JP2003164100A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layout-free fan motor which is of simple configuration and can be assembled only by inserting a shaft into a sleeve. <P>SOLUTION: A motor 1 of a fan motor is provided with a spring 32 which energizes the end of a shaft 11 through a thrust chip 31, and an abutting part 4 which is fitted to the shaft 11 and abuts with the end surface of a sleeve 12. When the shaft 11 is inserted into the sleeve 12, the abutting part 4 elastically deforms while abutting with a surface 220b. When the shaft 11 compresses the spring 32, the abutting part 4 engages with the shaft 11. When the force which inserts the shaft 11 is released, the spring 32 energizes the shaft 11 toward a rotor 21 side, and the abutting part 4 comes away from the surface 220b to abut with the end surface of the sleeve 12. Thus, the fan motor has a simple configuration, and is assembled only by inserting the shaft 11 into the sleeve 12, resulting in layout-free configuration. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor, and more particularly to a layout-free motor.

[0002]

2. Description of the Related Art Conventionally, a fan which is attached to various electronic devices, a disk device for storing information, or the like may use a motor which must be used in a specific direction. For example, in the case of a motor of a type in which the shaft of the bearing mechanism inside the motor is rotatably fitted to and supported by the sleeve and can be easily pulled out, the rotor part may fall off during use or the gap between the rotor part and the stator part There may be a case where a movement restricting means for preventing the displacement of the position is required, or the posture of the motor is limited.

Further, in a motor provided with such a bearing mechanism, the rotation noise becomes large due to the shake of the shaft, which may cause a problem in the information equipment required to reduce the operation noise. Further, in such a motor, in order to configure the movement restricting means, the magnetic center of the magnet of the rotor portion and the electromagnet of the stator portion may be displaced to apply a magnetic biasing force. Noise and magnetic vibrations increase and drive efficiency decreases.

Therefore, as the above-mentioned movement restricting means, Japanese Patent Laid-Open No.
There is proposed a motor in which a structure for preventing the shaft from coming off the sleeve is added, as in JP-A-208457 and JP-A-8-317588.

[0005]

By the way, when a mechanism for preventing slipping out is attached to the shaft as the movement restricting means as in the above publication, a complicated mechanism is attached to a minute portion such as the end of the shaft, and the assembly is performed. The work becomes complicated. Therefore, an object of the present invention is to simplify the structure of a motor that can be used in any posture by providing a mechanism for maintaining the positional relationship between the shaft and the sleeve in a part other than the shaft.

On the other hand, in order to attach such a mechanism to the shaft, in the prior art, an opening for attaching a component is provided in a portion on the stator portion side facing the end portion of the shaft, or a sleeve is fixed to the stator portion. Before inserting the shaft, the shaft is inserted into the sleeve and various parts are attached to the shaft.

However, when the opening is provided in the stator portion, the oil impregnated in the sleeve of the bearing mechanism leaks from the opening or an additional work is required to close the opening. Even if the shaft is inserted into the sleeve in advance, the rotor part with the shaft already attached cannot be used for assembly, and the rotor part needs to be attached to the shaft later, increasing the motor production cost. Resulting in.

In view of the above problems, it is another object of the present invention to provide a motor which can be used in any posture simply by inserting the shaft into the sleeve.

[0009]

According to a first aspect of the present invention, there is provided an electric motor, wherein a shaft, a sleeve for rotatably supporting the shaft, and one end of the shaft are attached. Member, a second member having a recess into which the sleeve is inserted, and a drive mechanism for rotating the first member relative to the second member.
The urging means for urging the other end of the shaft toward the one end side, and the urging means provided on the shaft between the end surface of the sleeve and the bottom surface facing the bottom surface of the recessed portion. And a contact portion that contacts the portion on the second member side.

According to a second aspect of the present invention, in the motor according to the first aspect, the urging means includes a thrust bearing portion in contact with the other end of the shaft, and the thrust bearing portion. And an elastic portion that urges toward the end.

A third aspect of the present invention is the motor according to the second aspect, wherein the other end of the shaft has a convex shape, and a surface of the thrust bearing portion that abuts the other end is the convex shape. It is a concave surface with a larger radius of curvature than the shape.

