FUSER ROLL TEMPERATURE PROFILE UNIFORMITY USING HEAT PIPE
Original Publication Date: 1987-Aug-31
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
In an electrophotographic printing machine, a fuser roll is frequently employed to fuse the toner image to the copy sheet. However, the lateral heat distribution of the fuser roll is not uniform. This problem has been exacerbated, in recent years, by the use of lower thermal conductivity cores, edge registration, and an increased range of paper sizes. A cylindrical heat pipe in rolling contact with the fuser roll redistributes the heat laterally A suitable heat pipe is a copper tube sealed with end plugs under vacuum. A fluid, such as deionized water or methanol, is placed in the tube.' A coil spring is located in the tube. The spring redistributes the fluid after it condenses. The heat pipe is positioned against the fuser roll and rotated frictionally by the fuser roll. When the fuser roll is non-uniformly heated or has a small size copy sheet passing therethrough, the non-uniformity in temperature is equalized continuously by the heat pipe. This improves copy quality and extends fuser roll life.