JP3745975B2 - Flat rotating yoke type brushless motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flat rotating yoke type brushless motor suitable for use in a silent notification means of a mobile communication device, a disc media signal detection slide motor, a disc media drive spindle motor, and the like, and a method of manufacturing the same.
[0002]
[Prior art]
Conventionally, as a flat small brushless vibration motor used for a silent notification means of a mobile communication device, the present applicant has previously disclosed Japanese Utility Model Laid-Open No. 4-137463 (utility model registration No. 2549357), Japanese Patent Laid-Open No. 10-248203, and the like. is suggesting.
Further, as a similar one, as shown in Japanese Patent Laid-Open No. 11-98761, a rotor case whose side surface is folded and eccentric is proposed.
However, since these are not rotary yoke types but cored types, there is a problem that current consumption increases due to magnet adsorption loss and eddy current loss.
Further, in such a configuration as shown in Japanese Patent Application Laid-Open No. 11-98761, the material of the normal rotor case is thin steel having a specific gravity of about 7, so that the amount of eccentricity is small and impractical. For this reason, as a small brushless vibration motor, a shallow cylindrical magnet is disposed inside a rotor case constituting a magnetic circuit, and a semi-cylindrical tungsten alloy is formed on the outside. For example, as shown in FIG. 1 of Japanese Patent Application Laid-Open No. 2000-166173. There is also a thing.
Further, as a picking motor for media signal detection by integrating a pinion with a rotor, the present applicant has proposed a coreless brush type as shown in FIG. 5 of Japanese Patent Laid-Open No. 2000-286030. Further, as a disk media driving spindle motor, a cored type brushless motor is known in which a media mounting turntable is arranged on an output shaft.
[0003]
[Problems to be solved by the invention]
However, in the structure of the vibration motor as described in JP 2000-166173 A, the eccentric weight portion must protrude from the turning outer diameter of the rotor, so this risk is avoided and the cover is made to be easy to handle. There is no choice but to attach it, and there is a dislike that the size becomes large in the radial direction. In other words, the larger the eccentric weight in order to increase the amount of vibration, the more sacrificing the radial size. By the way, as shown in FIG. 6, as a flat brushless motor used in a rotary yoke type, for example, a headphone stereo, a flat magnet M and a magnetic field of this magnet are provided with a stator St composed of a plurality of printed wiring coils C interposed therebetween. If the magnetic body m to be received is provided with a rotary yoke rotor Ro that faces the central pulley via an axial gap, the brake loss due to the magnetic attraction force of the rotor is reduced, and a reduction in current consumption is expected. However, because the stator is separated from the stator base due to the rotary yoke type, a feed lead is required to feed power to the stator in a configuration that avoids exposing one of the rotating parts. There is a problem that cannot be done.
In addition, since the rotating yoke type has a stator in between, the rotating yoke that faces the magnet must be mounted in the last place, so that it is not usually fixed and is simply placed in order to mount it without changing other parts. It must be. Therefore, it has been difficult to adopt a spindle motor in which a media disk must be mounted on the rotating yoke portion even if low current consumption can be expected.
[0004]
A first object of the present invention is to make it possible to easily fix a stator with a simple configuration although it is a rotary yoke type and to be directly attached to a printed wiring board on the equipment side.
A second object is to provide a spindle motor for driving a media disk that can reduce the thickness by making the rotary yoke part a turntable, reducing the thickness of the turntable so that low current consumption can be obtained.
And the 3rd objective provides the geared motor which has a pinion in a rotation yoke part.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, a rotary yoke type brushless motor as in the invention shown in claim 1 and a resin-made stator base (B) together with a bearing holder portion (B3) positioned at the center, A stator (S) made up of a printed wiring board having a plurality of air-core armature coils (1) provided on the stator holder portion is integrally mounted. The rotors (R, R1, R2, and R3) that are combined via an axial gap with the stator in between are disposed on the magnet holder (4) attached to the shaft (6) and the magnet holder. a flat magnet (2) to form a disengagement prevention part (5d) by at least partially embedded in the resin body (3, 33 and P) in those receiving the magnetic field of the magnet magnetic Allowed to face each other with a (5,55,56 and 57) axial direction gap is derived laterally while so slightly protrudes from the top to the stator holder as a feeding terminal (B1) to said stator As described above, this can be achieved by embedding in the resin stator holder portion and connecting the air-core armature coil terminal to the power supply terminal at the top of the stator holder portion.
Specifically, as shown in claim 2, at least a part of the resin body (3) functions as a turntable for mounting a media disk, and the magnetic body is constituted by a magnetic path plate (5). road plate also because it achieved was also allowed to function as a media disk chucking spring made thin magnetic stainless steel.
Further, the magnetic material element as shown in claim 3 in one side is exposed to the air gap side, the other surface is formed by magnetic path plate to be at least diaphysis of the resin turntable (7) (55), said The disc chucking spring (7a) may be formed of the same resin integrally with the turntable.
Further, as shown in claim 4, a high specific gravity member may be included in the resin body (33), and a part of the resin body (33) may be cut away to be eccentric so as to obtain vibration .
According to a fifth aspect of the present invention, one surface of the magnetic body is exposed to the air gap side and the other surface is embedded in the resin body , and the resin body forms a pinion (P) by forming a gear on the outer periphery. It may be a mold.
[0006]
According to the first aspect of the present invention, the stator can be easily fixed and connected, the power supply lead is not required and can be directly attached to the printed wiring board, and the magnetic plate is prevented from falling off even if one side is exposed in the gap. There is no risk of falling off due to the magnetic force of the opposing magnet.
According to the second aspect of the present invention, the magnetic flux can increase the magnetic flux density of the magnetic plate, so that the motor characteristics can be improved, and the media disc can be centered and held by the magnetic plate itself.
According to the third aspect of the present invention, since there is a magnetic path plate, the gap magnetic flux density is increased, and the disk medium can be easily placed with the resin itself.
According to the fourth aspect of the present invention, the vibration motor can be a rotary yoke type with little loss .
According to the fifth aspect of the present invention, since there is a magnetic path plate, the gap magnetic flux density increases, and a geared motor can be obtained without any special pinion .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a first embodiment of the present invention and is a longitudinal sectional view of a flat rotary yoke type brushless spindle motor.
FIG. 2 is a longitudinal sectional view of a modification of the motor of FIG.
FIG. 3 shows a second embodiment of the present invention and is a longitudinal sectional view of a flat rotary yoke type brushless vibration motor.
FIG. 4 is a plan view of FIG.
FIG. 5 shows a third embodiment of the present invention, and is a longitudinal sectional view of a flat rotary yoke type brushless geared motor.
[0008]
Hereinafter, the configuration of the present invention will be described based on each embodiment shown in the drawings.
FIG. 1 shows a three-phase axial gap type rotary yoke type brushless spindle motor, that is, the stator S is composed of a printed wiring board 1a on which a wound type air-core armature coil 1 is mounted, which is not described in detail here. However, the wound type air-core armature coil 1 is composed of nine pieces in which three phases are connected in series. The stator S is placed on a rising portion B2 of a resin-made stator base B in which a power supply terminal B1 is embedded, and a power supply terminal 1b of the wire wound core armature 1 is soldered to the tip of the power supply terminal B1. Yes. Inside this rising portion B2, a flat ring-shaped magnet 2 magnetized with 12 poles NS alternately with a stator S in between and a magnet 3 made of resin as a magnetic material with gaps therebetween. The magnetic poles are closed with the NS poles facing each other, and further, a magnet holder 4 that holds the flat ring-shaped magnet 2 and a magnet that holds the resin magnet 3 that functions as a turntable. A path plate 5 is provided. The magnetic path plate 5 is made of thin magnetic stainless steel, and has at least one chucking spring portion 5a having a function of placing and lightly holding a media disk and a flat functioning as a magnetic path. It consists of part 5b. The magnetic path plate 5 is further provided with a hole 5c and a drop-off preventing portion 5d through which resin such as a cut and raised portion is inserted so as not to be peeled off by the magnetic force of the flat ring-shaped magnet 2 that is opposed to the magnetic path plate 5. A part of the resin magnet 3 extends upward using the hole 5c to form a media disk attracting magnet portion 5e that also serves as a disk placement guide. ing. The magnet holder 4 includes a recess 4a that escapes from the shaft support B2 raised from the resin stator base B, and a central burring portion 4b following the recess 4a. The shaft 6 is press-fitted and fixed to the burring portion 4b. is doing.
