Patent US3777191A successfully refreshed from Google Patents.
US3777191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dynamo electric machine construction
Assignee: Ebm Papst St Georgen GmbH and Co KG
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Filing: 1971-12-23
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Granted: 1973-12-04
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Expires: 1991-12-23
Abstract
Abstract The rotor of a dynamo electric machine, one which is to be supported only at one end, is attached to the shaft by a diskshaped steel element of circular outline which has outer marginal portions which are cast into the conductor portions of a squirrel cage rotor, the casting being, of aluminum for light weight and high conductivity; in a preferred form, the disk-shaped steel element is dished or bowed, and the marginal portions are bentover, in contact with the magnetic elements of the rotor, or spaced therefrom by a distance sufficient to leave enough casting material adjacent the motor so that the resistivity of the shortcircuited squirrel cage windings will be hardly increased by the presence of the steel element.
Inventors
- 👤 G Papst
- 👤 G Wrobel
- 👤 G Schneider
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:22
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/22; H02K1/28
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
173 words
External rotor dynamo electric machine having a support, a central stator fixed in the support, a shaft, an external rotor rotatable with the shaft with respect to the stator about the axis of the shaft, said rotor surrounding the stator and having a magnetic circuit, axially extending conductor portions and short circuit rings located at the ends of the axially extending conductors, the short circuit rings comprising good electrically conductive metal integrally connected to the axially extending portions and forming therewith an external squirrel cage rotor; and means securing the external squirrel cage rotor and the shaft for joint rotation together at one end portion of the rotor, said means comprising a disk-shaped sheet metal element of structurally strong material and of essentially circular outline extending diametrically of the motor, said element being centrally secured to the shaft and having outer marginal portions formed with projecting portions the projecting portions extending in axial direction and being cast into and integrally secured within one of the electrically conductive short circuit rings of the rotor.
Claim 2
Dependent Claim
173 words
External rotor dynamo electric machine having a support, a central stator fixed in the support, a shaft, an external rotor rotatable with the shaft with respect to the stator about the axis of the shaft, said rotor surrounding the stator and having a magnetic circuit, axially extending conductor portions and short circuit rings located at the ends of the axially extending conductors, the short circuit rings comprising good electrically conductive metal integrally connected to the axially extending portions and forming therewith an external squirrel cage rotor; and means securing the external squirrel cage rotor and the shaft for joint rotation together at one end portion of the rotor, said means comprising a disk-shaped sheet metal element of structurally strong material and of essentially circular outline extending diametrically of the motor, said element being centrally secured to the shaft and having outer marginal portions formed with projecting portions the projecting portions extending in axial direction and being cast into and integrally secured within one of the electrically conductive short circuit rings of the rotor.
Claim 3
Dependent Claim
12 words
Machine according to claim 1, wherein the disK-shaped element is concavely bowed.
Claim 4
Dependent Claim
15 words
Machine according to claim 1, wherein the disk-shaped element is a punched sheet metal disk.
Claim 5
Dependent Claim
44 words
Machine according to claim 1, wherein the outer marginal portions of the sheet metal element are formed with radial cut-outs, the remaining metal of the outer marginal portions forming projecting ribs, said ribs being cast into the adjacent short circuit ring of the rotor.
Claim 6
Dependent Claim
21 words
Machine according to claim 4, wherein the ribs are, in plan view, essentially T-shaped, and are formed with circumferentially extending bulges.
Claim 7
Dependent Claim
30 words
Machine according to claim 1, wherein the short circuit rings comprise high conductivity aluminum and the projecting portions are ribs cast into the adjacent short circuit ring of the rotor.
Claim 8
Dependent Claim
74 words
Machine according to claim 1, wherein the axially extending marginal portions form projecting ribs which are speced from the magnetic circuit of the rotor by a distance (h) determined by the current flow in the short circuit rings, said distance (h) being selected to introduce additional resistance into the short circuit rings which is small with respect to the resistance of the rings without the marginal portions to minimize power loss of the machine.
Claim 9
Dependent Claim
42 words
Machine according to claim 1, wherein the marginal portions of the disk-shaped elements are mechanically connected with the magnetic circuit of the rotor and form a portion of the rotor stack and are secured thereto by the conductor material of the rotor.
Claim 10
Dependent Claim
19 words
Machine according to claim 1, wherein the disk-shaped element has axially extending end portions to form a cup-shaped element.
Claim 11
Dependent Claim
22 words
Machine according to claim 1, wherein the disk-shaped element has a central cylindrical projection, the central projection being connected with the shaft.
Claim 12
Dependent Claim
54 words
Machine according to claim 1, wherein the disk-shaped element has a central opening which has portions which are non-circular; a bushing pressed into the central opening and being deformed such that the material of the bushing flows in the non-circular portions to form a non-rotatable connection between the bushing and the sheet metal element.
Claim 13
Dependent Claim
30 words
Machine according to claim 1, wherein the sheet metal element has a central opening; a bushing secured in the central opening, the bushing being welded to the sheet metal element.
Claim 14
Dependent Claim
31 words
Machine according to claim 1, wherein the sheet metal element is formed with a central opening; a bushing inserted into the central opening, the bushing being brazed to the central opening.
Claim 15
Dependent Claim
45 words
Machine according to claim 1, wherein the sheet metal element is a precision punched part having a central opening punched therein, the central opening being held to accurate tolerance throughout the thickness of the sheet metal element; the shaft being press-fitted into said central opening.
Claim 16
Dependent Claim
46 words
Machine according to claim 1, wherein the sheet metal element is formed, along its face, with projecting fins punched from the plane of the sheet metal element to provide openings through the sheet metal element and air scoops for ventilation of the interior of the rotor.
Claim 17
Dependent Claim
43 words
Machine according to claim 16, wherein the punched fins are located on concentric circles of the sheet metal element, selected fins projecting in opposite directions to provide air scoops for the interior of the motor regardless of direction of rotation of the rotor.
Claim 18
Dependent Claim
29 words
Machine according to claim 1, wherein the sheet metal element is deformed by circumferential shallow rings extending concentrically with the shaft into the plane of the sheet metal element.
Claim 19
Dependent Claim
14 words
Motor according to claim 1, wherein the disk-shaped sheet metal element is of steel.
Claim 20
Dependent Claim
177 words
Fractional horse power motor having a shaft, a stator surrounding the shaft windings surrounding the stator, and an external squirrel cage rotor surrounding the stator and having an electromagnetic portion comprising axial conductor bars and integrally connected short circuit end rings comprising a material of good electrical conductivity but of Low mechanical strength, and stacks of magnetic laminations being cast between the short circuit end rings; and a sheet metal disk of a material of high mechanical strength and an electrical conductivity which is low with respect to that of the conductor end rings and bars, formed with a central opening, the shaft being secured to the central opening, transversely of the disk with an interference fit to locate the disk adjacent an end portion of the stator; the sheet metal disk having axially extending projecting marginal portions which are cast into and integrally secured into the adjacent short circuit end ring to secure the electromagnetic portion of the rotor directly to the shaft and form a unitary, integral rotor-shaft assembly which can rotate about the stator.
Claim 21
Dependent Claim
177 words
Fractional horse power motor having a shaft, a stator surrounding the shaft windings surrounding the stator, and an external squirrel cage rotor surrounding the stator and having an electromagnetic portion comprising axial conductor bars and integrally connected short circuit end rings comprising a material of good electrical conductivity but of Low mechanical strength, and stacks of magnetic laminations being cast between the short circuit end rings; and a sheet metal disk of a material of high mechanical strength and an electrical conductivity which is low with respect to that of the conductor end rings and bars, formed with a central opening, the shaft being secured to the central opening, transversely of the disk with an interference fit to locate the disk adjacent an end portion of the stator; the sheet metal disk having axially extending projecting marginal portions which are cast into and integrally secured into the adjacent short circuit end ring to secure the electromagnetic portion of the rotor directly to the shaft and form a unitary, integral rotor-shaft assembly which can rotate about the stator.
Claim 22
Dependent Claim
14 words
Motor according to claim 19, wherein the end rings and conductor bars are aluminum.
Claim 23
Dependent Claim
12 words
Motor according to claim 19, wherein the sheet metal disk is steel.
Claim 24
Dependent Claim
31 words
Motor according to claim 19, wherein the marginal portions of the sheet metal disk are perforated and the regions of marginal portions beyond the perforations are cast into the rotor-shaft assembly.
Claim 25
Dependent Claim
43 words
Motor according to claim 19, wherein the central opening of the shaft, at least in part, is noncircular; a bushing press-fitted into the opening and having bushing material flowed into the non-circular portions of the opening; the bushing being secured to said shaft.
Claim 26
Dependent Claim
40 words
Machine according to claim 9, wherein the outer marginal portions of the disk-shaped sheet metal element comprise radially extending end portions joined to the axially extending portions, the radially extending portions being connected with the magnetic circuit of the rotor.
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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) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |