JP2007049015A - Electronic device structure and electronic device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic device structure which insulates heat between the periphery of a heat generating component and the periphery of a component except for the heat generating component. <P>SOLUTION: The electronic device structure insulates heat by disposing a heat insulating material 1 between the peripheries of heat generating components 3, 4 and the periphery of a component 5 other than the heat generating components 3, 4 in such a manner that the component 5 other than the heat generating components 3, 4 positioned on an identical circuit board 2 can be avoided from being exposed to heat, and heat from the heat generating components 3, 4 can be locally entrapped. The electronic components 3, 4 are electromagnetic wave radiating components, and the heat insulating material 1 is an electromagnetic wave shielding material. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structure of an electronic device.

  In recent electronic devices, heat generating components such as a large processing integrated circuit (LSI) such as a central processing unit (CPU) and a memory, a power device such as a power amplifier (PA), and a field effect transistor (FET) are used. As a method for dealing with problems caused by heat generation of these parts, for example, a problem that a user feels uncomfortable due to a high temperature of a contact portion with a human body in a notebook personal computer, methods such as Patent Documents 1 and 2 described later have been proposed. ing.

  In Patent Document 1, a thin, high-performance vacuum heat insulating material is attached between a substrate heat generating part inside a personal computer and the surface of the personal computer in close contact with a limited size so as to improve thermal insulation efficiency. A method has been proposed that suppresses the overall temperature rise and does not cause discomfort to the user.

  In Patent Document 2, the printed circuit board and keyboard, Hard Disk Drive (HDD), aluminum ground plate, and the case of the main body are surrounded by a heat insulating material, and further, by a heat pipe connected to a heat source. A method of guiding heat to a heat radiation place to dissipate heat is disclosed.

JP 2003-29878 A JP-A-11-202978

  However, in the conventional method as shown in the above-mentioned patent document, the heat source and the housing are arranged so that heat is not transmitted to the housing that is a human body contact portion of the electronic device, in order to avoid discomfort to the user. A heat insulating material is disposed between them, or a heat insulating material is disposed so as to surround the entire circuit board on which a heat generating component such as a CPU is disposed.

  For this reason, parts other than the heat-generating parts arranged on the same circuit board are surrounded by a heat insulating material together with the heat-generating parts, and are exposed to the heat of the heat-generating parts.

  Therefore, in view of such problems, the present invention has an object to provide an electronic device structure that locally contains heat from a heat-generating component on a circuit board and reduces heat conduction to other components on the circuit board. .

  In order to solve the above-described problems, the electronic device structure of the present invention is characterized in that it has a structure that blocks heat between the periphery of the heat generating component and the periphery of the component excluding the heat generating component.

  The electronic device structure according to claim 1 of the present invention is an electronic device including a plurality of components, one part of which is a heat generating component, between the periphery of the heat generating component and the periphery of the component excluding the heat generating component. It is characterized by having a structure that blocks heat.

  Furthermore, the electronic device structure according to claim 2 of the present invention is characterized in that, in claim 1, the structure for blocking heat is a heat insulating material.

  Furthermore, the electronic device structure according to claim 3 of the present invention is characterized in that, in claim 2, the heat insulating material is arranged around the heat generating component and the periphery of the heat generating component.

  Furthermore, the electronic device structure according to claim 4 of the present invention is characterized in that, in claim 2, the heat insulating material is disposed in a part excluding the heat generating part and in a periphery of the part excluding the heat generating part. To do.

  Furthermore, an electronic equipment structure according to a fifth aspect of the present invention is characterized in that, in the third to fourth aspects, the periphery includes a part of a circuit board.

  The electronic device structure according to claim 6 of the present invention is the circuit board according to claim 1, wherein the structure for blocking heat is between the periphery of the heat generating component and the periphery of the component excluding the heat generating component. It is the structure in.

  Furthermore, the electronic device structure according to claim 7 of the present invention is the structure according to claim 6, wherein the structure of the circuit board is a structure in which the heat generating component and a component excluding the heat generating component are arranged on different circuit boards. It is characterized by.

  The electronic device structure according to claim 8 of the present invention is characterized in that in claim 7, at least one of the heat generating component and the circuit board on which the heat generating component is arranged is covered with a heat insulating material.

  Furthermore, the electronic device structure according to claim 9 of the present invention covers, in claim 7, at least one of the component excluding the heat generating component and the circuit board on which the component excluding the heat generating component is disposed with a heat insulating material. It is characterized by that.

