JP2003164101A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layout-free motor with simple structure capable of being assembled by only inserting a shaft in a sleeve. <P>SOLUTION: A motor section 1 of a fan motor is provided with a spring 32 that energizes the sleeve 12 and an abutting part 4 that is mounted to the shaft 11 and abuts on the end face of the sleeve 12. When the shaft 11 is inserted, the abutting part 4 is elastically deformed while abutting on a plane 220b and fixed to the shaft 11 when the shaft 11 abuts on a thrust chip 225. At this time, the abutting part 4 is moved to the sleeve 12 side by a restoring force and brought into non-contact with the plane 220b. The shaft 11 is energized by the spring 32 via the sleeve 12 and the abut part 4 and abuts on the thrust chip 225. By such a configuration, the fan motor can be assembled by only inserting the shaft 11 in the sleeve 12 with simple structure, thus making the fan motor layout-free. <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 movable in the thrust direction, and a drive mechanism for rotating the first member relative to the second member. An urging means for urging the sleeve toward the bottom surface of the recess, and the shaft provided between the bottom surface and the end surface of the sleeve facing the bottom surface of the recess, and the urging means. And a contact portion that contacts the sleeve-side portion.

According to a second aspect of the present invention, in the motor according to the first aspect, the urging means is provided between the other end surface of the sleeve and the portion on the second member side. Elastic member.

According to a third aspect of the present invention, there is provided the motor according to the first or second aspect, wherein the motor is located on the other end face side of the sleeve and is fixed to the second member. Further provided with three sleeves.

The invention according to claim 4 is the motor according to claim 3, wherein the length of the sleeve is shorter than the length of the other sleeve in the thrust direction.

According to a fifth aspect of the invention, there is provided the motor according to any one of the first to fourth aspects, wherein the abutting portion is
A member that is attached to the shaft by inserting the other end of the shaft into the insertion opening, and is in a state in which the contact portion is in contact with a portion inside the recess when the shaft is inserted into the sleeve. The other end of the shaft is inserted into the insertion opening while being elastically deformed by, and at the stage where the other end contacts the bottom surface of the recess, the contact portion moves to the side opposite to the bottom surface due to the restoring force. The shaft and the abutting portion are engaged with each other in a state where the abutting portion and the portion inside the recess are not in contact with each other.

According to a sixth aspect of the present invention, in the motor according to the fifth aspect, one of the outer surface of the shaft and the inner surface of the insertion port has a convex portion, and the other surface has a convex portion. The surface has an inclined surface, and when the other end of the shaft is inserted into the insertion opening, the convex portion and the inclined surface bias each other at a stage where the other end contacts the bottom surface. By moving the convex portion along the inclined surface, the contact portion and the portion inside the concave portion are brought into non-contact with each other.

According to a seventh aspect of the present invention, in the motor according to the sixth aspect, both the one surface and the other surface are cylindrical surfaces, and the convex portion is the one surface. Is a ring-shaped convex portion formed along the other surface, and the inclined surface is a part of the ring-shaped groove formed along the other surface.

The invention according to claim 8 is the motor according to claim 6 or 7, wherein the first member is attached to the shaft when the shaft is inserted into the sleeve. .

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

The invention described in claim 10 is the motor according to claim 8 or 9, wherein the first member is a member molded together with an impeller.

An eleventh aspect of the invention is the motor according to any one of the first to tenth aspects, wherein the contact portion rotates together with the shaft, and the contact portion is ring-shaped.

According to a twelfth aspect of the present invention, in the motor according to the eleventh aspect, fluid is present between the contact portion and the portion on the second member side, and A fluid dynamic pressure groove is formed on at least one of the contact surface and the surface facing the contact surface.

[0021]

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 section 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 facing 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. The thrust tip 22 with which the (−Z) side end of the shaft 11 abuts on the center of the bottom surface 220a.
5 are arranged.

A 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.

The sleeve 12 is in the thrust direction (Z in FIG. 2).
Direction) and is inserted into the recess 220.
A fixing member 31 is attached between the sleeve 12 and the cap 226 along the inner surface of the recess 220, and a plurality of springs 32 are arranged between the fixing member 31 and the end face of the sleeve 12 on the cap 226 side. . The fixing member 31 and the spring 32 configure a biasing mechanism 3 that biases the sleeve 12 toward the bottom surface 220a of the recess 220. Then, by urging the sleeve 12 toward the bottom surface 220 a, the shaft 11 is urged toward the thrust tip 225 via the contact portion 4.

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 different from the conventional one.
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 contact portion 4 is made of metal, for example.

FIG. 3 is a view showing a cross section of the recess 220 and the sleeve 12 taken along a plane perpendicular to the Z direction shown in FIG. On the inner side surface of the recess 220 and the outer side surface of the sleeve 12, concaves and convexes that fit with each other are formed along the moving direction of the sleeve 12 (that is, the Z direction). Therefore,
The sleeve 12 moves in the thrust direction, but the shaft 1
It does not rotate with 1.

4 to 6 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.

As shown in FIGS. 5 and 6, 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 43 along the direction in which the insertion opening 41 extends. A cutout 431 is formed. An annular convex portion 432 is formed on the inner side surface of the protruding portion 43 (that is, the inner side surface of the insertion opening 41) along the circumferential direction. Note that in the contact portion 4 shown in FIGS. 5 and 6, the four convex portions 432 are separated by the cutout portions 431.

7 to 9 show the shaft 11 and the sleeve 1 when the rotor portion 21 is attached to the stator portion 22.
FIG. 2 is a diagram for explaining the states of the biasing mechanism 3, and the contact portion 4. 7 shows a state immediately after the shaft 11 is inserted into the sleeve 12 and reaches the contact portion 4, FIG. 8 shows a state where the end portion of the shaft 11 is being attached to the contact portion 4, and FIG. The state where the contact portion 4 is attached to the shaft 11 is shown.

When the rotor portion 21 is attached to the stator portion 22, the contact portion 4, the sleeve 12 and the spring 32 are arranged in advance in the concave portion 220 of the stator portion 22, and the fixing member 31 is fixed to the inner surface of the concave portion 220. To be done. The spring 32 may or may not be compressed before the shaft 11 is inserted. The contact portion 4 is positioned substantially at the center of the recess 220 by the outer surface of the protruding portion 43 contacting the peripheral portion.

When the shaft 11 is pushed toward the bottom surface 220a, the end portion of the shaft 11 is inserted into the insertion port 41 of the contact portion 4, and eventually the end portion contacts the convex portion 432.
At this time, in the present embodiment, the sleeve 12 is (-Z).
The surface 220b of the recess 220 and the contact portion 4
, But need not be sandwiched. After that, as shown in FIG. 8, the end portion of the shaft 11 biases the convex portion 432. At this time, the contact portion 4 is elastically deformed and the notch 431 is formed.
By expanding (see FIG. 5), 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 further inserted into the inner side of the insertion opening 41, the tip of the convex portion 432 comes to the edge of the groove 111 when the end of the shaft 11 comes into contact with the bottom surface 220a (more precisely, the thrust tip 225 of the bottom surface). 9 is reached by the restoring force of the contact portion 4.
As shown in, the convex portion 432 moves to approximately the center of the groove 111. As a result, the contact portion 4 moves to the side opposite to the bottom surface 220a, and the shaft 11 and the contact portion 4 engage with each other with the contact portion 4 and the surface 220b not in contact with each other.

Further, the spring 32 is compressed by the movement of the contact portion 4, and the spring 32 exerts a force on the fixing member 31 and the sleeve 12 in a direction away from each other,
The sleeve 12, the contact portion 4 and the shaft 11 have a bottom surface 22.
It is urged to the 0a side. As a result, the shaft 11 comes into contact with the thrust tip 225 in a biased state.

FIG. 10 is a view for explaining in more detail the principle by which the relationship between the shaft 11 and the contact portion 4 shifts from the state shown in FIG. 8 to the state shown in FIG.

