JP2003023777A - Inverter and motor integrated with inverter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce dimensions as a whole, improve heat radiation efficiency, and reduce electrical resistances of circuit board wirings. SOLUTION: Switching devices 24a-24c and 25a-25c are grouped into high- potential side devices and low potential side devices. The high-potential side switching devices 24a-24c, and the low-potential side switching devices 25a-25c are arranged, so as to face each other and, further, the high-potential side and low-potential side switching devices 24a-24c and 25a-25c are attached to a common heat-radiating member 23. With such a constitution, the switching devices 24a-24c and 25a-25c are arranged, not only in one direction but also in a direction perpendicular to it, so that the dimensions can be reduced as a whole. In addition, according to the construction, the heat-radiating member 23 has an approximately square shape, and its heat radiation area will be increased. Moreover, wiring patterns of a printed wiring board 21 can be shortened and simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter having an improved arrangement structure of components and an inverter-integrated motor having the inverter integrally formed.

[0002]

2. Description of the Related Art In recent years, for example, in a motor drive type household electric device, drive power is supplied to the drive motor by an inverter. 11 and 1
2 shows the conventional structure of the inverter, in which the required number of switching elements 2a, 3a,
2b, 3b, 2c and 3c are arranged in a linear arrangement in the upper and lower parts of FIG.
A heat radiation plate 4 common to a, ... Is attached by screws 5, 5 ,. Further, the connection terminal 6 is provided beside the switching elements 2a, 3a, ... (On the side opposite to the heat sink 4 side).
a, 6b, 6c are mounted in an array in parallel with the arrangement of the switching elements 2a, 3a, ....

In FIG. 12, 7 is a switching element 2.
Leads used for mounting a, 3a, ..., 8 are connection terminals 6a
6A to 6C show leads used for mounting, and connection terminals 6
a to 6c are terminal boards 9 each having its lead 8
In addition, a screw 10 for tightening and connecting a connection terminal (for example, a coil outlet terminal of a drive motor) of a load (not shown) is screwed and included.

The switching elements 2a, 3a, ...
For example, in a power MOSFET, as shown in FIG. 13, each has a gate G, a drain D, and a source S,
There are three leads 7 corresponding to them. Then, the drains D of the switching elements 2a, 2b, 2c are connected to the high potential (+) side of the power supply, and the switching elements 3a, 2a and 2c are connected to the low potential (−) side of the power supply.
The sources S of 3b and 3c are connected. The sources S of the switching elements 2a to 2c are connected to the drains D of the switching elements 3a to 3c, respectively, and the connection terminals 6a to 6c are connected to the respective connection portions. Reference numeral 11 indicates a gate control circuit,
Each gate G of the switching elements 2a, 3a, ... Is connected to this and controlled.

FIG. 14 shows a wiring pattern on the back surface of the printed wiring board 1 which is used for other connections except the connection of the gates G of the switching elements 2a, 3a, ... To the gate control circuit 12 described above. 12a is a wiring pattern provided for connection between the high potential (+) side of the power source and each drain D of the switching elements 2a to 2c, and 12b is the low potential (−) side of the power source and each source S of the switching elements 3a to 3c. The wiring pattern 12c for connection of the switching elements 2a to 2c and the switching element 3a.
To 3c, connection with each drain D and connection terminals 6a to 6c
The wiring pattern used for the connection of c is shown. In FIG. 14, the gates G, drains D, and sources S of the switching elements 2a, 3a, ... Are represented by letters G, D, and S, respectively, in order to make the connections easy to understand.

[0006]

The above-mentioned conventional ones have the following problems. 1. Since the switching elements 2a, 3a, ... Are arranged in a straight line, the heat sink 4 and the printed wiring board 1,
As a result, the entire inverter extends in the direction of the straight line and becomes large.

2. The heat radiating plate 4 extending in the direction in which the switching elements 2a, 3a, ... Arrange is elongated, and as a result, the heat radiating plate 4 has a smaller area for the peripheral length, and the heat radiating efficiency of the switching elements 2a, 3a ,. Is bad. 3. Wiring patterns 12a and 12b of the printed wiring board 1
Becomes longer as shown in FIG. 14, and the wiring pattern 12a
Becomes complicated, and these wiring patterns 12a, 12b
Has a large electric resistance and a large loss.

The present invention has been made in view of the above circumstances. Therefore, an object of the present invention is to provide an inverter capable of downsizing the entire size, improving heat dissipation efficiency, and reducing electric resistance of circuit board wiring, Another object is to provide an inverter-integrated motor that can be further miniaturized.

[0009]

In order to achieve the above object, an inverter of the present invention is configured by mounting a plurality of switching elements on a circuit board, wherein the switching elements are arranged on a high potential side and a low potential side. The high potential side switching element and the low potential side switching element are arranged to face each other, and the high potential side and low potential side switching elements are attached to a common heat radiating member. Invention of Item 1).

According to this structure, the plurality of switching elements are arranged not only in one direction but also in a direction orthogonal to the one direction, so that the extension in only one direction is suppressed and the size is reduced. Further, along with this, the heat dissipation member becomes closer to a square, and the area is increased for the peripheral length, so that the heat dissipation efficiency is improved. Further, the circuit board wiring is also short and simple, and the electric resistance is small.

In this case, a connection terminal for connecting a load may be arranged in the facing gap between the high potential switching element and the low potential switching element (claim 2).
Invention). With this structure, the necessary elements such as the high-potential side switching element, the low-potential side switching element, and the connection terminal can be arranged efficiently and compactly.

Further, it is preferable that the heat dissipating member has a plate shape, the heat dissipating member is disposed in parallel with the circuit board, and the switching element is disposed on the heat dissipating member (invention of claim 3). In this case, since the plate-shaped heat dissipation member is arranged in parallel with the circuit board, the entire surface can be flattened.

Further, it is also possible to dispose a plate-shaped heat dissipation member in parallel with the circuit board and dispose the switching element between them (the invention of claim 4). With this structure, it is possible to flatten the entire structure, and it is not necessary to provide holes in the heat dissipation member to avoid interference with the leads of the switching element, which facilitates formation of the heat dissipation member. Further, in this case, since it is not necessary to provide the hole in the heat dissipation member, the heat dissipation area of the heat dissipation member is increased, and the heat dissipation efficiency is further improved.

In addition, the switching elements may be bridge-connected, and a plurality of switching elements may be connected in parallel for each arm thereof (the invention of claim 5). With this device, the output of the inverter can be increased, and by itself, it is possible to reduce the overall size, improve the heat dissipation efficiency, and reduce the electric resistance of the circuit board wiring.

In the inverter-integrated motor of the present invention, the switching element is attached to the motor case,
The case of this motor is a heat dissipation member (the invention of claim 6). With this, in the motor equipped with the inverter which can be miniaturized as described above, a separate heat dissipating member is not required, and the motor can be further miniaturized.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. First, in FIGS. 1 and 2, reference numeral 21 denotes a circuit board, especially a printed wiring board, which has a substantially square shape. On the back surface of the printed wiring board 21, as shown in FIG. 3, wiring patterns 22a, 22b, 22c, which are circuit board wirings,
22d is provided.

On the other hand, on the front side of the printed wiring board 21, the single heat dissipation member 23 shown in FIGS. 1 and 2 and the switching elements 24a, 24b, 24c, 25a, 25 are provided.
b, 25c and connection terminals 26a, 26b, 26c are arranged. Of these, the heat dissipation member 23 is made of a material having a high thermal conductivity such as aluminum and is formed in a plate shape that is close to a square or a horizontally long rectangle in the figure. It has the hole 27 which forms. Then, on the front side of the printed wiring board 21, such a heat dissipation member 23 is arranged in close contact with the printed wiring board 21 in parallel.

On the other hand, the switching elements 24a to 24c,
25a to 25c are, for example, MOSFETs, especially power MOSFETs, and have three leads 28 and 29 respectively corresponding to the gate G, the drain D, and the source S shown in FIG. Here, the switching element 2
4a to 24c are switching elements on the high potential side (+ side of the power supply shown in FIG. 4), and switching elements 25a to 25c are switching elements on the low potential side (-side of the power supply shown in FIG. 4). As shown in FIGS. 1 and 2, the high and low potentials are divided and arranged on the front side of the printed wiring board 21 so as to face each other in the left and right directions in the drawing.

With this arrangement, the switching elements 24a to 24c on the high potential side and the switching elements 25a to 25c on the low potential side are printed with the leads 28 and 29 bent in the L shape from the hole 27 of the heat dissipation member 23. The wiring pattern 22a is inserted through the back side of the wiring board 21.
22c are mounted on the printed wiring board 21 by soldering (not shown) and connecting them.

Further, the switching elements 24a to 24c, 2
5a to 25c are arranged in close contact with and parallel to the upper surfaces of both sides of the heat dissipation member 23, and in this state, these switching elements 24a to 24c, 25a to 25c are attached to the heat dissipation member 23 by screws 30, 30 ,. ing. As a result, the switching elements 24a to 24c and 25a to 25
c is located on the printed wiring board 21 and the heat dissipation member 23 arranged in parallel with the printed wiring board 21.

Each of the connection terminals 26a to 26c is formed by projecting leads 32 under approximately four corners of a rectangular terminal plate 31, and the holes 27 of the heat dissipation member 23 face these.
The switching elements 24a to 24c, 25a to the switching elements 24a to 24c on the high potential side and the switching elements 25a to 25c on the low potential side face each other in the facing interval portion.
25c are arranged in parallel with each row.

Then, with this arrangement, the connection terminals 26a-2
6c shows each lead 32 in the same manner as the hole 2 of the heat dissipation member 23.
The printed wiring board 21 is mounted on the printed wiring board 21 by inserting the wiring pattern 22c from the back side of the printed wiring board 21 to the wiring pattern 22c by soldering (not shown). Each of the connection terminals 26a to 26c has a screw 33 for tightening and connecting a connection terminal (for example, a coil output terminal of a drive motor) of a load (not shown) at a central portion of the terminal plate 30. .

Further, as a result of the connection of the leads 28, 29 and the lead 31 to the wiring patterns 22a-22c,
As shown in FIG. 4, the drains D of the switching elements 24a to 24c are connected to the high potential (+) side of the power supply, and the switching elements 25a to 25c are connected to the low potential (−) side of the power supply.
Each source S of c is connected. The sources S of the switching elements 24a to 24c are connected to the drains D of the switching elements 25a to 25c, respectively, and the connection terminals 26a to 26c are connected to the respective connection parts. As a result, the switching elements 24a-2
4c, 25a to 25c, and connection terminals 26a to 26c
Are bridge connected.

In FIG. 4, reference numeral 34 denotes a gate control circuit, which has switching elements 24a to 24c, 2.
The gates 5a to 25c are connected to each other so that the switching elements 24a to 24c and 25a to 25c are controlled by the gate control circuit 34.

Therefore, the wiring pattern 22a is provided for connection between the high potential (+) side of the power source and each drain D of the switching elements 24a to 24c, and the wiring pattern 22b is connected to the low potential (-) side of the power source and the switching element. 25a to 25c
It is provided for connection with each source S of. In addition, the wiring pattern 22c is the source S of each of the switching elements 24a to 24c.
And the respective drains D of the switching elements 25a to 25c and the connection terminals 26a to 26c. The wiring pattern 22d is another necessary wiring pattern. And in FIG. 3, in order to make those connections easy to understand, the switching elements 24a to 24c, 25
The gates G, drains D, and sources S of a to 25c are represented by the letters G, D, and S, respectively.

As described above, in the present configuration, the switching elements 24a to 24c and 25a to 25c are divided into the high potential side and the low potential side, and the high potential side switching element 24a.
24c and low potential side switching elements 25a to 25c are arranged to face each other, and the high potential side and low potential side switching elements 24a to 24c and 25a to 25c are attached to a common heat dissipation member 23.

As a result, the plurality of switching elements 24
a to 24c and 25a to 25c are arranged not only in one direction like the conventional one but also in a direction orthogonal to it,
To that extent, the extension in only one direction can be suppressed, and the size can be reduced. Further, since the whole inverter can be miniaturized in this way, when the motor is mounted on a motor or the like, restrictions due to the shape are lessened and the mounting can be facilitated. Further, due to such a change in the arrangement of the switching elements 24a to 24c and 25a to 25c, the common heat radiation member 23 to which they are attached becomes closer to a square than a conventional long thin one, and therefore the area is increased relative to the peripheral length. The heat dissipation efficiency can be improved.

In addition, regarding the wiring patterns 22a to 22d of the printed wiring board 21, which are the wirings of the circuit board, as is apparent from the difference between FIG. 3 and FIG. 14, especially on the high potential (+) side of the power supply. Since the wiring pattern 22a and the wiring pattern 22b on the low-potential (−) side of the power supply can be provided separately for the high-potential side switching elements 24a to 24c and the low-potential side switching elements 25a to 25c, respectively. , Switching elements 2a, 3a, 2
b, 3b, 2c, 3c in a straight line, and the wiring pattern 12a on the high potential (+) side of the power supply and the wiring pattern 1 on the low potential (−) side of the power supply, which are provided correspondingly.
The wiring pattern 22a can be made shorter than 2b, and the wiring pattern 22a can be made simpler than the wiring pattern 12a, so that the electrical resistance of the wiring patterns 22a and 22b can be reduced and the loss can be reduced.

