JP2001251813A - Motor and electronic device provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor and electronic device provided with the motor, where lubricating oil is prevented from being reduced through an opening in a bearing, even if a hole for sucking air is positioned on the lower side. SOLUTION: The motor comprises a rotor 20, having a shaft and impellers rotating together with the shaft, a bearing 42 for rotatably supporting the shaft, a stator 22 which rotates the rotor 20 by magnetic interaction, and a casing 41 which houses the rotor 20 and the stator 22 and has air inlet holes 100, through which air is let in by the rotation of the impellers 31 and an air discharge hole 130 through which the air introduced is discharged to the outside. The bearing 42 is provided with a thrust-receiving portion 70 which rotatably supports an end of the shaft, further contains the lubricating oil in the bearing 42, and the air inlet holes 100 are formed in the casing 41 on the thrust receiving portion 70 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor and an electronic device having the motor.

[0002]

2. Description of the Related Art For example, electronic equipment such as a portable computer is provided with a fan motor for cooling the inside. 9 to 11 show examples of a conventional fan motor. A conventional fan motor has a rotor 100
0 and a stator 1001, and a shaft 1002 of the rotor 1000 is rotatably supported by a bearing 1003 of the stator 1001. The rotor 1000 and the stator 1001 are housed in a casing 1005, and the rotor 1000 has an impeller (blade) 1006. When the impeller 1006 of the rotor 1000 continuously rotates in the R1 direction due to magnetic interaction with the side of the stator 1001, for example, air in the housing of the computer enters the F1 direction from the wind inlet 1010, and the air outlet 1020 To the direction F2.

[0003]

However, in this type of fan motor, as shown in FIG. 9, the bearing 1003 rotatably supports the shaft 1002, but the bearing opening 1030 has the wind suction port 1010 as shown in FIG. Open to the side.
For this purpose, for example, when the fan motor is arranged in the vertical direction along the Z direction as shown in FIG. 9 and FIG.
Then, since the wind suction port 1010 is located on the lower side, there is a problem that the lubricating oil in the bearing 1003 leaks out from the bearing opening 1030 and goes out into the housing of the computer. That is, there is a possibility that the lubricating oil in the bearing 1003 will fall by its own weight, drop downward and decrease with time, and come out of the housing of the computer.

In general, the amount of residual oil in the bearing 1003 needs to be about 40% of the amount of the lubricating oil initially filled in the bearing 1003. Must be prevented as much as possible.
Therefore, the present invention solves the above problems, and provides a motor and an electronic device including the motor that can prevent the lubricating oil from decreasing from the opening of the bearing even if the hole for sucking the wind is located on the lower side. It is intended to provide.

[0005]

The invention according to claim 1 has a shaft, a rotor having an impeller that rotates with the shaft, and a bearing for rotatably supporting the shaft.
A stator that rotates the rotor by magnetic interaction, an air introduction hole that accommodates the rotor and the stator and introduces air by rotation of the impeller, and an air exhaust hole that exhausts the introduced air to the outside. A bearing having a thrust receiving portion rotatably supporting an end of the shaft and confining lubricating oil in the bearing, wherein the air introduction hole is provided in the casing. A motor is provided on the thrust receiving portion side.

According to the first aspect, the rotor has a shaft and an impeller that rotates with the shaft. The stator has bearings for rotatably supporting the shaft so that the rotor can be rotated by magnetic interaction. The casing houses the rotor and the stator, and has an air introduction hole for introducing air by rotation of the impeller and an air discharge hole for discharging the introduced air to the outside. This bearing is
The end of the shaft is rotatably supported, and has a thrust receiving portion for containing the lubricating oil in the bearing. Moreover, the air introduction hole is provided on the thrust receiving portion side in the casing. Accordingly, even if the air introduction hole side of the casing is located on the lower side, the lubricating oil does not leak from the bearing because the thrust receiving portion confines the lubricating oil. That is, it is possible to prevent the lubricating oil from dropping under its own weight, which greatly affects the life of the bearing, and to ensure long-term reliability of the motor.

