초록 ▼

A contact heat fixing apparatus comprising heat roll 1 having metal core 3 coated with heat resistant toner releasing material 4 on the surface thereof and provided with a heating element to the inside thereof. Temperature control circuit A comprising detection circuit 15 for the detection of the su

A contact heat fixing apparatus comprising heat roll 1 having metal core 3 coated with heat resistant toner releasing material 4 on the surface thereof and provided with a heating element to the inside thereof. Temperature control circuit A comprising detection circuit 15 for the detection of the surface temperature of heat roll 1, comparison circuit 16 for comparing the level of a signal issued from said detection circuit 15 with that of a reference signal, pulse generation circuit 17 for converting the signal produced from said comparison circuit 16 into a pulse and an alternating current power source 12 whose electric power to be supplied to said heating element 11 is controlled by the signal from said pulse generation circuit, and switching circuit B for applying, to said temperature control circuit A, control signals which control the surface temperature of said heat roll 1 to set temperature T1 during a copy stand-by period, to set temperature T2 lower than said set temperature T1 during copy operation after a certain period from the start of copy, and again to set temperature T1 after another certain period from the completion of copy operation.

대표청구항 ▼

Fuser apparatus for fixing toner images on substrate material, said apparatus comprising: first and second roll members; a heating element disposed internally in one of said members and a source of energy therefor; means for controlling the surface temperature of said roll first during a standby mod

Fuser apparatus for fixing toner images on substrate material, said apparatus comprising: first and second roll members; a heating element disposed internally in one of said members and a source of energy therefor; means for controlling the surface temperature of said roll first during a standby mode followed by a fusing mode and then a standby mode again; said control means for controlling said surface temperature during a standby mode controlling it at a first temperature level and during said fusing mode at a second temperature level which is lower than said first temperature level; means for delaying control at said second temperature after termination of said standby mode and for delaying control at said first temperature after termination of said fusing mode.