JP2004176778A - Dynamic pressure bearing device, method of manufacturing the same, and motor using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a specified fixing strength by stabilizing the fixed state of a housing to a holding member. <P>SOLUTION: The fixed surface 7d of the housing comprises a deformation area 7d2 deformed by a specified amount to the outer diameter side according to the press-fitting of a thrust member thereto and the other area 7d1. The deformation area 7d2 has a tapered shape gradually reducing in diameter to the lower side thereof, and is moved backward to the inner diameter side relative to the other area 7d1 by an amount equivalent to the deformation amount according to the press-fitting of a thrust member 10. When the thrust member 10 is press-fitted to the inner periphery of a press-fitted part 7b1, the fixed face 7d of the housing 7 is formed in an axially substantially straight shape over the axially entire area L. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a dynamic pressure bearing device that rotatably supports a shaft member in a non-contact manner by dynamic pressure action of lubricating oil generated in a bearing gap, a method of manufacturing the same, and a motor using the same. This bearing device is a spindle for information equipment, for example, a magnetic disk device such as an HDD or FDD, an optical disk device such as a CD-ROM, a CD-R / RW, a DVD-ROM / RAM, or a magneto-optical disk device such as an MD or MO. It is suitable for a motor, a polygon scanner motor of a laser beam printer (LBP), or a small motor such as an electric device such as an axial fan.
[0002]
[Prior art]
The above various motors are required to have high speed, low cost, low noise, etc. in addition to high rotational accuracy. One of the components that determine these required performances is a bearing that supports the spindle of the motor, and in recent years, as this type of bearing, the use of a dynamic pressure bearing having characteristics excellent in the required performance has been studied. Or it is actually used.
[0003]
For example, in a hydrodynamic bearing device incorporated in a spindle motor of a disk drive device such as an HDD, a radial bearing portion that rotatably supports a shaft member in a radial direction in a non-contact manner, and a non-contact support rotatably supports a shaft member in a thrust direction. A thrust bearing portion is provided, and as the radial bearing portion, a dynamic pressure bearing in which a groove (dynamic pressure groove) for generating dynamic pressure is provided on the inner peripheral surface of the bearing sleeve or the outer peripheral surface of the shaft member is used. As the thrust bearing portion, for example, a dynamic pressure groove provided on both end surfaces of a flange portion of a shaft member or a surface opposed thereto (an end surface of a bearing sleeve, an end surface of a thrust member fixed to a housing, or the like). A pressure bearing is used (for example, see Patent Document 1).
[0004]
Usually, the bearing sleeve is fixed to the inner circumference of the housing, and the thrust member is fixed to the inner circumference of one end of the housing. Further, in order to prevent the lubricating oil injected into the internal space of the housing from leaking outside, a seal portion is often provided at the other end of the housing.
[0005]
[Patent Document 1]
JP-A-2002-061641
[Problems to be solved by the invention]
In such a dynamic pressure bearing device, press-fitting may be employed as a means for fixing the thrust member to the inner periphery of one end of the housing. Further, after the thrust member is press-fitted, the press-fitted portion may be filled with an adhesive from the outside of the housing, and the press-fitted portion may be sealed with the adhesive. However, with the press-fitting of the thrust member, a predetermined area on the outer periphery of the housing expands and deforms toward the outer diameter side, and the following problem may occur.
[0007]
For example, when this kind of dynamic pressure bearing device is used for the rotation supporting portion of the above-mentioned various motors, the outer periphery of the housing is usually fixed closely to the inner periphery of the bracket (holding member) via an adhesive. In consideration of the strength, the axial dimension of the bonded portion and the filling gap of the adhesive are determined. However, when the thrust member is press-fitted and a part of the bonding surface (fixed surface) on the outer periphery of the housing undergoes expansion deformation, the gap filled with the adhesive in the axial direction when mounted on the inner periphery of the holding member is not sufficient. There is a concern that uniformity will occur, and that the bonding strength will decrease and resonance will occur.
[0008]
It is also conceivable that the outer periphery of the housing is tightly fixed to the inner periphery of the bracket (holding member) by press-fitting. When expansion deformation occurs in the holding member, the interference becomes uneven in the axial direction when it is press-fitted into the inner periphery of the holding member, and there is a concern that the press-fitting strength is reduced and a problem of resonance occurs.
[0009]
An object of the present invention is to solve the above-described problem caused by the expansion and deformation of the fixing surface on the outer periphery of the housing, stabilize the fixing state between the housing and the holding member, and obtain a desired fixing strength.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a housing, a bearing sleeve fixed to an inner periphery of the housing, a shaft member having a shaft and a flange, a thrust member fixed to one end of the housing, and a bearing. A radial bearing portion provided between the sleeve and the shaft portion and supporting the shaft portion in a non-contact manner in the radial direction by the dynamic pressure action of the lubricating oil generated in the radial bearing gap, and between the bearing sleeve and the thrust member and the flange portion. A thrust member provided at one end of the housing, the thrust member being provided at a first end of the housing. The housing is press-fitted into the inner periphery of the press-fitting portion with a predetermined interference, and the housing has a predetermined axial dimension on its outer periphery and is fixedly fixed to the inner periphery of the holding member. The fixing surface has a deformation area that is deformed by a predetermined amount toward the outer diameter side with the press-fit of the thrust member, and is substantially straight in the axial direction over the entire axial direction in a state where the thrust member is press-fitted. A configuration having a simple shape is provided.
[0011]
Here, the “substantially straight shape in the axial direction” includes not only a shape in which the fixing surface has the same diameter over the entire region in the axial direction (completely straight shape), but also all or a part of the deformation region of the fixing surface. For example, a shape (substantially straight shape) having a radius difference within a range of −30 μm or more and +5 μm or less with respect to an area other than the deformation area is included.
[0012]
According to the above configuration, in a state where the thrust member is pressed into the press-fitting portion of the housing, the fixing surface of the housing has a substantially straight shape in the axial direction over the entire region in the axial direction. When closely fixed to the periphery, the fixing state is stable, and a desired fixing strength can be obtained.
[0013]
According to another aspect of the present invention, there is provided a housing, a bearing sleeve fixed to an inner periphery of the housing, a shaft member having a shaft and a flange, and a thrust member fixed to one end of the housing. A radial bearing portion provided between the bearing sleeve and the shaft portion and supporting the shaft portion in a non-contact manner in the radial direction by the dynamic pressure action of the lubricating oil generated in the radial bearing gap; and the bearing sleeve and the thrust member and the flange portion. A thrust bearing portion provided between the thrust bearing portion and supporting the flange portion in a non-contact manner in the thrust direction by a dynamic pressure action of the lubricating oil generated in the thrust bearing gap. A press-fit portion for press-fitting the member with a predetermined interference is formed, and has a predetermined axial dimension on the outer periphery of the housing, and is firmly fixed to the inner periphery of the holding member. Forming a surface, and deforming the fixed area, which is deformed by a predetermined amount to the outer diameter side with the press-fit of the thrust member, by an amount corresponding to the deformation amount to the inner diameter side with respect to the other area of the fixed surface. And the thrust member is press-fitted into the inner periphery of the press-fitting portion of the housing to be fixed.
[0014]
When the thrust member is press-fitted, the deformation area of the fixing face of the housing is retracted toward the inner diameter side with respect to the other area of the fixing face by an amount corresponding to the deformation amount accompanying the press-fitting of the thrust member. Since the surface has a substantially straight shape in the axial direction over the entire region in the axial direction, when the fixing surface is tightly fixed to the inner periphery of the holding member, the fixing state is stable, and a desired fixing strength can be obtained. .
[0015]
In the above configuration, as a means for tightly fixing the outer peripheral fixing surface to the inner periphery of the holding member, fixing with an adhesive, fixing by press fitting, or other appropriate fixing means can be adopted. In addition, a deformation region of the fixed surface of the housing can be provided adjacent to the other end of the press-fit portion of the housing, and the deformation region is formed in a tapered shape that gradually decreases in diameter toward one end of the housing. be able to.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0017]
FIG. 1 shows an example of a configuration of a spindle motor for information equipment incorporating a hydrodynamic bearing device 1 according to this embodiment. The spindle motor is used in a disk drive device such as an HDD, and includes a hydrodynamic bearing device 1 that rotatably supports a shaft member 2 in a non-contact manner, a rotor (disk hub) 3 mounted on the shaft member 2, For example, a stator 4 and a rotor magnet 5 are provided facing each other via a radial gap. The stator 4 is attached to the outer periphery of the bracket 6, and the rotor magnet 5 is attached to the inner periphery of the disk hub 3. The housing 7 of the hydrodynamic bearing device 1 is fixed to the inner periphery of the bracket 6 via an adhesive, for example. The disk hub 3 holds one or more disks D such as magnetic disks. When the stator 4 is energized, the rotor magnet 5 generates a rotating magnetic field in cooperation with the stator 4, whereby the disk hub 3 and the shaft member 2 rotate integrally.
[0018]
FIG. 2 shows the dynamic pressure bearing device 1. The hydrodynamic bearing device 1 includes a housing 7, a bearing sleeve 8 and a thrust member 10 fixed to the housing 7, and a shaft member 2.
[0019]
A first radial bearing portion R1 and a second radial bearing portion R2 are provided between the inner peripheral surface 8a of the bearing sleeve 8 and the outer peripheral surface 2a1 of the shaft portion 2a of the shaft member 2 so as to be separated in the axial direction. Further, a first thrust bearing portion S1 is provided between a lower end surface 8c of the bearing sleeve 8 and an upper end surface 2b1 of the flange portion 2b of the shaft member 2, and a first thrust bearing portion S1 is provided below the upper end surface 10a of the thrust member 10 and the flange portion 2b. A second thrust bearing portion S2 is provided between the second thrust bearing portion S2 and the end surface 2b2. For the sake of convenience, the description will be made with the side of the thrust member 10 being the lower side and the side opposite to the thrust member 10 being the upper side.
[0020]
The housing 7 is made of, for example, a soft metal material such as brass or a resin material such as a thermoplastic resin, and has a cylindrical side portion 7b and an annular seal portion 7a integrally extending from the upper end of the side portion 7b to the inner diameter side. And An inner peripheral surface 7a1 of the seal portion 7a faces a tapered surface 2a2 provided on an outer periphery of the shaft portion 2a via a predetermined seal space S. Further, a press-fitting portion 7b1 into which the thrust member 10 is press-fitted is formed at a lower end portion of the side portion 7b. The inner circumference of the press-fit portion 7b1 is larger in diameter than the inner peripheral surface 7c to which the bearing sleeve 8 is fixed, and the thickness of the press-fit portion 7b1 is smaller than the main portion of the side portion 7b. A fixing surface 7d having a predetermined axial dimension L is formed on the outer periphery of the housing 7.
[0021]
As shown in an enlarged manner in FIG. 6, the fixing surface 7d is located above the press-fitting portion 7b1, and is adjacent to the outer periphery of the press-fitting portion 7b1 via the step 7e. The fixing surface 7d has a substantially straight shape in the axial direction over the entire region L in the axial direction.
[0022]
FIG. 5 shows a state before the thrust member 10 is press-fitted into the press-fitting portion 7b1. The fixing surface 7d includes a deformation region 7d2 that deforms by a predetermined amount toward the outer diameter side with the press-fitting of the thrust member 10, and another region 7d1 (a region that does not expand and deform with the press-fitting of the thrust member 10). In this embodiment, the deformation region 7d2 has a tapered shape whose diameter gradually decreases downward, and is adjacent to the outer periphery of the press-fit portion 7b1 via the step portion 7e. Further, the deformation region 7d2 is retracted toward the inner diameter side with respect to the other region 7d1 by an amount corresponding to the deformation amount accompanying the press-fit of the thrust member 10. The dotted line in the right enlarged view of FIG. 5 indicates the position of the deformation area 7d2 after deformation, and the maximum retreat amount of the deformation area 7d2 is equal to the maximum deformation amount (radial amount) δ. Normally, the maximum deformation amount δ of the deformation region 7d2 is equal to or very close to the interference (radial amount) at the time of press-fitting of the thrust member 10, so the maximum retreat amount of the deformation region 7d2 is the press-fit of the thrust member 10. The design should be made to be equal to the interference (radial amount) at the time.
[0023]
The shaft member 2 is formed of, for example, a metal material such as stainless steel, and includes a shaft portion 2a and a flange portion 2b provided integrally or separately at a lower end of the shaft portion 2a. The tapered surface 2a2 of the shaft portion 2a gradually decreases in diameter toward the upper side (outside of the housing 7), and also functions as a centrifugal force seal by rotation of the shaft member 2.
[0024]
The bearing sleeve 8 is formed of, for example, a porous body made of a sintered metal, particularly a porous body of a sintered metal containing copper as a main component, and is formed in a cylindrical shape, and is fixed at a predetermined position on an inner peripheral surface 7c of the housing 7. .
