KR20040038594A - Axial direction gap type brushless motor with built-in drive circuit - Google Patents

Abstract

PURPOSE: An axial gap type brushless motor having a driving circuit unit is provided to reduce the size by reducing the number of components and installing a driving circuit unit in the inside of the motor. CONSTITUTION: A rotor(R) includes an axial air gap type magnet having a plurality of magnetic poles. A shaft(2) is used for supporting the rotor. A yoke bracket(1) is used for supporting the shaft. A stator base(3) is attached to the yoke bracket. An air-core armature coil(5A) is installed in the stator base. A driving circuit is installed on the stator base. A cover member is used for covering the components. The yoke bracket includes a shaft support part, an arm part extended from the shaft support part, and a space part. The arm part and a fixing part are formed with one body. An opening part of the cover member is installed at the fixing part.

Description

Axial air gap type brushless motor with built-in drive circuit member {AXIAL DIRECTION GAP TYPE BRUSHLESS MOTOR WITH BUILT-IN DRIVE CIRCUIT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for a silent notification means of a mobile communication device, or various pickup drive sled motors, and relates to an axial air gap type brushless motor in which a driving circuit member is incorporated.

In the brushless motor, a drive circuit that replaces a brush and a commutator is a prerequisite. All of the conventional structures do not have a built-in drive circuit member, and thus the lead terminal also needs four or more terminals for exterior use. There is a problem that cannot be handled like a normal two-terminal dc motor.

In addition, in a conventional brushless motor, a stator has a plurality of armature coils evenly arranged around its entire circumference, and since drive circuit components require other electronic components such as ICs, they can usually be embedded. It wasn't there.

As a flat axial void type brushless vibration motor, the present applicant has previously proposed a coreless slotless type and does not incorporate a drive circuit member (see Patent Document 1 and Patent Document 2).

A brushless vibration motor having a drive circuit is a cored type and an elliptical type in which a cored drive circuit member formed by winding an armature coil around a plurality of evenly arranged salient poles is arranged on the side of the stator (see Patent Document 3). ).

However, such a size increases in the lateral direction, and the setting has a poor mounting efficiency for the printed wiring board in the SMD system, and also has a corrugated type, so that the thickness is inevitably large, which is not practical.

Therefore, the present applicant proposes to first form a space by removing a part of a plurality of armature coils, including a cored and slotless coreless type, and to arrange a driving circuit member in the space (Patent Document 4). Reference).

(Patent Literature List)

Patent Document 1: Japanese Utility Model Publication Pyeongseong 4 (1992) -137463

Patent Document 2: Japanese Unexamined Patent Publication No. 2002-143767

Patent Document 3: Japanese Unexamined Patent Publication No. 2000-245103

Patent document 4: Unexamined-Japanese-Patent No. 2002-142427 (FIGS. 8-11)

Therefore, the present invention further improves the axial air gap brushless vibration motor shown in FIGS. 8 to 11 of Japanese Patent Laid-Open No. 2002-142427 disclosed in Patent Document 4 to stabilize the stop position of the magnet in a thin and simple configuration. For the detent torque generation, the number of parts is reduced, such as no need for a separate member, and the drive circuit parts can be built in, so that the same handling as a normal DC motor is possible, and each member is thin and sufficient in strength. The aim is to provide a very thin brushless vibration motor.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a first embodiment of the present invention, and is a lateral cut plan view of an axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor.

FIG. 2 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 1.

3 is a plan view of one member of FIG. 1.

4 is a plan view of another member of FIG. 1.

Fig. 5 is a lateral cut plan view of the axial rotational axial air gap type one-hole sensor type coreless slotless brushless motor as a second embodiment of the present invention.

Fig. 6 shows a third embodiment of the present invention, and is a lateral cut plan view of a coreless slotless brushless vibration motor of an axial fixed axial air gap sensorless type.

FIG. 7 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 6.

8 is a plan view of one member of FIG. 6.

9 is a plan view of another member of FIG. 6.

10 is an explanatory diagram of the operation of FIG. 8.

Fig. 11 shows a fourth embodiment of the present invention and is a longitudinal sectional view of a coreless slotless brushless vibration motor of an axial rotational axial pore type sensorless type.

Fig. 12 shows a fifth embodiment of the present invention, and is a lateral cut plan view of an axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor.

FIG. 13 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 12.

14 is a plan view of one member of FIG. 12.

Fig. 15 is a longitudinal sectional view of the axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor as a sixth embodiment of the present invention.

Fig. 16 shows a seventh embodiment of the present invention and is a lateral cut plan view of a coreless slotless brushless vibration motor of an axial fixed axial air gap sensorless type.

17 is a longitudinal cross-sectional view taken along the line AA ′ of FIG. 16.

Fig. 18 shows an eighth embodiment of the present invention, and is a longitudinal sectional view of a coreless slotless brushless vibration motor of an axial rotational axial pore type sensorless type.

19 is a longitudinal sectional view showing a ninth embodiment of the present invention as a modification of FIG. 15.

20 is a longitudinal cross-sectional view showing a tenth embodiment of the present invention as a modification of FIG. 19.

Fig. 21 shows an eleventh embodiment of the present invention and is a longitudinal cross-sectional view of a geared brushless motor incorporating a gear in a rotor.

* Description of the symbols for the main parts of the drawings *

1, 11: yoke bracket

2: axis

3: stator base

4: heat resistant resin

5A, 5B: Concentric Armature Coil

6, 66: rotor yoke

R, R1, R3, R4: Eccentric Rotor

H: Hall sensor

D: drive circuit member

7: sintered bearing

8, 88: axial air gap magnet

9: bow-shaped eccentric weight

10: cover member

As an invention which solves the said subject, like the invention shown in Claim 1, the rotor arrange | positioned the axial gap-type magnet which has a some magnetic pole, the shaft which supports this rotor, and the yoke which supports this shaft The stator base installed in addition to the yoke bracket, the air core armature coil disposed on the stator base, and the air core armature coil so as not to overlap with each other in plan view, and to the stator base within the placement thickness of the air core armature coil. And a cover member covering them, wherein the yoke bracket has a shaft support at its center, and a space portion is formed between the arm portion extending radially from the shaft support and the arm portion. The fixed part is formed integrally with the said arm part, and it can comprise by providing the opening part of the cover in this fixed part.

In this way, the drive circuit member can be easily incorporated, the feed terminal can also be made into two terminals of ±, and the thickness of the drive circuit member can be ignored, so that the thickness can be reduced.

Specifically, as in the invention shown in claims 2 and 3, the air core armature coil is connected in two single phases, and the drive circuit device is composed of one Hall sensor and a drive circuit member that receives the output of the sensor. At least a part of the drive circuit member is disposed in the space portion of the yoke bracket, and a rotor yoke is attached to the axial void magnet, and the rotor yoke is supported on the shaft through the shaft support, and furthermore, the yoke bracket And part of the stator base protrude laterally from the cover member to form a feed terminal portion, wherein the yoke bracket is made of a magnetic body or a weak magnetic body, and the axial air gap magnet disposed on the rotor yoke is It is configured to generate detent torque in the arm part of the yoke bracket, or the cover and the yoke bracket are installed. This means that by laser welding, it is preferable that the eccentric weight in a plan view is formed in a bow shape provided by laser welding from the outside of the axial air gap-type magnet.

In this way, a brushless motor of a one-hole sensor type can be constituted, and since the cover and the yoke bracket are laser welded, deformation is unlikely to occur, and the feed terminal can be protected using the yoke bracket.

Further, in the shaft fixing method, as in the inventions shown in claims 4 and 5, the yoke bracket has a thickness of 0.2 mm or less, and the base end of the shaft is fixed at the center thereof, and resin is integrated at least in the space portion. The eccentric rotor has a bearing disposed in the shaft support of the rotor yoke, and is rotatably mounted to the shaft through the bearing, and the tip of the shaft is fitted into the recess of the center of the cover member. Should have reinforcing ribs on the shaft support.

In this case, even if there is an impact in the radial direction, since the shock can be picked up by the cover, a narrow width can be adopted. Since both the yoke bracket and the rotor yoke are thin, they can be made very thin as a motor. In addition, by welding the tip of the shaft, deformation of the cover and the bracket is also impossible, and the strength can be maintained even in the case of a thin rotor yoke.

In the axial rotation method, as in the invention shown in claim 6, the tip of the shaft is welded to the center of the rotor yoke, and a bearing portion for rotatably supporting the shaft is disposed at the center of the stator base. It may be pivotally supported on the stator base side.

In this way, the slide loss can be reduced because the pivot ends of the shaft are supported.

Further, in the sensorless type, as in the inventions shown in claims 7, 8, 9 and 10, the rotor yoke is added to the axial air gap magnet while the axial air gap magnet having a plurality of magnetic poles is arranged. A three-phase comprising an installed rotor, a shaft supporting the rotor, a yoke bracket supporting the shaft, a stator base provided in addition to the yoke bracket, and at least three winding concentric armature coils disposed on the stator base And a sensorless drive circuit member disposed on the stator base so as not to overlap with the winding air core armature coil in plan view, respectively, and a cover member for covering them, wherein the arm portion of the yoke bracket is centered. Radially circumferentially so as to be within the thickness of these members between the air core armature coil and the drive circuit member And a part of the yoke bracket and a part of the stator base are laterally protruded from the cover member to form a feed terminal part, and an opening of the cover member is provided in the fixing part. And the means for installing the yoke bracket is by laser welding, and the eccentric weight is formed in the shape of a bow when viewed in a plane and installed by laser welding on the outside of the axial void magnet, and the rotor yoke has a thickness It is made of a magnetic material of 0.15 or less, and there is a plurality of reinforcing ribs in the shaft support, wherein the three-phase air core armature coil and the air core armature coil formed in one layer on both sides of the stator base so as to overlap with each of the winding type air core coil The stator bezel on the side opposite the side on which the drive circuit member is disposed It consists of an air core armature coil formed in one layer on one side of a rice, and it is good to connect with each said winding type air core armature coil in series.

In this way, the sensorless drive circuit member can be easily built-in, the feeder terminal can also be made into two terminals of ±, and the thickness of the drive circuit device can be ignored. In addition, the number of air core armature coils can be easily detected, the counter-voltage can be easily detected, and the characteristics can be improved.

Even in the case of the sensorless type, specifically, the base end of the shaft is fixed to the center of the yoke bracket as in the invention shown in claims 11 and 12, and the eccentric rotor has a bearing disposed at the shaft support of the rotor yoke. The shaft is fixedly mounted to the shaft through the bearing, and the tip of the shaft is fixed to the shaft in the center of the cover member, or the tip is welded to the shaft support of the rotor yoke. The bearing portion rotatably supported is disposed at the center of the stator base, and the base end of the shaft can be applied to the shaft fixed type in which the shaft is pivotally supported on the stator base side.

As another means for solving the problem, as in the invention shown in claim 13, a rotor provided with an axial gap magnet having a plurality of magnetic poles, and a stator for driving the rotor through the axial gap, are provided. An axial air gap brushless motor with a cover, wherein the rotor can be achieved by using the inner diameter side of the axial air gap magnet as an axial support portion.

In this way, since the magnet as the fixing means uses a dead space that cannot be magnetized in the inner diameter portion, it is not necessary to think about a characteristic problem, and it is possible to omit the yoke, thus contributing to thinning. .

Further, in the shaft fixing method, as in the invention shown in claims 14 and 15, a shaft is fixedly attached to the stator, the axial void magnet is formed of sintered metal, and means for using the inner diameter side as the shaft support portion The sintered bearing is welded to the inner diameter side of the axial void magnet, and the sintered bearing is protruded axially from the axial void magnet, and the outer diameter of the protruding portion and the inner diameter side of the magnet are welded. It is good to weld.

In this way, since the weld part uses the dead space, the thickness of the motor is not sacrificed.

In the axial rotation method, as in the invention shown in Claims 16 and 17, a means is fixedly attached to the stator, and means for using the inner diameter side of the axial void magnet as an axial support portion welds the shaft to the inner diameter side. It is preferable that a magnet locking means is provided on the shaft, and the magnet is fixedly attached to the shaft through the magnet locking means.

By doing in this way, it can be set as the shaft rotation type which becomes easy to couple | bond a shaft and a magnet.

Here, too, as in the invention shown in claim 18, if a thin yoke plate is provided at least on the opposite side of the stator of the axial void magnet, a magnetic circuit can be formed.

As shown in claim 19, the rotor is made of a resin, and a metal member is adhered to the inner diameter of the resin in the axial gap magnet, and the rotor may be axially supported through the metal member. Do.

In this way, the magnetization curve can be made sine wave by the isotropic rare earth resin magnet, and the adsorption force to the facing yoke bracket can be controlled.

These are the rotor of any one of Claims 13-18, the bracket which rotatably supports this rotor through an axis | shaft, and the stator base provided in addition to this bracket, as shown to Claim 20, 21, 22, and 23. The thickness of the air core armature coils is arranged in a plurality of air core armature coils arranged on the stator base and in a space in which the air core armature coils are not arranged in a placement area where the outer core diameter of the air core arm coils is circled. A drive circuit member is disposed on the stator base so that the bracket has a shaft support at its center, an arm portion extending radially following the shaft support portion, and an integral fixing portion on the arm portion. A part of the driving circuit member is to be stored in the space part surrounded by the fixing part in plan view. Since the thickness of the driving circuit member can be negligible, it can contribute to thinning, and is made of copper tungsten alloy as each member, and at least the bow-shaped eccentric weight having a welding margin on the opposite side of the stator has the axial air gap. The eccentric rotor can be easily configured by being integrated by welding at the welding clearance portion on at least the outer side of the magnet, and the thin yoke plate is at least partially hanged on the outer diameter of the magnet. The thermal effect on the magnet is alleviated, and the hanging portion has an outwardly bent portion at the hanged tip, and the arrangement of the bow-shaped weight is convenient when the engaging portion is combined with the eccentric weight.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a first embodiment of the present invention, and is a lateral cut plan view of an axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor.

FIG. 2 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 1.

3 is a plan view of one member of FIG. 1.

4 is a plan view of another member of FIG. 1.

Fig. 5 is a lateral cut plan view of the axial rotational axial air gap type one-hole sensor type coreless slotless brushless motor as a second embodiment of the present invention.

Fig. 6 shows a third embodiment of the present invention, and is a lateral cut plan view of a coreless slotless brushless vibration motor of an axial fixed axial air gap sensorless type.

FIG. 7 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 6.

8 is a plan view of one member of FIG. 6.

9 is a plan view of another member of FIG. 6.

10 is an explanatory diagram of the operation of FIG. 8.

Fig. 11 shows a fourth embodiment of the present invention and is a longitudinal sectional view of a coreless slotless brushless vibration motor of an axial rotational axial pore type sensorless type.

Fig. 12 shows a fifth embodiment of the present invention, and is a lateral cut plan view of an axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor.

FIG. 13 is a longitudinal cross-sectional view taken along line AA ′ of FIG. 12.

14 is a plan view of one member of FIG. 12.

Fig. 15 is a longitudinal sectional view of the axial fixed axial air gap type one-hole sensor type coreless slotless brushless motor as a sixth embodiment of the present invention.

Fig. 16 shows a seventh embodiment of the present invention and is a lateral cut plan view of a coreless slotless brushless vibration motor of an axial fixed axial air gap sensorless type.

17 is a longitudinal cross-sectional view taken along the line AA ′ of FIG. 16.

Fig. 18 shows an eighth embodiment of the present invention, and is a longitudinal sectional view of a coreless slotless brushless vibration motor of an axial rotational axial pore type sensorless type.

19 is a longitudinal sectional view showing a ninth embodiment of the present invention as a modification of FIG. 15.

20 is a longitudinal cross-sectional view showing a tenth embodiment of the present invention as a modification of FIG. 19.

Fig. 21 shows an eleventh embodiment of the present invention and is a longitudinal cross-sectional view of a geared brushless motor incorporating a gear in a rotor.

EMBODIMENT OF THE INVENTION Hereinafter, it demonstrates based on each embodiment which shows the structure of this invention.

1 and 2 show a hall sensor type brushless vibration motor of the axial fixed axial air gap type coreless slotless type of the first embodiment of the present invention, that is, the yoke bracket 1 is weaker than the iron plate. The magnetic stainless steel plate has a thickness of 0.15 mm to 0.2 mm, and has a shaft support part 1a inserted in the center in a burring process. Furthermore, the yoke bracket is an arm portion made of a magnetic body receiving magnetic fields of three axial field magnets described later, which are formed at an opening angle of about 120 degrees in the radial direction as shown in FIG. 1b) and a radially extending portion having a fixed portion 1c having a ring-shaped reinforcement, and part of the fixed portion further protrudes in a radial direction to form a feed terminal placing portion 1d. The yoke bracket 1 constitutes a nonmagnetic space portion 1e between the detent torque generating portions 1b in order to stop the magnetic pole of the axial field magnet, which will be described later, at a specific position.

In the upper surface of the yoke bracket 1 configured as described above, a narrow shaft 2 of 0.5 mm is pressed into the shaft support portion 1a at the base end, and a flexible printed circuit board stator base 3 is placed around the shaft support portion 1a. Furthermore, the yoke bracket 1 is integrated with a heat resistant resin 4 that can withstand reflow soldering such as liquid crystal, polyphenylene sulfide, and the like so that the yoke bracket 1 is interbone. The heat resistant resin is also filled in the nonmagnetic space portion 1e, reinforces the yoke bracket 1, and blocks the space portion 1e. On the stator base 3, two winding core core armature coils 5A, 5B are placed facing each other and connected in series so as to be in a single phase.

Between these winding-type air core armature coils 5A and 5B, a drive circuit device composed of one Hall sensor H and an IC-driven drive circuit member D is disposed in the stator base.

Here, the positional relationship between the detent torque generator 1b and the single-phase air core armature coil is set in accordance with the magnetic poles of the magnet described later, and the shape of the detent torque generator 1b is When stopped by the magnetic force of the magnet, it is preferable that the minimum stabilizing torque is obtained in every posture.

In addition, when the magnetic attraction force of the detent torque generating unit may increase, the bracket may be formed of a nonmagnetic material to perform thin magnetic plating.

Therefore, these stator members do not overlap when an air core armature coil etc. are seen in a plane, and can be comprised thin. Considering the space portion 1e as necessary, the position where the drive circuit member D of the stator base 3 is placed may be set in the space portion 1e instead of the detent torque generating portion 1b. have.

In this case, since the stator base 3 made of the flexible printed wiring board runs to this space part, the thickness of the stator base 3 in this part can be ignored. On the other hand, of course, the hall sensor H is disposed on the detent torque generating section 1b for the output bias.

Such a configuration is the same as that shown in FIG. 19 described later.

Here, a part of the heat resistant resin 4 is stood as guides 4a and 4b, and the air core armature coils 5A and 5B are mounted using the guides 4a and 4b. You may integrally shape with resin 4 including another member. Therefore, even if the yoke bracket 1 is thin, the integrated member becomes interbone and the strength is reinforced. In this way, the entire reinforcement on the stator side is possible.

Here, a part of the heat resistant resin 4 is stood as guides 4a and 4b, and the air core armature coils 5A and 5B are mounted using the guides 4a and 4b. It may be molded integrally, including.

On the other hand, the eccentric rotor R rotatably mounted on the shaft, as shown in Figs. 2 and 4, has a sintered bearing 7 in a bearing fixing portion 6a of a burring type in the center. Three points of the pressurized rotor yoke 6 of about 0.1 mm, the axial void magnet 8 adhered to the lower surface, and the rotor yoke 6 of the outer circumference of the magnet 8. In the laser spot welded bow-shaped weight (9).

Here, in the rotor yoke 6, reinforcing ribs 6b are formed radially from the bearing fixing part 6a using dead space in the thickness direction to prevent deformation during impact such as falling. In the figure, reference numeral 6c denotes a tongue which is stretched for reinforcement at the same time as the magnet 8 is positioned. Since the magnet 8 is six-pole magnetized and its driving principle is known, the description thereof is omitted.

The eccentric rotor R thus constructed is rotatably mounted to the shaft 2 via thrust washer S1 laminated at least in two sheets to reduce brake loss. The shallow cap-shaped cover member 10 is covered, and the tip of the shaft is fitted through the thrust washer S2 to the burring hole 10a formed in the center of the cover member 10. Here, the burring hole is narrower than the shaft diameter so that the tip of the shaft 2 does not protrude so that the tip is laser welded to the cover member 10 to prevent deformation, and at the same time, the cover member. The opening of 10 is provided in the fixing portion 1c of the yoke bracket 1 by laser spot welding.

Therefore, since it is provided by welding in this way, even if a thin member is used, intensity | strength can fully be obtained.

Thus, by storing the stator side member made of the winding armature coils 5A and 5B provided on the stator base 3, the Hall sensor H, the drive circuit member D, and the like, inside the cover member 10. Since a pair of power supply terminals need only be led out from the power supply terminal placing part 1d to the outside of a motor, it can be handled similarly to a normal motor although it is a brushless motor.

Next, in FIG. 5, the structure of the axial rotation type which is 2nd Embodiment is demonstrated.

Hereinafter, the same code | symbol is attached | subjected about the member same as the said embodiment or the substantially same member which has the same function, and the description may be abbreviate | omitted.

That is, the yoke bracket 11 has the slightly larger diameter shaft support part 11a protruding upwards in the form of a burring process, and the same sintered bearing 7 as mentioned above is stored here. Since other parts of the yoke bracket 11 are the same as in the first embodiment, the description thereof is omitted.

On the other hand, as for the eccentric rotor R1, the tip of the shaft 22 of 0.6 mm is directly press-fitted to the center of the rotor yoke 66 at this time, and the laser spot welding is carried out to the rotor yoke 66 further. The other end of this shaft 66 is pivotally supported by the receiving part of the heat resistant resin integrated with the yoke bracket 11 via the ball bearing B of about 0.3 mm.

Here, the base may be rounded on the shaft instead of the ball bearing (B).

Since the eccentric rotor R1 is sucked to the yoke bracket side, the thrust washer is not necessary. Naturally, the cover member 100 may be a blind type.

Hereinafter, the 3rd Embodiment of this invention shown in FIG. 6, FIG. 7 is demonstrated.

Here, the coreless slotless brushless vibration motor of the axially fixed axial air gap sensorless type, that is, the yoke bracket 21 is composed of about 0.2 mm thick by a stainless steel plate having weak magnetic properties, A radius is passed between the shaft support portion 1a in which a 0.5 mm narrow shaft 2 is press-fitted at the proximal end and inserted into the stator base 3 in the radial direction as shown in FIG. 8. The arm portion 21b extending in the direction and a ring-shaped fixing portion 1c having integral reinforcement to the arm portion 21b, wherein a part of the fixing portion protrudes further in the radial direction to feed the power supply terminal placing portion. (1d).

In the lower part of the yoke bracket 1 comprised in this way, the stator base 3 which consists of a flexible printed wiring board or a glass cross epoxy board is attached. The stator base 3 includes three-phase armature coils, that is, three winding concentric armature coils 5A, 5B, and 5C, and six printed wiring concentric armature coils when viewed in a plane connected in series to these concentric armature coils. 5a, 5b ... 5f) are formed.

Here, instead of the printed wiring coil, a thin, for example, 0.05 mm insulated copper wire having a diameter of 0.05 mm may be attached to the sheet coated on the surface while being wound and attached in one layer.

On the opposite side across the center of these winding core core armature coils 5A, 5B, and 5C, a sensorless IC-driven drive circuit member D and its accessories are arranged.

Naturally, since the wiring pattern of these electronic members is required, the printed wiring concentric armature coils 5a, 5b, 5c on the electronic member arrangement side are formed only on the back side, and the surface avoids the wiring pattern of the drive circuit member to start winding. In this way, the terminal withdrawal pattern is about as much as possible.

Since this connection relationship becomes complicated when it is shown as a structural diagram, it connects like operation explanatory drawing which described the connection state as shown in FIG. 10, and the description is abbreviate | omitted.

And they are integrated with the heat resistant resin 4 which can withstand reflow soldering, such as a liquid crystal and polyphenylene sulfide, so that the arm part 21b of the said yoke bracket 1 may become bone.

Therefore, these stator members do not overlap in plan view, and can be comprised thin.

Although not shown in particular, the said heat resistant resin 4 may raise the said air core armature coil placement guide, and may place the said air core armature coil on this guide instead of integral molding.

On the other hand, the eccentric rotor R2, which is rotatably mounted on the shaft, has a thin rotor yoke of about 0.1 mm in which a sintered bearing 7 is press-fitted into a bearing fixing portion 6a of a burring type center installed at the center. (6), laser spot welding at three points on the axial air gap magnet 8 adhered to the lower surface, and the rotor yoke 6 as shown in FIG. 9 on the outer circumference of the magnet 8; It consists of the (Y) bow-shaped weight 9.

Here, in the rotor yoke 6, reinforcing ribs 6b are formed radially from the shaft fixing portion 6a using dead space in the thickness direction to prevent deformation during impact such as falling. In the figure, reference numeral 6c denotes a tongue that is arranged for reinforcement at the same time as the magnet 8 is positioned. The magnet 8 is six-pole magnetized, and the eccentric rotor R2 thus configured is rotatably mounted to the shaft 2 through a thrust washer S1 laminated in at least two sheets to reduce brake loss. do. Subsequently, a cover member 10 made of a stainless steel material which is thinner than nonmagnetic or magnetically weaker is covered, and a thrust washer S2 is formed in the burring hole 10a formed at the center of the cover member 10 at the tip of the shaft. Through). Here, the burring hole is narrower than the shaft diameter so that the tip of the shaft 2 does not protrude and the tip portion is laser-welded L1 to the cover member 10 to prevent deformation. The opening of the cover member is provided in the fixing portion 1c of the yoke bracket 1 by laser spot welding L2.

Therefore, since it is provided by welding in this way, even if a thin member is used, intensity | strength can fully be obtained.

As the driving principle of the sensorless flat motor configured as described above, a known one for detecting and driving the direction of counter electromotive force of the air core armature coil itself is employed, and thus the description thereof is omitted.

Next, in FIG. 11, the structure of an axial rotation type | mold is demonstrated as 4th Embodiment which becomes a deformation | transformation of the said 2nd Embodiment.

Hereinafter, the same code | symbol is attached | subjected about the same member or substantially the same member which has the same function as the said embodiment, and the description may be abbreviate | omitted.

That is, the yoke bracket 31 has a slightly larger diameter shaft support portion 11a protruding upward in the form of a burring process, and the same sintered bearing 7 as described above is stored therein. Since other parts of the yoke bracket 31 are the same as in the first embodiment, the description thereof will be omitted.

On the other hand, as for the eccentric rotor R3, the tip of the shaft 22 of 0.6 mm is directly press-fitted to the center of the rotor yoke 66 at this time, and the laser spot is welded to the rotor yoke 66. The other end of this shaft 22 is pivotally supported by the receiving part of the heat resistant resin 44 integrated with the yoke bracket 11 via the ball bearing B of about 0.3 mm.

Here, the base may be rounded on the shaft instead of the ball bearing (B).

Since the eccentric rotor R3 is attracted to the yoke bracket side, the thrust washer is not necessary. Naturally, the cover member 100 may be a blind type.

12 and 13 show a fifth embodiment of the present invention, which is an axially fixed axial air gap type one-hole sensor type coreless slotless brushless motor.

That is, the yoke bracket 1, as shown in Fig. 14, is made of a thin plate having a thickness of 0.15 mm to 0.2 mm by a stainless steel plate having a weaker magnetic force than an iron plate, and is axially supported by a burring form in the center 1a. There is). Furthermore, the yoke bracket 1 is an arm part made of a magnetic body subjected to magnetic fields of three axial field magnets described later, which are formed at an opening angle of about 120 degrees in the radial direction, and the detent torque generating section 1b and more. It extends in the radial direction and has the fixing part 1c which has ring-shaped reinforcement, and part of this fixing part protrudes further radially, and is set as the feed terminal mounting part 1d. The yoke bracket 1 constitutes a nonmagnetic space portion 1e between the detent torque generating sections 1b in order to stop the magnetic pole of the axial field magnet, which will be described later, at a specific position.

In the upper surface of the yoke bracket 1 configured as described above, a narrow shaft 2 of 0.5 mm is pressed into the shaft support portion 1a at the base end, and a flexible printed circuit board stator base 3 is placed around the shaft support portion 1a. Furthermore, the yoke bracket 1 is integrated with a heat resistant resin 4 that can withstand reflow soldering such as liquid crystal, polyphenylene sulfide, and the like so that the yoke bracket 1 is interbone. The heat resistant resin is also filled in the nonmagnetic space portion 1e, reinforcing the yoke bracket 1, and blocking the space portion 1e. On the stator base 3, two winding core core armature coils 5A, 5B are placed facing each other and connected in series so as to be in a single phase.

Between these winding-type air core armature coils 5A and 5B, a drive circuit device composed of one Hall sensor H and an IC-driven drive circuit member D is disposed in the stator base.

Here, the positional relationship between the detent torque generator 1b and the single-phase air core armature coil is set in accordance with the magnetic poles of the magnet described later, and the shape of the detent torque generator 1b is When stopped by the magnet's magnetic force, it is good to set so that the minimum static torque is obtained in every posture.

These stator members do not overlap when the air core armature coil or the like is viewed in a plane, and can be configured in a thin shape.

On the other hand, if necessary, the driving circuit member D is further miniaturized and the position where the driving circuit member of the stator base 3 is placed is not the detent torque generating portion 1b but the space portion, as indicated by the imaginary line. By setting to (1e), since the stator base 3 made of a flexible printed wiring board runs to this space part, the thickness of the stator base 3 of this part can be ignored. Here, the hall sensor H is naturally set to be above the detent torque generator 1b in order to obtain a bias magnetic field.

This configuration is as shown in FIG. 19 described later.

Here, a part of the heat-resistant resin 4 is standing as guides 4a and 4b, and the air core armature coils 5A and 5B are mounted using the guides 4a and 4b. It is also possible to integrally mold with the resin 4 including other members. Therefore, even if the yoke bracket 1 is thin, the integrated member becomes interbone and the strength is reinforced. In this way, the entire reinforcement on the stator side is possible.

On the other hand, in the eccentric rotor R4 rotatably mounted on the shaft, as shown in Fig. 14, the sintered bearing 7 is attached to the inner diameter side of the axial void magnet 8 by laser welding. And the bow-shaped weight 9 laser-welded to the rotor yoke 6 on the rotor yoke 6 at the outer circumference of the magnet 8. Naturally, the inner diameter side of the magnet cannot magnetize even the laser welded portion due to the structure of the magnetizing yoke. That is, since the magnetized dead space is used for welding, the characteristic does not deteriorate.

Here, the axial air gap magnet 8 is subjected to magnetic plating such as pure iron on its surface, and the rotor yoke is removed here.

Therefore, the thickness can be as thin as the rotor yoke.

The magnet 8 is six-pole magnetized alternately N and S here, and the driving principle thereof is well known, and thus description thereof is omitted.

