IC card

Abstract: An IC card (31) of the present invention comprises a panel (4, 5) having resilient projections (25, 26) and a frame (2) having recesses (27, 28) corresponding to the resilient projections (25, 26), and the panel (4, 5) is mounted on the frame (2) by engaging the respective resilient projections (25, 26) with the respective recesses (27, 28). Thus, the panel (4, 5) can be securely attached to the panel (4, 5).

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an IC card which can improve the junction strength of a panel to a frame. Description of the Prior Art Fig. 1 is a perspective view showing an example of a conventional IC card, Fig. 2 is an exploded perspective view of Fig. 1, and Fig. 3 is a sectional view taken along the plane III-III of Fig. 1. Referring to Figs. 1 to 3, an IC card 1 consists of a rectangular frame 2, a wiring board 3, and a pair of panels 4 and 5. Electronic parts 6 such as a semiconductor memory or the like are installed on a top and a bottom surface of the wiring board 3, respectively, and a hole 7 is formed at the central part of the wiring board 3. The frame 2 is made of synthetic resin and has openings 8 in its top and its bottom surface, respectively. A convex supporter 9 for supporting the wiring board 3 is provided on an inner surface of the frame 2 along a circumferential direction, and an arm 10 having a projection 11 is provided at a central part of the frame 2 along a cross direction. A concavity 12 for supporting the panel 4 is formed in the top surface of the frame 2 along a circumferential direction, while another concavity 13 (see Fig. 3) is formed in the bottom surface of the frame 2 along a circumferential direction, similarly to the concavity 12. A plurality of electrodes 14 for inserting contact pins (not shown) are provided on an end of the frame 2. Each of the panels 4 and 5 is made of metal, and has a rectangular form. The IC card 1 is assembled as follow: First, the projection 11 of the frame 2 is passed through the hole 7 of the wiring board 3, and a peripheral part of the wiring board 3 is put on the convex supporter 9. In that state, a tip end of the projection 11 is crimped while being heated to form a crimping part 11a as shown in Fig. 4, whereby the wiring board 3 with the electronic parts 6 is installed in the frame 2 and the electrodes 14 are electrically connected with the electronic parts 6 through the wiring board 3. Thereafter, the panels 4 and 5 are glued to the concavities 12 and 13 of the frame 2 through adhesive materials 15 such as an adhesive sheet, adhesive bond or the like, respectively, whereby the panels 4 and 5 cover the openings 8 of the frame 2 while containing the wiring board 3 with the electronic parts 6 in the frame 2. With the above conventional IC card 1, the panels 4 and 5 are attached to the frame 2 only by the adhesive strength of the adhesive materials 15. As a result, it yields the problems that a gap results partially between the panels 4, 5 and frame 2 owing to the reduction of the adhesive strength with the lapse of time, or the panel 4 or 5 is partially separated from the frame 2 when the IC card 1 is bent, to thereby deteriorate the quality of the IC card 1. Document FR-A-2 586 886 discloses an IC card corresponding to the preamble of claim 1. In this IC card the frame has a protruding rib portion to which the panels are afixed by means of adhesive means. The present invention is as specified in claim 1. Accordingly, a principal object of the present invention is to provide an IC card which can improve the performance of the attachment between a panel and a frame. According to the present invention, since the panel is mounted on the frame by engaging the respective resilient projections of the panel with the respective recesses of the frame, the panel can be securely attached to the frame. And therefore, it can securely prevent the panel from separating from the frame regardless of the lapse of time and any bending operation of the IC card, which eventually makes it possible to improve the quality of the IC card. These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing an example of a conventional IC card; Fig. 2 is an exploded perspective view of Fig. 1; Fig. 3 is a sectional view taken along the plane III-III of Fig. 1; Fig. 4 is a perspective view showing the conventional IC card from which a panel is removed; Fig. 5 is a perspective view showing an embodiment of an IC card according to the present invention; Fig. 6 is an exploded perspective view of Fig. 5; Fig. 7 is a sectional view taken along the plane VII-VII of Fig. 5; Fig. 8 is a perspective view showing a resilient projection of a panel; Fig. 9 is a view, partially in cross-section, of a portion of the IC card with removed panels; Fig. 10 is a view, partially in cross-section, of another portion of the IC card with removed panels; Fig. 11 is a perspective view showing the IC card from which a panel is removed; Fig. 12 is a view, partially in cross-section, of a portion of the IC card with removed panels; Fig. 13 is a view, partially in cross-section, of another portion of the IC card with removed panels; DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 5 is a perspective view showing an embodiment of an IC card according to the present invention, Fig. 6 is an exploded perspective view of Fig. 5, and Fig. 7 is a sectional view taken along the plane VII-VII of Fig. 5. Referring to Figs. 5 to 7, each of the panels 4 and 5 is made of an elastic member such as a metal plate or the like. The rectangular panel 4 has two opposed long sides 21 and 22 and two opposed short sides 23 and 24, and resilient projections 25 are respectively provided in pairs at each of the long sides 21 and 22. As shown in Fig. 8, each of the resilient projections 25 consists of a protruding piece 25a extending from a back surface of the panel 4 along a vertical direction and a hook 25b formed by folding a top end of the protruding piece 25a at an acute angle  back toward the respective surface of the panel 4. Besides, as shown in Fig. 6, a distance L₁ between the one short side 23 and each of the one resilient projections 25 disposed at one end side of the individual long sides 21 and 25 is different from another distance L₂ between the other short side 24 and each of the other resilient projections 25 disposed at the other end side of the individual long sides 21 and 22. The reason will be described later. The panel 5 has the same construction as the panel 4 but is mounted on the frame 2 in a posture reverse to that of the panel 4. That is, resilient projections 26 similar to the resilient projections 25 of the panel 4 are respectively provided in pairs at each of the long sides of the panel 5, and distances L₁ and L₂ which represent the position of the resilient projections 26 are determined similarly to those of the panel 4. The frame 2 has four recesses 27, which are formed in one concavity 12 and which are located at the periphery of one opening 8 corresponding to the resilient projections 25 of the panel 4. As shown in Fig. 9, each of the recesses 27 comprises an entrance space 27a having a fixed narrow width W and a bottom space 27b whose inner wall 27c forms a slope so that a width of the bottom space 27b becomes larger as it goes to thebottom of the bottom space 27b. In this embodiment, the recess 27 is formed as a through hole, but the bottom of recess 27 may be closed, if desired. On the other hand, the frame 2 has four other recesses 28, which are formed in. the other concavity 13 (see Fig. 7) and which are located attire periphery of the other opening 8 corresponding to the resilient projections 26 of the panel 5. As shown in Fig. 10, each of the recesses 28 has an entrance space 28a, a bottom space 28b and an inner wall 28c similar to the entrance space 27a, the bottom space 27b and the inner wall 27c of the recess 27, respectively, but is formed in a posture reverse to that of the recess 27. As is apparent from Fig. 6, since the distances L₁ and L₂ which represent the positions of the resilient projections 25 and 26 of the panels 4 and 5 are different from each other, it is possible to form the recesses 27 and 28 at the mutual different positions of the frame 2. Since the other structure of the IC card 31 is similar to that of the IC card 1, the same reference numerals are used in the same parts, and hence further explanation thereof will be omitted. The IC card 31 is assembled as follows: First, similarly to the case of the conventional IC card 1, the projection 11 of the frame 2 is passed through the hole 7 of the wiring board 3, and the peripheral part of the wiring board 3 is put on the convex supporter 9 of the frame 2. In that state, the tip end of the projection 11 is crimped while being heated to form the crimping part 11a as shown in Fig. 11, whereby the wiring board 3 with the electronic parts 6 is installed in the frame 2 and the electrodes 14 are electrically connected with the electronic parts 6 through the wiring board 3. Next, an adhesive material 15 (see Fig. 7) such as an adhesive sheet or the like is allocated on the back surface of the panel 4, and thereafter the panel 4 is impressed on the concavity 12 of the frame 2 to insert the resilient projections 25 of the panel 4 into the recesses 27 of the frame 2. As a result, each resilient projection 25 passes through the entrance space 27a of the corresponding recess 27 while elastically deforming the hook 25b thereof toward the protruding piece 25a thereof, and then in the bottom space 27b, the hook 25b elastically returns and engages with the inner wall 27c of the bottom space 27b, as shown in Fig. 12. This engagement prevents extracting the resilient projections 25 from the recesses 27. Thus, the panel 4 is joined to the frame 2 with both the adhesive strength of the adhesive material 15 and the engagement of the resilient projections 25 and the recesses 27. Finally, the other panel 5 is joined to the concavity 13 (see Fig. 7) formed at the bottom surface of the frame 2, similarly to a case of the panel 4. Fig. 13 is a view, partially in cross-section, of a portion of the IC card 31, in which the panel 5 is joined to the frame 2 with both the adhesive strength of the adhesive material 15 and the engagement of the resilient projections 26 and the recesses 28. According to the IC card 31, the panels 4 and 5 are joined to the frame 2 with the engagement of the resilient projections 25, 26 and the recesses 27, 28 in addition to the adhesion by the adhesive materials 15. Consequently, even if the adhesive strength of the adhesive materials 15 should be deteriorated with the lapse of time, or even if the IC card 31 has been forcibly bent, the panels 4 and 5 remain securely connected to the frame 2 by the engagement of the resilient projections 25, 26 and the recesses 27, 28. In the above embodiment, although the panels 4 and 5 have been joined to be frame 2 with both the adhesive strength of the adhesive materials 15 and the engagement of the resilient projections 25, 26 and the recesses 27, 28, the adhesive materials 15 may be omitted according to circumstances. In the above embodiment, although the resilient projections 25 (26) have been respectively provided in pairs at each of the long sides 21 and 22 of the panel 4 (5), three or more resilient projections 25 (26) may be respectively provided at each of the long sides 21 and 22 of the panel 4 (5). Furthermore, the resilient projections 25 (26) may be provided at two opposed short sides 23 and 24 of the panel 4 (5) instead of two opposed long sides 21 and 22 of the panel 4 (5), or may be provided at both of two opposed long sides 21 and 22 and two opposed short sides 23 and 24 of the panel 4 (5). In the above embodiment, although the panels 4 and 5, the frame 2 and the wiring board 3 are shown as a rectangle respectively, they may be a quadrate respectively. In the above embodiment, although the frame 2 has two openings 8 which are respectively formed in the top and the bottom surface thereof and two panels 4 and 5 are mounted in the both surfaces of the frame 2, the frame 2 may have a single opening 8 which is formed in one side of the top and the bottom surface thereof and a single panel 4 or 5 may be mounted in the surface having the opening of the frame 2. Besides, the wiring board 3 may be installed to the frame 2 by a different way from that described above. Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation.

