JP3568521B2 - Axial gap type brushless vibration motor with built-in drive circuit - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial gap type brushless vibration motor having a hall sensor and a drive circuit member, which is suitable for use as a silent notification unit of a mobile communication device.
[0002]
[Prior art]
A brushless motor requires a drive circuit in place of a brush and a commutator, but the above-mentioned conventional structures do not have a built-in drive circuit, and require four or more lead terminals for external attachment. There is a problem that it cannot be handled like a normal two-terminal DC motor.
In addition, in a normal brushless motor, the stator has a plurality of armature coils arranged evenly over the entire circumference, and the driving circuit components need other electronic components such as ICs, so that they cannot be built in very much. .
The present applicant has previously proposed a flat axial gap type brushless vibration motor which is a coreless slotless type and does not incorporate a drive circuit member. (See Utility Model Document 1 and Patent Document 2)
As a brushless vibration motor with a drive circuit, a cored type, a cored type in which an armature coil is wound around a plurality of equally arranged salient poles, and a non-circular type in which a drive circuit member is arranged on the side of the stator. Things are known. (See Patent Document 3)
However, such a type has a large size in the side direction, and the mounting efficiency of the printed wiring board on the set side is poor in the SMD method, and the thickness is unavoidably large because of the cored type. There is no sex.
Therefore, the applicant of the present invention has previously prepared a cored, slotless coreless type including a part of a plurality of armature coils, and provided a space, and provided a drive circuit member in this space. is suggesting. (See Patent Document 4)
[0003]
[Patent Document 1] Japanese Utility Model Laid-Open No. 4-137463 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-143767 [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-245103 [Patent Document 4] Japanese Patent Application Laid-Open No. 2002-142427 (FIG. 8 to 11)
[0004]
[Problems to be solved by the invention]
Therefore, the present invention further improves the axial gap type brushless vibration motor of FIGS. 8 to 11 of Japanese Patent Application Laid-Open No. 2002-142427 disclosed in the above-mentioned Patent Document 4 by using a thin and simple structure to stop the magnet. To provide a small brushless vibration motor that is thin and has sufficient strength while being able to incorporate drive circuit components and to be able to handle the same as a normal DC motor. Is what you do.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the yoke bracket (1, 11) includes a shaft support (1a) and a detent torque generating magnetic member disposed radially outward of the shaft support. Magnetic plate provided with a portion (1b) , a space (1e) surrounded by these as a non-magnetic portion , and a power supply terminal mounting portion (1d) further integrally and outwardly drawn out from the holding portion. A stator base (3) is attached to the yoke bracket, and two air-core armature coils (5A, 5B) connected to the stator base through a center and connected in a single phase are arranged. A single Hall sensor (H) is disposed on the detent torque generating section (1b) in plan view on the stator base so as not to overlap with each of these air-core armature coils in plan view, and further outputs an output of the sensor. Drive to receive Arranged at a position where the circuit member (D) is opposite the sensor, and the feeding terminal portion of at least the positive and negative two terminals derived outward is mounted on the power supply terminal carrying part from said stator base, the air-core eccentric rotor which is driven by the armature coil (R, R1) comprises a rotor yoke (6, 66) made of a magnetic material, an axial air-gap type magnet having a plurality of magnetic poles arranged in the rotor yoke (8) And an arc-shaped eccentric weight (9) arranged on the rotor yoke at the outer periphery of the magnet, and a central shaft holding portion (6a), and the eccentric rotor rotates via the shafts (2, 22). held freely in the shaft support portion, the cover member (10, 100) covering the eccentric rotor can be achieved in that assembled to the yoke bracket outwards opening.
More specifically, the base end of the shaft is fixed to the shaft support portion (1a) by laser welding first, and the eccentric rotor is fixed to the rotor yoke from the front end of the shaft. a fixed bearing in the center (7) is rotatably mounted, together with the cover member for covering the eccentric rotor (10) is mounted in the opening in the holding portion of the stator, the tip of the shaft of the cover member This can be achieved by being fitted into the central recess and laser-welded to the cover member from the outside .
The yoke bracket (11) is provided with a bearing (7) for rotatably supporting the shaft (22) on a shaft support (11a), and the eccentricity is provided on the bearing. The rotor (R1) is rotatably mounted via a shaft (22) fixed to the center of the rotor yoke, and the base end of the shaft is pivotally supported on the stator base side .
Further, it is preferable that these are integrated with the stator base with resin, including the axial gap type air-core armature coil and the drive circuit member .
The yoke brackets (1, 11) are formed of a magnetic metal plate having a thickness of 0.2 mm or less, and the rotor yokes (6, 66) are formed of a magnetic metal plate having a thickness of 0.15 mm or less. Is good.
[0006]
According to the first aspect of the present invention, the drive circuit member can be easily incorporated, the power supply terminal can be two terminals of positive and negative, and the magnet is stopped at a predetermined position by using the magnetic portion of the yoke bracket. Since the detent torque can be generated, and the eccentric weight is arranged in an arc shape within the thickness of the rotor and arranged on the outer periphery of the rotor, the movement of the center of gravity is large but the centrifugal force is generated at the time of rotation even though it is thin, Since the air gap is not sacrificed, the eccentric rotor also becomes thin. The power supply terminal can be protected by the power supply terminal mounting portion of the yoke bracket .
According to the second aspect of the present invention, the shaft can be fixed , and the shaft can be received by the cover even if there is an impact in the radial direction. Therefore, a thinner one can be adopted. Since it is extremely thin and is laser-welded to the cover member and the yoke bracket via a shaft , the motor is less likely to be deformed by impact .
According to the third aspect of the present invention, since the shaft can be configured to be of a rotating type and the base end of the shaft is pivotally supported, sliding loss can be reduced.
According to the fourth aspect of the present invention, since each member becomes a skeleton in addition to the reinforcement of each member by the resin, the impact property is improved.
According to the fifth aspect of the present invention, an axial gap type brushless vibration motor having a small size and a minimum thickness can be configured.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a first embodiment of the present invention, and is a cross-sectional plan view of a shaft-fixed axial gap type coreless slotless brushless vibration motor in a transverse direction.
FIG. 2 is a vertical sectional view taken along line AA of FIG.
FIG. 3 is a plan view of one member of FIG.
FIG. 4 is a plan view of another member of FIG.
FIG. 5 shows a second embodiment of the present invention, and is a longitudinal sectional view of a coreless, slotless, brushless vibration motor of a shaft-rotating type, in which an axial gap is provided.
[0008]
Hereinafter, a configuration of the present invention will be described based on each of the illustrated embodiments.
FIGS. 1 and 2 show a fixed shaft type air gap type coreless slotless type brushless vibration motor, that is, a brushless vibration motor, that is, the yoke bracket 1 is a stainless steel plate having weaker magnetism than an iron plate and has a thickness of 0.15 mm to 0.15 mm. A shaft support part 1a formed in a thin shape of 0.2 mm and protruding in the center in a burring shape, and three axial fields described later extending at an angle of about 120 degrees in the radial direction as shown in FIG. The magnetic part receives the magnetic field of the magnetic magnet and includes a detent torque generating portion 1b and a holding portion 1c that further extends in the radial direction and also serves as a ring-shaped reinforcement, and a part of the holding portion further extends in the radial direction. It protrudes to form a power supply terminal mounting portion 1d. The yoke bracket 1 constitutes a non-magnetic space 1e between the detent torque generating portions 1b as the above-mentioned magnetic portion in order to stop a magnetic pole of an axial field magnet described later at a specific position. .
On the upper surface of the yoke bracket 1 thus configured, a thin shaft 2 of 0.5 mm is press-fitted into the shaft support portion 1a at a base end, and a flexible printed wiring board or a glass cloth epoxy board is provided around the shaft. The yoke bracket 1 is further integrated with a heat-resistant resin 4 such as liquid crystal or polyphenylene sulfide, which can withstand reflow soldering, so that the yoke bracket 1 becomes a skeleton. The heat-resistant resin is also filled in the non-magnetic space 1e to reinforce the yoke bracket 1 and close the non-magnetic space 1e. Two air-core armature coils 5A and 5B are mounted on the stator base 3 so as to face each other, and are connected in series so as to be single-phase.
