Abstract: A control circuit executes voltage adjustment processing of adjusting a voltage output from a transfer power source so that a current detected by a detection circuit becomes a predetermined current value. The voltage adjustment processing is executed before a toner image is transferred from at least one of a first image bearing member and a second image bearing member to an intermediate transfer belt. A processor determines whether the second transfer member is in a state of contact or is in a state of separation on the basis of behavior of the current detected by the detection circuit in a period in which the control circuit is executing the voltage adjustment processing.

Abstract: A printed circuit board comprises a first mounting surface, a second mounting surface, and a piezoelectric transformer. The piezoelectric transformer has a piezoelectric substance, external electrodes, and a frame substrate. The second mounting surface has a projection region. There is a first region from a first location, where an end portion further from the output electrode out of end portions of the input electrode is projected onto the second mounting surface in the projection region, to a second location, where an end portion closer to the output electrode out of the end portions of the input electrode is projected onto the second mounting surface, the first region being a mounting allowed region where an electronic component is mounted.

Abstract: A control circuit executes voltage adjustment processing of adjusting a voltage output from a transfer power source so that ae current detected by a detection circuit becomes a predetermined current value. The voltage adjustment processing is executed before a toner image is transferred from at least one of a first image bearing member and a second image bearing member to an intermediate transfer belt. A processor determines whether the second transfer member is in a state of contact or is in a state of separation on the basis of behavior of the current detected by the detection circuit in a period in which the control circuit is executing the voltage adjustment processing.

Abstract: A controller can select and execute a full color mode of performing image formation in a first state in which each primary transfer member is in contact with an intermediate transfer belt, and a monochrome mode of performing image formation in a second state in which only a primary transfer member is in contact with the intermediate transfer belt. The controller determines which state of the first state and the second state is formed, based on a detection result obtained by a current detection circuit when a photosensitive drum is charged by a charging roller, and voltage is applied to the primary transfer member from a primary transfer power source.

Abstract: A printed circuit board comprises a first mounting surface, a second mounting surface, and a piezoelectric transformer. The piezoelectric transformer has a piezoelectric substance, external electrodes, and a frame substrate. The second mounting surface has a projection region. There is a first region from a first location, where an end portion further from the output electrode out of end portions of the input electrode is projected onto the second mounting surface in the projection region, to a second location, where an end portion closer to the output electrode out of the end portions of the input electrode is projected onto the second mounting surface, the first region being a mounting allowed region where an electronic component is mounted.

Abstract: A controller can select and execute a full color mode of performing image formation in a first state in which each primary transfer member is in contact with an intermediate transfer belt, and a monochrome mode of performing image formation in a second state in which only a primary transfer member is in contact with the intermediate transfer belt. The controller determines which state of the first state and the second state is formed, based on a detection result obtained by a current detection circuit when a photosensitive drum is charged by a charging roller, and voltage is applied to the primary transfer member from a primary transfer power source.

Abstract: A printed circuit board comprises a first mounting surface, a second mounting surface, and a piezoelectric transformer. The piezoelectric transformer has a piezoelectric substance, external electrodes, and a frame substrate. The second mounting surface has a projection region. There is a first region from a first location, where an end portion further from the output electrode out of end portions of the input electrode is projected onto the second mounting surface in the projection region, to a second location, where an end portion closer to the output electrode out of the end portions of the input electrode is projected onto the second mounting surface, the first region being a mounting allowed region where an electronic component is mounted.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective image forming stations.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective stations.

Abstract: The image forming apparatus includes a photosensitive drum, an intermediate transfer belt, a secondary transfer roller, a secondary transfer power supply, an opposing roller through which a current flows through the intermediate transfer belt when the voltage is applied to the secondary transfer roller by the secondary transfer power supply, metal rollers electrically connected to the opposing roller and contacting an inner peripheral surface of the intermediate transfer belt in vicinities of the photosensitive drums, a current restriction circuit connected to a path of a current flowing from the opposing roller to the metal rollers when the voltage is applied to the secondary transfer roller by the secondary transfer power supply, the current restriction circuit configured to restrict the current from the opposing roller to the metal rollers to a predetermined current.

Abstract: The power supply apparatus is configured to detect the output voltage of a piezoelectric transformer and controls the frequency of a pulse signal to drive the piezoelectric transformer based on the detected output voltage and a preset target voltage so as to perform feedback control of the output voltage of the piezoelectric transformer, the gain when performing the feedback control is switched in accordance with the target voltage.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective image forming stations.

Abstract: A printed circuit board comprises a first mounting surface, a second mounting surface, and a piezoelectric transformer. The piezoelectric transformer has a piezoelectric substance, external electrodes, and a frame substrate. The second mounting surface has a projection region. There is a first region from a first location, where an end portion further from the output electrode out of end portions of the input electrode is projected onto the second mounting surface in the projection region, to a second location, where an end portion closer to the output electrode out of the end portions of the input electrode is projected onto the second mounting surface, the first region being a mounting allowed region where an electronic component is mounted.

Abstract: The image forming apparatus includes a photosensitive drum, an intermediate transfer belt, a secondary transfer roller, a secondary transfer power supply, an opposing roller through which a current flows through the intermediate transfer belt when the voltage is applied to the secondary transfer roller by the secondary transfer power supply, metal rollers electrically connected to the opposing roller and contacting an inner peripheral surface of the intermediate transfer belt in vicinities of the photosensitive drums, a current restriction circuit connected to a path of a current flowing from the opposing roller to the metal rollers when the voltage is applied to the secondary transfer roller by the secondary transfer power supply, the current restriction circuit configured to restrict the current from the opposing roller to the metal rollers to a predetermined current.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective stations.

Abstract: An imaging forming apparatus includes a positive high-voltage circuit that generates voltage having a positive polarity, a negative high-voltage circuit connected in series with the positive high-voltage circuit and generates voltage having a negative polarity, a transfer roller to which the voltage generated by the positive high-voltage circuit or the negative high-voltage circuit is supplied, neutralizing pins to which the voltage generated by the negative high-voltage circuit is supplied, a current detection circuit that detects current flowing into the transfer roller, and a diode connected between the transfer roller and the neutralizing pins and that separates a path for the current flowing into the transfer roller and a path for current flowing into the neutralizing pins from each other.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective image forming stations.

Abstract: An imaging forming apparatus includes a positive high-voltage circuit that generates voltage having a positive polarity, a negative high-voltage circuit connected in series with the positive high-voltage circuit and generates voltage having a negative polarity, a transfer roller to which the voltage generated by the positive high-voltage circuit or the negative high-voltage circuit is supplied, neutralizing pins to which the voltage generated by the negative high-voltage circuit is supplied, a current detection circuit that detects current flowing into the transfer roller, and a diode connected between the transfer roller and the neutralizing pins and that separates a path for the current flowing into the transfer roller and a path for current flowing into the neutralizing pins from each other.

Abstract: The power supply apparatus is configured to detect the output voltage of a piezoelectric transformer and controls the frequency of a pulse signal to drive the piezoelectric transformer based on the detected output voltage and a preset target voltage so as to perform feedback control of the output voltage of the piezoelectric transformer, the gain when performing the feedback control is switched in accordance with the target voltage.

Abstract: A voltage maintenance element is connected to a contact member that contacts a primary transfer surface area of an intermediate transfer belt to which toner images are transferred from a plurality of image carriers between stretch members, in such a way as to prevent the electric potential of the intermediate transfer belt from varying between respective stations.