Electric rotating machine

Claim 2

An electric rotating machine comprising, in combination: a permanent magnet rotor having a plurality of rotor poles of alternate polarity; only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with magnetic flux, so that at a given moment said stator pole is of one polarity.

Claim 3

An electric rotating machine comprising, in combination: a permanent magnet rotor having a plurality of rotor poles of altPrnate alternate only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 4

An electric rotating machine comprising, in combination: a permanent magnet rotor having a plurality of rotor poles of altPrnate alternate only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 5

An electric rotating machine as defined in claim 2, in which the rotor comprises a plurality of axially spaced rotor sections which each have a plurality of rotor poles.

Claim 6

An electric rotating machine as defined in claim 3, which further comprises magnetic means for maintaining the rotor sections in axially spaced relationship.

Claim 7

An electric rotating machine comprising, in combination: a permanent magnet rotor having only a single pair of nonsalient rotor poles of alternate polarity; only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with magnetic flux, so that at a given moment said stator pole is of one polarity, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 8

An electric rotating machine comprising, in combination: a permanent magnet rotor having only a single pair of nonsalient rotor poles of alternate polarity; only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with magnetic flux, so that at a given moment said stator pole is of one polarity, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 9

A self-starting electric motor comprising, in combination: a permanent magnet rotor having a plurality of rotor poles of alternate polarity; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned parallel to the axis of rotation of the rotor such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles are disPlaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 10

A self-starting electric motor comprising, in combination: a permanent magnet rotor having a plurality of rotor poles of alternate polarity; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned parallel to the axis of rotation of the rotor such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles are disPlaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 11

A self-starting electric motor as defined in claim 6, in which the angle subtended by the stator pole with respect to the axis of rotation of the rotor is within the range of from about 90 electrical degrees to about 180 electrical degrees.

Claim 12

An electric rotating machine comprising, in combination: a permanent magnet rotor having nonsalient rotor poles, the ratio of the length to the diameter of the rotor being at least about 1.25 to 1; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near the rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 13

An electric rotating machine comprising, in combination: a permanent magnet rotor having nonsalient rotor poles, the ratio of the length to the diameter of the rotor being at least about 1.25 to 1; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near the rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 14

An electric rotating machine comprising, in combination: a permanent magnet rotor having a plurality of non-salient rotor poles of alternate polarity; a cylindrical stator structure coaxial with the rotor, the stator structure including a stator pole piece of magnetic material and only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with alternating magnetic flux, so that at a given moment said stator pole is of one polarity, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 15

An electric rotating machine comprising, in combination: a permanent magnet rotor having a plurality of non-salient rotor poles of alternate polarity; a cylindrical stator structure coaxial with the rotor, the stator structure including a stator pole piece of magnetic material and only a single salient stator pole in magnetic flux relationship with the rotor; and means for energizing the single salient stator pole with alternating magnetic flux, so that at a given moment said stator pole is of one polarity, the rotor being adapted consistently to assume a position with respect to the stator pole, when the machine is in a de-energized condition, in which the rotor poles are displaced from the center of the stator pole so that, when the machine is again energized, the rotor is self-starting.

Claim 16

An electric rotating machine as defined in claim 9, in which the stator pole piece is of cup-shaped configuration, and the single salient stator pole is integrally formed with the pole piece.

Claim 17

An electric rotating machine as defined in claim 9, in which the ratio of the length to the diameter of the rotor is at least about 1.25 to 1.

Claim 18

An electric rotating machine as defined in claim 9, in which the rotor is of ceramic material that has high magnetic coercivity, low permeability and low specific gravity, the rotor having a greater axial length than diameter.

Claim 19

A self-starting electric motor comprising, in combination: a permanent magnet rotor having two rotor pole pairs in axially spaced relationship with each other; only a single salient pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 20

A self-starting electric motor comprising, in combination: a permanent magnet rotor having two rotor pole pairs in axially spaced relationship with each other; only a single salient pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 21

A self-starting electric motor comprising, in combination: a permanent magnet rotor having nonsalient rotor pole pairs in axially spaced relationship with each other, the respective pairs having a fixed angular displacement with respect to one another which is less than 180 electrical degrees; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 22

A self-starting electric motor comprising, in combination: a permanent magnet rotor having nonsalient rotor pole pairs in axially spaced relationship with each other, the respective pairs having a fixed angular displacement with respect to one another which is less than 180 electrical degrees; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 23

A self-starting electric motor comprising, in combination: a permanent magnet rotor including two axially spaced rotor sections which each having only a single pair of nonsalient rotor poles, the rotor pole pairs in the respective sections having a fixed angular displacement with respect to one another; only a single salient stator pole in magnetic flux relationship with the rotor; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 24

A self-starting electric motor comprising, in combination: a permanent magnet rotor including two axially spaced rotor sections which each having only a single pair of nonsalient rotor poles, the rotor pole pairs in the respective sections having a fixed angular displacement with respect to one another; only a single salient stator pole in magnetic flux relationship with the rotor; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 25

A self-starting electric motor comprising, in combination: a rotor including two permanent magnet rotor sections and an intermediate section of magnetic material for maintaining the permanent magnet sections in axially spaced relationship with each other, each of the permanent magnet section having a pair of nonsalient rotor poles arranged such that the rotor poles in the respective sections have a fixed angular displacement with respect to one another which is less than 180 electrical degrees; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.

Claim 26

A self-starting electric motor comprising, in combination: a rotor including two permanent magnet rotor sections and an intermediate section of magnetic material for maintaining the permanent magnet sections in axially spaced relationship with each other, each of the permanent magnet section having a pair of nonsalient rotor poles arranged such that the rotor poles in the respective sections have a fixed angular displacement with respect to one another which is less than 180 electrical degrees; only a single salient stator pole in magnetic flux relationship with the rotor, the stator pole being positioned near each of the pairs of rotor poles such that the path of minimum reluctance through the stator pole when the rotor is in its quiescent position is one in which flux passes from a given rotor pole, circumferentially through the stator pole, and back to another rotor pole; and a field coil for energizing the single salient stator pole with alternating magnetic flux, the rotor being adapted consistently to assume a position with respect to the stator pole, when the field coil is de-energized, in which the rotor poles in at least one of said pairs are displaced from the center of the stator pole so that, when the field coil is again energized, the rotor is self-starting.