JP2004208446A

JP2004208446A - Electric motor, refrigeration / air-conditioning device, electric motor manufacturing method, electric motor mold device

Info

Publication number: JP2004208446A
Application number: JP2002376363A
Authority: JP
Inventors: Noriaki Matsunaga; 訓明松永; Takayuki Hanaki; 隆行花木; Katsumi Shibayama; 勝巳柴山; Tomoaki Oikawa; 智明及川; Yasuyoshi Tajima; 庸賀田島; Sadami Okugawa; 貞美奥川; Kazuya Omura; 和也尾村; Toshio Arai; 利夫荒井
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-12-26
Filing date: 2002-12-26
Publication date: 2004-07-22
Anticipated expiration: 2022-12-26
Also published as: JP3801132B2

Abstract

【課題】電動機のインシュレ−タはその製造時にバリ処理が必要、金型腐食性のガスを生成する、成形サイクルが長い、成形収縮が大きいため薄肉化が難しいなどの課題があった。
【解決手段】鉄心とコイル間の絶縁であるインシュレータを、ＤＳＣにより測定される融点が３５０℃以下、結晶化潜熱が１０Ｊ／ｇ以下、溶融時の生成ガス量が２００ｐｐｍ以下、繊維状無機強化材、もしくは無機充填材のうちから選ばれる少なくとも１つを９５重量％以下含有し、ステアリン酸系または脂肪酸アミド系の滑剤を添加しないか、３．０重量％以下添加した液晶ポリエステル樹脂成形品とし、ゲートサイズを１．２ｍｍ□以下、巻枠部の表面粗さを１０μｍＲｚ以下とする。更に結晶化潜熱の低いＬＣＰ樹脂を使用し、薄肉に成形する。
【選択図】図１An insulator for an electric motor has a problem that a burr treatment is required at the time of manufacturing, a mold corrosive gas is generated, a molding cycle is long, and a molding shrinkage is large, so that it is difficult to reduce the wall thickness.
An insulator, which is an insulation between an iron core and a coil, has a melting point measured by DSC of 350 ° C. or less, a crystallization latent heat of 10 J / g or less, a generated gas amount at the time of melting of 200 ppm or less, and a fibrous inorganic reinforcing material. Or a liquid crystal polyester resin molded article containing at least one selected from inorganic fillers in an amount of 95% by weight or less and no stearic acid-based or fatty acid amide-based lubricant added or 3.0% by weight or less, The gate size is 1.2 mm □ or less, and the surface roughness of the winding frame is 10 μmRz or less. Further, the LCP resin having a low crystallization latent heat is used to form a thin wall.
[Selection diagram] Fig. 1

Description

【０００１】
【発明の属する技術分野】
本発明は、電動機の技術に関するもので、例えば冷媒圧縮機及びこの冷媒圧縮機を用いた冷凍空調機に係わり、この冷媒圧縮機に搭載される電動機に関する。
【０００２】
【従来の技術】
近年冷蔵庫やエアコンの圧縮機用電動機などには、高効率化とコンパクト化の目的で、複数のティースにまたがらずに１つのティースの回りに集中的に巻線を巻く集中巻式固定子を採用した電動機が検討され、ティ−スと巻線間には絶縁材として樹脂成形品が用いられるのが一般的である。
【０００３】
圧縮機内部には、冷媒を圧縮する圧縮要素部とこの圧縮要素を駆動させる電動機が内蔵され、−２０℃以下から１２０℃を越える環境において、冷媒と冷凍機油が貯留され、この混合液に晒されながら使用される。冷凍機油は圧縮要素部のシ−ル、潤滑を行うと共に冷媒ガスと混合して冷凍回路内を循環しながら、毛細管などの絞り部を通過して蒸発器、圧縮機に戻る。このため絶縁材などの樹脂が冷凍機油に溶出すると、圧縮要素部のシ−ル性・潤滑性の低下、絞り部の閉塞などの問題を発生しうる可能性がある。
【０００４】
そこで圧縮機内部の電動機の絶縁部材として、熱的安定性、耐加水分解性等の化学的安定性が高く、冷媒および冷凍機油に対する耐久性に優れるポリフェニレンサルファイド（以下ＰＰＳ樹脂）等を使用する検討が進められてきた。
【０００５】
従来の冷媒圧縮機の集中巻電動機の固定子および回転子の構造は、特許文献１に示す様に、固定子、この固定子ヨーク部の内周または外周方向に突出したティース部、ティ−スに直接巻装される巻線、巻線とティースとの絶縁を行う絶縁部材であるインシュレ−タ、回転子に埋設された永久磁石にて構成されている。
【０００６】
この集中巻電動機に使用されるインシュレ−タは、上下２分割され円環状固定子に挿入され、複数のティ−ス毎に分割されていないいわゆる一体タイプのインシュレ−タである。このインシュレ−タは、コイルが直接巻装される巻枠部と、巻枠長手延長方向において固定子の内径または外径側に配置される壁部と、その壁部には電線の結線を行うための端子箱とを備え、樹脂注入口であるゲ−トは壁部の先端に設けられている。
【０００７】
この絶縁部材は特許文献１に示す様に樹脂モールド成形品もしくはティース部と一体モールド化されたもので曲げ弾性率、曲げ強度や寸法を規定し、且つ、オリゴマの抽出量の少ないＰＰＳ、ＰＡ、ＰＢＴ、ＬＣＰなどが検討されている。
なおこの中の液晶ポリエステルであるＬＣＰの組成物の特性に関しては特許文献２にて説明されている。
【０００８】
【特許文献１】
特開２００１−５５９７９号公報（請求項１−３および請求項５、表１、図１、図２）
【特許文献２】
特開平１０−４６００９号公報（００１４欄乃至００１８欄）
【０００９】
【発明が解決しようとする課題】
しかしながら、使用を検討されているＰＰＳ樹脂を用いてもオリゴマ−含有量の多いものは冷凍回路内で、オリゴマ−成分を溶出し、低温部に析出して回路を閉塞させる不具合があった。またＰＰＳ樹脂等は成分中に硫黄を含むため、溶融時に重合未反応成分等から硫黄を含んだ腐食性のガスを発生するため、金型寿命が短くなるなどの問題があった。
【００１０】
成形品に使用される樹脂は一般に高結晶性の樹脂であり、成形時の金型温度を高くし、金型内で保持する時間を長くして結晶化を促進させる必要があり、成形サイクルが長いとういう課題があった。またこれらの樹脂はバリが生成しやすいため、剥離したバリによる冷凍回路閉塞を防止するために、成形品のバリ処理が不可欠であった。ショットブラスト等のバリ処理を行う場合にはストレスにより成形品にクラックの生ずる恐れがあり、絶縁機能として必要とされる以上の肉厚としなければ成らず、加工費、材料費が高くなるという課題があった。ＬＣＰなどの樹脂を使用しようとしても複雑な成形品を製造する量産に対し多くの問題があるとともに、材料費も高いという問題があった。
【００１１】
また、固定子ティ−スと巻線間の絶縁材として成形した樹脂をティースに挿入する方式において、部位により収縮量絶対値の差違が大きい樹脂では、鉄心と樹脂成形品との挿入クリアランスが不均一となり、収縮率の少ない部分のクリアランスは大きくなるため、巻線工程における巻線張力や振動による巻乱れから、巻き込まれる量が減少して、スロット面積に対する巻線断面の比率である占線率が低下し、すなわち電動機の効率が低下を引き起こす。逆に収縮率の大きい部位はクリアランスが小さいかマイナス公差となり、ティースへの挿入時や巻線工程での巻線張力によりに成形品にクラックを生じ、絶縁機能を満足させられない。そのため電動機の効率と絶縁耐力を両立するためには、樹脂成形品の収縮率を小さく留めるように成形時の冷却時間を長くするか、絶縁機能として必要とされる以上の肉厚としなければならないという課題があった。
【００１２】
従来の集中巻式電動機に使用される絶縁材は、直接巻線が巻装される巻枠部と、巻枠長手延長方向において固定子の内径または外径側に設けた壁部と、内径または外径壁部に巻線の結線を行うための端子箱部より構成された樹脂成形品が用いられるが、樹脂注入口であるゲ−トを壁部頂部に設けた場合、多くのプレ−ト構成の金型での成形とする必要があり、金型構成部品点数が多く金型費用が嵩み製造時間がかかるという問題があった。以上の様に電動機の構造に対し、信頼性の高い絶縁物成形品を適用する場合安価で大量生産可能な製造が困難であるという問題があった。
【００１３】
本発明は以上のような問題を解決するもので、高効率、且つ、信頼性が高く大量生産が可能な電動機を提案するものである。更に製造サイクルが短く生産性の良い電動機の製造方法を提案するものである。更に簡単な構成で寿命の長いこの電動機の金型装置を提案するものである。更に信頼性が高く性能の良い冷凍・空調装置を提案するものである。
【００１４】
【課題を解決するための手段】
本発明の電動機は、固定子を形成するヨークの内周または外周方向に突出した複数ティース部を有する鋼板を積層された鉄心と、ティ−ス部に直接巻装され通電されるコイルと、コイルとティース部間に設けられ絶縁を行う絶縁部材と、積層された鉄心を展開可能にするとともにこの鉄心を一円状に折り曲げて接続可能な鉄心に設けられた連結部と、絶縁部材を形成する成形品であって、融点が３５０゜Ｃ以下、融解時の生成ガス量が２００ｐｐｍ以下で、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を成形して鉄心とコイルを絶縁する樹脂成形品と、を備えたものである。
【００１５】
本発明の電動機は、固定子を形成するヨークの内周または外周方向に突出した複数ティース部を有する鉄心と、ティ−ス部に直接巻装され通電されるコイルと、コイルとティース部間に設けられ絶縁を行う絶縁部材と、絶縁部材を形成する繊維状無機強化材もしくは無機充填材を１０乃至５０重量％含有する液晶ポリエステル樹脂を成形してティース部とコイルを絶縁する樹脂成形品と、を備え、ティース部のコイルが軸方向に巻装される面の絶縁部材の厚みを０．３乃至１．５ｍｍとしたものである。
【００１６】
本発明の電動機の製造方法は、固定子を形成する鉄心に直接巻装され通電されるコイルと鉄心間に設けられ絶縁を行う絶縁部材を、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を金型に注入して樹脂成形品を成形して製造する際、液晶ポリエステル樹脂は融点が３５０゜Ｃ以下、融解時の生成ガス量が２００ｐｐｍ以下であって、結晶化潜熱が１０Ｊ／ｇ以下のものを使用して熱可塑性射出成形する。
【００１７】
本発明の電動機の製造方法は、固定子を形成するヨークの内周または外周方向に突出した複数ティース部を有する鉄心と、ティ−ス部に直接巻装され通電されるコイルと、コイルとティース部間に設けられ絶縁を行う絶縁部材と、を備えた電動機において、絶縁部材を形成するように、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を金型に注入して樹脂成形品を成形する際、金型に前記固定子のティース部を挿入してから、液晶ポリエステル樹脂を注入し、固定子と樹脂成形品を一体に成形するものである。
【００１８】
本発明の電動機の金型装置は、電動機の固定子を形成する鉄心ティース部に直接巻装され通電されるコイルと前記鉄心間に設けられ絶縁を行う絶縁部材を形成するように、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を注入して樹脂成形品を成形する金型であって、前記固定子のティース部を前記金型に挿入してから、前記液晶ポリエステル樹脂を注入して前記固定子と前記樹脂成形品を一体に成形する、前記ティース部の周囲を覆うものである。
【００１９】
【発明の実施の形態】
実施の形態１．
以下、本発明に係わる実施の形態を図１及び図２に基づいて説明する。図１はこの発明の実施の形態１における集中巻型電動機の断面図である。また、図２は図１のスロット部２０を拡大した図である。固定子１は固定子バックヨーク２の内側に突出したティース３に巻線４がインシュレータ５を介して巻かれている。
固定子コア１２は一円状に形成され、巻線４は回転子６が無い状態で固定子コア１２の内径側から巻線機のノズルが挿入されて、このノズルを動かすことによりインシュレータ５を介してティース３に直巻きされる。いわゆる集中巻で巻装される。固定子１に対向して固定子１の内側には磁石７が鉄心の中に埋め込まれた回転子６が回転可能に配置され図示していない軸受で支持される。なお図１の巻線４の説明を分かりやすくするため実物より大きくし、且つ一部しか記載していないが、本発明ではティース３間の溝に密に巻線を巻くことが出来る。なお図１では巻線４の中心部の記載を省略してあるが実際は密着して巻回してある。これにより溝の中央部にティース巻線絶縁用のスペースやし切り（図示せず）を除く範囲を巻線で埋められるので巻線のスペースファクターが良くなり効率の良い電動機が出来る。
【００２０】
インシュレータ５は、エナメル線や絶縁被覆された巻線４と固定子１２のヨーク部２やティース部３との間の絶縁を行なうために設けられるものである。圧縮機に用いるインシュレータ５としては、液晶ポリエステル樹脂（ＬＣＰ樹脂）を用いる。このＬＣＰ樹脂とは、パラヒドロキシ安息香酸(4-HBA)、ヒドロキシナフトエ酸(2,6-HNA)を重合反応させて得られる熱可塑性樹脂である。このＬＣＰ樹脂は従来のインシュレータ材料に比べ、耐熱性や抽出性に優れ、成形時の溶融粘度が低く薄肉での流動特性に優れ、溶融状態から固化するまでの熱量移動量が少ないため、固化速度が非常に速くバリが生成しにくい、という特性とともに２００℃以上の耐熱性（熱変形温度）を有している。
【００２１】
そのため、この電動機を圧縮機の駆動用に使用して高温高圧状態で冷媒や冷凍機油に露出して長期間使用されたとしても信頼性を確保できる。冷媒として、ジフルオロメタン、１，１，１，２，２−ペンタフルオロエタン、１，１，１，２−テトラフルオロエタン、１，１，１−トリフルオロエタン、クロロジフルオロメタン、二酸化炭素、アンモニア、ジメチルエ−テル、プロパン、ブタン、冷凍機油として、エステル系、エ−テル系、グリコ−ル系、アルキルベンゼン系、ポリαオレフィン系、ポリビニールエーテル系、ナフテン系鉱油、パラフィン系鉱油のいずれの組み合わせに対しても安定性が高く、圧縮機電動機のインシュレータとして適している。また、本実施の形態に記載したインシュレータ材料は、薄肉成形する必要があり、この材料は溶融流動性に優れることから有効である。
【００２２】
本発明に使用する液晶ポリエステル樹脂（ＬＣＰ樹脂）製のインシュレ−タは、融点が３５０℃以下とし、これであれば成形を行う射出成形機などの熱負荷が少なく大量生産に問題が少ない。また、結晶化潜熱が１０Ｊ／ｇ以下とすると熱可塑射出成形機の金型の中で樹脂が固化する際の発熱を抑えることが出来、結晶化潜熱が倍以上のＰＰＳに比べ良いし、この結果、金型に対する熱負荷が減らせるので金型寿命に対して有効であり，製造設備が簡単になり量産が容易になる。
また溶融時の生成ガス量が２００ｐｐｍ以下(融点＋30degの範囲)とすることにより金型の腐食をも抑えることが出来都合が良い。また、インシュレータの強度上から炭素繊維、ガラス繊維、炭化珪素繊維、芳香族ポリアミド繊維、チタン酸カリウムウィスカ−繊維、アルミナ粉、シリカ粉、硫化モリブデン粉、黒鉛粉のうちの少なくとも１つから選ばれる無機充填材を９５重量％以下含有するものであって、１０乃至５０重量％含有するものが使い易い。このような樹脂には耐熱性や熱伝導性、あるいは費用的な問題からは充填材の含有率を増やすのが良いがあまり入れすぎると脆くなるなどの問題もあり１０乃至５０重量％含有するものが適当で、更に望ましくは３０−４０重量％程度を選択する。更にステアリン酸系金属塩の滑剤を添加しないか、３．０重量％以下添加した液晶ポリエステル成形品であり、コイルを直接巻装される巻枠部と、固定子の内径または外径側に配置される壁部と、その壁部には巻線の結線を行うための端子箱とを備え、内径または外径側の壁部の金型分割面近傍にサイドゲートを設け、ゲートサイズを１．２ｍｍ□以下とし、ゲ−トを凹形状部に設けている。固定子ティース部を覆い巻線が巻装される絶縁材の巻枠部の表面粗さを１０μｍＲｚ以下としている。
【００２３】
ここでいう液晶ポリマ（ＬＣＰ）とは、液晶構造を発現する高分子で、溶融時に分子が配向して流動しない固体と、分子が配向せずランダムな状態で流動する液体との中間状態となるもので、溶融時にこの液晶性を示す樹脂であれば流動性が良く射出成形が容易になる。本発明の液晶ポリエステル樹脂はベンゼン環類を有するモノマーをエステル結合で繋いだ全芳香族の主鎖型タイプで、この剛直鎖の配向により耐熱性や強度特性が得やすい。この樹脂に無機充填材を３０又は４０％混合し、２９０゜Ｃの融点で溶解時の生成ガス量が１５０ｐｐｍ／ｇ以下のものを成形に使用する。
【００２４】
図３は液晶ポリエステル樹脂とＰＰＳとの特性比較を示す図であって、樹脂として液晶ポリエステル樹脂（ＬＣＰ）は成形条件の変更を含め６種類と、参考用の従来例であるポリフェニレンサルファイド（以下ＰＰＳ樹脂）を記載する。無機充填材はガラス繊維の充填量である。滑剤は射出成形時に金型から成形樹脂を外しやすくする離形材で、樹脂成形品を金型から外す時に抵抗が大きいと、樹脂が変形したり、かじりが発生するなどの問題が起こる。樹脂に含めるものと金型に吹きつけるものなどがあるが本発明の場合固化時の収縮が均一で樹脂自体の剛性が高いので離形しやすく離形材はほとんど使用しなくとも良いが、成形装置の軽量不安定を解決するため一部に内部離形剤を使用し、どのような成形装置のスクリュー形状でも使用できるようにしている。
【００２５】
図３の抽出量とはオリゴマ抽出量であって、高分子化合物は一般に分子量一万以上で規則的繰り返し構造を有しこの繰り返し数である数十から数百程度を重合体というが、この内、重合体が２０程度までのものをオリゴマといい、このような低分子成分が冷媒や冷凍機油中に溶出してくる量のことである。オリゴマ抽出量が多いと冷媒回路中の低温部で析出し冷媒回路を詰まらせる原因となる。又熱可塑性樹脂は過熱すると溶融するが、融点はこの溶融温度で、この融点は、例えば示差走査熱量計（ＤＳＣ）等で計測する。結晶化潜熱は、やはりＤＳＣなどで溶融させた樹脂を一定速度で冷却降温したときに結晶ピークの面積から熱量を求めるもので、溶融後に固化する結晶性の樹脂はある温度で結晶化しこの時発熱するこの発熱量を言う。この発熱量が多いと冷却に時間がかかり、成形に時間がかかる。又熱可塑性樹脂は溶融時に微量ガスを発生する。これは樹脂製造段階で重合などが不充分で残留する未反応成分、末端基の反応による副生成物、不純物などが要因であったり、樹脂自体の微量熱分解で発生し、温度が高ければガス量も多くなる。このガス量が多いと金型へのスラグなどの付着も多くなり、腐食や摩耗が増加する。溶融時の生成ガス量によっては金型の腐食や摩耗で金型寿命が短くなる。
【００２６】
保圧とは射出した後冷却を行うまでの圧力を保つ時間でこれが極端に長いと成形サイクルが長くなってしまい、量産時に問題となる。グリセリンＢＤＶ値とは電線の絶縁層の絶縁耐力を測定する方法で、グリセリン溶液中に浸漬させた電線に電圧をかけ絶縁破壊する電圧、break Down Voltageを測定するもので、この電圧が高いほど絶縁信頼性が高く、特に低い部分があるとそこを基点としたレアーショート発生の原因となる。電動機の巻線はその巻線工程で冶具やノズルなどに電線が接触し絶縁皮膜は傷がつくし、巻線が直接巻回されるインシュレーター５の表面粗度が粗いと電線皮膜にも劣化などの影響がある。成形の際保圧を行う。樹脂が固化時に収縮しこの時縮や凹部など，ヒケを発生しやすい。この時射出する樹脂にシリンダーを回転させて圧力を掛けつづけ，即ち保圧により樹脂の充填量を確保してヒケを防止する。保圧が低い場合は表面粗度も大きくなり絶縁の信頼性を考えた表面粗さ１０μｍＲＺをこすのでＰＰＳ樹脂を成形する時の保圧より大きくすることが望ましい。この保圧をかけて金型の表面の形状を樹脂に移す金型転写性を良くすることが出来，成形後の樹脂の表面粗度が上がる。図３は、このＬＣＰ樹脂による効果を検証した結果でバリの有無や巻線の電圧破壊値などの信頼性評価や成形時の条件選択が得られている。
【００２７】
図３に示す様に、供試樹脂は、比較用としてＰＰＳ樹脂が１種、ＬＣＰ樹脂が２種類であるが、ＬＣＰは成形条件（保圧）をそれぞれ３条件、と２条件に振って計６種について検証を行った。ＬＣＰ樹脂は溶融粘度が低いため、成型機スクリュ−仕様によってはスクリュ−溝への食い込みが悪く、計量が安定しないことがある。これを防止する目的で滑剤を少量添加することがあるが、ＬＣＰ−１ｃには脂肪酸アミド系の添加剤を、ＬＣＰ−２にはステアリン酸系の添加剤をそれぞれ０．３ｗｔ％添加している。図３の各樹脂の成形品を粉砕して、クロロホルムによるソックスレ−抽出試験によりオリゴマ抽出量を評価した。ＬＣＰ−１は抽出量がＰＰＳ樹脂の半分であり、ＬＣＰ−２は添加剤を添加している分ＬＣＰ−１より抽出量は増加するが、それでもＰＰＳ樹脂と同等であり、ＬＣＰ樹脂は冷媒回路中の圧縮機に使用しても抽出物が冷凍回路を詰まらせるような不都合はなく、信頼性に優れることが分った。
【００２８】
次いでＤＳＣにより各樹脂の融点を測定したが、いずれの樹脂も約２９０℃であることから、通常の射出成形機の耐熱性で十分対応可能である。またＤＳＣにより結晶化潜熱を測定した。これは結晶性樹脂が溶融状態から固化するまでの間に発生する熱量を表すもので、この値が大きい場合は金型に保持して冷却する時間が多く必要で、この値が小さい場合は、容易に固化するので冷却時間は極短時間で良いことになる。この結果から、ＬＣＰ樹脂は結晶化潜熱が３Ｊ／ｇ以下と非常に小さいため冷却時間を短くしたハイサイクル成形が可能である。そして、各樹脂の溶融時の生成ガス量を測定したが、ＬＣＰ樹脂はＰＰＳ樹脂に比べて生成ガス量が少なく、腐食性の硫黄成分も含んでいないため、金型メンテナンス頻度を減らせ、金型の長寿命化をはかれるというメリットを有している。
【００２９】
次に各樹脂を同一の金型・成形機を用いてインシュレ−タ形状に成形し、ティ−ス端面に対向する巻枠頂部における、表面粗度を測定した。続いてインシュレ−タをティ−スに挿入し、例えば巻線は線径φ1.1を用て実際に巻線を施した後、１タ−ンづつ巻き解き、巻線のグリセリン中でのBDV値を測定することにより巻線の被膜へ与えるダメ−ジを検証した。この結果から同等保圧条件下ではＬＣＰ樹脂はＰＰＳ樹脂に比べて金型転写性が若干劣り、成形品の表面粗度が低く、巻線被膜へのダメ−ジも表面粗度に比例して悪い結果であった。しかし保圧圧力を上げて成形することにより、表面粗度が向上し、巻線被膜へのダメ−ジを少なく出来ることが分った。つまりインシュレ−タにＬＣＰ樹脂を用いて、巻線が巻装される巻枠部の表面粗度を10μmRZ以下とすることで、巻線被膜へダメ−ジを与えず、絶縁信頼性を確保できる。
【００３０】
図４，図５，図６は固定子ティース軸方向に２分割し、ティース３の軸方向端部からそれぞれティーすに差し込まれるインシュレ−タ５の構造を示す。図４，図５はインシュレータ５の半分を示し，ほとんど図４，図５と同一形状のインシュレータ５を反対側の軸方向端部から差し込み突合せ部を一部重ね合わせる構造。にして巻線を俵巻になるように巻くことにより鉄心との間の絶縁を構成できる。図４の左側にはバックヨーク２の方から見た平面図を，右側にはその側面図を記載しており，回転子側の内径側壁９ａとヨーク側の外形側壁９ｂの間に電線を巻く巻枠８が示されている。この図４を上から見た図が図５の上部側の図で，回転子側から見た図が下部側の図である。インシュレータの軸方向端部には端子箱１０が一体成形されており，インシュレ−タの内壁９ａの根本近傍に軸方向に設けた段差１３を有し，この段差１３の凹部にゲ−ト１１を設け、ゲ−トのサイズを１．２ｍｍ□以下としている。即ち内壁９ａの軸方向に段差１３を設けて、段差１３の凹部における金型分割面位置にゲ−ト１１を設けている。この構成によれば、金型を２プレ−ト構造にできるので部品点数を抑えてコストを抑えられる。さらにゲ−トサイズを１．２ｍｍ□以下とし、凹部に設けたため、切り離し性が良好であり、さらにゲ−ト残りがあったとしても凹の部分であるため、内壁の外側端面まで突出せず、内壁対向位置で微小ギャップを隔てて回転する、回転子に接触することがない。なおこの図は各ティ−ス毎に分割したインシュレ−タであるが、各ティ−ス毎に分割せず複数のティースに連続して円環状や円弧上の一部で繋がった一体形状のものであっても同じ効果を奏する。
【００３１】
図６は円環状の固定子の軸方向に対して上下に２分割したインシュレ−タの巻枠部８の縦断面模式図である。このインシュレ−タ内径壁部９ａに設けた段差の凹形状部における金型分割面近傍の１箇所にサイドゲ−ト１１を設け、２プレ−ト金型で成形を行っている。図６の最上部の巻き枠頂部をとおる中心線の上にこのゲート１１が設けられている。また図６のＤは巻枠部根本の固定子ティ−ス端面に接する部分においてティ−ス直行方向の幅を示し、ｄは巻枠部の先端におけるティ−ス直行方向の幅を示し、金型のＤ寸法はＰＰＳ樹脂と同一とすると、ＬＣＰ樹脂は成形収縮率が小さいため（ＰＰＳ樹脂に比べてｄ／Ｄの値が大きい）、金型からの離型時や、固定子ティ−ス３への挿入時に加わる応力が低くなり、巻枠部根本でのクラックが生じなかった。またＰＰＳ樹脂比べて巻枠８の肉厚を低減できる。さらに巻枠部根本幅を、ＰＰＳ樹脂より小さくしても応力が増加しないため、固定子ティ−ス３とのクリアランスを小さくできる。すなわち巻線行程における巻線張力と巻線機振動によるインシュレ−タ５のブレ量が減り、巻線の整列性の向上、すなわち占線率を向上させられるので、電動機効率が向上するという良好な結果が得られた。
【００３２】
図７は集中巻型電動機の固定子コアの製造方法について説明する。まず、図７（ａ）に示すような２種類のコア片２０ａ，２０ｂをフレす加工，即ち打ち抜きで形成する。例えば、磁性材料をプレス打ち抜きして２種類のコア片２０ａ，２０ｂを形成する。このコア片２０ａ、２０ｂには連結部２２として、表面に凸部を裏面に凹部をそれぞれに設けている。
【００３３】
次に、図７（ｂ）に示すように２種類のコア片２０ａ，２０ｂを積層する。積層は次のように行なう。まず、同じ種類のコア片２０ａを複数個の直線状（帯状）に配列することによりコア部材２１ａを形成する。次に、コア部材２１ａの上に他の種類のコア片２０ｂを帯状に配列して層を形成する。この時、コア片２０ｂの裏面の凹部がコア片２０ａの表面の凸部に嵌合するように積層する。すなわち、積層方向に相隣るコア片の凸部と凹部とが嵌合される。さらにコア片２０ｂからなるコア部材２１ｂの上にコア片２０ａを帯状に配列する。この時もコア片２０ａの裏面の凹部がコア片２０ｂの表面の凸部に嵌合するように積層する。このようにコア片２０ａからなるコア部材２１ａとコア片２０ｂからなるコア部材２１ｂとを互い違いに積層していき、固定子コア１２を形成する。
【００３４】
このように形成された固定子コア１２は、コア片２０ａ，２０ｂにそれぞれ設けられた凸部・凹部の連結部２２を中心に、回転可能となる。その後、この固定子コア１２のティースに絶縁部材としてのインシュレータ５を取り付ける。このインシュレータはＬＣＰ樹脂にて成形されたものである。インシュレータ５を取り付けた後、図７（ｃ）の様に、固定子コア１２を直線状（バックヨ−クが水平状態）、またはティ−ス歯先が開くようにバックヨ−クを１８０°以上に展開した状態に保持して、インシュレータ５を介してティース３の回りに巻線４を施す。その後、連結部２２を回転することにより環状に形成する。このようにして最終的に図１に示す固定子を製造する。
【００３５】
この電動機製造方法を採用することにより、巻線性が良く、より高効率な集中巻型電動機を提供できる。尚、この方法では、コア片２０ａ，２０ｂを形成してから、積層する手順で説明しているが、コア片２０ａを形成して積層し、その後コア片２０ｂを形成して積層するというようにコア片の形成と積層を繰り返して行なうことで、固定子鉄心を形成するようにしてもよい。この固定子コアに対して、インシュレ−タをあらかじめ上下分割して、各ティ−ス毎に別ピ−スとして挿入する製造方式では、巻枠部の肉厚１４は、樹脂流動性ら０．５ｍｍが限界でそれより薄い場合は、挿入時や、巻線時の応力により巻枠根本にクラックが生じる。逆に１．５ｍｍ以上の肉厚とすると固定子スロット１６の面積が減るため、電動機の効率が低下する。すなわち巻枠部の肉厚を０．５ｍｍから１．５ｍｍの範囲とすると生産性および効率に優れた電動機が提供できる。
【００３６】
次に、固定子コアを金型にインサ−トして、固定子ティ−スを覆うようにインシュレ−タを一体成形する場合について説明する。この方式によれば、あらかじめ上下分割したインシュレ−タを、各ティ−ス毎に別ピ−スとして挿入する方式に対して、固定子ティ−スとインシュレ−タのクリアランスはほぼゼロとなる。
さらにガタ付きによる巻線性に乱れがないため、占積率が向上する。さらにインシュレータ毎にティース部に挿入する挿入行程がないため生産性が優れ、挿入時の応力による巻枠根本のクラック生成がないので絶縁特性を満たすためだけの最低限の巻枠肉厚とすればよいので、占積率を向上させられる。巻枠の肉厚としては、巻枠肉厚は０．２ｍｍあれば絶縁特性を満たせることが出来る。逆に肉厚が１．５ｍｍを越える固定子スロット１６の面積が減るため、電動機の効率が低下する。すなわち巻枠部の肉厚０．２ｍｍから１．５ｍｍの範囲とすると生産性および効率に優れた電動機が提供できる。この様に固定子に一体に成形された絶縁成形体５は巻線時に余計な応力が加わることも無く，即ち絶縁と鉄心との間に隙間など応力の高くなる要素が存在しないため０．２ミリメートルの厚み以上であれば問題ないし，巻き枠の形状を鉄心形状にフィットさせて一体に出来、更に薄い形状を製造しやすいので、各種絶縁仕様やサイズ，形状など巻線の違いを考えても１．５ミリメートルよりも薄いもので良く、高々０．９ミリメートルの厚みがあれば巻線作業上も問題点は無くなると判断される。
【００３７】
図８は固定子のバックヨーク部２、複数のティース部３、当該複数のティース部間を繋ぐ連結部２２を有し、当該連結部２２において折り曲げ可能なコア12の巻線方法説明図で、図８ａはこの固定子を金型にインサ−トしてバックヨ−ク２と巻線４との絶縁を行うウェッジ１５を、ティ−ス３の歯先と平行方向に薄肉形状にインシュレ−タ５ともに一体に成形する行程を示し、図８ｂは連結部２２を可動させ各ティ−ス３先端側を開いてバックヨ−クを１８０°以上に展開した後に樹脂を加熱させた上で冶具等の機械的手段等用いてウェッジ１５をティ−ス直角方向に変形を加え、その後ティ−ス３に直接巻線を行う工程を示し、図８ｃは巻線後に、変形させたウェッジ１５を前記と同等方法により再度ティ−ス３直角方向に戻す工程を示し、展開したティ−ス３は連結部２２を可動させて最終的に図１に示すような環状とする。この方式によれば、絶縁紙やシ−ト状絶縁樹脂等をティース間絶縁として挿入することなく固定子バックヨ−ク部２と巻線４との絶縁を確実にできるので、部品点数の削減ができる。
【００３８】
図９はインシュレータ５を固定子コア１２に挿入する工程を説明する説明図である。図８ａの様に巻線が無い状態でコアに挿入されるので簡単な作業で行える。以上のような製造方法で製造される電動機は、電動機の低振動、低騒音化のためには電動機のスロット数および極数を多くすることが有効である。従来の集中巻式電動機は巻線占積率が低いため、極数を多くするのに限界があったが、本発明の集中巻式電動機は固定子スロットの占積率を高くできるので、スロット数および極数を多くしても効率の低下がないため、４ヶ以上の極数、より好ましくは６極とする事が可能で、小型で、性能が良いものが得られる。
【００３９】
図１０は射出成形装置５０の金型装置中でインシュレータ５を成形している状態を説明する説明図で，金型装置は固定金型３７と可動金型３６よりなる。図示していない射出成形装置から注入された上記で説明した樹脂の溶融品を、金型内の樹脂流動路であるスプルー３４、ランナー３５を通してゲート１１から成形品５の形状を決めている金型内の空間へ供給される。固定金型と可動金型の境界である金型分割面はランナーと接続するゲート１１の存在する面であり，この結果２プレート金型と出来るので部品点数の少ない製造装置が得られる。しかも３プレート金型機に比べ成形サイクル時間が短くなり大量生産にも有効である。もちろん３プレート金型など多くのプレートを有する金型にすればより複雑な形状やゲートを壁部先端に設けるなどゲート位置を自由に選択できる。
【００４０】
図１１に射出成形装置全体を説明する説明図を示す。射出成形機は計量されて一定量が決められた樹脂のペレットや粒体を投入するホッパー３８から供給されたシリンダー３９内で樹脂を溶融させスクリュー４０で金型装置の方へ押し出す。射出成形機から固定金型３７に押し込まれた溶融樹脂はスプルー３４などの流道路から成形品６０の空間へ注入される。可動金型３６は固定盤４２に対し固定金型３７の方向へ駆動されて金型装置が一体となり，型締めが行われた後でこの樹脂の注入が射出されて行われる。樹脂注入後保圧され、冷却されて固化した後で可動金型３６が固定盤４２の方向へ成形品を固着したままゲートで破断して引き剥がされる。又後射出成形機も可動盤４１により固定金型３７から引き離される。成形品はピンにより可動金型から押し出されて取り出すことが出来る。
【００４１】
射出成形は以上の様に、計量，型締め，射出，保圧，冷却，離型，製品取出し，の工程で１サイクルが構成される。第１サイクルの冷却工程中に第２サイクルの計量が開始されるので計量時間は射出成形サイクルに入れないとすると、型締めから製品取出しまでが１サイクルの時間となる。方締めと取り出し時間は成形装置能力と金型構造に依存するので、射出，保圧，冷却時間が樹脂特性に依存する。既に述べてきた様に，本発明のＬＣＰ樹脂を使うことによりこのサイクル時間を短縮でき，且つ，冷却などに大掛かりな成形装置を使わなくとも済み，簡単に量産が可能になる。
【００４２】
以上のとおり，図１０に示す装置で製造されるインシュレータ５は、ティース軸方向に分割したもので，巻線が巻かれる巻枠８と巻き線４がティース直角方向に線漏れするのを防止するため軸方向延長方向のコイルエンドに対向する位置に設けられた内径壁又は外形壁９ａ，９ｂより構成され，外形壁部には巻き線の結線を行うための端子箱１０が設けられる。内径壁部には図５に示す様に１−２ミリメートル程度の段差１３を設けこの引っ込んだ部分に１．２ｍｍ角より小さな面積のゲートを設けて、熱可塑性の液晶ポリエステル樹脂により成形されたものである。成形にあたっては金型分割面を図１０の如くインシュレータ５の巻枠部８が固定子ティース端面に接する面で、巻き枠頂部の裏側の面と同一面で，ゲート１１の近傍に設ける。固定金型３７側にインシュレータ５の内外径壁部，巻枠頂部の形状をしたキャビティおよびランナー，ゲートを形成し，可動金型３６側には巻枠部の頂部より下側の形状のキャビティを形成させる。これにより樹脂の注入をスムースに行え，且つ，製品の成形と離型が簡単に行える２プレート金型で樹脂成形品を製造できる。なお金型装置の場合大きな射出圧力が金型に作用するため，この力に耐える様に油圧やエアー圧により型締めを行う。
【００４３】
金型のキャビティ内部に樹脂が充填された後冷却・固化によりインシュレータ５が形成される。次に型開きを行い可動金型に埋設されたイジェクトピンを突出させることにより製品およびランナ―から金型を取り出す。この際にイジェクトピンを製品側の巻枠頂部裏側の面とランナー部双方に設けて、ランナー側ピンにアンダーカット部を設け，ランナー側だけ保持しインシュレーたー成形品より離型を送らせて、即ちピン突出のタイミングをずらして製品をランナーより若干早め可動金型から切り離すことによりゲートへの力をあまりかけずにランナー３５をゲート位置で切り離す工程を省略することが出来る。これによりゲート切り離し工程が不要になるだけでなく，ゲート切り離し後のゲート残りを短く抑えることが可能になりこのゲート残りが段差の凹部から突出せず、ゲート処理も不要に出来るので工程が簡素化でき生産性に優れた生産方式とすることが出来る。
【００４４】
以上の様に、固定子を形成する鉄心に直接巻装され通電されるコイルである巻線とヨークやティース間に設けられ絶縁を行う絶縁部材を、繊維状無機強化材もしくは無機充填材を含有する本発明の液晶ポリエステル樹脂を金型に注入して樹脂成形品を成形して製造する際、この液晶ポリエステル樹脂は融点が３５０゜Ｃ以下、融解時の生成ガス量が２００ｐｐｍ以下であって、結晶化潜熱が１０Ｊ／ｇ以下のものを前記金型に注入して熱可塑性射出成形するので、射出から成形品取出しまで簡単で早い電動機の製造方法が得られる。更に樹脂成形品のコイルの軸方向端部であるコイルエンドに対向する部分であって内径側もしくは外径側の壁部先端又は壁部根元部の成形品凹部に設けたゲートから液晶ポリエステル樹脂を注入するのでゲート処理工程なども省略できる。なお上記説明は内径側壁面に凹部を設け個々にゲートを持ってくる形状の説明をしたが外径側壁面の端子箱などの凹部であっても良いし，更に、固定子の内側に回転子を回転させる構造の電動機にて説明してきたが、アウターローター，即ち固定子を中心側に設け外側に回転子を配置する構造でも同様な形状，製造方法が可能であることは当然である。
【００４５】
図１２，図１３は本発明の液晶ポリエステル樹脂を使用した射出成形により成形品を製造する別の成形装置の構成を説明する説明図である。即ち固定子１を形成するヨーク２の内周または外周方向に突出した複数ティース部３を有する鉄心と、このティ−ス部３に直接巻装され通電されるコイルである巻線４と、コイル４とティース部３間に設けられ絶縁を行う絶縁部材であるインシュレータ５と、を備えた電動機を製造する際，絶縁部材５として、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を金型に注入して樹脂成形品を成形する時に、金型に固定子１をそのまま埋め込み，特にティース部３に直接樹脂が密着して一体となるようにキャビティにこのティースを挿入してから、液晶ポリエステル樹脂を注入し、前記固定子と前記樹脂成形品を一体に成形するものである。
【００４６】
この製造方法では先に図８で説明した固定子１のヨ−ク２とコイル４との絶縁を行うウェッジ１５を、固定子１のティ−ス部３の歯先と平行方向に薄肉形状に金型内で一体に射出成形を行なうことが出来る。このように電動機の固定子を形成する鉄心ティース部に直接巻装され通電されるコイルと鉄心間に設けられ絶縁を行う絶縁部材を形成するように、繊維状無機強化材もしくは無機充填材を含有する液晶ポリエステル樹脂を注入して樹脂成形品を成形する金型の場合，固定子の鉄心部分を覆うとともに、ティース部３の周囲にキャビティを設け，このキャビティを覆う様な構成としている。
【００４７】
図１２は金型の正面図で，図１３は金型の側面図である。射出成形機のノズル５１は固定盤４２と接触しては樹脂を射出し，終わると離れる構造で，固定盤４２からランナーストリッパー５２，固定金型３７に設けてある溶融樹脂の流路であるスプルー３４，ランナー３５を経由してゲート１１からキャビティに樹脂が注入される。成形時は固定金型３７に型締めされ一体にキャビティを形成する可動金型３６はスライド金型３６Ａとスライド金型３６Ｂが可動盤４１にも受けられ記載していないインジェクションピンとともに、固定金型に型締め，型開きし、成形品を取り出す構成にしている。
【００４８】
このインシュレータ一体成形金型による製造方法では図８の様に、先ず各ティース部を連結する連結部２２により展開自在に稼動させてバックヨーク２を水平状態とする。図１２の金型装置が型開きの状態で可動盤４１にバックヨークを図の下側にして固定子コア１をスライド金型３６Ｂの所定位置に固定する。このスライド金型Ｂは少なくとも１対設けられ例えば一方を固定し，他方を横方向にスライドさせてヨークを設定された位置である一方へ押し付けて両側から抑えこむ。次に固定子コア１の軸方向両端面を絶縁材５の空間を介して覆うスライド金型３６Ａも軸方向両側からスライドさせ固定子スロット部に挿入し，固定子スロット中央部で付き合わせる。ついで可動盤４１、スライド金型３６Ａ，３６Ｂの可動金型をを油圧やエアー圧にて駆動し固定金型に固定し、ランナーストリッパープレート５２，固定盤共々型締めを行い，各方向における圧力を成形時の樹脂圧力以上の圧力で保持する。こうして固定子コア，スライド金型３６Ａ，３６Ｂおよび固定金型によりインシュレータ形状で樹脂が注入される空間であるキャビティが形成される。
【００４９】
続いて射出成形機のシリンダーノズルを固定盤の溶融樹脂入口であるスプールブッシュに接触させて液晶ポリエステル樹脂を射出する。スプルー３４，ランナー３５，ゲート１１を通過した溶融樹脂はキャビティ内に流動して金型内の配管に通水するなどの冷却を行い，樹脂を固化して固定子コアとともにインシュレータ５を一体に成形させる。本発明のように流動性の良い樹脂を使用するが，更に加えて，ゲートは各ティース毎にインシュレータ内壁部分に例えば１ヶ所設け，樹脂流動長さコア積層厚さの半分とし，樹脂が射出され流動中に固化してショート不良となるのを防止している。図に示す様にスライド金型３６Ａ，３６Ｂの間や固定金型とスライド金型間にウエッジ１５のキャビティを設けることにより成形時にインシュレータ５と一緒にウェッジ１５をどのような形状、例えば部分的に薄くするなどしても成形できる。なお図８の説明ではウェッジ位置を外径壁側だけに設ける構造を説明したがこの様に内径壁側にも簡単に設けることが出来る。
【００５０】
この様に、固定子のバックヨーク部、複数のティース部、複数のティース部間を繋ぐ連結部を有し、当該連結部において折り曲げ可能な固定子鉄心とし、固定子鉄心を金型装置にインサートして絶縁樹脂と一体に成形することにより、固定子ティース部の軸方向において巻線が巻装される面の絶縁材成形品の肉厚を０．３から０．９ｍｍとすることが出来，さらに一層効率が良く信頼性の高い電動機を製造することができる。
【００５１】
なおウエッジ１５を有する構造の場合の製造では，先ずバックヨ−クと巻線との絶縁を行うウェッジを、ティ−スの歯先と平行方向に薄肉形状に金型内で一体に射出成形を行う工程と、連結部を可動させ各ティ−ス先端側を開いてを水平方向以上に展開した後に樹脂の熱変形温度以上に過熱させるか、冶具等の機械的手段を用いてウェッジをティ−ス直角方向に変形を加えてからティ−スに直接巻線を行う工程と、巻線後に変形させたウェッジを前記と同等方法により再度ティ−ス直角方向に戻し、展開したティ−スを間接部を可動させて環状とする工程による作業により製造することが出来る。
【００５２】
上記は連結部２２を有し展開可能な固定子を水平方向に伸ばしてから射出成形したが，円環状の固定子を金型にインサートして絶縁樹脂と一体に成形することも可能であり，これにより固定子ティース部を覆い、ティ−ス部の軸方向において巻線が巻装される面の絶縁材成形品の肉厚を０．３から０．９ｍｍと薄い絶縁にすることが出来る。水平展開状態で巻線を巻く作業では無理な力をかけることなく簡単な作業のため絶縁の厚みは絶縁耐力だけで決めることが出来０．２ｍｍ以上とより薄く出来るが，円環状固定子にコイルを巻く作業には巻線機の複雑な作業により力の方向が変わるなど絶縁に加わる負担を考え０．３ｍｍ以上の薄さが必要である。
【００５３】
別の金型装置の説明を図１６乃至図１９にて示す。図１６は型締めしている金型装置のキャビティにインシュレータ５が成形機ノズルより射出された溶融樹脂が固化している状態を示す。射出された溶融金属は溶解プラスチックを移送する経路７１を通りランナー３５からゲート１１を介し金型本体の型板に角穴又は丸穴を掘り込み穴に嵌めこまれたコア入れ子７４、７５のなかに設けられたキャビティに充填され固化されてインシュレータ５となる。この時途中の通路にもスプルー３４やランナー３５の如く溶融金属が充填されて固化する。この状態ではエジェクタープレート下７９に埋設されたロック押だしピン８２は，頭部の下方にクリアランスｄを設けている。エジェクタープレート上下７８、７９が、成形機の動力を伝達するシャフトであるエジェクターロッド８１により上昇した時に、このクリアランスｄの距離まで押だしピン８２は動作しない。そのため同じくエジェクタープレート７８、７９により押し出されるエジェクターピン７７に比べランナーロックピン７６は動き出しが遅くなり動作タイミングが遅れることになる。即ちランナーロックピン７６はエジェクターピン７７とは時間差を置いて動作することになる。また型開きの時ランナーを可動側にひきつけスプールブッシュからスプールを引き抜くとともに製品とランナーをゲート１１で切り離す役目であるランナーロックピン７６を押し出してランナー３５を金型から取り出す役割であるロックピン押だしピン８２の上部は図１６Ｂ部詳細に記す如くランナー３５のアンダーカット部にはまり込む形状をしている。ランナーに食い込み可動側固に保持されるようであればアンダーカットで無くとも良い。エジェクタープレート７８，７９は押し出し装置が可動するためのスペースを造るスペーサーブロック８０の範囲内で動くことが出来る。
【００５４】
図１７は図１６から金型が開く工程を説明する図で、可動金型が成形機の動力により下のほうへ開く型開きを示している。金型の可動側と固定側が切り離されることにより溶融金属が固化した樹脂成形製品であるインシュレータ５，ランナー３５，スプルー３４などはそのまま可動側金型に接着した状態で残り，固定側から離型される。
【００５５】
図１８は可動側金型から成形品を離型させる動作を説明する図で，離型のため製品突き出し動作を油圧などにより駆動されるエジェクタロッド８１が行う。このエジェクタロッド８１がエジェクタプレート７８、７９を固定側へ動かしエジェクタピン７７が成形品５を金型から先ずクリアランスｄ寸法だけ押し出す。この時ランナー３５はランナーロックピン７６により保持されているので、製品５とランナー３５はゲート位置で自動的に切断される。先に説明した様にゲートを１．２ｍｍ角以下としているので、ピンによる押し出しのみで容易に成形品とランナーは切断される。逆にいうと寸法ｄはこの切断を行える寸法以上にすれば良い。図１９は製品およびランナー他を取り出す説明図で，エジェクタープレート７８，７９が更に上昇するとゲート位置で切断されたランナーはロックピンにより金型から押し出されるので簡単に取出しが可能となる。この様に射出成形製品と金型内の経路などの溶融固化品であるランナーなどとは離型に時間差を持たせることにより成形サイクルが簡単になる。当然製品も金型から押し出され、ロボットアームによりチャックして取り出せる位置に着た時に製品と，スプルーをつけたランナーは同時に取り出しが可能となる。このような構成により簡単で短時間の射出成形サイクルを行うことが出来る。
【００５６】
図１４にてＰＰＳ樹脂とＬＣＰ樹脂の成形サイクルの比較を説明する。先に説明した様に成形サイクルは型締め，射出，保圧，冷却，離型、製品取出しの各工程での作業が行われるが，本発明の液晶ポリエステル樹脂では結晶化潜熱が大幅に小さく，結晶化樹脂は冷却時の固化するまでの熱量が小さいので発熱が小さく冷却時間が大幅に低下していることがわかる。他の工程は大差ないとしても金型の冷却が早く成形サイクルが大幅に短く出来るので製品が短時間で得られ，簡単に量産が可能となる。以上の様に本発明は、高効率、且つ、信頼性が高く大量生産が可能な電動機が得られる。更に製造サイクルが短く大量生産に適した電動機の製造方法を得ることが出来る。更に簡単な構成で寿命の長いこの電動機の金型装置となるものである。
【００５７】
図１５には本発明の電動機を冷凍サイクルにおける圧縮機に使用した場合の冷媒回路図を示す。図は圧縮機３０、蒸発器３１、凝縮器３２、絞り３３から構成される冷凍回路を示し、圧縮機３０は密閉構造の容器の内部に圧縮機高部を駆動する電動機が内蔵されており、本発明の集中巻式電動機を搭載している。この冷媒回路では圧縮機で圧縮され高温高圧のガス冷媒とされ、凝縮機３２で冷媒の温度が低下し液体化した後で、絞り３３で圧力が低下し，蒸発器で蒸発してほぼガス状態となって再び圧縮機に戻されるが、内蔵された電動機にはこのような冷媒や圧縮機構などを回転させるなどの潤滑油が常に浸漬された状態となる。この回路内に冷媒、冷凍機油を内包し、冷媒としてジフルオロメタン、１，１，１，２，２−ペンタフルオロエタン、１，１，１，２−テトラフルオロエタン、１，１，１−トリフルオロエタン、クロロジフルオロメタン、二酸化炭素、アンモニア、ジメチルエ−テル、プロパン、ブタンのうち少なくとも一種と、冷凍機油として、エステル系、エ−テル系、グリコ−ル系、アルキルベンゼン系、ポリαオレフィン系、ポリビニールエーテル系、ナフテン系鉱油、パラフィン系鉱油のうち少なくとも一種とを組み合わせて使用したても、運転中の温度や圧力の状態でこれらの冷媒や潤滑油により電動機の絶縁物が影響を受けても、本発明の電動機ではスラッジ生成等の問題を起すことなくによる回路閉塞がなく長期信頼性に優れる冷凍空調機を得ることが出来る。更に本発明の電動機の回転子に、燒結永久磁石またはプラスチック系のフェライト永久磁石又は希土類永久磁石が用いられた場合でも冷媒や冷凍機の影響が無く、且つ電動機の効率がより高くなり，絶縁性能を確保でき，信頼性が高い電動機や冷凍空調装置が得られる。
【００５８】
以上の様に本発明の電動機は、積層鋼板により形成される円環状バックヨークと当該バックヨークの内周または外周方向に突出した複数ティース部を有する鉄心と、ティ−スとティ−スに直接巻装されるコイルと、このコイルとティースとの絶縁を行う絶縁部材（インシュレ−タ）から構成された固定子を有する集中巻式電動機において、絶縁材が、ＤＳＣにより測定される融点が３５０℃以下、結晶化潜熱が１０Ｊ／ｇ以下、溶融時の生成ガス量が２００ｐｐｍ以下(融点＋30degの範囲)、炭素繊維、ガラス繊維、炭化珪素繊維、芳香族ポリアミド繊維、チタン酸カリウムウィスカ−繊維、アルミナウィスカ−繊維等の繊維状無機強化材、もしくはシリカ粉、硫化モリブデン粉、黒鉛粉等の無機充填材のうちから選ばれる少なくとも１つを９５重量％以下含有し、滑剤を添加しないか、ステアリン酸系または脂肪酸アミド系の滑剤を３．０重量％以下添加した液晶ポリエステル成形品であり、信頼性が高く製造が簡単である。
【００５９】
又本発明では、絶縁材はコイルを直接巻装される巻枠部と、固定子の内径または外径側に配置される壁部と、その壁部には巻線の結線を行うための端子箱を備え、内径または外径側のいずれかの壁部にサイドゲ−トを設け、ゲートサイズを１．２ｍｍ□以下としており結線も簡単で、見栄えの良いものが得られる。
【００６０】
また、固定子ティース部を覆い巻線が巻装される絶縁材の巻枠部の表面粗さを１０μｍＲｚ以下としたので絶縁信頼性が高い。
【００６１】
また、円環状の固定子の軸方向に対して上下に２分割した絶縁材成形品を挿入し、固定子ティース部の軸方向において巻線が巻装される面の成形品肉厚を０．５から１．５ｍｍとし、内径または外径側の壁部に段差を設けて、段差の凹形状部における金型分割面近傍の１箇所にサイドゲ−トを設け、２プレ−ト金型で成形したので、製造装置が簡単で安価となる。
【００６２】
また、固定子のバックヨーク部、複数のティース部、当該複数のティース部間を繋ぐ連結部を有し、当該連結部において折り曲げ可能な固定子鉄心とし、各ティース部に対して一対の上下分割された絶縁材成形品を挿入し、固定子ティース部を覆い、ティ−ス部の軸方向において巻線が巻装される面の絶縁材成形品の肉厚を０．５から１．５ｍｍとし、内径または外径側の壁部に段差を設けて、段差の凹形状部における金型分割面の１箇所にゲ−トを設け、２プレ−ト金型で成形したので，効率の良いモーターを生産性良く生産できる。
【００６３】
また、円環状の固定子をインサートして絶縁樹脂と一体に成形し、固定子ティース部を覆い、ティ−ス部の軸方向において巻線が巻装される面の絶縁材成形品の肉厚を０．３から０．９ｍｍとすることにより、高効率な電動機とすることができる。
【００６４】
また、固定子のバックヨーク部、複数のティース部、当該複数のティース部間を繋ぐ連結部を有し、当該連結部において折り曲げ可能な固定子鉄心とし、固定子鉄心をインサートして絶縁樹脂と一体に成形し、固定子ティース部の軸方向において巻線が巻装される面の絶縁材成形品の肉厚を０．２から０．９ｍｍと出来，一層効率を改善できる。
【００６５】
また、バックヨ−クと巻線との絶縁を行うウェッジを、ティ−スの歯先と平行方向に薄肉形状に金型内で一体に射出成形を行う第一の工程と、連結部を可動させ各ティ−ス先端側を開いてを水平方向以上に展開した後に樹脂の熱変形温度以上に過熱させるか、冶具等の機械的手段を用いてウェッジをティ−ス直角方向に変形を加えてからティ−スに直接巻線を行う第２の工程と、巻線後に変形させたウェッジを前記と同等方法により再度ティ−ス直角方向に戻し、展開したティ−スを間接部を可動させて環状とする第３の工程により製造することにより，より信頼性の高い絶縁性能を簡単に得られる。
【００６６】
【発明の効果】
この発明は、上記構成としたので、高効率かつ、生産性、信頼性ともにに優れた電動機が得られる。又信頼性の高い冷凍・空調装置が得られる。又量産が容易で生産性の高い電動機の製造方法が得られる。又信頼性が高くメインテナンスの容易な電動機の金型装置が得られる。
【図面の簡単な説明】
【図１】本発明の実施の形態の電動機断面図。
【図２】本発明の図１のスロット部分を拡大した説明図。
【図３】本発明の実施の携帯における樹脂である液晶ポリエステル樹脂と従来の樹脂であるＰＰＳとの特性比較を示す図。
【図４】本発明の実施の形態におけるインシュレ−タ正面図および側面図。
【図５】本発明の実施の形態におけるインシュレ−タのゲ−ト位置と端子箱を示す図。
【図６】本発明の実施の形態における電動機のインシュレ−タの巻枠の縦断面模式図。
【図７】本発明の実施の形態における固定子の製造方法を示す図。
【図８】本発明の実施の形態における固定子の製造方法を示す図。
【図９】本発明の実施の形態における固定子の製造方法を示す図。
【図１０】本発明の実施の形態における固定子の製造方法および装置を示す図。
【図１１】本発明の実施の形態における射出成形装置を説明する説明図。
【図１２】本発明の実施の形態における製造装置を説明する図。
【図１３】本発明の実施の形態における製造装置を説明する図。
【図１４】本発明の実施の形態における成形サイクル比較図。
【図１５】本発明の実施の形態における冷凍空調機の冷媒回路説明図。
【図１６】本発明の実施の形態における金型説明図。
【図１７】本発明の実施の形態における金型説明図。
【図１８】本発明の実施の形態における金型説明図。
【図１９】本発明の実施の形態における金型説明図。
【符号の説明】
１固定子、２固定子バックヨ−ク、３ティ−ス、４巻線、５インシュレ−タ、６回転子、７永久磁石、８巻枠、９壁部、１０端子箱、１１ゲ−ト、１２固定子コア、１３壁部段差、１４巻枠肉厚、１５ウエッジ、１６スロット、２０ａ，２０ｂコア片、２１コア部材、２２連結部、３０圧縮機、３１蒸発器、３２凝縮器、３３絞り部，３４スプルー、３５ランナー、３６可動金型，３７固定金型、３８ホッパー、３９シリンダ，４０スクリュー，４１可動盤，４２固定盤，５０金型装置，５１ノズル，５２ランナストリッパー、７１溶融プラスチックを移送する経路，７４キャビティ側入れ子，７５コア入れ子，７６ランナーロックピン，７７エジェクターピン，８０スペーサーブロック，８１エジェクターロッド，８２ロック押だしピン。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the technology of electric motors, and for example, relates to a refrigerant compressor and a refrigeration air conditioner using the refrigerant compressor, and relates to an electric motor mounted on the refrigerant compressor.
[0002]
[Prior art]
In recent years, for the motors for compressors of refrigerators and air conditioners, etc., for the purpose of high efficiency and compactness, a concentrated winding stator that winds around one tooth intensively without crossing multiple teeth The adopted motor has been studied, and a resin molded product is generally used as an insulating material between the teeth and the windings.
[0003]
Inside the compressor, a compression element portion for compressing the refrigerant and an electric motor for driving the compression element are built in. In an environment from -20 ° C or lower to higher than 120 ° C, the refrigerant and the refrigerating machine oil are stored and exposed to the mixed liquid. Used while being. The refrigerating machine oil seals and lubricates the compression element portion, mixes with the refrigerant gas and circulates in the refrigerating circuit, and returns to the evaporator and the compressor through a throttle such as a capillary tube. Therefore, when the resin such as the insulating material elutes into the refrigerating machine oil, there is a possibility that problems such as a decrease in the sealing property and lubricity of the compression element portion and a blockage of the throttle portion may occur.
[0004]
Consideration is given to using polyphenylene sulfide (hereinafter, PPS resin), which has high chemical stability such as thermal stability and hydrolysis resistance, and has excellent durability against refrigerant and refrigerating machine oil, as an insulating member of the electric motor inside the compressor. Has been advanced.
[0005]
As shown in Patent Document 1, the structure of a stator and a rotor of a concentrated winding motor of a conventional refrigerant compressor includes a stator, teeth protruding in the inner or outer direction of the stator yoke, and teeth. The windings are wound directly on the rotor, the insulator is an insulating member for insulating the windings from the teeth, and the permanent magnets are embedded in the rotor.
[0006]
The insulator used in this concentrated winding motor is a so-called integral type insulator which is divided into upper and lower parts and inserted into an annular stator and is not divided into a plurality of teeth. In this insulator, a winding frame portion on which a coil is directly wound, a wall portion disposed on the inner diameter or outer diameter side of the stator in the longitudinal direction of the winding frame, and an electric wire are connected to the wall portion. A gate box serving as a resin injection port is provided at the tip of the wall.
[0007]
This insulating member is formed integrally with a resin molded product or a tooth portion as shown in Patent Literature 1 and defines the flexural modulus, flexural strength and dimensions, and has a small amount of oligomer extracted, such as PPS, PA, PBT, LCP and the like are being studied.
The characteristics of the composition of LCP, which is a liquid crystal polyester, are described in Patent Document 2.
[0008]
[Patent Document 1]
JP-A-2001-55979 (Claims 1-3 and 5, Table 1, FIGS. 1 and 2)
[Patent Document 2]
JP-A-10-46009 (columns 0014 to 0018)
[0009]
[Problems to be solved by the invention]
However, even if a PPS resin whose use is considered is used, a resin having a high oligomer content elutes the oligomer component in the refrigeration circuit and precipitates in a low-temperature portion, thereby causing a problem of blocking the circuit. Further, since the PPS resin and the like contain sulfur in the components, a corrosive gas containing sulfur is generated from unreacted components and the like at the time of melting, so that there is a problem that the life of the mold is shortened.
[0010]
The resin used for the molded product is generally a highly crystalline resin, and it is necessary to increase the temperature of the mold at the time of molding and to prolong crystallization time by maintaining the temperature in the mold. There was a long problem. In addition, since these resins are liable to generate burrs, it is indispensable to perform burr treatment of the molded product in order to prevent the refrigerating circuit from being clogged by the separated burrs. When performing burr treatment such as shot blasting, there is a possibility that cracks may occur in the molded product due to stress, and the thickness must be larger than required for the insulation function, and the processing cost and material cost increase. was there. Even if an attempt is made to use a resin such as LCP, there are many problems in mass production for producing a complicated molded product, and there is also a problem that the material cost is high.
[0011]
Also, in the method of inserting resin molded as an insulating material between the stator teeth and the winding into the teeth, if the resin has a large difference in the absolute value of the amount of shrinkage depending on the location, the insertion clearance between the iron core and the resin molded product is not sufficient. It becomes uniform and the clearance of the part with a small shrinkage ratio becomes large, so the winding amount is reduced due to winding disturbance due to winding tension and vibration in the winding process, and the occupying ratio which is the ratio of the winding cross section to the slot area , Ie, the efficiency of the motor is reduced. Conversely, a portion having a large shrinkage ratio has a small clearance or a minus tolerance, and cracks occur in the molded product due to winding tension during insertion into a tooth or a winding process, and the insulating function cannot be satisfied. Therefore, in order to achieve both the efficiency of the electric motor and the dielectric strength, it is necessary to extend the cooling time during molding so as to keep the shrinkage of the resin molded product small, or to increase the wall thickness more than required for the insulating function. There was a problem.
[0012]
Insulating material used in the conventional concentrated winding type motor has a winding portion on which the winding is directly wound, a wall portion provided on the inner diameter or outer diameter side of the stator in the lengthwise direction of the winding frame, an inner diameter or A resin molded product composed of a terminal box portion for connecting windings to an outer diameter wall portion is used, but when a gate serving as a resin injection port is provided at the top of the wall portion, many plates are formed. It is necessary to perform molding with a mold having a configuration, and there is a problem in that the number of mold component parts is large, the mold cost is increased, and the production time is required. As described above, when a highly reliable molded insulator is applied to the structure of the electric motor, there is a problem that it is difficult to manufacture the motor at low cost and mass production.
[0013]
The present invention solves the above-mentioned problems, and proposes an electric motor with high efficiency, high reliability, and mass production. Furthermore, the present invention proposes a method of manufacturing a motor having a short manufacturing cycle and good productivity. The present invention proposes a mold device for the electric motor having a simple structure and a long life. Further, a refrigeration / air-conditioning apparatus with high reliability and high performance is proposed.
[0014]
[Means for Solving the Problems]
An electric motor according to the present invention includes an iron core in which steel plates having a plurality of teeth protruding in the inner or outer direction of a yoke forming a stator are laminated, a coil directly wound around the teeth and energized, and a coil. And an insulating member provided between the teeth portion and the insulating portion to form an insulating member, a connecting portion provided on the core that can be connected to the laminated core by expanding the core and bending the iron core in a circle. A resin which is a molded product having a melting point of 350 ° C. or less, an amount of generated gas at the time of melting of 200 ppm or less, and a liquid crystal polyester resin containing a fibrous inorganic reinforcing material or an inorganic filler to insulate an iron core and a coil. And a molded product.
[0015]
The electric motor according to the present invention includes an iron core having a plurality of teeth protruding in the inner or outer circumference direction of a yoke forming a stator, a coil directly wound around the teeth and energized, and a coil and the teeth. An insulating member provided for insulation; a resin molded product for insulating a teeth portion and a coil by molding a liquid crystal polyester resin containing 10 to 50% by weight of a fibrous inorganic reinforcing material or an inorganic filler forming the insulating member; And the thickness of the insulating member on the surface on which the coil of the teeth portion is wound in the axial direction is 0.3 to 1.5 mm.
[0016]
The method for manufacturing an electric motor according to the present invention is a method of manufacturing a motor, comprising the steps of: winding a winding directly on an iron core forming a stator and an insulating member provided between the iron core and an insulating member; When a polyester resin is injected into a mold to produce a resin molded product, the liquid crystal polyester resin has a melting point of 350 ° C. or less, a generated gas amount of 200 ppm or less upon melting, and a latent heat of crystallization of 10 J /. g and thermoplastic injection molding.
[0017]
The method of manufacturing a motor according to the present invention includes a core having a plurality of teeth protruding in the inner or outer direction of a yoke forming a stator, a coil directly wound around the teeth and energized, a coil and teeth. And an insulating member provided between the parts to perform insulation, and a liquid crystal polyester resin containing a fibrous inorganic reinforcing material or an inorganic filler is injected into a mold so as to form an insulating member. When molding a product, a tooth portion of the stator is inserted into a mold, and then a liquid crystal polyester resin is injected to integrally mold the stator and the resin molded product.
[0018]
The mold apparatus for a motor according to the present invention may be configured such that a fibrous inorganic material is formed between a coil that is directly wound around a core teeth portion forming a stator of the motor and is energized and an insulating member provided between the iron cores for insulation. A mold for molding a resin molded product by injecting a liquid crystal polyester resin containing a reinforcing material or an inorganic filler, wherein the teeth portion of the stator is inserted into the mold, and then the liquid crystal polyester resin is injected. Then, the stator and the resin molded product are integrally formed, and the periphery of the teeth portion is covered.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a concentrated winding motor according to Embodiment 1 of the present invention. FIG. 2 is an enlarged view of the slot section 20 of FIG. In the stator 1, a winding 4 is wound around teeth 3 protruding inside a stator back yoke 2 via an insulator 5.
The stator core 12 is formed in a circular shape, and the winding 4 is inserted with the nozzle of the winding machine from the inner diameter side of the stator core 12 without the rotor 6, and the insulator 5 is moved by moving the nozzle. Is wound directly around the teeth 3. It is wound in a so-called concentrated winding. A rotor 6 having a magnet 7 embedded in an iron core is rotatably arranged inside the stator 1 so as to face the stator 1 and supported by a bearing (not shown). Although the size of the winding 4 in FIG. 1 is made larger than the actual product and is only partially shown for easy understanding, in the present invention, the winding can be densely wound in the groove between the teeth 3. In FIG. 1, the central portion of the winding 4 is not shown, but is actually wound closely. As a result, the area excluding the space for teeth winding insulation and a cut-out (not shown) at the center of the groove can be filled with the winding, so that the space factor of the winding is improved and an efficient motor can be obtained.
[0020]
The insulator 5 is provided to provide insulation between the enamel wire or the winding 4 coated with insulation and the yoke 2 or the teeth 3 of the stator 12. As the insulator 5 used for the compressor, a liquid crystal polyester resin (LCP resin) is used. The LCP resin is a thermoplastic resin obtained by performing a polymerization reaction of parahydroxybenzoic acid (4-HBA) and hydroxynaphthoic acid (2,6-HNA). This LCP resin has better heat resistance and extractability than conventional insulator materials, low melt viscosity during molding and excellent thin-wall flow properties, and a small amount of heat transfer from the molten state to solidification. Has a heat resistance (heat deformation temperature) of 200 ° C. or more, in addition to the property that burrs are generated very quickly and hardly occurs.
[0021]
Therefore, even if the electric motor is used for driving the compressor and exposed to the refrigerant or the refrigerating machine oil under a high temperature and high pressure state and used for a long period of time, reliability can be ensured. As a refrigerant, difluoromethane, 1,1,1,2,2-pentafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, chlorodifluoromethane, carbon dioxide, ammonia , Dimethyl ether, propane, butane, refrigerating machine oil, any combination of ester type, ether type, glycol type, alkylbenzene type, poly alpha olefin type, polyvinyl ether type, naphthene type mineral oil and paraffin type mineral oil And is suitable as an insulator for a compressor motor. Further, the insulator material described in the present embodiment needs to be formed into a thin wall, and this material is effective because it has excellent melt fluidity.
[0022]
The insulator made of the liquid crystal polyester resin (LCP resin) used in the present invention has a melting point of 350 ° C. or less, so that the heat load on an injection molding machine for molding is small and there is little problem in mass production. Further, when the crystallization latent heat is set to 10 J / g or less, heat generation when the resin is solidified in the mold of the thermoplastic injection molding machine can be suppressed, which is better than PPS whose crystallization latent heat is twice or more. As a result, the heat load on the mold can be reduced, which is effective for the life of the mold, and the manufacturing equipment is simplified and mass production is facilitated.
In addition, by setting the amount of generated gas at the time of melting to 200 ppm or less (melting point + 30 deg.), Corrosion of the mold can be suppressed, which is convenient. Further, from the viewpoint of the strength of the insulator, it is selected from at least one of carbon fiber, glass fiber, silicon carbide fiber, aromatic polyamide fiber, potassium titanate whisker fiber, alumina powder, silica powder, molybdenum sulfide powder, and graphite powder. Those containing 95% by weight or less of the inorganic filler, and those containing 10 to 50% by weight are easy to use. For such a resin, it is preferable to increase the content of the filler from the viewpoint of heat resistance, thermal conductivity, or cost, but there is also a problem that the resin is brittle if added too much. And more preferably about 30-40% by weight. Further, a liquid crystal polyester molded product to which a lubricant of a stearic acid-based metal salt is not added or 3.0% by weight or less is added, and is disposed on a winding frame portion on which a coil is directly wound and on an inner or outer diameter side of a stator. And a terminal box for connecting the windings to the wall, and a side gate is provided near the mold dividing surface of the wall on the inner or outer diameter side. 2 mm □ or less, and the gate is provided in the concave portion. The surface roughness of the winding frame portion of the insulating material on which the winding is wound around the stator teeth portion is set to 10 μmRz or less.
[0023]
The liquid crystal polymer (LCP) as used herein is a polymer that exhibits a liquid crystal structure, and is in an intermediate state between a solid in which molecules are oriented and do not flow when melted and a liquid in which molecules are not oriented and flow in a random state. If the resin exhibits this liquid crystallinity when it is melted, it has good fluidity and the injection molding becomes easy. The liquid crystal polyester resin of the present invention is a wholly aromatic main chain type in which monomers having benzene rings are connected by an ester bond, and heat resistance and strength characteristics are easily obtained by the rigid linear orientation. This resin is mixed with 30 or 40% of an inorganic filler, and a resin having a melting point of 290 ° C. and a generated gas amount of 150 ppm / g or less upon melting is used for molding.
[0024]
FIG. 3 is a diagram showing a comparison of characteristics between a liquid crystal polyester resin and PPS. The liquid crystal polyester resin (LCP) includes six kinds of resins including a change in molding conditions, and a polyphenylene sulfide (hereinafter referred to as PPS) which is a conventional example for reference. Resin). The inorganic filler is the filling amount of the glass fiber. The lubricant is a release material that makes it easier to remove the molding resin from the mold during injection molding. If the resistance is large when the resin molded product is removed from the mold, problems such as deformation of the resin and galling occur. There are those that are included in the resin and those that are sprayed on the mold, but in the case of the present invention, since the shrinkage during solidification is uniform and the rigidity of the resin itself is high, it is easy to release, and it is not necessary to use a release material almost at all. In order to solve the light weight instability of the equipment, an internal mold release agent is used in part, so that the screw shape of any molding equipment can be used.
[0025]
The extraction amount shown in FIG. 3 is an oligomer extraction amount, and a polymer compound generally has a molecular weight of 10,000 or more and has a regular repeating structure, and the number of repetitions, tens to hundreds, is referred to as a polymer. An oligomer having a polymer of up to about 20 is called an oligomer, and is an amount of such a low molecular component eluted into a refrigerant or a refrigerating machine oil. If the amount of the extracted oligomer is large, it precipitates in a low-temperature portion of the refrigerant circuit and causes clogging of the refrigerant circuit. The thermoplastic resin melts when it is overheated, and its melting point is this melting temperature, and this melting point is measured by, for example, a differential scanning calorimeter (DSC). The latent heat of crystallization is the calorific value obtained from the area of the crystal peak when the resin melted by DSC or the like is cooled and cooled at a constant rate. The crystalline resin that solidifies after melting crystallizes at a certain temperature and generates heat. You say this calorific value. If this heat generation amount is large, it takes a long time for cooling and a long time for molding. Also, the thermoplastic resin generates a small amount of gas upon melting. This is caused by unreacted components remaining due to insufficient polymerization in the resin production stage, by-products and impurities due to the reaction of terminal groups, or by the thermal decomposition of a small amount of the resin itself. The amount also increases. When this gas amount is large, slag and the like adhere to the mold more frequently, and corrosion and wear increase. Depending on the amount of gas generated during melting, the mold life is shortened due to corrosion and wear of the mold.
[0026]
Holding pressure is a time for keeping the pressure from injection to cooling. If the pressure is extremely long, the molding cycle becomes long, which is a problem in mass production. The glycerin BDV value is a method of measuring the dielectric strength of the insulation layer of an electric wire. The voltage applied to an electric wire immersed in a glycerin solution is used to measure the breakdown voltage, the breakdown voltage. High reliability, especially where there is a low portion, may cause a layer short based on that portion. In the winding process of the motor, the wire contacts the jig or nozzle during the winding process, and the insulation film is damaged. If the surface roughness of the insulator 5 on which the winding is wound directly is rough, the wire film will deteriorate. There is an impact. Hold pressure during molding. The resin shrinks during solidification, and at this time, shrinkage such as shrinkage and recesses is likely to occur. At this time, the cylinder is rotated and the pressure is continuously applied to the injected resin. That is, the filling amount of the resin is secured by the holding pressure to prevent sink. When the holding pressure is low, the surface roughness increases, and the surface roughness is 10 μm RZ in consideration of insulation reliability. Therefore, it is preferable that the holding pressure is larger than the holding pressure when molding the PPS resin. The mold transferability of transferring the shape of the mold surface to the resin by applying the pressure can be improved, and the surface roughness of the resin after molding increases. FIG. 3 shows the results of verifying the effect of the LCP resin, and shows the reliability evaluation such as the presence or absence of burrs and the voltage breakdown value of the winding and the selection of the molding conditions.
[0027]
As shown in FIG. 3, the test resin has one type of PPS resin and two types of LCP resin for comparison, and the LCP was measured by changing the molding conditions (holding pressure) to three conditions and two conditions, respectively. Verification was performed on six types. Since the LCP resin has a low melt viscosity, biting into the screw groove is poor depending on the specifications of the molding machine screw, and the measurement may not be stable. In order to prevent this, a small amount of a lubricant may be added, but a fatty acid amide-based additive is added to LCP-1c, and a stearic acid-based additive is added to LCP-2 at 0.3 wt%. . The molded product of each resin in FIG. 3 was pulverized, and the amount of oligomer extracted was evaluated by a Soxhlet extraction test using chloroform. LCP-1 has half the extraction amount of the PPS resin, and LCP-2 has the same extraction amount as the LPS-1 due to the addition of the additive, but is still equivalent to the PPS resin. It was found that there was no inconvenience that the extract clogged the refrigeration circuit even when used in the middle compressor, and it was excellent in reliability.
[0028]
Next, the melting points of the respective resins were measured by DSC. Since all the resins had a melting point of about 290 ° C., the heat resistance of a normal injection molding machine was sufficient. The latent heat of crystallization was measured by DSC. This represents the amount of heat generated during the time the crystalline resin is solidified from the molten state.If this value is large, it takes a lot of time to hold and cool the mold, and if this value is small, Since it is easily solidified, the cooling time is very short. From these results, since the LCP resin has a very low latent heat of crystallization of 3 J / g or less, high cycle molding with a short cooling time is possible. Then, the amount of generated gas of each resin at the time of melting was measured. However, the LCP resin has a smaller amount of generated gas than the PPS resin and does not contain corrosive sulfur components. This has the advantage of extending the life of the device.
[0029]
Next, each resin was molded into an insulator shape using the same mold and molding machine, and the surface roughness at the top of the bobbin facing the end face of the tooth was measured. Subsequently, an insulator is inserted into the teeth. For example, the winding is actually wound using a wire diameter of φ1.1, and then the winding is unwound one turn at a time, and the BDV in glycerin is wound. The damage given to the coating of the winding was verified by measuring the values. From these results, under the same pressure-holding condition, the LCP resin is slightly inferior in mold transferability to the PPS resin, the surface roughness of the molded product is low, and the damage to the winding film is proportional to the surface roughness. It was a bad result. However, it was found that the surface roughness was improved and the damage to the wound film could be reduced by increasing the holding pressure. In other words, by using LCP resin for the insulator and setting the surface roughness of the winding frame on which the winding is wound to 10 μm RZ or less, the winding coating is not damaged and insulation reliability can be secured. .
[0030]
FIGS. 4, 5 and 6 show the structure of an insulator 5 which is divided into two parts in the axial direction of the stator teeth and inserted into the teeth from the axial ends of the teeth 3, respectively. FIGS. 4 and 5 show a half of the insulator 5, in which the insulator 5 having almost the same shape as that of FIGS. 4 and 5 is inserted from the opposite axial end and a part of the butted portion is partially overlapped. Insulation between the iron core can be configured by winding the winding into a bale winding. 4 shows a plan view seen from the back yoke 2 side, and a right side view shows a side view thereof. An electric wire is wound between the inner diameter side wall 9a on the rotor side and the outer side wall 9b on the yoke side. The bobbin 8 is shown. 4 is a view on the upper side of FIG. 5, and a view from the rotor side is a view on the lower side. A terminal box 10 is integrally formed at the axial end of the insulator, and has a step 13 provided in the axial direction near the root of the inner wall 9a of the insulator. The size of the gate is 1.2 mm □ or less. That is, the step 13 is provided in the axial direction of the inner wall 9a, and the gate 11 is provided at the mold dividing surface position in the recess of the step 13. According to this configuration, the mold can be formed into a two-plate structure, so that the number of parts can be reduced and the cost can be reduced. Further, since the gate size is 1.2 mm □ or less and provided in the concave portion, the detachability is good, and even if there is a remaining gate, it is a concave portion, so it does not protrude to the outer end surface of the inner wall, It does not come into contact with the rotor that rotates across the small gap at the position facing the inner wall. Although this figure shows an insulator divided for each tooth, the insulator is not divided for each tooth, but is an integral shape that is connected to a plurality of teeth and is connected to a part of an annular or circular arc. Has the same effect.
[0031]
FIG. 6 is a schematic vertical sectional view of the winding frame 8 of the insulator divided into two parts vertically with respect to the axial direction of the annular stator. A side gate 11 is provided at one location near the mold dividing surface in the concave portion of the step provided on the insulator inner diameter wall 9a, and molding is performed using a two-plate mold. The gate 11 is provided on a center line passing through the top of the top reel in FIG. D in FIG. 6 shows the width in the direction perpendicular to the teeth at the portion in contact with the stator teeth end face at the base of the winding frame, d shows the width in the direction perpendicular to the teeth at the tip of the winding frame, and Assuming that the D dimension of the mold is the same as that of the PPS resin, the molding shrinkage of the LCP resin is small (the value of d / D is larger than that of the PPS resin). The stress applied at the time of insertion into No. 3 became low, and cracks did not occur at the root of the winding frame portion. Further, the thickness of the winding frame 8 can be reduced as compared with the PPS resin. Further, since the stress does not increase even if the root width of the winding frame is smaller than that of the PPS resin, the clearance with the stator teeth 3 can be reduced. That is, the amount of deflection of the insulator 5 due to the winding tension and the vibration of the winding machine during the winding process is reduced, and the alignment of the windings is improved, that is, the occupying ratio is improved, so that the motor efficiency is improved. The result was obtained.
[0032]
FIG. 7 illustrates a method of manufacturing a stator core of a concentrated winding motor. First, two types of core pieces 20a and 20b as shown in FIG. 7A are formed by deflecting, that is, punching. For example, two types of core pieces 20a and 20b are formed by stamping out a magnetic material. Each of the core pieces 20a and 20b has a connecting portion 22 having a convex portion on the front surface and a concave portion on the rear surface.
[0033]
Next, as shown in FIG. 7B, two types of core pieces 20a and 20b are laminated. Lamination is performed as follows. First, the core member 21a is formed by arranging the same type of core pieces 20a in a plurality of linear shapes (band shapes). Next, a layer is formed by arranging other types of core pieces 20b in a band shape on the core member 21a. At this time, lamination is performed so that the concave portion on the back surface of the core piece 20b is fitted to the convex portion on the front surface of the core piece 20a. That is, the protrusions and recesses of the core pieces adjacent to each other in the stacking direction are fitted. Further, the core pieces 20a are arranged in a band shape on the core member 21b composed of the core pieces 20b. Also at this time, lamination is performed so that the concave portion on the back surface of the core piece 20a is fitted to the convex portion on the front surface of the core piece 20b. In this way, the core member 21a composed of the core piece 20a and the core member 21b composed of the core piece 20b are alternately laminated to form the stator core 12.
[0034]
The stator core 12 formed as described above is rotatable around the connecting portions 22 of the convex and concave portions provided on the core pieces 20a and 20b, respectively. Then, the insulator 5 as an insulating member is attached to the teeth of the stator core 12. This insulator is formed of LCP resin. After the insulator 5 is attached, as shown in FIG. 7 (c), the stator core 12 is straightened (the back yoke is in a horizontal state), or the back yoke is set to 180 ° or more so that the tooth tip is opened. While maintaining the developed state, the winding 4 is applied around the teeth 3 via the insulator 5. Thereafter, the connecting portion 22 is formed into an annular shape by rotating. Thus, the stator shown in FIG. 1 is finally manufactured.
[0035]
By adopting this motor manufacturing method, it is possible to provide a concentrated winding type motor having good winding properties and higher efficiency. In this method, the procedure of forming the core pieces 20a and 20b and then stacking them is described. However, the core pieces 20a are formed and stacked, and then the core pieces 20b are formed and stacked. The stator core may be formed by repeatedly forming and laminating the core pieces. In a manufacturing method in which an insulator is divided into upper and lower parts of the stator core in advance and inserted as separate pieces for each tooth, the thickness 14 of the winding frame portion is set at 0.1 mm. If 5 mm is the limit and is thinner, cracks occur at the root of the bobbin due to stress during insertion and winding. Conversely, if the thickness is 1.5 mm or more, the area of the stator slot 16 is reduced, so that the efficiency of the motor is reduced. That is, when the thickness of the bobbin is in the range of 0.5 mm to 1.5 mm, an electric motor excellent in productivity and efficiency can be provided.
[0036]
Next, a case where the stator core is inserted into a mold and an insulator is integrally formed so as to cover the stator teeth will be described. According to this method, the clearance between the stator teeth and the insulator is substantially zero as compared with the method in which the insulator divided in advance and vertically is inserted as a separate piece for each tooth.
Furthermore, since there is no disturbance in the winding property due to backlash, the space factor is improved. Furthermore, productivity is excellent because there is no insertion step of inserting the teeth into the teeth for each insulator, and there is no crack at the root of the bobbin due to the stress at the time of insertion. Because it is good, the space factor can be improved. If the thickness of the winding frame is 0.2 mm, the insulation properties can be satisfied. Conversely, since the area of the stator slot 16 having a thickness exceeding 1.5 mm is reduced, the efficiency of the motor is reduced. That is, when the thickness of the winding frame is in the range of 0.2 mm to 1.5 mm, an electric motor excellent in productivity and efficiency can be provided. In this manner, the insulating molded body 5 integrally formed with the stator does not receive any extra stress during winding, that is, since there is no element such as a gap between the insulation and the iron core, which increases the stress, there is no stress. There is no problem if the thickness is more than millimeters, and the shape of the winding frame can be integrated into the shape of the iron core, making it easier to manufacture thinner shapes. It is sufficient that the thickness is smaller than 1.5 mm, and if the thickness is at most 0.9 mm, there is no problem in the winding operation.
[0037]
FIG. 8 is an explanatory diagram of a winding method of the core 12 that has a back yoke portion 2, a plurality of teeth portions 3, and a connecting portion 22 connecting the plurality of teeth portions of the stator, and is bendable at the connecting portion 22. FIG. 8a shows a wedge 15 for inserting the stator into a mold to insulate the back yoke 2 from the windings 4 in a thin shape in a direction parallel to the tooth tips of the teeth 3. FIG. 8B shows a process of integrally molding. FIG. 8B shows a process in which the connecting portion 22 is moved to open the tip side of each of the teeth 3 and the back yoke is expanded to 180 ° or more, and then the resin is heated and then a machine such as a jig is formed. FIG. 8c shows a process in which the wedge 15 is deformed in the direction perpendicular to the teeth by using a means or the like, and then the winding is performed directly on the teeth 3. FIG. Shows a step of returning the tooth 3 to the right angle direction again, The unfolded tooth 3 moves the connecting portion 22 to finally form an annular shape as shown in FIG. According to this method, the insulation between the stator back yoke portion 2 and the winding 4 can be ensured without inserting insulating paper, sheet-like insulating resin, or the like as inter-teeth insulation, thereby reducing the number of parts. it can.
[0038]
FIG. 9 is an explanatory diagram illustrating a process of inserting the insulator 5 into the stator core 12. As shown in FIG. 8A, the coil is inserted into the core without any winding, so that it can be performed with a simple operation. In the electric motor manufactured by the above manufacturing method, it is effective to increase the number of slots and the number of poles of the electric motor in order to reduce vibration and noise of the electric motor. The conventional concentrated winding motor has a low winding space factor, so there is a limit to increasing the number of poles.However, the concentrated winding motor of the present invention can increase the space factor of the stator slot, Even if the number and the number of poles are increased, the efficiency does not decrease, so that the number of poles can be increased to four or more, more preferably six, and a small-sized one with good performance can be obtained.
[0039]
FIG. 10 is an explanatory view for explaining a state in which the insulator 5 is molded in the mold device of the injection molding device 50. The mold device includes a fixed mold 37 and a movable mold 36. A mold for determining the shape of the molded product 5 from the gate 11 through a sprue 34 and a runner 35 which are resin flow paths in the mold, and the molten product of the resin described above injected from an injection molding apparatus (not shown). To the interior space. The mold division surface, which is the boundary between the fixed mold and the movable mold, is the surface where the gate 11 connected to the runner exists. As a result, a two-plate mold can be used, so that a manufacturing apparatus with a small number of parts can be obtained. Moreover, the molding cycle time is shorter than that of a three-plate mold machine, which is effective for mass production. Of course, if a mold having many plates such as a three-plate mold is used, the gate position can be freely selected, for example, by providing a more complicated shape or providing a gate at the end of the wall.
[0040]
FIG. 11 is an explanatory diagram illustrating the entire injection molding apparatus. In the injection molding machine, the resin is melted in a cylinder 39 supplied from a hopper 38 into which a fixed amount of resin pellets or granules are charged and extruded by a screw 40 toward a mold apparatus. The molten resin pushed into the fixed mold 37 from the injection molding machine is injected into the space of the molded product 60 from a flow path such as a sprue 34. The movable mold 36 is driven in the direction of the fixed mold 37 with respect to the fixed platen 42 to integrate the mold apparatus. After the mold is clamped, the resin is injected and injected. After the resin is injected, the pressure is maintained, and after cooling and solidification, the movable mold 36 is broken off at the gate with the molded product fixed in the direction of the fixed platen 42 and peeled off. The post-injection molding machine is also separated from the fixed mold 37 by the movable platen 41. The molded product can be removed by being pushed out of the movable mold by a pin.
[0041]
As described above, one cycle of the injection molding is composed of the steps of measurement, mold clamping, injection, holding pressure, cooling, mold release, and product removal. If the weighing time is not included in the injection molding cycle since the weighing of the second cycle is started during the cooling process of the first cycle, the time from mold clamping to product removal is one cycle time. Since the closing and the removal time depend on the molding machine capacity and the mold structure, the injection, holding pressure and cooling time depend on the resin characteristics. As described above, by using the LCP resin of the present invention, the cycle time can be shortened, and a large-scale molding machine can be easily manufactured without using a large-scale molding apparatus for cooling or the like.
[0042]
As described above, the insulator 5 manufactured by the device shown in FIG. 10 is divided in the teeth axis direction, and prevents the winding frame 8 around which the winding is wound and the winding wire 4 from leaking in the direction perpendicular to the teeth. For this reason, it is constituted by inner diameter walls or outer walls 9a and 9b provided at positions facing the coil ends in the axial extension direction, and a terminal box 10 for connecting windings is provided on the outer wall. As shown in FIG. 5, a step 13 of about 1-2 mm is provided on the inner diameter wall portion, and a gate having an area smaller than 1.2 mm square is provided in the recessed portion, and molded by a thermoplastic liquid crystal polyester resin. It is. In molding, a mold dividing surface is provided near the gate 11 on the same surface as the surface on the back side of the top of the winding frame, where the winding frame portion 8 of the insulator 5 is in contact with the end surface of the stator teeth as shown in FIG. On the fixed mold 37 side, a cavity and a runner and a gate having the shape of the inner and outer diameter walls of the insulator 5, the top of the bobbin are formed, and on the movable mold 36 side, a cavity below the top of the bobbin. Let it form. As a result, a resin molded product can be manufactured with a two-plate mold that can smoothly inject the resin and can easily mold and release the product. In the case of a mold apparatus, since a large injection pressure acts on the mold, mold clamping is performed by hydraulic pressure or air pressure to withstand this force.
[0043]
After the cavity is filled with the resin, the insulator 5 is formed by cooling and solidification. Next, the mold is opened and the eject pin embedded in the movable mold is projected to take out the mold from the product and the runner. At this time, the eject pin is provided on both the surface on the back side of the top of the bobbin on the product side and the runner part, the undercut part is provided on the runner side pin, and only the runner side is held, and the mold release from the molded product is performed. That is, by separating the product from the movable mold slightly earlier than the runner by shifting the timing of projecting the pins, the step of separating the runner 35 at the gate position without applying much force to the gate can be omitted. This not only eliminates the need for a gate separation step, but also makes it possible to keep the gate residue after the gate separation short. This gate residue does not protrude from the recess of the step, and the gate processing is also unnecessary, thus simplifying the process. It is possible to make the production system excellent in productivity.
[0044]
As described above, the insulating member provided between the yoke and the teeth, which is a coil wound directly on the iron core forming the stator and energized and provided with insulation, contains a fibrous inorganic reinforcing material or an inorganic filler. Injecting the liquid crystal polyester resin of the present invention into a mold to form a resin molded product, the liquid crystal polyester resin has a melting point of 350 ° C. or less, and a generated gas amount upon melting is 200 ppm or less, Since a thermoplastic resin having a crystallization latent heat of 10 J / g or less is injected into the mold and subjected to thermoplastic injection molding, a simple and fast electric motor manufacturing method from injection to removal of a molded product can be obtained. Further, the liquid crystal polyester resin is supplied from a gate provided at a tip of a wall portion on the inner diameter side or the outer diameter side or a concave portion of the molded product at the base of the wall at a portion facing the coil end which is an axial end of the coil of the resin molded product. Since implantation is performed, a gate processing step and the like can be omitted. In the above description, the recess is provided on the inner diameter side wall surface and the gate is individually brought. However, a concave portion such as a terminal box on the outer diameter side wall surface may be used, and further, the rotor is provided inside the stator. However, it is obvious that a similar shape and a similar manufacturing method can be applied to an outer rotor, that is, a structure in which the stator is provided on the center side and the rotor is disposed on the outer side.
[0045]
FIGS. 12 and 13 are explanatory views illustrating the configuration of another molding apparatus for producing a molded product by injection molding using the liquid crystal polyester resin of the present invention. That is, a core having a plurality of teeth 3 projecting in the inner or outer direction of a yoke 2 forming the stator 1, a winding 4 which is a coil wound directly on the teeth 3 and energized, and a coil. When manufacturing an electric motor provided with an insulator 5 provided between the teeth portion 4 and the teeth portion 3 to perform insulation, a liquid crystal polyester resin containing a fibrous inorganic reinforcing material or an inorganic filler is used as the insulating member 5. When molding the resin molded product by injecting the resin into the mold, the stator 1 is directly embedded in the mold, and particularly, the teeth are inserted into the cavity so that the resin is directly adhered to the teeth portion 3 and integrated. A liquid crystal polyester resin is injected, and the stator and the resin molded product are integrally formed.
[0046]
In this manufacturing method, the wedge 15 for insulating the yoke 2 and the coil 4 of the stator 1 described above with reference to FIG. 8 is thinned in a direction parallel to the tooth tips of the teeth 3 of the stator 1. Injection molding can be performed integrally in a mold. As described above, a fibrous inorganic reinforcing material or an inorganic filler is contained so as to form an insulating member provided between the coil and the iron core, which is directly wound around the iron core teeth forming the stator of the electric motor and energized, and provides insulation. In the case of a mold for molding a resin molded product by injecting a liquid crystal polyester resin to be formed, a cavity is provided around the teeth portion 3 while covering the iron core portion of the stator, and the cavity is covered.
[0047]
FIG. 12 is a front view of the mold, and FIG. 13 is a side view of the mold. The nozzle 51 of the injection molding machine is configured to inject the resin when it comes into contact with the fixed platen 42 and to separate when finished. The sprue is a flow path of the molten resin provided from the fixed platen 42 to the runner stripper 52 and the fixed mold 37. The resin is injected from the gate 11 into the cavity via the runner 35. At the time of molding, the movable mold 36, which is clamped to the fixed mold 37 and integrally forms a cavity, includes a fixed mold together with an injection pin, which is not described, in which the slide mold 36A and the slide mold 36B are also received on the movable platen 41. The mold is closed, the mold is opened, and the molded product is taken out.
[0048]
In the manufacturing method using the insulator-integrated molding die, first, as shown in FIG. 8, first, the back yoke 2 is brought into a horizontal state by freely operating by a connecting portion 22 that connects each tooth portion. In the state where the mold apparatus of FIG. 12 is opened, the stator core 1 is fixed to a predetermined position of the slide mold 36B with the back yoke on the movable platen 41 on the lower side in the figure. At least one pair of the slide dies B is provided, for example, one is fixed, and the other is slid in the lateral direction to press the yoke to one of the set positions and to suppress the yoke from both sides. Next, a slide mold 36A that covers both end surfaces in the axial direction of the stator core 1 through the space of the insulating material 5 is also slid from both sides in the axial direction, inserted into the stator slot portion, and joined at the center portion of the stator slot. Then, the movable platen 41 and the movable dies of the slide dies 36A and 36B are driven by hydraulic pressure or air pressure to be fixed to the fixed die, and the runner stripper plate 52 and the fixed plate are clamped together to reduce the pressure in each direction. Hold at a pressure higher than the resin pressure during molding. In this way, the stator core, the slide dies 36A and 36B, and the fixed die form a cavity, which is a space into which resin is injected in an insulator shape.
[0049]
Subsequently, the liquid crystal polyester resin is injected by bringing the cylinder nozzle of the injection molding machine into contact with the spool bush, which is the molten resin inlet of the fixed board. The molten resin that has passed through the sprue 34, the runner 35, and the gate 11 flows into the cavity and performs cooling such as passing water through piping in a mold, solidifies the resin, and integrally forms the insulator 5 with the stator core. Let it. A resin having good fluidity is used as in the present invention. In addition, for example, one gate is provided on the inner wall portion of the insulator for each tooth, the resin flow length is set to half of the core lamination thickness, and the resin is injected. This prevents solidification during flow and short-circuit failure. As shown in the figure, by providing a cavity of the wedge 15 between the slide molds 36A and 36B and between the fixed mold and the slide mold, the wedge 15 can be formed together with the insulator 5 at the time of molding, for example, in any shape. It can be molded even if it is made thin. In the description of FIG. 8, the structure in which the wedge position is provided only on the outer diameter wall side has been described. However, the wedge position can be easily provided on the inner diameter wall side.
[0050]
In this manner, the stator has a back yoke portion, a plurality of teeth portions, and a connecting portion connecting the plurality of teeth portions. The connecting portion has a bendable stator core, and the stator core is inserted into a mold device. And molded integrally with the insulating resin, the thickness of the molded insulating material on the surface on which the winding is wound in the axial direction of the stator teeth can be 0.3 to 0.9 mm, An even more efficient and reliable electric motor can be manufactured.
[0051]
In the manufacture of the structure having the wedge 15, a wedge for insulating the back yoke from the winding is first injection-molded in a mold in a thin shape in a direction parallel to the tooth tip of the teeth. After the process and the connecting portion are moved to open the tip end side of each tooth and spread out in the horizontal direction or more, the material is heated to a temperature higher than the thermal deformation temperature of the resin, or the wedge is toothed using a mechanical means such as a jig. A step of directly deforming the teeth after applying a deformation in the perpendicular direction, and returning the wedge deformed after the winding back to the perpendicular direction of the teeth again by the same method as described above; Can be manufactured by the operation of the step of moving the ring to form a ring.
[0052]
In the above description, the expandable stator having the connecting portion 22 is extended in the horizontal direction and then injection-molded. However, it is also possible to insert an annular stator into a mold and mold it integrally with the insulating resin. As a result, the stator teeth are covered, and the insulation molding on the surface on which the winding is wound in the axial direction of the teeth can be made as thin as 0.3 to 0.9 mm. In the work of winding the wire in the horizontal deployment state, the thickness of the insulation can be determined only by the dielectric strength and can be made as thin as 0.2 mm or more because of the simple work without applying excessive force. Winding requires a thickness of 0.3 mm or more in consideration of the load on insulation such as the direction of force being changed due to the complicated operation of the winding machine.
[0053]
A description of another mold apparatus is shown in FIGS. FIG. 16 shows a state in which the molten resin injected from the molding machine nozzle of the insulator 5 is solidified in the cavity of the mold apparatus being clamped. The injected molten metal passes through a path 71 for transporting the molten plastic, and from a runner 35 through a gate 11, a square hole or a round hole is dug into a mold plate of a die body into a core nest 74, 75 in which a hole is dug into a hole. Is filled and solidified to form the insulator 5. At this time, the intermediate passage is also filled with the molten metal like the sprue 34 and the runner 35 and solidified. In this state, the lock push pin 82 embedded in the lower part 79 of the ejector plate has a clearance d below the head. When the upper and lower ejector plates 78 and 79 are raised by the ejector rod 81 which is a shaft for transmitting the power of the molding machine, the pushing pin 82 does not operate to the distance of the clearance d. Therefore, the runner lock pin 76 starts to move more slowly than the ejector pin 77 pushed by the ejector plates 78 and 79, and the operation timing is delayed. That is, the runner lock pin 76 operates with a time difference from the ejector pin 77. At the time of opening the mold, the runner is pulled to the movable side to pull out the spool from the spool bush, and to push out the runner lock pin 76, which serves to separate the runner from the runner at the gate 11, and to take out the runner 35 from the mold. The upper portion of the pin 82 is shaped to fit into the undercut portion of the runner 35 as described in detail in FIG. 16B. The undercut does not have to be provided as long as it can bite into the runner and be held firmly on the movable side. The ejector plates 78, 79 can move within a spacer block 80 which creates space for the extruder to move.
[0054]
FIG. 17 is a view for explaining the step of opening the mold from FIG. 16, and shows the mold opening in which the movable mold is opened downward by the power of the molding machine. The insulator 5, the runner 35, the sprue 34, etc., which are resin molded products in which the molten metal is solidified by separating the movable side and the fixed side of the mold, remain in a state of being adhered to the movable side mold, and are released from the fixed side. You.
[0055]
FIG. 18 is a view for explaining the operation of releasing the molded product from the movable mold. The ejector rod 81 driven by hydraulic pressure or the like performs the product ejection operation for releasing the molded product. The ejector rod 81 moves the ejector plates 78 and 79 to the fixed side, and the ejector pins 77 first push the molded product 5 from the mold by the clearance d. At this time, since the runner 35 is held by the runner lock pin 76, the product 5 and the runner 35 are automatically cut at the gate position. As described above, since the gate has a size of 1.2 mm square or less, the molded product and the runner can be easily cut only by extrusion with a pin. Conversely, the dimension d may be larger than the dimension at which this cutting can be performed. FIG. 19 is an explanatory view of taking out the product, the runner and the like. When the ejector plates 78 and 79 are further raised, the runner cut at the gate position is pushed out of the mold by the lock pin, so that it can be easily taken out. In this way, the molding cycle can be simplified by giving a time difference in mold release between the injection molded product and a runner or the like which is a solidified product such as a path in a mold. Naturally, the product is also pushed out of the mold, and when the robot arm reaches a position where it can be chucked and taken out, the product and the runner with the sprue can be taken out at the same time. With such a configuration, a simple and short injection molding cycle can be performed.
[0056]
A comparison of the molding cycle of the PPS resin and the LCP resin will be described with reference to FIG. As described above, the molding cycle involves the steps of mold clamping, injection, holding pressure, cooling, mold release, and product removal. In the liquid crystal polyester resin of the present invention, the latent heat of crystallization is significantly smaller. It can be seen that since the crystallized resin has a small amount of heat until it solidifies during cooling, it generates less heat and the cooling time is greatly reduced. Even if the other processes are not significantly different, the mold can be cooled quickly and the molding cycle can be greatly shortened, so that the product can be obtained in a short time and mass production can be easily performed. As described above, according to the present invention, an electric motor with high efficiency, high reliability, and mass production can be obtained. Further, it is possible to obtain a method of manufacturing a motor having a short manufacturing cycle and suitable for mass production. Further, it is a mold device for this electric motor having a simple structure and a long life.
[0057]
FIG. 15 shows a refrigerant circuit diagram when the electric motor of the present invention is used for a compressor in a refrigeration cycle. The figure shows a refrigeration circuit composed of a compressor 30, an evaporator 31, a condenser 32, and a throttle 33. The compressor 30 has a built-in electric motor for driving the compressor high part inside a closed container, The motor is equipped with the concentrated winding motor of the present invention. In this refrigerant circuit, the refrigerant is compressed by a compressor to be a high-temperature and high-pressure gas refrigerant. After the temperature of the refrigerant is reduced and liquefied in a condenser 32, the pressure is reduced in a throttle 33, and the refrigerant is evaporated in an evaporator to almost a gas state. Then, the refrigerant is returned to the compressor again, but the built-in electric motor is in a state where such refrigerant or lubricating oil for rotating the compression mechanism or the like is always immersed. A refrigerant and a refrigerating machine oil are included in this circuit, and difluoromethane, 1,1,1,2,2-pentafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoromethane are used as refrigerants. At least one of fluoroethane, chlorodifluoromethane, carbon dioxide, ammonia, dimethyl ether, propane, and butane, and as a refrigerating machine oil, ester, ether, glycol, alkylbenzene, polyalphaolefin, Even when used in combination with at least one of polyvinyl ether-based, naphthenic-based mineral oil, and paraffin-based mineral oil, the insulation of the motor is affected by these refrigerants and lubricating oil at the temperature and pressure during operation. In addition, the electric motor of the present invention does not cause circuit blockage due to sludge generation and the like, and has excellent long-term reliability without refrigerating air conditioners. Get it can be. Further, even when a sintered permanent magnet, a plastic ferrite permanent magnet, or a rare earth permanent magnet is used for the rotor of the electric motor of the present invention, there is no influence of the refrigerant or the refrigerator, and the efficiency of the electric motor becomes higher, and the insulation performance is improved. And a highly reliable electric motor and refrigeration / air-conditioning system can be obtained.
[0058]
As described above, the electric motor according to the present invention includes an annular back yoke formed of laminated steel sheets, an iron core having a plurality of teeth protruding in the inner or outer peripheral direction of the back yoke, the teeth and the teeth directly. In a concentrated winding type motor having a stator composed of a coil to be wound and an insulating member (insulator) for insulating the coil from the teeth, the insulating material has a melting point measured by DSC of 350 ° C. In the following, the latent heat of crystallization is 10 J / g or less, the amount of generated gas at the time of melting is 200 ppm or less (melting point + 30 deg), carbon fiber, glass fiber, silicon carbide fiber, aromatic polyamide fiber, potassium titanate whisker fiber, alumina 95% of at least one selected from a fibrous inorganic reinforcing material such as whisker fiber or an inorganic filler such as silica powder, molybdenum sulfide powder, graphite powder, etc. It is a liquid crystal polyester molded product containing no more than 3.0% by weight of a lubricant of stearic acid type or fatty acid amide type, containing no more than 3.0% by weight, and is highly reliable and easy to manufacture.
[0059]
According to the present invention, the insulating material includes a winding frame on which the coil is directly wound, a wall disposed on the inner or outer diameter side of the stator, and terminals on the wall for connecting the windings. A box is provided, a side gate is provided on either the inner or outer wall, and the gate size is 1.2 mm □ or less.
[0060]
Further, since the surface roughness of the winding frame portion of the insulating material on which the stator teeth are covered and the winding is wound is set to 10 μmRz or less, insulation reliability is high.
[0061]
Also, an insulating material molded product divided into two parts vertically with respect to the axial direction of the annular stator is inserted, and the thickness of the molded product on the surface on which the winding is wound in the axial direction of the stator teeth portion is set to 0. 5 to 1.5 mm, a step is provided on the inner or outer diameter side wall, a side gate is provided at one place near the mold division surface in the concave portion of the step, and molding is performed using a two-plate mold. Therefore, the manufacturing apparatus is simple and inexpensive.
[0062]
Further, the stator has a back yoke portion, a plurality of teeth portions, and a connecting portion connecting the plurality of teeth portions, and a stator core that can be bent at the connecting portion, and a pair of upper and lower splits is provided for each tooth portion. Insert the molded insulation material, cover the stator teeth, and adjust the thickness of the insulation molded product on the surface where the winding is wound in the axial direction of the teeth to 0.5 to 1.5 mm. A step is provided on the inner or outer wall, and a gate is provided at one place on the mold dividing surface in the concave portion of the step, and the two-plate mold is used to form an efficient motor. Can be produced with high productivity.
[0063]
In addition, an annular stator is inserted and molded integrally with the insulating resin to cover the stator teeth, and the thickness of the insulating material molded product on the surface on which the winding is wound in the axial direction of the teeth. Is set to 0.3 to 0.9 mm, a highly efficient electric motor can be obtained.
[0064]
Further, the stator has a back yoke portion, a plurality of teeth portions, a connecting portion that connects between the plurality of teeth portions, a stator core that can be bent at the connecting portion, inserts the stator core, and inserts an insulating resin. It is formed integrally, and the thickness of the molded insulating material on the surface on which the winding is wound in the axial direction of the stator teeth can be made 0.2 to 0.9 mm, so that the efficiency can be further improved.
[0065]
A first step of integrally molding a wedge for insulating the back yoke and the winding into a thin wall in a direction parallel to the tooth tip of the teeth in a mold; After opening the tip side of each tooth and expanding it in the horizontal direction or more, overheat to the heat deformation temperature of the resin or use a mechanical means such as a jig to deform the wedge in the direction perpendicular to the tooth. A second step of directly winding the teeth, and the wedge deformed after the winding is returned in the direction perpendicular to the teeth again by the same method as described above, and the developed teeth are annularly moved by moving the indirect portion. By the third step, a more reliable insulation performance can be easily obtained.
[0066]
【The invention's effect】
According to the present invention, an electric motor having high efficiency and excellent in both productivity and reliability can be obtained. In addition, a highly reliable refrigeration / air-conditioning device can be obtained. In addition, a method for manufacturing a motor that can be easily mass-produced and has high productivity can be obtained. In addition, a motor mold device having high reliability and easy maintenance can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view of an electric motor according to an embodiment of the present invention.
FIG. 2 is an explanatory view in which a slot portion of FIG. 1 of the present invention is enlarged.
FIG. 3 is a diagram showing a comparison of characteristics between a liquid crystal polyester resin as a resin and PPS as a conventional resin in a mobile phone according to an embodiment of the present invention.
FIG. 4 is a front view and a side view of an insulator according to the embodiment of the present invention.
FIG. 5 is a diagram showing a gate position of an insulator and a terminal box according to the embodiment of the present invention.
FIG. 6 is a schematic vertical sectional view of a bobbin of an insulator of the electric motor according to the embodiment of the present invention.
FIG. 7 is a diagram showing a method for manufacturing a stator according to the embodiment of the present invention.
FIG. 8 is a diagram showing a method for manufacturing a stator according to the embodiment of the present invention.
FIG. 9 is a diagram showing a method of manufacturing a stator according to the embodiment of the present invention.
FIG. 10 is a diagram showing a method and an apparatus for manufacturing a stator according to the embodiment of the present invention.
FIG. 11 is an explanatory diagram illustrating an injection molding device according to an embodiment of the present invention.
FIG. 12 illustrates a manufacturing apparatus according to an embodiment of the present invention.
FIG. 13 illustrates a manufacturing apparatus according to an embodiment of the present invention.
FIG. 14 is a comparison diagram of a molding cycle in the embodiment of the present invention.
FIG. 15 is an explanatory diagram of a refrigerant circuit of the refrigerating air conditioner according to the embodiment of the present invention.
FIG. 16 is an explanatory view of a mold according to the embodiment of the present invention.
FIG. 17 is an explanatory view of a mold according to the embodiment of the present invention.
FIG. 18 is an explanatory view of a mold according to the embodiment of the present invention.
FIG. 19 is an explanatory view of a mold according to the embodiment of the present invention.
[Explanation of symbols]
1 stator, 2 stator back yoke, 3 teeth, 4 windings, 5 insulators, 6 rotors, 7 permanent magnets, 8 winding frames, 9 walls, 10 terminal boxes, 11 gates, Reference Signs List 12 stator core, 13 wall step, 14 reel thickness, 15 wedge, 16 slot, 20a, 20b core piece, 21 core member, 22 connecting part, 30 compressor, 31 evaporator, 32 condenser, 33 diaphragm Part, 34 sprue, 35 runner, 36 movable mold, 37 fixed mold, 38 hopper, 39 cylinder, 40 screw, 41 movable board, 42 fixed board, 50 mold apparatus, 51 nozzle, 52 runner stripper, 71 molten plastic , 74 cavity side nesting, 75 core nesting, 76 runner lock pin, 77 ejector pin, 80 spacer block Click, 81 ejector rod,'s a 82 lock push pin.

