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:
Aug. 28, 1990
Filed:
Oct. 28, 1988
Richard W Van Pelt, Boulder, CO (US);
Patrick K Wong, Louisville, CO (US);
Joseph W Kern, Lafayette, CO (US);
Storage Technology Corporation, Louisville, CO (US);
Abstract
A tape threading arm mechanical linkage undergoes significant variations in mechanical advantage through its motion. In order to compensate for the drastic changes in the mechanical advantage of the tape threading arm, the operation of the tape threading arm is divided up into a plurality of control segments. Each segment represents a portion of the tape threading path wherein the mechanical advantage of the tape threading arm remains fairly constant. A control memory stores data indicative of various control parameters that are required to regulate the operation of the tape threading arm motor to maintain the tape speed throughout this segment of the tape threading path at a constant velocity. In addition, the measured velocity of the magnetic tape as it is removed from the file reel is used to compute the difference between the predicted operation of the tape threading arm and the measured operation of the tape threading arm. The difference between the expected and measured operations is used to generate feedback signals to vary the current in the tape threading arm motor and the file reel motor to maintain a constant tape velocity, tape tension and minimum torque load on the tape threading arm.