US3768406A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sheet gripper
Assignee: Sächsisches Institut für die Druckindustrie
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Filing: 1972-07-03
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Granted: 1973-10-30
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Expires: 1992-07-03
Abstract
Abstract Apparatus for gripping a sheet on a support surface. Gripper fingers are moved by first electromagnets, for gripping the sheet between the fingers and said surface. The fingers are then held against the sheet by second electromagnets which are arranged in the support surface and cause the fingers to hold the sheet against said surface with an added holding force.
Inventors
- 👤 R Gutsche
- 👤 M Hanske
- 👤 G Lungwitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:21
CPC Classifications
B; B41; B41F; B41F21/00; B41F21/10; B41F21/104
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
91 words
In a device for clamping a sheet, particularly on a cylinder of a printing press: a sheet support body; a rigid shaft secured thereto; a system of gripper fingers rotatably mounted on said shaft; a firsT system of electromagnets in said body; means connecting the first electromagnets with the gripper fingers to produce sheet closing forces between the gripper fingers and said body; and a second system of electromagnets in said body, providing means for applying holding forces between said fingers and the second system of electromagnets for holding the sheet.
Claim 2
Dependent Claim
91 words
In a device for clamping a sheet, particularly on a cylinder of a printing press: a sheet support body; a rigid shaft secured thereto; a system of gripper fingers rotatably mounted on said shaft; a firsT system of electromagnets in said body; means connecting the first electromagnets with the gripper fingers to produce sheet closing forces between the gripper fingers and said body; and a second system of electromagnets in said body, providing means for applying holding forces between said fingers and the second system of electromagnets for holding the sheet.
Claim 3
Dependent Claim
27 words
Apparatus according to claim 1, wherein each of the first-mentioned electromagnets is a push-pull magnet for moving a gripper finger in either direction relative to said body.
Claim 4
Dependent Claim
26 words
Apparatus according to claim 1, wherein the first-mentioned electromagnets additionally have spring means for returning the gripper fingers to non-closing positions when the magnets are deenergized.
Claim 5
Dependent Claim
18 words
Apparatus according to claim 1, additionally including slip ring means for periodic control of both sets of electromagnets.
Claim 6
Dependent Claim
109 words
Apparatus for clamping sheets, particularly on a cylinder of a printing press, comprising a sheet support body; a rigid shaft secured thereto; a system of gripper fingers rotatably mounted on said shaft; a first system of electromagnets rotationally mounted in said body and having parts movably mounted; means connecting said movable parts of the first electromagnets with the gripper fingers for gripping a sheet between the gripper fingers and said body; and a second system of electromagnets rigidly mounted in said body to provide means for applying holding forces between said fingers and the second system of electromagnets and for thereby firmly holding the gripped sheet to said body.
Claim 7
Dependent Claim
109 words
Apparatus for clamping sheets, particularly on a cylinder of a printing press, comprising a sheet support body; a rigid shaft secured thereto; a system of gripper fingers rotatably mounted on said shaft; a first system of electromagnets rotationally mounted in said body and having parts movably mounted; means connecting said movable parts of the first electromagnets with the gripper fingers for gripping a sheet between the gripper fingers and said body; and a second system of electromagnets rigidly mounted in said body to provide means for applying holding forces between said fingers and the second system of electromagnets and for thereby firmly holding the gripped sheet to said body.
Claim 8
Dependent Claim
19 words
Apparatus according to claim 5, wherein each of the second-mentioned electromagnets is mounted opposite one of said gripper fingers.
Claim 9
Dependent Claim
13 words
Apparatus according to claim 5, wherein the gripper fingers are of magnetic material.
Claim 10
Dependent Claim
25 words
Apparatus according to claim 5, wherein each of the second-mentioned electromagnets has a pole shoe surface flush with the surface of the sheet support body.
References Cited (Backward Citations)
DE259237C
Cited
US1436688A
Cited
FR590735A
Cited
US2486703A
Cited
US2597178A
Cited
US2730949A
Cited
US2987656A
Cited
GB937539A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |