Patent US3757817A successfully refreshed from Google Patents.
US3757817A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tandem control valve
Assignee: McDonnell Douglas Corp
•
Filing: 1972-08-23
•
Granted: 1973-09-11
•
Expires: 1992-08-23
Abstract
Abstract A control valve for a hydraulic actuated assembly which includes two valve slides which are resiliently connected in tandem to a control input. If one of the slides jams, the other slide can be moved to cause hydraulic lock of the hydraulic actuator.
Inventors
- 👤 M Wheeler
- 👤 R Rothi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:33
CPC Classifications
F; F15; F15B; F15B18/00; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87169
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
98 words
A control valve including: a housing having a first and second set of valve ports therein; a first switching member adapted to move in said housing to control communication through said first set of ports; a second switching member adapted to move in said housing to control communication through said second set of ports; first preloaded resilient means connected to said first switching member; second preloaded resilient means connected to said second switching member; and input means connected to said first and second preloaded resilient means to releasably feed input motion to said first and second switching members.
Claim 2
Dependent Claim
98 words
A control valve including: a housing having a first and second set of valve ports therein; a first switching member adapted to move in said housing to control communication through said first set of ports; a second switching member adapted to move in said housing to control communication through said second set of ports; first preloaded resilient means connected to said first switching member; second preloaded resilient means connected to said second switching member; and input means connected to said first and second preloaded resilient means to releasably feed input motion to said first and second switching members.
Claim 3
Dependent Claim
42 words
The control valve defined in claim 1 wherein: said input means are between said first and second switching members so that a failure associated with one of said switching members is not likely to cause the failure of said other switching member.
Claim 4
Dependent Claim
64 words
The control valve defined in claim 1 wherein: said first and second switching members are sleeve members adapted to slide along an axis within said housing; and said input means include an input shaft which extends along the housing axis through said sleeve members and is connected to said first and second preloaded resilient means to feed input motion therethrough to said sleeve members.
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) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |