JP5496785B2 - Element mounting structure - Google Patents

Description

  The present invention relates to an element mounting structure.

  Patent Document 1 discloses a structure for attaching an element to a heat sink. In this type of mounting structure, a through hole is usually formed in the element, and a screw hole is formed in the heat sink. Then, when attaching the element, the screw is screwed from the through hole to the screw hole in a state where the through hole and the screw hole are aligned with each other. Then, the element is sandwiched between the head of the screw and the heat sink, so that the element is fixed to the heat sink.

  In the above case, a positioning structure for positioning the element on the heat sink may be provided so that a positional shift does not occur between the element and another electronic component connected to the element. Further, a rotation preventing structure for restricting the rotation of the element may be provided in the heat sink so that the element is not rotated along with the screw tightening.

JP 2007-324224 A

  By the way, when the positioning structure or the like is not provided on the heat sink and the alignment of the through hole and the screw hole is not properly performed, the tip of the screw scrapes the opening edge of the screw hole, etc. Etc. may occur. In addition, when the heat sink is provided with a positioning structure or the like, there is a situation that the configuration of the molding die for the heat sink becomes complicated and the cost is increased. In addition, there is a problem that processing for opening a screw hole in the heat sink is required, and that sufficient cleaning is required to remove foreign matters such as chips generated by the processing.

  The present invention has been completed based on the above circumstances, and an object of the present invention is to provide a fixing means other than screwing when mounting an element.

As means for achieving the above object, the invention of claim 1 is a mounting structure for mounting an element having an element body as a heat source and a resin outer shell covering the element body to a heat sink. The element is formed with bottomless recesses that are open on both the front and back surfaces of the outer shell, and the heat sink is inserted into the recess and is a protrusion for fixing the element to the heat sink. A thermoplastic resin member is inserted between the convex portion and the concave portion in the inserted state, and the resin member is melted and solidified by heating in a state of covering the convex portion. As a result, a closed portion that is in close contact with the outer peripheral surface on the tip side of the convex portion and the inner peripheral surface on the opening side of the concave portion is formed, and a flange portion that is in close contact with the opening edge of the concave portion is formed. Has characteristics.

The invention of claim 2 has the one described in claim 1, the root portion of the convex portion, the characterized in that the positioning surface inclined along the direction of insertion into the recess is formed.

The invention according to claim 3 is the one according to claim 1 or 2 , wherein the recess, the resin member, and the protrusion have a cross-sectional shape other than a circle capable of restricting the rotation of the protrusion in the recess. It has features where it has it.

According to a fourth aspect of the present invention, in the device according to any one of the first to third aspects, the outer shell portion of the element is formed of a material having a larger elastic coefficient than the resin member. It has the characteristics.

<Invention of Claim 1>
Since there is a space for inserting the thermoplastic resin member between the convex portion and the concave portion in the inserted state, it is necessary to precisely align the concave portion and the convex portion when inserting the convex portion into the concave portion. There is no. In addition, the resin member is melted and solidified by heating, so that a closed portion is formed in close contact with the outer peripheral surface on the tip end side of the convex portion and the inner peripheral surface on the opening side of the concave portion, and is in close contact with the opening edge of the concave portion. Since the flange portion to be formed is formed, the fastening property between the concave portion and the convex portion is improved, and the element is tightly fixed to the heat sink. In addition, the hook portion reliably prevents the element from being detached from the heat sink. Therefore, a fixing means other than screwing is provided for mounting the element.

Also, since the convex part is formed on the heat sink and the concave part is formed on the element, unlike the case where the concave part is formed on the heat sink, the heat dissipation volume of the heat sink does not decrease and the heat dissipation of the heat sink is good. Demonstrated.

<Invention of Claim 2 >
Since the positioning slope which inclines along the direction of insertion into the recess is formed at the base of the projection, the projection can be automatically positioned with respect to the recess at the final stage of the insertion of the projection into the recess. it can.

