JP2001095213A - High-speed spindle motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-speed spindle motor, incorporating a stator assembly containing a stator having many conductors which generate a plurality of magnetic fields, when electric currents are supplied to the conductors in a state where the stator is substantially sealed with a thermoplastic plastic, and a main body made of a phase-changing material. SOLUTION: In a high-speed spindle motor 10, a freely rotatable hub 12 connected with a magnet 28 is brought close actively to a stator 20. The motor 10 further incorporates a shaft 16 and a bearing 18 surrounding the shaft 16, in such a state where either the shaft 16 or bearing 18 is fixed to a stator assembly 13, and the bearing 18 or the shaft 16 is fixed to the hub 12. Methods for developing and forming the motor and a hard disc drive device is discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates generally to high-speed motors. More particularly, the present invention relates to a spindle motor as used in a hard disk drive, and a structure and configuration of a spindle motor for aligning and holding respective components of the motor, and a hard disk drive using the motor and the motor. The present invention relates to a stator assembly for use in an apparatus and a method for developing and manufacturing a high-speed motor.

[0002]

2. Description of the Related Art Computers generally use disk drives for storage purposes. Disk drives include a stack of one or more magnetic disks. This stack rotates and is accessed using a head or read-write transducer. Typically, a disk is rotated using a high-speed motor such as a spindle motor.

FIG. 1 shows an example of a conventional spindle motor 1. The motor 1 has a base 2, a stator 4, a shaft 6, a bearing 7, usually made of die-cast aluminum.
It includes a disk support member 8, also called a hub. The magnet 3 and the magnetic flux return ring 5 are mounted on the disk support member 8. The stator 4 is separated from the base 2 using an insulator (not shown), and is attached to the base 2 using an adhesive. Separate structures for receiving the bearings 7 are formed on the base 2 and the disk support member 8. One end of the shaft 6 is inserted into a bearing 7 positioned on the base 2, and the other end of the shaft 6 is arranged on a bearing 7 arranged on a hub 8. A separate electrical connector 9 is also inserted into the base 2.

Each of these components must be fixed with respect to each other with a certain tolerance. Accuracy in these tolerances can greatly enhance motor performance.

[0005] In operation, the disk stack is placed on a hub. The stator windings are selectively energized and interact with the permanent magnet to rotate the hub as desired. When the hub 8 rotates, the head engages in a read operation or a write operation based on a command from the CPU of the computer.

Disk drive manufacturers are constantly seeking to improve the speed at which data can be accessed. This speed is determined to some extent by the speed of the spindle motor.
This is because current magneto-resistive head technology can access data at speeds faster than the fastest currently manufactured spindle motors can provide. The speed of the spindle motor depends on the dimensional accuracy or tolerance between the various components of the motor. When the dimensional accuracy between the components is increased, the gap between the stator 4 and the magnet 3 is reduced, generating a larger force, providing more torque, increasing acceleration, and increasing the rotation speed. can do. One disadvantage of conventional spindle motors is that they require a number of separate parts to secure the motor components together. This builds up tolerances, thereby reducing overall dimensional accuracy between components. The stack of tolerances is referred to as the sum of all changes in tolerance for all components, as well as the total tolerance for alignment of components to each other.

In an effort to increase the speed of the motor, some hard disk manufacturers have used hydrodynamic bearings. However, these hydrodynamic bearings differ in aspect ratio from conventional bearings. One example of different aspect ratios can be found in cylindrical hydrodynamic bearings where the length of the bearing is greater than its diameter. This increases the potential for problems due to differences in the coefficient of thermal expansion from other metals used in existing spindle motors, and increases the size between the hydrodynamic bearing and other metal parts of the motor. It becomes difficult to maintain accuracy over the operating temperature. Hydrodynamic bearings are less rigid than conventional ball bearings, and therefore have a greater likelihood of inaccurate rotation when subjected to vibration or shock. An important feature of hard disk drives is the amount of information that can be stored on the disk. One way to increase the amount of information stored on a disc is to make the data tracks closer together. Currently, this spacing between the information parts is limited by vibrations that occur during operation of the motor. These vibrations are caused by the occurrence of vibration of a specific frequency when the stator winding is energized. Furthermore, these vibrations are caused by the harmonic oscillation of the rotating hub and disk.
oc oscillations). Harmonic oscillations are primarily caused by the media disks being unequal in size.

An important factor in motor design is reducing the operating temperature of the motor. As the temperature of the motor rises, the electrical efficiency of the motor and the life of the bearing are adversely affected. As the temperature increases, the sum resistance loss increases, thereby reducing the overall output of the motor. Further, the Algenis equation predicts that the failure rate of an electrical device is exponentially related to its operating temperature. The frictional heat generated by the bearing increases with speed. In addition, the bearings become hot when expanded,
The bearing cage is stressed and possibly deformed, causing uneven rotation, resulting in higher heat,
Due to the uneven rotation, it is necessary to further increase the distance between the data tracks, thereby shortening the life of the bearing. One drawback of existing motor designs is the limited heat dissipation effect and the difficulty of incorporating a heat sink to assist heat dissipation. Furthermore,
In current motors, the operating temperature generally increases as the motor gets larger.

[0009] Manufacturers impose strict requirements on the gassing of materials used inside hard disk drives. These requirements seek to reduce the emission of material adhering to the magnetic medium or head during operation of the drive. The main objects are the adhesive used to attach the components together, the varnish used to insulate the wires, and the epoxy used to protect the steel laminate from oxidation.

Further, in addition to such a gas generating material, the head is damaged by airborne particles in the driving device. Furthermore, airborne particles in the disk drive may interfere with the exchange of signals between the read / write head and the medium. To reduce the effects of potential airborne particles, hard drives are manufactured to achieve clean room standards, and air filters are installed inside the drive to reduce contamination levels during operation.

The head used in the disk drive is
Damage can be caused by electrical shorts through small gaps between the media and the head surface. To prevent such short circuits, some hard drives use a plastic or rubber ring to insulate the spindle motor from the hard disk case. The disadvantage of this design is that extra components are required.

Another example of a spindle motor is shown in US Pat. No. 5,694,268 (Danfield et al.).
(Referring to the patent, the disclosure of that patent is incorporated herein.) Referring to FIGS. 7 and 8 of this patent, the stator 200 of the spindle motor is overmolded. Type (overmold) 20
9 is enclosed. The overmolded stator has an opening through which a mounting pin 242 passes for mounting the stator 200 to the base. US Patent 5,
No. 672,972 (Visco Chill) discloses a spindle motor having an overmolded stator.
(By touching the patent, the contents disclosed in that patent are incorporated herein.) One drawback of the overmolds used in these patents is that That is, the coefficient of linear thermal expansion ("CLTE") is different from that of the corresponding metal part. Another disadvantage of overmolds is that heat dissipation is not as effective. Furthermore, the overmolds shown in these patents were not effective at attenuating the vibrations generated by energizing the stator windings. US Patent No. 5,80
No. 6,169 (Trago) discloses a method of manufacturing an injection-molded motor assembly. (By touching the patent, the contents disclosed in that patent are incorporated herein.) However, the motor disclosed in Trago is a step motor, not a high-speed spindle motor, It is not used in such hard disk drive applications.

[0013]

Thus, there is a need for an improved high speed spindle motor which has properties particularly useful in hard disk drives and which solves the above-mentioned problems.

[0014]

SUMMARY OF THE INVENTION A high speed motor has been invented which solves many of the above problems. In addition, unique stator assemblies and other components of high speed motors have been invented, as well as methods of manufacturing and developing motors and hard disk drives. In one aspect, the invention relates to a high-speed spindle motor, comprising: a) a stator assembly, i) a stator having a number of conductors that generate a plurality of magnetic fields when current is passed; and ii) a stator. A) a stator assembly including a body of phase change material to be encapsulated; b) a rotatable hub with a magnet operatively connected to the stator; c) a shaft;
E) a high speed spindle motor having a bearing around a shaft, e) one of the shaft or bearing being fixed to the stator assembly and the other of the shaft or bearing being fixed to a rotatable hub. Provided.

According to a second aspect of the present invention, there is provided a high-speed spindle motor comprising: a) a stator substantially enclosed in a thermoplastic body having a cylindrical hole; b) a bearing press-fitted into the hole; c) a bearing. A high speed spindle motor including a shaft rotatably supported by the shaft and d) a hub fixed to the shaft to which the magnet is coupled.

According to another aspect of the invention, there is provided a high speed spindle motor for a disk drive, comprising: a) a shaft;
b) a disk support member containing permanent magnets attached to the shaft; c) a bearing surrounding the shaft; d)
A high speed spindle motor is provided, comprising: a stator; and e) a monolithically formed body substantially enclosing the stator, wherein the body is configured to align the shaft, disc support members, and bearings with respect to each other. You.

According to still another aspect of the present invention, there is provided a high-speed spindle motor for a disk drive, comprising: a) a shaft;
b) a disk support mounted on the shaft, c)
A high speed spindle motor comprising a bearing disposed around a shaft, d) a stator, and e) a monolithically formed body substantially enclosing the stator, wherein the monolithically formed body surrounds the bearing and the shaft. Provided.

According to still another aspect of the present invention, there is provided a high-speed motor for a disk drive, comprising: a) a shaft; b) a disk support member concentrically positioned with respect to the shaft;
c) a bearing disposed between the disk support member and the shaft, d) a stator, and e) a monolithically formed body substantially enclosing the stator, wherein the monolithically formed body surrounds the bearing. A high speed motor is provided that is concentrically positioned on the shaft and the monolithically formed body substantially surrounds the shaft.

In still another aspect of the invention, a method of manufacturing a high speed motor for a disk drive includes the steps of: a) providing a shaft; b) providing a disk support; and c) providing a bearing. D) providing a stator with a number of conductors that generate a plurality of magnetic fields when current is passed; and e) a monolithic body substantially encapsulated with the phase change material and having an interior portion. And f) disposing the bearing and shaft in the inner portion; and g) attaching the disk support member to the shaft.

According to yet another aspect of the invention, there is provided a method of developing a high speed motor for an apparatus, comprising: a) a body made of a first phase change material, comprising a plurality of conductors that generate a plurality of magnetic fields when current is passed. Providing a stator substantially encapsulated therein; b) providing the stator with a bearing, a shaft,
Assembling components to be rotated by a motor to form a device; c) energizing the stator, rotating the components to generate vibration, and measuring the frequency of the vibration; d. E) repeating a step of designing a second phase change material for attenuating vibration generated by the bias of the stator, and e) steps a), b) and c), and replacing the first phase change material with the second phase change material. Using the material to adjust at least one of the flexural modulus, elongation, and surface strength properties of the phase change material between the first and second phase change materials to optimize vibration damping. Performing the steps of:

In yet another aspect of the invention, a stator assembly includes: a) a magnetically inductive core; b) a plurality of conductors proximate the core to induce a magnetic field in the core when current is passed; A stator assembly is provided that includes a body substantially encapsulating a core and a conductor, the body comprising a phase change material having a coefficient of linear thermal expansion substantially equal to the coefficient of linear thermal expansion of the core.

In yet another aspect of the invention, a stator assembly includes: a) a stator having a number of conductors that generate a plurality of magnetic fields when current is passed; and b) a heat transfer substantially encapsulating the conductors. A stator assembly is provided that includes a body of a phase change material having a rate of at least 0.7 watts / (meter · K) and a dielectric strength of at least 250 volts / mil (9842.52 v / mm).

In yet another aspect of the invention, in a motor and disk assembly, the motor includes: a) a stator having a number of conductors that generate a plurality of magnetic fields when current is passed; and b) a conductor. Substantially encapsulating, monolithic body of phase change material, the phase change material having the same stator without encapsulated harmonic oscillations in the range of 300 Hz to 2000 Hz of the motor and disk assembly. A motor and disk assembly is provided that has a vibration damping effect that is reduced by at least 5 dB compared to a motor.

In still another aspect of the invention, in a motor / disk assembly, the motor includes: a) a stator having a number of conductors that generate a plurality of magnetic fields when current is passed; and b) a conductor. A substantially encapsulated, monolithic body of phase change material, wherein the phase change material reduces the audible noise of the motor / disk assembly by at least 2d compared to a motor having the same unencapsulated stator.
A motor and disk assembly having a B-decreasing vibration damping effect is provided.

According to yet another aspect of the invention, there is provided a method of manufacturing a hard disk drive, comprising: a) forming a stator including a steel laminated core and wire windings; and b) placing the stator in a body made of a phase changing material. Practically encapsulated,
Forming a stator assembly; c) ultrasonically cleaning the stator assembly; d) assembling the stator assembly with bearings, shafts and hubs to form a spindle motor; and e) driving the spindle motor to a hard disk drive. And assembling.

According to yet another aspect of the present invention, there is provided a method for manufacturing a spindle motor, comprising the steps of: a) manufacturing a laminated steel core, wire windings, and terminals to a stator; Encapsulating and forming a stator assembly; and c) incorporating the stator assembly into a spindle motor, the spindle motor providing a method that meets the particle emission standards of the hard disk drive manufacturing industry.

According to yet another aspect of the present invention, there is provided a method of manufacturing a hard disk drive having a high data density, comprising the steps of:
Forming a spindle motor having reduced vibration characteristics, the method comprising: i) a stator assembly including a stator substantially encapsulated in a body made of a phase changing material; i.
i) a rotatable disk support member to which a magnet is connected, i
ii) a shaft, iv) a bearing surrounding the shaft, and v) a spindle motor in which one of the shafts or bearings is fixed to a stator assembly and the other of the shafts or bearings is fixed to a rotatable disk support member. B) incorporating a spindle motor into a hard disk drive having a magnetic storage medium on a disk support member; And the step of obtaining by the method.

In still another aspect of the invention, a high speed spindle motor includes: a) a stator assembly; b) a rotatable hub having a magnet operatively connected to the stator; c) a shaft; and d) a shaft. , Wherein one of the bearings or shafts is fixed to the stator assembly and the other of the bearings or shafts is fixed to the hub.

According to yet another aspect of the invention, there is provided a method of manufacturing various spindle motors, comprising the steps of: a) providing a plurality of stators having magnetic poles with windings, the stators comprising: The number of turns of the wire, ii)
Providing a plurality of stators, wherein one or more of the number of poles, iii) the diameter of the stator, and iv) the thickness of the stator are different, b) providing a common forming tool. C) holding the first stator in the molding tool and adding a phase changing material to substantially enclose the first stator; d) using the encapsulated stator, bearings and shaft, E) holding a second stator having different characteristics from the first stator in a mold, adding a phase changing material to substantially enclose the second stator, and f) enclosing the second stator. Using the second stator, bearing and shaft
A method of forming a motor of the type described above.

According to yet another aspect of the invention, a hard disk drive includes: a) substantially enclosing the stator;
A) a base assembly including a body of phase change material that supports the shaft; b) a hub rotatably supported on the shaft by bearings, wherein the magnet is operatively connected to the stator; Access to one or more disks and d) data
A hard disk drive is provided that includes a read / write head that records data on or reads data from one or more disks.

The present invention provides these and other features,
The advantages of the present invention will become more apparent from the following detailed description, in which the presently preferred embodiments are read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIGS. 2, 3 and 4 show a first embodiment of a high-speed motor according to the present invention. The term "high speed" means that the motor runs at 5000r
pm or higher. The spindle motor 10 is designed to rotate a single disk or a stack of disks or disk stacks of a computer hard disk drive. The motor 10 is formed using an encapsulation method that reduces the number of parts required to manufacture the motor as compared to conventional motors used in disk drives, thereby accumulating tolerances and manufacturing costs. And provide other advantages discussed below.

Referring to FIG. 2, first, a stator 20 is formed using a conventional steel laminate 11 forming a magnetically inductive core 17 having a plurality of magnetic poles 21 and wire windings 15 serving as conductors. . The conductors generate a plurality of magnetic fields in the core by induction or the like when current flows through these conductors. In this embodiment, a magnetic field is induced in each of the magnetic poles 21.

Next, the remainder of the spindle motor 10 is formed using the stator 20 (see FIG. 3). The spindle motor 10 includes a hub 1 serving as a disc support member.
2, including the stator 20 and the main body 14. Stator 20
And the body 14 together form the stator assembly 13. The body 14 is preferably a monolithic body 14.
It is. Monolithic is defined as being formed as a single component. The body 14 substantially encloses the stator 20. Substantially encapsulating means that the body 14 completely surrounds the stator 20 or substantially all but a small area of the stator that may be exposed. However, substantially encapsulating means that the body 14 and the stator 20 are firmly fixed to each other and behave as a single component with respect to harmonic oscillation.

The body 14 is preferably formed of a phase changing material. A phase change material is a material that can be used in a liquid phase to surround a stator, but later changes to a solid phase. There are two types of phase change materials that are most useful in practicing the present invention, temperature activated and chemically activated. The temperature-activated phase change material melts at a high temperature and solidifies at a low temperature. However, to be practical, the phase change material must melt at a low enough temperature that it can be used to encapsulate the stator. Preferred temperature activated phase change materials solidify at a temperature in the range of 93 ° C to 371 ° C (about 200 ⁰ F to 700 ⁰ F). The most preferred temperature activated phase change material is a thermoplastic. The preferred thermoplastic melts at a temperature at which it can be injection molded and solidifies at the normal operating temperature of the motor. Body 1 that changes phase by chemical reaction
An example of a phase change material that can be used to form 4 is epoxy. Other suitable phase change materials can be classified as thermoset materials.

As shown in FIG. 4, the shaft 16 is connected to the hub or disk support member 12 and
Are surrounded by a bearing 18 adjacent thereto.
A rotor or magnet 28 is fixed on the flange inside the hub 12 for operation near the stator. The magnet 28 is preferably a permanent magnet as described below. The main body 14 includes a base 22. Further, terminals including mounting means such as holes 25 and a connector 26 for connecting the conductor to an external power supply are formed as parts of the stator assembly. The terminal 26 is partially enclosed in the main body 14.

Referring to FIGS. 3 and 4, the entire base 22 of the main body 14 is connected to a hard drive case (not shown). The base 22 may be fixed to the hard drive case using a connecting member (not shown) such as a screw. On this occasion,
The hole 25 shown in FIG. 3 is used. In another aspect, other types of attachment means, such as connecting pins or lugs, can be formed as part of the base 22. The connector 26 is preferably a through-hole pin type connector 26 and is connected through a hard drive case to a control circuit board provided on an outer surface of a base (not shown). In another aspect, the connector may be a flexible circuit with copper pads that allow for spring contact interconnection.

The stator 20 is provided inside the main body 4 with the internal portion 3.
It is positioned in a direction substantially perpendicular to zero. Referring to FIG. 2, the stator 20 is preferably annular in shape,
It has an open central portion 32. The magnetic pole 21 extends radially outward from the central portion 32. The surface of the magnetic pole 21 is positioned outward with respect to the central portion 32 of the stator 20. The body 14 is molded around the stator 20 such that the pole faces are exposed and are surrounded by the disk support member 12 and are concentrically aligned with the disk support member. In another aspect, the entire pole is encapsulated within body 14 and is not exposed.

Referring to FIG. 4, the body 14 has an upper portion 40 extending upward from the stator 20. Further, the upper portion 40 is preferably annular in shape. Body 14 includes an inner portion 30. The inner portion 30 is sized and shaped to accommodate the bearing 18 as a whole. Inner portion 30 includes an upper support portion 42 and a lower support portion 44. In the embodiment of FIG. 4, the inner part 30 is preferably cylindrical in shape.

The phase change material used to form body 14 is preferably a thermally conductive but non-conductive plastic. Further, the plastic preferably contains ceramic-filled particles that increase the thermal conductivity of the plastic. A preferred form of plastic is polyphenylsulfide (PPS) sold under the trademark "Conduit" by LNP. OTF-212
Is particularly preferred. Examples of other suitable thermoplastics include 6,6-polyamide, 6-polyamide,
4,6-polyamide, 12,12-polyamide, 6,1
2-polyamide, polyamide containing aromatic monomer, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, aromatic polyester, liquid crystal polymer, polycyclohexane, dimethylol terephthalate, copolyetherester, polyphenylene sulfide, polyacryl Acids, polypropylene, polyethylene, polyacetals, polymethylpentene, polyetherimides, polycarbonate, polysulfone, polyethersulfone,
Examples include, but are not limited to, polyphenylene oxide, polystyrene, styrene copolymers, mixtures and graft copolymers of styrene and rubber, and glass reinforced or impact resistant resins. In this embodiment, a mixture of these resins, such as a mixture of polyphenylene oxide and polyamide,
And mixtures of polycarbonate and polybutylene terephthalate.

Referring to FIG. 4, bearing 18 includes an upper bearing 46 and a lower bearing 48. Further, each bearing 18 has an outer surface 50 and an inner surface 52. The outer surface 50 of the upper bearing contacts the upper support portion 42 and the outer surface 50 of the lower bearing 48 contacts the lower support portion 44. The inner surface 52 of the bearing 18 contacts the shaft 16. The bearing is preferably annular in shape. Bearing 1
The inner surface 52 of 8 is press-fitted to the shaft 16. An adhesive may be used. Outer surface 5 of bearing 18
0 is press fitted into the inner part 30 of the body 14. An adhesive may be used. The bearing of the embodiment shown in FIGS. 3 and 4 is a ball bearing. In other aspects, other types of bearings can be used, such as hydrodynamic bearings or a combination of hydrodynamic and magnetic bearings. These bearings are typically made of stainless steel.

The shaft 16 is connected to the inner part 30
Are concentrically arranged within. The bearing 18 surrounds a portion of the shaft 16. As described above, the inner surface 52 of the bearing is in contact with the shaft 16. Shaft 16 includes an upper portion 54 and a lower portion 56. The upper portion 54 of the shaft 16 is fixed to the hub 12. The lower portion 56 of the shaft 16 is free to rotate within the lower bearing. Thus, in this embodiment, the shaft 16 is free to rotate with respect to the body 14. Shaft 1
6 is preferably cylindrical in shape. The shaft 16 is preferably made of stainless steel.

Referring to FIG. 4, the hub 12 includes a main body 14.
It is arranged concentrically around the center. The hub 12 is fixed to a shaft 16 and is separated from the main body 14. Hub 12 includes a magnetic flux return ring 58 and magnet 28. The magnetic flux return ring 58 is bonded to the disk support member. The magnet 28 is bonded to the hub 12. As shown in FIG. 4, the magnet 28 is
Is surrounded concentrically. In this embodiment, the magnet 2
8 and the stator 20 are assembled when the motor 10 is assembled.
They are almost in the same plane.

The magnet 28 is preferably a sintered part,
One solid piece. Place the magnet 28 on the magnetizing device,
The magnetizing device forms a plurality of separate north and south poles on the magnet 28 according to the number of magnetic poles 21 provided on the stator 20. The flux return ring 58 is preferably made of magnetic steel. The hub is preferably made of aluminum. Further, the hub may be formed of a magnetic material instead of the magnetic flux return ring. Operation of the First Embodiment In operation, the spindle motor shown in FIGS. 3 and 4 is driven by supplying electric pulses to the connector 26. Using these pulses, the winding 15 around the magnetic pole 21 of the stator 20 is selectively energized.
This generates a moving magnetic field. This magnetic field is
Interacts with the generated magnetic field to rotate the magnet 28 about the body 14. As a result, the hub 12 is
Start rotation with. The bearing 18 facilitates rotation of the shaft 16.

A disk or disk stack (not shown) placed on the hub is rotated when the hub 12 rotates. Then, a head (not shown) reads the data from the disk and writes the data to the disk. Manufacturing Method of First Embodiment The spindle motor 10 shown in FIGS. 3 and 4 is partially manufactured using a sealing technique. This encapsulation technology
The process includes the steps described below, and uses the mold shown in FIGS. First, a mold for manufacturing a part having a desired shape is formed. The mold has two halves 72 and 74. Further, the hydraulic cylinder 7 in the molding tool
The core pin 76 is connected to a plate 78 operated by the. Place the stator 20 in the mold and close the two halves. The core pins hold the stator 20 in its correct position. Second, using solid state process control injection molding, plastic is injected around the stator through the gate 80 to encapsulate the stator and form the body 14 having the shape shown in FIGS. The pin 76 retracts during the inflow of plastic, so that the plastic completely surrounds the stator.

After the formation of the stator assembly, the shaft 16 is press-fitted and bonded to the bearing. Next, an adhesive is applied to the outer surface of the bearing, and the bearing and shaft are press-fitted to the inner portion 30 of the plastic body 14. Forming the inner part 30 smaller than necessary,
It is desirable to drill after the molding process to match the exact size of the bearing used. Next, the disk support member 12 made of aluminum is machined, and the magnet and the magnetic flux return ring are bonded to the lower surface. Next, the disk support member 12 is bonded to the motor shaft.

After assembling the spindle motor and the hub, they can be used to form a hard disk drive, and the holes 25 are used to attach the motor to the base of the hard disk drive. Thereafter, formation of the hard disk drive can be performed in the following conventional manner. Advantages of the First Embodiment One advantageous feature of the first embodiment is provided by the fact that the body 14 is preferably a monolithic body 14, ie is monolithically formed using encapsulation technology. The monolithic body 14 provides a single structure that aligns the stator, bearing, shaft, and disk support relative to each other. (Furthermore, this single piece provides support for the bearing and base 22 so that it can be coupled to a hard disk drive.) Tolerances build up due to the large number of components used in conventional devices. , The manufacturing cost increases. vice versa,
The use of a single body of the present invention provides alignment of the components of the spindle motor and connection of these components to one another. By encapsulating the body 14, and thereby molding some components as parts of the body 14, and using the body to align the remaining components, the stacking of tolerances is greatly reduced. Accordingly, manufacturing costs are greatly reduced. Furthermore, this greatly improves the efficiency and performance of the motor.

The disclosed spindle motor optimizes dimensional tolerances between motor components, thereby increasing rotational speed. Because the preferred body is made of a thermoplastic, any type of thermoplastic having a CLTE similar to a steel bearing case can be used. This facilitates an optimal interference fit between the motor body and a bearing such as a hydrodynamic bearing. Heretofore, it has been difficult to achieve such an interference fit due to differences in the coefficient of thermal expansion between the bearing and the steel part of the motor. When the motor heats up and the bearing becomes hot, stress is applied to the bearing case. This is because the bearing case is about to expand. The bearing case is
In some cases, it deforms, causing uneven rotation. this is,
Limit how close data tracks can be to each other.

Further, in order to prevent seizure when the motor becomes high in temperature, a gap between the magnet 28 and the stator 20 is set so that the magnet 28 does not come into contact with the stator 20 when the piece is expanded by heating. Is larger than the desired size. When the magnet comes into contact with the stator, the contact generates magnet particles, which damage the head and impair the performance of the head for reading data from the disk or recording data on the disk. CLTE of main body
If is larger than the steel laminate of the stator, the gap does not allow the body to contact the rotating magnet even if the body expands due to motor heating (even if the steel laminate is unlikely to contact the magnet) Must be large enough. In a preferred embodiment of the present invention, the CLTE of the body is matched to the steel laminate by 0.127 mm (0.005 mm).
Inches), more preferably 0.0762 mm (0.
003 inches).
When the body expands, the body expands at the same rate as the laminate and does not expand to the point where the body zeros the size of the gap. Thus, only enough clearance is needed for expansion of the steel laminate. These small gaps make the motor more efficient. This is because the larger the distance between the stator and the rotating magnet, the lower the electric efficiency of the motor.

In using the present invention, a particular plastic with Rockwell hardness, flexural stiffness, and elongation properties specifically designed to oppose the vibration frequency generated by the motor is selected for body 14. Was done. Thus, the disclosed spindle motor greatly reduces motor vibration. By reducing the vibrations in this manner, information can be stored closer to one another on the disk, thereby increasing data density.

As discussed above, it was difficult to radiate heat with the conventional spindle motor. To encapsulate the body 14, certain plastics designed to promote heat dissipation can be selected. By bringing this material into intimate contact with the two heat sources (motor windings and bearings) and forming a solid heat conduction path to the drive housing, the overall motor temperature can be reduced. Further, conveniently, a heat sink can be enclosed within the body 14 during the molding process. These heat sinks include a metal insert, discussed in detail below. Because these inserts are encapsulated within the body rather than separately mounted, the manufacturing process is simplified, and later machining allows for more precise tolerances and dimensional accuracy over the life of the motor. Be maintained.

In addition, the disclosed spindle motor reduces the emission of material from the motor components onto the magnetic media or head of the disk drive. this is,
This is obtained because components such as stators that may emit such material are substantially encapsulated in plastic. The use of a monolithic body 14 eliminates the use of adhesives or other materials used to attach components to one another.

In addition, the disclosed spindle motor may be used to isolate the spindle motor from the hard drive to prevent short circuits from traveling to the magnetic media and ultimately to the read-write head. Eliminates the need for a separate plastic or rubber ring. The disclosed spindle motor body 14 is preferably non-conductive (at least 250 volts / mil (9842.52 v /
mm), and is made of a thermoplastic material that can be injection molded, so that such a separate rubber insulating ring is unnecessary. In this case too, the increase in manufacturing costs and the accumulation of tolerances associated with the use of additional components is thereby suppressed. Second Embodiment Referring to FIGS. 5 and 6, these figures show a second embodiment of the spindle motor 110. FIG. This embodiment is similar to the embodiment shown in FIGS. 2, 3, and 4,
Similar components have the same reference numbers plus 100. The monolithic body 114 is formed by an encapsulation method. The main difference between the first embodiment and the second embodiment is that in the second embodiment, when the motor 110 is assembled, the magnet 128 is concentrically surrounded by the stator 120 and the stator 20 surrounds the magnet 28. First
This is the opposite of the embodiment. Further, the body 114 is formed in a different manner to effect this positioning. Referring to FIG. 6, the main body 114 includes a stator 120.
Is concentrically surrounding a portion of the body that surrounds shaft 116 and is shaped such that a gap 160 is formed between the two portions. Further, with such positioning, the magnet 128 is positioned on the outer portion of the hub and the flux return ring 158 is
28.

In the embodiment shown in FIGS. 5 and 6, a hydrodynamic bearing 118 is used. The hydrodynamic bearing may be an air bearing. The fluid used in the hydrodynamic bearing can be either a liquid or a gas. Bearings 118 concentrically surround most of the shaft. In another aspect, a ball bearing as shown in the first embodiment can be used in the second embodiment.
Finally, in the second embodiment, the inner part 1 of the main body 114 is
Although 30 does not extend the full length of body 114, it may be so in other embodiments. Second
The embodiment can be manufactured and used in the same manner as the first embodiment. This embodiment has the advantages described above in connection with the first embodiment. Hydrodynamic bearings can be used because of the low stress acting on the bearing case and the ease of assembly of this motor. The use of hydrodynamic bearings results in low friction, low wear resistance, and therefore long bearing life, low vibration and higher speed operation. Third Embodiment Referring to FIG. 7, FIG.
An example is shown. This embodiment is similar to the embodiment shown in FIGS. 5 and 6, and similar components have been given the same reference numbers with 200 added. Monolithic body 2
14 is formed by a sealing method. In a third embodiment, the hub 212 is made of steel, so that a flux return ring 258, which must be made of a material that transmits magnetic energy, can be formed as the remaining extension of the hub. Magnet 228 is fixed to magnetic flux return ring 258.

The third embodiment illustrates the use of an insert. In general, the term "insert" is used to describe any component other than the elements of the stator substantially encapsulated within the phase change material with the stator. Different inserts can be used to provide different advantages.
The insert can be used to provide enhanced structural stiffness, thermal conductivity, vibration damping, or magnetic effects. The insert may itself be magnetic. These second magnets may be reinforcing magnets directly associated with the electromagnetic function of the motor or may be parts of a magnetic bearing (described in more detail below). The insert can enhance heat dissipation from the bearing and the stator. This insert can improve the damping of motor vibration. This reduces audible noise, improves motor life, and reduces data track spacing.

In the embodiment of FIG. 7, two inserts are provided. Specifically, a central insert 260 is molded into the upper portion 240 of the body 214. This central insert 26
0 is concentrically shaped with respect to the upper portion 240. A base insert 262 is molded into the base portion 222 of the body 2114. The center insert 260 and the base insert 262 help increase the rigidity of the body 214. These inserts further improve the thermal conductivity of the body 124 as a whole, thereby improving the performance of the motor. Furthermore, to attenuate unwanted vibrations or audible noise,
Inserts can be used in combination with inclusion bodies. The plastic body 214 locks the insert in place with a high degree of strength. These inserts can be molded so that they are entirely covered by plastic, or other parts of these inserts can be exposed. The third embodiment can be formed and used in the same manner as the first embodiment. In this embodiment, the first
The advantages discussed above in connection with the embodiment and insert 26
There are advantages to using 0 and 262. Fourth Embodiment FIG. 8 shows a fourth embodiment of the spindle motor. The spindle motor 310 includes components similar to those of the above-described embodiment, particularly, the second embodiment shown in FIGS. Monolithic body 314 is formed using an encapsulation method. The main difference between the fourth embodiment and the second embodiment is that the fourth embodiment has a magnetic bearing. Part of the magnetic bearing forms the insert. Referring to FIG.
First magnetic bearing portion 364 is substantially encapsulated within body 314 at a predetermined location above stator 320 by insert molding. The second portion 366 on the opposite side of the magnetic bearing is a flange portion 3 of the disk support member 312.
Attached to 68 hubs. Magnetic bearing 36
The second part 6 is attached to the flange part 368 with an adhesive. First magnetic bearing portion 364 and second
A magnetic bearing portion 366 is used in conjunction with the hydrodynamic bearing to create a working gap inside the hydrodynamic bearing 318 so that there is no wear due to starting conditions. The body 314 can be molded and later machined into the body and / or the magnet to provide precise tolerances between the first and second portions of the magnetic bearing. The advantages of the present invention are obtained by the fact that the first part of the magnetic bearing is substantially encapsulated by the plastic of the body. First, the first part is completely sealed, and the main body is machined to expose the surface of the magnet. Encapsulating the first portion 364 facilitates machining of the magnetic bearing and removal of magnet debris generated by such machining. In the fourth embodiment,
It can be manufactured and used in the same manner as in the first embodiment. This embodiment has the advantages discussed above in connection with the first embodiment as well as the advantages obtained by using magnetic bearings. Fifth Embodiment Referring to FIG. 9, a spindle motor 41 is shown in FIG.
A fifth embodiment of 0 is shown. The fifth embodiment includes components similar to those of the above-described embodiment, particularly, the first embodiment. Monolithic body 414 is formed using an encapsulation method. The main difference between the fifth embodiment and the first embodiment is the fifth embodiment.
That is, the embodiment further includes an insert 468. The insert 468 is preferably annular in shape and the bearing 4
18 and an inner portion 430 of the body 414. The insert 468 is sealed together with the stator 420,
The plastic holds the insert 468 tightly and accurately positioned relative to the stator. Insert 468 is
It is preferably made of stainless steel. Insert 468 increases the strength and rigidity of body 414 as a whole. Furthermore,
The insert 468 improves the thermal conductivity of the body 414. Further, the difference in CLTE from the bearing material is eliminated. Furthermore, bonding to steel bearing materials is easier (similar materials are easier to bond than different materials). In this embodiment, additional inserts can be added, such as the base inserts discussed above. The fifth embodiment is
It can be manufactured and used in the same manner as in the first embodiment. This embodiment has the advantages described above in connection with the first and third embodiments. Sixth Embodiment Referring to FIG.
Ten sixth embodiments are shown. Monolithic body 5
14 is formed using an encapsulation method. This embodiment includes components similar to those of the above-described embodiment, particularly, the first embodiment.
However, the shaft 1 according to the first embodiment, which is mounted on the disk support member 12 and rotates with the support member,
Instead of 6, the shaft 516 of the sixth embodiment is fixed with respect to the thermoplastic body 514 and thus with respect to the stator assembly. The bearing 518 is provided on the disk
2 and the shaft 516. Disc support member 512 includes an inner portion 513 and an outer portion 515. Inner portion 513 is located concentrically between inner portion 530 of body 514 and bearing 518. In operation, the bearing is provided entirely along the inner portion 513 of the disk support member 512 and the fixed shaft 516 does not move with respect to the body 514. In this embodiment, the shaft 516 can be made longer so that it can be fixed to a hard disk drive case (not shown). This feature helps increase the rigidity of the motor and simplifies the construction of the hub and assembly into the motor. A comparison between the first embodiment and the sixth embodiment shows that, in the present invention, either the shaft or the bearing can be fixed to the stator assembly, and the other of the shaft and the bearing can be fixed to the rotatable hub. In the first embodiment, the bearing is fixed to the stator assembly. In the sixth embodiment, the shaft is fixed to the stator assembly. This is preferably done by molding the body with the stator.

The sixth embodiment is similar to the first embodiment except that the shaft is included in the mold including the stator or that the shaft can be attached to the main body 514 later. Manufactured. This embodiment has the advantages discussed above in connection with the first embodiment. Seventh Embodiment Referring to FIG. 11, a spindle motor 61 is shown in FIG.
A seventh embodiment is shown. This embodiment includes components similar to those of the above-described embodiment, particularly, the first embodiment. Monolithic body 614 is formed using an encapsulation method. The main difference between this embodiment and the first embodiment is that the bearing 618 is significantly larger than the bearing 18 of the first embodiment and is spaced from the shaft 616. This separation is provided by using an upper insert 670 and a lower insert 672 substantially enclosed by a body 614 (see FIG. 12). These inserts
It is preferably annular in shape and acts as an extension of shaft 616. The upper insert 670 and the lower insert 672
It is preferably made of aluminum. The upper insert 670 and the lower insert 672 include a bearing 618 and a shaft 616.
Is positioned between Next, the bearing is attached with an adhesive. In this embodiment, the shaft 616 is secured to the body 614, partially by securing to the insert. The shaft extends from the base 622 so that it can be secured to the base of the hard disk drive. The seventh embodiment is manufactured and used in the same manner as the first embodiment. This embodiment has the advantages discussed above in connection with the first embodiment. An additional advantage of this embodiment is that oversized bearings (bearings with an outer diameter of 13 mm or more) can be used. These large bearings generally have a long life and can operate at higher speeds for extended periods of time. These large bearings dissipate heat more effectively from the bearing surface.

Another great advantage of this embodiment is that the stem from the lower bearing is located in the lower section of the hub. This configuration greatly improves rigidity and reduces disk runout during rotation. This also gives
Higher density data tracks can be used. Inserts 670 and 672 are also thermally conductive to provide rigidity and dissipate heat.

Another advantage is that the manufacturing process for manufacturing the hub shown in this embodiment is very simple and inexpensive. The hub is made of steel instead of aluminum, which eliminates the need for a separate flux return ring. Essentially, the magnet 628
The side wall of the hub on which is mounted acts as a magnetic flux return ring.

In a less preferred variation of the embodiment of FIG. 11, instead of using the lower insert 672, an oversized lower bearing 618 can be supported by providing a large diameter body 614 in place. in this case,
The body acts as an extension of the shaft. In another aspect, a shaft can be formed having a large flange at one end to support an oversized bearing.
In that case, the stator core stack can be placed on the rest of the shaft, an insert similar to the upper insert 670 is secured to the top of the shaft, and the entire structure is placed in a mold to encapsulate the stator and shaft. Eighth Embodiment FIG. 13 shows an eighth embodiment of the spindle motor. This embodiment, called a pancake motor, includes a monolithic body 714 formed by encapsulation. The monolithic body substantially encloses the circuit board 721. On the circuit board are placed copper traces (not shown) which serve as conductors for forming a plurality of magnetic fields. However, this type of stator does not use a steel core. One IC chip controls the current through these copper traces. A magnetic field is generated by passing a current through the trace. This magnetic field rotates the permanent magnet 728 in cooperation with the magnetic field of the permanent magnet 728 attached to the disk support member 712, thereby causing the disk support member 71 to rotate.
Rotate 2. This embodiment has the advantages discussed above in connection with the first embodiment. The circuit board is preferably
It is a multi-level circuit board. Ninth Embodiment A ninth embodiment of the spindle motor 810 is shown in FIG.
This embodiment is somewhat similar to the first embodiment. Monolithic body 814 is formed using an encapsulation method. The main difference between this embodiment and the first embodiment is that the magnet 828 is not fixed to the hub 812 in the sixth embodiment. Instead, the magnet 828 is
Located around the perimeter 16 and are press-fit, glued or welded and extend substantially along the length of the shaft. Further, in this embodiment, the stator 82
0 includes multiple laminates. Further, body 814 is monolithic and includes an upper support portion 842 and a lower support portion 844, each of which supports an upper bearing 846.
And the lower bearing 848. Further, a shaft 816 is attached to the hub 812.

In this embodiment, the shaft 816 acts as a magnetic flux return for the magnet 828. Although not shown, it is clear that the invention is applicable to other embodiments of high speed motors. When the stator is energized, this causes the permanent magnet and shaft to rotate, thereby causing the hub to rotate. In this embodiment, the magnet is connected to the hub by fixing it to a shaft fixed to the hub. Tenth Embodiment FIG. 17 partially shows a tenth embodiment which is another pancake motor and is a modification of the eighth embodiment. This embodiment uses a conductor made of copper wire shaped in the form of a coil 922 placed on a circuit board 921 instead of a copper trace. A magnet 928 is fixed to the bottom of the hub 912, but is shown in exploded form for ease of illustration. The circuit board is encapsulated using a thermoplastic material to form the body 914. A bearing (not shown) can be secured to body 914. Eleventh Embodiment An eleventh embodiment of the motor 1010 of the present invention uses a stator and a shaft connected to each other by a phase changing material as shown in FIG. The phase change material encapsulating the windings 1022 and the rest of the stator 1020 also encapsulates the central portion of the shaft 1016. The bearing 1018 is then attached to the exposed shaft top. The lower part of the shaft extends below the stator so that it can be mounted on the base of the hard disk drive. In this case, the shaft is
0 is used as a mounting structure to hold the hard disk drive in the hard disk drive housing. Hub 1012 includes magnet 1028. One of the advantages of this embodiment is that the phase change material allows the alignment between the shaft 1016 and the stator 1020 to be fixed, eliminating the need to glue the shaft in place. Twelfth Embodiment A twelfth embodiment of the present invention is a hard disk drive 1102 shown in FIGS. The motor of the above embodiment was designed to be manufactured and mounted separately from the base or other housing components of the hard disk drive. In this embodiment, the base 1134 of the hard disk drive is formed as part of an assembly, which includes the stator 112
0 is further enclosed.

The winding 1122 and the shaft 1116 (FIG. 1)
9) is preferably included in the base assembly 1134 (see FIG. 20) when the main body made of the phase changing material is formed by injection molding or the like.
Of course, the shaft 1116 can be added to the base assembly later. Preferably, the body made of a phase change material is a monolithic body made of a thermoplastic material.
The base assembly preferably further includes a second shaft 1126 supported by a body made of a phase changing material. This second shaft 1126 is used to operably support the read / write head 1124 in proximity to one or more disks 1114 supported on the hub 1112. The magnet 11 is attached to the hub 1112.
128 are coupled and arranged to operate in proximity to the stator 1120 when the hub is rotatably supported on the shaft 1116 by bearings 1118. The hard disk drive 1102 is
Preferably, other components such as a circuit board 1130, a winding, and the like are included. These components are those commonly used in hard disk drives and will not be described further. Of course, a cover 1132 is preferably included and is attached to the bearing assembly in a conventional manner. The cover and bearing assembly cooperate to form a housing for the hard disk drive 1102.

One advantage of this embodiment of the present invention is that the motor is built directly into the base assembly, reducing the number of parts. Further, other components of the hard disk drive can be aligned with the motor and the disks supported on the motor. The present invention further relates to a method for developing a high-speed motor. In the illustrated embodiment, the high speed motor includes a stator having a conductor, the stator being substantially encapsulated in a body made of a phase changing material. High speed motors can be developed using this basic design concept and can be quickly optimized for various applications. Further, if the motor includes an insert, the development process includes another degree of freedom in design. There are several basic design parameters that can be varied when developing a motor according to the present invention. These parameters include a) the composition (and properties) of the phase change material, b) the shape of the body made of the phase change material, c) the use and dimensions and stiffness of the insert, d) the magnetic design of the motor (winding, E) the shape, size, and shape of the hub (and any disk used in the hub if the motor is for a hard disk drive).

In the first embodiment in which the motor is developed for a hard disk drive, the development method includes the following steps. A) providing a stator substantially encapsulated within a body of a first phase change material having a number of conductors that generate a plurality of magnetic fields when current is passed;
b) assembling the stator with bearings, shafts, hubs, and disks to form a disk drive;
c) energizing the stator, rotating the hub and disk to generate vibration, and measuring the frequency of this vibration;
d) a step of designing a second phase change material that attenuates the vibration generated by the activation of the stator in step c); and e) repeating steps a) to c), replacing the first phase change material with the second phase change material. Including using the modifying material. Determining at least one of the flexural modulus, elongation, and surface hardness properties by a first
Adjust between the phase change material and the second phase change material to optimize vibration damping. The phase change material is preferably a thermoplastic. An advantage of this method of developing high speed motors is that the properties of the plastics described above can be adjusted to the vibration damping needs of various types and configurations of motors. When the vibration is reduced, the performance of the motor is improved, and the generation of audible noise can be suppressed.

The shape of the body can be varied to reduce harmonic oscillations and thus vibrations. In this embodiment, the method comprises: a) a stator substantially encapsulated in a body of phase change material having a first configuration, comprising a number of conductors that generate a plurality of magnetic fields when current is passed. Providing, b) assembling bearings, shafts, hubs, and disks on the stator to form a disk drive; c) energizing the stator, rotating the hub and disks to generate vibrations, and D) changing the shape of the phase change material to the second form, repeating steps a) to c), and replacing the phase change material having the first form with the phase change material having the second form . In this embodiment, the configuration of the body of phase change material is adjusted to optimize vibration damping. If the body has a bore, wall thickness, and flange as shown in FIGS. 5, 7, and 8, the length, wall thickness, and flange width of the bore may be different from the first and second features. These are design parameters that can be changed between. Of course, other dimensions of the body component can be used. In this aspect of the invention, altering the shape of the phase altering material includes adding elements such as flanges and grooves, or possibly employing a relatively different overall shape.

