Abstract: An image forming apparatus includes an image forming unit for forming an image on a sheet, a first conveying unit for conveying a sheet along a first conveying path toward the image forming unit, a second conveying unit for conveying a sheet along a second conveying path toward the image forming unit, a first detection unit for detecting the sheet remaining in the first conveying path, a second detection unit for detecting the sheet remaining in the second conveying path, and a control unit for discharging the sheets in the first and second conveying paths from the image forming apparatus by simultaneously driving the first and second conveying units whether or not the sheets in the first and second conveying paths are conveyed superposed in the image forming unit, in accordance with the detection of the remaining sheets by the first and second detection units, before the image forming unit starts image formation.

Abstract: An apparatus for generating a laser beam modulated on the basis of an information signal, which comprises a circuit for generating a first information signal, a circuit for generating a second information signal, independent of the first information signal, a circuit for driving a semiconductor laser on the basis of the first and the second information signals, wherein the driving circuit comprises first and second switching elements which operate supplementarily with each other, one of the first and second switching elements switches a drive current to the semiconductor laser, and wherein the first information signal is provided into a control terminal of the first switching element and the second information signal is provided into a control terminal of the second switching element.

Abstract: An image forming apparatus includes recording structure for recording an image on a recording medium, first and second conveying structures for conveying the recording medium to the recording structure, detecting structure for detecting a plurality of multi-fed recording media fed by the conveying structure, and control structure for controlling the first and second conveying structures so that an image is recorded on a recording medium separated from the multi-fed recording media and detected by the detecting structure or discharged from the image forming apparatus.

Abstract: A temperature control device for controlling a surface temperature of a member to be heated at a predetermined temperature includes a detector for detecting the surface temperature, and a control unit for controlling current supply for a heating source for heating the member to be heated so that a result of detection by the detector is maintained at a predetermined value. The control unit controls a time of current supply for the heating source during a constant temperature control according to data relating to peak temperatures of the surface temperature during the constant temperature control.

Abstract: In a power supply circuit for a motor in which a power source line can be opened and closed by a first opening-closing device, a construction is adopted which has a electrically controllable second opening-closing device connected in parallel to the first opening-closing device, a comparator for comparing the voltage of the motor load side with a predetermined value, a controller for controlling the opening and closing of the second opening-closing device on the basis of a signal from the comparator, and a current limiter device provided in parallel to the second opening-closing device, whereby a rush current when the first opening-closing device is closed can be suppressed to thereby prevent the fluctuation of the source voltage and the deterioration of the contacts of the first opening-closing device.

Abstract: An image forming apparatus includes an image forming device for forming an image on a recording material, the image forming device including an image bearing member, a movable charging member for charging the image bearing member and a power source for supplying electric power to the charging member; a constant current controller for supplying the charging member with a predetermined constant level of electric current; and a second controller for controlling an image forming condition by the image forming device on the basis of plural voltage provided at different points of time during a constant current control operation with the same constant current level by the constant current controller.

Abstract: A positioning apparatus for positioning a reciprocally movable member, such as a guide member for a sheet of recording paper, between a reference position and a predetermined position. The apparatus includes a detector for detecting that the movable member is in the proximity of the reference position, and a counter for counting the amount by which the movable member is shifted while the detector is detecting that the movable member is in the proximity of the reference position. A controller stores the value counted by the counter, and controls drive of the movable member when the movable member is being returned to the reference position based on the count in the counter and the stored count value. A second counter may be provided to count the amount by which the movable member is shifted from the reference position to the predetermined position.