CHAPTER 3 THEORY OF OPERATION

2.2Paper Transfer

2.2.1Paper supply

The paper pick-up roller picks up one sheet of paper from the paper cassette every time it is rotated and feeds it to the paper feed roller.

Pinch roller

 

Paper feed roller

Paper pick-up roller

Front registration

Pinch roller

sensor lever

 

Pressure plate

Separation pad

 

 

Fig. 3-29

The paper is gripped between the paper pick-up roller and the separation pad and separated into individual sheets.

The pick-up roller is directly connected to the clutch mechanism, whose rotation is stopped by the stopper arm. When the pick-up solenoid is activated, the clutch mechanism is engaged by the solenoid action and the paper pick-up roller is driven. The paper drawn out of the tray by the pick-up roller pushes against the front registration sensor lever and the paper top position/absence of paper is detected by sensing the motion of the lever.

2.2.2Paper registration

After the paper top position is detected by the front registration sensor, the paper, separated into individual sheets by the paper pick-up roller, is fed further for a specified time, and the paper top position reaches the paper feed roller so that the paper skew is adjusted. Then, the solenoid is turned off, the paper feed roller starts turning, and the paper is fed to the transfer block in the drum unit.

Photosensitive drum

Paper feed roller

Transfer roller

Rear registration sensor lever

Fig. 3-30

The rear registration sensor in the path from the feed roller to the transfer roller controls the first print position on the paper.

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Brother 1250, HL-1030, 1240 service manual Paper Transfer, Paper supply, Paper registration