Browse Prior Art Database

Variable Thickness Card Reader Magnetic Media

IP.com Disclosure Number: IPCOM000080545D
Original Publication Date: 1974-Jan-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Bradley, TW: AUTHOR [+2]

Abstract

This is a magnetic card reader having parallel displaced capstan diameters axes located at distances slightly less than one card length apart.

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Variable Thickness Card Reader Magnetic Media

This is a magnetic card reader having parallel displaced capstan diameters axes located at distances slightly less than one card length apart.

Pivotable upper member 16 contains two crowned pressure rollers 10, 12, three position sense switches 22, 24, 26, and a magnetic read head 14. Head and pressure roller loading is achieved through use of a common suspension arm centrally loaded with compression spring 28 and retained by quarter-turn service latch 30.

As a card, not shown, enters the transport, first sense switch 22 is activated and a motor, not shown, is energized in the forward (entry) direction. The first pressure roller 10/capstan 2 pinch point action pulls the card into the transport. An initial clearance adjustment between read head 14 and capstan 4 (when both pressure rollers 10, 12 are in contact with their own capstans 2, 6) is required to prevent undue system drag and subsequent head wear. Since the pressure rollers 10, 12 and the head 14 are mounted on a common arm 16, all three are displaced an amount equal to the card thickness. Therefore, the distance between the read head 14 and capstan 4 will always be slightly greater than the distance between any pressure roller/capstan combination, and the card will only be driven by this first drive station.

As the card is driven out of the first drive station 2, 10, head 14 is lowered onto the card an amount equal to the initial head-gap clearance. Since head...