【０００１】
【発明の属する技術分野】
本発明は、両端に位置する荷重付加部と、この荷重付加部を連結する杆部とが、一体に形成された鋳造製連結部材に関する。
【０００２】
【従来の技術】
図８は、従来の鋳造製連結部材（以下、単に「連結部材」と略す）２１を示し、（ａ）は平面図、（ｂ）は側面図、（ｃ）は鋳造時の（ｂ）の断面Ｅ−Ｅでの溶湯の流れを示す模式図である。また、図９は、従来の別の例の連結部材３１を示し、（ａ）は平面図、（ｂ）は（ａ）での断面Ａ−Ａを示す図である。また、図１０は、従来のさらに別の例の連結部材４１の斜視図である。図８（ａ）、（ｂ）で、連結部材２１は、両端に位置する環状の荷重付加部２２、２３と、この荷重付加部２２、２３を連結する横断面がＩ字型の杆部２８とが、鋳造で一体に形成されている。この連結部材２１は、荷重付加部２２、２３に引張り、圧縮、曲げなどの繰り返しの荷重が付加される。
【０００３】
一体構造の連結部材として、図９（ａ）（ｂ）に示すように、両端に位置する環状の荷重付加部３２、３３と、この荷重付加部３２、３３を連結する杆部３８とが一体に形成された連結部材３１において、杆部３８に曲げ応力抑制部３９なるものを形成し、軽量化を図ると共に耐久性を向上するものがある（例えば、特許文献１参照）。
【０００４】
また、図１０に示すように、環状の荷重付加部４２、４３と、これを連結する杆部４８を含む連結部材４１で、中央部４５から荷重付加部４２側に位置する接続杆部４４の横断面をほぼ横長四角形状として、荷重が付加したときに応力を分散させて、それらが均等にかかるようにし、中央部４５から荷重付加部４３間に位置する接続杆部４６の横断面をほぼ十字形状として、荷重が付加したときに変形を可能としたものもある（例えば、特許文献２参照）。
【０００５】
【特許文献１】
特開平７−２４２１１１号公報（第２頁第１欄第２〜５行、第２頁第２欄第２７〜３１、図１）
【特許文献２】
特開２０００−１４２０５２号公報（第２頁第１欄第２〜１０行、第３頁第４欄第２４〜３１行、図１、図３）
【０００６】
【発明が解決しようとする課題】
【０００７】
従来の図８（ａ）（ｂ）に示すような連結部材２１は、横断面Ｉ字型の杆部２８の側面にゲート２７を形成した鋳型キャビティとし、この鋳型キャビティ内にアルミニウム合金や球状黒鉛鋳鉄の組成の溶湯がゲート２７を介して注入される。しかし、図８（ｃ）に示すように、ゲート２７から注入された溶湯Ｍは、断面が急変する部分において乱流となり、空気やガスなどを巻き込みやすい。そして、溶湯Ｍが凝固後、連結部材２１にガス欠陥などを発生させるおそれがあり、また、杆部２８の中央付近にゲート２７を形成した場合には、連結部材２１のゲート２７付近の凝固が遅れ、この部分の金属組織が粗くなり、杆部２８の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質を低下させるおそれがある。
【０００８】
図９に示すような連結部材３１を開示している特許文献１には、ゲートの配置や形状寸法についての記載は何も見当たらないが、上述の図８に示す従来の連結部材２１と同様の課題を有する。即ち、ゲートの配置や形状寸法が適切でないと、断面が急変する部分において溶湯が乱流となって空気やガスなどを巻き込みやすく、溶湯が凝固後、連結部材３１にガス欠陥などを発生させるおそれがあり、また、杆部３８の中央付近にゲートを形成した場合には、連結部材３１のゲート付近の凝固が遅れ、この部分の金属組織が粗くなり、杆部３８の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質を低下させるおそれがある。
【０００９】
また、図１０に示すような連結部材４１を開示している特許文献２には、ゲートの配置や形状寸法についての記載は何も見当たらないが、この連結部材４１においても上述の図８に示す従来の連結部材２１と同様の課題を有する。即ち、ゲートの配置や形状寸法が適切でないと、断面が急変する部分において溶湯が乱流となって空気やガスなどを巻き込みやすく、溶湯が凝固後、連結部材４１にガス欠陥などを発生させるおそれがあり、また、杆部４８の中央付近にゲートを形成した場合には、連結部材４１のゲート付近の凝固が遅れ、この部分の金属組織が粗くなり、杆部４８の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質を低下させるおそれがある。
【００１０】
本発明は、上記課題に鑑みてなされたもので、その目的は、両端に位置する荷重付加部と、この荷重付加部を連結する杆部とが、一体に形成された鋳造製連結部材の断面が急変する部分において空気やガスなどの巻き込みを少なくして、溶湯が凝固後、連結部材にガス欠陥などの発生を防止し、また、杆部の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質を確保できる連結部材を得ることにある。
【００１１】
【課題を解決するための手段】
上記課題を解決するため、本発明の連結部材は、両端に位置する環状またはＵ字状の荷重付加部と、前記荷重付加部を連結する杆部とが、一体に形成された鋳造製連結部材であって、前記杆部は、中間に位置する横断面がＨ字型、Ｉ字型、Ｔ字型、Ｕ字型、十字型、Ｏ字型を有する少なくとも１の基本杆部と、前記基本杆部から前記荷重付加部までを接続する横断面が中実の多角形または円形を有する接続杆部とを含み、前記接続杆部にゲートが形成されていることを特徴とする。環状またはＵ字状の荷重付加部は、連結部材の両端の何れか一方、または両方に形成される。なお、基本杆部の横断面の形状は、図２に示すように、（ａ）Ｈ字型、（ｂ）Ｉ字型、（ｃ）Ｔ字型、（ｄ）Ｕ字型、（ｅ）十字型、（ｆ）Ｏ字型でよく、またはこれらを組み合わしてもよく、また、左右反転または斜め回転した形状を含んでもよい。また、接続杆部は、両端に位置する前記荷重付加部のうち、何れか一方の荷重付加部と基本杆部とを接続するものでもよい。
【００１２】
