JP2000032729A - Brushless motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brushless motor capable of increasing the working efficiency of assembly work of a driving circuit. SOLUTION: This brushless motor 1 is provided with a plurality of switching elements 31 mounted on a heat sink 40 for heat cooling for switching the direction of current flowing through a coil 5 of a stator 6, a connecting terminal 31a of the switching element 31 inserted and fixed into the through hole of an electric circuit substrate 30 having a prescribed wiring pattern, and a driving circuit formed at the electric circuit substrate 30 for switching the direction of current flowing through the coil 5 to rotate a motor shaft 3. The heat sink 40, and a pressure part 50 pressing the switching element 31 to the heat sink 40 are fixed to the prescribed position on the electric circuit substrate 30. The switching element 31 is brought into pressure-contact with the heat sink 40 by the pressure part 50.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushless motor.

[0002]

2. Description of the Related Art A brushless motor includes a drive circuit for rotating a motor shaft by switching a current direction of a current flowing through a coil of a stator. This drive circuit generally includes an electric circuit having a predetermined wiring pattern. On the circuit board,
An electric circuit component such as a switching element for switching a current direction of a current flowing through the coil is mounted and formed, and housed in a circuit protection case of the brushless motor.

FIG. 8 is a sectional view showing a main part of a drive circuit of a conventional brushless motor, and FIG. 9 is a front view of the one shown in FIG. This brushless motor is of a three-phase two-pole winding type. As shown in FIGS. 8 and 9, six switching elements a having three connection terminals a1 dissipate heat generated by the switching elements a. It is mounted on an electric circuit board c with screws fixed to an aluminum heat sink b provided with heat dissipating fins b1.

[0004]

By the way, in order to assemble the drive circuit of the brushless motor, six switching elements a are fixed to the heat sink b with screws, and the connection terminals a1 of the respective switching elements a are connected to the electric circuit board c. The switching element a is mounted on the electric circuit board c, and the connection terminal a of the switching element a
1 is soldered to the electric circuit board c, and the electric circuit board c
The drive circuit is formed in the circuit protection case, and the drive circuit is housed in the circuit protection case, and the heat sink b is attached to the circuit protection case.

For this reason, in a conventional brushless motor,
The connection terminal a1 of the switching element a must support the weight of the heat sink b until the heat sink b is attached to the circuit protection case.
1 is formed on the connection terminal a1 of each switching element a by bending at the time of mounting to improve the bending resistance of the connection terminal a1. Therefore, in the conventional brushless motor, the forming process is necessary for the connection terminal a1 of the switching element a when assembling the drive circuit.

Moreover, in the conventional brushless motor, since the switching element a is screwed to the heat sink b, the six switching elements a must be individually attached to the heat sink b.

In addition, in the conventional brushless motor, when the switching element a is screwed to the heat sink b, a slight mounting error occurs between the switching elements a. Therefore, the six switching elements a fixed to the heat sink b Cannot be mounted on the electric circuit board c by an automatic machine, and is manually mounted on the electric circuit board c. Therefore, the conventional brushless motor has a problem that the assembling work of the drive circuit is troublesome and the working efficiency of the assembling work is poor.

Accordingly, an object of the present invention is to provide a brushless motor capable of improving the working efficiency of a driving circuit assembling operation.

[0009]

According to the present invention, a plurality of switching elements for switching a current direction of a current flowing through a coil of a stator are mounted on a heat sink for heat generation and cooling. The connection terminal of the switching element is inserted and fixed in a through hole of an electric circuit board provided with a predetermined wiring pattern, and the direction of the current flowing through the coil is switched on the electric circuit board to rotate the motor shaft. In a brushless motor in which a drive circuit is formed, a heat sink and a pressing component for pressing the switching element against the heat sink are fixed at predetermined positions on the electric circuit board, and the switching element is pressed against the heat sink by the pressing component. , Is adopted.

Therefore, according to the first aspect of the present invention, after inserting the connection terminal of the switching element into the through hole of the electric circuit board and mounting the plurality of switching elements individually on the electric circuit board, The heat sink and the pressing component are fixed at the position, the switching element is pressed against the heat sink with the pressing component, the connection terminal of the switching element is fixed to the electric circuit board, and the drive circuit can be formed on the electric circuit board. .

Further, in the first aspect of the present invention, since the heat sink is fixed to the electric circuit board, the weight of the heat sink is supported by the electric circuit board. Therefore, it is necessary to support the weight of the heat sink by the connection terminals of the switching elements. In addition, it is not necessary to form the connection terminal of the switching element by bending at the time of mounting to improve the bending resistance of the connection terminal.

According to the first aspect of the present invention, since the switching element is pressed against the heat sink by the pressing component, it is possible to attach a plurality of switching elements to the heat sink at once by the pressing component.

According to a second aspect of the present invention, there is provided the brushless motor according to the first aspect, wherein the pressing component is made of an elastic metal, and a fixing member fixed to the electric circuit board and an erecting member from the fixing member. A first elastic piece that comes into contact with the switching element and presses the switching element toward the heat sink, and a second elastic piece that rises from the fixing member and abuts on the heat sink to press the heat sink toward the switching element; The switching element and the heat sink are sandwiched between the first and second elastic pieces.

According to the second aspect of the present invention, the switching element mounted on the electric circuit board and the heat sink mounted on the electric circuit board are connected to the first and second pressing parts.
In a state where the switching element is securely pressed against the heat sink, the heat sink and the connection terminal of the switching element can be fixed to the electric circuit board.

According to a third aspect of the present invention, in the brushless motor according to the second aspect, the fixing member is sandwiched between the electric circuit board and the heat sink, and the heat sink is fixed by a fastening member fixing the heat sink to the electric circuit board. And being fixed to an electric circuit board.

Therefore, according to the third aspect of the invention, the fixing of the heat sink to the electric circuit board and the fixing of the fixing member of the pressing component to the electric circuit board can be completed at once by the same fastening member.

According to a fourth aspect of the present invention, in the brushless motor according to the third aspect, the heat sink has conductivity and is located at a contact position where the heat sink contacts at least one of the fixing member and the heat sink on the electric circuit board. A land connected to the ground wiring provided on the electric circuit board is formed, and the land is electrically connected to the pressing component and the heat sink fixed to the electric circuit board. Things.

Therefore, in the invention of claim 4, the static electricity charged on at least one of the pressing component and the heat sink flows from the land of the electric circuit board to the ground wiring and is grounded.

Further, according to the fourth aspect of the present invention, since the land is formed at the contact position of at least one of the fixing member and the heat sink on the electric circuit board, the fixing member of the pressing component and the fastening member between the heat sink are formed. The fixing to the electric circuit board and the electrical connection between the pressing component and the heat sink and the land are simultaneously performed, so that the pressing component and the heat sink can be connected to the ground wiring.

According to a fifth aspect of the present invention, there is provided the brushless motor according to any one of the first to fourth aspects, wherein a positioning projection is formed on the pressing component, and the positioning projection is provided on a predetermined portion of the electric circuit board. It is inserted into a projection insertion hole provided at a position.

According to the fifth aspect of the present invention, the pressing component is disposed at a predetermined position on the electric circuit board and fixed by inserting the positioning projection of the pressing component into the projection insertion hole of the electric circuit board. Can be.

According to a sixth aspect of the present invention, in the brushless motor according to any one of the first to fifth aspects, a positioning pin is provided on the heat sink, and the positioning pin is provided at a predetermined position on the electric circuit board. Characterized in that it is inserted into the pin insertion hole provided.

According to the sixth aspect of the present invention, the heat sink can be arranged and fixed at a predetermined position on the electric circuit board by inserting the positioning pins of the heat sink into the pin insertion holes of the electric circuit board.

[0024]

According to the first aspect of the present invention, the connection terminal of the switching element is inserted into the through hole of the electric circuit board,
After the switching elements are individually mounted on the electric circuit board, the heat sink and the pressing component are fixed at predetermined positions on the electric circuit board, and the switching element is pressed against the heat sink with the pressing component, and the connection terminals of the switching element are connected to the electric circuit. Since the drive circuit can be formed on the electric circuit board by being fixed to the substrate, the switching element can be mounted on the electric circuit board by an automatic machine, and therefore, the switching element can be mounted on the electric circuit board. As compared with the conventional products shown in FIGS. 8 and 9 which have to rely on humans, the operation efficiency of the drive circuit assembling operation can be improved.

Further, according to the first aspect of the present invention, since the weight of the heat sink is supported by the electric circuit board,
There is no need to support the weight of the heat sink with the connection terminals of the switching element, and it is not necessary to form the connection terminal of the switching element by bending at the time of mounting to improve the bending resistance performance of the connection terminal. As compared with the conventional products shown in FIGS. 8 and 9 that require the forming process, the operation efficiency of the drive circuit assembling operation can be improved.

In addition, according to the first aspect of the present invention, since the switching element is pressed against the heat sink by the pressing component, it is possible to attach a plurality of switching elements to the heat sink at a stroke by the pressing component. As compared with the conventional products shown in FIGS. 8 and 9 in which the switching elements have to be individually attached to the heat sink, the operation efficiency of the drive circuit assembling operation can be improved.

According to the second aspect of the present invention, the switching element mounted on the electric circuit board and the heat sink mounted on the electric circuit board are sandwiched between the first and second elastic pieces of the pressing component, and the switching element is mounted on the heat sink. Since the heat sink and the connection terminal of the switching element can be fixed to the electric circuit board in a state where the switching element is securely pressed, the pressing element can reliably press the switching element against the heat sink.

According to the third aspect of the present invention, the fixing of the heat sink to the electric circuit board and the fixing of the fixing member of the pressing component to the electric circuit board can be completed at once by the same fastening member. The working efficiency of fixing the pressing component to the electric circuit board is improved.

According to the fourth aspect of the present invention, the static electricity charged on at least one of the pressing component and the heat sink flows from the land of the electric circuit board to the ground wiring and is grounded.
The switching element can be protected from the static electricity.

Further, according to the present invention, the fixing of the pressing component to the electric circuit board by the fastening member of the fixing member and the heat sink and the electrical connection of the pressing component and the heat sink to the land are simultaneously performed. Since the pressing component and the heat sink can be connected to the ground wiring, the work efficiency of connecting the pressing component and the heat sink to the ground wiring is improved.

According to the fifth aspect of the present invention, since the positioning projection of the pressing component is inserted into the projection insertion hole of the electric circuit board, the pressing component can be arranged and fixed at a predetermined position on the electric circuit board. The arrangement of the pressing component at a predetermined position on the electric circuit board and the fixing of the pressing component at the predetermined position on the electric circuit substrate are facilitated.

According to the sixth aspect of the present invention, the heat sink can be arranged and fixed at a predetermined position on the electric circuit board by inserting the positioning pins of the heat sink into the pin insertion holes of the electric circuit board. This facilitates the disposition of the heat sink at the predetermined position and the fixing of the heat sink at the predetermined position of the electric circuit board.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a cutaway sectional view showing an example of an embodiment in which each of the first to sixth aspects of the present invention is implemented. The brassless motor 1 is used as a blower fan motor of a vehicle air conditioner, is a three-phase two-pole winding type, and rotatably supports a motor shaft 3 via a bearing 2. Coil 5 in housing 4
Is provided, and a ferrite magnet 7 disposed close to the stator 6 is fixed to the motor shaft 3 via a yoke 8.

A sirocco fan 10 for blowing air is attached to the tip of the motor shaft 3.
At the rear end, a sensor magnet 11 indicating the rotational position of the ferrite magnet 7 is attached. Flange portion 4a provided at the rear end of motor shaft 3 of housing 4
, A circuit protection case 20 made of synthetic resin is mounted with a ring-shaped mounting bracket 12 and an anti-vibration rubber 13 interposed therebetween.

The circuit protection case 20 is composed of an upper case 21 located on the front end side of the motor shaft 3 and a lower case 22 located on the rear end side of the motor shaft 3.
A drive circuit for rotating the motor shaft 3 by switching the direction of the current flowing through the coil 5 of the stator 6 is housed in the circuit protection case 20.

