The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 04, 1989
Filed:
Jul. 24, 1987
Samuel A Stodder, Encinitas, CA (US);
Robert D Haselby, Escondido, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A rigid link is provided between a plot medium (14) and a position transducer (50) so that accurate plot medium advance measurement can be attained. The device (30) comprises a movable carriage (42) and an arm-like extension (38) that juts out from the carriage to the plot medium. A friction hold is made between the extension arm and the plot medium by applying a force to the extension arm normal to the plot medium by means of an electromagnet (33) which includes a coil (34), the extension arm serving as the armature. The electromagnet is located beneath the platen (12) which supports the medium on a base (32) which also supports the carriage. With the electromagnet activated, the extension arm is held against the plot medium. As the plot medium is advanced by a plot medium drive system (20), the extension arm and carriage are pulled along. Plot medium advance is stopped when the proper advance distance has been sensed by the position transducer. The electromagnet is then deactivated and the extension arm and carriage are retracted by a return spring (48) to their original position. The process can then be repeated for the next plot medium advance. The length of a single move is short but sufficient for a scanning type plotter or printer.