Case structure for portable electronic device, portable electronic device and method for manufacturing same

The present invention includes: a rear case (12) that includes a quadrangular first opening (26) into which a part of a first electronic component (21) to be housed inside the rear case (12) is inserted, and a rear panel arranged at a position where the rear panel covers the first opening (26) of the rear case (12). The rear case (12) includes a recess portion (30) extending from an inner peripheral side of the first opening (26) toward an outer peripheral side of the first opening (26) at each corner of the first opening (26).

TECHNICAL FIELD

The present invention relates to a case structure for a portable electronic device including a case member housing an electronic component inside, a portable electronic device, and a method for manufacturing a portable electronic device.

BACKGROUND ART

As an example of portable electronic devices, a folding portable telephone includes a receiver section-side housing in which a main display panel is arranged, and a transmitter section-side housing in which operation buttons are arranged, the receiver section-side housing and the transmitter section-side housing being pivotally connected via a hinge portion. The receiver section-side housing includes a combination of a pair of a front case and a rear case.

As an example of a receiver section-side housing included in a portable telephone related to the present invention, there is a known configuration in which a rear cover, which is made of a transparent resin material, is attached to a rear case, which is made of an opaque resin material for decorative effect enhancement (see, for example, patent literature 1).

Furthermore, where a portable electronic device employs a configuration in which light-emitting components such as LEDs (light-emitting diodes) and/or a sub display panel are arranged on the rear case side, a rear cover covers, these light-emitting components, is made of a light-transmissive material while a rear case is made of an opaque material.

In addition, in order to provide two different types of decorative processing, for example, the housing of a portable telephone has a configuration in which a rear cover, to which decorative, processing applied, which is different from decorative processing applied to a rear case, is attached to the rear case.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

As described above, in recent years, portable telephones that include a structure in which a rear cover is attached to a rear case, are becoming increasingly thinner. In connection with that, in order to reduce the thickness of the housing to the extent equal to or exceeding an extent in which electronic components on a circuit board housed inside the housing and the rear cover interfere with each other, there has been proposed a configuration in which a rear case includes openings, into which parts of such components in a height (thickness) direction, i.e., a direction perpendicular to a mounting surface of a circuit board, are inserted, that is, “structure for preventing contact with a component”. As described above, where an electronic component having a quadrangular shape on a plane parallel to a mounting surface of a circuit board is inserted into the opening of a rear case, the opening having a quadrangular shape whose size is somewhat larger than the external dimensions of the electronic component. As described above, the opening is formed as small as possible, thereby suppressing a decrease in mechanical strength in the rear case due to the formation of the opening.

However, where the rear case includes the quadrangular opening, when an external force such as an impact or a pressing force from the outside of the housing is applied to the housing while the portable telephone is being handled, stress concentrates on the four corners of the opening. Consequently, cracking may occur in the our corners of the opening of the rear case, resulting in breakage of the rear case.

In order to prevent such stress concentration, each of the four corners of the quadrangular opening can have a circular arc shape. However, where a quadrangular electronic component is inserted into the opening with its corner portions each having a circular arc shape, it is necessary to prevent interference between the angulated corner portions of the electronic component and the corner portions of the opening. Therefore, it is necessary to form the opening large according to the amount of interference between the angulated corner portions of the electronic component and the corners portions of the opening, which results in a decrease in the mechanical strength of the rear case in which the opening is formed.

An object of the present invention to provide a case structure for a portable electronic device, a portable electronic device and a method for manufacturing the same, which can solve the aforementioned problem. An example of the object is to prevent breakage of a case member of a portable electronic device even though the portable electronic device is designed to be thinner.

Solution to Problem

A case structure for a portable electronic device according to one aspect of the present invention includes: a case member that has a quadrangular opening into which a part of an electronic component, which is to be housed inside the case member, is inserted; and a cover member which is arranged at a position where the cover member covers the opening of the case member. Each corner portion of the opening of the case member includes a recess portion extending from an inner peripheral surface of the opening toward an outer peripheral side of the opening.

