Image forming apparatus controlling image formation based on a zero-crossing detection signal

An image forming apparatus comprising a power supply unit configured to generate a DC voltage from an AC voltage and supply the DC voltage to a load, the image forming apparatus configured to perform image formation on a recording material,

• the image forming apparatus including a first control unit configured to control the image formation on the recording material,
• the power supply unit including:
• a second control unit configured to control a voltage generation unit that generates the DC voltage from the AC voltage input from an AC power supply,
• a zero-crossing detection unit configured to detect a zero-crossing timing of the AC voltage according to the AC voltage input, and to output a zero-crossing detection signal, and
• a transmission unit configured to transmit the zero-crossing detection signal output from the zero-crossing detection unit to the first control unit,
• wherein the second control unit is configured to obtain information related to a primary side of the voltage generation unit and convert the information related to the primary side to a corresponding signal with a shorter cycle than a cycle of the zero-crossing detection signal, and
• wherein the second control unit is configured to superpose the corresponding signal on the zero-crossing detection signal, and the transmission unit is configured to transmit the zero-crossing detection signal to the first control unit.