Abstract:
An embodiment is an EAS tag that may be included in an EAS system. More specifically, an embodiment is a reusable EAS tag including an arcuate channel with an L-shaped keyway, into which an appropriate corresponding tool, in the form of an arcuate probe, can be inserted for releasing a clamp and thereby detaching the EAS tag from its article. Prevents tampering and activation of the detaching mechanism with other tools than the intended one.

Description:
BACKGROUND 
       [0001]    Electronic article surveillance (EAS) systems are well known in the art and are used for inventory control and to prevent theft and similar unauthorized removal of articles from a controlled area. Typically, in such systems a system transmitter and a system receiver are used to establish a surveillance zone that must be traversed by any articles being removed from the controlled area. 
         [0002]    An EAS tag is affixed to each article and includes a marker or sensor adapted to interact with a signal being transmitted by the system transmitter into the surveillance zone. This interaction causes a further signal to be established in the surveillance zone which further signal is received by the system receiver. Accordingly, upon movement of a tagged article through the surveillance zone, a signal will be received by the system receiver, identifying the unauthorized presence of the tagged article in the zone. An alarm may thereafter be triggered by the system receiver, on the EAS tag, or both, to further expose the unauthorized presence of the tagged article in the surveillance zone. 
         [0003]    Certain types of EAS tags have been designed to be reusable and accordingly include releasable attachment devices for affixing the tags to the articles. Such attachment devices are further designed to be releasable by authorized personnel only so that unauthorized removal of a tag from its article is avoided. To this end, many attachment devices are made releasable only through the use of an associated special tool or detaching mechanism. Clever thieves, however, have developed methods to defeat some EAS tags. 
       SUMMARY 
       [0004]    An embodiment is an electronic article surveillance (EAS) tag that forms part of an EAS system. In general, the EAS tag may include a sensor, transmitter, or the like to emit a detectable signal when it is located within a monitored surveillance zone. The EAS tag may be attached to anything, and may for example be attached to an article of clothing. A detaching device may remove an EAS tag when surveillance is not necessary (e.g., after the item has been purchased). While the EAS tag is attached to, for example, an article of clothing, a monitoring system may monitor the surveillance zone for the EAS tag signal to ensure that the article of clothing including the EAS tag is not removed from the surveillance zone without triggering an alarm or the like. 
         [0005]    The EAS tag includes a tag body and a tack that detachably engages with the tag body via a pin. More specifically, the tag body includes a rotary clamp that detachably engages the pin to secure the tack to the tag body. The rotary clamp may be disengaged from the pin by accessing and actuating the rotary clamp through an arcuate channel formed in the tag body. The shape of the arcuate channel increases the difficulty of accessing the rotary clamp with anything other than a tool or probe specifically designed for such a purpose. Such a tool or probe, among other features, would share the radius of the arcuate channel. 
         [0006]    The arcuate channel of an embodiment may further include a keyway though which the tool or probe must travel to access the rotary clamp and in turn disengage the rotary clamp from the tack pin. The keyway of an embodiment, based on the depth of the arcuate channel at which it is located and its opening relative to the arcuate channel coupled with the arcuate channel&#39;s features preceding and following the keyway, may individually and in combination further increase the difficulty of accessing the rotary clamp with anything other than the tool or probe specifically designed for such a purpose as noted above. Accordingly, the keyway and the features of the arcuate channel adjacent to the keyway cooperatively combat improvised methods for accessing the rotary clamp and subsequently deter unauthorized defeat of the EAS system thereby. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The subject matter regarded as embodiments is particularly pointed out an distinctly claimed in the following portion of the specification. The embodiments, both as to organization an method of operation, may be best understood by reference to the following detailed description when read with the accompanying drawings in which: 
           [0008]      FIG. 1  illustrates an EAS tag of an embodiment. 
           [0009]      FIG. 2  illustrates an SEC hook and rotator block assembly of an embodiment. 
           [0010]      FIG. 3  illustrates a cutaway view of the EAS tag of an embodiment including the SEC hook and rotary clamp. 
           [0011]      FIG. 4  illustrates the detail of an SEC hook. 
           [0012]      FIG. 5  illustrates a formed fish tape. 
           [0013]      FIG. 6  illustrates an EAS tag of an embodiment. 
           [0014]      FIG. 7  illustrates a cross section of an EAS tag of an embodiment. 
           [0015]      FIG. 8  illustrates a cutaway view of the upper housing of an EAS tag of an embodiment. 
           [0016]      FIG. 9  illustrates a cutaway view of the lower housing of an EAS tag of an embodiment. 
           [0017]      FIG. 10  illustrates a cutaway view of the upper housing of an EAS tag of an embodiment including a formed fish tape. 
           [0018]      FIG. 11  illustrates a cutaway view of the upper housing of an EAS tag of an embodiment including a formed fish tape. 
           [0019]      FIG. 12  illustrates a cutaway view of the upper housing of an EAS tag of an embodiment including an SEC hook and a rotary clamp. 
           [0020]      FIG. 13  illustrates an EAS system including an EAS tag of an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Embodiments of an electronic article security tag will be described. Reference will now be made in detail to a description of these embodiments as illustrated in the drawings. While the embodiments will be described in connection with these drawings, there is no intent to limit them to drawings disclosed herein. On the contrary, the intent is to cover all alternatives, modifications, and equivalents within the spirit and scope of the described embodiments as defined by the accompanying claims. 
         [0022]    One embodiment may comprise an EAS tag that may be included in an EAS system. More specifically, an embodiment is an EAS tag including an arcuate channel and additional features to hinder the removal of the EAS tag with devices other than those specifically designed for such a purpose. The EAS system may further include a detaching device and a monitoring system. In general, the EAS tag may include a sensor, transmitter, or the like to emit a detectable signal when it is located within a monitored surveillance zone. The EAS tag may be attached to anything, and may for example be attached to an article of clothing. The detaching device may remove an EAS tag when surveillance is not necessary (e.g., after the item has been purchased). While the EAS tag is attached to, for example, an article of clothing, the monitoring system may monitor the surveillance zone for the EAS tag signal to ensure that the article of clothing including the EAS tag is not removed from the zone without triggering an alarm or the like. 
         [0023]      FIG. 1  illustrates EAS tag  100  including body  110 , tack  120  including pin  130 , and arcuate channel  130  within body  110 . The EAS tag may be attached to any item, for example an article of clothing, by piercing the item or article of clothing with the pin  130  of tack  120  and detachably securing the pin  130  of tack  120  to the body  110 . In an embodiment, the pin  130  is detachably secured to body  110  in such a manner that it requires a specially designed tool to detach the EAS tag  100  from the, for example, article of clothing. In the absence of such a tool, the EAS tag is difficult to remove. As noted, the body  110  of an embodiment may include a sensor, transmitter, or the like to emit a detectable signal when it is located within a monitored surveillance zone. Accordingly, the difficulty of removing the EAS tag  100  without the tool may deter the removal of the, for example, article of clothing including the EAS tag  100  from the monitored surveillance zone. 
         [0024]      FIG. 2  illustrates an SEC hook and rotator block assembly combination  200 . In an embodiment, The SEC hook  220  is a curved steel bar that is 0.094″ by 0.094″ in cross section and has a Rockwell “C” hardness approximately between 54 and 58. The length of the SEC hook  220  is about ⅓ of the circumference of a circle with a 1″ radius (i.e., approximately 2 inches). With respect to its attachment to the rotator block assembly  210 , the SEC hook  220  includes a distal tip end  230 . The tip end  230  cross section is in the shape of a backward “L.” The L-shape may extend toward the rotator block assembly  210  approximately 0.60 inch from the distal end of the SEC hook  220 . In an embodiment, depending on the location of the L-shaped keyway in the arcuate channel  130 , the “L” of the tip end  230  may extend further or less than 0.06 inch as will be explained more fully below. The thickness of each leg on the backwards “L” is approximately 0.028 inch. The other end of the SEC hook  220  is mounted on a rotator block assembly  210  that rotates the SEC hook  220  about an axis of rotation at the center of the 1″ radius circle congruent with the 1″ radius circle for which SEC hook  220  spans an arc. 