上記構成により、溶湯はゲートを介して横断面が中実の多角形または円形を有する接続杆部に流入する。この際、接続杆部のゲート付近で多少の乱流の発生があっても、接続杆部には断面の急変がないので、溶湯は接続杆部を流動しながら整流される。その後、整流された溶湯は、横断面が凹凸し急変する部分である基本杆部を層流に近い状態で流れるので、空気やガスなどの巻き込みが少なくなる。そして、溶湯が凝固後、連結部材にガス欠陥などの発生を防止する。また、基本杆部にゲートを形成してないので、凝固の遅れにより金属組織が粗くならず、杆部の中央付近は引張強さ、耐力や曲げ強さなどの機械的性質を有し、連結部材としての機能も確保される。
【００１３】
また、本発明の連結部材においては、前記ゲートの幅が、前記接続杆部の幅の１／２以上、望ましくは３／４以上に形成されていることが好ましい。これにより、ゲート付近の接続杆部での溶湯の乱流の発生をさらに少なくし、接続杆部での整流が促進されて、溶湯がより層流に近い状態で基本杆部に流れるので、空気やガスなどの巻き込みがさらに抑制される。
【００１４】
また、本発明の連結部材において、前記基本杆部は、横断面での各肉厚比が１／１．５以下であることが好ましい。これにより、杆部の中央付近の引け巣、不廻り、湯境などの鋳造欠陥の発生を少なくできる。なお、肉厚比とは、図２に示す基本杆部の横断面である（ａ）Ｈ字型、（ｂ）Ｉ字型、（ｃ）Ｔ字型、（ｄ）Ｕ字型、（ｅ）十字型、（ｆ）Ｏ字型での、［縦方向の肉厚（Ｔ１）／横方向の肉厚（Ｔ２）］の比、または「横方向の肉厚（Ｔ２）／縦方向の肉厚（Ｔ１）」の比を言う。
【００１５】
また、本発明の連結部材においては、前記基本杆部から前記接続杆部までを徐変させていることが好ましい。これにより、接続杆部で整流された溶湯の流れを乱すことなく、さらに層流に近い状態で基本杆部に流れるので、空気やガスなどの巻き込みを一層抑制することができる。加えて、基本杆部から接続杆部までを徐変させることで、連結部材として使用する際に、付加された荷重による応力の集中を防ぐことができる。
【００１６】
また、本発明の連結部材において、前記接続杆部は、前記ゲートの取付け部および該取付け部に向い合うゲート投影部を除いて、横断面を凹状に窪ませていることが好ましい。これにより、ゲートの取付け部および該取付け部に向い合うゲート投影部が平面なのでゲート付近の接続杆部での溶湯の乱流の発生を少なくできるとともに、横断面を凹状に窪ませているので、連結部材を軽量にすることができる。
【００１７】
また、本発明の連結部材は、両端に位置する環状の荷重付加部と、前記荷重付加部を連結する杆部とが、一体に形成した鋳造製連結部材であって、前記杆部は、中間に位置する横断面がＩ字型を有する基本杆部と、前記基本杆部から前記荷重付加部までの横断面が中実の四角形または円形を有する接続杆部とを含み、前記接続杆部に該接続杆部の幅の３／４以上の幅のゲートが形成されていることを特徴とする。
【００１８】
【発明の実施の形態】
以下、発明の実施の形態を詳細に説明する。
（実施の形態１）
図１は、実施の形態１での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ａ−Ａ、（ｄ）は（ｂ）での断面Ｂ−Ｂ、（ｅ）は（ｂ）での断面Ｃ−Ｃ、（ｆ）は溶湯の流れを示す模式図である。図１（ａ）（ｂ）で、連結部材１は、両端に位置する環状の荷重付加部２、３と、この荷重付加部２、３を連結する杆部８とが、鋳造で一体に形成されている。また、杆部８は、中間に位置する横断面がＩ字型を有する基本杆部５と、この基本杆部５から荷重付加部２、３までを接続する横断面が中実の四角形を有する接続杆部４、６とを含み、一方の接続杆部６にゲート７が形成されている。Ｉ字型の基本杆部５は、図１（ａ）（ｄ）に示すように、幅をＷ３、高さをＨ、肉厚をＴ１、Ｔ２として、引張、曲げ、ねじり荷重に対応できるようにしている。また、接続杆部４は、図１（ａ）（ｃ）に示すように、幅をＷ４、高さをＨとした横断面を中実の四角形にしている。また、接続杆部６は、図１（ａ）（ｅ）に示すように、幅をＷ１、高さをＨとした横断面を中実の四角形にしている。なお、図１（ａ）の符号ＰＬで示す一点鎖線は、鋳造における鋳型の分割面となる見切り線（Ｐａｒｔｉｎｇ Ｌｉｎｅ）である。
【００１９】
そして、一方の接続杆部６に、この接続杆部６の幅Ｗ１の３／４以上の幅Ｗ２としたゲート７を形成している。また、基本杆部５の横断面での各肉厚Ｔ１、Ｔ２の比を１／１．５以下とし、基本杆部５から接続杆部４、６までを徐変させている。また、ゲート７の左端Ｐ１を、基本杆部５から接続杆部６まで徐変させた終点Ｐ２に略一致させ、ゲート７が基本杆部５に跨らないように形成している。
【００２０】
実施の形態１によれば、ゲート７を中実で四角形の横断面を有する接続杆部６に、基本杆部５に跨らないように形成しているので、図１（ｆ）に示すように、ゲート７を介して流入した溶湯Ｍは、接続杆部６のゲート７付近では多少の乱流の発生はあるが、接続杆部６で整流され、横断面が凹凸し急変している基本杆部５では層流に近い状態で流れるので空気やガスなどの巻き込みが少なくなる。そして、溶湯Ｍが凝固後、連結部材１にガス欠陥などの発生が防止される。また、基本杆部５にゲート７を形成してないので、凝固の遅れにより金属組織が粗くならず、杆部８の中央付近は引張強さ、耐力や曲げ強さなどの機械的性質を有し、連結部材１としての機能も確保される。
【００２１】
（実施の形態２）
図３は、実施の形態２での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ｃ−Ｃである。図３（ａ）（ｂ）で、連結部材１は、一端に位置するＵ字状の荷重付加部２と、他端に位置する環状の荷重付加部３と、この荷重付加部２、３を連結する杆部８とが、鋳造で一体に形成されている。杆部８は、中間に位置する横断面がＩ字型を有する基本杆部５と、この基本杆部５から荷重付加部２、３までを接続する横断面が中実の楕円形を有する接続杆部４、６とを含み、一方の接続杆部６にゲート７を形成している。また、基本杆部５には他部材の取付ボス５ａおよびネジ孔５ｂを形成している。ゲート７の幅Ｗ２は、接続杆部６の幅Ｗ１の１／２以上としている。また、基本杆部５の横断面での各肉厚比を、前述した実施の形態１と同様に１／１．５以下とし、基本杆部５から接続杆部４、６までを徐変させている。
【００２２】
実施の形態２によれば、実施の形態１と同様に、ゲート７を介して流入した溶湯は、接続杆部６のゲート７付近では多少の乱流の発生はあるが、中実で楕円形の横断面を有する接続杆部６で整流され、横断面が凹凸し急変している基本杆部５では層流に近い状態で流れるので空気やガスなどの巻き込みが少なくなる。そして、溶湯が凝固後、連結部材１にガス欠陥などの発生が防止される。また、基本杆部５にゲート７を形成してないので、凝固の遅れにより金属組織が粗くならず、杆部８の中央付近は引張強さ、耐力や曲げ強さなどの機械的性質を有し、連結部材１としての機能も確保される。
【００２３】
（実施の形態３）
図４は、実施の形態３での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ｃ−Ｃである。図４（ａ）（ｂ）で、連結部材１は、両端に位置する環状の荷重付加部２、３と、この荷重付加部２、３を連結する側面視で「くの字状」の杆部８とが、鋳造で一体に形成されている。また、杆部８は、中間に位置する横断面がＩ字型を有する基本杆部５と、この基本杆部５から荷重付加部２、３までを接続する横断面が中実の四角形を有する接続杆部４、６とを含み、一方の接続杆部６に、接続杆部６の幅Ｗ１の３／４以上の幅Ｗ２のゲート７を形成している。また、基本杆部５の横断面での各肉厚比を１／１．５以下とし、基本杆部５から接続杆部４、６までを徐変させている。
【００２４】
また、接続杆部６は、その横断面を、図４に示すように、ゲート７の取付け部６１および該取付け部に向い合うゲート投影部６２は平面とし、この６１、６２を除いた部位には凹状に窪み６ａ、６ｂ、６ｃ、６ｄを形成している。これにより、６１、６２を平面として、接続杆部６のゲート７付近での溶湯の乱流の発生を抑えた上で、横断面を凹状に窪ませることで連結部材１を軽量にしている。図示しないが、接続杆部４も横断面を凹状に窪ませれば、さらに、連結部材１を軽量にできる。
【００２５】
実施の形態３によれば、実施の形態１と同様に、ゲート７を介して流入した溶湯は、接続杆部６のゲート７付近では多少の乱流の発生はあるが、中実で四角形の横断面を有する接続杆部６で整流され、横断面が凹凸し急変している基本杆部５では層流に近い状態で流れるので空気やガスなどの巻き込みが少なくなる。そして、溶湯が凝固後、連結部材１にガス欠陥などの発生が防止される。また、基本杆部５にゲート７を形成してないので、凝固の遅れにより金属組織が粗くならず、杆部８の中央付近は引張強さ、耐力や曲げ強さなどの機械的性質を有し、連結部材１としての機能も確保される。
【００２６】
上記、実施の形態１〜３では、杆部８の一方の接続杆部６にゲート７を形成する事例を示したが、本発明の連結部材１は、接続杆部６に替えて接続杆部４にゲート７を形成しても同様の作用効果が得られる。
【００２７】
【実施例】
（実施例１）
前述の実施の形態１の図１に示す連結部材１の材質を（ＪＩＳ）ＡＣ４ＣＨ材として、湯流れ凝固シミュレーション行い、さらに低圧鋳造法により鋳造した。図６で、（ａ）は連結部材１、１１ほかのキャビティが形成された金型９のモデルの平面図、（ｂ）は（ａ）のＡ部（実施例１のゲート７付近）での湯流れの模式図、（ｃ）は（ａ）のＢ部（後述する比較例２の連結部材１１のゲート１７付近）での湯流れの模式図である。連結部材１は、図１での環状の荷重付加部２、３のピッチＰを３００ｍｍ、外径Ｄを４６ｍｍ、内径ｄを３０ｍｍ、接続杆部４、６の幅Ｗ４、Ｗ１を何れも３０ｍｍ、基本杆部５の幅Ｗ３を４０ｍｍ、接続杆部４、６および基本杆部５の高さＨを４０ｍｍとした。また、ゲート７は、幅Ｗ２を接続杆部６の幅Ｗ１の３／４以上となる２５ｍｍ、長さＬ１を４０ｍｍとし、ゲート７の左端Ｐ１を、基本杆部５から接続杆部６まで徐変させた終点Ｐ２に略一致させた。そして、基本杆部５の肉厚Ｔ１、Ｔ２をそれぞれ、７．５ｍｍ、１０ｍｍ、１２．５ｍｍと変えて、湯口９ａを経由しゲート７から溶湯を注入させた。
【００２８】
湯流れ凝固シミュレーションの結果、図６（ｂ）に示すように、ゲート７を介して流入した溶湯Ｍは、接続杆部６のゲート７付近では多少の乱流の発生はあるが、接続杆部６で整流され、横断面が凹凸し急変している基本杆部５では層流に近い状態で流れることがわかった。
【００２９】
一方、湯流れ凝固シミュレーションにより、杆部８の中央付近での鋳造欠陥の発生の状況を調べてみた。その結果を纏めて図７に示す。図７から、鋳造欠陥の発生が見られずＯＫ（○）と判定された連結部材１は、（イ）肉厚Ｔ１または肉厚Ｔ２が７．５または１０ｍｍで、肉厚比Ｔ１／Ｔ２またはＴ２／Ｔ１が１〜１．３３、（ロ）肉厚Ｔ１が１０ｍｍ、肉厚Ｔ２が１２．５ｍｍで、肉厚比Ｔ２／Ｔ１が１．２５、（ハ）肉厚Ｔ１が１２．５ｍｍ、肉厚Ｔ２が１０ｍｍまたは１２．５ｍｍで、肉厚比Ｔ１／Ｔ２またはＴ２／Ｔ１が１〜１．２５のものであった。一方、肉厚Ｔ２に鋳造欠陥の発生が見られＮＧ（×）と判定された連結部材１は、（ニ）肉厚Ｔ１が７．５ｍｍ、肉厚Ｔ２が１２．５ｍｍで、肉厚比Ｔ２／Ｔ１が１．６７のものであった。また、肉厚Ｔ１の中央部に微小な鋳造欠陥の発生が見られたが機能上ＯＫ（△）と判定された連結部材１は、（ホ）肉厚Ｔ１が１２．５ｍｍ、肉厚Ｔ２が７．５ｍｍで、肉厚比Ｔ１／Ｔ２が１．６７のものであった。以上のことから、肉厚比Ｔ１／Ｔ２またはＴ２／Ｔ１が１．５以下であれば、鋳造欠陥の発生を防止できて、連結部材１としての機能を確保できることがわかった。
【００３０】
（比較例１）
