Browse Prior Art Database

Sampling Device for Magnetically Recorded Information

IP.com Disclosure Number: IPCOM000091744D
Original Publication Date: 1968-May-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 32K

Publishing Venue

IBM

Related People

Davis, CJ: AUTHOR [+2]

Abstract

The device provides sampled low-speed reading of a magnetic tape moving at high speed. In the upper drawing, read member 1 has read heads 2 and 3, located 180 degrees apart and associated rollers 4 and 5 that drive tape 6 at two different speeds, normal speed N and high speed X. In one mode, member 1 remains stationary for normal tape reading. In another mode, member 1 rotates to sample tape 6 during a high-speed search.

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 100% of the total text.

Page 1 of 2

Sampling Device for Magnetically Recorded Information

The device provides sampled low-speed reading of a magnetic tape moving at high speed. In the upper drawing, read member 1 has read heads 2 and 3, located 180 degrees apart and associated rollers 4 and 5 that drive tape 6 at two different speeds, normal speed N and high speed X. In one mode, member 1 remains stationary for normal tape reading. In another mode, member 1 rotates to sample tape 6 during a high-speed search.

Points A and B are 180 degrees apart on the circular pathway of heads 2 and
3. In the normal low-speed mode, one head 2 or 3 is positioned at point B to read tape 6 as it is driven at speed N. In the high-speed mode, heads 2 and 3 are rotated by member 1 at a linear speed Y. Tape 6 is moved by rollers 4 and 5 in the same direction as heads 2 and 3, but at speed X. The relative speeds are selected so that X-Y equals the normal reading speed N.

The start of a sample operation is shown in the middle drawing. Portion CD of tape 6 has just reached head 2. Due to the difference in speeds between the tape and heads by the time head 2 reaches point B, point D on tape 6 has also reached point B. As a result, only portion CD has been read, but tape 6 has moved a distance corresponding to section CE. Head 3 is now in a position to read portion EF in the lower drawing.

1

Page 2 of 2

2

[This page contains 1 picture or other non-text object]