CA1272266A - Anti-theft product rack and method - Google Patents
Anti-theft product rack and methodInfo
- Publication number
- CA1272266A CA1272266A CA000539541A CA539541A CA1272266A CA 1272266 A CA1272266 A CA 1272266A CA 000539541 A CA000539541 A CA 000539541A CA 539541 A CA539541 A CA 539541A CA 1272266 A CA1272266 A CA 1272266A
- Authority
- CA
- Canada
- Prior art keywords
- rack
- weight
- indication
- alarm
- product units
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47F—SPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS
- A47F10/00—Furniture or installations specially adapted to particular types of service systems, not otherwise provided for
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/02—Mechanical actuation
- G08B13/14—Mechanical actuation by lifting or attempted removal of hand-portable articles
- G08B13/1472—Mechanical actuation by lifting or attempted removal of hand-portable articles with force or weight detection
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07G—REGISTERING THE RECEIPT OF CASH, VALUABLES, OR TOKENS
- G07G1/00—Cash registers
- G07G1/0036—Checkout procedures
- G07G1/0045—Checkout procedures with a code reader for reading of an identifying code of the article to be registered, e.g. barcode reader or radio-frequency identity [RFID] reader
- G07G1/0054—Checkout procedures with a code reader for reading of an identifying code of the article to be registered, e.g. barcode reader or radio-frequency identity [RFID] reader with control of supplementary check-parameters, e.g. weight or number of articles
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07G—REGISTERING THE RECEIPT OF CASH, VALUABLES, OR TOKENS
- G07G3/00—Alarm indicators, e.g. bells
- G07G3/003—Anti-theft control
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Burglar Alarm Systems (AREA)
- Control And Other Processes For Unpacking Of Materials (AREA)
- Confectionery (AREA)
- Display Racks (AREA)
- Audible And Visible Signals (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The anti-theft product rack continuously monitors the weight of the rack including individual product units. When a weight deviation is detected, it is characterized as either a disturbance or as the removal of one or more product units. An alarm is sounded if the rack is continuously disturbed for a pro-grammable number of continuous weight sensing cycles, or if a programmable number of disturbances occur during a programmable period of time. In addition, an alarm is sounded if the number of product units detected as being removed at one time exceeds a programmable limit.
Finally, if the number of detected product units removed exceeds a programmable number during a programmable period of time, an alarm is sounded. The product display rack presents no physical barriers to product removal and requires not intervention of sales personnel for product removal. Thus, the present invention presents an aesthe-tically pleasing product rack while providing a high degree of protection against shoplifting or employee theft.
The anti-theft product rack continuously monitors the weight of the rack including individual product units. When a weight deviation is detected, it is characterized as either a disturbance or as the removal of one or more product units. An alarm is sounded if the rack is continuously disturbed for a pro-grammable number of continuous weight sensing cycles, or if a programmable number of disturbances occur during a programmable period of time. In addition, an alarm is sounded if the number of product units detected as being removed at one time exceeds a programmable limit.
Finally, if the number of detected product units removed exceeds a programmable number during a programmable period of time, an alarm is sounded. The product display rack presents no physical barriers to product removal and requires not intervention of sales personnel for product removal. Thus, the present invention presents an aesthe-tically pleasing product rack while providing a high degree of protection against shoplifting or employee theft.
Description
X~i6 ANTI-TI~EFT P~ODU~r RACK AND MET~IOD
~EC~ICAL FIELD
The invention pertains to anti-theft devices and methods for consurner product racks.
BACKGROUND OF T~E INVEN~ION
A fundamental requirement of product display racks used in a retail enviroslment is that they present the product in an aesthetically pleasing and readily accessible manner in order to promote product sales.
10 However, in order to minimize loss of revenue due to shoplifting, the rack should also provide some means of indicating when products have been removed frorn the rack for the purpose of theft rather than for purchase.
Approaches to the problem of shoplifting from display racks include placing the product behind trans-parent barriers with apertures that are large enough for the human hand but too small to remove a product displayed in the rack. When a consumer chooses a product, he or she is required to request the aid of a salesperson to unlock the transparent barrier allowing removal of the product. The barrier may present an unac-ceptable aesthetic impression of the product which will result in lost sales. ~lso, requiring a customer to request assistance in choosing a product will also result in lost sales.
Often, transparent barriers are provided on display racks which allow stacked products to be removed one at a time from the bottom of the stack. The products are removable only through a slot or the like in the transparent barrier aligned with the bottom of the stack o~ products. Requiring products to be removed only one at a time clearly discourages multiple product purchases.
Other approaches display products on a rack with the products being captured by a slidable retainer or the like. If the slidable retainer is moved without proper authorization, an electrical circuit is inter-rupted and an alarm is sounded. Once again, this display rack requires intervention of a salesperson in order to deactivate the alarm system for legitimate product : '. ' ~: .
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- ~'7~ ;6 removal.
Therefore, product disp]ay racks which provide protection against shoplifting either present an intimidating display by enclosing -the product in a protective barrier, or require the intervention of a salesperson to facilitate legitimate removal of product, or both. These anti-theft features combine to necessarily reduce product sales.
SUMMARY OF THE INVENTION
The present invention aims to avoid the above-identified failings by providing improvements in and relating to product unit racks and corresponding methods. The rack may detect theft while providing absolutely no physical barrier to product removal, ancl while requiring no sales-person intervention for legitimate product removal.
In a representative aspect, the invention providesa method of indicating removal of product units from a product unit rack including the steps of; monitoring a weight of said rack; detecting a disturbance of said rack, according to monitored weight; calculating a number of product units removed from said rack corresponding to a difference in monitored weights before and after said disturbance; and providing an indication of unauthori2ed removal if said number of product units removed from said rack is greater than a limit. Similar methods may indicate theft of product units or disturbance of the rack.
In another representative aspect, the invention provides an anti-theft apparatus for use in a product unit rack or the like. The apparatus includes means for measuring a weight of a group of product units, means responsive to the means for measuring for detecting disturbance of a group of product units, means, responsive to said means for detecting disturbance, for calculating a number of product units removed from said group according to a difference between a measured weight of said group before a detected disturbance and a measured weight of said group after said detected ' :,~
- 2a -disturbance; and means for indicating theft if said number of product units removed from said group exceeds a limit. The invention also provides an anti-theft product unit rack and an apparatus for detecting theft of product units from a group of product units~
According to a feature of the invention, the weight of the display rack is monitored and an alarm is sounded if the sensed weight indicates that more than a programmable number of product units have been removed at one time. In addition, an alarm is sounded if the sensed weight indicates that more than a pro~rammable number of product units have been removed from the display rack within a programmable time period. Also, the present invention is capable of detecting rack tampering such as "swapping" other products for product units in the rack in an attempt to defeat the system. An alarm will occur if the display rack is disturbed continuously for a programmable amount of time, or if a number of unstable episodes not associated with legitimate product removal occur during a programmable time period.
The number of product units that must be removed in order to sound either the instantaneous or periodic alarm is variable, as are the time periods required for periodic removal and for detection of disturbances. Therefore, the present invention is applicable to retail environments having high sales volume or low sales volume by simply reprogramming the various alarm limits.
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The fact the rack of the present invention is alarmed at all can be made completely transparent to the consumer because no physical barriers appear between the consumer and the product. In addition, the product is S not restrained in any way from removal by a le~itimate consumer. Also, intervention of a sales person is not required for the removal of products.
In addition to sounding a local alarm if removal of product units is detected in excess of the 10 program~able limits, the present invention can also sound a remote alarm by wire or radio link. The invention also provides a local acknowledge tone when product units, less in number than the alarm limit, are removed from the rack. The local acknowledge tone notifies the customer that the display is monitored further discouraging theft. The acknowledge tone may be used in addition to or replaced by a synthesized voice which repeats a suit-able salutation upon product removal. The local alarm and acknowledge tone or voice may be silenced so that only the remote alarm sounds.
The display rack can be used with a key lock switch which allows the theft prevention feature of the invention to be disabled for restocking of the rack. The key lock switch may also be used to place the display rack i31 a lock-up mode in which the display rack will cause an alarm if any disturbance of the rack is sensed. This serves to reduce employee theft during periods when a store is closed but employees are present. Finally, the key lock switch may be used to place the display rack in a normal operating mode.
- The key lock switch may be replaced by, or used in addition to, a switch controllable by a real-time clock. The real-time clock controls the switch to modify the various programmable alarm limits, and to automatic-ally place the system in the lock-up mode dependent upon time of day.
The present invention is also applicable to :
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warehouse racks, such as pal~ets and the like, upon which products are stored. The present invention Mllo~s such warehouse racks to be protected from product theft with-out providing expensive anti-theft measures such as lock-able cages, and the like.
It is therefore a prirrlary object of the presentinvention to provide a rack for conswmer product units that reduces loss of revenue due to shoplifting or employee theft, but that does not discourage legitimate product purchases It is another object of this invention to prevent consumer product theft from a product rack by monitoring the weight of the rack holding the consumer products, and by providing an indication, such as an alarm, that a number of product units, in excess of a programmable number of units, have been removed from the rack.
It is yet another object of the present invention to provide a consumer product rack that provides an indication, such as an alarm, that a number of product units, in excess of a programmable number of units, have been removed from the rack during a program-mable time period~
It is also an object of the present invention to deter "swapping" of other merchandise for product units contained in a consumer product rack by providing an indication, such as an alarm, that the rack has been disturbed continuously for more than a programmable time period, or that the rack has experienced A number of 30 disturbances, in excess of a program~able number of dis-turba-nces, during a programmable time period.
These and other objects, features and advantages of the present invention will be seen more clearly by reference to the following detailed specifica-tion and to the appended drawings.
BRIEF DESCRIPTION OF TH~ DRAWINGæ
. . _ Fig. 1 is a~ isometric view of a consumer : .
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product rack according to the present invention.
Fig. 2 is a partial sectional view of the base of the rack shown in Fig. 1, showing the mechanical details of a weight sensor used in the present invention.
Fig. 3 is a block diagram of the electrical schematic of the present invention.
Fig. 4A-4D are a flow chart detailing the computational steps of the theft detection routine of the present invention.
Fig. 5 is a flow chart of the computational steps of the alarm routine of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Fig. 1, a consumer product rack 10 according to the present invention is shown. Rack 10 15 includes a number of individual compartments 11, each compartment holding a plurality of consumer product units 12 such as, for example, cartons of cigarettes. While rack 10 of the preferred embodiment is a display rack intended for placement in a retail establis~ent, it will 20 be understood that the present invention is equally applicable to other product racks, such as warehouse pal~ets, and the like. Rack 10 resets on base 13 which is supported by a plurality of feet as shown in detail in Fig. 2.
Referring to Fig. 2, which is a sectional view of a portion of base 13, the detail of the placement of weight transducers used in the present invention is disclosed. Each transducer 16 is placed between a foot 17 and bracket lS. Bracket 18, in turn, is connected to 30base 13 by appropriate attachment means 19 such as screws or rivets.
In practice, a plurality of weight transducers 16 are placed at a plurality of points beneath base 13 so that the entire weight of rack 10 (Fig. 1) can be 35accurately sensed by the plurality of weight trans-ducers. Each weight transducer is connected to the weight signal processing circuitry of the present inven-~ ,- .., .
.
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tion (shown in detail in Fig. 3) by conductor 21 and connector 22.
Weight transducers 16 are preferably of the highly accurate vibrating wire-type which produce a Yol-tage signal h~ving a frequency which varies in proportionto the weight sensed by the transducer.
Referring to Fig. 3, the hardware embodiment of the present invention is shown. The invention uses a central processing unit (CPU~ 31 to perform the calcula-10 tions and to control the various input/output operationsof the present invention. Processor 31 can be, for example, a type 8031 microcomputer available from Intel Corporation.
Connected to processor 31 are data bus 32 and 15 address bus 33. Buses 32 and 33 allow proeessor 31 to communicate with the various other hardware components of the present invention. Processor 31 communicates with read only memory (ROM) 34 and random access memory (RAM) 36. ROM 34 is used to store the control program of the 20 present invention shown in Figs~ 4A-4D and 5, while RAM
36 is used as a scratch pad memory. ROM 34 can also store the synthesized voice of the acknowledge salutQtion. It should be noted that both ROM 34 and RAM
36 may be located within processor 31, such as, for 25 example, in ~ type 8051 microcomputer available from Intel Corporation.
The individual weight sensors 16 are connected by conductors 21 to respective frequency counters 37 which, in turn are connected to data bus 32 and address 30 bus 33. The individual frequency counters 37 count the frequency of the voltage produced by respective weight sensors 16, and produce a binary word indicative of sensed weight which is placed on data bus 32 when inter-rogated by processor 31 Vifl address bus 33. A $ypical 35 accumulation period for counters 37 is 0.25 seconds. At the end of a particular accu~ulation period, counters 37 Are reset and a new count is begun. Although Fig. 3 . -, -. . .:
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shows only three sets of frequency counters and weight sensors, any number of sensors and counters can be used in the presen$ invention. Frequency counters 37 can be, for example, type ~253 frequency counters manufactured by Intel Corporation.
Also connected to data bus 32 and address 33 is input/output controller 38 which can be, for example, a type 8155 controller available from Intel Corporation.
Controller 38 is connected to ~anged switches Sl and S2 10 which allow a user of the system to program the system for a specific application. Details of this programmability will be discussed below.
Also connected to controller 38 is amplifier 39 which powers alarm speaker 41. Speaker 41 produces both 15 a local acknowledge tone and a local alarm. Alterna-tively, a synthesized voice signal may be stored in ROM
34 and may be played instead of, or in addition to~ the acknowledge tone. The volume of the acknowledge tone or voice is controlled by potentiometer 42, and the volume 20 of the local alarm signal is controlled by potentiometer 43.
The tone and duration of the acknowledge signal and the local alarm are adjustable by use of potentio-meters 45-48. One end of each potentiometers 45-48 is 25 connected to a voltage source + V, and the other ends are grounded. The wiper of each potentiometer is connected to analog-to-digital converter 49 which, in turn, is connected to controller 38. Analog-to-digital converter ~9 can be, for example, a type ADC0844 converter manufac-30 tured by National Semiconductor Corporation.
_ Three positon key lock switch 50 is alsoconnected to controller 38. When switch 50 is in a first position, the display rack is in a normal mode with all features active. In a second position, key lock switch 35 50 disables the theft prevention features of the present invention to allow restocking. Switch 50 can also be positioned in a third position which places the rack in a .:
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night lock-up mode. In the night lock-up mode, any disturbance of the rack will cause an alarm.
Processor 31 is also connected to data output bus 51 which can be used to drive a display or printer 5 (not shown) for the purpose of monitoring the weight of the system or monitoring the disturbance activity or purchase activity of the system. Processor 31 is also connectable to remote alarms 52 through individual links 53. Alarms 52 can be located far from the product 10 display rack for remote monitoring of the system. If desire, the local alarm can be reduced to zero volume and the product display rack can be monitored using only remote alarms 52. Once again, it will be understood that while only two alarms 52 are shown in Fig. 39 this 15 disclosure is offered by way of example rather than limitation and any number of remote alarms may be used.
Linl~s 53 are preferably wire or radio link. A
preferred radio link may use, for example, a type D-24A
.; ~ransmitter 54 and a type D-67 receiver manufactured by ~:` 20 ~inear ~lectronics of Carlsbad, California. Since this preferred transmitter 54 is powered by an internal battery and sends a signal when its control contact is open, this allows an alarm signal to be sent to remote alarms 52 when the display rack becomes unpowered or if 25 the connection between processor 31 and links 53 is severed. Links 53 can also be used to actuate a video camera which will record activity in the vicinity of the protected rack.
If links 53 are wire, elements 5~ in Fig. 3 can 30be appropriate line drivers.
_ Switch Sl, S2 are used by a system operator to manually program various system par~meters as described in detail below. The manual settings of switches Sl and S2 may be overriden by contacts within switch S3. Switch 35S3 is controlled by real-time clock 55. Clock 55, in combination with switch 53 allows one or more of the various parameters to be automatically progral~nable :, . . . .
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-~7~ i6 g dependent upon time o~ day. Clock 55 and switch S3 can also be used to automatically place key-lock switch 50 in the lock-up mode, for example, when a store is closed.
Referring to Figs. 4A-4D, the individual processing steps of the present invention will be described. After the routine is started, the states of switches Sl and S2 are interrogated and parameters K0, Kl, K2, K3 and K5 are set according to the following Tables:
TABLE I
K0: Weight Limit For Instability Sl-7 Limit tlOOths of Units) closed 30 open 40 TABLE II
Kl: Instantaneous Removal Limit Sl-l Sl-2 Sl-3 No. of Product Units closed closed closed open closed closed 2 closed open closed 3 open open closed 4 closed closed open 5 open closed open 6 closed open open 7 open open open 8 TABLE III
j K2: Unstable Episode Limit (C~ V~e cy'~e~) Sl-8 Limit closed lO
open 20 TABLE IV
K3: Periodic Removal Limit Sl-4 Sl-5 Sl-6 No. of Product Units closed closed closed 3 open closed closed 4 closed open closed 5 open open closed 6 , ., ~,' ', ~ '-'' ` :
- ~ ,
~EC~ICAL FIELD
The invention pertains to anti-theft devices and methods for consurner product racks.
BACKGROUND OF T~E INVEN~ION
A fundamental requirement of product display racks used in a retail enviroslment is that they present the product in an aesthetically pleasing and readily accessible manner in order to promote product sales.
10 However, in order to minimize loss of revenue due to shoplifting, the rack should also provide some means of indicating when products have been removed frorn the rack for the purpose of theft rather than for purchase.
Approaches to the problem of shoplifting from display racks include placing the product behind trans-parent barriers with apertures that are large enough for the human hand but too small to remove a product displayed in the rack. When a consumer chooses a product, he or she is required to request the aid of a salesperson to unlock the transparent barrier allowing removal of the product. The barrier may present an unac-ceptable aesthetic impression of the product which will result in lost sales. ~lso, requiring a customer to request assistance in choosing a product will also result in lost sales.
Often, transparent barriers are provided on display racks which allow stacked products to be removed one at a time from the bottom of the stack. The products are removable only through a slot or the like in the transparent barrier aligned with the bottom of the stack o~ products. Requiring products to be removed only one at a time clearly discourages multiple product purchases.
Other approaches display products on a rack with the products being captured by a slidable retainer or the like. If the slidable retainer is moved without proper authorization, an electrical circuit is inter-rupted and an alarm is sounded. Once again, this display rack requires intervention of a salesperson in order to deactivate the alarm system for legitimate product : '. ' ~: .
. . ...
', :': ', - :
- ~'7~ ;6 removal.
Therefore, product disp]ay racks which provide protection against shoplifting either present an intimidating display by enclosing -the product in a protective barrier, or require the intervention of a salesperson to facilitate legitimate removal of product, or both. These anti-theft features combine to necessarily reduce product sales.
SUMMARY OF THE INVENTION
The present invention aims to avoid the above-identified failings by providing improvements in and relating to product unit racks and corresponding methods. The rack may detect theft while providing absolutely no physical barrier to product removal, ancl while requiring no sales-person intervention for legitimate product removal.
In a representative aspect, the invention providesa method of indicating removal of product units from a product unit rack including the steps of; monitoring a weight of said rack; detecting a disturbance of said rack, according to monitored weight; calculating a number of product units removed from said rack corresponding to a difference in monitored weights before and after said disturbance; and providing an indication of unauthori2ed removal if said number of product units removed from said rack is greater than a limit. Similar methods may indicate theft of product units or disturbance of the rack.
In another representative aspect, the invention provides an anti-theft apparatus for use in a product unit rack or the like. The apparatus includes means for measuring a weight of a group of product units, means responsive to the means for measuring for detecting disturbance of a group of product units, means, responsive to said means for detecting disturbance, for calculating a number of product units removed from said group according to a difference between a measured weight of said group before a detected disturbance and a measured weight of said group after said detected ' :,~
- 2a -disturbance; and means for indicating theft if said number of product units removed from said group exceeds a limit. The invention also provides an anti-theft product unit rack and an apparatus for detecting theft of product units from a group of product units~
According to a feature of the invention, the weight of the display rack is monitored and an alarm is sounded if the sensed weight indicates that more than a programmable number of product units have been removed at one time. In addition, an alarm is sounded if the sensed weight indicates that more than a pro~rammable number of product units have been removed from the display rack within a programmable time period. Also, the present invention is capable of detecting rack tampering such as "swapping" other products for product units in the rack in an attempt to defeat the system. An alarm will occur if the display rack is disturbed continuously for a programmable amount of time, or if a number of unstable episodes not associated with legitimate product removal occur during a programmable time period.
The number of product units that must be removed in order to sound either the instantaneous or periodic alarm is variable, as are the time periods required for periodic removal and for detection of disturbances. Therefore, the present invention is applicable to retail environments having high sales volume or low sales volume by simply reprogramming the various alarm limits.
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The fact the rack of the present invention is alarmed at all can be made completely transparent to the consumer because no physical barriers appear between the consumer and the product. In addition, the product is S not restrained in any way from removal by a le~itimate consumer. Also, intervention of a sales person is not required for the removal of products.
