Abstract:
An animal ear tag including a female opening through which a head of a stem of a coupling member can pass to effect a coupling action when installing the tag on an animal, the female opening being formed as part of a separate enclosed boss component of hard material, the boss component having a flange extending peripherally from an external surface thereof, the flange being located within resilient material forming a part of the ear tag sized to anchor the boss component to the tag.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to an animal ear tag. 
     It is well known to provide an animal ear tag having a coupling arrangement which incorporates a headed stem which is forced through an animal&#39;s ear and through an opening in a female part of the tag which is located at the side of the ear opposite to that through which the headed stem is forced. A secure coupling of the tag to the animal&#39;s ear is required to ensure that the ear tag remains in place in the animal&#39;s ear. Therefore, the coupling should be of a type which resists decoupling, especially when the tag becomes snagged in an obstruction such as a fence, gate, etc. Also, it is desirable to provide an ear tag construction which is such as to resist the tag being removed and reused for illicit retagging of animals. The ear tag, therefore, needs as far as possible to be tamperproof. 
     Over the years, various attempts have been made to render an ear tag tamperproof. To this end, there has been previously proposed an ear tag construction of a type described and claimed in New Zealand patent specification 213378 in which a collar is located within an enclosed boss which surrounds the opening in the female part of the tag. When the tag is installed in the ear of an animal, the headed stem is forced through the opening and locates within the collar inside the enclosed boss. Good retention characteristics are exhibited by the tag. Furthermore, access to the head is rendered difficult if an effort is made to cause the head to be forced back out through the female opening to achieve decoupling of the tag and thereby permit the tag or one or both of the components to be illicitly reused. 
     It was also proposed that the retention characteristics be such that applying a retraction or pulling force to the stem of the tag (when endeavouring to pull the tag apart) the head would separate from the stem and remain in the collar. This would thereby render the tag/tag components non-reusable. 
     SUMMARY OF THE INVENTION 
     The tag described in New Zealand patent specification No 213378 largely achieved its objectives. However, the object of the present invention is to provide an animal ear tag which has improved tamperproof characteristics. 
     Broadly, according to one aspect of the present invention, there is provided an animal tamperproof ear tag including a female opening through which a head of a stem of a coupling member can pass to effect a coupling action when installing the tag on an animal, the female opening being formed as part of a separate enclosed boss of rigid hard moulded material with a thick wall section, the having a flange extending peripherally from an external surface thereof, said flange being moulded into the resilient material forming a part of the ear tag so as to anchor said boss to the tag part, wherein the female opening is of decreasing cross-sectional area from an external part of the boss as it extends into the cavity, said female opening being at least part formed by a plurality of projections which extend inwardly from the exterior of the boss and form at the distal ends thereof a retention surface which, in use, engages with the head of the stem of said coupling member and wherein the boss component has an internal cavity in which the head can reside after passing through the female opening, the internal cavity being in close conformity with the head of the stem. 
     Preferably the boss is made of two separate sections, a top section which has a peripheral flange and an open end which provides a shoulder, an a base section which includes a peripheral flange and incorporates the projection in female opening, a peripheral wall of the base section engaging in said open end in a snug fit with the end of the peripheral wall butted up to said shoulder, the peripheral flanges being mated face to face. 
     In the preferred form of the invention the material is a resilient material and the boss includes anchoring means for anchoring the boss component with said resilient material. The anchoring means can be formed by a plurality of openings in the flanges. 
     The hard material can be a fibre reinforced plastics material. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a face view of the female component of a two-piece ear tag incorporating the present invention, 
     FIG. 2 is a cross-sectional view on line A—A of FIG. 1, 
     FIG. 3 is an elevation view of the boss portion of the female component of the tag as illustrated in FIGS. 1 and 2, 
     FIG. 4 is a cross-sectional view taken on line B—B of FIG. 3, 
     FIG. 5 is a bottom plan view of the boss as shown in FIGS. 3 and 4, 
     FIG. 6 is a plan view of a top section of a further embodiment of the boss portion. 
     FIG. 7 is a similar view to FIG. 6 by showing a base section of the boss portion, 
     FIG. 8 is a cross-sectional view on line C—C of FIG. 6, 
     FIG. 9 is a cross-sectional view on line D—D of FIG. 7, and 
     FIG. 10 is a cross-sectional view of the top section and base section combined to form a complete boss portion. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is in a preferred embodiment as illustrated in the drawings applied to an animal ear tag formed of two separate components, namely, a male component  10  and a female component  11 . The male component has a stem  12  which projects from one face thereof. The male component  10  can be simply a disc from which the stem  12  extends or it can include a panel  13  as illustrated. 
