Abstract:
Systems and methods for harvesting mechanical energy in a security tag. The methods involve: applying by a tool a pushing force so as to cause a securement mechanism disposed within the security tag to deform; transferring mechanical energy to a spring sleeve when the securement mechanism deforms due to loading applied by the tool; using an energy harvester (e.g., a piezo element or a magnet/solenoid element) to harness the mechanical energy applied by the tool, where the energy harvester is at least partially coupled to the securement mechanism; and converting the mechanical energy to electrical energy. The energy harvester is disposed between the securement mechanism and an Electronic Article Surveillance (“EAS”) or Radio Frequency IDentification (“RFID”) component of the security tag.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of U.S. Provisional Patent Application No. 62/204,094 filed on Aug. 12, 2015. The contents of this Provisional Patent Application are hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This document relates generally to hard tags. More particularly, this document relates to hard tag locking clamps with an energy harvesting element. 
       BACKGROUND 
       [0003]    Hard tags are typically passive devices that contain some element that responds to an external power source when operated properly. The hard tags are incapable of communicating information indicating that they have been detached or unlocked to an external device. 
       SUMMARY 
       [0004]    The present disclosure concerns implementing systems and methods for harvesting mechanical energy in a security tag. The methods comprise: applying by a tool a pushing force so as to cause a securement mechanism disposed within the security tag to deform; transferring mechanical energy to a spring sleeve when the securement mechanism deforms due to loading applied by the tool; using an energy harvester (e.g., a piezo element, a magnet/solenoid element and/or a Micro-Electro-Mechanical-Systems (“MEMS”) device) to harness the mechanical energy applied by the tool; and converting the mechanical energy to electrical energy. The energy harvester is at least partially coupled to the securement mechanism. The energy harvester may be disposed between the securement mechanism and an Electronic Article Surveillance (“EAS”) or Radio Frequency IDentification (“RFID”) component of the security tag. 
         [0005]    In some scenarios, the energy harvester comprises a piezo element attached to the spring sleeve of the securement mechanism. The energy harvester detects distortion of the spring sleeve when the securement mechanism is engaged by the tool. Positive and negative leads are attached to the energy harvester. The energy harvester transmits an electrical signal to an electronic component of the security tag (e.g., an EAS component and/or an RFID component). 
         [0006]    In some scenarios, the energy harvester comprises a coil and a permanent magnet that is coupled to the securement mechanism. The permanent magnet moves past the coil so as to induce an electrical charge when the securement mechanism rotates as a result of the pushing force being applied thereto. The electrical charge is transferred to an electronic component of the security tag as to indicate that the securement mechanism has been engaged by the tool. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0007]    The present disclosure will be described with reference to the following drawing figures, in which like numerals represent like items throughout the figures. 
           [0008]      FIG. 1  is a perspective view of an exemplary security tag and detachment mechanism that is useful for understanding the present solution. 
           [0009]      FIG. 2  is a cross sectional side view of the exemplary security tag shown in  FIG. 1  that is useful for understanding the present solution. 
           [0010]      FIG. 3  is an illustration of an exemplary security tag in a locked position. 
           [0011]      FIG. 4  is an illustration of an exemplary security tag in an unlocked position. 
           [0012]      FIG. 5  is a perspective view of a securement mechanism of the security tag shown in  FIG. 1 . 
           [0013]      FIG. 6  is an illustration of a securement mechanism having an energy harvester coupled thereto. 
           [0014]      FIG. 7  is an illustration of showing the energy harvester of  FIG. 6  coupled to positive and negative electrical leads. 
           [0015]      FIG. 8  is an illustration of another exemplary security tag having an energy harvester for harnessing the applied mechanical energy. 
           [0016]      FIG. 9  is an illustration of another exemplary security tag having an energy harvester for harnessing the applied mechanical energy. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    It will be readily understood that the components of the present solution as generally described herein and illustrated in the appended figures could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various implementations of the present solution, as represented in the figures, is not intended to limit the scope of the present disclosure, but is merely representative of various implementations. While the various aspects of the present solution are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. 
         [0018]    The present solution may be embodied in other specific forms without departing from its spirit or essential characteristics. The described solution is to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by this detailed description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. 
         [0019]    Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussions of the features and advantages, and similar language, throughout the specification may, but do not necessarily, refer to the same embodiment. 
         [0020]    Furthermore, the described features, advantages and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the invention can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. 
         [0021]    Reference throughout this specification to “one embodiment”, “an embodiment”, or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the present invention. Thus, the phrases “in one embodiment”, “in an embodiment”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. 
         [0022]    As used in this document, the singular form “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. As used in this document, the term “comprising” means “including, but not limited to”. 
         [0023]    The present disclosure concerns a hard tag. The hard tag comprises an electro-mechanical element incorporated with a locking mechanism. The locking mechanism facilitates the attachment and detachment of the hard tag to an article (e.g., a piece of clothing). The electro-mechanical element provides an electrical response in the event of the hard tag&#39;s detachment from the article. In this regard, the electro-mechanical element deforms (i.e., bends) when engaged. The deformation causes the generation of a signal. The signal is sent from the hard tag to an external device. At the external device, the signal is processed so as to provide feedback to a user or data acquisition system indicating that the hard tag has been detached from the article. 
         [0024]    Many times a thief or perpetrator will attempt to unlock the hard tag in an authorized manner, defeating the security and purpose of the hard tag. If the thief or perpetrator is successful, (s)he will detach the hard tag from the article, hide the hard tag within a facility, and leave the facility with the article. Consequently, the retailer unknowingly loses this article of inventory. Knowledge of such theft is obtained when the hidden hard tag is later discovered by an employee. By adding a smart element to the hard tag, the hard tag is able to record or notify an external system in the event of a detachment thereof from an article. As such, retailers are able to detect when a thief is maliciously attempting to defeat a hard tag. 
         [0025]    Referring now to  FIGS. 1-5 , there is provided schematic illustrations useful for understanding an exemplary security tag  100 . As shown in  FIGS. 1-5 , the security tag  100  includes a housing  104  with an upper housing member  106  joined to a lower housing member  108 . The housing members  106 ,  108  can be joined together via an adhesive, a mechanical coupling means (e.g., snaps, screws, etc.), or a weld (e.g., an ultrasonic weld). The housing  104  can be made from a rigid or semi-rigid material, such as plastic. The housing  104  has an opening  204  formed therein such that at least a portion of a tack assembly  110  (or attachment element) can be inserted into the security tag for facilitating the attachment of the security tag to an article  114  (e.g., a piece of clothing). EAS and/or RFID components  306  are contained within the housing  104 . EAS and RFID components of security tags are well known in the art, and therefore will not be described herein. 
         [0026]    Tack assembly  110  has a tack head  112  and an elongate tack body  202  extending down and away from the tack head. The tack body  202  is sized and shaped for insertion into opening  204  and removal from opening  204 . A plurality of grooves (not shown in  FIGS. 1-5 ) may be formed along a length of the tack body  202  for engagement with a securement mechanism  206  disposed within the housing  104 . When the grooves are engaged by the securement mechanism  206 , the security tag  100  is secured to the article  114 . Thereafter, unauthorized removal of the article  114  from a controlled area can be detected by a monitoring device of an EAS system. Such monitoring devices are well known in the art, and therefore will not be described herein. Still, it should be understood that at least one sensor (not shown in  FIGS. 1-5 ) is disposed within the housing  104 . The sensor includes, but is not limited to, an acoustically resonant magnetic sensor. In all cases, the sensor generates signals which can be detected by the monitoring device. 
         [0027]    Such detection occurs when the security tag is present within a surveillance zone established by the monitoring device. The surveillance zone is usually established at an access point for the controlled area (e.g., adjacent to a retail store entrance and/or exit). If the article  114  enters the surveillance zone with the security tag  100 , then an alarm may be triggered to indicate possible unauthorized removal thereof from the controlled area. In contrast, if the article  114  is authorized for removal from the controlled area, then the security tag  100  thereof can be deactivated and/or detached therefrom using a detachment mechanism  102  (or external tool). Consequently, the article  114  can be carried through the surveillance zone without being detected by the monitoring system and/or without triggering the alarm. 
         [0028]    The detachment mechanism  102  is sized and shaped to at least be partially slidingly inserted into and removed from an insert space  116  formed in the housing  104 . When inserted into insert space  116 , the detachment mechanism  102  travels through an arcuate channel  302  so as to be guided towards the securement mechanism  206 . In this regard, the detachment mechanism  102  has a generally arcuate shape matching that of the arcuate channel  302 . Upon engagement with the securement mechanism  206 , the detachment mechanism  102  releases the tack body  202  therefrom. Next, the tack body  202  can be removed from the housing, so as to decouple the security tag  100  from the article  114 . 
         [0029]    A schematic illustration of the securement mechanism  206  is provided in  FIG. 5 . As noted above, the securement mechanism  206  is specifically adapted to accommodate release of the tack body  202  via the detachment mechanism  102  (or arcuate probe) moving in the arcuate channel  302 . The securement mechanism  206  is generally in the form of a spring clamp securely disposed within the housing  104  of the security tag so as to be pivotable (or rotatable) about an axis  208 . In this regard, the spring clamp comprises a clamp body  502  and jaws  504 ,  506 . The clamp body  502  includes a mounting part  508  extending laterally of jaw  506  and a release part  510  extending laterally of jaw  504 . The mounting part  508  includes a mounting aperture  512  facilitating the pivotable movement of the securement mechanism  206  within the housing of the security tag. The pivotable movement allows the securement mechanism  206  to be transitioned by the detachment mechanism  102  (or arcuate probe) from a first position in which the tack assembly is locked thereto (as shown in  FIG. 3 ) and a second position in which the tack assembly is released or unlocked therefrom (as shown in  FIG. 4 ). 
         [0030]    Each of the jaws  504 ,  506  extends outwardly of the plane of the clamp body  502  and then inwardly toward the other jaw. The jaws  504 ,  506  terminate in facing edges  514 ,  516 . These edges extend from a common edge  518  of the clamp body  502  inwardly toward each other, then curve outwardly away from each other to define an aperture  520  (typically, circular or elliptical) for receiving the tack body  202 . The edges  514 ,  516  then continue in aligned fashion and end in an elongated, lateral slot  522  in the clamp body  502 . The lateral slot lies inward of a further clamp body edge  524  which opposes the clamp body edge  518 . 
         [0031]    A further laterally extending elongated spring sleeve  526  is attached by a joint area  528  to the side  530  of the edge  524  bordering the mounting part  508 . The sleeve  526  extends along the length of the edge  524  and is also out of the plane of the clamp body  502 . 
         [0032]    For mounting and supporting the spring clamp  502 , the lower housing member  108  of the security tag  100  includes a circular mount  402 . The spring clamp  302  is mounted, via aperture  312  of the mounting part  308 , on the circular mount  402 . In this way, the mounting part  508  can be rotated about the circular mount  402 . The spring clamp  502  is thus able to pivot about the mounting part  508 . 
         [0033]    When an end of the tack assembly  110  is introduced in the downward direction through the opening  204  in the upper housing member  106 , the tack body  204  is directed to aperture  520  of the securement mechanism  206 . This causes the jaws  504 ,  506  to spread open and allow the tack body  204  to pass there through. 
         [0034]    When the downward movement of the tack assembly  110  is stopped, the jaws  504 ,  506  retract and clutch the tack body  204 . In this position, the jaws  504 ,  506  prevent upward movement of the tack assembly  110 . As such, the security tag  100  becomes securely coupled to the article  114 . 
         [0035]    In order to release the tack body  204  from the jaws  504 - 306 , the detachment mechanism  102  is introduced into the insert space  116  formed in the housing  104  of the security tag  100 . Rotation of the detachment mechanism  102  causes it to be moved in and guided by the arcuate channel  302  until the end  118  abuts portion  532  of the securement mechanism  206 . Continued rotational movement of the detachment mechanism  102  causes force to be applied to portion  532  of the securement mechanism  206 . This force, in turn, causes the clamp body  502  to rotate about the support area  508 . The jaw  504  is thus enabled to spread away from jaw  506  due to the force of the tack body  204 , which is being held stationary by jaw  506 . As a result, aperture  520  expands, releasing the tack body  204  from the clutch of the jaws. The tack assembly  110  can now be moved in the upward direction past the jaws, via an upward force on the tack head  112 . 
         [0036]    During rotation of the clamp body  502 , the spring sleeve  526  at the joint area  528  is compressed. After the tack assembly  110  is separated from the housing  104 , the detachment mechanism  102  is rotated in the reverse direction. This reverse rotation disengages the detachment mechanism  102  from the securement mechanism  206 . Consequently, the spring sleeve  526  rotates in an opposite direction so as to be brought back to its original position. Thereafter, the detachment mechanism  102  is guided out of the arcuate channel  302  and is removed from insert space  116  formed in the housing  104 . 
         [0037]    As evident from the above discussion, the detachment mechanism  102  is provided to deflect the securement mechanism  206  so as to allow the tack assembly  110  to be removed from the housing  104 . The detachment mechanism  102  may be part of an external detacher. Detachers are well known in the art, and therefore will not be described herein. When the tack assembly  110  is removed from the housing  104 , the security tag  100  can be decoupled from an article  114  (e.g., a piece of clothing). 
         [0038]    The deflection of the securement mechanism  206  results from an application of mechanical energy by the detachment mechanism  102 . The present invention provides a means for harnessing the applied mechanical energy. The means includes an additional element disposed between the securement mechanism and EAS/RFID component(s). The additional element can include, but is not limited to, a piezo (or piezoelectric) element, a magnet/solenoid element, and/or a MEMS device. 
         [0039]    Referring now to  FIG. 6 , there is provided a schematic illustration of a securement mechanism  600 . The securement mechanism  600  is similar to or the same as securement mechanism  206  of  FIG. 5 . As such, the discussion provided above in relation to securement mechanism  206  is sufficient for understanding securement mechanism  600 . Unlike securement mechanism  206 , securement mechanism has an energy harvester  602  coupled thereto for harnessing the applied mechanical energy. 
         [0040]    The energy harvester  602  includes, but is not limited to, a piezo or piezoelectric element that is able to generate an electric charge in response to applied mechanical stress. The energy harvester  602  is attached to the spring sleeve  604  of the securement mechanism  600 . When the securement mechanism  600  deforms due to loading applied by a detachment mechanism (e.g., detachment mechanism  102  of  FIG. 1 ), mechanical energy is transferred to the spring sleeve  604 . As such, the energy harvester  602  detects distortion of the spring sleeve  604  when the securement mechanism  600  is engaged by the detachment mechanism. The mechanical energy provided by the detected distortion of the spring sleeve  604  can be converted to electrical energy. The spring sleeve&#39;s distortion is shown in  FIGS. 4 and 8 . This distortion comprises a bending of at least a portion of the spring sleeve. In other scenarios, the spring sleeve may remain perfectly elastic. In both cases, the behavior of the spring sleeve is analyzed for generating an electrical signal. The spring sleeve may be configured for a one time use event or a multiple use event. 
         [0041]    In this regard, positive and negative leads  702 ,  704  can be attached to the energy harvester  602  as shown in  FIG. 7 . When the leads  702 ,  704  are attached to the energy harvester  602 , the energy harvester  602  can transmit an electrical signal to another object, such as a microprocessor of the EAS/RFID component(s)  802  shown by arrows  804  and  806  of  FIG. 8 . The leads  702 ,  704  are electrically coupled to the EAS/RFID component(s)  802  via wires and/or traces disposed on or in a circuit board  804 . The wires and/or traces are not visible in  FIG. 8 . 
         [0042]    When the electrical signal is applied to the EAS/RFID component(s)  802 , it generates and transmits a notification signal to an external device (e.g., an EAS pedestal, RFID reader and/or a user or data acquisition system). This notification provides an indication that the hard tag has been detached from the article. The notification may also comprise information specifying an area or zone within a facility where the hard tag resides after being detached from the article. In effect, a user (e.g., retail personnel) is able to make a quick and informed decision as to whether a potential theft is taking place. 
         [0043]    In some scenarios, a MEMS device  706  is provided in addition to the piezo element. The MEMS device  706  may be coupled to the spring sleeve  604  as shown in  FIG. 7  or disposed on a circuit board  804 . In both cases, the MEMS device  706  is connected in series between the energy harvester  602  and the EAS/RFID component(s)  802 . The MEMS device  706  is generally configured to process the electrical signal generated by the piezo element for increasing or converting power so as to increase the efficiency of electric power transfer. 
         [0044]    The present solution is not limited to the particulars of  FIGS. 6-8 . Means other than the piezo element may be employed for harnessing the applied mechanical energy. For example, the piezo element  602  may be replaced with a MEMS device. In this case, the MEMS device would detect deformation of the spring sleeve and generate an electrical signal in response to the detected deformation. The electrical signal would be provided from the MEMS device to the EAS/RFID component(s)  802 . 
         [0045]    MEMS devices are well known in the art, and therefore will not be described herein. Any known or to be known MEMS sensor can be used here without limitation provided that it can: (a) process the electrical signal generated by the piezo element for increasing or converting power so as to increase the efficiency of electric power transfer; or (b) detect deformation of the spring sleeve and generate an electrical signal in response to the detected deformation. 
         [0046]    Referring now to  FIG. 9 , there is provided an illustration of another exemplary security tag  900  having an energy harvester  902  for harnessing the applied mechanical energy. The energy harvester  902  comprises a coil  904  and a permanent magnet  906 . The permanent magnet  906  is coupled to the securement mechanism  908 . When the securement mechanism  908  rotates, the permanent magnet  906  moves past the coil  904 , thereby inducing a small electrical charge. The electrical charge can then be transferred to the EAS/RFID component(s) (not shown in  FIG. 9  for clarity of the energy harvester&#39;s illustration) so as to indicate that the securement mechanism  908  has been engaged by a detachment mechanism  910  or other detachment tool. 
         [0047]    When the electrical charge is transferred to the EAS/RFID component(s), it generates and transmits a notification signal to an external device (e.g., an EAS pedestal, RFID reader and/or a user or data acquisition system). This notification provides an indication that the security tag  900  has been detached from the article. The notification may also comprise information specifying an area or zone within a facility where the security tag  900  resides after being detached from the article. In effect, a user (e.g., retail personnel) is able to make a quick and informed decision as to whether a potential theft is taking place. 
         [0048]    In some scenarios, the security tag  900  also comprises a MEMS device (not shown in  FIG. 9  for clarity of the energy harvester&#39;s illustration) for improving the efficiency of electrical charge. The MEMS device is disposed on a circuit board (not shown in  FIG. 9  for clarity of energy harvester&#39;s illustration) so as to be connected in series between the energy harvester  902  and the EAS/RFID component(s). The MEMS device is generally configured to process the electrical signal generated by the energy harvester  902  for increasing or converting power so as to increase the efficiency of electric power transfer. 
         [0049]    The present solution is not limited to the particulars of  FIG. 9 . For example, a MEMS device may replace the coil  904 . In this case, the MEMS device generates an electrical signal when the spring sleeve deforms (i.e., bends) and transfers the electrical signal to the EAS/RFID component(s). 
         [0050]    MEMS devices are well known in the art, and therefore will not be described herein. Any known or to be known MEMS sensor can be used here without limitation provided that it can: (a) process the electrical signal generated by the energy harvester for increasing or converting power so as to increase the efficiency of electric power transfer; or (b) generates an electrical signal when the spring sleeve deforms (i.e., bends) and transfers the electrical signal to another device. 
         [0051]    Notably, the present invention is not limited to the particulars of the above-described exemplary architectures. For example, the security tag may comprise an active tag having an internal power source. In this case, a sensor may be coupled to an internal housing sidewall at a position suitable for monitoring and detecting movement of a securement mechanism by an external tool. The sensor can include, but is not limited to, a light sensor or a through beam sensor. The securement mechanism can include, but is not limited to, a clamping mechanism or a magnetic post/spring mechanism. The external tool can include, but is not limited to, a magnet or a probe. Accordingly, the present invention covers a plurality of different mechanical, electrical and electro-mechanical mechanisms that can detect movement of a securement mechanism and provide notification of such movement to a remote computing system. 
         [0052]    All of the apparatus, methods, and algorithms disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the invention has been described in terms of preferred embodiments, it will be apparent to those having ordinary skill in the art that variations may be applied to the apparatus, methods and sequence of steps of the method without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain components may be added to, combined with, or substituted for the components described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those having ordinary skill in the art are deemed to be within the spirit, scope and concept of the invention as defined. 
         [0053]    The features and functions disclosed above, as well as alternatives, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements may be made by those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments.