JP6647152B2 - DC brushless motor and ventilation blower - Google Patents

Description

  The present invention relates to a DC brushless motor for a ventilation blower having a built-in substrate and a ventilation blower.

  In the structure of a direct current (DC) brushless motor as an electric motor, a rotor is arranged in a case cover in which a stator around which a coil is wound is fitted. Then, the control circuit board provided with the shaft through-hole is fixed to the stator, and the case is attached. Further, the DC brushless motor is equipped with a drive circuit for generating a current for rotating the rotor, and a microcomputer for controlling the drive circuit.

  The DC brushless motor having a built-in drive circuit and control circuit board has been applied to various products in a variety of product fields, mainly due to a growing demand for energy saving and product miniaturization. In this trend, demands for DC brushless motors having a built-in drive circuit and control circuit board are increasing even in systems for consumer use such as ventilation blowers, which have not conventionally been applied in a very large scale and range.

  When considering the application of DC brushless motors to consumer systems, the obstacles in many cases are that DC merit, such as energy saving and miniaturization, cannot be justified by the cost increase from AC motors. It is a point that is determined. In order to remove the obstacles, various techniques have been disclosed which aim at reducing material costs and manufacturing costs and improving added value.

  For example, Patent Document 1 discloses the following DC brushless motor technology. Attach the cylindrical resin bracket to the cylindrical metal stator frame. The resin bracket has a through hole through which an output pin connected to the winding of the stator is inserted. This through-hole is closed by a moisture-proof seal. A bearing holding portion is provided on the load side of the resin bracket to hold the rotor. On the other hand, a circuit board on which electronic components are mounted is housed on the non-load side, and the electronic components are conductively connected to the inserted pins. In addition, the inside of the upper surface of the metal motor cover radiates heat by being in contact with the electronic components and closes the opening of the stator frame. With the above configuration, productivity is improved while ensuring heat dissipation and moisture resistance, and cost is reduced.

Japanese Patent No. 5268845

  According to the technology of Patent Document 1, heat is radiated by a simple structure in which an electronic component and a motor cover are brought into contact with each other, and a sealing material is applied only to a through-hole of an output pin conductively connected to a winding. Since moisture resistance can be secured, cost reduction and improvement in productivity are realized. However, since the heat radiating means relies only on heat conduction from the electronic components to the motor cover, the heat radiating performance may be insufficient in a high-output DC brushless motor. Furthermore, if the distance between the heat-generating component to be radiated and the inside of the upper surface of the motor cover is large and there are high-profile components other than the heat-generating component, it is necessary to add drawing work to connect the motor cover to the heat-generating component. Causes deterioration. In addition, since the shape of the cover cannot be shared with the cover for the AC motor, there is a concern about the burden of the cost for creating a new mold.

  As described above, regarding the heat radiation of the DC brushless motor, the heat radiation means which requires the manufacturing cost such as the application of the potting material, the integral molding of the board case and the heat radiation plate, and the drawing process addition of the metal cover for the heat radiation is not used. There is also a demand for a configuration that pursues cost reduction by excluding functions other than the minimum required.

  The present invention has been made in view of the above, and an object of the present invention is to provide a DC brushless motor that secures necessary heat radiation performance even when used at high output.

In order to solve the above-described problems and achieve the object, the present invention provides a tubular frame made of a heat conductive material, a stator mounted in a body of the tubular frame and provided with a coil, and a rotating shaft. A plurality of electronic components including a heat-generating component mounted thereon , a circuit board connected to a coil of a stator, a first region in contact with the heat-generating component, and a contact with the circuit board. A heat sink having a first region and a second region different from the first region, a heat dissipation sheet having one surface in contact with the heat sink and the other surface in contact with the heat-generating component and the circuit board, and a thermal contact with the heat sink. a thermally conductive material for closing the first opening of Rutotomoni tubular frame mode - and Takaba, one end in contact with the heat sink, the third territories which the other end is mounted heat generating component on the circuit board And has a board connecting terminal to be contacted by the fourth region is different from the fifth region corresponding to the second region, the heat radiation sheet is interposed between the heat generating component and the first region of the heat sink And being interposed between the second region of the heat sink and the fourth region of the circuit board .

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that a DC brushless motor which ensures the required heat dissipation performance even when used at high output can be obtained.

Partial sectional view of the DC brushless motor according to the first embodiment. A part enlarged view of FIG. Top view of a circuit board in a state where a heat sink is connected in the DC brushless motor according to the first embodiment. Main part enlarged view of a modified example of the DC brushless motor of the first embodiment. Partial sectional view of a DC brushless motor according to a second embodiment. Top view of a circuit board in a state where a heat sink is connected in the DC brushless motor according to the second embodiment. Partial sectional view of a DC brushless motor according to a third embodiment. Top view of the intermediate layer of the multilayer substrate in FIG. Top view of the intermediate layer of the multilayer substrate in FIG. Partial sectional view of a DC brushless motor according to a fourth embodiment. Enlarged view of part B in FIG. Top view of a circuit board to which a heat sink according to a fourth embodiment is connected. Sectional view of a ventilation fan equipped with a DC brushless motor according to a fifth embodiment of the present invention.

  Hereinafter, embodiments of a DC brushless motor and a ventilation blower according to the present invention will be described in detail with reference to the drawings. It should be noted that the present invention is not limited by the embodiment, and can be appropriately changed without departing from the gist of the present invention. Further, in the drawings described below, the scale of each member may be different from the actual scale for easy understanding. The same applies to each drawing. Further, hatching may not be used even in a cross-sectional view so as to make the drawings easy to see.

Embodiment 1 FIG.
FIG. 1 is a partial cross-sectional view of a DC brushless motor 201 according to Embodiment 1 of the present invention. First, the overall configuration of the DC brushless motor 201 will be described with reference to FIG.

  The DC brushless motor 201 according to the first embodiment includes a metal tubular frame 1 made of a heat conductive material, a stator 2 mounted in the body of the tubular frame 1 and provided with a coil 2a, and a vertical stand. And an output pin 5 connected to an end of the coil 2a, a rotor 6 rotatably arranged about a rotation axis, and a circuit in which an electronic component 101 constituting a drive circuit is mounted and connected to the output pin 5. A heat sink 9 in thermal contact with the substrate 8, an electronic component, and a motor cover 12 made of a heat conductive material which is in thermal contact with the heat sink 9 and closes the opening 1o of the cylindrical frame 1. And The heat sink 9 includes a board connection terminal 9a that is thermally connected to the circuit board 8.

  Further, it has an insulator 3 on the load side for insulating and protecting the coil 2a, and an insulator 4 on the opposite side to the load similarly. The heat sink 9 has a board connection terminal 9a, and has an arch shape surrounding the shaft 6c. The board side is in contact with the electronic component 101 on the circuit board 8 via the heat-dissipating sheet 10 which is compressed and deformed. ing. The motor cover 12 includes a motor cover 12 that covers the opening 1o of the cylindrical frame 1. The motor cover 12 has a bearing holding portion 12a and contacts the heat sink 9 via the high thermal conductor 11. Although a hole for taking out a lead terminal is formed in the center of the motor cover 12, it is closed by a terminal block (not shown), so that the sealing structure can be maintained. The high heat conductor is a material having high heat conductivity, and a heat conductive material such as a metal or a heat conductive resin can be used.

  The rotor 6 is rotatably disposed inside the stator 2 about a shaft 6c. At this time, the load-side bearing 6a is held by the cylindrical frame 1. On the other hand, the bearing 6 b on the non-load side is held by a bearing holding portion 12 a formed on the motor cover 12. The reason why the bearing holding portion 12a is formed on the motor cover 12 is to secure strength. Since the size and weight of the rotor increase as the output of the motor increases, there is a high possibility that a strong holding mechanism is required.

  The board case 7 is inserted into the cylindrical frame 1 from behind the stator 2. At this time, the output pins 5 inserted through the through holes 7a protrude toward the mounting surface side of the circuit board 8 in the board case 7, and are electrically connected to the circuit board 8 by soldering. Note that the DC brushless motor 201 is a three-phase drive motor that is often used for consumer use. In this case, three output pins 5 are provided for U-phase, V-phase, and W-phase. The diameter of the opening 7b of the board case 7 and the diameter of the opening 8a of the circuit board are larger than the diameter of the bearing 6b on the non-load side so that the rotor 6 can be inserted. The substrate case 7 is positioned in the axial direction by contacting the insulator 4 on the non-load side.

