JP2000285762A - Control panel equipped with molded-sheet push bottom unit and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve hermeticity, clearness, and operability, and realize cost reduction. SOLUTION: A commercially available, light-transmitting simple-substance sheet made of a thermoplastic synthetic resin is used as a substrate, and a molded sheet is made by forming recessed sheet parts 14 in the simple-substance sheet, so that a print layer 11 formed on a surface thereof is positioned inside bottom surface of each recessed sheet part 14. A key sheet 24 equipped with push buttons 4 is made by filling the recessed parts with synthetic resin, The key sheet 24 is heat-welded by ultrasonic wave to a back surface of a case cover 3 to make the two into an integral unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control panel having a sheet forming push button unit formed by forming a general-purpose sheet and a method of manufacturing the same. More specifically, the present invention relates to a control panel provided with a sheet forming push button unit made of a molded sheet formed by thermoforming a thermoplastic synthetic resin sheet, and a method of manufacturing the same.

[0002]

2. Description of the Related Art With the spread of computer-related equipment and communication equipment in recent years, an input operation unit such as a control panel for inputting and outputting information to and from these equipment has been provided without sacrifice of operability and at extremely low cost. Has been requested. On the other hand, in addition to increasing the precision of electronic components, hermeticity is required to prevent dust and destruction of electronic components due to static electricity. For example, control panels for components used in electronic devices such as portable telephones require ultimate cost reduction in order to spread these devices at low cost. Improvements in various functions are also required.

The applicant of the present invention has proposed a control panel for electronic equipment using a sheet for this purpose (Japanese Patent Laid-Open No. 9-2596).
96, JP-A-9-259697). The proposed device employs a mechanical assembly structure for assembling the control panel and the push buttons. When this mechanical assembly structure is employed, the structure becomes complicated and the number of parts increases.

[0004]

SUMMARY OF THE INVENTION The present invention has been made based on such a technical background and achieves the following objects. SUMMARY OF THE INVENTION It is an object of the present invention to provide a control panel having a sheet forming push button unit and a method of manufacturing the same, in which a formed sheet manufactured by thermoforming a sheet is integrated with a control panel to reduce the number of steps. is there. Another object of the present invention is to provide a control panel having a sheet forming push button unit which can be reduced in cost, and a method of manufacturing the control panel. It is still another object of the present invention to provide a control panel having a sheet forming push button unit excellent in mass productivity and a method of manufacturing the same.

[0005]

Means for Solving the Problems To solve the above-mentioned problems, the following means are adopted. The control panel provided with the first sheet forming push button unit of the present invention includes a push button (4) inserted into an opening (8) of a control panel (3) such as an electronic device, and the control panel (3). , And elastically flexibly supports the push button on the control panel (3);
And a molded sheet (23) molded to be the outer skin of the push button.

The molded sheet (23) and the control panel (3) are preferably fixed integrally by thermal bonding. Thermal bonding means that both members are connected and fixed by heating from inside or outside of a thermoplastic synthetic resin. Specifically, there is a method of pressing and deforming a heated member and caulking, and ultrasonic welding by ultrasonic vibration energy.

The control panel provided with the second sheet forming push button unit of the present invention includes a push button body (4) inserted into an opening (8) of a control panel (3) of an electronic device or the like.
5) fixed to the control panel (3), elastically flexing and supporting the push button body (45) to the control panel (3), and the push button body (45) is fixed and formed. Formed sheet (42). The molded sheet and the control panel (3) may be integrally fixed by thermal bonding. The term “thermal bonding” has the same meaning as described above.

A method for manufacturing a control panel having a first sheet forming push button unit according to the present invention is made by the following steps. That is, a plurality of recesses serving as outer skins of a push button are formed in the single sheet (10) by thermoforming to form a formed sheet (2).
3), the molded sheet (23) is inserted into an injection mold (20, 25), and the concave portion is filled with a molten resin to form a key sheet (24).
Are integrally fixed to the control panel (3) by thermal bonding.

A method for manufacturing a control panel having a second sheet forming push button unit according to the present invention is made by the following steps. That is, a molded sheet (42) is formed on the single sheet (10) by thermoforming, and the molded sheet (42) is fixed to the push button body (45) and the control panel (3) by thermal bonding. . The term “thermal bonding” has the same meaning as described above.

[0010]

Embodiments of the present invention will be described below. [Embodiment 1] An example in which a control panel of an electronic device of the present invention is applied to a portable telephone will be described. The one shown in FIG.
1 is a perspective view of a portable telephone provided with a control panel of the present invention. The portable telephone 1 is composed of a telephone main body 2 made of a synthetic resin, and electronic equipment such as an IC for realizing the function of the telephone is installed in the telephone main body 2.

The telephone body 2 is composed of two bodies and is divided into two parts by a dividing surface 6 at the center of the thickness. A case cover 3 is arranged on the upper surface of the telephone main body 2, and a back body 5 is disposed on the rear surface thereof.
Is arranged. The case cover 3 performs both the function of the control panel and the function of the telephone main body 2, and a plurality of push buttons 4 are arranged to form a key group 7.
The case cover 3 and the back surface main body 5 are integrally fixed by fixing means such as screws or notches.

(Printing of Display Unit) In the case cover 3,
A push button 4 described later is provided. Hereinafter, this manufacturing method will be described in detail. As the outer skin of the push button 4, a single sheet 10 which is a uniform sheet as shown in the plan view of FIG. 2 is used. The single sheet 10 has a thickness of, for example, 0.2
It is a transparent or translucent body of about 5 mm to 0.8 mm, that is, a thin film-shaped thermoplastic synthetic resin cut into a light-transmitting rectangular shape. Specifically, polycarbonate (PC), a mixture of polybutylene terephthalate (PBT) and PC, polyethylene terephthalate (PET), PBT, AB
It is preferable to use a resin such as S resin or polyurethane (PUR).
The single sheet 10 is desirably a general-purpose product which has a high tensile strength, is hardly broken, is mass-produced by many manufacturers, and is commercially available at extremely low cost.

A plurality of numbers,
A display unit 13 for characters, symbols, and the like is arranged. Display 1
3 is printed from the back surface to form a print layer 11. As shown in FIG. 3A, in a state in which each print layer 11 of the single sheet 10 is on the upper surface (on the illustration), a necessary display unit 13 is printed at a position on the back surface of the finger contact unit 9 and the print layer 11 is printed.
And However, the printed layer 11 may be printed as a ground color on the entire surface of the single sheet 10 by removing only the display portion 13 for numbers, characters, symbols, or the like, or may be multicolored. Since the single sheet 10 is a transparent material, the display section 13 can be displayed from the back surface in the color of the synthetic resin material.

The printing of the printing layer 11 is performed by a known printing means such as silk printing. Since the single sheet 10 is a flat plate, there is an advantage that printing on this surface can be easily performed without requiring any special device. Positioning holes 12 are arranged at upper and lower positions of the single sheet 10. In order to use a portion corresponding to each printing layer 11 of the single sheet 10 as a key group, when the back surface side of each printing layer 11 is formed as a push button 4, it is formed by thermoforming described later so as to become a finger contact portion 9. It is thermoformed into a shape.

(Thermoforming) Next, a description will be given of a molding procedure in the case where the key sheet is molded by pressure forming (pressure molding). FIGS. 3A to 3D are explanatory diagrams of a process of forming a protruding concave portion on the single sheet 10 on the back surface side.
The printed layer 11 of the printed single sheet 10 is placed on the mold 15 such that the printed layer 11 faces upward. As shown in FIG. 3 (b), the placement on the mold 15 is performed after the thermoforming recesses 16 are formed immediately below the single sheet 10 so as to correspond to the printing layers 11. A heating plate 17 having a flat joining surface is disposed directly above the mold 15.

As shown in FIG. 3 (c), the printed sheet 11 of the single sheet 10 and the thermoforming recess 16 of the single sheet 15 correspond to the upper surface of the single die 15, respectively.
A positioning pin (not shown) is engaged with the positioning hole 12 for mounting. The heating plate 17 is provided on the upper surface of the single sheet 10.
The single sheet 10 is heated and softened in a state where is pressed.

While supplying compressed air of 1 kg / cm ² or less from the heating plate 17 side to the upper surface of the softened single sheet 10, the air in the thermoforming recess 16 is exhausted from below the mold 15. Then, the lower surface side of the single sheet 10 is sucked. By this suction and heating, a plurality of sheet concave portions 14 corresponding to the respective print layers 11 are formed. As a result, as shown in FIG.
1 is located inside the bottom surface (convex back surface) of the sheet concave portion 14, and the opposite surface is formed as a finger contact portion 9 of the push button 4, that is, a molded sheet 23 serving as an outer skin of the push button 4. .

The finger contact portion 9 is formed in accordance with the shape of the push button 4, and is formed in an arbitrary shape such as a square, a circle, or an ellipse. Further, the thermoforming of the single sheet 10 is not a pressure forming, but may be a vacuum forming in which a thermoplastic sheet is fixed on a mold, and a sheet softened by heating with a heater is sucked into a mold in a vacuum to form the sheet. good. Heating plate 1
The protrusion 7 may be inserted into the recess of the mold 15.

(Injection molding inside the key) FIGS.
(C) is an explanatory view of a step in which resin is filled into each sheet concave portion 14 formed on the molded sheet 23 by injection molding. As shown in FIG. 4A, the finger contact portion 9 of the molded sheet 23 on which the plurality of sheet concave portions 14 are formed is inserted and arranged in the cavity concave portion 22 formed in the cavity 18 of the movable mold plate 20. The molded sheet 23 is placed on the movable mold plate 20 or the fixed mold plate 25 with the molded sheet 23 being inserted into the cavity concave portion 22, and both molds are pressed against each other in this state. When the movable mold plate 20 and the fixed mold plate 25 are crimped, the gate 26 of the fixed mold plate 25 communicates with each of the sheet concave portions 14 of the molded sheet 23.

FIG. 4B shows a joint surface of the movable mold plate 20. As shown in FIG.
The molten resin 27 is supplied into each of the sheet concave portions 14 through the gate 26, and the molten resin 27 is filled flush with the surface of the molded sheet 23 to complete the key sheet 24 provided with the convex key group 7. However, some of the sheet concave portions 14 are left hollow.

The synthetic resin filled in the sheet concave portion 14 is arbitrarily selected according to the characteristics required for the push button such as engineering plastic or synthetic resin elastomer. Preferably, the molded sheet 23 and the molten resin 27 to be injected are preferably selected from synthetic resin materials which are thermally welded to each other.

(Assembly of Keys into Control Panel) Next, an assembling method when assembling the completed key sheet 24 into the control panel will be described. FIG. 5 is a cross-sectional view illustrating a state where the key sheet 24 according to the first embodiment is fixed to a control panel of an electronic device. Each push button 4 of the key sheet 24 is inserted and arranged so as to protrude from the opening 8 of the case cover 3. On the back surface inside the case cover 3, each opening 8
Are formed so as to surround.

The key sheet 24 is provided on the end face 31 of the rib 30.
Are fixedly welded. This heat welding is ultrasonic welding. When ultrasonic vibration energy is applied to the fixing portion 32, the ultrasonic welding is performed on the end face 31 of the rib 30 and the key sheet 24.
Changes into mechanical vibrations at the joint surface, generates frictional heat at the joint surface, melts and welds the portion, and welds the two.

FIG. 6 shows an example in which the end surface 31 of the rib 30 and the key sheet 24 are joined by heat caulking. The protrusion 35 is formed on the end face 31 of the rib 30. Fixed part 3 of key sheet 24
2, a hole 36 is formed in advance. When assembling the key sheet 24 with the case cover 3, the hole 36 of the key sheet 24 is inserted into the projection 35. Next, the tip of the projection 35 is crushed by applying the heated caulking tool 37 to form the caulked portion 38, and the case cover 3 and the key sheet 24 are joined.