         [0025]      FIG. 3  illustrates a cutaway view of the EAS tag  100  including the SEC hook  220 . In operation, the SEC hook  220  rotates along the axis of rotation of the rotator block assembly  210  (rotator block assembly not illustrated) such that the tip end  230  of the SEC hook  220  navigates the arcuate channel  130 . The SEC hook  220  may be rotated into an L-shaped key way in the arcuate channel  130  of the EAS tag  100  approximately 1 inch where the tip end  230  of the SEC hook  220  may engage and rotate a rotary clamp  310  about rotary clamp pivot point  320  approximately less than 5 degrees to unlock and release the pin  130  of the tack  120 . The tack  120  can thereafter be removed from the EAS tag  100  housing, freeing the garment or other item to which it was attached. The rotary clamp  310  may be biased to the “lock” position, so when the released tack  120  is removed from the EAS tag  100 , the rotary clamp  310  is ready to accept and detachably lock onto or grip another inserted tack  120 . 
         [0026]      FIG. 4  illustrates the detail of SEC hook  220 . Tip end  230  of SEC hook  220  further includes vertical leg  400  an horizontal leg  410 . As noted, the SEC hook  220  may be rotated into the arcuate channel  130  of the EAS tag  100  approximately 1 inch where the tip end  230  of the SEC hook  220  may engage and rotate a rotary clamp  310 . In an embodiment, as will be described more fully below, the tip end  230  of the SEC hook  220  may further navigate an L-shaped keyway within the arcuate channel  130 . The overall cross section of the tip end  230  is approximately 0.094 inches by 0.094 inches. Both the vertical leg  400  and the horizontal  410  leg may have a thickness of approximately 0.028 inches. In an embodiment, the vertical leg  400 , horizontal leg  410 , or both may have a chamfer, fillet, or the like at one or more of their edges to facilitate the insertion of the SEC hook  220  including tip end  230  in the arcuate channel  130  and/or to facilitate the tip end  230  engagement with the rotary clamp  310 . 
         [0027]      FIG. 5  illustrates a formed fish tape  500  including tip end  510  that may be able to actuate the rotary clamp  310  and release pin  130  of tack  120  in lieu of SEC hook  220 . Someone interested in bypassing an EAS system may use such a formed fish tape  500  to remove the EAS tag  100 . For example, a thin rigid wire formed into a semicircle (cross section approximately 0.032 inches by 0.096 inches common to automobile windshield wiper blade inserts or electrical fish tape) may be forcibly inserted into the L-shaped key way inside the arcuate channel  130  until it engages the rotary clamp  310  and releases the pin  130  of tack  120 . For an experienced operator, such an EAS system defeat may be performed in under ten seconds, thereby compromising the security features of the EAS system. 
         [0028]      FIG. 6  illustrates EAS tag  600  including several features to mitigate the use of a formed fish tape  500  to defeat the EAS system. In addition to the like-numbered features of EAS tag  100 , EAS tag  600  may further include spring gate  610 , catch  620 , and abutment  630 . The abutment  630  may be a substantially planar rigid member with a vertical and horizontal opening forming a substantially L-shaped opening to receive the corresponding L-shape of the tip end  230  of the SEC hook  220 . The rigid member of abutment  630  may be positioned substantially perpendicularly in the arcuate channel  130 . The vertical opening of abutment  630  may be sized and positioned to allow the vertical leg  400  of the tip end  230  to closely pass through when the SEC hook  220  is inserted into the arcuate channel  130  to actuate, for example the rotary clamp  310  to release the pin  130  of tack  120 . 
         [0029]    The abutment  630  mechanism may further include a spring gate  610  assembly for preventing insertion of the formed fish tape  500 . The spring gate  610  assembly may further include a catch  620  to catch the formed fish tape  500  and prevent further insertion of the formed fish tape  500  into the arcuate channel  130 . The catch  620  may disposed on one end of the spring gate  610 . The spring gate  610  may be attached to the EAS tag  600  body (i.e., lower housing  640 ) and biased so that the catch  620  may be against a wall of the arcuate channel  130  and in front of the vertical opening in the rigid member of abutment  630 . In operation, the horizontal leg  410  of the SEC hook  220  may push against the bias of the spring gate  610  upon insertion of the SEC hook  220  in the arcuate channel  130  wherein the catch  620  is pushed away from the vertical opening in the rigid member of abutment  630  allowing the SEC hook  220  to closely pass therethrough. In an embodiment, the catch  620  may be a bent portion of the end of the spring gate  610 . 
