PURPOSE: To optionally use a reflector shaped with high reflection efficiency and to remove dangerousness rolling in recording paper at the operation of the titled device by forming the reflector for reflecting heat rays to a paper carrying course, and a shutter member positioned to interrupt a radiation heat source from the paper carrying course.

CONSTITUTION: Two squeezing shafts 55, 56 arranged close to the reflector 5 hold a shielding plate 52 between them, and when the shielding plate is displaced from its holding position to the lower part of a heater 4 at an abnormal time, the shafts 55, 56 are arranged on respective position where the shafts 55, 56 do not interfere in the displacing operation of the shielding plate 52. On the other hand, an upper paper guide 13 arranged on the carrying course 3 of recording paper P under the heater 4 prevents the recording paper curled or folded or wrinkled due to jam from direct contact with the heater 4 or the reflector 5 or enter close to these parts.