JP2001159397A - Fan motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a high air quantity and a long service life with simple structure. SOLUTION: When a rotor boss part 4 supported to a bearing part 24 is rotated together with a fan blade 5, part of air that is about to be taken in from the fan blade 5 passes through an air passage 32, enters a motor chamber 7 and takes away heat generated from a stator 25 and heat generated from the bearing part 24. Temperature rise in the motor chamber 7 can thereby be reduced, and load applied to various parts constituting the stator 25, and load applied to the bearing part 24 can be reduced. This can be realized only by forming the air passage 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a fan motor such as an axial fan motor or a cross flow fan motor.

[0002]

Conventionally, for example, an axial fan motor having a rectangular outer shape has been used as a cooling blower mounted on various OA equipments. In this axial fan motor, a plurality of fan blades are provided on a peripheral wall of a rotor boss formed in a cup shape, and a bearing portion for axially supporting the rotor boss is provided in a motor chamber inside the rotor boss. When,
It has a structure in which a rotor is provided with a stator for imparting rotational force. Recently, as OA equipment has become smaller, smaller size, higher air volume and longer life are required. It has become.

However, if an attempt is made to reduce the external shape of the axial fan motor, the load on the internal circuits, windings and cores constituting the stator increases, the temperature inside the motor chamber rises remarkably, and the rotor boss portion is increased. The load on the bearing portion that supports the shaft increases. Further, since a method such as increasing the rotation speed of the rotor boss portion is used to achieve a high air flow, the load on the bearing portion is further increased. And
Such an increase in the load on each part is a factor for shortening the life of the axial fan motor, and it has been more difficult to achieve a long life.

[0004] In order to avoid such a problem, conventionally, specifications such as grease and structure in a bearing portion have been changed. However, such a change in specifications is often less versatile, and in the end, it becomes necessary to prepare a unique bearing for each of the various axial flow fan motors, and there is a concern that the cost of the bearing may become relatively high.

On the other hand, a cross-flow fan motor used for cooling the inside of a copying machine includes a casing, a rotatable cross-flow fan arranged in the casing,
A drive circuit for the motor unit is housed in a motor case provided outside the one side of the casing. In such a cross-flow fan motor, a high flow rate of the cross-flow fan is required similarly to the axial fan motor, but in order to increase the output of the motor section, a large current is applied to a drive circuit of the motor section. Then, the temperature rise of the integrated circuit (IC), which is the main component of the drive circuit, is particularly large, and the temperature rise of each component of the drive circuit other than the integrated circuit, the circuit board, etc. is also large. There was a problem that it could not be handled.

An object of the present invention is to solve the above problems, and an object of the present invention is to provide a fan motor capable of achieving a high air flow and a long life with a simple structure.

[0007]

According to the fan motor of the first aspect of the present invention, when the rotor boss supported by the bearing rotates together with the fan blade, one of the air to be taken in from the fan blade is removed. The portion passes through the air flow path and enters the motor chamber, where it takes heat generated from the stator and heat generated from the bearing portion. Therefore, the temperature rise in the motor chamber can be reduced, and the load on various components constituting the stator and the load on the bearing portion can be reduced. This can be realized by simply forming an air flow path without changing the specifications such as grease and structure in the bearing part. Therefore, there is almost no increase in cost, and a simple structure achieves high air volume and long life. Can be achieved.

According to the fan motor of the second aspect of the present invention, when the crossflow fan rotates in the casing by driving the motor section, the crossflow fan is drawn into the air flowing through the casing, and particularly generates a large amount of heat. Heat generated from the integrated circuit and other components of the drive circuit is discharged from the heat radiation holes communicating with the inside of the casing. Therefore, the temperature rise and the load of these integrated circuits and other components can be reduced. This can be realized by simply forming a heat radiating hole in the motor case and providing a hole in the casing to allow the heat radiating hole to communicate with the inside of the casing. The structure makes it possible to achieve a high air volume and a long life.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the fan motor according to the present invention will be described with reference to the accompanying drawings.

FIGS. 1 to 6 show a first embodiment of the present invention. The fan motor in this embodiment is a so-called thin rectangular axial fan motor having a thickness of 15 mm or less in the front-rear direction, that is, in the axial direction.

1 and 2, reference numeral 1 denotes a rotatable rotor, that is, a rotor which covers a substantially cylindrical yoke 3 having a magnet 2 fixed to an inner peripheral surface and an outer surface of the yoke 3. Cup-shaped rotor boss 4 attached to
A plurality of fan blades 5 provided on a peripheral wall of the rotor boss 4, and a rotating shaft 6 press-fitted into the center of the rotor boss 4.
It is composed of The rotor boss 4 is formed integrally with the fan blade 5, and a motor chamber 7, which will be described later, is formed on a portion of the rotor boss 4 surrounded by the motor chamber facing surface 4 </ b> A and the peripheral wall. You.

Reference numeral 11 denotes a housing that forms the outer shell of the rectangular axial fan motor. The housing 11 surrounds the fan blade 5 and has an air inlet at one end and the other end.
And a motor case 16 forming the other surface, ie, the bottom surface, of the motor chamber 7 located on the exhaust port 13 side. 16 and 17 are connected by thin radial spokes 17.
Also, radially outward from the intake port 12 and the exhaust port 13,
A flange portion 18 for fixing the housing 11 to another external member (not shown) is formed. The outer peripheral surface of the flange portion 18 is formed in a substantially rectangular shape so as to be in contact with the outer peripheral wall of the cylindrical portion 14, and a mounting hole 19 is formed at each corner of the flange portion 18.

A hole 21 formed in the center of the motor case 16
Has a cylindrical bearing tube 22 erected along the axial direction.
Is fixed. A pair of front and rear bearings 23 for supporting the rotary shaft 6 are provided on the inner surface of the bearing tube 22. The rotor tube 6 and the bearing 23 allow the rotor boss portion 4 and thus the rotation around the rotary shaft 6. A bearing portion 24 for rotatably supporting the whole child 1 is formed. On the other hand, on the outer surface of the bearing tube 22, a stator 25 for applying a rotational force to the rotor 1 is disposed. Stator 25 is a bearing tube
And a bobbin 27 attached to the core 26.
, The core 26 and the motor case 16
And a circuit board 30 on which various electronic components 29 are mounted facing the motor case 16 side. The stator 25 and the bearing 24 are both provided inside the motor chamber 7.

An air passage 32 penetrating the motor chamber facing surface 4A and the motor chamber 7 is formed on the motor chamber facing surface 4A of the substantially flat rotor boss portion 4 formed facing the intake port 12. A plurality of openings are formed. In this embodiment, each of the air passages 32 is formed in parallel in the axial direction such that the opening on the side of the motor chamber 7 just faces the winding 28. The shape and number of the air passages 32 are not limited to those in the embodiment. Other modifications of the air passage 32 will be described later in detail. The motor chamber 7 is not completely closed by the rotor boss 4 and the motor case 16. A gap 33 formed between the chamber facing surface and the motor case 16 communicates with the outside of the motor chamber 7.

Next, the operation of the above configuration will be described with reference to the perspective view of FIG. Winding 28 from circuit board 30
The magnet 2 of the rotor 1 receives electromagnetic force from the stator 25 at a predetermined timing, and the entire rotor 1 including the rotor boss 4 and the fan blade 5 is centered on the rotation shaft 6. To rotate. With the rotation of the rotor 1, most of the air on one surface side of the housing 11 is taken into the cylindrical portion 14 from the intake port 12, and between the adjacent fan blades 5 or between the fan blades 5 and the cylindrical portion 14. After passing through the space, the air is discharged to the outside from an exhaust port 13 on the other surface side of the housing 11.