The eccentric rotor R4 thus constructed is rotatably mounted to the shaft 2 via a thrust washer S1 stacked on at least two sheets to reduce brake loss. Subsequently, a shallow cap-shaped cover member 10 made of a thin nonmagnetic stainless steel is covered, and the thrust washer S2 is attached to the burring hole 10a formed at the center of the cover member 10 at the tip of the shaft. It is fitted through. Here, the burring hole has a tip that is narrower than the shaft diameter, and the tip of the shaft 2 does not protrude so that this tip portion is laser-welded to the cover member 10 to prevent deformation during impact. At the same time, the opening of the cover member 10 is provided in the fixing portion 1c of the yoke bracket 1 by laser spot welding.

Therefore, since it is provided by welding in this way, even if a thin member is used, intensity | strength can fully be obtained.

Thus, by storing the stator side member made of the winding armature coils 5A and 5B provided on the stator base 3, the Hall sensor H, the drive circuit member D, and the like, inside the cover member 10. Since a pair of power supply terminals need only be led out from the power supply terminal placing part 1d to the outside of a motor, it can be handled similarly to a normal motor although it is a brushless motor. If it is made of nonmagnetic stainless steel as a cover, since it has a heat insulation effect, it can withstand reflow.

Next, although FIG. 15 demonstrates the said 5th Embodiment, the same code | symbol is attached | subjected about the member same as the said embodiment or the substantially same member which has the same function, and the description may be abbreviate | omitted.

Here, the eccentric rotor R5 is provided by attaching a thin yoke plate 6 having a thickness of about 0.05 mm to the upper surface of the axial cavity magnet 8, and of course, the yoke plate 6 has strength. It is not just to secure the circuit, but simply to construct a magnetic circuit.

Accordingly, the inner diameter side of the magnet is welded to the bearing.

In this case, since the leakage magnetic flux to the upper direction of the axial void magnet 8 becomes small, the cover may be made of stainless steel which is usually slightly magnetic.

16 and 17 use the yoke bracket 21 shown in FIG. 8 as the coreless slotless brushless vibration motor of the axially fixed axial air gap sensorless type.

The fixing portion 1c is formed in a state of being lowered in one step with respect to the shaft support portion 1a and the arm portion 21b in a downward direction, and that is, the lower portion of the yoke bracket 21, that is, the shaft support portion 1a and the arm portion ( Under the side of 21b), the stator base 3 which consists of a flexible printed wiring board or a glass cross epoxy board is attached.

Moreover, the feed terminal part in which one part of the stator base 3 protrudes is fixed to the upper side of the feed terminal mounting part 1d using the step | step difference of the fixing part 1c and the axial support part 21a.

The stator base 3 includes three-phase armature coils, that is, three winding concentric armature coils 5A, 5B, and 5C, and six printed wiring concentric armature coils when viewed in a plane connected in series to these concentric armature coils. 5a, 5b, ... 5f) are equally formed.

In the winding type air core armature coils 5A, 5B, and 5C, one opening angle is disposed within 180 degrees, and three out of six printed wiring type air core armature coils 5a, 5b, and 5c are arranged in the same position. .

Here, instead of the printed wiring coil, it may be formed by attaching a thin, for example, 0.05 mm insulated copper wire having a diameter of about 0.05 mm to which the adhesive is applied to the surface while winding it in one layer.

On the stator base 3, between the winding concentric armature coils 5A, 5B and 5C, the remaining three printed wiring type concentric armature coils 5d and 5e so as to be between the arm portions 21b. 5f), the sensor circuit IC drive circuit member D and its accessories are arranged. That is, the stator base 3 is located below the shaft support portion 1a and the arm portion 21b of the yoke bracket 1, and the shaft support portion 1a and the arm portion 21b are the winding concentric armature coils 5A, 5B, 5C) and the drive circuit member D, and their attached parts and the like, are provided within the thickness thereof.

Naturally, since the connection pattern of these drive circuit members is required, the printed wiring concentric armature coils 5a, 5b, 5c on the side of this drive circuit member arrangement are formed only on the back side, and the surface avoids the connection pattern of the drive circuit member. Start the winding and make it as much as the terminal withdrawal pattern.

And they are integrated with the heat resistant resin 4 which can withstand reflow soldering, such as a liquid crystal and polyphenylene sulfide, so that the arm part 21b of the said yoke bracket 1 may become bone.

Therefore, the wound air core armature coil, the drive circuit member, the arm portion 21b, and the like arranged on the stator base 3 can be made thin because they do not overlap in plan view except for printed wiring. Moreover, the strength of the stator part centering on the stator base 3 can be made strong by resin-molding the arm part 21b integrally.

Although not shown in particular, the said heat resistant resin 4 may raise the said air core armature coil placement guide, and may place the said air core armature coil on this guide instead of integral molding.

Thereafter, a flat cup-shaped cover member 10 made of a stainless steel material, which is thinner than nonmagnetic or magnetic, is covered with a thrust in the burring hole 10a formed at the center of the cover member 10. It is fitted through the washer (S2). Here, the burring hole is narrower than the shaft diameter, and the tip of the shaft 2 is not protruded, so that the tip portion is laser welded to the cover member 10 to prevent deformation.

The opening of the cover member 10 is provided in the ring-shaped fixing portion 1c of the yoke bracket 1 by laser spot welding.

Thus, the vibration motor provided by welding can fully acquire the intensity | strength even if a thin member is used.

As the driving principle of the sensorless flat motor configured as described above, a known one which detects and drives the direction of counter electromotive force of the air core armature coil itself is employed. As shown in FIG.

Next, the structure of the axial rotation type which is 7th Embodiment is demonstrated in FIG.

Also here, about the member similar to the said embodiment or the substantially same member which has the same function, the same code | symbol may be attached | subjected and the description may be abbreviate | omitted.

That is, compared with 1st Embodiment, the shaft support part 11a of a slightly larger diameter protrudes upwards in the burring process form in the center of the yoke bracket 31, and the sintering bearing 7 is stored here. Since the other part of the yoke bracket 31 is the same as that of the said 1st Embodiment, the description is abbreviate | omitted.

Here, the stator is a modified example of Figs. 6 and 11, which consists of winding-type concentric armature coils of different thickness, that is, thick concentric armature coils 5A, 5B and 5C in a flexible printed wiring board (not shown). Instead of the printed wiring concentric armature coils 5e, 5d and 5f, a thin concentric armature coil formed by a winding is disposed, and the sensorless IC drive circuit member D is formed so as to overlap with the thin concentric armature coil. The accessory parts are arranged.

On the other hand, in the eccentric rotor R6, the tip of the shaft is welded to the inner diameter side of the magnet 8 as described above through the eyelet tube 2a.

Here, although the eyelet-shaped tube 2a is press-fitted to the shaft, as a positioning, the main part of welding is in the inner diameter side of a shaft and a magnet. The other end of this shaft 22 is pivotally supported by the receiving part of the heat resistant resin integrated with the yoke bracket 31 via the ball bearing B of about 0.3 mm.

Here, the base may be rounded on the shaft instead of the ball bearing (B).

Since the eccentric rotor R6 is attracted to the yoke bracket side, the thrust washer is not necessary. Naturally, the cover member 100 may be a blind type here.

FIG. 19 shows a ninth embodiment as a modification of FIG. 15. The thin yoke plate 66 constituting the eccentric rotor R7 is made of magnetic stainless steel having a thickness of about 0.1 mm. The outer diameter part 6a hangs on the outer diameter part of the magnet 8, and the eccentric weight 9 is integrated by welding through this outer diameter part 6a. This mitigates the thermal effect on the magnet.

Moreover, as this deformation | transformation, the magnet may adhere | attach and store in the thin yoke plate.

Here, since the flexible stator base 3 on which the drive circuit member (hole IC) is placed is accommodated in the space portion 1e of the bracket, the thickness of the stator base of this portion can be neglected and the thickness is reduced. Can contribute to Since the other member is the same as that of embodiment mentioned above, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

Fig. 20 shows a tenth embodiment of the present invention as an application example of Fig. 19, wherein the axial void magnet 88 is made of a rare earth magnet made of resin, and the metal member 88a is adhered to the inner diameter. The shaft is held by welding to the sintered bearing 7 through the metal member 88a.

When such a magnet made of resin is isotropic, for example, sinusoidal magnetization can be obtained, and therefore, the adsorption on the bracket side can be controlled.

In addition, even if it is made of resin, welding can be fixed to the bearing.

Fig. 21 shows an eleventh embodiment of the present invention, in which a gear G is integrally formed with a rotary rotor R7 to form a geared motor. Here, the outer periphery of the yoke 66 constituting the magnet of the magnet is slightly extended in the radial direction, and this part is made into the gear G, and the gear is connected to the side of the cover 100 present in the gear G. The window 100a is provided. On the other hand, if the gear G is too thin, it can also be integrated as a resin gear including this gear part.

In this way, since the thickness of a gear can be ignored, a thin shape can be maintained.

The other structure is the same as that of embodiment mentioned above, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

In addition, the said embodiment is only what disclosed the best thing which implements the technical idea of this invention, and this invention can take various other embodiment without deviating from the technical idea and a characteristic. Therefore, the above embodiment is merely an example and should not be interpreted limitedly. The technical scope of the present invention is indicated by the claims, and is not limited to the specification text.

Since the present invention is configured as described above, the number of members can be reduced with a simple configuration, and the drive circuit device can be incorporated inside the motor, so that the feeder terminal can also be made of two terminals of ±. By enabling the handling, each member can be made thin and sufficient in strength to provide a very thin brushless vibration motor.

Claims (30)

