Abstract: An image forming apparatus comprising a body to be charged, and a central processing unit for processing based on oscillation clock pulses from a crystal oscillator, including a timer for generating a pulse signal having a predetermined period based on the oscillation clock pulses. A charging member performs a charging operation on the body to be charged, and first applying means applies a first AC voltage to the charging member, wherein the first applying means generates the first AC voltage based on a pulse signal from the timer in the central processing unit.

Abstract: A heating apparatus comprising a heating member, energization element for energizing said heating member, a temperature detection member for detecting a temperature of said heating member, a first switching element for turning on/off energization by said energization means on the basis of the temperature detected by said temperature detection member, abnormal current detection element for detecting an abnormal current flowing through said heating member, a second switching element for turning off energization by said energization element, and energization stop member for operating said second switching element to turn off energization.

Abstract: An image recording apparatus operated in synchronism with a vertical synchronization signal from an external device comprises a unit for sending out to the external device a signal indicating a status to accept the vertical synchronization signal, and switching device for switching between a plurality of operation modes related to an elapsed time from the send-out of the signal by the signal sending unit.

Abstract: An image forming apparatus includes: a photosensitive drum; a charging unit which is brought into contact with the drum and charges it; a developing unit for obtaining a visible image from an electrostatic latent image formed on the drum; a charge high voltage generation circuit for supplying an output which is obtained by multiplexing a high AC voltage with a high DC voltage with the charging unit; a development high voltage generation circuit for supplying an output which is obtained by multiplexing a high AC voltage with a high DC voltage to the developing unit; and a sync circuit for synchronizing a high voltage alternating current of the charge high voltage generation circuit and a high voltage alternating current of the development high voltage generation circuit. A ratio of the frequencies of the high voltage alternating currents of the development high voltage generation circuit and the charge high voltage generation circuit is set to an integer.

Abstract: The present invention provides an image forming apparatus with a sheet supply cassette which can contain a plurality of recording members and can be removably mounted within the image forming apparatus, an image forming device for forming an image on the recording member with toner to form a toner image, fixing rollers having a heater for thermally fixing the toner image on the recording member, remaining amount detecter means for detecting the remaining amount of the recording members in the sheet supply cassette or/and a remaining amount of the toner and generating a detection signal, and energization stopping control for stopping the energization of the heater on the basis of the detection signal.

Abstract: An image forming apparatus includes an image forming unit for forming an undeveloped image on a recording material, heating fixing unit for fixing the undeveloped image on the recording material by heating. The heating fixing unit includes a heating member heated by a heater, a temperature detector for detecting a temperature of the heating member, and a current-supply control unit for controlling current supply to the heater so that the temperature detected by the temperature detector is maintained at a predetermined control temperature in a standby state. The apparatus further includes an electric-power reduction unit for reducing or cutting electric power supplied to the heater when an image forming signal is not input for a predetermined time period after the completion of an image forming operation, and a discriminating unit for discriminating the frequency of image forming operations.

Abstract: The present invention provides an image forming apparatus in which the first lead wire which transmits a detection signal indicating the remaining amount of toner in the developing unit into a circuit for comparison with the reference voltage, and the second lead wire are arranged parallel. One end of the second lead wire is connected to the reference voltage generating side and the other end is electrically open.