JP2000230554A - Fluid bearing mechanism and motor loaded with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To return oil to a rotary shaft support part, without scattering the oil outside of the motor by providing an oil sealing part having a spiral groove in an opposite arrangement surface, and forming the spiral groove so that the oil leaking to a clearance is moved to the rotary shaft support part with the rotation of a rotor. SOLUTION: A radial scraping member 13 is provided with a spiral groove formed, so that the oil leaked to a clearance (an open end clearance 40) between a base 3 is moved to a radial bearing 7a side with the rotation of a hub 1. Furthermore, the radial scraping member 13 is fixed to the hub 1, so that the spiral groove thereof is arranged on a flat surface in the direction at right angles with respect to a rotary shaft 2. With this structure, even in the case where the oil leaks from the nearing clearance by vibration and impact, the radial scraping member 13 can move the leaked oil in a direction for sealing again and return the leaked oil to the bearing clearance, without scattering the oil outside of a motor with rotation of the hub 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid bearing mechanism for supporting a rotor by utilizing oil dynamic pressure, and a motor equipped with the fluid bearing mechanism, particularly used in digital technology fields including information equipment and video equipment. The present invention relates to a motor built in an electric device to be used.

[0002]

2. Description of the Related Art In recent years, in the field of digital technology, there has been a strong demand for higher recording density of information (data) and high-speed data transfer. In response to such demands, in information equipment and video equipment including a hard disk device and a recording / reproducing device, it is necessary to improve the rotation accuracy of a built-in motor for rotationally driving a disk-shaped or tape-shaped recording medium. High speed rotation is required. As a motor that can simultaneously satisfy these requirements, a motor equipped with a fluid bearing mechanism that generates a dynamic oil pressure and supports the rotating body has been developed and put into practical use.

[0003] Hereinafter, a conventional hydrodynamic bearing mechanism and a conventional motor equipped with the same will be specifically described with reference to FIG. In the following description, a motor built in a hard disk device will be described as an example. FIG. 23 is a cross-sectional view illustrating a configuration of a conventional fluid bearing mechanism and a conventional motor. In FIG. 23, the conventional hydrodynamic bearing mechanism fills an oil (not shown) into a rotating shaft 52 that rotates in one direction and a predetermined gap formed between the rotating shaft 52 and the rotating shaft 52. A rotating shaft support for supporting the rotating shaft 52,
And a rotor that rotates integrally with the rotation shaft 52. The rotor includes a hub 51, a magnet 55, a yoke 5
6 and a thrust flange 58.
The hub 51 has a disk-shaped recording medium (not shown) mounted thereon, is pressed into one end of the rotating shaft 52, and rotates together in one direction. A yoke 56 made of a soft magnetic material and a magnet 55 are adhered on the inner peripheral surface of the hub 51. The inner peripheral cylindrical surface of the magnet 55 has a plurality of N poles and S poles.
The poles are alternately magnetized. Further, a thrust flange 58 is fixed to the other end of the rotating shaft 52 with a screw 60 and is formed integrally with the rotating shaft 52.

[0004] The rotary shaft support is provided with a rotary shaft 5 in the radial direction.
2 and a thrust bearing means for supporting the rotary shaft 52 in the thrust direction. More specifically, radial bearings 57a and 57b having a diameter several μm larger than the diameter of the rotating shaft 52 are formed on the base 53 of the rotating shaft support along the direction of the rotating shaft. Therefore, the rotating shaft 52 and each radial bearing 57
A bearing gap having a predetermined gap in the unit of several μm is formed between the bearing gaps a and 57b. Radial bearing 57
A plurality of wedge-shaped grooves (not shown) for generating dynamic pressure are provided on the inner peripheral cylindrical surfaces of a and 57b by a rolling method. Oil that generates dynamic pressure is injected into these wedge-shaped grooves. As a result, the bearing gap is filled with oil, and radial bearing means is formed.

[0005] A thrust plate 59 is opposed to the thrust flange 58. The thrust plate 59 is fixed to the open end of the base 53 by press-fitting. A plurality of spiral grooves (not shown) for generating dynamic pressure are formed on the lower surface of the thrust flange 58 or the upper surface of the thrust plate 59 by an etching method or a coining method. Oil that generates dynamic pressure is injected into these spiral grooves. This allows
Oil is filled in a bearing gap formed between the lower surface of the thrust flange 58 and the upper surface of the thrust plate 59 to constitute thrust bearing means. In the motor equipped with the above-mentioned conventional fluid bearing mechanism, a stator core 61 and a multi-phase stator coil 54 are provided on an outer peripheral cylindrical surface of a base 53 in order to rotate the above-described rotating shaft 52 and a rotor. I have. The stator core 61 is adhered and fixed on the outer peripheral cylindrical surface of the base 53. Stator coil 54 is wound around stator core 61.

[0006] The operation of the conventional hydrodynamic bearing mechanism constructed as described above and a motor equipped with the same will be described. When the stator coil 54 is energized sequentially according to the rotation phase of the rotor, a torque is generated between the stator coil 54 and the magnet 55 in accordance with Fleming's left-hand rule. As a result, the integrated component including the magnet 55, the yoke 56, the hub 51, the rotating shaft 52, and the thrust flange 58 starts rotating. Further, the rotating shaft 52 and the radial bearing portions 57a, 57b
Filled in the bearing gap between the upper surface of the thrust plate 59 and the lower surface of the thrust flange 58 generate dynamic pressure by the wedge-shaped and spiral grooves, respectively, so that the rotating shaft 52 And the thrust flange 58 is levitated. This allows the rotor to rotate without contact.

[0007]

In the above-described conventional hydrodynamic bearing mechanism and the conventional motor equipped with the hydrodynamic bearing mechanism, the oil is merely held in the narrow bearing gap by the surface tension. Was. For this reason, in a conventional fluid bearing mechanism and a conventional motor equipped with the fluid bearing mechanism, when an external exciting force or impact force due to vibration or impact is applied to the motor, an inertial force acting on oil, particularly oil When the specific gravity is large, the inertia force may overcome the surface tension, and the oil may leak out of the bearing gap. As a result, in the conventional hydrodynamic bearing mechanism and the conventional motor equipped with the hydrodynamic bearing mechanism, the required oil dynamic pressure cannot be obtained due to lack of oil in the bearing gap, and the rotating body is inclined to reduce the rotational accuracy. Led to a decline. Furthermore, in the conventional fluid bearing mechanism and the conventional motor equipped with the fluid bearing mechanism, the rotating shaft support is almost in a closed state, and the open end thereof is a bearing gap (radial bearing) provided on the rotor side. Part 57a) only. For this reason, in a conventional fluid bearing mechanism and a conventional motor equipped with the fluid bearing mechanism, oil may escape to the outside from the bearing gap provided on the rotor side due to a change in the surrounding environment. Specifically,
When a conventional motor equipped with a conventional fluid bearing mechanism is assembled in a normal environment (atmospheric pressure) and then transported in a cargo compartment, which is in a low-pressure environment when transported by air, for example, when a rotary shaft support is used during assembly. In some cases, the air sealed in the portion expands due to a change in the surrounding environment, and the oil in the bearing clearance is pushed out through the open end of the rotating shaft support.

Further, in the conventional hydrodynamic bearing mechanism and the conventional motor equipped with the hydrodynamic bearing mechanism, the oil leaked as described above is atomized by the rotation of the rotating shaft and the rotor, and is external to the motor. Sometimes scattered.
As a result, the scattered oil adheres to, for example, a disk-shaped recording medium, and there is a problem that data recorded on the recording medium cannot be read. Further, oil may adhere between the head and the recording medium and damage the hard disk device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. For example, when oil leaks from a rotating shaft support portion due to an external oscillating force or impact force due to vibration or impact. However, an object of the present invention is to provide a fluid bearing mechanism capable of returning oil to a rotary shaft support without scattering to the outside of the motor, and a motor equipped with the fluid bearing mechanism. In addition, the present invention prevents the oil from being pushed out of the rotary shaft support and leaking out due to expansion of the sealed air even when the surrounding environment changes, thereby preventing the oil from scattering outside the motor. It is an object of the present invention to provide a fluid bearing mechanism that can perform the above-described operation, and a motor equipped with the fluid bearing mechanism.

[0010]

SUMMARY OF THE INVENTION A hydrodynamic bearing mechanism according to the present invention fills a predetermined gap formed between a rotating shaft rotating in one direction and the rotating shaft with oil, and uses a dynamic pressure of the oil to fill the gap. A rotary shaft supporting part having a radial bearing means and a thrust bearing means for rotatably supporting the rotary shaft, and having a closed end and an open end at one end and the other end, respectively, and integrally rotating with the rotary shaft; And an oil sealing portion that rotates integrally with the rotor and that is opposed to an open end of the rotating shaft support portion via a predetermined gap, and has a spiral groove portion on the opposed arrangement surface. The helical groove is formed so that the oil leaking into the gap moves toward the rotary shaft support as the rotor rotates. With this configuration, even if oil leaks out of the rotary shaft support due to external excitation or impact force due to vibration or impact, the oil does not scatter to the outside of the motor and the rotary shaft support does not scatter. Can be returned to the oil.

According to another aspect of the present invention, there is provided a hydrodynamic bearing mechanism in which a rotary shaft rotating in one direction and a predetermined gap formed between the rotary shaft and the rotary shaft are filled with oil, and the rotary shaft is driven by an oil dynamic pressure. A rotating shaft support portion comprising a radial bearing means and a thrust bearing means for rotatably supporting the bearing, and a space between the radial thrust formed between the radial bearing means and the thrust bearing means, and the outside of the rotating shaft support portion. A communication portion that communicates with at least one of the radial gap portions formed between the portion and the radial bearing means, and applying an oil repellent to at least the inner surface of the gap portion side of the communication portion, The air in the gap is released to the outside. With this configuration, even when the surrounding environment changes, oil can be prevented from leaking out of the rotary shaft support, and the oil can be prevented from being scattered outside the motor.

A fluid bearing mechanism according to another aspect of the present invention has a rotating shaft that rotates in one direction, at least one sleeve, and a sleeve holding member that fits and holds the sleeve, and is provided between the rotating shaft and the rotating shaft. A predetermined gap formed is filled with oil, and a rotary shaft support portion including a radial bearing means and a thrust bearing means for rotatably supporting the rotary shaft by the dynamic pressure of the oil, and an outer portion of the rotary shaft support portion. When,
A communication portion that communicates with at least one of the radial thrust gap formed between the radial bearing means and the thrust bearing means and the radial gap formed between the radial bearing means; The communication portion is provided on the sleeve or the sleeve holding member, and is formed in a wedge shape so that a cross-sectional shape thereof becomes wider toward the outside. With this configuration, even when the surrounding environment changes, oil can be prevented from leaking out of the rotary shaft support, and the oil can be prevented from being scattered outside the motor.

According to another aspect of the present invention, there is provided a hydrodynamic bearing mechanism having a rotating shaft that rotates in one direction, at least one sleeve, and a sleeve holding member that fits and holds the sleeve. Filling the formed predetermined gap with oil, a rotary shaft support portion including radial bearing means and thrust bearing means for rotatably supporting the rotary shaft by the oil dynamic pressure, the sleeve and the sleeve holding member, An annular groove provided between the radial bearing, the annular groove, a radial thrust gap formed between the radial bearing means and the thrust bearing means, and a radial gap formed between the radial bearing means. A first communication portion communicating with at least one of the gap portions, and the annular groove portion is connected to a position different from the first communication portion, and the annular groove portion and the outside And a second communicating portion for passing. With this configuration, even if oil leaks from the rotary shaft support, the oil can be returned to the rotary shaft support without being scattered outside the motor.

According to another aspect of the present invention, there is provided a hydrodynamic bearing mechanism wherein a rotary shaft rotating in one direction, a predetermined gap formed between the rotary shaft and the rotary shaft is filled with oil, and the rotary shaft is driven by an oil dynamic pressure. A rotating shaft support part comprising a radial bearing means and a thrust bearing means for rotatably supporting the rotor, a rotor integrally rotating with the rotating shaft, and a rotor provided between the rotor and the rotating shaft bearing part; An oil absorbing member that absorbs oil leaked from an open end of the rotating shaft support, wherein the oil absorbing member rotates the rotor in a gap between the rotor and the rotating shaft support; It is configured to adsorb and absorb the oil in the airflow generated by this. With this configuration, even if oil leaks out of the rotary shaft support, it can be suppressed from scattering outside the motor.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a fluid bearing mechanism of the present invention and a motor equipped with the fluid bearing mechanism will be described below with reference to the drawings. In the following description, a motor built in a hard disk drive will be described as an example for easy comparison with the conventional example.

First Embodiment FIG. 1 is a cross-sectional view showing the structure of a fluid bearing mechanism according to a first embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In FIG. 1, a fluid bearing mechanism according to the present embodiment fills a rotary shaft 2 rotating in one direction and a predetermined gap formed between the rotary shaft 2 with oil (not shown). A rotary shaft supporting portion for rotatably supporting the rotary shaft 2 by an oil dynamic pressure is provided. Further, the hydrodynamic bearing mechanism of the present embodiment has a rotor that rotates integrally with the rotary shaft 2 and a predetermined gap at the open end of the rotary shaft support that rotates integrally with the rotor. And an oil sealing portion having a spiral groove on the facing surface. The rotor includes a hub 1, a magnet 5, a yoke 6, and a thrust flange 8. The hub 1 has a disk-shaped recording medium (not shown) mounted thereon, is press-fitted into one end of the rotating shaft 2, and rotates together in one direction. A yoke 6 made of a soft magnetic material and a magnet 5 are bonded on the inner peripheral surface of the hub 1. A plurality of N poles and S poles are alternately magnetized on the inner peripheral cylindrical surface of the magnet 5. Further, a thrust flange 8 is fixed to the other end of the rotating shaft 2 with a screw 10 and is formed integrally with the rotating shaft 2.

The rotary shaft support is provided with a rotary shaft 2 in the radial direction.
Radial bearing means for supporting the rotating shaft 2 in the thrust direction
And thrust bearing means for supporting the bearing.
More specifically, the base 3 of the rotating shaft support portion includes the rotating shaft 2
Radial bearing portions 7a having a diameter several μm larger than the diameter of
7b is formed along the rotation axis direction. Therefore, between the rotary shaft 2 and each of the radial bearings 7a and 7b, a bearing gap having the above-mentioned predetermined gap of several μm is formed. Further, a radial gap 11 is provided between the rotating shaft 2 and the radial bearings 7a and 7b. The radial gap 11 has an inner cylindrical surface of the base 3 10 to 500 μm larger than the radial bearings 7a and 7b.
It is formed by shaving with a degree.

A plurality of wedge-shaped grooves (not shown) for generating dynamic pressure are provided on the inner peripheral cylindrical surfaces of the radial bearing portions 7a and 7b, for example, by a rolling method. Oil that generates dynamic pressure is injected into these wedge-shaped grooves. As a result, the bearing gap is filled with oil, and radial bearing means is formed. In this radial bearing means, the grooves for generating the dynamic pressure are provided in the radial bearing portions 7a, 7a.
Instead of providing the groove on the inner peripheral cylindrical surface of b, the above-described groove may be formed on the outer peripheral surface of the rotating shaft 2 by using a rolling method, a photolithographic etching method, or a blasting method.
The specific shape of the groove for generating dynamic pressure includes a squeeze type, a herringbone type, and a spiral type.

A thrust plate 9 is opposed to the thrust flange 8. This thrust plate 9
Is press-fitted into the open end of the base 3 and the open end is airtightly fixed with an adhesive. A plurality of spiral grooves (not shown) for generating dynamic pressure are formed on the lower surface of the thrust flange 8 or the upper surface of the thrust plate 9 by an etching method or a coining method. Oil that generates dynamic pressure is injected into these spiral grooves. As a result, the bearing gap formed between the lower surface of the thrust flange 8 and the upper surface of the thrust plate 9 is filled with oil, thereby forming a thrust bearing means. The radial thrust interspace 12 is provided between the thrust bearing means and the radial bearing part 7b of the radial bearing means. More specifically, the radial thrust gap 12 is 10 to 5 mm.
The radial bearing portion 7 is formed by a gap of about 00 μm.
It is provided between the rotating shaft 2, the base 3, and the thrust flange 8 below b. In the motor equipped with the hydrodynamic bearing mechanism of the present embodiment, a stator core 30 and a plurality of phases of stator coils 4 are provided on the outer peripheral cylindrical surface of the base 3 in order to rotate the rotating shaft 2 and the rotor. I have. The stator core 30 is formed by stacking a plurality of disk-shaped magnetic materials in the rotation axis direction, and is adhered and fixed on the outer peripheral cylindrical surface of the base 3. Stator coil 4 is wound around stator core 30.

In the hydrodynamic bearing mechanism of this embodiment, a radial scraping member 13 is provided as the above-mentioned oil sealing portion. The radial scraping member 13 will be specifically described with reference to FIGS. 2, 3A and 3B. FIG. 2 is an enlarged cross-sectional view showing a detailed configuration of a fluid bearing mechanism near the radial scraping member shown in FIG. FIGS. 3A and 3B are explanatory views showing the configuration and function of the radial scraping member shown in FIG. As shown in FIG. 2, the disk-shaped radial scraping member 13 has an outer peripheral surface and an inner peripheral surface that are in contact with the inner peripheral wall surface 1 a of the hub 1 of the rotor and the outer peripheral surface of the rotating shaft 2, respectively.
The hub 1 is adhesively fixed to one inner end face. Further, as shown in the figure, the radial scraping member 13 is arranged to face the open end of the base 3 via the open end gap 40, which is the predetermined gap. As shown in the figure, the above-described oil 101 is filled in the gap between the rotating shaft 2 and the base 3 (the radial bearing portion 7a).

As shown in FIG. 3, a spiral groove having a plurality of, for example, four spiral grooves is formed on the facing surface of the radial scraping member 13 facing the open end. The helical groove moves oil leaking into the open end gap 40 (FIG. 1), which is a gap with the base 3, with the rotation of the hub 1 (FIG. 1) to the radial bearing 7a side of the rotary shaft support. It is formed so that. More specifically, in FIG. 3, the spiral groove portions 13a are indicated by hatched portions, and the groove portions 13a are alternately arranged with the groove portions 13a to form the above-described four spiral grooves 13b. It is composed of Since the radial scraping member 13 is fixed to the hub 1 as described above, the radial scraping member 13 rotates integrally with the rotating shaft 2 and the rotor in the clockwise direction shown in the drawing in the rotation direction of FIG. On the other hand, the spiral groove (groove valley 13b) is formed in a counterclockwise direction opposite to the above-described rotation direction, as shown in FIG. As a result, the leaked oil droplet 100 leaked into the open end gap 40 shown in FIG. 2 is rotated by the rotation of the hub 1 and the rotary shaft 2 and the radial bearing 7 as described later in detail.
Move to a. The distance between the groove crest 13a and the open end face of the base 3 (the minimum dimension of the open end gap 40) is 50
It is set in the range of μm to 0.3 mm.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described. First, the basic operation of the motor will be described with reference to FIG. When the stator coil 4 is energized sequentially according to the rotation phase of the rotor, a torque is generated between the stator coil 4 and the magnet 5 according to Fleming's left-hand rule. Thereby, the magnet 5, the yoke 6, the hub 1, the rotating shaft 2, the thrust flange 8, and the radial scraping member 13 start rotating integrally. The oil injected between the rotary shaft 2 and the radial bearing portions 7a and 7b, and between the upper surface of the thrust plate 9 and the thrust flange 8 generates dynamic pressure by the wedge-shaped groove and the spiral groove, respectively. 2 and the thrust flange 8 are levitated. This allows the rotor to rotate without contact.

Next, the function of the radial scraping member 13 will be described with reference to FIGS. 1, 3A and 3B. In the hydrodynamic bearing mechanism of the present embodiment, the thrust plate 9 constituting the thrust bearing means is fixed to the base 3 by press-fitting, so that oil does not leak from the thrust bearing means side. Meanwhile, base 3
The oil is not sealed on the open end side of the motor, so if a force is applied from outside the motor due to strong vibration during transportation or installation of the hard disk drive, the oil will be applied to the radial bearing near the open end. 7a may leak.
The leaked oil droplet 100 comes into contact with and adheres to the surface of the radial scraping member 13. More specifically, as shown in FIG. 3A, when the motor (hub 1) starts rotating clockwise, the leaked oil droplet 100 attached to the surface of the groove 13b becomes a spiral groove (groove 13b). Along the inner peripheral side of the radial scraping member 13, that is, toward the rotating shaft 2 and the radial bearing portion 7 a, which are the directions to be sealed again. Further, as shown in FIG.
The leaked oil droplet 100 adhering to a is once scattered to the outer peripheral side due to centrifugal force, but is prevented from being scattered on the wall surface of the groove 13b or the inner peripheral wall 1a of the hub 1, falls into the groove 13b and is sealed again. It is returned to the direction to be stopped. Also, the leaked oil droplets that have adhered to the open end surface of the base 3 without adhering to the radial scraping member 13 adhere to the surface of the groove crest 13a or groove trough 13b due to the air current generated by the rotation of the radial scraping member 13. Then, it is returned to the direction to be sealed again.

As described above, the hydrodynamic bearing mechanism of the present embodiment
And a motor equipped with the fluid bearing mechanism, the radial retraction member 13 rotates the base 3 with the rotation of the hub 1.
And a spiral groove formed so that the oil leaking into the gap (open end gap 40) between the oil and the air moves toward the radial bearing 7a. Further, the radial scraping member 13
Is fixed to the hub 1 so as to face the open end of the base 3 so that the spiral groove is disposed on a plane perpendicular to the rotating shaft 2. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even if oil leaks out of the bearing gap due to external oscillating force or impact force due to vibration or shock, radial The scraping-back member 13 can move in the sealing direction again and return to the original bearing gap without scattering the oil leaked by the rotation of the hub 1 to the outside of the motor.
As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, it is possible to prevent the oil from running short in the bearing gap. Further, the oil can be prevented from being scattered to the outside of the motor, so that contamination due to the scattered oil can be prevented. For example, even when the oil is built in a hard disk device, data cannot be read due to the adhesion of the scattered oil.

In the above description, the radial scraping member 13 is a member separate from the hub 1. However, the present invention is not limited to this, and the groove trough 13b which is a spiral groove is formed on the hub 1. The radial scraping member 13 and the hub 1 may be formed integrally by a milling method or a coining method. Further, the number of spiral grooves is not limited to four.

<< Second Embodiment >> FIG. 4 is a cross-sectional view showing the configuration of a fluid bearing mechanism according to a second embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, the spiral groove of the oil sealing portion is arranged on a cylindrical surface coaxial with the rotation axis. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. As shown in FIG. 4, in the hydrodynamic bearing mechanism of the present embodiment, a thrust scraping member 17, which is an oil sealing portion, is adhesively fixed to the inner peripheral portion of the hub 1 so as to surround the open end of the base 3. ing. More specifically, as shown in FIG. 5 which is a perspective view of the thrust scraping member 17, the thrust scraping member 17 is formed in a cylindrical shape, and has a plurality of, for example, four spiral grooves on its inner peripheral cylindrical surface. A groove is provided. The spiral groove is composed of groove peaks 17a and groove troughs 17b alternately arranged. The thrust scraping member 17 rotates integrally with the rotor in a counterclockwise direction (shown in the “rotation direction” in the figure), but the groove groove 17 b which is a spiral groove moves in a direction to reseal the leaked oil droplet 100. Is formed. That is, when the rotor rotates counterclockwise, the groove valley portion 17b is formed in a direction forming a left-hand thread. When the rotor rotates in the opposite clockwise direction, the groove valley portion 17b is also formed in a direction forming an opposite right-hand thread. The distance between the groove 17a and the outer peripheral portion near the open end of the base 3 is set in the range of 20 to 300 μm.

The operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described below with reference to FIG. In the following description, only the function of the thrust scraping member 17 will be described for simplification of the description. As shown in FIG.
The leaked oil droplet 100 comes into contact with and adheres to the surface of the thrust scraping member 17. For details, see Mizotani 17
When the motor (hub 1) starts rotating counterclockwise, the leaked oil droplet 100 attached to the surface of b is lifted up along the spiral groove (groove groove 17b) and returned to the direction in which it is sealed again. . Further, the leaked oil droplets 100 attached to the groove 17a or the outer peripheral portion of the base 3 are gradually delayed with respect to the rotation by the airflow generated between the groove 3 and the base 3 due to the rotation of the thrust scraping member 17. . That is, as shown by the arrow in FIG. 5, the leaked oil droplet 100 moves and falls into the groove valley portion 17 b, and is then lifted up with the rotation of the thrust scraping member 17 and sealed again. It is returned to the direction of the part 7a.

As described above, the hydrodynamic bearing mechanism of this embodiment
And a motor equipped with the hydrodynamic bearing mechanism, the thrust scraping member 17 rotates the base 3 with the rotation of the hub 1.
And a helical groove formed so that oil leaked into the gap between the spiral groove and the radial bearing 7a moves to the radial bearing 7a side. Further, the thrust scraping member 17 is fixed to the hub 1 so as to surround the open end of the rotary shaft support so that the spiral groove is disposed on a cylindrical surface coaxial with the rotary shaft 2.
Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even if oil leaks out of the bearing gap due to external oscillating force or impact force due to vibration or impact, the thrust The scraping member 17 can move in the sealing direction again and return to the original bearing gap without scattering the oil leaked by the rotation of the hub 1 to the outside of the motor. As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, it is possible to prevent the oil from running short in the bearing gap. Furthermore, since the oil can be prevented from being scattered outside the motor, contamination due to the scattered oil can be prevented.
Data cannot be read out due to the attachment of the scattered oil. In the above description, the case where four groove valleys 17b are provided has been described, but the number of groove valleys 17b is not limited to this.

Third Embodiment FIG. 6 is a sectional view showing the structure of a fluid bearing mechanism according to a third embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, the spiral groove of the oil sealing portion is arranged on a plane perpendicular to the rotation axis and on a coaxial cylindrical surface. The other parts are the same as those of the second embodiment, and the duplicated description thereof will be omitted. FIG.
As shown in the figure, in the fluid bearing mechanism of the present embodiment, the radial thrust scraping member 17 ′ as the oil sealing means is
The base 3 is adhesively fixed to the inner peripheral portion of the hub 1 so as to face the open end surface and surround the open end. That is, the radial thrust scraping member 17 ′
Is a structure in which the radial scraping member 13 (FIG. 1) and the thrust scraping member 17 (FIG. 4) shown in the first and second embodiments are integrally formed. 13b and 17b are connected to each other (not shown).

The operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described below with reference to FIG. In the following description, for the sake of simplicity, only the function of the radial thrust scraping member 17 'will be described. In FIG. 6, when a leaked oil drop (not shown) adheres to a groove (not shown) on the cylindrical surface of the radial thrust scraping member 17 ', the leaked oil drop is the same as in the second embodiment. Then, it is scooped up along the groove with the rotation of the motor (hub 1). Thereafter, the leaked oil droplets are moved along the inner peripheral side of the radial thrust scraping member 17 'along a groove (not shown) on the flat plate, as in the first embodiment.
That is, it is returned in the direction of the radial bearing portion 7a to be sealed again.

As described above, the hydrodynamic bearing mechanism of this embodiment
Also, in the motor equipped with the fluid bearing mechanism, the radial thrust scraping member 17 ′ causes the oil leaked into the gap between the hub 3 and the base 3 to move toward the radial bearing portion 7 a with the rotation of the hub 1. It has a formed spiral groove. Further, a radial thrust scraping member 17 ′
The base 3 is arranged such that the spiral groove is disposed on a plane perpendicular to the rotation axis 2 and on a coaxial cylindrical surface.
And is fixed to the hub 1 so as to surround the open end face of the base and the open end. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even if oil leaks out of the bearing gap due to external oscillating force or impact force due to vibration or shock, radial The thrust scraping member 17 'does not scatter the oil leaked by the rotation of the hub 1 to the outside of the motor.
It can be moved in the sealing direction again to return to the original bearing clearance. As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, it is possible to prevent the oil from running short in the bearing gap. Further, the oil can be prevented from being scattered to the outside of the motor, so that contamination due to the scattered oil can be prevented. For example, even when the oil is built in a hard disk device, data cannot be read due to the adhesion of the scattered oil.

<< Fourth Embodiment >> FIG. 7 is a sectional view showing the structure of a fluid bearing mechanism according to a fourth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, the helical groove of the oil sealing portion is arranged on a conical surface coaxial with the rotation axis. The other parts are the same as those of the third embodiment, and the duplicated description thereof will be omitted. As shown in FIG. 7, in the hydrodynamic bearing mechanism of the present embodiment, the tapered scraping member 23, which is an oil sealing means, faces the open end of the base 3 on the conical surface of the inner peripheral portion of the hub 1. Is provided. The tapered scraping member 23 has a helical groove having a helical groove formed in a direction opposite to the rotation direction of the rotating shaft 2 on the inner peripheral conical surface of the hub 1 having a predetermined inclination angle with respect to the rotating shaft 2. Is formed by notch (or cutting) or plastic working by a milling method or a coining method. Further, for example, four spiral grooves are formed in the same manner as in the first to third embodiments. Further, the open end of the base 3
It is formed in a tapered shape so as to be arranged at a predetermined distance (for example, in a range of 50 to 500 μm) from the groove crest of the tapered scraping member 23.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described with reference to FIG. In the following description, only the function of the tapered scraping member 23 will be described for simplification of the description. In FIG. 7, when a leaked oil droplet (not shown) adheres to a groove (not shown) on the cylindrical surface of the tapered scraping portion 23, the leaked oil droplet is removed in the same manner as in the second embodiment. The radial bearing portion 7a which is scraped up along the groove and valley along with the rotation of the motor (hub 1) and is re-sealed on the outer peripheral surface side of the rotating shaft 2
In the direction of

As described above, the hydrodynamic bearing mechanism of this embodiment
And a motor equipped with the hydrodynamic bearing mechanism, the tapered scraping member 23 rotates the base 3 with the rotation of the hub 1.
And a helical groove formed so that oil leaked into the gap between the spiral groove and the radial bearing 7a moves to the radial bearing 7a side. Further, the tapered scraping member 23 is provided on the hub 1 so as to face the open end of the base 3 so that the spiral groove is disposed on a conical surface coaxial with the rotating shaft 2. Thereby, in the fluid bearing mechanism of the present embodiment, and in the motor equipped with the fluid bearing mechanism, even if oil leaks out of the bearing gap portion due to external exciting force or impact force due to vibration or impact, the taper The scraping member 23 can move in the sealing direction again and return to the original bearing clearance without scattering the oil leaked by the rotation of the hub 1 to the outside of the motor. As a result, in the fluid bearing mechanism of the present embodiment, and the motor equipped with the fluid bearing mechanism,
Oil can be prevented from running short in the bearing gap. Further, the oil can be prevented from being scattered to the outside of the motor, so that contamination due to the scattered oil can be prevented. For example, even when the oil is built in a hard disk device, data cannot be read due to the adhesion of the scattered oil.

<< Fifth Embodiment >> FIG. 8 is a sectional view showing the structure of a fluid bearing mechanism according to a fifth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. FIG. 9 shows FIG.
FIG. 3 is an enlarged cross-sectional view showing a configuration of a portion surrounded by a dashed line T. In this embodiment, in the configuration of the fluid bearing mechanism, a rotary shaft taper portion formed in a tapered shape such that the diameter of the rotary shaft increases toward the rotary shaft support portion is provided on the rotary shaft. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. As shown in FIGS. 8 and 9, in the fluid bearing mechanism of the present embodiment, the rotating shaft taper portion 24 is provided on the outer peripheral portion of the rotating shaft 2 facing the radial scraping portion 13. The rotating shaft taper portion 24 is formed in a tapered shape such that the diameter increases as approaching the radial bearing portion 7a (the rotating shaft support portion).

