US 5,537,191 A · Image forming apparatus with toner transport mechanism incorporated therein

Abstract

An endless toner transport which connects a developing device with a cleaning device is disposed so as to pass through these devices in their respective longitudinal directions. The mixing of toner can be enhanced by returning recovered toner to the developing device and by supplying fresh toner to the cleaning device by using the toner transport itself, whereby the reuse of recovered toner and the reduction of the quantity of fresh toner used can be conducted more effectively. In the processes of transporting toner from the developing device to the cleaning device and from the cleaning device to the developing device, toner can effectively be stirred and mixed by utilizing oscillation or the like generated in the endless toner transport which can be in the form of a coil spring so that an additional stirring member is not required, thereby allowing the developing device, and hence the entire image forming apparatus, to be greatly reduced in size.

Claims44

Dependent claims

An image forming apparatus comprising:

electrostatic latent image holding means;
developing means disposed in close proximity to said electrostatic latent image holding means;
cleaning means disposed in close proximity to said electrostatic latent image holding means;
other image forming process means in close proximity to said electrostatic latent image holding means;
an endless toner transport path disposed between said developing means and said cleaning means;
endless toner transport means for transporting toner along said endless toner transport in a toner transport path in a toner transport direction, said endless toner transport means passing through said developing means and said cleaning means in their respective longitudinal directions;
and
toner supply means disposed at a location along said endless toner transport path of said endless toner transport means other than where said developing means and said cleaning means are disposed.

5 more elements

A toner transport mechanism which is disposed between a developing device for supplying toner to a surface of a photosensitive body to develop a latent image on the surface of said photosensitive body to form a toner image, and a cleaning device for removing and recovering residual toner adhering to the surface of said photosensitive body, and which transports residual toner recovered by said cleaning device to said developing device after the toner image formed by said developing device is transferred to a sheet, wherein said toner transport mechanism comprises:

an endless coil spring which is disposed so as to circulate between said cleaning device and said developing device, said coil spring having a natural essentially circular ring shape;
driving means for driving said coil spring;
and
a guide portion for guiding said coil spring driven by said driving means in a driving direction while reforming said coil spring into a substantially quadrangular shape which consists of four corners, and substantially linearly extending portions which are continuous with said corners and which have an arcuate shape swelling outwardly, said guide portion having an open portion which opens a lower portion of said coil spring to said developing device.

1 more element

an endless coil spring which is disposed so as to circulate between said cleaning device and said developing device, said coil spring having a natural essentially circular ring shape;
driving means for driving said coil spring;
and
a guide portion for guiding said coil spring driven by said driving means while reforming said coil spring into a substantially quadrangular shape which consists of four corners, and substantially linearly extending portions which are continuous with said corners and which have an arcuate shape swelling outwardly, at least a face of said corners which slidingly contacts with said coil spring being made of a material having a small friction coefficient, said guide portion having an open portion which opens a lower portion of said coil spring to said developing device.

1 more element

Dependencies are inferred from the claim text.

Image forming apparatus with toner transport mechanism incorporated therein

Life of this patent

Image forming apparatus with toner transport mechanism incorporated therein

Life of this patent

Abstract

Claims44