Browse Prior Art Database

RADIATION TRANSFER FUSER TEMPERATURE SENSOR

IP.com Disclosure Number: IPCOM000024534D
Original Publication Date: 1980-Dec-31
Included in the Prior Art Database: 2004-Apr-02
Document File: 2 page(s) / 83K

Publishing Venue

Xerox Disclosure Journal

Abstract

In order to measure the temperature of the heated pressure fusing roller of a xerographic copier-duplicator device, it is common practice to use a non-contacting sensor instead of a contacting sensor. Typically, thermistors or other devices are used wherein the electrical properties of the device are a function of their temperature. In general, with such devices the mode of energy transfer is by thermal conduction through the separating air layer, and thermal radiation effects are minimized. A major disadvantage of this approach is that the output of the thermal sensing device is a very sensitive function of the spacing between the sensors and the heated surface whose temperature is to be measured. In addition, the time constant of the device response is long.

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RADIATION TRANSFER FUSER TEMP- ERATURE SENSOR
D. E. Paraskevopoulos

Proposed Classification

Int. Cl. G03g 15/00


U.S. Cl. 355/3

In order to measure the temperature of the heated pressure fusing roller of a xerographic copier-duplicator device, it is common practice to use a non- contacting sensor instead of a contacting sensor. Typically, thermistors or other devices are used wherein the electrical properties of the device are a function of their temperature. In general, with such devices the mode of energy transfer is by thermal conduction through the separating air layer, and thermal radiation effects are minimized. A major disadvantage of this approach is that the output of the thermal sensing device is a very sensitive function of the spacing between the sensors and the heated surface whose temperature is to be measured. In addition, the time constant of the device response is long.

The limitations of this method of temperature measurement are largely overcome by the use of the method described in this disclosure and illustrated in Figure 1. The device features low sensitivity to spacing variations and fast response. Thermistor or other temperature sensor 1 is mounted in non-reflective housing 2, to which is attached conical structure 3 extending to close proximity with heated surface 4 whose temperature is to be measured. The cone provides high reflectivity at thermal wavelengths, low thermal conductivity and low thermal capacity. A possible material for the...