Patent US3973448A successfully refreshed from Google Patents.
US3973448A
Expired / Lapsed
US
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Electric hoists
Assignee: Individual
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Filing: 1973-05-09
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Granted: 1976-08-10
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Expires: 1993-05-09
Abstract
Abstract This invention relates in general to certain new and useful improvements in electric hoists. Presently produced hoists do not use electric drills for power and are relatively large, heavy and costly.
Inventors
- 👤 Edwin R. Michelsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:37
CPC Classifications
B; B66; B66D; B66D3/00; B66D3/18; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19023; Y10T74/19051; Y10T74/19056; Y10T74/19642; Y10T74/19647; Y10T74/19679
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
65 words
In combination with (1) through (51) one or more protruding shafts (17), (18). (19) and (20) supporting reversing electric drills attached by means of geared chucks, with such drills being prevented from turning by a drill-connecting cross (44) or case mounted fixture (50) and with any and all electric drills receiving the same electric impulse command from one switch; a method of achieving lifting force.
Claim 2
Dependent Claim
65 words
In combination with (1) through (51) one or more protruding shafts (17), (18). (19) and (20) supporting reversing electric drills attached by means of geared chucks, with such drills being prevented from turning by a drill-connecting cross (44) or case mounted fixture (50) and with any and all electric drills receiving the same electric impulse command from one switch; a method of achieving lifting force.
Claim 3
Dependent Claim
53 words
A device according to claim 1 whereon the protruding shafts (17), (18), (19) and (20) have small, flat areas milled on one side to provide seating for set screws of hand cranks with such hand cranks providing a means of applying lifting torque to the protruding shafts where electrical power is not available.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-10 | 1980-02-09 | 1980-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-10 | 1984-02-09 | 1984-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-10 | 1988-02-09 | 1988-08-10 | $7700.00 | Window Closed / Lapsed |