Patent ID: 7725050
Filing Date: 2010-05-25
Classification: B41J,G03G

Abstract:
1. A heated drum assembly for use in a printer, the drum assembly comprising: a hollow drum having a circumferential wall that defines an outer boundary for an internal cavity, the hollow drum having a first end and a second end and a longitudinal axis about which the hollow drum rotates; at least two stationary heaters that are located within the internal cavity of the hollow drum to heat the circumferential wall as it passes by the heaters, one of the two stationary heaters being located near one end of the hollow drum and the other stationary heater being located near the other end of the hollow drum; a fan located at one of the two ends of the hollow drum and configured to direct air through the hollow drum; at least two temperature sensors, one temperature sensor being located proximate one of the two ends of the hollow drum, and the other temperature sensor being located proximate the other of the two ends of the hollow drum, each sensor generating a signal indicative of a temperature proximate the temperature sensor; and a controller coupled to the heaters, the fan, and the two temperature sensors, and configured to control a temperature of the circumferential wall of the drum to a set point, the controller activating at least one of the heaters in response to a signal from at least one of the temperature sensors indicating a temperature below a first predetermined temperature threshold, and operating the fan at one of at least three speeds in response to a predetermined relationship between the two temperature signals generated by the temperature sensors and a second predetermined threshold.