The driving circuit includes a switching element 31 for switching a current direction of a current flowing through the coil 5 of the stator 6 on an electric circuit board 30 having a predetermined wiring pattern.
Also, it is formed by mounting electric circuit components such as the electrolytic capacitor 32. The electric circuit board 30 has a component surface 30a on which the electric circuit components are mounted facing upward in the drawing,
Boss portion 2 suspended from top wall 21a of upper case 21
3 and is arranged orthogonally to the motor shaft 3.

A metal joint bar 33 penetrating the electric circuit board 30 is provided on the component surface 30a of the electric circuit board 30.
Has been implemented. The joint bar 33 is electrically connected to the drive circuit, and is also electrically connected to the coil 5 of the stator 6 via a metal bus bar 34 and terminal pins 35.

On the component surface 30 a of the electric circuit board 30, a metal pressing component 50 for pressing the switching element 31 against the heat sink 40, and an aluminum heat sink 40 to which the switching element 31 is pressed by the pressing component 50. Are fixed by screws 36 which are fastening members.

The heat sink 40 includes the switching element 3
1 and the switching element 31
And a radiating portion 43 provided with radiating fins 42 for radiating heat generated by the radiating fins 42. The leg portions 41 are fixed with screws to the electric circuit board 30, and the radiating portions 43 supported by the leg portions 41 are
Is exposed to the outside of the circuit protection case 20 and the upper case 2
It is attached to one top wall 21a.

The leg portion 41 of the heat sink 40 has a wedge-shaped cross section in which the cross-sectional shape of the press-contact portion where the switching element 31 is pressed is gradually tapered from the heat radiating portion 43 side of the heat sink 40 to the bottom surface side of the leg portion 42. It is shaped.

In this brushless motor 1, the MO
An S-type field effect transistor is used as the switching element 31. The switching element 31 includes three connection terminals 31a, which are inserted into through holes of the electric circuit board 30 and fixed by soldering. I have.

FIG. 2 is a front view showing a main part of the drive circuit shown in FIG. 1, and FIG. 3 is a sectional view taken along line X--X in FIG.
It is a line sectional view. As shown in FIG. 2, in the brushless motor 1, six switching elements 31 are used to appropriately switch the direction of the current flowing through the coil 5 of the stator 6, and the six switching elements 31 are arranged in a line. And mounted on the electric circuit board 30, and the heat sink 40
Are disposed along the switching element 31.

In FIG. 2, reference numeral 51 denotes a first elastic piece of the pressing component 50, and reference numeral 53 denotes a pressing component 50.
Reference numeral 57 denotes a positioning projection of the pressing component 50. The pressing component 50 will be described later in detail.

As shown in FIG. 2 and FIG.
Reference numeral 0 denotes a bottom surface at both ends of the leg portion 41 in the direction along the switching element 31, a positioning pin 44 is protruded, and a screw hole 45 for a screw 36 is formed.

The fixing member 53 of the pressing component 50 has a pin hole 54 through which the positioning pin 44 of the heat sink 40 is inserted.
And a screw hole 55 for a screw 36 is formed at a position corresponding to the screw hole 45 of the heat sink 40 with the positioning pin 44 of the heat sink 40 inserted into the pin hole 54.

A heat sink 40 is provided on the electric circuit board 30.
A pin insertion hole 61 into which the positioning pin 44 is inserted is formed. Further, the electric circuit board 30 is provided with a screw insertion hole 62 for the screw 36 at a position corresponding to the screw hole 45 of the heat sink 40 with the positioning pin 44 of the heat sink 40 inserted into the pin insertion hole 61. Land 6
3 are also formed. The land 63 is connected to a ground wire provided on the electric circuit board 30, and the ground wire is connected to a GN provided on the electric circuit board 30.
It is electrically connected to D (ground).

The fixing member 53 of the pressing component 50 has its pin hole 54 aligned with the pin insertion hole 61 of the electric circuit board 30, and the screw hole 55 aligned with the screw insertion hole 62 of the electric circuit board 30. It is arranged on the component surface 30 a of the board 30 and contacts the lands 63 of the electric circuit board 30.

