Abstract: A low-profile keyboard (5) each switch (3) having a dished keybutton (3) held upward by a rubber dome (49) and having ribs (55) which depress extension (43 and 31) which carry electrical traces (45 and 33) to activate the switch. The assembly is mounted on post (15). A lower recess (21) permits excess travel to a quiet stop. The rubber sheet (47) provides spill resistance.

Abstract: A portable personal computer has a display screen movable between a substantially vertical position when a keyboard is in a substantially horizontal position and exposed for use and a substantially horizontal position in which the keyboard is not accessible or viewable but the display screen is accessible and viewable. In its substantially horizontal position, the display screen can be used as a book reading device or a pen based personal computer, for example. When the display screen is in its substantially horizontal position, function control buttons are accessible.

Abstract: A thermal printer (10) has a thermal transfer medium (28) fed past a thermal printhead (21) at a substantially constant velocity by a feed roll (82) engaging the thermal transfer medium just prior to the printhead to maintain a portion of the thermal transfer medium between the printhead and the feed roll relatively stiff. The feed roll is mounted on a cartridge (30) having the thermal transfer medium supplied therefrom. A drag brake (70) is disposed in the feed path of the thermal transfer medium prior to the feed roll to cause a substantially constant premetering tension to be applied to the thermal transfer medium irrespective of the coefficient of friction between the drag brake and the thermal transfer medium. A carrier (14), which supports the printhead and a feed roll driver (90), is driven separately from the feed roll driver so that various ratios between the velocities of the thermal transfer medium and the carrier are obtained to produce various print qualities.

Abstract: A paper feed roll assembly is disclosed which is pivotally mounted on a central point with three degrees of freedom of movement. The feed rolls are engageable with the periphery of the platen. Additionally, the support for the paper feed rolls is deflectable about the central point by a feed roll release member to effect the withdrawal of the feed rolls from the periphery of the platen to enhance paper insertion and removal. The pivot point support provides for freedom of movement in the three necessary degrees of freedom to allow equilization of feed roll force against the platen and for alignment of the feed rolls with the periphery of the platen to insure proper paper feed. The feed roll truck frame, by virtue of its pivotal mounting, may be deflected downward to permit release or insertion of the paper. A deflection means or eccentric bar is disclosed for deflecting the truck member away from the periphery of the platen against the force of the pivot support acting toward the platen.