WO2019108530A1

WO2019108530A1 - Card socket

Info

Publication number: WO2019108530A1
Application number: PCT/US2018/062594
Authority: WO
Inventors: In Chull Yang; Da Woon Lee
Original assignee: Molex, Llc
Priority date: 2017-11-28
Filing date: 2018-11-27
Publication date: 2019-06-06
Also published as: KR20190061889A; KR102424498B1

Abstract

The present disclosure relates to a card socket for preventing damage to a terminal due to an erroneous insertion by guiding a tray receiving a card to be inserted into a socket housing in a normal direction, in which the card socket comprises: a metal shell comprising a first cover portion at one side with respect to both sides in a card insertion direction, and a second cover portion at the other side, wherein a leading end of the first cover portion and a leading end of the second cover portion form a stepped structure having different positions in the card insertion direction, and wherein the metal shell has a first guide protrusion protruded by bending a region forming the stepped structure downward; and a card tray forming a guide groove of which a top face is recessed in the card insertion direction, wherein the guide groove corresponds to the first guide protrusion, and wherein when the first guide protrusion is inserted into the guide groove, the card tray is inserted into an insertion space at a lower side of the metal shell.

Description

CARD SOCKET

RELATED APPLICATIONS

[0001] This application claims priority to Korean Application No. 10-2017-0160724, filed November 28, 2017, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] Embodiments of the present disclosure are related to a card socket for an electronic device, and more particularly, to a card socket for preventing damage to a terminal due to an erroneous insertion by guiding a tray receiving a card to be inserted into a socket housing in a normal direction.

BACKGROUND ART

[0003] Mobile devices such as smart phones, which have become popular in recent years, commonly make it possible to insert or withdraw a memory card for storing data or a SIM (Subscriber Identification Module) card including subscriber identification information, or the like into/from the devices. To this end, an electronic device is essentially provided with a card socket for mounting a card. Recently, the electronic device is designed to simultaneously mount a plurality of cards on one card socket.

[0004] FIG. I is an exploded perspective view illustrating a main configuration of a card socket according to the related art, and FIG. 2 is an enlarged sectional view illustrating a main part of FIG. 1.

[0005] As illustrated, the card socket may include a housing 10 for receiving a plurality of terminals 11, a metal shell 20 for covering an upper part of the housing while securing a space in which the card is inserted between the housing 10 and the metal shell 20, and a card tray 30 for seating the card 1 to be inserted into and withdrawn from the space. The card socket may be configured such that a number of cards having different functions, such as a memory card or a SIM card, or the like are simultaneously inserted.

[0006] For this purpose, the card tray 30 may have a first card seating portion 3 la on one side where a first card la is seated, and a second card seating portion 31b on the other side where a second card lb is seated. Further, the housing 10 may receive a plurality of first connection terminals 1 la to which the first card la is connected at one side and may receive a plurality of second connection terminals l ib to which the second card lb is connected at the other side.

[0007] In the card socket having the above-described configuration, the card tray 30 should be inserted in parallel in a normal direction from the front face of the card insertion space. In other words, the first card la should be inserted in parallel at the side of the first connection terminal 11a, and the second card lb should be inserted in parallel at the side of the second connection terminal 1 lb.

[0008] The first card la and the second card lb may have different connection structures, and the corresponding first connection terminal I I a and second connection terminal I lb may vary in a size, a position or the like. Therefore, when the first card la is inserted into the side of the second connection terminal 1 lb or the second card lb is inserted into the side of the first connection terminal 11 a, the card tray 30 may deform or damage the connection terminal 1 1, or the connection terminal 11 and the card 1 may be erroneously connected to each other, thereby causing damage to the card or the electronic device.

[0009] In order to avoid this, the metal shell 20 may be provided with a protrusion 22 for preventing the card tray 30 from being inserted in a reverse direction or an oblique direction, and the card tray 30 may be provided with a guide groove 32 of which the insertion direction is guided by the protrusion 22. Since the protrusion 22 is not inserted into the guide groove 32 when the card tray 30 is inserted in the reverse direction or the oblique direction, the card socket may prevent the card tray 30 from being erroneously inserted.

