JPS6362016B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to small electronic devices.

[Conventional technology]

In the case of small electronic devices such as small electronic calculators, an upper case and a lower case that are molded synthetic resin are combined, electronic components such as wiring boards are housed inside the case, and the combined upper case and lower case are combined. A structure is adopted in which the two cases are joined together by passing screws into screw holes formed in the lower case and tightening them.

[Problem that the invention seeks to solve]

Incidentally, in recent years, there has been a trend toward thinner small electronic devices such as small electronic calculators in order to improve portability, and recently the thickness of small electronic devices has been reduced to be similar to that of credit cards. The goal is to make it as thin as possible.

However, in the past, the upper case and lower case of a synthetic resin molded product were connected by passing screws into screw holes formed in each case and tightening them. If it is made thinner, the screw hole part of each case will also be thinner, and there is a risk that the case will be damaged from the screw hole part when the screw is tightened. For this reason, there is a problem in that it is difficult to make the device as thin as a credit card while maintaining mechanical strength as a whole.

The present invention was made based on the above circumstances, and
The purpose of this invention is to provide a compact electronic device that can ensure sufficient strength while being significantly thinner.

[Means to solve problems]

In order to achieve the above object, a small electronic device of the present invention includes a wiring board on which a predetermined wiring pattern including key contacts is formed and an opening larger than the outer shape of a semiconductor integrated circuit element, and a wiring board arranged in the opening. an electronic component structure having a semiconductor integrated circuit element connected to the wiring board; a display element and a battery arranged side by side on the wiring board and fixedly bonded to the wiring board with a conductive adhesive; A frame formed to surround the outer periphery of the wiring board, the display element, and the battery that constitute a component structure and formed thinner than the thickness of the display element, and a key display section facing the key contact point. , and a see-through window of the display element, and
A sheet-like upper case is laminated in close contact with the upper side of the electronic component structure and is bonded to the upper surface of the frame, and a display element recessed part facing the display element is provided below the electronic component structure. It is characterized by comprising a lower case that is laminated in close contact with the sides.

[Effect]

According to this configuration, the semiconductor integrated circuit element is placed in the opening of the wiring board and connected to the wiring board, and the frame for housing the electronic component structure is formed thinner than the thickness of the display element, and the lower case is Since the display element recessed portion is formed in the lower case, the mechanical strength of other parts of the lower case can be ensured.
Furthermore, since the upper case, electronic components, and lower case are bonded to each other with adhesive without providing screw holes in the case, sufficient strength can be ensured while making the entire device thinner.

〔Example〕

Embodiments of the present invention illustrated in the drawings will be described below.

An embodiment in which the small electronic device of the present invention is applied to a small electronic calculator will be described. 1 to 25 show an embodiment of the present invention.

FIG. 2 is an external view of the small electronic calculator of this embodiment, and FIG. 1 is an exploded view of the small electronic calculator.
In the figure, 11 is an electronic component structure, 12 is a top sheet, 13 is an upper sheet, 14 is a bottom sheet, 1
5 is a lower sheet, and 16 is a frame. Each of these sheets 12, 13, 14, 15 and frame 16 has a rectangular outer shape with the same size. The top sheet 12 and the top sheet 13 constitute a sheet-like upper case 1 by laminating them in close contact with each other,
The lower sheet 14 and the lower sheet 15 are in close contact with each other to constitute a sheet-shaped lower case 2. Then, the electronic component structure 11 is surrounded and supported by the frame 16, and the upper case 1 is bonded and laminated on the upper side of the electronic component structure 11 and the frame 16.
A lower case 2 is bonded and laminated on the lower side of the electronic component structure 11 and the frame 16. In this way, a small electronic calculator in the form of a rectangular sheet is assembled.

The configuration of each part of the small electronic calculator will be explained with reference to FIGS. 3 to 19. 3 to 10 are plan views showing each component. 11 to 14 are cross-sectional views showing the laminated structure,
Figure 11 shows the boundary between the board and the frame (part A in Figure 2),
Figure 12 shows the part where the operation switch is installed (Figure 2B
part), Figure 13 shows the part where the display element is installed (part C in Figure 2), and Figure 14 shows the part where the battery is installed (part D in Figure 2).
The cross-sections of each part) are shown. Electronic component structure 1
1 to Figures 3 and 4, Figures 13 to 19
Let's talk about the diagram. As shown in FIGS. 3 and 4, the substrate 21 is made of glass epoxy resin or bismaleide-triazine resin and has a rectangular sheet shape with a thickness of about 190 μm, and has a predetermined wiring pattern on its upper and lower surfaces. A copper foil 22 with a thickness of about 35 μm forming the structure is bonded via an insulating adhesive 23 with a thickness of about 20 μm. The wiring patterns formed by the copper foil 22 on the upper and lower surfaces of the substrate 21 include wiring, contacts, and terminals, and each wiring pattern on the upper and lower surfaces is formed through through holes (not shown) formed at predetermined locations on the substrate 21. Connected. The wiring pattern on the upper surface of the substrate 21 is schematically shown in FIGS. 3 and 4, and connects fixed contacts, capacitors, display elements, batteries, light emitting diodes, etc. around the integrated circuit element. Substrate 21
On the upper half of the upper surface, a plurality of fixed contacts 24, which are switch elements, are arranged in a grid pattern as part of the wiring pattern. It is connected to an integrated circuit element 26, which will be described later, via a wiring pattern. As shown in FIG. 15, in the other half of the board 21, a hole 25 is formed leaving the wiring pattern (copper foil 22 and adhesive 23) on the lower surface, and a predetermined calculation is performed by turning on and off the switch element. A semiconductor integrated circuit element 26, ie, a large-scale integrated circuit (LSI), is supported by a wiring pattern on the lower surface side. That is, the hole 25 has an opening shape that is larger than the integrated circuit element 26. This integrated circuit element 26 is connected to the substrate 21 through gold wires 27.
It is connected to the wiring pattern (copper foil 22) on the upper surface side, and is covered from above with an insulating resin 28 such as silicone rubber or epoxy resin to seal the whole. The integrated circuit element 26 is made of a rectangular chip measuring, for example, 4 mm long x 4 mm wide x 200 μm thick, and the resin 28 is, for example, 10 mm long x 10 mm wide x 245 μm thick from the top surface of the integrated circuit.
In the hole 29 formed in the other half of the board 21, leaving the wiring pattern (copper foil 22 and adhesive 23) on the lower surface, a chip capacitor 30 is inserted into the lower wiring as shown in FIG. 16c. The electrodes 30a formed at both ends of the capacitor 30 are bonded to the cream solder 31 applied to the hole 29 and connected to the wiring pattern (copper foil 22) on the top surface of the board 21. At the same time,
The periphery of the substrate 21 is covered with an insulating adhesive 32 applied to the upper surface of the substrate 21, such as ultraviolet curing ink. This capacitor 30 is connected to the integrated circuit element 26 via a wiring pattern. The corner of the other end of the board 21 is cut out leaving the wiring pattern (copper foil 22 and adhesive 23) on the bottom side, and the 17th corner is cut out at this location.
As shown in FIG.
a is adhered to the cream solder 31 applied to the board 21, and the wiring pattern (copper foil 2
2), and the periphery is sealed with an insulating adhesive 32, such as ultraviolet curable ink, applied to the upper surface of the substrate 21. The light emitting diode 33 is connected to the integrated circuit element 26 via a wiring pattern.
A display element 34, ie, a liquid crystal panel, is arranged on one side edge of the substrate 21, and is connected to the wiring pattern on the upper surface side of the substrate 21. Display element (liquid crystal panel)
As shown in FIG. 18, 34 is made of a transparent resin film such as a polyester film with a polarizer layer therein, and a liquid crystal 37 is sealed between upper and lower substrates 35 and 36 provided with electrodes, and the periphery thereof is sealed. 38
and seal it with a thickness of 50 μm on the lower surface of the lower electrode base 36.
The reflector plate 39 is bonded with an adhesive having a thickness of approximately 15 μm. A plurality of terminal electrodes 40 made of transparent conductive ink are connected to the electrodes of each electrode base 35 and 36 on the upper surface of the protrusion of the lower electrode base 36.
... are arranged in the longitudinal direction. The display element (liquid crystal panel) 34 has a total thickness of about 550 μm, and has elasticity (toughness) due to the use of a film base. Further, at one end of the upper surface of the board 21, a plurality of terminals 41 are formed by extending the copper foil 22 of the wiring pattern and arranged in the longitudinal direction, and these terminals 41 project laterally from the board 21. There is. The terminal electrodes 40 of the display element (liquid crystal panel) 34 and the terminals 41 of the substrate 21 are bonded and electrically connected to each other by applying a conductive adhesive 42 such as carbon ink to their respective contact surfaces. The surrounding area is coated with an insulating adhesive 32, such as ultraviolet curable ink. The display element 34 is connected to the integrated circuit element 26 via the wiring pattern of the substrate 21.
It is connected to the integrated circuit element 26 and displays predetermined information based on the signal from the integrated circuit element 26. On one side edge of the substrate 21, an integrated circuit element 2 is arranged along with a display element 34.
A battery 43, such as a solar battery, for supplying driving voltage to the circuit board 6 is disposed and connected to the wiring pattern of the substrate 21. Battery (solar battery) 43 is the 19th
A metal substrate 44 such as stainless steel as shown in the figure
An amorphous solar cell layer 46 is deposited on the upper surface through an insulating layer 45 with a thickness of about 25 μm, for example, polyimide, and a protective layer 46 is further deposited on the solar cell layer 46 to a thickness of about 25 μm.
Covered with a polyester film 47 of about 175μ,
Further, a pair of terminal electrodes 48, 48 are formed on the upper surface of the metal substrate 44 with an insulating layer 45 interposed therebetween.
This cell (solar cell) 43 has a total thickness of about 300 μm and has elasticity (toughness) as a whole. Furthermore, a pair of terminals 49 are formed on one edge of the substrate 21 at a location facing the battery (solar cell) 43 by making the copper foil 22 of the wiring pattern protrude laterally. The terminal electrode 48 of the battery (solar cell) 43 and the terminal 49 of the base 21 are each coated with a conductive adhesive 42.
For example, they are electrically connected by applying carbon ink and adhering them to each other, and the periphery thereof is covered with an insulating adhesive 32, such as an ultraviolet curable ink. For this reason, the battery (solar cell) 43
are connected to the integrated circuit element 26 via the wiring pattern of the substrate 21.

The electronic component assembly 11 configured in this manner is placed inside the frame 16. The frame 16 has a thickness of about 300 μm, which is thinner than the display element 34 made of hard vinyl chloride, for example, and the frame 16 has a rectangular frame shape as shown in FIG. 10, and the inside thereof has electronic components. Depending on the arrangement of the parts of the structural body 11, the shape extends along and surrounds the parts. The frame 16 is used to hold the electronic component structure 1 as shown in FIGS. 3, 1, 11, 13, and 14.
Therefore, the substrate 21, display element 34, and battery 43 of the electronic component assembly 11 are held by the frame 16 so as not to move laterally.

The upper case 1 will be described with reference to FIGS. 5 to 7 and 11 to 14. The upper case 1 is a combination of a top sheet 12 and an upper sheet 13. The top sheet 12 is a rectangular sheet made of a transparent resin sheet such as a polyester film with a thickness of about 80 μm, and as shown in FIGS.
An operating section 50 is provided at a location corresponding to the fixed contact forming section. This operation section 50 is connected to the top sheet 1
A plurality of key name printed parts 51 are printed in a grid pattern on the lower surface of the circuit board 21 in correspondence with the fixed contacts 24 of the board 21, and a thickness is printed corresponding to the lower side of each of the key name printed parts 51. It is formed by arranging a plurality of movable contacts 52 of about 15 to 30 μm and printing carbon ink or the like. A frame-shaped display window printing section 53 forming a display window is printed on the lower surface of the top sheet 12 to face the display element 34 of the electronic component structure 11, and a frame-shaped display window printing section 53 forming a battery window corresponding to the battery 43 is printed. A battery window printed portion 54 is printed. In addition, numeral 55 in the figure is a blind printing section. The upper sheet 13 is made of a material with excellent strength (toughness) such as hard vinyl chloride.
It is a rectangular sheet made of synthetic resin with a thickness of about 180μ. As shown in FIG. 7, the fixed contacts 24 of the board 21 are attached to the upper sheet 13.
A plurality of holes 56 are formed side by side to correspond to the display element 34 and the battery 43, and holes 57 and 58 are formed side by side to correspond to the display element 34 and the battery 43, respectively. Note that 59 in the figure is a hole for allowing the integrated circuit element 26, capacitor 30, and light emitting diode 33 of the substrate 21 to escape. As shown in FIGS. 11 to 14, this upper case 1 is constructed by bonding and laminating an upper sheet 13 on the underside of the upper sheet 12 via an insulating adhesive 60 with a thickness of approximately 20 μm. The upper sheet 13 provides mechanical strength to the upper sheet 12. The top sheet 13 covers the entire upper surface of the top sheet 13, and the key name printed portions 51 of the top sheet 12 correspond to the holes 56 of the top sheet 13 and are measured from above, and each movable Contact points 52... are located in each hole 56... The display window printed portion 53 and the battery window printed portion 54 of the top sheet 12 are located above the periphery of the holes 57 and 58 of the top sheet 13, and these printed portions 53 and 5
The transparent upper sheet portion surrounded by 4, that is, the display window and the battery window, covers the holes 57 and 58 so that the inside thereof can be seen through. The blind printed portion 55 of the top sheet 12 covers the entire upper side of each hole 59 of the top sheet 13. Note that the sheet 13 has movable contacts 52 on the top sheet 12 and fixed contacts 24 on the board 21.
It serves as a spacer to keep the switch operating distance apart.

