Engine F/W Contol Algorithm; Feeding; Transfer - Samsung SF-76x series Service Manual

2.2.6. Engine F/W Contol Algorithm

2.2.6.1. Feeding

If feeding from a tray, the drive of the pickup roller is controlled by controlling the clutch. The on/off of the clutch is
controlled by controlling the general output port or the external output port. While paper moves, occurrence of Jam
is judged as below.
Item Description
JAM 0 • After picking up, paper does not reach the Feed Sensor within a predetermined time.
or • After picking up, if the feed sensor is not on, re-pick up will be initiated. After re-picking up, if the
feed sensor is not on after certain time, it is JAM 0
Paper Empty
• Even though the paper reaches to the feed sensor, the feed sensor does not detect the lead edge of
the paper.
JAM 1 • After the leading edge of the paper passes the feed sensor, the trailing edge of the paper does not clear
the sensor the feed sensor after predetermined period of time.

2.2.6.2. Transfer

The charging voltage, developing voltage and the transfer voltage are controlled by PWM (Pulse Width Modulation). The
each output voltage is changeable due to the PWM duty. The transfer voltage admitted when the paper passes the transfer
roller is decided by environment conditions. The resistance value of the transfer roller is changed due to the surrounding
environment or the environment of the set, and the voltage value, which changes due to the environment, is changed through
the AD converter. The voltage value for impressing to the transfer roller is decided by the changed value.
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2. Product spec and feature
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