Patent US4572274A successfully refreshed from Google Patents.
US4572274A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for compacting granular molding materials
Assignee: Georg Fischer AG
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Filing: 1983-10-25
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Granted: 1986-02-25
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Expires: 2003-10-25
Abstract
Abstract The apparatus has a valve arrangement which opens rapidly due to priming or prestressing of the valve plate by the pressure in the pressure chamber. When the valve is closed, pressure, built up in the pressure chamber space closed by the valve, applies a force to the valve member in the direction of its open position. The valve member is held closed by a holder arrangement. Following the development of a predetermined pressure in the pressure chamber, the holder arrangement releases the valve member such that the pressure in the pressure chamber forces the valve member to its open position opening the pressure chamber passage and permitting the pressure medium to surge onto the surface of the molding material. This apparatus is suitable for all high-stressed gases which must be released suddenly.
Inventors
- 👤 Rainer Zimmermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:55
CPC Classifications
B; B22; B22C; B22C15/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
208 words
An apparatus for compacting granular molding materials, particularly foundry molding materials, by a surge of pressure of a gaseous medium, comprising: a pressure chamber having coupling means, mounted at an outlet of said pressure chamber, for forming a closed system with a molding unit in which molding material has been loosely poured; a passage providing fluid communication between said pressure chamber and said outlet, and having a valve seat facing away from said pressure chamber; a valve member moveable between an open position spaced from said valve seat and a closed position engaging said valve seat and closing said passage; a valve rod coupled to said valve member and controlling movement thereof; and closure means, coupled to said valve rod, for moving said valve member from said open position toward said closed position; holding means for releasably engaging and retaining said valve rod such that said valve member is held in said closed position and for releasing said valve rod and said valve member for movement to said open position by fluid pressure in said pressure chamber, said holding means being separate from and independent of said closure means; whereby said passage is quickly opened for passage of fluid pressure from said pressure chamber to the molding unit.
Claim 2
Independent Claim
208 words
An apparatus for compacting granular molding materials, particularly foundry molding materials, by a surge of pressure of a gaseous medium, comprising: a pressure chamber having coupling means, mounted at an outlet of said pressure chamber, for forming a closed system with a molding unit in which molding material has been loosely poured; a passage providing fluid communication between said pressure chamber and said outlet, and having a valve seat facing away from said pressure chamber; a valve member moveable between an open position spaced from said valve seat and a closed position engaging said valve seat and closing said passage; a valve rod coupled to said valve member and controlling movement thereof; and closure means, coupled to said valve rod, for moving said valve member from said open position toward said closed position; holding means for releasably engaging and retaining said valve rod such that said valve member is held in said closed position and for releasing said valve rod and said valve member for movement to said open position by fluid pressure in said pressure chamber, said holding means being separate from and independent of said closure means; whereby said passage is quickly opened for passage of fluid pressure from said pressure chamber to the molding unit.
Claim 3
Dependent Claim
38 words
An apparatus according to claim 1 wherein said holding means comprises clamp elements which retain said valve rod in position by a stationary frictional engagement and which release said valve rod by forming a sliding frictional engagement therebetween.
Claim 4
Dependent Claim
52 words
An apparatus according to claim 1 wherein said holding means comprises means for guiding said valve rod; and said valve rod has separated first and second parts, said first part being connected to a piston, said second part being connected to a follower, said first part being movably coupled to said follower.
Claim 5
Dependent Claim
37 words
An apparatus according to claim 1 wherein said valve member is connected to a piston thrust drive by said valve rod, said valve rod having a delayed-action switch between said valve member and said piston thrust drive.
Claim 6
Dependent Claim
13 words
An apparatus according to claim 1 wherein said holding means is hydraulically operated.
Claim 7
Dependent Claim
13 words
An apparatus according to claim 1 wherein said holding means is pneumatically operated.
Claim 8
Dependent Claim
13 words
An apparatus according to claim 1 wherein said holding means is electrically operated.
Claim 9
Dependent Claim
26 words
An apparatus according to claim 1 wherein accelerator supports extend about the periphery of said valve member and in a direction away from said pressure chamber.
Claim 10
Dependent Claim
25 words
An apparatus according to claim 1 wherein said holding means releases said valve rod when pressure in said pressure chamber is at least 1.2 bar.
Claim 11
Dependent Claim
24 words
An apparatus according to claim 1 wherein said holding means comprise at least one clamp element which moves radially relative to said valve rod.
Claim 12
Dependent Claim
21 words
An apparatus according to claim 1 wherein said holding means comprise clamp elements which move radially relative to said valve rod.
Claim 13
Dependent Claim
76 words
An apparatus according to claim 1 wherein said closure means is coupled to said valve rod by a follower and a stem, said follower and stem being relatively movable through a limited distance substantially corresponding to a distance traveled by said valve member in moving between said open and closed positions, such that said valve member can move independently of said closure means when said valve member moves from said closed position to said open position.
Claim 14
Dependent Claim
27 words
An apparatus according to claim 1 wherein said valve rod comprises an enlargement between said valve member and said closure means for releasably engaging said holding means.
Claim 15
Independent Claim
207 words
An apparatus for compacting granular molding materials, particularly foundry molding materials, by a surge of pressure of a gaseous medium, comprising: a pressure chamber having coupling means, mounted at an outlet of said pressure chamber, for forming a closed system with a molding unit in which molding material has been loosely poured; a passage providing fluid communication between said pressure chamber and said outlet, and having a valve seat facing away from said pressure chamber; a valve member moveable between an open position spaced from said valve seat and a closed position engaging said valve seat and closing said passage; a valve rod coupled to said valve member and controlling movement thereof; and holding means for releasably engaging and retaining said valve rod such that said valve member is held in said closed position and for releasing said valve rod and said valve member for movement to said open position by fluid pressure in said pressure chamber, said holding means including clamp elements which retain said valve rod in position by a stationary frictional engagement and which release said valve rod by forming a sliding frictional engagement therebetween; whereby said passage is quickly opened for passage of fluid pressure from said pressure chamber to the molding unit.
Claim 16
Independent Claim
207 words
An apparatus for compacting granular molding materials, particularly foundry molding materials, by a surge of pressure of a gaseous medium, comprising: a pressure chamber having coupling means, mounted at an outlet of said pressure chamber, for forming a closed system with a molding unit in which molding material has been loosely poured; a passage providing fluid communication between said pressure chamber and said outlet, and having a valve seat facing away from said pressure chamber; a valve member moveable between an open position spaced from said valve seat and a closed position engaging said valve seat and closing said passage; a valve rod coupled to said valve member and controlling movement thereof; and holding means for releasably engaging and retaining said valve rod such that said valve member is held in said closed position and for releasing said valve rod and said valve member for movement to said open position by fluid pressure in said pressure chamber, said holding means including clamp elements which retain said valve rod in position by a stationary frictional engagement and which release said valve rod by forming a sliding frictional engagement therebetween; whereby said passage is quickly opened for passage of fluid pressure from said pressure chamber to the molding unit.
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) | 1989-02-24 | 1989-08-26 | 1990-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-24 | 1993-08-26 | 1994-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-24 | 1997-08-26 | 1998-02-25 | $7700.00 | Window Closed / Lapsed |