TW530130B - Axial vibration prevention mechanism and brushless motor having the mechanism - Google Patents

Abstract

The object of this invention is to stop a thrust bearing so as to prevent axial vibration by means of biasing a rotor toward a thrust bearing direction by a simple structure. This invention comprises: a rotor (R) having a driving magnet (3) and a rotor yoke (1) mounted inside the driving magnet; a shaft (2) mounted on the center of the rotor; and a bearing housing (9) having a radial bearing (7) and a thrust bearing (8) to rotatably support the shaft. Further, a preload generation magnet (4) is arranged around the shaft serving as means for biasing the rotor toward a thrust direction in order to support the base end of the shaft on the thrust bearing, and to enable the bearing housing (9) made of a magnetic material to be opposed to the preload generation magnet with a gap formed therebetween.

Description

[Explanation of the invention] [Technical field to which the invention belongs] The present invention relates to a brushless motor that uses a rotary drive to remove a spindle, and also records a spindle of a magnetic disk. …, There is this axial vibration prevention mechanism [know-how] In recent years, CD-ROM, DVD, and DVD-based 5fU recorded magnetic disk systems require high-speed rotary drive, and the magnetic drive system is required to rotate to drive the magnetic system in the stator. In the stator seat, the second part is equal to the "then." In this way, the bearing housing of the horse and the bearing is provided inside the cylinder of the bearing, and a thrust bearing is provided to pivotally support the magnet that is freely supported by the rotor that constitutes the roller. The radial bearing and shaft base of the central shaft are fixed, and the iron core is fixed to the outer periphery of the cylinder of the bearing housing. At this fixed position, a plurality of protrusions protruding from the central σP toward the half-duty direction are returned to the drive coil. An armature stator is formed. Furthermore, a ring-shaped magnet is fixed on the inner peripheral surface side of the cylinder of the roller magnetic vehicle, and the magnet is arranged opposite to the salient pole blades of the stator through a gap. Because of the general information Record the uneven distribution of the weight in the axial plane of the magnetic disk. In such a spindle motor, as the motor on which the magnetic disk is mounted rotates at a high speed, the imbalance of the magnetic disk movement in the direction of the forward axis will force and cause longitudinal vibration. As a result , The same as the reading error of disk information There are problems such as the vibration of the driving device itself, and the noise becomes larger. "The basic method of the horn resolution problem is in the rotation of the motor, and the aforementioned unbalanced knife force is added to the stable force as a preload. The roller must be given the potential energy moving in the direction of the axis. The means for arranging this pre-compression is to use the center of the blade staggered from the stator core ^ Zhang dimension toward the "national standard grid 0 × 2 ^ · (Please read the precautions on the back before filling the nest (This page)

530130 V. Description of the invention (2 Air magnetism and the center of the magnetic circle center of the opposite ring-shaped roller magnet. The stator center of the blade is located at the side of the output shaft staggered. Thrust: the attraction of the direction 'It is possible to give the preload of the roller to the thrust side mouth b. Nu [the problem to be solved by the invention] However, the aforementioned method of staggering the magnetic center usually cannot obtain the power of potential energy. It can reduce the magnetic characteristics of magnets, increase the leakage flux, generate strong magnetic noise, and have the disadvantages of being installed and causing failures. It is a system that provides a simple solution to solve the aforementioned shortcomings. Centrifugation of magnetic potential of the rotor toward the thrust bearing

: Ma: The axial vibration prevention mechanism with superior properties and a brushless unit with the same mechanism [to solve the problem J To solve the above problems, as shown in item 丨 of the scope of the patent application, the rollers are equipped with a driving magnet and The drive magnet is mounted on the inner rotor magnetic vehicle; the shaft is installed at the center of the roller; and the bearing housing is provided with a radial bearing and a thrust bearing supporting the shaft so that it can rotate freely, and A magnet for preload generation is arranged around the shaft as a means for imparting potential energy in the thrust direction of the rotor to support the base end portion of the shaft to the thrust bearing and to make the bearing a magnetic body. The shell milk is opposed to the magnet for the pre-pressure generation through the gap. Doing so will not affect: Using the stone, the potential energy of the rotor in the axial direction can be imparted. As the aforementioned means for imparting potential energy, specifically, if applied The paper size of the patent is applicable to the Chinese National Standard (CNS) A4 specification (2) × 297 mm

Order — (Please read the precautions on the back before filling this page) 530130 V. As shown in item 2 or 3 of the description of the invention, because the potential energy-imparting device is placed around the shaft of the rotor yoke, the preload occurs A magnet and at least a part of the bearing housing opposite to the magnet for the preload generation are made of magnetic material, so the magnet for the preload generation is formed into a ring, and is arranged in the aforementioned rotor magnetic loss by magnetic adsorption. Shaft insertion section. In this way, it is not necessary to consider the space in which the magnet for the preload generation is arranged in space. As another specific method, as shown in item 4 or 5 of the scope of patent application, the aforementioned device for imparting potential% is disposed in the bearing housing when the shaft is installed, and becomes the preload generating device around the shaft. The magnet and the rotor yoke are made of magnetic material at least in the part facing the magnet. The pre-press generation is formed by a magnet system in a ring shape. It is arranged on the top of the bearing housing by magnetic adsorption. Special consideration is given to the arrangement space of the magnet for preload generation, and the magnet for preload generation can be reliably held by its strong magnetic force. Moreover, as shown in item 6, 7, or 8 of the scope of the patent application, another specific means is to arrange a magnet for preload generation in the aforementioned radial bearing, and use the shaft as at least a part of the magnetic circuit to create a direction to impart to the aforementioned rotor. The potential energy of the thrust bearing side movement, in detail, the aforementioned pre-compression magnet is arranged at least on the base end side of the shaft, and the pre-compression magnet is arranged on the top of the bearing housing. In this way: there is no need to consider the space for the magnet for preload generation. In this way, the magnet system for preload generation is arranged on the top of the bearing housing as shown in item 8, 9 or item of the patent application, and the aforementioned magnet system is composed of the radial bearing itself. More specifically, the aforementioned radial bearing Porous sintering: Stone powder alloy contains oil and is magnetically oriented in the axial direction. In this way, since the pre-production magnet becomes the same as the bearing, it is not necessary to install it separately. : Staff pressure (please read the notes on the back before filling in this page) Ordering 丨 This paper size applies the Chinese National Standard (CNS) A4 specification (21〇 > < 297mm) WIU30-^ V. Invention ^ η * —— In addition, as shown in item 11 of the patent patent claim No. 2 and 3 of the brushless motor 2 and 3 including such an axial vibration prevention mechanism, the patent application scope includes i, '4' 5 '6, 7, and 8 The axial vibration prevention mechanism of item 9, 9 or 〇, the bearing housing in the vibration prevention mechanism is arranged on the stator base, and the rotor is driven by the armature coil arranged around the bearing housing. If b has an unbalanced component in the axial direction, it can suppress the vibration of the brushless motor. [Embodiment of Invention] Next, an embodiment of the present invention will be described with reference to the drawings. "Figure 1 shows a front view of a cross section of a main part of a motor that includes a brush motor of an axial vibration prevention mechanism according to the first embodiment of the present invention. Figure 2 shows the rotor magnetic vehicle i shown in Figure i with magnetic materials and The front view of the cross section of the main part of the structure formed by non-magnetic material. Figure 3 is the front view of the cross section of the main part of the structure formed by replacing the bearing housing of the motor shown in m with magnetic and non-magnetic materials. Sectional front view of a main part of a brushless motor including an axial vibration prevention mechanism in a second embodiment of the present invention. Fig. 5 shows a main part of a brushless motor including an axial vibration prevention mechanism in a third embodiment of the present invention. Sectional front view. Fig. 6 is an enlarged main-part cross-sectional view of Fig. 5. Fig. 7 shows an enlarged main-part cross-sectional view of a modification of Fig. 5. Fig. 8 shows an enlarged main part of a fourth embodiment of the present invention. Cross-sectional view. Fig. 9 shows a cross-sectional view of the enlarged main part of the first modified example of Fig. 8. Fig. _ Shows an enlarged main-face view of the second modified example of Fig. 8. The paper size applies the Chinese National Standard (CNS). A4 specifications (210X (No. 297) (Please read the notes on the back before filling out this page)

530130 A7 V. Description of the invention (Figure 11 is a cross-sectional view of the enlarged main part of the fifth embodiment of the present invention. Figure 12 shows the enlarged main part wearing view of the modified example of Figure 11: Figure 13 is a plastic model of the present invention The main part of the bearing structure is enlarged in section. A perspective view. In the first figure, the rotor yoke formed in the shape of an inverted cup 丨 the central part is fixed on the shaft 2 and the inner peripheral side of the magnet 3 and the rotor yoke 丨On the peripheral surface la of the shaft 2 insertion part, the ring-shaped preload generating magnet 4 is fixed. On the one hand, the armature coil 6 is wound around the stator core 5, and the radial bearing 7 and thrust are inserted inside the central ring-shaped part 5a. The bearing 8 is a bearing housing 9 made of a magnetic material, and the car is fixed to the stator base 10 by the bearing housing 9. In addition, the bottom of the magnet 4 for preload generation is arranged close to the opening of the bearing housing 9, such as The gap T is maintained so as not to hinder the degree of rotation, and a green magnetic disk is mounted on the output side end of the shaft 2. The magnet 4 for preload generation is thus opposed to the magnetic bearing through the gap. The opening 9a of the casing 9 can be constantly attracted, so it can be often given Potential energy of the sub-yoke 1 moving in the direction of the base end of the shaft. That is, the shaft 2 is attracted to the direction of the thrust bearing 8. By its end, the thrust bearing 8 is often crimped and the pointed shaft is supported. Suppress the vibration of the shaft 2 up and down. In addition, if the rotor yoke is formed with a magnetic material, the pre-pressed iron 4 can directly adsorb the magnetic material around the shaft of the rotor with magnetic loss. The mechanical or mechanical fixing can obtain a strong fixing. In addition, the attraction force acting on the bottom 4a of the magnet 4 for the preload generation and the opening of the bearing housing 9 is a slight spoon gap. Peripheral face of magnet 4 and rotor yoke 1; when one of the attractive forces between ^ is large, the preload occurs.

t. (Please read the precautions on the back before filling this page) 530130 A7 ----------- B7 V. Description of the invention (6) Use of magnet 4 and peeling to the bearing housing 9 side . In the second figure, the rotor yoke 21 is constituted by a portion 21A made of a magnetic material to hold the driving zirconia 3 and a portion 21B made of a non-magnetic material through which the shaft 2 is inserted. In this structure, the magnet for preload generation * may be fixed to the insertion base of the shaft with an adhesive or [entry, etc.], but as shown in FIG. 2, a plate 22 made of a magnetic material such as an iron plate is pressed. The shaft P of the insertion portion 2B of the input shaft 2 is as described above. As long as the magnet 4 for magnetic adsorption preload generation is used, a strong fixation can be obtained. In addition, it can prevent the damage or falling off of the magnet 4 for preloading. In addition, this exchange form will be composed of a non-magnetic material of the rotating table τ [Μτ7 is used as the shaft 2 of the rotor magnetic car 21 and can be inserted through 2 丨It is common for Β to reduce the thickness of the spindle motor. In FIG. 3, the bearing housing 19 has a stator seat 10 side as a non-magnetic material portion 19a | 4 and a pre-stress generating magnet 4 side is a magnetic material portion. Here, the function is the same as that of the first embodiment. In addition, when the shaft pump housing 19 is used in a complicated shape in this replacement form, a part thereof is made of a non-ferrous material such as a brass rod having good workability, that is, it has a great advantage when it is made of a non-magnetic material. As shown in FIG. 4, the structure of the motor is basically the same as that in the above-mentioned FIG. 1, but the difference is that the pre-pressure generating magnet 24 is magnetically attracted to the periphery 29 a of the opening portion of the bearing housing 29 made of magnetic material. The peripheral surface of the shaft 2 insertion portion of the rotor yoke of the inverted cup-shaped rotor made of magnetic material is disposed near the gap that does not hinder the rotation range. By using the magnet 24 for preload generation as shown in FIG. The peripheral surface u inserted through the gap opposite to the shaft 2 of the rotor yoke 丨 is often attracted, so it can often give the rotor yoke 丨 moving toward the base end of the shaft ^ 2 297 mm ) ΓΤ ~-

