JP2000332174A - Motor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To downsize an apparatus, without obstructing heat radiation by forming a housing with a heat sink disposed on the back side of a circuit board having a control circuit and setting a power element in the housing. SOLUTION: A housing 3a is disposed between a printed board 2 and a heat sink 3, a part of which is bulged outward to form a recess. A power element 1 is fixed to the housing 3a with screws 4, to directly contact the power element 1 to the heat sink 3. The power element 1 is electrically connected to the printed board 2 with solder 5 through a terminal 1a of the power element 1, where the lead forming is applied to a through-hole 2b of the printed board 2. The printed board 2 is fixed to the heat sink 3 with screws. An insert-formed case 6 and a cover 7 house and protect the power element 1, the printed board 2 and the heat sink 3. Externals such as motors and power sources are connected, and the heat sink 3 is fastened tightly to the case 6, and the case 6 is fastened tightly to the cover 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor control device for controlling the number of rotations of a motor.

[0002]

2. Description of the Related Art A conventional motor control device will be described below. FIG. 4 shows a conventional motor control device. In this figure, 101 is a power element for applying a controlled voltage to the motor, and 102 is a printed circuit on which a circuit for controlling the power element 101 is mounted. A board 102a is a lead frame for connecting a control circuit mounted on the printed board 102 to an insert included in the case 106, and 103 is a power element 101
Heat sink for radiating heat generated from
4 is a screw for fixing the power element 101 to the heat sink 103; 105 is a solder for connecting the power element 101 and the printed circuit board 102 via the terminal 101a;
Reference numeral 106 denotes a case made of insert-molded resin for housing and protecting the power element 101, the printed circuit board 102, and the heat sink 103, and 107 denotes a cover made of resin.

Next, the structure of a conventional motor control circuit will be described. When the power element 101 for applying a controlled voltage to the motor is mounted on a printed circuit board 102 on which a circuit for controlling the power element 101 is mounted, the generated heat cannot be sufficiently dissipated. May exceed the heat resistant temperature of Therefore, it has been found that the power element 101 can efficiently dissipate heat when attached directly to the heat sink 103.

Further, since the power element 101 needs to be electrically connected to the printed circuit board 102, the upper surface of a substantially flat heat sink 103 made of aluminum die-cast and arranged to extend on the plane of the printed circuit board 102 is provided. The terminal 101 a connected to the power element 101 is fixed to the printed circuit board 102 by solder 105. Note that the printed circuit board 102 and the heat sink 103 were fixed by screws not shown.

The power element 101 and the printed circuit board 10
2 as well as housing and protecting the heat sink 103;
The heat sink 103 and the case 106, and the case 106 and the cover 107 are fixed with an adhesive, respectively, and are connected to the lead frame 102a and the case 106 mounted on the printed circuit board 102, respectively. The insert 106a formed integrally was connected by welding.

[0006] Another conventional technique, Japanese Utility Model Application Laid-Open No.
Japanese Patent Publication No. 165853 discloses an opening in a printed board,
A structure in which transistors are fitted in these openings, a heat dissipation area is secured, and the heatsink is configured to have a large area along the printed board, thereby increasing the density of printed boards arranged in multiple stages. Techniques that allow implementation are disclosed.

[0007]

In the conventional motor control device, the power element is arranged on the upper surface of the heat sink, and the printed circuit board is also arranged on the upper surface of the heat sink. And the planar shape of the device itself has also increased. Therefore, there is a problem that the motor control device according to the conventional technique has poor mounting layout.

The present invention has been made to solve the above-described problems, and has as its object to obtain a small-sized motor control device without obstructing heat radiation of a power element.

[0009]

A motor control device according to the present invention includes a substrate having a control circuit, a heat sink disposed on the back side of the substrate, and a power element for applying a voltage corresponding to the control circuit to the motor. In the motor control device, a housing is formed by the substrate and the heat sink, and the power element is disposed on one surface of the heat sink in the housing.

[0010] The motor control device according to the present invention includes:
In addition to the above-described configuration, one surface of the heat sink has a concave shape, and a housing portion is configured by a concave portion of one surface of the heat sink on which the power element is arranged and the substrate.

Further, in the motor control device according to the present invention, in addition to the above-described structure, the heat sink has a flat plate shape and is fixed to a case for fixing the substrate at a predetermined distance from the substrate, and the power element Are disposed in a storage section surrounded by one surface of the heat sink, the substrate, and the inner surface of the case.

