JP5348331B2 - Printed circuit board support member, printed circuit board unit, and electronic device - Google Patents

Description

  The present invention relates to a printed circuit board support member, a printed circuit board unit, and an electronic device.

  A technique for cooling a heat generating component of a printed circuit board employed in an electronic device is known. For example, in order to cool the heat generating component, it is conceivable to provide a heat sink that contacts the heat generating component. The heat sink is held by the holding member and is disposed on the surface side of the printed board on which the heat generating component is provided. In addition, a support member that supports the printed circuit board is disposed on the side of the printed circuit board on which the heat generating components are not provided. The support member is coupled to the holding member, and is assembled so that the printed board is sandwiched between the support member and the holding member. Patent Documents 1 and 2 disclose techniques for attaching components to a substrate.

Japanese Patent No. 2666912 JP 2003-7380 A

  It is conceivable to provide a protrusion on such a support member and to provide a positioning hole on the mounting plate. If the protrusion is not properly fitted in the hole, the support member may not follow the attachment plate and may be inclined with respect to the attachment plate. In this case, there is a possibility that the printed board is attached to the attachment plate in a state where the support member is deviated from a desired posture. If the printed circuit board is attached to the mounting plate in such a state, the printed circuit board may be supported in a bent state.

  An object of the present invention is to provide a printed circuit board support member that suppresses bending of the printed circuit board, a printed circuit board unit including the printed circuit board unit, and an electronic device including the printed circuit board unit.

  The printed circuit board support member disclosed in the present specification is sandwiched between a back surface of a printed circuit board on which a heat generating component is mounted and a mounting plate to which the printed circuit board can be attached, and supports the back surface. A connecting portion connectable to a holding member that holds a heat sink that receives heat from the heat-generating component, a protrusion that fits into a positioning hole of the mounting plate and positions the support portion, and the protrusion And the elastic portion is elastically deformable, and the elastic portion is elastically deformed by pressing the support portion against the mounting plate in a state where the protrusion and the hole are not fitted. The support portion follows the mounting plate.

  A printed circuit board unit disclosed in this specification includes the above-described printed circuit board support member, the heat sink, the holding member, and the printed circuit board.

  An electronic device disclosed in this specification includes the printed circuit board unit and the mounting plate.

  It is possible to provide a printed circuit board support member that suppresses bending of the printed circuit board, a printed circuit board unit including the printed circuit board unit, and an electronic device including the printed circuit board unit.

FIG. 1 is an explanatory diagram of an electronic apparatus according to the present embodiment. FIG. 2 is an exploded perspective view of the printed circuit board unit. FIG. 3 is an explanatory view of a support member. FIG. 4 is an explanatory diagram of the support member. FIG. 5 is an explanatory diagram of the support member. FIG. 6 is an explanatory diagram of a state in which the printed circuit board unit is assembled to the mounting plate. FIG. 7 is an explanatory diagram of a state in which the printed circuit board unit is assembled to the mounting plate. 8A to 8C are explanatory diagrams when the printed circuit board unit is assembled to the mounting plate in a state where the support member is not properly positioned on the mounting plate. FIG. 9 is an explanatory diagram of the ease of fitting the protrusion into the hole. FIG. 10 is an enlarged view of a cross section of the protrusion.

  FIG. 1 is an explanatory diagram of an electronic apparatus 1 according to the present embodiment. The electronic device 1 is a personal computer. The electronic device 1 includes a main body housing 2 and a support base 4 that supports the main body housing 2. The main body housing 2 is provided with a display 3 capable of displaying an image. Hardware for realizing a function as a personal computer is built in the main body housing 2.

  FIG. 2 is an exploded perspective view of the printed circuit board unit U. FIG. A printed circuit board unit U is accommodated in the main body housing 2. The printed circuit board unit U includes a printed circuit board 10, a holding member 40 assembled to the printed circuit board 10, and a support member 50. The printed circuit board 10 is a printed circuit board 10 on which electronic components for controlling the operation of the entire electronic device 1 are mounted. The printed circuit board 10 functions as a mother board. The printed circuit board 10 has a first surface 11 and a second surface 12, and a heat generating component 15 is mounted on the first surface 11. The second surface 12 is not shown in FIG. 2, but is shown in FIG. The heat generating component 15 is an electronic component that generates heat when power is supplied. The heat generating component 15 is, for example, a CPU, but is not limited thereto, and may be, for example, a graphic chip. A memory M is mounted on the first surface 11 of the printed circuit board 10.