The lower case 2 will be described with reference to FIGS. 8, 9, and 11 to 14. The lower case 2 is a combination of a lower sheet 14 and a lower sheet 15. The lower sheet 14 is a rectangular sheet made of synthetic resin such as polyester film with a thickness of about 80 μm, and as shown in FIG. 8, a planar blindfold printed portion 61 is printed on the upper surface. There is. The lower sheet 15 is a rectangular sheet with a thickness of about 80μ made of a synthetic resin with excellent strength (toughness) such as hard vinyl chloride.
As shown in the figure, a hole 62 is formed to allow the display element (liquid crystal panel) 34 of the electronic component structure 11 to escape. As shown in FIGS. 11 to 14, the lower case 2 is made by laminating the lower sheet 15 on the upper side of the lower sheet 14 via an insulating adhesive 60 with a thickness of about 20 μm. 14 covers the entire lower surface of the lower sheet 15, and a printing part 61 covers and hides the holes 62 of the lower sheet 15 from below.

The upper case 1 is shown in FIGS. 11 to 14.
As shown in the figure, the upper sheet 13 is bonded and laminated on the entire upper surface of the electronic component structure 11 and the frame 16 with an adhesive 60 having a thickness of about 20 μm. Lower case 2
The lower sheet 15 is bonded and laminated on the entire lower surface of the electronic component structure 11 and the frame 16 with an adhesive 60 having a thickness of about 20 μm. The upper case 1 supports and covers the substrate 21, integrated circuit element 26, capacitor 30, display element 34, and battery 43 of the electronic component assembly 11 from above. The lower case 2 includes a substrate 21 and a display element 3
4. Support the battery 43 from below and cover it. Further, the frame 16 is held tightly between the upper case 1 and the lower case 2 by adhesion while surrounding the electronic component structure 11. Here, as shown in FIG. 12, each hole 56 of the upper sheet 13 in the upper case 1 is positioned so as to surround each fixed contact 24 of the board 21 on the upper side, and each movable contact 5 of the upper sheet 12
2 are located above the fixed contacts 24 through the holes 56. key name printing section 51 of the top sheet 12;
The operating switch is composed of the movable contact 52, the hole 56 of the upper sheet 13, and the fixed contact 24 of the board 21,
Press the key name printed portion 51 of the top sheet 12 from above to move the movable contact 52 into the hole 5 of the top sheet 13.
6, it can be brought into contact with the fixed contact 24 of the push-down board 21 and turned on. As shown in FIG. 13, the display element (liquid crystal panel) 34 is inserted into the portion of the sheet 12 surrounded by the display window printed portion 53 of the top sheet 12 through the hole 57 of the top sheet 13 in the top case 1, that is, the display window. The display by the display element 34 is transmitted through the display window to the upper case 1.
Visible from the outside. As shown in FIG. 14, the battery (solar cell) 43 faces a portion of the sheet 12 surrounded by the battery window printed portion 53 of the top sheet 12, that is, the battery window, through the hole 58 of the top sheet 13. External light such as sunlight can be received from outside the upper case 1 through the window. In addition,
For example, ultraviolet curable ink 32 is applied as a spacer and adhesive between the upper surface of the display element 34 and the battery 43 and the upper sheet 12, respectively.

In this way, the electronic component structure 11
is surrounded and supported by a frame 16, and the upper case 1 in the form of a sheet is adhered and laminated on the upper side of the electronic component assembly 11 and the frame 16, and the lower side of the electronic component assembly 11 and the frame 16 is stacked. By adhering and laminating the sheet-like lower case 2 on the bottom case 2 so as to be in close contact with each other, a very thin small-sized electronic calculator having an integral sheet-like shape as a whole is constructed. This small electronic calculator consists of a top sheet 12 (80μ), adhesive 60 (20μ),
Top sheet 13 (180μ), adhesive 60 (20μ), substrate 21 (300μ), adhesive 60 (20μ), lower sheet 15 (80μ), adhesive 60 (20μ), bottom sheet 1
4 (80μ), the total thickness is 800μ
It is a very thin sheet (0.8mm). Each sheet 12, 13, 14, 15, frame 16 and substrate 2
1 has sufficient mechanical strength and elasticity to withstand bending with a radius of curvature of about 40 mm, and the small electronic calculator as a whole has excellent toughness. The display element (liquid crystal panel) 34 and battery (solar cell) 43 of the electronic component structure 11 similarly have sufficient toughness against bending with a radius of curvature of about 40 mm. In addition, the small electronic calculator has an upper surface and a lower surface composed of a top sheet 12 and a bottom sheet 14, and the top sheet 12 is used to provide an input key operation section, so the entire calculator is flat and has no uneven surfaces. There are no parts and the entire surface is flat. Furthermore, by interposing the frame 16 between the upper case 1 and the lower case 2, the electronic component structure 11 can be reliably supported from its periphery, and its strength can be increased by integrating with the upper and lower cases 1 and 2. In addition, by providing a gap close to the thickness of the electronic component structure 11 between the peripheral edges of the upper case 1 and the lower case 2 by the frame 16, the peripheral edges of each case 1 and 2 can be sealed easily and securely. can be worn.

Next, an embodiment of the method for manufacturing this small electronic calculator will be described with reference to FIGS. 16 to 25. The basic manufacturing process consists of assembling the electronic component structure 11, molding the sheets 12 to 15 and the frame 16, and then laminating the upper and lower sheets 13 and 15 in close contact with the upper and lower sides of the electronic component structure 11. At the same time, the upper and lower sheets 13,
The upper and lower sheets 12 and 14 are laminated in close contact with each other on the laminate 15, and the periphery of the obtained laminate is cut into a predetermined external shape.

The case of assembling the electronic component structure 11 will be described with reference to the process diagram of FIG. 20. Each hole 25, 29
A roll film made of glass epoxy resin or the like is prepared by continuously winding a large number of films of the substrate 21 formed with A predetermined wiring pattern is formed on the lower surface using copper foil 22, and then holes 2 of each board 21 are formed.
After an integrated circuit element (LSI) 26 is housed in the substrate 5 and the integrated circuit element 26 is wire bonded and sealed with a resin 28, the rolled film is cut into individual substrates 21. Then, the 16th
Solder 31 is applied as shown in Figure a and Figure 17a, then Figures 16b, c and 17b,
As shown in c, a capacitor 30 is placed in the hole 29 and a light emitting diode (LED) 33 is placed in the notch, and the solder 31 is melted and the capacitor 30 and the light emitting diode 33 are pressurized to fix them together. Next, a display element (liquid crystal panel) 34 and a battery (solar cell) 43 are placed adjacent to the substrate 21, and each terminal (finger lead) 41, 49 on the substrate 21 is formed to form each terminal 4.
Apply conductive adhesive 42 such as carbon ink to 1 and 49 and dry with hot air (temperature 120°C, time 4 seconds)
The terminals 41 and 49 are made semi-dry by
Thereafter, the substrate 21 is positioned and the terminals 41 and 49 are connected to the display element 34 and the terminal electrodes 40 and 4 of the battery 43.
8 Pressure bond and dry the bonded area with hot air (temperature
(120℃, 60 seconds) to completely dry and solidify. Finally, capacitor 30, light emitting diode 3
3. Apply an insulating adhesive 32, such as ultraviolet curing ink, to the terminal connection portions of the display element 34 and battery 43, and cure it by irradiating it with ultraviolet light. In addition,
Positioning holes 63 for assembly jigs are formed at predetermined positions in the substrate 21, display element 34, and battery 43, respectively.

The case of manufacturing the upper and lower sheets 12 and 14 will be described. Both sheets 12 and 14 are roll films made of, for example, polyester and have a predetermined thickness (80 μm). In the case of the top sheet 12, the roll film is fed out, and after printing the key name printing section 51, display window printing section 53, and battery window printing section 54 on each sheet 12 and applying carbon ink, Cut into a predetermined shape. The lower sheet 14 is cut by each sheet 14 after a blind printing part 61 is printed on each sheet 14 while the roll film is fed and fed. When cutting, the top sheet 12 has an external dimension larger than that of the final product, as shown by the two-dot chain line in FIGS. 5 and 6, and the bottom sheet 14 has an external dimension larger than that of the final product, as shown by the two-dot chain line in FIG. Cut. Further, during this cutting, positioning holes 63 for assembly jigs are punched out in portions of the upper sheet 12 and lower sheet 14 located outside the external dimensions of the final product. That is, the reason why each sheet 12, 14 is cut to have an outer dimension larger than that of the final product is to maintain positioning during the manufacturing process.

The case of manufacturing the upper and lower sheets 13, 15 and the frame 16 will be described. Each sheet 13, 15
A roll film in which a film made of synthetic resin, for example, hard vinyl chloride, having a thickness corresponding to the thickness of the frame 16 is wound, is prepared according to the manufacturing process of each sheet 13, 15 and the frame 16, and this roll film is The sheets 13, 15 and the frame 16 are formed by sequentially feeding out the sheets and cutting and punching them into predetermined shapes. The upper sheet 13 is cut into a larger outer size than the final product as shown by the two-dot chain line in FIG. 7, and the holes 56 to 59 are punched out. The lower sheet 15 is cut to have a larger external dimension than the final product as shown by the two-dot chain line in FIG. 9, and holes 62 are punched out. The frame 16 is cut to have an outer dimension larger than that of the final product as shown by the two-dot chain line in FIG. 10, and the inside is punched into the frame shape shown. Additionally, positioning holes 63 are formed in the upper and lower sheets 13, 15 and the frame 16 at predetermined positions in the portion that will become the final product and the outer portion of the final product, as shown in FIGS. 7, 9, and 10. Form by punching.

Furthermore, each part manufactured in this way is
It is assembled using the steps shown in the process diagram in Figure 1.
In this assembly, an assembly jig 64 shown in FIG. 22 and an assembly jig 65 shown in FIG. 23 are used, respectively. The assembly jig 64 has positioning pins 67 protruding from the upper surface of a table 66 at predetermined positions on the inner side of the external shape of the final product and at predetermined positions on the outer side. The assembly jig 65 has positioning pins 67 protruding from the upper surface of a table 66 at predetermined positions on the outside of the external shape of the final product. Note that the stand 66 has a larger external dimension than the final product, and the position of each positioning pin 67 corresponds to the positioning hole 63 formed in each component. and,
First, an insulating adhesive 60 is applied to the upper surface of the lower sheet 15, and the lower sheet 15 is positioned and held using an assembly jig 64. In this case, the positioning pins 67 of the assembly jig 64 are inserted into the positioning holes 63 of the lower sheet 15, and the lower sheet 15 is placed on the upper surface of the table 66. Next, the substrate 21 and the display element 3
4 and the assembly jig 6 into the positioning hole 63 of the battery 43.
By inserting the positioning pins 67 of No. 4, the electronic component assembly 11 is positioned and placed on the upper surface of the lower sheet 15 held on the stand 66. In this state, the electronic component structure 11 and the lower sheet 15 are pressed and heated to be pressed together. Then,
The frame 16 is positioned using the positioning holes 63 and the positioning pins 67 of the assembly jig 64 in the same manner as in the above-described operation, and is placed over the upper peripheral edge of the lower sheet 15, and the frame 16 is pressed and heated to form the lower part. sheet 1
Crimp to 5. In this case, the frame 16 will surround the electronic component structure 11. Next, an insulating adhesive 60 is applied to the lower surface of the upper sheet 13, and the upper sheet 13 is positioned using an assembly jig 64 and placed on top of the electronic component assembly 11 and the upper surface of the frame 16, and is pressed. , the upper sheet 13 is pressed onto the electronic component structure 11 and the frame 16 by applying heat. In this way, the electronic component structure 11, the upper sheet 13,
By combining and adhering the lower sheet 15 and the frame 16, a tightly laminated laminate is obtained. Second
Figure 4 shows this laminate.

Next, an adhesive 60 is applied to the upper surface of this laminate, that is, the upper surface of the upper sheet 13, and the display element 34 and battery 4 in the electronic component structure 11 are bonded together.
UV curable ink, i.e. adhesive 3, on the top surface of 3.
Apply 2. At this stage, an assembly jig 65 is used in place of the assembly jig 64. The laminate is positioned and placed on the upper surface of the stand 66 of the assembly jig 65 by passing the positioning pin 67 of the assembly jig 65 through the positioning hole 63 formed in the outer part of the final product in the laminate. . Next, top sheet 1
2 is positioned by an assembly jig 65 and placed on top of the upper surface of the upper sheet 13 in the laminate, and the upper sheet 12 is attached to the upper sheet 13 by applying pressure and heating.
Crimp. After that, UV curable ink 32 on display element 34 and battery 43 is irradiated with UV rays.
harden. Next, the laminate is turned upside down so that its vertical position is reversed, and positioned and held in the assembly jig 65 again, and the adhesive 60 is applied to the surface (lower surface) of the lower sheet 15, which is now the upper side. Next, the lower sheet 14 is positioned and held by the assembly jig 65 and placed over the surface (lower surface) of the lower sheet 15, and the lower sheet 14 is pressed onto the lower sheet 15 by pressure and heating. Through the manufacturing process up to this point, as shown in FIG. 25, the upper and lower sheets 1
A laminate is obtained in which upper and lower sheets 12 and 14 are closely laminated on sheets 3 and 15. That is, it is a laminate in which the electronic component structure 11, the frame 16, the upper case 1, and the lower case 2 are laminated together.

Further, a portion of this laminate on the outer circumferential side that is larger than the outer shape of the final product is cut and formed into the outer shape of the final product shown in FIG. Top sheet 1
2. The upper sheet 13, the lower sheet 14, the lower sheet 15, and the frame 16 are formed to have a larger outer shape than the final product, and the excess outer peripheral portion is cut off. That is, the outer circumferential portion of the laminate where the frame 16 surrounding the electronic component structure 11 is interposed is cut out to give the final product shape.

In this way, as shown in FIG. 2, a sheet-shaped compact electronic calculator is manufactured in which the electronic component structure 11, the upper case 1, and the lower case 2 are laminated.

In this way, this small electronic calculator stores electronic components in the electronic component storage areas provided in the upper case and the lower case, and the upper case, the electronic components, and the lower case are bonded together with adhesive. Since it is a structure in which the upper case, electronic component components, and lower case are bonded together by laminating and bonding, it is possible to reduce the thickness to less than 1 mm, making it possible to significantly reduce the thickness. At the same time, sufficient mechanical strength can be provided. In addition, since screws are not used to connect each case and the electronic component components, the cases will not be damaged even if the walls of each case are made thinner and connected. can. Furthermore, each case and the electronic component structure can be easily assembled by adhering them to each other.

Therefore, in the small electronic device of the present invention, a sheet-like upper case and a sheet-like lower case are closely stacked on the upper and lower sides of an electronic component structure, and the electronic component structure is further surrounded by a frame between the two cases. The configuration is such that it is supported. The upper case has a switch operation section and a display window, and is in the form of a sheet that is tightly laminated on the upper side of the electronic component structure.
The lower case is in the form of a sheet that is closely laminated under the electronic component structure.

The upper case and lower case will be explained using a small electronic calculator as an example. In the above-described embodiment, the upper case 1 is constructed by combining the upper sheet 12 with the upper sheet 13 as a reinforcing and switch spacer as an integral structure, but the upper case has the basic functions described above. By making the upper sheet 13 into an integral structure, the upper case 1 can be constructed only from the upper sheet 12 having the display window printing section (display window) 53 and the operation section 50. When the top sheet 12 is used as the upper case 1, a spacer for the switch may be provided on the lower side of the top sheet 12 corresponding to the operation section 50, and in this case, the lower case 2 and the frame 16 are It is preferably made of thick and hard resin to make it durable. FIG. 26 shows an example of this case, and 68 in the figure is a spacer.
Furthermore, instead of making the top sheet 12 thin as in the above-mentioned embodiments, the top sheet 12 can be made thick from hard vinyl chloride like the top sheet 13 to increase its own strength and be used alone as the top case 1. I can do it. FIG. 27 shows an example. In this case, the operation section of the upper sheet 13 may be made thinner only in that portion so that it can be operated by pressing, and a spacer 68 may be provided on the lower side. In short, the upper case 1 basically only needs to be a single sheet having an operating section and a display window, and can also have a multilayer structure. The configuration of the operating section is also not limited to the embodiment. Further, in the above-described embodiment, the lower case 2 has a structure in which the lower sheet 14 and the lower sheet 15 are integrally laminated and combined, but the lower case 2 is laminated below the electronic component structure 11. Therefore, it is also possible to use only one of the lower sheet 14 and the lower sheet 15 as the lower case 2 without combining the two sheets 14 and 15 together. For example, as shown in FIGS. 26 and 27, the lower sheet 15 can be used alone as the lower sheet 2. Further, although not shown, only the lower sheet 14 can be used as the lower case 2. In this way, the upper case 1 and the lower case 2 can have a structure in which individual sheets are closely laminated on the upper and lower sides of the electronic component structure 11 and the frame 16, respectively.

Let's talk about the frame. The frame is located between the upper case and the lower case, and its basic structure is to surround and support the electronic component structure.
The above-mentioned embodiment and FIGS. 26 and 27
In the illustrated example, the frame 16 is formed separately from the upper case 1 and the lower case 2, and the independent frame 16 is interposed between the peripheral edges of the upper case 1 and the lower case 2. Although they are in close contact with each other, the present invention is not limited to this configuration, and it is also possible to have a structure in which a frame is integrally formed on one or both of the upper case and the lower case, and the upper case and the lower case are brought into close contact with each other through a frame 16 that is integrally formed with the case. You can also.
FIGS. 28 and 29 show an embodiment in which the frame 16 is integrally formed with the case. In addition,
In this embodiment, the upper case 1 and the lower case 2 are
For example, it is composed of a thick single sheet made of hard vinyl chloride. In this embodiment, a frame 16 having the same shape as the frame 16 described above is integrally formed at the peripheral edge of the lower case 2. The electronic component structure 11 is arranged in a recess surrounded by the frame 16 of the lower case 2, and the upper case 1 is arranged in a recess surrounded by the frame 16 of the lower case 2.
1 and the upper side of the frame 16 in close contact with each other.

Furthermore, the electronic component structure 11 is, for example, a substrate 21.
is not limited to the example, but may be divided into two pieces and electrically connected to each other as shown in FIG. make up the body.

Note that the present invention is not limited to small electronic calculators, but can be widely applied to small sheet-shaped electronic devices.

〔Effect of the invention〕

As explained above, according to the small electronic device of the present invention, the integrated circuit element is arranged in the opening formed in the wiring board, and the outer periphery of each component of the electronic component assembly in which the display element is arranged on the side of the wiring board. is held by a frame thinner than the display element, and further laminated and adhered to the upper sheet-like upper case of the electronic component structure, and a lower case having a recessed part for the display element is laminated and adhered to the lower side of the electronic component structure. By reducing the wall thickness of the case, the upper and lower cases can be joined together without damaging the case as with the conventional screw-fastening method, and the case is thinner because the case and electronic components are bonded to each other. It is possible to achieve this and improve the strength. Therefore, it is possible to significantly reduce the thickness of the device to, for example, 1 mm or less, and to make it thin enough to be used as a credit card.

[Brief explanation of drawings]

1 to 19 show an embodiment of a small electronic calculator to which the present invention is applied, FIG. 1 is an exploded perspective view of the small electronic calculator, FIG. 2 is a perspective view showing the external appearance, Fig. 3 is a plan view showing the electronic component structure, Fig. 4 is an exploded perspective view, Fig. 5 is a top plan view of the top sheet, Fig. 6 is a bottom plan view of the top sheet, and Fig. 7 is a top plan view of the top sheet. 8 is a plan view of the lower sheet, FIG. 9 is a plan view of the lower sheet, FIG. 10 is a plan view of the frame, and FIGS.
Fig. 4 is an enlarged cross-sectional view of a portion of a small electronic calculator, Fig. 15 is an enlarged cross-sectional view of a mounting portion between an integrated circuit element and a board, and Fig. 16 a, b, c.
17A, 17B and 17C are sectional views respectively showing the case where a chip capacitor is attached to a substrate, and FIGS. 18A and 18B are sectional views respectively showing a case where a light emitting diode is attached to a substrate. FIGS. 19a and 19b are cross-sectional views showing the case where the battery is attached to the board, and FIGS. 20 to 25 are cross-sectional views showing the case of manufacturing a small electronic calculator. , FIG. 20 is a process explanatory diagram showing the assembly process of the electronic component structure, FIG. 21 is a process explanatory diagram showing the entire assembly process, and FIGS.
3 is a perspective view showing an assembly jig, FIGS. 24 and 25 are perspective views showing an intermediate assembled product, and FIGS. 26 and 27 are cross sections showing other embodiments of the small electronic calculator. Figures 28 and 29
The figures are a sectional view and a perspective view showing other embodiments of the structure of the frame, respectively, and FIG. 30 is an exploded perspective view showing another embodiment of the electronic component structure. DESCRIPTION OF SYMBOLS 1... Upper case, 2... Lower case, 11... Electronic component structure, 12... Upper sheet, 13... Upper sheet, 14... Lower sheet, 15... Lower sheet, 16
...Frame, 21...Substrate, 22...Copper foil, 24...Fixed contact, 26...Integrated circuit element, 30...Capacitor, 3
3...Light emitting diode, 34...Display element (liquid crystal panel), 43...Battery (solar cell), 50...Operation unit, 5
DESCRIPTION OF SYMBOLS 1...Key name printing part, 52...Movable contact, 53...Display window printing part, 54...Battery window printing part, 57-59...
Hole portion, 61... Calibration printing portion, 62... Hole portion, 63...
Positioning hole, 64, 65...assembly jig, 66...stand,
67...Positioning pin, 68...Spacer.

Claims (1)

[Scope of Claims] 1. A wiring board on which a predetermined wiring pattern including key contacts is formed and an opening larger than the outer shape of a semiconductor integrated circuit element, and a semiconductor placed in the opening and connected to the wiring board. integrated circuit elements,
and an electronic component structure having a display element and a battery arranged side by side on the wiring board and firmly bonded to the wiring board with a conductive adhesive; and the wiring board constituting the electronic component structure.
A frame formed to surround the outer periphery of the display element and the battery and formed thinner than the thickness of the display element, a key display portion facing the key contact, and a see-through window of the display element. and a sheet-like upper case laminated in close contact with the upper side of the electronic component structure and bonded to the upper surface of the frame, and a display element recessed part facing the display element, A small electronic device comprising: a lower case laminated in close contact with the lower side of a component structure; 2. The small electronic device according to claim 1, wherein the frame is formed as a frame member separate from the case member. 3. The small-sized power-on device according to claim 1, wherein the frame is a frame portion integrally formed with the lower case.