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:
Dec. 27, 1988
Filed:
Jul. 20, 1987
Robert H Niemeyer, III, Martinez, CA (US);
AM International Corporation, Chicago, IL (US);
Abstract
A following error limit system is operative within a graphic recording system having a pen carriage moveable along a first path and a media moveable along a second path. A closed loop servo system is operative upon the pen carriage motor and is controlled by a position information processor. A following error processor is coupled to the servo system and compiles a periodically sampled table of absolute position, commanded position and following error for the servo system during the initialization process. The carriage is moved in a first direction at a constant velocity until it impacts a fixed limit stop which impeads further carriage motion. The following error processor determines the absolute or limit position of the pen carriage on the basis of the information derived from the servo system. The system functions without the use of external limit switches and limit detectors.