The outer peripheral portion 3a of the resin magnet 3 has a media disk mounting portion 3b bulged. A thin friction sheet F is affixed here to complete the rotary yoke rotor R. As a manufacturing method for producing a level as a turntable, the flat ring magnet 2 and the magnet holder 4 are attached to the shaft 6. After that, the stator S is mounted, placed on the reference jig J1, and fitted with the magnetic path plate 5 functioning as a turntable on the rotating yoke side with a clearance of 0.1 mm or less with respect to the shaft, and horizontally placed on the friction sheet F After J2 is applied and the surface blur is corrected using the gap, the tip 6a and the central boss 6a of the magnetic path plate 5 are welded to the shaft 6 with a laser or the like.
If such a manufacturing method is adopted, the turntable and the shaft are securely fixed, and the variation in the thickness of the friction sheet F and the surface shake of the turntable can be corrected. In the figure, B4 is a bearing that is housed in the shaft support B2 and rotatably supports the shaft 6. As such a motor driving method, a three-phase unipolar or bipolar sensorless method is used.
In this way, when two magnets are opposed to each other, the magnetic flux density is improved by about 1.6 times as compared with one magnet, so that a low current consumption can be obtained.
[0009]
Hereinafter, although the modification of said embodiment and other embodiment are demonstrated, the same code | symbol is attached | subjected about the member which has the same member or the same function, and the description is abbreviate | omitted. In FIG. 2, the rotary yoke rotor R1 is a modification of the first embodiment described above, and the magnetic path plate 55 is made relatively thick so that the magnetic path plate 55 becomes the skeleton instead of the resin magnet. Further, the turntable 7 is made of a normal resin body. In this case as well, the leveling of the turntable 7 is preferably the same as in FIG. 1, but here the gap between the shaft and the rotary yoke rotor is 0.1 mm or less is sealed with anaerobic adhesive N. . The disk chucking spring 7a is formed of a resin body integrally with the turntable 7, and the media disk attracting magnet 8 is integrally formed of a sintered rare earth.
Here, the leveling jig J2 uses the curing time of the anaerobic adhesive while leveling at the time of rotation by giving inertia with the media disk size. If it does in this way, centering can also be performed by leveling jig J2 using hardening time, and the cost of a turntable can be reduced.
In addition, fixing time can also be shortened by making anaerobic adhesive into an ultraviolet curable type.
Further, in addition to each power supply terminal, a reference motor mounting terminal can be derived.
[0010]
3 and 4 show a brushless vibration motor in which the rotor is eccentric. That is, the eccentric rotor R2 is formed of a resin magnet 33 having a density of about 5 to 6 facing the flat ring-shaped magnet 2 and is integrally formed with the magnetic plate 5g, and one side of the resin magnet 33 is greatly cut away. Is eccentric. In this case, the magnetic plate 56 constitutes a recess 5g at the position of the portion 33a where one side is cut out, and is made flush with the side not cut out so that there is no gap loss. Further, since the central portion 33b of the resin magnet 33 bulges downward and is attracted to the magnet holder 4, it can be easily and reliably mounted. Here, the air-core armature coil 11 is a four-layer printed wiring type and is configured as a stator S2.
In the above-described embodiment, although the rotating outer diameter portion is circular, although it is an eccentric rotor, there is no danger during turning, so the cover is omitted, but during reflow soldering, etc. A stainless steel cover (not shown) with low thermal conductivity may be encapsulated.
