JP2006071722A5 - - Google Patents

Claims (8)

Electrodes for electrostatically transporting the fine particles are arranged, and an electric substrate for electrostatically transporting the fine particles to the development site of the image carrier on which a latent image is formed. In the developing device for developing the latent image formed in
A developing device characterized in that the electrostatic transport direction of the fine particles by the electric substrate can be switched between one direction and the opposite direction . The developing device according to claim 1, wherein the fine particle conveyance path by the electric substrate has a folded portion for folding and making a U-turn.   Phase excitation output means for generating a phase timing signal for each phase in a preset order in a time period based on an input clock; and a phase timing signal for each phase output by the phase excitation output means The developing device according to claim 1, wherein the output order is switched to change the electrostatic conveyance direction of the fine particles.   A reverse switching instruction cycle output means for outputting a preset second time period, and the reverse switching instruction cycle output for changing the output order of the phase timing signal for each phase output by the phase excitation output means; 4. The developing device according to claim 3, wherein the developing device is repeatedly executed for each second time period output by the unit to switch the electrostatic transport direction of the fine particles for each second time period. It has a transport state detection means to detect the conveyance amount during the electrostatic transportation of the fine particles,
From the transport amount detected by the transport state detection means, the degree of transport of fine particles is determined, the output order of the phase timing signal for each phase output from the phase excitation output means is changed, and the electrostatic transport of fine particles The developing device according to claim 3, wherein the direction is switched. It has a concentration detection means to detect the deposition concentration of fine particles in the developed image on the image bearing member,
The degree of particle conveyance clogging is determined from the concentration detected by the concentration detection unit, the output order of the phase timing signal for each phase output by the phase excitation output unit is changed, and the electrostatic conveyance direction of the particle is determined. The developing device according to claim 3, wherein the developing device is switched. Voltage generating means for determining electrostatic transport strength by the electric substrate ;
Frequency generating means for determining an electrostatic conveyance speed by the electric substrate ;
To increase or decrease the output voltage value of said voltage generating means, and control means for executing either one or both to increase or decrease the output frequency value of the frequency generating means,
Have
The control by the control means is executed when the output order of the phase timing signals for each phase outputted by the phase excitation output means is changed and the electrostatic conveyance direction of the fine particles is changed. Development device. An image carrier on which an electrostatic latent image is formed;
The developing device according to claim 1, wherein the electrostatic latent image is developed with a developer.
An image forming apparatus comprising: