Abstract:
A SIM module includes a SIM and a plastic support on which the SIM is attached. A discontinuity channel between the plastic support and the SIM is formed all around the SIM, the discontinuity channel being interrupted in at least two points of the plastic support attaching the SIM to the plastic support. The points are on a short side and on a long side of the SIM.

Description:
FIELD OF INVENTION 
     The present invention relates to a Subscriber Identity Module (SIM) and a plastic support whereto the SIM is attached and from which the SIM is detached for usage. More particularly, the invention relates to the structure of a SIM module and to a method for manufacturing it. 
     BACKGROUND OF THE INVENTION 
     As known, a SIM is so small that it is attached to a plastic support when it is released from a factory. The SIM and the respective plastic support are also referred to as SIM module. The consumer of the SIM buys the SIM module and detaches the SIM from the plastic support, for usage. For facilitating the detachment, the SIM is attached to the plastic support by one or more precut lines. 
       FIG. 1A  schematically shows a SIM module with punching holes and precut lines. A card body  110  includes a SIM  115 , a mini SIM or micro SIM. Two punch holes  120 ,  125  on the left and right side of the SIM  115  and two pre-cut lines  130 ,  135  on top and bottom side of the SIM  115  are provided for facilitating its detachment from the plastic support of the SIM module.  FIG. 1B  and  FIG. 1C  schematically show the manufacturing process of the SIM module. The SIM  115  is formed on the plastic support of the module  110  as one part. Then, the target cutting boundary S 1 , S 2  are made, based on the plastic support size and the SIM size and the respective position. The area is usually pre-calculated and it can be corrected based on the error of the manufacturing process. 
     A portion of the left and right side of the SIM module are removed by a punching process as depicted in  FIG. 1C . After the punching process, left hole  125  and right hole  120  are formed just near the SIM  115 . In this state, the target cutting boundary S 1 , S 2  still remains on top and bottom side of the SIM  115 . The target cutting boundary S 1 , S 2  needs to be processed to form on the top and bottom sides of the SIM  115  pre-cut lines. 
       FIG. 2A  shows the cross section of the blades used at the pre-cut process. Top blade  200  and bottom blade  210  enter the plastic support  110  and form the pre-cut lines moving along the target cutting boundary. In  FIG. 2A , the top blade  200  and the bottom blade  210  are arranged symmetrically based on the central plane  110  of the support. 
     Due to the symmetry of the blades, the final product with the pre-cut line can obtain reliability and easily detachable characteristics. However, a precise symmetry can be obtained in an exceptionally ideal situation. In the real manufacturing process, there is asymmetry on the top blade  200  and the bottom blade  210 , caused by undesirable and unpredictable circumstances. 
       FIGS. 2B, 2C, and 2D  schematically illustrate examples showing the asymmetry occurring on the top and bottom blades. In  FIG. 2B , the bottom blade  210  penetrates the central plane  220 , which causes a deeper bottom pre-cut line on the full-sized card  110 . In  FIG. 2C , the top blade  200  penetrates the central plane  220 , which causes a deeper top pre-cut line on the full-sized card  110 . In  FIG. 2D , the top blade  200  and the bottom blade  210  are not aligned in a line, which causes top pre-cut line and bottom pre-cut line to be formed asymmetrically in a different position. These kinds of errors happen frequently and are difficult to detect. 
     Moreover, the asymmetrical pre-cut lines cause overbalanced stress distribution on the SIM  115  and local bending. The bending introduces stress localized on the micro-module of the SIM and causes problems during card transport on the next process. In an extreme case where a pre-cut line is absent or is formed ineffectively, it may cause damage during the plug-in detach. 
     Other technical problems may be associated with the pre-cut line area. More particularly, the manufacturing process requires two process steps, which is more costly. The blade penetration is a mechanical process, and thus the production is frequently impacted from the blade stopping in it&#39;s rail, due to the powder or loss of lubrication. Furthermore, it is not easy to detect the asymmetrical pre-cut line before doing a destructive mechanical test. Continuous changing of blades, rail cleaning, and fine tuning adjustments may increase the production cost. 
     French patent No. 2806661 suggested a SIM having three linking pieces which are connected to the plastic support. Two of the three linking pieces are disposed on one side of the SIM and the other is disposed on the opposite side of the SIM card. The two linking pieces are disposed symmetrically on the other opposite side&#39;s linking piece. Although it is not drawn clearly in the  FIG. 2 , the linking pieces of the bottom side each have a pre-cut, to let the SIM be detached from the plastic support. 
     Moreover, since the SIM comprises three linking pieces, one of which is arranged in the opposite side from the other two linking pieces, the consumer should apply a strong force to break at least one of the linking pieces at first. 
     SUMMARY OF INVENTION 
     The problem addressed by the present embodiments is to provide a SIM module and a corresponding method to manufacture it, wherein a SIM of the module is safely attached to a respective plastic support of the module, this having a structure facilitating the detachment of the SIM, with little force applied on the SIM, to prevent possible damage on the respective electrical components. 