Also, a portable electronic device according to the present invention includes: a case structure for a portable electronic device according to the present invention; and a circuit board with an electronic component mounted thereon.

Also, a method for manufacturing a portable electronic device according to the present invention includes: forming a case member that has an opening, into which a part of an electronic component to be housed inside the case member is inserted; and forming a cover member arranged at a position where the cover member covers the opening of the case member. Forming a case member includes forming a recess portion extending from an inner peripheral surface of the opening toward an outer peripheral side of the opening at each corner of the opening.

Advantageous Effect of Invention

As described above, the present invention enables preventing breakage of a case member of a portable electronic device even though the portable electronic device is designed to be thinner.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a specific exemplary embodiment of the present invention will be described with reference to the drawings.

A portable telephone according to an exemplary embodiment will be described as an example of a portable electronic device according to the present invention. As illustrated inFIGS. 1 and 2, portable telephone1includes receiver section-side housing6in which a main display panel is arranged, and transmitter section-side housing7in which operation buttons9are arranged, receiver section-side housing6and transmitter section-side housing7being pivotally connected via hinge portion8.

Receiver section-side housing6includes a pair of front cases11and rear case12, and rear cover13, which is a cover member, rear cover13being assembled to rear case12, which is a cover member. Front case11and rear case12each is made of an opaque resin material. Rear cover13includes rear cover body13aand rear panel13battached to rear cover body13a. In rear cover13, rear cover body13aincludes an opaque resin material, and rear panel13bincludes a light-transmissive resin material.

Also, as illustrated inFIG. 4, in receiver section-side housing6, circuit board15with electronic components16mounted thereon are arranged, and electronic components16are housed inside rear case12. Furthermore, in receiver section side-housing6, main display panel17, for example, a liquid-crystal display panel or an organic EL (electroluminescence) display, is arranged. Main display panel17is covered by front panel18.

As illustrated inFIGS. 2 and 3, rear case12includes quadrangular first opening26into which a part in a thickness direction of first electronic component21to be housed inside rear case12is inserted. Also, rear case12includes rectangular second opening27into which a part in a thickness direction of second electronic component22on circuit board15is inserted. As illustrated inFIG. 5, first and second electronic components21and22, which are different from each other in size in a direction parallel to a mounting surface of circuit hoard15, are inserted into first opening26and second opening27, respectively, and the opening areas of first opening26and second opening27are different from each other.

Corner portions of first opening26and second opening27include respective recess portions30extending from respective inner peripheral surfaces of first and second openings26and27toward respective outer peripheral sides of first and second openings26and27. Rear case12including first and second openings26and27that contain recess portions30is integrally formed by a resin material. As illustrated inFIG. 6, for example, each recess portion30has a circular arc shape with point O, at which straight lines extending from two adjacent inner peripheral surfaces of respective first or second opening26or27cross each other, as a center thereof. Also, opposite ends of the circular arc included in each recess portion30are smoothly continuous with the inner peripheral surfaces of respective second opening26or27so that each forms an arc shape.

As a result of recess portions30being formed in such a manner as described above, no parts of openings26and27on which stress concentrates can be generated while collision of angulated corners arranged inside quadrangular electronic component openings26and27with corners of openings26and27is prevented. Accordingly, even when receiver section-side housing6is subjected to an external impact, while portable telephone1is being handled, breakage can be prevented form occurring in openings26and27of rear case12.

The shape of each recess portion30is not limited to the aforementioned circular arc shape, and any shape formed so as to prevent stress concentration and avoid collision of angular corners of an electronic component with recess portion30can be employed. It should be understood that the shape of each recess portion30may be another shape such as, for example, a shape including an extension portion extending from a corner of an opening along a diagonal of the opening and a circular arc portion provided at an end of the extension portion.

Furthermore, as illustrated inFIG. 5, first opening26and second opening27are provided in such a manner that adjacent inner peripheral surfaces thereof are partially connected to each other. As a result of first opening26and second opening27being connected to each other, the number of recess portions30provided at respective corners can be reduced. Thus, the moldability of rear case12can be enhanced while structures for cavities that are contained in a mold for rear case12are simplified.

