A lamination according to claim 1, wherein opposing edges of said slots are curved continuously at a third radius to constrict toward said center line from said common tangent line and radially inward over an arc of 90 degrees to a second set of points defining tops of neck portions of said slots.

Claim 4

A lamination according to claim 2, wherein the tops of said neck portions are located at points radially of said plate such as to optimize electromagnetic performance.

Claim 5

A lamination according to claim 2, wherein said first radius is about 0.932 mm., said second radius is about 0.813 mm., and said third radius is about 0.7 mm.

Claim 6

A lamination according to claim 2, wherein said first radius is about 0.892 mm., said second radius is about 0.919 mm., and said third radius is about 0.76 mm.

Claim 7

A lamination according to claim 2, wherein said first radius is about 0.933 mm., said second radius is about 0.715 mm., and said third radius is about 0.76 mm.

Claim 8

A lamination according to claim 2, wherein said first radius is about 0.934 mm., said second radius is about 1.105 mm., and said third radius is about 0.762 mm.

Claim 9

A lamination according to claim 3, wherein said plate has a diameter of about 95 mm. and the tops of said neck portions are located at a radius of about 43.462 mm.

Claim 10

A lamination according to claim 3, wherein said plate has a diameter of about 122 mm. and the tops of said neck portions are located at a radius of about 56.9 mm.

Claim 11

A lamination according to claim 3, wherein said plate has a diameter of about 150 mm. and the tops of said neck portions are located at a radius of about 70 mm.

Claim 12

A dynamo-electric machine, comprising: a generally cylindrical casing; a stator fixed in said casing and comprised of a stack of plate laminations of ferromagnetic material, said stator having a cylindrical bore; a stator winding embedded in stator slots which extend radially outward from the circumference of said bore; a rotor comprised of a stack of rotor laminations of ferromagnetic material and supported by said casing in said bore for rotational movement about the bore axis, said rotor including conductive means for interacting with a magnetic field when said stator windings are energized by an outside electrical source; wherein each of the rotor laminations comprises: a flat circular plate of ferromagnetic material having a number of equally circumferentially spaced closed slots extending radially in a region near the outer periphery of said plate, said slots being formed to contain conducting members which extend axially along the rotor when like ones of said plates are stacked face-to-face with corresponding slots substantially aligned with one another, each of said slots having an upper edge that is substantially in the shape of a V at an upper slot region adjacent the periphery of said plate and symmetrical about a radial center line, portions of said upper edge corresponding to legs of the V diverging from one another in the direction towards the center of said plate, and each upper edge portion corresponding to a leg of said V forms an angle of about 30 degrees with respect to a line drawn perpendicular to the radial center line of the slot; wherein said circular plate has bridge areas between said upper slot regions and the outer periphery of said plate, a center region of the upper edge of each slot is curved at a first radius between the edge portions corresponding to legs of said V to define a bridge area for each slot, and said slots are each formed to constrict toward the radial center line of the slot with opposing edges curved at a second radius between distal ends of the upper edge and a first set of points along which the opposing edges have a common tangent which is perpendicular to said radial center line; wherein the center region of the upper periphery of each slot forms a narrowest part of each bridge area, and the radial dimension of said narrowest part is in the range from about 0.25 mm to about 0.4 mm.

Claim 13

A dynamo-electric machine, comprising: a generally cylindrical casing; a stator fixed in said casing and comprised of a stack of plate laminations of ferromagnetic material, said stator having a cylindrical bore; a stator winding embedded in stator slots which extend radially outward from the circumference of said bore; a rotor comprised of a stack of rotor laminations of ferromagnetic material and supported by said casing in said bore for rotational movement about the bore axis, said rotor including conductive means for interacting with a magnetic field when said stator windings are energized by an outside electrical source; wherein each of the rotor laminations comprises: a flat circular plate of ferromagnetic material having a number of equally circumferentially spaced closed slots extending radially in a region near the outer periphery of said plate, said slots being formed to contain conducting members which extend axially along the rotor when like ones of said plates are stacked face-to-face with corresponding slots substantially aligned with one another, each of said slots having an upper edge that is substantially in the shape of a V at an upper slot region adjacent the periphery of said plate and symmetrical about a radial center line, portions of said upper edge corresponding to legs of the V diverging from one another in the direction towards the center of said plate, and each upper edge portion corresponding to a leg of said V forms an angle of about 30 degrees with respect to a line drawn perpendicular to the radial center line of the slot; wherein said circular plate has bridge areas between said upper slot regions and the outer periphery of said plate, a center region of the upper edge of each slot is curved at a first radius between the edge portions corresponding to legs of said V to define a bridge area for each slot, and said slots are each formed to constrict toward the radial center line of the slot with opposing edges curved at a second radius between distal ends of the upper edge and a first set of points along which the opposing edges have a common tangent which is perpendicular to said radial center line; wherein the center region of the upper periphery of each slot forms a narrowest part of each bridge area, and the radial dimension of said narrowest part is in the range from about 0.25 mm to about 0.4 mm.

Claim 14

A machine according to claim 11, wherein opposing edges of said slots are curved continuously at a third radius to constrict toward said center line from said common tangent and radially inward over an arc of 90 degrees to a second set of points defining tops of neck portions of said slots.

Claim 15

A machine according to claim 12, wherein the tops of said neck portions are located at points radially of said plate such as to optimize electromagnetic performance.

Claim 16

A machine according to claim 12, wherein said first radius is about 0.932 mm., said second radius is about 0.813 mm., and said third radius is about 0.7 mm.

Claim 17

A machine according to claim 12, wherein said first radius is about 0.892 mm., said second radius is about 0.919 mm., and said third radius is about 0.76 mm.

Claim 18

A machine according to claim 12, wherein said first radius is about 0.933 mm., said second radius is about 0.715 mm., and said third radius is about 0.76 mm.

Claim 19

A machine according to claim 12, wherein said first radius is about 0.934 mm., said second radius is about 1.105 mm., and said third radius is about 0.762 mm.

Claim 20

A machine according to claim 13, wherein said plate has a diameter of about 95 mm. and the tops of said neck portions are located at a radius of about 43.462 mm.

Claim 21

A machine according to claim 13, wherein said plate has a diameter of about 122 mm. and the tops of said neck portions are located at a radius of about 56.9 mm.

Claim 22

A machine according to claim 13, wherein said plate has a diameter of about 150 mm. and the tops of said neck portions are located at a radius of about 70 mm.