Image forming apparatus

摘要

An image forming apparatus has a reciprocatingly movable member for forming an image on a record medium. The reciprocatingly movable member is moved and set to a predetermined home position before a first image is formed. A sensor is associated with the moving and setting operation of the reciprocatingly movable member. An error is detected if the sensor does not sense within a predetermined time which is clocked in synchronism with a control means.