JP4794964B2 - Bearing device and motor equipped with the same - Google Patents

Description

  The present invention relates to a bearing device provided with a sliding bearing.

  BACKGROUND ART A bearing device provided with a sliding bearing (hereinafter simply referred to as “bearing”) is widely used in applications that support relative rotation, sliding, or sliding rotation between a bearing and a shaft member.

As such a bearing device, for example, Patent Document 1 proposes a bearing device including a bearing component that is molded by inserting an electroformed part formed by electroforming into an axis of a resin molded part. Thus, by forming the inner peripheral surface of the bearing serving as the bearing surface by electroforming, a bearing surface having excellent wear resistance can be obtained and formed between the shaft member inserted into the inner periphery. The bearing gap can be set with high accuracy.
JP 2003-56552 A

  When the bearing device as described above is used, for example, to support a rotating shaft of a spindle motor for driving a magnetic disk of an HDD that requires high speed rotation and high rotation accuracy, lubrication between the bearing and the shaft member is improved. Therefore, oil lubrication may be necessary.

  However, the bearing gap between the inner circumferential surface of the bearing and the outer circumferential surface of the shaft member is set to a gap width as small as possible in order to suppress the shakiness of the shaft member. The amount of is very small. For this reason, if the lubricating oil is reduced due to scattering, evaporation, etc., it causes a lubrication failure due to insufficient lubricating oil, and causes problems such as generation of abnormal noise and wear of the member due to contact sliding between the bearing and the shaft member.

  An object of the present invention is to provide a bearing device having a sliding bearing with good lubrication between the bearing and the shaft member, which prevents generation of abnormal noise and wear of the member, and has a long product life.

To solve the above problems, a bearing device of the present invention is deposited formed on the outer peripheral surface of the master axis, and the electroformed part having a bearing surface on the inner periphery, electroformed part is molded by insert to the inner periphery of the resin Part, a shaft member inserted in the inner periphery of the electroformed part , a bearing gap formed between the bearing surface and the outer peripheral surface of the shaft member, and filled with lubricating oil, the bearing surface, In a bearing device comprising a straight cylindrical surface and a surface that starts to precipitate on the surface of the master shaft, an oil sump is provided adjacent to the electroformed part and capable of supplying oil to the bearing gap. Fill the oil reservoir with oil without forming an interface with the atmosphere, and provide the resin part with a portion that extends in the axial direction beyond the end of the electroformed part, and the inner peripheral surface of the part is Forming the oil sump facing the outer peripheral surface of the shaft member by molding it to a larger diameter than the outer diameter dimension And butterflies. Further, the bearing device of the present invention includes an electroformed part formed by precipitation on the outer peripheral surface of the master shaft and having a bearing surface on the inner periphery, a resin part formed by inserting the electroformed part into the inner periphery, and electroforming A shaft member inserted in the inner periphery of the part, and a bearing gap formed between the bearing surface and the outer peripheral surface of the shaft member and filled with lubricating oil, the bearing surface being a straight cylindrical surface In addition, in the bearing device having a surface that starts to precipitate on the surface of the master shaft, an oil reservoir capable of supplying oil is provided in the bearing gap, and the oil reservoir is filled with oil without forming an interface with the atmosphere. The shaft member has an outer peripheral surface adjacent to a region facing the bearing surface and provided with a small diameter portion having a smaller diameter than the region, and the oil reservoir is formed between the small diameter portion and the inner peripheral surface of the electroformed portion. It is characterized by that.

Thus, the bearing device of the present invention has an oil reservoir that supplies oil to the bearing gap. As a result, the oil retained in the oil sump is gradually supplied to the bearing gap due to the capillary phenomenon, so that the bearing device operates smoothly due to the oil film formed in the bearing gap, generating abnormal noise due to poor lubrication, Wear due to sliding contact between the shaft member and the shaft member can be avoided.

  Since the oil reservoir is in contact with the shaft member, it becomes easier to supply oil to the bearing gap, and smoother lubrication can be obtained. Such an oil reservoir can be provided, for example, between the electroformed part and the shaft member or in the resin part.

  Since the motor having the bearing device as described above operates smoothly, no abnormal noise is generated and the product life is long.

  As described above, since the bearing device of the present invention has good lubrication between the bearing and the shaft member, it is possible to prevent the generation of abnormal noise and wear of the member, and to increase the rotation speed and extend the product life.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a bearing device 1 according to a first embodiment of the present invention. The bearing device 1 supplies oil to a bearing 3, a shaft member 2 inserted in the inner periphery of the bearing 3, and a bearing gap formed between the outer peripheral surface 2 a of the shaft member 2 and the inner peripheral surface 3 a of the bearing 3. It consists of a bunkering mechanism to supply.

  The bearing 3 includes an electroformed part 4 formed by electroforming, and a resin part 5 that holds the electroformed part 4 on the inner periphery. The electroformed part 4 is formed by electroforming, and the inner peripheral surface 4a acts as a bearing surface. The resin portion 5 has a substantially cylindrical shape and is formed by molding a resin. There are no particular limitations on the form or location of the bunkering mechanism. In this embodiment, the case where the oil sump 6 is provided in the resin part 5 as an oil supplement mechanism is illustrated.

  Hereinafter, the manufacturing process of the bearing 3 will be described. The bearing 3 includes a step of masking a required portion of the master shaft 7, a step of forming an electroformed shaft 10 by electroforming a non-mask portion (see FIGS. 2 and 3), and an electroformed portion of the electroformed shaft 10. 4 is manufactured through a process of injection molding 4 with resin (see FIG. 4) and a process of separating the electroformed part 4 from the master shaft 7 and separating the bearing 3 and the master shaft 7.

  In the following description, the “rotating bearing” means a bearing that supports relative rotation with the shaft member, and it does not matter whether the bearing is on the rotating side or the fixed side. “Sliding bearing” means a bearing that supports relative linear motion with respect to the shaft, and it does not matter whether the bearing is on the moving side or the stationary side. The “rotating and sliding bearing” has both functions of the two bearings, and means a bearing that supports both rotational motion and linear motion between the shafts. Further, the “oscillating bearing” means a bearing that allows movement in the three-dimensional direction of the shaft, such as a ball joint.

  The master shaft 7 is made of a conductive material, for example, hardened stainless steel, and is manufactured as a straight shaft having a circular cross section. Of course, the material is not limited to stainless steel, but it has a mechanical function such as rigidity, slidability, heat resistance, chemical resistance, workability and separability of the electroformed part 4, and so on. A material and a heat treatment method suitable for the characteristics required above are selected. Even non-metallic materials such as ceramics can be used by conducting a conductive treatment (for example, by forming a conductive metal film on the surface). The surface of the master shaft 7 is preferably subjected to a surface treatment for reducing the frictional force with the electroformed part 4, for example, a fluorine-based resin coating.

  In addition to the solid shaft, the master shaft 7 may be a solid shaft in which a hollow shaft or a hollow portion is filled with resin. In addition, in the bearing for rotation, the cross section of the master shaft is basically formed in a circular shape, but in the case of a sliding bearing, the cross section can be made into an arbitrary shape. It can also be a perfect circle shape. In the sliding bearing, the cross-sectional shape of the master shaft 7 is basically constant in the axial direction. However, in the rotating bearing and the rotating sliding bearing, the cross-sectional shape is not constant over the entire length of the shaft. May take the form.

  Since the accuracy of the outer peripheral surface of the master shaft 7 directly affects the accuracy of the bearing gap described later, surface accuracy that is important for bearing functions such as roundness, cylindricity, and surface roughness is finished in advance with high accuracy. There is a need. For example, in a bearing for rotation, roundness is important from the viewpoint of avoiding contact with the bearing surface. Therefore, it is necessary to increase the roundness of the outer peripheral surface of the master shaft 7 as much as possible. For example, it is desirable to finish to 80% or less of an average width (radial dimension) of a bearing gap described later. Therefore, for example, when the average width of the bearing gap is set to 2 μm, it is desirable that the outer peripheral surface of the master shaft is finished to a roundness of 1.6 μm or less.

  Masking is performed on the outer peripheral surface of the master shaft 7 except for the portion where the electroformed portion 4 is to be formed (shown as dots in FIG. 2). As the masking covering 8, an existing product having non-conductivity and corrosion resistance against the electrolyte solution is selectively used.

  The electroforming is performed by immersing the master shaft 7 in an electrolyte solution containing metal ions such as Ni and Cu, and energizing the electrolyte solution to deposit the target metal on the surface of the master shaft 7. If necessary, the electrolyte solution may contain a sliding material such as carbon or a stress relaxation material such as saccharin. The type of electrodeposited metal is appropriately selected depending on the hardness, wear resistance, fatigue strength and other physical properties and chemical properties required for the bearing surface of the bearing. If the thickness of the electroformed part 4 is too thick, the peelability from the master shaft 7 is reduced, and if it is too thin, the durability of the bearing surface is reduced. The optimum thickness is set accordingly. For example, in a rotating bearing having a shaft diameter of 1 mm to 6 mm, the thickness is preferably 10 μm to 200 μm.

  By passing through the above process, the cylindrical electroformed part 4 is formed in the outer periphery of the master shaft 7, as shown in FIG. In addition, when the masking covering material 8 is thin, both ends of the electroformed portion 4 may protrude toward the covering material 8 and a tapered chamfered portion may be formed on the inner peripheral surface. Using this chamfered portion, a flange portion that prevents the electroformed portion from falling off from the resin portion can be formed. In this embodiment, the case where a chamfer part is not formed is illustrated.

  Thereafter, as shown in FIG. 3, an oil reservoir forming member 9 is disposed on the outer peripheral surface of the master shaft 7. The shape of the oil reservoir forming member 9 is not particularly limited, and may be provided at a plurality of locations separated in the circumferential direction, for example, in addition to the annular shape as shown in FIG. Further, the cross-sectional shape can be formed in an arbitrary shape such as a semicircular shape or a trapezoidal shape in addition to the rectangular shape shown in FIG.

  When the shape of the material used for the oil reservoir forming member 9 is annular as shown in FIG. 3, it can be elastically deformed so that it can be removed from the bearing 3 after separation of the bearing 3 and the master shaft 7 described later. A member is preferable, for example, formed of a rubber-based material. In the case where the shape of the oil reservoir forming member 9 is not annular, any material such as a metal or a resin can be used as long as there is no problem when it is removed from the bearing 3.

  The position where the oil sump forming member 9 is disposed is not particularly limited as long as it is within the portion where the resin portion 5 is to be formed. For example, as shown in FIG. 3, it may be disposed adjacent to the electroformed part 4, or may be disposed apart from the electroformed part 4 in the axial direction. Alternatively, the electroformed part 4 can be formed at a plurality of locations separated in the axial direction, and the oil reservoir forming member 9 can be disposed between the electroformed parts 4. Moreover, the number to arrange | position is not limited, You may arrange | position to one place like FIG. 3, and may arrange | position to multiple places.

  Thus, the electroformed shaft 10 in which the electroformed portion 4 and the oil reservoir forming member 9 are installed on the outer peripheral surface of the master shaft 7 is formed. The electroformed shaft 10 is transferred to the injection molding step shown in FIG. 4, and insert molding is performed using the electroformed portion 4, the oil reservoir forming member 9, and the master shaft 7 as insert parts.

  FIG. 4 conceptually shows an insert molding process of the resin part 5. A runner 12, a gate 13, and a cavity 14 are provided in a mold including a fixed mold 11 b and a movable mold 11 a. In this embodiment, the gate 13 is a dotted gate, and is formed at a plurality of locations (for example, at equal intervals in the circumferential direction) at positions corresponding to one axial end surface of the resin portion 5 of the molding die (fixed die 11b). Three places) formed. The gate area of each gate 13 is set to an appropriate value according to the viscosity of the molten resin to be filled and the shape of the molded product.

  In the mold having the above configuration, the movable mold 11a is brought close to the fixed mold 11b and clamped with the electroformed shaft 10 positioned at a predetermined position. Next, in a state where the mold is clamped, molten resin P is injected and filled into the cavity 14 via the spool (not shown), the runner 12, and the gate 13, and the resin portion 5 is molded integrally with the electroformed shaft 10. To do.

  The molten resin P is a thermoplastic resin, and as an amorphous resin, polysulfone (PSF), polyethersulfone (PES), polyphenylsulfone (PPSU), polyetherimide (PEI), etc., as crystalline resins, Liquid crystal polymer (LCP), polyether ether ketone (PEEK), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), or the like can be used. The type of filler to be filled in the resin is not particularly limited. For example, as the filler, fibrous filler such as glass fiber, whisker-like filler such as potassium titanate, and scaly filler such as mica. A fibrous or powdery conductive filler such as carbon fiber, carbon black, graphite, carbon nanomaterial, or metal powder can be used. These fillers may be used alone or in combination of two or more.

  After the mold opening, the molded product in which the master shaft 7, the electroformed part 4, the oil sump forming member 9, and the resin part 5 are integrated is removed from the mold. This molded product is separated into an element (see FIG. 1) composed of the electroformed part 4, the resin part 5, and the oil sump forming member 9 and the master shaft 7 in the subsequent peeling step.

  In this peeling step, the internal stress accumulated in the electroformed part 4 is released, so that the inner peripheral surface 4 a of the electroformed part 4 is expanded and peeled off from the outer peripheral surface of the master shaft 7. The internal stress is released by giving an impact to the master shaft 7 or the electroformed part 4, or applying an axial pressure between the inner peripheral surface 4 a of the electroformed part 4 and the outer peripheral surface of the master shaft 7. Is done. By releasing the internal stress, the inner peripheral surface of the electroformed part 4 is radially expanded, and a gap of an appropriate size is provided between the inner peripheral surface 4a of the electroformed part 4 and the outer peripheral surface of the master shaft 7. By forming, the master shaft 7 can be smoothly pulled out from the inner peripheral surface 4a of the electroformed part 4 in the axial direction, whereby the molded product becomes the electroformed part 4, the resin part 5, and the oil reservoir forming member 9. And the master shaft 7 are separated. The diameter expansion amount of the electroformed part 4 can be controlled, for example, by changing the thickness of the electroformed part 4, the composition of the electrolyte solution, and the electroforming conditions.

  When the diameter of the inner periphery of the electroformed part 4 cannot be sufficiently increased only by applying an impact, the electroformed part 4 and the master shaft 7 are heated or cooled, thereby causing a difference in thermal expansion between them. The electroformed part 4 can also be peeled off from the master shaft 7.

  The oil reservoir forming member 9 is removed from the elements formed of the electroformed portion 4, the resin portion 5, and the oil reservoir forming member 9 thus separated, and the bearing 3 having the oil reservoir 6 is formed.

  The volume of the oil sump 6, that is, the volume of the oil sump forming member 9, is desirably set to a ratio of 10 or more to the volume of the bearing gap in order to retain sufficient oil. Further, in the present embodiment, the case where the oil reservoir forming member 9 is formed of an elastic material such as rubber is exemplified. However, for example, the oil reservoir forming member 9 is formed of a meltable material and melted with a solvent after the separation step. It can also be formed. Alternatively, the oil reservoir 6 can be formed by forming the inner peripheral surface 3a of the bearing 3 in a cylindrical shape and removing a part of the cylindrical inner peripheral surface 3a by machining such as turning. In the present embodiment, the oil sump 6 is formed in the bearing 3, but the oil sump 6 is formed in the shaft member 2 by removing a part of the outer peripheral surface 2a of the shaft member 2 by machining such as turning. It can also be formed.

  Thereafter, a separately manufactured shaft member 2 is inserted into the bearing 3, and the bearing clearance and the oil reservoir 6 between the inner peripheral surface of the bearing 3 and the outer peripheral surface of the shaft member 2 are filled with lubricating oil. The bearing device 1 shown is completed.

  In the present embodiment, as shown in FIG. 1, the inner peripheral surface 3 a of the bearing 3 is formed by the inner peripheral surface 4 a of the electroformed part 4 and the small diameter inner peripheral surface 5 a of the resin part 5. The peripheral surface 4a acts as a bearing surface. By considering the composition of the resin material and molding conditions so that the small-diameter inner peripheral surface 5a of the resin portion 5 expands due to molding shrinkage when solidified after injection molding, a minute gap is formed between the outer peripheral surface of the master shaft 7 and the like. Can be formed. Thereby, the resin part 5 and the master shaft 7 can be easily separated. If the width of the minute gap is appropriate, in the bearing device 1 shown in FIG. 1, the minute gap between the small-diameter inner peripheral surface 5a of the resin portion 5 and the outer peripheral surface 2a of the shaft member 2 can function as a capillary seal. This is effective in preventing the lubricating oil from flowing out of the bearing gap. In addition, after the master shaft 7 is separated, the small-diameter inner peripheral surface 5a may be formed by machining or the like.

  As described above, the capillary seal expands the small-diameter inner peripheral surface 5a of the resin portion 5 and forms a small-diameter outer peripheral surface (not shown) on the outer peripheral surface 2a of the shaft member 2 that opposes the small-diameter inner peripheral surface 5a. It can also be configured. Further, if the capillary seal is a taper seal in which the gap width is gradually reduced toward the bearing gap side, it is possible to prevent the lubricating oil from flowing out more effectively.

  As the shaft member 2, the separated master shaft 7 can be used as it is. In this case, the minute gap between the inner peripheral surface 4 a of the electroformed part 4 and the outer peripheral surface of the master shaft 7 formed in the peeling process between the electroformed part 4 and the master shaft 7 functions as a bearing gap. Since this bearing gap has the characteristics that the clearance is extremely small and has high accuracy due to the characteristics of electroforming, it is possible to provide a bearing having high rotational accuracy or slidability. As described above, when a bearing is formed by replacing a separately manufactured shaft member, once the master shaft 7 is manufactured, the master shaft 7 can be reused repeatedly. Further cost reduction of the device 1 can be achieved.

  During operation (rotation, sliding, rotational sliding, or swinging) of the bearing device 1, oil supplied from the oil sump 6 is caused between the inner peripheral surface 4 a of the electroformed part 4 and the outer peripheral surface 2 a of the shaft member 2. Since an oil film is formed in the bearing gap between them, abundant lubricating oil is always present in the bearing gap. Thereby, generation of noise due to poor lubrication due to lack of oil and wear due to contact sliding between the shaft member 2 and the bearing 3 are avoided, and the product life is extended.

  The present invention is not limited to the above embodiment. In the bearing device 21 according to the second embodiment of the present invention shown in FIG. 5, the electroformed part 4 is formed on the inner peripheral surface and the inner bottom surface of the bearing 3 formed in a cup shape. A shaft member 2 having a convex spherical surface at the lower end is inserted into the inner periphery of the bearing 3. A thrust bearing portion T that supports the shaft member 2 in the thrust direction is formed between the tip of the convex spherical surface portion 2b of the shaft member 2 and the inner bottom surface 4c of the electroformed portion 4. In this case, an oil sump 6 is formed between the convex spherical surface portion 2b of the shaft member 2 and the inner peripheral surface 4a and the inner bottom surface 4c of the electroformed portion 4 as an oil supplement mechanism.

  In the bearing device 31 according to the third embodiment of the present invention shown in FIG. 6, the side portion 15 and the bottom portion 16 of the cup-shaped bearing 3 are formed separately. The bottom portion 16 is formed of, for example, a metal material, and is fixed to the side portion 15 by a method such as adhesion, high frequency welding, or ultrasonic welding. A thrust bearing portion T that supports the shaft member 2 in the thrust direction is formed between the tip of the convex spherical portion 2b of the shaft member 2 and the upper end surface 16a of the bottom portion 16 of the bearing 3. In this case, the oil enclosed in the space surrounded by the convex spherical surface portion 2b of the shaft member 2, the step portion 5b of the resin portion 5, the lower end portion of the electroformed portion 4, and the upper end surface 16a of the bottom member 16 serves as an oil supplement mechanism. It functions as a reservoir 6. In this case, since the step portion 5b of the resin portion 5 can be formed by adjusting the mold at the time of injection molding, the formation of the oil sump 6 is facilitated.

  The bearing shown above can also be used as a hydrodynamic bearing that generates pressure by the hydrodynamic action of fluid in the bearing gap between the inner peripheral surface 4a of the electroformed part 4 and the outer peripheral surface 2a of the shaft member 2. Is possible. In this dynamic pressure bearing, for example, a dynamic pressure generating part such as a dynamic pressure groove, a multi-arc surface, or a step surface formed in a herringbone shape or the like is formed on the outer peripheral surface 2a of the shaft member 2, and the dynamic pressure generating part is It can be configured by facing the perfect inner circumferential surface 4a of the electroformed part 4. On the contrary, a dynamic pressure generating part can be formed on the inner peripheral surface 4 a of the electroformed part 4. In this case, the dynamic pressure generating part of the inner peripheral surface 4 a of the electroformed part is formed on the outer peripheral surface of the master shaft 7. It can be formed by forming a mold corresponding to the shape of the dynamic pressure generating portion and performing electroforming. Thereafter, the bearing 3 and the master shaft 7 are separated in the same procedure, and the shaft member 2 having a perfect circular outer peripheral surface is inserted into the inner periphery of the bearing 3 to constitute a hydrodynamic bearing.

  The bearing device described above can be used by being incorporated in a motor for information equipment, for example. Hereinafter, the example which used the bearing apparatus 1 as a rotating shaft support apparatus for the said motor is demonstrated based on FIG.

  As shown in FIG. 7, the motor 100 is used as a spindle motor for a disk drive device such as an HDD, and includes a bearing device 1 that rotatably supports a shaft member 2 in a non-contact manner, and a shaft member. 2, and a stator coil 104 and a rotor magnet 105 that are opposed to each other with a gap in the radial direction, for example. The stator coil 104 is attached to the outer periphery of the bracket 106, and the rotor magnet 105 is attached to the inner periphery of the disk hub 103. The disk hub 103 holds one or more disks D such as magnetic disks. When the stator coil 104 is energized, the rotor magnet 105 is rotated by the electromagnetic force between the stator coil 104 and the rotor magnet 105, whereby the disk hub 103 and the disk D held by the disk hub 103 are integrated with the shaft member 2. Rotate to.

  In this embodiment, the bearing device 1 includes a bearing 3, a shaft member 2 inserted into the inner periphery of the bearing 3, and a thrust plate 107 attached to one end of the bearing 3. Although FIG. 7 illustrates the bearing device 1 shown in FIG. 1 as the bearing device, the bearing devices 21 and 31 shown in FIGS. 5 and 6 can also be used. On the upper end surface of the thrust plate 107, a region (thrust bearing surface) 107a in which a plurality of dynamic pressure grooves are arranged in a spiral shape is formed as a thrust dynamic pressure generating portion. When the shaft member 2 is rotated, an oil film is formed in a radial bearing gap between the outer peripheral surface 2a of the shaft member 2 and the inner peripheral surface 4a of the electroformed portion 4 serving as the radial bearing surface of the bearing 3, and thereby the shaft member 2 is radially A radial bearing portion R that is supported in a non-contact manner so as to be rotatable in the direction is formed. At the same time, in the thrust bearing gap between the lower end surface 2c of the shaft member 2 and the upper end surface 107a of the thrust plate 107, the shaft member 2 is supported in a non-contact manner so as to be rotatable in the thrust direction by the dynamic pressure action of lubricating oil by the dynamic pressure grooves A thrust bearing portion T is formed.

  The bearing device of the present invention is not limited to the above examples, and is used in a small motor for information equipment used under high-speed rotation, a polygon scanner motor of a laser beam printer, etc. It can also be suitably used for rotating shaft support. It can also be applied to fan motors that require a long service life.

  In the above description, the case where the bearing 3 is used for supporting the rotating shaft is illustrated, but in addition to this, the bearing 3 is a sliding bearing that supports linear relative sliding with respect to the shaft. The present invention can be applied to either a sliding rotation bearing that supports both relative sliding and relative rotation, or a rocking bearing that supports the movement of the shaft in the three-dimensional direction.

1 is a cross-sectional view of a bearing device 1 according to a first embodiment of the present invention. It is a perspective view which shows the state which formed the electroformed part 4 in the master axis | shaft 7. FIG. 1 is a perspective view of an electroformed shaft 10. FIG. It is sectional drawing which shows the state which attached the electroformed shaft 10 to the injection mold. It is sectional drawing of the bearing apparatus 21 which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the bearing apparatus 31 which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows schematic structure of the motor 100 to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bearing apparatus 2 Shaft member 3 Bearing 4 Electroformed part 5 Resin part 7 Master shaft 8 Cover material 9 Oil reservoir forming member 10 Electroformed shaft 100 Motor R Radial bearing part T Thrust bearing part

Claims (3)

Is deposited formed on the outer peripheral surface of the master axis, the inner and electroformed part having a bearing surface in a circumferential, a resin portion molded by insert to the inner peripheral of the electroformed part, the shaft inserted into the inner circumference of the electroformed part And a bearing gap formed between the bearing surface and the outer peripheral surface of the shaft member and filled with lubricating oil. The bearing surface is a straight cylindrical surface and is deposited on the surface of the master shaft. In the bearing device consisting of the surface that started
Arranged adjacent to the electroformed part, providing an oil reservoir capable of supplying oil to the bearing gap, and filling the oil reservoir without forming an interface with the atmosphere;
The resin part is provided with a part extending in the axial direction beyond the end of the electroformed part, and the outer peripheral surface of the shaft member is formed by forming the inner peripheral surface of the part larger than the outer diameter of the electroformed part. A bearing device characterized in that the oil reservoir facing the surface is formed . An electroformed part deposited on the outer peripheral surface of the master shaft and having a bearing surface on the inner periphery, a resin part formed by inserting the electroformed part into the inner periphery, and a shaft inserted into the inner periphery of the electroformed part And a bearing gap formed between the bearing surface and the outer peripheral surface of the shaft member and filled with lubricating oil. The bearing surface is a straight cylindrical surface and is deposited on the surface of the master shaft. In the bearing device consisting of the surface that started
  An oil reservoir capable of supplying oil to the bearing gap is provided, and the oil reservoir is filled with oil without forming an interface with the atmosphere.
  An outer peripheral surface of the shaft member is adjacent to a region facing the bearing surface, and a small diameter portion having a smaller diameter than the region is provided, and the oil reservoir is formed between the small diameter portion and the inner peripheral surface of the electroformed portion. A bearing device characterized by that. A motor comprising the bearing device according to claim 1 .

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