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US5675321A Expired / Lapsed US ⏱️ 0.0 years remaining

Personal computer security system

Assignee: Individual
•
Filing: 1995-11-29
•
Granted: 1997-10-07
•
Expires: 2015-11-29
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Abstract

Abstract The personal computer security apparatus of the present invention provides a security architecture embedded within the personal computer itself to provide a practical level of security to thereby discourage theft of the personal computer. Apparatus are provided to monitor the continuity of the connection to the telephone line to which the personal computer is connected. Loss of voltage continuity on the telephone line for greater than a predetermined period of time is indicative of an individual unplugging the personal computer from the phone jack in order to enable the person to move the personal computer. Motion sensor switches are optionally provided to detect physical movement of the personal computer in excess of a predetermined minimum allowable range of motion. The apparatus generates an audible alarm in response to the detection of a person's attempt to relocate the personal computer without properly disabling the security software via the keyboard. In addition to the audible alarm that is generated, software resident on the personal computer can obliterate the data stored on the hard disk by reformatting the hard drive to thereby thwart a thief from having access to the data stored on the personal computer.

Inventors

  • 👤 Randall C. McBride

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 09:14
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/02; G08B13/14; G08B13/1409

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 102 words
Apparatus for providing security to prevent unauthorized removal of a personal computer from a location at which the personal computer is resident, comprising: means for monitoring the presence of a reference signal produced by a substantially immutable reference signal source; means for monitoring the presence of a reference signal produced by a substantially immutable reference signal source; means, responsive to said monitoring means determining a variance of said reference signal in excess of a predetermined threshold, for generating an alarm indicating unauthorized movement of said personal computer; and means, responsive to said alarm indication, for activating at least one theft deterrence action.
Claim 2
Dependent Claim 102 words
Apparatus for providing security to prevent unauthorized removal of a personal computer from a location at which the personal computer is resident, comprising: means for monitoring the presence of a reference signal produced by a substantially immutable reference signal source; means for monitoring the presence of a reference signal produced by a substantially immutable reference signal source; means, responsive to said monitoring means determining a variance of said reference signal in excess of a predetermined threshold, for generating an alarm indicating unauthorized movement of said personal computer; and means, responsive to said alarm indication, for activating at least one theft deterrence action.
Claim 3
Dependent Claim 31 words
The apparatus of claim 1 wherein said monitoring means comprises: means for determining the presence of a predetermined voltage present on a telephone line to which said personal computer is connected.
Claim 4
Dependent Claim 39 words
The apparatus of claim 2 wherein said monitoring means further comprises: means for periodically validating said predetermined voltage by generating an off-hook condition on said telephone line to elicit dial tone from telephone company equipment serving said telephone line.
Claim 5
Dependent Claim 41 words
The apparatus of claim 1 wherein said monitoring means comprises: at least one motion sensor mounted within said personal computer for generating a signal indicative of absence of motion in a predetermined plane of reference in excess of a predetermined amount.
Claim 6
Dependent Claim 62 words
The apparatus of claim 1 wherein said monitoring means comprises: means for determining the presence of a predetermined voltage present on a telephone line to which said personal computer is connected; at least one motion sensor mounted within said personal computer for generating a signal indicative of absence of motion in a predetermined plane of reference in excess of a predetermined amount.
Claim 7
Dependent Claim 44 words
The apparatus of claim 5 wherein said alarm generating means comprises: means for verifying a concurrent determined absence of said reference signal for greater than a predetermined period of time from both said predetermined voltage determining means and said at least one motion sensor.
Claim 8
Dependent Claim 16 words
The apparatus of claim 1 wherein said activating means comprises: means for producing an audible alarm.
Claim 9
Dependent Claim 43 words
The apparatus of claim 1 wherein said activating means comprises: means for activating said personal computer to display a query to a user; and means, responsive to a user failing to input a valid response to said query, for producing an audible alarm.
Claim 10
Dependent Claim 22 words
The apparatus of claim 8 wherein said activating means further comprises: means for disabling access to data stored in said personal computer.
Claim 11
Dependent Claim 20 words
The apparatus of claim 9 wherein said disabling access means comprises: means for reformatting memory resident in said personal computer.
Claim 12
Independent Claim 82 words
A method for providing security to prevent unauthorized removal of a personal computer from a location at which the personal computer is resident, comprising the steps of: monitoring the presence of a reference signal produced by a substantially immutable reference signal source; generating, in response to determination of variance of said reference signal in excess of a predetermined threshold, an alarm indicating unauthorized movement of said personal computer; and activating, in response to said alarm indication, at least one theft deterrence action.
Claim 13
Independent Claim 82 words
A method for providing security to prevent unauthorized removal of a personal computer from a location at which the personal computer is resident, comprising the steps of: monitoring the presence of a reference signal produced by a substantially immutable reference signal source; generating, in response to determination of variance of said reference signal in excess of a predetermined threshold, an alarm indicating unauthorized movement of said personal computer; and activating, in response to said alarm indication, at least one theft deterrence action.
Claim 14
Dependent Claim 30 words
The method of claim 11 wherein said step of monitoring comprises: determining the presence of a predetermined voltage present on a telephone line to which said personal computer is connected.
Claim 15
Dependent Claim 38 words
The method of claim 12 wherein said step of monitoring further comprises: periodically validating said predetermined voltage by generating an off-hook condition on said telephone line to elicit dial tone from telephone company equipment serving said telephone line.
Claim 16
Dependent Claim 43 words
The method of claim 11 wherein said step of monitoring comprises: using at least one motion sensor mounted within said personal computer to generate a signal indicative of absence of motion in a predetermined plane of reference in excess of a predetermined amount.
Claim 17
Dependent Claim 62 words
The method of claim 11 wherein said step of monitoring comprises: determining the presence of a predetermined voltage present on a telephone line to which said personal computer is connected; using at least one motion sensor mounted within said personal computer to generate a signal indicative of absence of motion in a predetermined plane of reference in excess of a predetermined amount.
Claim 18
Dependent Claim 44 words
The method of claim 15 wherein said step of alarm generating comprises: verifying a concurrent determined absence of said reference signal for greater than a predetermined period of time from both said step of predetermined voltage determining and said at least one motion sensor.
Claim 19
Dependent Claim 15 words
The method of claim 11 wherein said step of activating comprises: producing an audible alarm.
Claim 20
Dependent Claim 41 words
The method of claim 11 wherein said step of activating comprises: activating said personal computer to display a query to a user; and producing, in response to a user failing to input a valid response to said query, an audible alarm.
Claim 21
Dependent Claim 21 words
The method of claim 18 wherein said step of activating further comprises: disabling access to data stored in said personal computer.
Claim 22
Dependent Claim 19 words
The method of claim 19 wherein said step of disabling access comprises: reformatting memory resident in said personal computer.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-10-06 2001-04-07 2001-10-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-10-06 2005-04-07 2005-10-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-10-06 2009-04-07 2009-10-07 $7700.00 Window Closed / Lapsed

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