<Invention of Claim 3 >
Since the concave portion, the resin member, and the convex portion have a cross-sectional shape other than a circle that can restrict the rotation of the convex portion in the concave portion, the element is prevented from rotating carelessly with respect to the heat sink.

<Invention of Claim 4 >
Since the outer shell portion of the element is formed of a material having a larger elastic coefficient than the resin member, the element is prevented from being damaged when an impact or the like is applied.

It is a top view of the attachment structure of the element which concerns on Embodiment 1 of this invention. It is AA sectional drawing of FIG. It is principal part sectional drawing before attaching a resin member to a convex part. It is principal part sectional drawing immediately after attaching the resin member to a convex part. 6 is a plan view of an element mounting structure according to Embodiment 2. FIG.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. The first embodiment includes an element 10, a heat sink 30 to which the element 10 is attached, and a resin member 60 that is mounted between the element 10 and the heat sink 30.

  The element 10 includes an element main body (not shown) as a heat source and a resin outer shell portion 11 covering the periphery of the element main body. The outer shell portion 11 has, for example, a rectangular plate shape, and a flat flat surface 12 is formed on the back surface (bottom surface) thereof.

  On the back surface of the outer shell portion 11, a recess 13 is formed to be open. The concave portion 13 is configured as a bottomless circular hole that also opens on the surface of the outer shell portion 11.

  The heat sink 30 is made of metal such as aluminum, and is made of, for example, aluminum die casting. A flat flat surface 31 is formed on the surface of the heat sink 30. When the element 10 is attached, heat from the element body is transferred to the heat sink 30 via both flat surfaces 12 and 31 of the element 10 and the heat sink 30.

  Further, a convex portion 32 is formed on the surface of the heat sink 30 corresponding to the mounting position of the element 10. The convex portion 32 has a substantially cylindrical shape that rises in a direction orthogonal to the surface of the heat sink 30. Specifically, as shown in FIG. 3, the convex portion 32 includes a large-diameter portion 33 that gradually decreases in diameter as it gets away from the surface side of the heat sink 30, and an upper end (smallest diameter portion) of the large-diameter portion 33. A small-diameter portion 34 that rises with a substantially constant diameter toward the distal end side, and a guide portion 35 that gradually decreases the diameter dimension from the upper end to the distal end of the small-diameter portion 34. The outer peripheral surface of the large-diameter portion 33 is a tapered positioning slope 36 that gradually decreases in diameter toward the upper end thereof.

The outer diameter of the base of the large diameter portion 33 is 1.5 to 3 times the outer diameter of the small diameter portion 34, and is slightly smaller than the inner diameter of the recess 13. The space between the outer peripheral surface of the small diameter portion 34 and the inner peripheral surface of the concave portion 13 is an insertion space 80 for the resin member 60, and a larger clearance than between the outer peripheral surface of the large diameter portion 33 and the inner peripheral surface of the concave portion 13. Has been.
The total height of the large-diameter portion 33 is ½ to ３ of the total height of the convex portion 32, and the total height of the convex portion 32 is substantially the same as the total height of the concave portion 13, that is, the thickness of the outer shell portion 11. ing. Moreover, the guide part 35 makes insertion guidance to the recessed part 13 of the convex part 32, Comprising: The formation range is restricted to the very narrow range. A concave groove 39 is formed on the entire surface of the heat sink 30 around the root of the large diameter portion 33.

  The resin member 60 is formed of a thermoplastic resin selected from, for example, polyethylene, polyvinyl chloride, polypropylene, polystyrene, polybutadiene, polyvinylidene chloride, polymethyl methacrylate, polyethylene terephthalate, polyacetal, polyamide, or engineering plastic. Has been. The resin member 60 has a cap shape as a whole and has a recessed portion 61 that opens downward. The concave portion 61 can be fitted with the tip of the convex portion 32, and the inner diameter of the concave portion 61 is made smaller than the outer diameter of the small diameter portion 34. For this reason, the recessed part 61 of the resin member 60 is fastened to the tip part of the convex part 32 by press fitting.

  The top surface of the resin member 60 is configured as a pressure receiving surface 62 that is pressed and heated by the pressing die 90. After the convex portion 32 is inserted into the concave portion 13, the concave portion 61 is put on the tip portion of the convex portion 32, and the pressure receiving surface 62 is pressed and heated in this state, and the upper end portion of the resin member 60 is crushed. It is. As a result, as shown in FIG. 2, a blocking portion 64 is formed on the upper end portion of the resin member 60 so as to be in close contact with the outer peripheral surface on the distal end side of the convex portion 32 and the inner peripheral surface on the surface side (opening side) of the concave portion 13. At the same time, a flange 65 is formed that is in close contact with the opening edge on the surface side of the recess 13.

  A portion of the resin member 60 below the closing portion 64 is an open portion 66 having a gap with the inner peripheral surface of the recess 13. The blocking part 64 has a form that is thicker than the opening part 66. In addition, the flange portion 65 has a shape in which the diameter is expanded while being substantially orthogonal to the closing portion 64.

Next, a method for attaching the element 10 to the heat sink 30 will be described.
The element 10 is arranged on the surface side of the heat sink 30, and the element 10 is pulled down from the state. In the process of pulling down, the small diameter portion 34 is inserted into the recess 13, and then the large diameter portion 33 is inserted into the recess 13. At the beginning of insertion, the small-diameter portion 34 is loosely fitted in the concave portion 13, so that it is not necessary to strictly align the convex portion 32 and the concave portion 13. On the other hand, in the final stage of insertion, the relative position of the convex portion 32 in the concave portion 13 is appropriately corrected by the positioning slope 36, and the convex portion 32 is inserted into the concave portion 13 in the positioning state when the insertion is completed. When the concave portion 13 is normally inserted into the convex portion 32 in this way, both the flat surfaces 12 and 31 of the element 10 and the heat sink 30 are substantially in contact with each other as shown in FIG. In this case, interference between the base side of the convex portion 32 and the back surface side of the concave portion 13 is avoided by the concave groove 39, so that the contact state between the flat surfaces 12, 31 is ensured.

  Subsequently, as shown in FIG. 4, the resin member 60 is inserted into the insertion space 80, and the tip of the convex portion 32 is covered with the resin member 60. At this time, there is a gap between the outer peripheral surface of the resin member 60 and the inner peripheral surface of the recess 13, and sliding resistance is generated between the outer peripheral surface of the resin member 60 and the inner peripheral surface of the recess 13. Is suppressed.

  Next, the upper end portion of the resin member 60 is melted and solidified by pressing and pressing the pressing mold 90 against the pressure receiving surface 62 of the resin member 60, and as shown in FIG. 65 is formed. By forming the closing portion 64 and the flange portion 65 in this way, the convex portion 32 and the concave portion 13 are tightly fixed to each other via the resin member 60.

  As described above, according to the present embodiment, the insertion space 80 into which the thermoplastic resin member 60 is inserted is held between the convex portion 32 and the concave portion 13 in the inserted state. When inserting the convex part 32, it is not necessary to align the recessed part 13 and the convex part 32 exactly | strictly. Further, the resin member 60 is melted and solidified by heating, so that a closed portion 64 is formed in close contact with the outer peripheral surface on the distal end side of the convex portion 32 and the inner peripheral surface on the opening side of the concave portion 13. Since the flange portion 65 is formed in close contact with the opening edge, the fastening property between the concave portion 13 and the convex portion 32 is enhanced, and the element 10 is tightly fixed to the heat sink 30. Furthermore, the flange 65 reliably prevents the element 10 from being detached from the heat sink 30. Therefore, a fixing means other than screwing is provided for mounting the element 10.

  In addition, since the convex portion 32 is formed in the heat sink 30 and the concave portion 13 is formed in the element 10, unlike the case where the concave portion is formed in the heat sink 30, the heat dissipation volume of the heat sink 30 is not reduced. The heat dissipation of 30 is exhibited well.