The heat sink 40 allows the positioning pins 44 to be inserted into the pin holes 54 of the pressing component 50 and the pin insertion holes 61 of the electric circuit board 30, and to the screw holes 55 of the pressing component 50 and the screw insertion holes 62 of the electric circuit board 30. The screw holes 45 are aligned with each other and are disposed on the fixing member 53 of the pressing component 50.

The heat sink 40 is connected to the component surface 30.
a screw insertion hole 62 of the electric circuit board 30 and the pressing component 50 from the solder surface 30b side of the electric circuit board 30 opposite to
The screw 36 is fixed to the electric circuit board 30 by a screw 36 that passes through the screw hole 55 and reaches the screw hole 45.

The pressing member 50 has its fixing member 53 sandwiched between the heat sink 40 and the electric circuit board 30.
Screw 36 and heat sink 40 together with electric circuit board 3
It is fixed to 0, is brought into contact with the land 63 of the electric circuit board 30, and is electrically connected to the ground wiring of the electric circuit board 30 via the land 63 together with the heat sink 40.

FIG. 4 is a plan view showing the pressing part in FIG. 1, FIG. 5 is a rear view of the one shown in FIG.
FIG. 6 is a sectional view taken along line YY of FIG. As shown in FIGS. 1 to 6, the pressing component 50 is made of a metal having elasticity, and has a thin plate-shaped fixing member 53 that is disposed on the component surface 30 a of the electric circuit board 30 and fixed to the electric circuit board 30. Have. The fixing member 53 has six element insertion holes 56 for inserting the switching elements 31 mounted on the electric circuit board 30 at predetermined intervals along the longitudinal direction of the fixing member 53.

From one end of the fixing member 53 sandwiching each of the element insertion holes 56, first elastic pieces 51 that abut against the switching element 31 and press the switching element 31 toward the heat sink 40 stand up. From the other end of the fixing member 53 sandwiching each of the element insertion holes 56, second elastic pieces 52 that abut against the leg 41 of the heat sink 40 and press the leg 41 toward the switching element 31 stand upright. The first and second elastic pieces 51 and 52 are arranged to face each other with the element insertion holes 56 interposed therebetween.

The first elastic piece 51 includes an upright portion 51a that rises from the fixing member 53 of the pressing component 50, and the upright portion 5a.
And a pressing portion 51b that extends upward from the tip of 1a toward the inside of the fixing member 53 and curves in a downwardly convex shape.

The second elastic piece 52 includes an upright portion 52a that rises from the fixing member 53 of the pressing component 50, and the upright portion 5a.
A pressing portion 52b extending upward from the tip of 2a toward the inside of the fixing member 53 and bending downwardly;
b, and a return portion 52c protruding upward and outward of the fixing member 53 from the front end of the fixing member 53.

At both ends in the longitudinal direction of the fixing member 53, a screw hole 55 for the screw 36 and a pin hole 54 for inserting the positioning pin 44 of the heat sink 40 are formed, respectively. At the center portion of the fixing member 53, four positioning projections 57 projecting in opposite directions to the first and second elastic pieces 51 and 52 are arranged at two ends in the width direction so as to face each other. Is formed.

The electric circuit board 30 has a projection insertion hole 64 for the positioning projection 57 (see FIG. 7). When the positioning projection 57 of the pressing component 50 is inserted into the projection insertion hole 64, each element insertion hole 56 of the pressing component 50 is formed in the electric circuit board 30. The mounted switching element 31 is appropriately inserted, and the pin hole 54 of the pressing component 50 matches the pin insertion hole 61 of the electric circuit board 30, and the screw hole 55 of the pressing component 50 fits the screw insertion hole 62 of the electric circuit board 30. Is set at a predetermined position that matches

FIGS. 7A and 7B are explanatory views showing attachment of the switching element to the heat sink, wherein FIG. 7A shows a state before attachment to the heat sink, and FIG. 7B shows a state after attachment to the heat sink. The switching element 31 is connected to the heat sink 40
First, the electric circuit board 30
The connection terminal 31a of the switching element 31 is inserted into the through hole of the electric circuit board 30 from the component surface 30a side of
The switching element 31 is mounted on the electric circuit board 30.

