US4712028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetically assisted stepping motor
Assignee: Sigma Instruments Inc
•
Filing: 1984-05-21
•
Granted: 1987-12-08
•
Expires: 2004-05-21
Abstract
Abstract A stepping motor with toothed stator poles and toothed rotor poles is magnetically enhanced by locating permanently magnetized inserts in the spaces between the stator teeth and magnetizing the inserts transverse to the direction of movement of the rotor and substantially transverse to the direction in which the teeth extend. In a hybrid motor with a split and axially magnetized rotor the inserts are magnetized to oppose the magnetization of the rotor. In a variable reluctance motor with an unmagnetized rotor inserts are placed in both rotor and stator and magnetized to aid each other. Linear motors use either configuration.
Inventors
- 👤 Ralph W. Horber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:49
CPC Classifications
H; H02; H02K; H02K37/00; H02K37/10; H02K37/20; H02K37/12; H02K37/14; H02K37/18; H02K41/00; H02K41/02; H02K41/03
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
179 words
A stepping motor, comprising: a stator a plurality of poles on said stator, a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the stator teeth; said rotor teeth being skewed relative to the transverse direction of the path of movement by a fraction of a tooth pitch; said permanently magnetized insert including a neodymium-boron alloy.
Claim 2
Dependent Claim
179 words
A stepping motor, comprising: a stator a plurality of poles on said stator, a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the stator teeth; said rotor teeth being skewed relative to the transverse direction of the path of movement by a fraction of a tooth pitch; said permanently magnetized insert including a neodymium-boron alloy.
Claim 3
Dependent Claim
211 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor being arranged to rotate about an axis relative to said stator; said rotor teeth being divided into two axially extending sets axially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into two portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 4
Dependent Claim
211 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor being arranged to rotate about an axis relative to said stator; said rotor teeth being divided into two axially extending sets axially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into two portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 5
Dependent Claim
54 words
A motor as in claim 2, wherein a plurality of said inserts are adjacent said stator teeth facing a set of rotor teeth and include respective magnetic poles; the magnetic pole on each of said inserts facing set of magnetized rotor teeth is poled to oppose the set of rotor teeth facing the insert.
Claim 6
Dependent Claim
207 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said inserts being located in spaces adjacent the stator teeth; said rotor teeth being divided into two axially extending sets axially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 7
Dependent Claim
207 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said inserts being located in spaces adjacent the stator teeth; said rotor teeth being divided into two axially extending sets axially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 8
Dependent Claim
215 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor teeth extending substantially transverse to the path of movement and the direction of the depth; said rotor teeth being divided into two axially extending sets radially displaced from each other, said sets being magnetized in opposite direction, said stator teeth being divided into two portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 9
Dependent Claim
215 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a winding on each of said poles; a plurality of spaced stator teeth on each of said poles, each of said poles having at least one tooth; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized inserts located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor teeth extending substantially transverse to the path of movement and the direction of the depth; said rotor teeth being divided into two axially extending sets radially displaced from each other, said sets being magnetized in opposite direction, said stator teeth being divided into two portions each opposing one of the sets; the inserts in one of said portions or sets being magnetized along the depth in one direction and the inserts in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 10
Dependent Claim
197 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the stator teeth; a plurality of said inserts being adjacent said stator teeth facing a set of rotor teeth and including respective magnetic poles; the magnetic pole on each of said structures facing a set of magnetized rotor teeth being poled to oppose the set of rotor teeth facing the insert.
Claim 11
Dependent Claim
197 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the stator teeth; a plurality of said inserts being adjacent said stator teeth facing a set of rotor teeth and including respective magnetic poles; the magnetic pole on each of said structures facing a set of magnetized rotor teeth being poled to oppose the set of rotor teeth facing the insert.
Claim 12
Dependent Claim
197 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the rotor teeth; a plurality of said inserts being adjacent said stator teeth facing a set of rotor teeth and including respective magnetic poles; the magnetic pole on each of said structures facing a set of magnetized rotor teeth being poled to oppose the set of rotor teeth facing the insert.
Claim 13
Dependent Claim
197 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said structures being located in spaces adjacent the rotor teeth; a plurality of said inserts being adjacent said stator teeth facing a set of rotor teeth and including respective magnetic poles; the magnetic pole on each of said structures facing a set of magnetized rotor teeth being poled to oppose the set of rotor teeth facing the insert.
Claim 14
Dependent Claim
172 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along the direction of movement and depths transverse to the direction of movement; a permanently magnetized material in each of the spaces between the teeth on one of the rotor and the stator; and said magnetized material being poled in the direction of the depth of the spaces; said rotor teeth and said stator teeth each having faces substantially transverse to the path of movement, said magnetized material in each of said spaces being in contact with a face.
Claim 15
Dependent Claim
172 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along the direction of movement and depths transverse to the direction of movement; a permanently magnetized material in each of the spaces between the teeth on one of the rotor and the stator; and said magnetized material being poled in the direction of the depth of the spaces; said rotor teeth and said stator teeth each having faces substantially transverse to the path of movement, said magnetized material in each of said spaces being in contact with a face.
Claim 16
Dependent Claim
223 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor rotates about an axis relative to said stator; said rotor teeth being divided into two axially extending sets axially and circumferentially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into portions each opposing one of the sets, the structures in one of said portions or sets being magnetized along the depth in one direction and the structures in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 17
Dependent Claim
223 words
A stepping motor, comprising: a stator a plurality of poles on said stator; a plurality of spaced stator teeth on each of said poles; winding means for energizing each of said poles so as to magnetize the plurality of teeth on any one of said poles in the same direction at any one time; a rotor movable relative to said stator; said rotor having a plurality of spaced rotor teeth located for movement along a first direction past said stator pole teeth; said rotor teeth and said stator teeth forming spaces having widths along a path of relative rotor-stator movement and depths transverse to the path of movement; a plurality of permanently magnetized structures located adjacent to the plurality of rotor teeth or the plurality of stator teeth and poled in the direction of the depth of the spaces; said rotor rotates about an axis relative to said stator; said rotor teeth being divided into two axially extending sets axially and circumferentially displaced from each other, said sets being magnetized in opposite directions, said stator teeth being divided into portions each opposing one of the sets, the structures in one of said portions or sets being magnetized along the depth in one direction and the structures in the other of said portions or sets being magnetized along the depth in the opposite direction.
Claim 18
Dependent Claim
35 words
A motor as in claim 2, wherein the magnetic poles on each of said inserts facing a set of magnetized rotor teeth is poled the opposite as the set of rotor teeth facing the insert.
Claim 19
Dependent Claim
28 words
A motor as in claim 2, wherein said rotor teeth are skewed relative to the transverse direction of the path of movement by fraction of a tooth pitch.
Claim 20
Dependent Claim
14 words
A motor as in claim 2, wherein said permanently magnetized insert includes samarium cobalt.
Claim 21
Dependent Claim
15 words
A motor as in claim 2, wherein said permanently magnetized insert includes a neodymium-boron alloy.
Claim 22
Dependent Claim
23 words
A motor as in claim 2, wherein said rotor teeth extend transverse to the path of movement and the direction of the depth.
Claim 23
Dependent Claim
29 words
A motor as in claim 2, wherein said rotor teeth are skewed relative to the transverse direction of the path of movement by a fraction of a tooth pitch.
Claim 24
Dependent Claim
13 words
A motor as in claim 14, wherein said magnetized insert includes samarium cobalt.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-12-07 | 1991-06-08 | 1991-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-07 | 1995-06-08 | 1995-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-07 | 1999-06-08 | 1999-12-08 | $7700.00 | Window Closed / Lapsed |