The caulking portions 38 are arranged at a plurality of positions around each opening 8. Case cover 3 and key sheet 24
Is an integrated unit, and the end face 3 of the rib 30
Since the joint between the key sheet 1 and the key sheet 24 is thermally welded, no foreign matter, moisture, or the like enters the inside of the electronic device from the outside. An actuator 39 is inserted and arranged in the sheet concave portion 14 of the key sheet 24 where the resin is not filled. The push button 4 drives a switching element 41 and the like mounted on a printed circuit board 40 via an actuator 39.

[Second Embodiment] FIG. 7 shows a second embodiment and is a cross-sectional view showing a state in which another key sheet is fixed to a control panel of an electronic device. In the key sheet 24 according to the first embodiment described above, the main body portion is filled inside the push button 4 by injection molding. Embodiment 2
The push button body 45 fixes the product made in another process to the molded sheet 42 by welding. By the above-described thermoforming, the single sheet 10 is thermoformed into a shape like the cross-sectional structure shown in FIG.

On the other hand, the push button body 45 is formed in advance from a material such as an engineering synthetic resin, and the individual push button bodies 45 are formed. On the lower surface of the push button body 45,
A cylindrical actuator 46 is integrally formed.
A hole 43 is formed in the thermoformed formed sheet 42 corresponding to the arrangement of the push button body 45. The actuator 46 of the push button body 45 is inserted into the hole 43.
The fixing portion 44 of the molded sheet 42 is thermally welded to the end surface 31 of the rib 30. Similarly, the lower surface of the push button body 45 and the upper surface of the molded sheet 42 are heat-welded. These heat welding is preferably performed by ultrasonic ultrasonic welding, but may be performed by heat staking as described above.

[Other Embodiments] In the above-described embodiment, an example in which the push button is arranged on the case cover of the mobile phone has been described. However, a similar function of supporting the push button even if another member is used. Anything that fulfills is acceptable. Therefore, in the present invention, these members are collectively referred to as a control panel. The display unit of the second embodiment prints on the molded sheet 42 by the above-described method, or prints on the upper or lower surface of the push button body 45.

When the display section is arranged on the molded sheet 42, the push button body 45 is preferably made of a transparent material. In the case of ultrasonic welding between the molded sheet 42 having a printing layer and the push button body 45, it is preferable to mix a primer agent into the printing layer in order to improve the welding performance.

Further, in the above embodiment, the case cover 3
The end face 31 of the rib 30 and the fixing portion 32 of the key sheet 24 are ultrasonically welded. However, instead of heat fusion, a primer such as a silicon-based primer is
May be applied and then heat-sealed with this interposed. Further, when the injection molding is performed in a state where the temperature of the molten resin in the injection molding is low, the two may be joined by an adhesive action instead of the heat fusion.

In this case, an adhesive is applied to the ribs 30 of the case cover 3 in advance and adheres to the fixing portion 32 of the key sheet 24. At this time, the key sheet 24 and the case cover 3
Means that the two are bonded mainly by an adhesive action, not by thermal fusion. Therefore, the case cover 3 may be not only an engineering plastic but also a magnesium alloy formed by injection molding, a metal plate formed by plastic working, an alloy for die casting formed by die casting, or the like.

What has been described above is a heated caulking tool 37.
, And crush the tip of the projection 35 to form the caulked portion 3.
8 and the case cover 3 and the key sheet 24 were joined. When the case cover 3 is made of metal, the caulking tool 37 is not heated but may be a normal caulking tool 37. The protrusion 35 is plastically deformed by the caulking tool 37, and the key sheet 24 is fixed to the case cover 3.

[0033]

As described above, according to the present invention, it is possible to manufacture a control panel with good security and a manufacturing thereof in a small number of steps. Further, since the display portion of the push button is covered with the outer skin or disposed on the back surface, it is possible to prevent dirt, peeling, and the like due to finger contact or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view of a portable telephone employing the present invention.

FIG. 2 is a plan view of a printed single sheet serving as an outer skin of a push button.