A drive circuit device including one Hall sensor H and a drive circuit member D formed as an IC is disposed between the air-core armature coils 5A and 5B.
Here, the positional relationship between the detent torque generating section 1b and the single-phase air-core armature coil is such that the effective conductor of the air-core armature coil is set in accordance with the magnetic pole of the magnet described later, and the shape is stopped by the magnetic force of the magnet. In this case, it is preferable that the setting is made so that the minimum stop torque is obtained.
Therefore, these stator members do not overlap in plan view, and can be configured to be thin.
Here, a part of the heat-resistant resin 4 is started up as guides 4a and 4b, and the air-core armature coils 5A and 5B are mounted using the guides 4a and 4b. And may be integrally molded.
On the other hand, an eccentric rotor R rotatably mounted on the shaft has a thin rotor yoke 6 of about 0.1 mm in which a sintered oil-impregnated bearing 7 is press-fitted into a burring-shaped bearing holding portion 6a provided at the center, and a lower surface adhesive. As shown in FIG. 4, the magnet 8 has an axial gap type magnet 8 and an arcuate weight 9 which is laser spot welded to the rotor yoke 6 at three points.
Here, in the rotor yoke 6, reinforcing ribs 6b are formed radially from the shaft holding portion 6a by utilizing dead spaces in the thickness direction to prevent deformation at the time of impact such as dropping. In the figure, reference numeral 6c denotes a tongue piece for positioning the magnet 8 and hanging it down for reinforcement at the time of bonding. Since the magnet 8 is magnetized in six poles and its driving principle is publicly known, its explanation is omitted.
The eccentric rotor R configured as described above is rotatably mounted on the shaft 2 via at least two laminated thrust washers S1 in order to reduce brake loss. Thereafter, a shallow cap-shaped cover member 10 made of a thin non-magnetic stainless material is covered, and the tip of the shaft is fitted into a burring hole 10a formed in the center of the cover member 10 via a thrust washer S2. Here, the burring hole is thinner than the shaft diameter so that the tip of the shaft 2 does not protrude, and this tip portion is laser-welded to the cover member 10 to prevent deformation. The opening 10 is assembled to the holding portion 1c of the yoke bracket 1 by laser spot welding.
Therefore, since it is assembled by welding in this manner, sufficient strength can be obtained even when a thin member is used.
As described above, by storing the stator-side member including the winding armature coils 5A and 5B, the Hall sensor H, the drive circuit member D, and the like provided on the stator base 3 inside the cover member 10, power is supplied to the outside of the motor. Since only a pair of power terminals need to be led out from the terminal mounting portion 1d, it can be handled in the same manner as a normal motor, even though it is a brushless motor.
[0009]
Next, referring to FIG. 5, a configuration of a shaft rotation type according to a second embodiment will be described.
Hereinafter, the same members or substantially the same members having the same functions as those of the above-described embodiment are denoted by the same reference numerals, and description thereof may be omitted.
That is, a slightly large-diameter shaft bearing portion 11a protrudes upward in the center of the yoke bracket 11 in a burring shape, and the same sintered oil-impregnated bearing 7 as described above is stored therein. The other parts of the yoke bracket 11 are the same as those of the first embodiment, and the description thereof is omitted.
On the other hand, the tip of the shaft 22 of 0.6 mm is directly press-fitted into the center of the rotor yoke 66, and the eccentric rotor R1 is laser-welded to the rotor yoke 66. The other end of the shaft 66 is pivotally supported by a heat-resistant resin receiving portion integrated with the yoke bracket 11 via a ball bearing B of about 0.3 mm.
Here, instead of the ball bearing B, the base may be formed with a round base.
Since the eccentric rotor R1 is sucked on the yoke bracket side, a thrust washer is unnecessary. Of course, the cover member 100 may be a blind type.
