Patent US3209990A successfully refreshed from Google Patents.
US3209990A
Expired / Lapsed
US
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Two stage screw rotor machines
Assignee: Atlas Copco AB
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Filing: 1962-01-18
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Granted: 1965-10-05
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Expires: 1982-01-18
Abstract
No abstract record available.
Inventors
- 👤 Akerman Iwan Ernst Roland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:28
CPC Classifications
F; F04; F04C; F04C18/00; F04C18/08; F04C18/12; F04C18/14; F04C18/16; F04C23/00; F04C23/001; F04C27/00; F04C27/008; F04C27/009
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
168 words
IN A SCREW COMPRESSOR APPARATUS OF THE CHARACTER DESCRIBED HAVING A LOW PRESSURE STAGE AND A HIGH PRESSURE STAGE, THE COMBINATION WHICH COMPRISES A ONE-PIECE CYLINDRICAL CASING HAVING TWO OVERLAPPING PARALLEL BORES, AN END COVER FOR EACH END OF SAID CASING, A ONE-PIECE MALE ROTOR HAVING A LOW PRESSURE PORTION AND A HIGH PRESSURE PORTION WITH A SEALING PORTION THEREBETWEEN, A ONE-PIECE FEMALE ROTOR HAVING A LOW PRESSURE PORTION AND A HIGH PRESSURE PORTION WITH SEALING PORTION THEREBETWEEN, A PARTITION WALL SEPARABLE FROM SAID CASING FROM DIVIDING SAID LOW PRESSURE STAGE OF SAID CASING FROM HIGH PRESSURE STAGE PARTITION WALL HAVING THE OUTER PERIPHERY THEREOF IN SEALING ENGAGEMENT WITH SAID BORES IN SAID LOW PRESSURE STAGE OF SAID CASING, AND BEING DISPOSED ON SAID SELAING PORTIONS OF SAID ROTORS FOR SEALING FIT THEREON BETWEEN SAID LOW PRESSURE PORTION AND SAID HIGH PRESSURE PORTION THEREOF BEFORE SAID ROTORS ARE INSERTED IN SAID CASING, AND MEANS FOR HOLDING SAID PARTITION WALL AGAINST AXIAL DISPLACEMENT AFTER INSERTION THEREOF IN SAID CASING.
Claim 2
Dependent Claim
168 words
IN A SCREW COMPRESSOR APPARATUS OF THE CHARACTER DESCRIBED HAVING A LOW PRESSURE STAGE AND A HIGH PRESSURE STAGE, THE COMBINATION WHICH COMPRISES A ONE-PIECE CYLINDRICAL CASING HAVING TWO OVERLAPPING PARALLEL BORES, AN END COVER FOR EACH END OF SAID CASING, A ONE-PIECE MALE ROTOR HAVING A LOW PRESSURE PORTION AND A HIGH PRESSURE PORTION WITH A SEALING PORTION THEREBETWEEN, A ONE-PIECE FEMALE ROTOR HAVING A LOW PRESSURE PORTION AND A HIGH PRESSURE PORTION WITH SEALING PORTION THEREBETWEEN, A PARTITION WALL SEPARABLE FROM SAID CASING FROM DIVIDING SAID LOW PRESSURE STAGE OF SAID CASING FROM HIGH PRESSURE STAGE PARTITION WALL HAVING THE OUTER PERIPHERY THEREOF IN SEALING ENGAGEMENT WITH SAID BORES IN SAID LOW PRESSURE STAGE OF SAID CASING, AND BEING DISPOSED ON SAID SELAING PORTIONS OF SAID ROTORS FOR SEALING FIT THEREON BETWEEN SAID LOW PRESSURE PORTION AND SAID HIGH PRESSURE PORTION THEREOF BEFORE SAID ROTORS ARE INSERTED IN SAID CASING, AND MEANS FOR HOLDING SAID PARTITION WALL AGAINST AXIAL DISPLACEMENT AFTER INSERTION THEREOF IN SAID CASING.
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) | 1968-10-04 | 1969-04-05 | 1969-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-10-04 | 1973-04-05 | 1973-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-10-04 | 1977-04-05 | 1977-10-05 | $7700.00 | Window Closed / Lapsed |