Abstract: Apparatus for adjusting printhead-to-media spacing in a printer having a frame and a shiftable printhead-carrying carriage mounted on the frame for lateral movement relative to the frame, the apparatus comprising a first immovable mechanical contact actuator anchored to the frame and disposed beyond one end of a print-job range, and a first movable mechanical contact actuator movable with the carriage, positioned toward that side of the carriage which generally faces the first fixed actuator, and engageable with the first fixed actuator during movement of the carriage beyond the one end of the print-job range to cause a positional adjustment of the carriage which effects a change in printhead-to-media spacing.

Abstract: Apparatus for adjusting printhead-to-media spacing in a printer having a frame and a shiftable printhead-carrying carriage mounted on the frame for lateral movement relative to the frame, the apparatus comprising a first immovable mechanical contact actuator anchored to the frame and disposed beyond one end of a print-job range, and a first movable mechanical contact actuator movable with the carriage, positioned toward that side of the carriage which generally faces the first fixed actuator, and engageable with the first fixed actuator during movement of the carriage beyond the one end of the print-job range to cause a positional adjustment of the carriage which effects a change in printhead-to-media spacing.

Abstract: Apparatus for adjusting to different selectable values the printhead-to-media spacing in a printer having a frame and a reversibly, laterally-shiftable printhead-carrying carriage. The carriage is mounted on the frame both for adjusting by rocking to establish different such spacing values, and is also mounted for the usual lateral movement during a printing operation. One or more mechanical actuators that move with the carriage engage one or more associated stationary actuators effectively anchored to the frame in the printer under certain circumstances with movement of the carriage laterally beyond one or both of the opposite ends of its usual print-job range. Movable and stationary actuator interengagements create rotation of a rotatable structure that is carried on the carriage.

Abstract: Apparatus for adjusting to different selectable values the printhead-to-media spacing in a printer having a frame and a reversibly, laterally-shiftable printhead-carrying carriage. The carriage is mounted on the frame both for adjusting by rocking to establish different such spacing values, and is also mounted for the usual lateral movement during a printing operation. One or more mechanical actuators that move with the carriage engage one or more associated stationary actuators effectively anchored to the frame in the printer under certain circumstances with movement of the carriage laterally beyond one or both of the opposite ends of its usual print-job range. Movable and stationary actuator interengagements create rotation of a rotatable structure that is carried on the carriage.

Abstract: A dust shield for preventing paper dust from fouling a printer and printhead mechanism is disclosed. In a sprocket-wheel paper drive printer, the sprockets are at least partially encased as they enter and exit the holes in the paper. Paper particles are trapped and then channelled away from mechanisms, such as a thermal ink jet cartridge printhead, whose operation may be detrimentally affected by such dust.

Abstract: An automatic sheet feed alignment system is described for feeding sheets of print media such as paper to print mechanism in alignment with the print mechanism. A single motor drives a main sheet advance roller, and is also coupled to a sheet pick roller through a non-reversing clutch. An idler roller is disposed adjacent the drive roller. To feed a sheet into the print position, the motor drives the main drive roller and sheet pick roller in a sheet advancing direction, until the sheet leading edge is advanced into and past the nip between the main drive and idler rollers. The motor direction is then reversed so that the main roller retracts the sheet. Because the sheet pick roller is not driven in the reverse direction, a buckle is formed in the sheet between the sheet pick roller and the nip, tending to align the leading sheet edge with the nip. The motor direction is then reversed to drive the sheet forward to the print position, its leading edge having been aligned.

Abstract: A belt tensioner for a belt and pulley system is disclosed. The tensioner has a camming surface upon which a pulley axle rides, maintaining substantially uniform tension in the belt despite competing forces of the belt tension and a tensioner holding spring. The camming surface profile is generated, for example, when using a spring holding mechanism, by differentiating Hooke's Law.

Abstract: A printhead cartridge and carriage assembly (10) for use with ink-jet printers is disclosed. The assembly is provided with means (56) for ensuring that an ink-jet cartridge (20) is securely locked in place in a cartridge carrier (12), means (78, 78a, 80, 80a, 82, 82a) for ensuring that cartridge is registered in a given, fixed, repeatable position each time, means (128) for ensuring that the cartridge is spaced from the printing medium (40) a minimum, fixed distance, means (100) on the carriage for maintaining this fixed distance, and interconnect means (84) for connecting a printhead assembly (34) on the cartridge with a microprocessor for controlling the pattern of ink drop ejection. The assembly further includes a preloader assembly (106) for preventing backward rotational pivoting of the carriage about a slider rod (44) associated with a platen (46) of the printer and for urging the carriage toward the medium on the platen.