Abstract: An image forming apparatus includes two power cords (70, 80), a plurality of processing sections, a relay (91) and a control section (87). The relay (91) is switched between a conducting state where the two power cords (70, 80) can provide a bilateral supply of power between each other and a cut-off state where they cannot. The control section (87) stores an order of priority for the plurality of processing sections, switches the relay (91) from the cut-off state to the conducting state when a supply of power through either one power cord of the two power cords (70, 80) is cut off, and, by selecting a processing section sequentially according to the order of priority, causes load instruments included in the processing section currently selected to be driven while causing load instruments other than specified load instruments among load instruments included in processing sections currently not selected to stop.

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and the second photoconductor groups respectively to rotate the photoconductors thereof, wherein the rotational phases of the first photoconductor group and the second photoconductor group are adjusted to be matched therebetween; and the first and the second drive control sections control so that predetermined profile of a target speed is applied to the first and second photoconductor groups wherein, in the target-speed profile, the first photoconductor group starts rotating after a elapse of a predetermined startup delay time from the second photoconductor group starts rotating, and both groups end at a same final speed predetermined for full-color image formation, wherein the startup delay time is predetermined based on measurements of times needed for each of the first and the second photo

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and the second photoconductor groups respectively to rotate the photoconductors thereof, wherein the rotational phases of the first photoconductor group and the second photoconductor group are adjusted to be matched therebetween; and the first and the second drive control sections control so that the first and the second photoconductor groups are driven simultaneously with an equal target speed during a formation of a image, wherein an initial drive speed is lower than a predetermined speed for image-formation, and after the first and the second photoconductor groups reaches the initial drive speed, the target speed is changed from the initial drive speed to the speed for image-formation.

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and second photoconductor groups respectively to rotate the photoconductors thereof, and a deceleration measuring section for measuring respective degrees of deceleration when the first and second photoconductor groups rotate under their own inertias with a drive thereof being stopped, wherein the rotational phases of the first photoconductor group and the second photoconductor group are adjusted to be matched therebetween; and the first and second drive control sections determine a control pattern for decelerating so that a degree of deceleration to be applied at the stage of stopping drive of the first and second photoconductor groups become equal to or slower than the slowest one among the degrees of deceleration being measured.

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and the second photoconductor groups respectively to rotate the photoconductors thereof, wherein the rotational phases of the first photoconductor group and the second photoconductor group are adjusted to be matched therebetween; and the first and the second drive control sections control so that predetermined profile of a target speed is applied to the first and second photoconductor groups wherein, in the target-speed profile, the first photoconductor group starts rotating after a elapse of a predetermined startup delay time from the second photoconductor group starts rotating, and both groups end at a same final speed predetermined for full-color image formation, wherein the startup delay time is predetermined based on measurements of times needed for each of the first and the second photo

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and second photoconductor groups respectively to rotate the photoconductors thereof, and a deceleration measuring section for measuring respective degrees of deceleration when the first and second photoconductor groups rotate under their own inertias with a drive thereof being stopped, wherein the rotational phases of the first photoconductor group and the second photoconductor groups are adjusted to be matched therebetween; and the first and second drive control sections determine a control pattern for decelerating so that a degree of deceleration to be applied at the stage of stopping drive of the first and second photoconductor groups become equal to or slower than the slowest one among the degrees of deceleration being measured.

Abstract: An image forming apparatus including: a first and a second photoconductor groups constituted of one or more photoconductors respectively; a first and a second drive control sections for controlling the drive of the first and the second photoconductor groups respectively to rotate the photoconductors thereof, wherein the rotational phases of the first photoconductor group and the second photoconductor group are adjusted to be matched therebetween; and the first and the second drive control sections control so that the first and the second photoconductor groups are driven simultaneously with an equal target speed during a formation of a image, wherein an initial drive speed is lower than a predetermined speed for image-formation, and after the first and the second photoconductor groups reaches the initial drive speed, the target speed is changed from the initial drive speed to the speed for image-formation.