[0012] The motor control device according to the present invention includes:
In addition to the above configuration, the heat sink has a flat plate shape, and is fixed by a housing fixing member at a predetermined distance from the substrate, and a power element is fixed to one surface of the heat sink, the substrate and the housing. It is arranged in a storage section surrounded by the inner surface of the member.

Further, in the motor control device according to the present invention, in the above configuration, the substrate is a printed circuit board.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1. Next, a motor control device according to the present invention will be described with reference to FIG. In FIG. 1, reference numeral 1 denotes a power element for applying a controlled voltage to a motor, 1a denotes a terminal for connecting the power element to a printed circuit board 2, and 2a denotes a control circuit mounted on the printed circuit board 2. The lead frame 2b for connecting to the wiring is a through hole provided in the printed circuit board 2, through the terminal 1a, and connecting the terminal 1a and the wiring of the printed circuit board 2 by solder 5.

Reference numeral 3 denotes a heat sink made of metal such as aluminum die-cast, 3a denotes a housing for the power element 1 provided on the heat sink 3, 4 denotes a screw for fixing the power element 1 to the heat sink 3, and 6 denotes a power element. 1, a case made of insert-molded resin for accommodating and protecting the printed circuit board 2 and the heat sink 3; and 7, a cover made of resin.

Next, the structure of the motor control device according to the present invention will be described in detail. When the power element 1 for applying a controlled voltage to the motor is mounted on the printed circuit board 2, heat generated from the power element 1 cannot be sufficiently dissipated, and the heat resistance of the printed circuit board 2 may be exceeded. Therefore, it is necessary to adopt a structure directly attached on the heat sink 3. In the motor control device according to the present invention, the housing 3a is formed between the printed circuit board 2 and the heat sink 3 by forming a concave portion by expanding a part of the heat sink 3 outward, and the power element 1 is formed in the housing 3
The power element 1 and the heat sink 3 are in direct contact with each other by being fixed to the screw a. The electrical connection between the power element 1 and the printed board 2 is made by solder 5 through the terminal 1a of the power element 1 which has been subjected to lead forming in a through hole 2b provided in the printed board 2.

The printed circuit board 2 is fixed by screws not shown on the heat sink 3. The insert-molded case 6 and cover 7 are provided for housing and protecting the power element 1, the printed circuit board 2, and the heat sink 3, and for connecting to the outside such as a motor and a power supply. And case 6
And the cover 7 are connected and fixed by an adhesive, respectively. The lead frame 2a mounted on the printed board 2 and the insert 6a integrally formed in the case 6 are connected by welding.

The motor control device thus formed is
By providing the storage portion 3a in the heat sink 3 and disposing the power element 1 between the printed board 2 and the upper surface of the heat sink 3, the planar shape of the heat sink 3 can be reduced. Therefore, even when viewed as a whole of the motor control device, the planar shape can be reduced, and the obtained motor control device can be reduced in size and the layout can be improved. In addition, heat sink 3
Is not a flat plate but a surface on which the power element 1 is arranged (FIG. 1).
(The upper surface indicated by) has a concave shape, it is possible to secure a surface area without enlarging the planar shape, and does not hinder heat radiation.

Although the motor control device shown in FIG. 1 does not include a mounting portion for forming a screw hole or the like for mounting the device, the motor control device has a screw hole opened along the mounting surface. Parts need to be provided. Further, in the above description, the example in which the substrate on which the control circuit is mounted is the printed circuit board 2 is shown. However, the use of a ceramic substrate also enables the size of the obtained motor control circuit to be similarly reduced, and It goes without saying that the layout can be improved.

Second Embodiment Next, a second embodiment of the motor control device according to the present invention will be described with reference to FIG. In the first embodiment already described, a motor control device having a structure in which a recess is formed in the heat sink 3 to form the storage portion 3 a by the recess, and the storage portion 3 a is surrounded by the heat sink 3 and the back surface of the printed circuit board 2. However, in the second embodiment,
An example of a motor control device using heat sinks of different shapes is shown.

In FIG. 2, reference numeral 3b denotes a flat heat sink, and 6a denotes a printed board 2 and a flat plate so as to secure a housing 3a for disposing the power element 1 between the printed board 2 and the heat sink 3b. And a case for fixing the heat sink 3b, respectively.
The same reference numerals as those already used for the description indicate the same or corresponding parts.

When the flat heat sink 3b is used,
The storage portion 3a is provided between the back surface of the printed circuit board 2 and the heat sink 3b.
And the inner surface of the case 6a. The motor control device configured as described above can also reduce the planar shape similarly to the motor control device described in the first embodiment, and can reduce the size of the motor control device.

Embodiment 3 Next, FIG. 3 is a sectional view of a motor control device according to Embodiment 3 of the present invention.
Will be described. Embodiments 1 and 2 described above
In this case, the housing portion 3a for housing the power element 1 is surrounded by the upper surface of the heat sink 3 and the back surface of the printed circuit board 2, or by the upper surface of the flat heat sink 3b, the back surface of the printed circuit board 2 and the inner surface of the case 6a. In the third embodiment, another storage unit 3 is provided.
The configuration of a is shown.

In FIG. 3, reference numeral 3c denotes a flat plate-shaped heat sink on which the power element 1 is disposed, 6b denotes a case for fixing the printed circuit board 2 and accommodating components of the motor control device, and 8 denotes a case for the printed circuit board 2. This is a housing component constituting member disposed between the back surface and the upper surface of the heat sink 3c. In addition, the same reference numerals as those already used for the description indicate the same or corresponding parts.

The housing 3a of the motor control device according to the third embodiment is provided
c and the surface of the housing component member 8. Note that the housing component member 8 can be made of a substance such as an insulator, and
Is fixed by the storage section constituent member 8, and the case 6b
May be configured to fix the storage section constituting member 8. Even in the case of such a structure of the motor control device, the power element 1 can be arranged below the printed circuit board 2 as in the case of the first and second embodiments. Can be reduced, and the size of the device can be reduced.

[0026]

According to the motor control device of the present invention, it is possible to dispose a power element on one surface of the heat sink in the storage portion formed by the substrate and the heat sink, so that the planar shape of the motor control device is reduced. The size can be reduced, the device can be reduced in size, and the mounting layout can be improved.

[0027] Further, the heat sink has a concave shape on one surface, and the recessed portion on one surface of the heat sink on which the power element is disposed and the back surface of the substrate constitute a housing portion, so that the surface area of the heat sink is reduced. Since sufficient heat dissipation can be ensured, there is no deterioration in heat dissipation, and there is no need to prepare another member for forming the power element storage section. Can be improved.

Further, in addition to the above effects, even when a printed circuit board is used as the substrate, the power element is arranged on the heat sink, so that the substrate is not damaged by heat generated by the power element.

[Brief description of the drawings]

FIG. 1 is a sectional configuration diagram of a motor control device according to a first embodiment of the present invention.

FIG. 2 is a sectional configuration diagram of a motor control device according to a second embodiment of the present invention.

FIG. 3 is a sectional configuration diagram of a motor control device according to a third embodiment of the present invention.

FIG. 4 is a cross-sectional configuration diagram of a conventional motor control device.

[Explanation of symbols]

1. Power element 1a. Terminal 2. Printed circuit board 2
a. Lead frame, 2b. Through hole 3, 3b,
3c. Heat sink 3a. Storage section, 4. Screw 5. Solder 6, 6a, 6b. Case 7. Cover 8. Storage section constituent member.

Claims (5)

[Claims] 1. A motor control device comprising: a substrate having a control circuit; a heat sink disposed on the back side of the substrate; and a power element for applying a voltage responsive to the control circuit to a motor. A motor control device, wherein a housing is formed and the power element is arranged on one surface of the heat sink in the housing. 2. A motor control device according to claim 1, wherein one surface of the heat sink has a shape having a recess, and a housing portion is formed by a recessed portion of the heat sink on which the power element is arranged and a substrate. . 3. A heat sink having a flat plate shape is fixed to a case for fixing the substrate at a predetermined distance from the substrate, and a power element is surrounded by one surface of the heat sink, the substrate and the inner surface of the case. The motor control device according to claim 1, wherein the motor control device is disposed in a closed storage portion. 4. A heat sink having a flat plate shape, fixed by a housing fixing member at a predetermined distance from a substrate, and a power element is provided on one surface of the heat sink and on the inner surfaces of the substrate and the housing fixing member. The motor control device according to claim 1, wherein the motor control device is disposed in a storage section surrounded by: 5. The motor control device according to claim 1, wherein the board is a printed board.