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Outline of the TD sensor
In this model, a non-contact toner density (TD) sensor, which we also call a mu ) sensor, is used for toner density control.
The TD sensor is attached on the lower side of the development unit. Unlike a HST sensor, the board of the TD sensor is exposed. So there is a cover around the sensor to protect it and to maintain a good contact between the sensor and development unit.
The TD sensor measures the permeability of the developer without contacting it, from the outside of the case, and converts the measured value to the toner density.
According to the toner density measured by this sensor, the proper amount of toner is supplied to the developer.
A counter corresponding to the frequency is used as the unit of TD sensor output. Thus, unlike a HST sensor which directly detects Vt, the TD sensor output is converted into Vt for toner supply control.
In the TD sensor, there is an ID chip storing the machine identification information, the running distance information of development unit and PCU, and other information used by image density control.
7.6.2 PROCESS CONTROL
Outline
Process control adjusts the condition of the imaging hardware to maintain a constant image density. Process control is executed at the following times.
Process Control | Operative Condition | Related SPs | |
1 | PowerON ProCon :Set | When a certain time has passed after the previous job end (Except when recovering from an SC or jam) | SP3-530-001 SP3-530-002 SP3-530-003 SP3-530-004 SP3-530-005 SP3-530-006 SP3-530-007 SP3-530-008 |
2 | JobEnd ProCon :Set | When the value of the job end counter becomes more than the threshold (At job end) | SP3-534-001 to 004 SP3-534-011 to 014 |
Detailed Descriptions
Detailed Descriptions
Detailed Descriptions