Claims: An IC-card comprising a frame (2) having an opening (8) which is formed in at least one side of a top and a bottom surface thereof, electronic parts (6) contained in the frame (2), and a panel (4, 5) mounted in the frame (2) and covering the opening (8), characterized in that the frame (2) is provided with a plurality of recesses (27, 28) located at the periphery of the opening (8), in that the panel (4, 5) is provided with a plurality of resilient projections (25, 26) located at the periphery of the panel (4, 5) at locations corresponding to the recesses (27, 28), in that each of the resilient projections (25, 26) consists of a protruding piece (25a) extending from a back surface of the panel (4, 5) along vertical direction perpendicular to the panel surface and a hook (25b) formed by folding a top end of the protruding piece (25a) back toward the respective surface of the panel (4, 5), while each of the recesses (27, 28) consists of an entrance space (27a, 28a) having a fixed narrow width (W) and a bottom space (27b, 28b) whose inner wall (27c, 28c) forms a slope so that the width of the bottom space (27b, 28b) becomes larger in the direction towards the end of the bottom space (27b, 28b) furthest from the entrance space, and in that each of the resilient projections (25, 26) is shaped so that when it is inserted into the respective entrance space (27a, 28a) the hook (25b) is elastically deformed towards the protruding piece (25a) until the hook reacher the bottom space (27b, 28b) which is shaped so that the hook (25b) can elastically return and engage with the inner wall (27c, 28c) of the bottom space (27b, 28b), so that the panel (4, 5) is mounted by the mutual engagement of the resilient projections (25, 26) and recesses (27, 28). The IC-card of claim 1, characterized in that the panel (4, 5) is shaped as a rectangle or a quadrate, and the resilient projections (25, 26) are provided at two opposite sides of the panel (4, 5), respectively. The IC-card of claim 1, characterized in that the panel (4, 5) is shaped as a rectangle or a quadrate, and the resilient projections (25, 26) are provided at all four sides of the panel (4, 5), respectively. The IC-card of claim 2, characterized in that the panel (4, 5) is a rectangle having two opposite long sides (21, 22) and two opposite short sides (23, 24), and the resilient projections (25, 26) are respectively provided in pairs at each of the two opposite long sides (21, 22). The IC-card of any of claims 1 to 4, characterized in that the frame (2) has two openings (8) which are respectively formed in the top and the bottom surface thereof, in that the card has two panels (4, 5), one of which covers the one opening (8) and the other of which covers the other opening (8), and in that the two panels (4, 5) have the same construction but are mounted in the frame (2) in a posture reverse to each other, wherein in each of the panels (4, 5) a distance (L1) between a short side (23, 24) and each of the one resilient projections (25, 26) disposed at one side of individual long sides (21, 22) is different from the distance (L2) between the other short side and each of the other resilient projections (25, 26) disposed at the other end side of the individual long sides (21, 22), in order to prevent the resilient projections (25) of the one panel (4) and the resilient projections (26) of the other panel (5) from interfering with each other. The IC-card of any of claims 1 to 5, characterized by an adhesive material (15) disposed on the back surface of the panel (4, 5), the panel (4, 5) being glued to the frame (2) by means of the adhesive material (15). The IC-card of any of claims 1 to 6, characterized in that the electronic parts (6) are installed in the frame (2) by means of a wiring board (3), and a plurality of electrodes are provided on an end surface of the frame (2), wherein the electrodes are electrically connected with the electronic parts (6) through the wiring board (3). The IC-card of any of claims 1 to 7, characterized in that the panel (4, 5) is made of metal, while the frame (2) is made of resin.

Inventors: OHBUCHI JUN C O MITSUBISHI DEN, UENAKA TAKESHI C O RYODEN KASE, OHBUCHI, JUN C/O MITSUBISHI DENKI K.K., UENAKA, TAKESHI C/O RYODEN KASEI CO. LTD.
Applicants: MITSUBISHI ELECTRIC CORP, MITSUBISHI DENKI KABUSHIKI KAISHA
Application year: 1990
Main classification: G06K19
IPC codes: B42D15, G06K19