Patent US3877484A successfully refreshed from Google Patents.
US3877484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pneumatic relay
Assignee: BWB Controls Inc
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Filing: 1973-09-06
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Granted: 1975-04-15
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Expires: 1993-09-06
Abstract
Abstract A fluid valve operative based on a pressure differential through the utilization of different size pressure receiving piston faces. A first fluid, through pressure on an enlarged piston face, maintains a valve spool so shifted as to allow for a through passage of a second fluid. Upon a blocking of the first fluid, the second fluid, acting on a relatively smaller valve surface, actuates the valve and blocks through passage of the second fluid. The shifting of the valve presents yet a smaller pressure receiving face to the first fluid which, in conjunction with an exhaust port, provides a fail safe lock out requiring manual resetting of the relay.
Inventors
- 👤 Gerold F Theriot
- 👤 Frank M Hoofnagle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:10
CPC Classifications
F; F16; F16K; F16K17/00; F16K17/02; F16K17/04; F16K17/08; F16K17/082; F16K17/048; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7723; Y10T137/7725; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/86622; Y10T137/8663
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
262 words
A valve comprising a valve body, an elongated bore within said body, a first fluid inlet port, an outlet port, a bleed port, a second fluid inlet port, a valve member slidable within said bore, said valve member presenting a first pressure surface on said valve member exposed to said first fLuid inlet port, a second pressure surface on said valve member exposed to said second fluid inlet port, said valve being selectively shiftable between a first position allowing communication between the first fluid inlet port and the outlet port and precluding communication between the outlet port and the bleed port, and a second position allowing communication between said outlet port and said bleed port and precluding communication between said first fluid inlet port and said outlet port, a greater total force on said second pressure surface than on said first pressure surface maintaining said valve member in said first position, a greater total force on said first pressure surface than on said second pressure surface moving said valve to said second position, and means for effectively precluiding fluid pressure supplied said valve through said second fluid inlet port from moving said valve from said second position to said first position, said precluding means including a) an exhaust port in fluid communication with said second fluid inlet port only when said valve member is in a further position intermediate said first and second positions, and b) seal means preventing fluid communication between said exhaust port and said second fluid inlet port when said valve member is in said first and second positions.
Claim 2
Dependent Claim
262 words
A valve comprising a valve body, an elongated bore within said body, a first fluid inlet port, an outlet port, a bleed port, a second fluid inlet port, a valve member slidable within said bore, said valve member presenting a first pressure surface on said valve member exposed to said first fLuid inlet port, a second pressure surface on said valve member exposed to said second fluid inlet port, said valve being selectively shiftable between a first position allowing communication between the first fluid inlet port and the outlet port and precluding communication between the outlet port and the bleed port, and a second position allowing communication between said outlet port and said bleed port and precluding communication between said first fluid inlet port and said outlet port, a greater total force on said second pressure surface than on said first pressure surface maintaining said valve member in said first position, a greater total force on said first pressure surface than on said second pressure surface moving said valve to said second position, and means for effectively precluiding fluid pressure supplied said valve through said second fluid inlet port from moving said valve from said second position to said first position, said precluding means including a) an exhaust port in fluid communication with said second fluid inlet port only when said valve member is in a further position intermediate said first and second positions, and b) seal means preventing fluid communication between said exhaust port and said second fluid inlet port when said valve member is in said first and second positions.
Claim 3
Dependent Claim
244 words
A valve comprising a valve body, an elongated bore within said body, a first fluid inlet port, an outlet port, a bleed port, a second fluid inlet port, a valve member slidable within said bore, said valve member presenting a first fluid pressure surface on said valve member exposed to said first fluid inlet port, a second fluid pressure surface on said valve member exposed to said second fluid inlet port, said valve member being selectively shiftable between a first position allowing communication between the first fluid inlet port and the outlet port and precluding communication between the outlet port and the bleed port, and a second position allowing communication between said outlet port and said bleed port and precluding communication between said first fluid inlet port and said outlet port, a greater total force on said second pressure surface than on said first pressure surface maintaining said valve in said first position, a greater total force on said first pressure surface than on said second pressure surface moving said valve to said second position, a valve seat about said second fluid inlet port, said valve member including a portion thereon receivable within said seat to close said second fluid inlet port upon movement of the valve member from the first position thereof to the second position, and an exhaust port selectively communicated with said second fluid inlet port when said valve member is in a position intermediate said first and said second position.
