Image forming apparatus

A method for image forming, the method comprising:

• preparing an image forming apparatus, the image forming apparatus comprising:
• an optical scanning unit provided with a polygon motor, the optical scanning unit being configured to generate a first scanning beam and a second scanning beam;
• a first reflecting mirror having a first end and a second end in a length direction of the first reflecting mirror, the first end being fixedly supported, the second end being movably supported, the first reflecting mirror being configured to guide the first scanning beam to a first scan position;
• a second reflecting mirror having a first end and a second end in a length direction of the second reflecting mirror, the first end being fixedly supported, the second end being movably supported, the second reflecting mirror being configured to guide the second scanning beam to a second scan position;
• a first photoconductive drum configured to forma first latent image by the first scanning beam, the first scanning beam scanning at the first scan position;
• a second photoconductive drum configured to form a second latent image by the second scanning beam, the second scanning beam scanning at the second scan position;
• an image forming unit configured to form a first toner image and a second toner image by developing each of the first latent image and the second latent image with a toner and to form an image on a sheet by transferring the first toner image and the second tone image to the sheet;
• a first cam configured to movably support the second end of the first reflecting mirror;
• a second cam configured to movably support the second end of the second reflecting mirror;
• a first motor configured to rotate in a first direction and in a second direction, a rotational direction of the first motor being switched between the first direction and the second direction;
• a first gear train configured to be capable of transmitting a drive force from the first motor to the first cam and the second cam;
• and a first clutch provided in the first gear train, the first clutch being configured to allow the first cam to move by transmission of the drive force of the first motor and to allow the second cam to stop by non-transmission of the drive force in a case where the first motor rotates in the first direction, the first clutch being configured to allow the second cam to move by transmission of the drive force and to allow the first cam to stop by non-transmission of the drive force in a case where the first motor rotates in the second direction;
• adjusting a position of at least one of the second end of the first reflecting mirror and the second end of the second reflecting mirror by driving the first motor;
• and
• forming an image on a sheet by using the image forming apparatus.