John R Dziedzic

US Patent:

6732651, May 11, 2004

Filed:

Mar 22, 2002

Appl. No.:

10/104244

Inventors:

John M. Dziedzic - Bartlett IL
Kenneth H. Giesen - Northbrook IL
Erik A. Leman - DeKalb IL

Assignee:

Oxy-Dry Corporation - Itasca IL

International Classification:

B41F 3500

US Classification:

1014241, 34266

Abstract:

A printing press with an infrared dryer unit is provided with a safety system for detecting overheating and sheet jamming conditions. The safety system has a temperature sensor disposed to directly detect the temperature of a passing printed sheet and to generate an output signal proportional to the detected temperature. As the printed sheets pass by the sensor, the sensor output signal contains a pulse for each passing sheet. A controller monitors temperature readings derived from the output signal of the temperature sensor for identifying a sign of overheating. The controller also determines whether there is an interruption in the flow of sheets by monitoring the pulses in the sensor output signal. In the case the sensor fails to provide pulses for a predetermined time, the controller generates a control signal indicating the detection of an interruption in the sheet flow.