Service Manual 2-13Printhead TiltThe printhead is able to rotate into four basic positions:1. Printhead lock / ship position (19.5 degrees) The printhead restraint pins areresting against the right and left locks. In this position, the printhead tilt arm/follower is free of the tilt cam, and the head is secured for shipping.2. Wipe position (12 degrees) The printhead tilt arm/follower is engaged with thetilt cam, and the head overload spring contact is engaged with the overloadspring-plate to provide the correct force for the wiper.3. Standby position (20.9 degrees) Allows the wiper to clear the printhead in orderto be in the start wipe printhead position, and also allow the printhead locks topivot and lock or unlock the printhead. In this position, the printhead tilt arm/follower is engaged at the standby position of the tilt cam.4. Print position (0 degrees) The printhead is forward and resting against the rightand left head-to-drum buttons. The head-to-drum buttons define the spacebetween the jet stack and the drum.The tilt cam tilts the head into the basic four positions listed above. The cam has fivespecial features and associated functions:1. The cam is combined with a missing tooth gear that allows the cam to be inactivein the print position, which frees the process drive to perform other printeroperations.2. The cam has a latching feature to unlatch and latch the missing tooth gear toengage the printhead tilt drive train.3. The cam profile has a standby dwell (the portion of the cam that has a constantradius), that holds the printhead back in the standby position4. The cam profile has a wipe dwell the holds the printhead back in the wipeposition.5. The cam profile increases the power consumption at a specific phase of rotation.This allows the software to identify a power consumption footprint that alerts thesystem to a fault when the head is locked in error.The printhead is tilted away from the drum and locked for shipping. The printhead islocked if the green head lock indicator is above the level of the tray. When theprinthead is locked in the shipping position there are three key restraining elements:1. The printhead is restrained from rotating from the shipping position by pinsextending from both ends of the printhead into a pocket. These pockets aredefined by dampening pads that limit motion to the back and polycarbonate locksthat pivot into the lock position and limit forward motion toward the drum. Thelocks are held in the lock position by the wiper carriage, and are spring-loaded tonormally be unlocked.2. The printhead is restrained at the X-Axis shafts by the right and left headrestraints that limit motion at both ends of the printhead.3. The printhead is limited to the nominal motion of 1.7mm in the X-Axis (left /right side motion when the printhead is back and locked) by the right lock and theleft home stop on the left side frame.
