JP3050723U - Heat sink with fixings - Google Patents

Abstract

(57) Abstract: A semiconductor element mounted on a substrate is mounted on a heat sink without any inconvenience without forming a cutout in a semiconductor element mounting plate of the heat sink. SOLUTION: Semiconductor element mounting plate 1 forming a heat radiating part
And a projecting portion 3 protruding outward from an arbitrary position of the semiconductor element mounting plate 1. Further, a fixing tool 5 is screwed to the semiconductor element mounting plate surface below the projecting portion 3 with a screw 4. This is a heat sink that presses the semiconductor element 6 by being attached thereto. A screw hole 30 is screwed at an arbitrary position of the overhang portion 3, and a bent metal plate is used as the fixing tool 5, one of which is formed so as to enter inside, and A screw hole is screwed at an arbitrary position, the bent part of the fixing tool 5 is directed outward, and the screw hole of one of the parts and the screw hole 30 of the overhanging part are opposed to each other, and By tightening with a screw through a screw hole, the other piece of the fixture 5 and the semiconductor element mounting plate 1 are pressed against each other while holding the semiconductor element 6 therebetween.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a heat sink for cooling a semiconductor element, the heat sink including a fixture for fixing the semiconductor element.

[0002]

[Prior art]

 The performance of semiconductor devices such as transistors and thyristors declines significantly when the temperature rises during use, and in severe cases the system may run away, so it is mounted on a board while being fixed to a heat sink with a heat radiating part .

When a semiconductor element is mounted on a substrate, a method of fixing the semiconductor element to a heat sink and then fixing its legs to the substrate, and a method of fixing the semiconductor element to the substrate in advance and then mounting the semiconductor element in the fixed state. There is a method of fixing to a heat sink. The latter method is used when it is difficult to attach the semiconductor element to the heat sink first, such as when the number of semiconductor legs or the forming process is applied.

In the latter method, that is, a method in which a semiconductor element is fixed to a substrate in advance, as shown in FIGS. 5 and 6 (Japanese Patent Publication No. 62-28768), the semiconductor element of the heat sink is attached to a heat sink. There has been a method in which a leaf spring member 8 is horizontally fastened to a mounting plate (heat radiating plate) 7 so that the semiconductor element 6 is crimped to the wall. However, in such mounting, since the screws 4 of the leaf spring 8 are tightened in the horizontal direction, that is, in the horizontal direction, it is difficult to tighten the screws in relation to other components mounted on the substrate 9, and the work is complicated. There was a problem.

For this reason, the heat sink shown in FIG. 7 (Japanese Utility Model Publication No. 4-402282), FIG. 8 (Japanese Utility Model Publication No. 4-14936), and FIG. 9 (Utility Model Registration No. 2506808) has been proposed. Basically, in each of these, an overhang 10 is provided from the semiconductor element mounting plate 7 of the heat sink, a fixing tool 11 is tightened from the overhang 10 via a screw 4, and the semiconductor element 6 is fixed by the fixing tool 11. It is fixed to the semiconductor element mounting plate 7. According to these, the attachment of the semiconductor element 6 to the heat sink is more difficult than the structure shown in FIGS. 5 and 6 in which the screws 4 are tightened in the vertical direction, that is, from the top, so that the screws are tightened from the lateral direction. Is eliminated.

[0006]

[Problems to be solved by the invention]

 However, in each of the structures shown in FIGS. 7 to 9, the end of the fixture 11 is inserted into the notch 12 formed in the semiconductor element mounting plate 7 of the heat sink, and the fixture 11 is inserted into the overhang 10 in that state. It was fastened with screw 4. That is, in those structures, it was necessary to form the notch 12 for insertion at the end of the fixture 11 in the semiconductor element mounting plate 7 of the heat sink. For this reason, the process of forming the notch 12 in the manufacturing process of the heat sink is complicated, and the cost is increased due to the increase in the number of manufacturing processes.

The present invention has been made in view of the above-mentioned problems of the prior art, and mounts a semiconductor element already mounted on a substrate without forming a cutout in a semiconductor element mounting plate of a heat sink. The purpose of the present invention is to provide a heat sink without any inconvenience in operation.

[0008]

[Means for Solving the Problems]

 In the structure shown in FIGS. 7 to 9 in which screws are tightened from above, the notch 12 is formed in the semiconductor element mounting plate 7 because the end of the fixture 11 is inserted therethrough. The main purpose is to fix to the heat sink. In FIG. 7, the fixing tool 11 is attached to the opposite side of the overhang 10, and in FIG. 8, the end of the fixing tool 11 inserted through the notch 12 is used as a fulcrum. In order to press the semiconductor element 6 with the force of the leverage and to use the force acting in the direction opposite to the direction of pressing one end of the fixing tool 11 in FIG. 9, the notch 12 is essential in each case. .