     The present invention can also be applied to an ear tag of one piece construction which employs a headed stem fitting with a female opening to achieve mounting of the tag to the ear of an animal. 
     The stem  12  at its distal end includes a head  14  which in a known manner incorporates a hard material insert  15 . In known manner the pin of an applicator tool is insertable through the hollow bore of stem  12  to engage with the hard insert  15  and thereby apply a driving force to the insert  15 . This forces the insert  15  through the animal&#39;s ear drawing with it the stem  12 . 
     In accordance with known forms of ear tags, the female component  11  preferably incorporates a panel  16  on which indicia can be applied. Also, in accordance with known ear tag constructions the male and female components are preferably formed of a resilient material such as polyurethane. The use of such material results in the components  10  and  11  being flexible, thereby enabling the tag to flex upon any snagging occurring. The flexibility characteristics generally result in the tag being able to flex sufficiently so that the animal wearing the ear tag can free the tag away from a snagging obstacle rather than ripping the tag from the animal&#39;s ear. 
     According to the present invention, the female component  11  incorporates a separate boss component  17  which is intended to receive in a snap locking arrangement the head  14  and to retain the head within the boss. According to the invention, the boss  17  is formed by, for example, moulding and is made from a rigid hard material such as nylon. In the more preferred form of the invention the nylon includes glass reinforcing fibres with, for example, the glass fibre content being about 30%. 
     The boss component  17  is pre-formed and, as will be hereinafter described, incorporated using an insert moulding technique with the female component  11 . Manufacture of the boss  17  can be carried out by moulding in an injection moulding process the boss about a metal core. After moulding the boss will include the metal core. However, the core will be formed from a material which is meltable at a temperature elevated beyond that which would normally be experienced during the injection moulding process. Therefore, upon moulding being completed, the boss with contained metal core would be conveyed to a melting tank in which the metal core would be melted out of the boss. By way of example, the melting tank could be at a temperature of about 185° C. The boss component would then be transferred to a rinsing tank and subsequently to a drying facility. The thus completed boss would then be ready for moulding into the female component. It is anticipated that one suitable metal for this process is bismuth or a bismuth and tin combination. 
     The boss  17  is moulded with at least one peripheral flange  18  located at or adjacent one end thereof. This is the end through which the head  14  is forced. This flange  18  includes anchorage means which in the preferred form of the invention comprises a plurality of openings  19 . 
     The boss  17  is as previously mentioned pre-formed. It is then placed into a moulding tool and the female component  11  is moulded such that part of the boss  17  including the flange  18  is moulded into the plastics material from which the female component  11  is moulded. As a consequence of this plastics material will flow into openings  19  so as to increase the anchorage of the boss  17  in the tag material. Other anchorage means could be employed within the scope of the invention. 
     The boss  17  incorporates an internal cavity  20  which in the preferred form is shaped to be commensurate with the external shape of the head  14  of the male component but with sufficient clearance to enable the head  14  to move sufficiently into the cavity to permit a correct locking action as will hereinafter be described. The cavity  20 , however, is only sufficient in volume to accommodate a single head within the boss  17 . 
     An opening  21  into the cavity  20  is provided. This preferably is of truncated conical shape as can be seen in FIGS. 2 and 4. Slits or slots  22  are formed in the wall which defines the truncated conical shaped opening  21  thereby resulting in a plurality of inclined projections  23 . In an alternative arrangement the slits or slots could be replaced by weakened sections or areas by deliberate thinning of the wall thickness at selected positions. The slots  22  do not pass through the exterior of the boss as can be seen in FIGS. 4 and 5. 
     Even though the boss  17  is formed of a rigid and hard material and the slots are closed at one end the slots  22  (or weakened sections), nevertheless, enable the projections  23  to flex or move as the head  14  is forced through opening  21  and into cavity  20 . However, once the head  14  is located in position within the cavity  20  the projections become restored to their normal state and engage in behind the shoulder  14   a  of the head  14 . As shown in FIG. 2, the projections  23  more preferably engage into the area defined by the joining of shoulder  14   a  and the adjacent external surface of the stem  12 . 
     The projections  23  surrounding the underside or shoulder  14   a  of the head  14  provide a positive coupling with the head  14  so that once installed the head cannot be pulled back out of cavity  20 . Therefore, the retention properties are extremely good and indeed any reverse pull on the stem  12  will only tend to increase the locking effect of the projections  23  on the stem/head. It is therefore envisaged that a pulling action or retraction force applied to stem  12  if sufficiently high will result in the stem fracturing, thereby rendering male component  10  unusable. However, stem  12  could include in its length, and possibly adjacent head  14 , a waisted portion to further increase the possibility of fracture. This waisting should not be such that in normal use a force resulting from snagging will cause the stem to fracture. 
     If the stem  12  fractures/separates, the head  14  will remain in cavity  20 . Due to the close conformity of the cavity  20  with the head  14  it will not be possible for the female component  11  to be reused as there will be insufficient space in the cavity  20  to accommodate a second head. Furthermore, the rigid nature of the boss  17  is such that the boss will not be able to bulge or deform and thereby accommodate a second head in the event that an effort is made to combine a further male component  10  with the female component. 
     The thick wall section and the nature of the material forming the boss  17  will also prevent any force being applied to the head  14  in an effort to force it back out through opening  21 . Thereby a force applied to head  14  from externally of the boss  17  will not be able to be used to either force the head  14  out of the boss  17  to decouple the tag component or indeed where a head portion resides in the cavity (due to the stem fracturing) to force the head  14  out so that another male tag component can be used to illicitly reinstall the female component  11 . 
     The invention is open to modification within the scope of the present disclosure. For example, even though the retention means for retaining the head within the boss is disclosed herein as being formed as part of the boss, it could be a separate element which is combined with the boss and/or body of the female component or is formed during moulding of the female component. Also, while the boss is preferably moulded in one piece the end opposite the female opening could be left open. If left open a cover piece could be fastened thereover and fixed in place as a post moulding operation. 
     An alternative embodiment of the boss is illustrated in FIGS. 6 to  10  where the boss is formed by two separate sections  25  and  26 . The top section  25  has a peripheral flange  18   a  and an open end  27  which provides a shoulder  28 . The lower or base section  26  includes a peripheral flange  18   b  and incorporates the projections  23  and opening  21 . A peripheral wall  29  engages (see FIGS. 10) in open end  27  in a snug fit with the end  30  of wall  29  butted up to shoulder  28 . The flanges  18   a  and  18   b  mate face to face. 
     Flanges  18   a  and  18   b  include openings  19  which are of an elongate form rather than the circular form of the first embodiment. The top section  25  and base section  26  when combined are located such that the openings  19  of flanges  18   a  and  18   b  are aligned or at least overlap. 
     The top section  25  and base section  26  can be injection moulded in a hard grade of polyurethane (TPU). Both parts are assembled, as shown in FIG. 10, before being placed within the cavity of the female mould prior to moulding. The over moulding of the tag panel material can then be performed using the traditional grades of TPU. The over moulding will retain the boss  17  as well as fix the top section  25  and base section  26  together. 
     With the tag of the present invention it is believed that the force required to apply the head  14  of the male component  10  through the opening  21  and into the boss will be less relative to the level of retention of the head when installed in the boss than comparable tags. The inwardly tapering opening  21  will provide good lead in characteristics for the head as it approaches the cavity and the deformity of the projections  23  will be able to occur without applying unnecessary force to the insert  15  of the head  14  which may otherwise result in the insert separating from the head and thereby leading to misapplication. It is also believed that the tag during the installation procedure will provide a clean cut through the ear of the animal. 
     Nevertheless, once the head is in position the engagement of the projections behind the head will ensure that the head is held in place with high retention levels. This is achieved without the need for the shoulder  14   a  of the head to be inclined backwardly relative to the distal or pointed end of the insert which is a technique which has been used previously to try and increase retention of the head by the female component. 
     The ear tag also permits the head and stem of the male component to rotate relative to the female component. This is achieved because of a clearance which exists between the head and the boss cavity and between the stem and the inclined projections. 
     It is believed that it may be possible that any deformation of the shoulder area  14   a  of the head when a retraction or pulling force is applied to the stem (such deformation being caused by the interaction with the distal or free edge of the projection  23 ) will enhance rather than lessen the level of retention. As the interaction between the end of the projections is directed toward the internal flange of the insert  15  it is believed that any deformation of the head will not be such as to reduce the overall cross-sectional dimension of the head and thereby enable the deformed head to escape back through the opening as defined by the distal ends of the projections  23 . 
     The boss being formed of a rigid material will also ensure that the boss cannot be deformed either radially or longitudinally or in such other manner as to manipulate the head and/or the opening/retention projections to enable the head to be forced from within the cavity  20 . 
     The moulding of the boss in one piece provides a benefit in that there is no need for a separate fabrication step after moulding of the female component in order, for example, to apply an end cap to the boss to enclose the boss cavity. Therefore, the construction of the tamperproof coupling is not dependent upon the quality achieved with a separate joining or fabrication process. 
     It is therefore believed that an animal ear tag incorporating the present invention will exhibit extremely good tamperproof characteristics and render ear tag components which have been used unsuitable for reuse.