Patent ID: 6459867
Filing Date: 2002-10-01
Classification: G03G

Abstract:
A developing apparatus which performs development by supplying a thin toner layer to an electrostatic latent image on an image carrier, comprising:a cylindrical toner carrier for transferring supplied toner to a development position by rotation of the toner carrier; supply means for supplying toner to an outer peripheral surface of the toner carrier; a layer thickness controlling member for controlling thickness of the supplied toner to within a predetermined value while making slide contact with the outer peripheral surface of the toner carrier; and sealing means for holding the layer thickness controlling member and preventing toner leakage, wherein the layer thickness controlling member is formed of an elastic plate extending in parallel with the toner carrier, and has a bent portion which is convex toward the toner carrier and makes elastic contact with the outer peripheral surface of the toner carrier over a nearly entire length thereof, one end of the layer thickness controlling member in a width direction thereof with respect to the bent portion outwardly extending in a radial direction of the toner carrier, a portion on the other side of the layer thickness controlling member in the width direction thereof extending in a peripheral direction of the toner carrier toward a downstream side of the rotation direction of the toner carrier, and the sealing means consisting of an upstream side sealing member which makes contact with the one end of the layer thickness controlling member from an upstream side of the rotation direction of the toner carrier and a downstream side sealing member which makes contact with the one end of the layer thickness controlling member from a downstream side of the rotation direction of the toner carrier, the one end of the layer thickness controlling member being caught between the upstream side sealing member and the downstream side sealing member so that the layer thickness controlling member is held to be elastically displaceable in the radial direction of the toner carrier.