Below the groove 111 (on the tip side of the shaft 11)
Is an inclined surface 111 a inclined with respect to the biasing direction of the convex portion 432 (direction perpendicular to the central axis of the shaft 11). When the convex portion 432 reaches the groove 111, the convex portion 432 and the inclined surface 111 a. And will urge each other. Since the inclined surface 111a is inclined toward the center of the groove 111 so as to approach the central axis of the shaft 11, the convex portion 432 is formed along the inclined surface 111a as indicated by an arrow 432a.
Move to the center of 11. As a result, the contact portion 4 moves to the sleeve 12 side and the contact portion 4 and the surface 220b are brought into a non-contact state.

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. 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 bottom surface 220a by the spring 32 via the sleeve 12 and the abutting portion 4, even if the shaft 11 is oriented in an arbitrary direction with respect to gravity, it is against the stator portion 22. The relative positional relationship of the rotor portion 21 can be appropriately maintained, and the fan motor 7 can be used in any posture (so-called layout-free).

Further, the shaft 11 is replaced with the thrust tip 22.
By abutting against the shaft 5, or by minimizing the clearance between the shaft 11 and the thrust tip 225, the axial and radial deviation of the shaft 11 can be suppressed, and the rotation noise can be reduced.
Therefore, by using the fan motor 7 in the information equipment, the operation noise of the information equipment can be reduced. In FIG. 2, the shaft 11 and the thrust tip 225 may be separated from each other when gravity acts in the (+ Z) direction, and the contact portion 4 is supported by the end surface of the sleeve 12 while receiving the weight of the rotor portion 21. As a result, it is possible to suppress the shake of the shaft 11 in the axial direction and the radial direction.

Further, 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 flows through the coil 222 shown in FIG. 2 and the rotor portion 21 rotates, the groove 1 of the shaft 11
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 4
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. 11 is a view for explaining a mounting method of the contact portion 4 when the surface 220b (see FIG. 9) 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. When the shaft 11 is inserted into the sleeve 12, the rod-shaped jig 8 is inserted through the hole 220c, and the tip of the jig 8 abuts the abutting portion 4, whereby the spring 32 is compressed. Then, the shaft 1 is inserted into the insertion opening 41 of the contact portion 4.
The groove 1 of the shaft 11 is inserted by inserting the tip of the shaft 1.
11 and the convex portion 432 of the contact portion 4 are engaged with each other.

When the contact portion 4 is attached to the shaft 11, the jig 8 is pulled out from the hole 220c. As a result, the sleeve 12, the contact portion 4, and the shaft 11 are urged by the spring 32, and the shaft 11 moves toward the thrust tip 2
Abuts 25. After that, 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 biased toward the thrust tip 225 side. In this case, a through hole (hole 220c) is formed in the stator portion 22, but the size of the hole is larger than that in the case where a conventional mechanism for preventing the shaft from coming off is attached from the hole of the stator portion. It is sufficiently small, and does not cause oil leakage or complicated hole sealing work.

FIG. 12 is a view showing another example of the urging mechanism 3. In the biasing mechanism 3 shown in FIG. 12, another sleeve 31a is fixed to the (+ Z) side of the sleeve 12 (that is, the end surface side opposite to the bottom surface 220a), and the spring 32 is provided between the sleeve 12 and the sleeve 31a. Are placed.
That is, the biasing mechanism 3 shown in FIG. 12 has a structure in which the fixing member 31 in FIG. 2 is replaced with the sleeve 31a.

In the case of the urging mechanism 3 shown in FIG. 12, the manner in which the rotor portion 21 is attached to the stator portion 22 is the same as in FIGS. 7 to 9. That is, when the shaft 11 is inserted into the sleeve 31a and the sleeve 12, the contact portion 4 is elastically deformed and the groove 111 of the shaft 11 is engaged with the convex portion 432 of the contact portion 4. At this time, By moving 4 to the sleeve 12 side, the spring 32 is compressed and the contact portion 4 is not in contact with the surface 220b. As a result, it is possible to assemble a layout-free motor simply by inserting the shaft 11.

By providing the two sleeves 31a and 12, the sleeve 31a fixed to the stator portion 22 side.
It is possible to stably support the shaft 11. The lengths of the two sleeves 31a and 12 in the Z direction (that is, the thrust direction) may be set arbitrarily, but preferably, the length of the sleeve 12 is longer than that of the other sleeve 31a as shown in FIG. Shorter than that. Sleeve 3
1a mainly plays a role of stably supporting the shaft 11, and the sleeve 12 mainly plays a role of urging the abutting portion 4 and the shaft 11.
By making the length shorter than that of the sleeve 31a, it is possible to further stabilize the support and rotation of the shaft 11.

In FIG. 12, the two sleeves 31a,
Although the spring 32 is arranged between the two 12, a fixing member 31 that supports the spring 32 may be separately provided.

FIG. 13 is a view showing another shape of the convex portion 432 and the groove 111. In FIG. 9, the width of the convex portion 432 in the central axis direction (Z direction in FIG. 2) is made smaller than the width of the groove 111 in the central axial direction, but in the example shown in FIG.
The width of 32 is larger than the width of the groove 111. In the case of the example shown in FIG. 13, when the shaft 11 is inserted and the convex portion 432 approaches the groove 111, the restoring force of the contact portion 4 causes the surface of the lower side (bottom surface 220a side) of the convex portion 432 and the groove 111. The lower edge urges each other, and the lower edge of the groove 111 relatively moves along the lower surface of the convex portion 432.
As a result, the contact portion 4 moves to the sleeve 12 side, and the contact portion 4 engages with the shaft 11 in a state where the contact portion 4 and the surface 220b are not in contact with each other.

That is, in the case of the example shown in FIG.
The lower surface of 32 serves as an inclined surface in the description of FIG. 10, and the lower edge of the groove 111 serves as a convex portion with respect to the inclined surface. In this way, the insertion port 41
Is formed on the inner side surface of the shaft 11 and a convex portion is formed on the outer side surface of the shaft 11 so as to contact the inclined surface. When the end portion of the shaft 11 contacts the bottom surface 220a, the convex portion and the inclined surface urge each other. Alternatively, the convex portions may move along the inclined surface.

The width of the convex portion 432 may be equal to the width of the groove 111. That is, the convex portion and the inclined surface that urge each other are respectively the shaft 11 and the contact portion 4.
It is not necessary to clearly know in which of these areas it is provided.

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 in the thrust direction, a fluid dynamic bearing may be used instead of the thrust tip 225.

In the above-described embodiment, the fluid dynamic pressure groove 421 is formed in the contact portion 4, but the fluid dynamic pressure groove 421 does not contact 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 sleeve 12 side other than the end surface of the sleeve 12. For example,
Another member may be arranged below the end surface of the sleeve 12. 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.

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-described 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.

In the biasing mechanism 3, an elastic body of another type may be used instead of the spring 32. For example, rubber or a leaf spring may be used. The fixing member 31 and the spring 32, which is an elastic body, may be integrated into the urging mechanism 3.
For example, a leaf spring that inclines and projects toward the bottom surface 220a is fixed to the inner surface of the recess 220, and the tip of the leaf spring is attached to the sleeve 12.
You may make it contact with the end surface of. In this case, the vicinity of the fixed portion of the leaf spring serves as the fixing member 31, and the entire leaf spring serves as an elastic body that biases the contact portion.
Further, the fixing member 31 may be integrated with the cap 226. If the elastic body is provided between the end surface of the sleeve 12 on the rotor portion 21 side and the portion on the stator portion 22 side to urge the sleeve 12, the urging mechanism 3 may be provided in any way. Good.

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 side surface of the shaft 11 is usually cylindrical, it is preferable that the inner side 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, it is possible to completely prevent oil from leaking from the back surface of the stator portion 22. Further, by integrally forming the stator portion 22, even when the thrust tip 225 is separately attached, the thrust tip 225 can be attached accurately.

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 multipole 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. 14, the surface of the groove 111 and the convex portion 432 on the side of the thrust tip 225 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. 14, workability in attaching the contact portion 4 to the shaft 11 is not impaired.

[0070]

According to the inventions of claims 1 to 12, the structure of the motor that can be used in any posture can be simplified.

Further, according to the inventions of claims 3 and 4, it is possible to stabilize the support of the shaft.

In the inventions of claims 5 and 6, the motor can be assembled only by inserting the shaft into the sleeve.

According to the invention of claim 7, the contact portion can be firmly attached to the shaft.

Further, according to the invention of claims 8 to 10, even when the shaft is previously attached to the first member, the shaft can be easily attached to the second member side.

According to the twelfth 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 view showing a cross section of a recess and a sleeve.

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

FIG. 5 is a front view of a contact portion.

FIG. 6 is a bottom view of the contact 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 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. 10 is a view for explaining the principle of attaching the contact portion to the shaft.

FIG. 11 is a diagram for explaining another attachment method of the contact portion.

FIG. 12 is a view showing another example of the biasing mechanism.

FIG. 13 is a diagram showing another example of the contact portion and the groove.

FIG. 14 is a diagram showing another shape of a groove and a convex portion.

[Explanation of symbols]

1 Motor part 3 urging mechanism 4 abutment 11 shaft 12 sleeves 21 rotor 22 Stator part 31 fixing member 31a sleeve 32 spring 41 insertion slot 42 Contact surface 71 Impeller 111 groove 111a inclined surface 213 magnet 220 recess 220a bottom 220b side 221 iron core 222 coil 421 Fluid dynamic pressure groove 432 convex

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3J011 AA03 AA07 BA04 CA02 JA02                       KA02 KA03 LA01 LA05 SB19                 3J012 AB02 AB20 BB01 BB02 CB03                       DB07 DB14 FB01                 5H605 AA05 AA08 BB05 BB19 CC04                       DD09 EB02 EB06 EB18 EB19                       EB37                 5H607 AA04 BB01 BB14 BB17 CC03                       FF04 GG02 GG03 GG09

Claims (12)

[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 the sleeve that is movable in a thrust direction. Second member having a recess inserted in a state, a drive mechanism for rotating the first member relative to the second member, and urging the sleeve toward the bottom surface of the recess. Urging means, an abutting portion provided on the shaft between the bottom surface and the bottom surface of the sleeve facing the bottom surface of the recess, and abutting against the sleeve side portion by the action of the urging means, A motor comprising: 2. The motor according to claim 1, wherein the urging means is an elastic member provided between the other end surface of the sleeve and a portion on the second member side. A motor characterized by. 3. The motor according to claim 1, further comprising: another sleeve that is located on the other end surface side of the sleeve and that is fixed to the second member. Characteristic motor. 4. The motor according to claim 3, wherein a length of the sleeve in the thrust direction is equal to the length of the sleeve.
A motor characterized by being shorter than the length of one sleeve. 5. The motor according to claim 1, wherein the abutting portion is a member attached to the shaft by inserting the other end of the shaft into an insertion opening, When the shaft is inserted into the sleeve, the other end of the shaft is inserted into the insertion port while elastically deforming in a state in which the abutting part is in contact with a portion inside the recess, and the other end is At the stage of contacting the bottom surface of the recess, the contact portion moves to the side opposite to the bottom surface due to the restoring force, and the shaft and the contact portion are in contact with each other in a state where the contact portion and the portion inside the recess are not in contact with each other. A motor which is engaged with a contact portion. 6. The motor according to claim 5, wherein one of the outer surface of the shaft and the inner surface of the insertion port has a convex portion, and the other surface has an inclined surface. When the other end of the shaft is inserted into the insertion opening, the convex portion and the inclined surface bias each other at a stage where the other end contacts the bottom surface, and the convex portion is inclined. A motor that is characterized in that the contact portion and the portion in the recess are brought into non-contact with each other by moving along the surface. 7. The motor according to claim 6, wherein both of the one surface and the other surface are cylindrical surfaces, and the convex portion is a circle formed along the one surface. A motor having an annular convex portion, wherein the inclined surface is a part of an annular groove formed along the other surface. 8. The motor according to claim 6 or 7, wherein the first member is attached to the shaft when the shaft is inserted into the sleeve. 9. The motor according to claim 8, wherein the first member is a member attached to the shaft simultaneously with molding. 10. The motor according to claim 8 or 9, wherein the first member is a member molded together with an impeller. 11. The motor according to claim 1, wherein the contact portion rotates together with the shaft, and the contact portion has a ring shape. 12. The motor according to claim 11, wherein fluid is present between the contact portion and the portion on the second member side, and the contact surface of the contact portion and the contact surface A motor, wherein a fluid dynamic pressure groove is formed on at least one of the surfaces facing the surface.