US4901628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic actuator having a microwave antenna
Assignee: Motors Liquidation Co
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Filing: 1985-10-09
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Granted: 1990-02-20
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Expires: 2005-10-09
Abstract
Abstract A microwave method and apparatus for detecting the position of a piston of a pneumatic cylinder. While the piston is being moved by fluid pressure a microwave signal is applied to a cavity defined by the piston and interior of the cylinder and the reflected microwave signal is detected. The reflected microwave signal is processed to determine piston position.
Inventors
- 👤 Mark K. Krage
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:58
CPC Classifications
F; F15; F15B; F15B15/00; F15B15/20; F15B15/28; F15B15/2815; F15B15/2869; G; G01; G01R; G01R27/00; G01R27/02; G01R27/04; G05; G05D; G05D3/00; G05D3/12; G05D3/20; H; H01; H01P; H01P7/00; H01P7/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A hydraulic actuator having a microwave antenna comprising, a cylinder having an end cap, a piston reciprocable within said cylinder, a rod member extending axially of said piston that moves into an axially extending bore formed in said end cap when the piston has moved to a position engaging a portion of said end cap, passage means connecting the interior of the cylinder and the interior of said bore, an axially extending microwave antenna disposed within said bore and a recess formed in said rod member for receiving said antenna.
Claim 2
Dependent Claim
90 words
A hydraulic actuator having a microwave antenna comprising, a cylinder having an end cap, a piston reciprocable within said cylinder, a rod member extending axially of said piston that moves into an axially extending bore formed in said end cap when the piston has moved to a position engaging a portion of said end cap, passage means connecting the interior of the cylinder and the interior of said bore, an axially extending microwave antenna disposed within said bore and a recess formed in said rod member for receiving said antenna.
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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) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |