Patent ID: 6505142
Filing Date: 2003-01-07
Classification: B41J

Abstract:
A drawing apparatus for drawing an image on a recording material comprising:a drum shaped as a cylinder and having a rotary shaft and an outer peripheral surface; driving means for rotating said drum around said rotary shaft; a fixing member provided on the outer peripheral surface of said drum for fixing said recording material to the outer peripheral surface of said drum; a plurality of balance weights provided so as to be movable and fixable along a circumference whose center coincides with said rotary shaft of said drum; position calculation means for calculating positions of said plurality of balance weights for canceling an unbalance force caused by centrifugal forces developed by said fixing member and said recording material at the time of rotating said drum; and unbalance detection means for detecting the presence or absence of an unbalance force caused by the centrifugal forces exerted on said drum, wherein said unbalance detection means comprises driving release means for releasing a driving force of said driving means, to bring said drum into a free state from said driving means, rotation detection means for detecting whether or not said drum is rotated after being brought into a free state by said driving release means, and judgment means for judging the presence or absence of said unbalance force on the basis of the result of the detection by said rotation detection means.