Image forming apparatus including a toner recycling mechanism
AssigneeRicoh Company, Ltd.
InventorsSatoshi Muramatsu, Nobuo Kasahara, Takashi Hodoshima
Life of this patent
Estimating the term…
Abstract
In an electrophotographic image forming apparatus including a toner recycling mechanism, a collected toner conveying device is free from troubles particular to a conventional device using a screw pump and an air pump and conveying toner and air mixture via an elastic tubing, i.e., the wear of a stator due to aging and a decrease in the delivery pressure of the pump ascribable to the wear. A control device controls, based on the cumulative operation time, an operation of the screw pump and an operation of the air pump. This provides the toner conveying device with durability, reliability and simple construction while insuring toner conveyance and reducing cost.
Claims12
An image forming apparatus including an image carrier and capable of recycling toner, comprising:
- a screw pump including a female screw type stator formed with a spiral groove in an inner periphery thereof and a male screw type rotor rotatably received in said stator;
- air feeding means for scattering and thereby fluidizing collected toner to be delivered from said screw pump via a tubing;
- first drive means for selectively starting or stopping driving said screw pump independently of the image carrier;
- a timer for counting a cumulative operation time of the image carrier;
- and
- control means for controlling, based on the cumulative operation time, an operation of said screw pump and an operation of said air feeding means.
Dependencies are inferred from the claim text.