[0025]
On the inner peripheral surface 8a of the bearing sleeve 8 formed of this sintered metal, two upper and lower regions serving as radial bearing surfaces of a first radial bearing portion R1 and a second radial bearing portion R2 are provided axially separated. In these two regions, for example, herringbone-shaped dynamic pressure grooves 8a1 and 8a2 as shown in FIG. The upper dynamic pressure groove 8a1 is formed asymmetrically in the axial direction with respect to the axial center m (the axial center of the region between the upper and lower inclined grooves), and the axial dimension X1 of the upper region is lower than the axial center m. It is larger than the axial dimension X2 of the side region. One or more axial grooves 8d1 are formed on the outer peripheral surface 8d of the bearing sleeve 8 over the entire length in the axial direction. In this example, three axial grooves 8d1 are formed at equal circumferential intervals. Further, chamfers 8e and 8f are formed at the outer peripheral corners of the upper end face 8b and the lower end face 8c, respectively.
[0026]
For example, a spiral dynamic pressure groove 8c1 as shown in FIG. 3B is formed on the lower end surface 8c of the bearing sleeve 8, which is the thrust bearing surface of the first thrust bearing portion S1. The shape of the dynamic pressure groove may be a herringbone shape, a radial groove shape, or the like.
[0027]
As shown in FIG. 3C, the upper end surface 8b of the bearing sleeve 8 is divided into an inner diameter side region 8b2 and an outer diameter side region 8b3 by a V-shaped cross-sectional circumferential groove 8b1 provided at a substantially central portion in the radial direction. One or more radial grooves 8b21 are formed in the divided inner diameter side region 8b2. In this example, three radial grooves 8b21 are formed at equal circumferential intervals.
[0028]
2, the inner surface 7a2 of the seal portion 7a is partially in contact with the inner diameter region 8b2 of the upper end surface 8b of the bearing sleeve 8 at its inner diameter region 7a21. The side region 7a22 is formed so as to be inclined or curved away from the upper end surface 8b of the bearing sleeve 8. Therefore, a slim part P having a required space volume is formed between the outer diameter side region 7a22 of the inner side surface 7a2 and the upper end surface 8b (including the chamfer 8e). The inner diameter side of the threaded portion P communicates with the circumferential groove 8b1, and the outer diameter side communicates with the axial groove 8d1.
[0029]
The thrust member 10 is formed of, for example, a metal material such as brass, and is press-fitted and fixed to the inner periphery of the press-fitting portion 7b1 of the housing 7. As shown in FIG. 4, for example, a herringbone-shaped dynamic pressure groove 10a1 is formed on the upper end surface 10a of the thrust member 10, which serves as the thrust bearing surface of the second thrust bearing portion S2. The dynamic pressure groove may have a spiral shape, a radial groove shape, or the like.
[0030]
The outer peripheral portion 10c of the thrust member 10 includes a press-fit surface 10c1 that is press-fitted into the inner periphery of the press-fit portion 7b1 of the housing 7, a tapered surface 10c2 that extends from the upper end of the press-fit surface 10c1 in the inclined direction toward the inner diameter side and reaches the upper end surface 10a. The tapered surface 10c3 extends from the lower end of the press-fit surface 10c1 in the inclined direction toward the inner diameter side and reaches the lower end surface 10b.
[0031]
The hydrodynamic bearing device 1 of this embodiment is assembled in, for example, the following steps.
[0032]
First, the bearing sleeve 8 is inserted into the inner peripheral surface 7c of the housing 7, and its upper end surface 8b is brought into contact with the inner surface 7a2 of the seal portion 7a. Thereby, the bearing sleeve 8 is positioned with respect to the housing 7. The fixing of the bearing sleeve 8 to the inner peripheral surface 7c of the housing 7 can be performed by press-fitting, bonding, a combination of press-fitting and bonding, or other appropriate fixing means.
[0033]
Next, the shaft member 2 is mounted on the bearing sleeve 8. Note that the inner diameter of the bearing sleeve 8 is measured in a state where the bearing sleeve 8 is fixed to the housing 7, and dimension matching with the outer diameter of the shaft portion 2a (measured in advance) is performed to reduce the radial bearing gap. It can be set with high accuracy.
[0034]
Thereafter, the thrust member 10 is press-fitted to the inner periphery of the press-fitting portion 7b1 of the housing 7 to a predetermined position and fixed. Since the deformation region 7d2 of the fixed surface 7d of the housing 7 is retracted toward the inner diameter side with respect to the other region 7d1 by an amount corresponding to the deformation amount accompanying the press-fitting of the thrust member 10 (see FIG. 5), the thrust member 10 is moved. When press-fitted, the fixing surface 7d of the housing 7 has a substantially straight shape in the axial direction over the entire region L in the axial direction (see FIG. 6). Therefore, when the fixing surface 7d of the housing 7 is fixed to the inner periphery of the bracket 6, the fixing state is stabilized, and a desired fixing strength can be obtained.
[0035]
When assembly is completed as described above, the shaft portion 2a of the shaft member 2 is inserted into the inner peripheral surface 8a of the bearing sleeve 8, and the flange portion 2b is connected to the lower end surface 8c of the bearing sleeve 8 and the upper end surface 10a of the thrust member 10. And is housed in the space between them. Thereafter, the internal space of the housing 7 sealed with the seal portion 7a is filled with a lubricating fluid, for example, lubricating oil, including the internal pores of the bearing sleeve 8. The oil level of the lubricating oil is maintained within the range of the seal space S.
[0036]
When the shaft member 2 rotates, the regions (two upper and lower regions) of the inner peripheral surface 8a of the bearing sleeve 8 to be radial bearing surfaces respectively oppose the outer peripheral surface 2a1 of the shaft portion 2a via the radial bearing gap. Further, the region of the lower end surface 8c of the bearing sleeve 8 that becomes the thrust bearing surface is opposed to the upper end surface 2b1 of the flange portion 2b via the thrust bearing gap, and the region that becomes the thrust bearing surface of the upper end surface 10a of the thrust member 10 is It faces the lower end surface 2b2 of the flange portion 2b via a thrust bearing gap. Then, with the rotation of the shaft member 2, a dynamic pressure of the lubricating oil is generated in the radial bearing gap, and the shaft portion 2a of the shaft member 2 is rotated in the radial direction by an oil film of the lubricating oil formed in the radial bearing gap. Freely supported in a non-contact manner. Thus, a first radial bearing portion R1 and a second radial bearing portion R2 that rotatably support the shaft member 2 in the radial direction in a non-contact manner are configured. At the same time, a dynamic pressure of lubricating oil is generated in the thrust bearing gap, and the flange portion 2b of the shaft member 2 is rotatably and non-contactly supported in both thrust directions by a lubricating oil film formed in the thrust bearing gap. . Thus, a first thrust bearing portion S1 and a second thrust bearing portion S2 that rotatably support the shaft member 2 in the thrust direction in a non-contact manner are configured.
[0037]
As described above, the dynamic pressure groove 8a1 of the first radial bearing portion R1 is formed so as to be asymmetric in the axial direction with respect to the axial center m, and the axial dimension X1 of the region above the axial center m is the lower region. (FIG. 3A). Therefore, when the shaft member 2 rotates, the lubricating oil drawing force (pumping force) by the dynamic pressure groove 8a1 is relatively larger in the upper region than in the lower region. The lubricating oil filled in the gap between the inner peripheral surface 8a of the bearing sleeve 8 and the outer peripheral surface 2a1 of the shaft portion 2a flows downward due to the differential pressure of the pulling force, and the lubricating oil of the first thrust bearing portion S1 The gap between the inner peripheral surface 8a of the bearing sleeve 8 and the outer peripheral surface 2a1 of the shaft portion 2a circulates through the path of the thrust bearing gap → the axial groove 8d1 → the threaded portion P → the circumferential groove 8b1 → the radial groove 8b21. And is drawn again into the radial bearing gap of the first radial bearing portion R1. In this way, by configuring the lubricating oil to flow and circulate in the internal space of the housing 7, it is possible to prevent a phenomenon in which the pressure of the lubricating oil in the internal space is locally reduced to a negative pressure. Problems such as generation of air bubbles, leakage of lubricating oil and generation of vibration due to the generation of air bubbles can be solved. Further, even if bubbles are mixed in the lubricating oil for some reason, the bubbles are discharged from the oil surface (gas-liquid interface) of the lubricating oil in the seal space S to the outside air when circulating with the lubricating oil. The adverse effects of air bubbles are more effectively prevented.
【The invention's effect】
According to the present invention, in a state where the thrust member is press-fitted, the fixing surface of the housing has a substantially straight shape in the axial direction over the entire region in the axial direction, so that the fixing surface is fixed to the inner periphery of the holding member. The fixing state is stable, and a desired fixing strength can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view of a spindle motor for information equipment using a hydrodynamic bearing device according to the present invention.
FIG. 2 is a cross-sectional view showing one embodiment of a hydrodynamic bearing device according to the present invention.
3 is a sectional view of the bearing sleeve {FIG. 3 (a)}, a lower end surface {FIG. 3 (b)}, and an upper end surface {FIG. 3 (c)}.
FIG. 4 is a view {FIG. 4 (a)} and a sectional view {FIG. 4 (b)} showing an upper end surface of the thrust member.
FIG. 5 is a partially enlarged cross-sectional view showing the periphery of a press-fit portion of a housing and the periphery of a deformation region of a fixing surface (before a thrust member is press-fitted).
FIG. 6 is a partially enlarged cross-sectional view showing the periphery of a press-fit portion of a housing and the periphery of a deformation region of a fixed surface (after press-fit of a thrust member).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Dynamic-pressure bearing device 2 Shaft member 2a Shaft part 2b Flange part 7 Housing 7b1 Press-fitting part 7d Fixed surface 7d1 Other region 7d2 Deformation region 8 Bearing sleeve 8a Inner peripheral surface 10 Thrust member R1 Radial bearing portion R2 Radial bearing portion S1 Thrust bearing portion S2 Thrust bearing

Claims (7)

A housing, a bearing sleeve fixed to an inner periphery of the housing, a shaft member having a shaft portion and a flange portion, a thrust member fixed to one end of the housing, and a portion between the bearing sleeve and the shaft portion. A radial bearing portion, which is provided and radially supports the shaft portion in a non-contact manner by a dynamic pressure action of lubricating oil generated in the radial bearing gap, and is provided between the bearing sleeve and the thrust member and the flange portion; A thrust bearing portion for supporting the flange portion in a non-contact manner in a thrust direction by a dynamic pressure action of lubricating oil generated in the dynamic pressure bearing device,
The thrust member is press-fitted with a predetermined interference into an inner periphery of a press-fit portion provided at one end of the housing,
The housing has a predetermined axial dimension on its outer periphery, and has a fixed surface that is tightly fixed to the inner periphery of the holding member,
The fixing surface has a deformation region that is deformed by a predetermined amount toward the outer diameter side in accordance with the press-fitting of the thrust member, and, in a state where the thrust member is press-fitted, is substantially straight in the axial direction over the entire axial region. The dynamic pressure bearing device according to claim 1, wherein the dynamic pressure bearing device has a simple shape. The dynamic pressure bearing device according to claim 1, wherein the deformation area of the fixed surface is adjacent to the other end of the press-fit portion of the housing. 2. The hydrodynamic bearing device according to claim 1, wherein the deformation region of the fixing surface has a tapered shape that gradually reduces in diameter toward one end of the housing before the thrust member is press-fitted. 3. . A housing, a bearing sleeve fixed to an inner periphery of the housing, a shaft member having a shaft portion and a flange portion, a thrust member fixed to one end of the housing, and a portion between the bearing sleeve and the shaft portion. A radial bearing portion, which is provided and radially supports the shaft portion in a non-contact manner by a dynamic pressure action of lubricating oil generated in the radial bearing gap, and is provided between the bearing sleeve and the thrust member and the flange portion; A method for manufacturing a hydrodynamic bearing device comprising: a thrust bearing portion for supporting the flange portion in a thrust direction in a non-contact manner by a dynamic pressure effect of lubricating oil generated in the
A press-fitting portion is formed at one end of the housing to press-fit the thrust member with a predetermined interference, and has a predetermined axial dimension on the outer periphery of the housing and is fixedly fixed to the inner periphery of the holding member. A deformation area of the fixed surface, which forms a surface and deforms by a predetermined amount toward the outer diameter side with the press-fitting of the thrust member, has an inner diameter with respect to another area of the fixed surface by an amount corresponding to the deformation amount. Back to the side,
A method of manufacturing a hydrodynamic bearing device, wherein the thrust member is press-fitted into an inner periphery of a press-fit portion of the housing and fixed. The method according to claim 4, wherein a deformation region of the fixing surface is provided adjacent to the other end of the press-fit portion of the housing. The method according to claim 5, wherein a deformation region of the fixed surface is formed in a tapered shape whose diameter gradually decreases toward one end of the housing. A motor comprising the dynamic pressure bearing device according to claim 1.

Images