JP2004180881A

JP2004180881A - Needle feed sewing machine and method for adjusting needle feed of the same

Info

Publication number: JP2004180881A
Application number: JP2002350583A
Authority: JP
Inventors: Tatsuhito Akiyama; 辰仁秋山
Original assignee: Juki Corp
Current assignee: Juki Corp
Priority date: 2002-12-03
Filing date: 2002-12-03
Publication date: 2004-07-02
Anticipated expiration: 2022-12-03
Also published as: JP4036736B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a needle feeding sewing machine which prevents puckering. <P>SOLUTION: The needle feed sewing machine which imparts feeding movement to a needle linked with a feed dog 23 is provided with: a first connection point Q where a first needle feeding arm 27 is connected with one end side of a needle feeding rod 28; a second connection point Q where a second needle feeding arm 26 is connected with the other end side of the needle feeding rod 28; and adjusting members 27, 26 and 28 where the first connection point or the second connection point are adjustably arranged on a circular arc R with the second connection point or the first connection point as a center in starting needle feeding when the needle sticks a needle hole formed at the feed dog to start needle feeding. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
この発明は、針送りミシンに関し、特にその針送り量の調整に関する。
【０００２】
【従来の技術】
ミシンの針を布の送り方向に振って布を送る針送りミシンとして、例えば、図８に示す特許第２６８２３４６号記載のミシンがある。このミシンは、回動軸（支持軸）８０Ａを中心に針棒７を揺動させる針送り機構（針棒揺動台８０、針棒揺動腕８１、針送り軸２４）と、針送りの駆動源である水平送り軸１７と、この水平送り軸１７に固定された針棒揺動クランク８２と、水平送り軸１７の揺動運動を前記針送り軸２４に伝達するリンク部材８３とを備え、上記水平送り軸１７の駆動により針棒７が布の送り方向に揺動するようになっている。
【０００３】
このような針送りミシンにおいて、従来、針送りを行なわずに下送り（送り歯による下送りのみで布を送る）を行なう通常のミシンとして使用するために、上記の針送り運動を停止させる手段が提案されている。例えば、図９に示すように、上記ミシンでは、針送り停止手段としてリンク部材８３の位置をスライド調整可能なスライド機構８４，８５が設けられている。このスライド機構８４，８５は、針棒揺動クランク８２に螺着されたガイドピン８４と、ガイドピン８４に摺動して上下動可能な摺動部材８５から構成される。前記リンク部材８３は摺動部材８５に回動自在に取り付けられている。
【０００４】
そして、図９に示すように、針送り時は、リンク部材８３を上方位置に摺動させてビス８６にて固定することにより通常の針送り量が得られる。一方、下送り時には、リンク部材８３を水平送り軸１７の中心軸線１７Ｌ上までスライド移動させてビス８６にて固定することにより、水平送り軸１７の揺動運動をリンク部材８３並びに針送り機構８０，８１，２４に伝達させないようになっている。この結果、針送り量は零（ゼロ）に変化する。
【特許文献１】
特許第２６８２３４６号公報（第５図）
【０００５】
【発明が解決しようとする課題】
しかしながら、従来の針送りミシンでは、送りを確実に行うために、布に当接する送り歯の表面積を大きくする必要がある。これに伴い、送り歯に針が貫通可能な針孔が設けられている。このような結果、針が布に刺さった状態で布を送るので布ずれは良好となる。しかし、天秤糸締めタイミングでは、常に送り歯が下降しているため、縫目の周辺の支持や押えが不十分となり、縫い縮み、いわゆる、パッカリングが発生しやすいという問題があった。
【０００６】
パッカリングの発生を防止するために、従来の針送りミシンのリンク部材８３を図１０に示す中間位置に移動させて、針送り量を減少させることも考えられる。しかし、この場合針送りミシンの針送り軌跡は、図１１に示すように、針送りと下送りの送り量が一致しているＨ〜Ｉ軌跡から針送りの送り量が減少するＪ〜Ｋ軌跡に変わる。このＪ〜Ｋ軌跡への変更により、針送り量が小さくなるので、針を支点として縫目が送り歯に伸ばされながらおくられるので、パッカリングは防止される。
【０００７】
しかし、針送りの開始時点が遅くなるＪ点に変更されると、針が送り歯に設けた針孔に刺さり針送りを開始するＪ点と、送り歯が針板上部に移動して布送りを開始するＨ点にずれが生じる。このずれにより、針送り開始時点で針落ち不良による針の破損等が発生する可能性がある。このため、従来の針送りミシンでは、針送り量の減少量はごく僅かの減少量に限定され、パッカリングを防止するのに有効な針送り減少量を得ることが出来なかった。
【０００８】
この発明は、上記問題点を解決するためになされたものであって、針の破損等が発生することなく、パッカリングを防止することができる、針送りミシン及びその針送り調整方法に関するものである。
【０００９】
【課題を解決するための手段】
上記課題を解決するために、請求項１記載の発明は、
ミシンベッド内に回動可能に支持され、上軸に連動して回転する上下送り軸（１２）と、
ミシンベッド内に回動可能に支持され、上軸に連動して揺動する水平送り軸（１７）と、
前記上下送り軸と前記水平送り軸に連結されて楕円運動が付与されるとともに、針が貫通可能な針孔が形成された送り歯（２３）と、
ミシンアーム内に前記上軸と平行に配置された支持軸（６０）と、
前記支持軸により布送り方向に沿って揺動自在に支持された針棒揺動台（５）と、
ミシンアーム内に配置され前記針棒揺動台を揺動させる針送り軸（２４）と、
前記針棒揺動台に上下動自在に支持されるとともに、前記上軸に連動して上下動する針棒（７）と、
一端側が前記水平送り軸に固定された第１針送り腕（２７）と、
前記第１針送り腕の他端側にその一端側が連結された針送りロッド（２８）と、
一端側が前記針送りロッドの他端側に連結されるとともに、他端側が前記針送り軸に固定された第２針送り腕（２６）と、を有し、前記送り歯に連動して針に送り運動を付与する針送りミシンにおいて、
前記第１針送り腕と前記針送りロッドの一端側を連結する第１連結点（Ｐ）と、前記第２針送り腕と前記針送りロッドの他端側を連結する第２連結点（Ｑ）と、
前記針が前記送り歯に設けた針孔に刺さり針送りを開始する、針送り開始時に、前記第１連結点または前記第２連結点を中心とする円弧上に、前記第２連結点または前記第１連結点が調節自在に配置される調節部材（２７、２６、２８）を備える構成とした。
【００１０】
請求項１記載の針送りミシンは、針送り開始時の第１連結点Ｐを中心とする円弧上Ｒに、第２連結点Ｑが調節自在に配置される調節部材を備えたり、針送り開始時の第２連結点Ｑを中心とする円弧上に、第１連結点Ｐが調節自在に配置される調節部材を備える構成とした。より具体的には、針送り開始時の第２連結点Ｑを中心とし第１連結点Ｐを通る円弧Ｒ上に、他の連結点（第３連結点Ｓ）を設けることである。第１針送り腕２７には、第１連結点Ｐと第３連結点Ｓを中心とする取付け孔ｓ１、ｐ１が設けられている。また、これら複数の取付け孔同士が連続するような長孔２７ｂを形成したり、円弧Ｒに沿ったＲ状長孔を設けたりする。さらに、偏心ピンを設けて第３連結点を上記円弧に沿う位置に配置することである。
【００１１】
請求項１記載の発明によれば、針が送り歯に設けた針孔に刺さり針送りを開始する針送り開始時と、送り歯が針板上部に移動し布送りを開始する送り開始時とが一致する状態を維持しつつ、針による針送り量を増減させて、パッカリングが生じない縫目を形成することができる。
【００１２】
請求項２記載の発明は、請求項１記載の針送りミシンにおいて、
前記調節部材は、前記送り歯の送り量と針送りの送り量が一致する同一位置と、前記送り歯の送り量に比べて針送り量が減少する減少位置とに、前記第２連結点または前記第１連結点が配置される構成とした。
【００１３】
請求項２記載の発明によれば、送り歯の送り量と針送りの送り量が一致する同一位置を基準にしているので、調整が容易である。
【００１４】
請求項３記載の発明は、請求項１または２記載の針送りミシンにおいて、
前記調節部材は、前記第１針送り腕または前記第２送り腕に形成された長孔である構成とした。
請求項３記載の発明によれば、構造が簡単なので、安価な装置が提供される。
【００１５】
請求項４記載の発明は、送り歯と針が協働して布を送る針送りミシンにおいて、
前記針が前記送り歯に設けた針孔に刺さり針送りを開始する針送り開始時と、前記送り歯が針板上部に移動し布送りを開始する送り開始時とが一致するとともに、
前記「送り歯による布送り量に対して、前記針による針送り量を所定量減少させて、前記針を支点として縫目が前記送り歯に伸ばされながら送られることを特徴とする針送りミシンの針送り調整方法である。
【００１６】
請求項４記載の発明によれば、針曲がりの発生とパッカリングの発生とが防止される。
【００１７】
請求項５記載の発明は、請求項４記載の針送りミシンの針送り調整方法において、
前記針送り量の減少比率は５〜２０％であることを特徴とする針送りミシンの針送り調整方法である。
【００１８】
請求項５記載の発明によれば、より確実に針曲がりの発生とパッカリングの発生とが防止される。
【００１９】
【発明の実施の形態】
この発明の第１実施形態を図１〜図７に基づいて説明する。
この針送りミシンは、ミシンアーム部２内に回動自在に支持された上軸１と、上軸１の左端部に設けられた天秤機構３、針棒上下機構４を備えている。なお「左」、「右」は、オペレータ側から見た方向である。ミシンアーム部２のアゴ部２ａ内には上軸１と平行な揺動軸（支持軸）６０がフレームに固定された軸受６１により回動可能に支持されている。この揺動軸６０の一端側には針棒揺動台５が、他端側にはころ案内台６がそれぞれ固定されている。ころ案内台６にはガイド溝部６ａが形成されている。
【００２０】
針棒揺動台５には針棒７が上下動可能に支持され、ころ案内台６は針棒７の軸心とガイド溝部６ａの中心が一致するように組み付けられている。針棒上下機構４は従来のミシンと同様にクランク機構であり、針棒ロッド８の上端が回動自在に支持されている。針棒ロッド８の下端は針棒抱き９に連結されており、針棒ロッド８が回動すると針棒７が上下動する。
【００２１】
上軸１の右端部には上スプロケット１０が固定されている。ミシンベッド部１１には上下送り軸１２が回動自在に支持され、上下送り軸１２の右端部には下スプロケット１３が固定されている。上下のスプロケット１０、１３の間には、タイミングベルト１９が掛け渡されている。不図示のモータにより、上軸１が回転し、上下のスプロケット１０，１３の間に掛け渡されたタイミングベルト１９を介して上下送り軸１２に上軸１の回転が伝達される。
【００２２】
上下送り軸１２には水平偏心カム１４が固定され、この水平偏心カム１４に水平ロッド１５の一端が遊嵌支持されている。水平ロッド１５の他端は、従来のミシンと同様の水平送り量調節機構１６に連結されている。
【００２３】
ミシンベッド部１１のオペレータ側には水平送り軸１７が回動自在に支持され、この水平送り軸１７には水平送り腕１８の一端が固定され、水平送り腕１８の他端は前記の水平送り量調節機構１６に連結されている。
【００２４】
上軸１の回転が伝達された上下送り軸１２の回転は、水平送り量調節機構１６を介して揺動運動として水平送り腕１８に伝達され、水平送り軸１７が揺動運動を行なう。従って、水平送り軸１７の揺動運動は上軸１の回転と同期している。上下スプロケット１０，１３及びタイミングベルト１９は上下送り軸１２と水平送り軸１７に上軸１の運動を伝達する伝達部材を構成する。
【００２５】
なお、伝達部材はベルトに限らず、リンクを用いて上軸１の運動を上下送り軸１２と水平送り軸１７に伝達してもよい。本実施の形態の場合はタイミングベルト１９により直接駆動される上下送り軸１２は全回転を行ない、水平送り軸１７は揺動運動を行なう。これに代えて、上軸に連動して揺動する２つのリンクを用い、第１のリンクにより上軸１の運動を上下送り軸１２へ、第２のリンクにより上軸１の運動を水平送り軸１７へ、それぞれ個別に伝達する構成でもよい。
【００２６】
上下送り軸１２の左端には送り歯上下運動機構２０が連結され、水平送り軸１７の左端には送り台腕２１が固定されている。送り台２２には送り歯２３が固定されている。この送り台２２は、その一端が送り歯上下運動機構２０に、他端が送り台腕２１にそれぞれ連結されている。そして、送り歯上下運動機構２０の上下運動と水平送り軸１７の揺動運動の合成により、周知の楕円運動が送り歯２３に付与される。図示省略したが、送り歯２３の中央部には、針が貫通可能な針孔が形成されている。
【００２７】
また、ミシンアーム部２には針送り軸２４が回動自在に支持されている。針送り軸２４の左端には連結腕２５がねじ２５ａにより、右端には第２針送り腕２６がねじ２６ａにより、それぞれ固定されている。
【００２８】
水平送り軸１７の右端には第１針送り腕２７が固定されている。この第１針送り腕２７の外周端側には、ロッド段ネジ２８ａを介して針送りロッド２８の一端が回動可能に連結されている。また、針送りロッド２８の他端がロッド段ネジ２６ｂを介して、第２針送り軸腕２６に回動可能に連結されている。
【００２９】
図５は針送り伝達機構３１の詳細図である。針送り伝達機構３１は、水平送り軸１７の揺動運動を、第１針送りロッド２７、針送りロッド２８、第２針送りロッド２６を介して、針送り軸２４に伝達している。そして、第１針送り腕２７と針送りロッド２８の一端側を連結する第１連結点がＰであり、第２針送り腕２６と針送りロッド２８の他端側を連結する第２連結点がＱである。
【００３０】
図５の針送り伝達機構３１の連結状態は、上軸回転角度であれば約１００°である。また、楕円運動が付与される送り歯２３の運動軌跡にあてはめれば、送り歯２３が最も送り方向上流側に位置し、針板上面に接する位置（図６に示すＨ点）である。さらに、針の移動軌跡によれば、針が送り歯２３に設けた針孔に刺さり針送りを開始する時、すなわち、送り方向に針が移動を開始する時である。
【００３１】
そして、針送り開始時の第２連結点Ｑを中心として、針送り開始時の第１連結点Ｐを通る円弧Ｒ上に、第３連結点Ｓを形成する。この第３連結点Ｓは、第１連結点Ｐより第１送り腕中心Ｔに近い位置にあり、伝達する揺動運動量が減少する。そして、連結点Ｐ、Ｓを中心として、針送り開始時の第１針送り腕２７に、連結孔ｐ１、ｓ１が形成される。この連結孔ｐ１、ｓ１には、段ネジ２８ａの先端側ネジ部が通され、このネジ部にナットを装着して、第１針送り腕２７と針送りロッド２８を連結する。
【００３２】
第１実施形態の動作について説明する。
上軸１の回転と同期して水平送り軸１７が揺動すると、水平送り軸１７の揺動運動は第１針送り腕２７、針送りロッド２８、第２針送り腕２６を介して針送り軸２４に伝達される。
【００３３】
針送り軸２４の先端側に固定された連結腕２５と、ころ案内台６は連結リンク２９で連結されている。針送り軸２４の揺動運動は、連結腕２５、連結リンク２９を介してころ案内台６に伝達され、ころ案内台６は揺動軸６０と共に揺動する。従って、揺動軸６０に固定された針棒揺動台５も揺動軸６０を中心として布送り方向Ｆに揺動する。なお、針棒抱き９の右端には、角駒３０が遊嵌されており、この角駒３０の側面はころ案内台６のガイド溝部６ａに係合し、針棒７の回転方向のガタを規制している。以上のように、上軸１が回転すると、針棒７の上下運動と、送り歯２３の動きに同期し、針棒揺動台５が布送り方向（Ｆ方向）に揺動運動を行ない、針送りを行う。
【００３４】
通常、第１針送り腕２７と針送りロッド２８とは、第１連結点Ｐで連結されている。第１連結点Ｐで連結されている場合、針の針送り開始時と送り歯の送り開始時とが一致するとともに、針の針送り量と送り歯の布送り量とはほぼ一致する。
【００３５】
第１針送り腕２７と針送りロッド２８との連結点を、第１連結点Ｐから第３連結点Ｓに変更すると、針の針送り開始時と送り歯の送り開始時は一致するが、送り歯２３の布送り量に対して、針の針送り量は、所定量減少される。
【００３６】
図６は送り歯と針の運動曲線であり、横軸Ｘが布送り方向を、縦軸Ｙが高さ方向を示す。送り歯２３は、針棒上死点の時、図示Ｍ点（上軸回転角０°）に位置する。
【００３７】
最初に送り歯２３の運動曲線について説明する。図示省略のモータが回転すると、送り歯２３には図示反時計方向回りに楕円運動が付与される。そして、送り歯２３は、針板上面に接し且つ送り方向最上流側に位置するＨ点（上軸回転角１００°）から、Ｎ点（上軸回転角１８０°）、布送り方向最下流側Ｉ点（上軸回転角２６０°）を経由してＭ点に戻る。
【００３８】
次に、針送りの運動曲線について説明する。尚、針送りの運動曲線は針が布に刺さり、布を送っている期間を説明する。
【００３９】
まず、第１針送り腕２７と針送りロッド２８が第１連結点Ｐで連結されている場合を説明する。
送り歯２２が針板下面から上昇し、送り方向上昇最上流側のＨ点に位置するとき、針は下降し送り歯の針孔２２ａに刺さる状態となる。その後、送り歯２２の布送りに連動して、針４０も針送り運動を開始し、Ｈ点からＭ点を経由してＩ点を通る運動が付与される。このように、第１連結点Ｐで連結されている場合、針４０が送り歯に設けた針孔２２ａに刺さり針送りを開始する針送り開始時と、送り歯２２が針板上面に移動し布送りを開始する開始時が一致するとともに、送り歯２２の布送り量と針４０の針送り量はほぼ一致する。
【００４０】
次に、第１針送り腕２７と針送りロッド２８が第３連結点Ｓで連結されている場合を説明する。
送り歯２２が針板下面から上昇し、送り方向上昇最上流側のＨ点に位置するとき、針は下降し送り歯の針孔２２ａに刺さる状態となる。その後、送り歯２２の布送りに連動して、針４０も針送り運動を開始し、Ｈ点からＭ点を経由してＬ点を通る運動が付与される。このように、第３連結点Ｓで連結されている場合、針４０が送り歯に設けた針孔２２ａに刺さり針送りを開始する針送り開始時と、送り歯２２が針板上面に移動し布送りを開始する開始時が一致するが、送り歯２２の布送り量に対して、針４０による針送り量は５〜２０％減少する。
【００４１】
次に、第１針送り腕２７と針送りロッド２８の連結点を第１連結点Ｐから、第３連結点Ｓに変更した場合の布送りに関する動作を、図７に基づいて説明する。図７（Ａ）は第１連結点Ｐを使用した場合であり、送り歯の送り量と針送り量が同じに送られる。これに対して、（Ｂ）は第３連結点Ｓを使用した場合であり、針送り量を減少させることによって針を支点として縫目が送り歯に伸ばされながら送られるので、パッカリングが確実に防止される。
