Developing device, process cartridge, and image forming apparatus

The developing device improves toner concentration detection accuracy and stability by using separate transport screw paths and positioning the sensor optimally, addressing startup inconsistencies and ensuring stable image density.

JP2025137033APending Publication Date: 2025-09-19RICOH CO LTD
2 Cites 0 Cited by

Patent Information

Application Number
JP2024036002
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-03-08
Publication Date
2025-09-19

AI Technical Summary

Technical Problem

Conventional developing devices suffer from low detection accuracy and instability in toner concentration sensor readings, especially at startup, leading to inconsistent toner concentration and image density.

Method used

The developing device incorporates a first and second transport screw configuration forming separate circulation paths, with a toner concentration sensor installed below a partition at the bottom of the second transport path near a communicating section, optimizing its detection area for stable and accurate toner concentration measurement.

Benefits of technology

Enhances the accuracy and stability of toner concentration detection, ensuring consistent developer concentration and image density even during device startup.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

To stabilize a detection result from a toner concentration sensor even when the toner concentration sensor has high detection accuracy and even immediately after the start of the drive of a developing device.SOLUTION: A developing device is provided with a partition part 13e that partitions a first conveyance path B1 in which a first conveying screw 13b1 is installed, and a second conveyance path B2 in which a second conveying screw 13b2 is installed from each other, in an area excluding a first communication part 13f formed on one end side in a longitudinal direction and a second communication part 13g formed on the other end side in the longitudinal direction. The developing device is further provided with a toner concentration sensor 13x that detects the concentration of toner in developer G. The toner concentration sensor 13x has a detection area N in its longitudinal direction installed at a position below the partition part 13e on the bottom of the second conveyance path B2, the position being closer to the first communication part 13f.SELECTED DRAWING: Figure 5
Need to check novelty before this filing date? Find Prior Art