In addition to sounding a local alarm if removal of product units is detected in excess of the 10 program~able limits, the present invention can also sound a remote alarm by wire or radio link. The invention also provides a local acknowledge tone when product units, less in number than the alarm limit, are removed from the rack. The local acknowledge tone notifies the customer that the display is monitored further discouraging theft. The acknowledge tone may be used in addition to or replaced by a synthesized voice which repeats a suit-able salutation upon product removal. The local alarm and acknowledge tone or voice may be silenced so that only the remote alarm sounds.
The display rack can be used with a key lock switch which allows the theft prevention feature of the invention to be disabled for restocking of the rack. The key lock switch may also be used to place the display rack i31 a lock-up mode in which the display rack will cause an alarm if any disturbance of the rack is sensed. This serves to reduce employee theft during periods when a store is closed but employees are present. Finally, the key lock switch may be used to place the display rack in a normal operating mode.
- The key lock switch may be replaced by, or used in addition to, a switch controllable by a real-time clock. The real-time clock controls the switch to modify the various programmable alarm limits, and to automatic-ally place the system in the lock-up mode dependent upon time of day.
The present invention is also applicable to :
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warehouse racks, such as pal~ets and the like, upon which products are stored. The present invention Mllo~s such warehouse racks to be protected from product theft with-out providing expensive anti-theft measures such as lock-able cages, and the like.
It is therefore a prirrlary object of the presentinvention to provide a rack for conswmer product units that reduces loss of revenue due to shoplifting or employee theft, but that does not discourage legitimate product purchases It is another object of this invention to prevent consumer product theft from a product rack by monitoring the weight of the rack holding the consumer products, and by providing an indication, such as an alarm, that a number of product units, in excess of a programmable number of units, have been removed from the rack.
It is yet another object of the present invention to provide a consumer product rack that provides an indication, such as an alarm, that a number of product units, in excess of a programmable number of units, have been removed from the rack during a program-mable time period~
It is also an object of the present invention to deter "swapping" of other merchandise for product units contained in a consumer product rack by providing an indication, such as an alarm, that the rack has been disturbed continuously for more than a programmable time period, or that the rack has experienced A number of 30 disturbances, in excess of a program~able number of dis-turba-nces, during a programmable time period.
These and other objects, features and advantages of the present invention will be seen more clearly by reference to the following detailed specifica-tion and to the appended drawings.
BRIEF DESCRIPTION OF TH~ DRAWINGæ
. . _ Fig. 1 is a~ isometric view of a consumer : .
,:
. . .
:, .-., ,~.
{~
product rack according to the present invention.
Fig. 2 is a partial sectional view of the base of the rack shown in Fig. 1, showing the mechanical details of a weight sensor used in the present invention.
Fig. 3 is a block diagram of the electrical schematic of the present invention.
Fig. 4A-4D are a flow chart detailing the computational steps of the theft detection routine of the present invention.
Fig. 5 is a flow chart of the computational steps of the alarm routine of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Fig. 1, a consumer product rack 10 according to the present invention is shown. Rack 10 15 includes a number of individual compartments 11, each compartment holding a plurality of consumer product units 12 such as, for example, cartons of cigarettes. While rack 10 of the preferred embodiment is a display rack intended for placement in a retail establis~ent, it will 20 be understood that the present invention is equally applicable to other product racks, such as warehouse pal~ets, and the like. Rack 10 resets on base 13 which is supported by a plurality of feet as shown in detail in Fig. 2.
Referring to Fig. 2, which is a sectional view of a portion of base 13, the detail of the placement of weight transducers used in the present invention is disclosed. Each transducer 16 is placed between a foot 17 and bracket lS. Bracket 18, in turn, is connected to 30base 13 by appropriate attachment means 19 such as screws or rivets.
In practice, a plurality of weight transducers 16 are placed at a plurality of points beneath base 13 so that the entire weight of rack 10 (Fig. 1) can be 35accurately sensed by the plurality of weight trans-ducers. Each weight transducer is connected to the weight signal processing circuitry of the present inven-~ ,- .., .
.
~L~t?~
tion (shown in detail in Fig. 3) by conductor 21 and connector 22.
Weight transducers 16 are preferably of the highly accurate vibrating wire-type which produce a Yol-tage signal h~ving a frequency which varies in proportionto the weight sensed by the transducer.
Referring to Fig. 3, the hardware embodiment of the present invention is shown. The invention uses a central processing unit (CPU~ 31 to perform the calcula-10 tions and to control the various input/output operationsof the present invention. Processor 31 can be, for example, a type 8031 microcomputer available from Intel Corporation.
Connected to processor 31 are data bus 32 and 15 address bus 33. Buses 32 and 33 allow proeessor 31 to communicate with the various other hardware components of the present invention. Processor 31 communicates with read only memory (ROM) 34 and random access memory (RAM) 36. ROM 34 is used to store the control program of the 20 present invention shown in Figs~ 4A-4D and 5, while RAM
36 is used as a scratch pad memory. ROM 34 can also store the synthesized voice of the acknowledge salutQtion. It should be noted that both ROM 34 and RAM
36 may be located within processor 31, such as, for 25 example, in ~ type 8051 microcomputer available from Intel Corporation.
The individual weight sensors 16 are connected by conductors 21 to respective frequency counters 37 which, in turn are connected to data bus 32 and address 30 bus 33. The individual frequency counters 37 count the frequency of the voltage produced by respective weight sensors 16, and produce a binary word indicative of sensed weight which is placed on data bus 32 when inter-rogated by processor 31 Vifl address bus 33. A $ypical 35 accumulation period for counters 37 is 0.25 seconds. At the end of a particular accu~ulation period, counters 37 Are reset and a new count is begun. Although Fig. 3 . -, -. . .:
'; " ' ' ~ ~
. .
::
shows only three sets of frequency counters and weight sensors, any number of sensors and counters can be used in the presen$ invention. Frequency counters 37 can be, for example, type ~253 frequency counters manufactured by Intel Corporation.
Also connected to data bus 32 and address 33 is input/output controller 38 which can be, for example, a type 8155 controller available from Intel Corporation.
Controller 38 is connected to ~anged switches Sl and S2 10 which allow a user of the system to program the system for a specific application. Details of this programmability will be discussed below.
Also connected to controller 38 is amplifier 39 which powers alarm speaker 41. Speaker 41 produces both 15 a local acknowledge tone and a local alarm. Alterna-tively, a synthesized voice signal may be stored in ROM
34 and may be played instead of, or in addition to~ the acknowledge tone. The volume of the acknowledge tone or voice is controlled by potentiometer 42, and the volume 20 of the local alarm signal is controlled by potentiometer 43.
The tone and duration of the acknowledge signal and the local alarm are adjustable by use of potentio-meters 45-48. One end of each potentiometers 45-48 is 25 connected to a voltage source + V, and the other ends are grounded. The wiper of each potentiometer is connected to analog-to-digital converter 49 which, in turn, is connected to controller 38. Analog-to-digital converter ~9 can be, for example, a type ADC0844 converter manufac-30 tured by National Semiconductor Corporation.
_ Three positon key lock switch 50 is alsoconnected to controller 38. When switch 50 is in a first position, the display rack is in a normal mode with all features active. In a second position, key lock switch 35 50 disables the theft prevention features of the present invention to allow restocking. Switch 50 can also be positioned in a third position which places the rack in a .:
,. . :; .
~L~7~
night lock-up mode. In the night lock-up mode, any disturbance of the rack will cause an alarm.
Processor 31 is also connected to data output bus 51 which can be used to drive a display or printer 5 (not shown) for the purpose of monitoring the weight of the system or monitoring the disturbance activity or purchase activity of the system. Processor 31 is also connectable to remote alarms 52 through individual links 53. Alarms 52 can be located far from the product 10 display rack for remote monitoring of the system. If desire, the local alarm can be reduced to zero volume and the product display rack can be monitored using only remote alarms 52. Once again, it will be understood that while only two alarms 52 are shown in Fig. 39 this 15 disclosure is offered by way of example rather than limitation and any number of remote alarms may be used.
Linl~s 53 are preferably wire or radio link. A
preferred radio link may use, for example, a type D-24A
.; ~ransmitter 54 and a type D-67 receiver manufactured by ~:` 20 ~inear ~lectronics of Carlsbad, California. Since this preferred transmitter 54 is powered by an internal battery and sends a signal when its control contact is open, this allows an alarm signal to be sent to remote alarms 52 when the display rack becomes unpowered or if 25 the connection between processor 31 and links 53 is severed. Links 53 can also be used to actuate a video camera which will record activity in the vicinity of the protected rack.
If links 53 are wire, elements 5~ in Fig. 3 can 30be appropriate line drivers.
_ Switch Sl, S2 are used by a system operator to manually program various system par~meters as described in detail below. The manual settings of switches Sl and S2 may be overriden by contacts within switch S3. Switch 35S3 is controlled by real-time clock 55. Clock 55, in combination with switch 53 allows one or more of the various parameters to be automatically progral~nable :, . . . .
' ~ ~
-~7~ i6 g dependent upon time o~ day. Clock 55 and switch S3 can also be used to automatically place key-lock switch 50 in the lock-up mode, for example, when a store is closed.
Referring to Figs. 4A-4D, the individual processing steps of the present invention will be described. After the routine is started, the states of switches Sl and S2 are interrogated and parameters K0, Kl, K2, K3 and K5 are set according to the following Tables:
TABLE I
K0: Weight Limit For Instability Sl-7 Limit tlOOths of Units) closed 30 open 40 TABLE II
Kl: Instantaneous Removal Limit Sl-l Sl-2 Sl-3 No. of Product Units closed closed closed open closed closed 2 closed open closed 3 open open closed 4 closed closed open 5 open closed open 6 closed open open 7 open open open 8 TABLE III
j K2: Unstable Episode Limit (C~ V~e cy'~e~) Sl-8 Limit closed lO
open 20 TABLE IV
K3: Periodic Removal Limit Sl-4 Sl-5 Sl-6 No. of Product Units closed closed closed 3 open closed closed 4 closed open closed 5 open open closed 6 , ., ~,' ', ~ '-'' ` :
- ~ ,
2~
closed closed open 7 open closed open 8 closed open open g open open open lO
TABLE V
K5: Time Period S _ S2-5 S2-6 Time (min.) closed closed closed open closed closed 2 closed open closed 3 open open closed 4 closed closed open 5 open closed open 6 closed open open 7 open open open 8 In the present embodiment, parameter K4, which is the periodic unstable episode limit is set equal to 5O However, this limit could also be programmable with the addition of additional switches.