The operation of the hydrodynamic bearing mechanism and the motor according to this embodiment will be described below with reference to FIG. In the following description, only the function of the rotating shaft taper portion 24 will be described for simplification of the description. As shown in FIG. 9, when the leaked oil droplet 100 adheres to a groove (not shown) of the radial scraping portion 13, the leaked oil droplet (shown by a broken line in the drawing) is of the first embodiment. In the same manner as described above, with the rotation of the motor, it is returned to the inner peripheral side of the radial scraping-back section 13 along the groove and valley, that is, the direction in which sealing is performed again. Thereafter, the leaked oil droplet 100 (shown by a solid line in the figure) adheres to the rotating shaft taper portion 24. Then, the leaked oil droplet 100 tends to move to the outer peripheral side due to centrifugal force with the rotation of the rotating shaft 2, but moves to the rotating shaft support portion because it is attached on the rotating shaft taper portion 24. . Thus, the leaked oil droplet 100 is integrated with the oil 101 sealed in the radial bearing portion 7a.

As described above, the hydrodynamic bearing mechanism of the present embodiment
And a motor equipped with the hydrodynamic bearing mechanism, the rotating shaft 2
Has a rotating shaft tapered portion 24 formed in a tapered shape such that its diameter increases toward the rotating shaft support portion.
Thereby, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even if oil leaks out of the bearing gap due to external excitation force or impact force due to vibration or impact, rotation The shaft tapered portion 24 can move in the sealing direction again without returning the leaked oil to the outside of the motor and return to the original bearing clearance. As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, it is possible to prevent the oil from running short in the bearing gap. Further, the oil can be prevented from being scattered to the outside of the motor, so that contamination due to the scattered oil can be prevented. For example, even when the oil is built in a hard disk device, data cannot be read due to the adhesion of the scattered oil.

<< Sixth Embodiment >> FIG. 10 shows a sixth embodiment of the present invention.
FIG. 1 is a cross-sectional view illustrating a configuration of a fluid bearing mechanism according to an embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, a communication portion that connects the outside and the inside (gap) is provided on the rotating shaft support portion, and an oil repellent is applied to at least the inner surface of the communication portion on the gap side. . In the following description, for the sake of simplicity, the first description will be omitted.
The same members as those of the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated. As shown in FIG. 10, in the hydrodynamic bearing mechanism of the present embodiment, the ventilation hole 15 is provided in the base 3. The ventilation hole 15 constitutes a communicating portion that communicates the outside of the base 3 with the gap portion 12 between radial thrusts, and is sealed to the rotating shaft support portion due to a change in the surrounding environment, as described later in detail. Even if the air expands, it is possible to prevent oil from leaking. In addition, ventilation holes 15
Is provided on the base 3 so that the rotating shaft 2
Can easily be inserted and assembled. The sealed air includes not only the air trapped in the radial gaps 11 and the radial thrust gaps 12, but also fine air bubbles mixed in the oil.

As shown in the figure, the ventilation hole 15 is preferably inclined upward from the radial thrust interspace 12 to communicate with the outside. The specific diameter of the ventilation hole 15 is, for example, 0.5 mm. In the ventilation hole 15, an oil repellent 25 is applied to at least the inner surface in the vicinity of the radial thrust gap 12. The oil repellent 25 degrades the wettability of the oil, thereby allowing the oil to pass through the ventilation holes 1.
5 to prevent leakage to the outside.
Specifically, the oil repellent 25 is preferably one in which a fluorinated organic chemical is dissolved in a volatile solvent, and is applied to a predetermined portion with a dispenser such as a syringe and then dried.

The operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described below with reference to FIG. In the following description, only the function of the ventilation hole 15 will be described for simplification of the description. In FIG. 10, the air sealed in the rotating shaft support when the motor is assembled expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, as the surrounding air pressure decreases. As described above, when the air is expanded due to a change in the surrounding environment and the ventilation hole 15 is not provided, the oil is pushed out of the rotary shaft supporting portion by the amount of the air expansion as in the conventional example shown in FIG. It is.
On the other hand, in the fluid bearing mechanism and the motor of the present embodiment, since the ventilation hole 15 communicates the radial thrust interspace 12 with the outside of the base 3, even if the sealed air expands, it is not affected. The pressure of the expanded air can be released by the ventilation hole 15. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, since the oil repellent 25 is applied to the inner surface of the ventilation hole 15, even if oil expands and leaks to the outside through the ventilation hole 15, the wettability on the inner surface of the ventilation hole 15 is poor. The oil is immediately returned to the radial thrust gap 12, and further returned to the bearing gap on the thrust plate 9.

As described above, the hydrodynamic bearing mechanism of this embodiment
And a motor equipped with the hydrodynamic bearing mechanism, the base 3
Is provided with a ventilation hole 15 that communicates with the outside and the radial thrust gap 12. Further, an oil repellent 25 is applied to the inner surface of the ventilation hole 15 at least in the vicinity of the radial thrust gap 12. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

In the above description, a configuration was described in which only the ventilation hole 15 for communicating the gap 12 between the radial thrusts and the outside of the base 3 was provided. For example, as shown in FIG. Another ventilation hole 15 that communicates 11 with the outside of the base 3 may be provided. Further, as shown in the figure, the thrust bearing means may be constituted by the end face of the rotating shaft 2 and the thrust plate 9 without using the thrust flange.

<< Seventh Embodiment >> FIG. 12 shows a seventh embodiment of the present invention.
FIG. 1 is a cross-sectional view illustrating a configuration of a fluid bearing mechanism according to an embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, a base is formed by a sleeve and a sleeve holding member that fits and holds the sleeve, and a communication portion formed in a wedge shape so as to become wider toward the outside is provided on the sleeve. . In the following description,
For the sake of simplicity of description, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description thereof will be omitted. As shown in FIG. 12, in the hydrodynamic bearing mechanism of the present embodiment, the base 3 has a cylindrical sleeve 14 and the sleeve 14.
Is provided with a sleeve holding member 34 for fitting and holding. The sleeve 14 is provided with radial bearing portions 7a and 7b on an inner peripheral portion thereof.

A plurality of, for example, three wedge-shaped gap portions 19a are formed in the outer peripheral portion of the sleeve 14 by a rolling method. These wedge-shaped gap portions 19 a are arranged at equal intervals on the concentric circumference of the rotating shaft 2. Each wedge-shaped gap 1
9a constitutes a communicating portion which communicates the outside of the sleeve 14 with the radial thrust gap 12 between the thrust flange 8 and the sleeve 14. Further, each wedge-shaped gap portion 19 a is formed so as to become wider toward the outside of the sleeve 14. Thereby, the wedge-shaped gap portion 19a can return the oil that has entered the wedge-shaped gap portion 19a to the inter-radial thrust gap portion 12 without applying the oil repellent 25 shown in the sixth embodiment. . In detail, even when the oil enters the wedge-shaped gap portion 19a,
The oil is returned by the surface tension in a direction closer to a portion having a narrower gap, that is, a space 12 between radial thrusts. Further, the wedge-shaped gap portion 19a is
, The sleeve 14 can be easily fitted and assembled to the sleeve holding member 34.

The operation of the hydrodynamic bearing mechanism and the motor according to this embodiment will be described below with reference to FIG. In the following description, only the function of the wedge-shaped gap 19a will be described for simplification of the description. In FIG. 12, the air sealed in the rotary shaft support when the motor is assembled expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, as the surrounding air pressure decreases. In this way, when the air expands due to a change in the surrounding environment, the wedge-shaped gap portion 19a
Is not provided, as in the conventional example shown in FIG.
The oil is pushed out of the rotary shaft support by the amount of expansion of the air. On the other hand, in the fluid bearing mechanism and the motor of the present embodiment, since the wedge-shaped gap portion 19a communicates between the radial thrust gap portion 12 and the outside of the sleeve 14, even if the sealed air expands. The pressure of the expanded air can be released by the wedge-shaped gap 19a.
As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, since the wedge-shaped gap portion 19a is formed so as to become wider toward the outside of the sleeve 14, the oil that has entered the wedge-shaped gap portion 19a has a narrower gap due to its own surface tension.
That is, it is returned to the radial thrust gap 12 and further returned to the bearing gap on the thrust plate 9.

As described above, the hydrodynamic bearing mechanism of this embodiment
Further, in the motor equipped with the fluid bearing mechanism, a wedge-shaped gap portion 19a is provided for communicating the outside of the sleeve 14 and the gap portion 12 between radial thrusts. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

<< Eighth Embodiment >> FIG. 13 shows an eighth embodiment of the present invention.
FIG. 1 is a cross-sectional view illustrating a configuration of a fluid bearing mechanism according to an embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, an annular groove is provided between the sleeve and the sleeve holding member. The other parts are the same as those of the seventh embodiment, and the duplicated description thereof will be omitted. As shown in FIG. 13, in the hydrodynamic bearing mechanism of this embodiment, the base 3 is a cylindrical sleeve 1.
4 'and a sleeve holding member 35 for fitting and holding the sleeve 14'. An annular groove 20 is provided between the sleeve 14 'and the sleeve holding member 35 for connecting the radial gap 11 and the wedge-shaped gap 19a provided in the sleeve 14'. That is,
One end surface of the sleeve 14 ′ is fitted and held at a predetermined distance with respect to the sleeve holding member 35, and forms an annular groove 20 with the sleeve holding member 35.

The sleeve 14 'is provided with a radial bearing 7a on its inner peripheral portion. Also, sleeve 1
On the outer peripheral portion of 4 ′, 3
Two wedge-shaped gap portions 19a are formed by a rolling method. Each wedge-shaped gap portion 19a constitutes a communication portion that communicates the outside of the sleeve 14 ′ and the radial gap 11 via the annular groove portion 20. Furthermore, each wedge-shaped gap 1
9a is formed so as to become wider toward the outside of the sleeve 14 '. As a result, the wedge-shaped gap 19
Even if the oil enters the space a, the oil tends to return again to a portion having a narrower gap, that is, the annular groove 20 due to surface tension. The sleeve holding member 35 is provided with a radial bearing portion 7b included in the radial bearing means on the circumferential inner cylindrical surface.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described with reference to FIG. In the following description, for the sake of simplicity, only the functions of the wedge-shaped gap 19a and the annular groove 20 will be described. FIG.
In the above, when the motor is assembled, the air sealed in the rotary shaft support expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, as the surrounding air pressure decreases. As described above, when the air expands due to a change in the surrounding environment and the wedge-shaped gap portion 19a and the annular groove portion 20 are not provided, the oil is rotated by an amount corresponding to the expansion of the air, as in the conventional example shown in FIG. It is pushed out from the bearing. On the other hand, in the hydrodynamic bearing mechanism and the motor according to the present embodiment, the wedge-shaped gap portion 19a communicates the outside of the sleeve 14 ′ with the inter-radial gap portion 11 via the annular groove portion 20, so that it is sealed. Even if the air expands, the pressure of the expanded air can be released by the wedge-shaped gap portion 19a and the annular groove portion 20. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, since the wedge-shaped gap portion 19a is formed so as to become wider toward the outside of the sleeve 14 ', the oil that has entered the wedge-shaped gap portion 19a causes a portion having a narrower gap due to its own surface tension, that is, an annular groove portion. 20 (the radial gap 11).

As described above, in the hydrodynamic bearing mechanism of this embodiment and the motor having the hydrodynamic bearing mechanism, the sleeve 1
An annular groove 20 is provided between the sleeve 14 'and the sleeve holding member 35 for connecting the wedge-shaped gap 19a connected to the outside of the 4' to the radial gap 11.
Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

<< Ninth Embodiment >> FIG. 14 shows a ninth embodiment of the present invention.
FIG. 1 is a cross-sectional view illustrating a configuration of a fluid bearing mechanism according to an embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, a plurality of sleeves divided in the axial direction are used, and the annular groove is disposed between the sleeve holding member and each of the plurality of sleeves. The other parts are the same as those of the seventh embodiment, and the duplicated description thereof will be omitted. As shown in FIG. 14, in the hydrodynamic bearing mechanism of this embodiment, the base 3 includes cylindrical sleeves 14a and 14b, and a sleeve holding member 36 for holding the sleeves 14a and 14b. A radial bearing portion 7a is provided on an inner peripheral portion of the sleeve 14a,
A radial bearing 7b is provided on an inner peripheral portion of the sleeve 14b. A plurality of, for example, three wedge-shaped gap portions 19a, 19b are formed on the outer peripheral portions of the sleeves 14a, 14b by a rolling method. These wedge-shaped gap portions 19a, 19b are arranged at equal intervals on the concentric circumference of the rotating shaft 2. Each wedge-shaped gap portion 19a is formed so as to become wider toward the outside of the sleeve 14a. Similarly, each wedge-shaped gap 19b is formed so as to become wider toward the outside of the sleeve 14b.

An annular groove 20 is provided between the sleeve 14a and the sleeve 14b to connect the radial gap 11 and the wedge-shaped gap 19a provided in the sleeve 14a.
Is provided. That is, the sleeve 14a has one end face fitted and held at a predetermined distance from the sleeve 14b to form the annular groove 20 with the sleeve 14b. Similarly, between the sleeve 14b and the sleeve holding member 36, there is provided an annular groove 20 for connecting the radial thrust gap 12 and the wedge-shaped gap 19b provided in the sleeve 14b. That is, the sleeve 14b is fitted and held at one end surface thereof at a predetermined distance from the sleeve holding member 36, and forms the annular groove 20 with the sleeve holding member 36.

The operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described below with reference to FIG. In the following description, the wedge-shaped gap portions 19a,
Only the function of the annular groove 19b and the two annular grooves 20 will be described. In FIG. 14, the air sealed in the rotary shaft support when the motor is assembled expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, with a decrease in the surrounding air pressure. As described above, when the air expands due to a change in the surrounding environment, if the wedge-shaped gaps 19a and 19b and the two annular grooves 20 are not provided, the oil expands as in the conventional example shown in FIG. It is pushed out of the rotary shaft support by the minute. On the other hand, in the fluid bearing mechanism and the motor according to the present embodiment, the outside of the sleeve 14a and the radial gap 11 communicate with each other through the annular groove 20 to which the wedge gap 19a is connected, and the wedge gap 19b is formed. Communicates with the outside of the sleeve 14b and the inter-radial thrust gap 12 through the annular groove 20 connected to the sleeve 14b. For this reason, in the fluid bearing mechanism and the motor of the present embodiment, even if the sealed air expands, the pressure of the expanded air can be released by the wedge-shaped gap portions 19 a and 19 b and the two annular grooves 20. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, since the wedge-shaped gap portions 19a, 19b are formed so as to become wider toward the outside of the sleeves 14a, 14b, respectively, the oil that has entered the wedge-shaped gap portions 19a, 19b has a narrower gap due to its own surface tension. That is, it is returned again in the direction approaching the annular groove 20 (the radial gap 11 and the radial thrust gap 12).

As described above, in the hydrodynamic bearing mechanism of the present embodiment and the motor having the hydrodynamic bearing mechanism mounted thereon, the sleeves 14a and 14b having the radial bearing portions 7a and 7b, respectively.
b, wedge-shaped gap portions 19a and 19b connected to the outside are provided, respectively. Further, the two radial grooves 20 connect the radial gap 11 and the radial thrust gap 12 to the wedge-shaped gaps 19a and 19b, respectively. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented. In the above description, the configuration in which the sleeve 14a is fitted and held in the sleeve 14b has been described. However, the embodiment is not limited to this, and the sleeves 14a and 14b are separately fitted and held in the sleeve holding member 36. The configuration may be as follows.

<< Tenth Embodiment >> FIG. 15 is a sectional view showing the structure of a fluid bearing mechanism according to a tenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, a first communication portion that connects the gap portion and the annular groove portion is provided in the sleeve, and is connected to the annular groove portion at a position different from the first communication portion,
A second communication portion communicating with the annular groove and the outside is provided on the sleeve holding member. In the following description, for the sake of simplicity, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description will be omitted. As shown in FIG. 15, in the hydrodynamic bearing mechanism according to the present embodiment, the base 3 includes a cylindrical sleeve 16 and a sleeve holding member 37 that fits and holds the sleeve 16. The sleeve 16 is provided with radial bearings 7a and 7b on an inner peripheral portion thereof. The annular groove 20 is formed between the sleeve 16 and the sleeve holding member 37.

The sleeve 16 is provided with a ventilation hole 15b, which is a first communication portion for connecting the radial thrust interspace 12 with the annular groove portion 20. The ventilation hole 15b is
As shown in the figure, it is preferable to be inclined upward from the radial thrust gap 12 to communicate with the outside. The sleeve holding member 37 is provided with a ventilation hole 15a that is a second communication portion that connects the annular groove portion 20 to the outside of the base 3. The above-mentioned first and second communication portions are formed in the annular groove portion 2.
0 are arranged at different phases from each other. Specifically, the ventilation holes 15b and the ventilation holes 15a are arranged in different phases. That is, the ventilation holes 15b and 15a
They are connected to different positions of the annular groove portion 20 without being directly connected. Thus, for example, even when a large force due to extremely strong vibration is applied to the motor from the outside, the oil does not leak out from the ventilation hole 15a to the outside, but only accumulates in the annular groove 20 through the ventilation hole 15b. Therefore, in the hydrodynamic bearing mechanism of the present embodiment,
Even if extremely strong vibration is applied, it is possible to prevent oil from scattering to the outside of the motor. The ventilation holes 15a, 15b
Are, for example, 0.4 mm and 0.5 m, respectively.
m.

The operation of the hydrodynamic bearing mechanism and the motor according to this embodiment will be described below with reference to FIG. In the following description, the ventilation holes 15a, 15
Only the functions of b and the annular groove 20 will be described. In FIG. 15, the air sealed in the rotating shaft support when the motor is assembled expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, with a decrease in the surrounding air pressure. As described above, when the air expands due to a change in the surrounding environment and the ventilation holes 15a and 15b and the annular groove 20 are not provided, the oil rotates by the amount of the air expansion as in the conventional example shown in FIG. It is pushed out from the shaft bearing.
On the other hand, in the fluid bearing mechanism and the motor according to the present embodiment, the ventilation hole 15b communicates the radial thrust interspace 12 with the annular groove 20, and the ventilation hole 15a connected to a position different from the ventilation hole 15b is formed. The annular groove 20 communicates with the outside of the base 3. Therefore, in the hydrodynamic bearing mechanism and the motor of the present embodiment, even if the sealed air expands, the pressure of the expanded air can be released by the ventilation holes 15a and 15b and the annular groove 20. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, in the hydrodynamic bearing mechanism and the motor according to the present embodiment, for example, when extremely strong vibration is applied from the outside, the oil flows through the ventilation hole 15b to form the annular groove 2.
There is a possibility of leaking to zero. However, ventilation holes 15
Since a and 15b are arranged in different phases on the annular groove 20, the oil does not leak to the outside through the ventilation hole 15a, and the oil is stored in the annular groove 20.

As described above, the hydrodynamic bearing mechanism of this embodiment
And a motor equipped with the fluid bearing mechanism, the ventilation hole 15b, which is the first communication portion, is formed in the radial thrust gap 1
2 communicates with the annular groove 20. Further, the ventilation hole 15a, which is the second communication portion, is connected to a position different from the ventilation hole 15b on the annular groove portion 20, and communicates the annular groove portion 20 with the outside of the motor. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

<< Eleventh Embodiment >> FIG. 16 is a sectional view showing the structure of a fluid bearing mechanism according to an eleventh embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the structure of the fluid bearing mechanism, a wedge-shaped gap portion is provided in the sleeve as a second communication portion instead of the ventilation hole provided in the sleeve holding member. Other parts are the first
0, which are the same as those of the embodiment of FIG. As shown in FIG. 16, in the hydrodynamic bearing mechanism of the present embodiment, the base 3 includes a cylindrical sleeve 16 'and a sleeve holding member 37' for fitting and holding the sleeve 16 '. The rotating shaft 2 is provided with a rotating shaft tapered portion 24 as in the fifth embodiment described above. As a result, the oil leaked from the radial bearing portion 7a toward the rotor can be returned to the original bearing clearance.
The sleeve 16 'has a radial bearing 7 on its inner peripheral portion.
a, 7b are provided. A wedge-shaped gap portion 19a formed so as to become wider toward the outside of the sleeve 16 'is provided on the outer peripheral portion of the sleeve 16'. The wedge-shaped gap portion 19a is provided in the second
Function as a communication part. An annular groove 20 is formed between the sleeve 16 'and the sleeve holding member 37'.

The sleeve 16 ′ is provided with a ventilation hole 15 b, which is a first communication portion that connects the radial thrust interspace 12 and the annular groove 20. Ventilation hole 15b
Is, as shown in FIG.
It is preferable to be inclined upward from above and communicate with the outside. Further, the sleeve 16 ′ has another first communication portion,
A ventilation hole 15c communicating the radial gap 11 and the annular groove 20 is provided. The specific diameter of the ventilation hole 15c is, for example, 0.5 mm. The above-described first and second communication portions are arranged in the annular groove 20 at different phases. More specifically, each ventilation hole 15b, 15
c and the wedge-shaped gap 19a are connected to different positions of the annular groove 20 without being directly connected. Thus, in the fluid bearing mechanism of the present embodiment, as in the case of the tenth embodiment, even if extremely strong vibration is applied, it is possible to prevent oil from being scattered outside the motor.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor of this embodiment will be described with reference to FIG. In the following description, the ventilation holes 15b and 15
Only the functions of the c, the wedge-shaped gap 19a, and the annular groove 20 will be described. In FIG. 16, the air sealed in the rotary shaft support when the motor is assembled expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, as the atmospheric pressure decreases. As described above, when the air expands due to a change in the surrounding environment, if the ventilation holes 15b and 15c, the wedge-shaped gap portion 19a, and the annular groove portion 20 are not provided, as in the conventional example shown in FIG. The oil is pushed out from the rotary shaft support by the amount of air expansion. On the other hand, in the fluid bearing mechanism and the motor of the present embodiment, the ventilation holes 15b and 15c communicate the annular groove 20 with the radial thrust gap 12 and the radial radial gap 11 respectively, and the ventilation holes 15b and 15c are formed. A wedge-shaped gap portion 19a connected to a position different from the position communicates the annular groove portion 20 with the outside of the base 3. For this reason, in the fluid bearing mechanism and the motor of this embodiment, even if the sealed air expands, the pressure of the expanded air is released by the ventilation holes 15b and 15c, the annular groove 20, and the wedge-shaped gap 19a. Can be. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Further, in the hydrodynamic bearing mechanism and the motor according to the present embodiment, for example, when extremely strong vibration is applied from the outside, the oil flows into the ventilation holes 15b,
There is a possibility that the oil leaks into the annular groove 20 through the groove 15c. However, the wedge-shaped gap 19a and the ventilation holes 15b,
15c are arranged on the annular groove 20 at different phases from each other, so that the oil does not leak outside through the wedge-shaped gap 19a, and the oil is stored in the annular groove 20.

As described above, the hydrodynamic bearing mechanism of this embodiment
In the motor equipped with the fluid bearing mechanism, the ventilation holes 15b and 15c, which are the first communication portions, are formed by the annular groove 20 and the radial thrust gap 12 and the radial gap 1.
1 is connected to each other. Further, the wedge-shaped gap portion 19a, which is the second communication portion, is formed on the annular groove portion 20 by the ventilation hole 15a.
b, 15c and is connected to a position different from that of the annular groove 2
0 and the outside of the motor. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

<Twelfth Embodiment> FIG. 17 is a sectional view showing the structure of a fluid bearing mechanism according to a twelfth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. FIG.
(A) and (b) of FIG. 18 are a side view showing the configuration of the sleeve 18a shown in FIG.
FIG. 19B is a bottom view as seen from 7b, and FIG.
8 (d) is a side view showing the configuration of the sleeve 18b shown in FIG. 17 and a bottom view seen from the thrust flange 8. FIG. In this embodiment, in the configuration of the hydrodynamic bearing mechanism, a plurality of sleeves divided in the axial direction are provided with a wedge-shaped gap portion, and the outside and the inside of the rotary shaft support portion are formed using the wedge-shaped gap portion and the annular groove portion. Communicated. The other parts are the same as those of the tenth embodiment, and the duplicated description thereof will be omitted.

As shown in FIGS. 17 and 18 (a) to 18 (d), in the hydrodynamic bearing mechanism of the present embodiment, the base 3 has cylindrical sleeves 18a and 18b and the sleeves 18a and 18b. Sleeve holding member 3 holding 18b
8 is provided. A radial bearing 7a is provided on an inner peripheral portion of the sleeve 18a, and a radial bearing 7b is provided on an inner peripheral portion of the sleeve 18b. Sleeve 1
Chamfers 21a and 21b are provided on the outer peripheral portions of 8a and 18b, respectively. Thereby, the sleeve 18
When the a and 18b are arranged in the sleeve holding member 38 in a two-tiered manner, the annular groove 20
8 is formed. Also, the sleeves 18a, 18b
Are provided with a plurality of, for example, three wedge-shaped
a and 19b are formed by a rolling method. On the bottom surface of the sleeve 18a on the side of the sleeve 18b, a plurality of, for example, three wedge-shaped gap portions 19c are formed by a rolling method. These wedge-shaped gaps 19
a, 19b and 19c are arranged at equal intervals on the concentric circumference of the rotating shaft 2. Each of the wedge-shaped gap portions 19a, 19c is formed so as to become wider toward the outside of the sleeve 18a. Similarly, each wedge-shaped gap portion 19b is formed so as to become wider toward the outside of the sleeve 18b.

Each wedge-shaped gap portion 19a constitutes a second communication portion, and communicates the outside of the base 3 with the annular groove portion 20. Each wedge-shaped gap portion 19b constitutes a first communication portion, and connects the annular groove portion 20 and the radial thrust interspace portion 12. Similarly, each wedge-shaped gap portion 19c constitutes a first communication portion, and connects the annular groove portion 20 and the radial gap portion 11. The above-described first and second communication portions are arranged in the annular groove 20 at different phases. Specifically, the wedge-shaped gaps 19b and 19c and the wedge-shaped gap 19a are connected to different positions of the annular groove 20 without being directly connected. Thus, in the fluid bearing mechanism of the present embodiment, as in the case of the tenth embodiment, even if extremely strong vibration is applied, it is possible to prevent oil from being scattered outside the motor.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor of the present embodiment will be described with reference to FIG. In the following description, the wedge-shaped gap portions 19a,
Only the functions of the annular grooves 19b and 19c and the annular groove 20 will be described. In FIG. 17, when the motor is assembled, the air sealed in the rotating shaft bearing portion is caused by changes in the surrounding environment,
For example, when conveyed by an aircraft or the like, it expands with a decrease in the surrounding atmospheric pressure. As described above, when the air expands due to a change in the surrounding environment, the wedge-shaped gap portions 19a, 19b, 19
In the case where c and the annular groove portion 20 are not provided, the oil is pushed out from the rotary shaft supporting portion by the amount of the expansion of the air as in the conventional example shown in FIG. On the other hand, in the hydrodynamic bearing mechanism and the motor of the present embodiment, the wedge-shaped
b and 19c communicate the annular groove 20 with the radial thrust gap 12 and the radial gap 11, respectively;
A wedge-shaped gap 19a connected to a different position from the wedge-shaped gaps 19b and 19c communicates the annular groove 20 with the outside of the base 3. For this reason, in the fluid bearing mechanism and the motor of the present embodiment, even if the sealed air expands, the pressure of the expanded air is released by the wedge-shaped gap portions 19b and 19c, the annular groove portion 20, and the wedge-shaped gap portion 19a. be able to. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Furthermore, in the hydrodynamic bearing mechanism and the motor according to the present embodiment, for example, when extremely strong vibration is applied from the outside, the oil is removed from the wedge-shaped gap portion 19.
There is a possibility of leaking into the annular groove 20 along the b and 19c. However, the wedge-shaped gap 19a and the wedge-shaped gap 1
Since the grooves 9b and 19c are arranged in different phases on the annular groove 20, the oil does not leak to the outside along the wedge-shaped gap 19a, and the oil is stored in the annular groove 20.

As described above, the hydrodynamic bearing mechanism of this embodiment
In the motor equipped with the fluid bearing mechanism, the wedge-shaped gap portions 19b and 19c as the first communication portions are formed in the annular groove portions 20.
And the radial gap 12 between radial thrusts and the radial gap 11. Further, a wedge-shaped gap portion 19a, which is a second communication portion, is connected to a position different from the wedge-shaped gap portions 19b and 19c on the annular groove portion 20, and communicates the annular groove portion 20 with the outside of the motor. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

<< Thirteenth Embodiment >> FIG. 19 is a sectional view showing the structure of a fluid bearing mechanism according to a thirteenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. FIG.
(A) of FIG. 20 is a bottom view showing the configuration of the sleeve as viewed from the thrust flange shown in FIG. 19. (B) of FIG.
20A is a cross-sectional view showing the configuration of the sleeve taken along the line AOB of FIG. 20A, and FIG.
It is sectional drawing which shows the structure of the sleeve which took the cross section by the OC line. In this embodiment, in the configuration of the hydrodynamic bearing mechanism,
Instead of the ventilation holes provided in the sleeve and the sleeve holding member, wedge-shaped gap portions are provided in the sleeve as first and second communication portions. The other parts are the same as those of the tenth embodiment, and the duplicated description thereof will be omitted. FIG.
As shown in FIGS. 9 and 20 (a) to 20 (c), in the hydrodynamic bearing mechanism of the present embodiment, the base 3 has a cylindrical sleeve 18, and a sleeve holding member 38 which holds the sleeve 18. Is provided. These sleeves 1
8 and the sleeve holding member 38, the annular groove 20
Are formed. Radial bearings 7a and 7b are provided on the inner peripheral portion of the sleeve 18. The sleeve 18 is provided with a ventilation hole 22 as a first communication portion, and communicates the annular groove portion 20 with the radial gap 11.

A plurality of, for example, three wedge-shaped gap portions 19a and 19b are formed on the outer peripheral portion of the sleeve 18 by a rolling method. These wedge-shaped gaps 19
a and 19b are arranged at equal intervals on the concentric circumference of the rotating shaft 2. Each wedge-shaped gap portion 19a, 19b is
Is formed so as to become wider toward the outside. Each wedge-shaped gap portion 19a constitutes a second communication portion,
The outside of the base 3 communicates with the annular groove 20. Each wedge-shaped gap portion 19b constitutes a first communication portion, and connects the annular groove portion 20 and the radial thrust interspace portion 12. The above-described first and second communication portions are arranged in the annular groove 20 at different phases. Specifically, the wedge-shaped gap portion 19b and the ventilation hole 22 and the wedge-shaped gap portion 19a are connected to different positions of the annular groove portion 20 without being directly connected. This allows
In the hydrodynamic bearing mechanism of this embodiment, as in the case of the tenth embodiment, even if extremely strong vibration is applied, it is possible to prevent oil from being scattered outside the motor.

Hereinafter, the operation of the hydrodynamic bearing mechanism and the motor according to the present embodiment will be described with reference to FIG. In the following description, the wedge-shaped gap portions 19a,
Only the functions of the groove 19b, the annular groove 20, and the ventilation hole 22 will be described. In FIG. 19, when the motor is assembled, the air sealed in the rotating shaft bearing expands with a change in the surrounding environment, for example, when the air is conveyed by an aircraft or the like, as the surrounding air pressure decreases. As described above, when the air expands due to a change in the surrounding environment, the wedge-shaped gap portions 19a, 19b,
When the annular groove 20 and the ventilation hole 22 are not provided,
As in the case of the conventional example shown in FIG. 23, the oil is pushed out from the rotary shaft support by the amount of expansion of the air. On the other hand, in the hydrodynamic bearing mechanism and the motor of the present embodiment, the wedge-shaped gap 19b and the ventilation hole 22 communicate the annular groove 20 with the radial thrust gap 12 and the radial gap 11, respectively. Portion 19b and the wedge-shaped gap portion 19a connected to a position different from the ventilation hole 22 have an annular groove portion 20.
And the outside of the base 3. For this reason, in the fluid bearing mechanism and the motor of the present embodiment, even if the sealed air expands, the pressure of the expanded air is reduced by the wedge-shaped gap portion 19b.
And vent hole 22, annular groove 20, and wedge-shaped gap 19
It can be escaped by a. As a result, in the fluid bearing mechanism and the motor according to the present embodiment, it is possible to suppress the expanded air from pushing out the oil from the bearing gap. Furthermore, in the fluid bearing mechanism and the motor of the present embodiment, for example, when extremely strong vibration is applied from the outside, oil may leak to the annular groove 20 through the wedge-shaped gap 19b and the ventilation hole 22. However, the wedge-shaped gap 19a and the wedge-shaped gap 19b and the ventilation hole 2
2 are arranged in different phases on the annular groove 20, so that the oil does not leak to the outside through the wedge-shaped gap 19 a, and the oil is stored in the annular groove 20.

As described above, the hydrodynamic bearing mechanism of this embodiment
In the motor equipped with the fluid bearing mechanism, the wedge-shaped gap portion 19b and the ventilation hole 22, which are the first communication portions, respectively communicate the annular groove portion 20, the radial thrust gap 12, and the radial gap 11. ing. Furthermore, the second
Is connected to the annular groove 20 at a position different from that of the wedge-shaped gap 19b and the ventilation hole 22, and communicates the annular groove 20 with the outside of the motor. Accordingly, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, even when the air sealed in the rotating shaft support expands due to a change in the surrounding environment, the oil is externally transmitted from the rotating shaft support. Can be prevented from leaking. Furthermore, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, oil can be prevented from leaking out of the motor, so that contamination by the leaked oil can be prevented.

Fourteenth Embodiment FIG. 21 is a sectional view showing the structure of a fluid bearing mechanism according to a fourteenth embodiment of the present invention, and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, an oil absorbing member for adsorbing and absorbing oil leaked from the open end of the rotary shaft support between the rotor and the rotary shaft support is provided. In the following description, for the sake of simplicity, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description will be omitted. In FIG. 21, in the fluid dynamic bearing mechanism of the present embodiment, a stator core 31 made of soft magnetic sintered ferrite is arranged between the rotor and the rotary shaft bearing. The stator core 31 not only forms a magnetic circuit for rotating the rotor, but also includes an oil absorbing member that adsorbs and leaks oil leaked from the open end of the base 3 between the rotor and the base 3. I also use it. More specifically, the stator core 31 is provided with the magnet 5 included in the rotor.
Are fixed on the outer cylindrical surface of the base 3 within the inner cylindrical surface of the hub 1 of the rotor with a predetermined gap therebetween. The soft magnetic sintered ferrite constituting the stator core 31 includes:
There are countless minute holes on the surface (not shown). For this reason, in the fluid bearing mechanism of this embodiment, the leaked oil can be adsorbed and absorbed by the minute holes of the stator core 31, and the oil can be prevented from being scattered outside the motor.

More specifically, oil is applied to the radial bearing portion 7 by external force due to vibration or impact and changes in the surrounding environment.
a, and leaks out onto the open end of the base 3, and becomes mist-like by the rotation of the rotating shaft 2 and the rotor.
Attempt to diffuse outside through a gap between the magnet and the magnet 5.
On the other hand, in the hydrodynamic bearing mechanism of the present embodiment, the stator core 31 is formed using soft magnetic sintered ferrite having minute holes on the surface. Therefore, in the fluid bearing mechanism of the present embodiment, when the mist oil passes through the above-described gap due to the airflow generated by the rotation in the inner peripheral cylindrical surface of the hub 1 (rotor), the minute Adsorption and absorption by the holes and scattering to the outside of the motor can be suppressed. Further, in the motor equipped with the hydrodynamic bearing mechanism of the present embodiment, as a secondary effect due to the use of the soft magnetic sintered ferrite, the eddy current loss can be reduced to almost zero, and the hard disk required to rotate at high speed is required. In an apparatus motor or the like, low power consumption and downsizing of the motor can be easily performed.

As described above, the hydrodynamic bearing mechanism of this embodiment
Further, in a motor equipped with the fluid bearing mechanism, the stator core 31 is formed of soft magnetic sintered ferrite having minute holes on the surface. Further, the stator core 31 is fixed on the outer cylindrical surface of the base 3 within the inner cylindrical surface of the hub 1 of the rotor with a predetermined gap between the stator core 31 and the magnet 5 included in the rotor. As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, it is possible to adsorb and absorb the oil atomized by the rotation of the rotor by the minute holes of the stator core 31, It is possible to suppress the oil leaking from the rotating shaft bearing from scattering to the outside of the motor.

<< Fifteenth Embodiment >> FIG. 22 is a sectional view showing the structure of a fluid bearing mechanism according to a fifteenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism. In this embodiment, in the configuration of the fluid bearing mechanism, a filter member is provided on the rotary shaft support in the inner peripheral cylindrical surface of the rotor instead of using a soft magnetic sintered ferrite to configure the stator core. The other parts are the same as those of the fourteenth embodiment, and the duplicated description thereof will be omitted. FIG.
As shown in (1), in the hydrodynamic bearing mechanism of the present embodiment, the mesh filter member 32 is disposed on the base 3 within the inner peripheral cylindrical surface of the hub 1. The filter member 32 is preferably formed in an annular or arc shape using a fiber material such as PET or a porous thermoplastic resin material having a large number of holes. Specifically, the filter member 32 is fixed around the outer peripheral cylindrical surface of the base 3 below the magnet 5, the yoke 6, and the stator core 30 so as to close the gap between the hub 1 and the base 3. This allows
In the fluid bearing mechanism of the present embodiment, the leaked oil can be absorbed and absorbed by the filter member 32, and the oil can be prevented from scattering outside the motor. In addition, since the airflow turns inside the hub 1, the filter member 32 does not have to be annular, and may have a fan shape with an opening angle of about 50 ° to 90 °, for example.

More specifically, oil is applied to the radial bearing portion 7 by external force due to vibration or impact and changes in the surrounding environment.
a, and leaks onto the open end of the base 3 to form a mist by the rotation of the rotating shaft 2 and the rotor.
And tries to diffuse to the outside through the gap. On the other hand, in the fluid bearing mechanism of the present embodiment, the filter member 32 is disposed on the base 3 within the inner peripheral cylindrical surface of the hub 1 so as to close the gap. Therefore, in the fluid bearing mechanism of the present embodiment, when the mist oil passes through the above-described gap by the airflow generated by the rotation in the inner peripheral cylindrical surface of the hub 1 (rotor), it is adsorbed by the filter member 32. Absorbed,
It is possible to suppress scattering to the outside of the motor.

As described above, the hydrodynamic bearing mechanism of this embodiment
In a motor equipped with the fluid bearing mechanism, the filter member 32 is disposed on the base 3 within the inner peripheral cylindrical surface of the hub 1 so as to close the gap between the hub 1 and the base 3. As a result, in the fluid bearing mechanism of the present embodiment and the motor equipped with the fluid bearing mechanism, the oil atomized by the rotation of the rotor can be adsorbed and absorbed by the filter member 32, and the rotating shaft support portion Oil that has leaked out of the motor can be suppressed from scattering outside the motor. The shape of the filter member 32 is not limited to an arc shape, but absorbs mist-like oil carried by an air current generated by rotation of the rotor in a gap between the rotor and the rotation shaft bearing. Any shape can be used as long as it can be formed.

In the above-described first to fifteenth embodiments, the structure in which the thrust flange is fixed to the rotary shaft by a screw has been described. In addition, a stepped shaft in which the rotary shaft and the thrust flange are integrally formed. May be used. Further, in the seventh to thirteenth embodiments, the example in which the wedge-shaped gap is provided on the outer peripheral portion of the sleeve has been described. The portion may be provided on the sleeve holding member by notching. Further, the oil absorbing member is not limited to those described in the fourteenth and fifteenth embodiments described above, and the rotation of the rotor in the gap between the rotor and the rotating shaft support portion. What is necessary is just to be able to adsorb and absorb the oil in the airflow generated by the above. For example, a configuration may be adopted in which a ring made of a sintered alloy having a large number of holes is bonded on the cylindrical surface of the magnet facing the stator core. Further, the hydrodynamic bearing mechanism and the motor may be configured by appropriately combining the first to fifteenth embodiments.

[0079]

The hydrodynamic bearing mechanism of the present invention and the motor equipped with the hydrodynamic bearing mechanism rotate integrally with the rotor,
In addition, an oil sealing portion is provided at an open end of the rotating shaft support portion so as to be opposed to the opening end portion via a predetermined gap. Further, a spiral groove portion is formed in the oil sealing portion so that the oil leaked into the gap moves to the rotation shaft support portion side as the rotor rotates. In the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, even if oil leaks from the rotating shaft support portion due to external exciting force or impact force due to vibration or impact, the oil sealing portion The oil moves in the sealing direction again without scattering the oil leaked by the rotation of the rotor to the outside of the motor. As a result, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, it is possible to prevent the oil from running short on the rotary shaft support. Further, the oil can be prevented from being scattered to the outside of the motor, so that contamination due to the scattered oil can be prevented. For example, even when the oil is built in a hard disk device, data cannot be read due to the adhesion of the scattered oil.

Further, in the fluid bearing mechanism according to another aspect of the present invention and the motor equipped with the fluid bearing mechanism, the outside of the rotary shaft supporting portion and the radial thrust formed between the radial bearing means and the thrust bearing means are provided. There is provided a communication portion that communicates with at least one of the gaps and the radial gap formed between the radial bearing means.
Further, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, an oil repellent is applied to at least the inner surface of the communication portion on the side of the gap. This allows
In the fluid bearing mechanism and the motor equipped with the fluid bearing mechanism of the present invention, even if the surrounding environment changes, oil is prevented from leaking out of the rotary shaft support, and the oil is scattered outside the motor. Can be prevented.

According to another aspect of the present invention, there is provided a fluid bearing mechanism according to the present invention and a motor having the fluid bearing mechanism mounted thereon. And a communicating portion that communicates with at least one of the inter-radial gap formed between the gap and the radial bearing means. Further, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, the communicating portion is provided on the sleeve or the sleeve holding member, and is formed in a wedge shape so as to widen toward the outside. Thus, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, even if the surrounding environment changes, oil is prevented from leaking out of the rotary shaft support, and the oil is externally provided to the motor. Can be prevented from scattering.

According to another aspect of the present invention, there is provided a hydrodynamic bearing mechanism according to the present invention and a motor having the hydrodynamic bearing mechanism mounted thereon, the annular groove portion, a radial thrust gap formed between the radial bearing means and the thrust bearing means, and A first communication portion is provided for communicating with at least one of the radial gaps formed between the radial bearing means. Further, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, the second communication portion is connected to the annular groove at a position different from the first communication portion, and communicates with the annular groove and the outside. And Thereby, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, even if oil leaks from the rotating shaft support portion, the oil does not scatter to the outside of the motor, and the oil is applied to the rotating shaft support portion. Oil can be returned.

A fluid bearing mechanism according to another aspect of the present invention and a motor equipped with the fluid bearing mechanism are provided between a rotor and a rotating shaft support, and leak from an open end of the rotating shaft support. An oil absorbing member for absorbing oil. Further, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, the oil absorbing member has the oil in the airflow generated by the rotation of the rotor in the gap between the rotor and the rotating shaft support. Is adsorbed and absorbed. As a result, in the fluid bearing mechanism of the present invention and the motor equipped with the fluid bearing mechanism, even if the fluid leaks out of the rotary shaft support, it can be prevented from scattering outside the motor.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a fluid bearing mechanism according to a first embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 2 is an enlarged cross-sectional view showing a detailed configuration of a hydrodynamic bearing mechanism near a radial scraping member shown in FIG.

FIG. 3 is an explanatory view showing a configuration and a function of the radial scraping member shown in FIG. 1;

FIG. 4 is a sectional view showing the configuration of a fluid bearing mechanism according to a second embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 5 is a perspective view showing the configuration and function of the thrust scraping member shown in FIG. 4;

FIG. 6 is a sectional view showing the configuration of a fluid bearing mechanism according to a third embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 7 is a cross-sectional view illustrating a configuration of a fluid bearing mechanism according to a fourth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 8 is a sectional view showing a configuration of a fluid bearing mechanism according to a fifth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

9 is an enlarged cross-sectional view showing a configuration of a portion surrounded by a dashed line T in FIG. 8;

FIG. 10 shows a hydrodynamic bearing mechanism according to a sixth embodiment of the present invention;
Sectional view showing the configuration of a motor equipped with the fluid bearing mechanism

11 is a cross-sectional view showing a modification of the fluid bearing mechanism shown in FIG. 10 and a configuration of a motor equipped with the fluid bearing mechanism.

FIG. 12 shows a hydrodynamic bearing mechanism according to a seventh embodiment of the present invention;
Sectional view showing the configuration of a motor equipped with the fluid bearing mechanism

FIG. 13 shows a hydrodynamic bearing mechanism according to an eighth embodiment of the present invention;
Sectional view showing the configuration of a motor equipped with the fluid bearing mechanism

FIG. 14 shows a hydrodynamic bearing mechanism according to a ninth embodiment of the present invention;
Sectional view showing the configuration of a motor equipped with the fluid bearing mechanism

FIG. 15 is a sectional view showing the configuration of a fluid bearing mechanism according to a tenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 16 is a sectional view showing the configuration of a fluid bearing mechanism according to an eleventh embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 17 is a sectional view showing the configuration of a fluid bearing mechanism according to a twelfth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

18 is a structural diagram showing a detailed configuration of the sleeve shown in FIG.

FIG. 19 is a sectional view showing the configuration of a fluid bearing mechanism according to a thirteenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 20 is a structural diagram showing a detailed configuration of the sleeve shown in FIG. 19;

FIG. 21 is a sectional view showing the configuration of a fluid bearing mechanism according to a fourteenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 22 is a sectional view showing the configuration of a fluid bearing mechanism according to a fifteenth embodiment of the present invention and a motor equipped with the fluid bearing mechanism.

FIG. 23 is a sectional view showing a configuration of a conventional fluid bearing mechanism and a conventional motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hub 2 Rotation shaft 3 Base 5 Magnet 6 Yoke 7a, 7b Radial bearing part 8 Thrust flange 9 Thrust plate 11 Radial gap 12 Radial thrust gap 13, 17, 17 ', 23 Oil sealing part 14, 14' , 14a, 14b Sleeve 15, 15a, 15b, 15c Ventilation hole 16, 16 ', 18, 18a, 18b, Sleeve 19a, 19b, 19c Wedge-shaped gap 20 Ring-shaped groove 24 Rotary shaft taper 25 Oil repellent 31 Stator core 32 mesh Filter member 40 Open end gap

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masafumi Omura 1006 Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 72) Inventor Takumichi Inomata 1006, Kazuma, Kazuma, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. BB22 BB40 5H605 AA02 BB05 BB15 BB19 CC01 CC02 CC04 EB03 EB06 EB28 EB31 5H607 AA05 BB01 BB14 BB17 BB27 CC01 DD02 DD08 FF12 GG01 GG02 GG09 GG12 GG28 KK03

Claims (14)

[Claims] A rotary shaft rotating in one direction; a predetermined gap formed between the rotary shaft and the rotary shaft filled with oil; and a radial bearing means for rotatably supporting the rotary shaft by the oil dynamic pressure. And a thrust bearing means, a rotating shaft bearing having a closed end and an open end at one end and the other end, respectively, a rotor that rotates integrally with the rotating shaft, and integrally with the rotor. Rotating, and disposed opposite to the open end of the rotary shaft support portion via a predetermined gap, provided with an oil sealing portion having a spiral groove portion on the opposed arrangement surface, the oil leaking into the gap, The fluid bearing mechanism, wherein the helical groove is formed so as to move toward the rotation shaft supporting part as the rotor rotates. 2. The hydrodynamic bearing mechanism according to claim 1, wherein the spiral groove portion of the oil sealing portion is disposed on a plane perpendicular to the rotation axis. 3. The hydrodynamic bearing mechanism according to claim 1, wherein the spiral groove portion of the oil sealing portion is disposed on a cylindrical surface coaxial with the rotation axis. 4. The hydrodynamic bearing mechanism according to claim 1, wherein the spiral groove of the oil sealing portion is disposed on a plane perpendicular to the rotation axis and on a coaxial cylindrical surface. 5. The hydrodynamic bearing mechanism according to claim 1, wherein the spiral groove of the oil sealing portion is disposed on a conical surface coaxial with the rotation axis. 6. The rotary shaft according to claim 1, wherein said rotary shaft is provided with a rotary shaft taper portion formed in a tapered shape such that a diameter of said rotary shaft increases toward said rotary shaft support portion. 6. The hydrodynamic bearing mechanism according to any one of 5. 7. A rotary shaft that rotates in one direction, and a predetermined gap formed between the rotary shaft and the rotary shaft is filled with oil, and radial bearing means rotatably supports the rotary shaft by the oil dynamic pressure. Between the radial bearing means and the thrust bearing means, and between the radial bearing means and the radial thrust gap formed between the radial bearing means and the thrust bearing means, and between the outside of the rotating shaft bearing part and the radial bearing means. A communication portion that communicates with at least one of the formed radial inter-gap portions; an oil repellent is applied to at least an inner surface of the communication portion on the side of the gap portion, and air in the gap portion is released to the outside A fluid bearing mechanism, characterized in that: 8. A rotating shaft that rotates in one direction, at least one sleeve, and a sleeve holding member that fits and holds the sleeve, and supplies oil to a predetermined gap formed between the rotating shaft and the sleeve. A rotating shaft supporting part comprising a radial bearing means and a thrust bearing means for rotatably supporting the rotating shaft by the oil dynamic pressure of the filling, an outer part of the rotating shaft supporting part, the radial bearing means and the thrust A communication portion communicating between at least one of the radial thrust gap formed between the bearing means and the radial gap formed between the radial bearing means; and wherein the communication portion is the sleeve. Alternatively, the fluid bearing mechanism is provided on the sleeve holding member, and is formed in a wedge shape so that a cross-sectional shape thereof becomes wider toward the outside. 9. A rotary shaft that rotates in one direction, at least one sleeve, and a sleeve holding member that fits and holds the sleeve, and supplies oil to a predetermined gap formed between the rotary shaft and the sleeve. A rotating shaft supporting portion comprising a radial bearing means and a thrust bearing means for rotatably supporting the rotating shaft by the oil dynamic pressure after being filled, an annular groove provided between the sleeve and the sleeve holding member, The annular groove communicates with at least one of a radial thrust gap formed between the radial bearing means and the thrust bearing means and a radial gap formed between the radial bearing means. A first communicating portion that is connected to the annular groove at a position different from the first communicating portion, and a second communicating portion that communicates with the annular groove and the outside.
A fluid bearing mechanism, comprising: 10. The hydrodynamic bearing mechanism according to claim 9, wherein at least one of the first and second communication portions is formed in a wedge shape so that a cross-sectional shape thereof becomes wider toward the outside. 11. A rotary shaft that rotates in one direction, and a predetermined gap formed between the rotary shaft and the rotary shaft is filled with oil, and radial bearing means rotatably supports the rotary shaft by the oil dynamic pressure. And a thrust bearing means, a rotating shaft that rotates integrally with the rotating shaft, and a rotor provided between the rotor and the rotating shaft supporting portion, from an open end of the rotating shaft supporting portion. An oil absorbing member that absorbs leaked oil, wherein the oil absorbing member adsorbs oil in an air current generated by rotation of the rotor in a gap between the rotor and the rotating shaft support. A fluid bearing mechanism characterized by being configured to absorb. 12. The stator according to claim 11, wherein a stator core disposed between the rotor and the rotation shaft bearing is made of soft magnetic sintered ferrite, and also serves as the oil absorbing member. Fluid bearing mechanism. 13. The method according to claim 13, wherein the oil absorbing member is constituted by a filter member provided on the rotating shaft support portion or on the inner cylindrical surface of the rotor in the inner cylindrical surface of the rotor. The hydrodynamic bearing mechanism according to claim 11, wherein 14. A motor equipped with the hydrodynamic bearing mechanism according to claim 1.