., Π— (Please read the notes on the back before filling out this page) 530130 A7 —______________ B7__ V. Description of the invention (7) " ^ 1 ~~ month b. In addition, the attractive force acting on the upper portion 24 of the magnet 24 for preload generation and the peripheral surface la of the shaft 2 insertion portion of the rotor yoke 1 is not as attractive as that of the pre-magnet 24 and the bearing housing 29. One of the attractive forces acting between the opening periphery 29 & is large, and the pre-pressing magnet 24 does not peel off to the rotor yoke i side. In addition, ferrous sintered bearings can be used for the material and form of this bearing, and copper-based sintered bearings, resin bearings, composite bearings, dynamic pressure bearings, static pressure bearings, etc. are not subject to any restrictions. FIG. 5 shows another embodiment of the magnet for preload generation, that is, while the shaft 2 made of a magnetic metal material is fixed at the center of a cylindrical rotor yoke made of a magnetic material, the inner surface is also closed. Magnet for fixed driving 3 ° Bearing housing 39 made of non-ferrous metal material that rotatably supports the rotor. A radial bearing 7 made of magnetic sintered metal containing oil in the central annular part and a shaft tip support the aforementioned. A thrust bearing 88 at the base end of the shaft and a ring-shaped magnet 39a for pre-pressing between the two are provided with a stator core 5 wound around the armature coil 6 on the outer periphery and fixed to the stator base 10 at the bottom. The structure of the bearing section will be described with reference to FIG. 6, in which the radial bearing 7 is formed in a middle structure with an upper and lower integral shape, and the end portion of the thrust bearing 88 is in contact with the N (north) and s (south) poles in the axial direction. The ring-shaped magnet 39a for magnetic preload generation. The inner diameter of the ring magnet 39a for preload generation is larger than the inner diameter of the radial bearing 7, and the outer diameter is set to be approximately the same as the inner diameter of the bearing housing 39, and a recess is formed on the bottom side of the bearing housing 9. A thrust bearing 88 is fitted in the recess. The ring magnet 3 9 a for preload generation is formed in a stepped manner in contact with the inner diameter of the recessed surface, and becomes the paper size applicable to the Chinese National Standard (CNS) A4 specification (2) × 297 mm.

I Stare (Please read the precautions on the back before filling this page) 530130 V. Description of the invention (The outer diameter of thrust bearing 88 can be embedded in the stepped inner diameter of ring magnet 39a. According to this structure, the thrust bearing of shaft 2 The base end portion on the 88 side can be provided without the ring magnet 39a for penetrating preload generation. Therefore, when the miscellaneous side of the rotor of the ring magnet for preload generation is used as the N (north) pole, The magnetic field lines are as follows: the dotted line front A passes the ring magnet 39a for preload generation—radial bearing 7—similar to the magnetic circuit of the ring magnet 39a for pre-house generation. Due to the magnetic attraction caused by the magnetic field lines, the shaft 2 is under thrust. The bearing 88 also attracts in the direction, and the shaft 2 can continue to be attracted to the thrust bearing direction. In addition, the strength of the attraction is determined by the material f and shape of the ring magnet 39a and the shaft 2. The radial bearing 7 and the thrust bearing 88 The positional relationship can be adjusted. Fig. 7 shows the radial bearings of Figs. 5 and 6 as the rotor yoke side 7th floor thrust bearing side 7b. In particular, the thrust bearing side radial bearing 7b Formed by sintered gold layer of oil-containing magnetic body. Figure 2 shows the same magnetic circuit, and the variable wire 2 can be continuously attracted to the thrust bearing direction. As a modification of Figures 5 and 6, it can be made as shown in Figure 8. That is, it can be used as a ring for preload generation. Instead of a magnet, the bearing itself is made of a long-lasting magnet that can be magnetized in the direction of the rotation axis, and it is magnetized in the direction of the rotation axis to make a vertical positive and negative radial bearing 7C. The radial bearing is formed on the bottom side of the bearing housing The recessed part, the thrust bearing 88 embedded in the recessed part is the same as that shown in Figs. 5 and 6. Since the radial bearing also has the pull of the ring-shaped stone for preload generation in Fig. 5, there is no need for an external permanent magnet. The magnetic circuit itself has the same magnetic circuit as in Fig. 6, and it becomes the direction that the shaft 2 can continue to be attracted to the thrust bearing. Fig. 9 is the deformed shape of Fig. 8 and the radial direction of the thrust bearing side is also solid.

530130 A7 1 —------— _____ Wuming (9 " instead of pre-bearing bearing and ring magnets, equipped with radial bearings 7d made of sintered metal containing oil as a permanent magnet, It supports the shaft 2 rotatably together with the radial bearing arranged on the upper part. Since the radial bearing 7d here also has the mechanism for the preload generation shown in Fig. 6, a magnet for the preload generation is required, which is the same as the bearing itself. It is magnetic and shows the same magnetic circuit as in Fig. 6, and the shaft 2 can be surely continued to be attracted to the thrust bearing direction. 苐 10 is the second deformed form of Fig. 8 as a magnet for preload generation, and it also acts as a permanent magnet. The radial bearing 7g made of sintered metal containing oil is arranged on the top of the bearing housing 9. Since the radial bearing 7g also has a preload generating function, there is no need for another permanent magnet, which is magnetic with the bearing itself, here The rotor yoke also presents a magnetic circuit, and the shaft 2 can be surely continued to be attracted to the thrust bearing direction. Figure 11 shows that the bearing itself is integrally formed of a magnetic sintered metal material that also has a permanent magnet to magnetize in the axial direction. change Completion of the preload generating radial bearing 7b. &Amp; If not, the preload generating radial bearing 7h presents a magnetic circuit through the rotor magnetic light i arrow, and the shaft 2 continues to be attracted to the thrust bearing direction. Fig. 12 shows a modification of Fig. Η. The thrust bearing side has the functions of Fig. 7 and $, and the rotor yoke side has the function of Fig. 10. In this configuration, the magnetic lines of force of the aforementioned magnetic circuit are formed. A, B, and C are more complex, and a stronger preload is available. As mentioned above, the bearing is made of a magnet, and the sliding property becomes a problem. The size of this paper applies the Chinese National Standard (CNS) A4 (210X297). 12 ---------------------—— r- (Please read the notes on the back before filling in this page) Order — 530130

DESCRIPTION OF THE INVENTION The whole may be thinned and covered with a sliding resin. Next, the manufacturing methods of the sleeve-shaped radial directions m7d, 7g, and 7h that have the above-mentioned permanent magnets are described below. First, f is used as the first method. As shown in FIG. 13, the unmagnetized magnet 77 composed of sintered magnetic stone or dead magnetic stone is used to form a sleeve bearing 7 with a desired size of a sliding resin 12. Mold, magnetically oriented in the axial direction to form a radial bearing that has both water and magnets. As a second method, a ferromagnetic powder such as ferrite magnet powder or rare earth magnet powder is mixed with iron-based sintered metal powder composed of% (iron), CU (copper),% (steel), etc. After the size of the mold plus mold, the size is sintered and fresh. The magnet is magnetized in the axial direction 'and a radial shaft 2 is formed which contains lubricating oil and contains permanent magnets. Even in any of the foregoing formation methods, the strength of the magnetic force is in accordance with the intrusion ratio of the magnetic powder. The size of the magnet section can be adjusted by the magnetic machine, and can also be arbitrarily implemented. [Inventive effect] As described above, according to the first item of the scope of the patent application, since the driving magnet "can impart potential energy to the rotor in the axial direction, even the high-speed rotation type" can provide an axial direction to prevent the rotor from vibrating in the axial direction. The vibration prevention mechanism becomes a brushless motor that can control vibration even if there is damage due to imbalance in the axial direction due to item u of the patent application scope. As shown in item 2 or 3 of the patent application scope, there is no need to consider the space for the magnet for preload generation. Even as shown in item 4 or 5 of the scope of patent application, since it does not require special consideration of the space for the magnet for preload generation, it can be made thin and preloaded.

This paper size applies to China National Standard (CNS) A4 specification (21〇 × 297) (Please read the precautions on the back before filling this page)

