Browse Prior Art Database

Web Tension Transducer

IP.com Disclosure Number: IPCOM000089594D
Original Publication Date: 1977-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 41K

Publishing Venue

IBM

Related People

Crawford, RP: AUTHOR [+3]

Abstract

A tension transducer for monitoring and controlling the tension in a flexible web, such as a magnetic tape, is described.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 2

Web Tension Transducer

A tension transducer for monitoring and controlling the tension in a flexible web, such as a magnetic tape, is described.

Tape 1 (Fig. 1) is fed between two reels (not shown) via a tape feed path including an idler 2. The idler is pivotally supported on a lever 3 that is connected to a flexural pivot 4, such as the type commercially available from Bendix Corp.

Pivot 4 (Figs. 1 and 2) comprises two coaxially aligned annular cylinders 5, 6 with respective intermeshed semi-cylindrical depending and upstanding extensions 5a, 6a interconnected by flat leaf springs 7a, 7b and 8. Springs 7a, 7b are aligned and disposed in spaced relation at right angles to and at opposite sides of spring 8. Spring 7a is connected to the respective walls of the bores of cylinder 5 and extension 6a; spring 7b is connected to the respective walls of cylinder 6 and extension 5a; and spring 8 is connected to cylinders 5 and 6. Upper cylinder 5 is welded or keyed to a stationary housing 9 so as to be nonrotatable. Lower cylinder 6 is welded or keyed to lever 3, and coaxially connected to a rotary variable differential transformer (RVDT) 10.

Pivot 4 provides accurate, stable positioning of idler 2 and a frictionless restoring torque that is linear with respect to angular deflection. RVDT 10 provides accurate, drift-free position sensing without imposing significant viscous or frictional drags on the system, and its rotational inertia is very low. Tension changes on idler...