FIGS. 3 (a) to 3 (d) are explanatory views of a step of thermoforming a single sheet into a molded sheet.

FIGS. 4A to 4C are cross-sectional views illustrating a manufacturing process of a key sheet from a molded sheet.

FIGS. 5A to 5D are cross-sectional views illustrating a structure of a control panel of the electronic device according to the first embodiment.

FIGS. 6A and 6B are cross-sectional views showing a structure in which a key sheet and a case cover are fixed by heat caulking.

FIG. 7 is a cross-sectional view illustrating a structure of a control panel of the electronic device according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Portable telephone 2 ... Telephone main body 3 ... Case cover 4 ... Push button 8 ... Opening 9 ... Finger contact part 10 ... Single sheet 11 ... Printing layer 14 ... Sheet concave part 15 ... Mold 17 ... Heating plate 19 … Push button skin 23… Molded sheet 24… Key sheet

Claims (11)

[Claims] 1. A push button (4) inserted into an opening (8) of a control panel (3) such as an electronic device, and the push button is fixed to the control panel (3), and the push button is attached to the control panel (3). And a molded sheet (23) of a thermoplastic synthetic resin molded so as to be elastically bent and supported as an outer skin of the push button. 2. A control panel provided with a sheet forming push button unit according to claim 1, wherein said control panel (3) is made of a thermoplastic synthetic resin, and said molded sheet (23) and said control panel (3). )
A control panel provided with a sheet forming push button unit, which is integrally fixed by thermal bonding performed by plastically deforming by heating. 3. A control panel provided with a sheet forming push button unit according to claim 1, wherein said control panel (3) is made of metal, and said forming sheet (23) and said control panel (3) are formed of metal. Is
A control panel comprising a sheet forming push button unit, wherein the control panel (3) is integrally fixed by caulking by plastically deforming the control panel (3). 4. The sheet according to claim 2, wherein the heat-bonded portion is ultrasonically welded by ultrasonic vibration energy. Control panel with molded pushbutton unit. 5. A push button body (45) inserted into an opening (8) of a control panel (3) such as an electronic device, and the push button body (45) fixed to the control panel (3). A sheet forming push button unit comprising a molded sheet (42) of a thermoplastic synthetic resin which is elastically flexibly supported by the control panel (3) and is formed by fixing the push button body (45). Control panel. 6. A control panel provided with a sheet forming push button unit according to claim 5, wherein said control panel (3) is made of a thermoplastic synthetic resin, and said formed sheet and said control panel (3) are A control panel provided with a sheet forming push button unit, which is integrally fixed by thermal bonding performed by plastically deforming by heating. 7. A control panel provided with a sheet forming push button unit according to claim 6, wherein said heat-bonded portion is ultrasonically welded by ultrasonic vibration energy. Control panel with push button unit. 8. A molded sheet (23) is formed by thermoforming a single sheet (10) of a thermoplastic synthetic resin to form a plurality of recesses to be outer skins of the push buttons, and the molded sheet (23) is formed by injection molding. Mold (20, 25)
A sheet forming push button, wherein said key sheet (24) is integrally fixed to a control panel (3) by thermal bonding. A method for manufacturing a control panel including a unit. 9. A molded sheet (42) is formed by thermoforming a single sheet (10) of a thermoplastic synthetic resin, and the molded sheet (42), a push button body (45) and a control panel (10) of the thermoplastic synthetic resin. 3) The method of manufacturing a control panel provided with a sheet forming push button unit, wherein the control panel is fixed by thermal bonding. 10. A method of manufacturing a control panel having a sheet forming push button unit according to claim 8 or 9, wherein said thermal bonding is performed by ultrasonic welding using ultrasonic vibration energy. A method for manufacturing a control panel including a sheet forming push button unit. 11. A method of manufacturing a control panel comprising a sheet forming push button unit according to claim 8 or 9, wherein said control panel (3) is made of metal, and said control sheet (23, 42) and The control panel (3)
The method for manufacturing a control panel having a sheet forming push button unit, wherein the control panel (3) is integrally fixed by caulking by plastically deforming the control panel (3).