US3596121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric induction motor
Assignee: Robbins and Myers Inc
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Filing: 1969-09-10
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Granted: 1971-07-27
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Expires: 1989-09-10
Abstract
Abstract An induction motor capable of being operated single phase, polyphase, capacitor run, shaded pole, etc., having an inner wound member constituting a primary and an outer squirrel cage member. Either the inner or outer member may be the stator. The outer member is provided with a supporting member of magnetic material which not only gives mechanical support to the outer member but also serves as a substantial part of the return magnetic path making it possible to reduce the depths below slot of the outer member drastically, and the eddy current and hysteresis loss of the supporting member add to the induced currents in the squirrel cage to produce additional induction motor torque so that the physical size of the squirrel cage can be substantially reduced.
Inventors
- 👤 Sheldon S L Chang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:42
CPC Classifications
H; H02; H02K; H02K17/00; H02K17/02; H02K17/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
189 words
An induction motor comprising: an inner member of laminated steel constituting a primary, said inner member having a set of windings arranged to provide an even number of poles; an outer member of laminated steel constituting a secondary, said outer member having slots containing a squirrel cage winding facing said windings of said inner member, the depth of laminated steel below said slot in said outer member being substantially less than the tooth width between said slots multiplied by the number of slots and divided by three times the number of said poles; a supporting member of magnetic material rigidly attached to said outer member and having a rotating bearing support with respect to said inner member, said supporting member constituting an essential part in completing the magnetic path for the alternating flux; and means for energizing the windings of said inner member with alternating current to produce an alternating magnetic flux linking said squirrel cage winding with said windings of said inner member, whereby said depth of laminated steel is too small to carry all the flux and forces a majority of said flux into said supporting member.
Claim 2
Dependent Claim
189 words
An induction motor comprising: an inner member of laminated steel constituting a primary, said inner member having a set of windings arranged to provide an even number of poles; an outer member of laminated steel constituting a secondary, said outer member having slots containing a squirrel cage winding facing said windings of said inner member, the depth of laminated steel below said slot in said outer member being substantially less than the tooth width between said slots multiplied by the number of slots and divided by three times the number of said poles; a supporting member of magnetic material rigidly attached to said outer member and having a rotating bearing support with respect to said inner member, said supporting member constituting an essential part in completing the magnetic path for the alternating flux; and means for energizing the windings of said inner member with alternating current to produce an alternating magnetic flux linking said squirrel cage winding with said windings of said inner member, whereby said depth of laminated steel is too small to carry all the flux and forces a majority of said flux into said supporting member.
Claim 3
Dependent Claim
29 words
An induction motor according to claim 1, in which the depth below the slots of said outer member is approximately equal to the tooth width of said outer member.
Claim 4
Dependent Claim
38 words
An induction motor according to claim 1, wherein said inner member is fixedly mounted to constitute a stator, and said outer member and said supporting member together constitute a rotor, rotating freely and concentrically about said inner member.
Claim 5
Dependent Claim
55 words
An induction motor according to claim 1, wherein said supporting member completely encloses both said outer and inner members and constitutes a stationary motor frame, and said inner member is free to rotate concentrically within said outer member, and wherein slipring means are provided to energize the windings of said inner member while it rotates.
Claim 6
Dependent Claim
24 words
An induction motor according to claim 1, wherein a disc of highly conductive material is secured to the interior side of said supporting member.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |