JPH09130073A - Electric device box for electronic circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the electric device box for an electronic circuit provided with a compact forced ventilation function having positive heat dissipating power by a method wherein a heat sink is provided inside a case. SOLUTION: An electronic circuit board and a power device are housed in an electric device box 1, and the heat radiating fin 3 of a heat sink is attached to the inner surface of the box. Also, a forced ventilating fan 2 is provided on the other surface of the electric device box 1. The electric device box 1 takes in ventilation air from the aperture part 4 of the electric device box 1 located on the front part of the heat radiating fin, the ventilating air passes the surface of the heat radiating fin 3 and exhausted from the forced ventilation fan 2. The aperture part 4 is provided on the upstream part of the flow of air in such a manner that the ventilation air is allowed to excellently flow over the surface of the heat radiating fin 3. As a result, the heat radiated from the board and the heat radiated from the power device can be discharged simultaneously by the common ventilation fan 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrical equipment box of an electronic circuit device such as an electronic control device that radiates heat by forced ventilation, and more particularly to a structure in which a heat sink is incorporated inside the electrical equipment box.

[0002]

2. Description of the Related Art Conventionally, a heat sink of a power element that cannot be placed on a substrate has a means for allowing the heat radiation fin portion of the heat sink to be exposed outside the electrical equipment box for natural heat dissipation or forcible heat dissipation by an external cooling fan. It has been taken so far. However, in this case, natural heat dissipation requires a large heat sink, which makes the electrical equipment box of electronic circuit devices such as electronic control devices very large. On the other hand, in the case of the external cooling fan, it is necessary to provide a separate means for mounting the fan, which makes the use of the electronic control device cumbersome.

[0003]

SUMMARY OF THE INVENTION In order to solve the problems in the prior art as described above, the present invention provides an electrical equipment box of an electronic circuit device having a forced ventilation function which has a compact and reliable heat dissipation capability.

[0004]

The invention according to claim 1 of the present application is an electrical equipment box having a forced ventilation fan and an electronic circuit board and a heat sink for heat dissipation of power elements. This is achieved by taking in the heat sink and the electronic circuit board in a common electric equipment box, and discharging the heat emitted from the power element and the components on the board by a forced ventilation fan.

The invention according to claim 2 of this application is an electric equipment box having a fan for forced ventilation, and a heat sink for radiating heat of an electronic circuit board and a power element. The heat radiating fin side of the heat sink is on the wall surface of the electric equipment box. This is achieved by providing the ventilation air intake port of the electrical equipment box on the surface of the heat radiation fin of the heat sink while mounting it as closely as possible.

[0006] The invention according to claim 3 of this application is an electric equipment box having a fan for forced ventilation, in which heat sinks for radiating electronic circuit boards and power elements are mounted along the wall surface as closely as possible An air intake port is provided on the front surface of the heat dissipation fin of the heat sink, and the size of the opening is set to 1/5 to 1/2 of the length of the heat sink in the same direction in the flow direction of the heat sink. This can be achieved by providing the heat sink in the direction perpendicular to the same length as or slightly smaller than that of the heat sink in the upstream portion of the air flow.

The invention according to claim 4 of the present application provides a ventilation in an electrical equipment box having a fan for forced ventilation, and a heat sink for heat dissipation of an electronic circuit board and a power element, which are mounted on the wall surface as closely as possible to each other. This is achieved by providing an air intake port on the side surface of the heat dissipation fin of the heat sink and making the size of the opening smaller than the approximate size of the side surface.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 are block diagrams of an electrical equipment box of an electronic circuit device having a heat dissipation capability and a forced ventilation function according to the present invention. In the figure, 1 is an electrical equipment box, 2 is a fan for forced ventilation, 3 is a radiation fin, and 4 is an opening.

In the embodiment of the present invention shown in FIG. 1, an electrical equipment box 1
The electronic circuit board and the power element are housed in the box, and the heat radiation fins 3 of the heat sink are attached to the inner surface of the box. A forced ventilation fan 2 is provided on the other surface of the electrical equipment box 1. The electrical equipment box 1 takes in ventilation air from the open portion 4 of the electrical equipment box 1 on the front surface of the heat radiation fin, flows through the surface of the heat radiation fin 3 and discharges air from the forced ventilation fan 2. At this time, the heat of the radiation fins 3 and the heat of the substrate (not shown) are simultaneously discharged.

The opening portion is provided at the upstream portion of the air flow so that the ventilation air flows well on the surface of the radiation fin. If the opening is too small, the work rate of the forced ventilation fan becomes poor, and at the same time, the flow noise of ventilation air becomes loud. Further, even if it is too large, a portion where ventilation air does not easily flow occurs on the surface of the radiation fin. Further, it becomes difficult to properly dissipate the heat radiation inside the electrical equipment box other than the radiation fins. Therefore, the size of the opening is 1/5 to 1/2 of the length of the heat sink in the same direction in the air flow direction, and is approximately the same length as the heat sink in the direction perpendicular to the air flow, or It is better to set it smaller.

FIG. 2 shows another embodiment of the present invention. As in FIG. 1, the electronic circuit board and the power element are housed in the electrical equipment box 1, and the heat radiation fins 3 of the heat sink are provided on the inner surface of the box.
Is attached. A forced ventilation fan 2 is provided on the other surface of the electrical equipment box 1. The electric equipment box 1 to which the heat radiation fins 3 are attached takes in ventilation air from the opening 4 of the electric equipment box on the side surface of the heat radiation fins, flows on the surface of the heat radiation fins 3 and discharges air from the forced ventilation fan 2. At this time, the heat of the radiation fin 3 and the heat of the substrate are simultaneously discharged.

The opening is provided to be slightly smaller than the approximate size of the side surface of the heat radiating fin so that the ventilation air can flow on the surface of the heat radiating fin so that the taken-in air flows through the gap between the fins. In FIG. 1 and FIG. 2, it is explained that the ventilation air enters through the opening of the electrical equipment box and is discharged through the forced ventilation fan. However, contrary to this route, it is taken in by the fan and is discharged from the front portion of the electrical equipment box. It may be done.

[0013]

As described above, according to the present invention, in the electrical equipment box having the electronic circuit board and the heat sink for radiating the power element, which is equipped with the forced ventilation fan, the heat sink is incorporated inside the box to provide the heat sink and the electronic device. The circuit board is housed in a common electrical equipment box, and the heat released from the power element and the parts on the board is exhausted by the forced ventilation fan so that the forced ventilation air can pass through the heat dissipation fin surface of the heat sink well. This allows the heat emitted from the substrate and the heat emitted from the power element to be simultaneously discharged by the common ventilation fan.

[Brief description of the drawings]

FIG. 1 shows an electrical equipment box showing an embodiment of the present invention.

FIG. 2 shows an electrical equipment box showing another embodiment of the present invention.

[Explanation of symbols]

 1 ... Electrical equipment box 2 ... Forced ventilation fan 3 ... Radiating fin 4 ... Opening

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Takashi Ogawa 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (4)

[Claims] 1. An electrical equipment box having an electronic circuit board and a heat sink for radiating heat of a power element, which has a forced ventilation fan, wherein the heat sink is incorporated inside the box. 2. The electrical equipment box for an electronic circuit device according to claim 1, wherein a ventilating air intake port is provided in a radiation fin portion of a heat sink of the electrical equipment box. 3. The intake port for ventilation air of the electrical equipment box is in front of the heat dissipation fins of the heat sink, and in the air flow direction of the heat sink, ⅕ to 1 of the length of the heat sink in the same direction.
3. The electrical component box of the electronic circuit device according to claim 2, wherein the heat sink is provided in the upstream portion of the air flow in a direction substantially perpendicular to the air flow and having a size substantially equal to or smaller than the length of the heat sink in the same direction. . 4. The electrical equipment box of an electronic circuit device according to claim 2, wherein the intake port for ventilation air of the electrical equipment box is a closed portion on the side surface of the heat radiation fin of the heat sink, which is smaller than the approximate size of the side surface. .