  The heat sink 30 is made of a metal having good thermal conductivity such as copper or aluminum alloy. The heat sink 30 is held by a holding member 40. The holding member 40 is a metal thin plate shape. The holding member 40 holds a fan (not shown) that is cooled by blowing the heat sink 30. The holding member 40 has a hole for allowing air to pass to the fan.

  The mounting plate 90 is accommodated in the main body housing 2. The mounting plate 90 is made of metal. The mounting plate 90 is provided with a plurality of support pins 94 for supporting the printed circuit board 10. A support member 50 is disposed between the printed board 10 and the mounting plate 90. The support member 50 is coupled to the holding member 40 so as to sandwich the printed circuit board 10. The attachment plate 90 is provided with two holes 96 for positioning the support member 50.

  3, 4, and 5 are explanatory views of the support member 50. FIG. 5 is a cross-sectional view of the support member 50. The support member 50 is made of synthetic resin. The support member 50 is formed in a support part 51, three connecting holes 52 provided in the support part 51, a plate-like part 54 continuous to the support part 51, an elastic part 55 formed in the plate-like part 54, and an elastic part 55. Projecting portion 56. The support surface 51 s of the support portion 51 abuts on and supports the second surface 12 of the printed circuit board 10. The protrusion 56 protrudes toward the mounting plate 90. The support member 50 is positioned with respect to the mounting plate 90 by fitting the protrusions 56 into the holes 96 of the mounting plate 90. The elastic portion 55 is determined by the cutout portion C. The elastic part 55 is elastically deformable. The support portion 51 is provided with an opening OP. The support portion 51 includes a frame-shaped portion and three extending portions extending outward from the frame-shaped portion. In addition, the shape of the support part 51 is not limited to such a shape.

  6 and 7 are explanatory views showing a state in which the printed circuit board unit U is assembled to the mounting plate 90. FIG. In FIG. 6, a part is notched. The holding member 40 and the supporting member 50 are assembled to the printed circuit board 10 so as to sandwich the printed circuit board 10 by screws S that are fitted in the screw holes 42 of the holding member 40 and the connection holes 52 of the supporting member 50 in common. The screw S is not shown in FIGS. 6 and 7, but is shown in FIG. The holding member 40 to which the heat sink 30 is previously attached may be assembled to the printed circuit board 10 by the support member 50, or the holding member 40 to which the heat sink 30 is not attached is assembled to the printed circuit board 10 by the support member 50. After attaching, the heat sink 30 may be attached to the holding member 40.

  Thus, the connection hole 52 of the support member 50 functions as a connection portion that can be connected to the holding member 40. A thread groove is formed inside the connection hole 52. Next, the protrusion 56 of the support member 50 is fitted into the hole 96 of the attachment plate 90, and the support pin 94 of the attachment plate 90 and the printed board 10 are fixed with screws. As a result, the printed board 10, the holding member 40, and the support member 50 are assembled to the mounting plate 90. A heat receiving plate P is disposed on the lower surface of the heat sink 30. Heat of the heat generating component 15 is transmitted to the heat sink 30 through the heat receiving plate P. The heat receiving plate P is made of a metal having good thermal conductivity.

  Next, the support member 50 will be described in detail. A case where the printed board unit U is assembled to the mounting plate 90 in a state where the support member 50 is not properly positioned on the mounting plate 90 will be described. 8A to 8C are explanatory views when the printed circuit board unit U is assembled to the mounting plate 90 in a state where the support member 50 is not properly positioned on the mounting plate 90. In FIGS. 8A to 8C, 20 is omitted. Although details will be described later, FIGS. 8A to 8C are based on the assumption that the protrusion 56 is not fitted into the hole 96, and the printed circuit board unit U is always attached to the mounting plate 90 in such a state. It cannot be assembled.

  As shown in FIG. 8A, it is assumed that the support member 50 is disposed on the mounting plate 90 in a state where one of the two protrusions 56 is not fitted in the hole 96. In this state, the support surface 51 s of the support portion 51 is inclined with respect to the attachment plate 90 with respect to the attachment plate 90, and the support member 50 is shifted from a desired posture. When the support member 50 is pressed against the mounting plate 90 in this state, as shown in FIGS. 8B and 8C, the elastic portion 55 provided with the projection 56 not fitted in the hole 96 is elastically deformed so as to bend. To do. Accordingly, the support member 50 follows the mounting plate 90, and the support member 50 assumes a desired posture. In this state, the printed circuit board 10 is appropriately supported by the support member 50 by connecting the support pins 94 and the printed circuit board 10.

  For example, when the elastic part 55 is not elastically deformable, when the printed board 10 is fixed to the support pins 94 from the state of FIG. 8A, the printed board 10 is assembled to the mounting plate 90 while the support member 50 is tilted. Become. For this reason, since the printed circuit board 10 is supported by the inclined support member 50, the printed circuit board 10 bends. As a result, the printed circuit board 10 may be damaged. Further, the support member may be damaged.

  However, in this embodiment, even when the protrusion 56 is not fitted in the hole 96, the support member 50 follows the mounting plate 90 due to the elastic deformation of the elastic portion 55. Thereby, the support member 50 can support the printed circuit board 10 in a desired posture, and can suppress the bending and breakage of the printed circuit board 10. Therefore, when the printed circuit board unit U is assembled to the mounting plate 90, the support member 50 does not necessarily have to be properly positioned with respect to the mounting plate 90. Therefore, the workability of assembling the printed circuit board unit U to the mounting plate 90 is improved.

  Further, when considering the variation in position among the printed circuit board 10, the holding member 40, and the support member 50, when the printed circuit board unit U is assembled to the mounting plate 90, the protrusion 56 fits into the hole 96 appropriately. There are cases where it is impossible. Even in such a case, the printed circuit board unit U can be assembled to the mounting plate 90 while suppressing the printed circuit board 10 from being bent.

  Further, since the elastic portion 55 is elastically deformed, it is possible to prevent the elastic portion 55 from being damaged when the printed board unit U is assembled to the mounting plate 90 in a state where the support member 50 is not positioned on the mounting plate 90.

  Further, the support member 50 and the mounting plate 90 are not directly fixed, and the support member 50 is only pressed against the mounting plate 90 by fixing the printed circuit board 10 to the mounting plate 90 to the last. It is. That is, the support member 50 is assembled to the printed circuit board 10. Therefore, in a state where the printed circuit board unit U is assembled to the mounting plate 90, the printed circuit board 10, the holding member 40, and the support member 50 can be separated from the mounting plate 90 as a unit. For this reason, the printed circuit board unit U can be employed as a maintenance part. For example, a printed circuit board unit U in which the printed circuit board 10, the holding member 40, and the support member 50 are integrated can be adopted as a maintenance part for replacement when the electronic apparatus 1 fails. For example, when the support member 50 is screwed or locked to the mounting plate 90, the printed circuit board 10, the holding member 40, the support member 50, and the mounting plate 90 are integrated. In such a case, the manufacturer needs to hold a unit in which the printed circuit board 10, the holding member 40, the support member 50, and the mounting plate 90 are integrated as a maintenance part. For this reason, the size of the maintenance part increases, and the manufacturing cost of the maintenance part also increases. However, in the present embodiment, since the printed circuit board 10, the holding member 40, and the support member 50 are integrated, the size of the maintenance part can be reduced, and the manufacturing cost of the maintenance part can be suppressed.

  Even if both of the two protrusions 56 are not fitted in the holes 96, the two elastic portions 55 are elastically deformed, and the support member 50 can follow the mounting plate 90.

  As shown in FIGS. 3 and 4, the elastic portion 55 has a cantilever shape extending from the support portion 51 along the mounting plate 90. For this reason, the elastic part 55 is easily elastically deformed. Further, the elastic portion 55 is formed by notching a plate-like portion 54 that is thinner than the thickness of the support portion 51 in the direction perpendicular to the mounting plate 90. This also facilitates elastic deformation of the elastic portion 55.

  Next, the ease of fitting the protrusion 56 into the hole 96 will be described. FIG. 9 is an explanatory diagram of the ease of fitting of the protrusion 56 into the hole 96, and FIG. 10 is an enlarged view of the cross section of the protrusion 56. The protrusion 56 has a substantially frustoconical shape whose diameter decreases toward the mounting plate 90. The protrusion 56 has an inclined surface 56s that defines a substantially frustoconical shape. The inclined surface 56s is inclined so as to approach the mounting plate 90 with respect to an axial center that passes through the center of the protrusion 56 and extends in the protruding direction in a sectional view.

