Abstract: 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 T.sub.1 during a copy stand-by period, to set temperature T.sub.2 lower than said set temperature T.sub.

Abstract: A blade cleaning apparatus for an electrophotographic reproducing machine including a cleaning apparatus with a system for cyclically separating a doctor blade from an imaging surface, and a blade vibrator for applying vibration to the doctor blade when it is separated from the surface.

Abstract: In an electrostatographic copying system wherein an image on an initial image support is transferred to a copy sheet, particularly by a transfer corona generator assisted by an auxiliary transfer corona generator applying pre-transfer charges to the initial image support, opposing conductive rollers measure the conductivity of each copy sheet prior to transfer and through a control circuit vary the voltages applied to both the transfer corona generator and the auxiliary transfer corona generator means accordingly. A relay switching system is disclosed automatically selecting between AC and two levels of DC transfer voltages in response to four different copy sheet humidity conditions to optimize the image transfer.

Abstract: A copying apparatus wherein the cleaning unit of the apparatus includes a blade and a collecting roller. The cleaning unit is arranged for movement toward and away from the imaging surface. Apparatus are provided for continuing the rotation of the collecting roller after the copying apparatus has stopped and in response to the movement of the collecting roll and blade away from the imaging surface.

Abstract: Used carrier particles having combustible resinous material on the surface of the core are treated by heating the particles in a fluidized condition to a temperature such as to ignite and burn off the resinous material therefrom.

Abstract: A method and apparatus is disclosed for synchronizing copy substrate positioning with an image position on a photoreceptor in an electrostatic copier that includes primary rollers which drive intermittently at a slower speed than copier process speed while feeding a copy substrate to the photoreceptor. Secondary rollers which are located between the primary rollers and the photoreceptor drive the copy substrate continuously at the process speed. After the copy substrate enters the secondary rollers, the primary rollers stop driving and allow the copy substrate to continue in travel by the driving force of the secondary rollers in synchronism with the image on the photoreceptor.