According to a second aspect of the present invention, in the motor according to the first aspect, the bearing has a bottom portion for rotatably supporting the shaft, and a cylindrical portion integrated with the bottom portion. The thrust receiving portion, wherein the shaft is inserted into the cylindrical portion via a bearing metal. According to the second aspect, the bearing has a bottom portion and a cylindrical portion integrated with the bottom portion for rotatably supporting the shaft. The bottom portion is a thrust receiving portion, and the shaft is inserted into the cylindrical portion via a bearing metal.

According to a third aspect of the present invention, in the motor according to the first aspect, the rotor is provided with a magnet, and the stator is provided with a drive coil. Due to the magnetic interaction between the rotor and the drive coil, the rotor continuously rotates.
According to the third aspect, by energizing the drive coil, the rotor continuously rotates due to the magnetic interaction between the magnet and the drive coil.

According to a fourth aspect of the present invention, in the motor according to the second aspect, when the motor is disposed in the electronic device, the air introduction hole and the thrust receiving portion are located below the electronic device. The impeller is located above the electronic device, and the upper end of the shaft is located at the first end of the casing.
A lower end of the shaft is rotatably supported by a second thrust receiver in the bottom of the bearing. According to claim 4, when the motor is arranged in the electronic device, the air introduction hole and the thrust receiving portion are located below the electronic device, and the impeller is located above the electronic device. The upper end of the shaft is rotatably supported by the first thrust receiving member of the casing, and the lower end of the shaft is rotatably supported by the second thrust receiving member provided in the bottom of the bearing. Thus, the shaft is rotatably supported between the first and second thrust receivers, so that the rotor having the shaft does not move in the axial direction with respect to the stator. Thus, stable rotation of the rotor can be obtained without magnetically attracting the shaft of the rotor in the axial direction to stop the movement of the shaft in the axial direction.

According to a fifth aspect of the present invention, there is provided a stator having a shaft, a rotor having an impeller rotating with the shaft, and a bearing for rotatably supporting the shaft, and rotating the rotor by magnetic interaction. A casing having an air introduction hole that accommodates the rotor and the stator and introduces air by rotation of the impeller, and an air discharge hole that exhausts the introduced air to the outside, The bearing is disposed in a housing of the electronic device, the bearing has a thrust receiving portion rotatably supporting an end of the shaft and enclosing lubricating oil in the bearing, and the air introduction hole is An electronic device comprising a motor provided on the thrust receiving portion side of the casing.

According to the fifth aspect, the rotor has a shaft and an impeller that rotates with the shaft. The stator has bearings for rotatably supporting the shaft so that the rotor can be rotated by magnetic interaction. The casing houses the rotor and the stator, and has an air introduction hole for introducing air by rotation of the impeller and an air discharge hole for discharging the introduced air to the outside. This bearing is
The end of the shaft is rotatably supported, and has a thrust receiving portion for containing the lubricating oil in the bearing. Moreover, the air introduction hole is provided on the thrust receiving portion side in the casing. Thus, even if the air introduction hole side of the casing is located on the lower side, the thrust receiving portion confines the lubricating oil, so that the lubricating oil does not leak from the bearing. That is, it is possible to prevent the lubricating oil from dropping under its own weight, which greatly affects the life of the bearing, and to ensure long-term reliability of the motor.

According to a sixth aspect of the present invention, in the electronic device provided with the motor according to the fifth aspect, the bearing of the motor includes a bottom portion for rotatably supporting the shaft and a cylindrical portion integrated with the bottom portion. Wherein the bottom portion is the thrust receiving portion, and the shaft is inserted into the cylindrical portion via a bearing metal. According to claim 6, the bearing has a bottom portion and a cylindrical portion integrated with the bottom portion for rotatably supporting the shaft. The bottom portion is a thrust receiving portion, and the shaft is inserted into the cylindrical portion via a bearing metal.

According to a seventh aspect of the present invention, there is provided an electronic apparatus comprising the motor according to the fifth aspect, wherein the rotor of the motor is provided with a magnet, the stator is provided with a drive coil, and the drive coil is provided with a drive coil. , The rotor rotates continuously due to the magnetic interaction between the magnet and the drive coil. According to the seventh aspect, by energizing the drive coil, the rotor rotates continuously due to the magnetic interaction between the magnet and the drive coil.

