Abstract:
The invention relates to an RFID label applicator ( 100 ) may include a peeler member ( 140 ) having a peel end ( 142 ), the peeler member being configured to cause an RFID label ( 102 ) to peel away from a web ( 110 ) when the web passes around the peel end; and a label tamp assembly ( 150 ) having a receiving surface ( 612 ) configured to receive the RFID label and to move it into contact with an item ( 104 ) on which the RFID label is to be applied, the label tamp assembly having at least one forward opening in a portion of the receiving surface away from the peeler member and a plurality of rearward openings in a portion of the receiving surface proximate the peeler member, wherein at least one of the forward or rearward openings is configured to draw in air such that a leading portion of the RFID label is substantially secured.

Description:
TECHNICAL FIELD  
       [0001]     The present application relates to radio frequency identification (RFID) label applicators, and more particularly, to a RFID label applicator capable of programming RFID labels, detecting defective RFID labels and rejecting the defective RFID labels.  
       BACKGROUND INFORMATION  
       [0002]     Radio frequency identification (RFID) systems are generally known and may be used for a number of applications such as managing inventory, electronic access control, security systems, automatic identification of cars on toll roads, and electronic article surveillance (EAS). RFID devices may be used to track or monitor the location and/or status of articles or items to which the RFID devices are applied. A RFID system typically comprises a RFID reader and a RFID device such as a tag or label. The RFID reader may transmit a radio-frequency carrier signal to the RFID device. The RFID device may respond to the carrier signal with a data signal encoded with information stored on the RFID device. RFID devices may store information such as a unique identifier or Electronic Product Code (EPC) associated with the article or item.  
         [0003]     RFID devices may be programmed (e.g., with the appropriate EPC) and applied to the article or item that is being tracked or monitored. A RFID reader/programmer may be used to program RFID devices and to detect defective RFID devices. Label applicators have been used to apply programmed RFID labels to items or articles.  
         [0004]     Existing RFID applicators, however, have encountered problems in handling defective labels. In existing RFID applicators, a RFID reader/programmer may be located upstream from the applicator. One problem occurs when tracking a defective label from the point at which it is detected to the point at which it can be rejected. Because of potential differences in the RFID label footprints and web paths through the applicator, the number of labels between the point of detection and the point of rejection may be inconsistent. As a result of this inconsistency, an applicator may reject a good label and may apply a defective label to the product.  
         [0005]     Another problem is that the rejection of defective RFID labels may interrupt the label application process and may result in labels not being applied to items or products. When a defective label is detected using conventional techniques, it may be removed from the process and another label may be re-encoded in its place. Each defective label that is encountered may cut the product application rate by up to an additional 50%. Product lines may need to be run slower so as not to miss a product in the event a defective label is detected.  
       SUMMARY OF THE INVENTION  
       [0006]     The invention relates to an RFID label applicator. Embodiments of the invention may include a peeler member having a peel end, the peeler member being configured to cause an RFID label to peel away from a web when the web passes around the peel end; and a label tamp assembly having a receiving surface configured to receive the RFID label and to move it into contact with an item on which the RFID label is to be applied, the label tamp assembly having at least one forward opening in a portion of the receiving surface away from the peeler member and a plurality of rearward openings in a portion of the receiving surface proximate the peeler member, wherein at least one of the forward or rearward openings is configured to draw in air such that a leading portion of the RFID label is substantially secured. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     The subject matter regarded as the embodiments is particularly pointed out and distinctly claimed in the concluding portion of the specification. The embodiments, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying drawings in which:  
         [0008]      FIG. 1  is a diagrammatic view of a RFID applicator, consistent with one embodiment of the invention.  
         [0009]      FIG. 2  is a side cross-sectional view of one embodiment of a RFID label that can be used in the RFID applicator, consistent with one embodiment of the invention.  
         [0010]      FIG. 3  is a side view of one embodiment of a RFID applicator peeler member with an integrated RFID programming antenna.  
         [0011]      FIGS. 4A-4C  are side views of one embodiment of a label reject assembly in various positions with respect to a RFID applicator peeler member for use in a RFID applicator.  
         [0012]      FIGS. 5A and 5B  are side views of another embodiment of a label reject assembly integrated into a RFID applicator peeler member for use in a RFID applicator.  
