WEIGHT SENSITIVE SECURITY SYSTEM

• US 3,750,158 A
• Filed: 06/02/1972
• Issued: 07/31/1973
• Est. Priority Date: 06/02/1972
• Status: Expired due to Term

• Current Assignee: Evangelos M. Anastassakis
• Original Assignee: Evangelos M. Anastassakis
• Inventors: Anastassakis, Evangelos M.
• Primary Examiner(s): Caldwell, John W.
• Assistant Examiner(s): Partridge, Scott F.
• Application Number:
  US05/259,010
• Time in Patent Office: 424 Days
• Field of Search: 340/272,280 200/85R 177/1,245,50 235/91L,92WT 346/94
• US Class Current: 43/59
• CPC Class Codes: G08B 13/1472 with force or weight detection
• CPC Class Codes: Y10S 70/49 with alarm
• CPC Class Codes: Y10T 70/625 Operation and control
• CPC Class Codes: Y10T 70/70 Operating mechanism
• CPC Class Codes: Y10T 70/827 Attention-directing

Abstract

A security system for detection of the unauthorized removal of articles from a controlled area in which the weight of an individual is determined upon entrance into and exit from a controlled area, the difference between entrance and exit weights being employed to determine whether items are being removed. Upon entrance into a controlled area, an individual'"'"''"'"'s weight is determined and a coded card provided indicating the entrance weight. Upon exit from the controlled area, the individual is again weighed and the exit weight compared with the entrance weight decoded from the card by card reading apparatus. The difference in entrance and exit weight is compared with a reference value and upon exceedance of the reference value causes an alarm indication.

Claims

1. A security system comprising:

means for determining the weight of an individual upon entry into a controlled area;

means for providing a first signal representative of said entrance weight;

means for determining the weight of said individual upon exit from said controlled area;

means for providing a second signal representative of said exit weight;

means operative in response to said first and second signals for providing an output signal representing the difference therebetween;

means for providing a reference signal representative of a maximum allowable weight difference between said entrance and exit weights; and

means operative in response to said reference signal and said output signal for providing an alarm indication in the event that said output signal represents a weight difference greater than that represented by said reference signal.

2. A security system according to claim 1 wherein:

said entrance weight determining means includes a scale having a platform on which an individual is disposed for weighing, and means for providing a coded card having a sensible representation of the entrance weight thereon;

said exit weight providing means includes a scale having a platform on which an individual is disposed for weighing; and

said first signal providing means includes means at the exit from said controlled area for reading said coded card and for providing said first signal representative of the entrance weight encoded thereon.

3. A security system according to claim 1 including:

an entrance zone at which said entrance weight is determined, an exit zone at which said exit weight is determined, and an entrance and exit barrier for each of said zones;

means at each of said zones for detecting the entry of an individual therein and the exit of an indivudal therefrom;

means operative upon detection of the presence of an individual in said entrance zone for locking said entrance barrier to prevent entry of another individual while one individual is already present, and for locking said exit barrier to prevent the egress of said individual into said entrance zone until his weight has been determined; and

means operative upon detection of the presence of an individual in said exit zone for locking the entrance barrier thereof to prevent entry of another individual until the individual in said exit zone has left said zone, and for locking the exit barrier of said exit zone to prevent egress of the individual in said exit zone in response to an output signal representing a weight difference greater than said maximum allowable difference.

4. A security system according to claim 1 including:

means for storing representations of the corresponding entrance and exit weights of an individual; and

means operative to provide said first and second signals in response to said stored representations.

5. A security system comprising:

an entrance zone through which individuals must pass for entry into a controlled area, said zone including;

means for determining the weight of an individual upon entry into said controlled area;

means for providing to said individual a coded card having a sensible representation of said entrance weight thereon;

an exit zone through which individuals in said controlled area must pass in leaving said controlled area, said exit zone including;

means for determining the weight of an individual upon exit from said controlled area;

means for providing a first signal representative of said exit weight;

means for sensing said coded card and for providing a second signal representative of the entrance weight decoded therefrom;

means operative in response to said first and second signals for providing an output signal representing the difference therebetween;

means for providing a reference signal representative of a maximum allowable weight difference between said entrance and exit weights; and

means operative in response to said reference signal and said output signal for providing an alarm indication in the event that said output signal represents a weight difference greater than that represented by said reference signal.

6. A security system according to claim 5 wherein said entrance and exit zones each include:

a selectively operable entrance and exit barrier disposed at respective entry and exit positions of said zone;

means for detecting the entry of an individual into said zone and for providing a detection signal in response thereto;

means for detecting the exit of an individual from said zone and for providing a detection signal in response thereto; and

control means operative in response to said detection signals for selectively locking and unlocking said entrance and exit barriers.

7. A security system according to claim 5 wherein said means operative in response to said first and second signals includes a difference circuit operative to provide an output signal having a magnitude representing the difference between the magnitudes of said first and second signals;

and wherein said reference signal responsive means includes a comparator circuit receiving said reference signal and said output signal and operative to provide an alarm signal in the event that said output signal is of a magnitude representing a weight difference greater than that represented by the magnitude of said reference signal.

8. A security system a,cording to claim 7 including counting means operative in response to the presence of each individual at said entrance and exit zones to provide an indication of the number of individuals entering and leaving said controlled area.

9. A security system according to Claim 7 wherein said weight determining means each includes a scale having a platform on which an individual is disposed for weighing.