If the stator assembly is designed so that the phase change material encapsulates the conductor, metal inserts can be incorporated into the stator assembly, and the shape, size, or rigidity of these inserts can be as desired. It can be selected and / or designed to dampen unwanted harmonic vibrations.
In this embodiment, the method of developing a high speed motor comprises: a) providing a stator substantially encapsulated within a body of phase change material, comprising a number of conductors that generate a plurality of magnetic fields when a current is passed. B) assembling the stator with the bearing, shaft, hub and disk to form a disk drive; c) energizing the stator and rotating the hub and disk to generate vibrations, Measuring the frequency of a. D) providing a metal insert substantially encapsulated within the body of the phase change material;
e) repeating steps a) to c) and adjusting at least one of the stiffness and thickness of the insert to optimize vibration damping. Another embodiment of the present invention for developing high speed motors includes: a) a stator substantially encapsulated within a body of phase changing material, comprising a number of conductors that generate a plurality of magnetic fields when current is passed. Providing the process,
b) assembling the stator with bearings, shafts, hubs, and disks to form a disk drive;
c) energizing the stator, rotating the hub and disk to generate vibration, and measuring the frequency of this vibration;
d) the hub, the disk, the vibration of the harmonic oscillation frequency of the disk drive is attenuated by the phase changing material;
Or changing both of them.

Of course, a combination of these four methods could also be used, changing both the characteristics of the phase change material and adding an insert to the body. Further, if the motor is to be used in a device other than a hard disk drive, gears, pulleys, rims, fan blades, or other components to be rotated by the motor must be removed from the hub and drive prior to energizing the motor. It can be developed in the same way, except that it can be mounted instead of a disc.

The present invention further relates to another method for developing a high speed motor. As with the other methods, also in this method, the high speed motor includes a body of phase change material substantially enclosing the stator. High speed motors include one or more, typically multiple, solid components used near or within the body, such as bearings and inserts. Further, solid components such as a disk support member and a hard disk base are provided near the main body. The method of developing high speed motors is to design the phase change material to have a predetermined coefficient of linear thermal expansion (CLTE) such that the phase change material contracts and expands at about the same rate as one or more solid components. The step of performing For example, the preferred phase change material CLTE is 70% of the stator core CLTE.
% To 130%. Phase change material C
LTE, when the body is in contact with a different material,
It must be between the maximum and minimum values of CLTE for solid parts. In addition, the CLTE of the body and the solid parts must be compatible over the temperature range of the operating motor. The advantage of this method is that the tolerance between the body and the solid part can be more precise because the CLTE of the body closely matches the CLTE of the solid part.

[0069] In many cases, the solid parts are metals, most often steel, copper, and aluminum. The solid component may include ceramic. Almost all motors have metal bearings. Thus, a common element of this aspect of the invention is that the motor is developed by designing the phase change material to have approximately the same CLTE as the metal used to manufacture the bearing.

[0070] Many thermoplastic materials have a relatively high CLTE.
high. Some thermoplastic materials have low CLTE at low temperatures.
Similar to the genus CLTE. However, at high temperatures,
Incompatible metal and CLTE. Of preferred thermoplastic materials
CLTE should be over the expected operating temperature of the motor, preferably
-17.8 ° C to 121.1 ° C (0 ° F to 250 °
3.6 × 10 over the range of F)^-Five/ ° C (2 × 10^-Fivei
n / in /⁰F), and more preferably 2.7 × 10^-Five
/ ° C (1.5 × 10^-Fivein / in /⁰F). Even better
Preferably, CLTE is between -17.8 ° C and 121.1 ° C.
(0⁰F to 250 ⁰About 1.44 × 10 over the range of F)
^-Five/ ° C (about 0.8 × 10^-Fivein / in /⁰F) to about 2.
16 × 10^-Five/ ° C (about 1.2 × 10^-Fivein / in /⁰F)
It is. (The CLTE of the measured material is determined by the measurement direction.
That is, the relevant CLTE for the purpose of defining the invention
Is CLTE in the direction in which CLTE is minimized. )
CLTE of general solid parts used in motors is as follows
It is as follows.

23 ° C. 250 ⁰ F Steel 0.9 (0.5) 1.44 (0.8) Aluminum 1.44 (0.8) 2.52 (1.4) Ceramic 0.3 (0.54) ) 0.4 (0.72) Here, the unit is × 10 ⁻⁵ / ° C. (× 10 ⁻⁵ in / in /
⁰ F).

Of course, if the motor is designed to use two or more different solids, such as steel and aluminum components, then the phase change material C
The LTE is preferably an intermediate CLTE between the maximum CLTE and the minimum CLTE of different solids, and is 1.17 at room temperature.
× 10 ^-5 is ^{/℃(0.65×10 -5 in / in / 0 F} ), 250 0 F at 1.98 × 10 ^-5 /℃(1.1×10 ^-5
in / in / is ⁰ F).

One preferred thermoplastic material, namely Conduit
The OTT-212-11 is formed in a thermoplastic body and
The coefficient of linear thermal expansion:
Test. In the x-axis direction in the range of -30 ° C to 30 ° C
Has a CLTE of 1.962 × 10^-Five/ ° C (1.09 × 10
^-Fivein / in /⁰F), in both the y-axis direction and the z-axis direction.
CLTE in direction is 2.268 × 10^-Five/ ° C (1.26
× 10^-Fivein / in / ⁰F), from 100 ° C. to 240
CLTE in the x-axis direction in the range of ° C. is 2.304 × 10
^-Five/ ° C (1.28 × 10^-Fivein / in /⁰F) and y
CLTE in both axial and z-axis directions is 5.688
× 10^-Five/ ° C (3.16 x 10^-Fivein / in /⁰F)
You. (Thus, the relevant CL for the purpose of defining the invention
TE is 1.962 × 10^-Five/ ° C (1.09 × 10^-Fivei
n / in / ° F) and 2.304 x 10^-Five/ ° C (1.2
8 × 10^-Fivein / in /⁰F). ) Another similar material
Conduit PDX-0-988 is from -30 ° C
CLTE in the x-axis direction in the range of 30 ° C. is 1.98 × 1
0^-Five/ ° C (1.1 × 10^-Fivein / in /⁰F) and y
CLTE of 2.628 in both the axial and z-axis directions
× 10^-Five/ ° C (1.46 x 10^-Fivein / in /⁰F)
And CL in the x-axis direction in the range of 100 ° C. to 240 ° C.
TE is 2.088 × 10^-Five/ ° C (1.16 × 10^-Fivein
/ In /⁰F), in both the y-axis direction and the z-axis direction.
CLTE is 6.12 × 10^-Five/ ° C (3.4 × 10^-Fivei
n / in /⁰F). For control, PBS-type polymer
(Fortron 4665) is similarly tested. -30 ° C
CLTE in the range of ~ 30 ° C is low (in the x-axis direction
1.89 × 10^-Five/ ° C (1.05 × 10^-Fivein / in /
⁰F), and 2.3 in both the y-axis direction and the z-axis direction.
94 × 10^-Five/ ° C (1.33 × 10^-Fivein / in /⁰F)
But C in the range of 100 ° C. to 240 ° C.
LTE is much higher (3.492 × 10 in the x-axis direction)^-Five
/ ° C (1.94 × 10^-Fivein / in /⁰F) and the y-axis
7.506 × 10 in both the direction and the z-axis direction^-Five/ ℃
(4.17 × 10^-Fivein / in /⁰F)).

The preferred phase change material is the desired CLTE
In addition to having high thermal conductivity. The thermal conductivity of the preferred thermoplastic is at room temperature (23 ° C.) at ASTM 0
149 measured at least 0.7 watts /
(Meters / ° K).

The above-mentioned CL in which the stator is partially enclosed
A stator assembly having a body made of a phase change material having TE or thermal conductivity is novel per se and constitutes another feature of the present invention. Once encapsulated, the stator assembly preferably contains 0.328 μm or larger particles, at which the part will generate during testing, is 0.0283 μm.
You can meet industry standards for the release of the manufacturer of the particles of the disk drive that require 168 m ³ is (1 cubic foot) of 10 or less per air. This is mainly due to the lack of machined mounting plates and the other particle sources (steel laminates, winding wires, and wire / terminal connections) being hermetically sealed.

Furthermore, the encapsulation ensures that the varnish used to insulate the wires within the windings and the epoxy used to prevent oxidation of the steel laminate are hermetically sealed within the stator assembly. Gas generation is reduced. Furthermore, because of the small number of parts, less adhesive is needed to hold the parts together. The reduced generation of such gases reduces the amount of material affecting the magnetic media or head used in the disk drive.

Another feature of the present invention uses the above-described basic motor with vibration damping to form a hard disk drive. The attenuated vibration may be an audible frequency vibration or another frequency vibration. When the vibration at the audible frequency is attenuated, a disk drive with less audible noise is provided. As mentioned above, the data that can be recorded on a hard drive depends on how narrow the data track spacing is. Because of the reduced vibrations of the features of the present invention, the spacing of the data tracks during operation of the hard drive can be further reduced.

The vibration in question is generally generated by harmonic oscillation. The phase changing material can be selected to attenuate the harmonic oscillation frequency oscillations generated by the motor. Many of these oscillations are determined by the shape of the windings or other conductors.
Thus, in one aspect, the invention provides a motor having multiple conductors that generate multiple magnetic fields when current is passed;
A motor and disk assembly including a stator having a monolithic body of phase change material that substantially encapsulates these conductors. In this regard, the phase change material is:
It has a vibration damping effect of reducing harmonic vibration oscillation of the motor / disk assembly.

The phase change material has a number of properties that can be varied to attenuate various harmonic frequencies with the phase change material. This includes adding or changing the amount of glass, Kevlar, carbon or other fiber in the material, adding or changing the amount of ceramic filler in the material, and changing the type of material to polyphenyl. How to change from sulfide to nylon or other liquid crystal polymer or aromatic polyester and add or graft an elastomer to the polymer used as the phase change material, and use a different molecular weight if the phase change material is a polymer How to include. Changes that affect the bending stiffness, elongation properties, or surface hardness properties of a phase changing material also affect its vibration damping properties.

One method for determining the effectiveness of vibration damping, and thus selecting the appropriate material, is to form the motor features using various phase changing materials and then obtain the vibration damping obtained with each material. Is to measure Vibration damping can be measured with a capacitive probe or a laser Doppler vibrometer. In the range of 200 Hz to 2000 Hz, and preferably in the range of 300 Hz to 2000 Hz, a disk drive using the high speed motor of the present invention preferably reduces the amplitude of harmonic oscillations by at least 5 dB, and more preferably by at least 10 dB. . In the audible range, i.e. between 20 Hz and 15000 Hz, the attenuation is preferably at least 2 dB, more preferably at least 5 dB, at the harmonic frequency amplitude. These reductions are evaluated based on a comparison with the vibration of the same motor that the stator does not encapsulate.

By reducing the vibration, a unique hard disk drive having a high data density and a method of manufacturing the same can be provided. According to this feature of the present invention, the spindle motor in which the generation of the vibration is suppressed is formed so as to have a characteristic that the vibration is small. The motor includes a stator assembly having a stator substantially encased within a body made of a phase changing material, a rotatable disk support member to which magnets are coupled, a shaft, and a bearing surrounding the shaft, wherein the shaft or the bearing. The shaft is fixed to the stator assembly, and the other of the shaft and the bearing is fixed to the disk support member. The spindle motor is built into the hard disk drive and the magnetic storage medium is placed on a disk support. The feature of the motor that the vibration is small has an advantage that the data track of the magnetic storage medium is narrowed. Preferably, the data tracks are spaced to have at least 10,000 tracks per inch.

The vibration damping force of the phase change material can be used in another aspect of the present invention to improve the shock resistance of a hard disk drive having a high speed drive. In this aspect of the invention, the body of phase change material is shock absorbing and is mounted on the housing of the hard disk drive.
Vibration damping minimizes the energy transferred between the hard disk drive housing and the magnetic storage medium.

One problem encountered with hard disk drives is that, since the various components used to form the motor contain particles, these components must be ultrasonically cleaned before assembly and then Means that the assembly work must be performed in a clean room environment. For example, when manufacturing a stator, it has been found that the steel core pieces and the wires used to form the windings that are stacked together have small particles attached that must be removed. The particles are removed from the laminate before the winding is installed. This is because cleaning the stator after assembly without cleaning the parts requires costly and time consuming cleaning techniques. Thereafter, the varnish adhering to the windings may come off at the time of assembling the motor, or some particles may be generated when the motor pieces hit each other.

One of the features of the present invention is that these particles are eliminated when the stator is encapsulated, and the encapsulation makes the stator assembly robust, so that less expensive ultrasonic cleaning can be used. First, there is no need to clean the stator stack and windings prior to their inclusion. Thereafter, after cleaning and cleaning the stator assembly, it can be used to form a hard disk drive without the need for a clean room environment. Thus, in this aspect, the invention comprises a) forming a stator including a laminated steel core and wire windings; and b) substantially enclosing the stator within a body of phase change material to form a stator assembly. C) ultrasonically cleaning the stator assembly; d) assembling the stator assembly with bearings, shafts and generators to form a spindle motor; and e) assembling the spindle motor with a hard disk drive. And

One unique feature of the present invention is that different stators can be encapsulated with the same molding tool.
For example, stators that differ in one or more of properties such as the number of turns of the wire, the number of magnetic poles, the diameter, and / or the thickness can all be mounted in the same molding tool. As such, a first type of stator can be encapsulated by adding a thermoplastic or other phase changing material to a molding tool by injection molding or other methods, and then the first type of stator, bearing, and shaft can be encapsulated. Used to form a first type of motor. A second type of stator can then be encapsulated and the same or different bearings and shafts are used to form a second type of motor. This not only reduces the number of molding tools required, but also ultimately equalizes the size and shape of the stator assembly. This is because the dimensions of the main body made of the phase change material are the same. As a result, the motor and other components of the drive, such as the housing, can be constant between different disk drives.

In addition to the embodiments discussed above, similar structures, manufacturing methods, and development methods for high speed motors can be used with high speed motors used in other types of applications. For example, these high speed motors can be used in CD and DVD players, video cassette systems, digital cameras, and robotic servomotors.

Some of the advantages of the preferred embodiment of the present invention are briefly described below. In particular, reducing vibration by encapsulating the stator with a thermoplastic material designed to reduce vibration for a particular motor configuration,
It is advantageous in many respects. First, hard disks can be designed to store data more densely. Preferably,
Hard disk drive is 2.54 cm (1 inch)
Use data tracks that are compact enough to ensure access to 10,000 data tracks per track.
Reducing vibration makes the use of hydrodynamic bearings practical.

Further, when the vibration is reduced, the friction and wear at the bearing are reduced, so that the heat generated by the motor is reduced, the life of the motor and the bearing is prolonged, and a larger power can be obtained. By using the features of the present invention, it is possible to form a motor that can rotate at a speed of 5000 rpm or more in a hard disk drive. Preferred motors can rotate at 7500 rpm or more, and in a more preferred embodiment 10,000 rpm
pm or higher.

The present invention can be used in a motor having a laminated structure and a wire winding. Further, a motor or structure using a circuit board configuration can be used with a motor provided on a circuit board. There are many ways to improve thermal conductivity.
First, the phase change material itself provides such heat dissipation. Second, additives that increase thermal conductivity can be added to the phase change material. Third, a thermally conductive insert can be added to the motor. Fourth, the body of phase change material can act as a heat path by contacting a number of components of the motor and / or disk drive, and the motor and / or other components of the disk drive can be connected to heat sinks. Can act as Such improved thermal conductivity extends the life of the motor electronics and bearing components, provides a higher power device, increases efficiency, and lowers the current drawn. If the motor is battery operated, battery life is extended.

The present invention allows oversized bearings to be used in practice, thereby reducing wear due to vibration, lowering temperatures, and extending bearing life.
The unique motor design makes the manufacturing process unique.
There is no need to wash the laminate and winding separately, and once the stator assembly is encapsulated, no contaminants are generated. Furthermore, if the insert is encapsulated, machining provides the correct dimensions and a single cleaning step can be used after every assembly step. Apart from the present invention, it is not practical to perform this type of machining on assembled parts. This is because there is virtually no way to clean the entire assembly after such machining. Thus, hard disk drives can be formed without the need for strict "clean room" conditions. Only one ultrasonic cleaning step is required. Cellular
Manufacturing technology can be used. The motor can be manufactured anywhere and then cleaned just before assembly with the hard disk drive. There is no need for costly packaging to keep the stator assembly clean.
In addition, the robustness of the stator assembly allows transportation at low cost.

A hard disk drive incorporating a preferred motor has high reliability because of its low particle level and low gas generation. The hard disk drive has improved impact resistance when the drive is dropped. The heads used in hard disk drives are electrically isolated from the motor conductors without having to use a separate insulator. Preferred motors and disk drives are
Works quietly.

By using the sealed stator, the terminal connector can be integrated with the main body.
In general, the motor is relatively easy to assemble and includes a small number of parts. As mentioned above,
Since the phase change material can be designed to have substantially the same CLTE as the other components of the motor, the stacking of tolerances is reduced. By adapting CLTE, good environmental conditions are obtained. Otherwise, the plastic will be microcracked and the encapsulated components will be corroded by fluids such as moisture.

There are a number of cost advantages associated with the features of the present invention. Cost advantages are obtained by having a small number of parts. Die cast aluminum base 2 (Fig. 1
And one body made of phase change material instead of various insulators. The cost of the manufacturing process is low. The tool life used for injection molding of thermoplastics is longer than the tool used for die casting.
Plastic molding tools produce less parts per hour than aluminum die cast tools, which reduces costs. Furthermore, costs are reduced because plastic parts require less post-molding machining than aluminum parts.

Further, there are advantages associated with development time and cost for new motor configurations. Design can be done quickly. First, because of the small number of parts, the number of parts that must be designed for each new motor is small. Second, the number of required tools is small due to the small number of parts required. Third, the injection molding tool is modular. This allows for easy customization of the tool without having to redesign the entire tool. In many cases, one tool can be used repeatedly for many product designs. For example, a plastic molding tool can be used for a number of windings.

The embodiments of the present invention disclosed herein are:
Although this is the currently preferred embodiment,
Various modifications and changes can be made without departing from the spirit and scope of the invention. The scope of the invention is set forth in the appended claims, and all changes within the meaning and range of equivalency are included in the scope of the claims.

[Brief description of the drawings]

FIG. 1 is an exploded partial cross-sectional perspective view of a conventional high-speed motor.

FIG. 2 is a perspective view of a stator used in the first embodiment of the present invention.

FIG. 3 is an exploded partial cross-sectional perspective view of the high-speed motor according to the first embodiment of the present invention.

FIG. 4 is a sectional view of the high-speed motor of FIG. 3;

FIG. 5 is an exploded partial cross-sectional perspective view of a high-speed motor according to a second embodiment of the present invention.

FIG. 6 is a sectional view of the high-speed motor shown in FIG.

FIG. 7 is an exploded partial cross-sectional perspective view of a high-speed motor according to a third embodiment of the present invention.

FIG. 8 is an exploded partial sectional perspective view of a high-speed motor according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view of a high-speed motor according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view of a high-speed motor according to a sixth embodiment of the present invention.

FIG. 11 is a sectional view of a high-speed motor according to a seventh embodiment of the present invention.

FIG. 12 is a perspective view of an insert used in the high-speed motor of FIG. 11;

FIG. 13 is a sectional view of a high-speed motor according to an eighth embodiment of the present invention.

FIG. 14 is an exploded partial cross-sectional perspective view of a high-speed motor according to a ninth embodiment of the present invention.

FIG. 15 is a view of a mold used for manufacturing the encapsulated stator of FIG. 3;

16 is a view of the mold of FIG. 15 in a closed position.

FIG. 17 is an exploded partial cross-sectional view of components used in a pancake motor according to a tenth embodiment of the present invention.

FIG. 18 is a sectional view of a high-speed motor according to an eleventh embodiment of the present invention.

FIG. 19 is a perspective view of a stator and a shaft used in a twelfth embodiment of the present invention.

FIG. 20 is an exploded partial sectional view of the hard disk drive of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Spindle motor 11 Steel laminated body 12 Hub 13 Stator assembly 14 Main body 15 Winding 16 Shaft 17 Magnetic inductive core 18 Bearing 20 Stator 21 Magnetic pole

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H02K 7/08 H02K 7/08 A 11/00 15/02 D 15/02 15/14 A 15/14 21/16 M 21/16 29/00 Z 29/00 11/00 X

Claims (135)