The remaining switches ~1-3 of S2) are used to designate the number of weight transducers on a partic-ular display rack. This allows the same theft detec$ion hardware to be applied to various sizes of racks using various numbers of weight transducers. Also, it allows 25 the system to detect if a weight transducer has been dis-connected. The number of valid transducers is set according to $he following Table.
TABLE Vl Valid Transducers S2-1 S2-2 S2-3 Valid Tranducers _ closed closed closed tone test open closed closed closed open closed l, 2 open open closed l, 2, 3 closed closed open l, 2; 3, 4 open closed open l, 2, 3, 4, 5 closed open open l, 2, 3, 4, 5, 6 ~, open open open invalid setting When switches S2-1, S2-2 and S2-3 are all closed, the local alarm or voice is turned on thereby allowing the tone and volume to be set as described earlier. When switches S2-1, S2-2 and S2-3 are all open, this state is ignored as an invalid setting. Therefore, according to the pre~erred embodiment, at least one and up to six weight transducers may be used. Once again, this should not be considered a limitation of the present 10 invention. Additional transdlucers can be obviously accommodated ~y adding additional switches.
-After the parameters are set by interrogation of switches Sl and S2 in block 56, control is transferred to block 57 where the first weight reading9 WTRDGl, is 15 taken. The weight is determined by interrogating the individual weight sensors 16 via frequency counters 37 (both shown in Fig. 3), and by summing the individual sensed weights. In this manner, the entire weight of the display rack is sensed. The units of variable WTRDGl are 20 in 100ths of product units. Therefore the actual weight sensed by sensors 16 must be multiplied by a predeter-mined factor in order to convert the actual sensed weight into a weight in 100ths of product units. If, when taking ~eight reading WTGRDGI, the system detects weight 25 signals are being produced by less than the number of transducers set by switches S2-1, ~2-2 and S2-3 according to Table VI, an alarm is sounded.
Control is then transferred to block 58 where variables WTRDG2, WTRDG3 and P~EWT are all set to ~TRDGl.
30The program then enters the main loop of the routine beginning with block 59 where, with operation identical to that of block 57, the weight WTRDGl is again sensed, and it is determined if the nunber of transducers is less than that indicated by switches S2-1, S2-2 and 35 S2-3 according to Table Vl. Control is then transferred to block 61 Yhere cycle counter CYCLCNT is incremented by 1 and counter OLDCYCL is set equal to counter CYCLCNT
.
.
.
~2~
less K5.
Control is then transferred to motion detection decision blocks 62-64. In these decision blocks, the three stored weight readings WTRDGl, corresponding to the S present weight, WTRDG2, corresponding to the last sensed weight, and WTRDG3, corresponding to the penultimate sensed weight, are each subtracted and the differences are compared with parameter K0. If the difference between any two of the sensed weights is greater than 10 parameter K0, flat MOTFLAGl is set equal to "l" in block 66. Otherwise, flag MOTFLAGl is set equal to "0" in block 67. Control is then transferred to decision block 68 where the state of MOTFLAGl is detected. If flag MOT~LAGl was set in block 66, counter MDTCNT is incre-15 mented by l in block 69. Otherwise, counter MOTCNT isset to 0 in block 71. Counter MOTCNT keeps track of the number of consecutive cycles wherein motion is detected.
The value of counter MOTCNT is compared with 20 parameter K2 in decision block 72. If counter MDTCNT is greater than parameter K2, indicating that the number of consecutive unstable episodes is greater than the desired limit, control is transferred to block 73 where variable ALARM is set equal to "2", counter MOTCNT is reset in 25 block 74 and the alarm is sounded in block 76 (processing steps described in detail with reference to Fig. 5).
This ends $he motion detection portion of the routine.
Control is then transferred to decision block 77 where detect;on of the nwnber of product units removed 30 is begun. In block 78, variable PR~WT is set equal to the last sensed weigh~, WTRDG2, if M~TFLAGl is equal to "1" and if flag MOTFLAG2 is equal to "0" as determined in decision block 77. In other words, decision block 77 determines if motion is detected during the present cycle 35 when none was detected during the previous cycle.
Control is then transferred to decision block 79 where it is determined if no motion WAS detected 6~;
during the present cycle, but that motion was detected during the previous cycle. This is accomplished in decision bloek 79 which interrogates flags MOTFLAGl and MOTFLAG2. If true, control is transferred to block 8l where the integer number of product units removed is determined by the rounding formula shown. Using this formula, weights less than 0.49 units are rounded down, weights between 0.50 and 1.49 units are rounded to l, and so forth. Control is then transferred to decision block 10 82 where it is determined if any product units were removed. If so, the local acknowledge tone is sounded, or the stored synthesized voice is played back, in block 83 and control is transferred to block 84 to determine if the number of product units removed is greater than 15 parameter Kl. In other words, block 84 determines if the detected number of units removed from the rack is greater than the instantaneous removal limit. If so, control is transferred to block 86 where variable ALARM is set equal to "l" and the alarm is sounded in block 87. This ends 20 the instantaneous removal detection portion of the routine.
Control is then transferred to block 88 where the routine for determining the number of unstable epi-sodes occuring during time period K5 is determined. In 25 block 88, counter N is set equal to 1'0ll and control is transferred to a loop beginning with block 89 where counter N is incremented.
In decision block 9l, all entries in motion vector MOTPER(N) are discarded if the entries are greater 30 than counter OLDCYCL. Motion vector MOTPER(N) is a time stamp vector in which the individual entries record the cycle number when motion was detected when that motion was determined not to be a removal of an integer number of product units.
By this means, only time stamps less than ~5 old are retained in vector M~TPER(N). Counter N is incremented in block 93 and the checking loop is i6 traversed until N equals 10. It should be emphasized that although only 10 time stamps are retained in vector MOTPER(N), this is once again by way of example only and not by way of limitation.
Control is then transferred to decision block 94 where if there has been no motion detected during the present cycle and if there was motion detected during the past cycle, and if the number o;E product units removed is less than 1, control is transferred to block 95 where 10 counter N is set equal to "0". In the loop beginning with block 96, counter N is incremented and consecutive entries of vector MOTPER(N) are interrogated and deter-mined if equal to 0 in block 97. When the first 0 element is detected, control is transferred to block 98 15 where the individual element of MOTPER~N) is set equal to the present cycle, CYCLCNT, in block 98 thereby recording a time stamp of the detected motion. The loop including block 97 is not exited unless a ~ero element is found in vector MOTPER(N), or unless the end of the vector is 20 detected in decision block 99.
Control is then transferred to block 101 where counters Q and N are both set equal to "0" and another ehecking loop is entered. In this loop, counter N is incremented in block 102 and individual entries of vector 25 MOTPER(N) are interrogated by decision block 103. If any entry is greater than 0, counter Q is incremented by 1 in block 104. The loop is retraced until the end of vector MOTPER(N) is detected in decision block 106. Thus, counter Q is set equal $o the number of non-zero entries 30 in motion vector MOTP~R(N~.
- Control is then transferred to decision block 107 where it is determined if counter Q is greater than parameter K4. If so, control is transferred to block 108 where variable ALARM is set equal to "4" and the alarm is 35 sounded in block 109. In other words, the alarm is sounded if counter Q indicates th~t there has been a number of unstable episodes greater than parameter K4 "':
~, . ..
during a period set b~ parameter I~5. This ends the peri-odic unstable episode detection portion of the routine.
Control is then transferred to block 111 where counter N is set equal to 0. Block 111 begins a routine which detects the number of product units removed during a time period set by parameter K5.
In block 112, counter N is incremented and a loop is started in which the individual entries of counter vector CNTREM(N) that are greater than counter 10 OLDCYCL (as determined by decision block 113), are set equal to 0 in block 114. Count vector CNTREM(N), similar in format to motion vector MOTPER(N), is a time stamp vector in which the individual entries record the cycle number when each product unit was removed. The loop is 15 retraced until all entries of vector CNTREM(N) have been interrogated as determined by decision block 116. After this loop, all entries of counter vector CNTREM(N) will be set to 0 if the counts are equal to counter OLDCYCL
(i.e., older than time period K5). In decision block 117 20 it is determined if any product units have been removed by interrogation of counter CNTREM. If not, no further action is taken and control is transferred to block 118 (Fig. 4D). If true, control is transferred to block 119 where counter N is set equal to "0" and a loop is begun 25 with block 121 where counter N is incremented.
In the loop beginning with block 121, count vector CNTREM(N) is interrogated for 0 entries in block 122, and counter CNTREM is compared with "0". If a zero entry is detected and if CNTREM is greater than zero, 30 control is transferred to block 123 where the vector entry detected as 0 in block 122 is set equal to counter CYCL~NT, and counter CNTREM is decremented by 1. The interrogation loop is continued until decision block 1~4 determines that the last entry in count vector CNTREM(N) 35 has been interrogated. As a result of this loop, time stamps equal to the present cycle count are entered into vector CNTREM(N~ for each product unit removedO It should be noted that'if more than one product unit is detected as being removed during a single cycle, several of the entries in count vector CNTREM(N) will have the same value.
Control is then transferred to block 126 where counter Q and N are both reset. In block 127, counter N
is incremented and a loop is begun wherein the individual entries of counter vector CNTREM(N) are interrogated in decision block 128. For each non-zero entry in vector 10 CNTREM(N), counter Q is incremented by 1 in block 129.
The loop is retraced until decision block 131 determines that each element of vector CNTREM(N) has been inter-rogated. As a result of this loop, counter Q indicates the number of non-zero entries in count vector CNTREM(N).
In decision block 132, counter Q is compared with parameter K3 to determine if the periodic unit removal limit has been exceeded. If so, variable ALARM
is set equal to "3" in block 133 and the alarm is sounded in block 134. Control is then transferred to block 118 20 where the flag MOTFLAG2 is updated as are weight readings WTRDG3 and WTRDG2. Control is then transferred back to block 136 (Fig. 4A) where the loop is once again begun.
Referring back to Fig. 4A, in block 136J which operates identically to block 56, the states of switches 25 Sl and S2 are again sensed. This is in order to detect any changes in the states of switches 51 and 52 under action of switch 53 (Eig. 3).
Next decision blocks 137, 139 and 140 are used to detect the positon of key-lock switch 50 (Fig. 3~. If 30 key-lock switch 50 is in the lock-up mode (or if switch 53 has placed key-lock switch 50 in the lock-up mode), block 137 directs control to block 138 where appropriate parameters are minimized in order to place the rack at its highest theft prevention sensitivity. Control is 35 then transferred to block 59 where the entire loop is retraced.
If block 139 does not detect lock-up, control - :: -2~,~
is transferred to block 138 where normal mode is detected. If key lock switch 50 is in the normal mode positon, control is transferred to block 59, and the loop is retraced.
