US3858484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic, rotary servo-actuator
Assignee: Mitsubishi Metal Corp
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Filing: 1973-10-18
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Granted: 1975-01-07
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Expires: 1993-10-18
Abstract
Abstract A hydraulic, rotary servo-actuator of the type having a casing, a first control valve, an input shaft provided therewithin with hydraulic fluid supply and discharge passageways, and a hydraulically actuated member further has other hydraulic fluid supply and discharge passageways formed within its casing and respectively communicating with a fluid supply source and a fluid reservoir both outside the servo-actuator and a second control valve formed within the casing and operating to communicate and shut off selectively these other passageways respectively with and from the passageways formed within the input shaft thereby to prevent excessive actuated movement of the hydraulically actuated member.
Inventors
- 👤 Youichi Saida
- 👤 Hajime Ito
- 👤 Kojiro Imanaga
- 👤 Tomoji Jyumonji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:39
CPC Classifications
F; F15; F15B; F15B9/00; F15B9/02; F15B9/08; F15B9/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
196 words
A hydraulic, rotary servo-actuator comprising: a closed cylindrical enclosure having therewithin a plurality of hydraulic action chambers; an input shaft entering said enclosure one end thereof and rotatably and coaxially supported therewithin; an actuated member comprising a part having a central axial bore, into which said input shaft is rotatably fitted, a rotor part provided with hydraulically actuated parts movably disposed within said chambers, and an output shaft connected unitarily to said rotor part; a first control valve provided in said input shaft and central axial bore and operating to communicate the chambers selectively with hydraulic fluid supply and discharge passageways formed within the input shaft; other hydraulic fluid supply and discharge passageways formed within a wall of the enclosure and respectively communicating with a hydraulic fluid supply source and a hydraulic fluid reservoir both outside of the servo-actuator; and a second control valve provided within the input shaft and central axial bore and operating interrelatedly with said first control valve to communicate and shut off selectively said other supply and discharge passageways respectively with and from the aforesaid passageways formed within the input shaft thereby to prevent excessive actuated movement of said hydraulically actuated parts.
Claim 2
Dependent Claim
196 words
A hydraulic, rotary servo-actuator comprising: a closed cylindrical enclosure having therewithin a plurality of hydraulic action chambers; an input shaft entering said enclosure one end thereof and rotatably and coaxially supported therewithin; an actuated member comprising a part having a central axial bore, into which said input shaft is rotatably fitted, a rotor part provided with hydraulically actuated parts movably disposed within said chambers, and an output shaft connected unitarily to said rotor part; a first control valve provided in said input shaft and central axial bore and operating to communicate the chambers selectively with hydraulic fluid supply and discharge passageways formed within the input shaft; other hydraulic fluid supply and discharge passageways formed within a wall of the enclosure and respectively communicating with a hydraulic fluid supply source and a hydraulic fluid reservoir both outside of the servo-actuator; and a second control valve provided within the input shaft and central axial bore and operating interrelatedly with said first control valve to communicate and shut off selectively said other supply and discharge passageways respectively with and from the aforesaid passageways formed within the input shaft thereby to prevent excessive actuated movement of said hydraulically actuated parts.
Claim 3
Dependent Claim
107 words
A hydraulic, rotary servo-actuator as set forth in claim 1 in which said second control valve is constituted by pertinent parts of the input shaft, the actuated member, and said wall of the enclose which define said other hydraulic fluid supply and discharge passageways, grooves formed in an outer surface of the actuated member to perform valve action cooperatively with said passageways and communicating with third passageways leading to the peripheral surface of the input shaft, grooves formed in said peripheral surface of the input shaft to perform valve action cooperatively with said third passageways and communicating with the first mentioned passageways formed in the input shaft.
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) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |