US3558248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screw type refrigerant compressor
Assignee: Lennox Industries Inc
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Filing: 1968-01-10
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Granted: 1971-01-26
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Expires: 1988-01-10
Abstract
Abstract A REFRIGERANT SCREW COMPRESSOR INCORPORATING VALVE MEANS CONSTRUCTED AND ARRANGED TO ROTATE WITH THE SCREWS TOT PROVIDE A VARIABLE COMPRESSION RATIO RESPONSIVE TO CONDITIONS OF THE REFRIGERATION SYSTEM IN WHICH THE COMPRESSOR IS USED. THE SCREWS MAY BE PROVIDED WITH A PRESELECTED VARIABLE SKEW FOR MAINTAINING ADEQUATE FLUID FLOW THROUGH THE VALVE MEANS WITH A MINIMUM PRESSURE DROP. LUBRICANT IS SUPPLIED TO THE WORKING SPACE WITHIN WHICH THE SCREWS OPERATE FROM A SUMP WITHIN THE COMPRESSOR CASING BY PUMP MEANS WITHIN THE SCREWS FOR INCREASING SCREW COMPRESSION PERFORMANCE.
Inventors
- 👤 Sidney A Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:10
CPC Classifications
F; F04; F04C; F04C29/00; F04C29/12; F04C29/124; F04C29/126; F04C29/128; F04C18/00; F04C18/08; F04C18/12; F04C18/14; F04C18/16; F25; F25B; F25B1/00; F25B1/04; F25B1/047
Claims Analysis
Total Claims: 0
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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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |