Abstract: An image forming apparatus for forming an image with an electrophotographic process, that includes: a power source; a first drive unit having a capacitative load and driving each part of the apparatus; a second drive unit having a capacitative load and driving each part of the apparatus; and a power supply control circuit that is provided on a power supply path between the power source and the second drive unit, that switches whether or not electric power is supplied to the second drive unit. The power supply control circuit includes: a field-effect transistor with its source connected to the power source side of the power supply path, and its drain connected to the second drive unit side of the power supply path; a first resistive element connected between the field-effect transistor's gate and its source; a second resistive element and a capacitative element that are connected in parallel with the first resistive element, and connected with each other in series between the gate and the source.

Abstract: An image forming system includes a first device having a power unit that generates a drive voltage and an image forming portion, and a second device for controlling the image forming portion. The power unit generates a first drive voltage as the drive voltage and a second drive voltage higher than the first drive voltage, and the second device includes a voltage supply control portion that controls whether or not the second drive voltage is supplied to the second device.

Abstract: An image forming apparatus which repeats image create/transfer processing while rotating a photosensitive member and a transfer medium in a sub scanning direction and thereafter transferring the toner image onto the transfer medium, for a plurality of toner colors which are different from each other, to thereby lay toner images in respective toner colors over each other on the transfer medium and accordingly form a color image. The apparatus corrects transfer start positions of toner image in at least one or more toner colors out of the plurality of toner colors based on a registration control amount which is necessary to correct relative registration deviations among toner images on the transfer medium.

Abstract: Power transmission members (91), which transmit rotational drive force from a drive source (81), such as a motor, to an intermediate transfer drum (41D) is elastically deformed due to a load change which is generated as a cleaning part (49) contacts and moves away from the intermediate transfer drum (41D). Registration control amounts (Ra, Rb and Rc) attributed to the elastic deformation are obtained in advance. Transfer start positions for toner images in at least one or more toner colors out of four toner colors are corrected based on the registration control amounts (Ra, Rb and Rc), whereby registration deviations are suppressed to minimum and a high-quality color image is obtained.

Abstract: An image forming apparatus for forming an image with an electrophotographic process, that includes: a power source; a first drive unit having a capacitative load and driving each part of the apparatus; a second drive unit having a capacitative load and driving each part of the apparatus; and a power supply control circuit that is provided on a power supply path between the power source and the second drive unit, that switches whether or not electric power is supplied to the second drive unit. The power supply control circuit includes: a field-effect transistor with its source connected to the power source side of the power supply path, and its drain connected to the second drive unit side of the power supply path; a first resistive element connected between the field-effect transistor's gate and its source; a second resistive element and a capacitative element that are connected in parallel with the first resistive element, and connected with each other in series between the gate and the source.

Abstract: Power transmission members (91), which transmit rotational drive force from a drive source (81), such as a motor, to an intermediate transfer drum (41D) is elastically deformed due to a load change which is generated as a cleaning part (49) contacts and moves away from the intermediate transfer drum (41D). Registration control amounts (Ra, Rb and Rc) attributed to the elastic deformation are obtained in advance. Transfer start positions for toner images in at least one or more toner colors out of four toner colors are corrected based on the registration control amounts (Ra, Rb and Rc), whereby registration deviations are suppressed to minimum and a high-quality color image is obtained.

Abstract: An image forming apparatus includes a main power source, a replaceable unit, a switch and a memory. The main power source includes a first power source which supplies power to a high load unit and a second power source which supplies power to a low load unit. The replaceable unit is used for image formation. The switch switches between an image forming operation mode and a non-image forming operation mode. The memory is supplied with the power from the second power source. Lifetime management information of the replaceable unit is stored in the memory during the image forming operation mode.

Abstract: An image forming apparatus and method that repeats image create/transfer processing, in which serial processing of forming a toner image on a photosensitive member while rotating the photosensitive member and a transfer medium in a sub scanning direction and thereafter transferring the toner image onto the transfer medium, for a plurality of toner colors which are different from each other. The apparatus and method lay toner images in the respective toner colors over each other on said transfer medium and accordingly form a color image. Correcting transfer start positions of toner images in at least one or more toner colors out of the plurality of toner colors is based on a registration control amount which is necessary to correct relative registration deviations among toner images on the transfer medium.

Abstract: Power transmission members (91), which transmit rotational drive force from a drive source (81), such as a motor, to an intermediate transfer drum (41D) is elastically deformed due to a load change which is generated as a cleaning part (49) contacts and moves away from the intermediate transfer drum (41D). Registration control amounts (Ra, Rb and Rc) attributed to the elastic deformation are obtained in advance. Transfer start positions for toner images in at least one or more toner colors out of four toner colors are corrected based on the registration control amounts (Ra, Rb and Rc), whereby registration deviations are suppressed to minimum and a high-quality color image is obtained.

Abstract: Power transmission members which transmit rotational drive force from a drive source such as a motor, to an intermediate transfer drum is elastically deformed due to a load change which is generated as a cleaning part contacts and moves away from the intermediate transfer drum. Registration control amounts (Ra, Rb and Rc) attributed to the elastic deformation are obtained in advance. Transfer start positions for toner images in at least one or more toner colors out of four toner colors are corrected based on the registration control amounts (Ra, Rb and Rc), whereby registration deviations are suppressed to minimum and a high-quality color image is obtained.