Next, the switching element 31 is inserted into the element insertion hole 56 of the pressing component 50, and the positioning projection 57 of the pressing component 50 is inserted into the projection insertion hole 64 of the electric circuit board 30. The pressing component 50 is placed at a predetermined position on the component surface 30a.

At this time, the pressing component 50 is
4 corresponds to the pin insertion hole 61 of the electric circuit board 30, and the screw hole 55 matches the screw insertion hole 62 of the electric circuit board 30. At this time, the first elastic piece 5 of the pressing component 50
1 contacts the switching element 31 and is displaced outward from the fixed member 53 from the initial position, and presses the switching element 31 inwardly of the fixed member 53 by a repulsive force resulting from the displacement.

Thereafter, the leg 41 of the heat sink 40 is inserted between the switching element 31 and the second elastic piece 52 of the pressing component 50, and the positioning pin 44 projecting from the bottom surface of the leg 41 is The heat sink 40 is placed at a predetermined position on the fixing member 53 of the pressing component 50 by inserting the heat sink 40 into the pin hole 54 of the pressing component 50 and the pin insertion hole 61 of the electric circuit board 30.

The second elastic piece 52 of the pressing part 50
Is formed at its tip with a return portion 52c protruding outward and upward of the fixing member 53. Moreover, the leg portion 42 of the heat sink 40 has a wedge-shaped cross-sectional shape in which the cross-sectional shape of the press-contact portion where the switching element 31 is pressed is gradually tapered from the heat-radiating portion 43 side of the heat sink 40 toward the bottom surface side of the leg portion 42. It has been. For this reason, in the brushless motor 1, the leg 41 of the heat sink 40 can be easily inserted between the switching element 31 and the second elastic piece 52 of the pressing component 50.

The positioning pins 44 of the heat sink 40 are inserted into the pin holes 54 of the pressing component 50 and the pin insertion holes 61 of the electric circuit board 30, and the heat sink 40 is inserted into the pressing component 50.
When the heat sink 40 is placed at a predetermined position on the fixing member 53, the screw hole 45 of the heat sink 40
And the screw insertion hole 62 of the electric circuit board 30.

Then, the second elastic piece 52 of the pressing part 50
Abuts against the leg portion 41 of the heat sink 40 and is displaced outward from the fixing member 53 from the initial position, and presses the leg portion 41 of the heat sink 40 inwardly of the fixing member 53 by a repelling force resulting from the displacement. Then, the switching element 31 is reliably pressed against the leg 41 of the heat sink 40 in cooperation with the first elastic piece 51 of the pressing component 50.

Finally, the solder surface 30 of the electric circuit board 30
The screw 36 is inserted into the screw insertion hole of the electric circuit board 30 and the screw hole 56 of the pressing component 50 from the
0 is fixed to the electric circuit board 30 with screws, the fixing member 53 of the pressing component 50 is fixedly fastened to the electric circuit board 30 together, and the heat sink 40 and the pressing component 50 are fixed to the electric circuit board 30, and the switching element 31 is connected. The terminal 31a is soldered to the electric circuit board 30.

By the way, in the conventional product shown in FIGS. 8 and 9,
After the six switching elements a are screwed to the heat sink b, the six switching elements a are connected to the electric circuit board c.
Mounting, a mounting error occurs between the switching elements a mounted on the heat sink b, and the automatic device cannot be used to mount the switching element a on the electric circuit board c. I was relying on.

On the other hand, in the brushless motor 1, 6
After individually mounting the switching elements 31 on the electric circuit board 30, the heat sink 40 and the pressing component 50 are fixed at predetermined positions on the electric circuit board 30, and the switching element 31 is pressed against the heat sink 40 with the pressing component 50. By connecting the switching element 31 to the heat sink 40 and fixing the connection terminals 31 a of the switching element 31 to the electric circuit board 30, a drive circuit can be formed on the electric circuit board 30.

Accordingly, in the brushless motor 1, an automatic machine can be used for mounting the switching element 31 on the electric circuit board 30, and the mounting has to be manually performed. In comparison with the above, the operation efficiency of the drive circuit assembling operation can be improved.

In the conventional products shown in FIGS. 8 and 9, since the weight of the heat sink b is supported by the connection terminal a1 of the switching element a until the heat sink b is attached to the circuit protection case, the connection terminal a1 of the switching element a is bent. A forming process for improving the bending resistance of the connection terminal a1 is required for the connection terminal a1 of each switching element a.

On the other hand, in the brushless motor 1, the heat sink 40 is fixed to the electric circuit board 30 and the weight of the heat sink 40 is supported by the electric circuit board 30.
There is no need to support the weight of the heat sink 40 with the connection terminal 31a of the switching element 31, and each switching element 3
The forming process for the one connection terminal 31a is unnecessary. Accordingly, in the brushless motor 1, the work efficiency of the assembling work of the drive circuit can be improved as compared with the conventional products shown in FIGS.

Further, in the conventional products shown in FIGS. 8 and 9, the six switching elements a are individually screwed to the heat sink b to attach the switching elements a to the heat sink b. On the other hand, in the brushless motor 1, the mounting of the six switching elements 31 to the heat sink 40 can be performed at a stroke by the pressing component 50. In this respect, the driving circuit is also different from the conventional circuit shown in FIGS. The work efficiency of the assembling work can be improved.

The pressing component 50 includes a first elastic piece 51 which contacts the switching element 31 and presses the switching element 31 toward the heat sink 40;
0 and the heat sink 40 is switched to the switching element 31.
The switching element 31 and the heat sink 40 are sandwiched between the first and second elastic pieces 51 and 52.

For this reason, in the brushless motor 1, the switching element 31 mounted on the electric circuit board 30 and the heat sink 40 are sandwiched between the first and second elastic pieces 51 and 52 of the pressing component 50, and are attached to the heat sink 40. In a state where the switching element 31 is securely pressed, the heat sink 40 and the switching element 31 are connected to the electric circuit board 30.
Therefore, the pressing element 50 can reliably press the switching element 31 against the heat sink 40.

In the brushless motor 1, the fixing member 53 of the pressing component 50 is sandwiched between the heat sink 40 and the electric circuit board 30, and the heat sink 40 is connected to the electric circuit board 3.
Since the fixing member 53 of the pressing component 50 is fixedly fastened to the electric circuit board 30 by the screw 36 fixed to 0, the fixing of the heat sink 40 and the pressing component 50 to the electric circuit board 30 is completed at once by the same screw 36. The work efficiency of the work of fixing the heat sink 40 and the pressing component 50 to the electric circuit board 30 is improved.

In the brushless motor 1, a land 63 having a screw insertion hole 62 for the screw 36 is formed on the electric circuit board 30, as shown in FIG.
Is connected to the ground wiring of the electric circuit board 30 and is electrically connected to the metal pressing component 50 and the heat sink 40. From the ground wiring to ground, and the switching element 31 can be protected from the static electricity.

Further, in the brushless motor 1, the screw 36 between the fixing member 53 of the pressing part 50 and the heat sink 40 is provided.
To the electric circuit board 30 and the electrical connection between the pressing component 50 and the heat sink 40 and the land 63 at the same time to connect the pressing component 50 and the heat sink 40 to the ground wiring of the electric circuit substrate 30. As a result, the work efficiency of the connection work between the pressing component 50 and the heat sink 40 and the ground wiring is improved.

In the brushless motor 1, as shown in FIG. 7, the pressing component 50 is inserted into the projection insertion hole 64 of the electric circuit board 30 by inserting the positioning projection 57 of the pressing component 50 into the electric circuit board 30. Can be arranged and fixed at the predetermined position of the electric circuit board 30, and it is easy to arrange the pressing component 50 at the predetermined position of the electric circuit board 30 and to fix the pressing component 50 at the predetermined position of the electric circuit board 30.

Further, in the brushless motor 1, the positioning pin 44 of the heat sink 40 is
4 and the pin insertion holes 61 of the electric circuit board 30, the heat sink 40 can be arranged and fixed at predetermined positions on the pressing parts 50 and the electric circuit board 30. And the fixing of the heat sink 40 at the predetermined positions of the pressing component 50 and the electric circuit board 30 becomes easy.

[Brief description of the drawings]

FIG. 1 is a cutaway sectional view showing an example of an embodiment in which the inventions of claims 1 to 6 are implemented together.

FIG. 2 is a front view showing a main part of a drive circuit of the one shown in FIG.

FIG. 3 is a sectional view taken along line XX of FIG.

FIG. 4 is a plan view showing a pressing component in FIG. 1;

FIG. 5 is a rear view of the one shown in FIG. 4;

FIG. 6 is a sectional view taken along line YY of FIG.

FIGS. 7A and 7B are explanatory views showing attachment of the switching element to the heat sink, wherein FIG. 7A shows a state before attachment to the heat sink and FIG. 7B shows a state after attachment to the heat sink.

FIG. 8 is a cross-sectional view showing a main part of a conventional drive circuit.

FIG. 9 is a front view of what is shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 brushless motor 3 motor shaft 5 coil 6 stator 30 electric circuit board 31 switching element 31a connection terminal 36 screw (fastening member) 40 heat sink 44 positioning pin 50 pressing component 51 first elastic piece 52 second elastic piece 53 fixing member 57 positioning protrusion Part 61 Pin insertion hole 63 Land 64 Projection insertion hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Adult Sano 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonic Corporation F-term (reference) 5H019 AA00 AA10 BB01 BB05 BB19 BB22 CC04 DD01 EE00 EE09 FF00 FF01

Claims (6)

[Claims] A plurality of switching elements (31) for switching a current direction of a current flowing through a coil (5) of a stator (6) are mounted on a heat sink (40) for heat generation and cooling, and provided with a predetermined wiring pattern. Circuit board (3
The connection terminal (31a) of the switching element (30) is inserted and fixed in the through hole of (0), and the current direction of the current flowing through the coil (5) is switched to the electric circuit board (30) to change the motor shaft. A brushless motor provided with a drive circuit for rotating (3), wherein a heat sink (40) and a pressing component for pressing the switching element (31) against the heat sink (40) are provided at predetermined positions on the electric circuit board (30). (50) and the switching element (3) by the pressing part (50).
A brushless motor characterized in that 1) is pressed against a heat sink (40). 2. The brushless motor according to claim 1, wherein the pressing component is made of a metal having elasticity.
A fixing member (5) fixed to the electric circuit board (30)
3) and a first elastic piece (5) that rises from the fixing member (53), contacts the switching element (31), and presses the switching element (31) toward the heat sink (40).
1) and a second elastic piece (52) that rises from the fixing member (53), abuts against the heat sink (40), and presses the heat sink (40) toward the switching (31) element side. A brushless motor characterized in that the switching element (31) and the heat sink (40) are sandwiched between the two elastic pieces (51, 52). 3. The brushless motor according to claim 2, wherein said fixing member (53) is provided on said electric circuit board (3).
0) and the heat sink (40), and are fixed to the electric circuit board (30) together with the heat sink (40) by a fastening member (36) for fixing the heat sink (40) to the electric circuit board (30). A brushless motor. 4. The brushless motor according to claim 3, wherein the heat sink (40) has conductivity, and at least one of the fixing member (53) and the heat sink (40) on the electric circuit board (30). A land (63) connected to a ground wire provided on the electric circuit board (30) is formed at a contact position where the land (63) is in contact with the electric circuit board (30), and the land (63) is fixed to the electric circuit board (30). A brushless motor electrically connected to the pressing component (50) and the heat sink (40). 5. The brushless motor according to claim 1, wherein a positioning projection (57) is formed on said pressing component (50), and said positioning projection (57) is provided on said electric part. A brushless motor, wherein the brushless motor is inserted into a protrusion insertion hole (64) provided at a predetermined position of a circuit board (30). 6. The brushless motor according to claim 1, wherein a positioning pin (44) is protruded from said heat sink (40), and said positioning pin (44).
Is inserted into a pin insertion hole (61) provided at a predetermined position of the electric circuit board (30).