比較例１として、実施例１の連結部材１でのゲート７の幅Ｗ２を、接続杆部６の幅Ｗ１（３０ｍｍ）の１／３となる１０ｍｍとした以外は実施例１と同一の構成として、図１に示す連結部材１の湯流れ凝固シミュレーションを行い、さらに低圧鋳造法により鋳造した。湯流れ凝固シミュレーションの結果、ゲート７から流入した溶湯は、接続杆部６のゲート７付近で乱流を発生し、接続杆部６で整流されず、乱流のまま基本杆部５を流動し、空気やガスなどの巻き込みによるガス欠陥などの鋳造欠陥の発生が懸念された。これは、接続杆部６の幅Ｗ１に対しゲート７の幅Ｗ２を１／２未満に小さく形成したことで、ゲート７と接続杆部６とで断面が急変したこと、即ち、断面の変化が大きいことに起因すると考えられた。
【００３１】
以上の実施例１の連結部材１と、比較例１の連結部材１から試験片を切り出し、引張強さ（ＭＰａ）、耐力（ＭＰａ）、伸び（％）の機械的性質を測定した。その結果を表１に示す。
【００３２】
【表１】
【００３３】
表１から、ゲートＷ２の幅が接続杆部Ｗ１の幅の３／４以上の２．５／３に形成した実施例１の連結部材１は、両者の幅の比を３／４未満の１／３に形成した比較例１の連結部材１に対して、特に伸びの機械的特性が良くなり、しかも、ばらつきが少ないこともわかった。
【００３４】
（比較例２）
比較例２として、図５に示す連結部材１１を（ＪＩＳ）ＡＣ４ＣＨ材として、前述した図６（ａ）に示す金型９のモデルを用いて、湯流れ凝固シミュレーションを行い、さらに低圧鋳造法により鋳造した。図５は比較例２の連結部材１１であり、（ａ）は平面図、（ｂ）は側面図である。なお、図５、図６で実施例１と同一の構成要素には同一の符号を付し、重複した説明を省略する。比較例２の連結部材１１は、基本杆部５の肉厚Ｔ１とＴ２を何れも１２．５ｍｍ（肉厚比Ｔ１／Ｔ２＝１．０）とし、ゲート１７を接続杆部６ではなく基本杆部５の中央付近に形成した以外は実施例１と同一の構成とした。
【００３５】
比較例２の湯流れ凝固シミュレーションの結果、図６（ｃ）に示すように、ゲート１７を介して流入した溶湯Ｍは、ゲート１７から横断面が凹凸し急変している基本杆部５でその流れが乱流となり、空気やガスなどの巻き込みによるガス欠陥などの鋳造欠陥の発生が懸念された。また、基本杆部５の中央付近にゲート１７を形成すると、ゲート１７付近の凝固が遅れ、この部分の金属組織が粗くなり、杆部８の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質が低下し、連結部材１１としての機能を損なうことが予想された。
【００３６】
なお、実施例１、比較例１、２では、低圧鋳造法で（ＪＩＳ）ＡＣ４ＣＨ組成アルミニウム合金の湯流れ凝固シミュレーションおよび鋳造を行ったが、通常のダイカスト法、真空ダイカスト法、または溶湯鍛造法など、他の金型鋳造法で連結部材を鋳造しても、上記と同様に、ゲートの配置や寸法により溶湯が乱流または層流になったり、基本杆部の肉厚比により鋳造欠陥の発生が有ったり無かったりすると予想された。
【００３７】
【発明の効果】
以上詳細に説明のとおり、本発明の連結部材によれば、両端に位置する環状またはＵ字状の荷重付加部と、前記荷重付加部を連結する杆部とが、一体で形成した連結部材の断面が急変する部分において空気やガスなどの巻き込みを少なくして、溶湯が凝固後、連結部材にガス欠陥などの発生を防止し、また、杆部の中央付近の引張強さ、耐力や曲げ強さなどの機械的性質を確保できる。
【図面の簡単な説明】
【図１】実施の形態１での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ａ−Ａ、（ｄ）は（ｂ）での断面Ｂ−Ｂ、（ｅ）は（ｂ）での断面Ｃ−Ｃ、（ｆ）は溶湯の流れを示す模式図である。
【図２】基本杆部の横断面での（ａ）Ｈ字型、（ｂ）Ｉ字型、（ｃ）Ｔ字型、（ｄ）Ｕ字型、（ｅ）十字型、（ｆ）Ｏ字型と、肉厚Ｔ１、Ｔ２を示す図である。
【図３】実施の形態２での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ｃ−Ｃである。
【図４】実施の形態３での連結部材１を示し、（ａ）はその平面図、（ｂ）は側面図、（ｃ）は（ｂ）での断面Ｃ−Ｃである。
【図５】比較例２の連結部材１１であり、（ａ）は平面図、（ｂ）は側面図である。
【図６】（ａ）は連結部材１ほかのキャビティが形成された金型９のモデルの平面図、（ｂ）は（ａ）のＡ部（実施例１のゲート７付近）での湯流れの模式図、（ｃ）は（ａ）のＢ部（比較例２のゲート１７付近）での湯流れの模式図である。
【図７】湯流れ凝固シミュレーションにより、杆部８の中央付近での鋳造欠陥の発生の状況を調べた結果を示す図である。
【図８】従来の連結部材２１を示し、（ａ）は平面図、（ｂ）は側面図、（ｃ）は鋳造時の（ｂ）の断面Ｅ−Ｅでの溶湯の流れを示す模式図である。
【図９】従来の別の例の連結部材３１を示し、（ａ）は平面図、（ｂ）は（ａ）での断面Ａ−Ａを示す図である。
【図１０】従来のさらに別の例の連結部材４１の斜視図である。
【符号の説明】
１、１１、２１、３１、４１：連結部材（鋳造製連結部材）
２、３、２２、２３、３２、３３、４２、４３：荷重付加部
４、６、４４、４６：接続杆部
６１：ゲートの取付け部
６２：ゲートの取付け部に向い合うゲート投影部
６ａ、６ｂ、６ｃ、６ｄ：窪み
５：基本杆部
４５：中央部
７、１７、２７：ゲート
８、２８、３８、４８：杆部
９：金型
９ａ：湯口
Ｗ１、Ｗ４：接続杆部の幅
Ｗ３：基本杆部の幅
Ｗ２：ゲートの幅
Ｈ：高さ
Ｌ１：長さ
Ｔ１、Ｔ２：肉厚
Ｍ：溶湯
ＰＬ：見切り線[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cast connecting member in which a load applying portion located at both ends and a rod portion connecting the load applying portion are integrally formed.
[0002]
[Prior art]
FIGS. 8A and 8B show a conventional connection member 21 made by casting (hereinafter, simply referred to as a “connection member”), wherein FIG. 8A is a plan view, FIG. 8B is a side view, and FIG. It is a schematic diagram which shows the flow of the molten metal in the cross section EE. 9A and 9B show another example of a conventional connection member 31, wherein FIG. 9A is a plan view, and FIG. 9B is a view showing a cross section AA in FIG. 9A. FIG. 10 is a perspective view of still another example of the connection member 41 of the related art. 8 (a) and 8 (b), the connecting member 21 has annular load applying portions 22 and 23 located at both ends and a rod portion 28 having an I-shaped cross section connecting the load applying portions 22 and 23. And are integrally formed by casting. The connecting member 21 is subjected to repeated loads, such as tension, compression, and bending, on the load applying portions 22 and 23.
[0003]
As shown in FIGS. 9 (a) and 9 (b), annular connecting members 32, 33 located at both ends and a rod 38 connecting the connecting members 32, 33 are integrally formed as an integral connecting member. In the connecting member 31 formed as described above, there is one in which a bending stress suppressing portion 39 is formed in the rod portion 38 to reduce the weight and improve the durability (for example, see Patent Document 1).
[0004]
As shown in FIG. 10, a connecting member 41 including annular load applying portions 42, 43 and a rod portion 48 connecting the annular load applying portions 42, 43 serves as a connecting rod portion 44 located on the load applying portion 42 side from a central portion 45. The cross section is made into a substantially oblong rectangular shape, and when a load is applied, the stress is dispersed so that they are evenly applied. The cross section of the connecting rod portion 46 located between the central portion 45 and the load applying portion 43 is substantially formed. There is also a cross shape that can be deformed when a load is applied (for example, see Patent Document 2).
[0005]
[Patent Document 1]
JP-A-7-242111 (page 2, column 1, lines 2 to 5, page 2, column 2, 27 to 31, FIG. 1)
[Patent Document 2]
JP-A-2000-142052 (page 2, column 1, lines 2-10, page 3, column 4, lines 24-31, FIGS. 1, 3)
[0006]
[Problems to be solved by the invention]
[0007]
A conventional connecting member 21 as shown in FIGS. 8A and 8B is a mold cavity in which a gate 27 is formed on a side surface of a rod portion 28 having an I-shaped cross section, and an aluminum alloy or spheroidal graphite is provided in the mold cavity. A melt of cast iron composition is injected through the gate 27. However, as shown in FIG. 8C, the molten metal M injected from the gate 27 becomes a turbulent flow in a portion where the cross section changes suddenly, and is easily entrained in air or gas. Then, after the molten metal M solidifies, there is a possibility that a gas defect or the like may be generated in the connecting member 21, and when the gate 27 is formed near the center of the rod portion 28, solidification near the gate 27 of the connecting member 21 may occur. As a result, the metal structure of this portion becomes coarse, and mechanical properties such as tensile strength, proof stress and bending strength near the center of the rod portion 28 may be reduced.
[0008]
In Patent Document 1 which discloses the connecting member 31 as shown in FIG. 9, there is no description about the arrangement and the shape and dimensions of the gate, but the same as the conventional connecting member 21 shown in FIG. Have issues. That is, if the arrangement and the shape and dimensions of the gates are not appropriate, the molten metal becomes turbulent in the portion where the cross section changes suddenly, so that air and gas are likely to be entrained. When a gate is formed near the center of the rod 38, solidification near the gate of the connecting member 31 is delayed, the metal structure of this portion becomes coarse, and the tensile strength near the center of the rod 38 is increased. , Mechanical properties such as proof stress and bending strength may be reduced.
[0009]
Further, in Patent Literature 2, which discloses a connecting member 41 as shown in FIG. 10, there is no description about the arrangement and the shape and dimensions of the gate, but this connecting member 41 is also shown in FIG. It has the same problem as the conventional connecting member 21. That is, if the arrangement and the shape and dimensions of the gates are not appropriate, the molten metal becomes turbulent in the portion where the cross section changes suddenly, so that air or gas is easily entrained. When a gate is formed near the center of the rod portion 48, solidification near the gate of the connecting member 41 is delayed, the metal structure in this portion becomes coarse, and the tensile strength near the center of the rod portion 48 is increased. , Mechanical properties such as proof stress and bending strength may be reduced.
[0010]
The present invention has been made in view of the above problems, and has as its object to provide a cross section of a cast connecting member in which a load applying portion located at both ends and a rod portion connecting the load applying portion are integrally formed. Reduces the entrainment of air and gas in the part where the temperature changes suddenly, prevents the gas from solidifying after the melt solidifies, and prevents the occurrence of gas defects, etc., and also the tensile strength, proof stress and bending strength near the center of the rod. It is another object of the present invention to obtain a connecting member that can secure mechanical properties such as the above.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, a connecting member according to the present invention is a cast connecting member in which an annular or U-shaped load applying portion located at both ends and a rod portion connecting the load applying portion are integrally formed. Wherein the rod portion has at least one basic rod portion having a middle cross section having an H shape, an I shape, a T shape, a U shape, a cross shape, and an O shape; A cross section connecting the rod portion to the load applying portion includes a connecting rod portion having a solid polygonal or circular shape, and a gate is formed on the connecting rod portion. The annular or U-shaped load applying portion is formed on one or both ends of the connecting member. As shown in FIG. 2, the cross-sectional shape of the basic rod portion is (a) H-shaped, (b) I-shaped, (c) T-shaped, (d) U-shaped, and (e). The shape may be a cross shape, (f) an O-shape, or a combination thereof, and may include a shape that is horizontally inverted or obliquely rotated. Further, the connecting rod portion may connect any one of the load applying portions located at both ends to the basic rod portion.
[0012]
With the above configuration, the molten metal flows into the connecting rod portion having a solid polygonal or circular cross section through the gate. At this time, even if some turbulence occurs near the gate of the connecting rod, the molten metal is rectified while flowing through the connecting rod because there is no sudden change in the cross section of the connecting rod. After that, the rectified molten metal flows through the basic rod portion, which is a portion where the cross section is uneven and changes suddenly, in a state close to laminar flow, so that entrainment of air and gas is reduced. Then, after the molten metal is solidified, occurrence of gas defects or the like in the connecting member is prevented. In addition, since the gate is not formed on the basic rod, the metal structure does not become coarse due to the delay of solidification, and the center of the rod has mechanical properties such as tensile strength, proof strength, bending strength, etc. The function as a member is also ensured.
[0013]
Further, in the connecting member of the present invention, it is preferable that the width of the gate is formed to be 以上 or more, preferably ３ or more of the width of the connecting rod portion. This further reduces the occurrence of turbulence of the molten metal at the connecting rod near the gate, promotes rectification at the connecting rod, and allows the molten metal to flow to the basic rod in a state closer to laminar flow. Entrapment of gas and gas is further suppressed.
[0014]
Further, in the connecting member of the present invention, it is preferable that each basic rod portion has a thickness ratio of 1 / 1.5 or less in a transverse cross section. As a result, the occurrence of casting defects such as shrinkage cavities near the center of the rod portion, turning around, and a hot junction can be reduced. The wall thickness ratio is a cross section of the basic rod portion shown in FIG. 2, (a) H shape, (b) I shape, (c) T shape, (d) U shape, (e) ) The ratio of [thickness in the vertical direction (T1) / thickness in the horizontal direction (T2)] or "thickness in the horizontal direction (T2) / thickness in the vertical direction" in the cross shape and (f) O-shape. Thickness (T1) ".
[0015]
In the connecting member of the present invention, it is preferable that the distance from the basic rod to the connecting rod is gradually changed. Thereby, the flow of the molten metal rectified by the connecting rod portion flows into the basic rod portion in a state close to laminar flow without disturbing the flow of the molten metal, so that entrainment of air, gas, and the like can be further suppressed. In addition, by gradually changing from the basic rod portion to the connecting rod portion, it is possible to prevent concentration of stress due to an applied load when used as a connecting member.
[0016]
Further, in the connecting member of the present invention, it is preferable that the connecting rod portion has a concave cross section excluding a mounting portion of the gate and a gate projection portion facing the mounting portion. Thereby, since the mounting portion of the gate and the gate projection portion facing the mounting portion are flat, the occurrence of turbulent flow of the molten metal at the connecting rod portion near the gate can be reduced, and the cross section is concavely concave. The connecting member can be reduced in weight.
[0017]
Further, the connecting member of the present invention is a cast connecting member in which an annular load applying portion located at both ends and a rod portion connecting the load applying portion are integrally formed, and the rod portion is an intermediate member. And a connecting rod portion having a solid square or circular cross section from the basic rod portion to the load applying portion, wherein the connecting rod portion has an I-shaped cross section. A gate having a width of at least 3/4 of the width of the connecting rod portion is formed.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the invention will be described in detail.
(Embodiment 1)
1A and 1B show a connecting member 1 according to the first embodiment, wherein FIG. 1A is a plan view, FIG. 1B is a side view, FIG. 1C is a cross section AA in FIG. FIG. 3B is a schematic view showing a cross section BB, FIG. 4E is a schematic view showing a cross section CC in FIG. 4B, and FIG. 1 (a) and 1 (b), in a connecting member 1, annular load applying portions 2, 3 located at both ends and a rod portion 8 connecting the load applying portions 2, 3 are integrally formed by casting. Have been. Further, the rod portion 8 has a basic rod portion 5 having an I-shaped cross section located at the middle, and a solid rectangular cross section connecting the basic rod portion 5 to the load applying portions 2 and 3. One of the connecting rods 6 is provided with a gate 7. As shown in FIGS. 1 (a) and 1 (d), the I-shaped basic rod portion 5 has a width of W3, a height of H, and a thickness of T1 and T2 so as to cope with tension, bending and torsion loads. I have to. Further, as shown in FIGS. 1 (a) and 1 (c), the connecting rod 4 has a solid rectangular cross section with a width of W4 and a height of H. Further, as shown in FIGS. 1A and 1E, the connecting rod portion 6 has a solid rectangular cross section with a width W1 and a height H. Note that a dashed line indicated by a symbol PL in FIG. 1A is a parting line (Parting Line) serving as a dividing surface of a mold in casting.
[0019]
Further, a gate 7 having a width W2 that is equal to or more than Ｗ of the width W1 of the connecting rod 6 is formed on one connecting rod 6. Further, the ratio of the thicknesses T1 and T2 in the cross section of the basic rod 5 is set to 1 / 1.5 or less, and the distance from the basic rod 5 to the connecting rods 4 and 6 is gradually changed. Further, the left end P1 of the gate 7 is made substantially coincident with an end point P2 that is gradually changed from the basic rod 5 to the connecting rod 6, so that the gate 7 does not straddle the basic rod 5.
[0020]
According to the first embodiment, since the gate 7 is formed on the connecting rod portion 6 having a solid and rectangular cross section so as not to straddle the basic rod portion 5, as shown in FIG. The molten metal M flowing in through the gate 7 has some turbulence near the gate 7 of the connecting rod 6, but is rectified by the connecting rod 6, and has a sudden change in its cross section. Since the rod portion 5 flows in a state close to laminar flow, entrainment of air, gas and the like is reduced. After the molten metal M solidifies, the occurrence of gas defects and the like in the connecting member 1 is prevented. Further, since the gate 7 is not formed in the basic rod 5, the metal structure does not become coarse due to the delay of solidification, and the center of the rod 8 has mechanical properties such as tensile strength, proof stress and bending strength. In addition, the function as the connecting member 1 is also ensured.
[0021]
(Embodiment 2)
3A and 3B show a connecting member 1 according to the second embodiment, in which FIG. 3A is a plan view, FIG. 3B is a side view, and FIG. 3C is a cross section CC in FIG. 3A and 3B, the connecting member 1 includes a U-shaped load applying portion 2 located at one end, an annular load applying portion 3 located at the other end, and the load applying portions 2 and 3. The connecting rod 8 is integrally formed by casting. The rod portion 8 includes a basic rod portion 5 having an I-shaped cross section located in the middle, and a connection having a solid elliptical cross section connecting the basic rod portion 5 to the load applying portions 2 and 3. A gate 7 is formed on one connecting rod 6 including the rods 4 and 6. Further, the basic rod 5 is formed with a mounting boss 5a and a screw hole 5b of another member. The width W2 of the gate 7 is equal to or more than の of the width W1 of the connecting rod 6. Also, the thickness ratio of each of the basic rods 5 in the cross section in the cross section is set to 1 / 1.5 or less similarly to the first embodiment, and the basic rods 5 to the connecting rods 4 and 6 are gradually changed. ing.
