Closed cell polyurethane foam pen guide damper

Claim 1

A writing stylus assembly for use in a facsimile transceiver wherein the stylus is moved by a carriage to record the incoming facsimile signal on a writing medium such as an electroresistive paper held against a drum, including lever means for moving said assembly manually to a desired position and moving the tip of the writing stylus away from the drum surface upon actuation so that the tip can be moved to the position without touching the drum, a pen guide pivotally mounted on the stylus assembly frame and holding the writing tip of the stylus, a metallic spring positioned between said pen guide and style frame and applying a torque to said pen guide about its pivot so that the stylus tip is urged against the drum so that the tip rides on the surface of the writing medium with a predetermined amount of force, and a flat planar piece of closed cell polyurethane foam responsive to the release of said lever means for counteracting the spring action of said spring means and retarding the return speed of the stylus and thereby preventing said stylus tip from snapping back and hitting the drum, said closed cell polyurethane foam having a hole at the center thereof to hold the spring therein in a position traverse to the flat surfaces, the two major surfaces of said foam being glued onto the stylus assembly frame and pen guide, said pen guide including means for compressing the coil spring by a predetermined amount of pressure to impart an effective amount of torque to said pen guide for urging the stylus tip against the drum, said foam being dimensioned so that at the normal operative position its cells are in a relaxed state.