If block 139 decides key lock switch 50 is not in the normal mode, control is transferred to decision block 140 where, if key lock switch 50 is in the restock mode, block 136 is again reentered without retracing the main loop. Otherwise, the rnain loop is retraced by entering block 59.
Referring now to Fig. 5, the alarm routine will be described. In block 141, it is determined if variable ALAR~ is equal to "3" or "4". If not, control is trans-ferred immediately to block 146. If so, counter N is reset in block 142, and a loop comprising blocks 143-145 is traversed a sufficient number of times to reset all entries of vectors CNT~EM(N) and M~TPER(N). Then the alarm is sounded in block 146.
In summary, switches S2-1, S2-2 and S2-3 are positioned by the user of the system as shown in Table VI
to accom~odate the number of weight transducers in the rack in use. Parameter Kl, the instantaneous removal limit, is set by positioning switches Sl-l, Sl-2 and Sl-3 as shown in Table II, and is variable from 1 to 8 product ~5 units.
Switches Sl-4, Sl-5 and Sl-6 are used to set the number of product units which must be removed over a time period to cause an alarm. This is called the perio-dic removal limit, K3, and is adjustable from 3 to 10 product units as shown in Table IV. The time period, K5, for-the periodic removal limit is set by positioning switches S2-4, S2-5 and S2-6, as shown in Table V. In addition, an alarm will sound if the display rack is disturbed continuously for a number of cycles settable by switch Sl-8 (parameter K2) as shown in Table III.
Finally, rack tampering or "swapping" of other ~erch~nd-ise ~or product units contained In the rack is dete~ted ` ' ~
: .
if five unstable episodes (parameter K~) occur within the time period set by parameter K5.
The product rack will acknowledge removal of product units (when not in excess of an alarm limit) by S an adjustable local tone or synthesized voice which can be set to %ero volume. The separately adjustable local alarm tone can also be set to zero volume if local alarm is not desired. The alarm signal can be transmitted to a remote receiver, over wire or radio link, which will sound an alarm at a remote location. The local tones are both adjustable in volume, tone and duration.
A principal factor in determining how restrictive the various programmable alarm criteria for periodic removal should be is the extent to which legiti-mate purchases cause false alarms. This would of courseoccur during peak $raffic hours. The following is a table displaying the results of a computer simulation which was based on the following assumptions:
1. During peak traffic hours, ten customers remove one product unit and five customers remove two product units for total sales of 20 product units during a peak hour.
2. The purchases occur at random times.
closed closed open 7 open closed open 8 closed open open g open open open lO
TABLE V
K5: Time Period S _ S2-5 S2-6 Time (min.) closed closed closed open closed closed 2 closed open closed 3 open open closed 4 closed closed open 5 open closed open 6 closed open open 7 open open open 8 In the present embodiment, parameter K4, which is the periodic unstable episode limit is set equal to 5O However, this limit could also be programmable with the addition of additional switches.
The remaining switches ~1-3 of S2) are used to designate the number of weight transducers on a partic-ular display rack. This allows the same theft detec$ion hardware to be applied to various sizes of racks using various numbers of weight transducers. Also, it allows 25 the system to detect if a weight transducer has been dis-connected. The number of valid transducers is set according to $he following Table.
TABLE Vl Valid Transducers S2-1 S2-2 S2-3 Valid Tranducers _ closed closed closed tone test open closed closed closed open closed l, 2 open open closed l, 2, 3 closed closed open l, 2; 3, 4 open closed open l, 2, 3, 4, 5 closed open open l, 2, 3, 4, 5, 6 ~, open open open invalid setting When switches S2-1, S2-2 and S2-3 are all closed, the local alarm or voice is turned on thereby allowing the tone and volume to be set as described earlier. When switches S2-1, S2-2 and S2-3 are all open, this state is ignored as an invalid setting. Therefore, according to the pre~erred embodiment, at least one and up to six weight transducers may be used. Once again, this should not be considered a limitation of the present 10 invention. Additional transdlucers can be obviously accommodated ~y adding additional switches.
-After the parameters are set by interrogation of switches Sl and S2 in block 56, control is transferred to block 57 where the first weight reading9 WTRDGl, is 15 taken. The weight is determined by interrogating the individual weight sensors 16 via frequency counters 37 (both shown in Fig. 3), and by summing the individual sensed weights. In this manner, the entire weight of the display rack is sensed. The units of variable WTRDGl are 20 in 100ths of product units. Therefore the actual weight sensed by sensors 16 must be multiplied by a predeter-mined factor in order to convert the actual sensed weight into a weight in 100ths of product units. If, when taking ~eight reading WTGRDGI, the system detects weight 25 signals are being produced by less than the number of transducers set by switches S2-1, ~2-2 and S2-3 according to Table VI, an alarm is sounded.
Control is then transferred to block 58 where variables WTRDG2, WTRDG3 and P~EWT are all set to ~TRDGl.
30The program then enters the main loop of the routine beginning with block 59 where, with operation identical to that of block 57, the weight WTRDGl is again sensed, and it is determined if the nunber of transducers is less than that indicated by switches S2-1, S2-2 and 35 S2-3 according to Table Vl. Control is then transferred to block 61 Yhere cycle counter CYCLCNT is incremented by 1 and counter OLDCYCL is set equal to counter CYCLCNT
.
.
.
~2~
less K5.
Control is then transferred to motion detection decision blocks 62-64. In these decision blocks, the three stored weight readings WTRDGl, corresponding to the S present weight, WTRDG2, corresponding to the last sensed weight, and WTRDG3, corresponding to the penultimate sensed weight, are each subtracted and the differences are compared with parameter K0. If the difference between any two of the sensed weights is greater than 10 parameter K0, flat MOTFLAGl is set equal to "l" in block 66. Otherwise, flag MOTFLAGl is set equal to "0" in block 67. Control is then transferred to decision block 68 where the state of MOTFLAGl is detected. If flag MOT~LAGl was set in block 66, counter MDTCNT is incre-15 mented by l in block 69. Otherwise, counter MOTCNT isset to 0 in block 71. Counter MOTCNT keeps track of the number of consecutive cycles wherein motion is detected.
The value of counter MOTCNT is compared with 20 parameter K2 in decision block 72. If counter MDTCNT is greater than parameter K2, indicating that the number of consecutive unstable episodes is greater than the desired limit, control is transferred to block 73 where variable ALARM is set equal to "2", counter MOTCNT is reset in 25 block 74 and the alarm is sounded in block 76 (processing steps described in detail with reference to Fig. 5).
This ends $he motion detection portion of the routine.
Control is then transferred to decision block 77 where detect;on of the nwnber of product units removed 30 is begun. In block 78, variable PR~WT is set equal to the last sensed weigh~, WTRDG2, if M~TFLAGl is equal to "1" and if flag MOTFLAG2 is equal to "0" as determined in decision block 77. In other words, decision block 77 determines if motion is detected during the present cycle 35 when none was detected during the previous cycle.
Control is then transferred to decision block 79 where it is determined if no motion WAS detected 6~;
during the present cycle, but that motion was detected during the previous cycle. This is accomplished in decision bloek 79 which interrogates flags MOTFLAGl and MOTFLAG2. If true, control is transferred to block 8l where the integer number of product units removed is determined by the rounding formula shown. Using this formula, weights less than 0.49 units are rounded down, weights between 0.50 and 1.49 units are rounded to l, and so forth. Control is then transferred to decision block 10 82 where it is determined if any product units were removed. If so, the local acknowledge tone is sounded, or the stored synthesized voice is played back, in block 83 and control is transferred to block 84 to determine if the number of product units removed is greater than 15 parameter Kl. In other words, block 84 determines if the detected number of units removed from the rack is greater than the instantaneous removal limit. If so, control is transferred to block 86 where variable ALARM is set equal to "l" and the alarm is sounded in block 87. This ends 20 the instantaneous removal detection portion of the routine.
Control is then transferred to block 88 where the routine for determining the number of unstable epi-sodes occuring during time period K5 is determined. In 25 block 88, counter N is set equal to 1'0ll and control is transferred to a loop beginning with block 89 where counter N is incremented.
In decision block 9l, all entries in motion vector MOTPER(N) are discarded if the entries are greater 30 than counter OLDCYCL. Motion vector MOTPER(N) is a time stamp vector in which the individual entries record the cycle number when motion was detected when that motion was determined not to be a removal of an integer number of product units.
By this means, only time stamps less than ~5 old are retained in vector M~TPER(N). Counter N is incremented in block 93 and the checking loop is i6 traversed until N equals 10. It should be emphasized that although only 10 time stamps are retained in vector MOTPER(N), this is once again by way of example only and not by way of limitation.
Control is then transferred to decision block 94 where if there has been no motion detected during the present cycle and if there was motion detected during the past cycle, and if the number o;E product units removed is less than 1, control is transferred to block 95 where 10 counter N is set equal to "0". In the loop beginning with block 96, counter N is incremented and consecutive entries of vector MOTPER(N) are interrogated and deter-mined if equal to 0 in block 97. When the first 0 element is detected, control is transferred to block 98 15 where the individual element of MOTPER~N) is set equal to the present cycle, CYCLCNT, in block 98 thereby recording a time stamp of the detected motion. The loop including block 97 is not exited unless a ~ero element is found in vector MOTPER(N), or unless the end of the vector is 20 detected in decision block 99.
Control is then transferred to block 101 where counters Q and N are both set equal to "0" and another ehecking loop is entered. In this loop, counter N is incremented in block 102 and individual entries of vector 25 MOTPER(N) are interrogated by decision block 103. If any entry is greater than 0, counter Q is incremented by 1 in block 104. The loop is retraced until the end of vector MOTPER(N) is detected in decision block 106. Thus, counter Q is set equal $o the number of non-zero entries 30 in motion vector MOTP~R(N~.
- Control is then transferred to decision block 107 where it is determined if counter Q is greater than parameter K4. If so, control is transferred to block 108 where variable ALARM is set equal to "4" and the alarm is 35 sounded in block 109. In other words, the alarm is sounded if counter Q indicates th~t there has been a number of unstable episodes greater than parameter K4 "':
~, . ..
during a period set b~ parameter I~5. This ends the peri-odic unstable episode detection portion of the routine.
Control is then transferred to block 111 where counter N is set equal to 0. Block 111 begins a routine which detects the number of product units removed during a time period set by parameter K5.