     An object of the present embodiments is to simplify the manufacturing of a SIM module by forming a discontinuity channel which separates the plastic support from a respective SIM and leaving only two points of the plastic support, in the channel, for attaching the SIM to the support, such point being easily broken and without applying strong forces on the SIM, for detaching the SIM. Advantageously, precut lines are avoided in the manufacturing process and the detachment of the SIM is facilitated. 
     More particularly, the technical problem reported above is addressed by a SIM module including a SIM and a plastic support on which the SIM is attached, wherein a discontinuity channel between the plastic support and the SIM is formed all around the SIM. The discontinuity channel is interrupted in at least two points of the plastic support attaching the SIM to the plastic support, wherein the points are on a short side and on a long side of the SIM. Advantageously, the position of the points avoids stresses on the chip of the SIM or on its electrical contacts, since no pressure or bending is exerted on the chip or contact for breaking the points. 
     In an aspect of the embodiments, each of the points is a converging point of a delta shaped portion of the plastic support which is arranged to remain enclosed to the plastic support when the SIM is detached. Advantageously, the wider part of the delta portion is towards the plastic support and the thinner part towards the SIM, so that the detachment of the SIM is facilitated and a precise breaking of the support in the points may be assured. 
     More particularly, in one aspect of the embodiments, a projection of the discontinuity channel is delimited within the SIM and laterally to the interrupting points, to let the plastic support be broken exactly in the points, when the SIM is detached. The form of the channel near the point improves the precision of rupture along the SIM edges and may render its detachment even easier. 
     In one embodiment, a depth of the projections in the SIM decreases at a predetermined distance from the interruption point, preferably proportionally to the distance. This shape of the discontinuity channel improves the detachability. The channel has a predetermined width, preferably between 1/7 and 1/15 of the short size of the SIM. 
     According to another aspect, a conjunction line between the two points of the support does not cross an integrated circuit of the SIM. This configuration of the points may avoid the stress on the integrated circuit, when the SIM is detached. 
     At least an additional point attaching the SIM to the plastic support may be provided. This additional point is preferably along one of the sides of the SIM not involved by the other two points. However, nothing prevents that two or more points are provided on the same side of the SIM. This configuration of points may advantageously improve the attachment of the SIM to the plastic support and thus its protection before usage, without complicating its manufacturing or detachment. 
     More particularly, the SIM is attached to a frame body of a full-sized card plastic support, the SIM being arranged in a portion of the frame body and comprising a first connecting portion disposed on a first side of the SIM card, attaching the SIM card to the frame body, a second connecting portion disposed on a second side of the SIM card, attaching the SIM card to the frame body, the second side being adjacent to the first side. A first hole surrounds a portion of the SIM card arranged between the first connecting portion and the second connecting portion and a second hole surrounds a portion of the SIM card arranged between the first connecting portion and the second connecting portion, wherein the first connecting portion and the second connecting portion have a pointed shape. The connecting portions form the interruption point of the discontinuity channel and the first and second holes are holes through the plastic support. 
     Since the SIM is attached to the frame body without pre-cut lines, the technical problem discussed above may be overcome. Moreover, since the SIM comprises two connecting portions with a pointed shape, it becomes easier to detach it by rotation back and forth, preferably around an axis formed connecting the two connecting portions. Less force is required to cut the SIM from the frame body of full-sized card. 
     In another aspect, in the SIM, the first side is shorter than the second side, and the first connecting portion is disposed approximately at the center of the first side. The second connecting portion is disposed on the second side at farther position from the first side than the center of the second side. The first and second connecting portions may enhance the stability of the attachment of the SIM cards. 
     In another aspect, the first connecting portion has a triangular shape whose tip is connected to the SIM. The second connecting portion may have a triangular shape whose tip is connected to the SIM. The above shape may prevent the presence of an offshoot after snapping of the SIM from the body frame of full-sized card plastic support. 
     In another aspect, the SIM has a recess formed inside the first hole near the tip of the first connecting portion and has another recess formed inside the second hole near the tip of the first connecting portion. The above shape can further prevent presence of an offshoot after snapping of the SIM from the body frame of full-sized card. 
     In another aspect, the recesses extends no longer than the bottom side&#39;s width of the triangular shape of the first connecting portions. The minimum recess size makes the lateral side of the SIM card planar and protects undesirable substances to be filled in the recess. 
     In another aspect, the SIM has a recess formed inside the first hole near the tip of the second connecting portion and has another recess formed inside the second hole near the tip of the second connecting portion. The recesses extend no longer than the bottom side&#39;s width of the triangular shape of the second connecting portions. 
     According to another aspect, a method for producing the SIM module includes forming the SIM on a frame body of a plastic support and punching the frame body so that only two points, on adjacent side of the SIM, attach the SIM to the support. 
     Further advantages and features of the method and SIM module according to the present invention will be apparent from the description given here below only for exemplificative purpose and without limiting the scope of protection of the present embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a schematic diagram showing a SIM module according to the prior art. 
         FIGS. 1B-1C  are schematic diagrams representing the manufacturing process of the SIM module of  FIG. 1A . 
         FIG. 2A  is a schematic diagram showing a cross section of blades used for a pre-cut process according to the prior art method. 