         [0013]      FIG. 6A  is a side view of one embodiment of a label tamp assembly.  
         [0014]      FIG. 6B  is a top view of the label tamp assembly shown in  FIG. 6A .  
         [0015]      FIG. 7A  is a bottom view of one embodiment of a vacuum tamp pad that may be used in a label tamp assembly.  
         [0016]      FIG. 7B  is a cross-section view of the vacuum tamp pad shown in  FIG. 7A  taken along line A-A.  
         [0017]      FIG. 7C  is a side view of the vacuum tamp pad shown in  FIG. 7A .  
         [0018]      FIG. 8A  is a side view of another embodiment of a vacuum tamp pad for use in a RFID applicator.  
         [0019]      FIG. 8B  is a bottom view of the vacuum tamp pad shown in  FIG. 8A . 
     
    
     DETAILED DESCRIPTION  
       [0020]     Numerous specific details may be set forth herein to provide a thorough understanding of the embodiments of the disclosure. It will be understood by those skilled in the art, however, that various embodiments of the disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the various embodiments of the disclosure. It can be appreciated that the specific structural and functional details disclosed herein are representative and do not necessarily limit the scope of the disclosure.  
         [0021]     It is worthy to note that any reference in the specification to “one embodiment” or “an embodiment” according to the present disclosure means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.  
         [0022]     Referring to  FIG. 1 , radio frequency identification (RFID) label applicator  100 , consistent with embodiments of the invention, may be used to apply RFID labels  102  to articles or items  104 . The RFID label applicator  100  may also be used to program RFID labels  102 , to detect defective RFID labels, and to reject the defective labels such that the defective labels are not applied to the items  104 . The articles or items  104  may be products, merchandise, or any other items or articles that may be monitored using RFID techniques.  
         [0023]     The RFID labels  102  may be removably secured to a backing material or web  110  such that the RFID labels  102  are supported on the web  110  during programming and may be removed (e.g., peeled away from the web  110 ) for application. The web  110  supporting the labels  102  may be rolled onto a roll  112 , which is unwound to allow the web  110  to pass through the label applicator  100 . After the RFID labels  102  are removed or rejected, scrap web  110   a  may be rewound onto a rewind roll  114 .  
         [0024]     One embodiment of the RFID label applicator  100  may include a web feeding mechanism  120  to feed the web  110 , a RFID programming system  130  to program the RFID labels  102 , a peeler member  140  to peel the RFID labels  102  from the web  110 , a label tamp assembly  150  to apply the RFID labels  102  to the items  104 , and a label reject assembly  160  to reject RFID labels. The RFID label applicator  100  may also include an applicator controller  170  to control operation of the RFID label applicator  100 . The articles or items  104  may be arranged in a line (e.g., a product line) and may be moved, for example, using a conveyor  180  or other similar mechanism. Components in the applicator  100  may be mounted or secured to an applicator frame  108 .  
         [0025]     The RFID label applicator  100  may also include other components not shown in  FIG. 1 . Examples of additional components include, but are not limited to, a label sensor to sense and position the labels  102  relative to the RFID programming system  130 , an item sensor to sense and position the items  104  relative to the tamp assembly  150 , and an integrated printer to print indicia on the labels  102 . One example of a label sensor includes a thru-beam that shines a light from beneath the web to a light sensor  110  positioned above the web  110 .  
         [0026]     The web feeding mechanism  120  may include a tensioning roller  122  and an idler roller  124 , which guide the web  110  with the RFID labels  102  to the peeler member  140 . The web feeding mechanism  120  may also include a drive and nip roller assembly  126  that takes up the scrap web  110   a  and feeds the scrap web  110   a  to the web rewind roll  114 . The drive and nip roller assembly  126  may be driven to pull the scrap web  110   a , thereby causing the web  110  with the RFID labels  102  to pass around the peeler member  140 . The unwind roll  112  and/or rewind roll  114  may also be driven (e.g., with servomotors) to facilitate unwinding of the web  110  and/or rewinding the scrap web  110   a.    
