Abstract: A density controlling method for controlling the density of toner applied to the surface of a photosensitive drum of a photocopying machine is disclosed herein. A small area of the drum is irridated with light, and toner is applied thereon. A photo-transistor sensor senses the density of the toner, and a signal produced by the sensor is compared to a reference signal indicative of optimal toner density. The difference signal is then applied through a CPU to control both the bias voltage of the developing system and the speed of the toner motor.

Abstract: An automatic exposure control method for a photocopying machine is disclosed herein. A sensor is periodically interposed in the light path of the photocopier, which samples the intensity of the light produced by the light producing system. This intensity is compared with a signal representative of the optimum light intensity for the photosensitive drum, and the light source is controlled by inputting the resulting intensity control signal to a voltage regulated light source control device.

Abstract: For automatically gathering the data necessary to quantify and qualify the usage of a facsimile transceiver, there is a data collecting device having a pair of electromechanical counters which are driven by separate capacitive-type pulse generators in response to a DC control current for the transceiver to register running counts corresponding to respective ones of (1) the total number of operating cycles on the transceiver, (2) the accumulated number of cycles devoted to operation of the transceiver in a transmit mode, and (3) the accumulated number of cycles devoted to operation of the transceiver in a receive mode.