JPH0898557A - Inverter device - Google Patents

Abstract

PURPOSE: To obtain an inverter device which circulates generated heat radiated inside a case and distributes a temperature uniformly by a method wherein a cooling fin is installed at the rear in the deep bottom part of the case, an open-air cooling fan is installed at the rear in the shallow bottom part of the case and an inside-air cooling fan is installed at the end part of a printed-wiring board for a main circuit. CONSTITUTION: When an inside-air cooling fan 12 and an open-air cooling fan 3 are driven, the inside air inside a case 1 passes through a space between a printed-wiring board 5 for a main circuit and the deep bottom part 1a of a case from an evacuation port 14 so as to deprive heat generated from a semiconductor element 11; it flows through an inclination part 1c; it hits a sidewall 1d; the heat of the inside air is given to, and received by, the sidewall; the cool air from the cooling fan 3 passes through the outside of the inclination part 1c; it is circulated between cooling fins 2 at the rear of the deep bottom part 1a; and the case 1 is cooled. The inside air which has hit the sidewall is circulated in a space between the printed-wiring board 5 for the main circuit and an electromagnetic shield plate 7 to enter the inside-air cooling fan 12 from an intake port 13. In this manner, the inside air is circulated, and the heat inside the case 1 is dispersed uniformly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter device for mounting a semiconductor element and accommodating a printed wiring board.

[0002]

2. Description of the Related Art Conventionally, this type is constructed as shown in FIG. Reference numeral 21 is a case having a fin 21a for heat dissipation on the back surface, 22 is a cover, 23 is a semiconductor element fixed to the bottom plate of the case, 24 is a wiring board for a main circuit on which electronic parts are mounted and printed wiring is provided between the parts, and is planted in the case. It is fixed to the provided stud 25 with a bolt. Reference numeral 26 is an electromagnetic shield plate made of a metal plate, which is fixed to a stud 27 planted in the case with a bolt. Reference numeral 28 denotes a control circuit wiring board on which electronic components are mounted and printed by wiring the components to each other. Reference numeral 30 is a stud, one end of which is fixed to the electromagnetic shield plate, and an operation console 31 is attached to the other end.

In the inverter device configured as described above, the heat generated from the semiconductor element was conducted to the heat dissipation fin heat sink and dissipated from the heat dissipation fin heat sink. However, sufficient cooling can be performed. could not. For this reason, there is also one that attaches a cooling fan to the heat dissipation fin and forcibly cools it by applying cooling air to the heat dissipation fin, but the heat generated from the semiconductor element is dissipated in the case as radiant heat,
There is a drawback in that the electrical components on the wiring board for the main circuit are affected by heat and the electrical components malfunction. The present invention has been made to eliminate the above-mentioned conventional drawbacks, and an object of the present invention is to circulate the heat generated in the case with a cooling fan to make the temperature distribution uniform and improve the cooling effect. To do.

[0004]

In order to achieve the above object, the present invention provides a main circuit printed wiring board having a case made of a good heat conducting material, on which electrical parts constituting a main circuit of an inverter device are mounted, and a control circuit. In an inverter device that houses a control circuit printed wiring board on which the electrical components constituting the
A case having a deep bottom and a shallow bottom formed by forming bottom plates in different steps, a semiconductor element mounted on the deep bottom of the case, a cooling fin provided on the back of the deep bottom of the case, and an outside air cooling fan mounted on the back of the shallow bottom of the case. A main circuit printed wiring board mounted on the case with a space on the bottom plate of the case; a printed circuit board for control circuit mounted on the case with a space on the main circuit printed wiring board; and a main circuit printed wiring An inside air cooling fan fixed to the case is provided at the end of the plate.