[0010] In the conventional card socket, the protrusion 22 may be formed by cutting a portion of the top face of the metal shell 20 into a 'C shape, and then bending the cut portion downward again. In this case, the reverse insertion of the card tray 30 may be efficiently prevented by the protrusion 22. However, when the card tray 30 is inserted in the oblique direction, there is a problem that the deformation of the protrusion 22 may be caused by an insertion force applied to the protrusion 22.

[0011] In particular, as illustrated in FIG. 2, when the card tray 20 is inserted in the bending direction of the protrusion 22 and a leading end impacts with the protrusion 22 while a. strong external force is applied, the protrusion 22 may easily be deformed in a direction parallel to a direction before it is bent. In addition, the deformed protrusion 22 may not further guide the card tray 30 in a normal direction, but rather may guide the card tray 30 in an erroneous direction, thereby deteriorating the damage to the connection terminal 1 1 or causing an erroneous connection between the card 1 and the connection terminal 11.

[0012] Examples of the related art include Korean Patent Publication Laid-Open No. 10- 2014-0143723, entitled "Card Connector and Card Connector Assembly" (published on December 17, 2014)

SUMMARY

[0013] Therefore, in order to address the above-mentioned problems, it is an objective of the present disclosure to provide a card socket on which a number of cards are mounted, which can prevent a card tray from being inserted in a reverse direction and an oblique direction.

[0014] In particular, it is an objective of the present disclosure to provide a card socket, which can stably protect a terminal by preventing a guide protrusion to avoid the insertion from being deformed even when the card tray is inserted in an oblique direction.

[0015] In order to achieve such objectives, a card socket according to an embodiment of the present disclosure may comprise: a metal shell comprising a first cover portion at one side with respect to both sides in a card insertion direction, and a second cover portion at the other side, wherein a leading end of the first cover portion and a leading end of the second cover portion form a stepped structure having different positions in the card insertion direction, and wherein the metal shell has a first guide protrusion protruded by bending a region forming the stepped structure downward; and a card tray forming a guide groove of which a top face is recessed in the card insertion direction, wherein the guide groove corresponds to the first guide protrusion, and wherein when the first guide protrusion is inserted into the guide groove, the card tray is inserted into an inserti on space at a lower side of the metal shell.

[0016] In addition, the first guide protrusion may comprise a first bending portion in which a portion of the leading end of the first cover portion is bent, and a second bending portion in which a side portion of the leading end of the second cover portion being protruded forward is bent, and further comprise a flat plate portion connecting a lower end of the first bending portion with a lower end of the second bending portion, wherein one side ends of the first bending portion and the second bending portion are connected to each other.

[0017] Further, the metal shell may further comprise a second guide protrusion protruded downward at a position spaced rearward from the first guide protrusion and inserted into the guide groove.

[0018] A card socket according to another embodiment of the present disclosure may comprise: a metal shell comprising a first cover portion at one side with respect to both sides in a card insertion direction, and a second cover portion at the other side, wherein a leading end of the first cover portion and a leading end of the second cover portion form a stepped structure having different positions in the card insertion direction, and wherein the metal shell has a first guide protrusion protruded by bending a region forming the stepped structure downward; a connection terminal array comprising a first connection terminal disposed in a lower space of the first cover portion and a second connection terminal disposed in a lower space of the second cover portion; and a card tray having a guide groove corresponding to the first guide protrusion, and receiving a first card and a second card, wherein the card tray is inserted into a lower space of the metal shell to connect the first card and the second card to the first connection terminal and the second connection terminal.

[0019] In addition, the second connection terminal may be disposed at a front side of the second cover portion and a tip end of the first guide protrusion may be directed toward the first cover portion, so as to prevent the card tray from being inserted in an oblique direction fro the first cover portion to the second cover portion.

[0020] Further, the second connection terminal may be disposed in a direction being inclined with respect to the insertion direction of the card tray.

[0021] In accordance with an aspect of the present disclosure, since the first guide protrusion for preventing an erroneous insertion is not deformed, it can efficiently prevent the card tray from being inserted in a reverse direction and an oblique direction and stably protect the connection terminal.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is an exploded perspective view illustrating a main configuration of a card socket according to the related art;

[0023] FIG. 2 is an enlarged sectional view illustrating a main part of FIG. 1;

[0024] FIG. 3 is a perspective view illustrating an assembled card socket according to an embodiment of the present disclosure,

[0025] FIG. 4 is an exploded perspective view illustrating the card socket of FIG. 3;

[0026] FIG. 5 is a perspective view illustrating a metal shell according to an embodiment of the present disclosure;

[0027] FIG. 6 is an enlarged sectional view illustrating a main part of FIG. 5;

[0028] FIG. 7 is a perspective view illustrating an example of a process for inserting a card tray;

[0029] FIG. 8 is a perspective view illustrating another example of a process for inserting a card tray;

[0030] FIGS. 9A and FIG. 9B are plan views illustrating examples in which the card tray is erroneously inserted; and

[0031] FIG. 10 is a perspective view illustrating a metal shell according to another embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] A variety of aspects of the present disclosure and technical objectives to be achieved according to those aspects of the present disclosure will be more apparent from preferred embodiments as set forth below. In the following description of the present disclosure, the expression such as "first," "second," and the like is intended for the convenience of distinguishing a number of same or similar elements, and the technical meaning thereof is not necessarily bound to a dictionary definition. Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings.

[0033] FIG. 3 is a perspective view illustrating an assembled card socket according to an embodiment of the present disclosure, and FIG. 4 is an exploded perspective view illustrating the card socket according to an embodiment of the present disclosure.

[0034] As illustrated in these figures, the card socket according to an embodiment of the present disclosure may be configured such that a number of cards l having the same or different functions, such as a memory card or a SIM card, are mounted on an electronic device such as a smart phone. The card socket may include a housing 100 in which a connection terminal 110 is formed for being connected to a card 1, a metal shell 200 coupled to a top face of the housing 100 while covering the top face of the housing 100, and a card tray 300 for inserting and withdrawing the card 1 into/from a card insertion space formed between the housing 100 and the metal shell 200. The card socket may be provided at one side of the electronic device and may be configured to make it possible to simultaneously insert and withdraw a first card, a second card, and a third card, in accordance with an embodiment of the present disclosure. For example, the first card may be a memory card, and the second card and the third card may be SIM cards.

[0035] Specifically, the housing 100 may be configured to guide the position of the connection terminal 1 10 for connecting the card while receiving the connection terminal 110, and may be made of a molded body using an insulating material The housing 100 may be fixed to a printed circuit board 2 and may expose the connection terminal 110, which is mounted on the board 2 through a through hole 120, to the card insertion space at the upper side thereof. In addition, the housing 100 may include a first housing 100a for receiving a first connection terminal 1 10a, a second housing 100b for receiving a second connection terminal 1 10b, and a third housing 100c for receiving a third connection terminal 110c. The first to third housings 100a, 100b, 100c may be made of individual molded bodies separated from each other, or may be made of one molded body integrally connected to each other.

[0036] When the first to third cards la, lb, lc are inserted through the card tray 300, the first to third connection terminals 1 10a, 110b, 1 10c may be connected to the respective cards. A resilient contact portion of each connection terminal 110 may be exposed to the upper part of the housing 100 while forming a curved surface shape with each connection terminal 110 being mounted on the board 2. In particular, the connection terminal 110 may be mounted in parallel with the card insertion direction (tray insertion direction) in the longitudinal direction, such as the first connection terminal 110a. However, in general, taking into consideration the reliability of contact, the connection terminal 1 10 may be mounted while being inclined in the left or right direction with respect to the card insertion direction, such as the second connection terminal 110b and the third connection terminal 110c. Further, the second connection terminal 110b may be mounted to be located at the front side of the card insertion space, and the third connection terminal 110c may be mounted to be located at the rear side of the card insertion space (i.e., the rear side of the second connection terminal). As used herein, the position where the insertion of the card tray is started is referred to as the 'front side’, and the relative position where the insertion is terminated is referred to as the 'rear side.

[0037] Furthermore, the rear side of the housing 100 may he provided with an ejecting bar 130 for controlling the insertion and withdrawal of the card tray 300.

[0038] The metal shell 200 may be coupled to the upper part of the housing 100 and may function as a socket cover for protecting the connection terminal 110 and the card 1. The metal shell 200 may be formed by extrusion molding a plate made of a metal material. In addition, the metal shell 200 may include a cover portion 210 in which a space for inserting the card is formed by securing a gap between the housing 100 and the metal shell 200, and a coupling portion 220 in which both sides of the cover portion 210 are bent for being mounted on the board 2.

[0039] The cover portion 210 may include a first cover portion 2I0a on one side and a second cover portion 210b on the other side, with respect to both sides in the direction where the card tray 300 is inserted or withdrawn. The first cover portion 210a may cover the upper part of the first housing 100a, while protecting the first connection terminal 1 10a and the first card la. The second cover portion 210b may cover the upper parts of the second housing 100b and the third housing 100c, while protecting the second connection terminal 110b, the third connection terminal 1 10c, the second card lb, and the third card lc.

[0040] The leading end 210a' of the first cover portion 210a may form a step (t) having different positions in the front and rear directions than the leading end 210b' of the second cover portion 210b. In other words, as illustrated, the leading end 21 Qa' of the first cover portion 210a may be recessed rearward relative to the leading end 2101V of the second cover portion 210b, or the leading end 210b' of the second cover portion 210b may be protruded forward relative to the leading end 210a' of the first cover portion 210a. The leading end 210a' of the first cover portion 210a and the leading end 210b' of the second cover portion 210b may be connected to each other through a first guide protrusion 230.

[0041] The first guide protrusion 230 may be configured to prevent the card tray 300 from being inserted in a reverse direction and an oblique direction, and the first guide protrusion 230 may be formed by being protruded downward at a connection portion forming a stepped structure between the first cover portion 210a and the second cover portion 210b.

[0042] The card tray 300 may have a number of cards 1 seated thereon and may connect the card 1 to the connection terminal 1 10 by being inserted into the insertion space of the housing 100 or may disconnect them by being withdrawn from the insertion space. The card tray 300 may be made of an injection molded material using a plastic resin and may include a card seating portion 310 for seating the card 1, and a handle portion 320 for the insertion and withdrawal.

[0043] The card seating portion 310 may include a first card seating portion 310a for seating the first card la, in which the first card seating portion 310a is formed on one side of both sides in the direction where the card tray 300 is inserted, and a second card seating portion 310b and a third card seating portion 310c for seating the second card lb and the third card lc, respectively, in which the second card seating portion 310b and the third card seating portion 310c are formed on the other side. Further, a slot-shaped guide groove 330 may be formed at the center of the card seating portion 310 along the front and rear directions in the card tray 300. The first guide protrusion 230 of the metal shell 200 may be inserted into the guide groove 330, thereby guiding the card tray 300 to be inserted and withdrawn in a normal direction

[0044] FIG. 5 is a perspective view illustrating a metal shell according to an embodiment of the present disclosure; FIG. 6 is an enlarged sectional view' illustrating a main part of FIG. 5; and FIGS. 7 and 8 are perspective view's illustrating a process of inserting the card tray.

[0045] Referring to FIGS. 5 and 6, the metal shell 200 according to an embodiment of the present disclosure may include a cover portion 210 for providing a space in which the card tray- 300 is inserted, and the cover portion 210 may include a first cover portion 210a and a second cover portion 210b. The leading end 210a’ of the first cover portion 210a may be recessed rearward while forming a step (t) with the leading end 210b' of the second cover portion 210b. In this case, a first guide protrusion 230 protruding toward the direction of the lower card insertion space may be formed in a stepped region where the leading end 210a' of the first cover portion 210a and the leading end 210b' of the second cover portion 210b are connected to each other. The first guide protrusion 230 may include a portion of the leading end 210a' of the first cover portion 210a and a side portion of the leading end 21 Ob' of the second cover portion 210b.

[0046] Specifically, the first guide protrusion 230 may include a first bending portion 231 in which a portion of the leading end 210a' of the first cover portion 210a is bent downward, a second bending portion 232 in which a side portion of the leading end 210b' of the second cover portion 210b is bent downward, and a flat plate portion 233 connecting the lower ends of the first bending portion 231 and the second bending portion 232. The first guide protrusion 230 having the above-described structure may be formed by pressing a stepped portion where the first cover portion 210a and the second cover portion 210b are connected in the cover portion 210 of a plate shape.

[0047] The first bending portion 231 may be formed in a width direction (a direction perpendicular to a direction in which the card tray is inserted), and the second bending portion 232 may be formed in the front and rear directions (a direction in which the card tray is inserted). Further, the first bending portion 231 and the second bending portion 232 may form a ' n ' shape while one side ends thereof are connected to each other. The flat plate portion 233 may connect the lower end of the first bending portion 231 with the lower end of the second bending portion 232.

[0048] Therefore, since the first bending portion 231 and the second bending portion 232 are mutually supported at a connected edge portion, resistance to an external force can be enhanced such that deformation due to the external force does not occur. In addition, since the lower ends of the first bending portion 231 and the second bending portion 232 are connected to each other and supported by the flat plate portion 233, they may have more resistance to an external force.

[0049] Referring to FIG. 7, according to the card socket having such a configuration, since the first guide protrusion 230 is inserted along the guide groove 330 when the card tray 300 is inserted in a normal direction, the card tray 300 can be easily inserted. However, when the card tray 300 is inserted in an oblique direction, the first guide protrusion 230 may not be inserted into the guide groove 330 and may impact with the leading end 300’ of the card tray 300. In this case, even if the card tray 300 impacts with the first guide protrusion 230 by a forced external force, since the first bending portion 231, the second bending portion 232, and the flat plate portion 233 are connected to each other and reinforced, it can efficiently prevent the card tray 300 from being inserted in an oblique direction without causing deformation.

[0050] Referring back to FIG. 5, the metal shell 200 according to an embodiment of the present disclosure may further include a second guide protrusion 240 for guiding the card tray 300 to be inserted in a normal direction. The second guide protrusion 240 may be formed by being protruded downward at a rear side spaced apart from the first guide protrusion 230 by a predetermined distance.

[0051] The second guide protrusion 240 may guide the card tray 300 so that the insertion direction of the card tray 300 is not deflected during the process of inserting the card tray 300. In other words, when the card tray 300 is inserted in a normal direction, the first guide protrusion 230 may be inserted along the guide groove 330, and then the second guide protrusion 240 may be inserted along the guide groove 330, thereby making it possible to retain the insertion of the normal direction until the insertion is completed.

[0052] Further, the second guide protrusion 240 can prevent the card tray having a single structure from being erroneously inserted, thereby protecting the connection terminal 110. While it is generally preferable that the card tray having a dual structure in a width direction is inserted into the card socket according to an embodiment of the present disclosure, the card tray having a single structure may be inserted due to a user's mistake or the like. The single card tray 400 may be inserted into the insertion space formed by the first housing 100a and the first cover portion 210a, while the memory card is only seated therein

[0053] As illustrated in FIG. 8, the single card tray 400 may be inserted in an oblique direction with the first guide protrusion 230 being avoided or with the first guide protrusion 230 being arbitrarily removed by the user. In such a case, the second guide protrusion 240 may impact with the leading end 400' of the single card tray 400 being inserted without being blocked by the first guide protrusion 230, thereby preventing the single card tray 400 from being further inserted. Therefore, the second guide protrusion 240 can prevent the single card tray 400 from being inserted in an oblique direction, thereby protecting the second connection terminal 110b and the third connection terminal 110c mounted on the opposite side (i.e., the second cover portion).

[0054] In addition, since the second guide protrusion 240 is located at the center region of the cover portion 210, which is the rear position of the first guide protrusion 230, the second guide protrusion 240 cannot arbitrarily be removed by the user, and therefore, an erroneous insertion can be efficiently further prevented.

[0055] FIGS. 9A and 9B are plan views illustrating examples in which the card tray is erroneously inserted. FIG. 9A illustrates an example in which the card tray is erroneously inserted in an oblique direction directing from the left side to the right side, and FIG. 9B illustrates an example in which the card tray is erroneously inserted in an oblique direction directing from the right side to the left side.

[0056] The card socket according to an embodiment of the present disclosure may have a structure, in which the first connection terminal 110a is received in the first housing 100a on the left side, the second connection terminal 1 1 Oh is received in the second housing 100b on the right front side, and the third connection terminal 110c is received in the third housing 100c on the right rear side. In addition, the metal shell 200 may form a step (t), in which the leading end 210a' of the first cover portion 210a for protecting the first connection terminal 110a is recessed backward, and the leading end 21 Ob' of the second cover portion 210b for protecting the second connection terminal 110b and the third connection terminal 110c is protruded forward. Further, the second connection terminal 210b and the third connection terminal 210c may be di sposed in an oblique direction of the left or right side with respect to the card insertion direction.

[0057] Referring to FIG. 9A, when the card tray 300 is inserted into the card socket while being inclined in a direction from the left side to the right side, the leading end 300' of the card tray 300 may impact with the tip end (see 230' in FIG. 6) of the first guide protrusion 230 to be blocked, so that it cannot be further inserted while being spaced apart from the second connection terminal 110b by a predetermined distance L, thereby protecting the second connection terminal 1 10b. In particular, since the terminal side of the second connection terminal 110b faces the leading end 300' of the card tray 300, it may cause serious damage when it impacts with the card tray 300. However, the tip end 230' of the first guide protrusion 230 can block the leading end 300' of the card tray 300, thereby preventing the insertion even if an external force is continuously applied to the card tray 300, and protecting the second connection terminal 110b.

[0058] In addition, referring to FIG. 9B, when the card tray 300 is inserted into the card socket while being inclined in a direction from the right side to the left side, the leading end 300' of the card tray 300 may impact with the bending end (see 230" in FIG. 6) of the first guide protrusion 230 to be blocked. In other words, even if the card tray 300 is erroneously inserted while being inclined in a direction from the right side to the left side, the insertion can be blocked.

[0059] However, since the bending end 230" of the first guide protrusion 230 has a curved surface shape, it does not have a strong blocking force, and therefore, the card tray 300 may be forcedly inserted when an external force is continuously applied to the card tray 300. In such a case, since the second connection terminal 110b is inclined in a direction parallel with or similar to the insertion direction of the card tray 300, the card tray 300 may be inserted while being contacted along the curved portion of the second connection terminal 1 10b, and accordingly, the second connection terminal 110b may not be damaged or the damage may be minimized. Then, even if the card tray 300 is forcedly inserted by passing through the first guide protrusion 230, the second guide protrusion 240 can prevent the card tray 300 from being further inserted, thereby protecting the first connection terminal 110a.

[0060] Therefore, the metal shell 200 according to an embodiment of the present disclosure can efficiently protect the connection terminal 110 by selecting the corresponding direction of the first guide protrusion 230 depending on an oblique direction of the connection terminal to be protected. That is, the leading end of the metal shell 200 may be configured to have a stepped structure in which the cover portion 210 for protecting the connection terminal 110 located at a relatively front side is relatively protruded, and to form the first guide protrusion 230 being protruded and bent downward between the leading ends of the adjacent cover portions.

[0061] FIG. 10 is a perspective view illustrating a metal shell according to another embodiment of the present disclosure.

[0062] In the metal shell 200 according to another embodiment of the present disclosure, the first guide protrusion 230 may be formed such that the leading end 2I0a' of the first cover portion 210a and the side portion of the leading end 210b' of the second cover portion 210b are bent downward, and a tip end 230' may be protruded to be directed downward. Specifically, the first guide protrusion 230 may include a first bending portion 231 in which a portion of the leading end 210a' of the first cover portion 210a is bent downward, and a second bending portion 232 in which the side portion of the leading end 21 Ob’ of the second cover portion 210b is bent downward.

[0063] Since the first guide protrusion 230 having such a structure has the tip end 230’ directed downward, the insertion of the card tray 300 can be blocked by the same blocking force with respect to the card tray 300 inserted in the oblique directions at both of the left and right sides. In other words, since the tip end 230' of the first guide protrusion 230 is directed downward, the blocking force can be uniformly dispersed into both sides, thereby relatively improving the blocking force with respect to the card tray 300 inserted in the oblique direction from the right side to the left side.

[0064] While the present disclosure has been particularly described with reference to exemplary embodiments thereof, it is to be understood that a variety of modifications and other equivalent embodiments can be made by a person skilled in the art from the disclosed embodiments.

Claims

CLAIMS What is claimed is:

1. A card socket, comprising:

a metal shell compri sing a first cover portion at one side with respect to both sides in a card insertion direction, and a second cover portion at the other side, wherein a leading end of the first cover portion and a leading end of the second cover portion form a stepped structure having different positions in the card insertion direction, and wherein the metal shell has a first guide protrusion protruded by bending a region forming the stepped structure downward; and a card tray forming a guide groove of which a top face is recessed in the card insertion direction, wherein the guide groove corresponds to the first guide protrusion, and

wherein when the first guide protrusion is inserted into the guide groove, the card tray is inserted into an insertion space at a lower side of the metal shell.

2. The card socket of claim 1, wherein the first guide protrusion comprises: a fi rst bending portion in which a portion of the leading end of the first cover portion is bent; and

a second bending portion in which a side portion of the leading end of the second cover portion being protruded forward is bent.

3. The card socket of claim 2, wherein the first guide protrusion is configured such that one side ends of the first bending portion and the second bending portion are connected to each other

4. The card socket of claim 3, wherein the first guide protrusion further comprises:

a flat plate portion connecting the lower end of the first bending portion with the lower end of the second bending portion

5. The card socket of claim 1, wherein the metal shell further comprises:

a second guide protrusion protruded downward at a position spaced rearward from the first guide protrusion and inserted into the guide groove.

6. A card socket, comprising;

a metal shell comprising a first cover portion at one side with respect to both sides in a card insertion direction, and a second cover portion at the other side, wherein a leading end of the first cover portion and a leading end of the second cover portion form a stepped structure having different positions in the card insertion direction, and wherein the metal shell has a first guide protrusion protruded by bending a region forming the stepped structure downward; a connection terminal array comprising a first connection terminal disposed in a lower space of the first cover portion and a second connection terminal disposed in a lower space of the second cover portion; and

a card tray having a guide groove corresponding to the first guide protrusion, and receiving a first card and a second card, wherein the card tray is inserted into a iow-er space of the metal shell to connect the first card and the second card to the first connection terminal and the second connection terminal.

7. The card socket of claim 6, wdierein the second connection terminal is disposed at a front side of the second cover portion, and a tip end of the first guide protrusion is directed toward the first cover portion, so as to prevent the card tray from being inserted in an oblique direction from the first cover portion to the second cover portion.

8. The card socket of claim 7, wherein the second connection terminal is disposed in a direction being inclined with respect to the insertion direction of the card tray.