JP2010165252A - Electronic appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic appliance for effectively preventing an increase in temperature of a case. <P>SOLUTION: The electronic appliance includes a first metal case 21, a second case 22 disposed independently of the first case 21, and a boss part 31 that is positioned adjacent to a heat generating component, and protrudes from the first case 21 toward the second case 22 in an integrated fashion. The electronic appliance further includes a printed circuit board 23 that is sandwiched between the boss part 31 and the second case 22 and on which the heat generating component is mounted, a fixing member that is fixed to the boss part 31 so as to fix the second case 22 to the first case 21 while penetrating the second case 22 and the printed circuit board 23, and a resin spacer 27 disposed between the printed circuit board 23 and the boss part 31. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic device in which a printed circuit board is disposed between a first case and a second case.

  An electronic device having a printed circuit board fixed to a case is disclosed. The electronic device includes a case, a boss part protruding from the case, a printed circuit board supported by the boss part inside the case, and a screw for fixing the printed circuit board to the boss part. Have. The case has a screw hole provided in the boss portion and a heat dissipation through hole provided around the screw hole. Further, the printed circuit board has a screw hole through which a screw is passed and a ventilation hole provided around the screw hole.

  In the general electronic device as described above, heat generated from the CPU or the like is transmitted to the screw via a printed circuit board and air. The heat transferred to the screw is transferred to the boss portion and raises the temperature around the boss portion. In this electronic device, heat can be released from the boss portion to the outside through the through hole and the ventilation hole, and thereby the temperature of the case can be lowered (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 10-98288

  By the way, in the said electronic device, although synthetic resin is common as a material of a case, a case may be formed using a metal material with high heat conductivity. At this time, the boss portion is formed integrally with the case by a metal material. In such an electronic device, since the thermal conductivity is increased in the boss portion, the temperature rise of the case cannot be sufficiently suppressed simply by providing a through hole or a vent hole. For this reason, in the structure of the above-mentioned conventional electronic device, it cannot be said that it is effective even when the case is made of metal, and there is room for improvement.

  The objective of this invention is providing the electronic device which can prevent the temperature rise of a case effectively.

  In order to achieve the above object, an electronic apparatus according to an aspect of the present invention includes a first case made of metal, a second case provided independently of the first case, and the second case. Projecting integrally from the first case toward the case, and sandwiched between the boss portion located in the vicinity of the heat generating component, the boss portion and the second case, and mounted with the heat generating component A printed circuit board, a fixing member that is fixed to the boss portion so as to pass through the second case and the printed circuit board and fix the second case to the first case, and the printed circuit board. And a resin spacer provided at a position between the boss portion.

  According to said structure, the electronic device which can prevent the temperature rise of a case effectively can be provided.

1 is a perspective view showing a portable computer according to a first embodiment. The bottom view which shows the portable computer shown in FIG. 1 from the downward direction. FIG. 2 is an enlarged sectional view showing a peripheral structure of a spacer of the portable computer shown in FIG. 1. The perspective view which showed the spacer shown in FIG. 3 from diagonally upward. The perspective view which showed the spacer shown in FIG. 4 from the different angle. Sectional drawing which expands and shows the peripheral structure of the spacer of the portable computer which concerns on 2nd Embodiment. Sectional drawing which expands and shows the peripheral structure of the spacer of the portable computer which concerns on 3rd Embodiment.

  Below, with reference to FIGS. 1-5, 1st Embodiment of an electronic device is described. In this specification, the front side (ie, the user side) is front, the back side is viewed from the user, the left side is viewed from the user, the left side is viewed from the user, the right side is viewed from the user, the right side is viewed from the user, and the top is viewed from the user. The downward direction is defined as the bottom.

  As shown in FIG. 1, a portable computer 11, which is an example of an electronic device, includes a main body unit 12, a display unit 13, and a hinge portion 14 provided between the main body unit 12 and the display unit 13. . The hinge portion 14 supports the display unit 13 and can rotate the display unit 13 with respect to the main unit 12. The display unit 13 includes a display 15 configured by a liquid crystal display and a cover 16 surrounding the display 15.