  The electronic device structure according to claim 10 of the present invention is the structure according to claim 6, wherein the structure of the circuit board is a structure in which at least one of the wiring pattern widths of the power supply layer or the ground layer of the circuit board is narrowed. It is characterized by being.

  Furthermore, an electronic device structure according to an eleventh aspect of the present invention is the electronic device structure according to the sixth aspect, wherein the structure of the circuit board is a structure perforated in the circuit board.

  Furthermore, an electronic device structure according to a twelfth aspect of the present invention is the electronic device structure according to the sixth aspect, wherein the structure of the circuit board is one of the circuit boards between a place where the heat generating component is disposed and a place excluding the place. The structure is characterized in that the part is removed.

  The electronic device structure according to claim 13 of the present invention is the circuit board circuit according to claim 6, wherein the structure of the circuit board is a circuit between the place where the heat generating component is disposed and the place excluding the place. The structure is characterized in that a part of the substrate layer is removed.

  Furthermore, an electronic device structure according to a fourteenth aspect of the present invention is characterized in that in any one of the tenth to thirteenth aspects, at least one of the heat generating component and the periphery of the heat generating component is covered with a heat insulating material.

  Furthermore, the electronic device structure according to claim 15 of the present invention is characterized in that at least one of a component excluding the heat generating component and a periphery of the component excluding the heat generating component is covered with a heat insulating material.

  Furthermore, an electronic device structure according to a sixteenth aspect of the present invention is the electronic device structure according to the first to fifteenth aspects, wherein the heat generating component is a component that emits electromagnetic waves, and the heat insulating material is an electromagnetic wave shielding material.

  Furthermore, an electronic device according to a seventeenth aspect of the present invention is characterized by having at least one structure according to the first to sixteenth aspects.

  In addition, the present invention can be applied to a desktop personal computer, a measuring device, or a portable electronic device such as a personal digital assistance (PDA) or a notebook personal computer, and an electronic device including a mobile phone.

As described above, the electronic device structure and the electronic device of the present invention are characterized in that they have a structure that blocks heat between the periphery of the heat generating component and the periphery of the component excluding the heat generating component.
As a result, it is possible to prevent the heat from the heat generation point in the electronic device from being transmitted to other than the heat generation point and causing a problem.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing the structure of an electronic device showing a first embodiment of the present invention. In FIG. 1, reference numeral 2 denotes a circuit board such as a printed circuit board that is usually housed in a housing (not shown). Reference numerals 3, 4, and 5 denote ICs and LSIs mounted on the circuit board 2, and further electronic parts such as PAs and FETs. 1 shows a heat insulating material. Here, the arrow symbol attached | subjected to the heat insulating material 1 is demonstrated. In this embodiment, the heat insulating material 1 is disposed so as to be closer to the circuit board 2 and the components 3 and 4. However, in FIG. 1, for the sake of explanation, they are shown separated upward. The arrow symbol attached | subjected to the heat insulating material 1 shows that the heat insulating material 1 is illustrated in the position different from an original position for description as mentioned above.

  Further, in FIG. 1 and the drawings of the following embodiments, the heat insulating material 1 on a flat plate is shown in the figure, but the heat insulating material 1 may have other shapes. For example, it may have a box shape or a frame shape so as to cover and cover the parts 3 and 4 from above. Furthermore, it is not necessary to be one kind of material having heat insulating properties. For example, the heat insulating property may be realized by the structure, such as the one having a vacuum structure or the one in which a liquid is injected. Moreover, you may implement | achieve heat insulation with the combination of a some member, or its combination structure. For example, a material that has heat insulating properties but does not have sufficient mechanical strength by itself when solidified may be applied to the structural member to realize the heat insulating properties. That is, the present invention is effective even with a heat insulating component or a heat insulating member. Below, it demonstrates as a case where a heat insulating material is used. As the heat insulating material, there are materials such as calcium silicate and ceramic fiber.

  Here, it is assumed that the components 3 and 4 are components that generate heat depending on the operation state. In the present embodiment, as shown in FIG. 1, only the vicinity of the circuit board 2 where the components 3 and 4 are arranged is covered with the heat insulating material 1. Thereby, the heat generated from the components 3 and 4 is blocked or reduced by the heat insulating material 1. Without the heat insulating material 1, the heat of the parts 3 and 4 is conducted and diffused through various paths. For example, heat is conducted by convection of a gas in the casing or the casing which is not shown. In the process in which heat is conducted by the casing, the temperature of the casing itself rises. For example, when a portion of the user's human body that touches the casing, such as a portable terminal, becomes hot, the user is uncomfortable. Various problems also occur when heat is transmitted to other components on the circuit board shown in the component 5. For example, in a component whose operation characteristics are sensitive to changes in the ambient temperature, problems such as operation becoming unstable due to an increase in ambient temperature and the inability to obtain predetermined characteristics occur. Furthermore, use under high temperature conditions degrades the part and shortens the life of the part in the long term.