         [0027]     The RFID programming system  130  may include a RFID reader/programmer coupled to one or more RFID programming antennas, as will be described in greater detail below. The RFID programming system  130  may include any RFID reader/programmer known to those skilled in the art for reading and/or programming RFID devices, such as the type known as the Sensormatic® SensorID™ Agile 2 Reader available from Tyco Fire and Security. The RFID programming system  130  may also be capable of detecting defective RFID labels, for example, by attempting to read a RFID label after applying programming signals.  
         [0028]     The peeler member  140  may include a peel tip  142  having a radius and forming an angle such that a RFID label  102  peels away from the web  110  as the web  110  passes around the peel tip  142 . In one embodiment, the radius of the peel tip  142  may be in a range of about 0.030 in. and the angle formed by the peel tip  142  may be in a range of about 90° or less. Other radii and angles are within the scope of the invention and may depend upon the adhesion properties (e.g., the adhesion strength) of the RFID labels  102  on the web  110 . The peeler member  140  may be made of a rigid material such as aluminum. In one embodiment, the peeler member  140  may be in the form of a plate or a bar, although those skilled in the art will recognize other shapes and configurations.  
         [0029]     The label tamp assembly  150  may include a tamp pad  152  coupled to a tamp driving mechanism  154 . The tamp pad  152  contacts the non-adhering side of a RFID label  102   a  that has been removed from the web  110  and holds the RFID label  102   a . The tamp driving mechanism  154  drives the tamp pad  152  and the RFID label  102   a  toward the item  104  to which the RFID label  102   a  is to be applied. One embodiment of the tamp assembly  150  uses a vacuum pressure to retain the RFID label  102   a  in contact with the tamp pad  152 . The vacuum pressure may be released and/or air may be blown from the tamp pad  152  to facilitate application of the RFID label  102   a . Although one embodiment of a label tamp assembly  150  is described herein, the label tamp assembly  150  may include any structure or mechanism for moving a label into contact with an item  104 .  
         [0030]     The label reject assembly  160  may include an accumulation pad  162  coupled to a label reject driving mechanism  164 . Upon determining that a RFID label  102  is to be rejected, the reject driving mechanism  164  drives the accumulation pad  162  into the path of the tamp pad  152 . The tamp pad  152  then applies the rejected RFID label to the accumulation pad  162  instead of the item  104 . A RFID label may be rejected when the label is determined to be defective or for other reasons. Although one embodiment of the label reject assembly  160  is described herein, the label reject assembly  160  may include any structure for intercepting or otherwise preventing a RFID label from being applied to an item  104 .  
         [0031]     The tamp driving mechanism  154  and the label reject driving mechanism  164  may include pneumatic actuated air cylinders, such as the type available from PHD, Inc. When air cylinders are used as the driving mechanisms, the RFID label applicator  100  may also include one or more air pressure gauges  168  to monitor and/or adjust operation of the air cylinders, as is known to those skilled in the art. Although the described embodiment uses air cylinders and rods, those skilled in the art will recognize that other linear actuators or driving mechanisms may be used.  
         [0032]     The applicator controller  170  may be a programmable logic controller (PLC), such as the type available from Allen-Bradley, Omron or Mitsubishi, or a general purpose computer, such as a PC, programmed to control one or more operations of the applicator  100 . The controller  170  may be coupled to the web feeding mechanism  120  (e.g., to the motors, sensors, etc.) to control the feeding of the web  110  around the peeler member  140  and/or to control the positioning of the RFID labels  102  relative to the RFID programming system  130 . The controller  170  may also be coupled to the tamp assembly  150  to control application (or tamping) of programmed and removed RFID labels to the items  104 . The controller  170  may also be coupled to the label reject assembly  160  to control the rejection of labels, for example, when the label is determined to be defective. The controller  170  may also be coupled to a user interface/control panel  172  to enable a user to monitor the application process and/or to provide commands and/or operating parameters to the controller  170 .  
         [0033]     The controller  170  and/or user interface  172  may also be coupled to the RFID programming system  130  to control the RFID programming operations. RFID programming operations may be controlled, for example, by allocating Electronic Product Codes (EPC&#39;s) and/or other data to be sent to the RFID labels  102  upon receiving an indication that the RFID labels  102  are properly positioned relative to the RFID programming system  130 . The controller  170  may also monitor the detection of defective labels to control the label reject assembly  160 . The controller  170  may further collect programming data and statistics and provide such data to the user.  
         [0034]     According to one method of operation, the web  110  may be advanced around the peeler member  140 , for example, by using the drive and nip roller assembly  126  to pull the web  110 . As the web  110  is advanced, the unwind roll  112  unwinds the web  110  supporting the RFID labels  102  and the rewind roll  114  rewinds the scrap web  110   a  after the RFID labels  102  have been applied or rejected. When each RFID label  102  on the web  110  is positioned within a programming range of the RFID programming system  130 , the RFID programming system  130  may program the RFID label  102  by transmitting radio frequency (RF) programming signals to the RFID label  102  and attempting to read the RFID label  102 . The RFID label  102  may then be advanced around the peel tip  142  of the peeler member  140  to remove the RFID label  102 . A removed RFID label  102   a  may then be applied to an item  104  using the tamp assembly  150  or may be rejected using the label reject assembly  160 . These operations may be repeated for each of the RFID labels  102  on the web  110  and the items  104  may be advanced such that programmed RFID labels  102  are applied to each of the items  104 .  
         [0035]     One embodiment of a RFID label  102  is shown in greater detail in  FIG. 2 . The RFID label  102  may include an integrated circuit (IC) chip  202  coupled to an antenna  204 . The IC chip  202  and antenna  204  may be sandwiched between one or more layers or substrates, such as an adhesive substrate  206  and a printable layer  208 . The adhesive substrate  206  may include a scrim coated on each side with an adhesive, such as an acrylic based adhesive. The printable layer  208  may be made of a thermal transfer paper or other material suitable for printing. One or more additional layers or substrates may also be incorporated into the RFID label  102 , as is known to those skilled in the art. The web  110  may be made of a paper with a release agent such as wax or silicone to allow the RFID label  102  to peel away from the web  110 . The RFID label  102  may have a peel adhesion strength (e.g., about 15 N/inch) that allows the RFID label  102  to be removably adhered to the web  110  and later adhered to the items  104 . Although RFID labels may have various sizes, one example of the RFID label  102  may be about 3 in. by 3 in. and supported on a web  110  having a width of about 4 in.  
         [0036]     One example of a RFID label  102  is the “Combo EAS/RFID Label or Tag” disclosed in U.S. Provisional Patent Application Ser. No. 60/628,303, which is fully incorporated herein by reference. Other examples include the RFID labels commercially available under the name Sensormatic® from Tyco Fire and Security. Those skilled in the art will recognize that the RFID label  102  may include any RFID device capable of being adhered or otherwise secured to articles or items.  
         [0037]     Referring to  FIG. 3 , one embodiment of a peeler member  140   a  is described in greater detail. The peeler member  140   a  may include a RFID programming antenna  132  integrated with the peeler member  140  and connected to a RFID reader/programmer  134 . Each RFID label  102  may thus be programmed and verified just before peeling the label and transferring the label to the tamp pad  152  (see  FIG. 1 ). The proximity of the RFID programming antenna  132  to the peel tip  142  allows each defective RFID label to be handled immediately (i.e., without having to track defective labels from a point of detection to a point of application further downstream), which may ensure that defective labels are subject to rejection and programmed labels are applied to items.  
         [0038]     According to one embodiment, the RFID programming antenna  132  may be a near-field probe such as the type disclosed in U.S. Provisional Patent Application Ser. No. 60/624,402, which is fully incorporated herein by reference. The programming range of a near-field probe is generally the near-field zone of the antenna or probe. The near field probe may be implemented by enhancing the magnitude of the induction field within the near-near field zone associated with an antenna structure and decreasing the magnitude of the radiation field within the far-field zone associated with the antenna structure. One embodiment of the near field probe may include a stripline antenna terminated into a 50 ohm chip resistor. In one example, the near field probe may have an operating frequency of 915 MHz and the near-field zone may be approximately 5 cm from the probe. One example of the probe may be about 2 to 3 in. long, although those skilled in the art will recognize that smaller probes may be used to allow programming of labels that are smaller and/or spaced closer together on the web.  