  A frame flange 1a and a cover flange 12b are formed on the outer peripheral portions of the open ends of the cylindrical frame 1 and the motor cover 12. The motor cover 12 is fitted over the tubular frame 1 and the cover flange 12b is brought into contact with the frame flange 1a and tightened with screws, thereby closing the opening 1o of the tubular frame 1. Note that the motor cover 12 and the heat sink 9 are in thermal contact with each other via the high thermal conductor 11. As the high thermal conductor 11 that intervenes the thermal contact between the motor cover 12 and the heat sink 9, an adhesive such as a silicon-based or epoxy resin-based adhesive is conceivable. In the first embodiment, the high thermal conductor 11 is interposed between the motor cover 12 and the heat sink 9, but the motor cover 12 and the heat sink 9 are joined by using a joining means such as screw tightening to make direct contact. Is also good.

  FIG. 2 is an enlarged view of a portion A in FIG. FIG. 3 is a top view of the circuit board in a state where the heat sink in FIG. 1 is connected. Hereinafter, the details of the heat dissipation structure in the first embodiment will be described with reference to FIGS. 2 and 3.

  The various electronic components 101 mounted on the circuit board 8 constitute various functions including a driving unit 101a, a control unit 101b, and a power supply unit 101c. The drive unit 101a is a combination of six discrete elements including a one-chip inverter IC (Integrated Circuit) or an IGBT (Insulated Gate Bipolar Transistor) and a motor driver IC. A configuration using a three-phase bridge driver is conceivable. Further, a configuration using a control element such as a microcomputer or a PLC (Programmable Logic Controller) can be considered as the control unit 101b. The power supply unit 101c has a power supply terminal connected to an external power supply. Furthermore, when an EMC (Electro Magnetic Compatibility) filter and an external power supply are AC power supplies, a configuration using an AC-DC converter can be considered.

  When an external power supply is supplied to the power supply unit 101c, the drive unit 101a energizes and drives the coil 2a according to a control command from the control unit 101b, thereby reducing the drive torque for rotating the rotor 6 connected to the load on the shaft 6c. generate. At this time, the main heat-generating components on the circuit board 8 are components constituting the drive unit 101a and the power supply unit 101c. Hereinafter, in the first embodiment, the heat generating component 101d in the driving unit 101a will be described as a heat radiation target.

  As shown in FIG. 2, the heat generating component 101 d is mounted on the circuit board 8, the upper surface is connected to the heat sink 9 via the heat radiation sheet 10, and the heat sink 9 contacts the motor cover 12 via the high thermal conductor 11. ing. For this reason, the heat radiation of the heat generating component 101 d is performed by heat transfer using the motor cover 12 that is in contact with the heat radiation sheet 10, the heat sink 9, and the high thermal conductor 11. The heat radiating sheet 10 improves the thermal conductivity between the heat generating component 101d and the heat sink 9, and also reduces the stress on the heat generating component 101d and the entire circuit board 8 due to an assembly error in the axial direction due to the compression deformation characteristic.

  As a member having the property of compressively deforming with respect to the stress, a substrate supporting portion 7c having a spring property is provided on the substrate case 7 as shown in FIG. It is also conceivable to provide them. The substrate supporting portion 7c having a spring property exerts a spring reaction force against the pressure applied to the heat generating component 101d and the entire circuit board 8 by the attachment of the heat sink 9 according to the law of elasticity. By designing the structure so that the stress and the reaction force of the spring are opposed to each other, it becomes possible to eliminate the heat radiation sheet 10 or to provide a configuration in which the high heat conductor 11 is interposed instead of the heat radiation sheet 10. As described above, the cost can be reduced by interposing the high heat conductor 11 in place of the heat radiation sheet 10.

  Next, the heat sink 9 increases the contact area with the motor cover 12 while avoiding interference with components other than the drawn portion 12c and the heat-generating component 101d and the output pin 5 formed when the bearing holding portion 12a is provided. For this reason, as shown in FIG. 3, an arch shape, that is, an arch shape surrounding the shaft 6c is formed when viewed from the axial direction. In the first embodiment, components other than the heat-generating component 101d are components of the power supply unit 101c. Although FIG. 3 shows a shape in which a part of the ring is missing, another shape such as a polygon may be used. The board connection terminal 9a is joined to the heat sink 9 by integral molding, caulking or screw tightening.

  When the heat sink 9 is pressed against the heat radiation sheet 10, the board connection terminals 9a are inserted into the through holes 8b on the circuit board 8, so that they are connected and fixed by soldering. As the connection method, any other conductive connection means or a mechanical connection using an adhesive may be used as long as a connection part having a high thermal conductivity can be obtained.

  In FIG. 3, the number of the board connection terminals 9a is three, but two or less or four or more in consideration of required heat radiation performance, mounting stability, or a margin for arrangement of the through holes 8b on the circuit board 8. It is good. The heat radiation performance is naturally higher as the number of substrate connection terminals 9a is larger. Further, the closer the position of the board connection terminal 9a is to the heat generating component 101d, the higher the heat transfer effect becomes.

  By adopting the configuration of the first embodiment, the circuit board 8 and the heat sink 9 are connected via the board connection terminals 9a. Therefore, the transmission of the heat-generating component 101d → the heat sink 9 → the motor cover 12 can be performed with a simple configuration and a simple manufacturing method. In addition to the heat path, a heat transfer path of the heat generating component 101d → the circuit board 8 → the heat sink 9 → the motor cover 12 is obtained. Thus, the heat radiation performance required for the DC brushless motor 201 can be ensured while keeping the material and manufacturing costs low.

Embodiment 2 FIG.
In order to further improve the heat radiation performance of the above-described heat radiation structure, the thermal resistance between the circuit board 8 and the heat sink 9 may be reduced. Hereinafter, in the second embodiment, a configuration for reducing the above-described thermal resistance will be presented with reference to FIGS. 5 and 6. FIG. 5 is a partial cross-sectional view of the DC brushless motor according to the second embodiment. FIG. 6 is a top view of the circuit board of the DC brushless motor according to the second embodiment to which a heat sink is connected. The circuit board 8 used in the DC brushless motor according to the second embodiment is made of the same material as the circuit pattern so as to be in thermal contact with the board connection terminals 9a in order to increase thermal conductivity with the heat sink 9 by the board connection terminals 9a. This is used to form a solid pattern for heat radiation which is patterned in the same step.

  First, the configuration shown in FIGS. 5 and 6 will be described. FIG. 5 shows a configuration in which the heat sink 9 in FIG. 2 has a contact surface 9c of the circuit board 8 to enhance thermal contact. On the circuit board 8, the first solid pattern 8d including the contact surface 8c with the heat sink 9 and the second main surface 8B opposite to the first main surface 8A which is the first solid pattern forming surface are formed. The solid pattern 8e is formed, and the heat radiation sheet 10a is formed so as to include the heat generating component 101d that generates heat and the contact surface 8c. FIG. 6 is a top view of the circuit board 8 to which the heat sink 9 in FIG. 5 is connected. The first solid pattern 8d is connected to the through hole 8b.

  According to the configuration shown in FIGS. 5 and 6, the heat sink 9 contacts the circuit board 8 at the contact surface 9c via the first solid pattern 8d having good thermal conductivity and the heat radiation sheet 10a. The thermal resistance between the substrates 8 can be reduced. In FIG. 6, the first solid pattern 8d including the contact surface 9c of the heat sink 9 with the circuit board 8 and the contact surface 8c on the circuit board 8 is provided in two places. One or three or more locations may be provided in consideration of the margin of the formation space of the solid pattern 8d.

  The heat radiation performance is naturally higher as the number and area of the contact surfaces 8c are larger. Further, as the arrangement of the contact surface 8c is closer to the heat generating component 101d, the heat transfer effect becomes higher. The first solid pattern 8d should naturally have a larger area from the viewpoint of exhibiting the effect of diffusing the heat generated by the heat-generating component 101d on the circuit board 8. However, countermeasures for securing creepage distances for compliance with the Electrical Appliance and Material Safety Law or the IEC standard (International Electrotechnical Commission: IEC), and preventing failure and malfunction due to various causes including external noise and lightning surge. -There is a restriction that the distance between the potentials is secured.

