US4029456A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rapid load-relieve device for continuous press
Assignee: Eduard Kuesters Maschinenfabrik GmbH and Co KG
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Filing: 1975-10-10
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Granted: 1977-06-14
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Expires: 1995-10-10
Abstract
Abstract A rapid load relief device to prevent fast build-up of pressure in a continuous press of the type having two rotatively driven endless conveyor belts forming opposed, substantially linear spans defining a press zone with press platens applying pressure through the travelling spans to work carried therebetween and in which a plurality of hydraulic cylinders or spindles are inserted between the press platens and rigid supports with pressure supplied to the cylinders through a pressure-controlling valve which is sensitive to the movement of the pressure platen to regulate the pressure in the cylinders maintaining a constant platen spacing in which means are provided which, upon sensing an excess pressure, immediately separate the press platens.
Inventors
- 👤 Karl-Heinz Ahrweiler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:21
CPC Classifications
B; B30; B30B; B30B15/00; B30B15/28; B30B15/281; B30B15/16; B30B15/163; B30B5/00; B30B5/04; B30B5/06
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
97 words
In a press having two press platens which are brought toward each other by at least one force exerting element utilizing a fluid medium under pressure, the elements designed to abut against a stop as long as a pre-determined operating pressure between the spans is not exceeded, the improvement comprising: a. means for sensing the movement of the force exerting element away from the stop and providing an output indicative thereof; and b. means responsive to the output of said sensing means for moving said press platens apart in a direction opposite to their normal operating direction.
Claim 2
Dependent Claim
97 words
In a press having two press platens which are brought toward each other by at least one force exerting element utilizing a fluid medium under pressure, the elements designed to abut against a stop as long as a pre-determined operating pressure between the spans is not exceeded, the improvement comprising: a. means for sensing the movement of the force exerting element away from the stop and providing an output indicative thereof; and b. means responsive to the output of said sensing means for moving said press platens apart in a direction opposite to their normal operating direction.
Claim 3
Dependent Claim
44 words
A press according to claim 1 wherein said force exerting element is a double-acting force exerting element and wherein said means for moving apart said press platens comprises means for operating said force exerting element in a direction opposite to its normal operating direction.
Claim 4
Dependent Claim
21 words
Apparatus according to claim 2 wherein said double-acting element is a piston and cylinder unit actuated by a medium under pressure.
Claim 5
Dependent Claim
61 words
Apparatus according to claim 3 wherein said means for sensing comprises means arranged to have a drop in pressure when the piston and cylinder of said force exerting element move apart from a stop position and means responsive thereto for applying a fluid pressure to the side of said piston opposite the side to which its normal operating pressure is applied.
Claim 6
Dependent Claim
23 words
Apparatus according to claim 4 wherein said means for applying pressure to the opposite side of said piston includes a fluid pressure accumulator.
Claim 7
Dependent Claim
48 words
Apparatus according to claim 5 wherein said means for supplying said pressure to the other side of said cylinder includes a valve for coupling said pressure accumulator to the other side of said piston and wherein said valve is operated by said means sensing a drop in pressure.
Claim 8
Dependent Claim
77 words
Apparatus according to claim 6 wherein said piston has a stop comprising a sealing web at one end defining an enclosed space at the top of the cylinder when said piston is in abutment therewith and wherein said means for sensing a drop in pressure comprises means for supplying pressure to said closed space and means for sensing a drop in pressure in said space caused by said piston moving away from the top of said cylinder.
Claim 9
Dependent Claim
13 words
Apparatus according to claim 7 wherein said sealing web has an annular shape.
Claim 10
Dependent Claim
17 words
Apparatus according to claim 1 and further including a stop limiting the spacing of said press platens.
Claim 11
Dependent Claim
32 words
Apparatus according to claim 6 and further including a second valve responsive to the output of said sensing means for disconnecting said cylinders and pistons from their normal source of operating fluid.
References Cited (Backward Citations)
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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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |