JP4915540B2

JP4915540B2 - DC brushless motor

Info

Publication number: JP4915540B2
Application number: JP2000319412A
Authority: JP
Inventors: 一也中村
Original assignee: Namiki Precision Jewel Co Ltd; Adamant Namiki Precision Jewel Co Ltd
Current assignee: Namiki Precision Jewel Co Ltd; Adamant Namiki Precision Jewel Co Ltd
Priority date: 2000-10-19
Filing date: 2000-10-19
Publication date: 2012-04-11
Anticipated expiration: 2020-10-19
Also published as: JP2002136034A

Description

【０００１】
【発明の属する技術分野】
本発明は、主に医療用機器や精密測定装置などに用いられる小径DCブラシレスモータの改良構造であり、より詳細には、輸液ポンプ又は透析用ポンプ等に用いられる外径φ12mm以下のインナーロータマグネット型のDCブラシレスモータの鉄損・発熱対策に関するものである。
【０００２】
【従来の技術】
従来より、インナーロータマグネット型のDCブラシレスモータは、ハウジングとして金属磁性材料を切削加工、又はプレス加工等により形成した単一鋼塊の略円筒状のパーツ部品を用いるのが一般的であった。
【０００３】
例えば、図２に示すDCブラシレスモータのように、円筒状マグネット4とその中心を貫通するシャフト3からなるインナーロータ部全体を、円筒状ハウジング1の両端開口部に位置するフランジ2の軸中心位置で、軸受6により回転自在に軸支し、これをハウジング1内に固定配置した界磁コイル5への通電・転流により発生する回転磁界により回転駆動させるDCブラシレスモータ110が知られている。
【０００４】
【発明が解決しようとする課題】
しかしながら上記図２のようなインナーロータマグネット型DCブラシレスモータ110では、モータ動作時のロータ回転中に、ロータマグネット4の磁束が、磁性材料からなるハウジング1を横切るため、ハウジング1中にうず電流が流れ、鉄損が発生するという問題が以前から指摘されていた。
【０００５】
つまり従来のインナーロータマグネット型のモータ構成の場合、ハウジングが一体の単一鋼塊であり、電気抵抗が小さく、うず電流が流れやすいため、結果的にうず電流損の増大や、発熱の促進を大きく招いていた。
【０００６】
この改善のため、非磁性材料からなる外装ハウジング内部に、薄板状の積層鋼板（コア）を軸方向に多重に収めた二層ハウジング構造とすることにより、うず電流を流れにくくする手段が提案されている。しかし積層鋼板（コア）をハウジング内に内包する場合、ハウジングとなる外装ケースの厚み分、モータ外径寸法が増大してしまい、小径化が難しく、また各部品の小型化にともなう組み立てのしにくさから、工数が増大し、特に外径φ12mm以下の小径モータには適用が困難であった。
【０００７】
本発明は上記課題を解決するもので、外径φ12mm以下の小径のインナーロータマグネット型モータであっても、組み立てにくさによる工数の増大を解消するとともに、うず電流損を低減し、高効率で発熱の少ないモータを提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記の目的を達成するために、外径φ12mm以下のインナロータマグネット型のDCブラシレスモータにおいて、複数枚の略リング状磁性鋼板を互いに電気的に絶縁された状態で積層した積層コアを、界磁コイルの外周部円筒軸方向であって、少なくともインナーロータマグネット全長の領域幅に配置し、前記積層コアの内径の一部に、少なくとも一箇所以上の樹脂導入溝が形成されており、さらに前記界磁コイル及び通電のための給電機構部品、及び前記積層コアを、ステータ円筒軸方向両端に位置する該モータのフランジ嵌合部を形成しつつ樹脂により一体成形し、前記樹脂導入溝は、前記樹脂によって充填されており、かつ前記積層コアを内包する外装ケースを備えておらず、前記積層コア外周面が露出したステータ構造のDCブラシレスモータとするものである。
【０００９】
この発明によれば、例えば外径φ12mm、またはそれ以下の小径のインナーロータマグネット型DCブラシレスモータであっても、従来のハウジング相当部、つまり本発明における積層コアの電気抵抗が増加するため、うず電流が流れにくくなり、これによりうず電流損を大幅に低減することができ、かつ、この発明によれば、従来の形態に対し、モータ全体の外径寸法を増加させることなく総磁路断面積（積層コア総断面積）を同一に維持することができる。よってモータ特性を低下させることはない。
【００１０】
さらに、この発明によれば、積層コアの外周表面が露出する構造であるため、外部外気と接する接触面積が大きくなり、効率的な放熱が行える。
【００１１】
さらに、積層コアに設けた溝は射出成形機からの樹脂の導入をスムーズにする役目と、樹脂が充填されることにより積層コアの軸回転方向のずれ止めの役割を果たすものである。
【００１２】
またその他の形態としては、前記積層コア内外径の凹溝形状以外として、例えば略リング状積層コア板面上に一箇所以上の貫通穴部を設けても前記溝と同様な効果が得られる。
【００１３】
また請求項４及び５にかかるDCブラシレスモータにあっては、前記一体成形する樹脂材料として、バルクモールディングコンパウンド（BMC）、エポキシ、あるいはその充填材含有物の熱硬化性樹脂、66ナイロン、PBT、PPS、あるいはそれらの充填材含有物の熱可塑性樹脂を用い、耐熱性、寸法精度を考慮して適宣選定する。また前記充填材は例えば、酸化アルミニウム、窒化アルミニウム等の熱良伝導性素材であることが望ましい。
【００１４】
これらにより、従来例で示した非磁性材料の外装ハウジングケースが不要となり、外径寸法の増大を解消できるとともに、界磁コイル、給電機構部品、略リング状積層コアがコンパクトに一体部品構造とできるため、組み立ての簡易化による工数低減を実現できる。
【００１５】
また、これにより、うず電流損を低減して、高効率で発熱の少ないDCブラシレスモータが実現できる。さらに、積層コア外周面が露出しているため、放熱が効率的に行われ、発熱を抑制することができる。
【００１６】
【発明の実施の形態】
以下、本発明にかかるDCブラシレスモータの好適な実施の形態について、図を参照し、詳細に説明する。なお、本発明はこの実施の形態に限定されるものではなく、下記形態の構造は説明のための一例とする。
【００１７】
図１は、本発明の実施の形態にかかるDCブラシレスモータの構成を示す側断面図である。この構造は、インナーロータマグネット型のDCブラシレスモータ100として、円筒状マグネット4とその中心を貫通するシャフト3からなるインナーロータ部を、略リング状積層コア11の両端フランジ嵌合部9に位置するフランジ2の軸中心位置で軸受6により回転自在に軸支し、これを積層コア11内径側に固定配置した界磁コイル5への通電・転流により発生する回転磁界により回転駆動させる外径φ12mmのモータである。
【００１８】
積層コア11は、前記図２の従来構造のように、磁性材料を切削、又はプレス加工等により形成した単一鋼塊の略円筒状のパーツ部品を用いるものではなく、図１の丸枠内で示す略リング状薄葉鋼板11Aの複数枚重ね合わせにより形成されており、同積層コア11と界磁コイル5、給電機構部品7とを、樹脂でインサートモールドにより一体化し、ステータを構成している。
【００１９】
図１のように、外径φ12mm以下のインナロータマグネット型DCブラシレスモータでは、磁性材料からなる前記薄葉鋼板（積層鋼板）11A、11B、11C、…からなる積層コア11を狭支するように、積層コア11、界磁コイル5、給電機構部品7、及び補強板7'を樹脂で一体にモールド成形し、その際、同時にフランジ嵌合部9を形成している。また積層コア11の外周面は外部に露出しており、界磁コイル5への通電により発生した熱、あるいは鉄損に起因した熱等を積層コア11を介して直接外気へ放熱ができる構造となっている。
【００２０】
一般的に、うず電流損低減に対する積層鋼板適用の効果は既に知られているが、図１のような外径φ12mm、またはそれ以下の小径のインナーロータマグネット型DCブラシレスモータにおいては、その適用が寸法的な制限のため難しく実用化できなかったが、これに対し図１に示す樹脂モールド一体化構造のものは、外装ケースが不要になり、寸法上も小径化が可能となる。
【００２１】
前記図１の丸枠内に示す略リング状薄葉鋼板（積層鋼板）11A、11B、11C、…は、例えばケイ素鋼板が用いられ、薄葉状の鋼板間は絶縁されており、全体の積層コアとして電気抵抗が大きくなるため、うず電流が流れにくくなり、有効トルクの拡大と発熱の抑制ができ、よって総合的にモータ性能を考えた場合、同一外径寸法でもモータの高性能化を図ることができる。また、構造は積層コア外周面が露出しており、コイル通電により生成した熱、あるいは鉄損に起因した熱等は効率よく放熱される。
【００２２】
下記表１に本発明の実施例（例えば図１の構造）と従来例（例えば図２の構造）との損失比率ηLOSS とモータ外装表面の発熱飽和温度Ｔの比較値を示す。両者はステータ構造が異なる以外、外形寸法・マグネット材質及び寸法・軸受・界磁コイルなどを含め同一仕様である。またモータ駆動電圧は共にDC 5 Vとし、無負荷運転テストを行った。また、環境温度は25℃一定とした。
【００２３】
このとき損失比率ηLOSS (％)は、無負荷電流Ｉo (mA)および起動電流Ｉs (mA)を実測し、損失比率ηLOSS (％)＝［無負荷電流Ｉo (mA)／起動電流Ｉs (mA)］×100の計算式により算出した。
【００２４】
【表１】

【００２５】
前記表１の平均値を比較すると、従来例の損失比率40.3％、ハウジング飽和温度44℃であるのに対し、本発明の実施例の損失比率は6.8％、ステータ部（積層コア部分）飽和温度29℃であり、明らかに本発明の効果が定量的に確認できた。
【００２６】
なお、この実施の形態では、外径φ12mmのインナーロータマグネット型DCブラシレスモータを例にとって説明したが、詳細はこれに限定されるものではない。
【００２７】
【発明の効果】
以上説明したように、本発明によれば、例えば外径φ12mm、またはそれ以下の小径のインナーロータマグネット型DCブラシレスモータであっても、モータ外径を増加させることなく、うず電流損とそれに起因した発熱を大幅に低減することができる。
【００２８】
つまり、積層コアでステータヨーク部を構成したので、ヨーク部全体が互いに絶縁された薄葉鋼板により電気的に分割され、電気抵抗が増大し、ヨーク内に発生するうず電流が小さくなるため、うず電流損が低減される。
【００２９】
また、本発明によれば、前記界磁コイル及び通電のための給電機構部品（例えばFPCと補強板）と、前記界磁コイル外周部円筒軸方向に位置する略リング状積層コアとを、樹脂により一体成形し、かつ同略リング状積層コアの外周表面を外部に露出する構造としたので、界磁コイル通電により発生した熱、あるいはヨーク部分での鉄損に起因した熱などを、効率よくモータ外部に放熱することができ、モータの発熱飽和温度を抑制することができる。よって、発熱抑制によるモータの高性能化を図ることができる。
【００３０】
さらに、本発明のステータ部樹脂一体構造により、組み立て部品点数を削減することができるため、モータの組立工数、組立時間を低減することができる。
【００３１】
また、本発明によれば、略リング状積層コアの少なくとも一箇所以上に、樹脂導入溝が形成されているので、製造工程時に射出成形機からの樹脂の導入をスムーズにできるとともに、樹脂が溝に充填されることにより積層コアの軸回転方向のずれを防止でき、また、樹脂部と積層コアとの結合強度を向上させることができるため、ステータとしての必要強度を確保することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係るDCブラシレスモータの構成を示す側断面図。
【図２】従来のDCブラシレスモータの構成を示す側断面図。
【符号の説明】
1 ハウジング
2 フランジ
3 シャフト
4 マグネット
5 界磁コイル
6 軸受
7 給電機構部品
7' 補強板
9 フランジ嵌合部
11 積層コア
11A、11B、11C、… 薄葉鋼板（積層鋼板）
12 樹脂導入部
100 DCブラシレスモータ
110 DCブラシレスモータ[0001]
BACKGROUND OF THE INVENTION
The present invention is an improved structure of a small-diameter DC brushless motor mainly used for medical equipment and precision measuring devices, and more specifically, an inner rotor magnet having an outer diameter of φ12 mm or less used for an infusion pump or a dialysis pump. This relates to measures against iron loss and heat generation of DC brushless motors.
[0002]
[Prior art]
Conventionally, an inner rotor magnet type DC brushless motor has generally used a substantially cylindrical part part of a single steel ingot formed by cutting or pressing a metal magnetic material as a housing.
[0003]
For example, as in the DC brushless motor shown in FIG. 2, the entire inner rotor portion consisting of the cylindrical magnet 4 and the shaft 3 passing through the center thereof is placed at the axial center position of the flange 2 positioned at both ends of the cylindrical housing 1. Thus, there is known a DC brushless motor 110 that is rotatably supported by a bearing 6 and is rotationally driven by a rotating magnetic field generated by energization / commutation of the field coil 5 fixedly disposed in the housing 1.
[0004]
[Problems to be solved by the invention]
However, in the inner rotor magnet type DC brushless motor 110 as shown in FIG. 2 above, since the magnetic flux of the rotor magnet 4 traverses the housing 1 made of a magnetic material while the rotor is rotating during motor operation, an eddy current is generated in the housing 1. The problem of flow and iron loss has been pointed out for some time.
[0005]
In other words, in the case of the conventional inner rotor magnet type motor configuration, the housing is an integral single steel ingot, with low electrical resistance and easy eddy current flow, resulting in increased eddy current loss and accelerated heat generation. Invited greatly.
[0006]
For this improvement, a means to make it difficult to flow eddy current by adopting a two-layer housing structure in which thin laminated steel plates (cores) are accommodated in the axial direction inside the exterior housing made of nonmagnetic material has been proposed. ing. However, when a laminated steel plate (core) is encased in a housing, the outer diameter of the motor increases by the thickness of the outer case that becomes the housing, making it difficult to reduce the diameter, and for assembling as each component is reduced in size. Therefore, the number of man-hours has increased, and it has been difficult to apply to small-diameter motors having an outer diameter of 12 mm or less.
[0007]
The present invention solves the above-mentioned problems.Even if it is an inner rotor magnet type motor with a small outer diameter of φ12 mm or less, it eliminates an increase in man-hours due to difficulty in assembly, reduces eddy current loss, and achieves high efficiency. The object is to provide a motor that generates little heat.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, in an inner rotor magnet type DC brushless motor having an outer diameter of φ12 mm or less, a laminated core obtained by laminating a plurality of substantially ring-shaped magnetic steel plates in a state of being electrically insulated from each other, The outer peripheral portion of the coil is in the axial direction of the cylinder and is disposed at least in the region width of the entire length of the inner rotor magnet , and at least one resin introduction groove is formed in a part of the inner diameter of the laminated core. A magnetic coil, a power feeding mechanism component for energization, and the laminated core are integrally formed of resin while forming flange fitting portions of the motor positioned at both ends of the stator cylindrical axis, and the resin introduction groove is formed of the resin DC brushless motor having a stator structure in which the outer peripheral surface of the laminated core is exposed without including an outer case enclosing the laminated core It is what.
[0009]
According to the present invention, for example, even in an inner rotor magnet type DC brushless motor having a small outer diameter of φ12 mm or less, the electrical resistance of the conventional housing equivalent part, that is, the laminated core in the present invention is increased. This makes it difficult for current to flow, thereby significantly reducing the eddy current loss. According to the present invention, the total magnetic path cross-sectional area can be increased without increasing the overall outer diameter of the motor, compared to the conventional configuration. The (laminated core total cross-sectional area) can be kept the same. Therefore, the motor characteristics are not deteriorated.
[0010]
Furthermore, according to the present invention, since the outer peripheral surface of the laminated core is exposed, the contact area in contact with the outside air is increased and efficient heat dissipation can be performed.
[0011]
Further, the groove provided in the laminated core plays a role of smooth introduction of the resin from the injection molding machine, and plays a role of preventing the deviation in the axial rotation direction of the laminated core by being filled with the resin.
[0012]
As another form, the same effect as that of the groove can be obtained even if, for example, one or more through-hole portions are provided on the substantially ring-shaped laminated core plate surface other than the groove shape of the inner and outer diameters of the laminated core.
[0013]
Further, in the DC brushless motor according to

claims

4 and 5, as the resin material to be integrally molded, bulk molding compound (BMC), epoxy, or a thermosetting resin containing the filler, 66 nylon, PBT, Use PPS or a thermoplastic resin containing those fillers, and select an appropriate material considering heat resistance and dimensional accuracy. The filler is preferably a heat-conductive material such as aluminum oxide or aluminum nitride.
[0014]
As a result, the outer housing case of the nonmagnetic material shown in the conventional example becomes unnecessary, and the increase in the outer diameter can be eliminated, and the field coil, the power feeding mechanism component, and the substantially ring-shaped laminated core can be made into a compact and integrated component structure. Therefore, man-hours can be reduced by simplifying assembly.
[0015]
This also reduces the eddy current loss and realizes a DC brushless motor with high efficiency and low heat generation. Furthermore, since the outer peripheral surface of the laminated core is exposed, heat can be efficiently dissipated and heat generation can be suppressed.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a DC brushless motor according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to this embodiment, The structure of the following form is made into an example for description.
[0017]
FIG. 1 is a side sectional view showing a configuration of a DC brushless motor according to an embodiment of the present invention. In this structure, as an inner rotor magnet type DC brushless motor 100, an inner rotor portion composed of a cylindrical magnet 4 and a shaft 3 penetrating the center thereof is positioned at both end flange fitting portions 9 of the ring-shaped laminated core 11. An outer diameter φ12 mm that is rotatably supported by a rotating magnetic field generated by energizing / commutating the field coil 5 that is rotatably supported by the bearing 6 at the axial center position of the flange 2 and fixedly arranged on the inner diameter side of the laminated core 11 Motor.
[0018]
The laminated core 11 does not use a substantially cylindrical part part of a single steel ingot formed by cutting or pressing a magnetic material as in the conventional structure of FIG. Is formed by superimposing a plurality of substantially ring-shaped thin leaf steel plates 11A, and the laminated core 11, the field coil 5, and the power feeding mechanism component 7 are integrated with resin by insert molding to constitute a stator. .
[0019]
As shown in FIG. 1, in an inner rotor magnet type DC brushless motor having an outer diameter of φ12 mm or less, the laminated core 11 composed of the thin steel plates (laminated steel plates) 11A, 11B, 11C,. The laminated core 11, the field coil 5, the power feeding mechanism component 7, and the reinforcing plate 7 ′ are integrally molded with resin, and at the same time, the flange fitting portion 9 is formed at the same time. In addition, the outer peripheral surface of the laminated core 11 is exposed to the outside, and heat generated by energizing the field coil 5 or heat caused by iron loss can be radiated directly to the outside air via the laminated core 11. It has become.
[0020]
In general, the effect of using laminated steel sheets for reducing eddy current loss is already known. However, in the case of an inner rotor magnet type DC brushless motor having a small outer diameter of φ12 mm as shown in FIG. However, the resin mold integrated structure shown in FIG. 1 eliminates the need for an exterior case, and the size can be reduced in size.
[0021]
The substantially ring-shaped thin steel plates (laminated steel plates) 11A, 11B, 11C,... Shown in the round frame in FIG. 1 are made of, for example, silicon steel plates, and the thin leaf steel plates are insulated from each other. Since electric resistance increases, eddy current does not flow easily, and effective torque can be increased and heat generation can be suppressed. Therefore, when considering overall motor performance, motor performance can be improved even with the same outer diameter. it can. In addition, the outer peripheral surface of the laminated core is exposed in the structure, and heat generated by energizing the coil, heat due to iron loss, or the like is efficiently radiated.
[0022]
Table 1 below shows a comparative value of the loss ratio ηLOSS and the heat generation saturation temperature T of the motor exterior surface between the example of the present invention (for example, the structure of FIG. 1) and the conventional example (for example, the structure of FIG. 2). Both have the same specifications, including the external dimensions, magnet material and dimensions, bearings, field coils, etc., except that the stator structure is different. The motor drive voltage was DC 5 V, and a no-load operation test was conducted. The ambient temperature was constant at 25 ° C.
[0023]
At this time, the loss ratio ηLOSS (%) is obtained by actually measuring the no-load current Io (mA) and the starting current Is (mA), and the loss ratio ηLOSS (%) = [no-load current Io (mA) / starting current Is (mA). ] Calculated by a formula of x100.
[0024]
[Table 1]

[0025]
Comparing the average values in Table 1 above, the loss ratio of the conventional example is 40.3% and the housing saturation temperature is 44 ° C., whereas the loss ratio of the embodiment of the present invention is 6.8% and the stator part (laminated core part) saturation temperature. It was 29 ° C., and clearly the effect of the present invention could be confirmed quantitatively.
[0026]
In this embodiment, the inner rotor magnet type DC brushless motor having an outer diameter of φ12 mm has been described as an example, but the details are not limited thereto.
[0027]
【Effect of the invention】
As described above, according to the present invention, for example, even an inner rotor magnet type DC brushless motor having a small outer diameter of φ12 mm or less, an eddy current loss and its cause can be obtained without increasing the motor outer diameter. The generated heat can be greatly reduced.
[0028]
In other words, since the stator yoke portion is composed of the laminated core, the entire yoke portion is electrically divided by the thin steel plates insulated from each other, increasing the electrical resistance and reducing the eddy current generated in the yoke. Loss is reduced.
[0029]
Further, according to the present invention, the field coil and a power feeding mechanism component for energization (for example, FPC and a reinforcing plate) and the substantially ring-shaped laminated core positioned in the cylindrical direction of the outer periphery of the field coil are made of resin. Since the outer peripheral surface of the substantially ring-shaped laminated core is exposed to the outside, the heat generated by energizing the field coil or the heat caused by the iron loss at the yoke portion can be efficiently Heat can be radiated to the outside of the motor, and the heat generation saturation temperature of the motor can be suppressed. Therefore, it is possible to improve the performance of the motor by suppressing heat generation.
[0030]
Furthermore, since the number of assembly parts can be reduced by the stator part resin integrated structure of the present invention, the number of assembly steps and the assembly time of the motor can be reduced.
[0031]
Further, according to the present invention, since the resin introduction groove is formed in at least one place of the substantially ring-shaped laminated core, the resin can be smoothly introduced from the injection molding machine during the manufacturing process, and the resin is grooved. By being filled, the displacement of the laminated core in the axial rotation direction can be prevented, and the bonding strength between the resin portion and the laminated core can be improved, so that the necessary strength as a stator can be ensured.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a configuration of a DC brushless motor according to an embodiment of the present invention.
FIG. 2 is a side sectional view showing a configuration of a conventional DC brushless motor.
[Explanation of symbols]
1 Housing
2 Flange
3 shaft
4 Magnet
5 Field coil
6 Bearing
7 Power supply mechanism parts
7 'reinforcement plate
9 Flange fitting
11 laminated core
11A, 11B, 11C, ... Thin-leaf steel sheet (laminated steel sheet)
12 Resin introduction part
100 DC brushless motor
110 DC brushless motor

Claims

In inner rotor magnet type DC brushless motor with outer diameter φ12mm or less,
A laminated core in which a plurality of substantially ring-shaped magnetic steel plates are laminated in a state of being electrically insulated from each other,
In the outer peripheral cylindrical axis direction of the field coil, disposed at least in the region width of the entire length of the inner rotor magnet,
At least one resin introduction groove is formed in a part of the inner diameter of the laminated core ,
Further, the field coil and the feeding mechanism component for energization, and the laminated core are integrally formed with resin while forming flange fitting portions of the motor located at both ends of the stator cylindrical axis direction,
The resin introduction groove is filled with the resin,
A DC brushless motor characterized by having a stator structure that does not include an outer case that encloses the laminated core and that has an outer peripheral surface of the laminated core exposed.

In inner rotor magnet type DC brushless motor with outer diameter φ12mm or less,
A laminated core in which a plurality of substantially ring-shaped magnetic steel plates are laminated in a state of being electrically insulated from each other,
In the outer peripheral cylindrical axis direction of the field coil, disposed at least in the region width of the entire length of the inner rotor magnet,
At least one resin introduction groove is formed in a part of the outer diameter of the laminated core ,
Further, the field coil and the feeding mechanism component for energization, and the laminated core are integrally formed with resin while forming flange fitting portions of the motor located at both ends of the stator cylindrical axis direction,
The resin introduction groove is filled with the resin,
A DC brushless motor characterized by having a stator structure that does not include an outer case that encloses the laminated core and that has an outer peripheral surface of the laminated core exposed.

In inner rotor magnet type DC brushless motor with outer diameter φ12mm or less,
A laminated core in which a plurality of substantially ring-shaped magnetic steel plates are laminated in a state of being electrically insulated from each other,
In the outer peripheral cylindrical axis direction of the field coil, disposed at least in the region width of the entire length of the inner rotor magnet,
At least one or more through holes are formed on the plate surface of the laminated core ,
Further, the field coil and the feeding mechanism component for energization, and the laminated core are integrally formed with resin while forming flange fitting portions of the motor located at both ends of the stator cylindrical axis direction,
The through hole is filled with the resin,
A DC brushless motor characterized by having a stator structure that does not include an outer case that encloses the laminated core and that has an outer peripheral surface of the laminated core exposed.

The resin material to be integrally molded is bulk molding compound (BMC), epoxy, thermosetting resin containing filler, 66 nylon, PBT, PPS, or thermoplastic resin containing filler. The DC brushless motor according to any one of claims 1 to 3.

The DC brushless motor according to claim 4, wherein the filler is a heat conductive material such as aluminum oxide or aluminum nitride.

The DC brushless motor according to any one of claims 1 to 5, wherein the power supply mechanism component is an FPC.