  In the conventional method of applying heat insulating material to the inside of the housing in a form corresponding to the entire circuit board, or covering the entire circuit board with heat insulating material, all the parts on the circuit board are covered with the heat insulating material together with the heat generating parts. It will be. In such a case, since the other components on the circuit board are exposed to the heat of the heat generating component, the above-described problem occurs.

  Here, if the heat-generating component is simply covered with the heat insulating material, the heat is generated by the heat insulating material, causing a problem that it is not dissipated. To solve this problem, heat may be guided to a different location with a heat conducting material to dissipate it. You can escape. For example, as in the first embodiment, the design may be designed such that the lower part of the circuit board is intentionally opened and heat is released together with the structure of the casing not shown.

  In particular, in portable electronic devices, it may not be necessary to consider heat radiation. This is because in a portable electronic device, power saving is performed to extend the operation time of the battery. Due to the power saving, the operation time during which a component whose power consumption is increased generates heat is shortened as much as possible. Therefore, the heat generating component generates heat for a limited time during the operation of the electronic device. If the heat generation of the component is limited for a short time or intermittently, it is not necessary to consider that the heat is actively released. The heat of the heat-generating component is averaged by the heat conduction being delayed by the heat insulating material. Thereby, it is possible to surpass a short heat generation time. For this reason, the above-mentioned problems are solved or reduced.

FIG. 2 and FIG. 3 show an example of thermal conduction delay when a heat insulating material is used. It is a simulation result in the case where the heat generating component and the housing 13 in the electronic device are assumed and the heat insulating material is disposed between the heat generating component and the housing 13 and when the heat insulating material is not disposed. FIG. 2 shows a case where a heat insulating material is not arranged, and FIG. 3 shows a case where a heat insulating material is arranged. The heat insulating material is assumed to have a thermal conductivity of 0.03 W / mK or less, a thickness of 1 mm or more, and a density of 3000 kg / m ³ . Temporal changes in temperature are moderated by the arrangement of the heat insulating material. Here, FIGS. 2 and 3 are calculated on the assumption of the housing surface temperature, and therefore, supplementation will be made assuming the problem of user discomfort. When the body temperature exceeds 36 ° C., it is assumed that the human body is hotter and the user feels uncomfortable. Comparing the time when the housing surface temperature becomes 36 ° C., it takes about 375 seconds in FIG. 2, but it takes about 750 seconds in FIG. That is, in the time required for the housing surface temperature to reach 36 ° C., the heat conduction is delayed by about twice due to the arrangement of the heat insulating material.

  In addition, the effect of averaging due to the delay in heat conduction by the heat insulating material described above applies to all cases where the heat insulating material is used in the following examples.

  A second embodiment will be described with reference to FIG. In the following description after the present embodiment, a redundant description of portions having the same contents as those of the first embodiment will be omitted, and description will be made focusing on portions different from the first embodiment.

  In the second embodiment, the heat insulating material 1 is arranged above and below the circuit board 2, and a part of the circuit board 2 around the components 3 and 4 is covered from above and below.

  When the components 3 and 4 are heat generating components, the heat generating portions on the circuit board 2 on which the heat generating components are arranged are covered with the heat insulating material from above and below. For this reason, a housing (not shown) is also arranged below the circuit board 2 to prevent heat conduction from the housing under the circuit board and conduction of heat to the housing itself. It becomes.

  A third embodiment will be described with reference to FIG.

  In the third embodiment, the heat insulating material 1 is arranged above and below the circuit board 2, and a part of the circuit board 2 around the component 5 is covered from above and below.

  In the third embodiment, heat from the heat generating component 3 or 4 is prevented from being transmitted to the component 5 on the same circuit board via a housing or the like not shown. Thereby, the heat of the heat generating components 3 and 4 is radiated without being insulated, but it is possible to prevent the radiated heat from being conducted to the component 5 and causing a problem.

  Here, if the heat conduction to the component 5 mainly passes above the circuit board 2, the heat insulating material 1 below the circuit board 2 may not be disposed. The case of conducting heat from above is, for example, the case where a heat generating component is mounted on the upper side of the circuit board. An LSI or the like having a radiation fin at the top has a structure in which the component itself dissipates heat upward rather than on the mounted circuit board side (downward). Therefore, the tendency for heat to be transmitted from above becomes particularly remarkable.

  A fourth embodiment will be described with reference to FIG.

  In the fourth embodiment, the heat generating components 3 and 4 and the component 5 are divided into 2 and 6 which are separate circuit boards. The circuit boards 2 and 6 are connected to each other by a cable 7. The cable 7 is, for example, a flexible print cable (FPS) or a flat cable. In this embodiment, since the heat generating component is separated from the entire circuit board and covered with a heat insulating material, heat conduction and diffusion can be further prevented as compared with the case where the heat generating component is mounted on the same circuit board. This is because the heat generating part is physically separated and covered more completely with a heat insulating material, and heat conduction by the circuit board is prevented by using a cable. However, in this embodiment, a heat insulating material that is vertically or omnidirectional is not necessarily required. In the same manner as in the third embodiment, a heat insulating material may be provided where necessary according to the heat conduction factor and path.

  An example of a portable electronic device using this embodiment is shown in FIG. FIG. 7 shows that the circuit board including the heat-generating component is completely covered with a heat insulating material and housed in the housing.

  A fifth embodiment will be described with reference to FIG.

  In the fifth embodiment, similar to the fourth embodiment, the heat generating components 3 and 4 and the component 5 are divided into 2 and 6 which are separate circuit boards. The difference from the fourth embodiment is that, in this embodiment, the heat generating component and its surroundings are not covered with a heat insulating material, but the heat insulating component 5 and its surroundings are covered with a heat insulating material. The component 5 is separated from the heat generating components 3 and 4 and the circuit board and is covered with a heat insulating material. Therefore, the heat conducted by the circuit board and the heat conducted via the housing (not shown) can be further prevented.

  However, in this embodiment, a heat insulating material that is vertically or omnidirectional is not necessarily required. In the same manner as in the third embodiment, a heat insulating material may be provided where necessary according to the heat conduction factor and path.

  A sixth embodiment will be described with reference to FIG.

  Reference numeral 8 in FIG. 9 shows an image of a wiring pattern of the circuit board 2, particularly a power supply and a ground. In FIG. 9, the circuit board 2 and the wiring pattern 8 are shown in the drawing. The wiring pattern 8 shows the internal structure of the circuit board 2, and the wiring pattern 8 is physically separated from the circuit board 2. Does not exist. A broken-line frame indicated by 9 in FIG. 9 indicates a boundary location on the circuit board between the location where the heat generating components 3 and 4 are arranged and the location of the component 5.

  In the sixth embodiment, the power supply or ground wiring pattern at the boundary 9 on the circuit board 2 is narrowed down as 10 or 11 shown in the figure. In a printed circuit board or the like, since copper or the like is used for the wiring pattern, the thermal conductivity is high. In particular, the power supply and ground patterns are often designed so that wiring is performed over a wide area for noise suppression and circuit stabilization. In the present embodiment, the conduction of heat can be suppressed by deliberately narrowing the power supply and ground patterns designed in a particularly large area. Since the present embodiment does not use a plurality of circuit boards and additional parts such as cables and connectors for connecting the circuit boards as in the seventh and eighth embodiments, there are advantages that the cost of parts and the number of assembly steps are small. There is.

  In addition, although a heat insulating material is not shown in a present Example, a present Example can improve an effect more in combination with another Example also including the Example using a heat insulating material.

  A seventh embodiment will be described with reference to FIG.

  Reference numeral 12 in FIG. 10 denotes a hole formed in the circuit board. With this hole, it is possible to reduce the contact surface of the circuit board 2 where the heat generating components 2 and 3 are disposed and the contact surface where the component 5 is disposed, thereby reducing the amount of heat conduction of the substrate material itself. Further, as in the sixth embodiment, additional components such as a plurality of circuit boards, cables and connectors for connecting the circuit boards are not used, and therefore there is an advantage that the cost of parts and the number of assembly steps are reduced.

  The hole 12 does not necessarily have to penetrate, but it is desirable to penetrate. This is because the contact surface that conducts heat is further reduced.

  Needless to say, the wiring pattern of the circuit board 2 is designed in accordance with the provision of the holes 12.

  In addition, this embodiment can be combined with other embodiments as appropriate to enhance the effect.

  An eighth embodiment will be described with reference to FIG.

  FIG. 11 shows that a part of the connection place on the circuit board 2 at the place where the heat generating components 3 and 4 are arranged and the place where the part 5 is arranged on the circuit board 2 is removed. By removing a part of the substrate, the connection surface that conducts heat is reduced as in the seventh embodiment, and the heat conducted from the heat generating portion can be reduced.