Claims

An iron core formed by stacking steel plates having a plurality of teeth protruding in the inner or outer circumference direction of a yoke forming a stator; a coil wound directly on the teeth and energized; and a coil between the coils and the teeth. An insulating member provided for insulation, a connecting portion provided on the iron core, which is connectable by bending the iron core in a circular shape while enabling the laminated iron core to be developed, and forming the insulating member. A liquid crystal polyester resin having a melting point of 350 ° C. or less, a generated gas amount at the time of melting of 200 ppm or less, and containing a fibrous inorganic reinforcing material or an inorganic filler, and insulating the core and the coil from each other. An electric motor, comprising: a molded resin product;

An iron core having a plurality of teeth protruding in the inner or outer circumference direction of a yoke forming a stator; a coil directly wound around the teeth to be energized; and an insulation provided between the coils and the teeth. An insulating member to be formed, and a resin molded product which is formed by molding a liquid crystal polyester resin containing 10 to 50% by weight of a fibrous inorganic reinforcing material or an inorganic filler forming the insulating member to insulate the teeth from the coil. Wherein the thickness of the insulating member on the surface of the teeth portion on which the coil is wound in the axial direction is 0.3 to 1.5 mm.

3. The electric motor according to claim 1, wherein a surface roughness of the insulating member that covers the teeth portion and around which the coil is wound in the axial direction is 10 μmRz or less. 4.

The resin molded product is formed integrally with the stator, and covers the teeth portion with the thickness of the insulating member on the surface of the teeth portion on which the coil is axially wound being 0.2 to 0.9 mm. The electric motor according to claim 1, 2 or 3, wherein:

The electric motor according to at least one of claims 1 to 4, wherein a tip portion of the resin molded product on the side of the adjacent teeth is bendable between the yoke and the coil of the resin molded product.

The electric motor according to any one of claims 1 to 5, wherein a sintered permanent magnet, a plastic ferrite permanent magnet, or a rare earth permanent magnet is used for the rotor.

A compressor equipped with the electric motor according to claim 1, comprising a condenser, a throttle mechanism, and an evaporator, wherein the refrigerant is difluoromethane, 1,1,1,2,2-pentafluoro. At least one of ethane, 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane, chlorodifluoromethane, carbon dioxide, ammonia, dimethyl ether, propane, and butane; Is at least one selected from the group consisting of ester, ether, glycol, alkylbenzene, polyalphaolefin, polyvinyl ether, naphthenic mineral oil, and paraffinic mineral oil. apparatus.

A coil wound directly around an iron core forming a stator and an energized coil and an insulating member provided between the iron cores for insulation are injected into a mold of a liquid crystal polyester resin containing a fibrous inorganic reinforcing material or an inorganic filler. When the liquid crystal polyester resin is manufactured by molding to obtain a resin molded product, a liquid crystal polyester resin having a melting point of 350 ° C. or less, a generated gas amount at the time of melting of 200 ppm or less, and a latent heat of crystallization of 10 J / g or less is used. A method for producing an electric motor, comprising: thermoplastic injection molding.

The liquid crystal polyester is taken from a gate provided at a tip of a wall portion on the inner diameter side or outer diameter side or a concave portion of the molded product at the base of the wall, which is a portion facing a coil end which is an axial end of the coil of the resin molded product. The method for manufacturing a motor according to claim 8, wherein a resin is injected.

An iron core having a plurality of teeth protruding in the inner or outer circumference direction of a yoke forming a stator; a coil directly wound around the teeth to be energized; and an insulation provided between the coils and the teeth. Insulating member to be performed, and in the electric motor, when forming a resin molded product by injecting a liquid crystal polyester resin containing a fibrous inorganic reinforcing material or an inorganic filler into a mold so as to form the insulating member, A method for manufacturing a motor, comprising: inserting a teeth portion in a state where the stator is expanded in the mold, injecting the liquid crystal polyester resin, and integrally molding the stator and the resin molded product. .

A wedge for insulating the yoke of the stator from the coil is integrally injection-molded in a mold in a thin shape in a direction parallel to the tooth tips of the teeth of the stator, and each tooth is formed. The wedge is deformed in a direction perpendicular to the teeth to directly wind the teeth after the connecting portions to be connected are moved and the ends of the teeth are opened and opened. Item 11. The method for manufacturing an electric motor according to at least one of Items 8 to 10.

A liquid crystal containing a fibrous inorganic reinforcing material or an inorganic filler so as to form an insulating member provided between the coil and the coil to be energized and energized directly around the iron core teeth forming the stator of the electric motor for insulation. A mold for molding a resin molded product by injecting a polyester resin, and after inserting the teeth portion into the mold with the stator expanded, the liquid crystal polyester resin is injected to form the stator. A mold device for an electric motor, wherein said resin molded product is integrally formed and covers a periphery of said teeth portion.

A liquid crystal containing a fibrous inorganic reinforcing material or an inorganic filler so as to form an insulating member provided between the core and the coil to be energized and energized, which is directly wound around the iron teeth forming the stator of the electric motor, for insulation. A mold for injecting a polyester resin to form a resin molded article, and releasing the resin molded article when injecting the liquid crystal polyester resin and molding and releasing the resin molded article in the mold. A mold release means for providing a time difference in the release of the runner portion.