Toshiba e-STUDIO281c Service Manual page 8

6.4 Description of Operation ...................................................................................................... 6-5
6.4.1 Scan motor (M1)....................................................................................................... 6-5
6.4.2 Scanning drive circuit ............................................................................................... 6-6
6.4.3 Initialization at power-ON ......................................................................................... 6-7
6.5 Control of Exposure Lamp (EXP) ........................................................................................ 6-8
6.5.1 General description .................................................................................................. 6-8
6.5.2 Exposure lamp (EXP) ............................................................................................... 6-9
6.5.3 Control circuit for the exposure lamp...................................................................... 6-10
6.6 General Description of CCD Control.................................................................................. 6-11
6.6.1 Opto-electronic conversion..................................................................................... 6-11
6.6.2 Shading correction ................................................................................................. 6-11
6.7 Automatic Original Size Detection Circuit .......................................................................... 6-12
6.7.1 Principle of original size detection .......................................................................... 6-12
6.7.2 Process of detection of original size ....................................................................... 6-13
6.8 Disassembly and Replacement ......................................................................................... 6-17
7. IMAGE PROCESSING .................................................................................................. 7-1
7.1 General Description ............................................................................................................. 7-1
7.2 Construction......................................................................................................................... 7-3
7.3 SYSTEM CONTROL PC BOARD (SYS) ............................................................................. 7-4
7.3.1 Features ................................................................................................................... 7-4
7.3.2 Functions of image processing circuit ...................................................................... 7-4
7.4 LOGIC PC BOARD (LGC) ................................................................................................... 7-9
7.4.1 Features ................................................................................................................... 7-9
7.4.2 Functions of image processing circuit ...................................................................... 7-9
8. LASER OPTICAL UNIT ................................................................................................ 8-1
8.1 General Description ............................................................................................................. 8-1
8.2 Structure .............................................................................................................................. 8-3
8.3 Laser Diode ......................................................................................................................... 8-7
8.4 Laser Unit Cooling Fan ........................................................................................................ 8-8
8.5 Polygonal Motor (M4) .......................................................................................................... 8-9
8.6 Laser Driving PC Board (LDR) .......................................................................................... 8-10
8.7 Disassembly and Replacement ......................................................................................... 8-11
9. DRIVE SYSTEM ............................................................................................................ 9-1
9.1 General Description ............................................................................................................. 9-1
9.2 Main Motor (M6) .................................................................................................................. 9-2
9.2.1 Construction ............................................................................................................. 9-2
9.2.2 Drive circuit of main motor........................................................................................ 9-3
9.3 Transport Motor (M9)........................................................................................................... 9-4
9.3.1 Construction ............................................................................................................. 9-4
9.3.2 Drive circuit of transport motor ................................................................................. 9-5
9.4 Developer Motor (M11)........................................................................................................ 9-6
9.4.1 Construction ............................................................................................................. 9-6
9.4.2 Drive circuit of developer motor................................................................................ 9-8
9.5 Disassembly and Replacement ........................................................................................... 9-9
10. PAPER FEEDING SYSTEM........................................................................................ 10-1
10.1 General Descriptions ......................................................................................................... 10-1
10.2 Construction....................................................................................................................... 10-2
10.3 Functions ........................................................................................................................... 10-3
10.4 Description of Operation .................................................................................................... 10-4
10.4.1 Drive of rollers ........................................................................................................ 10-4
10.4.2 Operation of bypass pickup roller ........................................................................... 10-4
10.4.3 Operation of drawer pickup roller ........................................................................... 10-5
10.4.4 Separation of paper ................................................................................................ 10-5
e-STUDIO281c/351c/451c CONTENTS
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June 2005 © TOSHIBA TEC