         [0030]      FIGS. 7 through 12  illustrate EAS tag  700  of an embodiment to further hinder the use of, for example, formed fish tape  500  to defeat the EAS system. For example,  FIG. 7  illustrates a cross section of EAS tag  700  including SEC hook  220  in the arcuate channel  130 . In an embodiment, at least a portion of the arcuate channel may have an L-shaped cross section similar to the tip end  230  of the SEC hook  220 . In an embodiment, as illustrated by  FIG. 8 , the arcuate channel  130  may include an L-shaped keyway  800 . The EAS tag of an embodiment may include, for example an upper housing  720  and a lower housing  710  that may be adjoined. Various features of the arcuate channel  130  and L-shaped keyway  800  will be described in turn that both individually and in combination increase the difficulty of removing tack  120  without SEC hook  220 . 
         [0031]    For example, the channel horizontal leg  740  or channel vertical leg  750  or both may be altered at various points to combat, for example, formed fish tape  500 . More specifically, as noted the formed fish tape  500  may have a cross section approximately 0.032 inches by 0.096 inches whereas each leg of the tip end  230  of SEC hook  220  (e.g., vertical leg  400  and horizontal leg  410 ) each is approximately 0.028 inches by 0.094 inches. Accordingly, either the channel horizontal leg  740 , the channel vertical leg  750 , or both may be fabricated to accept, for example, the 0.028 inch thick vertical leg  400  or horizontal leg  410  but may substantially reject the 0.032 inch thick formed fish tape  500  by narrowing the channel legs accordingly. For example, the horizontal leg and the vertical leg each may have a width of approximately between 0.028 and 0.032 inches and a height relative to their intersection of approximately between 0.094 and 0.096 inches to accommodate the tip end  230  of the SEC hook  220 . The dimensions of an embodiment may also serve to better steer an intruding formed fish tape  500  (if forced into the arcuate channel  130  or of a different dimension than formed fish tape  500 ) into additional obstacles by providing less leeway for the formed fish tape  500  to circumnavigate the obstacles. In an embodiment, the channel horizontal leg  740  and the channel vertical leg  750  dimensions described above are formed by L-shaped keyway  800  (through which, for example,  FIG. 7  illustrates a cross section) 
         [0032]    Further, the channel vertical leg, including channel vertical leg wall  750  may be altered. For example, if the channel horizontal leg  740  is constricted as noted above to accommodate the tip end  230  of SEC hook  220  and substantially reject the formed fish tape  500 , the channel vertical leg  730  may be enlarged. In an embodiment, the channel vertical leg  730  vertical depth may be increased beyond that which would be required to accommodate the 0.094 inch vertical leg  400  of the SEC hook  220 . In an embodiment, the deeper vertical leg  730  may better guide the formed fish tape  500 . In an embodiment, the deeper channel vertical leg  730  may preferentially guide the formed fish tape  500  so that the formed fish tape  500 , when inserted in the arcuate channel  130 , prefers the channel vertical leg  730  over the channel horizontal leg  740 . In this fashion, in an embodiment a “road block” or other obstacle may be included in or adjacent to the channel vertical leg  730  that may impede or obstruct the advancement of the formed fish tape  500  to engage the rotary clamp  310  to release the pin  130  of tack  120 . In an embodiment, the channel horizontal leg  740  and the channel vertical leg  750  dimensions described above are formed by L-shaped keyway  800  (through which, for example,  FIG. 7  illustrates a cross section). 
         [0033]    As illustrated by  FIG. 8 , in an embodiment for which a portion of the arcuate channel  130  has an L-shaped cross section, the L-shaped cross section may be formed by L-shaped keyway  800 . Versus the entire arcuate channel  130  having an L-shaped cross-section, the L-shaped keyway of an embodiment may make it more difficult for a formed fish tape  500  to traverse the arcuate channel  130  and engage the rotary clamp  310  to release the pin  130  of tack  120 . 
         [0034]    For example, unless substantially formed in the same arc as the arcuate channel  130  (i.e., a 1.0 inch radius), without the entire L-shaped length of the arcuate channel  130  to guide it, the formed fish tape  500  may encounter the face of the L-shaped keyway  800  as an obstacle that would substantially prevent the further insertion of the formed fish tape  500  to engage the rotary clamp  310 . Further, following the L-shaped keyway  800 , the arcuate channel  130  may further open or widen, for example with a deeper channel vertical leg wall  750  or widened channel end  810 . By each feature or combination of the features, a formed fish tape  500  that is inserted in the arcuate channel  130  and further advanced through the L-shaped keyway  800  may nevertheless, without additional guiding surfaces or walls following the L-shaped keyway  800 , not have enough strength on its own to engage the rotary clamp  310  to release the pin  130  of tack  120 . 
