JP2013150067A - Portable terminal cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable terminal cover which surely insulates heat from a heating source of a portable terminal to avoid a discomfort in the case where a user holds the portable terminal in the hand, and in which heat radiating/cooling performances of the portable terminal can also be maintained.SOLUTION: A portable terminal cover 100 comprises an external cover 104 which covers a casing of a portable terminal 102 and of which the outer surface is held by a user, projections 116, 118, 120, 122 which extend from an inner surface of the external cover 104 to a casing side and form an air layer 114 between the inner surface of the external cover 104 and the casing side, and vent holes 124, 126 which are provided in the external cover 104 and circulates outside air with the air layer 114.

Description

  The present invention relates to a portable terminal cover.

  A portable terminal usually includes a heat source such as a CPU or a battery. If the gripping surface of the portable terminal is heated due to the heat generated by the heat source, the user who grips it may feel uncomfortable. For this reason, conventionally, in the design of portable terminals, measures are taken when the heat of the gripping surface is likely to be a problem. However, there are limits to the measures from the mechanical point of view of mobile terminals, and there are many cases in which current solutions must be solved by changing software or the like.

  On the other hand, Patent Document 1 discloses an option cover for a portable terminal. In Patent Document 1, an optional function circuit unit serving as a heat source is separated from the mobile terminal body, and the optional function circuit unit is integrated with the option cover via a heat insulating material having low thermal conductivity. Thereby, heat generation of the mobile terminal body can be prevented, and the heat generation effect of the option function circuit unit can be reduced even when the mobile terminal equipped with the option cover is gripped by hand.

JP 2005-252687 A

  As described above, since the user may feel uncomfortable when the gripping surface of the mobile terminal is heated, this needs to be avoided. However, in the technique of Patent Document 1, an optional function circuit unit serving as a heat source is separated from the mobile terminal body, and is disposed on an option cover that is a part gripped by the user via a heat insulating material. Since thermal insulation cannot completely prevent heat conduction, it must be said that this increases the possibility of causing discomfort to the user. That is, the technique disclosed in Patent Document 1 is reversed as a countermeasure that can be taken when the heat of the gripping surface is likely to be a problem in the design of the mobile terminal. Therefore, at present, it is not possible to avoid discomfort when a user holds the cover on the portable terminal and grips it by hand.

  The present invention has been made in view of such a problem, and reliably dissipates heat from the heat source of the mobile terminal to avoid discomfort when the user grips it by hand, and heat dissipation of the mobile terminal. -It aims at providing the portable terminal cover which can also maintain cooling performance.

  In order to solve the above problems, a typical configuration of a portable terminal cover according to the present invention includes an outer cover that is put on the casing of the portable terminal and whose outer surface is gripped by the user, and extends from the inner surface of the outer cover to the casing side. And a protrusion that forms an air layer between the inner surface and the housing side, and a vent that is provided on the outer cover and communicates the air layer with the outside air.

  The outer cover is preferably formed of a resin having flexibility, and further includes a hard support frame that holds the shape of the outer cover on the housing side of the outer cover.

  The hard support frame is a metal heat radiating plate with high thermal conductivity, and a heat conduction sheet formed on the housing side of the support frame and made of a material softer than the support frame and having a shape that is almost the same as the support frame. It is good to have more.

  The support frame may be a leaf spring that exerts an elastic force in a direction in close contact with the housing when the mobile terminal cover is attached.

  The outer cover has a back surface portion that covers the back surface of the housing and a side surface portion that covers the side surface of the housing, and the side surface portion has a rib with an arc-shaped cross section on the inner surface, and the rib is in line contact with the side surface of the housing. Good.

  According to the present invention, it is possible to reliably insulate the heat from the heat source of the mobile terminal to avoid discomfort when the user grips it by hand, and to maintain the heat dissipation / cooling performance of the mobile terminal. It is possible to provide a portable terminal cover.

It is a figure which shows the portable terminal equipped with the portable terminal cover concerning embodiment of this invention. It is a disassembled perspective view of the portable terminal cover of FIG. It is AA sectional drawing of Fig.1 (a). It is BB sectional drawing of Fig.1 (a).

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  FIG. 1 is a diagram showing a mobile terminal 102 equipped with a mobile terminal cover 100 according to an embodiment of the present invention. FIG. 1A is a perspective view of the portable terminal 102 viewed from the front side, and FIG. 1B is a perspective view of the portable terminal 102 viewed from the back side. As shown in FIGS. 1A and 1B, the mobile terminal cover 100 is an optional cover that covers the back and side surfaces of the casing of the mobile terminal 102.

  FIG. 2 is an exploded perspective view of the portable terminal cover 100 of FIG. As shown in FIG. 2, the mobile terminal cover 100 includes an external cover 104, a support frame 106, and a heat conductive sheet 108.

