JPS6331401Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention relates to a semiconductor device in which a semiconductor element for power conversion and its control circuit are housed.

[Prior art and its problems]

An example of a semiconductor device for power conversion is a so-called semiconductor device that can operate an induction motor at a required speed.
There is a VVVF inverter device, which includes a rectifier that converts AC power to DC power, an inverter that converts this DC power to AC power with the required frequency and voltage, and a control circuit to control this inverter. It consists of a power supply for this control circuit, a smoothing capacitor installed in the DC intermediate circuit, etc., and these components are often integrated and stored in one box for convenient handling. .

By the way, there are various combinations of the size and number of semiconductor elements that perform power conversion in this semiconductor device, depending on whether the AC circuit is single-phase or three-phase, and the size and voltage of the induction motor. Since boxes of various sizes are required, there is a drawback that the number of types of parts that make up the box increases.

In addition, semiconductor elements for power conversion that make up rectifiers and inverters are generally forced to cool, except for small-capacity semiconductor elements, in order to prevent the temperature of the semiconductor elements from exceeding a permissible value due to heat generation during operation. This is necessary, and a forced cooling method that removes the heat generated by blowing air with a fan is often used. However, such forced air cooling methods cause inconveniences due to contamination, since air is blown even to control circuits such as printed circuit boards that do not require cooling. Therefore, attempts are made to store these circuits and components in a box so that no air is blown onto them, and to forcefully cool only the semiconductor elements for power conversion, but it is difficult to close off the external line terminals. As mentioned above, the size and number of power conversion semiconductor elements vary widely, and therefore the number of components of the box that houses them increases, resulting in an increase in cost.

[Purpose of invention]

Despite the wide variety of sizes and quantities of semiconductor elements for power conversion, this idea allows for forced air cooling of only the semiconductor elements for power conversion, and does not blow air to other control circuits or components. The purpose of the present invention is to provide a semiconductor device that can be constructed from various parts.

[Key points of the idea]

This idea deals with changes in the size and quantity of semiconductor elements for power conversion by cutting the bottom plate material and side plate material on which long cooling fins are formed into the required length. End plates are attached to both ends of the bottom plate and side plates with the cooling fins on the outside to form a box, and the control circuit components and printed circuit board are stored inside this box. The entire box can be closed by protruding the printed board terminals installed on the printed board and closing the openings with the printed board, so if air is blown to the cooling fins on the outside of the box, The power conversion semiconductor element attached to the bottom plate inside the box will be cooled. In addition, the control circuit such as a printed board and its components are housed inside the box, so there is no risk of contamination. In this way, by cutting a long material to a required length and using it, it is possible to supply boxes of various sizes with only a few types of members, and to improve the closure performance of the box.

[Example of idea]

FIG. 1 is a structural diagram showing an embodiment of the present invention,
The content of the present invention will be explained below with reference to this structural diagram.

In FIG. 1, the bottom plate 10 is made of a material with good thermal conductivity, such as aluminum, and a semiconductor element 12 for power conversion is attached to one side, while cooling fins 11 are formed on the other side. has been done. This bottom plate may be cast, but it is preferable to make it as long as possible by rolling, drawing, extrusion, etc. By the above-mentioned processing method, the cooling fins 11 are naturally formed continuously in the longitudinal direction. The side plate 20 is also manufactured as a long piece by the same processing method as the above-mentioned bottom plate 10, but one surface of this side plate 20 has a fitting uneven part into which the side part of the above-mentioned bottom plate 10 fits. 21 are formed continuously in the longitudinal direction. Furthermore, this fitting uneven portion 21 is provided on the side plate 20.
a circular hole 22 partially cut out on the same surface as the
A rectangular hole 23, also partially cut out, is formed continuously in the longitudinal direction.

The bottom area of the box that houses the semiconductor device is determined mostly by the size of the power conversion semiconductor elements 12 and the number of the elements. For example, in a VVVF inverter device that is connected to an AC power source and can operate an induction motor at a required speed, the size and number of diodes that make up the rectifier that converts the AC power to DC, and the conversion of this DC power to AC power are important. The size and quantity of the transistors that are the constituent elements of the inverter determine the size of the box mentioned above.
However, the size and number of these semiconductor elements 12 for power conversion differ greatly depending on whether the AC circuit is single-phase or three-phase, and how many of these semiconductor elements 12 are connected in series or in parallel. This can be achieved by cutting the bottom plate 10 and side plates 20 to the required length. Therefore, the bottom plate 10 is arranged so that the cooling fins 11 are on the outside.
By fitting the side plates 20 on both sides of the box, the bottom and sides of the box with the required length are formed.

In order to form a box body with an open top by cutting the bottom plate 10 and the side plates 20 to a required length and assembling them together as described above and attaching the upper end plate 30 and the lower end plate 40 thereto, Although it is necessary to create mounting holes for attaching the upper end plate 30 and the lower end plate 40 each time, in the case of the present invention, the side plate 20
Since notched circular holes 22 are continuously formed in the longitudinal direction, the tapping screws 39 are screwed through the mounting holes 31 previously provided at positions corresponding to the circular holes 22 in the upper end plate 30. When inserted, a thread is formed on the inner surface of the circular hole 22, so that the upper end plate 30 is tightened to the side plate 20. Similarly, by screwing the tapping screw 49 into the notched circular hole 22 of the side plate 20 through the mounting hole 41 provided in the lower end plate 40, the lower end plate 40 is also tightened to the side plate 20, and the upper surface is opened. A closed box body can be easily assembled by attaching a lid 60 to the top surface of the box body. A component that generates heat, that is, a semiconductor element for power conversion 12 is located on the bottom plate 1 inside this box.
0, and by blowing air through the cooling fins 11 provided on the opposite side of the bottom plate 10, the heat from the semiconductor element 12 is removed and its temperature can be kept below the allowable value.

The control circuit is mounted on a printed board 50, and this printed board 50 is mounted on the side board 20 by using a notched rectangular hole 23 provided in the side board 20 via an L-shaped printed board mounting bracket 52, for example. mounted on. In other words, this rectangular hole 2
3 into the rectangular hole 23, and tighten the aforementioned hexagonal nut with a screw through the mounting bracket 52, the printed board 50 can be fixed at a desired position.

A main circuit terminal 42 is provided on the lower end plate 40, and the conductive wire from the power conversion semiconductor element 12 is led out of the box via this main circuit terminal 42. Furthermore, this lower end plate is provided with an opening 43 for protruding the printed board terminal 51, so if the dimensions and tightening position of the aforementioned printed board mounting bracket 52 are appropriately adjusted, this opening 43 can be opened. The printed board terminal 51 can be correctly projected,
This opening 43 can also be closed with the printed board 50.
Further, a fan 44 is attached to the lower end plate 40 to blow air to the cooling fins 11. In addition, the main body of a large component such as the smoothing capacitor 45 is placed outside to cool it, and the terminal portion of the capacitor 45 is placed inside the box.

FIG. 2 is a partial sectional view of the lower end plate according to an embodiment of the present invention. The lower end plate 40 has a structure in which a portion thereof is divided into 40A. This lower end plate 40 is provided with a main circuit terminal 42 and further has an opening 43.
A printed board terminal 51 protrudes from the opening 43, but the opening 43 is closed by the printed board 50. Both sides of the terminal portion of this printed board 50 are supported by projections from the divided lower end plate 40A, and are tightened with tightening screws 53.

[Effect of idea]

According to this invention, among the parts constituting the box for storing semiconductor devices, the bottom plate and side plates are made of long materials cut to the required length, so the box can be used in many different sizes. However, there is no increase in the number of parts, and there is no need to drill the mounting holes required when cutting long materials and assembling the box. Instead, the tapping screws can be screwed into the circular holes with notches provided in the side panels. Since the box can be assembled easily, it has the advantage of reducing the cost of manufacturing the box.

Furthermore, the terminals for the control circuit can be used as they are on the printed board, and the printed board itself has a structure that closes the terminal section, so the semiconductor element and its control circuit can be housed. Since the closed nature of the box body is not lost, contamination due to intrusion of outside air can be prevented and the cost of the control circuit terminal portion can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram showing an embodiment of the present invention,
FIG. 2 is also an embodiment of the present invention, and shows a partial sectional view of the lower end plate. 10... Bottom plate, 11... Cooling fin, 12...
Semiconductor element for power conversion, 20... side plate, 21...
Fitting uneven part, 22...circular hole with notch,
23... Rectangular hole with notch, 30... Upper end plate, 31... Mounting hole, 39... Tapping screw,
40...lower end plate, 40A...divided lower end plate,
41...Mounting hole, 42...Main circuit terminal, 43...
Opening, 44... Fan, 45... Smoothing capacitor, 49... Tapping screw, 50... Printed board, 51... Printed board terminal, 52... Printed board mounting bracket, 53... Tightening screw, 60... lid.

Claims (1)

[Scope of utility model registration request] A semiconductor device that converts power using a semiconductor element, its accessories, and a printed circuit board equipped with control electronic components, in which cooling fins are formed in the longitudinal direction on one side using a material with good thermal conductivity. A bottom plate obtained by cutting a long material into a predetermined length, a concave-convex hole on one side into which the side of the bottom plate fits, a partially cut-out circular hole, and a partially cut-out rectangular hole. A side plate obtained by cutting a long material formed continuously in the longitudinal direction into a predetermined length, and a cut of both side plates when the side plates are fitted on both sides of the bottom plate with the cooling fins facing outside. An upper end plate having mounting holes at positions corresponding to the notched circular holes, an opening having a main circuit terminal and through which a printed circuit board terminal can protrude, and a lower end having mounting holes at positions corresponding to the notched circular holes of the side plates. a board, a screw that is screwed into a circular hole with a notch in each side plate through the mounting holes in the upper end plate and the lower end plate to form a box whose front face is open; and a semiconductor element inside the box. A rectangular hole with a notch in the both side plates is used so that the terminal part of the printed board to be stored together with the board and its accessories is located in the opening of the lower end plate, and the opening is closed by the printed board. 1. A semiconductor device comprising: a printed board that is attached to the box; and a lid that closes the front surface of the box.