また、第３連結点を使用しても、針４０が送り歯に設けた針孔２２ａに刺さり針送りを開始する針送り開始時と、送り歯２２が針板上面に移動し布送りを開始する開始時が一致するので、針が刺さるときに針と送り歯の穴が一致しているため、針折れ等が発生しない。また、送り歯２２の布送り量に対して、針４０による針送り量の減少量を５〜２０％とすると、パッカリングが確実に防止される。
【００４２】
この発明は、上記実施形態に限定されることなく、種々変更可能である。例えば、針送り開始時の第２連結点Ｑを中心として、針送り開始時の第１連結点Ｐを通る円弧Ｒ上に、第３連結点Ｓを形成し、連結点Ｐ、Ｓを中心として、針送り開始時の第１送り腕２７に、連結孔ｐ１、ｓ１が形成されている。これに代えて、連結孔ｐ１、ｓ１が連続するような長孔２７ｂを形成し、この長孔２７ｂの両端部に第１連結孔ｐ１，第２連結孔ｓ１が位置するにすることも容易に考えられる。
【００４３】
また、この長孔が円弧Ｒに沿った長孔で、任意に針送り量を調整することも容易に考えられる。また、針送り開始時の第１連結点Ｐを中心として、針送り開始時の第２連結点Ｑを通る円弧Ｒ上に第３連結点を設けることも容易に考えられる。また、第３連結点や長孔を針送りロッド２８に形成することも容易に考えられる。さらに、偏心ピンを設けて第３連結点を上記円弧に位置にするに配置させることも容易に考えられる。
【００４４】
【発明の効果】
上記のように、請求項１記載の発明によれば、針が送り歯に設けた針孔に刺さり針送りを開始する針送り開始時と、送り歯が針板上部に移動し布送りを開始する送り開始時とが一致する状態を維持しつつ、針による針送り量を増減させて、パッカリングが生じない縫目を形成することができる。
【００４５】
請求項２記載の発明によれば、送り歯の送り量と針送りの送り量が一致する同一位置を基準にしているので、調整が容易である。
【００４６】
請求項３記載の発明によれば、構造が簡単なので、安価な装置が提供される。
【００４７】
請求項４、５記載の発明によれば、パッカリングの発生が防止される。
【図面の簡単な説明】
【図１】本発明による第１実施形態の針送りミシンの面部側を示す斜視図である。
【図２】第１実施形態の主要部を反作業者側から見た斜視図である。
【図３】第１実施形態の主要部を作業者側から見た斜視図である。
【図４】第１実施形態の主要部を作業者側から見た斜視図である。
【図５】第１実施形態の針送り機構の詳細図である。
【図６】送り歯と針の運動曲線を示す図である。
【図７】送り歯の布送りと針の針送りの布への作用を説明する図である。
【図８】従来の針送りミシンの斜視図である。
【図９】針送り量調整機構の詳細図である。
【図１０】針送り量調整機構の詳細図である。
【図１１】従来の針送り量調整機構を使用した場合の送り歯と針の運動曲線を示す図である。
【符号の説明】
１２・・・上下送り軸
１７・・・水平送り軸
２３・・・送り歯
６０・・・支持軸
５・・・・針棒揺動台
２４・・・針送り軸
７・・・・針棒
２７・・・第１針送り腕（調節部材）
２８・・・針送りロッド
２６・・・第２針送り腕（調節部材）
Ｐ・・・・第１連結点
Ｑ・・・・第２連結点
Ｒ・・・・円弧[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a needle feed sewing machine, and more particularly to adjustment of the needle feed amount.
[0002]
[Prior art]
For example, there is a sewing machine described in Japanese Patent No. 2682346 shown in FIG. 8 as a needle feeding sewing machine that feeds the cloth by shaking the sewing machine needle in the cloth feeding direction. The sewing machine includes a needle feed mechanism (needle bar swing base 80, needle bar swing arm 81, needle feed shaft 24) that swings the needle bar 7 around a rotation shaft (support shaft) 80A, and a needle feed mechanism. A horizontal feed shaft 17 as a drive source, a needle bar swinging crank 82 fixed to the horizontal feed shaft 17, and a link member 83 for transmitting the swing motion of the horizontal feed shaft 17 to the needle feed shaft 24 are provided. The needle bar 7 is swung in the cloth feed direction by driving the horizontal feed shaft 17.
[0003]
In such a needle feed sewing machine, conventionally, means for stopping the above-mentioned needle feed movement for use as a normal sewing machine that performs the bottom feed (feeding the cloth only by the bottom feed by the feed dog) without performing the needle feed. Has been proposed. For example, as shown in FIG. 9, the sewing machine is provided with slide mechanisms 84 and 85 that can adjust the position of the link member 83 as a needle feed stop means. The slide mechanisms 84 and 85 include a guide pin 84 screwed to the needle bar swinging crank 82 and a sliding member 85 that slides on the guide pin 84 and can move up and down. The link member 83 is rotatably attached to the sliding member 85.