In block 112, counter N is incremented and a loop is started in which the individual entries of counter vector CNTREM(N) that are greater than counter 10 OLDCYCL (as determined by decision block 113), are set equal to 0 in block 114. Count vector CNTREM(N), similar in format to motion vector MOTPER(N), is a time stamp vector in which the individual entries record the cycle number when each product unit was removed. The loop is 15 retraced until all entries of vector CNTREM(N) have been interrogated as determined by decision block 116. After this loop, all entries of counter vector CNTREM(N) will be set to 0 if the counts are equal to counter OLDCYCL
(i.e., older than time period K5). In decision block 117 20 it is determined if any product units have been removed by interrogation of counter CNTREM. If not, no further action is taken and control is transferred to block 118 (Fig. 4D). If true, control is transferred to block 119 where counter N is set equal to "0" and a loop is begun 25 with block 121 where counter N is incremented.
In the loop beginning with block 121, count vector CNTREM(N) is interrogated for 0 entries in block 122, and counter CNTREM is compared with "0". If a zero entry is detected and if CNTREM is greater than zero, 30 control is transferred to block 123 where the vector entry detected as 0 in block 122 is set equal to counter CYCL~NT, and counter CNTREM is decremented by 1. The interrogation loop is continued until decision block 1~4 determines that the last entry in count vector CNTREM(N) 35 has been interrogated. As a result of this loop, time stamps equal to the present cycle count are entered into vector CNTREM(N~ for each product unit removedO It should be noted that'if more than one product unit is detected as being removed during a single cycle, several of the entries in count vector CNTREM(N) will have the same value.
Control is then transferred to block 126 where counter Q and N are both reset. In block 127, counter N
is incremented and a loop is begun wherein the individual entries of counter vector CNTREM(N) are interrogated in decision block 128. For each non-zero entry in vector 10 CNTREM(N), counter Q is incremented by 1 in block 129.
The loop is retraced until decision block 131 determines that each element of vector CNTREM(N) has been inter-rogated. As a result of this loop, counter Q indicates the number of non-zero entries in count vector CNTREM(N).
In decision block 132, counter Q is compared with parameter K3 to determine if the periodic unit removal limit has been exceeded. If so, variable ALARM
is set equal to "3" in block 133 and the alarm is sounded in block 134. Control is then transferred to block 118 20 where the flag MOTFLAG2 is updated as are weight readings WTRDG3 and WTRDG2. Control is then transferred back to block 136 (Fig. 4A) where the loop is once again begun.
Referring back to Fig. 4A, in block 136J which operates identically to block 56, the states of switches 25 Sl and S2 are again sensed. This is in order to detect any changes in the states of switches 51 and 52 under action of switch 53 (Eig. 3).
Next decision blocks 137, 139 and 140 are used to detect the positon of key-lock switch 50 (Fig. 3~. If 30 key-lock switch 50 is in the lock-up mode (or if switch 53 has placed key-lock switch 50 in the lock-up mode), block 137 directs control to block 138 where appropriate parameters are minimized in order to place the rack at its highest theft prevention sensitivity. Control is 35 then transferred to block 59 where the entire loop is retraced.
If block 139 does not detect lock-up, control - :: -2~,~
is transferred to block 138 where normal mode is detected. If key lock switch 50 is in the normal mode positon, control is transferred to block 59, and the loop is retraced.
If block 139 decides key lock switch 50 is not in the normal mode, control is transferred to decision block 140 where, if key lock switch 50 is in the restock mode, block 136 is again reentered without retracing the main loop. Otherwise, the rnain loop is retraced by entering block 59.
Referring now to Fig. 5, the alarm routine will be described. In block 141, it is determined if variable ALAR~ is equal to "3" or "4". If not, control is trans-ferred immediately to block 146. If so, counter N is reset in block 142, and a loop comprising blocks 143-145 is traversed a sufficient number of times to reset all entries of vectors CNT~EM(N) and M~TPER(N). Then the alarm is sounded in block 146.
In summary, switches S2-1, S2-2 and S2-3 are positioned by the user of the system as shown in Table VI
to accom~odate the number of weight transducers in the rack in use. Parameter Kl, the instantaneous removal limit, is set by positioning switches Sl-l, Sl-2 and Sl-3 as shown in Table II, and is variable from 1 to 8 product ~5 units.
Switches Sl-4, Sl-5 and Sl-6 are used to set the number of product units which must be removed over a time period to cause an alarm. This is called the perio-dic removal limit, K3, and is adjustable from 3 to 10 product units as shown in Table IV. The time period, K5, for-the periodic removal limit is set by positioning switches S2-4, S2-5 and S2-6, as shown in Table V. In addition, an alarm will sound if the display rack is disturbed continuously for a number of cycles settable by switch Sl-8 (parameter K2) as shown in Table III.
Finally, rack tampering or "swapping" of other ~erch~nd-ise ~or product units contained In the rack is dete~ted ` ' ~
: .
if five unstable episodes (parameter K~) occur within the time period set by parameter K5.
The product rack will acknowledge removal of product units (when not in excess of an alarm limit) by S an adjustable local tone or synthesized voice which can be set to %ero volume. The separately adjustable local alarm tone can also be set to zero volume if local alarm is not desired. The alarm signal can be transmitted to a remote receiver, over wire or radio link, which will sound an alarm at a remote location. The local tones are both adjustable in volume, tone and duration.
A principal factor in determining how restrictive the various programmable alarm criteria for periodic removal should be is the extent to which legiti-mate purchases cause false alarms. This would of courseoccur during peak $raffic hours. The following is a table displaying the results of a computer simulation which was based on the following assumptions:
1. During peak traffic hours, ten customers remove one product unit and five customers remove two product units for total sales of 20 product units during a peak hour.
2. The purchases occur at random times.
3. The predicted false alarm rate is the num-ber of false alarms which would occur during 200 suchpeak hours.
TABLE VII
Predicted False Alarms Per 200 Peak Hours Alarm Limit Time Period K5 Kl 1 2 3 4 5 6 7 8
TABLE VII
Predicted False Alarms Per 200 Peak Hours Alarm Limit Time Period K5 Kl 1 2 3 4 5 6 7 8
4 5 12 1~ 29 ...
:
.: -., " .
' ~
7~6~;
'O O O O 1 2 3 3 It should be noted that odd numbered settings for the product unit alarm limit permit more restrictive settings without significantly higher incidence of false alarms. ~hen time period and alarm limit settings are restricted to the lowest values which do not cause intol-erable false alarm activity, the maximum protection against shoplifting is afforded. While theft of very few product units over an extended period of time may go undetected because this mimics plausible normal activity, the monetary loss of this type of theft is minimal.
While the present invention has been described with reference to a particular preferred embodiment, the invention is not limited to the specific example given, and other embodiments and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.
.. .
~:: - . .. .
.
:
.: -., " .
' ~
7~6~;
'O O O O 1 2 3 3 It should be noted that odd numbered settings for the product unit alarm limit permit more restrictive settings without significantly higher incidence of false alarms. ~hen time period and alarm limit settings are restricted to the lowest values which do not cause intol-erable false alarm activity, the maximum protection against shoplifting is afforded. While theft of very few product units over an extended period of time may go undetected because this mimics plausible normal activity, the monetary loss of this type of theft is minimal.
While the present invention has been described with reference to a particular preferred embodiment, the invention is not limited to the specific example given, and other embodiments and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.
.. .
~:: - . .. .
.
Claims (104)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of indicating unauthorized removal of product units from a product unit rack including the steps of:
monitoring a weight of said rack;
detecting a disturbance of said rack, according to monitored weight;
calculating a number of product units removed from said rack corresponding to a difference in monitored weights before and after said disturbance; and providing an indication of unauthorized removal if said number of product units removed from said rack is greater than a programmable limit.
monitoring a weight of said rack;
detecting a disturbance of said rack, according to monitored weight;
calculating a number of product units removed from said rack corresponding to a difference in monitored weights before and after said disturbance; and providing an indication of unauthorized removal if said number of product units removed from said rack is greater than a programmable limit.
2. A method according to claim 1, wherein said indication is an alarm.
3. A method according to claim 2, wherein said alarm is a local alarm audible in a vicinity of said rack.
4. A method according to claim 2, wherein said alarm is a remote alarm audible at a location remote from said rack.
5. A method according to claim 4 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
6. A method according to claim 4 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
7. A method according to claim 1 further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
8. A method according to claim 1 further comprising the step of:
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
9. A method according to claim 8 further comprising the step of:
selectively activating and deactivating said locking step.
selectively activating and deactivating said locking step.
10. A method according to claim 9, wherein said step of selectively activating and deactivating is controlled manually.
11. A method according to claim 9, wherein said step of selectively activating and deactivating is controlled automatically by a real-time clock.
12. A method of indicating removal of product units from a product unit rack including the steps of:
monitoring the weight of said rack;
detecting changes in said weight;
calculating a number of product units removed from said rack corresponding to each said change;
and providing an indication of removal if a sum of said number of product units is greater than a programmable limit during a programmable time period.
monitoring the weight of said rack;
detecting changes in said weight;
calculating a number of product units removed from said rack corresponding to each said change;
and providing an indication of removal if a sum of said number of product units is greater than a programmable limit during a programmable time period.
13. The method according to claim 12, wherein said indication is an alarm.
14. A method according to claim 13, wherein said alarm is a local alarm audible in a vicinity of said rack.
15. A method according to claim 13, wherein said alarm is a remote alarm audible at a location remote from said rack.
16. A method according to claim 15 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
17. A method according to claim 15 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
18. A method according to claim 12 further comprising the steps of:
locking said rack in a restock mode wherein at said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
19. A method according to claim 12 further comprising the step of:
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
20. A method according to claim 19 further comprising the step of:
selectively activating and deactivating said locking step.
selectively activating and deactivating said locking step.
21. A method according to claim 20, wherein said step of selectively activating and deactivating is controlled manually.
22. A method according to claim 20, wherein said step of selectively activating and deactivating is controlled automatically by a real-time clock.
23. A method of indicating disturbance of a product rack containing product units including the steps of:
monitoring the weight of said rack;
detecting changes in said weight;
determining a number of weight changes which are less in magnitude than a weight change corre-sponding to removal of a product unit;
providing an indication of disturbance if said number is greater than a programmable limit during a programmable time period.
monitoring the weight of said rack;
detecting changes in said weight;
determining a number of weight changes which are less in magnitude than a weight change corre-sponding to removal of a product unit;
providing an indication of disturbance if said number is greater than a programmable limit during a programmable time period.
24. A method according to claim 23, wherein said indication is an alarm.
25. A method according to claim 24, wherein said alarm is a local alarm audible in a vicinity of said rack.
26. A method according to claim 24, wherein said alarm is a remote alarm audible at a location remote from said rack.
27. A method according to claim 26 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
28. A method according to claim 26 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
29. A method according to claim 23 further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed;
and locking in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed;
and locking in a normal mode wherein said step of providing an indication is performed.