  Moreover, since the positioning slope 36 which inclines along the insertion direction to the recessed part 13 is formed in the large diameter part 33 of the convex part 32, in the final stage of insertion of the convex part 32 to the recessed part 13, the convex with respect to the recessed part 13 is formed. Positioning of the part 32 can be performed automatically.

  Furthermore, according to the present embodiment, the outer shell portion 11 of the element 10 is formed of a material having a larger elastic coefficient than the resin member 60. This prevents the element 10 from being damaged when an impact or the like is applied.

<Embodiment 2>
FIG. 5 shows a second embodiment of the present invention. In the second embodiment, unlike the first embodiment, the concave portion 13A, the resin member 60A, and the convex portion 32A have a cross-sectional shape other than a circular shape.

  That is, the inner periphery of the recess 13A includes a pair of linear first opposing sides 18 that face each other, and a pair of arc-shaped second opposing sides 19 that are substantially orthogonal to both the first opposing sides 18 and face each other. It is divided by.

  The outer periphery of the closing portion 64 </ b> A of the resin member 60 </ b> A has a pair of linear third opposing sides 71 that are in close contact with the first opposing side 18 and a pair of circles that are in close contact with the second opposing side 19 when the element 10 is attached. It is partitioned by an arcuate fourth opposing side 72. Further, the inner periphery of the blocking portion 64 has a pair of linear fifth opposing sides 73 substantially parallel to the third opposing sides 71 and a pair of arc-shaped sixth opposing sides 74 substantially parallel to the fourth opposing sides 72. It is divided by and.

  The outer periphery of the convex portion 32 is a pair of linear seventh opposing sides 37 that are in close contact with the fifth opposing side 73 and a pair of arcuate shapes that are in close contact with the sixth opposing side 74 when the element 10 is attached. It is partitioned by an eighth opposing side 38. In short, all of the concave portion 13, the resin member 60, and the convex portion 32 have a bowl-shaped cross section and are arranged to be in close contact with each other.

  According to the second embodiment, since the concave portion 13, the resin member 60, and the convex portion 32 each have a cross-sectional shape other than a circle, the rotation of the resin member 60 and the convex portion 32 in the concave portion 13 is prevented. As a result, the element 10 is prevented from rotating carelessly with respect to the heat sink 30.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) The form which a convex part stands up with a substantially constant diameter over the whole height may be sufficient.
(2) In the first embodiment, the heat sink may be provided with a detent structure that restricts the element from rotating carelessly.
(3) In the second embodiment, the concave portion, the resin member, and the convex portion only have to have a cross-sectional shape other than a circle that can restrict the rotation of the convex portion in the concave portion, and the specific sectional shape thereof It is not intended to limit.

DESCRIPTION OF SYMBOLS 10 ... Element 13, 13A ... Concave part 30 ... Heat sink 32, 32A ... Convex part 36 ... Positioning slope 60, 60A ... Resin member 64, 64A ... Closure part 65 ... Claw part

Claims (4)

A mounting structure for mounting an element having an element body as a heat source and a resin outer shell covering the element body to a heat sink,
The element is formed with a bottomless recess that opens on both the front and back surfaces of the outer shell,
The heat sink is inserted into the concave portion, and a convex portion for fixing the element to the heat sink is formed.
A thermoplastic resin member is inserted between the convex portion and the concave portion in the inserted state,
The resin member is covered with the convex portion and is melted and solidified by heating so that the closed portion is in close contact with the outer peripheral surface on the distal end side of the convex portion and the inner peripheral surface on the opening side of the concave portion. And an eaves part closely contacting the opening edge of the recess. The element mounting structure according to claim 1 , wherein a positioning inclined surface that is inclined along an insertion direction into the concave portion is formed at a base portion of the convex portion . The element mounting structure according to claim 1 , wherein the concave portion, the resin member, and the convex portion have a cross-sectional shape other than a circle capable of restricting rotation of the convex portion in the concave portion . The element mounting structure according to any one of claims 1 to 3 , wherein the outer shell portion of the element is formed of a material having a larger elastic coefficient than the resin member.

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