  As shown in FIG. 9, when the printed circuit board unit U is assembled to the mounting plate 90, it is conceivable that the inclined surface 56 s of the protrusion 56 contacts the edge of the hole 96. When the printed circuit board unit U is assembled in such a state, the elastic portion 55 is elastically deformed. Accordingly, the protrusion 56 is pressed by the elastic restoring force of the elastic portion 55 so as to normally fit in the hole 96. In this way, even when the protrusion 56 is in contact with the edge of the hole 96, the protrusion 56 is easily fitted into the hole 96. Further, by providing the protrusion 56 with the inclined surface 56s, the degree of elastic deformation of the elastic portion 55 can be suppressed.

  The length A of the inclined surface 56 s in the direction parallel to the printed circuit board 10 is the length of the play between the holding member 40 and the support member 50 in the above direction and the direction of the play between the printed circuit board 10 and the mounting plate 90. Greater than the sum of the length of As a result, even when the protrusion 56 is not properly fitted in the hole 96, the inclined surface 56 s comes into contact with the edge of the hole 96 as shown in FIG. 9. Thereby, fitting of the protrusion 56 to the hole 96 can be promoted, and the amount of elastic deformation of the elastic portion 55 can be suppressed. The length A of the inclined surface 56s is the sum of the variation in the size of the support member 50, the variation in the size of the mounting plate 90, and the variation in the size of the printed circuit board 10 in addition to the above-described play. It may be larger than the length.

  The length B of the inclined surface 56 s in the direction perpendicular to the printed circuit board 10, in other words, the direction perpendicular to the mounting plate 90 is the elastic restoration of the elastic portion 55 when the inclined surface 56 s abuts the edge of the hole 96. The projection 56 may be set so as to be properly fitted in the hole 96 by force.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

  In this embodiment, a personal computer has been described as an example of an electronic device, but the present invention is not limited to this. The electronic device may be, for example, a portable device or a stationary device. Examples of portable devices include notebook computers, tablet computers, portable game machines, and stationary devices such as desktop computers, television devices, magnetic disk reproducing devices that can read and reproduce magnetic disks, audio devices, It may be.

  In this embodiment, the CPU is described as an example of the heat generating component. However, any component that generates heat when power is supplied may be used. For example, the heat generating component may be a graphic chip.

  In the above embodiment, the support member 50 is made of synthetic resin, but may be made of metal. In that case, an insulating sheet is attached to the surface of the support member 50 on the heat sink 30 side.

  In the above-described embodiment, the protrusion 56 may have a substantially hemispherical shape, a substantially conical shape, a substantially pyramid shape, or a substantially truncated pyramid shape.

DESCRIPTION OF SYMBOLS 1 Electronic device 10 Printed circuit board 15 Heat generating component 30 Heat sink 40 Holding member 50 Support member 51 Support part 51s Support surface 52 Connection hole 54 Plate-like part 55 Elastic part 56 Projection part 56s Inclined surface 90 Mounting plate 54 Plate-like part U Printed circuit board unit

Claims (7)

Sandwiched between the back surface of the surface of the printed circuit board on which the heat generating component is mounted and a mounting plate to which the printed circuit board can be attached, and a support portion that supports the back surface;
A connecting portion connectable to a holding member that holds a heat sink that receives heat from the heat-generating component;
A protrusion that is fitted into a positioning hole of the mounting plate and the support portion is positioned;
An elastic part provided with the protrusion and elastically deformable,
Supporting the printed circuit board in which the elastic portion is elastically deformed and the support portion follows the attachment plate when the support portion is pressed against the attachment plate in a state where the protrusion and the hole are not fitted. Element.   The printed circuit board support member according to claim 1, wherein the elastic portion has a cantilever shape extending from the support portion along the mounting plate.   The support member for a printed circuit board according to claim 1 or 2, wherein the elastic portion is formed by notching a plate-like portion that is thinner than a thickness of the support portion in a direction perpendicular to the mounting plate.   4. The printed circuit board support member according to claim 1, wherein the protrusion has an inclined surface that is inclined so that the diameter decreases toward the mounting plate. 5.   The length of the inclined surface in the direction parallel to the printed circuit board is the length of the play between the holding member and the support member in the direction and the play of the play between the printed circuit board and the mounting plate. The printed circuit board support member of claim 4, wherein the printed circuit board support member is larger than a total length. A printed circuit board support member according to any one of claims 1 to 5,
The heat sink;
The holding member;
A printed circuit board unit comprising the printed circuit board. A printed circuit board unit according to claim 6;
An electronic device comprising the mounting plate.

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