Hewlett-packard Company

Allan G Olsen

Tod S Heiles

James O Beehler

Chong S Yoon

A printer is disclosed having an improved paper feed mechanism. The improved paper feed system has a reduced cost and accepts a wide variety of paper types including continous forms and single cut sheets fed both by hand and from a paper tray. Furthermore, the printer is capable of switching from one paper source to another without requiring the operator to unload and reload paper. The mechanism operates with only two motors and no solenoids. Control over the paper path is maintained by employing the carriage to select the paper path and lift the ball. The printer also has a novel paper sensor.

Unified paper path printer with automatic parking feature

The invented printer includes a carriage-actuated clutch and a motor-driven gear element. The clutch is selectively engageable with the element and causes the printer to perform different tasks when engaged. More specifically, the invented printer includes a motor-driven gear, a printhead and a printhead carriage, a clutch having a flexible portion, and a gripping surface on the flexible portion for engaging the motor-driven gear. To actuate the clutch, the carriage pushes against the clutch causing it to flex and engage the motor-driven gear. When engaged, rotating the gear a predetermined distance causes the clutch to rotate a predetermined distance, in turn causing the printer to perform a certain task. Continuing to rotate the clutch causes the printer to perform other tasks. The invented printer also includes a paper-feed mechanism for picking up and feeding a sheet of paper into the printer. This mechanism incudes a rotatable drive roller that moves paper through the printer, a spring-biased plate capable of pivoting around an axial pivot, biased to extend toward the drive roller and on which paper is tacked, a partition, having at least one opening, positioned between the roller and the plate for generally preventing the roller from contacting the media on the plate, and a pivot adjacent the roller for selectively allowing at least a part of the roller to extend through the opening in the partition to contact the top sheet of paper and feed it through the printer. The paper-feed mechanism is one task that may be triggered by the carriage-actuated clutch.

Growing community of inventors

Camas, WA, United States of America

Allan G Olsen