Canon BJC 50 Service Manual - Page 118

Part 4: Technical Reference BJC-50 3.4 Paper Feed Mechanism 3.4.1 Outline of paper feed mechanism In this printer paper is fed manually, one sheet at a time. The paper feed mechanism of the printer is divided into the paper pick-up section and printing/paper-delivery section. These operations are driven by the paper feed motor which feeds the paper at a line feed pitch of 1/360 inch. a) Paper pick-up section The paper pick-up section consists of the paper feed roller and the pinch rollers. Paper is fed through the paper feed slot, one sheet at a time. When the paper is detected by the paper end sensor and reaches the contact point of the paper feed roller and the pinch rollers, the printer acknowledges the presence of paper. To bring the paper to the print start position, press the RESUME button. The paper feed roller driven by the paper feed motor will feed in the paper to its set position. b) Printing/Paper delivery section The printing section consists of the paper feed roller, the pinch rollers on the platen and the carriage. Each part is responsible for ensuring that a certain head-to-paper distance is maintained. The paper delivery operation section consists of the eject roller and spurs that deliver the printed paper. Paper set to the print start position by the paper feed roller and the pinch rollers will be printed over the platen and delivered by the eject roller and the spurs. This printer has a sensor that detects if paper has been delivered correctly. Do not attempt to back feed paper through the paper delivery slot as this may damage the sensors. Spurs Paper Feed Roller Printer Delivery Sensor Paper Feeding Direction Eject Rollers Pinch Roller Paper Sensor Figure 4-23 Paper Pass 4-30