Card-shaped electronic device

Abstract: A rectangular flat box-like main body of the card-shaped electronic device can be inserted into and taken out of an electronic apparatus in a given insertion direction. The main body has a pair of lateral sides extending in the insertion direction. A pair of shield plates (154) are fixed to the main body to cover the upper and lower surfaces of the main body. Each shield plate is formed of a metal and includes a bent portion which is fitted on a lateral side of the main body and constitutes a conductive portion (160) for conducting the shield plates with the electronic apparatus when the main body is loaded in the electronic apparatus.

Description: The present invention relates to a card-shaped electronic device to be used with an electronic apparatus. Such a card-shaped electronic device is known from document WO-A-91/00681. Some of laptop personal computers can incorporate card-type or card-shaped electronic components, such as memory cards, modem cards, etc., which are adapted to be laterally inserted into the computer body, in order to expand their functions. Generally, in the computers of this type, a card inlet slot is formed in a side face of the body, and a card storing section is formed in the body so as to communicate with the inlet slot. A card can be incorporated into the computer body by being inserted into the card storing section through the inlet slot. With the progress of semiconductor technology, various card-type electronic components which are in conformity to the standards provided by, e.g., JEIDA (Japanese Electric Industry Development Association) have recently been developed and spread. The card-type electronic components include various cards, such as modem cards, which handle high-frequency signals. These components must be fully shielded. In conventional card-type electronic components, which are represented by memory cards, for example, grounding terminals are arranged only in an interface connector to be connected to the computer body. In this case, the ground contact area cannot be wide enough for satisfactorily antijamming. Accordingly, it has been proposed that one such card-type electronic component should be designed so that flat shielding plates are arranged individually on the upper and lower surfaces of a card body, and are connected electrically to grounding contact pieces on the computer body to be loaded with the electronic component. When the electronic component is loaded into a card storing section of the computer body, the shielding plates are brought individually into direct contact with the grounding contact pieces, which are arranged above and below in the card storing section. However, the above-described arrangement involves the following problems. In the standardized card-type electronic components, the thickness of the card body is prescribed only with respect to its maximum value (e.g., 5.0 mm in the case of the standards Type II provided by JEIDA), so that it varies depending on the types of components, manufacturers, etc. In some of various kinds of cards, those portions which are to be in contact with the grounding contact pieces in the card holding section of the computer body are extremely different in thickness. In alternatively loading these various cards into the same card storing section, in particular, the following problems are aroused. If a relatively thin card is used after prolonged use of a thicker card of which the thickness of the portions to be in contact with the grounding contact pieces in the card holding section is substantially equal to the prescribed maximum dimension, or if thick and thin cards are repeatedly used by turns, the grounding contact pieces fail to enjoy satisfactory contact with the shielding plates of the card, thus bringing about a noncontact or unstable contact state, due to reduction of the spring pressure of the grounding contact pieces. In such a case, the shielding effect of the card is ruined completely, or noises are liable to be produced due to unstable contact. In loading into or unloading the card-type component from the card storing section, in the arrangement described above, moreover, the grounding contact pieces in the holding section slide individually on the upper and lower shielding plates of the card. As the contact pieces slide in this manner, the shielding plates and/or the contact pieces are shaven away to produce metallic powder. This metallic powder may possibly enter the computer body and cause wrong operation of the computer. In general, moreover, the upper and lower shielding plates of the card-type component are each in the form of a design plate bearing a coating, patterns, etc. for improved design properties, except for those conduction portions thereof which are brought into contact with the grounding contact pieces when the component is set in a predetermined position in the card storing section. When the card-type component is loaded into or unloaded from the card storing section, as mentioned before, however, design portions of the shielding plates are also brought into sliding contact with the grounding contact piece, so that removal of the coating or the like is caused. Since neither coating nor patterns are put on the conduction portions, moreover, the design properties of the card-type component may possibly be lowered. In view of these circumstances, it is therefore an object of the present invention to provide a card-shaped electronic device used with an electronic apparatus, which can be securely shielded and protected against any adhesion of harmful metal particles and damages that may be brought forth on the surface of the device when it is moved into or away from the electronic apparatus. According to the present invention, the above object is achieved by providing a card shaped electronic device as defined in claim 1. Preferred embodiments are defined in the sub-claims. This device specifically comprises: a rectangular flat box-like mainbody to be inserted into and taken out of the portable electronic apparatus in a given insertion direction, the main-body having a pair of lateral sides extending in the insertion direction; a pair of shield plates fixed to the main-body to cover the upper and lower surfaces of the main-body; and a conductive portion arranged on the lateral side of the main-body and electrically connected to the shield plates, for conducting the shield plates with the electronic apparatus when the main-body is loaded in the electronic apparatus. In a card-shaped electronic device having a configuration as described above, since the conductive section of the device for electrically connecting the shield plates to an electronic apparatus is arranged along the lateral sides of the body, the shield plates are not touched nor abraded by the related contact terminals of the apparatus in which the card-shaped device is mounted. Therefore, generation of fine metal particles due to abrasion of the shield plates is nonexistent. If the shield plates are decorated, the decoration may not be damaged nor removed because no abrasion takes place there. Even if a card-shaped electronic device is used with card main-bodies having different heights, the conductive section ensures a secure electric connection between the device and the related contact terminals of the portable electronic equipment in which the device is mounted and a reliable shield effect is provided by the shield plates. This invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which: Figs. 1 through 23 show an embodiment of a personal computer and a card-shaped electronic device according to the present invention, in which: Fig. 1 is a perspective view of the personal computer and the card shaped electronic device shown separately; Fig. 2 is an exploded perspektive view of the embodiment whose display cover is taken away; Fig. 3 is an enlarged perspective view of an arrangement around a fluorescent lamp used as a back light for the display of the embodiment; Fig. 4 is an exploded perspective view of arrangement around the fluorescent lamp of Fig. 3; Fig. 5 is a sectional view of the arrangement around the fluorescent lamp of Fig. 3 taken along line A-A; Fig. 6 is an enlarged perspective view of a latch mechanism used for locking and unlocking the display; Fig. 7 is an exploded perspective view of the latch mechanism; Fig. 8 is a sectional view of the latch mechanism of Fig. 6 taken along line B-B; Fig. 9 is a sectional view of the latch mechanism of Fig. 6 taken along line C-C; Fig. 10 is a perspective view of the computer of Fig. 1 showing its bottom side; Fig. 11 is an exploded perspective view of the computer of Fig. 1 whose lower case is removed; Fig. 12 is an exploded perspective view of the computer of Fig. 1 whose components fitted to its upper case are moved away to show only the components disposed between an insulation sheet and the lower case; Fig. 13 is an exploded perspective view of the computer of Fig. 1 showing the components disposed between the upper case and the insulation sheet; Fig. 14A is a sectional view viewed along arrow D in Fig. 11; Fig. 14B is a partially broken front view of the computer; Fig. 15 is a perspective view of a memory card; Fig. 16 is an exploded perspective view of the memory card; Fig. 17 is an enlarged and exploded perspective view of a conductive section of the memory card; Fig. 18 is a perspective view of an interface card; Fig. 19 is a perspective view of a card ejector mechanism; Fig. 20 is an exploded perspective view of the card ejector mechanism; Fig. 21 is a perspective view of the card ejector mechanism with a card inserted therein; Fig. 22 is a perspective view of the card ejector mechanism whose drawer member is pulled out; Fig. 23 is a perspective view of the card ejection mechanism under a condition where the rear end of a card is pulled out of the main body of the computer as the card mount of a card receiver is moved from its proper position; Fig. 24 is a perspective view of an interface card according to a modification of the embodiment of the invention; Fig. 25 is a perspective view of an interface card according to another modification of the embodiment of the invention; and Fig. 26 is a perspective view of an interface card according to a still further modification of the embodiment of the invention. Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Figs. 1 and 23 show an embodiment in which a portable electronic apparatus according to the present invention is applied to a laptop personal computer by way of example. As shown in Fig. 1, the computer comprises a body 1 in the form of a flat box and a flat display 2. The body 1 is a combination of upper and lower plastic cases 1a and 1b which are plated inside (not shown) for shielding. The display 2 is swingably mounted on a stepped portion 1c, which is formed at the rear portion of the top face of the body 1, by means of a pair of legs 3. A keyboard 60 is arranged on the front portion of the top face of the body 1. The construction of the display 2 is illustrated in Figs. 1 to 9. The display 2 has a very thin, rectangular body 10, which includes a plastic bottom case 11 in the form of a flat box and a plastic cover 12 in the form of a rectangular frame and fixed to an opening portion of the bottom case. Both the bottom case 11 and the cover 12 are plated inside (not shown) for shielding. An opening portion 12b of the cover 12 is biased a little to the right. A peripheral edge portion of the cover 12, which extends continuously from the middle of each side edge portion to the upper edge portion of the cover, projects forward, and constitutes a U-shaped stepped portion 12a. Two-piece divided casing halves 13a and 13b, which constitute each leg 3, protrude from each side of the respective lower portions of the bottom case 11 and the cover 12. Hinge members (not shown), which are contained individually in the legs 3, are connected to supporting portions 14 (shown in Fig. 13 only), which are arranged inside the stepped portion 1c of the body 1, thereby supporting the display 2 for swinging motion. In Fig. 13, numeral 15 denotes a connecting piece of each hinge member. A display device 16 with a back-light is contained in the body 10 of the display 2. As shown in Fig. 4, the display device 16 includes a display unit 19, a pair of drive units 20, a pair of sockets 23, and a fluorescent lamp 24. The display unit 19 has a liquid crystal display section 17, e.g., in the form of a plate, and a plate-shaped light guide member 18 (shown in Fig. 5 only) put on the rear face of the display section 17. The drive units 20, which are each composed of a circuit substrate 22 mounted with driver circuits 21, are arranged individually in the opposite sides of the display unit 19 with respect to the width direction thereof. The sockets 23 are connected individually to the upper and lower end portions of the right-hand drive unit 20. The fluorescent lamp 24, which is connected between the sockets 23, emits illumination light to the light guide member 18. All these components constitute a panel-shaped main unit 29. A drive unit 25 for the fluorescent lamp 24 is connected to the sockets 23 of the lamp 24 by means of lead wires 26, individually, and is arranged parallel to the right-hand drive unit 20. A pair of connecting frames 27, having a U-shaped cross section, are fitted individually on the respective upper and lower end portions of the display unit 19 and the paired drive units 20, which are arranged side by side in a line, thereby connecting all these units but the drive unit 25. Numeral 28 denotes dial knobs on the drive unit 25, which are used to adjust the light quantity and display density, for example. As shown in Fig. 5, the fluorescent lamp 24 and the light guide member 18 are connected to each other by means of a shielding film 32 which covers them. Thus, the light from the lamp 24 can be guided to the incidence end of the member 18 without leakage. As shown in Figs. 3 and 4, the main unit 29 is mounted on the bottom case 11 so that the display screen of the liquid crystal display section 17 faces the opening portion 12b of the cover 12. More specifically, the unit 29 is mounted on the bottom surface of the bottom case 11 in a manner such that its upper and lower edge portions are fitted individually in a pair of elongated fixing members 30 with an L-shaped cross section, which are screwed to the case 11. In this case, the display unit 19 need not be provided with tapped holes for the fixation to the bottom case 11, and the liquid crystal display section 17 can enjoy a wide display region. Spacers 31 (see Fig. 5) are previously attached to various parts of the rear face of the display unit 19 so that a gap is defined between the rear face of the unit 19 and the bottom surface of the bottom case 11 when the main unit 29 is set on the case 11. The drive unit 25 for the fluorescent lamp 24 is mounted on that portion of the bottom surface of the bottom case 11 which is situated between the lamp 24 and a peripheral wall 11a on the right-hand side of the case 11. The dial knobs 28 are exposed to the outside through a notch 33 which is formed in the wall 11a. In Fig. 2, numeral 35 denotes fixing screws for fixing the various parts. In Fig. 5, numeral 36 denotes insulating sheets arranged on the inner surfaces of the bottom case 11 and the cover 12. A protection rib 34 is provided between the fluorescent lamp 24 and the drive unit 25. More specifically, the rib 34 is formed integrally with the bottom case 11, and protrudes from the bottom surface of the case 11, as shown in Figs. 4 and 5. The rib 34 extends along the lamp 24 in the axial direction thereof so as to cover the overall length of the lamp. The height of projection of the rib 34 is adjusted to a dimension such that the rib projects beyond the respective top positions of the fluorescent lamp 24 (including the shielding film 32), set on the bottom case 11, and the drive unit 25, as shown in Fig. 5. Specifically, the height of the rib 34 is larger than the diameter of the fluorescent lamp 24. In this embodiment, the rib 34 is formed so that its projecting end abuts against the inner surface of the cover 12. The rib 34 serves to protect the fluorescent lamp 24 against an external force, if any, which pushes the face of the cover 12, thereby deforming the cover, or acts in the direction to twist the body 10 of the display 2, for example. The respective walls of the bottom case 11 of the display 2 and the cover 12 are made very thin, e.g., as thin as about 1.5 mm, for reduced size and weight, so that they are easily deformable. If the cover 12, for example, can be bent by a press or twist, therefore, it may possibly interfere with the fluorescent lamp 24, thereby damaging it. Since the rib 34 is set up beside the lamp 24, however, the flexible cover 12 abuts against the distal end portion of the rib 34 before it engages the lamp 24. Thus, the lamp 24 can be protected against contact with the flexible cover 12. Naturally, the rib 12 serves to improve the rigidity of the thin, easily deformable bottom case 11, as well as to protect the lamp 24. Thus, even though the body 10 is thin-walled, necessary rigidity can be secured for the individual parts. A pair of latch devices 40 are arranged individually on the right- and left-hand end sides of the body 10. They are used to lock the display 2 in the position where it covers the keyboard 60, or to unlock the display 2 so that the display can be opened. Conventionally, a latch device inevitably requires use of two hook means for connecting two parts in- and outside the body. According to this embodiment, however, each latch device 40 is designed having only one hook means for firm or unreleasable connection, in order to make the body 10 thinner. Figs. 6 to 9 illustrate the construction of the left-hand latch device 40. This latch device 40 comprises a slide knob 41 which is attached to the peripheral wall 11a of the bottom case 11 of the display 2 so as to be slidable in the direction parallel to the bottom surface of the case 11. The knob 41 is composed of a rectangular operating plate 42 and a fixing hook 43 protruding from the rear face thereof. The hook 43 includes a belt-shaped portion 44 extending parallel to the bottom surface of the bottom case 11 from the rear face of the plate 42. At claw 45 is formed on the distal end portion of the hook 43. The claw 45 has a catch surface 45a which extends in the operating direction (indicated by arrow X in Fig. 6) of the operating plate 42 and faces the peripheral wall 11a. The claw 45 and the belt-shaped portion 44 penetrate a guide hole 46, which is formed in the peripheral wall 11a on the left-hand side of the bottom case 11 so as to extend parallel to the bottom surface of the case 11, and project into the case 11. The length of the hole 46 is greater than the width of the belt-shaped portion 44. Further, the latch device 40 comprises a slider 47 located in the bottom case 11. The slider 47 is in the form of, for example, a tube having a rectangular section. As shown in Fig. 7, the slider 47 is arranged so that one end opening of its bore faces the guide hole 46, and that the lengthwise direction of the one end opening is substantially parallel to the bottom surface of the bottom case 11. A downward latch claw 48 protrudes from the front face of the slider 47 which is directed to the cover 12. Longer and shorter guide rods 49 and 50 protrude from the upper and lower end portions, respectively, of the slider 47, and extend parallel to the peripheral wall 11a of the bottom case 11. The shorter guide rod 50 slidably penetrates a slit 51a of a U-shaped seat 51, which protrudes from that portion of the inner surface of the peripheral wall 11a situated below the lower end of the guide hole 46. The longer guide rod 49 slidably penetrates a slit 52a of a U-shaped seat 52, which protrudes from that portion of the inner surface of the wall 11a situated above the upper end of the hole 46. Thus, the slider 47 is movable between the two seats 51 and 52. The respective openings of the slits 51a and 52a of the seats 51 and 52 are directed to the cover 12 (on the front side) so that the slider 47 can be fitted and removed with ease. A compressed coil spring 53 is wound around the guide rod 49 in a manner such that it is retained between the seat 52 and the upper end portion of the slider 47. The spring 53 urges the slider 47 toward the lower end of the bottom case 11. Formed in the bore of the slider 47 is a projection 54 which can releasably engage the claw 45 of the slide knob 41. The hook 43 is inserted into the bore of the slider 47 through the guide hole 46 in the peripheral wall 11a, and the claw 45 engages the projection 54. The position of the projection 54 is adjusted so that the catch surface 45a of the claw 45 engages the projection 54 when the claw 45 is inserted in the slider 47 in a manner such that the operating plate 42 is in contact with the outer surface of the peripheral wall 11a. Thus, the plate 42 can be positioned in a predetermined position. The overall length of the square bore of the slider 47 (width of the slider 47) is adjusted to a dimension such that the distal end portion of the claw 45 can penetrate the bore. When the claw 45 engages the slider 47, its distal end portion projects sideways from the slider. A vertically elongated hole 55 is formed in that flat portion of the stepped portion 12a of the cover 12 which corresponds in position to the latch claw 48. When the cover 12 is attached to the bottom case 11, the distal end portion of the latch claw 48 projects forward from the cover 12 through the hole 55. A rib 56 for stopping the claw 45 protrudes integrally from that portion of the inner surface of the cover 12 which faces the rear face of the claw 45 projecting sideways from the slider 47. The height of the rib 56 is adjusted to a dimension such that the distal end of the rib is in sliding contact with (or in close vicinity to) the rear face of the claw 45, as shown in Figs. 8 and 9, when the cover 12 is attached to the bottom case 11. The rib 56 continuously extends so as to cover the whole range of the sliding motion of the slide knob 41. Before the cover 12 is attached to the bottom case 11, the knob 41 engages the slider 47 only in an easily releasable manner, that is, the claw 45 is loosely in engagement with the projection 54. When the cover 12 is attached to the case 11, however, the claw 45 is pressed by the rib 56, as shown in Figs. 8 and 9, so that the claw 45 is restrained from moving in the direction to be disengaged from the projection 54. In this manner, the claw 45 is prevented from slipping out of the slider 47. Thus, the two parts in and outside the body 10, that is, the slide knob 41 and the slider 47, are firmly connected by means of the single hook means 43. Square latch holes 57 are formed individually on the opposite sides of the front portion of the upper case 1a of the computer body 1, corresponding in position to the right- and left-hand latch claws 48 which project from the cover 12. When the display 2 is closed, each claw 48 engages its corresponding latch hole 57, so that the display 2 is locked in the closed position. By sliding the operating plate 42 of each slide knob 41 against the urging force of the coil spring 53, each latch claw 48 can be disengaged from its corresponding latch hole 57 to unlock the display 2. Figs. 10 to 14A show the general construction of the body 1 of the personal computer. In this embodiment, the body 1 is constructed so that various devices, circuit boards, etc. are mounted in the upper case 1a which carries the keyboard 60 thereon. More specifically, a rectangular opening 4, through which keys of the keyboard 60 are exposed, is formed in the front portion of the upper surface of the upper case 1a, and a plurality of openings, through which various terminals are exposed, are formed in the rear portion of the peripheral wall of the upper case, as shown in Figs. 13 and 14A. That portion of the upper case 1a which extends along the peripheral edge of the opening 4 is bent backward to form a rib 62, which serves to retain the keyboard 60 set in the opening 4. The rib 62 carries thereon the edge portion of the keyboard 60, on which a large number of keys 63 are arranged. The keys 63 are exposed to the outside through the opening 4. A plurality of claws 62 protrude from the rib 62. The keyboard 60 is located in a predetermined position with these claws 62a in engagement with notches 64 in the peripheral edge portion of the keyboard. In Fig. 13, numeral 70 denotes a connecting terminal which extends from the keyboard 60. The keyboard 60 has a substrate 65 in the form of a rectangular flat plate having the notches 64. Two seat portions 66 for fixation are formed by cutting and raising parts of the peripheral edge of the substrate 65. As the keyboard 60 is set on the upper case 1a, the seat portions 66 are fitted individually on boss portions (not shown) which protrude from the rear face of the upper case 1a. A thin-walled, conductive mounting plate 67 for shielding is fixed to the upper case 1a to cover the rear face of the keyboard 60. Having an external shape corresponding to the size of the keyboard 60, the plate 67 shields the rear face of the keyboard. Fixing holes 68 and positioning brackets 69 are formed at the peripheral edge portion of the plate 67. Principal electronic components are mounted on the rear face of the mounting plate 67. More specifically, a floppy disk drive 71 is mounted on the left-hand half (Fig. 13) of the rear face of the plate 67. A board unit 75 and an L-shaped circuit board 76 are mounted on the right-hand half of the rear face of the plate 67 with an insulating sheet 77 between the board 76 and the plate 67. The board unit 75 includes two circuit boards 72 and 73 which carry thereon various electronic components 72a and 73a, as shown in Fig. 12, for example. These circuit boards 72 and 73 are connected to each other by means of a flexible film cable 74, and are arranged in layers, upper and lower. Further, the board 76 is connected to the board 73 by means of a connector 76a, and is mounted with various electronic components 76b. The connecting terminal 70 of the keyboard 60 is connected to the circuit board 73. A connecting cable 78a, which is led out from the display 2 on the upper case 1a, is connected to a connector (not shown) which is arranged on the circuit board 73. Flexible film cables 78 and 79, which are led out from the circuit board 72, are connected to a battery/card unit 80. The unit 80 is also mounted in the upper case 1a. As shown in Figs. 11 to 13, the unit 80 has an elongated frame 81, and is removably mounted on a flat portion 82 which is situated between the opening 4 and the rear wall of the upper case 1a. The frame 81 has a pair of side walls 83 which are set up on one side, e.g., the left-hand side (Fig. 12), of its rear face. The frame 81 and the side walls 83 constitute a battery box 86. A pair of side walls 84 are set up on the right-hand side of the rear face of the frame 81. The walls 84, along with the frame 81, constitutes a board storing section. Arranged between the side walls 84 is a circuit board 85 which carries a drive units and driver circuits. Numeral 87 denotes a frame for terminal retention. A pair of card storing devices 88, right and left, each having an ejector mechanism (mentioned later), are arranged individually on the opposite sides of the surface (lower surface as in Fig. 12) of the flat portion 82 of the frame 81. The unit 80, having the aforesaid construction, is mounted on the flat portion 82 of the upper case 1a in a manner such that its side carrying the card storing devices 88 are directed to the inner surface of the upper case 1a, and that the circuit board 85 faces the opening of the case 1a. When the unit 80 is mounted in the upper case 1a, various terminals arranged on the terminal holding frame 87 are situated opposite to the openings 5 of the rear wall of the upper case 1a. The unit 80 is screwed to the inner surface of the upper case 1a, and the board unit 75 and the circuit board 76 are screwed to the conductive mounting plate 67. By doing this, various built-in devices are mounted with high density in the upper case 1a so as to cover the entire space in the case 1a, as shown in Fig. 11. The lower case 1b is combined with the upper case 1a, having the various devices thus mounted therein, so as to close the opening portion of the upper case. More specifically, the lower case 1b is fixed to the upper case 1a by means of a plurality of screws 89, with the internal devices between them. In this state, the board unit 75 and the circuit board 76, mounted on the rear face of the keyboard 60, are surrounded by the conductive mounting plate 67 and a plating layer (not shown) on the inner surface of the lower case 1b, as shown in Fig. 14A. Thus, the unit 75 and the board 76 are shielded by means of the conductive layers. As the various boards are arranged on the keyboard 60 with use of the mounting plate 67 for shielding the keyboard, deflection of the keyboard 60 caused by key operation (due to the thinness and low rigidity of the keyboard 60) can be restrained by utilizing the rigidity of the shielding plate 67 for reinforcement. Since all the built-in devices are mounted in the same upper case 1a, moreover, the cables connecting the parts can be reduced in length. Since the display 2 is also mounted in the upper case 1a, the connecting cable 78a for the display 2 can be easily connected to the circuit boards in the upper case, and the cable 78a can be shortened. Thus, the connecting cable 78a can be easily led about in the computer body 1, and can be housed in a relatively narrow space. As shown in Figs. 14A and 14B, a plurality of ribs 90 are formed on the inner peripheral edge portion of the lower case 1b. They serve to support the circuit boards 72, 73 and 76, contained in the upper case 1a, and the keyboard 60 from under the same. As shown in Figs. 10 to 12, legs 91, each in the form of an elliptic projection, are arranged individually at the four corners of the bearing surface of the computer body 1, that is, the lower surface of the lower case 1b. Among these legs, the legs 91 on the right-and left-hand sides of the front portion of the body 1 are situated close to the opposite side faces of the body 1, individually, and have their respective end faces flush with the corresponding side faces. These two legs 91 constitute engaging portions 92 for connection, individually having engaging grooves 92a (only one of which is shown) opening to their corresponding end faces. With use of these engaging portions 92, the personal computer can be positioned with respect to a mounting portion of an expanding apparatus (mentioned later) for expanding the function of the computer. The lower case 1b is formed having an opening 95 (see Figs. 11 and 12) through which a chip (not shown) as an option is incorporated into the circuit board 72 from outside the body 1. Normally, the opening 95 is closed by a cover 96 which is fixed to the lower case 1b by means of a screw 96a. The electronic components mounted on the circuit boards 72, 73 and 76 in the body 1 include superheating members which generate superheat. Accordingly, the whole area of the lower case 1b which adjoins these superheating members is heated to high temperature. As shown in Figs. 10 and 14A, therefore, a number of elongated ridges (projections) 1d are bonded to the front portion of the lower surface of the lower case 1b, extending parallel to one another in the crosswise direction of the body 1. The ridges 1d are formed of a material with a heat transfer rate lower than that of the body 1. Each ridge 1d has a substantially semielliptic cross section, about 1 mm wide and 5 mm high. The space between the respective vertexes of each two adjacent ridges 1d is adjusted to about 2 mm. This key space should only be set lest a user's fingers be caught between the ridges 1d when the user takes hold of the body 1. The ridges 1d may be formed integrally with the lower case 1b from the same material therewith. With use of the numerous ridges 1d thus arranged on the lower surface of the lower case 1b, that is, on that portion of the body 1 which will be heated to high temperature during the operation of the computer, the user's fingers can touch only the vertexes of the ridges 1d, and can never directly touch the lower surface of the lower case 1b, even when the user touches the lower portion of the lower case as he carries the computer. Although the difference in temperature between the ridges 1d and the surface of the lower case 1b is about 1°C, the user will actually feel a temperature difference of 5°C or thereabout. Also, the area of contact of the user's fingers with the lower case 1b is much smaller than in the case where the lower case is not provided with the ridges 1d. If the user touches the underside of the body 1, therefore, he will feel a temperature of only about 40°C to 45°C. Thus, the user can be prevented from harboring suspicion attributable to heat from the body 1, that is, from misguidedly guessing the occurrence of trouble of or damage to the computer. The ridges 1d functions also as antiskid means. As shown in Figs. 1, 14A and 14B, the keyboard 60 5 has a number of keys 63 arranged on a circuit board 60a. These keys 63, which are arranged lengthwise and crosswise, constitute a key array 60b having a substantially rectangular outline as a whole. All the keys 63 except those ones which constitute the outermost lines of the array 60b are each in the form of a truncated pyramid. More specifically, each square key 63 has a rectangular top face 63a and slanting faces 63b which extend obliquely from the individual sides of the top face so as to spread out downward. Thus, each key 63 has a trapezoidal profile. The width a of the top face 63a, width b of the bottom face of the key, tilt angle c of the slanting faces 63c with respect to the top face, and the space d between each two adjacent keys are set at predetermined values for ease of the user's operation. Those keys 63d which constitute the outermost lines of the key array 60b, that is, the right- and left-end lines and the top and bottom lines, have substantially the same shape as the other keys described above. In the keys 63d, however, the tilt angle c of a slanting face 63e on the outline of the array 60b is greater (approximately 90°C) than that of other slanting faces 63c. Accordingly, the outward projection of the keys 63d on the outermost lines from the key array 60b is small, although the area of contact with the user's finger, i.e., the area of the top face.63a, and the space d between the adjacent keys are kept equal to those for the other keys 63. In this case, the width e and depth f of the key array 60b can be made shorter than in the conventional case by (b - a) without changing the size of the key top face and the key space. Thus, the size of the keyboard 60 can be reduced without affecting the ease of use at all. Correspondingly, the whole personal computer can be reduced in size. Since the keyboard size constitutes a primary factor to determine the computer size, in particular, 5 its reduction produces a great effect. The following is a description of the pair of card storing devices 88 arranged in the unit 80. These devices 88, right and left, have the same construction, and Figs. 15 to 23 show an arrangement of the right-hand device 88. Before explaining the card storing device 88, card-type electronic components to be incorporated into the storing device will be described. Available card-type electronic components include, for example, a memory card 97 stored with specific information and an interface card 100 which functions as an interface between the computer and some other external apparatus. As shown in Figs. 15 to 17, the memory card 97 comprises a rectangular circuit board 152, mounted with a plurality of semiconductor elements 150, and a plastic mold frame 153 fitted with the circuit board 152 so as to surround its peripheral edge portion. Rectangular design plates 154, which are formed of conductive metal and serve as a shielding plate each, are mounted on the mold frame 153 so as to cover the upper and lower surfaces of the circuit board 152, individually. Various designs, such as a design coating, are put on the surface of each design plate 154. The memory card 97 is adapted to be inserted into the card storing device 88 of the computer in the direction of arrow A. A connector 156 for electrical connection between the card 97 and the computer is provided at the leading end portion of the card 97 with respect to the card loading direction. The connector 156 constitutes part of the mold frame 153. An engaging recess 157 is formed at a predetermined region of each of two side faces of the mold frame 153 extending in the card loading direction A, at the rear end portion with respect to the loading direction. Engaging grooves 158 are formed individually on the upper and lower surfaces of the frame 153. Each groove 158 extends along the peripheral edge of the mold frame 153 with a narrow space between them. All the peripheral edge portion of each design plate 154 except its front end edge is bent at right angles, thus constituting a retaining portion 159. Those parts of the retaining portion 159 which correspond to the recesses 157 project longer than the other parts, and constitute conductive portions 160 for grounding. Each design plate 154 is formed integrally by press or the like, and each conductive portion 160 is in an exposed ground metal form without any decorative coating. Each design plate 154, constructed in this manner, is fixed to the mold frame 153 in a manner such that the retaining portion 159 is fitted in the retaining groove 158, and the conductive portions 160 in their corresponding recesses 157. Each plate 154 is connected electrically to the ground of the circuit substrate 152 by means of a grounding spring 161 which is fixed to the substrate. The dimensions of the individual parts of the memory card 97 are in conformity to the standards Type II provided by JEIDA. More specifically, the card width is 54.0 ± 0.1 mm, the thickness of the peripheral edge portion (at least 3 mm distant from the edge) of the card is 3.3 mm, and the thickness of the central portion of the card including the design plates 154 is 5.0 mm at the maximum. The interface card 100, like the memory card described above, comprises a circuit board, a mold frame 153 fitted on the periphery of the circuit board, and design plates 154 for use as shielding plates, fixed to the mold frame so as to cover the upper and lower surfaces of the circuit board, individually, as shown in Fig. 18. A connector for electrical connection between the card 100 and the computer is provided at the leading end of the mold frame 153. In the case of the interface card 100, a contact 99 for connection with a connector 98 of an external apparatus, e.g., expanding apparatus (not shown), is arranged at the trailing end with respect to the card loading direction. Further, a metal piece having a substantially U-shaped section is fixed to each side face of the mold frame 153, at the trailing end portion with respect to the loading direction of the card 100, thus constituting a conductive portion 160 for grounding. This metal piece is fixed to the frame 153 in a manner such that it is buried to the depth equivalent to its wall thickness in the frame. The outer surface of the metal piece is flush with the side faces and the upper and lower surfaces of the mold frame 153. The conductive portions 160 and the design plates 154 are connected individually to the ground of the circuit board 152. The following is a description of the card storing device 88. As shown in Figs. 1, 19 and 20, an L-shaped stepped portion 105 is formed in the right-hand corner of the flat portion 82 of the upper case 1a of the computer body 1, which is situated between the keyboard 60 and the rear end portion of the case 1a on which the legs 3 of the display 2 are pivotally mounted. The stepped portion 105 is formed by cutting a predetermined length of the corner portion of the upper case 1a along its ridge-line. A space defined by the stepped portion 105 constitutes an operating opening portion 106 which is externally accessible by a finger tip. A vertical wall of the stepped portion 105, which is continuous with a horizontal wall thereof, has an opening, which defines an elongated inlet slot 107 for the insertion and removal of the memory card 97 or the interface card 100. The slot 107 communicates with a card storing section 108 in the computer body 1. As shown in Figs. 19 and 20, the card storing section 108 is defined by the frame 81, which constitutes the aforementioned unit 80, and the flat portion 82 of the upper case 1a. More specifically, a pair of elongated wall portions 109 are set up parallel to each other on the upper surface of an end portion of the frame 81, so as to be continuous with the opposite crosswise end portions of the inlet slot 107, individually. Each wall portion 109 has a length corresponding to the overall length of the card 97 (or interface card 100). A region surrounded by the wall portions 109, the upper surface of the frame 81, and the inside of the flat portion 82 facing the frame 81 constitutes the flat card storing section 108 which can receive the whole card. The storing section 108 extends from a side face of the upper case 1a toward substantially the crosswise center of the case 1a. When the card 97 (or interface card 100) is received, a connector 110, which can be connected to the connector 156 (see Fig. 15) fixed to the leading end portion of the card 97, is fixed to the flat portion of the frame 81 which corresponds in position to the leading end portion of the card. Thus, when the card 97 or 100 is stored in position in the storing section 108, the connector 156 of the card 97 or 100 is connected to the connector 110. The connector 110 is connected to the board unit 75 by means of a flexible film cable (not shown). The card storing section 108 is provided with a card ejector mechanism 115 of a two-stage drawer type. The card ejector mechanism 115 comprises a card receiver 116, which is arranged in the card storing section 108 and slidable in the card loading direction. As shown in Fig. 20, the receiver 116 is a tray-shaped structure which is formed by, for example, bending a thin metal plate along the lines of the wall portions 109 and the upper surface of the frame 81 between these wall portions. A belt-shaped recess 126 is formed in the center of the bottom wall of the receiver 116, extending in the card loading direction. The receiver 116 can receive the card 97 or 100 inserted through the inlet slot 107. The overall length of the card receiver 116 with respect to the card loading direction is a little shorter than that of the card storing section 108. A pair of L-shaped lugs 117, for use as pressing portions, are cut and raised up individually on the opposite sides of that end of the card receiver 116 on the side of the connector 110. When the card 97 or 100 is inserted into the receiver 116 through the inlet slot 107, the leading end portion of the card with respect to its loading direction abuts against the lugs 117. Thus, when the card is received, the receiver 116 is pushed thereby and together therewith into the inner part of the card storing section 108. The respective extreme ends of the paired lugs 117 are connected to each other by means of a flat connecting piece 164. The piece 164 is bent forward with respect to the card loading direction, and extends substantially parallel to the bottom wall of the card receiver 116. When the receiver 116 is pushed deep into the storing section 108, the connecting piece 164 gets onto and then slides on the upper surface of the connector 110. The width g of the piece 164 in the card loading direction is substantially equal to or a little longer than the stroke of connection between the connector 110 and the connector 156 of the card, that is, the moved distance of the connector 156 covered during the time interval between the contact between the connectors and the completion of the connection. A pair of stopper mechanisms 118 (regulating means) for regulating the advance and retreat of the card receiver 116 are arranged individually on the opposite crosswise sides of the receiver 116. As shown in Fig. 20, each stopper mechanism 118 includes a projection 119, which is formed by raising part of each side wall of the card receiver 116 outward, and a notch 120 formed in part of each wall portion 109 of the card storing section 108 and receiving its corresponding projection 119. The card receiver 116 is slidable between a first position, where each projection 119 abuts against an end edge 120a of its corresponding notch 120 on the side of the connector 110, and a second position, where each projection abuts against an end portion 120b of the notch 120 on the side of the inlet slot 107. The end edge 120a of each notch 120 is positioned so that the whole card in the card receiver 116 can be housed in the card storing section 108 and connected to the connector 110 when the receiver 116 is pushed into the first position where each projection 119 engages the end edge 120a. The end edge 120b of each notch 120 is positioned so that the trailing end portion of the card 97 or 100 in the card receiver 116 projects outward for a predetermined distance from the operating opening portion 106 when the receiver 116 is drawn out to the second position where each projection 119 engages the end edge 120b. In this manner, the movement of the card receiver 116 is restricted within a predetermined range. A conductive metal cover 121 having an L-shaped section is fixed to the frame 81 so as to cover the notch 120 of one of the stopper mechanisms 118, e.g., the left-hand stopper mechanism, from the outside. Thus, the corresponding projection 119 is prevented from slipping out of the notch 120, whereby the card receiver 116 is prevented from being disengaged from the card storing section 108. The distal end of the projection 119 is in sliding contact with the inner surface of the cover 121. The cover 121 is fixed to the frame 81 by means of a screw 122 with the aid of a mount portion 123 formed on the frame 81. The screw 122 connects electrically with the respective plating layers of the upper and lower cases 1a and 1b through the mount portion 122, frame 81, etc. A pair of card conduction portions 124 are formed individually on the respective end portions of the right- and left-hand wall portions of the card receiver 116 on the side of the inlet slot 107. Each conduction portion 124 is formed by bending part of each wall portion into a substantially V-shaped inward projection. when the memory card 97 or the interface card 100 is inserted into a predetermined position in the card receiver 116, the conductive portions 160 on the opposite side faces of the card come into contact with the respective top portions of their corresponding card conduction portions 124, so that the receiver 116 and the card are connected electrically. Thus, when the card 97 or 100 is set in the predetermined position in the receiver 116, it is connected electrically to the computer body 1 to be grounded through the receiver. A drawer piece 125 is provided on that end portion of the bottom wall of the card receiver 116 on the side of the inlet slot 107 so as to be drawable along the card loading direction. As shown in Fig. 20, the piece 125 is formed of a plastic sheet having a substantially T-shaped external configuration. The longitudinally extending portion of the sheet constitutes an operating portion 125a, while a pair of transversely projecting portions constitute retaining portions 127. The operating portion 125a has a slot 130 extending in the card loading direction. The retaining portions 127 of the drawer plate 125 are slidably fitted in a pair of slits 128 (regulating means and connecting means) formed individually in angle portions of the card receiver 116, which define the opening-side ridge-lines of the recess 126, individually. The drawer piece 125 is slidably fixed by means of a guide pin 131, which penetrates the slot 130 and is attached to the bottom wall of the receiver 116. The operating portion 125a is fitted in the recess 126, and extends toward the operating opening portion 106, guided by the recess 126. Thus, the drawer piece 125 is slidable relatively to the card receiver 116 within the range of the length of the slits 128 or the slot 130. More specifically, the piece 125 is slidable between a pushed-in position, where the retaining portions 127 and the guide pin 131 engage the respective connector-side end edges of the slits 128 and the inlet-side end edge of the slot 130, respectively, and a drawn-out position, where the portions 127 and the pin 131 engage the respective inlet-side end edges of the slits 128 and the connector-side end edge of the slot 130, respectively. The slits 128, the slot 130, and the guide pin 131 are positioned so that the end portion (with respect to the drawing direction) of the operating portion 125a is situated in the operating opening portion 106 when the drawer piece 125 is pushed into the pushed-in position, with the card receiver 116 in the first position and the connector 156 of the card connected to the connector 110. Thus, the end portion of the operating portion 125a is located in a position easily accessible by a finger tip inserted in the opening portion 106. Further, the slits 128, the slot 130, and the guide pin 131 are arranged so that the end portion of the operating portion 125a projects long enough from the operating opening portion 106 to enable the user's fingers to seize it with ease when the drawer piece 125 is drawn out to the drawn-out position with the card receiver 116 in the first position. When the drawer piece 125 is drawn out to the drawn-out position so that it is ready for the draw-out of the card 97 or 100, the card receiver 116 and the piece 125 are connected to each other. As shown in Fig. 20, an opening portion 129 (finger catch portion), e.g., rectangular in shape, is formed at that end portion of the operating portion 125a, which is to be located in the operating opening portion 106, so that a finger tip inserted in the opening portion 106 can be hooked to the opening portion 129. By hooking the finger tip in this manner, the user can draw out the end portion of the operating portion 125a from the opening portion 106 to the outside of the upper case 1a or the body 1. As shown in Fig. 1, each operating opening portion 106 is removably fitted with a cover 132 having, e.g., an L-shaped section corresponding to the external shape of the stepped portion 105. The cover 132 is used to close the opening portion 106 so that the card 97 or 100 therein and the end portion of the drawer piece 125 is unseeable from outside the computer after the card is loaded. . In Fig. 20, numeral 133 denotes each of grooves formed individually on the opposite sides of the front face of the connector 110. These grooves 133 receive their corresponding lugs 117 of the card receiver 116 when the receiver 116 is moved to the first position. In Fig. 1, moreover, numeral 135 denotes a floppy inlet slot which is formed in a crosswise side portion of the body 1. A floppy disk can be loaded into a floppy disk drive 71 (see Figs. 11 and 13) in the body 1 through the slot 135. In incorporating the memory card 97 into, for example, the right-hand card storing section 108 of the personal computer constructed in this manner, the cover 132 is first removed from the operating opening portion 106. Then, the card 97 is put into the inlet slot 107, with its leading end side forward and the trailing end side seized by fingers. As a result, the card 97 is inserted deep into the card receiver 116 to be received thereby. If the card receiver 116 is situated in the second position on the side of the inlet slot 107, at this point of time, the leading end of the inserted card 97 abuts against the lugs 117, so that the receiver 116, pushed by the card, moves along with the card toward the first position. When the card 97 is put into the inlet slot 107, the greater part of it is swallowed by the body 1, leaving the seized trailing end portion outside the body 1. Thereafter, the trailing end portion of the card 97, projecting outward from the operating opening portion 106, is pressed so that the whole card 97 is inserted into the card storing section 108 through the slot 107. When the card 97 is pushed in to be stopped by the stopper mechanisms 118, it is held, along with the card receiver 116, in the storing section 108, so that the receiver 116 is situated in the first position. At the same time, the connector 156 at the leading end of the card 97 is connected to the connector 110 on the computer side. In this state, the lugs 117 of the card receiver 116 are in the grooves 133 of the connector 110, and the connecting piece 164 is on the upper surface of the connector 110. Further, the paired conductive portions 160 of the card 97 are individually in contact with the card conduction portions 124 of the receiver 116. Thus, the card 97 connects electrically with the body 1 by means of the card receiver 116 and the frame 81, and also by means of the projections 119 of the receiver, the cover 121, and the screw 122. Accordingly, the design plates 154 of the card 97, which serve as shielding plates, are connected to the ground circuit of the body 1. When the end portion of the drawer piece 125 is projecting from the body 1 through the operating opening portion 106, it is pushed into the pushed-in position by a finger tip, so that it is located in the opening portion 106. Thereafter, when the cover 132 is put on the operating opening portion 106 to close it, the card 97 is incorporated in the body 1 in a manner such that the card 97 and the drawer piece 125 are unseeable from the outside, that is, in an attractive manner. Fig. 21 shows the card in the incorporated state. In incorporating the interface card 100 in place of the memory card 97, the connector 98 of the external apparatus must be connected to the card, so that the cover 132 should not be put on. In taking out the card 97 from the body 1, after finishing the use of the card incorporated in this manner or in order to replace it with another card, the cover 132 is first removed from the operating opening portion 106, as indicated by the arrow in Fig. 22. Then, a finger tip is inserted into the opening portion 106, and hooked to the edge of the opening portion 129 of the drawer piece 125 in the opening portion 106 to pull the piece 125 to the drawn-out position. Thereupon, the end portion of the drawer piece 125 is drawn out from the body 1. Thus, a finger pull portion 134 is formed by drawing out the end portion of the drawer piece 125 long enough for a nip. Subsequently, the drawer piece 125 is drawn out from the body 1 in a manner such that the exposed pull portion 134 is seized by fingers. In doing this, only the piece 125 can be drawn out until the retaining portions 127 of the piece 125 engage their corresponding slits 128, that is, before the piece 125 reaches the drawn-out position. When the retaining portions 127 abut against the respective ends of the slits 128, individually, the drawer piece 125 and the card receiver 116 are connected to each other, and the receiver 116 then also moves toward the inlet slot 107. Since the lugs 117 of the card receiver 116 are in contact with the leading end face of the card 97, the card is pushed and disengaged from the connector 110 as the receiver 116 moves, as shown in Fig. 23. When the receiver 116 is drawn out to the second position, the trailing end portion of the card 97 is led out from the operating opening portion 106 through the inlet slot 107. During this operation, the lugs 117 of the card receiver 116 is subjected to a force from the card 97 such that they are urged to bend in the direction of arrow H in Fig. 20. Since disengaging the connector 156 from the connector 110 requires a great force, in particular, the lugs 117 are also subjected to a great bending force in the direction of arrow H during the disengaging operation. If the lugs 117 are bent in the direction of arrow H, they cannot push the leading end face of the card 97, so that the card cannot be taken out thereafter. In the present embodiment, however, the paired lugs 117 are connected to each other and reinforced by means of the connecting piece 164, which is located on the upper surface of the connector 110. Further, the width g of the piece 164 is longer than the stroke of connection between the connectors 156 and 110. Accordingly, the connecting piece 164 is situated on the upper surface of the connector 110 during the time interval between the start of the operation for disengaging the connector 156 and entire disengagement of the connector 156 from the connector 110. If the lugs 117 are urged to bend in the direction of arrow H, therefore, the connecting piece 164 engages the upper surface of the connector 110, so that the lugs can be prevented from being deformed. When the card 97 is led out, by the above-described operation, to a predetermined position such that the trailing end portion of the card 97 can be seized by fingers, the card 97 is ready to be removed. When the card receiver 116, during the operation for taking out the card, moves to the second position where the trailing end portion of the card 97 is led out for the predetermined distance, it is restrained from further moving by the stopper mechanisms 118, lest it slip out of the card storing section 108. If the trailing end portion of the card 97, projecting to the right from the body 1, is then pulled by fingers, the card 97 can be taken out from the card storing section 108. After the card 97 is removed in this manner, an alternative card 97 or 100 is inserted (in the case of replacement), or the end portion of the drawer piece 125 is pushed so that the card receiver 116 and the piece 125 are restored to their respective original positions, and thereafter, the cover 132 is put on the operating opening portion 106 (if the use is to be discontinued). According to the card ejector mechanism 115, which is constructed so that the hidden end portion of the drawer piece 125 is drawn out in a first drawing stage and the end portion of the card 97 in the card holding section 108 is drawn out and ejected from the body 1 in a second drawing stage, the incorporated card 97, along with the card receiver 116, is housed in the card storing section 108, and the end portion of the drawer piece 125, with respect to the drawing direction, is located in the operating opening portion 106. Thus, the card 97 does not project from the body 1 when it is incorporated therein. Accordingly, the personal computer can be carried with the card therein without hindrance. Since the card ejector mechanism 115 is not linked to any external operating component which requires a specific place for installation, moreover, the installation space for the ejector mechanism is restricted little. Since no recesses or the like which occupy a space over the wall surface of the body 1 are formed at the opposite end portions of the inlet slot 107, moreover, the body 1 cannot be large-sized. Since the paired lugs 117 of the card receiver 116 are connected by means of the connecting piece 164, which is slidable on the upper surface of the connector 110, furthermore, they are improved in mechanical strength, and can be prevented from being deformed. Thus, reliable card ejection can be ensured for a long period of time. When the memory card 97 or the interface card 100 is loaded into the card storing section 108, it is connected to the ground circuit of the body in a low-impedance state through the conductive portions 160 and the card conduction portions 124. Therefore, the computer and the card can be kept at the same ground potential, so that wrong operation of the card attributable to a potential difference can be restrained. Also, the design plates 154 of the card 97 or 100 can be securely connected to the ground, and a satisfactory shielding effect against electromagnetic radiation can be obtained. The conductive portions 160 of each card 97 or 100 are provided individually on the side faces of the card, and their corresponding card conduction portions 124 on the computer side are arranged so as to face these side faces. When the card is loaded into or unloaded from the card storing section 108, therefore, the card conduction portions 124 cannot slide on the upper and lower surfaces of the card, that is, on the design plates 154, so that metallic powder can be prevented from being produced by such sliding motion. Thus, there is no possibility of metallic powder entering the computer body and causing wrong operation of the computer. Further, the coating on the design plates 154 cannot be removed by sliding contact with the card conduction portions 124, and the conductive portions 160 are arranged on the side faces of the card, so that the design plates can be improved in design properties. In the arrangement for the memory card 97, the conductive portions 160 are fitted individually in the recesses in the side faces of the card. When the card 97 is loaded into the card receiver 116, therefore, the card conduction portions 124 are situated in the recesses, and serve to prevent the card from slipping out of the card receiver. Thus, the card 97 can be prevented from being unexpectedly removed from the card receiver 116. As mentioned before, moreover, the conductive portions 160 of each card 97 or 100 are provided individually on the side faces of the card, and their corresponding card conduction portions 124 on the computer side are arranged so as to face these side faces. Even though various cards of different thicknesses are loaded into the card storing section 108, therefore, the conductive portions and the card conduction portions never fail to be brought stably into contact with one another within a predetermined error range (e.g., 0.1 mm). Thus, the card can be securely connected to the ground circuit of the computer body 1, so that a highly reliable shielding effect can be obtained. The paired card storing sections 108 are arranged individuell at the opposite end portions of the flat portion 82 which is situated between the keyboard and the rear portion of the computer body 1 on which the legs 3 of the display 2 are mounted. In the body 1, the region under the flat portion 82 is liable to become a dead space. The space in the body 1 can be effectively used, however, by utilizing this region for the formation of the card storing sections 108. Although the above embodiment has been described with regard to personal computers, it may be applied any other portable electronic apparatus such as word processors. A conductive portion 160 of a card like electronic device according to the invention such as an interface card may extend to the upper and lower surfaces of the card so that it may be directly connected to the design plates 154 serving as shield plates, as shown in Fig. 24. Alternatively, such a conductive portion 160 may be arranged only on a lateral surface of the card without extending to the upper and lower surfaces as illustrated in Fig. 25. Further, as shown in Fig. 26, a conductive portion 160 may be formed by a conductive layer 160a formed on the outer surface of the rear end portion of the card 100.

Claims: A card-shaped electronic device to be used with an electronic apparatus, said device characterized by comprising: a rectangular flat box-like main body to be inserted into and taken out of the electronic apparatus in a given insertion direction, the main body having a pair of lateral sides extending in the insertion direction and upper and lower surfaces; a pair of shield plates (154) fixed to the main body to cover the upper and lower surfaces of the main body, each of the shield plates being formed of a metal and including a bent portion which is fitted on a lateral side of the main body and constitutes a conductive portion (160) for electrically connecting the shield plates with the electronic apparatus when the main body is loaded in the electronic apparatus. A card-shaped electronic device according to claim 1, characterized in that said main body comprises a substantially rectangular circuit board (152) mounted with semiconductors (150), and a rectangular mold frame (153) fitted to the periphery of the circuit board to form the lateral sides of the main body, said conductive portion (160) being disposed on the mold frame. A card-shaped electronic device according to claim 2, characterized in that said mold frame (153) includes a recess (157) formed on the lateral side and each of the bent portions (159) is fitted in the recess. A card-shaped electronic device according to any one of claims 1 to 3, characterized in that said bent portions of the shield plates cooperate to constitute the conductive portion (160). A card-shaped electronic device according to any one of claims 2 to 4, characterized by further comprising means for electrically connecting the shield plates to a ground of the printed circuit board. A card-shaped electronic device according to any one of claims 2 to 5, characterized in that said mold frame (153) includes engaging grooves (158) formed on the upper and lower surfaces and extending along peripheral edges of the mold frame, and each of sald shield plates (154) has a peripheral edge portions (159) which are bent to constitute retaining portions, the retaining portions being fitted in the engaging grooves to position the shield plate at a predetermined position on the mold frame. A card-shaped electronic device according to claim 6, characterized in that the engaging grooves (158) extend along the lateral sides and a rear end of the mold frame (153), respectively. A card-shaped electronic device according to claim 6 or 7, characterized in that at least one of the retaining portions (159) includes said bent portion. A card-shaped electronic device according to any one of claims 1 to 7, characterized by further comprising a connector (156) adapted to be connected to the electronic apparatus, the connector being fixed to a front end of the mold frame (153) with respect to the insertion direction. A card-shaped electronic device according to claim 8, characterized by further comprising a second connector (99) to which an external device is to be connected, the second connector being fixed to a rear end of the mold frame (153) with respect to the insertion direction.

Inventors: INOUE KANJI, KAJI KOICHI, INOUE, KANJI, KAJI, KOICHI
Applicants: TOSHIBA COMP ENGINEERING CORP, TOSHIBA KK, KABUSHIKI KAISHA TOSHIBA, TOSHIBA COMPUTER ENGINEERING CORPORATION
Application year: 1992
Main classification: G06F1
IPC codes: H05K5, G06F1