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US3719142A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic plate clamping and discharging device for use in offset printing press

Assignee: Ricoh Co Ltd
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Filing: 1971-11-24
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Granted: 1973-03-06
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Expires: 1991-11-24
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Abstract

Abstract In an offset printing plate having an automatic plate clamping and discharging device, light reflected from or transmitted through both side edges of a plate feed passageway and/or plate cylinder is intercepted by a pair of photoelectric effect elements whereby mis-alignment of the plate edges provides a detectable different electrical output in each photoelectric element. When the printing plate is fed under normal conditions and/or when the printing plate is correctly clamped around the plate cylinder, only a clamp means for clamping the plate around the plate cylinder is actuated. When the plate is fed under abnormal conditions and/or is not correctly clamped, a plate discharge means is also actuated in addition to the clamp means so that the plate which is once clamped, is removed from the plate cylinder and discharged out of the printing press. The plate clamp means as well as discharge means are controlled by electronic circuit means.

Inventors

  • 👤 T Abe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 19:56
CPC Classifications
B; B41; B41F; B41F7/00; B41F7/02; B41F27/00; B41F27/12; B41F27/1206; B41F33/00; B41L; B41L29/00; B41L29/12; B41L29/14; B41L29/16

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 177 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of a printing plate being fed, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-readyoperation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 2
Dependent Claim 177 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of a printing plate being fed, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-readyoperation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 3
Dependent Claim 177 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of a printing plate being fed, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-ready-operation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 4
Dependent Claim 177 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of a printing plate being fed, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-ready-operation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 5
Dependent Claim 48 words
An automatic plate clamping and discharging device as set forth in claim 1 wherein said detecting means detects the conditions and position of the plate by the difference in quantity of reflected light from the plate receive in two photoelectric elements disposed on both sides of the plate.
Claim 6
Dependent Claim 142 words
An automatic plate clamping and discharging device as set forth in claim 1 wherein said clamp means comprises a plate clamp lever integral with a plate clamp and a clamping pawl, a spring for biasing said plate clamp lever in the direction in which said plate clamp is closed, a lever for rotating said plate clamp lever in the direction in which said clamp is opened, and a spring for returning said lever; and said plate discharge means comprises a plate discharge roller adapted to push a part adjacent to the leading edge of the plate, when the latter is discharged, to cause said leading edge of said plate to bow, supporter means for rotatably carrying said plate discharge roller, a rotatable plate discharge clamp a pair of plate discharge runners disposed adjacent to the trailing end of said plate discharge clamp.
Claim 7
Dependent Claim 182 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of the plate which is being wrapped around a plate cylinder, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-ready-operation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 8
Dependent Claim 182 words
An automatic plate clamping and discharging device for use in an offset printing press comprising a. means for detecting the deviation in condition and position of the plate which is being wrapped around a plate cylinder, b. means for clamping the plate around a plate cylinder, c. means for removing the plate from said plate cylinder and discharging said plate, d. electronic circuit means for opening said clamp means in response to the plate feed signal, e. electronic circuit means for generating the printing-ready-operation signal in response to the signal from said detecting means representing that the plate is fed under normal conditions, f. electronic circuit means for actuating said plate discharge means to discharge the plate in response to the signal from said detecting means representing that the plate is fed under abnormal conditions, g. electronic circuit means for resetting said clamp means and said discharge means, and h. electronic circuit means for opening said clamp means and actuating said plate discharge means to discharge the plate in response to the signal representing that a predetermined number of sheets is printed.
Claim 9
Dependent Claim 48 words
An automatic plate clamping and discharging device as set forth in claim 4 wherein said Detecting means detects the conditions and position of the plate by the difference in quantity of reflected light from the plate received in two photoelectric elements disposed on both sides of the plate.
Claim 10
Dependent Claim 142 words
An automatic plate clamping and discharging device as set forth in claim 4 wherein said clamp means comprises a plate clamp lever integral with a plate clamp and a clamping pawl, a spring for biasing said plate clamp lever in the direction in which said plate clamp is closed, a lever for rotating said plate clamp lever in the direction in which said clamp is opened, and a spring for returning said lever; and said plate discharge means comprises a plate discharge roller adapted to push a part adjacent to the leading edge of the plate, when the latter is discharged, to cause said leading edge of said plate to bow, supporter means for rotatably carrying said plate discharge roller, a rotatable plate discharge clamp a pair of plate discharge runners disposed adjacent to the trailing end of said plate discharge clamp.

References Cited (Backward Citations)

US2668363A Cited
US2711691A Cited
US3310304A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-03-05 1976-09-04 1977-03-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-03-05 1980-09-04 1981-03-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-03-05 1984-09-04 1985-03-06 $7700.00 Window Closed / Lapsed

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