On the other hand, the air taken in from the air inlet 12 toward the front surface of the fan blade 5 does not pass between the adjacent fan blades 5 but hits one side surface of the fan blade 5. This air receives the rotational force of the fan blade 5 from there and flows in an arc shape toward the rotating shaft 6 at the center of the rotor 1 along the motor chamber facing surface 4A of the rotor boss 4 (FIG. 4), and enters the interior from the air passage 32 on the motor chamber facing surface 4A of the rotor boss portion 4. At this time, since the rotational force of the rotor boss portion 4 acts on the air passing through the air flow path 32, the air uniformly flows into the motor chamber 7 together with the rotational force of the fan blade 5. It is captured. In the motor chamber 7, the core 26, the winding 28 and the circuit board constituting the stator 25 are mounted.
The air flows toward the other side of the housing 11 while depriving the heat generated from each electronic component 29 of the 30 and the frictional heat generated from the bearing portion 24 accompanying the rotation of the rotating shaft 6 uniformly, and finally the air flows toward the other side of the housing 11. Is the surface of the rotor boss portion 4 opposite to the motor chamber and the motor case 16
Air is sent out into the cylindrical portion 14 on the other side of the fan blade 5 from the gap 33 formed between the cylindrical portion 14 and the fan blade 5.

As described above, in the above embodiment, a plurality of fan blades 5 are provided on the peripheral wall of the rotor boss 4 formed in a cup shape, and the motor chamber 7 inside the rotor boss 4 is provided.
In addition, a bearing portion 24 for rotatably supporting the rotor boss portion 4 is provided.
In the fan motor provided with the rotor 25 and the stator 25, an air flow path 32 penetrating the motor chamber facing surface 4A of the rotor boss 4 and the motor chamber 7 is formed.

In this case, when the rotor boss portion 4 supported by the bearing portion 24 rotates together with the fan blade 5, a part of the air to be taken in from the fan blade 5 passes through the air flow path 32 and the motor It enters the chamber 7 and takes heat generated from the stator 25 and heat generated from the bearing portion 24 here. Therefore, the temperature rise in the motor chamber 7 can be reduced, and various components (the core 26, the windings 28,
The load on the electronic component 29) and the load on the bearing 24 can be reduced. This can be realized by simply forming the air flow path 32 without changing the specifications of the grease and the structure in the bearing portion 24, so that the cost is hardly increased and the airflow is increased by a simple structure. And a longer life can be achieved.

Also, in this embodiment, a gap 33 is formed between the opposite surface of the rotor boss portion 4 opposite to the motor and the motor case 16 which forms the rear surface of the motor chamber 7. It serves as an exhaust port for the air passing through the inside of the motor chamber 7, so that the air that has taken heat from the bearing portion 24 and the stator 25 can be quickly discharged without being trapped in the motor chamber 7. Further, in the present embodiment, in the motor room 7, various parts of the stator 25 (the core 26, the winding 28, the electronic
9), the air flowing in an arc toward the center of the rotor 1 while being along the motor chamber facing surface 4A of the rotor boss portion 4 by receiving the rotational force of the fan blade 5, Bearing part arranged at the center in motor room 7
By effectively removing the heat from the motor 24 and receiving the rotational force of the rotor boss 4, the air flowing along the rotation direction of the rotor boss 4 in the motor chamber 7 is around the bearing 24. The heat from the various components of the stator 25 is effectively removed, and the heat is uniformly removed in the motor chamber 7 while the gap 33 is removed.
It is exhausted from. Therefore, it is possible to further improve the cooling performance.

The air passage 32 is formed not only at right angles to the motor chamber facing surface 4A of the rotor boss 4 but also at right angles.
For example, it may be formed to be inclined at 45 °. Modifications are shown in FIGS. In FIG. 5, each air passage 32 is formed toward the rotation shaft 6 at the center of the rotor 1. In this case, since a relatively large amount of air flows toward the bearing portion 24 at the center of the motor chamber 7, it is effective particularly when the temperature of the bearing portion 24 is significantly increased. In FIG. 6, each air flow path 32 is formed obliquely along the rotation direction of the rotor 1. In this case, a relatively large amount of air flows toward various parts of the stator 25 around the bearing portion 24,
This is particularly effective when the temperature of the stator 25 rises significantly.

