Patent US4643225A successfully refreshed from Google Patents.
US4643225A
Expired / Lapsed
US
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Pressure regulating valve
Assignee: Bosch Rexroth AG
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Filing: 1985-02-25
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Granted: 1987-02-17
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Expires: 2005-02-25
Abstract
Abstract A proportional solenoid operated pressure regulating valve is disclosed. First and second metering spools are respectively mounted for movement inside first and second control spools. Each metering spool responds to a fluid pressure being controlled at a respective operating port.
Inventors
- 👤 Rainer Imhof
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:44
CPC Classifications
F; F15; F15B; F15B13/00; F15B13/02; F15B13/04; F15B13/0401; F15B13/0402; F15B13/0403; F15B13/044; G; G05; G05D; G05D16/00; G05D16/20; G05D16/2006; G05D16/2013; G05D16/2024; G05D16/2093; G05D16/2097; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/86582; Y10T137/86614; Y10T137/86622; Y10T137/87169; Y10T137/87217
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
212 words
A pressure regulating valve comprising: a valve housing having a longitudinal bore defined by an inner bore surface; first and second control spools reciprocally mounted with outer ends and opposing spaced inner ends for movement in said housing bore between a rest position and an operating position, each spool defining with said inner bore surface an operating chamber adapted to be connected to a pressure fluid source in said operating position and disconnected in said rest position and each adapted to be connected to a respective load so fluid flows to said load in said operating position, each spool having a spool bore in communication with said operating chamber and defining a pressure metering area smaller than the cross-sectional area of the control spool; first and second metering spools respectively mounted for movement in said spool bores and extending into the space between said control spools to abut, each said metering spool responding to pressure in the respective operating chamber to apply a force to both control spools; and first and second actuating means for applying a force respectively to the outer end of said control spools to cause said spools to move to said operating position, the forces produced by said metering spools opposing the force applied by said actuating means.
Claim 2
Dependent Claim
212 words
A pressure regulating valve comprising: a valve housing having a longitudinal bore defined by an inner bore surface; first and second control spools reciprocally mounted with outer ends and opposing spaced inner ends for movement in said housing bore between a rest position and an operating position, each spool defining with said inner bore surface an operating chamber adapted to be connected to a pressure fluid source in said operating position and disconnected in said rest position and each adapted to be connected to a respective load so fluid flows to said load in said operating position, each spool having a spool bore in communication with said operating chamber and defining a pressure metering area smaller than the cross-sectional area of the control spool; first and second metering spools respectively mounted for movement in said spool bores and extending into the space between said control spools to abut, each said metering spool responding to pressure in the respective operating chamber to apply a force to both control spools; and first and second actuating means for applying a force respectively to the outer end of said control spools to cause said spools to move to said operating position, the forces produced by said metering spools opposing the force applied by said actuating means.
Claim 3
Dependent Claim
25 words
A valve as in claim 1, wherein said actuating means respectively include proportional solenoids with a pin abutting said outer end of said control spool.
Claim 4
Dependent Claim
18 words
A valve as in claim 1, further including a spring between said inner ends of said control spools.
Claim 5
Dependent Claim
19 words
A valve as in claim 3, wherein said spring is a coil pressure spring extending between said inner ends.
Claim 6
Dependent Claim
40 words
A valve as in claim 1, wherein said control spools define respective pressure chambers on either side of the space between said control spools for communicating with said respective operating chambers when said control spool is in said operating position.
Claim 7
Dependent Claim
28 words
A valve as in claim 1, wherein said control spool has a cross bore and connecting bore for communicating and throttling said control bore with said operating chamber.
Claim 8
Dependent Claim
18 words
A valve as in claim 1 further including throttling conduits respectively connecting said loads to said operating chambers.
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) | 1990-02-16 | 1990-08-18 | 1991-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-16 | 1994-08-18 | 1995-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-16 | 1998-08-18 | 1999-02-17 | $7700.00 | Window Closed / Lapsed |