  As shown in FIGS. 1 to 3, the main unit 12 includes a housing 20 having a first case 21 and a second case 22, a printed circuit board 23 accommodated in the housing 20, and a housing. 20, a keyboard 24 and a touch pad 25, and a screw 26 that is a fixing member for fixing the second case 22 to the first case 21. The main unit 12 further includes a spacer 27, and the spacer 27 is interposed around the screw 26 at a position between a boss portion 31 (to be described later) of the first case 21 and the printed circuit board 23.

  As shown in FIG. 3, the printed circuit board 23 is sandwiched and fixed between the boss portion 31 and the second case 22. The printed circuit board 23 includes a printed wiring board 32, various components mounted on the printed wiring board 32, and a plurality of heat generating components. The heat generating component includes, for example, a CPU 33 (central processing unit) shown in FIG. 2, a north bridge, a graphics chip, etc. (not shown). Various components include, for example, various random access memories (RAMs), read only memories (ROMs), and the like. The printed wiring board 32 is a copper-clad laminate in which a plurality of copper wiring layers are laminated. The printed wiring board 32 includes a first hole 32A through which the screw 26 is passed, and a ground conductor pattern (not shown) provided along the edge of the first hole 32A. The printed circuit board 23 can be grounded to the housing 20 through this conductor pattern.

  As shown in FIG. 3, the second case 22 forms the upper half of the housing 20, and is formed of, for example, a synthetic resin. The second case 22 is provided independently of the first case 21. On the second case 22, a keyboard 24 and a touch pad 25, which are operation units, are attached. The material of the second case 22 is not limited to synthetic resin, and may be formed of a metal material such as a magnesium alloy, for example. As shown in FIGS. 1 and 3, the second case 22 further includes a palm rest portion 35 provided at a position in front of the keyboard 24 and a second hole provided in the vicinity of an attachment portion to which the keyboard 24 is attached. 22A. This palm rest part 35 is a place where the palm of the user who uses the keyboard 24 is placed. A screw 26 is passed through the second hole 22A.

  As shown in FIG. 3, the first case 21 forms the lower half of the housing 20 and is formed of a metal material such as a magnesium alloy, for example. The first case 21 includes a case main body 30 and a boss portion 31 formed so as to protrude integrally from the case main body 30 toward the second case 22. As shown in FIG. 2, the boss 31 is provided in the vicinity of the CPU 33 that is a heat generating component. In the present embodiment, the boss portion 31 is disposed in the vicinity of the keyboard 24 that is an operation portion.

  As shown in FIG. 3, the boss portion 31 has a substantially cylindrical shape or frustum shape that is slightly narrowed toward the tip. The boss part 31 has a fixing hole 36 that is a screw hole to which the screw 26 is fixed, and a hooking part 38 to which an engaging part 37 to be described later of the spacer 27 is hooked. The screw 26 passes through the second case 22 and the printed circuit board 23 and is fixed to the fixing hole 36. The hook portion 38 includes a recess 38A into which the frame-like engagement portion 37 is fitted, and a projection 38B that fits inside the through hole 45 of the engagement portion 37.

  As shown in FIGS. 3 to 5, the spacer 27 covers the cylindrical spacer body 41, the conductive ground layer 42 provided on the surface of the spacer body 41, and the tip of the boss portion 31. A cap part 43 extending from the lower end of the spacer body 41 and an engaging part 37 forming a part of the cap part 43 are provided. A rotation stopping mechanism 44 is provided between the boss portion 31 and the spacer 27, and the rotation stopping mechanism 44 prevents the spacer main body 41 from rotating with respect to the boss portion 31.

  The spacer main body 41, the cap part 43, and the engaging part 37 are integrally formed of synthetic resin. The ground layer 42 electrically connects the first case 21 and the printed circuit board 23. The ground layer 42 is provided across the inner peripheral surface 41 </ b> A of the spacer body 41 and both end faces 41 </ b> B at both end portions in the axial direction of the spacer body 41. The ground layer 42 is made of, for example, a metal layer such as nickel, and is formed by subjecting the inner peripheral surface 41A of the spacer body 41 to electroless nickel plating. Prior to the plating of the ground layer 42, the inner peripheral surface 41A of the spacer body 41 is masked so that the ground layer 42 is not formed on the inner peripheral surface 41A.

  The cap portion 43 has a shape along the tip of the boss portion 31 and has a tapered shape that expands as it goes downward. The engaging portion 37 is formed as a part of the cap portion 43 and has a flat plate shape extending obliquely downward from the lower end of the spacer body 41. The engaging portion 37 has a through hole 45 provided at the center thereof and a frame portion 46 that defines the periphery of the through hole 45. The protrusion 38 </ b> B of the hook portion 38 can be fitted into the through hole 45.