  Therefore, it is difficult to make the entire space without the electronic component 101, the output pin 5, or the pattern wiring into a solid pattern. Further, by bonding the through hole 8b to which the board connection terminal 9a is soldered to the first solid pattern 8d, the thermal resistance between the heat sink 9 and the circuit board 8 can be reduced. As shown in FIG. 5, when the solid pattern 8e formed on the surface opposite to the surface on which the first solid pattern 8d is formed is similarly coupled to the through hole 8b, the thermal resistance can be further reduced. The connection between the through hole and the solid pattern can be performed without increasing the cost by pattern design.

Embodiment 3 FIG.
Next, the configuration shown in FIGS. 7 to 9 will be described. FIG. 7 is a partial cross-sectional view of the DC brushless motor according to the third embodiment. FIG. 7 shows a configuration in which the circuit board 8 in FIG. 2 is formed of a multilayer board, and the second solid pattern 8h and the third solid pattern 8i of the second layer board 8f and the third layer board 8g are coupled to the through holes 8b. FIG. 8 and 9 are top views of the intermediate layer of the multilayer substrate in FIG.

  According to the configuration of the third embodiment shown in FIGS. 7 to 9, the through hole 8 b to which the board connection terminal 9 a is soldered is connected to the second solid pattern 8 h and the third solid pattern 8 i, thereby providing a heat sink. Thermal resistance between the circuit board 9 and the circuit board 8 can be reduced. The solid pattern may be formed on only one of the second layer substrate 8f and the third layer substrate 8g. The second solid pattern 8h and the third solid pattern 8i preferably have large areas, similarly to the solid patterns in the configurations shown in FIGS. 5 and 6, but are limited by the above-described creepage distance or distance between the earth potential. Therefore, it is difficult to make the entire space without the terminals of the electronic component 101, the output pins 5, and the pattern wiring into a solid pattern. In the third embodiment, a four-layer substrate is taken as an example. However, it goes without saying that the thermal resistance can be further reduced by increasing the number of substrate layers having a solid pattern coupled with the through-hole 8b by increasing the number of layers. . However, since the substrate cost increases as the number of layers increases, it is necessary to consider a balance between heat dissipation performance and cost.

  As described above, according to the DC brushless motors of the second and third embodiments shown in FIGS. 5 to 9, the rise in material cost is suppressed, and the structure and the manufacturing method are not complicated. Can be reduced, so that the heat radiation performance can be further improved at low cost.

  The through hole 8b for heat dissipation described in the first to third embodiments has no problem in terms of floating potential, but if connected to a specific potential, the GND potential is desirable. The GND potential is a reference potential of various DC power supplies for driving the driving unit 101a and the control unit 101b, and exhibits various noise suppression effects by being connected to a solid pattern.

Embodiment 4 FIG.
A DC brushless motor according to a fourth embodiment will be described. 10 is a partial sectional view of the DC brushless motor according to the fourth embodiment, FIG. 11 is an enlarged view of a portion B in FIG. 10, and FIG. 12 is a top view of a circuit board to which the heat sink according to the fourth embodiment is connected. is there. First, the overall configuration of the DC brushless motor 301 will be described with reference to FIG. The description of the parts having the same configuration as in the first embodiment is omitted, but the same parts are denoted by the same reference numerals.

  In the fourth embodiment, an opening is not provided at the center of the board case 307 and the circuit board 308. A bearing holding portion 307b is provided on the load side of the substrate case 307, and holds the bearing 6b on the non-load side. Along with this, a drawing portion 307c is formed on the load side of the substrate case 307.

  In the fourth embodiment, the cover 312 has no bearing holding portion and no drawing portion because the bearing holding portion 307b is provided in the substrate case 307. The cover flange 312a has the same configuration as that of the first embodiment.

  In the fourth embodiment, by covering the through-hole 307a with the moisture-proof sealing material 313, the installation space of the circuit board 308 is shielded from the outside air, so that the moisture resistance can be improved.

