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File Protection for Data Storage Carriers Disclosure Number: IPCOM000094668D
Original Publication Date: 1965-Apr-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 39K

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Related People

Nagakura, H: AUTHOR [+1]


This device provides security protection for selected data stored in a data cell.

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File Protection for Data Storage Carriers

This device provides security protection for selected data stored in a data cell.

Each data cell normally contains two-hundred separate data strips arranged in twenty subcells, i.e., ten strips to a subcell. To insure proper alignment of the desired subcell with the strip picking mechanism, a safety device is provided. Arcuate ledge 1 is located on the outer top edge of the data cell. Ledge 1 has twenty spaced slots 2. Each slot 2 is aligned with a subcell. Phototransistor 3 and light 4 are mounted above and below ledge 1. The phototransistor 3 output prevents the strip picking mechanism from operating if the light path

Manually removable masks or plugs 5 are inserted in the slits corresponding to subcells containing confidential or security type information. Since the light path is thus blocked, access to this information is prevented.

This technique can be extended to protect data which is frequently read, but seldom if ever changed, by providing a second slotted ledge 6, a phototransistor 7 and a light 8. Phototransistor 7 is connected to the write circuits which are disabled whenever the light path to 7 is blocked. Thus, a pluggable mask in one of the slots of ledge 6 allows a desired strip to be picked and read, but prevents the information on the strip from being rewritten.


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