[Claims] 1. A high-speed spindle motor, wherein the high-speed spindle motor comprises: a) a stator assembly, the stator assembly comprising: i) a stator having a plurality of conductors for generating a plurality of magnetic fields when energized; ii) A stator assembly, comprising: a body of phase change material substantially surrounding the stator; b) a rotatable hub, actuated to the hub proximate to the stator. C) a shaft, d) bearings around the shaft, and e) one of the shaft and the bearing is the stator. The other of the shaft and the bearing is fixed to the assembly and is fixed to the rotatable hub. Has a high speed spindle motor. 2. The high-speed spindle motor according to claim 1, wherein the main body made of the phase changing material is a monolithic main body. 3. The high speed spindle motor according to claim 1, wherein said bearing is fixed to said stator assembly. 4. The high-speed spindle motor according to claim 3, wherein said bearing is fixed to said main body. 5. The high-speed spindle motor according to claim 1, wherein said shaft is fixed to said hub. 6. The magnet is fixed to the hub,
The high-speed spindle motor according to claim 4. 7. The high speed spindle motor according to claim 5, wherein the magnet is connected to the shaft, and the shaft is fixed to the hub. 8. The high speed spindle motor according to claim 1, wherein said shaft is fixed to said stator assembly. 9. The high-speed spindle motor according to claim 8, wherein the stator further includes a core and a conductor that generates a magnetic field when a current is passed. 10. The high speed spindle motor according to claim 9, wherein said core includes a steel laminate. 11. The high-speed spindle motor according to claim 9, wherein the core has a plurality of magnetic poles, and the conductor includes a winding wound around the magnetic pole. 12. The high speed spindle motor according to claim 1, wherein the conductor includes a plurality of windings. 13. The high-speed spindle motor according to claim 12, wherein the spindle motor has a pancake motor and a conductor including a winding attached to a circuit board. 14. The high speed spindle motor according to claim 1, wherein the conductor includes an electric trace provided on a circuit board. 15. The high speed spindle motor according to claim 1, wherein the hub includes a hard disk drive support member. 16. The high speed spindle motor according to claim 1, wherein the motor can operate at 5000 rpm or more. 17. The motor may have at least 7500 rpm
2. The high speed spindle motor according to claim 1, operable at m. 18. The motor may have at least 10,000 r
2. The high speed spindle motor according to claim 1, operable at pm. 19. The high-speed spindle motor according to claim 1, wherein the magnet connected to the hub is a permanent magnet. 20. The high-speed spindle motor according to claim 1, wherein the bearing includes an upper bearing and a lower bearing. 21. The high speed spindle motor according to claim 20, wherein the main body surrounds the upper bearing and the lower bearing. 22. The high speed spindle motor according to claim 1, wherein the stator assembly further has a terminal for connecting the conductor to a power supply external to the motor. 23. The high speed spindle motor according to claim 22, wherein the terminal is partially enclosed in the main body. 24. The high speed spindle motor according to claim 1, wherein a hole for attaching the high speed motor to a hard disk drive is formed in the main body. 25. The high-speed spindle motor according to claim 1, wherein the magnet is disposed concentrically around the stator. 26. The high speed spindle motor according to claim 1, wherein said bearing comprises a ball bearing. 27. The high-speed spindle motor according to claim 26, wherein the bearing includes an oversized bearing having an outer diameter of 13 mm or more. 28. The high speed spindle motor according to claim 1, wherein said bearing is a hydrodynamic bearing. 29. The high speed spindle motor according to claim 1, wherein the stator concentrically surrounds the magnet. 30. The high-speed spindle motor according to claim 1, wherein the phase change material includes a material that changes from a liquid to a solid by a change in temperature. 31. The high speed spindle motor according to claim 30, wherein said phase change material comprises a thermoplastic material. 32. The high speed spindle motor according to claim 30, wherein the phase change material includes a thermosetting material. 33. The high speed spindle motor according to claim 30, wherein the phase change material includes a material that changes from a liquid to a solid by a chemical reaction. 34. The phase change material comprises an epoxy.
A high speed spindle motor according to claim 33. 35. The high speed spindle motor according to claim 1, wherein the stator and the magnet are substantially in the same plane. 36. The high speed spindle motor according to claim 1, wherein a solid insert is substantially enclosed within said body. 37. The high speed spindle motor according to claim 36, wherein said insert provides structural rigidity to said stator assembly. 38. The high speed spindle motor according to claim 36, wherein the insert enhances heat transfer from the bearing and the stator. 39. The magnetic bearing according to claim 1, wherein a first portion of the magnetic bearing is substantially encapsulated within the body, and a second opposite portion of the magnetic bearing is attached to the hub.
2. A high-speed spindle motor according to claim 1. 40. The high speed of claim 39, wherein the body is machined to provide a precise tolerance between the first and second portions of the magnetic bearing. Spindle motor. 41. The high-speed spindle motor according to claim 36, wherein the insert enhances vibration damping of the motor. 42. The high speed spindle motor according to claim 36, wherein the insert improves audible noise attenuation. 43. The high speed spindle motor according to claim 36, wherein the shaft is fixed to a main body, and the insert is positioned between the shaft and the bearing. 44. The high-speed spindle motor according to claim 43, wherein the bearing includes an oversized bearing having an outer diameter of 13 mm or more. 45. The high speed spindle motor according to claim 1, wherein a reinforcing magnet is substantially enclosed within said body. 46. The high speed spindle motor according to claim 1, wherein the main body is formed by injection molding a thermoplastic material. 47. The high speed spindle motor according to claim 46, wherein the body made of a thermoplastic material is monolithic. 48. The high speed spindle motor according to claim 1, wherein said phase change material comprises ceramic particles. 49. The phase change material, -17.8 ° C. to 121.1 ° C. (0 ° F to 250 ° F) linear thermal expansion coefficient in the range ^{of, 3.6 × 10? 5 / ℃} (2 × 10 ^{? 5} in
2. The high-speed spindle motor according to claim 1, wherein the ratio is equal to or less than / in / ΔF). 50. The phase change material has a linear thermal expansion coefficient in a range of -17.8 ° C. to 121.1 ° C. (0 ° F. to 250 ° F.) of 2.7 × 10 ⁻⁵ / ° C. (1. .5 × 10 ^-5
2. The high-speed spindle motor according to claim 1, wherein the speed is not more than (in / in / ° F). 51. The phase change material has a linear thermal expansion coefficient of 1.44 × 10 ⁻⁵ / ° C. (0 ° F. to 250 ° F.) from −17.8 ° C. to 121.1 ° C. (0 ° F. to 250 ° F.). 8 × 10 ^-5 in /
in / ° F) to 2.16 × 10 ^-5 / ° C (1.2 × 10
^-5 in / in / ° F). 52. The bearing is made of steel, the hub is made of aluminum, and a linear thermal expansion coefficient of the phase change material is between a linear thermal expansion coefficient of steel and a linear thermal expansion coefficient of aluminum. The high-speed spindle motor according to claim 1. 53. The thermal conductivity of the phase change material is 23.
The high speed spindle motor according to claim 1, wherein the high speed spindle motor is at least 0.7 Watt / (meter · ゜ K) at ° C. 54. The phase change material is polyphenyl
2. The high speed spindle motor according to claim 1, comprising sulfide. 55. The dielectric strength of the phase change material is at least 250 volts / mil (9842.52 v / mm).
The high-speed spindle motor according to claim 1, wherein 56. The thermal conductivity of the phase change material is 23
56. The high speed spindle motor according to claim 55, wherein the high speed spindle motor is at least 0.7 watts / (meter · K) at ° C. 57. A high speed spindle motor comprising: a) a stator substantially encapsulated in a thermoplastic body having a cylindrical hole; b) a bearing press-fit into said hole; c) rotation by said bearing. A high speed spindle motor comprising: a freely supported shaft; and d) a hub coupled to the magnet and fixed to said shaft. 58. A high speed spindle motor for a disk drive, the high speed spindle motor comprising: a) a shaft; b) a disk support member having a permanent magnet and mounted on the shaft; c) A) a bearing surrounding the shaft; d) a stator; e) a body formed to be monolithic, the body substantially enclosing the stator, and the body comprising the shaft and the disk. A high speed spindle motor comprising: the body configured to align a support member and a bearing with each other. 59. The high speed motor according to claim 58, wherein said body surrounds said bearing. 60. The high speed motor according to claim 58, wherein said bearings include an upper bearing and a lower bearing. 61. The high speed motor according to claim 60, wherein said body substantially surrounds said upper bearing and said lower bearing. 62. The high speed motor according to claim 58, wherein said shaft is fixed to said body. 63. The high speed motor according to claim 58, wherein said shaft is free to rotate with respect to said body. 64. The high-speed motor according to claim 58, wherein attachment means for attaching the high-speed motor to a hard disk drive is formed. 65. The high speed motor according to claim 58, wherein an insert is substantially encapsulated within said body. 66. The high speed motor according to claim 58, wherein said permanent magnets are arranged concentrically around said stator. 67. The high speed motor according to claim 58, wherein said stator concentrically surrounds said permanent magnet. 68. The high speed motor according to claim 58, wherein a second magnet is substantially enclosed within said body. 69. The high-speed motor according to claim 58, wherein the second magnet is a reinforcing magnet. 70. The high speed motor according to claim 58, wherein said second magnet is a component of a magnetic bearing. 71. A high speed spindle motor for a disk drive, comprising: a) a shaft; b) a disk support member mounted on the shaft; c) a bearing disposed about the shaft; and d) a stator. E) a monolithically formed body, said body substantially enclosing said stator, said body surrounding said bearing and said shaft, and said monolithically formed body; High speed spindle motor. 72. The high speed motor according to claim 71, wherein said bearings include an upper bearing and a lower bearing. 73. The high speed motor according to claim 71, wherein said body concentrically surrounds said upper bearing and said lower bearing. 74. The high speed motor according to claim 71, wherein a solid insert is substantially enclosed within said body. 75. The high speed motor according to claim 71, wherein a reinforcing magnet is substantially encapsulated within said body. 76. The high speed motor according to claim 71, wherein magnetic bearing components are substantially encapsulated within said body. 77. A high speed motor for a disk drive, comprising: a) a shaft; b) a disk support member positioned concentrically with respect to said shaft; and c) between said disk support member and said shaft. D) a stator, e) a monolithically formed body, said body substantially enclosing said stator, said monolithically formed body surrounding a periphery of said bearing. A monolithically formed body, wherein the monolithically formed body is configured to substantially surround the shaft; and the monolithically formed body is configured to substantially surround the shaft. 78. A method of manufacturing a high-speed motor for a disk drive, comprising: a) providing a shaft; b) providing a disk support; c) providing a bearing; Providing a stator with multiple conductors that generate a plurality of magnetic fields; e) substantially encapsulating the stator with a phase changing material to form a monolithic body having an interior portion; f. A) disposing the bearing and the shaft in the internal portion; and g) attaching the disk support member to the shaft. 79. The method of claim 78, further comprising: a) providing a magnet; and b) substantially encapsulating the magnet with the phase change material. 80. The method of claim 79, wherein the magnet is first completely encapsulated and the method further comprises machining the phase change material to expose a portion of the magnet. . 81. The magnet as in claim 8, wherein the magnet is a reinforced magnet.
The method according to 0. 82. The method of claim 80, wherein said magnet is a component of a magnetic bearing. 83. The method of claim 78, wherein said interior portion is perforated to the size of said bearing. 84. A method of developing a high speed motor for an apparatus, comprising: a) providing a stator, the stator having a plurality of conductors, wherein the conductors include a plurality of magnetic fields when energized through the conductors. Providing the stator substantially encapsulated within a body made of a first phase change material; and b) coupling the stator with a bearing and a shaft to assemble the apparatus. Assembling with components to be rotated by the motor; c) energizing the stator, rotating the components in such a way that vibrations are generated, and measuring the frequency of the vibrations; d. E) designing a second phase change material for attenuating the vibration generated by the biasing of the stator; and e) repeating the steps a) to c) to perform the first phase change. Replacing the material with the second phase change material, wherein at least one of the flexural modulus, elongation, and surface strength properties of the phase change material is changed between the first and second phase change materials. A method for developing a high-speed motor, comprising: 85. The method of claim 84, wherein said device comprises a hard disk drive and said component to be rotated comprises a hub and one or more disks. 86. A method of developing a high-speed motor for an apparatus, comprising: a) providing a stator having a plurality of conductors, wherein the plurality of conductors generate a plurality of magnetic fields when energized through the plurality of conductors. Said step of substantially enclosing said stator in a body of phase change material having a first configuration; and b) connecting said stator to a bearing, shaft and components to form said apparatus. C) energizing the stator, rotating the components in such a way that vibrations are generated, and measuring the frequency of the vibrations; d) changing the shape of the phase change material 2) and repeating steps a) to c) above, using a phase change material having a second form instead of the phase change material having a first form, wherein the shape is changed to And a step of adjusting to optimize the attenuation of vibrations, the development method of high-speed motors. 87. The method of claim 86, wherein said device comprises a hard disk drive and said rotating component comprises a hub and one or more disks. 88. The first and second configurations have a bore of a predetermined length, a wall of a predetermined thickness, and a flange of a predetermined width, respectively. At least one of the bore length, wall thickness and flange width is different,