         [0035]      FIG. 9  illustrates the lower housing  710  of the EAS tag  700  of an embodiment including the channel horizontal leg  740 . In an embodiment, the channel horizontal leg  740  forms part of the L-shaped keyway  800 . The channel horizontal leg  740  may be a guiding surface, for example, for formed fish tape  500 . More specifically, if the formed fish tape  500  is inserted into the channel vertical leg  730 , it will slide along the surface of the channel horizontal leg  740  as a guide. The channel horizontal leg  740  can thereby steer the inserted formed fish tape into roadblocks or obstacles as will be explained with reference to  FIG. 10  and  FIG. 11 . 
         [0036]    As noted, without guiding surfaces or walls, the formed fish tape may not have enough strength on its own to engage the rotary clamp  310  to release the pin  130  of tack  120 . For example, and as illustrated by  FIG. 11 , to increase the strength of the formed fish tape  500 , a kink bend  1010  may be formed in the fish tape as illustrated by formed fish tape  1000 . The formed fish tape  1000  including kink bend  1010  may be advanced through the L-shaped keyway  800 , but upon exiting the L-shaped keyway  800 , the kink bend  1010  may steer the formed fish tape  1000  to a roadblock or obstacle created by the channel vertical leg wall  750 . Accordingly, while the kink bend  1010  may be required to increase the strength of the formed fish tape  1000 , it may nevertheless, given the channel vertical leg wall  750  roadblock, substantially prevent the formed fish tape  1000  from reaching the rotary clamp  310 . 
         [0037]    Conversely, and as explained with reference to the widening of the arcuate channel  130  at channel end  810  after the L-shaped keyway, if the formed fish tape has a smooth bend (e.g., formed fish tape  500 ), following the traversal of the L-shaped keyway  800 , the widening of the arcuate channel across from the rotary clamp  310 , coupled with the absence of a strength increasing kink bend  1010 , encourages the formed fish tape  500  to flex away from the rotary clamp  310  as illustrated by flex  1100 . As noted above, the formed fish tape  500  without additional guiding surfaces or walls between the L-shaped keyway  800  and the rotary clamp  310  may not have enough strength on its own to engage the rotary clamp  310  to release the pin  130  of tack  120 . 
         [0038]      FIG. 12  illustrates the EAS tag  700  of an embodiment including, for example, the L-shaped keyway  800 . Unlike formed fish tape  500  or formed fish tape  1000  including kink bend  1010 , the SEC hook  220  may navigate the arcuate channel  130 , and in particular the L-shaped keyway  800  and the various roadblocks and obstacles formed thereby, to contact and engage the rotary clamp  310  to release the pin  130  of tack  120 . 
         [0039]    It is to be understood that while illustrated (e.g., by  FIG. 7 ) an described substantially in the same cross section, in an embodiment the legs of the L-shaped keyway  800  (e.g., horizontal leg  740  and vertical leg  730 ) may be alternatively positioned. For example, one leg of the L-shaped keyway  800  may be positioned at a different location along the arcuate channel  130  than the other leg of the L-shaped keyway  800 . For example, the formed fish tape  500  may experience, as it is inserted into and traverses the arcuate channel  130 , one leg of the L-shaped keyway at a different depth than the other leg. The separation or combination of the horizontal leg  740  and vertical leg  730  of the L-shaped keyway  800  may further allow the L-shaped keyway  800  to be more precisely configured to hinder or substantially interrupt the intrusion of L-shaped keyway  800 . 
         [0040]      FIG. 13  illustrates an EAS system including the EAS tag  700  of an embodiment.  FIG. 13  shows an EAS system  1300  used to detect or sense the EAS tag  700  of an embodiment, for example attached to article  1310 , when passing through a surveillance zone  1320 . An interrogation signal is transmitted into the zone  1320  via a transmitting device  1330 . A signal resulting from interaction of a sensor in the EAS tag with the transmitted signal is received at a receiver  1340  that communicates with a detection and alarm device  1350 . The latter detects the received signal and generates an alarm indicating the presence of the EAS tag  600  and the article  1310  in the surveillance zone  1320 . 
         [0041]    While certain features of the embodiments have been illustrated as described herein, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the embodiments.