Further, particularly in the case of the above structure, the connection terminals 26a to 26c for connecting a load are provided at the facing gap portions between the high potential side switching elements 24a to 24c and the low potential side switching elements 25a to 25c. It is arranged. As a result, the switching elements 24a to
24c and switching elements 25a to 25 on the low potential side
Since the necessary parts such as c and the connection terminals 26a to 26c can be arranged efficiently and compactly, the overall size of the inverter can be further reduced.

Further, the heat radiating member 23 has a plate shape, the heat radiating member 23 is arranged in parallel with the printed wiring board 21, and the switching elements 24a to 24c, 25a to are arranged on the heat radiating member 23.
25c is arranged. In this configuration, since the plate-shaped heat dissipation member 23 is arranged in parallel with the printed wiring board 21, the entire structure can be flattened (thinned), and can be more easily mounted on the motor or the like.

In contrast to the above, FIGS. 5 to 10 show the second to fourth embodiments of the present invention.
The same parts as those of the embodiment are designated by the same reference numerals, and the description thereof will be omitted. Only different parts will be described.

[Second Embodiment] In the second embodiment shown in FIGS. 5 and 6, the high potential side switching elements 24a.about.
24c and low-potential-side switching elements 25a to 25c
And are arranged on the back side of the printed wiring board 21 and mounted,
In place of the above-mentioned heat dissipation member 23, a heat dissipation member 41 formed of a material having a high thermal conductivity such as aluminum and having a substantially square shape in the drawing or a horizontally long rectangle is used as the switching element 2
Printed wiring board 21 of 4a to 24c and 25a to 25c
It is arranged on the side opposite to the side, and the switching element 2
4a to 24c and 25a to 25c are attached.

In other words, in this case, the plate-shaped heat dissipation member 41 is arranged in parallel with the printed wiring board 21, and the switching elements 24a to 24c and 25a to 2 are arranged between them.
5c is arranged.

By doing so, the entire device can be flattened, and the heat dissipating member 41 is provided with the switching element 2.
It is not necessary to provide holes (holes 27 formed in the above-described heat dissipation member 23) for avoiding interference with the leads 28 and 29 of 4a to 24c and 25a to 25c and the leads 32 of the connection terminals 26a to 26c, and the heat dissipation member 41 Easy to form.
Further, in this case, since it is not necessary to provide the hole 27 in the heat dissipation member 41, the heat dissipation area of the heat dissipation member 41 is increased, and the heat dissipation efficiency can be further improved.

[Third Embodiment] In the third embodiment shown in FIGS. 7 and 8, switching elements 24a to 24c, 2 are provided.
Regarding the bridge connection circuit between 5a to 25c and the connection terminals 26a to 26c, switching elements 24a 'to 24c',
By adding 25a 'to 25c', a plurality (two in this case) of switching elements (for example, switching element 24a and switching element 24a ', switching element 24b and switching) are provided for each arm of the bridge connection circuit. The elements 24b ', ...) Are connected in parallel.

In particular, FIG. 8 shows a wiring pattern 22e of a printed wiring board (circuit board) 51 provided for parallel connection of two switching elements for each arm of such a bridge connection circuit. This is provided on the surface of the printed wiring board 51 in addition to the above-mentioned wiring patterns 22a to 22d.

By doing so, the output of the inverter can be increased, and the switching element 24 itself can be used.
a to 24c, 24a 'to 24c', 25a to 25c, 2
5a 'to 25c' are divided into a high potential side and a low potential side, and the high potential side switching elements 24a to 24c, 24a 'to
24c 'and low potential side switching elements 25a to 25c,
25a 'to 25c' are arranged to face each other, and the switching elements 24a to 24c, 2 on the high potential side and the low potential side are arranged.
4a 'to 24c', 25a to 25c, 25a 'to 25c
By attaching ′ to the common heat radiating member 52, it is possible to reduce the overall size, improve the heat radiating efficiency, and reduce the electric resistance of the wiring patterns 22a and 22b of the printed wiring board 51 as described above.

The switching elements 24a-24c,
24a 'to 24c', 25a to 25c, 25a 'to 25
In the example shown in FIG. 8, the arrangement of c ′ is two switching elements (for example, the switching element 24a and the switching element 2) for each arm of the bridge connection circuit.
4a ′, switching element 24b and switching element 2
4b ', ...) are arranged vertically in the figure, but they may be arranged horizontally as shown in FIG.