  The rotation stop mechanism 44 includes a slit 47 provided in a part of the cap portion 43 and a rib 48 that integrally protrudes from the periphery of the boss portion 31 in the radial direction of the boss portion 31. The slit 47 is provided at a position 180 degrees opposite to the position where the engaging portion 37 is provided. The slit 47 is formed so as to rise upward from the lower end of the cap portion 43. The slit 47 has a chamfered portion 47B near the end opposite to the inner portion 47A, and the chamfered portion 47B has a corner near the end so as to form a gentle arc at the end. Taken and formed. For this reason, the width | variety of the slit 47 becomes large as it goes to an end near part.

  In the rotation stopping mechanism 44 of the present embodiment, the slit 47 is provided in a part of the cap portion 43 and the rib 48 is provided around the boss portion 31. However, the present invention is not limited to this. The rotation prevention mechanism 44 is configured by a slit provided on the peripheral surface of the boss portion 31 and recessed in a groove shape, and a rib that protrudes in the center direction from the inner peripheral portion of the cap portion 43 and fits into the slit. Also good.

  Next, a method for fixing the printed circuit board 23, the first case 21, and the second case 22 using the spacer 27 will be described. First, as shown in FIG. 3, the spacer 27 is attached to the boss portion 31 of the first case 21. At this time, the slit 47 is aligned with the position of the rib 48 so that the cap portion 43 of the spacer 27 covers the tip of the boss portion 31. At the same time, the engaging portion 37 is hooked on the hook portion 38 of the boss portion 31. Next, the printed circuit board 23 and the second case 22 are installed from above the spacer 27. Finally, the screw 26 is passed through the second hole 22A of the second case 22 and the first hole 32A of the printed circuit board 23 so that the screw 26 is fastened to the fixing hole 36 of the boss portion 31. . Thus, the assembly of the main unit 12 is completed.

  According to the first embodiment, the portable computer 11 includes a first case 21 made of metal, a second case 22 provided independently of the first case 21 and including an operation unit, Projecting integrally from the first case 21 toward the second case 22 and being sandwiched between the boss 31 located near the heat generating component and the boss 31 and the second case 22 A mounted printed circuit board 23, a fixing member fixed to the boss 31 so as to pass through the second case 22 and the printed circuit board 23 and fix the second case 22 to the first case 21, and a printed circuit And a resin spacer 27 interposed around the fixing member at a position between the plate 23 and the boss portion 31.

  According to this configuration, since the resin spacer 27 is interposed between the boss portion 31 and the printed circuit board 23, the temperature rises in the boss portion 31 of the first case 21 made of metal having good thermal conductivity. When this occurs, the heat can be prevented from being transmitted to the printed circuit board 23 and the second case 22. This is particularly effective in that the temperature rise of the second case 22 having the operation unit, which is a part touched by the user, can be prevented. In addition, it is possible to effectively prevent the occurrence of a problem that heat is accumulated in the printed circuit board 23.

  At this time, the spacer 27 is provided on the surface of the spacer body 41 having a cylindrical shape, and the conductive ground layer 42 that electrically connects the first case 21 and the printed circuit board 23. And having. According to this configuration, the ground layer 42 can reliably ground the printed circuit board 23 and the first case 21. Thereby, for example, it is possible to prevent leakage of electromagnetic waves emitted from components on the printed circuit board 23 to the outside of the first case 21 and the second case 22 as much as possible.

  The ground layer 42 is provided across the inner peripheral surface 41 </ b> A of the spacer body 41 and both end faces 41 </ b> B of the spacer body 41. Usually, the ground layer 42 is formed of a metal material having good thermal conductivity. According to the above configuration, the area of the ground layer 42 can be made smaller than when the ground layer 42 is provided on the entire surface of the spacer body 41. Thereby, the thermal conductivity in the spacer 27 can be lowered, and the heat of the first case 21 can be prevented from being efficiently transmitted to the printed circuit board 23 and the second case 22.

  The spacer 27 has a cap portion 43, and the cap portion 43 extends from the spacer body 41 so as to cover the tip of the boss portion 31. According to this configuration, the spacer 27 can be easily attached to the boss portion 31 so as to cover the boss portion 31 with the cap portion 43. The spacer 27 has an engaging portion 37, and the engaging portion 37 is hooked on a hook portion 38 provided on the boss portion 31. According to this, it can prevent that the spacer 27 remove | deviates from the boss | hub part 31 arbitrarily.

  At this time, the engaging portion 37 forms a part of the cap portion 43. According to this configuration, the structure of the spacer 27 can be simplified as compared with the case where the engaging portion 37 is provided separately from the cap portion 43. The portable computer 11 includes a slit 47 provided in one of the cap part 43 and the boss part 31, and a rib 48 provided in either the cap part 43 and the boss part 31 and fitted inside the slit 47. Are further provided. According to this configuration, a structure for preventing rotation of the spacer 27 can be formed between the cap portion 43 and the boss portion 31, thereby preventing the spacer 27 from freely rotating with respect to the boss portion 31. be able to. Therefore, it is possible to prevent problems such as the ground conductor pattern on the printed circuit board 23 being scraped by the rotation of the spacer 27.

  The width of the slit 47 becomes wider as it goes closer to the end on the opposite side of the slit 47 from the inner portion 47A. According to this configuration, even if the slit 47 and the rib 48 are provided, the rib 48 can be easily fitted into the slit 47. For this reason, when covering the front-end | tip of the boss | hub part 31, the spacer 27 can prevent these from interfering with mounting | wearing.

  The second case 22 has a palm rest part 35 provided in front of the operation part, and the spacer 27 is provided in the vicinity of at least one of the operation part and the palm rest part 35. According to this configuration, an increase in the temperature of the second case 22 can be effectively prevented in the vicinity of the operation unit and the palm rest unit 35, which are portions where the user's hand contacts. The ground layer 42 is a metal layer formed by plating the spacer body 41. According to this configuration, the ground layer 42 that is as thin as possible can be formed easily and inexpensively. If the thin ground layer 42 is formed as much as possible, it is possible to prevent the heat transferability of the spacer 27 from increasing.

  Next, a second embodiment of the portable computer will be described with reference to FIG. In the portable computer 11 which is an example of the electronic apparatus of the second embodiment, the boss portion 31 is provided in the vicinity of the palm rest portion 35 of the second case 22 and the ground layer 42 of the spacer 27 is formed. Although the position is different from that of the first embodiment, the other parts are the same as those of the first embodiment. For this reason, mainly different parts will be described, and common parts will be denoted by common reference numerals and description thereof will be omitted.

  The spacer 27 includes a cylindrical spacer body 41, a conductive ground layer 42 provided on the surface of the spacer body 41, and a cap portion extending from the lower end of the spacer body 41 so as to cover the tip of the boss portion 31. 43 and an engaging portion 37 that is hooked by a hooking portion 38 provided in the boss portion 31. A rotation stopping mechanism 44 is provided between the boss portion 31 and the spacer 27, and the rotation stopping mechanism 44 prevents the spacer main body 41 from rotating with respect to the boss portion 31.

  The spacer body 41 is made of synthetic resin. As shown in FIG. 6, the ground layer 42 is provided across the outer peripheral surface 41 </ b> C of the spacer body 41 and both end faces 41 </ b> B at both end portions in the axial direction of the spacer body 41. The ground layer 42 is a metal layer formed by plating nickel or the like on the outer peripheral surface 41C and both end surfaces 41B of the spacer body 41.

  According to the present embodiment, the ground layer 42 is provided across the outer peripheral surface 41 </ b> C of the spacer body 41 and both end faces of the spacer body 41. According to this configuration, the area of the ground layer 42 can be reduced as compared with the case where the ground layer 42 is provided on the entire surface of the spacer body 41. Thereby, the thermal conductivity in the spacer 27 can be lowered, and the heat of the first case 21 can be prevented from being efficiently transmitted to the printed circuit board 23 and the second case 22.

  Next, a third embodiment of the portable computer will be described with reference to FIG. The portable computer 11 which is an example of the electronic device of the third embodiment is different from that of the first embodiment in that the ground layer 42 of the spacer 27 is different, but the other parts are the first. This is common to the first embodiment. For this reason, mainly different parts will be described, and common parts will be denoted by common reference numerals and description thereof will be omitted.