As illustrated inFIG. 7, which is an enlarged view of a part ofFIG. 4, parts of first and second electronic components21and22in a thickness direction, i.e., a direction perpendicular to the mounting surface of circuit board15, are inserted inside first and second openings26and27of rear case12. First and second electronic components21and22do not project to rear panel13bside from first and second openings26and27.

In rear case12, an edge portion of each of first and second openings26and27has a thickness of around 0.8 mm, and rear panel13bhas a thickness of around 1 mm.

Furthermore, as illustrated inFIGS. 3 and 4, rear case12includes rectangular third opening28into which a part on a side surface side of third electronic component23(right-side angulated corner inFIG. 4) is inserted. As with first and second openings26and27, third opening28includes recess portions30at respective corner portions thereof.

Furthermore, rear case12includes slit-like fourth opening29into which a part on a side surface side of fourth electronic component24(left-side angulated corner inFIG. 4) is inserted. As with first and second openings26and27, fourth opening29includes recess portions30at respective corner portions thereof.

First to fourth openings26to29of rear case12are then covered by rear panel13bof rear cover13. Rear panel13bis bonded to rear cover body13avia an adhesive. Rear case12is bonded to rear panel13bvia an adhesive.

Furthermore, as illustrated inFIGS. 2 and 3, sub display panel31and LED32are arranged in rear case12. Display on sub display panel31and a light-emission state of LED32can be viewed through rear panel13b.

Next, a method for manufacturing a portable telephone configured as described above will be described.

A manufacturing method according, to the present exemplary embodiment includes the steps of funning rear case12including first to fourth openings26to29into which parts of first to fourth electronic component21to24to be housed inside rear case12are inserted; and forming rear cover13that includes rear panel13battached to rear case12, rear cover13covering first to fourth openings26to29of rear case12.

The step of forming rear case12includes forming recess portions30extending from respective inner peripheral surfaces of openings26to29toward respective outer peripheral sides of openings26to29at respective corner portions of first to fourth openings26to29. The step of forming rear case12includes integrally molding rear case12that has respective openings26to29in which recess portion30is formed, by means of a mold, using a resin material.

As described above, portable telephone1includes rear case12that has quadrangular first opening26into which a part in a thickness direction of first electronic component21is inserted, and at respective corners of first, opening26of rear case12, recess portions30extending respective inner peripheral surfaces of first opening26toward respective outer peripheral sides of first opening26are provided. This configuration enables preventing a decrease in the mechanical strength of rear case12, which occurs when first opening26of rear case12is formed so as to have the smallest possible opening area according to the size of first electronic component21, as well as preventing a collision between the angulated corners of first electronic component21and the corners of first opening26. Consequently, portable telephone1enables a decrease in thickness of the entire device as well as preventing breakage of rear case12.

Although the above exemplary embodiment has been described in terms of a configuration in which openings that include recess portions are provided in a rear case, the configuration according to the present invention is not limited to such configuration in which a rear case includes openings, and openings may be provided in another member that houses electronic components inside. For example, when a portable telephone employs a structure in which a support plate supporting a circuit board is arranged on the from case side, openings that include recess portions may be provided in the support plate.

Furthermore, although a portable electronic device according to the present invention has been described taking a portable telephone according to an exemplary embodiment as an example, the portable electronic device according to the present invention is not limited to a portable telephone, and the present invention is suitable for use in, for example, PDAs (personal data assistant) or portable communication devices.

Although the present invention has been described above with reference to an exemplary embodiment, the present invention is not limited to the exemplary embodiment. Various alternations that can be easily understood by a person skilled in the art can be made to the configuration and the details of the present invention within the scope of the present invention.

The present application has been filed claiming as priority right based on Japanese Patent Application 2009-109336 filed Apr. 28, 2009, the entire disclosure which is incorporated herein by reference.