[0010]
【The invention's effect】
Since the present invention is configured as described above, the number of members is reduced with a simple configuration, the drive circuit device can be built in the motor, and the same handling as a normal DC motor can be performed. An extremely thin brushless vibration motor can be provided with sufficient strength while being thin.
[Brief description of the drawings]
FIG. 1 shows a first embodiment of the present invention, and is a cross-sectional plan view of a fixed-shaft, axial-gap, coreless, slotless, brushless vibrating motor.
FIG. 2 is a vertical sectional view taken along the line AA of FIG.
FIG. 3 is a plan view of one member of FIG. 1;
FIG. 4 is a plan view of another member of FIG. 1;
FIG. 5 shows a second embodiment of the present invention, and is a longitudinal sectional view of a shaftless brushless vibration motor of an axial gap type coreless slotless type.
[Explanation of symbols]
1, 11 Yoke bracket 2, 22 Shaft 3 Stator base 4 Heat resistant resin 5A, 5B Air core armature coil 6, 66 Rotor yoke R, R1 Eccentric rotor H Hall sensor D Drive circuit member 7 Bearing 8 Axial air gap type magnet 9 Arc-shaped Eccentric weight 10, 100 Cover member

Claims (5)

Yoke bracket (1, 11), the radial shaft bearing (1a) and detent torque generators arranged radially outward of the shaft bearing as a magnetic portion (1b) and the detent torque generation portion of the center A holding portion (1c) disposed outside, a space (1e) surrounded by these as a non-magnetic portion , and a power supply terminal mounting portion (1d) further integrally and outwardly drawn out from the holding portion. A stator base (3) is attached to the yoke bracket, and two air-core armature coils (single-phased) are connected to the stator base via a center and connected in a single phase. 5A, 5B) is arranged, wherein in a plan view stator base detent torque generating section so as not to overlap these air-core armature coil and each planar view (1b) 1 single Hall sensor on (H) is arranged , A drive circuit member for receiving an output of the sensor (D) is disposed at a position opposite of the sensor, at least the positive and negative power supply terminal portions is the feeding terminal placed consisting of two terminals derived outwardly from the stator base Part ,
The air-core eccentric rotor which is driven by the armature coil (R, R1) comprises a rotor yoke (6, 66) made of a magnetic material, an axial air-gap type magnet having a plurality of magnetic poles arranged in the rotor yoke (8) And an arc-shaped eccentric weight (9) arranged on the rotor yoke at the outer periphery of the magnet, and a central shaft holding portion (6a), and the eccentric rotor rotates via the shafts (2, 22). held freely in the shaft support portion, the cover member (10, 100) is axially gap type driving circuit, characterized in that mounted to the yoke bracket outwards opening is built to cover the eccentric rotor Brushless vibration motor. The base end of the shaft is first fixed to the shaft support portion (1a) by laser welding, and a bearing (7) in which the eccentric rotor is fixed to the center of the rotor yoke is rotatably mounted from the front end of the shaft. A cover member (10) for covering the eccentric rotor is attached to the holding portion of the stator with an opening, and the tip of the shaft is fitted into a concave portion at the center of the cover member, and laser-welded to the cover member from the outside. An axial gap type brushless vibration motor incorporating the drive circuit according to claim 1. In the yoke bracket (11), a bearing (7) for rotatably supporting the shaft (22) is disposed on a shaft support (11a), and the eccentric rotor (R1) is fixed to the center of the rotor yoke on the bearing. 2. An axial gap type brushless vibration with a built-in drive circuit according to claim 1 , wherein the shaft is rotatably mounted via a shaft, and a base end of the shaft is pivotally supported on a stator base side. motor. The axial gap type brushless vibration according to any one of claims 1 to 3 , wherein the axial gap type air core armature coil and the drive circuit member are integrated with the stator base with resin. motor. The yoke brackets (1, 11) are formed of a magnetic metal plate having a thickness of 0.2 mm or less, and the rotor yokes (6, 66) are formed of a magnetic metal plate having a thickness of 0.15 mm or less. An axial gap type brushless vibration motor according to any one of claims 1 to 4 .

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