Abstract: An image forming apparatus spools normal print requests received from external equipment as normal print jobs which are sequentially executed by a printer, spools a private print request received from an external equipment in a spooler as a private print job executed by a printer in response to an instruction by a user who has requested the private print, and changes a normal print job in an execution waiting state of the user which is spooled in the spooler to a private print job of the user in response to a request from the user authenticated by a user authenticating portion.

Abstract: A fixing device of the invention detects a temperature of plural positions of a heat roller by a multiple non-contact temperature sensor at the same time and controls the temperature of plural heat source members. The non-contact temperature sensor and a contact temperature sensor detect the temperature of the same position. According to the detection result, maintenance is performed or a temperature conversion table is corrected, the non-contact temperature sensor is maintained with high precision, and the heat roller is controlled the temperature with high precision.

Abstract: A cleaning device in an image forming apparatus, which performs cleaning, includes a roll-shaped electrically conductive brush grounded via a varistor (non-linear resistor element), a flicker metal rod which is put in pressure contact with the electrically conductive brush and connected to have a potential equal to a potential of the electrically conductive brush, and a cleaning blade formed of an elastic material.

Abstract: The present invention provides a fixing device and a digital photocopier which can shorten the time from an instruction of starting image formation to end of fixing. The fixing device is provided in a cylinder made of metal and having a small thickness, and includes a magnetic excitation coil. When the power source is turned on, all the electric power defined by subtracting an electric power amount consumed by components other than the fixing device is supplied to the magnetic excitation coil to perform heating. As the structural components of the photocopier and auxiliary devices added to the photocopier operate, the electric power defined by subtracting, from the maximum input electric power, the electric power consumed by the structural components of the photocopier and the auxiliary devices is supplied to perform heating. In this manner, the heat roller of the fixing device is heated, in a short time, to a temperature which enables fixing, so that the time required for first copying can be shortened.