30. A method according to claim 23 further comprising the step of:
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
31. A method according to claim 30 further comprising the step of:
selectively activating and deactivating said locking step.
selectively activating and deactivating said locking step.
32. A method according to claim 31, wherein said step of selectively activating and deactivating is controlled manually.
33. A method according to claim 31, wherein said step of selectively activating and deactivating is controlled automatically by a real-time clock.
34. A method of indicating disturbance of a product rack containing product units including the steps of:
consecutively sampling the weight of said rack;
calculating differences between said con-secutive samples;
providing an indication of distrubance if a successive number of differences, greater than a programmable limit, are each greater than a first threshold and less than a second threshold.
consecutively sampling the weight of said rack;
calculating differences between said con-secutive samples;
providing an indication of distrubance if a successive number of differences, greater than a programmable limit, are each greater than a first threshold and less than a second threshold.
35. The method according to claim 34, wherein said indication is an alarm.
36. A method according to claim 35, wherein said alarm is a local alarm audible in a vicinity of said rack.
37. A method according to claim 35, wherein said alarm is a local alarm audible at a location remote from said rack.
38. A method according to claim 37 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
39. A method according to claim 37 further comprising:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
40. A method according to claim 34 further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed;
and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed;
and locking said rack in a normal mode wherein said step of providing an indication is performed.
41. A method according to claim 34 further comprising the step of:
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
locking said rack in a lock-up mode wherein said programmable limit is set to a predetermined minimum.
42. A method according to claim 41 further comprising the step of:
selectively activating and deactivating said locking step.
selectively activating and deactivating said locking step.
43. A method according to claim 42, wherein said step of selectively activating and deactivating is controlled manually.
44. A method according to claim 429 wherein said step of selectively activating and deactivating is controlled automatically by a real-time clock.
45. A method according to claim 34, wherein said second threshold is a weight change corresponding to removal of a product unit.
46. A method of indicating theft of product units from a product unit rack including the steps of:
monitoring the weight of said rack including said product units;
detecting changes in said weight;
calculating a number of product units removed corresponding to each said change;
providing a first indication of theft if said number of product units removed is greater than a first limit;
providing a second indication of theft if, during a first time period, said number of product units removed is greater than a second limit;
providing a third indication of theft if a number of consecutive detected weight changes, not corre-sponding to product unit removal, exceeds a third limit;
and providing a fourth indication of theft if a number of detected weight changes, not corresponding to product unit removal, exceeds a fourth limit during a second time period.
monitoring the weight of said rack including said product units;
detecting changes in said weight;
calculating a number of product units removed corresponding to each said change;
providing a first indication of theft if said number of product units removed is greater than a first limit;
providing a second indication of theft if, during a first time period, said number of product units removed is greater than a second limit;
providing a third indication of theft if a number of consecutive detected weight changes, not corre-sponding to product unit removal, exceeds a third limit;
and providing a fourth indication of theft if a number of detected weight changes, not corresponding to product unit removal, exceeds a fourth limit during a second time period.
47. A method according to claim 46 further comprising the step of:
generating an audible acknowledgement if said number of product units removed is greater than one and less than said first limit.
generating an audible acknowledgement if said number of product units removed is greater than one and less than said first limit.
48. A method according to claim 47, wherein said acknowledgement is a tone.
49. A method according to claim 47, wherein said acknowledgement is a synthesized voice.
50. A method according to claim 46 further comprising the steps of:
sounding at least one alarm in response to said first, second, third or fourth indications of theft.
sounding at least one alarm in response to said first, second, third or fourth indications of theft.
51. A method according to claim 50, wherein at least one of said at least one alarm is a remote alarm audible at a location remote from said rack.
52. A method according to claim 50, wherein at least one of said at least one alarm is a local alarm audible in a vicinity of said rack.
53. A method according to claim 46 further comprising the steps of:
locking said rack in a restock mode wherein said steps of monitoring, detecting and calculating, and said steps of providing said first, second, third and fourth indications are not performed; and locking said rack in a normal mode wherein said steps of monitoring, detecting and calculating, and said steps of providing said first, second, third and fourth indications of theft are performed.
locking said rack in a restock mode wherein said steps of monitoring, detecting and calculating, and said steps of providing said first, second, third and fourth indications are not performed; and locking said rack in a normal mode wherein said steps of monitoring, detecting and calculating, and said steps of providing said first, second, third and fourth indications of theft are performed.
54. A method according to claim 46 further comprising the step of:
locking said rack in a lock-up mode wherein at least one of said first, second, third and fourth limits is set to a predetermined minimum.
locking said rack in a lock-up mode wherein at least one of said first, second, third and fourth limits is set to a predetermined minimum.
55. A method according to claim 54, wherein said locking step is manually controllable by a rack operator.
56. A method according to claim 54, wherein said locking step is automatically controllable according to a time of a real-time clock.
57. An anti-theft product unit rack comprising:
a weight sensor for sensing a weight of said-rack including said product units:
means for detecting changes in said weight;
means for calculating a number of product units removed from said rack for each detected change in weight;
means for indicating theft if said calcu-lated number for a given change is greater than a first limit;
means for calculating a sum of numbers of product units removed for a series of said detected changes in weight;
means for indicating theft if said sum is greater than a second limit during a time period.
a weight sensor for sensing a weight of said-rack including said product units:
means for detecting changes in said weight;
means for calculating a number of product units removed from said rack for each detected change in weight;
means for indicating theft if said calcu-lated number for a given change is greater than a first limit;
means for calculating a sum of numbers of product units removed for a series of said detected changes in weight;
means for indicating theft if said sum is greater than a second limit during a time period.
58 A rack according to claim 57 further comprising:
means for locking said rack in a first mode wherein each of said means for indicating theft is disabled, for locking said rack in a second mode wherein each of said means for indicating theft is enabled, and for locking said rack in a third mode wherein at least one of said first and second limits is set to a predeter-mined minimum.
means for locking said rack in a first mode wherein each of said means for indicating theft is disabled, for locking said rack in a second mode wherein each of said means for indicating theft is enabled, and for locking said rack in a third mode wherein at least one of said first and second limits is set to a predeter-mined minimum.
59. A rack according to claim 58, wherein said means for locking is a key lock switch.
60. A rack according to claim 57 further com-prising:
means for locking said rack in a mode wherein at least one of said first and second limits is set to a predetermined minimum.
means for locking said rack in a mode wherein at least one of said first and second limits is set to a predetermined minimum.
61. A rack according to claim 60, wherein said means for locking is a manual key lock switch.
62. A rack according to claim 58 further comprising:
a real-time clock for selectively activating and deactivating said means for locking according to a time of said clock.
a real-time clock for selectively activating and deactivating said means for locking according to a time of said clock.
63. An anti-theft product unit rack comprising:
means for sensing a weight of said rack including said product units;
means for detecting changes in said weight;
means for calculating respective magnitudes of said detected changes;
means for calculating a number of product units removed from said rack corresponding to each said change according to a respective magnitude;
means for providing an indication of theft if said number of product units for a change exceeds a first limit;
means for providing an indication of theft if a sum of numbers of product units for changes occur-ring during a first time period exceeds a second limit;
and means for providing an indication of theft if a number of weight changes, having a respective magni-tude indicating removal of no product units, exceeds a third limit during a second time period.
means for sensing a weight of said rack including said product units;
means for detecting changes in said weight;
means for calculating respective magnitudes of said detected changes;
means for calculating a number of product units removed from said rack corresponding to each said change according to a respective magnitude;
means for providing an indication of theft if said number of product units for a change exceeds a first limit;
means for providing an indication of theft if a sum of numbers of product units for changes occur-ring during a first time period exceeds a second limit;
and means for providing an indication of theft if a number of weight changes, having a respective magni-tude indicating removal of no product units, exceeds a third limit during a second time period.
64. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means, responsive to said means for measuring, for detecting disturbance of said group of product units;
means, responsive to said means for detecting disturbance, for calculating a number of product units removed from said group according to a difference between a measured weight of said group before a detected disturbance and a measured weight of said group after said detected disturbance; and means for indicating theft if said number of product units removed from said group exceeds a limit.
means for measuring a weight of a group of product units;
means, responsive to said means for measuring, for detecting disturbance of said group of product units;
means, responsive to said means for detecting disturbance, for calculating a number of product units removed from said group according to a difference between a measured weight of said group before a detected disturbance and a measured weight of said group after said detected disturbance; and means for indicating theft if said number of product units removed from said group exceeds a limit.
65. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for calculating a number of product units removed from said group for each said change according to a magnitude of each said change;
means for calculating a sum of said numbers of product units for each said change occurring during a programmable time period; and means for indicating theft if said sum is greater than a programmable limit.
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for calculating a number of product units removed from said group for each said change according to a magnitude of each said change;
means for calculating a sum of said numbers of product units for each said change occurring during a programmable time period; and means for indicating theft if said sum is greater than a programmable limit.
66. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for detecting a number of weight changes having magnitudes less than a predetermined value, said predetermined value corresponding to removal of one product unit from said group;
means for indicating product unit theft if said number is greater than a programmable limit during a programmable time period.
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for detecting a number of weight changes having magnitudes less than a predetermined value, said predetermined value corresponding to removal of one product unit from said group;
means for indicating product unit theft if said number is greater than a programmable limit during a programmable time period.
67. An apparatus for detecting theft of product units from a group of product units comprising:
means for sampling a weight of a group of product units at a substantially constant rate;
means for calculating differences between successive weight samples;
means for indicating theft of product units from said group if a number of said differences between successive weight samples exceeds a programmable limit.
means for sampling a weight of a group of product units at a substantially constant rate;
means for calculating differences between successive weight samples;
means for indicating theft of product units from said group if a number of said differences between successive weight samples exceeds a programmable limit.
68. A method of indicating removal of product units from a product unit rack including the steps of:
monitoring a weight of said rack;
detecting a change in said weight;
calculating a number of product units removed from said rack corresponding to said change in weight;
providing an indication of unauthorized removal if said number of product units is greater than a limit; and generating an acknowledgement of authorized removal if said number of product units removed from said rack is greater than zero and less than or equal to said limit.
monitoring a weight of said rack;
detecting a change in said weight;
calculating a number of product units removed from said rack corresponding to said change in weight;
providing an indication of unauthorized removal if said number of product units is greater than a limit; and generating an acknowledgement of authorized removal if said number of product units removed from said rack is greater than zero and less than or equal to said limit.