         [0039]     This embodiment of the peeler member  140   a  may include a cavity  302  in a body portion  304  of the peeler member  140   a , which is configured to receive the RFID programming antenna  132 . A cover  306  may be used to cover the cavity  302 . The cover  306  may be made of, or at least coated with, a non-reflective material that will not reflect or absorb the radio frequency waves transmitted by the RFID programming antenna  132  and the RFID device antenna  204 . For example, the cover  306  may be made of a plastic material such as the type available under the name Delrin™. A cable  308  may connect the RFID programming antenna  132  to the RFID reader/programmer  134 . The cable  308  may extend from the RFID programming antenna  132  through one side  310  of the body portion  304  of the peeler member  140   a.    
         [0040]     The RFID programming antenna  132  may be positioned within the cavity  302  such that the RFID programming antenna  132  transmits radio frequency (RF) programming signals to a RFID label  102   b  positioned over the RFID programming antenna  132  (i.e., within the programming range). The cavity  302  may include an adjustment region  312  that allows the RFID programming antenna  132  to be adjusted laterally within the cavity  302  to accommodate different sizes of labels. For example, the RFID programming antenna  132  may be configured initially to align with the IC in labels having a certain size (e.g., 3 in. by 3 in.) and may need to be adjusted laterally for labels that are smaller or larger. In one example, the lateral adjustment of a probe having a length of about 2 to 3 in. may be in a range of about 1 to 1.5 inches in either direction. An adjustment mechanism, such as a bar or rod  320 , may be coupled to the RFID programming antenna  132  to provide mechanical adjustment.  
         [0041]     Although the described embodiment shows the RFID programming antenna  132  located inside of the cavity  302  in the peeler member  140   a , the RFID programming antenna  132  may also be integrated with the peeler member  140   a  in other ways. For example, the RFID programming antenna  132  may be mounted anywhere such that an RFID label  102   b  on the peeler member  140   a  is within the programming range (e.g., the near field) of the programming antenna  132 .  
         [0042]     According to one method of programming RFID labels, the web  110  may be advanced along the peeler member  140   a  until a RFID label  102   b  is positioned within a programming range of the RFID programming antenna  132 . The RFID label  102   b  may be positioned, for example, by stopping advancement of the web  110  when a label sensor (not shown) senses an edge of the RFID label  102   b . When positioned, RF programming signals may be transmitted to the RFID label  102   b  from the RFID programming antenna  132 . RF signals may also be transmitted from the RFID label  102   b  to the RFID programming antenna  132  in an attempt to read and validate the RFID label  102   b . If the RFID label  102   b  cannot be read or validated, the RFID reader/programmer  134  may indicate that the RFID label  102   b  is defective. After the RFID label  102   b  is either programmed or determined to be defective, the web  110  is advanced along the peeler member  140   a  until the next RFID label  102  is located in the programming range of the RFID programming antenna  132 .  
         [0043]     A programmed RFID label  102   a  may be subsequently removed as the web  110  supporting the programmed RFID label  102   a  passes around the peel tip  142 . In this described embodiment, the programmed RFID label  102   a  is removed when the next RFID label  102   b  is positioned in the programming range. The next RFID label  102   b  may be programmed after the programmed RFID label  102   a  is applied to an item or may be programmed while the programmed RFID label  102   a  is applied to an item.  
         [0044]     Referring to  FIGS. 4A-4C , one embodiment of the label reject assembly  160  is described in greater detail. The accumulation pad  162  may include at least a substrate that is sufficiently rigid to receive and adhere to a rejected RFID label applied by the tamp pad  152 . The reject driving mechanism  164  may be mounted in any location that enables the accumulation pad  162  to be driven into a path  400  of the tamp apply stroke (i.e., between the tamp pad  152  and the item  104 ) and then withdrawn such that the tamp pad  152  will clear the accumulation pad  162  and the rejected label(s) on the accumulation pad  162 .  
         [0045]     The accumulation pad  162  may be configured to receive multiple rejected RFID labels stacked on previous rejected labels. The accumulation pad  162  may also be configured to receive rejected labels adjacent to other rejected labels (e.g., multiple adjacent stacks). The accumulation pad  162  may be sized according to the size of the labels and the manner in which the labels are accumulated (e.g., one stack or adjacent stacks) on the accumulation pad. For example, an accumulation pad  162  may have a size that is capable of adhering to and receiving at least one label or may have a size that is capable of receiving multiple adjacent stacks of labels.  
         [0046]     The accumulation pad  162  may include a low surface energy medium, such as polytetrafluoroethylene, at least on the surface of the accumulation pad  162 , which allows the accumulated RFID label(s) to be easily removed by peeling away the. bottom label. The accumulation pad  162  may also include a removable layer, such as an index card material, to allow the accumulated RFID label(s) to be removed.  
         [0047]     According to one method of rejecting RFID labels, the RFID labels  102  on the web  110  maybe programmed prior to passing the web  110  around the peel tip  142  of the peeler member  140 , for example, as described above. Programming the RFID labels may include detecting any defective RFID labels that should be rejected. A RFID label  102   a  that is properly programmed may be removed and applied to an item ( FIGS. 4A and 4B ). Upon detecting a defective RFID label  102   c , the label accumulation pad  162  may be extended from a retracted position ( FIGS. 4A and 4B ) to an extended position ( FIG. 4C ) into the path  400  between the tamp pad  152  and the item  104 . In the extended position, the label accumulation pad  162  prevents a full tamp apply stroke down to the item  104  and thus intercepts the rejected RFID label  102   c  before the rejected RFID label  102   c  is applied to an item  104 . The tamp pad  152  may apply the rejected RFID label  102   c  to the accumulation pad  162  in the same manner as applying labels to items  104 , as described in greater detail below. The accumulation pad  162  with the rejected RFID label(s)  102   c  applied thereto may then be retracted and normal label application may continue.  
         [0048]     The accumulation pad  162  may also be extended to different positions within the path  400  of the tamp apply stroke such that labels are received on the accumulation pad  162  adjacent to other labels. The controller  170  may control the reject driving mechanism  164  to control positioning of the accumulation pad  162  such that labels are positioned in an organized fashion (e.g., spread evenly) on the accumulation pad  162 .  
         [0049]     The accumulated rejected RFID labels may be removed from the accumulation pad  162  after a number of rejected labels accumulate on the accumulation pad  162 . The number of accumulated rejected labels may be monitored. According to one method, a numeric reject number may be printed (e.g., using an integrated printer) on the surface of a rejected label  102   c  and a reject label counter (e.g., in the controller  170 ) may be incremented. The controller  170  may provide an indication to the user as to when the accumulated labels should be removed. When the stack of accumulated labels is removed, the last numeric reject number on the top accumulated label will signify the sum of the accumulated labels in the stack, for customer recording purposes.  
         [0050]     In one embodiment, about twenty (20) to thirty (30) labels may be accumulated on the accumulation pad  162  before removing the labels. One embodiment of the RFID label applicator  100  may have a label programming failure rate of about 5%. In other words, about 5 out of every 100 RFID labels may be rejected as defective, which allows about 400 to 600 RFID labels to be applied before the stack of accumulated labels is removed. The label reject assembly  160  thus allows labels, such as defective RFID labels, to be rejected (i.e., not applied to an item  104 ) with minimal or no interruption to the label application process. Alternatively, a rejected RFID label may be removed from the accumulation pad  162  after each rejected label is intercepted by the accumulation pad  162 .  
         [0051]     An alternative embodiment of a label reject assembly may include the extendable path altering mechanism  500  shown in  FIGS. 5A and 5B . The extendable path altering mechanism  500  is extendable from a retracted position ( FIG. 5A ) to an extended position ( FIG. 5B ). In the extended position, the extendable path altering mechanism  500  may alter a path of the web  110  around the peel tip  142 , effectively enlarging the radius of the peel tip  142 . As a result, a rejected RFID label  102   d  passing around the peel tip  142  does not peel away from the web  110  and continues moving with the scrap web  110   a  instead of being applied to an item. Rejected RFID labels, such as defective RFID labels, may thus be handled automatically with minimal or no effect on the application process.  
         [0052]     The extendable path altering mechanism  500  may include an extendable tip  502  coupled to a tip driving mechanism  504 . The extendable tip  502  may be rounded with a larger radius than the peel tip  142 . In one example, the radius of the extendable tip  502  may be in a range of about 0.25 to 0.5 in. The extendable tip  502  may be made of plastic, aluminum or other suitable material that allows the web  110  to slide around the extendable tip  502 . The tip driving mechanism  504  may include a pneumatic actuated air cylinder, although those skilled in the art will recognize that other linear actuators or driving mechanisms may be used.  
         [0053]     In one embodiment, the extendable path altering mechanism  500  may be integrated with another embodiment of the peeler member  140   b . The peeler member  140   b  may include a cavity  510  for receiving the extendable path altering mechanism  500 . Alternatively, the extendable path altering mechanism  500  may be located adjacent to the peeler member  140   b  as long as the extendable tip  502  can extend to alter the path of the web  110  in a manner that will prevent a label from peeling away. The peeler member  140   b  may also include the RFID programming antenna  132  integrated with the peeler member  140   b , for example, as described above.  
         [0054]     According to one method of rejecting RFID labels using the extendable path altering mechanism  500 , a RFID label  102   b  on the web  110  may be programmed prior to passing the RFID label around the peel tip  142  of the peeler member  140   b , for example, using the integrated RFID programming antenna  132 . Programming the RFID label  102   b  may include detecting whether or not the RFID label  102   b  is defective, e.g., by attempting to read information programmed thereon. A RFID label  102   a  that is properly programmed is caused to peel away from the web  110  as the web  110  and the RFID label  102   a  passes around the peel tip  142  of the peeler member  140   b . Upon detecting a defective RFID label  102   d , the path of the web  110  around the peel tip  142  may be altered using the extendable path altering mechanism  500 , for example, by extending the extendable tip  502  beyond the peeler tip  142 . When the extendable tip  502  is extended, the web  110  may be advanced to position the next RFID label  102  for programming and/or application and the rejected RFID label  102   d  passes around the extendable tip  502  and remains on the scrap web  110   a  instead of being applied to the tamp pad  152 . The extendable tip  502  may then be retracted and normal label application may continue.  
         [0055]     To allow the path of the web  110  to be altered, the tension in the web  110  may be released such that the scrap web  110   a  unwinds and the position of the RFID label  102   b  can be maintained on the peeler member  140   b . The tension in the web  110  may be released, for example, by releasing a torque brake on a motor driving the web rewind roll and/or releasing the drive and nip roller assembly.  
         [0056]     Referring to  FIGS. 6A and 6B , another embodiment of the tamp assembly  150   a  is described in greater detail. The tamp assembly  150   a  may include a vacuum tamp pad  600  coupled to an air manifold  602 . The vacuum pad  600  may include one or more vacuum holes  610  extending through the vacuum pad  600  to a label contacting side  612 . The manifold  602  may include an inlet/outlet  620  and at least one air chamber  622  located over the vacuum holes  610  in the vacuum pad  600 . The inlet/outlet  620  may be coupled to an air supply or compressor, which may be switched between compressed air and a vacuum. When a vacuum is applied, air may be drawn through the inlet/outlet  620  and the chamber  622  in the manifold  602 , which causes air to be drawn through the vacuum holes  610  in the vacuum pad  600 . As a result, a vacuum pressure is generated around the vacuum holes  602  on the label contacting side  612  of the vacuum pad  600 , which is sufficient to hold the label  102  against the vacuum pad  600 .  
         [0057]     As shown in  FIGS. 7A-7C , the vacuum tamp pad  600  may include slots or channels  614  extending along the label contacting side  612  to promote air discharge when the vacuum is drawn. The slots or channels  614  may also provide for less friction against a label when transferring the label to the tamp pad  600  (e.g., in the label feed direction  604 ). The vacuum tamp pad  600  may also include a relief area  616  configured to receive the portion of the RFID label with the IC chip. The relief area  616  protects the IC chip from stresses due to abrasion during label transfer to the pad  600  and protects the IC chip from compressive stresses during tamp placement of the RFID label onto an item or product. The vacuum tamp pad  600  may further include a chamfer  618  at a leading edge  617  of the vacuum tamp pad  600  to promote easy label transfer to the tamp pad  600 , as the label moves in the label feed direction  604  from the peeler member.  
         [0058]     The embodiment of the vacuum tamp pad  600  shown in  FIGS. 7A-7C  is designed for a 3 in.×3 in. RFID label. For this example, the vacuum pad  600  may have a length l of about 3.125 in., a width w of about 3.00 in. and a thickness t of about 0.25 in. The tamp pad  600  may be made of a plastic material, such as the type available under the name Delrin, or other suitable materials.  
         [0059]     This described embodiment of the vacuum pad  600  includes four (4) vacuum holes  610   a - 610   d . The vacuum holes  610   a - 610   d  may be located to minimize the effect of label bow or curl and to allow each of the vacuum holes  610   a - 610   d  to be sealed regardless of the amount of label bow, thereby effectively holding the label on the vacuum pad  600 . For example, the holes  610   a  and  610   c  may be located in from the leading edge  617  about ¼ of the length of the vacuum pad  600  and the holes  610   b  and  610   d  may be located in from the leading edge  617  about ¾ of the length of the vacuum pad  600 . The holes  610   a  and  610   b  may be located in from the side edge  619  about ⅓ of the length of the vacuum pad  600  and the holes  610   c  and  610   d  may be located in from the side edge  619  about ⅔ of the length of the pad  600 . The holes  610   a - 610   d  may have a diameter of about 0.093″.  
         [0060]     The vacuum pad  600  and/or manifold  602  may be mounted to a mounting block  630  with one or more compression springs  632  positioned therebetween ( FIG. 6A ). The compression springs  632  may compress as needed when the vacuum tamp pad  600  contacts a product, allowing the tamp pad  600  to mate parallel with a surface of an item or product to which a label is being applied. The mounting block  630  may include tapered holes  634  that receive shoulder bolts  636 , which secure the compression springs  632  and allow the compression springs  632  to compress. Although the described embodiment shows four (4) compression springs  632 , any number of compression springs may be used to provide the desired compression, as may be determined by one of ordinary skill in the art.  
         [0061]     A proximity sensor  640  may also be mounted to the manifold  602  or to the vacuum tamp pad  600  to detect the surface of the item or product to which the label is to be applied. The proximity sensor  640  may thus enable consistent compression of the compression springs  632  when labels are being applied to items or products having surfaces at different levels.  
         [0062]     The tamp assembly  150  may also include a cylinder  650 , such as a pneumatic actuated air cylinder, and rod  652  for providing the linear driving force. A cylinder mounting block  654  may be used to mount the mounting block  630  to the rod  652 . Those skilled in the art will recognize that other linear actuators or driving mechanisms may also be used.  
         [0063]     According to an alternative embodiment, shown in  FIGS. 8A and 8B , a vacuum tamp pad  800  may include only three vacuum holes  810   a - 810   c . A manifold  802  with an inlet/outlet  820  may be coupled to the tamp pad  800  to cause air to pass through the vacuum holes  810   a - 810   c . The vacuum holes  810   a - 810   c  may be positioned such that the leading portion of a RFID label  102  is secured by the vacuum force when the RFID label  102  is properly positioned. The trailing portion of the RFID label  102  may be left free (i.e., not subject to a vacuum) to relieve bow in the label  102 . The vacuum hole  810   c  near the far edge of the RFID label  102  may act as a label stop. The vacuum holes  810   a - 810   c  thus take into account the natural bow that is inherent to RFID labels that are provided in roll format.  
         [0064]     A fixed stop  808  may be positioned adjacent the vacuum pad  800  to allow the label to feed (i.e., in the feed direction  804 ) and orient properly. When the RFID label  102  is being fed to the side of an item (e.g., a box) at a 90 degree angle relative to a vertical plane (i.e., sideways), the fixed stop  808  may prevent a gravity force  806  from misaligning the RFID label  102  with respect to the vacuum pad  800 . The fixed stop  808  may be fixed (e.g., bolted) to a bottom side of the tamp driving mechanism or cylinder.  
         [0065]     The vacuum holes  810   a - 810   c  may also be positioned to hold the RFID label  102  in place without subjecting the IC chip  202  in the RFID label  102  to vacuum forces at the holes  810   a - 810   c . The vacuum pad  800  may also be recessed (not shown) in the area receiving the IC chip  202  to provide additional relief. The vacuum pad  800  may also include a compressible material, to avoid damage to the IC chip  202  in the RFID label  102 .  
         [0066]     While the principles of the invention have been described herein, it is to be understood by those skilled in the art that this description is made only by way of example and not as a limitation as to the scope of the invention. Other embodiments are contemplated within the scope of the invention in addition to the embodiments shown and described herein. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the invention, which is not to be limited except by the following claims.