89. The method according to claim 86. 89. A method of developing a high speed motor for an apparatus, comprising: a) providing a stator having a plurality of conductors, wherein the plurality of conductors generate a plurality of magnetic fields when energized through the plurality of conductors. Generating, wherein said stator is substantially encapsulated within a body of phase change material; and b) configuring said stator to be rotated by bearings, shafts, and said motor to form said apparatus. C) energizing the stator, rotating the components in such a way that vibrations are generated, and measuring the frequency of the vibrations; and d) measuring the frequency of the phase change material. Including a metal insert substantially encapsulated therein; and e) repeating steps a) through c) to optimize vibration damping to increase the flexural modulus and elongation of the insert. And a step of adjusting at least one of a surface strength and shape, and how to develop high-speed motors. 90. The method of claim 89, wherein the device comprises a hard disk drive and the rotating components comprise a hub and one or more disks. 91. A method of developing a high speed motor for an apparatus, comprising: a) providing a stator having a plurality of conductors, the plurality of conductors generating a plurality of magnetic fields when energized through the plurality of conductors; Said step of substantially enclosing said stator within a body of phase change material; b) assembling said stator with bearings, shafts and rotating components to constitute said apparatus; c. C) energizing the stator, rotating the component such that the component generates vibration, and measuring the frequency of the vibration; and d) vibration of the harmonic oscillation frequency is attenuated by the phase change material. Modifying the magnetic design of the motor so that: 92. The method of claim 91, wherein said device comprises a hard disk drive and said rotating component comprises a hub and one or more disks. 93. A method for developing a high-speed motor for a hard disk drive, comprising: a) providing a stator having a plurality of conductors, wherein the plurality of conductors generate a plurality of magnetic fields when energized through the plurality of conductors. Said step, wherein said stator is substantially encapsulated within a body made of a phase changing material; and b) forming said disk stator into one or more of a bearing, a shaft and a hub to form a disk drive. Assembling with said discs; c) energizing said stator and rotating said hub and said one or more discs in such a way as to generate vibrations and measuring the frequency of said vibrations; D) the hub and the one or more disks so that vibrations of the harmonic oscillation frequency of the disk drive are attenuated by a phase changing material. And a step of changing at least one of the click, how to develop high-speed motors. 94. A method of developing a high speed motor comprising: a) providing a stator substantially encapsulated within a body made of a phase changing material; b) either within or near the body. Providing one or more solid components for use in the motor; and c) providing the phase change material to contract and expand at approximately the same rate as the one or more solid components. Designing a phase change material to have a predetermined coefficient of linear thermal expansion. 95. The method of claim 94, wherein said one or more solid components comprises a metal. 96. The method of claim 94, wherein said one or more solid components comprises a ceramic. 97. The one or more solid parts,
95. The method of claim 94, comprising a metal insert molded into the body. 98. The one or more solid parts,
95. The method of claim 94, comprising a metal bearing. 99. There are a plurality of solid components located either within or near the body, wherein the solid components have different coefficients of linear thermal expansion, and the phase change material comprises a different solid linear thermal expansion. 95. The method of claim 94 having a coefficient of linear thermal expansion intermediate between the maximum and minimum values of the modulus. 100. The different solids include steel and copper,
100. The method of claim 99. 101. The method of claim 99, wherein said different solids include metals and ceramics. 102. A stator assembly comprising: a) a magnetically inductive core; b) a plurality of conductors proximate to the core so as to induce a magnetic field in the core when energized; A body substantially encapsulated and comprising a phase change material having a coefficient of linear thermal expansion substantially equal to the coefficient of linear thermal expansion of the core. 103. The linear thermal expansion coefficient of the phase change material is:
103. The stator assembly according to claim 102, wherein said core has a linear thermal expansion coefficient of 70% to 130%. 104. The thermal conductivity of the phase change material is 2
103. The stator assembly of claim 102, wherein the stator assembly is at least 0.7 watts / meter at 3C. 105. The phase change material has a temperature of −17.8 ° C.
The linear thermal expansion coefficient is 1.44 × 10 ⁻⁵ ° C. (0.8 × 10 ° C.) in the range of 0 ° C. to 121.1 ° C. (0 ° F. to 250 ° F.).
^-5 in / in / ° F) to 2.7 × 10 ^-5 / ° C (1.5
103. The stator assembly according to claim 102, wherein the stator assembly is about ^10-5 in / in / ° F. 106. The stator assembly according to claim 102, further comprising a plurality of terminals for connecting said conductor to a power source, said terminals being partially encapsulated in said body. 107. The method of claim 1, further comprising the step of:
One or more metal inserts, said inserts comprising:
103. The stator assembly of claim 102, wherein the stator assembly provides one or more properties selected from the group consisting of high stiffness, high thermal conductivity, vibration damping properties, and high magnetic effects. 108. A stator assembly, comprising: a) a stator having a number of conductors that generate a plurality of magnetic fields when energized; and b) a body substantially enclosing the conductors, wherein the body has a thermal conductivity. At least 0.7 watts / (meter · ° K) and a dielectric strength of at least 250 volts /
A body comprising a mill (9842.52 v / mm) phase change material. 109. A motor and disk assembly, the motor comprising: a) a stator having a number of conductors that generate a plurality of magnetic fields when current is passed; and b) a monolithic body made of a phase changing material. Wherein the body substantially encloses the conductor, and wherein the phase change material comprises the motor and disk assembly of the motor and disk.
And a body having a vibration damping effect that reduces harmonic oscillations in the range of 2000 Hz to 2000 Hz by at least 5 dB compared to a motor having the same unsealed stator. 110. The motor and disk assembly of claim 109, wherein the harmonic vibration reduction of at least 5 dB occurs in the range of 200 Hz to 2000 Hz. 111. A motor and disk assembly, the motor comprising: a) a stator having a number of conductors for generating a plurality of magnetic fields when current is passed; and b) a monolithic body of phase changing material. Wherein the body substantially encapsulates the conductor and the phase change material reduces audible noise of the motor and disk assembly at least as compared to a motor having the same unencapsulated stator. A motor and disk assembly comprising: the body having a 2dB reduced vibration damping effect. 112. The motor and disk assembly of claim 111, wherein the reduction in audible noise is at least 5dB compared to a motor having the same unencapsulated stator. 113. The motor and disk assembly of claim 111, wherein the reduction in audible noise is at least 10dB compared to a motor having the same unencapsulated stator. 114. A method of manufacturing a hard disk drive, comprising: a) forming a stator composed of a laminated steel core and wire windings; b) substantially enclosing the stator in a body made of a phase changing material. Forming a stator assembly; c) ultrasonically cleaning the stator assembly; d) assembling the stator assembly with bearings, shafts and hubs to form a spindle motor; and e) forming the spindle. Assembling the motor with the hard disk drive; and manufacturing the hard disk drive. 115. The steel laminate and the wire,
115. The method of claim 114, wherein the method is not cleaned after being incorporated into a stator and before being encapsulated to form the stator assembly. 116. A method for manufacturing a spindle motor, comprising the steps of: a) manufacturing a steel laminated core, wire windings, and terminals to a stator; b) enclosing the stator in a main body made of a phase-change material; C) incorporating the stator assembly into a spindle motor, the spindle motor meeting particle emission standards of the hard disk drive manufacturing industry. Method. 117. A method of manufacturing a hard disk drive having a high data density, the method comprising: a) configuring a spindle motor having reduced vibration characteristics, wherein: i) a phase change material A) a stator assembly having a stator substantially enclosed in a body comprising: ii) a rotatable disk support member to which a magnet is coupled; iii) a shaft; iv) a bearing surrounding said shaft; One of a shaft and the bearing is fixed to the stator assembly, and the other of the shaft and the bearing is fixed to the rotatable disk support member, constituting the spindle motor. B) the hard disk having a magnetic storage medium on the disk support member; Hard disk drive with high data density, comprising: incorporating the spindle motor into a disk drive; and c) obtaining the advantage of reduced vibration characteristics of the motor by narrowing the data tracks of the magnetic storage medium. Device manufacturing method. 118. The data track is 2.54c
118. The method of claim 117, wherein the method is spaced to have 10,000 tracks per m (inch). 119. A hard disk drive with high data density, comprising: a) a spindle motor having reduced vibration characteristics, the spindle motor comprising: i) a stator substantially encapsulated in a body made of a phase changing material. A) a rotatable disk support member to which a magnet is coupled; iii) a shaft; iv) a bearing surrounding the shaft; and v) one of the shaft and the bearing is the stator assembly. And the other of the shaft and the bearing is fixed to the rotatable disk support member; and b) a magnetic storage medium provided on the disk support. And 10000 tracks per inch With a spaced data tracks to have, including, and said magnetic storage medium, a hard disk drive. 120. A method of manufacturing a hard disk drive with a high speed spindle motor having improved impact resistance, comprising: a) substantially enclosing the stator in a body made of a shock absorbing phase changing material; b) Attaching one of a bearing and a shaft surrounded by the bearing directly to the body; c) connecting the other of the bearing and the shaft with a magnet proximate the stator. D) attaching the body to a housing of a hard disk drive; e) attaching a magnetic data storage medium to the hub; f) thereby allowing the phase change material to absorb shocks ,
A method for manufacturing a hard disk drive, comprising: minimizing the transfer of energy between the housing and the magnetic storage medium. 121. The shock absorbing thermoplastic material, wherein the stator assembly is 300 Hz to 2000 Hz.
120. The method of claim 120, wherein the harmonic vibrations in the range are damped by at least 5dB compared to a spindle motor having the same unencapsulated stator. 122. The method of claim 121, wherein the reduction of the harmonic vibration of at least 5 dB is performed in a range from 200 Hz to 2000 Hz. 123. The shock absorbing thermoplastic material, wherein the stator assembly damps vibration so that audible noise is reduced by at least 2 dB compared to a spindle motor having the same unencapsulated stator. Item 120. The method according to Item 120. 124. The shock absorbing thermoplastic material wherein the stator assembly damps vibration so that audible noise is reduced by at least 5 dB compared to a spindle motor having the same unencapsulated stator. Item 120. The method according to Item 120. 125. The shock-absorbing thermoplastic material, wherein the stator assembly damps vibration so that audible noise is reduced by at least 10 dB compared to a spindle motor having the same unencapsulated stator. Item 120. The method according to Item 120. 126. The method of claim 120, wherein the shaft is secured to the thermoplastic body by molding the shaft with the stator into the thermoplastic body. 127. The bearing is fixed to the thermoplastic body by press fitting.
The method of claim 120. 128. A high speed spindle motor comprising: a) a stator assembly; and b) a rotatable hub having a magnet, the magnet being operatively connected to the hub at a location proximate the stator. C) a shaft; and d) a hydrodynamic bearing surrounding the shaft, wherein one of the bearing or the shaft is fixed to the stator assembly, and A high-speed spindle motor, the other being fixed to the hub. 129. The stator assembly includes a stator having a plurality of conductors that generate a plurality of magnetic fields when energized, and a body made of a phase changing material enclosing the stator. 129. The high speed spindle motor according to claim 128, fixed to the body. 130. A method of manufacturing various spindle motors, comprising the steps of: a) providing a plurality of stators having magnetic poles with windings, the stators each comprising: i) the number of turns of wire per winding; Ii) the number of magnetic poles; iii) the diameter of the stator; iv) the thickness of the stator; and b) a common mold, wherein one or more of the properties are configured to be different from each other. Providing a forming tool; c) holding a first stator within the molding tool and adding a phase changing material to substantially enclose the first stator; d) enclosing the stator. Forming a first type of motor using the first and second bearings and a shaft; and e) holding a second stator having characteristics different from the first stator in the mold and providing a phase changing material. Add Substantially encapsulating said second stator; and f) using the encapsulated second stator, bearings and shaft to form a second type of motor. Production method. 131. A hard disk drive, comprising: a) a base assembly substantially enclosing a stator and including a body of phase change material supporting a shaft; and b) a hub having a magnet, wherein the magnet is Operatively coupled to the hub near the stator, the hub comprising:
The hub rotatably supported on the shaft by bearings; c) one or more disks supported on the hub; d) one or more disks for accessing data. A read / write head configured to record data or read data from these disks. 132. The base assembly further includes:
A second supported by a body made of the phase changing material;
A second shaft, wherein said second shaft is
132. The hard disk drive of claim 131, wherein the hard disk drive supports a write head in a position proximate to the one or more disks to operate on the one or more disks. 133. The main body made of the phase change material,
2. A monolithic body made of a thermoplastic material.
32. The hard disk drive according to 31. 134. The system further includes a cover, wherein the cover comprises:
132. The hard disk drive of claim 131, attached to the body of the phase change material and cooperating with the body to provide a housing for the hard disk drive. 135. The stator according to claim 1, wherein the stator includes a plurality of magnetic poles and a core having a winding around the magnetic pole.
32. The hard disk drive according to 31.