[0022]
According to the second embodiment, as in the first embodiment, the molten metal flowing in through the gate 7 has some turbulence near the gate 7 of the connecting rod 6, but is solid and elliptical. In the basic rod portion 5, which is rectified by the connecting rod portion 6 having a horizontal cross section and has a suddenly changing cross section, flows in a state close to laminar flow, so that entrainment of air and gas is reduced. After the molten metal is solidified, the occurrence of gas defects and the like in the connecting member 1 is prevented. Further, since the gate 7 is not formed in the basic rod 5, the metal structure does not become coarse due to the delay of solidification, and the center of the rod 8 has mechanical properties such as tensile strength, proof stress and bending strength. In addition, the function as the connecting member 1 is also secured.
[0023]
(Embodiment 3)
4A and 4B show the connecting member 1 according to the third embodiment, in which FIG. 4A is a plan view, FIG. 4B is a side view, and FIG. 4C is a cross section CC in FIG. 4 (a) and 4 (b), the connecting member 1 has annular load applying portions 2 and 3 located at both ends, and a "L-shaped" rod in a side view connecting the load applying portions 2 and 3. The part 8 is integrally formed by casting. Further, the rod portion 8 has a basic rod portion 5 having an I-shaped cross section located at the middle, and a solid rectangular cross section connecting the basic rod portion 5 to the load applying portions 2 and 3. A gate 7 having a width W2 equal to or more than ／ of the width W1 of the connection rod 6 is formed on one of the connection rods 6. In addition, the thickness ratio of each of the basic rods 5 in the transverse cross section is set to 1 / 1.5 or less, and the distance from the basic rods 5 to the connecting rods 4 and 6 is gradually changed.
[0024]
As shown in FIG. 4, the connecting rod portion 6 has a horizontal section in which a mounting portion 61 of the gate 7 and a gate projection portion 62 facing the mounting portion are flat surfaces. Have concave portions 6a, 6b, 6c and 6d formed in a concave shape. Thereby, the turbulence of the molten metal near the gate 7 of the connecting rod 6 is suppressed by setting the planes 61 and 62 as flat surfaces, and the connecting member 1 is reduced in weight by making the cross section concave. Although not shown, if the connecting rod portion 4 is also depressed in a transverse cross section, the weight of the connecting member 1 can be further reduced.
[0025]
According to the third embodiment, as in the first embodiment, the molten metal flowing in through the gate 7 has some turbulence near the gate 7 of the connecting rod 6, but has a solid and rectangular shape. In the basic rod portion 5, which is rectified by the connecting rod portion 6 having a cross section and has a suddenly changing cross section, flows in a state close to laminar flow, so that entrainment of air or gas is reduced. After the molten metal is solidified, the occurrence of gas defects and the like in the connecting member 1 is prevented. Further, since the gate 7 is not formed in the basic rod 5, the metal structure does not become coarse due to the delay of solidification, and the center of the rod 8 has mechanical properties such as tensile strength, proof stress and bending strength. In addition, the function as the connecting member 1 is also secured.
[0026]
In the above-described first to third embodiments, the case where the gate 7 is formed on one connecting rod 6 of the rod 8 has been described. However, the connecting member 1 of the present invention is different from the connecting rod 6 in that the connecting rod 6 is replaced with the connecting rod 6. The same operation and effect can be obtained even if the gate 7 is formed on the gate 4.
[0027]
【Example】
(Example 1)
Using the material of the connecting member 1 shown in FIG. 1 of the first embodiment shown in FIG. 1 as a (JIS) AC4CH material, a molten metal solidification simulation was performed, and the material was cast by a low pressure casting method. 6A is a plan view of a model of the mold 9 in which the connecting members 1 and 11 and other cavities are formed, and FIG. 6B is a view of a portion A of FIG. 6A (near the gate 7 of the first embodiment). FIG. 3C is a schematic diagram of the hot water flow in a portion B of FIG. 3A (near the gate 17 of the connecting member 11 of Comparative Example 2 described later). The connecting member 1 has a pitch P of the annular load applying portions 2 and 3 in FIG. 1 of 300 mm, an outer diameter D of 46 mm, an inner diameter d of 30 mm, and widths W4 and W1 of the connecting rods 4 and 6 of 30 mm. The width W3 of the basic rod 5 was 40 mm, and the height H of the connecting rods 4, 6 and 5 was 40 mm. The gate 7 has a width W2 of 25 mm, which is at least ／ of the width W1 of the connecting rod 6, a length L1 of 40 mm, and gradually moves the left end P1 of the gate 7 from the basic rod 5 to the connecting rod 6. It almost coincided with the changed end point P2. Then, the thickness T1, T2 of the basic rod portion 5 was changed to 7.5 mm, 10 mm, and 12.5 mm, respectively, and molten metal was injected from the gate 7 through the gate 9a.
[0028]
As a result of the molten metal solidification simulation, as shown in FIG. 6 (b), the molten metal M flowing through the gate 7 has some turbulence near the gate 7 of the connecting rod 6, but the connecting rod 6, the basic rod portion 5 whose flow cross section is uneven and has a sudden change in cross section is found to flow in a state close to laminar flow.
[0029]
On the other hand, the state of the occurrence of casting defects near the center of the rod portion 8 was examined by a molten metal flow solidification simulation. The results are summarized in FIG. From FIG. 7, the connection member 1 in which no casting defect was found and which was determined to be OK (O) was (A) the wall thickness T1 or the wall thickness T2 was 7.5 or 10 mm, and the wall thickness ratio T1 / T2 or T2 / T1 is 1 to 1.33, (b) thickness T1 is 10 mm, thickness T2 is 12.5 mm, thickness ratio T2 / T1 is 1.25, (c) thickness T1 is 12.5 mm, The thickness T2 was 10 mm or 12.5 mm, and the thickness ratio T1 / T2 or T2 / T1 was 1 to 1.25. On the other hand, for the connecting member 1 which was determined to be NG (×) due to occurrence of casting defects in the thickness T2, (d) the thickness T1 was 7.5 mm, the thickness T2 was 12.5 mm, and the thickness ratio T2 / T1 was 1.67. Although a minute casting defect was observed at the center of the thickness T1, the connection member 1 which was functionally determined to be OK (△) has (e) a thickness T1 of 12.5 mm and a thickness T2 of 7.5 mm, and the thickness ratio T1 / T2 was 1.67. From the above, it was found that when the thickness ratio T1 / T2 or T2 / T1 was 1.5 or less, occurrence of casting defects could be prevented, and the function as the connecting member 1 could be secured.
