Patent ID: 7874507
Filing Date: 2011-01-25
Classification: G11B

Abstract:
1. In a tape drive, a tape tension modulation system for adjusting the tension of a tape medium in said tape drive comprising: a tape guide; said tape guide being fixed at a position in a tape path; a tape bearing portion on said tape guide adapted to engage a tape medium in said tape path; one or more drag elements operatively associated with said tape guide to exert a drag force that affects downstream tape tension; said one or more drag elements comprising any one of 1) not more than a single set of air ports on said tape guide in communication with a common air pressure source to change a friction coefficient of said tape bearing portion by selectively applying either positive or negative air pressure (but not both simultaneously) to said tape medium, 2) skiving edges on said tape guide in communication with an air pressure source to change a friction coefficient of said tape bearing portion by extending or retracting said edge members, 3) skiving edges on said tape guide controlled by transducers to change a friction coefficient of said tape bearing portion by moving into and out of engagement with said tape medium, 4) a brake adapted to slow rotation of said tape guide to increase downstream tension in said tape medium, and 5) a motor adapted to speed up rotation of said tape guide to decrease downstream tension in said tape medium; a tape tension control circuit for controlling operation of said one or more drag elements in order to alter tape tension during tape drive operations in response to changes in tape tension detected during said tape drive operations.