ELECTRONIC CONTROL DEVICE

Abstract

An upper lid forming an upper portion of a casing is formed by a metal (an aluminum alloy or the like) having a high heat radiation performance. The upper lid serves as a heat sink (a heat radiation member) radiating heat generated from electronic components within the casing to an external portion. A plurality of flat plate-shaped heat radiation fins are provided in an upper surface of the heat sink. A groove forming each of the heat radiation fins is open in a side surface of the heat sink without forming a step.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:

FIG. 1 is a perspective view of an electronic control device;

FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1;

FIG. 3 is an exploded perspective view of the electronic control device;

FIG. 4 is a perspective view of the electronic control device in a state of being mounted on a vehicle;

FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 4;

FIG. 6 is a perspective view of a heat sink in accordance with a modified embodiment;

FIG. 7 is a cross-sectional view of the heat sink taken along line 7-7 in FIG. 6; and

FIG. 8 is a perspective view of a prior art heat sink.

Claims

1. An electronic control device having an electronic circuit substrate, the electronic control device comprising: a casing accommodating said electronic circuit substrate;a metal heat sink provided in an upper portion of said casing and having a plurality of heat radiation fins; anda plurality of grooves formed in an upper portion of the casing, the grooves defining the fins, wherein each of said grooves extends to a peripheral edge of said heat sink so as to open to a side surface of said heat sink without forming a step.

2. The electronic control device according to claim 1, wherein a bottom surface of each of said grooves is sloped toward a peripheral edge of said heat sink.

3. The electronic control device according to claim 1, wherein a bottom surface of each of said grooves is sloped toward both ends from the center thereof.

4. The electronic control device according to claim 3, wherein a vertical cross sectional shape of each of said groove is formed in an inverted V.

5. The electronic control device according to claim 1, wherein said grooves are orthogonal to a side surface of said heat sink.

6. The electronic control device according to claim 1, wherein said grooves are provided in a radial pattern from the center of said heat sink.

7. The electronic control device according to claim 1, wherein said casing is provided with an upper lid, a casing main body, and a bottom lid, said heat sink being formed by said upper lid, said casing main body being provided with an insertion hole for inserting a screw, wherein a threaded hole is provided at a position corresponding to said insertion hole on an inner side surface of said upper lid, and wherein said heat sink is fixed to said casing main body by fastening the screw inserted into the insertion hole of said casing main body to the threaded hole of said upper lid.

8. The electronic control device according to claim 7, wherein a joint portion between said casing main body and said upper lid, and a joint portion between said casing main body and said bottom lid are sealed in a liquid tight manner by a sealing material.

9. The electronic control device according to claim 8, wherein said sealing material is formed by a silicone adhesive agent.