[0030]
(Comparative Example 1)
Comparative Example 1 has the same configuration as that of Example 1 except that the width W2 of the gate 7 of the connecting member 1 of Example 1 is set to 10 mm, which is 1/3 of the width W1 (30 mm) of the connecting rod 6. A simulation of the flow solidification of the connecting member 1 shown in FIG. 1 was performed, and the connection member 1 was cast by a low-pressure casting method. As a result of the molten metal flow solidification simulation, the molten metal flowing from the gate 7 generates a turbulent flow near the gate 7 of the connecting rod 6 and is not rectified by the connecting rod 6, but flows through the basic rod 5 as a turbulent flow. There is a concern that casting defects such as gas defects due to entrainment of air or gas may occur. This is because the width W2 of the connecting rod 6 is made smaller than the width W2 of the connecting rod 6, so that the cross section of the gate 7 and the connecting rod 6 suddenly changes. It was thought to be due to the greatness.
[0031]
Test pieces were cut out from the connecting member 1 of Example 1 and the connecting member 1 of Comparative Example 1, and the mechanical properties such as tensile strength (MPa), proof stress (MPa), and elongation (%) were measured. Table 1 shows the results.
[0032]
[Table 1]
[0033]
From Table 1, it can be seen that the connecting member 1 according to the first embodiment in which the width of the gate W2 is formed to be 2.5 / 3, which is 3/4 or more of the width of the connecting rod portion W1, has a ratio of the widths of 1 to less than 3/4. Compared with the connecting member 1 of Comparative Example 1 formed at / 3, it was also found that the mechanical properties of elongation were particularly improved, and that the dispersion was small.
[0034]
(Comparative Example 2)
As a comparative example 2, using the connecting member 11 shown in FIG. 5 as a (JIS) AC4CH material and using a model of the mold 9 shown in FIG. Cast. 5A and 5B show a connecting member 11 of Comparative Example 2, wherein FIG. 5A is a plan view and FIG. 5B is a side view. In FIGS. 5 and 6, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted. The connecting member 11 of Comparative Example 2 has the thickness T1 and T2 of the basic rod 5 both set to 12.5 mm (thickness ratio T1 / T2 = 1.0), and the gate 17 is not the basic rod but the connecting rod 6. The configuration was the same as that of Example 1 except that it was formed near the center of the portion 5.
[0035]
As a result of the molten metal solidification simulation of Comparative Example 2, as shown in FIG. 6 (c), the molten metal M flowing through the gate 17 has a suddenly changing basic rod portion 5 whose cross section is uneven from the gate 17. The flow became turbulent, and there was a concern that casting defects such as gas defects due to entrainment of air or gas might occur. Further, when the gate 17 is formed near the center of the basic rod 5, solidification near the gate 17 is delayed, the metal structure in this part becomes coarse, and the tensile strength, proof stress, bending strength, and the like near the center of the rod 8 are reduced. It was expected that the mechanical properties of the connecting member 11 would decrease, and the function as the connecting member 11 would be impaired.
[0036]
In Example 1 and Comparative Examples 1 and 2, the flow-flow solidification simulation and casting of the (JIS) AC4CH composition aluminum alloy were performed by the low-pressure casting method. However, a normal die casting method, a vacuum die casting method, a molten metal forging method, or the like was used. Even when the connecting member is cast by another mold casting method, as described above, the molten metal becomes turbulent or laminar depending on the arrangement and dimensions of the gate, and casting defects occur due to the thickness ratio of the basic rod portion. It was expected that there would be or not.
[0037]
【The invention's effect】
As described in detail above, according to the connecting member of the present invention, an annular or U-shaped load applying portion located at both ends and a rod portion connecting the load applying portion are formed integrally with a connecting member. Reduces the entrapment of air and gas in the part where the cross section changes suddenly, prevents the occurrence of gas defects etc. in the connecting member after the molten metal solidifies, and also has the tensile strength, proof strength and bending strength near the center of the rod. Mechanical properties, such as hardness.
[Brief description of the drawings]
FIGS. 1A and 1B show a connecting member 1 according to a first embodiment, wherein FIG. 1A is a plan view, FIG. 1B is a side view, FIG. 1C is a cross-sectional view taken along line AA in FIG. FIG. 3B is a schematic view showing a cross section BB, FIG. 4E is a schematic view showing a cross section CC in FIG. 4B, and FIG.
FIG. 2 shows (a) H-shape, (b) I-shape, (c) T-shape, (d) U-shape, (e) cross-shape, and (f) O in cross section of the basic rod portion. It is a figure which shows a character shape and thickness T1, T2.
3A and 3B show a connecting member 1 according to a second embodiment, in which FIG. 3A is a plan view, FIG. 3B is a side view, and FIG. 3C is a cross section CC in FIG.
FIGS. 4A and 4B show a connecting member 1 according to a third embodiment, in which FIG. 4A is a plan view, FIG. 4B is a side view, and FIG. 4C is a cross section CC in FIG.
5A and 5B are connecting members 11 of Comparative Example 2, wherein FIG. 5A is a plan view and FIG. 5B is a side view.
FIG. 6A is a plan view of a model of a mold 9 in which a cavity other than a connecting member 1 is formed, and FIG. 6B is a flow diagram of a molten metal flow in a portion A of FIG. And (c) is a schematic diagram of the flow of hot water in the portion B of (a) (near the gate 17 of Comparative Example 2).
FIG. 7 is a diagram showing a result of examining a state of occurrence of a casting defect near the center of a rod portion 8 by a molten metal solidification simulation.
8 (a) is a plan view, FIG. 8 (b) is a side view, and FIG. 8 (c) is a schematic view showing the flow of molten metal at section EE in FIG. 8 (b) during casting. It is.
9A and 9B show another example of a conventional connection member 31. FIG. 9A is a plan view, and FIG. 9B is a view showing a cross section AA in FIG. 9A.
FIG. 10 is a perspective view of a connection member 41 according to still another conventional example.
[Explanation of symbols]
1, 11, 21, 31, 41: connecting member (casting connecting member)
2, 3, 22, 23, 32, 33, 42, 43: load applying parts 4, 6, 44, 46: connecting rod part 61: gate attaching part 62: gate projecting part 6a facing the gate attaching part, 6b, 6c, 6d: recess 5: basic rod 45: central part 7, 17, 27: gate 8, 28, 38, 48: rod 9: mold 9a: gate W1, W4: width W3 of connecting rod : Width of basic rod W2: width of gate H: height L1: length T1, T2: thickness M: molten metal PL: parting line
