Patent US4612081A successfully refreshed from Google Patents.
US4612081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure equalizing pad for heated plate presses
Assignee: Maschinenfabrik J Dieffenbacher GmbH and Co
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Filing: 1985-08-13
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Granted: 1986-09-16
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Expires: 2005-08-13
Abstract
Abstract A pressure equalizing pad for presses with heated plates for the production of compacts, laminates, etc. has a press stand with a movable ram. An upper pressure plate is attached to the ram and a bed-pressure plate is positioned on a press bed with a hydrostatic pressure pad thereon. The hydrostatic pressure pad includes a thin steel sheet floatingly maintained by an oil medium, a flexible edge seal between the steel sheet and the bed-pressure plate, as well as rings and gaskets to form the improved device.
Inventors
- 👤 Rolf Kasper
- 👤 Friedrich B. Bielfeldt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:09
CPC Classifications
B; B30; B30B; B30B15/00; B30B15/06; B30B15/062; B30B15/061
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
58 words
A pressure equalizing pad for heated plate presses and the like, comprising: (a) a press stand having a movable ram thereon; (b) a stationary press bed on said stand; (c) an upper pressure plate attached to said ram, and a bed-pressure plate positioned on said press bed; and (d) a hydrostatic pressure pad positioned on said bed-pressure plate.
Claim 2
Dependent Claim
58 words
A pressure equalizing pad for heated plate presses and the like, comprising: (a) a press stand having a movable ram thereon; (b) a stationary press bed on said stand; (c) an upper pressure plate attached to said ram, and a bed-pressure plate positioned on said press bed; and (d) a hydrostatic pressure pad positioned on said bed-pressure plate.
Claim 3
Dependent Claim
20 words
The pad of claim 1 wherein said hydrostatic pressure pad includes a thin metal sheet floatingly maintained by a medium.
Claim 4
Dependent Claim
18 words
The pad of claim 2 including a flexible edge seal between said metal sheet and said bed-pressure plate.
Claim 5
Dependent Claim
37 words
The pad of claim 3 wherein said seal comprises at least two grooves in said bed-pressure plate and a rubber ring in each of said grooves, said rings being held in said grooves by said metal sheet.
Claim 6
Dependent Claim
39 words
The pad of claim 4 wherein said metal plate is pressured by means of a plurality of screws against said bed-pressure plate and wherein the thickness of said hydrostatic pressure pad is formed by the thickness of said rings.
Claim 7
Dependent Claim
11 words
The pad of claim 2 wherein said metal plate is steel.
Claim 8
Dependent Claim
27 words
The pad of claim 2 wherein said metal plate is vulcanized along its peripheral edge to said bed-pressure plate by means of an endless flat rubber gasket.
Claim 9
Dependent Claim
24 words
The pad of claim 7 wherein the width of said gasket is dimensioned in accordance with the compacting pressure of the heated plate press.
Claim 10
Dependent Claim
47 words
The pad of claim 1 including a pressure frame mounted on said ram, said pressure frame surrounding said upper pressure plate; an upper press plate elastically mounted on said upper pressure plate and wherein said upper pressure frame projects over said upper press plate a given distance.
Claim 11
Dependent Claim
34 words
The pad of claim 1 including a plurality of heating channels in at least one of said plates, feeder channels connected to said heating channels, and a vacuum pump connected to said feeder channels.
Claim 12
Dependent Claim
10 words
The pad of claim 2 wherein said medium is oil.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-15 | 1990-03-17 | 1990-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-15 | 1994-03-17 | 1994-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-15 | 1998-03-17 | 1998-09-16 | $7700.00 | Window Closed / Lapsed |