530130 Description of the invention (/ ^ The magnet for health can be reliably held by its strong magnetic force. :: As shown in item 6, 7 or 8 of the scope of patent application, since it becomes not = special consideration must be given to pre-bridging magnets The configuration space can be made thin. As shown in item 8, 9 or; U) of the patent application scope, since the pre-sedimentary magnet becomes shared with the bearing, no additional installation is required, and the configuration as a pre-pressured magnet can be ignored. space. [Brief description of the drawings] Fig. 1 is a front view of a cross section of a main part of a brushless motor having an axial vibration prevention mechanism according to a first embodiment of the present invention. Fig. 2 is a cross-sectional front view of the main part of the rotor yoke in Fig. 丨 with another structure. Fig. 3 is a cross-sectional front view of the main part of another structure of the bearing housing in Fig. 丨. Fig. 4 is a sectional front view of a main part of a brushless motor having an axial vibration prevention mechanism according to a second embodiment of the present invention. Only (Please read the precautions on the back before filling out this page)-, OK | Figure 5 shows a front view of the main section of a brushless motor with an axial vibration prevention mechanism in a third embodiment of the present invention. FIG. 6 is a cross-sectional view of an enlarged main part of FIG. 5. Fig. 7 is a cross-sectional view showing an enlarged main part of a modification of Fig. 5. Fig. 8 shows an enlarged main-part cross-sectional view of a fourth embodiment of the present invention. Fig. 9 shows an enlarged main-part cross-sectional view of the first modified example of Fig. 8c. Partial cross-sectional view 14 530130 A7 B7 V. Description of the invention (l2) FIG. 11 shows an enlarged partial cross-sectional view of the fifth embodiment of the present invention. Fig. 12 is a cross-sectional view showing an enlarged main portion of a modification of Fig. 11. Fig. 13 is a perspective view showing a cross section of an enlarged main part of a plastic model bearing structure according to the present invention. (Please read the precautions on the back before filling out this page). Yes, 15 This paper size applies to China National Standard (CNS) A4 (210X297 mm) 530130

Description of the Invention Component Number Comparison 1 ····················································································································· · Armature coil 7… radial bearing stone 7a · 7b · 7c · 7d · 7g · 7h. 7z. Rotor magnetic vehicle side thrust bearing side up and down integral radial bearing radial bearing radial bearing pre-pressurization moon radial bearing Sleeve-shaped car by bearing 8 ... Thrust bearing 9 ... Bearing housing 9a ... Opening portion 10 ... Stator base 12 ... Resin 19 ... Bearing housing 19a ... Non-magnetic material portion 19b ... Magnetic material portion 21 ... Rotor yoke 21A ... part 21 holding magnet 3 ... shaft 2 insertion part 22 ... plate 24 ... magnet 24a for preload generation 24 ... upper part 29 of magnet 24 ... bearing housing 29a ... opening periphery 39 … Bearing housing 39a ··· Ring magnet for preload generation 77 ... Unattached magnet 88 ... Thrust bearing R ... Axle T ... Rotary table This paper applies Chinese national standard (⑽) A4 (210X297) f Please read the notes on the back before filling in this page;

Claims (1)

530130 Patent application range 2. 3. 4. 5.. An axial vibration prevention mechanism, including:: Zizi 'is a rotor magnet with a driving magnet and the driving magnet on the inside; Installed in the center of the roller; and the bearing makes it rotatable and supports the radial bearing and thrust of the shaft that has just escaped. The magnet for preload generation is arranged around the shaft, which means that the force of the rotor and the rotor is facing in the thrust direction. It is possible to support the base end portion of the bearing to the aforementioned thrust bearing, and make the bearing housing made of magnetism face the axial vibration of the pre-M generation magnet through the gap through the gap, and declare the first patent scope. The preventive mechanism, in which the device for imparting potential energy, is arranged around the aforementioned magnetic light shaft of the rotor, and the magnet for the pre-house generation and the magnet bearing housing opposite to the pre-pressure generation are at least partially composed of magnetic materials. Shi claimed that the axial vibration prevention mechanism of the second item of the patent scope, in the foregoing, "forms a ring with a magnet system" and is arranged on the shaft insertion portion of the rotor yoke by magnetic attraction. For example, the axial vibration prevention mechanism of item 1 of the patent application range, where the front position of the front shaft U and the front shaft are arranged in the bearing narrative when the aforementioned shaft is installed and become the aforementioned pre-compression magnets surrounding the shaft. The rotor yoke is made of a magnetic material at least in a portion facing the magnet. Shishen: Patent No. 4 for the axial vibration prevention mechanism, in which the front magnet is used to form a ring-shaped ground, and is arranged on the body by magnetic adsorption. The paper size of Λ 尺度 applies the Zhongguan standard. (CNSy A4 specifications (210X297 public director) 17 530 130 A8 B8 C8