According to a fourth aspect of the present invention, in the motor according to the second or third aspect, the abutting portion is formed by inserting the other end of the shaft into an insertion opening of the sleeve. A member that is attached to a shaft, and when the shaft is inserted into the sleeve, the other end of the shaft is elastically deformed while the contact portion is in contact with a portion inside the recess, and the other end of the shaft is the insertion opening. And the other end contacts the thrust bearing part to deform the elastic part, the shaft and the contact part are engaged by the restoring force of the contact part, and the shaft is inserted. When the force is released, the contact portion comes into non-contact with the portion inside the recess due to the elastic force of the elastic portion, and contacts the portion on the second member side.

According to a fifth aspect of the present invention, in the motor according to the fourth aspect, the shaft has a groove that engages with the abutting portion along the circumferential direction of the outer surface.

According to a sixth aspect of the invention, there is provided the motor according to the fourth or fifth aspect, wherein the first member is attached to the shaft when the shaft is inserted into the sleeve. Has been.

According to a seventh aspect of the present invention, in the motor according to the sixth aspect, the first member is a member attached to the shaft simultaneously with molding.

The invention according to claim 8 is the motor according to claim 6 or 7, wherein the first member is a member molded together with an impeller.

According to a ninth aspect of the invention, there is provided the motor according to any one of the first to eighth aspects, wherein the contact portion contacts the end surface of the sleeve.

According to a tenth aspect of the present invention, in the motor according to any one of the first to ninth aspects, the contact portion rotates together with the shaft, and the contact surface of the contact portion has a ring shape. Is.

According to an eleventh aspect of the invention, there is provided the motor according to the tenth aspect, wherein fluid is present between the contact portion and the portion on the second member side, and the contact surface and A fluid dynamic pressure groove is formed on at least one of the surfaces facing the contact surface.

[0020]

1 is a view showing the outer appearance of a fan motor 7 according to one embodiment of the present invention. The fan motor 7 is used, for example, for exhausting the inside of various information devices and cooling electronic circuits. The fan motor 7 has a structure in which a plurality of impellers 71 are attached to a rotor portion of an electric motor portion 1, and a stator portion of the motor portion 1 is supported by a flange 72.

FIG. 2 is a vertical cross-sectional view of the motor unit 1 at the position of arrow AA in FIG. In FIG. 2, for convenience of explanation, a direction parallel to the central axis of rotation is shown as the Z direction. The motor unit 1 has a bearing mechanism 10 composed of a shaft 11 and a sleeve 12 at the center, and the shaft 11 is supported by the sleeve 12 so as to be rotatable about an axis facing the Z direction. The sleeve 12 is an oil-impregnated bearing in which a porous material such as a sintered material is impregnated with lubricating oil.

One end of the shaft 11 in the (+ Z) direction is connected to the rotor portion (first member) 21 outside the sleeve 12. The stator portion (second member) 22 has a bottomed cylindrical recess 220 in the center, and the sleeve 12 is inserted into the recess 220. The impeller 71 shown in FIG. 1 is formed outside the outer peripheral surface 211 of the rotor portion 21.
The body of is integrally molded with resin together with the impeller 71. Further, when the main body of the rotor portion 21 is molded, the shaft 11 is simultaneously attached (so-called insert molding), and the rotor portion 21 is prepared as a member to which the shaft 11 is attached. The stator portion 22 is supported by the flange 72 shown in FIG. 1, and the stator portion 22 is fixed by attaching the flange 72 to an information device or the like. When the motor unit 1 is driven, the impeller 71 rotates together with the rotor unit 21 and airflow is generated.

Inside the outer peripheral surface 211 of the rotor portion 21,
A magnet 213 that is magnetized in multiple poles is attached via the yoke 212. On the other hand, in the stator portion 22, the sleeve 1
Around the periphery of 2, a plurality of coils 222, each having a conductor wound around an iron core 221, are provided. The conductor wire is electrically connected to the circuit board 224 below the stator portion 22 via the pin 223 held by the insulating member. Then, by controlling the current passed through the coil 222, the drive mechanism including the magnet 213, the iron core 221, and the coil 222 rotates the rotor portion 21.

The concave portion 220 into which the sleeve 12 is inserted has a surface 22 that abuts the (−Z) side end surface of the sleeve 12.
0b is provided, and between the end surface of the sleeve 12 facing the bottom surface 220a of the recess 220 and the bottom surface 220a,
The contact portion 4 that contacts the end surface of the sleeve 12 has the shaft 11
Attached to.

At the center of the bottom surface 220a of the recess 220, the urging mechanism 3 for urging the (−Z) side end of the shaft 11 toward the (+ Z) side is arranged. The urging mechanism 3 has a thrust tip 31 that functions as a thrust bearing portion that comes into contact with the end portion of the shaft 11, and a spring 32 that is an elastic body that is disposed on the (−Z) side of the thrust tip 31. In the state shown in FIG. 2, the spring 32 is compressed and urges the thrust tip 31 toward the end portion of the shaft 11. Therefore, the shaft 11 is biased toward the (+ Z) side, and the contact portion 4 contacts the end surface of the sleeve 12.

In the motor section 1, since the relative positional relationship between the shaft 11 and the sleeve 12 is made constant by the biasing mechanism 3 and the contact section 4, the magnet 213 is used as in the conventional case.
It is not necessary to position the magnetic center of the electromagnet on the (+ Z) side of the magnetic center of the electromagnet (that is, the iron core 221) and to apply a force in the (-Z) direction to the shaft 11. Therefore, in the motor unit 1 shown in FIG. 2, by matching the magnetic center of the magnet 213 with the magnetic center of the electromagnet, magnetic noise and magnetic vibration are reduced and drive efficiency is increased.

The stator portion 22 into which the sleeve 12 is inserted
A cap 226 for suppressing the scattering or outflow of the lubricating oil to the rotor portion 21 is attached to the upper end of the recess 220. The lubricating oil attached to the inner surface of the cap 226 travels along the inner surface of the cap 226 and returns to the sleeve 12.

3 to 5 are a plan view, a front view and a bottom view of the contact portion 4. The contact portion 4 has a ring shape, and has an insertion opening 41 into which the shaft 11 is inserted, as shown in FIG. A fluid dynamic pressure groove 421 is formed on the contact surface 42 that contacts the end surface of the sleeve 12. The material of the contact portion 4 is metal, for example.

As shown in FIGS. 4 and 5, a substantially cylindrical projecting portion 43 is formed on the bottom surface side of the abutting portion 4, and the projecting portion 43 has a plurality of projections along the extending direction of the insertion opening 41. A cutout 431 is formed. On the inner side surface of the protruding portion 43 (that is, the inner side surface of the insertion opening 41), the convex portion 4 is formed along the circumferential direction.
32 is formed. In the contact portion 4 shown in FIGS. 4 and 5, the four convex portions 432 are separated by the cutout portion 431.

6 to 8 show the shaft 11 and the biasing mechanism 3 when the rotor portion 21 is attached to the stator portion 22.
FIG. 7 is a diagram for explaining the state of the contact portion 4. Figure 6
Shows the state immediately after the shaft 11 is inserted into the sleeve 12 and reaches the contact portion 4, FIG. 7 shows the state at the moment when the contact portion 4 is attached to the end of the shaft 11, and FIG. It shows a state after the contact portion 4 is attached to.

When the rotor portion 21 is attached to the stator portion 22, the spring 32 is previously provided in the central hole of the bottom surface 220a.
Further, the thrust tip 31 is arranged, the contact portion 4 is arranged so as to be placed on the surface 220b, and the sleeve 12 is inserted into the recess 220. The contact portion 4 has a concave portion 220 when the outer surface of the protrusion 43 abuts on a peripheral portion.
Located almost in the center.

As shown in FIG. 6, the shaft 11 has a bottom surface 22.
When pushed toward 0a, the end portion of the shaft 11 is inserted into the insertion opening 41 of the abutting portion 4, and eventually the end portion of the shaft 11 protrudes.
Abut 32. Then, the convex portion 432 is urged so that the end portion of the shaft 11 spreads the insertion opening 41 with the contact portion 4 in contact with the surface 220b. At this time, the contact portion 4 is elastically deformed and the notch portion 431 (see FIG. 4) expands, so that the tip of the shaft 11 is easily inserted into the back of the insertion opening 41.

An annular groove 111 is formed on the outer surface of the end of the shaft 11 along the circumferential direction.
When 1 is inserted further into the interior, the end portion comes into contact with the thrust tip 31 to deform (that is, compress) the spring 32, so that the restoring force of the abutting portion 4 causes a protrusion as shown in FIG. The portion 432 engages the groove 111.

After that, when the force for pushing the shaft 11 into the sleeve 12 is released, as shown in FIG.
The elastic force of 2 causes the shaft 11 toward the end connected to the main body of the rotor portion 21 (that is, (+ (+) in FIG. 8).
(Z) direction), the shaft 11 and the contact portion 4 move in the (+ Z) direction, the contact portion 4 and the surface 220b are brought into a non-contact state, and the contact surface 42 of the contact portion 4 Contacts the end surface of the sleeve 12.

As described above, in the fan motor 7, the shaft 11 and the contact portion 4 are engaged with each other only by inserting the shaft 11 on the rotor portion 21 side into the sleeve 12 on the stator portion 22 side, and the rotor portion 21 is It is prevented from coming off easily (the contact portion 4 functions as a movement restricting means of the rotor portion 21). Further, since the assembly can be performed only by inserting the shaft 11, the rotor portion 21 can be prepared in advance as a component to which the shaft 11 is attached, and after the shaft is inserted, the rotor can be retrofitted or a hole can be formed on the bottom surface of the stator. It is not necessary to separately install a mechanism for preventing the shaft from coming off and sealing the shaft. As a result, the number of steps required for the assembly work can be reduced.

Further, since the shaft 11 is biased toward the main body side of the rotor portion 21 by the spring 32 (that is, the spring 32 moves the (−Z) side end of the shaft 11 to the (+ Z) side end). Therefore, even if the shaft 11 faces an arbitrary direction with respect to gravity, the relative positional relationship of the rotor portion 21 with respect to the stator portion 22 can be appropriately maintained, and the fan motor 7 can be placed in any posture. Use (so-called,
Layout free) is realized.

Further, the shaft 11 and the thrust tip 31
By making the shaft 11 contact with the shaft 11, it is possible to suppress the axial and radial blurring of the shaft 11 and reduce the rotation noise. Therefore, by using the fan motor 7 in the information equipment, the operation noise of the information equipment can be reduced.

Furthermore, since the mechanism for urging the shaft 11 is provided at a portion other than the shaft, the structure of the motor unit 1 can be simplified (or the assembling work can be easily performed).

In addition, it is not necessary to cause the rotor portion 21 to exert a force for pulling it toward the stator portion 22 by shifting the magnetic center of the magnet 213 and the magnetic center of the electromagnet with respect to the direction of the rotation axis as in the conventional case. , The magnet 21 as described above
By making the centers of 3 and the iron core 221 coincide (with respect to the Z direction), magnetic noise and magnetic vibration of the motor unit 1 can be reduced, and drive efficiency can be improved.

On the other hand, when a current is applied to the coil 222 shown in FIG.
Since 11 and the convex portion 432 of the contact portion 4 are strongly engaged with each other, the contact portion 4 rotates together with the shaft 11. Figure 3
As shown in FIG. 5, a fluid dynamic pressure groove 421 is formed on the contact surface 42, and since the oil that is the fluid contained in the sleeve 12 is present between the contact portion 4 and the end surface of the sleeve 12,
When the contact portion 4 rotates together with the rotor portion 21, fluid dynamic pressure is generated by the action of the fluid dynamic pressure groove 421, and the sleeve 12 and the contact portion 4 are brought out of contact with each other. As a result, the rotor portion 21
It is possible to smoothly rotate.

FIG. 9 is a view showing another example of the urging mechanism 3. In the biasing mechanism 3 shown in FIG. 9, the thrust tip 31 has a concave surface 3 in contact with the convex end of the shaft 11.
11 The radius of curvature of the portion of the concave surface 311 that contacts the shaft 11 is made larger than the radius of curvature of the convex shape of the shaft 11. Further, the size of the hole formed on the bottom surface 220 a is larger than that of the thrust tip 31.

In the case of the biasing mechanism 3 shown in FIG. 9, the thrust tip 31 is also movable in the radial direction (radial direction with respect to the central axis of rotation), and the spring 32 further causes the concave surface 311 of the thrust tip 31 and the end of the shaft 11 to move. The contact with the portion makes it possible to properly contact the thrust tip 31 with the tip of the shaft 11. Thereby, the contact state between the thrust tip 31 and the shaft 11 can be stabilized.

FIG. 10 is a view for explaining a mounting method of the contact portion 4 when the surface 220b (see FIG. 8) with which the contact portion 4 contacts is not present in the recess 220.

If the surface 220b does not exist, the recess 220
The bottom 220a of the hole 220 through the stator 22
c is provided. Then, the shaft 11 and the sleeve 12
At the time of inserting the jig 8, the rod-shaped jig 8 is inserted through the hole 220c, and the tip of the jig 8 contacts the contact portion 4. This allows
When the tip of the shaft 11 is inserted into the insertion opening 41 of the contact portion 4, the groove 111 of the shaft 11 and the convex portion 432 of the contact portion 4 are inserted.
And are engaged. That is, the tip of the jig 8 serves as the surface 220b in FIG.

When the contact portion 4 is attached to the shaft 11, the jig 8 is pulled out from the hole 220c and the hole 220c is sealed. By the above work, it is possible to assemble the layout-free fan motor 7 in which the shaft 11 and the contact portion 4 are urged toward the main body side of the rotor portion 21. In this case, a through hole (insertion port 2
20c) is formed, but the size of the hole is sufficiently smaller than that in the case where a mechanism for preventing the shaft from coming off is attached to the shaft from the hole of the stator portion as in the conventional case.
It does not involve the occurrence of oil leakage or the complexity of the hole sealing work.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments and various modifications can be made.

The sleeve 12 in the above embodiment is not limited to the oil-impregnated bearing, but may be a fluid dynamic pressure bearing. Further, as the bearing member for the thrust direction, a fluid dynamic bearing may be used instead of the thrust tip 31.

Although the fluid dynamic pressure groove 421 is formed in the contact portion 4 in the above-described embodiment, the fluid dynamic pressure groove 421 is formed in the contact surface 42.
It may be formed on the end surface of the sleeve 12 which faces to, or on both surfaces. Further, the contact portion 4 does not have to be attached so as to rotate completely with the shaft 11, and the end face of the sleeve 12 and the contact portion 4 are lubricated without using the fluid dynamic pressure groove 421. You may just Note that the end surface of the sleeve 12 and the contact portion 4 may be in a non-contact state or a contact state as long as they substantially abut each other during rotation. The contact portion 4 does not have to be ring-shaped as in the above embodiment, but when the contact portion 4 rotates, it is preferably ring-shaped in order to smoothly rotate.

Further, the abutting portion 4 may abut on a portion on the side of the stator portion 22 other than the end surface of the sleeve 12. For example, another member may be arranged below the end surface of the sleeve 12, and the portion in the recess 220 and the contact portion 4 may contact each other. Of course, considering that a large amount of oil is present in the sleeve 12, it can be said that the contact portion 4 preferably contacts the end surface of the sleeve 12.

Thrust tip 3 in the above embodiment
1 is movable in the Z direction, but if the shaft 11 becomes unstable due to rotation in the circumferential direction, the thrust tip 3
The thrust chip 31 may be movable only in the Z direction by providing unevenness extending in the Z direction on the 1 and the fitting portion on the side of the stator portion 22.

Although the contact portion 4 is one member in the above embodiment, the contact portion 4 may be composed of a plurality of members. For example, the part of the contact surface 42 and the part of the protrusion 43 may be separate members.

The surface 220b in the above embodiment may be provided at a portion protruding from the side surface of the recess 220,
It may be provided at a portion protruding from the bottom surface. That is,
The contact portion 4 when the shaft 11 is inserted into the sleeve 12
By abutting a predetermined portion in the recess 220,
The attachment of the contact portion 4 to the shaft 11 is realized.

Instead of the coiled spring 32, another type of elastic body may be used. For example, rubber or a leaf spring may be used. Thrust tip 3 which is the thrust bearing
A biasing mechanism 3 in which 1 and a spring 32, which is an elastic body, are integrated
May be For example, even if a leaf spring is brought into contact with the end portion of the shaft 11, the abutting portion of the leaf spring acts as a thrust bearing portion, and the entire leaf spring acts as an elastic body that biases the abutting portion. Good. Of course, in a motor in which a thrust bearing such as a thrust tip is conventionally provided as a separate member, it is preferable in terms of design that the thrust bearing member and the elastic body are provided separately.

In the drawings referred to in the above embodiment, the width of the groove 111 in the central axis direction (Z direction) is wider than the width of the convex portion 432, but the width of the groove 111 is the width of the convex portion 432. May be equal to or may be narrow.

In the above embodiment, the convex portion 432 is the insertion port 4
Although it is formed along the inner side surface of No. 1, it may be formed only on a part of the inner side surface. For example, a plurality of spherical convex portions may be formed as the convex portion 432. Groove 111 is also shaft 11
It does not need to be continuously formed along the outer side surface of, and may be formed only partially. The cross-sectional shapes of the convex portion 432 and the groove 111 may be changed as appropriate.

Since the outer surface of the shaft 11 is usually cylindrical, it is preferable that the inner surface of the insertion opening 41 is also cylindrical. It can be said that the portion 432 and the groove 111 are preferably formed in an annular shape along the circumferential direction of the cylindrical surface.

The recess 220 may be formed by attaching a lid to a cylindrical hole. Of course, when the main body of the stator portion 22 is integrally molded, the recess 22
It is preferable that the 0 side surface and the bottom surface 220a are integrally molded. By integrally forming the recess 220 in the main body of the stator portion 22, oil leakage from the back surface of the stator portion 22 is completely prevented, and in addition, the thrust tip 31 and the spring 32 can be attached with high accuracy. It

The attachment of the shaft 11 to the rotor portion 21 is not limited to so-called insert molding, which is attached simultaneously with the molding of the main body of the rotor portion 21. For example, the shaft 11 may be attached to the rotor portion 21 by press fitting or adhesion.

The mechanism of the motor unit 1 is not limited to use as a fan, but can be used in a disk device such as a compact disk or a hard disk for reading information. As a result, the operation efficiency of the disk device is improved, the operation noise is reduced, and the layout is free.

In the above embodiment, the shaft 11 rotates within the sleeve 12, but the shaft may be fixed and the sleeve may rotate. That is, the member to which the shaft is attached and the member to which the sleeve is attached may rotate relatively. In the drive mechanism including the magnet and the electromagnet, the magnet may be provided in the stator part and the electromagnet may be provided in the rotor part.

In the motor unit 1 in the above embodiment, the magnet 213 having an annular multi-pole magnetism is used, but the magnet 213 may of course be composed of a plurality of magnets.
On the contrary, the electromagnet on the side of the stator portion 22 is not limited to the form that can be regarded as a plurality of electromagnets, and may be one electromagnet capable of generating a plurality of magnetic poles.

Further, as shown in FIG. 11, the surface of the groove 111 and the convex portion 432 on the side of the thrust tip 31 may be a surface perpendicular to the rotation axis. With this, even if a force is applied in the direction in which the shaft 11 comes off, the surfaces perpendicular to the rotation axis are in contact with each other, and the shaft 11 can be reliably prevented from coming off. Even with the shape shown in FIG. 11, workability in attaching the contact portion 4 to the shaft 11 is not impaired.

[0063]

According to the invention of claims 1 to 11, it is possible to simplify the structure of the motor that can be used in any posture.

According to the third aspect of the present invention, the contact state between the thrust bearing portion and the shaft can be stabilized.

In the invention of claim 4, the motor can be assembled only by inserting the shaft into the sleeve.

Further, according to the invention of claim 5, the contact portion can be firmly attached to the shaft.

Further, in the inventions of claims 6 to 8, even when the shaft is previously attached to the first member, the shaft can be easily attached to the second member side.

In the eleventh aspect of the invention, it is possible to smoothly rotate the shaft.

[Brief description of drawings]

FIG. 1 is a diagram showing an appearance of a fan motor.

FIG. 2 is a vertical sectional view of a motor unit.

FIG. 3 is a plan view of a contact portion.

FIG. 4 is a front view of a contact portion.

FIG. 5 is a bottom view of the contact portion.

FIG. 6 is a diagram for explaining a state of a shaft, a biasing mechanism, and an abutting portion when the rotor portion is attached to the stator portion.

FIG. 7 is a diagram for explaining a state of a shaft, a biasing mechanism, and an abutting portion when the rotor portion is attached to the stator portion.

FIG. 8 is a diagram for explaining a state of a shaft, a biasing mechanism, and an abutting portion when the rotor portion is attached to the stator portion.

FIG. 9 is a diagram showing another example of the biasing mechanism.

FIG. 10 is a diagram for explaining another attachment method of the contact portion.

FIG. 11 is a view showing another shape of the groove and the convex portion.

[Explanation of symbols]

1 Motor part 3 urging mechanism 4 abutment 11 shaft 12 sleeves 21 rotor 22 Stator part 31 thrust tip 32 spring 41 insertion slot 42 Contact surface 71 Impeller 111 groove 213 magnet 220 recess 220a bottom 220b side 221 iron core 222 coil 311 concave 421 Fluid dynamic pressure groove

Continued front page    F-term (reference) 3J011 AA03 AA07 BA04 BA10 CA02                       JA02 KA02 KA03 LA01 LA05                       PA02 SB19                 5H605 AA05 AA08 BB05 BB19 CC04                       DD09 EB02 EB06 EB18 EB19                       EB37                 5H607 AA04 BB01 BB14 BB17 CC03                       FF04 GG02 GG03 GG09

Claims (11)

[Claims] 1. An electric motor, comprising: a shaft, a sleeve that rotatably supports the shaft, a first member to which one end of the shaft is attached, and a recess into which the sleeve is inserted. A second member; a drive mechanism that rotates the first member relative to the second member; an urging unit that urges the other end of the shaft toward the one end side; A contact portion provided on the shaft between an end surface of the sleeve facing the bottom surface of the sleeve and the bottom surface, and abutting against the portion on the second member side by the action of the biasing means. And a motor. 2. The motor according to claim 1, wherein the urging means urges the thrust bearing portion in contact with the other end of the shaft and the thrust bearing portion toward the other end. A motor having an elastic portion. 3. The motor according to claim 2, wherein the other end of the shaft has a convex shape, and a surface of the thrust bearing portion in contact with the other end has a larger radius of curvature than the convex shape. A motor having a concave surface. 4. The motor according to claim 2, wherein the contact portion is a member attached to the shaft by inserting the other end of the shaft into an insertion opening of the sleeve. When the shaft is inserted into the sleeve, the other end of the shaft is inserted into the insertion opening while being elastically deformed in a state where the abutting part is in contact with a portion inside the recess, and the other end When the shaft comes into contact with the thrust bearing portion and deforms the elastic portion, the shaft and the contact portion are engaged by the restoring force of the contact portion, and the force for inserting the shaft is released. A motor characterized in that the abutting portion is brought into non-contact with a portion inside the concave portion by the elastic force of the elastic portion and abuts against a portion on the second member side. 5. The motor according to claim 4, wherein the shaft has a groove that engages with the contact portion along a circumferential direction of an outer side surface. 6. The motor according to claim 4, wherein the first member is attached to the shaft when the shaft is inserted into the sleeve. The motor to drive. 7. The motor according to claim 6, wherein the first member is a member attached to the shaft simultaneously with molding. 8. The motor according to claim 6, wherein the first member is a member that is molded together with an impeller. 9. The motor according to claim 1, wherein the contact portion contacts the end surface of the sleeve. 10. The motor according to claim 1, wherein the contact portion rotates together with the shaft, and the contact surface of the contact portion has a ring shape. motor. 11. The motor according to claim 10, wherein a fluid is present between the contact portion and the portion on the side of the second member and faces the contact surface and the contact surface. A motor having a fluid dynamic pressure groove formed on at least one of the surfaces.