[0011]
The one shown in FIG. 5 is employed in the axial gap type brushless geared motor according to the third embodiment of the present invention, and the rotor R 3 is provided with a pinion P integrated with the magnetic plate 57. This pinion P is used in combination with the first gear G as shown by the imaginary line, with the outer peripheral gear portion being inclined so that the rotor does not fly.
In addition, although each said embodiment showed what formed the air core armature coil by a winding type as a stator, what was made into the printed wiring type air core armature coil can also be comprised.
[0012]
The present invention can take various other embodiments without departing from the technical idea and characteristics thereof. Therefore, the above-described embodiment is merely an example and should not be interpreted in a limited manner. The technical scope of the present invention is indicated by the claims, and is not restricted by the text of the specification.
[0013]
【The invention's effect】
With this configuration, the stator can be easily fixed with a simple configuration although it is a rotary yoke type, and can be directly attached to a printed wiring board on the equipment side. The rotary yoke portion is used as a turntable. Thus, it can be applied to a spindle motor for driving a media disk that can obtain a low current consumption, or can be applied to a vibration motor with the rotating yoke portion eccentric, and a geared motor having a pinion in the rotating yoke portion can also be provided.
[Brief description of the drawings]
FIG. 1, showing a first embodiment of the present invention, is a longitudinal sectional view of an axial gap type rotary yoke type brushless spindle motor.
FIG. 2 is a longitudinal sectional view of a modified example of the motor of FIG.
FIG. 3 shows a second embodiment of the present invention and is a longitudinal sectional view of an axial gap type rotary yoke type brushless vibration motor.
4 is a plan view of the motor shown in FIG. 3. FIG.
FIG. 5 shows a third embodiment of the present invention and is a longitudinal sectional view of a brushless geared motor with an axial air gap type rotary yoke.
FIG. 6 is a longitudinal sectional view of a main part of a conventional rotary yoke brushless motor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Air-core armature coil 2 ... Flat ring magnet 3 ... Resin magnet 4 ... Magnet holder 5 ... Magnetic path board B ... Resin stator base 6 ... Shaft 7 ... Turntable S ... Stator R, R1 ... Rotor R2 ... Eccentric rotor P ... pinion

Claims (5)

A rotating yoke type brushless motor, a resin-made stator base (B), together with a bearing holder part (B3) located at the center, a stator holder part (B2) located outward is integrally raised , A stator (S) made of a printed wiring board provided with a plurality of air-core armature coils (1) is mounted on the stator holder portion, and a rotor (R) combined with an axial gap between the stators. , R1, R2, and R3) are a magnet holder (4) attached to the shaft (6), a flat magnet (2) disposed on the magnet holder , and a magnetic body for receiving the magnetic field of the magnet (3 , opposite of through at least part of a magnetic body formed disengagement prevention part to (5d) by being embedded (5,55,56 and 57) are axially voids 33 and P) Is, the embedded in the resin stator holder so as to be led out to the side as well as to slightly protrude from the top to the stator holder as a feeding terminal (B1) to the stator, the air-core armature to the power feed terminal A flat rotating yoke type brushless motor in which a coil terminal is connected at the top of the stator holder portion . As the rotor (R) , at least a part of the resin body (3) functions as a turntable for mounting a media disk, the magnetic body is composed of a magnetic path plate (5), and the magnetic path plate is made of thin magnetic stainless steel. The flat rotary yoke type brushless motor according to claim 1, which also functions as a media disk chucking spring . The magnetic material elements are formed by at least diaphysis become like magnetic path plate other surface resin turntable one side is exposed to the air gap side (7) (55), the disc chucking the same resin integrally with the turntable The flat rotary yoke type brushless motor according to claim 1, wherein a king spring (7a) is formed . The flat rotary yoke type brushless motor according to claim 1, wherein a high specific gravity member is included in the resin body (33), and vibrations are obtained by partially cutting and decentering the resin body (33) . 2. The magnetic body according to claim 1, wherein one surface of the magnetic body is exposed to the gap side and the other surface is embedded, and the resin body is made into a geared type by forming a gear on the outer periphery to form a pinion (P). Flat rotating yoke type brushless motor.

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