According to an eighth aspect of the present invention, in the electronic device provided with the motor according to the sixth aspect, when the motor is disposed in the electronic device, the air introduction hole and the thrust receiving portion are connected to the electronic device. The lower side, the impeller is located above the electronic device, the upper end of the shaft is rotatably supported by a first thrust receiver of the casing, the lower end of the shaft is in the bottom of the bearing A certain second
It is rotatably supported by the thrust receiver. Claim 8
In the state where the motor is arranged in the electronic device, the air introduction hole and the thrust receiving portion are located below the electronic device,
An impeller is located above the electronic device. The upper end of the shaft is rotatably supported by the first thrust receiving member of the casing, and the lower end of the shaft is rotatably supported by the second thrust receiving member provided in the bottom of the bearing. Thus, the shaft is rotatably supported between the first and second thrust receivers, so that the rotor having the shaft does not move in the axial direction with respect to the stator. Even without devising to stop the movement of the shaft in the axial direction by magnetically attracting the shaft of the rotor in the axial direction,
Stable rotation of the rotor is obtained.

[0015]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these modes unless otherwise specified in the following description.

FIG. 1 shows a portable computer as a preferred embodiment of an electronic apparatus having a motor according to the present invention. The computer 1 shown in FIG. 1 has a display unit 2 and a main body 3, and the display unit 2 is supported on the main body 3 by a connecting unit 4 so as to be opened and closed. The main body 3 has a keyboard 5, a housing 12, a motor 10, and the like.

FIG. 2 shows an example of a sectional structure taken along the line AA in FIG. In FIG. 2, the motor 10 of the present invention is built in the housing 12, and the motor 10 is used as a fan motor for cooling the inside of the housing 12 of the main body 3. The motor 10 includes a rotor 20 and a stator 2
Two. The motor 10 is mounted on the housing 1 as described above.
2, and the warmed air in the housing 12 is discharged from the direction T1 to the direction T2, so that the housing 1
The heat-generating electronic components 92 and the like in 2 are cooled. As shown in FIG. 2, for example, a circuit board 90 is disposed in the housing 12, and the circuit board 90 is, for example, an electronic component 92 that generates heat during operation such as a CPU (Central Processing Unit) or a driver. Is installed.

FIG. 3 shows an enlarged view of the structure of the motor 10 of FIG. FIG. 4 shows the appearance of the motor 10. The motor 10 has a rotor 20, a stator 22, and a casing 41. The rotor 20 includes a rotor case 29, a shaft 28, a main magnet 30, and an impeller 31.
have. The rotor case 29 is made of, for example, iron, and the shaft 28 is made of stainless steel. The main magnet 30 is, for example, a neody plastic magnet. The impeller 31 is formed of, for example, ABS (acrylonitrile butadiene styrene) resin or polycarbonate (PC).
The upper end of the shaft 28 is fixed to the hole 29A of the rotor case 29 by press fitting. The main magnet 30 has a multi-polarized N-pole and S-pole. As shown in FIG. 5, a plurality of impellers 31 are arranged at equal intervals around the outer periphery of the rotor case. Impeller 31
Has, for example, a structure of seven blades as shown in FIG.
As shown in FIG. 7, for example, an angle of θ, for example, about 50 °
At an angle of. This impeller 31
By rotating in the direction R in FIG. 5 at, for example, about 5500 rpm, air can be sucked in the direction T1 shown in FIGS. 2 and 3 and blown out in the direction T2.

The main magnet 30 shown in FIG. 3 employs a neody plastic magnet as described above.
For example, four N poles and S poles are alternately magnetized. The rotation amount of the main magnet 30 can be detected by the sensor 200 shown in FIG. This sensor 200 is, for example, a Hall element made of gallium arsenide,
One sensor 200 can output a two-phase output change signal. The rotor case 29 is used to form a magnetic circuit.
An iron plate is formed by drawing. The upper end 28A and the lower end 28B of the shaft 28 are both polished in a round shape.

Next, the stator 22 shown in FIG. 3 will be described. The stator 22 includes a bearing 42, a stator yoke 5
4, a coil 43 and the like. The bearing 42 has a bearing housing 52 and a bearing metal 55. The bearing housing 52 of the bearing 42 is, for example, an aluminum die-cast, and a bearing holder 56 is fixed to the bearing housing 52. This bearing holder 56
Is a cylindrical member, and a bearing metal 55 is accommodated in the bearing holder 56. The shaft 28 is rotatably supported in the bearing housing via the bearing metal 55 and the bearing holder 56.

The bottom of the bearing holder 56 is a thrust receiving portion 70, in which a thrust receiving portion 71 is disposed. The thrust receiving portion 71 rotatably supports the lower end 28B of the shaft 28. On the other hand, a thrust receiver 72 is provided on the inner surface of the casing 41. The thrust receiver 72 rotatably supports the upper end 28A of the shaft 28. For this,
The upper end 28A and the lower end 28B of the shaft 28 are rotatably held between the inner surface of the casing 41 and the inner surface of the thrust receiving portion 70 via thrust receiving members 72 and 71 without moving in the axial direction.

As the bearing metal 55, for example, a sintered oil-impregnated metal of iron-copper can be used. The bearing holder 56 is made of, for example, brass. The bearing housing 52 is, for example, an aluminum die-cast material.
As shown in FIG. 3, the upper portion has a bearing opening 300. The thrust receivers 71 and 72 are made of plastic having excellent wear resistance, for example, so-called nylon. When the coil 43 is energized by an external control circuit in a predetermined energizing pattern, the interaction between the magnetism generated by the coil 43 and the magnetism generated by the main magnet 30 of the rotor 20 causes the rotor 20 to rotate.
2 continuously rotates about an axis 28. That is, the impeller 31 continuously rotates in the R direction shown in FIG.

The stator yoke 54 has the coil 43, and the stator yoke 54 is fixed to the outer peripheral surface of the bearing holder 56. The coil 43 faces the main magnet 30 of the rotor 20 at a predetermined interval. The casing 41 includes a thrust cover 80 and a cover 52A of the bearing housing 52 described above.
The thrust cover 80 is made of, for example, iron, and the cover 52A of the bearing housing 52 is an aluminum die-cast material as described above. The cover part 52A of the bearing housing 52 has an air introduction hole 100 for taking in air. The side surface of the casing 41 has an air discharge hole 130 for discharging air. The bearing metal 55 is pressed into the inner peripheral surface side of the bearing holder 56, and the bearing holder 56 is
2 is further press-fitted and fixed to the inner peripheral surface. The bearing housing 52 is made of an aluminum die-cast material as described above in consideration of reinforcement of internal parts.

As shown in FIGS. 5 and 6, the stator 22 has a flexible printed circuit board 140, and a control circuit supplies the coil 43 of FIG. Current is supplied. The stator yoke 54 in FIG. 3 is, for example, a stack of a plurality of silicon steel plates and fixed with an adhesive.

Next, an operation example of the motor 10 in the computer 1 will be described. The bearing opening 300 of the bearing 42 in FIGS. 2 and 3 is located on the upper side in the Z direction, and the bearing opening 300 and the impeller 3
1 is located on the upper side. On the other hand, the bearing housing 52 of the bearing 42 and the air introduction hole 100 are located on the lower side in the Z direction. That is, the air introduction hole 100
Is located on the lower side of the main body 3 of the computer 1 in FIG. 1, and the bearing opening 300 is located on the upper side. The air discharge hole 130 is provided on a side surface of the main body 3 in FIG.

