Image Stabilization Control Study the image stabilization control mechanism.

Image Stabilization Control

　

○Purpose: Here, you will learn about the control mechanism executed by the image formation system to ensure stable reproduction of images of a specific level of quality.

　

　

1. Outline

As changes occur in the site environment or wear starts to show as the machine is used over time, the density of output could well be affected if left unattended. To prevent a drop in image quality, the DC controller corrects the various high-voltage outputs so that the image density will remain at a specific level. The following are the control mechanisms used for image stabilization:

　

　APVC control: corrects the bias applied to the primary charging roller to suit the thickness of the coating of the photosensitive drum.

　ATVC control: corrects the bias applied to the transfer charging roller to suit the site environment.

2. APVC Control

a. Outline

The term APVC stands for “auto primary voltage control,” and it is used to refer to the remedial mechanism executed to correct the DC voltage applied to the primary charging roller in keeping with the degree of wear on the photosensitive drum.

b. Timing of Execution

∙ when the drum unit has been replaced (executed by the service person using service mode)

∙ when as manual as 500 prints have been made (cumulative)

c. Particulars of Control

The DC controller applies a bias to the primary charging roller to check the thickness of the coating of the photosensitive drum with reference to the level of current that flows through the photosensitive drum. Then, the DC controller corrects the DC bias applied to the primary charging roller to suit the result of the check (measurement of the coating).

　

　

3. ATVC Control

a. Outline

The term ATVC stands for “auto transfer voltage control,” and is used to refer to the remedial mechanism executed to correct the current that flows through the transfer roller to suit the site environment.

b. Timing of Execution

∙ at power-on

∙ at start of printing

c. Particulars of Control

The DC controller applies a bias to the transfer charging roller, and checks the level of current that flows through the roller. Then, the DC controller corrects the transfer charging DC bias so that the current that flows through the transfer charging roller will remain at a specific level.