Smart sensor line alarm system

Abstract

Embodiments of the present invention are directed to systems and methods for monitoring a status of a plurality of a merchandise display devices for displaying items of merchandise at respective display positions. For example, the method includes monitoring for a change in a preselected characteristic of a circuit defined by an electrical connection between the security devices and a plurality of nodes and between the nodes and an alarm unit. The method also includes determining whether an item of merchandise has been added to or removed from a respective display position based on a change in the preselected characteristic.

Claims

1. A merchandise security system comprising: a plurality of security devices each configured to be attached to a respective item of merchandise, each of the plurality of security devices configured to be arranged on a display surface at a respective display position in a retail store; an alarm unit electrically connected to each of the plurality of security devices in a circuit, wherein the alarm unit is configured to be enabled for monitoring a change in the preselected characteristic of the circuit defined by the electrical connection between the plurality of security devices and the alarm unit and to be disabled whereby monitoring of the circuit discontinues, wherein the alarm unit is configured to detect a change in the preselected characteristic of the circuit while enabled in response to a security device being added to the circuit, wherein the alarm unit is further configured to detect a change in the preselected characteristic of the circuit while enabled in response to any one of the plurality of security devices being removed from the circuit, and wherein the alarm unit is configured to activate an alarm while enabled in response to detecting a change in the preselected characteristic of the circuit indicative of unauthorized removal of any one of the items of merchandise.

2. The merchandise security system of claim 1, wherein the preselected characteristic is a total resistance of the circuit.

3. The merchandise security system of claim 2, wherein the alarm unit is configured to determine an initial tare value of the total resistance of the circuit and to detect changes in the initial tare value of the total resistance of the circuit when a security device is added to or removed from the circuit.

4. The merchandise security system of claim 3, wherein the alarm unit is configured to determine a new tare value of the total resistance of the circuit in response to a security device being added to the circuit.

5. The merchandise security system of claim 1, further comprising a power supply electrically connected to each of the security devices with a respective power line.

6. The merchandise security system of claim 5, wherein each power line comprises a transformer configured to provide power requirements for a corresponding item of merchandise.

7. A method for monitoring a status of a plurality of security devices for displaying items of merchandise at respective display positions in a retail store, the method comprising: enabling an alarm unit for monitoring a change in a preselected characteristic of a circuit defined by an electrical connection between the plurality of security devices and the alarm unit, the alarm unit configured to be disabled whereby monitoring of the circuit discontinues; monitoring, with the alarm unit while the alarm unit is enabled, for a change in the preselected characteristic of the circuit; detecting, with the alarm unit while the alarm unit is enabled, a change in the preselected characteristic of the circuit in response to a security device being added to the circuit; detecting, with the alarm unit while the alarm unit is enabled, a change in the preselected characteristic of the circuit in response to any one of the plurality of security devices being removed from the circuit; and activating, with the alarm unit while the alarm unit is enabled, an alarm in response to detecting a change in the preselected characteristic of the circuit indicative of unauthorized removal of any one of the items of merchandise.

8. The method of claim 7, wherein the monitoring comprises monitoring a change in a total resistance of the circuit.

9. The method of claim 8, further comprising: determining an initial tare value of the total resistance of the circuit; and detecting changes in the initial tare value when a security device is added to or removed from a respective display position.

10. The method of claim 9, wherein detecting a positive change in the initial tare value is indicative of a security device being added to a display position.

11. The method of claim 10, further comprising determining a new tare value of the total resistance of the circuit when a positive change in the initial tare value is detected.

12. The method of claim 9, wherein detecting a negative change in the initial tare value is indicative of any one of the plurality of security devices being removed from the circuit.

13. The method of claim 12, further comprising activating an alarm when a negative change in the initial tare value is detected.

14. The method of claim 9, further comprising disabling monitoring for a predetermined period of time in response to interaction with a security key.

15. The method of claim 14, further comprising ignoring a change in the initial tare value during the predetermined period of time.

16. The method of claim 14, further comprising establishing a new tare value after the predetermined period of time.

17. A merchandise security system comprising: a plurality of security devices each configured to be attached to a respective item of merchandise, each of the plurality of security devices configured to be arranged on a display surface at a respective display position in a retail store; an alarm unit electrically connected to each of the plurality of security devices in a circuit, wherein the alarm unit is configured to monitor a change in the preselected characteristic of a circuit defined by the electrical connection between the security devices and the alarm unit, wherein the alarm unit is configured to detect a change in the preselected characteristic of the circuit in response to a security device being added to the circuit, and wherein the alarm unit is further configured to detect a change in the preselected characteristic of the circuit in response to any one of the plurality of security devices being removed from the circuit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates a merchandise security line alarm system comprising three (3) Display Positions configured in accordance with embodiments of the invention. As will be described in greater detail hereinafter, additional Display Positions comprising the same or different security devices for displaying additional items of merchandise may be added to the line alarm system in a “daisy chain” manner.

(2) FIG. 2 shows a merchandise security line alarm system including a display counter with a plurality of items of merchandise displayed thereon according to one embodiment of the invention.

DETAILED DESCRIPTION

(3) Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which various embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, and prime notation and multiple prime notations are used to indicate similar elements in alternative embodiments.

(4) Embodiments of the present invention are directed to a line alarm system for display merchandise in which a plurality of Display Positions are linked together in a series arrangement and additional Display Positions may be added by “daisy chaining” another Display Position to the system. The line alarm system may be anchored by (i.e., initiated by or terminated with) an alarm unit operable for monitoring the status of a merchandise display security sensor mounted at each Display Position and for activating an alarm in the event that the security sensor indicates a breach (unsecured) condition.

(5) According to one embodiment, the present invention is a line alarm system 10 for monitoring a plurality of security devices 12 attached to an item or merchandise “M” and positioned on a Display Counter “DC” at a corresponding plurality of Display Positions 40 (see FIG. 2). As shown in FIG. 1, the line alarm system according to one embodiment, indicated generally by reference character 10, comprises an Alarm Unit 20 electrically connected in series to a plurality of Nodes 30 by a common Bus Line 35. In turn, each Node 30 is electrically connected in series to a security device 12 at a corresponding Display Position 40 via a corresponding Sensor Line 45. Likewise, each Node 30 is electrically connected in series to a common power supply (i.e. Power Strip) 50 via a corresponding Power Line 55. If desired, the Alarm Unit may also be electrically connected in series to an optional auxiliary component, such as a Digital Media System 60 for providing advertising content to, and/or for obtaining customer interaction data from, one or more of the Display Positions 40. As shown in FIG. 1, the alarm unit may anchor an electrical circuit defined by the connections between the nodes and the security devices and the connections between the nodes and the alarm unit. As shown, the electrical circuit may terminate at the alarm unit.

(6) The line alarm system 10 overcomes the disadvantages and deficiencies of prior art line alarm systems by utilizing a novel and unique sensing methodology. Instead of detecting a simple “open” in the circuit of the system, the sensing methodology of the present invention monitors a change in a preselected characteristic of the circuit. In an exemplary embodiment, monitoring electronics disposed within the Alarm Unit 20 monitors a change in the overall (total) resistance of the circuit. However, the monitoring electronics of the Alarm Unit 20 may be configured to monitor a change in any characteristic of the circuit, for example a change in the light intensity of an optical circuit of the system. When a Display Position is connected or disconnected, the total resistance of the circuit of the system changes. Based on the direction of the change in the resistance of the circuit, the monitoring electronics can determine whether an item of merchandise was added at a Display Position, or was removed from a Display Position.

(7) In one embodiment, the monitoring electronics of the Alarm Unit 20 determines an initial value of the total resistance as a “tare” value of the system to be monitored. The monitoring electronics then monitors the total resistance of the system for a change in that initial value. If an item of merchandise is added to an existing Display Position (or a new Display Position is created), the total resistance of the system will change in known manner, for example in a positive direction. Accordingly if the monitoring electronics detects a change in the total resistance in a positive direction, the Alarm Unit 20 merely reestablishes the initial value of the total resistance of the system to a new “tare” value. However, if the monitoring electronics detects a change in the total resistance in a negative direction, the Alarm Unit 20 determines that an item of merchandise has been removed from the line alarm system and activates an alarm indicating a potential theft of the item of merchandise.

(8) A particular advantage of a line alarm system 10 according to the invention is that an additional Display Position 40 for another item of merchandise can be incorporated into the system “on the fly” without requiring the system to be turned off. Since the monitoring electronics of the Alarm Unit 20 remain enabled (turned on), the likelihood that store personnel will turn the system off and then accidently or intentionally fail to reactivate (turn on) the system is reduced. In the event that store personnel need to remove a security device from the system 10, or to perform maintenance on the security device or the node at a specific Display Position 40, a security key can be used to cause the monitoring electronics to enter a “sleep” or “maintenance mode.” The monitoring electronics of the Alarm Unit 20 would then discontinue monitoring the total resistance of the system for a limited time (e.g. a maintenance window), or alternatively, would ignore the next negative change in the total resistance of the system and not activate the alarm. Once the predetermined time period elapsed, or the next negative change in the total resistance occurred, the monitoring electronics of the Alarm Unit 20 would reestablish a new “tare” value at the current value of the total resistance of the system and the system would rearmed automatically. In the event that an item of merchandise had been removed to allow a customer to examine and operate the merchandise free of the sensor cable (tether), the monitoring electronics will detect a positive change in the total resistance of the system when the item of merchandise is reattached to the security device and will automatically tare again to the new value of the total resistance of the line alarm system.

(9) Another advantage of a line alarm system 10 according to embodiments of the invention is that different types of security devices can be used at different Display Positions 40 of the line alarm system for protecting various items of merchandise having different operating power (i.e. voltage and/or current) requirements without the need to utilize complex and highly sophisticated monitoring electronics since the monitoring electronics monitors only the total resistance of the line alarm system instead of having to monitor the sense loops of several different security devices operating with different electrical characteristics.

(10) Yet another advantage of a line alarm system 10 according to embodiments of the invention is that the routing and management of the Sensor Lines 45 and Power Lines 55 for the security devices at the various Display Positions 40 is greatly simplified and significantly more aesthetic than prior art line alarm systems for displaying and protecting a like number of items of merchandise.

(11) Yet another advantage of a line alarm system 10 according to embodiments of the invention is that the Power Line 55 for the security device at each of the various Display Positions 40 can comprise a customized transformer 56 configured to provide the appropriate power requirements (i.e. voltage and/or current) for operating the corresponding item of merchandise. Alternatively, the Node 30 at each of the various Display Positions 40 can comprise a customized voltage regulator circuit configured to provide the appropriate operating power to the corresponding item of merchandise.

(12) Many modifications and other embodiments of the invention will be readily apparent to one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is understood and appreciated that the invention is not to be limited to the specific embodiments disclosed herein, and that modifications to the disclosed embodiments and other undisclosed embodiments are intended to be included within the scope of the appended claims.