69. A method according to claim 68, wherein said indication is an alarm.
70. A method according to claim 69, wherein said alarm is a local alarm audible in a vicinity of said rack.
71. A method according to claim 68, wherein said alarm is a remote alarm audible at a location remote from said rack.
72. A method according to claim 71, further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
73. A method according to claim 71, further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
74. A method according to claim 68, further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
75. A method according to claim 68, wherein said acknowledgement is a tone.
76. A method according to claim 68, wherein said acknowledgement is a synthesized voice.
77. A method of indicating removal of product units from a product unit rack including the steps of:
monitoring the weight of said rack;
detecting changes in said weight;
calculating a number of product units removed from said rack corresponding to each said change; and providing an indication of removal if a sum of said number of product units is greater than a limit during a time period.
monitoring the weight of said rack;
detecting changes in said weight;
calculating a number of product units removed from said rack corresponding to each said change; and providing an indication of removal if a sum of said number of product units is greater than a limit during a time period.
78. The method according to claim 77, wherein said indication is an alarm.
79. A method according to claim 78, wherein said alarm is a local alarm audible in a vicinity of said rack.
80. A method according to claim 78, wherein said alarm is a remote alarm audible at a location remote from said rack.
81. A method according to claim 80 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
82. A method according to claim 80 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
83. A method according to claim 77 further comprising the steps of;
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
84. A method of indicating disturbance of a product rack containing product units including the steps of:
monitoring the weight of said rack;
detecting changes in said weight;
determining a number of weight changes which are less in magnitude than a weight change corresponding to removal of a product unit;
providing an indication of disturbance if said number is greater than a limit during a time period.
monitoring the weight of said rack;
detecting changes in said weight;
determining a number of weight changes which are less in magnitude than a weight change corresponding to removal of a product unit;
providing an indication of disturbance if said number is greater than a limit during a time period.
85. A method according to claim 84, wherein said indication is an alarm.
86. A method according to claim 85, wherein said alarm is a local alarm audible in a vicinity of said rack.
87. A method according to claim 86, wherein said alarm is a remote alarm audible at a location remote from said rack.
88. A method according to claim 87 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
89. A method according to claim 87 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
90. A method according to claim 84 further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
91. A method of indicating disturbance of a product rack containing product units including the steps of:
consecutively sampling the weight of said rack;
calculating differences between said consecutive samples;
providing an indication of disturbance if a successive number of differences, greater than a limit number, are each greater than a first threshold and less than a second threshold.
consecutively sampling the weight of said rack;
calculating differences between said consecutive samples;
providing an indication of disturbance if a successive number of differences, greater than a limit number, are each greater than a first threshold and less than a second threshold.
92. The method according to claim 91, wherein said indication is an alarm.
93. A method according to clam 92, wherein said alarm is a local alarm audible in a vicinity of said rack.
94. A method according to claim 92, wherein said alarm is a remote alarm audible at a location remote from said rack.
95. A method according to claim 94 further comprising the step of:
transmitting said indication to said remote location over a wire.
transmitting said indication to said remote location over a wire.
96. A method according to claim 94 further comprising the step of:
transmitting said indication to said remote location by radio link.
transmitting said indication to said remote location by radio link.
97. A method according to claim 91 further comprising the steps of:
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
locking said rack in a restock mode wherein at least said step of providing an indication is bypassed; and locking said rack in a normal mode wherein said step of providing an indication is performed.
98. A method according to claim 91, wherein said second threshold is a weight change corresponding to removal of a product unit.
99. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means for detecting a change in said weight;
means for calculating a number of product units removed from said group according to a magnitude of said change; and means for indicating theft if said number of product units removed exceeds a limit; and means for acknowledging legitimate removal if said number of product units removed is greater than zero and less than or equal to said limit.
means for measuring a weight of a group of product units;
means for detecting a change in said weight;
means for calculating a number of product units removed from said group according to a magnitude of said change; and means for indicating theft if said number of product units removed exceeds a limit; and means for acknowledging legitimate removal if said number of product units removed is greater than zero and less than or equal to said limit.
100. A rack according to claim 99 further comprising:
means for locking said rack in a first mode wherein said means for indicating theft is disabled, and for locking said rack in a second mode wherein said means for indicating theft is enabled.
means for locking said rack in a first mode wherein said means for indicating theft is disabled, and for locking said rack in a second mode wherein said means for indicating theft is enabled.
101. A rack according to claim 100, wherein said means for locking is a key lock switch.
102. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for calculating a number of product units removed from said group for each said change according to a magnitude of each said change;
means for calculating a sum of said numbers of product units for each said change occurring during a time period; and means for indicating theft if said sum is greater than a limit.
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for calculating a number of product units removed from said group for each said change according to a magnitude of each said change;
means for calculating a sum of said numbers of product units for each said change occurring during a time period; and means for indicating theft if said sum is greater than a limit.
103. An anti-theft apparatus for use in a product unit rack, or the like, including:
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for detecting a number of weight changes having magnitudes less than a predetermined value, said predetermined value corresponding to removal of one product unit from said group;
means for indicating product unit theft if said number is greater than a limit during a time period.
means for measuring a weight of a group of product units;
means for detecting changes in said weight;
means for detecting a number of weight changes having magnitudes less than a predetermined value, said predetermined value corresponding to removal of one product unit from said group;
means for indicating product unit theft if said number is greater than a limit during a time period.
104. An apparatus for detecting theft of product units from a group of product units comprising:
means for sampling a weight of a group of product units at a substantially constant rate;
means for calculating differences between successive weight samples;
means for indicating theft of product units from said group if a number of said differences between successive weight samples exceeds a limit.
means for sampling a weight of a group of product units at a substantially constant rate;
means for calculating differences between successive weight samples;
means for indicating theft of product units from said group if a number of said differences between successive weight samples exceeds a limit.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US87415986A | 1986-06-13 | 1986-06-13 | |
| US874,159 | 1986-06-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1272266A true CA1272266A (en) | 1990-07-31 |
Family
ID=25363109
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000539541A Expired - Lifetime CA1272266A (en) | 1986-06-13 | 1987-06-12 | Anti-theft product rack and method |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP0249501B1 (en) |
| JP (1) | JPS6324491A (en) |
| KR (1) | KR880000056A (en) |
| AT (1) | ATE61678T1 (en) |
| AU (1) | AU596189B2 (en) |
| BR (1) | BR8703016A (en) |
| CA (1) | CA1272266A (en) |
| DE (1) | DE3768558D1 (en) |
| ES (1) | ES2021041B3 (en) |
| ZA (1) | ZA874217B (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5000274A (en) * | 1989-01-19 | 1991-03-19 | K-Tron International, Inc. | Weight sensor |
| GB8925452D0 (en) * | 1989-11-10 | 1989-12-28 | Transalarm Ltd | A load security system |
| JP2010097457A (en) * | 2008-10-17 | 2010-04-30 | Okamura Corp | Article display apparatus |
| JP2010094332A (en) * | 2008-10-17 | 2010-04-30 | Okamura Corp | Merchandise display apparatus |
| JP2010097456A (en) * | 2008-10-17 | 2010-04-30 | Okamura Corp | Article display apparatus |
| JP2010097458A (en) * | 2008-10-17 | 2010-04-30 | Okamura Corp | Commodity display |
| JP5444792B2 (en) * | 2009-03-31 | 2014-03-19 | 大日本印刷株式会社 | Burglar alarm system and method |
| GB2483096A (en) * | 2010-08-27 | 2012-02-29 | Tag Company Uk Ltd | System for detecting theft and/or unauthorised removal of items from storage shelves |
| KR101363101B1 (en) * | 2012-06-13 | 2014-02-13 | 이정윤 | Display table |
| JP2019064646A (en) * | 2017-09-29 | 2019-04-25 | 日立オートモティブシステムズメジャメント株式会社 | Liquid supply system |
| CN110147723B (en) * | 2019-04-11 | 2022-08-19 | 苏宁云计算有限公司 | Method and system for processing abnormal behaviors of customers in unmanned store |
| JP7424764B2 (en) * | 2019-06-28 | 2024-01-30 | 株式会社野村総合研究所 | theft deterrent device |
| DE102019121704A1 (en) * | 2019-08-12 | 2021-02-18 | ADECK Systems GmbH | METHOD, EVALUATION DEVICE, DISPLAY DEVICE, DISPLAY DEVICE, COMPUTER PROGRAM PRODUCT AND STORAGE MEDIUM FOR AUTOMATED DETECTION OF SHOP THEFT |
| GB202103826D0 (en) * | 2021-03-19 | 2021-05-05 | Swing Fitness Ltd | Exercise apparatus |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1267630A (en) * | 1969-05-16 | 1972-03-22 | Fmc Corp | Automatic marketing system |
| US4108363A (en) * | 1975-06-25 | 1978-08-22 | Iida Susumu | Record controlled mechanical store |
| JPS5832430B2 (en) * | 1979-05-07 | 1983-07-13 | シャープ株式会社 | electronic cash register |
| US4512428A (en) * | 1983-05-05 | 1985-04-23 | K-Tron International, Inc. | Weighing apparatus and method |
| JPH0719907B2 (en) * | 1985-07-03 | 1995-03-06 | 株式会社日立製作所 | Method of manufacturing thin film semiconductor device |
-
1987
- 1987-06-11 ZA ZA874217A patent/ZA874217B/en unknown
- 1987-06-12 CA CA000539541A patent/CA1272266A/en not_active Expired - Lifetime
- 1987-06-12 AU AU74184/87A patent/AU596189B2/en not_active Ceased
- 1987-06-12 DE DE8787305259T patent/DE3768558D1/en not_active Expired - Lifetime
- 1987-06-12 AT AT87305259T patent/ATE61678T1/en active
- 1987-06-12 BR BR8703016A patent/BR8703016A/en not_active Application Discontinuation
- 1987-06-12 ES ES87305259T patent/ES2021041B3/en not_active Expired - Lifetime
- 1987-06-12 EP EP19870305259 patent/EP0249501B1/en not_active Expired - Lifetime
- 1987-06-13 JP JP62147801A patent/JPS6324491A/en active Pending
- 1987-06-13 KR KR1019870006004A patent/KR880000056A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| ZA874217B (en) | 1988-03-30 |
| EP0249501A3 (en) | 1988-10-05 |
| KR880000056A (en) | 1988-03-23 |
| AU7418487A (en) | 1987-12-17 |
| AU596189B2 (en) | 1990-04-26 |
| EP0249501A2 (en) | 1987-12-16 |
| ATE61678T1 (en) | 1991-03-15 |
| BR8703016A (en) | 1988-03-08 |
| EP0249501B1 (en) | 1991-03-13 |
| DE3768558D1 (en) | 1991-04-18 |
| ES2021041B3 (en) | 1991-10-16 |
| JPS6324491A (en) | 1988-02-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |