JPH0236973B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thin and small electronic device.

[Prior art] Conventionally, small electronic devices such as small electronic calculators have been constructed by combining a pair of upper and lower cases made of synthetic resin moldings, and have electronic devices such as wiring boards with integrated circuit elements mounted inside the device case. Some devices are known that have a structure in which device components are housed.

[Problems to be solved by the invention] In recent years, there has been a tendency for small electronic devices such as small electronic calculators to become thinner, and it is now possible to make small electronic devices as thin as credit cards. It is being considered.

However, in conventional small electronic devices, electronic device components are housed in a device case made of synthetic resin as mentioned above, so in order to make the device thinner, the walls of the upper and lower resin cases have to be thinned. This will weaken the strength of the equipment,
For this reason, in conventional small electronic devices, the thickness of the case cannot be made very thin, so the thickness of the device cannot be made as thin as that of a credit card. In addition, in the above-mentioned small electronic devices, it is necessary to take measures against static electricity shielding in order to prevent the integrated circuit elements inside the device from malfunctioning due to the influence of external static electricity. Since the device case is made of synthetic resin, the device case itself cannot shield static electricity, so there is a problem in that a static electricity shielding member such as a metal plate must be provided separately within the device case. Furthermore, there are devices that use only a metal panel as a device case and also have the function of an electrostatic shielding member, but in this case, in order to prevent the internal electronic components from being short-circuited by the metal panel, A space must be provided between the two, which increases the thickness of the device and complicates the structure of the joint between the two.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to significantly reduce the thickness while ensuring sufficient strength, and to provide a separate static electricity shielding member. An object of the present invention is to provide a small electronic device capable of shielding static electricity without causing any damage.

[Means for Solving the Problems] The small electronic device of the present invention has a wiring board, a display panel, etc. having key contacts, and a key display is provided on the top surface of the electronic component structure, and an adhesive is attached to the back surface. A lower cover having a metal sheet on the lower surface is bonded to an upper cover having a top protection sheet, a metal sheet adhered to the top protection sheet, and a spacer provided with contact holes and adhesive adhered to the front and back surfaces. A metal frame is disposed between the upper and lower covers, and the metal sheets of the upper and lower covers and the frame are electrically connected.

[Function] According to the small electronic device of the present invention, an upper cover having a metal sheet is integrated with the top surface of the electronic component component by means of a spacer whose front and back surfaces are coated with an adhesive. The bottom cover, which includes metal sheets, is integrated with adhesive on the bottom surface, so the upper and lower metal sheets can ensure the strength of the device, and the upper and lower metal sheets can be attached to the top and bottom of the electronic component structure. Since it is laminated on both sides, its thickness can be made much thinner than conventional small electronic devices. Moreover, the electronic component component is housed in a metal frame placed between the upper and lower covers, and the metal sheets of the upper and lower covers and the frame are electrically connected.
Static electricity from the outside can be reliably shielded.

[Embodiments of the Invention] Examples of the present invention will be described below with reference to drawings.

A first embodiment of the present invention will be described with reference to a sheet-like small electronic calculator shown in FIGS. 1 to 11.

FIG. 2 shows the external appearance of the sheet-like small electronic calculator, and FIG. 3 shows the disassembled state. In the figure, 1 is an electronic component structure, 2 is an upper cover, and 3 is a lower cover. The electronic component structure 1 is configured by combining a wiring board 11, a semiconductor integrated circuit element 12, an electronic component 13, a display panel 14, and a solar cell 15. The upper cover 2 includes a metal sheet 16 as its main body, a top protection sheet 18, a spacer 17,
and a pair of frames 19 are stacked together. The lower cover 3 is constructed by laminating a metal sheet 20, which is the main body thereof, and a lower surface protection sheet 21. Third
Although not shown in the drawings, reference numeral 4 in FIG. 1 and FIGS. 4 to 6 indicates an adhesive layer made of an insulating adhesive 22. Then, the upper cover 2 is closely laminated on the upper side of the electronic component structure 1, the adhesive layer 4 is provided on the lower side of the electronic component structure 1, and the lower cover 3 is closely laminated on the lower side of the adhesive layer 4. The whole thing is in the form of a thin sheet.

Next, the structure of each part will be described with reference to FIG. 1 and FIGS. 4 to 8. Figure 1 is a cross-sectional view taken along line A-A in Figure 2, Figure 4 is a cross-sectional view taken along line B-B in Figure 2, Figure 5 is a cross-sectional view taken along line C-C in Figure 2, and Figure 6 is a cross-sectional view taken along line C-C in Figure 2. 7 and 8 are cross-sectional views taken along the line D-D in the figure, respectively, and FIGS. 7 and 8 are drawings showing the switch portion, respectively.

The electronic component structure 1 will be described. Wiring board 1
1 is a rectangular sheet made of an insulating material and has a thickness of about 220 μm. On the top surface, a plurality of fixed contacts 23, each consisting of a pair of contacts, are arranged in a grid pattern as switch contacts. and a fixed contact 23 and a terminal 2 to be described later on the bottom surface.
A predetermined wiring pattern including lines 4 and 28 is formed. Semiconductor integrated circuit elements 12 and electronic components 13 such as chip capacitors and diodes are attached to the mounting holes 11a formed in the wiring board 11 by penetrating the upper and lower sides thereof, and these are connected to the wiring pattern of the wiring board 11. The display panel 14 is composed of a liquid crystal display panel packaged with a liquid crystal film and has a thickness of about 550 μm.A liquid crystal is sealed between upper and lower films that serve as upper and lower electrode substrates, and one end 14a of the film is sealed. be. The display panel 14 is disposed on one side of the wiring board 11 on the same plane. As shown in FIG. 1, terminals 24 formed on the lower surface of the wiring board 11 and terminals 25 formed on the lower surface of the upper electrode substrate of the display panel 14 are connected by a flexible film 27 having wiring 26 made of conductive adhesive. The terminals 24, 25 and the wiring 26 are bonded together by heating and pressing. The solar cell 15 has a thickness of approximately 180 μm and is made by forming an alumofous silicon thin film on the upper surface of a substrate made of stainless steel.
are arranged coplanarly on one side of the . Fourth
As shown in the figure, terminals 28 formed on the lower surface of the wiring board 11 and terminals 29 formed on the upper surface of the substrate of the solar cell 15 are connected by a flexible film 31 having wiring 30 made of conductive adhesive. The terminals 28 and 29 are bonded together by heating and pressing. In this case, the wiring 30 is formed on the opposite surface of the flexible film 31 so as not to shoot against the substrate side of the solar cell 15.
A wiring 30 is led out to the solar cell 15 side through a through hole 31a at the terminal 29 portion, and is electrically connected to the terminal 29. In this way, the electronic component structure 1 is constructed by arranging each component in a plane and electrically connecting each component to the semiconductor integrated circuit element 12.
uses the solar cell 15 as a power source to perform a calculation operation based on the input signal from the fixed contact 23, outputs a display signal to the display panel 14, and displays the calculation result.

The upper cover 2 will be described. The metal sheet 16, which is the main body of the upper cover, is made of a metal plate, for example, a stainless steel plate, with a thickness of about 100 μm, and has a rectangular shape corresponding to the entire frame 19. This metal sheet 16 also serves as a contact sheet, and a plurality of contact springs 32 having the shape shown in FIG. In addition, a display window 33 and a battery window 34 are formed by etching to correspond to the display panel 14 and the solar cell 15, and a plurality of holes are formed on the lower surface to correspond to the integrated circuit element 12 and electronic components 13. A relief recess 35 is formed by half-etching. By printing carbon paint on the lower center surface of each contact spring 32,
A movable contact 36 is provided as an operation section for inputting input to the fixed contact 23. Note that an escape recess 34a is formed in the battery window 34 of the metal sheet 16 to allow the wiring 30 of the flexible film 31 to escape. The spacer 17 maintains the distance between the metal sheet 16, which also serves as a contact sheet, and the wiring board 11, and is made of a transparent polyester film with a thickness of about 50 μm, and has a rectangular shape corresponding to the size of the wiring board 11. I am doing it. A plurality of contact holes 37 are formed in the spacer 17 in a grid pattern at positions facing each of the fixed contacts 23 of the wiring board 11, and a plurality of relief holes 38 are formed corresponding to the integrated circuit element 12 and each electronic component 13. is formed. Note that a transparent insulating adhesive 43 having a thickness of approximately 25 μm is applied in advance to the upper and lower surfaces of the spacer 17, respectively. The frame 19 is formed of a metal plate, for example, a stainless steel plate, with a thickness of about 400 μm, and has a size that surrounds the electronic component structure 1, and has a protrusion 19a that partitions the display panel 14 and the solar cell 15. do,
The entire frame is rectangular. As shown in FIGS. 5 and 6, a contact piece 39a cut upward and a contact piece 39b cut downward are provided at appropriate locations on the frame 19 for electrostatic shielding. It has been formed. The top protection sheet 18 protects the top surface of the metal sheet 16 and has a thickness of 50 μm.
Made of transparent polyester film,
It has a rectangular shape slightly larger than the metal sheet 16. This protective sheet 18 has opaque printing applied to the entire lower surface of the protective sheet 18, except for the transparent display section 40 of the display panel 14 and the light receiving section 41 of the solar cell 15, and also has a pattern corresponding to each contact spring 32 of the metal sheet 16. A display printout 42 is printed to display input items for the switch contacts. Furthermore, a transparent insulating adhesive 43 having a thickness of approximately 25 μm is applied to the entire lower surface of the upper surface protection sheet 18. The spacer 17 is placed on the upper surface of the wiring board 11 of the electronic component assembly 1, and the wiring board 11 is bonded to the wiring board 11 by an insulating adhesive 43 applied to the lower surface of the spacer 17. It is bonded to the spacer 17 by an insulating adhesive 43 placed on the upper surface and applied to the upper surface of the spacer 17 . Further, the upper protective sheet 18 is placed on the upper surface of the metal 16 and is bonded to the metal sheet 16 by a transparent insulating adhesive 43 applied to the lower surface of the upper protective sheet 18. In addition, the frame body 19
is arranged on the lower side of the metal sheet 16 surrounding the electronic component structure 1 and the spacer 17,
It is adhered to the lower surface of the metal sheet 16 via an adhesive 43. As shown in FIG. Each fixed contact 23 of the wiring board 11 is inserted through the hole 37.
Located above and facing. Top protection sheet 18
Each item of the display print 42 is located above each contact spring 32. This constitutes a switch.
Since the contact spring 32 of the metal sheet 16 is always in a horizontal state due to the spring force as shown in FIG.
The movable contact 36 is spaced apart from the fixed contact 23,
In addition, as shown in FIG.
When the display print 42 is pressed down, the contact spring 32 of the metal sheet 16 also bends downward against the spring force and enters the contact hole 37 of the spacer 17, causing the movable contact 36 to connect to the fixed contact 23 of the wiring board 11.
come into contact with. Therefore, the pair of contacts of the fixed contact 23 are electrically connected to each other. Further, as shown in FIG. 1, the display transparent part 40 of the top protection sheet 18 and the display window 33 of the metal sheet 16 are vertically overlapped, and the upper part of the display panel 14 fits into the display window 33 to display the display. The surface faces the transparent display see-through section 40. Therefore, the display on the display panel 14 is displayed on the display transparent section 40.
Can be read externally via . In addition,
The upper surface of the display panel 14 is adhered to the upper surface protection sheet 18 with a transparent insulating adhesive 43. Also,
As shown in FIG. 4, the light receiving section 41 of the protective sheet 18
The battery windows 34 of the metal sheets 16 are stacked vertically, and the solar cells 15 are fitted into the battery windows 34 so that the battery elements face the transparent light receiving section 41. Therefore, the solar cell 15 can receive external light via the light receiving section 41. Note that the solar cell 15 is adhered to the protective sheet 18 via a transparent insulating adhesive 43. As shown in FIG. 1, the escape recesses 35 of the metal sheet 16 and the escape holes 38 of the spacer 17 overlap vertically, and the integrated circuit element 1 mounted on the wiring board 11
2 and the escape hole 38 where the upper part of each electronic component 13 faces each other.
and is fitted into the escape recess 35. Note that the integrated circuit element 12 and the electronic component 13 are electrically insulated from the metal sheet 16 by a layer of insulating adhesive 43. In this way, the upper cover 2 is laminated in close contact with the entire upper surface of the electronic component structure 1.
In this embodiment, a frame 1 is used as a part of the upper cover 2.
9 is provided, and this frame body 19 holds the electronic component structure 1 from the periphery.

The adhesive layer 4 will be described. The adhesive layer 4 is formed of an acrylic or epoxy two-component insulating adhesive 22. The adhesive 22 is applied to the entire lower surface of the wiring board 11 in the electronic component assembly 1, and is filled to cover the integrated circuit element 12 protruding from the lower surface of the wiring board 11 and the lower part of each electronic component 13. The agent 22 is filled to cover the lower part of the display panel 14, and is also filled to fill the lower space of the solar cell 15. Furthermore, the adhesive 22 surrounds the entire outer periphery of the frame 19 in the upper cover 2 and protects the protective sheet 18 of the upper cover 2 and the protective sheet 21 of the lower cover 3.
It is filled in between. In this way, the adhesive layer 4 is formed by filling the entire lower surface of the electronic component structure 1 with the adhesive 22 in a layered manner.
Each component is bonded and fixed from below, and irregularities of each component on the lower side of the electronic component structure 1, that is, variations in height of each component are absorbed.
If a case structure constituting the device case is provided below the electronic component structure 1 instead of the adhesive layer 4, the structure will be complicated in order to fix the electronic component structure 1, and the electronic component structure will be It is difficult to absorb the irregularities of each component of the electronic component structure 1, and it is especially difficult to absorb the irregularities when an error occurs in the mounting dimensions of the components of the electronic component structure 1 or the thickness of the component itself during assembly. On the other hand, since the adhesive layer 4 of this embodiment has fluidity, it can absorb the unevenness of each component of the electronic component structure 1 while reliably fixing each component, especially when attaching each component during assembly. It can flexibly absorb errors in dimensions and thickness of the parts themselves. Further, in this embodiment, since the adhesive 22 adheres and fixes the outer periphery of the frame 19 between the protective sheets 18 and 21, the strength of the sheet-like small electronic calculator can be increased, and the small electronic calculator The adhesive 22 covers the laminated seams of each component on the outer periphery of the computer to improve its appearance.

The lower cover 3 will be described. The metal sheet 20, which is the main body of the lower cover 3, is made of a metal plate, for example, a stainless steel plate, with a thickness of about 100 μm, and has a rectangular shape with the same size as the frame 19 of the upper cover 2. The lower surface protection sheet 21 is formed of a transparent polyester film with a thickness of about 25 μm, and the metal sheet 2
It has a rectangular shape slightly larger than zero, and a transparent insulating adhesive 43 with a thickness of about 25 μm is applied to the upper surface side. The metal sheet 20 is placed overlappingly on the lower surface of the adhesive layer 4 and fixed by adhesive.
The upper surface of the metal sheet 20 is coated with an insulating adhesive 43 on the portion facing each component of the electronic component structure 1 in order to insulate the metal sheet 20 from each component. The lower surface protection sheet 21 is overlaid and adhesively fixed to the lower surface of the metal sheet 20 via an adhesive 43. In this case, since the adhesive 22 flows and receives the lower cover 3, the lower cover 3 can be set parallel to the upper cover 2 and at the required spacing position with high precision. ) can be freely adjusted at the manufacturing stage. The metal sheet 20 supports the adhesive layer 4 from below, and the lower surface protection sheet 21 protects the lower surface of the metal sheet 20. The upper surface of the lower surface protection sheet 21 is printed, for example, for decoration. is being done.

This sheet-like small electronic calculator has contact sheet 1.
6. Since the frame 19 and the support sheet 20 are made of a metal plate, such as a stainless steel plate, the entire computer has high mechanical strength and rigidity. Also, the thickness of this sheet-like small electronic calculator is
It is 800μ.

Furthermore, this sheet-like small electronic calculator
Electrostatic shielding measures are taken using the upper cover 2 and lower cover 3. That is, the fifth
As shown in the figure, an upward contact piece 39a formed on the frame body 19 contacts the lower surface of the metal sheet 16 of the upper cover 2, and a downward contact piece 39b formed on the frame body 19 as shown in FIG. It is in contact with the upper surface of the metal sheet 20 of the cover 3. Therefore, since the metal sheet 16 located on the upper side and the metal sheet 20 located on the lower side are electrically connected at the same potential through the metal frame 19, static electricity from the outside is absorbed by one metal sheet. By discharging static electricity from the sheet 16 or 20 to the other metal sheet 20 or 16, it is possible to reliably prevent the influence of static electricity from reaching the semiconductor integrated circuit element 12 of the wiring board 11.

Next, a method of manufacturing a sheet-like small electronic calculator having the above-mentioned configuration will be explained. First, in the electronic component structure 1, the integrated circuit element 12 and each electronic component 13 are mounted on the wiring board 11 with its surface (top surface) as a reference position, and the display panel 14 and the solar cell 1 are mounted.
5 is connected to the wiring board 11 using flexible films 27 and 31 and assembled. The upper cover 2 is made by adhesively fixing the frame 19 to the lower surface of the metal sheet 16 using an adhesive 43 using a heating and pressing method, and then attaching the upper protective sheet 18 to the upper surface of the metal sheet 16 using an adhesive 43.
3, and is assembled by adhesion and fixation by heating and pressing. Then, the electronic component structure 1 and the metal sheet 1
6 and a laminate of the upper surface protection sheet 18 are stacked on top of each other with the spacer 17 in between.
7. Adhesive fixation is performed by heating and pressing via adhesive 43 applied to both surfaces. In this case, the surface side of the upper surface protection sheet 18 is used as a reference surface for bonding. As a result, the upper cover 2 and the electronic component assembly 1 are assembled, and the upper surface side of the upper cover 2 becomes a flat surface.
Note that the lower side of the electronic component structure 1 has an uneven state in which each component protrudes (see FIGS. 9 and 10). Next, as shown in FIG.
A stacked body of the electronic component structure 1 and the electronic component structure 1 is arranged with the upper cover 2 facing down, and the back side of the electronic component structure 1 is positioned on the top side. Electronic component structure 1 on the upper side
An adhesive 22 is filled in the upper part and outer periphery of the laminate including the back side of the laminate. Since the adhesive 22 has fluidity, it easily enters the recesses between the parts on the back side of the electronic component structure 11 and covers and embeds the convex parts of each component. The adhesive layer 4 is formed by absorbing the irregularities and dimensional variations of the parts on the back side. Next, the metal sheet 20 and the protective sheet 21 are glued together with adhesive 4.
The lower cover 3 is manufactured by adhering and fixing the lower cover 3 to each other using the heat and pressure method via the lower cover 3, and as shown in FIG. do. The lower cover 3 is placed parallel to the upper cover 2 so that the total pressure is
Roll down to a position of 800μ. In this case, since the adhesive 22 flows toward the outer periphery pressed by the lower cover 3, the lower cover 3 can be lowered to a preset height position. Therefore, the upper cover 2 and the lower cover 3 can be arranged in parallel with high precision, and the thickness between the upper cover 2 and the lower cover 3 can be set with high precision relative to the design value. Note that the excess adhesive 22 is used as a protective sheet 18 of the upper cover 2.
It flows between the protective sheet 21 of the lower sheet 3 and protrudes to the outer periphery. Next, Figures 10 and 11
As shown in the figure, the outer periphery of both the protective sheets 18, 21 and the adhesive 22 between the protective sheets 18, 21 is cut into the final shape shown by the broken line. For this cutting, both protective sheets 18 and 21 are previously formed larger than their final shape at the manufacturing stage. After cutting into the final shape, both protective sheets 1
The adhesive 22 present between 8 and 21 hides the upper and lower metal sheets 16 and 20 and the outer periphery of the frame 19, and protects the periphery of the sheet-like small electronic calculator together with the resin protective sheets 18 and 21. It can give the appearance of resin spacing.

That is, the sheet-like small electronic calculator of the above embodiment has an upper cover 2 mainly composed of a metal sheet 16 and a metal frame 19 adhered to the lower surface thereof, and a lower cover 3 mainly composed of a metal sheet 20. This upper cover 2 constitutes the case body of the calculator.
Between the lower cover 3 and the lower cover 3, an electronic component assembly 1 is housed, in which a display panel 14 and a solar cell 15 are connected to a wiring board 11 on which an integrated circuit element 12 and an electronic component 13 are attached.
A metal sheet 16 constituting the upper cover 2 is laminated on the upper surface of the wiring board 11 via a spacer 17, and an adhesive 43 is applied to the upper and lower surfaces of the spacer 17.
The metal sheet 20 constituting the lower cover 3 is then laminated on the lower surfaces of the wiring board 11, display panel 14, and solar cell 15 of the electronic component structure 1, and the adhesive layer 4 made of an insulating adhesive 22 and the metal Insulating adhesive 43 applied to the top surface of the sheet 20
According to this sheet-like small electronic calculator, there are a metal sheet 16 constituting the upper cover 2 and a metal sheet 20 constituting the lower cover on the upper and lower surfaces, respectively. The strength of the upper and lower surfaces of the computer can be ensured by the metal sheets 16 and 20, and the computer can be constructed by laminating the upper and lower metal sheets 16 and 20 on the upper and lower surfaces of the electronic component structure 1, respectively. As a result, the thickness of the device can be significantly reduced compared to conventional small electronic devices in which electronic device components are housed in a device case that combines a pair of upper and lower cases made of resin molded products. In addition, in the sheet-like small electronic calculator of the above embodiment, the upper cover 2
Since the metal sheet 16 constituting the calculator and the metal sheet 20 constituting the lower cover 3 are electrically connected, static electricity from the outside can be removed from the upper cover 2 and the lower part of the computer without providing a separate static electricity shielding member as in the past. It can be shielded using the cover 3.

Next, a second embodiment of the present invention will be described with reference to FIG. This second embodiment is applied to a sheet-like small electronic computer like the first embodiment described above, and in FIG. 12, the same parts as in FIGS. 1 and 3 are given the same reference numerals and explained. omitted.

In this second embodiment, the adhesive 22 of the adhesive layer 4 is provided between the electronic component structure 1 and the lower cover 3, and the adhesive 22 of the adhesive layer 4 is provided between the metal sheet 16 of the upper cover 2 and the metal sheet 20 of the lower cover 3. The outer periphery of the frame 19 is surrounded and filled, and the upper and lower metal sheets 16,
20 are electrically connected via a frame 19. In this case, the strength of the outer periphery is improved.

[Effects of the Invention] According to the small electronic device of the present invention, since the upper and lower covers each having a metal sheet are adhered to the upper and lower surfaces of the electronic component structure, the large width can be maintained while ensuring sufficient strength. Furthermore, since the metal frame housing the electronic components is electrically connected to the upper and lower metal sheets, static electricity from the outside can be reliably shielded. The top protection sheet has adhesive attached to the top and the spacer has adhesive attached to the front and back sides.
This also has the effect of efficiently and reliably adhering the metal sheet and the top protection sheet and the metal sheet and the electronic component structure.

[Brief explanation of drawings]

1 to 11 show a first embodiment of the present invention, in which FIG. 1 is a sectional view taken along line A-A in FIG. 2, and FIG. 2 is an external view showing a sheet-like small electronic calculator. , Figure 3 is an exploded perspective view, Figure 4 is Figure 2B-
5 is a sectional view taken along the line C-C in FIG. 2, FIG. 6 is a sectional view taken along the line D-D in FIG. 2, and FIG. 7 shows the contact spring of the contact sheet. 8 is a cross-sectional view of the switch section showing the operating state of the switch; FIGS. 9 and 10 are explanatory diagrams showing the manufacturing process of the sheet-like small electronic calculator;
FIG. 1 is a perspective view showing a semi-finished product of a sheet-like small electronic calculator. FIG. 12 is a sectional view of a sheet-like small electronic calculator showing a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Electronic component structure, 2... Upper cover, 3... Lower cover, 4... Adhesive layer, 11... Wiring board, 12
... integrated circuit element, 13 ... semiconductor component, 14 ... display panel, 15 ... solar cell, 16 ... metal sheet, 1
7... Spacer, 18... Top protection sheet, 19... Frame, 20... Metal sheet, 21... Bottom protection sheet,
22...Adhesive, 23...Fixed contact, 32...Contact spring, 33...Display window, 34...Battery window, 36...Movable contact, 40...Display transparent section, 41...Light receiving section, 43...Insulating adhesive.

Claims (1)

[Scope of Claims] 1. An electronic component structure in which a wiring board having a key contact, a semiconductor integrated circuit element, a display panel, and a battery are electrically connected, and a key display corresponding to the key contact and facing the display panel. a top protection sheet provided with a display window and adhesive adhered to the back surface; a metal sheet having a display window facing the display panel opened and bonded to the top protection sheet; a position facing the key contacts; A contact hole is provided on the front and
an upper cover having a spacer on each back side with an adhesive adhered to the metal sheet and the upper surface of the electronic component structure; and a lower cover including at least a metal sheet and adhered to the lower surface of the electronic component structure. , a metal frame provided between the upper cover and the lower cover and accommodating the electronic component structure, and electrically connecting the metal sheets of the upper and lower covers and the frame. A small electronic device characterized by being connected to.