  Although this is a modified circuit board, since there are no additional parts such as a plurality of circuit boards and cables and connectors for connecting the circuit boards as in the sixth embodiment, there are advantages that the cost of parts and assembly man-hours are small.

  A ninth embodiment will be described with reference to FIG.

  FIG. 12 shows that a part of the substrate layer on the circuit board 2 at the place where the heat generating components 3 and 4 and the part 5 are arranged on the circuit board 2 is removed. Show. By removing a part of the substrate layer, the connection surface that conducts heat is reduced as in the seventh embodiment, and the heat conducted from the heat generating portion can be reduced.

  Although it is a special board, it does not use a plurality of circuit boards or additional parts such as cables and connectors for connecting the circuit boards as in the case of the sixth embodiment.

  In addition, this embodiment can be combined with other embodiments as appropriate to enhance the effect.

  As described above, the electronic device structure and the electronic device of the present invention are characterized in that they have a structure that blocks heat between the periphery of the heat generating component and the periphery of the component excluding the heat generating component. As a result, it is possible to prevent the heat from the heat generation point in the electronic device from being transmitted to other than the heat generation point and causing a problem.

The block diagram in the form of Example 1 of this invention The figure which shows the experimental result of the surface temperature change of a heating element and a case (without heat insulation) The figure which shows the experimental result of the surface temperature change of a heating element and a case (with heat insulating material) The block diagram in the form of Example 2 of this invention The block diagram in the form of Example 3 of this invention The block diagram in the form of Example 4 of this invention The block diagram of the portable electronic device corresponding to the form of Example 4 of this invention The block diagram in the form of Example 5 of this invention The block diagram in the form of Example 6 of this invention The block diagram in the form of Example 7 of this invention The block diagram in the form of Example 8 of this invention The block diagram in the form of Example 9 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat insulating material 2 Circuit board 3 Component 4 Component 5 Component 6 Circuit substrate 7 Cable 8 Wiring pattern 9 Boundary 10 Pattern width 11 Pattern width 12 Hole 13 Case

Claims (17)

An electronic device including a plurality of parts, some of which are heat generating parts,
An electronic device structure having a structure that blocks heat between a periphery of the heat generating component and a periphery of the component excluding the heat generating component. The electronic device structure according to claim 1, wherein the heat blocking structure is a heat insulating material. The electronic device structure according to claim 2, wherein the heat insulating material is disposed around the heat generating component and the periphery of the heat generating component. The electronic device structure according to claim 2, wherein the heat insulating material is disposed around a component excluding the heat generating component and around a component excluding the heat generating component. 5. The electronic device structure according to claim 3, wherein the periphery includes a part of a circuit board. The electronic device structure according to claim 1, wherein the structure for blocking heat is a structure on a circuit board between a periphery of the heat generating component and a periphery of the component excluding the heat generating component. The structure on the circuit board is:
The heat generating component;
The electronic device structure according to claim 6, wherein the electronic device structure has a structure in which components excluding the heat-generating component are arranged on different circuit boards. 8. The electronic device structure according to claim 7, wherein at least one of the heat generating component and the circuit board on which the heat generating component is disposed is covered with a heat insulating material. 8. The electronic device structure according to claim 7, wherein at least one of a component excluding the heat generating component and a circuit board on which the component excluding the heat generating component is arranged is covered with a heat insulating material. The structure on the circuit board is:
The electronic device structure according to claim 6, wherein at least one wiring pattern width of the power supply layer or the ground layer of the circuit board is narrowed. The electronic device structure according to claim 6, wherein the structure of the circuit board is a structure perforated in the circuit board. The electronic device structure according to claim 6, wherein a structure of the circuit board is a structure in which a part of the circuit board is removed between a place where the heat generating component is disposed and a place excluding the place. The electronic device structure according to claim 6, wherein a structure of the circuit board is a structure in which a part of a circuit board layer of the circuit board between a place where the heat generating component is disposed and a place excluding the place is removed. . 14. The electronic device structure according to claim 10, wherein at least one of the heat generating component and the periphery of the heat generating component is covered with a heat insulating material. 15. The electronic device structure according to claim 10, wherein at least one of a component excluding the heat generating component and a periphery of the component excluding the heat generating component is covered with a heat insulating material. The electronic device structure according to claim 1, wherein the heat generating component is a component that radiates electromagnetic waves, and the heat insulating material is an electromagnetic wave shielding material. An electronic apparatus comprising at least one structure according to claim 1.

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