JP2005102370A - Self-cooling motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-cooling motor which can efficiently cool a stator, a rotor, and a wiring board where electronic parts are arranged. <P>SOLUTION: A stator 14 and a rotor 20 for a brushless DC motor are arranged within a cylindrical metallic frame 12, and the rotor 20 is provided with a self-cooling fan 24, and the internal perimeter of the frame 12 is provided with the first wiring board 40, the second wiring board 48 and the third wiring board 50, and each of these wiring boards 40, 48, and 50 is provided with a vent hole, and a heat-radiating mount 60 made of aluminum is attached to a six FETs 62-1, 62-2, 62-3, 62-4, 62-5, and 62-6 attached to the third wiring board 50. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a self-cooling motor having a self-cooling fan.

  2. Description of the Related Art Conventionally, in a circuit-integrated motor, a self-cooling motor has been proposed that solves an obstacle to high output due to heat generation of electronic components and can obtain a cooling effect on electronic components and windings (Patent Document 1). ).

In this self-cooling motor, an outer peripheral surface opening is arranged in a self-cooling fan arranged opposite to the top surface of the rotor frame, and an electronic component is placed on the flow path of the cooling air guided and discharged from the outer peripheral surface opening. The attached heat radiator is arranged.
JP2000-50575

  In the conventional self-cooling motor, it is possible to flow cooling air to the electronic component by the rotation of the self-cooling fan.

  However, since the electronic component and the heat sink to which the electronic component is attached are attached to the outside of the self-cooling motor, the outer shape of the motor becomes large, and the cooling air may not necessarily flow to the electronic component. There is a problem.

  The self-cooling motor has a structure in which a flow path is opened in a part of the frame to cool the stator and the rotor. Since the direction is completely different from that of the passage, there is a problem that the electronic components and the stator and rotor cannot be efficiently cooled.

  Therefore, in view of the above problems, the present invention provides a self-cooling motor that can efficiently cool a wiring board on which a stator, a rotor, and electronic components are arranged.

  The invention according to claim 1 is a self-cooling motor in which a rotor is rotatably disposed on an inner periphery of a ring-shaped stator, and a self-cooling fan is provided on the rotor. The stator, the rotor, and the self-cooling fan are arranged on the inner peripheral portion of the cylindrical frame, a wiring board having a drive circuit for driving the motor is arranged inside the frame, and The self-cooling motor is characterized in that a ventilation hole is provided between the wiring board and the inner periphery of the frame.

  According to a second aspect of the present invention, an aluminum ring-shaped heat dissipating part is provided at one end of the frame that is opened, and a heat dissipating attachment part is provided from the ring-shaped heat dissipating part toward the inner peripheral side. The self-cooling motor according to claim 1, wherein the attached electronic component is attached to the heat dissipation attachment portion.

  The invention according to claim 3 is characterized in that there are a plurality of the wiring boards, and the plurality of wiring boards are attached along the axial direction of the frame at a predetermined interval. It is a self-cooling motor.

  According to a fourth aspect of the present invention, vent holes are respectively opened in a pair of brackets for fixing a pair of bearing members that rotatably support a rotating shaft of the rotor, and the pair of brackets are attached to the frame. The self-cooling motor according to claim 1.

  According to a fifth aspect of the present invention, a vent is opened in each of a pair of brackets that fix a pair of bearing members that rotatably support a rotating shaft of the rotor, and the pair of brackets are attached to the frame. The self-cooling type according to claim 1, wherein the one bracket, the self-cooling fan, the rotor, the other bracket, and the wiring board are attached to the inner periphery of the frame in this order. It is a motor.

  The invention according to claim 6 is the self-cooling motor according to claim 1, wherein the self-cooling motor is a brushless DC motor.

  In the self-cooling motor according to claim 1, when the rotor of the self-cooling motor rotates, the self-cooling fan also rotates at the same time, and air flows in from one opening of the cylindrical frame. The inflowing air becomes cooling air, cools the rotor, the stator, and the wiring board, and is discharged from the other opening. Further, since a vent is provided between the wiring board and the inner periphery of the frame, the cooling air can pass through the vent.

  In this way, the stator, rotor, and wiring board can be cooled simultaneously by the self-cooling fan, and the flow path of the cooling air flows in one direction inside the cylindrical frame. Can be cooled.

  In the self-cooling motor according to claim 2, since the electronic component attached to the wiring board is also attached to the heat radiating attachment portion, the heat radiated from the electronic component is the aluminum heat radiating attachment portion and the ring shape. It is possible to dissipate heat from the heat dissipating part, and to efficiently dissipate the heat.

  In the self-cooling motor according to claim 3, since there are a plurality of wiring boards, and the plurality of wiring boards are attached along the axial direction of the frame with a predetermined interval, there are a plurality of wiring boards. Can also be cooled efficiently.

  In the self-cooling motor according to claim 4, since the ventilation holes are opened in the pair of brackets to which the rotor is attached, the cooling air can flow through the ventilation holes. It can be cooled efficiently.

  In the self-cooling motor of the invention according to claim 5, since it is attached to the inner periphery of the frame in the order of one bracket, the self-cooling fan, the rotor, the other bracket, and the wiring board, the self-cooling fan The raised cooling air can cool these components in turn.

  In the self-cooling motor according to the sixth aspect of the invention, since the self-cooling motor is a brushless DC motor, the components can be simply and easily arranged inside the frame.

  Hereinafter, a self-cooling motor 10 according to an embodiment of the present invention will be described with reference to FIGS.

(1) Structure of self-cooling motor 10 Self-cooling motor 10 of this embodiment is a brushless DC motor controlled by an inverter.

  The frame 12 of the self-cooling motor 10 is made of a metal cylindrical tube, and both ends thereof are open.

  In the longitudinal sectional view of FIG. 1, a ring-shaped stator 14 is attached to the right side on the inner peripheral side of the frame 12. As shown in FIG. 5, the stator 14 is obtained by winding a stator winding 18 around a stator core 16. An insulating layer is provided on the surface of the stator core 16.

  On the inner peripheral side of the stator 14, a rotor 20 made up of S-pole and N-pole permanent magnets is disposed. A rotating shaft 22 is provided at the center of the rotor 20, and a self-cooling fan 24 is attached to the right side of the rotor 20 in FIG. The self-cooling fan 24 is formed by integral molding with the rotor core 26 and a mold resin. The self-cooling fan 24 is arranged on the right side of the stator 14 in FIG.

  A bearing member 28 made of a bearing that supports the right side of the rotary shaft 22 is attached by a metal bracket 30. As shown in FIG. 8, the bracket 30 has a plurality of vent holes 32 opened concentrically. The bracket 30 is fitted and fixed to the inner peripheral portion of the right end portion of the frame 12.

  A bearing member 34 made of a bearing that rotatably supports the left side of the rotating shaft 22 is attached to a metal bracket 36 attached to a substantially central portion on the inner peripheral side of the cylindrical frame 12. The bracket 36 also has a vent hole 38 opened.

  A first wiring board 40 is provided between the bracket 36 and the stator 14. As shown in FIG. 4, the first wiring substrate 40 has both ends of a circular substrate cut away so that vent holes 42 are formed between the inner periphery of the frame 12. In addition, a through hole 44 is opened at the center of the first wiring board 40 so that the rotary shaft 22 penetrates. On the first wiring board 40, Hall ICs 46, 46, 46 for detecting the rotational position of the rotor 20 made of a permanent magnet are arranged at equal intervals every 120 °.

  A second wiring board 48 and a third wiring board 50 are attached to the left side of the bracket 36 at a predetermined interval along the axial direction of the frame 12. As shown in FIG. 3, the second wiring board 48 is provided with vent holes 52, 52 between the second wiring board 48 and the inner peripheral side of the frame 12. The third wiring board 50 is formed of a substantially triangular substrate as shown in FIG. 2 in order to provide the three vent holes 54, 54, 54. The second wiring board 48 and the third wiring board 50 are fixed by support pillars 56. The third wiring board 50 is fixed to the ring-shaped heat radiation part 58.

  The ring-shaped heat radiating portion 58 is made of aluminum so that heat can be easily radiated, and is fitted to the inner peripheral side of the left end portion of the cylindrical frame 12. The third heat dissipation substrate 50 is fixed to the right end of the ring-shaped heat dissipation portion 58. As shown in FIG. 7, a Y-shaped heat dissipating attachment portion 60 is stretched over the inner peripheral side of the ring-shaped heat dissipating portion 58 at the left end portion of the ring-shaped heat dissipating portion 58, that is, the left end portion of the frame 12. Is provided. The ring-shaped heat radiation part 58 and the heat radiation attachment part 60 are integrally formed by aluminum die casting.

  Electronic components constituting a drive circuit for driving the self-cooling motor 10 are arranged on the second wiring board 48 and the third wiring board 50, respectively. The FET 62 which is the six switching elements constituting the inverter circuit for allowing the drive current to flow through the stator winding 18 of the cold motor 10, that is, the brushless DC motor, is attached. Specifically, in the triangular third wiring board 50, as shown in FIG. 2, three sets of FETs 62-1 and 62-2, FETs 62-3 and 62-4, and FETs 62-5 and 62-6 are Y-shaped. Are arranged so as to face each other.

  When attention is paid to one set of FETs 62-1 and 62-2, the heat-dissipating attachment portion 60 is arranged between the set of FETs 62-1 and 62-2 as shown in FIG. The FETs 62-1 and 62-2 are fixed to the heat radiating attachment 60 with screws 63. As a result, the heat radiated from the six FETs 62-1, 62-2, 62-3, 62-4, 62-5, and 62-6 is radiated from the heat radiation mounting portion 60 and the ring-shaped heat radiation portion 58 made of aluminum. be able to.

  A connection line 19 extending from the stator winding 18 extends to and is connected to the third wiring board 50. The connector 64 extending from the three Hall ICs 46, 46, 46 is electrically connected to the second wiring board 48.

  On the third wiring board 50, lead wires 66 for supplying control signals and power from the outside are arranged between the heat radiating attachment portions 60.

(1) Operation State of Self-Cooling Motor 10 The operation state of the self-cooling motor 10 having the above configuration will be described.

  When the rotor 20 is rotated by a control signal from the outside, the self-cooling fan 24 is also rotated. When the self-cooling fan 24 rotates, air is sucked from the right side of the cylindrical frame 12 in FIG. In this case, since the vent hole 32 is opened in the bracket 30, the bracket 30 does not become an obstacle to suction (see FIG. 8). The cooling air, which is the air that has flowed into the frame 12, passes between the stator 18 and the rotor 20 (see FIG. 5), and then passes through two vent holes 42 of the first wiring board 40. (Refer to FIG. 4) Next, it passes through the vent hole 38 of the frame 36, then passes through two vent holes 52 of the second wiring board 48 (see FIG. 3), and then the third wiring board 50 It passes through the three vent holes 54 (see FIG. 2), then passes through the inner peripheral side of the ring-shaped heat radiating portion 58, and then passes between the Y-shaped heat radiating attachment portions 60 (see FIG. 7). 12 is discharged from the left end. In this case, in FIG. 1, the opening on the right side of the frame 12 is a suction port, and the opening on the left side is a discharge port.

  As described above, the stator 14, the rotor 20, the first wiring board 40, the second wiring board 48, and the third wiring board 50 are arranged in order inside the cylindrical frame 12, and these are the cooling air flowing inside the frame 12. Can be efficiently cooled.

  In addition, since the FETs 62-1, 62-2, 62-3, 62-4, 62-5, and 62-6 attached to the third wiring board 50 are attached to the heat radiation attachment portion 60 made of aluminum, It is possible to dissipate heat more efficiently by the heat dissipating action.

  When the rotation direction of the rotor 20 is reversed, the cooling air flow direction is reversed. In contrast to the above description, in FIG. 1, the left side of the frame 12 is a suction port and the right side is a discharge port.

  Further, since the flow rate of the cooling air can be adjusted by changing the shape of the self-cooling fan 24, the cooling characteristics can be easily changed.

  The self-cooling motor of the present invention can be variously modified without departing from the gist thereof.

  As the self-cooling motor of the present invention, it can be applied to motors for electric tools, motors for industrial equipment, motors for vehicles, etc., and motors for industrial equipment can be arranged inside a cylindrical frame so Can be applied to.

It is a longitudinal cross-sectional view of the self-cooling motor which shows one Embodiment of this invention. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. It is CC sectional view taken on the line in FIG. It is the DD sectional view taken on the line in FIG. It is a partial cutaway side view of the self-cooling motor of this embodiment. It is a left view of the self-cooling motor of this embodiment. Similarly, it is a right side view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Self-cooling motor 12 Frame 14 Stator 20 Rotor 22 Rotating shaft 24 Self-cooling fan 28 Bearing member 30 Bracket 32 Air vent 34 Bearing member 36 Bracket 38 Air vent 40 First wiring board 42 Air vent 44 Through port 46 Hall IC
48 2nd wiring board 50 3rd wiring board 52 Ventilation hole 54 Ventilation hole 56 Support pillar 58 Ring-shaped heat radiation part 60 Heat radiation attachment part 62 FET

Claims (6)

A rotor is rotatably arranged on the inner periphery of the ring-shaped stator,
In the self-cooling motor provided with a self-cooling fan in the rotor,
The stator, the rotor, and the self-cooling fan are arranged on the inner periphery of a metal cylindrical frame having both ends opened,
A self-cooling characterized in that a wiring board having a drive circuit for driving the motor is arranged inside the frame, and a vent is provided between the wiring board and the inner periphery of the frame. Motor. An aluminum ring-shaped heat dissipating part is provided at one end of the frame that is open,
A heat dissipating attachment part is provided from the ring-shaped heat dissipating part toward the inner peripheral side,
The self-cooling motor according to claim 1, wherein an electronic component attached to the wiring board is attached to the heat dissipation attachment portion. There are a plurality of the wiring boards,
The self-cooling motor according to claim 1, wherein the plurality of wiring boards are attached along the axial direction of the frame at a predetermined interval. A vent is opened in each of the pair of brackets that fix the pair of bearing members that rotatably support the rotation shaft of the rotor,
The self-cooling motor according to claim 1, wherein the pair of brackets are attached to the frame. A pair of brackets that fix a pair of bearing members that rotatably support the rotating shaft of the rotor are open to vent holes, and the pair of brackets are attached to the frame.
The self-cooling motor according to claim 1, wherein the one bracket, the self-cooling fan, the rotor, the other bracket, and the wiring board are attached to the inner periphery of the frame in this order. The self-cooling motor according to claim 1, wherein the self-cooling motor is a brushless DC motor.

Images