Next, a second embodiment of the present invention will be described with reference to FIGS.
It will be described based on. Note that the fan motor in this embodiment is a cross-flow fan motor. In FIG. 7 showing the overall configuration, reference numeral 41 denotes a horizontally long cylindrical cross flow fan having a plurality of fan blades on an outer peripheral portion.
It is rotatably arranged in the fan storage section 43 of 42. One end of the cross flow fan 41 is connected to a motor unit 44 composed of a DC brushless motor, and the other end of the cross flow fan 41 is supported by a bearing assembly 45.

The basic structure of the motor section 44 for transmitting the rotational force to the cross flow fan 41 is substantially the same as that of the first embodiment. That is, as shown in FIG. 8, reference numeral 51 denotes a rotor assembly as a rotor mounted coaxially with the cross flow fan 41. The rotor assembly 51 includes a cup-shaped yoke 53 to which a magnet 52 is fixed, and one end of the cross flow fan 41. And a fixing bracket 55 for fixing the rotating shaft 54 to the center of the yoke 53. Also, facing the opening end surface of the yoke 53,
For example, a motor case 56 made of a synthetic resin is provided, and a stator 58 for applying a rotational force to the rotor assembly 51 is provided in a motor chamber 57 surrounded between the motor case 56 and the yoke 53. . At the center of the motor case 56, a cylindrical bearing tube extending toward the yoke 53 along the axial direction of the rotating shaft 54
The bearing tube 59 and the bearing 60 inside the bearing tube 59 constitute a bearing portion 61.
On the other hand, the stator 58 includes a core 63 fixed to the outer surface of the bearing tube 59, a winding 64 wound around the core 63, and a concave circuit housing portion 65 formed on one side of the motor case 56. It is housed, and includes a circuit board 68 on which various electronic components 67 (see FIG. 9) are mounted in addition to an integrated circuit (IC) 66 which generates particularly large heat. The electronic components including the integrated circuit 66 and the circuit board 68 constitute a circuit assembly 69 which is a drive circuit of the motor unit 44.

The circuit housing 65 is provided with a heat radiating hole 71 at a position facing the integrated circuit 66. Further, as shown in FIG. 9, two heat radiating holes 72 are also provided at a position facing another circuit board 68 not facing the integrated circuit 66. Heat dissipation hole
Reference numeral 71 denotes a substantially circular opening facing the center of the integrated circuit 66, and the other heat radiating holes 72 are cross-flow fans regardless of other electronic components 67 mounted on the circuit board 68.
An opening is formed in an arc shape along the rotation direction of 41. In addition,
73 casing the motor part 44 using screws (not shown)
It is a screw insertion hole for attaching and fixing to one side outside of 42.

The construction of the casing 42 will be described with reference to FIGS. 10 and 11. The casing 42 comprises a pair of left and right side plates 77, 78, a curved guide plate 79 disposed between the side plates 77, 78, and a side plate. A cross section that is disposed between 77 and 78 and that partitions an intake port 80 and an exhaust port 81 orthogonal to each other is generally constituted by a U-shaped partition plate 82. A hole 83 is formed in the side plate 77 to which the motor unit 44 is attached, for opening the heat radiation holes 71 and 72 to the fan housing 43 in the casing 42. The hole portion 83 is formed to have a size that allows a step portion 84 formed on the other side of the motor case 56 to be inserted. When the motor portion 44 is fixed to the casing 42, the heat radiation holes 71,
72 directly faces the side of the cross flow fan 41.

Next, the operation of the above configuration will be described. By passing a drive current from the circuit board 68 to the winding 64 at a predetermined timing, the magnet 52 of the rotor assembly 51 receives an electromagnetic force from the stator 58, and the rotor assembly 51 and the cross flow fan 41 rotate around the rotation shaft 54. To rotate. With the rotation of the cross flow fan 41, the air taken in from the intake port 80 of the casing 42 passes through the fan storage section 43 along the guide plate 79, and the exhaust port in a direction orthogonal to the intake port 80.
It is discharged outside from 81.

The air taken in from the gap 85 between the rotating yoke 53 and the motor case 56 along with the flow of the air flows between the outer peripheral side surface of the circuit board 68 and the side wall of the circuit housing portion 65. Pass the space between the bottom of the circuit
It enters between 68 component mounting surfaces. Then, while depriving heat generated from the integrated circuit 66 and other electronic components 67 as heat-generating components, the heat flows through the heat radiation holes 71 and 72 to the fan housing 43 of the casing 42, and the fan The air merges with the air in the storage section 43 and is discharged to the outside through the exhaust port 81. Among the heat dissipated from the integrated circuit 66, the heat particularly toward the bottom surface of the circuit housing portion 65 is the heat radiation hole 71 located at the opposed position.
Is effectively discharged from In addition, heat generated from the integrated circuit 66 along the component mounting surface of the circuit board 68 and other electronic components.
The heat generated from the circuit board 67 and the circuit board 68
Other heat radiating holes to be drawn into the air flow inside
Effectively discharged from 72. In particular, in this embodiment,
Since 72 has a shape along the rotation direction of the cross flow fan 41, that is, the shape along the flow of air in the fan housing 43, the space between the bottom surface of the circuit housing 65 and the component mounting surface of the circuit board 68 is provided. Heat can be quickly discharged without stagnation.

The following Table 1 shows the experimental results showing the correlation between the heat radiation holes 71 and 72 and the temperature rise of the circuit assembly 69. This table shows the conventional specifications that do not have any heat radiation holes 71 and 72 (no heat radiation holes), those that have only one heat radiation hole 71 facing the IC part, that is, the integrated circuit 66 (one heat radiation hole), In addition to the radiating hole 71 facing the circuit 66, another radiating hole 72
Related to the present invention (two heat radiation holes), integrated circuit 6
6 relating to the present invention (three heat radiating holes) provided with two other heat radiating holes 72 in addition to the heat radiating hole 71 opposed to 6, the largest temperature rise in the integrated circuit 66 and the largest temperature rise in the circuit board 68. Is the data obtained by actually measuring.

[0028]

[Table 1]

As is clear from this table, the provision of only one heat radiating hole 71 makes each part of the circuit assembly 69 in comparison with a conventional cross flow fan motor having no heat radiating holes 71 and 72 at all. Although the temperature rise hardly changes, if one or more other heat radiating holes 72 are formed in addition to the heat radiating holes 71, the temperature rise of each part in the circuit assembly 69 is significantly reduced.

As described above, this embodiment comprises the casing 42, the rotatable cross flow fan 41 disposed in the casing 42, and the motor section 44 for driving the cross flow fan 41. A circuit assembly 69 which is a drive circuit of the unit 44 is housed in a motor case 56 provided outside one side of the casing 42.
Have heat radiation holes 71 and 72 at one or a plurality of other positions facing the integrated circuit 66 as a heat-generating component which is a component of the circuit assembly 69. The heat radiation holes 71 and 72 and the casing 42 A hole 83 for communicating the inside is provided in the casing 42.

In this case, when the cross-flow fan 41 rotates in the casing 42 by driving the motor section 44, the cross-flow fan 41 is drawn into the air flowing through the casing 42, so that the integrated circuit 66, which generates a particularly large amount of heat, and the like. The heat generated from the components of the circuit assembly 69 (the electronic component 67 and the circuit board 68) is discharged from the heat radiation holes 71 and 72 communicating with the inside of the casing 42. Therefore, the temperature rise and the load of the components of the integrated circuit 66 and the circuit assembly 69 can be reduced. This is simply because the motor case 56 has heat radiation holes 71 and 72
Can be realized simply by providing the casing 42 with the holes 83 for communicating the heat radiation holes 71 and 72 with the inside of the casing 42. Therefore, the cost is hardly increased, and the air volume can be increased by a simple structure. And a longer life can be achieved.

In this embodiment, a gap 85 is formed between the rotor assembly 51 and the motor case 56, and another gap is formed between the outer peripheral side surface of the circuit board 68 and the side wall of the circuit housing portion 65. Are formed, these serve as air intake passages between the bottom surface of the circuit housing portion 65 and the component mounting surface of the circuit board 68, and take heat from the components of the integrated circuit 66 and the circuit assembly 69. The air can be quickly discharged into the casing 42. Further, since the heat radiation hole 72 in the present embodiment has a shape along the rotation direction of the cross flow fan 41, it does not stay between the bottom surface of the circuit housing portion 65 and the component mounting surface of the circuit board 68. Heat can be discharged more quickly.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made. For example, the hole shapes of the air flow path 32 and the heat radiation holes 71 and 72 are not particularly limited to those in the embodiment, such as a square, a triangle, an ellipse, and a polygon, as well as a circle.

[0034]

According to the fan motor of the first aspect of the present invention, it is possible to achieve a high air volume and a long life with a simple structure.

According to the fan motor of the second aspect of the present invention,
With a simple structure, it is possible to achieve high air volume and long life.

[Brief description of the drawings]

FIG. 1 is a front view of a rectangular axial fan motor according to a first embodiment of the present invention.

FIG. 2 is a side view of the rectangular axial flow fan motor.

FIG. 3 is a cross-sectional view of the square axial-flow fan motor when the same is used.

FIG. 4 is a perspective view of a rectangular axial-flow fan motor in which the flow of air during the same operation is visualized.

FIG. 5 is a front view of a rectangular axial fan motor showing another modification of the embodiment.

FIG. 6 is a front view of a rectangular axial flow fan motor showing still another modified example of the embodiment.

FIG. 7 is a front view of a cross flow fan motor according to a second embodiment of the present invention.

FIG. 8 is a partially cutaway sectional view of the motor unit.

FIG. 9 is a side view of the motor case.

FIG. 10 is a front view of the casing.

FIG. 11 is a sectional view taken along line AA of FIG. 10;

[Explanation of symbols]

 4 Rotor boss part 5 Fan blade 7 Motor room 24 Bearing part 25 Stator 32 Air flow path 41 Cross flow fan 42 Casing 44 Motor part 56 Motor case 66 Integrated circuit 69 Circuit assembly (drive circuit) 71,72 Heat radiating hole 83 hole Department

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 7/14 H02K 7/14 A 5H609 9/06 9/06 F 5H621 21/22 21/22 MF term (Ref.) DD01 DD02 DD03 DD08 DD19 FF04 FF05 FF12 GG08 5H609 BB15 BB18 PP02 PP05 PP06 PP07 PP08 PP09 PP10 PP11 QQ02 QQ12 QQ13 QQ17 RR17 RR27 RR43 RR70 5H621 GA01 HH01 JK07 JK08 JK11 JK14 JK17 JK17

Claims (2)

[Claims] A bearing for providing a plurality of fan blades on a peripheral wall of a rotor boss formed in a cup shape and rotatably supporting the rotor boss in a motor chamber inside the rotor boss. In a fan motor provided with a portion and a stator, an air flow passage penetrating the motor chamber facing surface of the rotor boss portion and the motor chamber is formed. 2. A casing, a rotatable cross flow fan disposed in the casing, and a motor unit for driving the cross flow fan, wherein a drive circuit of the motor unit is provided outside one side of the casing. In the fan motor housed in the provided motor case, the motor case has a heat radiating hole at a position facing the integrated circuit which is a component of the drive circuit and at one or more other positions. A hole is provided in the casing to allow communication between the casing and the inside of the casing.