US3568976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Valve for pressing machine
Assignee: NEW YORK PRESSING MACHINERY CORP
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Filing: 1969-08-28
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Granted: 1971-03-09
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Expires: 1989-08-28
Abstract
Abstract A valve for a pressing machine formed as a closed unit having a central shaft which controls a valve at one end for permitting the delivery of live steam to a pressing surface, with operation of the valve being controlled by means of a piston at the other end of the shaft operated on by air pressure, with a seal surrounding the shaft to prevent communication between the live steam and the compressed air.
Inventors
- 👤 Fred W Thumm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:24
CPC Classifications
D; D06; D06F; D06F71/00; D06F71/32; D06F71/34; F; F16; F16K; F16K31/00; F16K31/12; F16K31/122; F16K31/1221
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
159 words
A valve for a pressing machine comprising a body including a first chamber at one end, a second chamber at an opposite end, steam inlet and outlet passages communicating with said first chamber, a valve seat surrounding said inlet passage, an air inlet passage communicating with said second chamber, a bore interconnecting said first and second chambers, and an undercut at an end of said bore within said first chamber, a first piston slidably mounted in said first chamber for engaging said valve seat for closing said valve, a piston rod slidably mounted in said bore and having one end connected to said first piston, a second piston slidably mounted in said second chamber, said second piston being connected to the other end of said piston rod, and biasing apparatus acting between said undercut and said first piston for biasing said first piston toward said valve seat and sealing said first chamber from said bore about said piston rod.
Claim 2
Dependent Claim
159 words
A valve for a pressing machine comprising a body including a first chamber at one end, a second chamber at an opposite end, steam inlet and outlet passages communicating with said first chamber, a valve seat surrounding said inlet passage, an air inlet passage communicating with said second chamber, a bore interconnecting said first and second chambers, and an undercut at an end of said bore within said first chamber, a first piston slidably mounted in said first chamber for engaging said valve seat for closing said valve, a piston rod slidably mounted in said bore and having one end connected to said first piston, a second piston slidably mounted in said second chamber, said second piston being connected to the other end of said piston rod, and biasing apparatus acting between said undercut and said first piston for biasing said first piston toward said valve seat and sealing said first chamber from said bore about said piston rod.
Claim 3
Dependent Claim
25 words
A valve as claimed in claim 1, wherein said biasing apparatus includes a sealing ring surrounding said piston rod and extending partially into said undercut.
Claim 4
Dependent Claim
40 words
A valve as claimed in claim 1, wherein said biasing apparatus includes a sealing ring adjacent said undercut, a plate in contact with a surface of said sealing ring and a spring acting between said plate and said first piston.
Claim 5
Dependent Claim
29 words
A valve as claimed in claim 3, wherein a portion of said sealing ring is received in said undercut and said plate biases said sealing ring into said undercut.
Claim 6
Dependent Claim
19 words
A valve as claimed in claim 4, wherein said undercut is annular and said sealing ring is an O-ring.
Claim 7
Dependent Claim
66 words
A valve as claimed in claim 5, wherein the depth of said undercut is less than the thickness of said O-ring, whereby, when said O-ring is located in said undercut, a portion of said O-ring extends into said first cylinder for engagement by said plate and said spring acting on said plate urges said O-ring into said undercut and in close engagement with said piston rod.
Claim 8
Dependent Claim
14 words
A valve as claimed in claim 6, wherein said O-ring is fabricated of Teflon.
References Cited (Backward Citations)
US1921551A
Cited
US3188048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |