JPH024022B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing small electronic equipment.

[Conventional technology]

In the case of small electronic devices such as small electronic computers, an upper case and a lower case, which are molded products of synthetic resin, are combined, and electronic components such as circuit boards and semiconductor integrated circuits are housed inside the case. A configuration is adopted in which the upper case and lower case are joined by passing screws through screw holes formed in the upper case and tightening the screw holes.

[Problem that the invention seeks to solve]

By the way, in recent years, small electronic devices such as small computers have been becoming thinner in order to improve their portability. The goal is to do so.

However, in the past, screws were passed through screw holes formed in the upper and lower cases of synthetic resin molded products, and the screws were tightened to connect both cases. If the wall thickness of the case and the lower case is made thinner, the screw hole portion of each case becomes thinner, and when a screw is passed through the screw hole and tightened, there is a risk that the case may be damaged from the screw hole portion due to the tightening force. For this reason, there is a problem in that it is difficult to make the device case of a small electronic device as thin as a credit card while maintaining its strength.

The present invention was made based on the above circumstances, and
An object of the present invention is to provide a method for manufacturing a small electronic device, which can ensure sufficient mechanical strength while achieving a large thickness reduction, and can obtain a small electronic device with an accurate and clean external shape.

[Means for solving problems]

In order to achieve the above object, the method for manufacturing a small electronic device of the present invention includes the following steps: preparing a wiring board on which a predetermined wiring pattern is formed; connecting a semiconductor integrated circuit element to the wiring board; and connecting the wiring to the wiring board. a step of connecting an electronic component such as a display element to a substrate; and a step of connecting an electronic component such as a display element to a substrate; a first adhesion step in which a first case having a large size is bonded to cover one entire surface of the electronic component structure with the first case; and after the first bonding step, the other surface of the electronic component structure is a second adhering step of gluing a second case having external dimensions larger than the electronic component structure to cover the entire other surface of the electronic component structure with the second case; and the first case. and a step of cutting the second case outside the outer periphery of the electronic component structure.

[Effect]

According to this method, the upper case and lower case are bonded with adhesive without providing screw holes in the case, so it is possible to make the upper case and lower case thinner while ensuring their strength. By cutting the outer periphery of the case, which has an outer dimension larger than that of the finished product, after gluing the parts, the case can be easily aligned and the outer shape of the case can be finished neatly.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the manufacturing method of the present invention is applied to a case where a small electronic calculator is manufactured.

First, the configuration of an electronic calculator manufactured by the manufacturing method of this embodiment will be explained with reference to FIGS. 2 to 20.

FIG. 2 is an external view of the small electronic calculator of this embodiment. As shown in this figure, the small electronic calculator has a rectangular sheet shape. FIG. 3 is an exploded view of a small electronic calculator, in which 11 is an electronic component component, 12 is a top sheet, 13 is an upper sheet,
14 is a bottom sheet, 15 is a lower sheet, and 16 is a frame. Each of these sheets 12, 13, 14, 15
The frame 16 and the frame 16 each have a rectangular outer shape with the same size. The upper sheet 12 and the upper sheet 13 are laminated in close contact with each other to constitute the upper case 1 in the form of a sheet, and the lower sheet 14 and the lower sheet 15 are in close contact with each other to constitute the lower case 2 in the form of a sheet. are doing. Then, the electronic component structure 11 is surrounded and supported by the frame 16, and the upper case 1 is laminated in close contact with the upper side of the electronic component structure 11 and the frame 6. A lower case 2 is laminated in close contact with the lower side. 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. 4 to 20. 4 to 11 are plan views showing each component. 12 to 15 are cross-sectional views showing the laminated structure,
Figure 12 shows the boundary between the board and the frame (part A in Figure 2),
Figure 13 shows the part where the operation switch is installed (Figure 2B
part), Figure 14 shows the part where the display element is installed (part C in Figure 2), and Figure 15 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 will be described with reference to FIG. 4 and FIGS. 14 to 20. As shown in FIG. 4, the substrate 21 is made of glass epoxy resin or bismaleide-triazine resin and is in the form of a rectangular sheet with a thickness of about 190 μm, and its upper and lower surfaces are thick enough to form a predetermined wiring pattern. Copper foil 22 with a diameter of about 35μ
are 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 FIG. 4, and connects fixed contacts, capacitors, display elements, batteries, light emitting diodes, etc. around the integrated circuit element. On one half of the upper surface of the substrate 21, a plurality of fixed contacts 24, which are part of the wiring pattern and are switch elements, are arranged in a grid pattern.The fixed contacts 24 consist of a pair of contacts, and each contact is connected to an integrated circuit element 26, which will be described later, via a wiring pattern. As shown in FIG. 16, 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 side, and a predetermined calculation is performed by turning on and off the switch element. A semiconductor integrated circuit element 26, that is, a large-scale integrated circuit (LSI) that performs foil 2
2), and is covered from above with an insulating resin 28 such as silicone rubber or epoxy resin to seal the entire body. 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 insulating resin 28 is, for example, 10 mm long x 10 mm wide x thickness from the top surface of the integrated circuit.
It has a diameter of 245μ. 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 bottom side, a chip capacitor 30 is placed on the bottom side, as shown in FIG. 17c. The capacitor 30 is supported by the wiring pattern (copper foil 2
2), and its surroundings are covered with an insulating adhesive 32, such as ultraviolet curing ink, applied to the upper surface of the substrate 21. 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 this part is supported by the wiring pattern on the bottom side as shown in FIG. 18c. A light emitting diode 33 for power supply voltage control is arranged, and the electrode 33a of this light emitting diode 33 is bonded to cream solder 31 applied to the board 21 and connected to the wiring pattern (copper foil 22) on the upper surface side of the board 21. The periphery of the substrate 21 is sealed with an insulating adhesive 32 applied to the upper surface of the substrate 21, such as ultraviolet curable ink. 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. As shown in FIG. 19, the display element (liquid crystal panel) 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. The periphery of the electrode base 36 is sealed with a seal 38, and a reflecting plate 39 with a thickness of about 50 μm is bonded to the lower surface of the lower electrode base 36 with an adhesive having a thickness of about 15 μm. A plurality of terminal electrodes 40 made of transparent conductive ink are formed in the longitudinal direction on the upper surface of the protrusion of the lower electrode base 36 and connected to the electrodes of the respective electrode bases 35 and 36. 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, on one side edge 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, and displays predetermined information based on a signal from the integrated circuit element 26. A display element 3 is provided on one side edge of the substrate 21.
A battery 43 , for example a solar battery, for supplying a driving voltage to the integrated circuit element 26 is arranged alongside 4 and is connected to the wiring pattern of the substrate 21 . As shown in FIG. 20, a battery (solar cell) 43 has a thickness of 25 μm on the upper surface of a metal substrate 44 made of stainless steel or the like.
An amorphous solar cell layer 46 is deposited via an insulating layer 45 of, for example, polyimide, and a polyester film 47 with a thickness of about 175 μm is further coated on the solar cell layer 16 as a protective layer.
A pair of terminal electrodes 4 are placed on the top surface of 4 with an insulating layer 45 interposed therebetween.
8,48. This cell (solar cell) 43 has a total thickness of about 300 μm and has elasticity (toughness) as a whole. Also, the board 2
A pair of terminals 49, 49 are formed on one side edge of the battery 1, facing a battery (solar cell) 43, with a copper foil 22 of a wiring pattern protruding laterally. The terminal electrodes 48 of the battery (solar cell) 43 and the terminals 49 of the substrate 21 are electrically connected by applying a conductive adhesive 42, for example, carbon ink, and adhering them to each other, and the surroundings are insulating adhesive. The agent 32 is coated with, for example, ultraviolet curable ink.
Therefore, the battery (solar cell) 43 is 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 is made of, for example, hard vinyl chloride and has a thickness of about 300 μm, and has a rectangular frame shape as shown in FIG. Depending on the arrangement, it has a shape that runs along and surrounds the periphery of the component. As shown in FIGS. 4, 12, 14, and 15, the frame 16 is arranged around the electronic component structure 11, so that the board 21 of the electronic component structure
The display element 34 and the battery 43 are held by the frame 16 so as not to move laterally.

The upper case 1 will be described with reference to FIGS. 6 to 8 and 12 to 15. 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 FIG. 6 and FIG.
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 printing 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. 8, the upper sheet 13 has fixed contacts 24 of the board 21...
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. 12 to 15, 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 about 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 are in the respective holes 56 of the top sheet 13.
The movable contacts 52 are located in the respective holes 56. The display window print part 53 and the battery window print part 54 of the top sheet 12 are located above the periphery of the holes 57 and 58 of the top sheet 13 to hide them, and the transparent top sheet part surrounded by these print parts 53 and 54 That is, the display window and the battery window cover 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. The upper sheet 13 serves as a spacer that separates the movable contact 52 of the upper sheet 12 from the fixed contact 24 of the substrate 21 and maintains the switch operation interval.

The lower case 2 is shown in FIGS. 9, 10, and 12.
Figures 1 to 15 will be described. 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 approximately 80 μm, and as shown in FIG. 9, 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 80 μm made of a synthetic resin with excellent strength (toughness) such as hard vinyl chloride, and as shown in FIG. A hole 62 is formed to allow the liquid crystal panel 34 to escape. And the lower case 2 is the 12th
As shown in FIGS. 15 to 15, a lower sheet 15 is laminated on the upper side of a lower sheet 14 through an insulating adhesive 60 having a thickness of about 20 μm, and the lower sheet 14 is formed on the entire lower surface of the lower sheet 15. A blindfold printing part 61 covers and hides the hole part 62 of the lower sheet 15 from below.

The upper case 1 is shown in FIGS. 12 to 15.
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 while surrounding the electronic component structure 11. Here, as shown in FIG. 13, 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 52 of the upper sheet 12 is positioned so as to surround each fixed contact 24 of the board 21 on the upper side. are located above the fixed contacts 24 through the holes 56. Key name printing section 51 on top sheet 12, movable contact 5
2. An operation switch is constructed by the hole 56 of the upper sheet 13 and the fixed contact 24 of the board 21, and the key name printed part 51 of the upper sheet 12 is pressed from above to move the movable contact 52 through the hole 56 of the upper sheet 13. It can be brought into contact with the fixed contact 24 of the push-down board 21 through the push-down board 21 and turned on. As shown in FIG.
The portion of the sheet 12 surrounded by the display window printed portion 53 of No. 2, that is, faces the display window, and the display by the display element 34 can be visually recognized from the outside of the upper case 1 through the display window. As shown in FIG. 14, the battery (solar cell) 43 faces the battery window printed portion 53 of the top sheet 12 through the hole 58 of the top sheet 13, and faces the enclosed portion of the sheet 12, that is, the battery window. External light such as sunlight can be received from outside the upper case 1 through the window. Note that the display element 3
4 and the battery 43, for example, an ultraviolet curable ink 32 is applied as a spacer and adhesive between the upper surfaces of the batteries 43 and the upper sheet 12, respectively.

In this way, the electronic component structure 11
is surrounded and supported by a frame 16, and a sheet-like upper case 1 is laminated in close contact with the upper side of the electronic component assembly 11 and the frame 16, and the electronic component assembly 11 and the frame 16 are stacked closely together.
By closely stacking the sheet-shaped lower case 2 on the lower side of the computer, a compact electronic calculator having an integral sheet-like shape is constructed. This small electronic calculator has a top sheet of 12 (80μ) and an adhesive of 60
(20μ), top sheet 13 (180μ), adhesive 60
(20μ), substrate 21 (300μ), adhesive 60 (20μ),
The combination of the lower sheet 15 (80μ), the adhesive 60 (20μ), and the lower sheet 14 (80μ) forms a very thin sheet with a total thickness of 800μ (0.8mm). Each sheet 12, 13, 14, 15 and frame 16
The substrate 21 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. Display element (liquid crystal panel) 34 of electronic component structure 11, battery (solar cell)
43 also has sufficient toughness for bending with a radius of curvature of about 4 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. In addition, by interposing the frame 16 between the upper case 1 and the lower case 2, the electronic component structure 11 is reliably supported from its periphery, and the upper and lower cases 1,
In addition, the frame 16 provides 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, so that each case 1, The peripheral edges of the parts 2 and 2 can be sealed together easily and reliably.

Next, an embodiment of manufacturing a small electronic calculator having such a configuration by the manufacturing method of the present invention will be described with reference to FIG. 1 and FIGS. 21 to 25. The basic manufacturing process involves assembling the electronic component structure 11, forming 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. 21. 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 bonding an integrated circuit element (LSI) 26 to the substrate 5 and performing wire bonding and sealing with a resin 28, the rolled film is cut into individual substrates 21. Then, solder 31 is applied to the holes 29 and notches of the cut substrate 21 as shown in FIGS. 17a and 18a, and then as shown in FIGS.
As shown in Figure 8 b and c, the capacitor 30 is inserted into the hole 2.
9, light emitting diodes (LEDs) 33 are placed in the notches, and the solder 31 is melted and the capacitor 30 and the light emitting diodes 33 are pressurized to fix them together. Next, a display element (liquid crystal panel) 34 and a battery (solar cell) are placed adjacent to the substrate 21.
43 and forming each terminal (finger lead) 41, 49 on the board 21,
A conductive adhesive 42, for example, carbon ink, is applied to each terminal 41, 49, and the terminals 41, 49 are semi-dried by hot air drying (temperature 120°C, time 4 seconds).Then, the board 21 is positioned and the terminals 4
1 and 49 are bonded under pressure to the display element 34 and the terminal electrodes 40 and 48 of the battery 43, and the bonded portions are completely dried and fixed by hot air drying (temperature: 120° C., time: 60 seconds). Finally, an insulating adhesive 32 such as an ultraviolet curable ink is applied to the terminal connection portions of the capacitor 30, light emitting diode 33, display element 34, and battery 43, and is cured by irradiating ultraviolet rays. Note that the substrate 21, display element 34, and battery 4
3 has positioning holes 6 for assembly jigs at predetermined positions, respectively.
form 3.

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 specified shape. The lower sheet 14 is cut by each sheet 14 after a blind printing portion 61 is printed on each sheet 14 while the roll film is fed and fed. When cutting, the top sheet 12 has external dimensions larger than the external dimensions of the final product, as shown by the two-dot chain line in FIGS. 6 and 7, and the bottom sheet 14, as shown by the two-dot chain line in FIG. 9. Cut. Further, during this cutting, positioning holes 63 for assembly jigs are punched out in portions of the top sheet 12 and bottom 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 and 15 and the frame 16 are formed by sequentially feeding out the sheets and cutting and punching them into a predetermined shape. The upper sheet 13 is cut into a larger external dimension than the final product as shown by the two-dot chain line in FIG. 8, and 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. 10, 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. 11, 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, respectively, as shown in FIGS. 8, 10, and 11. Form by punching.

Furthermore, each part manufactured in this way is
It is assembled using the steps shown in the process explanatory diagram in Figure 2.
Incidentally, during this assembly, an assembly jig 64 shown in FIG. 23 and an assembly jig 65 shown in FIG. 24 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 aligned with the positioning holes 63 of the lower sheet 15 and inserted, and the lower sheet 15 is placed on the upper surface of the stand 66. Next, the substrate 21 and the display element 34
and an assembly jig 64 in the positioning hole 63 of the battery 43.
By inserting the positioning pin 67 , the electronic component structure 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,
A laminate is obtained in which the lower sheet 15 and the frame 16 are combined and laminated in close contact. FIG. 25 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 surface of the top sheet 13 in the laminate, and the top sheet 12 is attached to the top 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. 1, the upper and lower sheets 13,
A laminate is obtained in which the upper and lower sheets 12 and 14 are laminated in close contact with each other. 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.

By this method, as shown in Fig. 2, a small electronic calculator in the form of a sheet is manufactured, in which the electronic component structure 11 is surrounded and supported by a frame 16, and the upper case 1 and the lower case 2 are laminated on the upper and lower sides of the frame 16. do.

According to this method, the electronic component structure 1
By bonding the upper case 1 and the lower case 2 that housed the case 1 and the lower case 2 through the frame 16 with the adhesive 60, the upper case 1 and the lower case 2 can be connected without using screws, and the flesh of the case is Even if the cases are combined with a reduced thickness, the cases will not be damaged, and the wall thickness of each of the cases 1 and 2 can be reduced. Therefore, the combined thickness of the upper case 1 and the lower case 2 can be kept to 1 mm or less, thereby making the case thinner and providing the case with sufficient mechanical strength. Further, in this embodiment, the electronic component 11 is also bonded to the upper case and the lower case 2 with adhesive, so that the overall strength of the small electronic calculator can be further increased.

Further, the upper case 1, the lower case 2, and the frame 16 were formed in advance to have a larger external size and shape than the final product, and the upper case 1, the lower case 2, the frame 16, and the electronic component structure 11 were bonded together. After forming the laminate, the excess outer circumferential portions of the upper case 1, lower case 2, and frame 16 are cut to form the final product into the external dimensions and shape.
When assembling the case, the upper case 1, the lower case 2, and the frame 16 can be aligned dimensionally gently, making the assembly work easy, and the external dimensions and shape of the final product can be finished accurately and neatly. Can be done.

Therefore, in a small electronic device manufactured by the manufacturing method of the present invention, a sheet-like upper case and a sheet-like lower case are tightly laminated on the upper and lower sides of an electronic component structure, and a frame is provided between the two cases to form an electronic component. The structure is designed to surround and support the structure. 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, and the lower case is in the form of a sheet that is tightly laminated on the lower side of the electronic component structure. It is something that does.

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. , the upper sheet 13 is made into an integral structure, and the upper case 1 is constructed only with the upper sheet 12 having the display window printing section (display window) 53 and the operation section 50 without being combined.
can be configured. 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. Can be done. FIG. 27 shows an example. In this case, the operation section of the upper sheet 12 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 is attached to the lower case 2 by itself.
It can be used as Further, although not shown, only the lower sheet 14 can be used as the lower case 2. In this way, as the upper case 1 and the lower case 2, the electronic component structure 11 and the frame 1
It is possible to have a structure in which single sheets are laminated in close contact with each other on the upper and lower sides of 6.

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 embodiments 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. The battery is not limited to a solar cell, and a normal button-type battery may be used alone or in combination with a solar cell.

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

〔Effect of the invention〕

As explained above, according to the method for manufacturing a small electronic device of the present invention, it is possible to obtain a thin small electronic device having a case that is thin yet has sufficient strength, and furthermore, it is possible to obtain a thin small electronic device that has a case that is thin but has sufficient strength. The process is easy and has good productivity, and the external dimensions and shapes of the final product, small electronic devices, can be finished accurately and neatly.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a laminate manufactured by an embodiment of the manufacturing method of the present invention, and FIG.
Fig. 0 shows an embodiment of a small electronic calculator manufactured by the manufacturing method of the present invention, Fig. 2 is a perspective view showing the external appearance of the small electronic calculator, Fig. 3 is an exploded perspective view, and Fig. 4. is a plan view showing an electronic component configuration,
Fig. 5 is an exploded perspective view, Fig. 6 is a top plan view of the top sheet, Fig. 7 is a bottom plan view of the top sheet, Fig. 8 is a plan view of the top sheet, and Fig. 9 is a plan view of the bottom sheet. , Fig. 10 is a plan view of the lower sheet, Fig. 11 is a plan view of the frame, Figs. 12 to 15 are partial cross-sectional views of the small electronic calculator, and Fig. 16 is the attachment of the integrated circuit element to the board. Figures 17a, b, and c are sectional views showing the case in which a chip capacitor is attached to a substrate, and Figures 18a, b, and c are sectional views each showing a case in which a light emitting diode is attached to a substrate. , FIGS. 19a and 19b are cross-sectional views showing the case where the display element is attached to the substrate, FIGS. 20 a and b are cross-sectional views respectively showing the case where the battery is attached to the substrate, and FIGS. 21 is a process explanatory diagram showing the assembly process of electronic component components, and FIG. 22 is a process explanatory diagram showing the entire assembly process. 23 and 24 are respectively perspective views showing an assembly jig, FIG. 25 is a perspective view showing an intermediate assembled product, and FIGS. 26 and 27 are respectively showing other embodiments of the small electronic calculator. Cross-sectional view shown, second
8 and 29 are sectional views and perspective views 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... Blindfold printing portion, 62... Hole portion, 63...
Positioning hole, 64, 65...assembly jig, 66...stand,
67...Positioning pin, 68...Spacer.

Claims (1)

[Claims] 1. A step of preparing a wiring board on which a predetermined wiring pattern is formed, a step of connecting a semiconductor integrated circuit element to the wiring board, and a step of connecting an electronic component such as a display element to the wiring board. a step of: adhering a first case having external dimensions larger than the electronic component component to one surface of the electronic component component to which electronic components such as the wiring board, the integrated circuit element, and the display element are connected; a first bonding step in which the entire surface of the electronic component structure is covered by the first case; and after the first bonding step, an external dimension larger than that of the electronic component structure is formed on the other surface of the electronic component structure. a second adhering step of bonding a second case with a larger diameter to cover the entire other surface of the electronic component structure with the second case; A method of manufacturing a small electronic device, comprising: a step of cutting outside the outer periphery of the body.