  The outer cover 104 is put on the casing of the mobile terminal 102 and the outer surface is gripped by the user. The external cover 104 includes a back surface portion 110 that covers the back surface of the housing of the mobile terminal 102 and a side surface portion 112 that covers the side surface of the housing. The side surface portion 112 includes an upper side surface 112a, a lower side surface 112b, a left side surface 112c, and a right side surface 112d. The back surface portion 110 is provided with four protrusions 116, 118, 120, and 122 that extend from the inner surface of the back surface portion 110 toward the housing.

  In the present embodiment, the outer cover 104 is formed of a resin material having flexibility and cushioning properties such as silicon. By using such a resin material, it is possible to improve the impact resistance at the time of dropping and the ease of covering the outer cover 104 to the housing. In addition, it is possible to ensure the texture when the user grips with hands.

  FIG. 3 is a cross-sectional view taken along the line AA in FIG. As shown in FIG. 3, in the mobile terminal cover 100, the protrusions 116, 118, 120, and 122 are air without interposing a heat source between the protrusions 116, 118, 120, and 122 and the housing of the mobile terminal 102 that includes a heat source such as a CPU or battery. Layer 114 is formed.

  There are three patterns of heat transfer: heat conduction, convective heat transfer, and heat radiation (radiation). The heat conduction is due to the movement of the individual molecules constituting the material being propagated to neighboring molecules. For example, the heat conduction of a round bar is defined by the following formula 1. The heat transfer amount Q by heat conduction depends on the cross-sectional area A and the thermal conductivity λ. Convective heat transfer is a phenomenon in which heat is transferred from a high temperature side to a low temperature side when a temperature difference exists between a solid wall and a fluid along the solid wall. The heat transfer amount QCONV by convective heat transfer is defined by the following formula 2, and depends on the heat transfer area S and the heat transfer coefficient h. Thermal radiation (radiation) is a phenomenon in which a part of thermal energy generated by the movement of molecules in a high-temperature object becomes radiation energy and propagates through space in the form of electromagnetic waves. The energy qrad. Radiated per unit time from the unit area of the object surface is defined by the following formula 3.

  Since the protrusions 116, 118, 120, and 122 form the air layer 114, heat conduction from the back surface of the casing of the portable terminal 102 that is generally equipped with a battery or the like can be prevented. In this case, heat transfer by convective heat transfer cannot be prevented, but convective heat transfer is not as easy to transfer heat to the outer cover 104 as heat conduction (the heat transfer coefficient h of dry air is extremely low). Therefore, by forming the air layer 114, heat from the heat source of the mobile terminal 102 can be reliably insulated, and uncomfortable feelings when the user grips with hands can be avoided.

  The four protrusions 116, 118, 120, and 122 each have a hemispherical shape, and form an air layer 114 in point contact with the support frame 106 positioned on the housing side. Due to the presence of the four protrusions 116, 118, 120, 122, the outer cover 104 is not completely crushed even when grasped by hand, and the air layer 114 is not lost. Moreover, since it is a point contact, the heat conduction to the external cover 104 through the contact surface can be suppressed to a negligible level. In addition, the protrusion part of this embodiment is an illustration and is not necessarily limited to this, For example, you may form the air layer 114 so that a framework may be attached to the inner side of the outer cover 104 with a metal or resin.

  As shown in FIG. 2, vent holes 124 and 126 are provided that allow the air layer 114 and the outside air to communicate from the upper side surface 112 a to the back surface portion 110 and from the lower side surface 112 b to the back surface portion 110. Thereby, the air circulation inside a cover can be ensured and it can avoid that the thermal radiation and cooling performance of the portable terminal 102 main body are inhibited. Here, since the vent hole is not provided from the left side surface 112c or the right side surface 112d, which is generally a part that can be gripped by hand, to the back surface part 110, there is no possibility that the heated air is applied to the user's hand. In addition, there is no possibility of blocking the vent hole with the user's hand. In the present embodiment, the outer cover 104 is cut out in the longitudinal direction to form the vents 124 and 126, but the vents 124 and 126 may be cut out in the short direction.

  In this embodiment, a part of the outer cover 104 having flexibility and cushioning is crushed when it is gripped by a hand to push out the air inside, and when the hand is released, the shape is restored and the air is restored. Since it sucks in, it has an effect like a pump that promotes air circulation. By promoting air circulation, the heat dissipation / cooling performance of the portable terminal 102 can be enhanced.

  As shown in FIGS. 2 and 3, the support frame 106 is provided on the housing side of the outer cover 104 and is a substantially “X” -shaped hard member that holds the shape of the outer cover 104. This is because the outer cover 104 formed of a resin material such as silicon has low rigidity and it is difficult to maintain its shape, so that a hard support frame 106 serving as a skeleton (in other words, a beam) is inserted to improve usability. Therefore, if the outer cover 104 is not silicon or the like and has a certain degree of rigidity, the support frame 106 is not essential. In the present embodiment, the four corners of the support frame 106 are shaped along the four corners of the outer cover 104. The four corners of the outer cover 104, the support frame 106, and a heat conductive sheet 108 described below are fitted around the front surface of the casing of the mobile terminal 102.

  In the present embodiment, the support frame 106 is made of a metal having high thermal conductivity, and also functions as a heat radiating plate that radiates heat transmitted from a heat generation source included in the mobile terminal 102. In order to increase the surface area, the support frame 106 may be provided with unevenness by, for example, sand blasting, coated with a paint that improves the emissivity, or a material with high heat dissipation performance. The support frame 106 can improve the heat dissipation performance.

  Further, in the present embodiment, the support frame 106 is a leaf spring that exerts an elastic force in a direction in close contact with the housing, that is, the heat conductive sheet 108 when the mobile terminal cover 100 is attached. Specifically, here, the support frame 106 is formed to be bent so as to protrude toward the housing when the portable terminal cover 100 is attached (the bent portions are illustrated as “spring shape portions 128 and 130”). ) Elastic force is applied to the center.

  By improving the adhesiveness (contact area) with the heat conductive sheet 108 by using the support frame 106 as a leaf spring, heat conduction to the support frame 106 can be enhanced and heat dissipation performance can be improved. Further, by causing the support frame 106 to function as a leaf spring, there is an effect of absorbing an impact at the time of dropping or the like and reducing the influence on the portable terminal 102.

  As for the case where the outside of the casing of the mobile terminal 102 serves as an antenna, if the support frame 106 is made of metal, there may be a problem in the reception sensitivity. In such a case, the support frame 106 may be formed of another hard member having a certain degree of rigidity, such as non-conductive resins.

  The heat conductive sheet 108 has a shape that is substantially the same as that of the support frame 106 and is a member provided on the housing side of the support frame 106. The heat conductive sheet 108 is formed of a softer material than the support frame 106. If the support frame 106 having high rigidity is directly brought into contact with the casing of the portable terminal 102, damage may occur. Therefore, the heat conductive sheet 108 formed of a soft material is interposed between the support frames 106 to suppress the damage. Further, the heat conductive sheet 108 also has an effect of increasing heat conduction to the support frame 106.

  4 is a cross-sectional view taken along the line BB in FIG. As shown in FIG. 4, the side surface portions 112 (the left side surface 112 c and the right side surface 112 d) of the outer cover 104 have ribs 132 and 134 having arc-shaped cross sections extending on the inner surface thereof in the extending direction of the side surface of the casing of the mobile terminal 102. The ribs 132 and 134 are in line contact with the side surface of the housing. As a result, the contact area between the outer cover 104 and the side surface of the housing can be reduced, so that the influence of heat conduction can be suppressed as much as possible, and the heat that can be transferred to the user's handle can be reduced as much as possible. In addition, although it is a line contact here, if it applies to this (for example, point contact), there exists an equivalent effect.

  According to the mobile terminal cover 100 described above, it is possible to reliably insulate the heat from the heat source of the mobile terminal 102 and avoid discomfort when the user grips it by hand. In addition, heat is transmitted from the heat source of the portable terminal 102 to the heat conductive sheet 108 and the support frame 106 by heat conduction, and heat dissipation is promoted by convective heat transfer by air flowing in from the vent 124 and the vent 126. It is also possible to improve the heat dissipation / cooling performance.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  The present invention can be used as a portable terminal cover.

DESCRIPTION OF SYMBOLS 100 ... Mobile terminal cover, 102 ... Mobile terminal, 104 ... External cover, 106 ... Support frame, 108 ... Heat conduction sheet, 110 ... Back surface part, 112 ... Side surface part, 112a ... Upper side surface, 112b ... Lower side surface, 112c ... Left side Surface, 112d ... Right side surface, 114 ... Air layer, 116, 118, 120, 122 ... Projection, 124, 126 ... Vent, 128, 130 ... Spring-shaped part, 132, 134 ... Rib

Claims (5)

An outer cover that is put on the casing of the mobile terminal and whose outer surface is gripped by the user;
A protrusion that extends from the inner surface of the outer cover toward the housing and forms an air layer between the inner surface and the housing;
A vent hole provided in the outer cover for communicating the air layer and outside air;
A portable terminal cover characterized by comprising: The outer cover is formed of a flexible resin,
The mobile terminal cover according to claim 1, further comprising a hard support frame that holds a shape of the outer cover on the housing side of the outer cover. The hard support frame is a heat sink made of metal with high thermal conductivity,
The portable terminal according to claim 2, further comprising a heat conductive sheet formed on a side of the support frame that is substantially in the same shape as the support frame and formed of a softer material than the support frame. cover.   The mobile terminal cover according to claim 2 or 3, wherein the support frame is a leaf spring that exerts an elastic force in a direction in close contact with the housing when the mobile terminal cover is attached. The external cover has a back surface portion covering the back surface of the housing and a side surface portion covering the side surface of the housing,
The portable terminal cover according to any one of claims 2 to 4, wherein the side surface portion has a rib having an arc-shaped cross section on an inner surface thereof, and the rib is in line contact with the side surface of the housing.

Images