         FIGS. 2B-2D  are schematic diagrams illustrating an asymmetry occurring on the top and bottom blades of  FIG. 2A . 
         FIG. 3  is a schematic diagram illustrating the SIM module according to the present embodiments. 
         FIG. 4A  is an enlarged view illustrating in greater detail the SIM module of  FIG. 3 . 
         FIG. 4B  is an enlarged view illustrating a first connecting portion of a SIM after detaching from the frame body of plastic support, according to the present embodiments. 
         FIG. 5  is a schematic diagram showing an axis on which the SIM card is snapped and detached from the frame body, according to the present embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 3  schematically represents a SIM module according to the present embodiments. A SIM  350  is attached to a frame body of a full-sized card plastic support  300 , also indicated as plastic support  300 . The SIM  350  is arranged in a portion of the frame body, for example, in a left of a half portion of the plastic support  300 . The SIM  350  comprises a first connecting portion  330  on a first side, attaching the SIM  350  to the frame body  300 . 
     The SIM  350  also comprises a second connecting portion  340  disposed on a second side of the SIM  350  and attaching the SIM  350  to the frame body  300 . The first side and second side of the SIM  350  are adjacent to each other. 
     A first hole  310  is delimited in the plastic support  300 , surrounding a portion of the SIM  350  arranged between the first connecting portion  330  and the second connecting portion  340 . The support  300  further comprises a second hole  320  surrounding another portion of the SIM  350  arranged between the first connecting portion  330  and the second connecting portion  340 , the first hole  310  being disposed in opposite position from the second hole  320 . The first hole  310  and the second hole  320  may be formed by a punching process. 
     The first connecting portion  330  and the second connecting portion  340  have a pointed shape, as no pre-cut lines are present. Preferably, the first connection portion  330  is connected to the SIM  350  with as small contact area as possible. The first side where the first connecting portion  330  is disposed is shorter than the second side where the second connecting portion  340  is disposed. Preferably, the first connecting portion  330  is disposed approximately at the center of the first side and the second connecting portion  340  on the second side at a farther position from the first side than the center of the second side. 
     The first connecting portion  330  may have a triangular shape whose tip is connected to the SIM  350 . Similarly, the second connecting portion  340  has a triangular shape whose tip is connected to the SIM  350 . This triangular shape is represented in detail in  FIG. 4A , which is a magnified view of the first connecting portion  370  of  FIG. 3 . 
     The SIM  350  has a recess  400  formed by the first hole  310  near the tip of the first connecting portion  330  and another recess  410  formed by the second hole  320  near the tip of the first connecting portion  330 . The recess can prevent presence of offshoot after snapping of the SIM from the body frame of the plastic support. The recesses  400 ,  410  extend no longer than the bottom side&#39;s width of the triangular shape of the first connecting portion  330 , as depicted in  FIG. 4A . The width of the recess  400  vertically drawn in  FIG. 4A  is smaller than the width of the base of triangle  330 . 
     In a similar way, the SIM  350  has a recess formed inside the first hole  310  near the tip of the second connecting portion  340  and has another recess formed inside the second hole  320  near the tip of the second connecting portion  340 . The recesses extend no longer than the bottom side&#39;s width of the triangular shape of the second connecting portion  340 . 
       FIG. 4B  schematically shows the magnified first connecting portion after the SIM card is detached from the frame body of the plastic support. Due to the two recesses  400 ,  410 , the offshoot  450  extends no longer than the planar line  460  which is formed parallel to the first side of the SIM  350 . As the recesses  400 ,  410  occupy small areas with respect to the SIM area, the cut side can be regarded as planar. 
       FIG. 5  schematically shows an axis on which the SIM is snapped and detached from the frame body. The SIM  350  is snapped on the axis  500  which extends from the first connecting portion  330  to the second connecting portion  340 . The customer who has bought the SIM module can snap the SIM  350  and swing it back and forth on the axis  500  several times. Then, the first and second connection portion  330  and  340  are worn out until the SIM  350  is detached from the frame body of the support  300 . 
     The SIM according to the present embodiments may be manufactured with a punching process. The SIM  350  is formed on the frame body of the plastic support  300  and then the frame body  300  is punched, so that the first and second holes  310 ,  320  are formed along the outline of the SIM  350 . Since the SIM may be manufactured by a punching process without a pre-cut, the manufacturing cost decreases. The undesirable artifact caused by the pre-cutting manufacture, such as unbalanced stress applied to the SIM card, can be prevented by the punching process. 
     Advantageously, according to the embodiments, since the SIM comprises two connecting portions with a pointed shape, it becomes easier to detach the SIM by moving it back and forth based on the axis formed by the two connecting portions. Moreover, the recess near the connecting portions prevents the presence of offshoot after snapping of the SIM from the body frame of a full-sized card. The minimum recess&#39;s size makes the lateral side of the SIM planar and protects undesirable substances from being filled in the recess. 
     Furthermore, since the SIM comprises two connecting portions with a pointed shape, it becomes easier to detach the SIM by rotating it back and forth based on the axis formed by the two connecting portions. Less force is required to detach the SIM from the frame body of a full-sized card plastic support.