  FIG. 11 is an enlarged view of a portion B in FIG. FIG. 12 is a top view of the circuit board in a state where the heat sink in FIG. 11 is connected. Hereinafter, the details of the heat dissipation structure according to the fourth embodiment will be described with reference to FIGS. 11 and 12. The description of the same components as those in the second embodiment is omitted. The same parts have the same reference numerals.

  Since the heat sink 309 has no drawn portion on the motor cover 312, it is possible to increase the contact area with the motor cover 312 while avoiding interference with components other than the heat generating component 101 d and the output pins 5. In the fourth embodiment, components other than the heat-generating component 101d correspond to components of the power supply unit 101c. Although FIG. 12 shows a shape in which a part of the cylinder is missing, another shape such as a polygon may be used. The board connection terminal 309a has the same configuration as that of the first embodiment, and is joined to the heat sink 309 by integral molding or by various joining methods such as caulking or screw tightening.

  With the above-described structure, the circuit board 308 and the heat sink 309 are connected via the board connection terminals 309a in the DC brushless motor according to the second embodiment, and the heat-generating component can be manufactured with a simple configuration and a simple manufacturing method. In addition to the heat transfer path of 101d → heat sink 309 → motor cover 312, the heat transfer path of heat generating component 101d → circuit board 308 → heat sink 309 → motor cover 312 is obtained. As a result, the necessary heat radiation performance can be ensured even in the DC brushless motor 301 while keeping the material cost and the manufacturing cost low.

  The measures for reducing the thermal resistance described in the second and third embodiments with reference to FIGS. 5 to 9 can be applied similarly to the first embodiment. As a result, a rise in the cost of the DC brushless motor can be suppressed, and the thermal resistance between the circuit board 308 and the heat sink 309 can be reduced without complicating the configuration or the manufacturing method, thereby further improving the heat radiation performance at a low cost. Can be.

Embodiment 5 FIG.
The DC brushless motor having the heat dissipation structure described in the first to fourth embodiments is suitable for a system such as a ventilation blower that requires low cost and high productivity. Therefore, in a fifth embodiment, an example will be described in which the DC brushless motor described in the first to fourth embodiments is mounted on a ventilation blower.

  FIG. 13 is a cross-sectional view of a ventilation fan equipped with the DC brushless motor according to the first to fourth embodiments. The DC brushless motor 201 or 301 according to the first to fourth embodiments is mounted on the housing 402 of the ventilation fan 401, and the blower fan 403 is mounted on the shaft 6c. After the housing 402 is embedded in the ceiling plate 404, the grill 405 is attached from below.

  When the DC brushless motor 201 or 301 is energized, a driving torque is generated to rotate the blower fan 403. When the blower fan 403 rotates, an air flow indicated by an arrow in FIG. 13 is generated. The DC brushless motor 201 or 301 comes into contact with the housing 402 by the screw tightening of the frame flange and the cover flange described above. As a result, heat generated by the energization drive is transferred to the housing 402, so that a heat radiation effect is obtained.

  In the case of the DC brushless motor 301 according to the fourth embodiment, the circuit unit 406 and the motor unit 407 are separated by the moisture-proof substrate case 307 as described above. Accordingly, since the circuit portion 406 has a structure in which moisture hardly enters, the ventilation fan 401 can be used even in a high temperature and high humidity environment such as a bathroom.

  As described above, the ventilation fan equipped with the DC brushless motor according to the fifth embodiment has the heat radiation effect described in the first to fourth embodiments. Further, by installing a DC brushless motor, energy saving and downsizing of the ventilation fan can be realized at low cost. When the DC brushless motor according to the fourth embodiment is mounted, the moisture resistance can be improved.

  In the above-described embodiment, the motor cover made of metal is used. However, the motor cover is not limited to metal, and may be made of a heat conductive material such as a heat conductive resin.

  The configurations described in the above embodiments are merely examples of the contents of the present invention, and can be combined with other known technologies, and can be combined with other known technologies without departing from the gist of the present invention. It is also possible to omit and change parts.

  Reference Signs List 1 cylindrical frame, 1a frame flange, 1o opening, 2 stator, 2a coil, 3 load side insulator, 4 counter load side insulator, 5 output pin, 6 rotor, 6a load side bearing, 6b counter load Side bearing, 6c shaft, 7 substrate case, 7a through hole, 7b opening, 7c substrate support, 8 circuit board, 8a opening, 8b through hole, 8c contact surface, 8A first main surface, 8d first solid Pattern, 8B second main surface, 8e solid pattern formed on the opposite surface of the first solid pattern forming surface, 8f second layer substrate, 8g third layer substrate, 8h second solid pattern, 8i third solid pattern, 9 Heat sink, 9a Board connection terminal, 9c Contact surface, 10 heat dissipation sheet, 10a heat dissipation sheet, 11 high thermal conductor, 12 motor cover, 12a shaft Holding unit, 12b cover flange, 12c drawing unit, 101 electronic components, 101a driving unit, 101b control unit, 101c power supply unit, 101d heating component, 201 DC brushless motor, 301 DC brushless motor, 307 board case, 307a through hole, 307b bearing holding portion, 307c drawing portion, 308 circuit board, 309 heat sink, 309a board connection terminal, 312 motor cover, 312a cover flange, 313 moisture-proof sealing material, 401 ventilation fan, 402 housing, 403 blower fan, 404 ceiling plate, 405 grill, 406 circuit unit, 407 motor unit.

Claims (13)

A cylindrical frame made of a heat conductive material,
A stator mounted in the body of the cylindrical frame and provided with a coil,
A rotor arranged rotatably about a rotation axis,
A plurality of electronic components including a heat generating component is mounted, and a circuit board connected to the coil of the stator,
A heat sink having a first region in contact with the heat-generating component and a second region different from the first region in contact with the circuit board ;
A heat dissipation sheet having one surface in contact with the heat sink and the other surface in contact with the heat generating component and the circuit board;
A motor cover made of a heat conductive material that thermally contacts the heat sink and closes the first opening of the cylindrical frame ;
A substrate having one end contacting the heat sink and the other end contacting a fifth region of the circuit board which is different from a third region on which the heat-generating component is mounted and a fourth region corresponding to the second region; has a connection terminal, a,
The heat dissipation sheet is interposed between the heat generating component and the first area of the heat sink, and is interposed between the second area of the heat sink and the fourth area of the circuit board. DC brushless motor characterized by the above-mentioned. A first solid pattern for heat dissipation including the fourth area of the circuit board and a second solid pattern for heat dissipation including the fifth area of the circuit board are formed on the circuit board. DC brushless motor according to claim 1, characterized in that is. The DC brushless motor according to claim 2, wherein the first solid pattern and the second solid pattern are connected . 4. The DC brushless motor according to claim 1 , wherein the one end of the board connection terminal is in contact with a side surface of the heat sink . 5. The tubular frame and the motor cover are made of metal,
The stator is fitted in the body of the tubular frame,
The DC brushless motor according to any one of claims 1 to 4, wherein a board case made of an insulating material is mounted on the circuit board. The board case and the circuit board have a second opening at the center where the rotor is inserted,
6. The motor cover according to claim 5 , wherein the motor cover has a bearing holding portion, and the bearing on the non-load side of the rotor inserted into the second opening is held by the bearing holding portion of the motor cover. The DC brushless motor as described. The board case has a bearing holding part whose shape is processed on a load side,
The DC brushless motor according to claim 5 , wherein the bearing on the non-load side of the rotor is held by the bearing holding portion of the board case. The coil of the stator and the circuit board are connected by an output pin erected on the stator,
The board case has a through hole through which the output pin is inserted,
The DC brushless motor according to claim 5 , wherein the through-hole of the board case through which the output pin is inserted is closed with a moisture-proof seal material. The DC brushless motor according to claim 5 , wherein the board case includes a board supporting portion for elastically holding the circuit board. The circuit board has a through hole coupled to the second solid pattern,
DC brushless motors are pre Kimoto plate connecting terminal according to 請 Motomeko 2 or 3 shall be the feature that you have been inserted into the through hole. The circuit board is a multi-layer wiring board,
Said second solid pattern, DC brushless motor according to claim 2 or 3, characterized in that it is formed in the intermediate layer of the multilayer wiring board. DC brushless motor according to prior Symbol first and second solid pattern is characterized by a GND potential in the circuit board, according to claim 2 or 3.   A ventilation blower, comprising the DC brushless motor according to any one of claims 1 to 12.

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