Patent US3730086A successfully refreshed from Google Patents.
US3730086A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Printing press film sensor
Assignee: Harris Graphics Corp
•
Filing: 1970-06-10
•
Granted: 1973-05-01
•
Expires: 1990-06-10
Abstract
Abstract An improved sensor has been provided for measuring the thickness of the film of dampening fluid on one of the rolls in the dampening mechanism of a lithographic printing press. The sensor comprises a capacitor formed between a sensor roller which runs in contact with the dampener form roll and a capacitor plate disposed concentric with the roller. The sensor roller which runs in contact with the dampener form roll has a film of dampening fluid thereon the thickness of which is dependent upon the thickness of the film of fluid on the dampener form roll. The sensor senses the change in capacitance of the capacitor which results primarily from the change in the dielectric of the space between the capacitor plate and the roller. The changes in the dielectric result from changes in the thickness of the film of dampening fluid on the roller. A frame is provided to support the capacitor plate and the sensor roller and the frame minimizes vibration between the roller and the capacitor plate to thereby provide an accurate sensor.
Inventors
- 👤 W Dauterman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:17
CPC Classifications
B; B41; B41F; B41F7/00; B41F7/20; B41F7/24; G; G01; G01B; G01B7/00; G01B7/02; G01B7/06; G01B7/08; G01B7/085
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
408 words
In a printing press having a dampening mechanism for applying water to a plate on a plate cylinder and an inker mechanism having ink transfer means for transferRing ink from an ink supply to the plate on the plate cylinder and which transfer means has water thereon the amount of which is dependent upon the amount of water being transferred to the plate by the dampening mechanism, a sensor for measuring the amount of fluid transferred to the plate comprising means having a hydrophilic surface thereon for engaging with the ink transfer means and adapted to have a film of water transferred thereto the thickness of which is dependent upon the amount of water on the transfer means and the amount of water being transferred to the plate cylinder, and means associated with said hydrophilic surface for measuring the film thickness of the water on said hydrophilic surface and to render an indication of the amount of water being transferred to the plate cylinder, said means having a hydrophilic surface thereon comprising a sensor roller having an outer hydrophilic surface thereon, said ink transfer means comprises an ink form roll, said sensor roller being adapted to have said hydrophilic surface thereof rotatably engage with said ink form roll to pick up a film of water from said ink form roll and said means associated with said hydrophilic surface comprising a capacitance plate disposed adjacent to said hydrophilic surface of said sensor roller, said sensor roller and said capacitance plate forming a capacitor for sensing the film thickness of said water on said hydrophilic surface of said sensor roller, said sensor roller having a first surface portion thereon which is adapted to rotatably engage with said ink form roll and have a film of fluid transferred thereto which has a film thickness which is dependent on the film thickness of the dampening fluid which is transferred to the plate on the plate cylinder of the press and a second surface portion thereon which is spaced from said first surface portion, said second surface portion remaining free of said dampening fluid, said capacitance plate being disposed adjacent to said first surface portion of said roller and spaced apart from said second surface portion of said roller and further including a second sensor capacitance plate disposed adjacent to said second surface portion of said roller and spaced apart from said first surface portion of said roller for providing a reference signal.
Claim 2
Dependent Claim
408 words
In a printing press having a dampening mechanism for applying water to a plate on a plate cylinder and an inker mechanism having ink transfer means for transferRing ink from an ink supply to the plate on the plate cylinder and which transfer means has water thereon the amount of which is dependent upon the amount of water being transferred to the plate by the dampening mechanism, a sensor for measuring the amount of fluid transferred to the plate comprising means having a hydrophilic surface thereon for engaging with the ink transfer means and adapted to have a film of water transferred thereto the thickness of which is dependent upon the amount of water on the transfer means and the amount of water being transferred to the plate cylinder, and means associated with said hydrophilic surface for measuring the film thickness of the water on said hydrophilic surface and to render an indication of the amount of water being transferred to the plate cylinder, said means having a hydrophilic surface thereon comprising a sensor roller having an outer hydrophilic surface thereon, said ink transfer means comprises an ink form roll, said sensor roller being adapted to have said hydrophilic surface thereof rotatably engage with said ink form roll to pick up a film of water from said ink form roll and said means associated with said hydrophilic surface comprising a capacitance plate disposed adjacent to said hydrophilic surface of said sensor roller, said sensor roller and said capacitance plate forming a capacitor for sensing the film thickness of said water on said hydrophilic surface of said sensor roller, said sensor roller having a first surface portion thereon which is adapted to rotatably engage with said ink form roll and have a film of fluid transferred thereto which has a film thickness which is dependent on the film thickness of the dampening fluid which is transferred to the plate on the plate cylinder of the press and a second surface portion thereon which is spaced from said first surface portion, said second surface portion remaining free of said dampening fluid, said capacitance plate being disposed adjacent to said first surface portion of said roller and spaced apart from said second surface portion of said roller and further including a second sensor capacitance plate disposed adjacent to said second surface portion of said roller and spaced apart from said first surface portion of said roller for providing a reference signal.
Claim 3
Dependent Claim
51 words
In a printing press, a capacitance film sensor as defined in claim 1 wherein said second capacitance plate and said second surface portion of said roller cooperate to form a second capacitor for sensing changes in the spacing between said second capacitance plate and said second surface portion of said roller.
References Cited (Backward Citations)
US2103254A
Cited
US3094065A
Cited
US3146706A
Cited
US3227951A
Cited
US3191528A
Cited
US3412677A
Cited
US3499383A
Cited
US3584579A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |