JP2002300761A - Motor and disk drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor which prevents leakage of oil for bearing, prevents its rotor shaft from coming off the stator side, withstands a large impact from outside and a disk drive device. SOLUTION: A rotor 14 has a turn table 30 mounting a disk D, a shaft 20 fixed to the turn table 30 and a shaft coming-off preventing member 100 fixed to the shaft 20 halfway. A stator 16 has a bearing 70 rotatably supporting the shaft 20 of the rotor 14, a bearing holder 60 fixing the bearing 70 inside having an opening 112 on one end 110 and closing another end 114, and a rotor stopper 120 having a hole to pass the shaft 20, closing the opening 112 of the bearing holder 60 by being fixed to the end 110 of the bearing holder 60, and preventing the shaft 20 from coming off the bearing holder 60 by hitting the coming-off preventing member 100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor and a disk drive for rotating a mounted object such as a disk-shaped information recording medium.

[0002]

2. Description of the Related Art FIG. 18 shows a disk drive device for rotating a disk D. The turntable 1000 of the disk drive device is a portion where the disk D is removably mounted. The turntable 1000 of the rotor 1001 is integrated with the rotor yoke 1002, and a driving magnet 1003 is fixed in the rotor yoke 1002. The stator 1004 rotatably supports the shaft 1005 of the rotor 1001. The stator 1004 has a housing 1006, a thrust plate 1007, a bearing 1008, and the like. Housing 1006 is fixed to stator wiring board 1009. The housing 1006 has a coil 101
0 and the like are fixed. By energizing the coil 1010 from the outside in a predetermined energizing pattern, the coil 1
010 and the driving magnet 1003
Magnetic field interact magnetically, the rotor 1001
Rotate continuously with respect to the stator 1004 about the shaft 1005.

[0003] One end of the bearing holder 1006 has an opening 1014. This opening 1014 faces the disk D and the turntable 1000 side.
The bearing holder 1006 is connected to the housing hook portion 102.
0, and the turntable 1000 has a stopper spring 1030. The stopper spring 1030 meshes with the housing hook portion 1020 to prevent the rotor 1001 from coming out of the stator 1004 along the shaft 1005. The information stored in the disk D is irradiated with light from the optical pickup 1040, and the light is reflected by the disk D to
By returning to 0, it can be read.

[0004]

However, such a conventional disk drive has the following problems. Since the opening 1014 of the bearing holder 1006 is formed so as to face the disk D and the turntable 1000, the oil contained in the bearing 1008 and the oil in the bearing holder 1006 pass from the opening 1014 to the disk D and the turntable 1000. Will leak. In particular, when the disc D and the turntable 1000 are used in a downward position, which is located on the lower side, the opening 101
4 faces downward, the oil easily leaks from the opening 1014 to the disk D and the turntable 1000 side by its own weight.

In a conventional structure in which the rotor 1001 is prevented from coming off by the housing hook portion 1020 and the stopper spring 1030, for example, the shaft
When an impact of 0 G or more is applied, it is physically difficult to secure mechanical strength so that the rotor 1001 does not slip out of the stator 1004. That is, one stopper spring 1030 is provided, and the turntable 1
Since it is not provided over the entire circumference of 000,
Even if the stopper spring 1030 is hooked on the housing hook portion 1020, it cannot withstand a large shock of 600 G or more. Therefore, the present invention solves the above problems, prevents the oil for bearings from leaking, prevents the shaft of the rotor from slipping out of the stator side, and can withstand a greater external impact. It is intended to provide.

[0006]

According to a first aspect of the present invention, there is provided a motor having a stator and a rotor which rotates with respect to the stator when energized. A shaft fixed to the mounting portion, and a shaft retaining member fixed in the middle of the shaft, wherein the stator rotatably supports the shaft of the rotor, and the bearing A bearing holder having an opening at one end and a closed end at the other end, and a hole through which the shaft passes, and is fixed to the one end of the bearing holder, and A rotor stopper that closes the opening and prevents the shaft from coming out of the bearing holder when the stopper member of the shaft of the rotor comes into contact with the rotor stopper.

According to the first aspect, the mounting portion of the rotor mounts an object to be mounted. The shaft is fixed to the mounting part. The shaft retaining member is fixed in the middle of the shaft. The bearing of the stator rotatably supports the shaft of the rotor. The bearing holder has the bearing fixed inside, and has an opening at one end and a closed other end. The rotor stopper has a hole through which the shaft passes, and is fixed to one end of the bearing holder to close the opening of the bearing holder. The shaft stopper is prevented from falling out of the bearing holder by contacting the rotor stopper with a stopper member of the shaft of the rotor. Since the rotor stopper closes the opening of the bearing holder,
Oil in the bearing holder is prevented as much as possible from the outside. Moreover, the stopper member of the shaft abuts against the rotor stopper, thereby completely preventing the shaft of the rotor from coming out of the bearing holder of the stator even when a large external impact is applied.

According to a second aspect of the present invention, in the motor according to the first aspect, an inner peripheral surface of the rotor stopper forming the hole through which the shaft passes and an outer peripheral surface of the shaft corresponding to the inner peripheral surface are formed. The portion is provided with an oil leakage prevention coating that prevents oil in the bearing holder from leaking from between the inner peripheral surface of the rotor stopper and the outer peripheral surface of the shaft. According to the second aspect, an oil leakage prevention coating is applied to the inner peripheral surface of the rotor stopper and the outer peripheral surface of the shaft.
Oil can be prevented from leaking from a gap between the outer peripheral surface of the shaft and the inner peripheral surface of the rotor stopper as much as possible.

According to a third aspect of the present invention, in the motor according to the first aspect, the oil leakage prevention coating is the resin coating.

According to a fourth aspect of the present invention, in the motor according to the first aspect, the rotor stopper has an air vent hole for connecting the inside of the bearing holder and the outside of the bearing holder. According to the fourth aspect, since the rotor stopper has the air vent hole, the rotor stopper can be easily fixed to one end of the bearing holder without air resistance.

According to a fifth aspect of the present invention, in the motor according to the first aspect, the rotor stopper and the shaft retaining member have a ring shape. According to the fifth aspect, the rotor stopper and the stopper member for the shaft are both ring-shaped, and the rotor stopper and the stopper member can prevent the shaft from coming off over the entire circumference of the shaft. Withstands shock, for example, about 1000 G shock.

According to a sixth aspect of the present invention, in the motor according to the second aspect, the rotor stopper is a ring-shaped mounting member fixed to the one end of the bearing holder, and the rotor stopper is fixed to the mounting member. A ring-shaped attachment member that forms the hole through which a shaft passes. The oil leakage prevention coating is applied to the inner peripheral surface of the ring-shaped attachment member.

According to a seventh aspect of the present invention, there is provided a disk drive device including a stator and a motor having a rotor that rotates with respect to the stator when energized, and rotating a disk-shaped information recording medium with the rotor. The rotor of the motor has a mounting portion for mounting the disc-shaped information recording medium, a shaft fixed to the mounting portion, and a shaft retaining member fixed in the middle of the shaft,
The stator of the motor has a bearing rotatably supporting the shaft of the rotor, a bearing holder that fixes the bearing inside, and has an opening at one end and a closed other end, It has a hole through which a shaft passes, and is fixed to the one end of the bearing holder, closes the opening of the bearing holder, and the shaft comes out of the bearing holder by being hit by the retaining member of the shaft of the rotor. And a rotor stopper for preventing the disk drive from slipping out. According to claim 7, the mounting portion of the rotor mounts an object to be mounted. The shaft is fixed to the mounting part. The shaft retaining member is fixed in the middle of the shaft. The bearing of the stator rotatably supports the shaft of the rotor. The bearing holder has the bearing fixed inside, and has an opening at one end and a closed other end. The rotor stopper has a hole through which the shaft passes, and is fixed to one end of the bearing holder to close the opening of the bearing holder. The shaft stopper is prevented from falling out of the bearing holder by contacting the rotor stopper with a stopper member of the shaft of the rotor. Since the rotor stopper closes the opening of the bearing holder, the oil in the bearing holder is prevented as much as possible from outside. Moreover, the stopper member of the shaft abuts against the rotor stopper, thereby completely preventing the shaft of the rotor from coming out of the bearing holder of the stator even when a large external impact is applied.

According to an eighth aspect of the present invention, in the disk drive device according to the seventh aspect, an inner peripheral surface of the rotor stopper forming the hole through which the shaft passes, and an outer peripheral surface of the shaft corresponding to the inner peripheral surface. The surface portion is provided with an oil leakage prevention coating that prevents oil in the bearing holder from leaking from between the inner peripheral surface of the rotor stopper and the outer peripheral surface of the shaft. According to the present invention, since the oil leakage prevention coating is applied to the inner peripheral surface of the rotor stopper and the outer peripheral surface of the shaft, oil flows from a gap between the outer peripheral surface of the shaft and the inner peripheral surface of the rotor stopper. Leakage can be prevented as much as possible.

According to a ninth aspect of the present invention, in the disk drive device according to the seventh aspect, the oil leakage prevention coating is the resin coating.

According to a tenth aspect of the present invention, in the disk drive device according to the seventh aspect, the rotor stopper comprises:
There is an air vent hole connecting the inside of the bearing holder and the outside of the bearing holder. In claim 10,
Since the rotor stopper has an air vent hole, the rotor stopper can be easily fixed to one end of the bearing holder without air resistance.

According to an eleventh aspect of the present invention, in the disk drive device according to the seventh aspect, the rotor stopper and the shaft retaining member are ring-shaped. According to the eleventh aspect, the rotor stopper and the stopper member for the shaft are both ring-shaped, and the rotor stopper and the stopper member can prevent the shaft from coming off over the entire circumference of the shaft. Withstands shock, for example, about 1000 G shock.

According to a twelfth aspect of the present invention, in the disk drive device according to the eighth aspect, the rotor stopper comprises:
A ring-shaped attachment member fixed to the one end of the bearing holder, and a ring-shaped attachment member fixed to the attachment member and forming the hole through which the shaft passes; Is coated with the oil leakage preventing coating.

[0019]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the embodiments described below are preferred specific examples of the present invention,
Although various technically preferable limits are given, the scope of the present invention is not limited to these modes unless otherwise specified in the following description.

Embodiment 1 FIGS. 1 and 2 show an example of a disk drive device having a motor according to the present invention. The disk drive device 1 shown in FIG. 1 has a motor 10 and an optical pickup 12. The motor 10 has a rotor 14 and a stator 16. The rotor 14 includes a shaft 20, a rotor yoke 22,
It has a main magnet 24 for driving and a turntable 30. The turntable 30 is made of, for example, brass, and is a mounting portion that detachably holds the disk D by a chucking member (not shown). For example, the magnetic force generated between the magnet of the chucking member and the yoke 30A of the turntable 30 allows the disk D to be detachably mounted on and held on the turntable 30. Alternatively, a magnet for holding is disposed on the turntable 30 in place of the yoke 30A, and the magnet magnetically attracts a chucking member of the disk D to detachably mount the disk D on the turntable 30. It can also be mounted and held. In this manner, the turntable 30 mounts the disk D, which is the object to be mounted.

The disk D is a disk-shaped information recording medium such as a DVD (digital versatile disk),
CD (compact disk, optical disk), CD-RO
Other types of disks such as M (read only memory using a compact disk), MD (mini disk) which is a kind of magneto-optical disk, and a magnetic disk such as a hard disk may of course be used. The optical pickup 12 has, for example, a function of optically reading information stored in the disk D, and irradiates the disk D with light P such as laser light to The information of D can be read optically. However, the optical pickup 12 may have a recording / reproducing function of not only reading such information but also writing information on the disk D.

1 is made of, for example, stainless steel (eg, SUS420).
A turntable 30 is fixed to the upper end portion of the, for example, by press-fitting. The rotor yoke 22 of the rotor 14 is also called a rotor case, and is made of, for example, an iron plate. The rotor yoke 22 is fixed to the turntable 30 by, for example, caulking. The main driving magnet 24 is ring-shaped, and has N poles and S poles alternately and multipolarly magnetized along the circumferential direction, and is bonded to the inner peripheral surface of the rotor yoke 22 by, for example, bonding. Fixed. The magnet 24 is made of, for example, a neodymium sintered material.

Next, the stator 16 of FIG. 1 will be described. The stator 16 includes a stator wiring board 40,
It has an iron core 42, a coil 44, a housing 50, a bearing holder 60, and a bearing 70. By energizing the coil 44 from outside through a stator wiring board 40 also called a base in a predetermined energizing pattern, the coil 4
4 interacts with the magnetic field of the magnet 24 of the rotor 14 so that the rotor 14
Rotate against.

The stator wiring board 40 is an example of a support plate (base) for supporting the housing 50, and may be a metal or a normal printed board. The housing 50, also called the main housing, is made of metal,
For example, it is made of stainless steel. The cylindrical bearing holder 60 is made of metal, for example, stainless steel. As the cylindrical bearing 70, any of a metal bearing and a plastic bearing can be adopted. The iron core 42 and the coil 44 are fixed to the outer peripheral portion of the bearing holder 60.

A cylindrical bearing 70 is housed and fixed on the inner peripheral surface of the bearing holder 60. The cylindrical bearing 70 is fixed in the bearing holder 60 by, for example, press fitting. A thrust receiver 51 is disposed on the inner bottom surface of the housing 50, and rotatably supports the lower end of the shaft 20. As a result, the shaft 20 is
And the thrust receiver 51 can rotate about the central axis CL.

FIGS. 3 and 4 show the structure of the stator 16 and the structure of the shaft 20 of the rotor 14 shown in FIG. The housing 50 is fixed to the stator wiring board 40 by, for example, caulking. Another cylindrical portion 50B is fixed to cylindrical portion 50A of housing 50 by, for example, press fitting. A bearing 70 is press-fitted and fastened to the inner peripheral surfaces of the cylindrical portions 50A and 50B. Bearing 70
Is a metal bearing or a plastic bearing,
So-called oil-impregnated bearings or other types can be employed. The bearing 70 may or may not be a dynamic pressure bearing having a herringbone groove or the like. The inner peripheral surface of the bearing 70 is subjected to sizing processing and then press-fitted to the inner peripheral surfaces of the cylindrical portions 50A and 50B for fastening. The cylindrical parts 50A and 50B are the bearing holder 6
0. In the middle of the shaft 20, a shaft retaining member 100 is fixed by press-fitting. The shaft retaining member 100 has a ring shape and is made of, for example, stainless steel. The clearance between the outer peripheral surface of the retaining member 100 and the inner peripheral surface of the cylindrical portion 50B is, for example, 5 μm.
m.

The bearing holder 60 shown in FIGS. 3 and 4 is composed of the cylindrical portions 50B and 50A as described above.
One end 110 of the bearing holder 60 has an opening 112
Is provided. The other end 114 of the bearing holder 60
Is closed, and the thrust receiver 51 is disposed. The thrust receiver 51 rotatably supports one end of the shaft 20. A rotor stopper 120 is fixed to one end 110 of the housing 50 in FIG. As shown in FIGS. 3 and 4, the rotor stopper 120 has a ring-shaped mounting member 130 and a ring-shaped attached member 140. The mounting member 130 is also called a washer cover or the like, and is made of, for example, brass. The attachment member 140 is also called an oil washer or the like, and can be made of a resin having an oil-repelling property, for example, PTEF (polytetrafluoroethylene).

As shown in FIG. 4, the mounting member 130 is
It has a hole 144 for passing 0 through. This hole 144
Has hole portions 145, 146, and 147. The inner diameter of the hole 147 is set to be larger than the outer diameter of the shaft 20 with a predetermined clearance. The inner diameter of the hole 145 is larger than the inner diameter of the hole 147, and the inner diameter of the hole 146 is even larger than the inner diameter of the hole 145. In the hole portion 145, the attachment member 140 is fitted and arranged. An adhesive 149 is disposed between the attachment member 140 and the attachment member 130 and in the hole portion 146. Thereby, the attachment member 140 is attached to the attachment member 13.
0 can be reliably fixed.

The clearance between the inner diameter of the hole portion 147 and the outer diameter of the shaft 20 is desirably, for example, 50 μm or less. The clearance between the inner diameter of the attachment member 140 and the outer diameter of the shaft 20 is desirably, for example, 50 μm or less. These clearance values are more preferably 10
It is not less than μm and not more than 50 μm. If the clearance is smaller than 10 μm, component tolerances will accumulate, making it difficult to obtain a sufficient clearance and increasing the cost. Moreover, the maximum clearance between the shaft and the bearing is 7-8μ.
m, there is a possibility of physically hitting when starting the motor. On the other hand, if the clearance exceeds 50 μm, the oil sealing effect is unfavorably reduced. This range of numerical values can be applied to other embodiments.

The inner diameter of the hole portion 147 of the hole 144 is set smaller than the outer diameter of the shaft retaining member 100.
Thus, when the shaft 20 in FIG. 3 tries to come off in the E1 direction, the shaft retaining member 100 comes into contact with the contact surface 150 of the mounting member 130. Therefore the shaft 20
Can be completely prevented from falling out of the cylindrical portions 50A and 50B of the bearing holder 60 of the housing 50 of the stator 16. Further, by using the attachment member 130 and the attachment member 140 of the rotor stopper 120, it is possible to reliably prevent the bearing oil contained in the bearing holder 60 from leaking. That is, as described above, the clearance between the inner diameter of the hole portion 147 and the outer diameter of the shaft 20 and the clearance between the inner diameter of the accessory member 140 and the outer diameter of the shaft 20 are set to the predetermined values as described above. Because.
The material of the adhesive is, for example, TB13 manufactured by Three Bond Co., Ltd.
An appropriate amount of 59D adhesive is applied and cured by irradiation with ultraviolet light.

The attachment member 140, also called an oil washer, has a mounting jig 15 as shown in FIG.
2 is used to mount in the hole 145 of the mounting member 130 shown in FIGS. Then, as shown in FIG. 5B, the above-mentioned clearance is set between the outer peripheral surface of the shaft 20 and the inner peripheral surface of the accessory member 140 by using another mounting jig 151. When the attached member 140 is made of, for example, PTEF, an oil barrier liquid is applied to the outer peripheral surface of the shaft 20 facing the inner peripheral surface of the attached member 140. This oil barrier liquid is a kind of oil leakage prevention coating.

By adopting the structure of FIGS. 1 to 5,
For example, due to the action of the accessory member 140 formed of PTEF, which is a type of Teflon material, and the oil barrier liquid formed on the corresponding outer peripheral surface of the shaft 20, the contact angle between the oil rising along the shaft 20 and the oil increases. For example, by maintaining the temperature at about 70.8 degrees, compared to using a general metal member, there is an oil-producing agent effect, and oil leakage to the outside of the bearing holder 60 can be reliably prevented.

The retaining member 1 of the shaft shown in FIGS.
Since the structure is such that 00 abuts against the contact surface 150 of the mounting member 130 of the rotor stopper 120, it is possible to reliably prevent the rotor shaft 20 from falling out of the bearing holder 60. In addition, since the retaining member 100 of the shaft has a ring shape along the shaft 20 and the mounting member 130 has a ring shape, it can withstand an externally applied impact along the entire circumferential direction of the shaft 20, When the retaining member 100 abuts against the contact surface 150, it can withstand a large external impact, for example, an impact of about 1000G. For this reason, especially in the bearing structure of the illustrated motor 10 such as a thin spindle motor, the bearing can be made thinner and mechanical reliability can be ensured, and the clearance between the shaft and the attached member 140 can be optimized. By setting, it is possible to prevent the oil of the bearing from leaking from the opening 112 of the bearing holder 60 shown in FIG. 4 as much as possible. The clearance between the shaft and the attached member as a seal can be mechanically controlled, and the reliability of the bearing can be improved.

Second Embodiment FIGS. 6 to 8 show a second embodiment of the disk drive device of the present invention. The same reference numerals are given to the portions of the disk drive device 1 of FIG. 6 corresponding to the disk drive device 1 of FIG. 1, and the description thereof will be used. 6 is replaced with the disk drive 1 of FIG.
6 and 8 are different from each other in the shape of the rotor stopper 220 and the like.

As shown in FIG.
Are a ring-shaped mounting member 230 and a ring-shaped attached member 2
40. The ring-shaped attachment member 240 is also called an oil washer or the like. On the inner peripheral surface of the attached member 240, a resin coating, for example, a Teflon coating 241 which is a kind of oil leakage prevention coating, is formed. Similarly, in the middle of the outer peripheral surface of the shaft 20,
Again, a Teflon coating 242 is formed.
The thickness of the Teflon coatings 241 and 242 is, for example, 10 to 20 μm. In the middle of this axis 20,
In the vicinity of the Teflon coating 242, a shaft retaining member 100 is fixed by press fitting or the like. As shown in FIG. 8 (B), the shaft retaining member 100 fits into the hole 250 of the mounting member 230.
The shaft 20 can be prevented from coming off in the E1 direction by the contact surface 250A of the shaft retaining member 100 and the hole 250 of the mounting member 230. The mounting member 230 is fixed to the one end 110 of the bearing holder 60. The attachment member 240 is fixed to the hole 251 of the attachment member 230 using an adhesive 252. Alternatively, the ring-shaped attachment member 240 can be fixed to the hole portion 251 by press fitting.

As shown in FIG. 8, in the hole 250 of the mounting member 230, an angle θ is set to a contact surface 250A which is an inner diameter thereof. Contact surface 25 having this angle θ
0A is also referred to as a tapered portion.
0 degrees. By providing the tapered portion 260 on the opening 112 side of the bearing holder 60 in this manner, the shaft 20
The structure can also have a centrifugal force effect of the rotation of. That is, when the shaft 20 rotates, the rotational force of the oil in the bearing 70 (F = mrω ² sin θ) is obtained, and the oil in the bearing holder 60 moves in the direction E in FIG. 8A. This has the effect of preventing oil from leaking between the outer peripheral surface of the shaft 20 and the inner peripheral surface of the attachment member 240. Further, by providing such a tapered portion 260, the oil moves automatically so that oil is supplied between the bearing 70 and the outer peripheral surface of the shaft 20, so that the inner peripheral surface of the bearing 70 and the shaft The oil can be supplied between the outer peripheral surfaces of the first and second motors 20.

The distance a from the attachment member 240 shown in FIG. 8B to the lower surface of the shaft retaining member 100 is different from the surface of the attachment member 140 in the first embodiment shown in FIG. It can be smaller than the distance b to the lower surface.

FIG. 9 shows an example of a state in which the Teflon coating 241 on the inner peripheral surface of the attachment member 240 and the Teflon coating 242 on the shaft 20 prevent the oil 299 of the bearing from leaking in the case of FIG. 8, for example. I have.
Oil 299 has Teflon coating 241, 242
Is kept at, for example, about 110 ° or more, it is possible to reliably prevent the oil 299 from leaking along the E1 direction.

As a countermeasure against oil leakage from the opening, there is a method of providing a predetermined surface tension sealing effect between the wall surface facing the shaft and a countermeasure. In order to increase the oil sealing force, a Teflon material is added to the oil washer facing the shaft to increase the contact angle θ1, and to further reduce the gap to increase the sealing effect, the attached member 240 is fixed to the mounting member 230 with respect to the mounting member 230. A predetermined clearance is provided between the inner surface of the attached member 240 and the outer surface of the shaft 20 by the jig. Assuming that the energy due to the capillary action is a standard and the height is h, T: the surface tension of the liquid, θ1: the contact angle between the pipe and the liquid surface, r: the radius of the pipe, ρ: the density of the liquid, and G: 980, the height h = 2T cos θ1 / r ρ g.
The smaller r (the narrower the gap), the greater the capillary action. When the contact angle θ is large, the effect of moistening the liquid is weakened, and when θ1> 90 °, the liquid is not moistened. In one example of the oil used in the embodiment of the present invention, the contact angle θ1 with the metal is 2
It is 3.45 °, but about 110 ° for Teflon material.
In order to promote the effect of increasing the contact angle θ to prevent moistening, a 110 degree contact degree of the coated Teflon material is used. This difference can be expected to be effective as an oil barrier material that repels oil.

In the first and second embodiments, a predetermined rotor stopper is attached to a dedicated bearing holder.
This rotor stopper serves both as a countermeasure against oil leakage and an effect of removing the shaft. As a result, a structure in which measures against oil leakage in the bearing are stabilized can be obtained. By providing Teflon seals on the inner periphery of the rotor stopper and the outer periphery of the shaft, the shaft
It is possible to provide a bearing structure that has an oil barrier effect between seals and also has a structure of a surface tension sealing effect with high confidentiality. Generally, a fluorine-based liquid (3M Fullerode, etc.) is used as the oil barrier liquid, but since it is a liquid, there are some difficulties in the application work. However, the solid composition such as Teflon material can increase the degree of contact and improve reliability. The performance is further improved. The end surface of the accessory member, which is a washer, is provided with an inclination of about 30 degrees as illustrated in FIG. 8 so as to have a structure that also has a centrifugal effect of shaft rotation. mrω ² si
nθ) is obtained, and the oil is moved downward, which has the effect of preventing leakage force between the shaft and the oil washer. Further, the oil is automatically moved between the bearing gaps and supplied.

Third Embodiment FIGS. 10 to 13 show a third embodiment of the present invention. The same reference numerals are given to the portions of the disk drive device 1 of FIG. 10 corresponding to those of the disk drive device 1 of FIG. 1, and the description thereof will be used. The difference between the disk drive device 1 of FIG. 10 and the disk drive device of FIG.
This is the structure of the rotor stopper 320. As shown in FIGS. 12 and 13, the rotor stopper 320 is formed of one member and has hole portions 321, 322, and 323. The inner diameter of the hole 321 is larger than the inner diameter of the hole 322, and the inner diameter of the hole 322 is larger than the inner diameter of the hole 323. A Teflon coating 340 is formed on the inner peripheral surface of the hole 323 of the ring-shaped rotor stopper 320. Another Teflon coating 341 is formed on the outer peripheral surface in the middle of the shaft 20. The thickness of the Teflon coatings 340 and 341 is, for example, 10 to 2
0 μm. In the middle of the shaft 20 and in the vicinity of the Teflon coating 341, a shaft retaining member 100 is fixed by press-fitting or bonding as shown in FIG. 13. The rotor stopper 320 is fixed to the opening 112 side of the one end 110 of the bearing holder by press-fitting or bonding.

The air vent hole 380 is provided in the rotor stopper 3
It is formed so as to communicate with the holes 322 and 321 from the outer peripheral surface of the shaft 20 and is parallel to the axial direction of the shaft 20. By providing the air vent hole 380 for the rotor stopper 320, the rotor stopper 320 can be easily inserted and fixed to the one end 110 of the bearing holder 60. That is, the one end 110 of the bearing holder 60 is released, but the other end 114 is closed. Therefore, since such an air vent hole 380 is formed in the rotor stopper 320, there is no air resistance. The rotor stopper 320 can be easily fixed to the one end 110. The air vent hole 380 is closed by, for example, packing a ball or a rod into the air vent hole 380 after the air vent hole 380 is attached and the air is evacuated from the air vent hole 380. This prevents the oil in the bearing holder from escaping from the air vent hole 380.

Since the Teflon coating 340 of the rotor stopper 320 and the Teflon coating 341 on the shaft 20 side are formed, the contact angle between the Teflon coating 340, 341 and the oil is maintained at, for example, about 110 ° as described above. Therefore, it is possible to prevent oil from leaking to the outside. Since the shaft retaining member 100 comes into contact with the contact surface 377 of the rotor stopper 320, it is possible to prevent the rotor shaft 20 from coming off in the E1 direction. As described above, the clearance between the Teflon coating 340 and the Teflon coating 341 is preferably, for example, 10 μm to 50 μm, and particularly preferably 10 μm to 20 μm.

In the bearing structure for a thin spindle motor according to the embodiment of the present invention, a predetermined oil seal material and a bearing structure are formed to make the bearing thin and secure mechanical reliability, and the bearing is in contact with the clearance between the shaft and the seal. By applying a resin coating having a high angle and providing an oil air vent hole in a predetermined portion of the rotor stopper, the air in the oil can be reliably vented and held. As a result, it is possible to prevent oil in the bearing from leaking out of the bearing holder.

A rotor stopper is attached to a dedicated bearing holder, and an air vent hole having a diameter of, for example, 0.3 mm is provided at a predetermined position of the rotor stopper, thereby facilitating press fitting of the rotor stopper to the bearing holder. Can be. Further, the air accumulated in the bearing oil can be easily removed, and the reliability of the assembly of the bearing holder and the bearing can be maintained. As a result, it is possible to adopt a configuration that has both an oil leakage countermeasure and a shaft detachment effect.

By providing a seal made of Teflon material on the inner periphery and the outer periphery of the rotor stopper, an oil barrier effect is provided between the shaft and the seal, and at the same time, a bearing structure having a surface tension sealing effect with high confidentiality is provided. Is possible. Generally, a fluorine-based liquid (3M fullerode, etc.) is used as the oil barrier liquid. However, since the liquid is liquid, there are some difficulties in applying the liquid. However, the solid composition such as Teflon improves reliability.

Fourth Embodiment FIGS. 14 to 16 show a fourth embodiment of the present invention. The same reference numerals are given to portions of the disk drive device 1 of FIG. 14 corresponding to those of the disk drive device of FIG. 14 differs from the disk drive device of FIG. 1 in the structure of the rotor stopper 420. Rotor stopper 42
0 has a ring-shaped attachment member 510 and a ring-shaped attachment member 520 as shown in FIGS. 16 (A) and 16 (B). The ring-shaped mounting member 510 has a substantially U-shaped cross section to close the opening of the one end 110 of the bearing holder 60. The ring-shaped mounting member 510 has a hole 511 through which the shaft 20 passes. A predetermined clearance is formed between the inner peripheral surface 521 of the ring-shaped attachment member 520 and the outer peripheral surface of the shaft 20. The shaft retaining member 100 is fixed in the middle of the shaft 20 by press-fitting or bonding. A predetermined clearance is formed between the outer peripheral surface of the shaft retaining member 100 and the inner peripheral surface of the cylindrical portion 50B of the bearing holder 60. The clearance between the shaft retaining member 100 and the inner peripheral surface of the cylindrical portion 50B is set in any of the above-described embodiments.

The ring-shaped attachment member 5 shown in FIG.
Of course, an oil leakage prevention coating such as a Teflon coating may be formed on the inner peripheral surface 521 of the shaft 20, and a Teflon coating may also be formed on the corresponding outer peripheral surface of the shaft 20. The ring-shaped mounting member 510 is fixed by bonding or press-fitting so as to cover the one end 110 of the bearing holder 60.

FIG. 17 shows a modification of the bearing holder and the rotor stopper of the embodiment shown in FIGS. The rotor stopper 320A in this example has an air vent hole 380A and hole portions 323A and 321A. The outer diameter of the rotor stopper 320A is shown in FIGS.
Unlike the example of FIG. 3, the outer diameter of the portion 50B of the bearing holder 60 is the same.

The present invention is not limited to the above embodiment. The Teflon coating, which is an example of the resin coating, is an oil leakage prevention coating. As the type of the resin coating, besides the Teflon coating, for example, NTN Corporation FL7075,
There are FE7090, 7092, etc., all of which are Teflon-based coating agents. The type of oil contained in the bearing or contained in the bearing holder can be, for example, machine oil. The bearings are cylindrical metal bearings or brass and plastic bearings.

[0051]

As described above, according to the present invention,
It is possible to prevent the bearing oil from leaking, prevent the rotor shaft from coming off the stator side, and withstand greater external impact.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a preferred embodiment 1 of a disk drive device of the present invention.

FIG. 2 is an exemplary plan view of the disk drive device of FIG. 1 viewed from a direction E;

FIG. 3 is a view showing a bearing holder, a bearing, a shaft, a rotor stopper, and the like of the disk drive device of FIG. 1;

FIG. 4 is an exploded perspective view of FIG. 3;

FIG. 5 is a view showing an example of a jig for mounting a ring-shaped attached member of a rotor stopper.

FIG. 6 shows a second embodiment of the disk drive device of the present invention.
FIG.

FIG. 7 is a plan view seen from a direction E in FIG. 6;

FIG. 8 is a view showing a shaft, a bearing holder, and a rotor stopper of the disk drive device of FIG. 6;

FIG. 9 is a diagram showing an example of how oil leakage can be prevented by a Teflon coating which is an oil leakage prevention coating.

FIG. 10 is a sectional view showing a third embodiment of the disk drive device of the present invention.

FIG. 11 is a plan view seen from a direction E in FIG. 10;

FIG. 12 is a diagram showing a rotor stopper and a shaft in the disk drive device of FIG. 10;

FIG. 13 shows an axis in the disk drive device of FIG.
The figure which shows a bearing holder and a rotor stopper.

FIG. 14 is a sectional view showing a fourth embodiment of the disk drive device of the present invention.

FIG. 15 is a plan view seen from a direction E in FIG. 14;

FIG. 16 shows an axis in the disk drive device of FIG.
The figure which shows a bearing holder, a rotor stopper, etc.

FIG. 17 is a diagram showing another embodiment of the bearing holder of the disk drive device of the present invention.

FIG. 18 is a diagram showing a conventional disk drive device.

[Explanation of symbols]

1 ... Disk drive device, 10 ... Motor, 1
4 ... rotor, 16 ... stator, 20 ... shaft,
Reference numeral 30: turntable (mounting portion), 60: bearing holder, 70: bearing, 100: shaft retaining member, 110: one end of the bearing holder, 11
2 ... Opening of bearing holder, 114 ... Other end of bearing holder, 120 ... Rotor stopper, 13
0: ring-shaped mounting member, 140: ring-shaped attached member, 150: contact surface of rotor stopper,
..Disks (disk-shaped information recording media, objects to be mounted)

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) F16C 33/10 F16C 33/10 Z (72) Inventor Koichi Yazaki 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Incorporated (72) Inventor Rikuhiro Hanai 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo F-term in Sony Corporation (reference) 3J011 AA07 AA11 BA04 JA02 KA02 KA03 MA23 5D109 BB01 BB12 BB14 BB18 BB21 BB22 5H605 AA02 AA20 BB05 BB19 CC04 CC10 DD07 DD13 EA02 EA10 EB10 EB15 EB28 GG10 5H621 GA01 HH01 JK17 JK19

Claims (12)

[Claims] 1. A motor having a stator and a rotor that rotates with respect to the stator when energized, the rotor comprising: a mounting portion for mounting an object to be mounted; a shaft fixed to the mounting portion; A shaft retaining member fixed in the middle of the shaft,
A bearing that rotatably supports the shaft of the rotor, a bearing holder that fixes the bearing inside, has an opening at one end, and is closed at the other end, The shaft has a hole therethrough, is fixed to the one end of the bearing holder, closes the opening of the bearing holder, and the shaft comes into contact with the retaining member of the shaft of the rotor so that the shaft is the bearing holder. A rotor stopper for preventing the motor from slipping out of the motor. 2. The oil in the bearing holder is filled with the oil in the bearing holder on the inner peripheral surface of the rotor stopper forming the hole through which the shaft passes and on the outer peripheral surface of the shaft corresponding to the inner peripheral surface. The motor according to claim 1, further comprising an oil leakage prevention coating for preventing leakage from between an inner peripheral surface of the shaft and the outer peripheral surface of the shaft. 3. The motor according to claim 1, wherein the oil leakage prevention coating is the resin coating. 4. The motor according to claim 1, wherein the rotor stopper has an air vent hole connecting the inside of the bearing holder and the outside of the bearing holder. 5. The motor according to claim 1, wherein the rotor stopper and the shaft retaining member have a ring shape. 6. A ring-shaped mounting member fixed to said one end of said bearing holder, said rotor stopper being:
A ring-shaped accessory member fixed to the mounting member and forming the hole through which the shaft passes, wherein the oil leakage prevention coating is applied to the inner peripheral surface of the ring-shaped accessory member. Item 3. The motor according to Item 2. 7. A motor having a stator and a rotor that rotates with respect to the stator when energized,
A disk drive device that rotates a disk-shaped information recording medium together with the rotor, wherein the rotor of the motor includes a mounting part for mounting the disk-shaped information recording medium, a shaft fixed to the mounting part, A shaft retaining member fixed in the middle of the shaft, wherein the stator of the motor has a bearing rotatably supporting the shaft of the rotor; and A bearing holder having an opening and the other end closed, and having a hole through which the shaft passes, fixed to the one end of the bearing holder to close the opening of the bearing holder, A disk stopper device, comprising: a rotor stopper for preventing the shaft from coming out of the bearing holder when the stopper member of the shaft comes into contact with the rotor stopper. 8. The oil inside the bearing holder is filled with the rotor stopper on the inner peripheral surface of the rotor stopper forming the hole through which the shaft passes and on the outer peripheral surface of the shaft corresponding to the inner peripheral surface. 8. The disk drive device according to claim 7, further comprising an oil leakage prevention coating for preventing leakage from between the inner peripheral surface of the shaft and the outer peripheral surface of the shaft. 9. The disk drive according to claim 7, wherein the oil leakage prevention coating is the resin coating. 10. The disk drive device according to claim 7, wherein said rotor stopper has an air vent hole connecting the inside of said bearing holder and the outside of said bearing holder. 11. The disk drive device according to claim 7, wherein said rotor stopper and said shaft retaining member are ring-shaped. 12. The rotor stopper, comprising: a ring-shaped attachment member fixed to the one end of the bearing holder; and a ring-shaped attachment member fixed to the attachment member and forming the hole through which the shaft passes. 9. The disk drive device according to claim 8, wherein the oil leakage prevention coating is applied to the inner peripheral surface of the ring-shaped attachment member. 10.