List of figures Figure 1-1. HP color LaserJet 2550 series printer identification label .................................8 Figure 2-1. Space required ................................................................................................32 Figure 2-2. Standard and optional input trays—HP color LaserJet 2550 series printers ............................................................................................................37 Figure 2-3. Printer output paths .........................................................................................38 Figure 3-1.
Smearing..........................................................................................................61 Figure 3-2. Toner specks ...................................................................................................61 Figure 3-3. Loading the cleaning page in tray 1 ................................................................62 Figure 4-1. Cross-section of the printer .............................................................................68 Figure 4-2. Engine control system (includes the basic configuration of the printer) .........70 Figure 4-3.
Power-on sequence ........................................................................................72 Figure 4-4. Motors and fans...............................................................................................73 Figure 4-5. Laser/scanner system .....................................................................................74 Figure 4-6. Pickup and feed system ..................................................................................76 Figure 4-7. Optional tray 2 (250-sheet paper tray) ............................................................77 Figure 4-8.
Photosensors and switches (1 of 2) ................................................................78 Figure 4-9. Photosensors and switches (2 of 2).................................................................79 Figure 4-10. Solenoid ..........................................................................................................80 Figure 4-11. Clutches ..........................................................................................................81 Figure 4-12. Printed circuit assemblies (1 of 2) ...................................................................82 Figure 4-13.
Printed circuit assemblies (2 of 2) ...................................................................83 Figure 4-14. Image-formation system ..................................................................................84 Figure 4-15. Image-formation process ................................................................................85 Figure 4-16. Step 1: primary charging .................................................................................86 Figure 4-17. Step 2: laser-beam exposure ..........................................................................86 Figure 4-18.
Developing block .............................................................................................87 Figure 4-19. Step 3: developing ..........................................................................................87 Figure 4-20. Step 4: primary transfer ...................................................................................88 Figure 4-21. Step 5: secondary transfer ..............................................................................89 Figure 4-22. Step 6: separation ...........................................................................................89 Figure 4-23. Step 7:
fusing ..................................................................................................90 Figure 4-24. Step 8: roller charging (auxiliary transfer belt cleaning roller) ........................90 Figure 4-25. Step 9: roller charging (transfer belt cleaning roller) .......................................91 Figure 4-26. Step 10: transfer belt cleaning ........................................................................92 Figure 4-27. Step 11: drum cleaning ...................................................................................93 Figure 4-28.
Print cartridge ..................................................................................................94 Figure 4-29. Print-cartridge E-label .....................................................................................95 Figure 5-1. Removing the fuser cover (and fuser) ..........................................................105 Figure 5-2. Removing the right-side cover (1 of 2) ..........................................................106 Figure 5-3. Removing the right-side cover (2 of 2) ..........................................................107 Figure 5-4.
Removing the control panel (1 of 2) ..............................................................108 Figure 5-5. Removing the control panel (2 of 2) ..............................................................109 Figure 5-6. Removing the on-off switch ...........................................................................110 Figure 5-7. Removing the interface cover .......................................................................111 Figure 5-8. Removing the formatter cage (1 of 2) ...........................................................112 Figure 5-9. Removing the formatter cage (2 of 2) ...........................................................113 ENWW xi