  The spacer 27 includes a cylindrical spacer body 41, a conductive ground layer 42 provided on the surface of the spacer body 41, and a cap portion extending from the lower end of the spacer body 41 so as to cover the tip of the boss portion 31. 43 and an engaging portion 37 that is hooked on a hooking portion provided on the boss portion 31. A rotation stop mechanism 44 is provided between the boss portion 31 and the spacer 27.

  The spacer body 41 is made of synthetic resin. As shown in FIG. 7, the ground layer 42 includes the entire circumference of the spacer main body 41, that is, the inner peripheral surface 41 </ b> A and the outer peripheral surface 41 </ b> C of the spacer main body 41, and both end surfaces 41 </ b> B at both end portions in the axial direction of the spacer main body 41. , It is provided to span. The ground layer 42 is a metal layer formed by plating nickel or the like around the entire circumference of the spacer body 41.

  According to the third embodiment, since the ground layer 42 is formed on the entire circumference of the spacer body 41, the reliability of electrical connection between the printed circuit board 23 and the first case 21 is improved. be able to. For this reason, the printed circuit board 23 can be reliably grounded with respect to the first case 21, and electromagnetic waves emitted from components on the printed circuit board can be prevented from leaking to the outside as much as possible.

  The electronic device is not limited to the portable computer shown in the above embodiment, and can be implemented for other electronic devices such as a mobile phone. Moreover, in each said embodiment, although the spacer 27 is interposed with respect to the boss | hub part 31 provided in the vicinity of the operation part and the palm rest part, it is not limited to this. On the second case 22, the spacer 27 can be interposed at any location where the user touches. In each of the above embodiments, the case forming the lower half of the housing 20 is referred to as the first case 21, and the case forming the upper half of the housing 20 is referred to as the second case 22. However, the present invention is not limited to this. The present invention may be applied with the case forming the upper half of the housing 20 as the first case and the case forming the lower half of the housing 20 as the second case. In addition, the electronic device can be variously modified and implemented without departing from the gist of the invention.

DESCRIPTION OF SYMBOLS 11 ... Portable computer, 21 ... 1st case, 22 ... 2nd case, 23 ... Printed circuit board, 26 ... Screw, 27 ... Spacer, 31 ... Boss part, 35 ... Palm rest part, 37 ... Engagement part, 38 ... Hanging part, 41 ... Spacer main body, 41A ... Inner peripheral surface, 41B ... Both end faces, 41C ... Outer peripheral surface, 42 ... Ground layer, 43 ... Cap part, 47 ... Slit, 47A ... Back part, 48 ... Rib

Claims (10)

A metal first case;
A second case provided independently of the first case;
A boss portion that protrudes integrally from the first case toward the second case and is located in the vicinity of the heat-generating component,
A printed circuit board sandwiched between the boss portion and the second case and mounted with the heat-generating component;
A fixing member fixed to the boss portion so as to penetrate the second case and the printed circuit board and fix the second case to the first case;
A resin spacer provided at a position between the printed circuit board and the boss portion;
An electronic apparatus comprising: The spacer is
A cylindrical spacer body;
A conductive ground layer that is provided on a surface of the spacer body and electrically connects the first case and the printed circuit board;
The electronic apparatus according to claim 1, further comprising:   The electronic device according to claim 2, wherein the ground layer is provided across at least one of an inner peripheral surface and an outer peripheral surface of the spacer body and both end faces of the spacer body.   The electronic device according to claim 3, wherein the spacer has a cap portion, and the cap portion extends from the spacer main body so as to cover a tip end of the boss portion.   The electronic device according to claim 4, wherein the spacer has an engaging portion, and the engaging portion is caught by a hook portion provided in the boss portion.   The electronic device according to claim 5, wherein the engaging portion forms a part of the cap portion. A slit provided in one of the cap part and the boss part;
A rib that is provided on the other side of the cap part and the boss part and fitted inside the slit;
The electronic device according to claim 4, further comprising:   The electronic device according to claim 7, wherein a width of the slit becomes wider as it goes to an end portion on the opposite side to the back of the slit. An operation part is attached to the second case, and the second case has a palm rest part provided in front of the operation part,
The electronic device according to claim 6, wherein the boss portion is provided in the vicinity of at least one of the operation portion and the palm rest portion.   The electronic device according to claim 9, wherein the ground layer is a metal layer formed by plating the spacer body.

Images