A rotor disposed with an axial air gap magnet having a plurality of magnetic poles, an axis supporting the rotor, a yoke bracket supporting the shaft, a stator base provided in addition to the yoke bracket, and disposed on the stator base The air core armature coil, a drive circuit device disposed on the stator base so as not to overlap with the air core armature coil in plan view, and within the arrangement thickness of the air core armature coil, and a cover member covering them, the yoke bracket is provided. A space portion is formed between the axial support portion, the arm portion extending radially from the axial support portion, and the arm portion, and furthermore, a fixing portion is formed integrally with the arm portion, and the opening portion of the cover is formed in the fixing portion. An axial air gap brushless motor with a built-in drive circuit member, characterized in that the installation. The method of claim 1, wherein the air core armature coil is connected in two single phases, the drive circuit device comprises one Hall sensor and a drive circuit member that receives the output of the sensor, at least a part of the drive circuit member Disposed in the space portion of the yoke bracket, the rotor yoke is additionally installed in the axial void magnet, the rotor yoke is supported on the shaft through an axial support, and furthermore a portion of the yoke bracket and part of the stator base Protrudes laterally from the cover member to form a feed terminal portion, wherein the yoke bracket is made of a magnetic material or a weak magnetic material, and an axial air gap magnet disposed on the rotor yoke is detent in the arm portion of the yoke bracket. Axial air gap brushless with built-in drive circuit member, characterized in that configured to generate torque Emitter. The method of claim 2, wherein the means for installing the cover and the yoke bracket is by laser welding, wherein the eccentric weight is formed in the shape of a bow when viewed in a plane, and is installed by laser welding on the outside of the axial void magnet. An axial air gap brushless motor with a built-in drive circuit member. 3. The yoke bracket has a thickness of 0.2 mm or less and the base end of the shaft is fixed at the center thereof, and resin is integrated at least in the space portion, so that the eccentric rotor has a bearing disposed at the shaft support of the rotor yoke. And an axial air gap type brushless motor having a drive circuit member mounted therein, wherein the shaft is rotatably mounted to the shaft, and the tip of the shaft is inserted into a recess of the center of the cover member. 3. The axial pore-type brushless motor incorporating a drive circuit member according to claim 2, wherein the rotor yoke has a reinforcing rib in the shaft support portion. 3. The shaft of claim 2, wherein a tip of the shaft is welded to a center of the rotor yoke, a bearing portion rotatably supporting the shaft is disposed at the center of the stator base, and a base end of the shaft is pivotally supported at the stator base side. An axial air gap brushless motor with a built-in drive circuit member. The rotor according to claim 1, further comprising a rotor provided with a rotor yoke attached to the axial void magnet, the shaft supporting the rotor, and a shaft supporting the rotor, A three-phase concentric armature coil comprising a supporting yoke bracket, a stator base installed in addition to the yoke bracket, and at least three winding concentric armature coils disposed on the stator base, and the winding concentric armature coils, respectively, in plan view A sensorless drive circuit member disposed on the stator base and a cover member covering the stator base, the arm portion of the yoke bracket integrally from the center between the air core armature coil and the drive circuit member. So as to extend radially circumferentially so that a fixing part is formed, and furthermore, yoke bracket An axial air gap brushless with a built-in drive circuit member, wherein a part of the stator base protrudes laterally from the cover member to form a feed terminal part, and an opening of the cover member is provided in the fixing part. motor. 8. The method according to claim 7, wherein the means for installing the cover and the yoke bracket is by laser welding, and the eccentric weight is formed in the shape of a bow in plan view and installed by laser welding on the outside of the axial void magnet. An axial air gap brushless motor with a built-in drive circuit member. 8. The axial air gap brushless motor with a drive circuit member according to claim 7, wherein the rotor yoke is made of a magnetic material having a thickness of 0.15 or less and has a plurality of reinforcing ribs in the shaft support portion. The concentric armature coil according to claim 7, wherein the three-phase concentric armature coils are formed on one side of the stator base so as to overlap with each of the wound concentric armature coils. An axial air gap brushless motor with a drive circuit member, comprising: an air core armature coil formed in one layer on one side of the stator base, and connected in series with the respective winding type air core armature coils. According to claim 7, wherein the base end of the shaft is fixed to the center of the yoke bracket, the eccentric rotor is a bearing is disposed on the shaft support of the rotor yoke, rotatably mounted to the shaft through the bearing, An axial air gap brushless motor incorporating a drive circuit member, characterized in that the tip of the shaft is fitted into a recess in the center of the cover member. 8. The shaft of claim 7, wherein the tip is welded to the shaft support of the rotor yoke, a bearing portion for rotatably supporting the shaft is disposed at the center of the stator base, and the base end of the shaft is pivotally supported on the stator base side. An axial air gap brushless motor with a built-in drive circuit member, characterized in that. An axial pore-type brushless motor having a rotor having a plurality of magnetic poles with an axial pore-type magnet and a stator for driving the rotor through the axial pore, and having a cover for storing them, The rotor is an axial void type brushless motor, characterized in that the inner diameter side of the axial void type magnet is used as an axial support portion. 14. The shaft according to claim 13, wherein a shaft is fixedly attached to the stator, the axial void magnet is formed of a sintered metal, and means for using the inner diameter side as the axial support portion includes an inner diameter of the sintered bearing and the axial void magnet. An axial air gap brushless motor, characterized in that the side is welded. 15. The axial pore-shaped brush according to claim 14, wherein the sintered bearing includes an axially protruding portion from the axial pore-shaped magnet and welds the outside diameter of the protruding portion and the inner diameter side of the magnet. Lease motor. 14. An axial pore-type brushless motor according to claim 13, wherein a bearing is fixedly attached to the stator, and means for using the inner diameter side of the axial void magnet as an axial support is welded to the inner diameter side of the shaft. 14. The axial pore-type brushless motor according to claim 13, wherein a magnet locking means is provided on the shaft, and the magnet is fixedly attached to the shaft through the magnet locking means. The axial air gap brushless motor according to claim 13, wherein a thin yoke plate is further provided on at least the opposite side of the stator of the axial air gap magnet. 19. The axial void brush according to claim 18, wherein the axial void magnet is made of a resin, and a metal member is bonded to an inner diameter of the resin axial void magnet and axially supported by the metal member. Rees motor. The rotor according to any one of claims 13 to 19, a bracket for rotatably supporting the rotor through an axis, a stator base provided in addition to the bracket, and a plurality of air core armatures disposed on the stator base. A drive circuit member is disposed in the stator base so as to be within the thickness of the air core armature coil in a space in which the air core armature coil is not disposed within a coil and an arrangement area that is made to have a substantially outer diameter of the air core armature coil. The bracket has an axial support at its center, an arm portion extending radially following the axial support portion, and a fixed portion integral with the arm portion, and viewed in plan from a space portion surrounded by the arm portion and the fixing portion. Axial air gap brushless, characterized in that a portion of the drive circuit member is accommodated Emitter. 14. A copper tungsten alloy according to claim 13, characterized in that the bow-shaped eccentric weight having a welding margin at least on the opposite side of the stator is integrated by welding in the welding margin at least outside the axial void magnet. Axial void brushless motor. 22. The axial pore-type brushless motor of claim 21, wherein at least a portion of the thin yoke plate hangs on the outer diameter of the magnet, and an eccentric weight is integrated with the hanged portion. 23. The axial pore-type brushless motor according to claim 22, wherein the hanged end has a catch portion bent outwardly and the eccentric weight is coupled to the catch portion. 24. An eccentric rotor according to any one of claims 21 to 23, a bracket for rotatably supporting the eccentric rotor through an axis, a stator base provided in addition to the bracket, and a plurality of stator bases. A drive circuit member is disposed in the stator base so as to be within the thickness of the air core armature coil in a space portion in which the air core armature coil is not disposed in an air core armature coil and an arrangement area where the outer core armature coil has a substantially outer diameter. The bracket is an axial air gap type, characterized in that an axial support portion, an arm portion extending in the radial direction subsequent to the axial support portion, and an integral fixing portion exist between the arm portion with an empty space therebetween. Brushless motor. 25. The stator base according to claim 24, wherein the stator base is made of a flexible substrate, and a portion of the drive circuit member is disposed in the space portion when viewed in plan view, and at least a stator base portion at a position where a portion of the drive circuit member is disposed is formed. An axial air gap brushless motor, wherein the air core armature coil is integrally formed with a resin so as to be accommodated within the thickness of the bracket. 25. The yoke bracket of claim 24, wherein the yoke bracket has a thickness of 0.2 mm or less and a base end of the shaft is fixed at the center thereof, and resin is integrated at least in the space portion, so that the eccentric rotor is made through a bearing disposed on the shaft support of the rotor yoke. An axial pore-type brushless motor, rotatably mounted to the shaft, the tip of the shaft being fitted to a recess in the center of the cover member. 25. The yoke bracket of claim 24, wherein the yoke bracket has a thickness of 0.2 mm or less and a bearing is provided in the central shaft support, at least the resin is integrated in the empty space, and the shaft is welded to the shaft support of the rotor yoke. And a bearing portion rotatably supporting the shaft is disposed at the center of the stator base, and the proximal end of the shaft is pivotally supported on the stator base side. The method of claim 1, wherein the stator base is disposed under the yoke bracket, the drive circuit member is stored in a space portion consisting of the arm portion and the fixing portion, and integrally molded of resin including the air core armature coil. Axial air-gauge brushless motor. The axial air gap brushless motor according to claim 1, wherein a gear is disposed on the rotor, and a window for gear connection is disposed on the cover facing the radial direction of the gear. 30. The axial pore-type brushless motor of claim 29, wherein the gear is integrally formed with the rotor case.