Embodiments described herein relate generally to a sub-assembling method, a sub-assembled unit, and an apparatus with the sub-assembled unit.
Some products such as electronic apparatuses are formed by combining metallic components and synthetic resin components. When a metallic component and a synthetic resin component are joined and fixed to each other, various methods such as securing by screws, fitting, adhering, deforming and fixing the metallic component, welding the synthetic resin component, and injection molding the synthetic resin inserting the metallic component, etc., can be adopted. When the synthetic resin is a thermoplastic resin and is not removed during maintenance, the synthetic resin component can be fixed to the metallic component by welding. Welded components of components adopted into a precision instrument are required to have assembling and manufacturing tolerances with a high degree of accuracy.
A general architecture that implements the various features of the embodiments will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate the embodiments and not to limit the scope of the invention.
Various embodiments will be described hereinafter with reference to the accompanying drawings.
In general, according to one embodiment, a sub-assembling method for producing a sub-assembled unit comprising an attaching surface by combining a rigid member and a thermoplastic resin, the sub-assembling method includes fitting, welding and adhering. In the fitting, a pin of the thermoplastic resin is fit into a hole of the rigid member penetrating on a side of the attaching surface. In the welding, a tip of the pin protruding from the hole is welded to a recessed portion formed around the hole on the side of the attaching surface. In the adhering, a sheet punched at a portion corresponding to the recessed portion of the rigid member is adhered to the rigid member to provide the attaching surface. The sub-assembling method can maintain the flatness of the attaching surface of the sub-assembled unit after the pin of the thermoplastic resin is welded on the hole of the rigid member.
A sub-assembling method of a first embodiment will be described with reference to
The rigid member 11 comprises a hole 111 penetrating from the side of the attaching surface 102 to the opposite side thereof, and a recessed portion 112 formed around the hole 111 on the side of the attaching surface 102. The rigid member 11 may be formed of a metal or a synthetic resin, if it can bear the strength of the assembled sub-assembled unit 10. If the rigid member 11 is formed of a metal, the rigid member 11 can be cheaply manufactured by performing die-cut and bending at the same time by means of press forming such as punching. The rigid member 11 is formed by overlapping two members in
As shown in
The head H of the welding apparatus is pushed against the rigid member 11 such that the melted pin 121 is contained in the recessed portion 112 of the rigid member 11. It is preferable that the welding apparatus does not form a burr B at the melted pin 121 when the head H is separated from the rigid member 11. Actually, however, the melted pin 121 sticks to the head H and a small burr B is formed as shown in
In the present embodiment, the sheet 13 is adhered to the rigid member 11 after welding as shown in
The sub-assembled unit 10 of a second embodiment will be described as a keyboard unit with reference to
When the side on which the key tops 11 are mounted is an upper surface 10a of the sub-assembled unit 10, a lower surface 10b of the sub-assembled unit 10 is the attaching surface 102. Pins 121 are arranged on an outer periphery and portions located between the key tops 14 of the frame, on the lower surface of the thermoplastic resin 12 facing the rigid member 11. Holes 111 penetrate in a thickness direction at positions on the rigid member 11 corresponding to the pins 121, and recessed portions 112 are formed around the holes 111 on the side of the lower surface of the rigid member 11. The rigid member 11 comprises a substrate 113 arranged to face the side of the thermoplastic resin 12 and having contact points at positions corresponding to the respective key tops 14, supporting members which support the respective key tops 14 to allow the key tops 14 to be pressed, and springs (cup-shaped elastomers in this case) for returning the pressed key tops 14 to the initial positions.
In the sub-assembled unit 10 of the second embodiment, the sheet 13 is formed of a transparent synthetic resin member which propagates light, and serves as a lightguide plate. Therefore, the sub-assembled unit 10 further comprises a light source unit on the side of the lower surface of the sheet 13. The light source unit includes light-emitting diodes (LEDs) interspersed within a range overlapping the sheet 13. The optical unit is adhered to the lower surface of the sheet 13 together with a film for efficiently reflecting light output from the LEDs on the sheet 13 serving as a lightguide plate. Holes may be punched in the sheet 13 in accordance with positions of the LEDs.
Windows are formed on the rigid member 11 and the substrate 113 to output the light propagated by the sheet 13 to the side of the key tops 14. Each of the key tops 14 has a light transmissive portion which allows the light propagated by the sheet 13 to pass through, for example, a letter portion corresponding to each of the key tops 14. The letters of the key tops 14 thereby emit light. It should be noted that holes 131 punched at positions on the sheet 13 corresponding to the recessed portions 112 do not interfere with guidance of the light from the light source unit to the light transmissive portions of the key tops 14 since each of the connected portions 101 between the holes 111 and the pins 121 is located at a position where the key top 14 is not positioned.
In the above-described sub-assembled unit 10, the pins 121 of the thermoplastic resin 12 are inserted into the respective holes 111 of the rigid member 11 to which the substrate 113 is adhered and the supporting members, etc., of the key tops 14 are mounted, and welding is performed at once. The shape of each of the pins 121 before and after welding has been described in the first embodiment. After the pins 121 are welded, the sheet 13 serving as a lightguide plate is adhered to the lower surface of the rigid member 11, and a reflection film and a light-shielding film are further adhered thereto together with the light source unit.
The sheet 13 of the present embodiment has a function of a lightguide plate in addition to a function of maintaining the flatness of the attaching surface 102 of the sub-assembled unit 10. Therefore, the mounting efficiency of an apparatus which adopts the above-described sub-assembled unit 10 is increased.
Next, an apparatus 1 of a third embodiment will be described as a portable computer with reference to
The apparatus 1 shown in
Similarly to the first or second embodiment, the sub-assembled unit 10 of the third embodiment comprises the sheet 13. Therefore, even if the burr B is formed at the tip of the pin 121 by welding as shown in
In the apparatus 1 of the third embodiment configured as described above, since the attaching surface 102 is flat, the sub-assembled unit 10 is not come off because of age deterioration when the sub-assembled unit 10 is adhered to the mounted portion 21 of the first housing 2 only by adhesive or double-sided adhesive tape. In addition, the construction management of the burr B formed at the tip of the welded pin 121 is facilitated.
In the second embodiment, an example in which the sheet 13 is a lightguide plate has been described in detail. However, if the letters of the key tops 14 are not made to emit the light, the sheet 13 does not need to be a lightguide plate. By forming the sheet 13 of a conductive member such as foil of aluminum alloy or stainless alloy, a radio wave radiated from electronic components inside the first housing 2 can be prevented from leaking to the side of the mounted portion 21. In addition, heat generated by the electronic components inside the first housing 2 can be easily dissipated. Furthermore, a member which has anisotropy in thermal conductivity, i.e., of which thermal conductivity in the in-plane direction of the sheet 13 is larger than thermal conductivity in the out-of-plane direction, such as a layered member may be adopted as the sheet 13. Since the heat radiation area of the sheet 13 is expanded by the rapid spread of the heat transmitted from the electronic components along the surface of the sheet 13, the heat radiation efficiency of the apparatus 1 is increased.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
This application claims the benefit of U.S. Provisional Application No. 62/003,923, filed May 28, 2014, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
62003923 | May 2014 | US |