By energizing the coil 43 of FIG. 3 from the outside in a predetermined pattern, the magnetic field generated by the coil 43 and the magnetic field generated by the main magnet 30 magnetically interact, and the rotor 20 Axis 2 against
8 rotates continuously. As a result, the impeller 31 continuously rotates in the R direction shown in FIG. 5, so that the impeller 31 moves along the T1 direction in FIGS.
2, the air in the housing 12 shown in FIG. 2 is taken in, and the air is discharged through the casing 41 to the outside of the housing 12 through the air discharge hole 130. Thereby, the heat of the electronic components 92 and the like shown in FIG. 2 which are generated by the operation can be removed and efficiently discharged to the outside of the housing 12.

When the impeller 31 of the motor 10 is rotating as described above, the bearing opening 300 is located on the upper side in the Z direction, and the thrust receiving portion 70 of the bearing housing 52 completely removes the contained lubricating oil. Is contained. Therefore, the bearing opening 3
The oil leakage phenomenon in which the lubricating oil goes outside by its own weight through 00 is eliminated. Therefore, it is possible to completely solve the problem of oil scattering that has conventionally occurred such that the lubricating oil scatters or falls under its own weight in the housing 12 of FIG.

In this case, the rotor 20 is, for example, about 55
Even when rotating at 00 rpm, since the bearing opening 300 is located on the upper side, the lubricating oil does not fall under its own weight from the bearing 42, and the conventional phenomenon that the lubricating oil drips with time is completely eliminated. Can be. Because of this, the lubricating oil in the bearing 42
Since 0% or more can always be ensured, the reliability during rotation of the motor rotor can be sufficiently ensured. Bearing 42, bearing metal 55, which is called a sintered oil-impregnated bearing
Means that lubricating oil is contained in a porous material in a volume ratio of 10 to 3
It can be always used in a so-called self-lubricating state by impregnation of 5%. Further, as shown in FIG. 3, the shaft 28 is rotatably held by the upper thrust receiving member 72 and the lower thrust receiving member 71, so that a magnet magnetic attractive force which has been conventionally required is generated to generate the shaft 28. It is not necessary to devise the movement of the shaft 28 in the axial direction, and a component such as a retaining cover for preventing the shaft 28 from coming off is not required.

FIG. 8 shows another embodiment of the motor of the present invention. The motor 10 shown in FIG. 8 is the same as the motor 10 shown in FIG. 2 and is housed in the housing 12, but the housed position is slightly different. Case 1
2 is a hole 12H on the lower side of the casing 41.
It is formed at a position corresponding to 00. Casing 41
Is connected to the outlet 12R of the housing 12. In the air discharge hole 130 and the discharge port 12R side,
An electronic component 92 that generates heat during operation is arranged. As a result, the impeller 31 rotates continuously, and
Outside air from the housing 12 through the hole 12H from the T0 direction.
And through the air introduction hole 100 along the T1 direction and discharging in the T2 direction through the air discharging hole 130, the discharged air cools the heat-generating electronic component 92 to cool in the T3 direction. Along with the heat.

In the motor of the present invention, since the cup-shaped thrust receiving portion 70 is located on the lower air introduction hole 100 side, the oil of the bearing does not drop due to its own weight, thereby preventing oil scattering. Moreover, since the shaft 28 of the rotor is supported by the thrust receivers 71 and 72, the amount of thrust in the vertical direction of the shaft 28 can be controlled to be constant (for example, about 0.1 mm).
By setting the direction in which the rotor is magnetically attracted by the main magnet to the lower side, the bearing opening can always be located at the upper side, preventing the lubrication oil of the bearing from splashing due to its own weight falling, and reducing the reliability of the bearing. Improvement can be secured.

The motor of the present invention can be used not only as a fan motor but also as a spindle motor used when rotating a disk-shaped information recording medium, for example. The electronic device in this case is not limited to a portable computer, but includes, for example, a thin floppy (registered trademark) disk drive, a thin hard disk drive, and the like. The electronic device may be a device in a field other than a computer, such as a digital camera or a video recorder.

[0032]

As described above, according to the present invention,
Even if the hole for sucking the wind is located on the lower side, the lubricating oil can be prevented from decreasing from the opening of the bearing.

[Brief description of the drawings]

FIG. 1 is an exemplary perspective view showing a portable computer as an example of an electronic apparatus including a motor of the present invention.

FIG. 2 is an exemplary cross-sectional view taken along line AA of the portable computer shown in FIG. 1;

FIG. 3 is an enlarged view showing the structure of the motor shown in FIG. 2;

FIG. 4 is a perspective view conceptually showing the structure of a motor.

FIG. 5 is a plan view showing an impeller and the like of the motor.

FIG. 6 is a plan view showing a stator side of the motor.

FIG. 7 is a side view showing the impeller of the motor.

FIG. 8 is a cross-sectional view showing another embodiment of the present invention.

FIG. 9 is a sectional view showing a conventional motor.

FIG. 10 is a plan view of a conventional motor.

FIG. 11 is a perspective view conceptually showing a conventional motor.

[Explanation of symbols]

1 ... computer (electronic device with motor), 1
0 ... motor, 20 ... rotor, 22 ... stator, 31 ... impeller, 41 ... casing, 4
2 ... bearing, 70 ... thrust receiving part, 71 ...
・ Thrust receiver (second thrust receiver), 72 ...
Thrust receiver (first thrust receiver), 100 ...
Air introduction hole, 130 ... air discharge hole, 300 ... bearing opening

Claims (8)

[Claims] A rotor having a shaft, an impeller rotating with the shaft, a bearing for rotatably supporting the shaft, a stator for rotating the rotor by magnetic interaction, A housing having an air introduction hole for accommodating the stator and introducing air by rotation of the impeller, and a casing having an air discharge hole for discharging the introduced air to the outside, wherein the bearing is an end of the shaft. A thrust receiving portion that rotatably supports the portion and encloses lubricating oil in the bearing, wherein the air introduction hole is provided on the thrust receiving portion side in the casing. . 2. The bearing has a bottom portion and a cylindrical portion integrated with the bottom portion for rotatably supporting the shaft, wherein the bottom portion is the thrust receiving portion, and the shaft is provided via a bearing metal. The motor according to claim 1, wherein the motor is inserted into the cylindrical portion. 3. The rotor is provided with a magnet,
2. The motor according to claim 1, wherein a drive coil is provided on the stator, and when the drive coil is energized, the rotor continuously rotates by a magnetic interaction between the magnet and the drive coil. 3. 4. In a state where the motor is arranged in the electronic device, the air introduction hole and the thrust receiving portion are located below the electronic device, and the impeller is located above the electronic device, 3. The shaft according to claim 2, wherein an upper end of the shaft is rotatably supported by a first thrust receiver of the casing, and a lower end of the shaft is rotatably supported by a second thrust receiver located in the bottom of the bearing. Motor as described. 5. A stator having a shaft, a rotor having an impeller rotating with the shaft, a bearing for rotatably supporting the shaft, and rotating the rotor by magnetic interaction. A casing having an air introduction hole for accommodating the stator and introducing air by rotation of the impeller, and a casing having an air discharge hole for discharging the introduced air to the outside; Wherein the bearing has a thrust receiving portion rotatably supporting an end of the shaft and confining lubricating oil in the bearing, wherein the air introduction hole is provided in the casing so that the thrust An electronic device including a motor, the electronic device being provided on a receiving portion side. 6. The bearing of the motor has a bottom portion for rotatably supporting the shaft, and a cylindrical portion integral with the bottom portion, wherein the bottom portion is the thrust receiving portion, and the shaft is a bearing. An electronic device comprising the motor according to claim 5, which is inserted into the cylindrical portion via a metal. 7. The rotor of the motor is provided with a magnet, and the stator is provided with a drive coil. By energizing the drive coil, a magnetic interaction between the magnet and the drive coil is provided. An electronic apparatus comprising the motor according to claim 5, wherein the rotor rotates continuously. 8. In a state in which the motor is arranged in the electronic device, the air introduction hole and the thrust receiving portion are located below the electronic device, and the impeller is located above the electronic device, 7. The shaft according to claim 6, wherein an upper end of the shaft is rotatably supported by a first thrust receiver of the casing, and a lower end of the shaft is rotatably supported by a second thrust receiver provided in the bottom of the bearing. An electronic device comprising the motor according to claim 1.