Here, considering only the structure shown in FIGS. 8 and 9 (that is, a structure in which the fixing tool 11 is fixed to the projecting portion 10 side), both are fastened to the projecting portion 10 of the fixing tool 11. The direction of the force applied is downward in both figures, and the shape of the fixture 11 is based on the use of the downward force, so the notch 12 is essential. I can say. In other words, if the shape of the fixture 11 is improved, a structure in which the notch 12 becomes unnecessary can be considered.

The inventors of the present invention have studied the structure of the fixture that does not require the notch, and as a result, have determined that the direction of the force to be fastened to the projecting portion of the fixture is directed upward, and at the same time, the semiconductor element is removed. Invented the shape of the fixture that can be pressed against the semiconductor mounting plate, and found that if such a force acts, the fixture can be tightened and the semiconductor element can be attached even if notches are not necessary, and the present invention was devised. That is what led to it.

[0011] For this reason, the heat sink provided with the fixing device according to the present invention includes a semiconductor element mounting plate forming a heat radiating portion, and a projecting portion projecting outward from an arbitrary position of the semiconductor element mounting plate. A heat sink that presses the semiconductor element into contact with the semiconductor element mounting plate surface below the overhanging portion by fastening a fixing tool with a screw, wherein a screw hole is screwed at an arbitrary position of the overhanging portion. At the same time, a bent metal plate is used as the fixing tool, one of which is formed so as to enter inward, and a screw hole is screwed at an arbitrary position to bend the bent metal plate. The other side of the fixture is tightened with screws through both screw holes with the screw portion facing outward and the screw hole of one of the portions facing the screw hole of the overhanging portion. Of the semiconductor element and the semiconductor element mounting plate Is characterized by being pressed while being held.

Here, the term “bent shape” refers to a shape in which a plate-shaped metal plate is bent at an acute angle of at least 90 ° or less at an arbitrary intermediate portion. The length of one divided part and the other divided part may or may not match. For example, the present invention includes shapes such as "ku" having a cross section of hiragana, "L" of alphabet, and "7" of numeral. Further, the mode in which one piece of the fixture enters into the inside is such that a gap is formed between the flat plate and the upper face of the one piece when the upper face of the one piece contacts the flat plate. It may be either a linear mode shown in FIG. 3 described later or a curved mode shown in FIG.

The mounting of the semiconductor element in the present invention is performed such that the bent portion of the fixture is directed outward, and the screw hole of the overhang portion of the heat sink and the screw hole of one side of the fixture are opposed to each other. At the same time, the semiconductor element is inserted between the semiconductor mounting plate of the heat sink and the other piece of the fixture, and screws are screwed from above the overhang in this state. Since one of the pieces is formed so as to enter into the inside, most of the upper surface of the piece does not contact the lower surface of the overhang, that is, between the piece and the overhang. A gap is formed in the area. As the screws are tightened, an upward force is applied to one of the parts, causing the gap to distort and the other part to incline toward the semiconductor mounting plate (in other words, toward the inside), and between them. The semiconductor elements are pressed against each other. If the screw is tightened, the other piece of the fixture will tilt more toward the semiconductor element mounting portion, and firmly clamp the semiconductor element. In other words, the semiconductor element can be mounted without forming a notch in the heat sink, and the screws are tightened from above the overhang, which makes it difficult to mount the semiconductor element already mounted on the board to the heat sink. There is no.

[0014]

[Embodiment of the invention]

 An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a heat sink according to a first embodiment, FIG. 2 shows a heat sink according to a second embodiment, and FIG. 3 shows a fixing device used for the heat sink shown in FIGS.

As shown in FIG. 1, the heat sink according to the first embodiment has a shape in which a plurality of fins 2 are formed on the ventral side of a vertical plate 1 serving as a semiconductor mounting plate. From this position, a projecting portion 3 having a convex portion whose tip is directed downward is formed. A screw hole 30 is formed in the overhang portion 3, and a fixing tool 5 is fastened by a screw 4 below the screw hole 30. The details of the fixture 5 will be described later.

In the heat sink of the second embodiment, as shown in FIG. 2, vertical plates 1 serving as semiconductor mounting plates are formed on both sides of a plurality of fins 2, respectively, as in the first embodiment. An overhang 3 similar to that of the above-described embodiment is formed from an arbitrary position on each of the back sides, and a screw hole 30 is formed in the overhang 3, and a fixing tool 5 is screwed below the overhang 3 with a screw 4. Be worn.

As shown in FIG. 3, the fixing tool 5 is bent at an arbitrary acute angle so that one piece 50 is shorter than the other piece 51, and the one piece 50 is further bent. The end is bent outward, and one of the pieces 50 is shaped to enter inward. Further, a screw hole 52 is screwed into the piece part 50. The other piece 51 has an arc shape with its end side extending outward, and presses the semiconductor element 6 at that portion. The manner in which the piece 50 of the fixture 5 enters the inside may be not only a straight form as shown in FIG. 3, but also a curved form as shown in FIG.

Next, a method of attaching the semiconductor element 6 in both embodiments will be described. The bent portion of the fixture 5 is directed outward, and the screw hole 30 of the heat sink extension 3 and the screw hole 52 of the piece 50 of the fixture 5 are arranged so as to face each other. The semiconductor element 6 is inserted between the semiconductor device 6 and the other piece 51 of the fixture 5, and in this state, the screw 4 is screwed from above the projecting portion 3. Since the piece 50 is formed in such a shape as to enter inside, the upper surface of the piece 50 does not contact the lower surface of the overhang portion 3 except for the end portion, that is, the piece 50 is A gap is formed between the protruding portion 3 (the state shown in FIG. 2A). When the screw 4 is tightened, an upward force is applied to the one part 50, and the gap is distorted, and the other part 51 tilts toward the semiconductor mounting plate side (in other words, the inside). A certain semiconductor element 6 is pressed into contact (the state shown in FIGS. 1 and 2B). If the screw 4 is tightened tightly, the one part 51 of the fixture 5 tilts more toward the vertical plate 1 side, and the semiconductor element 6 is firmly held.

[0019]

[Effect of the invention]

 As described above, according to the heat sink according to the present invention, the semiconductor element can be attached without forming a notch in the heat sink, so that the manufacturing process is simplified and the cost can be reduced. Further, since the screws are tightened from above the overhang, there is no trouble at all when attaching the semiconductor element already attached to the substrate to the heat sink.

[Brief description of the drawings]

FIG. 1 is a side view showing a first embodiment of the present invention.

FIG. 2 is a side view showing a second embodiment of the present invention;
(a) is a state diagram before a semiconductor element is attached, and (b) is a state diagram where a semiconductor element is attached.

FIG. 3 shows a fixture used in FIGS. 1 and 2, and (a)
Is a side view, and (b) is a perspective view.

FIG. 4 is a side view showing another embodiment of the fixture.

FIG. 5 is a heat sink provided with a conventional fixing device,
It is explanatory drawing of the structure which performs a screw fastening in a horizontal direction.

FIG. 6 shows a heat sink provided with a conventional fixing device.
FIG. 2 is an explanatory diagram of another configuration for performing screw tightening in a horizontal direction.

FIG. 7 shows a conventional heat sink provided with a fixing device
-40282), and is an explanatory diagram of a configuration in which screw fastening is performed in a vertical direction.

FIG. 8 is a view showing a conventional heat sink provided with a fixing device.
FIG. 14-14 is an explanatory diagram of another configuration for performing screw tightening in the vertical direction. (a) is a schematic perspective view, (b) is a side sectional view.

FIG. 9 is an explanatory diagram of another configuration of a heat sink provided with a conventional fixing device (utility model registration No. 2506808), in which screw fastening is performed in a vertical direction. (a) is a schematic perspective view,
(b) is a side sectional view, and (c) is an enlarged view of a notched portion.

[Explanation of symbols]

 1 Vertical plate 2 Fin 3 Overhang 4 Screw 5 Fixture 6 Semiconductor element

Claims (1)

[Utility model registration claims] A semiconductor element mounting plate forming a heat radiating portion;
A projecting portion that protrudes outward from an arbitrary position of the semiconductor element mounting plate, and further fixes the semiconductor element to the semiconductor element mounting plate surface below the projecting portion with a screw. A heat sink to be pressed against, wherein a screw hole is screwed at an arbitrary position of the overhang portion, and a bent metal plate is used as the fixing tool, and one of the pieces is formed so as to enter inside. A screw hole is screwed at an arbitrary position thereof, the bent portion of the fixing device is directed outward, and the screw hole of one of the parts and the screw hole of the overhanging portion are opposed to each other. A heat sink provided with a fixture, wherein the semiconductor element is pressed and held between the other piece of the fixture and the semiconductor element mounting plate by being tightened with a screw through a screw hole.