[0004]
Then, as shown in FIG. 9, at the time of needle feeding, a normal needle feeding amount can be obtained by sliding the link member 83 to the upper position and fixing with the screw 86. On the other hand, at the time of the downward feed, the link member 83 is slid to the center axis 17L of the horizontal feed shaft 17 and fixed by screws 86, whereby the swinging motion of the horizontal feed shaft 17 is linked to the link member 83 and needle feed mechanism 80. , 81 and 24 are not transmitted. As a result, the needle feed amount changes to zero.
[Patent Document 1]
Japanese Patent No. 2682346 (FIG. 5)
[0005]
[Problems to be solved by the invention]
However, in the conventional needle feed sewing machine, it is necessary to increase the surface area of the feed dog in contact with the cloth in order to reliably feed. Accordingly, a needle hole through which the needle can penetrate is provided in the feed dog. As a result, since the cloth is fed in a state where the needle is stuck in the cloth, the cloth displacement is good. However, since the feed dog is always lowered at the balance thread tightening timing, there is a problem that the support and the presser foot around the seam are insufficient, so that sewing shrinkage, so-called puckering is likely to occur.
[0006]
In order to prevent the occurrence of puckering, it is also conceivable to reduce the needle feed amount by moving the link member 83 of the conventional needle feed sewing machine to the intermediate position shown in FIG. However, in this case, as shown in FIG. 11, the needle feed locus of the needle feed sewing machine is a J to K locus in which the feed amount of the needle feed decreases from the H to I locus where the feed amounts of the needle feed and the bottom feed coincide. Changes to. By changing to the J to K locus, the needle feed amount is reduced, so that the seam is extended to the feed dog with the needle as a fulcrum, and puckering is prevented.
[0007]
However, if the needle feed start time is changed to point J, the needle feeds into the needle hole provided in the feed dog and point J starts to feed the needle. Deviation occurs at the H point where the operation starts. Due to this deviation, there is a possibility that a needle breakage or the like due to a needle drop failure may occur at the start of needle feeding. For this reason, in the conventional needle feed sewing machine, the decrease amount of the needle feed amount is limited to a very small decrease amount, and it has not been possible to obtain a needle feed decrease amount effective for preventing puckering.
[0008]
The present invention has been made to solve the above-described problems, and relates to a needle feed sewing machine and a needle feed adjustment method thereof that can prevent puckering without causing needle breakage or the like. is there.
[0009]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1
A vertical feed shaft (12) rotatably supported in the sewing machine bed and rotating in conjunction with the upper shaft;
A horizontal feed shaft (17) rotatably supported in the sewing machine bed and swinging in conjunction with the upper shaft;
A feed dog (23) connected to the vertical feed shaft and the horizontal feed shaft to give an elliptical motion and have a needle hole through which the needle can pass,
A support shaft (60) disposed parallel to the upper shaft in a sewing machine arm;
A needle bar swing base (5) supported by the support shaft so as to swing freely along the cloth feed direction;
A needle feed shaft (24) disposed in a sewing machine arm for swinging the needle bar swing base;
A needle bar (7) that is supported by the needle bar swinging base so as to be movable up and down and that moves up and down in conjunction with the upper shaft;
A first needle feed arm (27) having one end fixed to the horizontal feed shaft;
A needle feed rod (28) having one end connected to the other end of the first needle feed arm;
One end side is connected to the other end side of the needle feed rod, and the other end side has a second needle feed arm (26) fixed to the needle feed shaft. In a needle feed sewing machine that gives feed movement,
A first connection point (P) that connects the first needle feed arm and one end side of the needle feed rod, and a second connection point (Q) that connects the second needle feed arm and the other end side of the needle feed rod. )When,
The needle starts needle feed into a needle hole provided in the feed dog, and when the needle feed is started, the second connection point or the above-described arc on the first connection point or the second connection point It was set as the structure provided with the adjustment member (27, 26, 28) by which a 1st connection point is arrange | positioned freely.
[0010]
The needle feed sewing machine according to claim 1 includes an adjustment member in which the second connection point Q is adjustably disposed on an arc R centered on the first connection point P at the start of needle feed, or the needle feed start is started. On the circular arc centering on the 2nd connection point Q at the time, it was set as the structure provided with the adjustment member by which the 1st connection point P is arrange | positioned freely. More specifically, another connecting point (third connecting point S) is provided on an arc R passing through the first connecting point P with the second connecting point Q at the start of needle feed as the center. The first needle feed arm 27 is provided with mounting holes s1 and p1 centered on the first connection point P and the third connection point S. Further, a long hole 27b is formed such that the plurality of mounting holes are continuous, or an R-shaped long hole along the arc R is provided. Furthermore, an eccentric pin is provided and the third connection point is arranged at a position along the arc.
[0011]
According to the first aspect of the present invention, the needle feed starts when needle feeds into the needle hole provided in the feed dog and the feed dog moves to the upper portion of the needle plate and starts feeding. While maintaining the state in which the two coincide with each other, the needle feed amount by the needle can be increased or decreased to form a stitch that does not cause puckering.
[0012]
The invention according to claim 2 is the needle feed sewing machine according to claim 1,
The adjusting member is located at the same position where the feed amount of the feed dog and the feed amount of the needle feed coincide with each other, and at the reduced position where the needle feed amount decreases compared to the feed amount of the feed dog, The first connection point is arranged.
[0013]
According to the second aspect of the present invention, since the same position where the feed amount of the feed dog matches the feed amount of the needle feed is used as a reference, adjustment is easy.
[0014]
The invention according to claim 3 is the needle feed sewing machine according to claim 1 or 2,
The adjusting member is a long hole formed in the first needle feed arm or the second feed arm.
According to the invention described in claim 3, since the structure is simple, an inexpensive apparatus is provided.
[0015]
In the needle feed sewing machine in which the feed dog and the needle cooperate to send the cloth,
When the needle feed starts when the needle starts to pierce the needle hole provided in the feed dog and the feed start when the feed dog moves to the top of the needle plate and starts cloth feed,
The needle feed sewing machine characterized in that the needle feed amount by the needle is reduced by a predetermined amount with respect to the cloth feed amount by the feed dog, and the stitch is fed while being stretched to the feed dog with the needle as a fulcrum. This is the needle feed adjustment method.
[0016]
According to the fourth aspect of the invention, the occurrence of needle bending and the occurrence of puckering are prevented.
[0017]
The invention according to claim 5 is the needle feed adjusting method for the needle feed sewing machine according to claim 4,
The needle feed adjustment method of the needle feed sewing machine is characterized in that a reduction ratio of the needle feed amount is 5 to 20%.
[0018]
According to the fifth aspect of the present invention, the occurrence of needle bending and puckering can be prevented more reliably.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
1st Embodiment of this invention is described based on FIGS.
The needle feed sewing machine includes an upper shaft 1 that is rotatably supported in the sewing machine arm portion 2, a balance mechanism 3 provided at the left end portion of the upper shaft 1, and a needle bar up-and-down mechanism 4. “Left” and “right” are directions viewed from the operator side. A swing shaft (support shaft) 60 parallel to the upper shaft 1 is rotatably supported by a bearing 61 fixed to the frame in the jaw portion 2a of the sewing machine arm portion 2. The needle bar rocking base 5 is fixed to one end side of the rocking shaft 60, and the roller guide base 6 is fixed to the other end side. The roller guide base 6 is formed with a guide groove 6a.
[0020]
A needle bar 7 is supported on the needle bar swinging base 5 so as to be movable up and down, and the roller guide base 6 is assembled so that the axis of the needle bar 7 and the center of the guide groove 6a coincide. The needle bar up / down mechanism 4 is a crank mechanism like a conventional sewing machine, and the upper end of the needle bar rod 8 is rotatably supported. The lower end of the needle bar rod 8 is connected to a needle bar holder 9, and when the needle bar rod 8 rotates, the needle bar 7 moves up and down.
[0021]
An upper sprocket 10 is fixed to the right end portion of the upper shaft 1. A vertical feed shaft 12 is rotatably supported on the sewing machine bed portion 11, and a lower sprocket 13 is fixed to the right end portion of the vertical feed shaft 12. A timing belt 19 is stretched between the upper and lower sprockets 10 and 13. The upper shaft 1 is rotated by a motor (not shown), and the rotation of the upper shaft 1 is transmitted to the vertical feed shaft 12 via a timing belt 19 stretched between the upper and lower sprockets 10 and 13.
[0022]
A horizontal eccentric cam 14 is fixed to the vertical feed shaft 12, and one end of a horizontal rod 15 is loosely supported by the horizontal eccentric cam 14. The other end of the horizontal rod 15 is connected to a horizontal feed amount adjusting mechanism 16 similar to a conventional sewing machine.
[0023]
A horizontal feed shaft 17 is rotatably supported on the operator side of the sewing machine bed portion 11, and one end of a horizontal feed arm 18 is fixed to the horizontal feed shaft 17, and the other end of the horizontal feed arm 18 is the horizontal feed. It is connected to the quantity adjusting mechanism 16.
[0024]
The rotation of the vertical feed shaft 12 to which the rotation of the upper shaft 1 is transmitted is transmitted to the horizontal feed arm 18 as a swing motion through the horizontal feed amount adjusting mechanism 16, and the horizontal feed shaft 17 performs the swing motion. Therefore, the swinging motion of the horizontal feed shaft 17 is synchronized with the rotation of the upper shaft 1. The upper and lower sprockets 10 and 13 and the timing belt 19 constitute a transmission member that transmits the movement of the upper shaft 1 to the vertical feed shaft 12 and the horizontal feed shaft 17.
[0025]
The transmission member is not limited to a belt, and the movement of the upper shaft 1 may be transmitted to the vertical feed shaft 12 and the horizontal feed shaft 17 using a link. In the case of this embodiment, the vertical feed shaft 12 directly driven by the timing belt 19 performs full rotation, and the horizontal feed shaft 17 performs a swinging motion. Instead, using two links that swing in conjunction with the upper shaft, the first link moves the motion of the upper shaft 1 to the vertical feed shaft 12, and the second link feeds the motion of the upper shaft 1 horizontally. The structure which transmits to the axis | shaft 17 separately may be sufficient.
[0026]
A feed dog vertical motion mechanism 20 is connected to the left end of the vertical feed shaft 12, and a feed base arm 21 is fixed to the left end of the horizontal feed shaft 17. A feed dog 23 is fixed to the feed base 22. The feed base 22 has one end connected to the feed dog vertical motion mechanism 20 and the other end connected to the feed base arm 21. Then, a known elliptical motion is imparted to the feed dog 23 by combining the vertical motion of the feed dog vertical motion mechanism 20 and the swing motion of the horizontal feed shaft 17. Although not shown, a needle hole through which the needle can penetrate is formed at the center of the feed dog 23.
[0027]
Further, a needle feed shaft 24 is rotatably supported on the sewing machine arm portion 2. A connecting arm 25 is fixed to the left end of the needle feed shaft 24 by a screw 25a, and a second needle feed arm 26 is fixed to the right end by a screw 26a.
[0028]
A first needle feed arm 27 is fixed to the right end of the horizontal feed shaft 17. One end of the needle feed rod 28 is rotatably connected to the outer peripheral end side of the first needle feed arm 27 via a rod step screw 28a. The other end of the needle feed rod 28 is rotatably connected to the second needle feed shaft arm 26 via a rod step screw 26b.
[0029]
FIG. 5 is a detailed view of the needle feed transmission mechanism 31. The needle feed transmission mechanism 31 transmits the swing movement of the horizontal feed shaft 17 to the needle feed shaft 24 via the first needle feed rod 27, the needle feed rod 28, and the second needle feed rod 26. A first connection point that connects one end side of the first needle feed arm 27 and the needle feed rod 28 is P, and a second connection point that connects the second needle feed arm 26 and the other end side of the needle feed rod 28. Is Q.
[0030]
The connected state of the needle feed transmission mechanism 31 in FIG. 5 is about 100 ° when the upper shaft is rotated. Further, if applied to the motion trajectory of the feed dog 23 to which the elliptical motion is applied, the feed dog 23 is located at the most upstream side in the feed direction and is in contact with the upper surface of the needle plate (point H shown in FIG. 6). Further, according to the movement trajectory of the needle, the needle is inserted into the needle hole provided in the feed dog 23, and when the needle starts to feed, that is, when the needle starts to move in the feeding direction.
[0031]
Then, a third connection point S is formed on an arc R passing through the first connection point P at the start of needle feed, with the second connection point Q at the start of needle feed as the center. The third connection point S is closer to the first feed arm center T than the first connection point P, and the amount of swinging motion transmitted is reduced. Then, the connection holes p1 and s1 are formed in the first needle feed arm 27 when the needle feed is started with the connection points P and S as the center. Through the connection holes p 1 and s 1, threaded ends of stepped screws 28 a are passed, and nuts are attached to the threaded portions to connect the first needle feed arm 27 and the needle feed rod 28.
[0032]
The operation of the first embodiment will be described.
When the horizontal feed shaft 17 swings in synchronization with the rotation of the upper shaft 1, the swing motion of the horizontal feed shaft 17 moves through the first needle feed arm 27, the needle feed rod 28 and the second needle feed arm 26. It is transmitted to the shaft 24.
[0033]
The connecting arm 25 fixed to the tip end side of the needle feed shaft 24 and the roller guide base 6 are connected by a connecting link 29. The swing motion of the needle feed shaft 24 is transmitted to the roller guide base 6 via the connecting arm 25 and the connecting link 29, and the roller guide base 6 swings together with the swing shaft 60. Accordingly, the needle bar swing base 5 fixed to the swing shaft 60 also swings in the cloth feeding direction F around the swing shaft 60. A square piece 30 is loosely fitted to the right end of the needle bar holder 9, and the side surface of the square piece 30 engages with the guide groove portion 6 a of the roller guide base 6, so that the needle bar 7 rotates in the rotational direction. It is regulated. As described above, when the upper shaft 1 rotates, the needle bar rocking base 5 performs a rocking movement in the cloth feeding direction (F direction) in synchronization with the vertical movement of the needle bar 7 and the movement of the feed dog 23. Perform needle feed.
[0034]
Usually, the first needle feed arm 27 and the needle feed rod 28 are connected at a first connection point P. When connected at the first connecting point P, the needle feed start time of the needle coincides with the feed dog feed start time, and the needle feed amount of the needle and the cloth feed amount of the feed dog substantially coincide.
[0035]
When the connection point between the first needle feed arm 27 and the needle feed rod 28 is changed from the first connection point P to the third connection point S, the needle feed start time and the feed dog feed start time coincide, The needle feed amount of the needle is decreased by a predetermined amount with respect to the cloth feed amount of the feed dog 23.
[0036]
FIG. 6 is a motion curve of the feed dog and the needle, where the horizontal axis X indicates the cloth feed direction and the vertical axis Y indicates the height direction. The feed dog 23 is located at an M point (upper shaft rotation angle 0 °) in the figure when the needle bar is at the top dead center.
[0037]
First, the motion curve of the feed dog 23 will be described. When a motor (not shown) rotates, an elliptical motion is imparted to the feed dog 23 counterclockwise. The feed dog 23 comes in contact with the upper surface of the needle plate and is located at the most upstream side in the feed direction, from the H point (upper shaft rotation angle 100 °) to the N point (upper shaft rotation angle 180 °), the most downstream side in the cloth feed direction. Return to point M via point I (upper axis rotation angle 260 °).
[0038]
Next, a needle feed movement curve will be described. The needle feed movement curve describes the period during which the needle is stuck in the cloth and the cloth is fed.
[0039]
First, a case where the first needle feed arm 27 and the needle feed rod 28 are connected at the first connection point P will be described.
When the feed dog 22 rises from the lower surface of the needle plate and is positioned at the point H on the most upstream side in the feed direction, the needle descends and enters the needle hole 22a of the feed dog. Thereafter, in conjunction with the cloth feed of the feed dog 22, the needle 40 also starts a needle feed movement, and a movement from the H point through the M point to the I point is given. Thus, when connected at the first connecting point P, the needle 40 starts to feed the needle hole 22a provided in the feed dog, and when the needle feed starts, the feed dog 22 moves to the upper surface of the needle plate. The start time for starting the cloth feed coincides, and the cloth feed amount of the feed dog 22 and the needle feed amount of the needle 40 substantially coincide.
[0040]
Next, a case where the first needle feed arm 27 and the needle feed rod 28 are connected at the third connection point S will be described.
When the feed dog 22 rises from the lower surface of the needle plate and is positioned at the point H on the most upstream side in the feed direction, the needle descends and enters the needle hole 22a of the feed dog. Thereafter, in conjunction with the cloth feed of the feed dog 22, the needle 40 also starts a needle feed motion, and a motion passing through the L point from the H point through the M point is given. Thus, when connected at the third connecting point S, when the needle 40 starts to feed the needle hole 22a provided in the feed dog and when the needle feed starts, the feed dog 22 moves to the upper surface of the needle plate. Although the start time of starting the cloth feed coincides, the needle feed amount by the needle 40 is reduced by 5 to 20% with respect to the cloth feed amount of the feed dog 22.
[0041]
Next, an operation relating to cloth feeding when the connection point of the first needle feed arm 27 and the needle feed rod 28 is changed from the first connection point P to the third connection point S will be described with reference to FIG. FIG. 7A shows a case where the first connection point P is used, and the feed amount of the feed dog and the needle feed amount are sent to be the same. On the other hand, (B) shows the case where the third connecting point S is used. By reducing the needle feed amount, the stitch is fed while being stretched to the feed dog by using the needle as a fulcrum. To be prevented.
