Abstract: A brushless motor device including: a rotor; a stator including a first coil, a second coil and a third coil, first ends of which are Y-connected to each other; a motor driver including an inverter circuit including switching elements and configured to: switch ON and OFF states of each switching element of the inverter circuit, wherein by switching the ON and OFF states of each switching element of the inverter circuit, the motor driver is configured to switch an energization time period from a first time period in which current is caused to flow from the first coil to the third coil to a second time period in which current is caused to flow from the second coil to the third coil and set both voltages of second ends of the second coil and the third coil to a power supply voltage during the second time period.

Abstract: A brushless motor device including: a rotor; a stator including a first coil, a second coil and a third coil, first ends of which are Y-connected to each other; a motor driver including an inverter circuit including switching elements and configured to: switch ON and OFF states of each switching element of the inverter circuit, wherein by switching the ON and OFF states of each switching element of the inverter circuit, the motor driver is configured to switch an energization time period from a first time period in which current is caused to flow from the first coil to the third coil to a second time period in which current is caused to flow from the second coil to the third coil and set both voltages of second ends of the second coil and the third coil to a power supply voltage during the second time period.

Abstract: An image forming apparatus includes a belt, a cling unit, an application unit and a controller. The controller when a leading end portion of the belt where a leading end of a sheet in a conveying direction is disposed is present at a facing position where the belt and the cling unit face each other, controls the application unit to apply a clinging bias to the cling unit for supplying electric charge to the leading end portion, and when an intermediate portion of the belt disposed between the leading end portion and a trailing end portion thereof where a trailing end of the sheet is disposed is present at a facing position, reduces the clinging bias to be less than the clinging bias when the leading end portion is present at the facing position.

Abstract: An image forming apparatus, comprising: an attachment unit to which a load for image formation is attached; an applying circuit configured to apply an applying voltage to the load; a voltage detection circuit configured to detect the applying voltage; a current detection unit configured to detect a load current; and a control device, wherein the control device is configured to: subject the applying circuit to constant current control in accordance with a detected value of the current detection unit so that the load current becomes a target current; and switch to a constant voltage control by which the applying voltage is controlled to become a target voltage when an absolute value of the load current is smaller than a determination value and an absolute value of the applying voltage is larger than or equal to a threshold during execution of the constant current control.

Abstract: An image forming apparatus includes a belt, a cling unit, an application unit and a controller. The controller when a leading end portion of the belt where a leading end of a sheet in a conveying direction is disposed is present at a facing position where the belt and the cling unit face each other, controls the application unit to apply a clinging bias to the cling unit for supplying electric charge to the leading end portion, and when an intermediate portion of the belt disposed between the leading end portion and a trailing end portion thereof where a trailing end of the sheet is disposed is present at a facing position, reduces the clinging bias to be less than the clinging bias when the leading end portion is present at the facing position.

Abstract: An image forming apparatus, comprising: a charge voltage application circuit configured to be connected to a plurality of chargers in a process cartridge and to apply a voltage to the plurality of chargers; a current detection unit configured to detect a current flowing through each of the plurality of chargers; and a controller. The controller judges that the process cartridge is not attached to the image forming apparatus when the current smaller than a first threshold is detected by the current detection unit in a state where the charge voltage application circuit generates a predetermined voltage.

Abstract: An image forming apparatus, comprising: an attachment unit to which a load for image formation is attached; an applying circuit configured to apply an applying voltage to the load; a voltage detection circuit configured to detect the applying voltage; a current detection unit configured to detect a load current; and a control device, wherein the control device is configured to: subject the applying circuit to constant current control in accordance with a detected value of the current detection unit so that the load current becomes a target current; and switch to a constant voltage control by which the applying voltage is controlled to become a target voltage when an absolute value of the load current is smaller than a determination value and an absolute value of the applying voltage is larger than or equal to a threshold during execution of the constant current control.

Abstract: An image forming device, comprising: at least one photosensitive body; scorotron chargers that charge the at least one photosensitive body; a charge voltage applying circuit to which the scorotron chargers are commonly connected, the charge voltage applying circuit being configured to apply a voltage to the scorotron chargers; wires respectively provided for the scorotron chargers; grid electrodes respectively provided for the scorotron chargers; a current detection unit configured to detect a grid current of each of the grid electrodes; and a grid current control unit configured to execute a constant-current control for a maximum grid current which is a maximum of grid currents flowing through the grid electrodes so that the maximum grid current is kept at a first threshold larger than or equal to a reference value by adjusting an output of the charge voltage applying circuit.

Abstract: An image forming apparatus, comprising: a charge voltage application circuit configured to be connected to a plurality of chargers in a process cartridge and to apply a voltage to the plurality of chargers; a current detection unit configured to detect a current flowing through each of the plurality of chargers; and a controller. The controller judges that the process cartridge is not attached to the image forming apparatus when the current smaller than a first threshold is detected by the current detection unit in a state where the charge voltage application circuit generates a predetermined voltage.