[0005]

When the inside air cooling fan and the outside air cooling fan are driven by the above means, the heat generated from the semiconductor element is circulated in the case by the inside air cooling fan to make the heat uniform and to dissipate from the side wall of the case. Further, the outside air cooling fan vents the cooling fins to cool them.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows a side cross-sectional view. Reference numeral 1 denotes a case formed by die-casting a good heat conductor such as an aluminum alloy. The bottom surface of this case is formed in a staggered manner to form a deep bottom portion 1a, a shallow bottom portion 1b, and an inclined portion 1c. It is provided with a side wall 1d surrounding the bottom surface. A cooling fin 2 is provided on the back surface of the deep bottom portion 1a of the case.
And an outside air cooling fan 3 is attached to the back surface of the shallow bottom portion 1b. Reference numeral 4 denotes a cover that protects internal parts such as a printed wiring board, and a case is formed in a hermetically sealed structure by interposing packing between the case and the case. Reference numeral 5 is a main circuit printed wiring board on which electric parts constituting the main circuit of the inverter device are mounted, and is fixed to a stud 6 provided on the case with a screw.
An electromagnetic shield plate 7 made of a metal plate is fixed to a mounting seat 8 provided on the case with screws. Reference numeral 9 is a printed wiring board for a control circuit on which electric parts constituting the control circuit are mounted, which is fixed with screws via a spacer 10. Reference numeral 11 is a semiconductor element attached to the deep bottom portion 1a of the case, 12 is an inside air cooling fan provided in the case, 13 is an intake port provided in a partition plate in the case, and 14 is an exhaust port provided in the partition plate in the case. is there. In the inverter device configured as described above, heat generated from the semiconductor element is conducted to the case and the cooling fins and is also dissipated in the case. Now, when the inside air cooling fan 12 and the outside air cooling fan 3 are driven, the inside air in the case passes through the space between the main circuit printed wiring board 5 and the deep bottom part 1a of the case from the exhaust port 14 provided in the partition plate of the case. The heat generated from the semiconductor element 11 is taken away to increase the wind speed and flow through the inclined portion 1c to hit the side wall 1d to transfer the heat of the inside air to the side wall. The case is cooled by flowing through the cooling fins 2 on the back surface of 1a. The inside air hitting the side wall flows through the space between the main circuit printed wiring board 5 and the electromagnetic shield plate 7 and enters the inside air cooling fan through the intake port 13 provided in the partition plate. In this way, the inside air is circulated to efficiently transfer the heat in the case to the case and to evenly disperse the heat in the case.

[0007]

As described above, according to the present invention, the internal air in the case is circulated to dissipate the internal heat from the bottom and side walls of the case, and the heat in the case is evenly dispersed, so that it stays locally. It is possible to reduce wear of the electric component due to heat.

[Brief description of drawings]

FIG. 1 is a side sectional view of an inverter device of the present invention.

FIG. 2 is a side sectional view of a conventional inverter device.

[Explanation of symbols]

1 Case 1a Deep bottom 1b Shallow bottom 1c
Inclined portion 2 Cooling fin 3 Outside air cooling fan 4 Cover 5 Main circuit printed wiring board 7 Electromagnetic shield plate 9 Control circuit printed wiring board 11 Semiconductor element 1
2 Inside air cooling fan 13 Intake port 14 Exhaust port

Claims (1)

[Claims] 1. A printed wiring board for a main circuit, in which an electric component forming a main circuit of an inverter device is mounted in a case made of a good heat conductive material, and a printed wiring board for a control circuit mounting electric components forming a control circuit. In the inverter device that accommodates the case, a case having a deep bottom part and a shallow bottom part with bottom plates formed in different steps, a semiconductor element attached to the case deep bottom part, a cooling fin provided on the back surface of the case deep bottom part, and a case shallow bottom part Outside air cooling fan mounted on the back, the main circuit printed wiring board mounted on the case with a space between the bottom plate of the case, and the printed wiring for the control circuit mounted on the case with a space in the main circuit printed wiring board. Inverter device characterized in that a board and an inside air cooling fan provided at an end of the main circuit printed wiring board and fixed to a case are provided.