| 主权项 |
1. A development device including: a development roller that is disposed opposite to an image carrier on which an electrostatic latent image is formed and that supplies toner to the image carrier in an area opposing the image carrier; a toner supply roller that is disposed opposite to the development roller and supplies toner to the development roller in an area opposing the development roller; a restricting blade disposed opposite to the toner supply roller at a first predetermined distance; and a casing that houses the development roller, the toner supply roller, and the restricting blade, wherein
the casing includes an internal wall opposing the development roller between the restricting blade and the image carrier, the development device comprising: a film member disposed at a second predetermined distance from a top surface of the internal wall, the film member having flexibility and capable of vibrating in a direction in which the film member moves closer to or apart from the internal wall; a biasing member that is connected to at least one end in a longitudinal direction of the film member and provides tension to the film member; and an idler gear that is a helical gear, wherein the idler gear includes at least one projection, the idler gear is reciprocally movable along a rotational axis of the idler gear between a first position and a second position, the first position is a position where the projection is apart from an end edge of the film member in response to a rotation of the toner supply roller when image formation is performed, the second position is a position where the projection overlaps with the end edge of the film member in response to a reverse rotation of the toner supply roller when image formation is not performed, and the projection causes the film member to vibrate by intermittently coming into contact with the end edge of the film member along with the rotation of the idler gear positioned at the second position. |
