Patent US4868970A successfully refreshed from Google Patents.
US4868970A
Expired / Lapsed
US
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Method of making an electric motor
Assignee: Kollmorgen Corp
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Filing: 1987-03-19
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Granted: 1989-09-26
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Expires: 2007-03-19
Abstract
Abstract A method of making an electric motor with the stator winding inside a slotless cylindrical stator shell.
Inventors
- 👤 Roy D. Schultz
- 👤 Thomas R. England
- 👤 A. Clark Altizer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:41
CPC Classifications
H; H02; H02K; H02K15/00; H02K15/04; H02K15/043; H02K15/0432; H02K1/00; H02K1/06; H02K1/22; H02K1/27; H02K1/2706; H02K1/272; H02K1/274; H02K1/2753; H02K1/278; H02K15/06; H02K15/061; H02K3/00; H02K3/04; H02K3/46; H02K3/47; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49009
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
161 words
A method of making an electric motor with a stator winding having coil end turns at axial ends thereof inside a slotless cylindrical stator shell of magnetic material comprising the steps of: forming a slotless cylindrical stator shell of magnetic material; creating a generally cylindrical support with a reduced diameter portion at one end; forming the winding around said support from preformed coils such that the coiled end turns at one end of the stator winding are at the reduced diameter portion of said support and flare inwardly along said reduced diameter portion, and the coil end turns at the other end of the stator winding are at the other end of said support and flair outwardly; inserting said winding into said cylindrical stator shell starting with said inwardly flared end coils while the winding is supported by said support; removing said support from said winding; and impregnating said winding with a resin to secure said winding inside said stator shell.
Claim 2
Independent Claim
161 words
A method of making an electric motor with a stator winding having coil end turns at axial ends thereof inside a slotless cylindrical stator shell of magnetic material comprising the steps of: forming a slotless cylindrical stator shell of magnetic material; creating a generally cylindrical support with a reduced diameter portion at one end; forming the winding around said support from preformed coils such that the coiled end turns at one end of the stator winding are at the reduced diameter portion of said support and flare inwardly along said reduced diameter portion, and the coil end turns at the other end of the stator winding are at the other end of said support and flair outwardly; inserting said winding into said cylindrical stator shell starting with said inwardly flared end coils while the winding is supported by said support; removing said support from said winding; and impregnating said winding with a resin to secure said winding inside said stator shell.
Claim 3
Dependent Claim
20 words
The method according to claim 1 wherein said resin has a thermal conductivity in excess of 6 (BTU)(in)/(hr)(ft 2 )(°F.).
Claim 4
Dependent Claim
26 words
The method according to claim 1 wherein said resin has a coefficient of thermal expansion equal to or greater than that of the cylindrical stator shell.
Claim 5
Dependent Claim
19 words
The method according to claim 1 wherein said resin has a viscosity below 50,000 cps in the uncured state.
Claim 6
Dependent Claim
19 words
The method according to claim 1 wherein said resin is an epoxy filled with a non-conductive and non-magnetic ceramic.
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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) | 1992-09-25 | 1993-03-27 | 1993-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-25 | 1997-03-27 | 1997-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-25 | 2001-03-27 | 2001-09-26 | $7700.00 | Window Closed / Lapsed |