Browse Prior Art Database

Read Only Memory Utilizing Mechanical Time Domain Reflectometry

IP.com Disclosure Number: IPCOM000095135D
Original Publication Date: 1965-Sep-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Hill, YM: AUTHOR [+2]

Abstract

The mechanical record medium reading apparatus senses the presence of holes in a record medium (RM) 83. This is effected by detecting the stress waves reflected from the data bit holes (H) 102 in the path of a mechanical shear wave. The latter moves in the zero shear mode in a normally homogeneous medium.

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 83% of the total text.

Page 1 of 2

Read Only Memory Utilizing Mechanical Time Domain Reflectometry

The mechanical record medium reading apparatus senses the presence of holes in a record medium (RM) 83. This is effected by detecting the stress waves reflected from the data bit holes (H) 102 in the path of a mechanical shear wave. The latter moves in the zero shear mode in a normally homogeneous medium.

A launching and sensing unit LS 84 comprises a plurality of standard piezoceramic shear transducers T 85... T 88. T's 85 and 87 are placed on opposite sides of RM 83 and are caused to move in a direction indicated by a pair of arrows 92. Such movement in response to input drive voltage as applied thereto in a standard manner. T's 86 and 88 are placed on opposite sides of the RM 83 and slightly spaced from T's 85 and 87 respectively, a distance 94. T's 86 and 88 are caused to move in a direction of the arrows 96 in response to a similarly applied drive voltage.

The back support for the T's is not shown and can be of any standard are type. The simultaneous movement of the corresponding pairs of transducers generates a zero mode shear stress in the area 97 between the corresponding pairs of transducers. The shear stress propagates through RM 83 and is absorbed by pairs of absorption pads 98 and 100. Such pads are placed at opposite ends and in contact with the RM 83.

The area of the record medium between the pads 98 and 100 is scanned by the zero shear wave in the following manner. H 102 reflects a sma...