Claim 4
Dependent Claim
244 words
A valve comprising a valve body, an elongated bore within said body, a first fluid inlet port, an outlet port, a bleed port, a second fluid inlet port, a valve member slidable within said bore, said valve member presenting a first fluid pressure surface on said valve member exposed to said first fluid inlet port, a second fluid pressure surface on said valve member exposed to said second fluid inlet port, said valve member being selectively shiftable between a first position allowing communication between the first fluid inlet port and the outlet port and precluding communication between the outlet port and the bleed port, and a second position allowing communication between said outlet port and said bleed port and precluding communication between said first fluid inlet port and said outlet port, a greater total force on said second pressure surface than on said first pressure surface maintaining said valve in said first position, a greater total force on said first pressure surface than on said second pressure surface moving said valve to said second position, a valve seat about said second fluid inlet port, said valve member including a portion thereon receivable within said seat to close said second fluid inlet port upon movement of the valve member from the first position thereof to the second position, and an exhaust port selectively communicated with said second fluid inlet port when said valve member is in a position intermediate said first and said second position.
Claim 5
Dependent Claim
21 words
The valve of claim 2 wherein said second pressure surface is of a substantially greater area than said first pressure surface.
Claim 6
Dependent Claim
34 words
The valve of claim 3 wherein said seat received valve portion presents a pressure receiving face directed toward said second fluid inlet port which has a substantially smaller area than said first pressure surface.
Claim 7
Dependent Claim
26 words
The valve of claim 4 wherein said valve member projects outwardly beyond a first end of said valve body for a manual gripping and manipulation thereof.
Claim 8
Dependent Claim
38 words
The valve of claim 5 wherein said second fluid inlet port is defined in the second end of said body, said bore and said valve member extending longitudinally through said body between the first and second ends thereof.
Claim 9
Dependent Claim
42 words
The valve of claim 6 wherein said outlet port is laterally directed through said body in inwardly spaced relation to said first end, said first inlet fluid port being laterally directed through said body in inwardly spaced relation to said outlet port.
Claim 10
Dependent Claim
23 words
The valve of claim 7 wherein said bleed port is laterally directed through said body between said first end and said outlet port.
Claim 11
Dependent Claim
55 words
The valve of claim 8 wherein said valve member includes a first bore engagiNg seal which, in the first position of the valve member, is orientated between the outlet port and the bleed port, and in the second position of the valve member is orientated between the outlet port and the first fluid inlet port.
Claim 12
Dependent Claim
29 words
The valve of claim 9 wherein said exhaust port is laterally directed through said body between the second end of the valve body and the first fluid inlet port.
Claim 13
Dependent Claim
42 words
The valve of claim 10 wherein said first pressure receiving surface on the valve member is orientated between the first fluid inlet port and the exhaust port, and bore engaging seal means about said valve member at said first pressure receiving surface.
Claim 14
Dependent Claim
42 words
The valve of claim 11 wherein said second pressure receiving surface on said valve member is orientated between the exhaust port and the second fluid inlet port, and bore engaging seal means about said valve member at said second pressure receiving surface.
Claim 15
Dependent Claim
123 words
The valve of claim 12 wherein said bore is of a constant diameter, engageable by the first bore engaging seal, between the first end of the body and a point just beyond the first fluid inlet port, said bore subsequently being enlarged to a point just beyond the exhaust port and sealingly engaged by the seal at the first pressure surface, said bore being further enlarged beyond the exhaust port and sealingly engaged by the seal at the second pressure surface, said bore, inward of the second fluid inlet port, being of a diameter greater than that of the second pressure surface and seal thereabout so as to selectively provide a fluid passage from the second fluid inlet port to the exhaust port.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |