Canon LBP 2460 Service Manual - Page 45

CHAPTER 2 OPERATION AND TIMING 1. This chapter describes the printer functions, the relationships between mechanisms and circuits, and the timing of operations. Mechanical linkages are indicated by black and white lines ( ), the flow of control signals by solid arrows ( ), and the flow of groups of signals by outline arrows ( ). 2. An active-high signal is indicated by "H" or by a signal name without a slash in front of it, such as "PSNS." An active-low signal is indicated by "L" or by a signal name with a slash in front of, such as "/SCNON." A signal that is "H" or has a name without a slash is active at the supply voltage level (indicating that the signal is being output), and inactive at ground level (indicating that the signal is not being output). A signal that is "L" or has a slash in front of its name is active at ground level, and inactive at the supply voltage level. There is a microcomputer in this printer. But as the internal operation of the microcomputer cannot be checked, an explanation of the operation of the microcomputer has been left out. As it is assumed that no repair will be made to customer circuit boards, the explanation of board circuits is limited to an outline using block diagrams. So there are two types of circuit explanations; (1) everything from the sensor to the input sections of the major circuit boards, (2) everything from the output sections of the major circuit boards to the loads. These are explained with block diagrams according to the function. I. BASIC OPERATION 2-1 II. ENGINE CONTROL SYSTEM ....... 2-4 III. LASER/SCANNER SYSTEM 2-26 IV. IMAGE FORMATION SYSTEM ..... 2-32 V. PICK-UP/FEED SYSTEM 2-42 VI. OVERALL CONTROL SYSTEM ..... 2-60 VII. OPTION CONTROL SYSTEM ....... 2-64 VIII. ENVELOPE FEEDER 2-67 IX. DUPLEXING UNIT 2-71 X. PAPER DECK 2-81