Even when the third connecting point is used, the needle 40 starts to feed the needle hole 22a provided in the feed dog, and when the needle feed starts, the feed dog 22 moves to the upper surface of the needle plate and starts the cloth feed. Since the start time of the needles coincides, the needle and the feed dog hole coincide when the needle is pierced, so that needle breakage or the like does not occur. Further, when the decrease amount of the needle feed amount by the needle 40 is 5 to 20% with respect to the cloth feed amount of the feed dog 22, puckering is reliably prevented.
[0042]
The present invention is not limited to the above embodiment and can be variously modified. For example, a third connection point S is formed on an arc R passing through the first connection point P at the start of needle feed with the second connection point Q at the start of needle feed as the center, and the connection points P and S are set at the center. The first feed arm 27 at the start of needle feed is formed with connection holes p1 and s1. Instead, it is easy to form a long hole 27b in which the connection holes p1 and s1 are continuous, and the first connection hole p1 and the second connection hole s1 are located at both ends of the long hole 27b. Conceivable.
[0043]
Further, it is easily considered that the long hole is a long hole along the arc R and the needle feed amount is arbitrarily adjusted. It is also easily conceivable to provide a third connection point on the arc R passing through the second connection point Q at the start of needle feed, centering on the first connection point P at the start of needle feed. It is also easily conceivable to form a third connection point or a long hole in the needle feed rod 28. Furthermore, it is easily conceivable to provide an eccentric pin so that the third connecting point is located on the arc.
[0044]
【The invention's effect】
As described above, according to the first aspect of the present invention, the needle feeds into the needle hole provided in the feed dog at the start of needle feed, and the feed dog moves to the upper portion of the needle plate to start the cloth feed. It is possible to form a stitch that does not cause puckering by increasing or decreasing the needle feed amount by the needle while maintaining a state that coincides with the feed start time.
[0045]
According to the second aspect of the present invention, since the same position where the feed amount of the feed dog matches the feed amount of the needle feed is used as a reference, adjustment is easy.
[0046]
According to the invention described in claim 3, since the structure is simple, an inexpensive apparatus is provided.
[0047]
According to the fourth and fifth aspects of the invention, the occurrence of puckering is prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a surface side of a needle feed sewing machine according to a first embodiment of the present invention.
FIG. 2 is a perspective view of the main part of the first embodiment as seen from the side opposite to the worker.
FIG. 3 is a perspective view of the main part of the first embodiment as viewed from the operator side.
FIG. 4 is a perspective view of the main part of the first embodiment as viewed from the operator side.
FIG. 5 is a detailed view of the needle feed mechanism of the first embodiment.
FIG. 6 is a diagram showing a movement curve of a feed dog and a needle.
FIG. 7 is a diagram for explaining the action of the feed dog on the cloth and the needle feed on the cloth.
FIG. 8 is a perspective view of a conventional needle feed sewing machine.
FIG. 9 is a detailed view of a needle feed amount adjusting mechanism.
FIG. 10 is a detailed view of a needle feed amount adjusting mechanism.
FIG. 11 is a diagram showing a movement curve of a feed dog and a needle when a conventional needle feed amount adjusting mechanism is used.
[Explanation of symbols]
12 ... Vertical feed shaft 17 ... Horizontal feed shaft 23 ... Feed dog 60 ... Support shaft 5 ... Needle bar swing base 24 ... Needle feed shaft 7 ... Needle bar 27 ... 1st needle feed arm (adjustment member)
28 ... Needle feed rod 26 ... Second needle feed arm (adjustment member)
P ... First connection point Q ... Second connection point R ... Arc

Claims

A vertical feed shaft that is rotatably supported in the sewing bed and rotates in conjunction with the upper shaft, and a horizontal feed shaft that is rotatably supported in the sewing bed and swings in conjunction with the upper shaft;
Connected to the vertical feed shaft and the horizontal feed shaft to give an elliptical motion, and a feed dog having a needle hole through which the needle can penetrate,
A support shaft disposed parallel to the upper shaft in a sewing machine arm;
A needle bar swing base supported by the support shaft so as to be swingable along the cloth feed direction;
A needle feed shaft which is arranged in a sewing machine arm and swings the needle bar swing base;
A needle bar that is supported by the needle bar swinging base so as to be movable up and down, and that moves up and down in conjunction with the upper shaft;
A first needle feed arm having one end fixed to the horizontal feed shaft;
A needle feed rod having one end connected to the other end of the first needle feed arm;
One end side is connected to the other end side of the needle feed rod, and the other end side has a second needle feed arm fixed to the needle feed shaft, and feeds the needle in conjunction with the feed dog. In the needle feed sewing machine to be applied,
A first connection point that connects the first needle feed arm and one end of the needle feed rod;
A second connection point for connecting the second needle feed arm and the other end of the needle feed rod;
The needle starts needle feed into a needle hole provided in the feed dog, and when the needle feed is started, the second connection point or the above-described arc on the first connection point or the second connection point A needle feed sewing machine comprising an adjustment member in which the first connection point is adjustably disposed.

The needle feed sewing machine according to claim 1,
The adjusting member is located at the same position where the feed amount of the feed dog and the feed amount of the needle feed coincide with each other, and at the reduced position where the needle feed amount decreases compared to the feed amount of the feed dog, A needle feed sewing machine, wherein the first connection point is arranged.

The needle feed sewing machine according to claim 1 or 2,
The needle feed sewing machine, wherein the adjustment member is a long hole formed in the first needle feed arm or the second feed arm.

In the needle feed sewing machine in which the feed dog and the needle cooperate to send the cloth,
When the needle feed starts when the needle starts to pierce the needle hole provided in the feed dog and the feed start when the feed dog moves to the top of the needle plate and starts cloth feed,
The needle of the needle feed sewing machine, wherein the needle feed amount by the needle is decreased by a predetermined amount with respect to the cloth feed amount by the feed dog, and the stitch is fed while being stretched to the feed dog with the needle as a fulcrum. Feed adjustment method.

In the needle feed adjusting method of the needle feed sewing machine according to claim 4,
The needle feed adjusting method for a needle feed sewing machine, wherein the reduction rate of the needle feed amount is 5 to 20%.