Driving apparatus, image forming apparatus, driving method and image forming method

An driving apparatus comprising:

• a plurality of image bearing bodies each of which is rotatable and capable of bearing a latent image and a developer image;
• a belt provided so as to face the image bearing bodies, the belt being rotatable;
• a plurality of image-bearing-body-driving units for rotating the image bearing bodies;
• a belt driving unit for rotating the belt;
• and
• a control unit for controlling the image-bearing-body-driving units and the belt driving unit,
• wherein the control unit causes the image-bearing-body-driving units and the belt driving unit to start rotating the image bearing bodies and the belt so that the image bearing bodies and the belt rotate at a first speed, and
• wherein when the control unit detects that the image bearing bodies and the belt rotate at the first speed, the control unit causes the image-bearing-body-driving units and the belt driving unit to accelerate rotation speeds of the image bearing bodies and the belt to a second speed faster than the first speed.