Toner Stirring Control via Adhering Amount Sensing
Solution Overview
Problem
Image forming apparatuses face inefficiencies due to unnecessary stirring of toner, as the charge amount of toner does not solely depend on its volume, leading to potential over-stirring even when a sufficient charge is maintained.
Innovation Solution
An image forming apparatus with a control device that determines whether to stir the toner based on the toner adhering amount and development bias voltage, using a test toner image to assess the need for stirring, thereby optimizing toner stirring operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the stirring roller is rotated when the development unit has been stopped for a predetermined time or longer, then the volume of the toner is recovered and the charge amount of the toner is recovered, but unnecessary stirring may be executed when the charge amount is already sufficient
Solution Approach 1:
The control device receives information from the sensing device about the toner adhering amount and adjusts the stirring operation accordingly. When the toner adhering amount indicates sufficient charge, the control device prohibits stirring; when the toner adhering amount indicates insufficient charge, the control device permits stirring. This feedback mechanism eliminates unnecessary stirring while ensuring adequate charge maintenance.
Solution Approach 2:
The system uses its own operational parameters (toner adhering amount and development bias voltage) to automatically determine when stirring is needed, without requiring external monitoring or manual intervention. The sensing device continuously monitors toner conditions and the control device autonomously makes stirring decisions based on predefined criteria.
2Reliability
If the stirring roller is rotated to maintain toner volume, then the charge amount of the toner is improved, but energy is wasted when stirring is not actually needed
Solution Approach 1:
The control device uses real-time feedback from the sensing device about toner adhering amount to control the stirring roller operation. Stirring is activated only when the toner adhering amount falls below a threshold indicating insufficient charge, and deactivated when the threshold is met, thereby eliminating energy waste from unnecessary stirring operations.
Solution Approach 2:
Instead of continuous or time-based periodic stirring, the system implements condition-based periodic stirring where the stirring roller operates only during periods when toner charge becomes insufficient, as detected by the sensing device. This transforms stirring from a routine maintenance operation to a demand-responsive operation.
3Volume of stationary object
If the stirring roller is rotated based solely on stop time condition, then toner volume recovery is ensured, but the actual charge amount status is not considered
Solution Approach 1:
The sensing device provides direct feedback about the toner adhering amount, which is a precise indicator of actual charge status. The control device uses this feedback to override or confirm stop-time-based stirring decisions, ensuring that stirring is based on actual charge needs rather than merely on elapsed time, thereby improving measurement precision of charge amount assessment.
Solution Approach 2:
The system replaces the mechanical/time-based stirring trigger (rotation based on stop duration) with an electrostatic/sensing-based trigger (toner adhering amount detection). This substitution allows direct measurement of charge status through electrical properties rather than inferring charge status from mechanical operation history.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Ensures a sufficient charge amount of toner is maintained without unnecessary stirring, improving operational efficiency by only stirring when necessary.
Implementation Method 1
an electrostatic latent image forming device that forms an electrostatic latent image on the image carrier
Implementation Method 2
a toner carrier that develops the electrostatic latent image into a toner image by imparting the toner to the image carrier
Implementation Method 3
a voltage applying device that applies a development bias voltage between the image carrier and the toner carrier
Data Source
AI summary
An image forming apparatus having an image carrier; an electrostatic latent image forming device that forms an electrostatic latent image on the image carrier; a development device having a housing section that stores toner therein, a stirring device for stirring the toner inside the housing section, and a toner, carrier that develops the electrostatic latent image into a toner image by imparting the toner to the image carrier; a voltage applying device that applies a development bias voltage between the image carrier and the toner carrier; a control device that makes the electrostatic latent image forming device and the development device form a test toner image on the image carrier; and a sensing device that senses a toner adhering amount of the test toner image. The control device determines whether to make the stirring device stir the toner based upon a relation between the toner adhering amount of the test toner image and the development bias voltage that was applied by the voltage applying device for formation of the test toner image.