In FIG. 9, 22f shows a wiring pattern provided for parallel connection of two switching elements for each arm of the bridge connection circuit.
Is a printed wiring board which is a circuit board, and 62 is a heat dissipation member.

[Fourth Embodiment] In the fourth embodiment shown in FIG. 10, in a motor in which a stator 72 and a rotor 73 are built in a case 71 and a rotary shaft 74 is supported by bearings 75 and 76, Inverter switching element 24a-
24c, 25a to 25c (switching elements 24a, 2
5a is attached to the motor case 71 to attach the motor case 71 to the heat dissipation member 2 described above.
A heat radiation member is used instead of 3, 41, 52, and 62.

In this way, the switching elements 24a to 24c and 25a to 25c are arranged opposite to each other, so that the switching elements 24a to 24c and 25a to 25c can be downsized, the heat radiation efficiency can be improved, and the electric resistance of the wiring patterns 22a and 22b of the printed wiring board 21 can be reduced. Further, in a motor having a possible inverter, since the case 71 of the motor can be used as a heat dissipation member, a separate heat dissipation member is not required, and the motor can be further downsized.

In FIG. 10, reference numeral 77 is a connection terminal 2.
6a to 26c (only the connection terminal 26a is shown) and a connecting wire connecting the stator coil 72a of the motor, which is the load of the inverter, are shown, and 78 is a cover plate that covers the inverter. Besides, the present invention is not limited to the embodiments described above and shown in the drawings, and in particular, the switching element is not limited to the above-mentioned MOSFET.
For example, a GBT or a power transistor may be used, and appropriate modifications may be made without departing from the scope of the invention.

[0043]

As described above, according to the inverter of the present invention, the overall size can be reduced, the heat dissipation efficiency can be improved, the electric resistance of the circuit board wiring can be reduced, and the loss can be reduced. it can. Further, according to the inverter-integrated motor of the present invention, the size can be further reduced.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view taken along the line AA of FIG.

FIG. 3 is a diagram showing a wiring pattern on the back of a printed wiring board (circuit board).

[Fig. 4] Electrical connection diagram

FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 6 is a view corresponding to FIG. 2 (longitudinal sectional view taken along line BB in FIG. 5).

FIG. 7 is a view corresponding to FIG. 4, showing a third embodiment of the present invention.

FIG. 8 is a view equivalent to FIG.

FIG. 9 is a diagram showing an example of a different arrangement of switching elements.
Corresponding figure

FIG. 10 is a vertical sectional view of an inverter-integrated motor showing a third embodiment of the present invention.

FIG. 11 is a view corresponding to FIG. 1 showing a conventional example.

FIG. 12 is a view corresponding to FIG. 2 (longitudinal sectional view taken along the line CC in FIG. 11).

FIG. 13 is a view corresponding to FIG.

FIG. 14 is a view corresponding to FIG.

[Explanation of symbols]

Reference numeral 21 is a printed wiring board (circuit board), 23 is a heat dissipation member, 24a to 24c, 25a to 25c are switching elements, 26a to 26c are connection terminals, 41 is a heat dissipation member, 24
a'-24c ', 25a'-25c' are switching elements, 51 is a printed wiring board (circuit board), 52 is a heat dissipation member, 61 is a printed wiring board (circuit board), 62 is a heat dissipation member, and 71 is a motor case. Indicates.

Claims (6)

[Claims] 1. In an inverter configured by mounting a plurality of switching elements on a circuit board, the switching elements are divided into a high potential side and a low potential side, and the high potential side switching element and the low potential side switching element are provided. And a switching element on the high potential side and a switching element on the low potential side are attached to a common heat radiation member. 2. A connection terminal for connecting a load is arranged in a facing gap portion between the high potential side switching element and the low potential side switching element.
Inverter described. 3. The inverter according to claim 1, wherein the heat dissipation member has a plate shape, the heat dissipation member is arranged in parallel with the circuit board, and the switching element is arranged on the heat dissipation member. 4. The inverter according to claim 1, wherein the heat dissipation member has a plate shape, the heat dissipation member is arranged in parallel with the circuit board, and the switching element is arranged between them. 5. The inverter according to claim 1, wherein the switching elements are bridge-connected and each arm has a plurality of switching elements connected in parallel. 6. The motor integrated with an inverter according to claim 1, wherein the switching element is attached to a case of the motor, and the case of the motor serves as a heat dissipation member.