JP3834754B2

JP3834754B2 - Sewing machine

Info

Publication number: JP3834754B2
Application number: JP2002166331A
Authority: JP
Inventors: 勝彦岩井; 忠徳井上; 要草積
Original assignee: Yamato Sewing Machine Mfg Co Ltd
Current assignee: Yamato Sewing Machine Mfg Co Ltd
Priority date: 2002-05-01
Filing date: 2002-05-01
Publication date: 2006-10-18
Anticipated expiration: 2022-05-01
Also published as: CN100523349C; JP2003320190A; TWI283275B; TWI283274B; CN1542196B; CN1542196A; CN1690285A; TW200526837A; CN1690285B; TWI289163B; TW200403370A; TW200419027A; CN1455042A

Description

【０００１】
【発明の属する技術分野】
本発明は、主として多本針偏平縫いミシンに適用される針糸繰り装置に関し、詳しくは、ミシンアーム部の左右略中間位置に、該ミシンアーム部の左端部に上下方向に往復運動可能に支持されている針棒の上下往復運動に同期連動して上下方向に往復揺動運動する可動針糸繰り部材が設けられており、糸調子器から繰り出された後、定置針糸道を通過して供給される針糸を可動針糸繰り部材の往復揺動運動により繰り出し制御して針棒の下端に取り付けられている針に向けて下降案内するように構成されているミシンの針糸繰り装置に関するものである。
【０００２】
【従来の技術】
この種のミシンの針糸繰り装置において、縫製生地の厚みや使用する針糸の種類や伸縮性等にかかわらず常に良好な縫い調子を維持するための手段として、従来一般には、可動針糸繰り部材の上下往復揺動運動量（ストローク）又は該運動量及び定置針糸道における糸孔の上下位置の可変機構を設け、この可変機構を縫製生地の厚み等に応じて変更操作することにより、針糸供給経路長さを増減して針糸の繰出し量を制御するように構成されていた。
【０００３】
【発明が解決しようとする課題】
上記従来の針糸繰り装置では、可変機構による針糸繰出し量の調整により、縫製生地の厚みや針糸の種類、伸縮性等の変化にかかわらず常に適正、良好な糸調子、縫い調子を維持することが可能であり、比較的組織が硬く、かつ、伸縮性も低い通常一般的な生地を縫製対象とする場合は、針糸に緩みが発生せず、適正な締まり具合を持つ仕上がりのよい縫製品が得られる。
【０００４】
しかしながら、近年多用化の傾向にあるマイクロファイバー地等のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製対象とする場合に上記した従来の針糸繰り装置をそのまま用いると、緩みがない緊張状態の針糸とルーパ糸で形成される縫い目が針板の爪に巻き付いて爪から抜け出しにくくなり、生地送りに支障を生じて縫製不良を招きやすいだけでなく、仮に、縫い目が爪から抜けたとしても、針が生地を貫通して下死点に至るとき緊張状態にある針糸が生地を下方へ押し込み、かつ、針が下死点から上死点に向けて上昇するとき針糸及びその針糸ループに絡んでいるルーパ糸が針落ち孔部分で生地を引き下げる現象を呈して縫製箇所の生地部分を過剰に強く締め付けることになり、その結果、縫製箇所の生地部分がかまぼこ状に盛り上がり、縫製品質の低下を生じるという問題があった。
【０００５】
すなわち、従来の針糸繰り装置が備えている可変機構は、あくまでも通常一般的な生地を縫製対象とする場合に糸調子、縫い調子を維持することができる範囲で針糸の繰出し量を調整可能としたものに過ぎず、上記マイクロファイバー地等のように組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製対象とする場合に生じる上述のような縫製不良やかまぼこ状の盛り上がりによる縫製品質の低下を回避するに十分な範囲で針糸の繰出し量を制御することができないものであった。
【０００６】
本発明は上記の実情に鑑みてなされたもので、通常一般的な生地を縫製対象とする場合に適正な締まり具合を持たせることができるだけでなく、マイクロファイバー地のように組織が非常に柔らかく、かつ、伸縮性に富んだ素材生地を縫製対象とする場合でも、糸調子を縫いむらの生じない適切なものに保ちつつ生地送りの支障に起因する縫製不良や過剰締付けに起因する縫製品質の低下を生じないように針糸の繰出し量を適正に制御することができるミシンの針糸繰り装置を提供することを目的としている。
【０００７】
【課題を解決するための手段】
上記目的を達成するために、本発明に係るミシンの針糸繰り装置は、左端部に針棒を上下方向に往復運動可能に支持しているミシンアーム部の左右略中間位置の前面部に、針棒の上下往復運動に同期連動して上下方向に往復揺動運動する可動針糸繰り部材が設けられており、この可動針糸繰り部材の先端部及び長手方向の略中間部には、糸調子器から繰り出され、かつ、定置針糸道を通過して供給される針糸を針棒の下端に取り付けられている針に向けて下降案内する第１の針糸繰り孔及び第２の針糸繰り孔が形成されているミシンの針糸繰り装置であって、上記可動針糸繰り部材における第１の針糸繰り孔と第２の針糸繰り孔との間には、これら両針糸繰り孔間に亘る針糸部分を下方へ屈曲させた状態で繰り出し案内する第３の針糸繰り孔を有する針糸案内部が設けられていることを特徴とするものである。
【０００８】
上記構成の本発明によれば、定置針糸道を通過して供給される針糸を可動針糸繰り部材に形成されている第１乃至第３の針糸繰り孔に順次通して針に向けて下降案内させることにより、該可動針糸繰り部材の第１乃至第３の針糸繰り孔に通し保持される針糸部分の全長を長くし、かつ、その長い針糸部分の途中を下向きに屈曲させることで、糸調子器により針糸に付与される繰り出し摩擦抵抗を糸調子にむらの生じない適切な値に保ちつつ、可動針糸繰り部材が上方から下方へ揺動運動する時、糸調子器により付与された摩擦抵抗に抗しての針糸繰出し力を強めて針糸繰出し量を下方ほど漸次大きくすることが可能である。
【０００９】
このように可動針糸繰り部材による針糸の繰出し量が下方ほど漸次大きくなることによって、比較的組織が硬く、かつ、伸縮性の低い通常一般的な生地を縫製対象とする場合、従来と同様に可変機構を介して針糸の繰出し量を調整して用いることにより、針糸に緩みを発生しない適正な締まり具合を持たせて所定どおりの縫製を行えるものでありながら、マイクロファイバー地のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製対象とする場合、針が生地を貫通して下死点に至るときの針糸部分及び針が下死点から上死点に向けて上昇するときの針糸部分を強く緊張させないで少しの緩みを持たせることが可能となり、生地送り時に針板の爪に巻き付いている縫い目を爪からスムーズに抜け出させるとともに、針が下降するときに針糸が生地を下方へ押し込んだり、針が上昇するときにルーパ糸が生地を引き下げたりすることによる過剰締め付けを無くして生地の縫製箇所がかまぼこ状に盛り上がるなどの縫製品質の低下を回避することができる。
【００１０】
上記構成の本発明に係るミシンの針糸繰り装置においては、可動針糸繰り部材に第３の針糸繰り孔を有する針糸案内部を設けることにより、通常一般的な生地からマイクロファイバー地のような柔軟かつ伸縮性に富んだ素材からなる生地まで生地の種類を問わず常に適正な縫製が行えるように針糸の繰出し量制御範囲を大きく確保させているので、これと同等な大きさの繰出し量制御範囲を確保するために、ミシンアーム部の上壁部よりも上方にまで針棒を突出させて、その突出した針捧の上端部に針糸道を設ける必要がなくなる。このことに着目して、請求項２に記載のように、針棒の上下往復運動範囲をミシンアーム部の上壁部分から上方へは突出しない範囲に設定することによって、針棒長さの短縮化及び軽量化により縫製の高速化が容易になるとともに、ミシンアーム部の密閉化により油漏れや塵埃の侵入防止を図ることができる。
【００１１】
なお、針棒の上下運動範囲は、その上端部に針糸道を設ける必要がなくても、その上限をミシンアーム部の上壁部分よりも上方へ突出する範囲に設定してもよい。この場合は、長時間に亘る縫製に伴う摺動熱を針棒の上端部から大気中に放出させるといった放熱機能を発揮させて針棒や針が異常高温になったり、ミシンアーム部内に熱が籠もることによる縫製作業の不具合の発生を防止することができる。
【００１２】
また、上記構成の本発明に係るミシンの針糸繰り装置において、請求項３に記載のように、可動針糸繰り部材における針糸案内部を、それに形成された第３の針糸繰り孔の位置を上下に調節可能とするように上下に位置変更固定自在に構成することが望ましい。この場合は、針糸案内部の上下位置を変更することで、可動針糸繰り部材の上下往復揺動運動に伴う繰出し量の制御範囲を一層大きくすることができる。
【００１３】
また、上記構成の本発明に係るミシンの針糸繰り装置において、請求項４に記載のように、上記可動針糸繰り部材を、針棒が上死点にある時に第１の針糸繰り孔から第２及び第３の針糸繰り孔を経て針棒下端の針に至るまでの間の針糸長さよりも針棒が下死点にある時に第１の針糸繰り孔から第２及び第３の針糸繰り孔を経て針棒下端の針に至るまでの針糸長さが長くなるような上下揺動運動範囲に設定することによって、マイクロファイバー地のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製対象とする場合、可変機構を利用して針糸の繰出し量を調整しなくても、針が下死点に至るときの針糸部分及び針が下死点から上死点に向けて上昇するときの針糸部分を強く緊張させないで緩みを持たせて生地送り時の縫い目の爪からの抜け出しをスムーズにするとともに、針糸およびルーパ糸の過剰締め付けを無くして生地の縫製箇所がかまぼこ状に盛り上がるなどの縫製品質の低下を確実に回避することができる。
【００１４】
さらに、上記構成の本発明に係るミシンの針糸繰り装置において、請求項５に記載のように、上記可動針糸繰り部材先端の第１の針糸繰り孔と針との間に亘る針糸供給経路の途中位置に、該可動針糸繰り部材が下方へ揺動した状態でのみ第１の針糸繰り孔と第３の針糸繰り孔との間に位置する針糸部分を上方への屈曲姿勢に受け止める針糸受けを設けることにより、針が下死点付近にある時の針糸の緩み代を大きくとることが可能となり、マイクロファイバー地のような柔軟かつ伸縮性に富んだ生地を縫製対象とする時の縫製品質の低下を一層確実に防止することができる。
【００１５】
【発明の実施の形態】
以下、本発明の実施の形態を図面にもとづいて説明する。
図１は本発明を適用した３本針偏平縫いミシンの全体正面図、図２は針糸繰り装置の主要部の構成を示す斜視図、図３は図２の要部の拡大正面図である。これら各図において、１はミシンアーム部、２はミシンベッド部で、ミシンアーム部１の左端部には該ミシンアーム部１内に挿通支持されている駆動主軸（図示省略する）に周知のクランク機構を介して連動して上下方向に往復運動可能な針棒３が支持されているとともに、この針棒３に隣接して生地押え機構（周知であるたため、詳細な説明は省略する）が設けられている。
【００１６】
上記針棒３の下端部には針止め４を介して３本の針５が取り付けられているとともに、この針棒３の上下往復運動範囲は該針棒３が上死点にまで上昇運動した状態においてもその上端部がミシンアーム部１の左端部の上壁部分１Ａから上方へ突出しない範囲に設定されている。また、ミシンベッド部２の左端部には針板及びルーパや生地送り機構等の縫いを構成する部品（周知であるため、詳細な説明は省略する）が収容されている。
【００１７】
上記ミシンアーム部１の左右略中間位置の前面部には、上記駆動主軸に連動する針糸繰り軸６の正逆駆動回転により針糸繰り台７を介して針棒３の上下往復運動に同期して該針糸繰り軸６を支点とする上下方向（矢印ｕ−ｄ方向）に往復揺動運動する可動針糸繰り部材８が設けられている。この可動針糸繰り部材８の右側のミシンアーム部１の前面部には、３本の針糸９及び１本のルーパ糸１０に繰り出し摩擦抵抗を付与して糸テンションを個別に調整可能な４つの糸調子器１１から繰り出し案内される４本の糸のうち、３本の針糸９を集合状態で通過させてそれら針糸９に潤滑油を塗布する針糸給油装置１２に一体装備された定置針糸道１３と、この定置針糸道１３を通過後の３本の針糸９を個別に挿通可能で定置針糸道１３に固定連設された糸道取付台１４に長孔１５とねじ１６を介して上下方向（矢印ｕ１−ｄ１方向）に個別に位置変更固定自在に構成された３つの可変針糸道１７が配置されている。
【００１８】
上記可動針糸繰り部材８の先（左）端部及び長手方向の略中間部には、糸調子器１１から繰り出され、かつ、定置針糸道１３及び可変針糸道１７を通過して供給案内される３本の針糸９を、ミシンアーム部１の左端部の上下略中間位置に固定された針糸繰りガイド１８に形成の針糸孔１８ａを通して３本の針５に向けて下降案内する３つづつの第１及び第２の針糸繰り孔８Ａ及び８Ｂがそれぞれ同一高さ位置に並べて形成されているとともに、これら第１の針糸繰り孔８Ａと第２の針糸繰り孔８Ｂとの間の可動針糸繰り部材８部分には、それら両針糸繰り孔８Ａ，８Ｂ間に亘る針糸部分９ａを下方へ向けて左右ほぼ対称のＶ字形状に屈曲させた状態で繰り出し案内する３つの第３の針糸繰り孔８Ｃを上下に位置をずらせて形成した針糸案内部８ａが一体に連設されている。
【００１９】
また、上記可動針糸繰り部材８先端の第１の針糸繰り孔８Ａと針糸繰りガイド１８の針糸孔１８ａとの間に亘る針糸供給経路の途中位置には、図２に示すように、可動針糸繰り部材８が下方（ｄ方向）に揺動した状態でのみ第１の針糸繰り孔８Ａと第３の針糸繰り孔８Ｃとの間に位置する３本の針糸部分９ｂを各別に上方への屈曲姿勢に受け止める３つの糸受け部１９ａを持つ針糸受け１９が針糸繰りガイド１８の上端部分に長孔２０とねじ２１を介して上下に位置変更固定可能に設けられている。この針糸受け１９の３つの糸受け部１９ａは、図４に明示するように、右側（ルーパの針糸ループへの進入が最も早い側）が最も高く、中間、左側の順番に低くなるような段差を付けて形成されている。
【００２０】
上記のような構成の針糸繰り装置を備えた３本針偏平縫いミシンを用いて通常一般的な生地を縫製する場合は、縫製生地の厚みや針糸９９種類、伸縮性等に応じて予め可変針糸道１７を上下方向（ｕ１−ｄ１方向）に位置調整して針糸供給経路の長さを３本の針糸９の繰り出し量が適正になるように、すなわち、針棒３が上死点に上昇している時における針糸供給経路の長さと針棒３が下死点に下降している時における針糸供給経路の長さとがほぼ等しくなるように調整して用いることによって、糸調子器１１による繰出し摩擦抵抗を適正な糸調子が維持されるように調整された後に繰り出し案内される３本の針糸９が、定置針糸道１３→可変針糸道１７→可動針糸繰り部材８の第２の針糸繰り孔８Ｂ→第３の針糸繰り孔８Ｃ→第１の針糸繰り孔８Ａ→針糸繰りガイド１８の針糸孔１８ａの順に通されて３本の針５に向けて下降案内される。
【００２１】
この状態で針棒３及び針５が上下に往復駆動運動されると、これに同期して可動針糸繰り部材８が針糸繰り軸６を中心として上下方向（矢印ｕ−ｄ方向）に往復揺動運動し、糸調子器１１による糸調子及び縫い調子を良好に維持しつつ３本の針糸９に緩みや過剰張力を加えないように針糸９の繰り出し量が適正に制御され、縫製生地の厚み等にかかわらず所定どおりの縫製を行なうことができる。
【００２２】
一方、マイクロファイバー地のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製する場合、定置針糸道１３及び可変針糸道１７を通過して供給される針糸９は可動針糸繰り部材８に形成されている第２の針糸繰り孔８Ｂ、第３の針糸繰り孔８Ｃ及び第１の針糸繰り孔８Ａに順次通され針糸繰りガイド１８の針糸孔１８ａを経て針５に向けて下降案内されるために、該可動針糸繰り部材８に保持されている針糸９部分の全長は長く、かつ、その長い針糸９部分の途中が第３の針糸繰り孔８Ｃを介してほぼＶ字状で下向きに屈曲されているので、糸調子器１１により針糸９に付与される繰出し摩擦抵抗を糸調子に縫いむらの生じない適切な値に保ちつつも、可動針糸繰り部材８が針棒３及び針５の下降移動に連動して図５に示す上昇位置から図６に示す下降位置へ揺動運動する時、▲１▼可変針糸道１７から可動針糸繰り部材８先端の第１の針糸繰り孔８Ａまでの距離Ｌが下方ほど漸次大きくなること、▲２▼第２の針糸繰り孔８Ｂから第３の針糸繰り孔８Ｃへ向かう針糸部分９ａが次第に下向きに姿勢変化して糸調子器１１により付与された繰出し摩擦抵抗に抗しての針糸繰出し力ｆが下方ほど漸次強くなること、並びに、▲３▼可動針糸繰り部材８が図６の下降位置よりも少し上方位置にまで揺動した時点で第３の針糸繰り孔８Ｃと第１の針糸繰り孔８Ａとの間の針糸部分９ｂが針糸受け１９の糸受け部１９ａに受け止められ、この状態から可動針糸繰り部材８が図６の下降位置まで揺動することに伴い受け止められた針糸部分９ｂが上方への屈曲姿勢に変化して糸調子器１１による繰出し摩擦抵抗に抗しての針糸繰出し力ｆがさらに強まることによって、針糸繰出し量が下方ほど漸次大きくなる。
【００２３】
このように可動針糸繰り部材８による針糸９の繰出し量が下方ほど漸次大きくなるために、マイクロファイバー地のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製対象とする場合でも、針５が下死点に至るときの針糸部分及び針５が下死点から上死点に向けて上昇するときの針糸部分を強く緊張させないで少しの緩みを持たせることが可能となり、生地送り時に針板の爪に巻き付いている縫い目を爪からスムーズに抜け出させることができるとともに、針５が生地を上方から貫通するときに針糸が生地を下方へ押し込んだり、針５が上昇するときに針糸およびそれに絡んだルーパ糸が生地を引き下げたりすることによる過剰締め付けを無くして生地の縫製箇所がかまぼこ状に盛り上がるなどの縫製品質の低下を回避することができる。
【００２４】
また、上記可動針糸繰り部材８先端の第１の針糸繰り孔８Ａと針糸繰りガイド１８の針糸孔１８ａとの間に亘る針糸供給経路の途中位置に設けられている針糸受け１９の３つの糸受け部１９ａは、図４に明示するように、右側（ルーパの針糸ループへの進入が最も早い側）が最も高く、中間、左側の順番に低くなるような段差を付けて形成されているので、生地の下方に形成される３本の針糸ループに対するルーパの進入タイミングが左側ループほど遅くても、可動針糸繰り部材８が下降位置に達したときの３本の針糸９の緩み代をほぼ均等に保つことが可能で、マイクロファイバー地等のような柔軟組織生地を縫製する時、縫製箇所がかまぼこ状に盛り上がってしまうなどの縫製品質の低下を確実に防止することができる。
【００２５】
なお、上記実施の形態では、針糸受け１９を設けたものについて説明したが、図７及び図８に示すように、針糸受け１９を設けていない３本針偏平縫いミシンにおいても、既述▲１▼，▲２▼の作用によって、可動針糸繰り部材８が下方へ揺動するほど針糸の繰出し量を漸次大きくして、マイクロファイバー地等のような柔軟組織生地を縫製する時の縫製品質の低下を防止することができるものである。
【００２６】
因みに、本発明者は本発明の提案に際して本願出願人が試作した図９に示すような３本針偏平縫いミシン実機を対象にして、針糸受けが有る場合と針糸受けが無い場合の各々において、針棒が上死点にある時に左右二本の針に供給される針糸長さＡと針棒が下死点にある時に左右二本の針に供給される針糸長さＢとを測定した結果、表１及び表２に示す通りの結果が得られた。なお、各左右二本の針糸長さＡ及びＢは、図９に示すように、針糸供給経路を形成する各針糸道間や針糸繰り孔間等の６つの測定ポイント間寸法▲１▼〜▲６▼を合計した値であり、表１，２中の数値の単位はｍｍである。
【００２７】
【表１】

【００２８】
【表２】

【００２９】
上記の表１及び表２の測定寸法から明らかなように、針糸受けが有る場合で針棒が上死点にある時に左右二本の針に供給される針糸長さＡと針棒が下死点にある時に左右二本の針に供給される針糸長さＢとの比率（Ａ：Ｂ）は、左の針糸で１．００：１．０７、右の針糸で１．００：１．１１であり、また、針糸受けがい場合の比率（Ａ：Ｂ）は、左の針糸で１．００：１．０２、右の針糸で１．００：１．０７であって、いずれの場合も、針棒が下死点にある時の針糸繰出し量が左右共に大きくて緩みがある。したがって、マイクロファイバー地のような柔軟かつ伸縮性に富んだ生地を縫製した場合でも、縫製箇所にかまぼこ状の盛り上がりを生じることなく仕上がり品質の良い縫製品が得られた。特に、針糸受けが有る場合、緩み代を大きくとることが可能となり、一層品質の高い縫製品が得られた。
【００３０】
なお、上記実施の形態では、３本針等の多本針偏平縫いミシンに適用したものについて説明したが、二重環縫いミシンに適用してもよいこと勿論である。
【００３１】
また、可動針糸繰り部材８における第３の針糸繰り孔８Ｃを有する針糸案内部８ａを、図３の矢印ｕ２−ｄ２で示すように、可動針糸繰り部材８に対して上下方向に位置変更固定自在に構成することが好ましい。この場合は、針糸案内部８ａの上下位置変更により第３の針糸繰り孔８Ｃの位置を上下に調節して可動針糸繰り部材の上下往復揺動運動に伴う繰出し量の制御範囲を一層大きくすることができる。
【００３２】
【発明の効果】
以上のように、本発明によれば、可動針糸繰り部材にその先端の第１の針糸繰り孔と長手方向略中間部の第２の針糸繰り孔との間に、それら両繰り孔間に亘る針糸部分を下方へ屈曲させた状態で繰り出し案内する第３の針糸繰り孔を設けることにより、この可動針糸繰り部材の上下往復運動による針糸の繰出し量を下方への揺動時ほど漸次大きくすることができる。これによって、比較的組織が硬く、かつ、伸縮性の低い通常一般的な生地を縫製する場合、針糸に緩みを発生しない適正な締まり具合を持たせて所定どおりの縫製を行えるものでありながら、マイクロファイバー地のように、組織が非常に柔らかく、かつ、伸縮性に富んだ素材からなる生地を縫製する場合でも、糸調子に乱れを発生することなく、針が生地を貫通して下死点に至るときの針糸部分及び針が下死点から上死点に向けて上昇するときの針糸部分を強く緊張させないで少しの緩みを持たせることが可能で、生地送りに伴い針板の爪に巻き付いている縫い目を爪からスムーズに抜け出させることができるとともに、針が生地を上方から貫通するときに針糸が貫通箇所の生地部分を下方へ押し込んだり、針が下降するときに針糸およびそれに絡んだルーパ糸が生地を引き下げたりすることによる過剰締め付けを無くして生地の縫製箇所がかまぼこ状に盛り上がることを防ぎ縫製品質を高めることができる。したがって、本発明は、従来より用いられてきた通常一般的な生地からマイクロファイバー地のように非常に柔らかくかつ伸縮性に富んだ素材からなる生地までの広い範囲の生地に対して常に品質的に良好な縫製品が得られるという顕著な効果を奏する。
【００３３】
特に、請求項２に記載のような構成を採用する場合は、針棒長さの短縮化及び軽量化により縫製の高速化が容易になるとともに、ミシンアーム部の密閉化により油漏れや塵埃の侵入防止を図ることができる。
【００３４】
また、請求項３に記載のような構成を採用することによって、針糸案内部の上下位置の変更により可動針糸繰り部材の上下往復揺動運動に伴う繰出し量の制御範囲を一層大きくすることができる。
【００３５】
さらに、請求項５に記載のような針糸受けを設けることによって、針が下死点付近にある時の針糸の緩み代をより大きくとることが可能となり、マイクロファイバー地のような柔軟かつ伸縮性に富んだ生地を縫製対象とする時の縫製品質の低下を一層確実に防止することができる。
【図面の簡単な説明】
【図１】本発明を適用した３本針偏平縫いミシンの全体正面図である。
【図２】同上３本針偏平縫いミシンにおける針糸繰り装置の主要部の構成を示す斜視図である。
【図３】図２の要部の拡大正面図である。
【図４】針糸受けの要部の拡大左側面図である。
【図５】同上３本針偏平縫いミシンで可動針糸繰り部材が上昇位置（上死点）にある状態の正面図である。
【図６】同上３本針偏平縫いミシンで可動針糸繰り部材が下降位置（下死点）にまで揺動した状態の正面図である。
【図７】同上３本針偏平縫いミシンで、針糸受けが無い場合の可動針糸繰り部材が上昇位置（上死点）にある状態の正面図である。
【図８】同上３本針偏平縫いミシンで、針糸受けが無い場合の可動針糸繰り部材が下降位置（下死点）にまで揺動した状態の正面図である。
【図９】本発明の提案に際して本願出願人が試作した偏平縫いミシン実機を対象にして上死点時及び下死点時に左右二本の針に供給される針糸長さを測定するための測定ポイントを説明する要部の正面図である。
【符号の説明】
１ミシンアーム部
１Ａ上壁部分
３針棒
５針
８可動針糸繰り部材
８ａ針糸案内部
８Ａ第１の針糸繰り孔
８Ｂ第２の針糸繰り孔
８Ｃ第３の針糸繰り孔
９針糸
９ａ屈曲針糸部分
９ｂ針糸受けに受け止められる針糸部分
１１糸調子器
１３定置針糸道
１９針糸受け
１９ａ糸受け部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a needle thread reel that is mainly applied to a multi-needle flat stitch sewing machine. More specifically, the present invention is supported at a substantially intermediate position on the left and right sides of the sewing machine arm portion so as to be reciprocally movable in the vertical direction. A movable needle thread reeling member that swings back and forth in synchronism with the vertical reciprocating motion of the needle bar is provided and is fed through the stationary needle thread path after being fed out from the thread tensioner. The present invention relates to a needle thread reeling device for a sewing machine that is configured so that the needle thread is controlled by a reciprocating swinging motion of a movable needle thread reeling member and guided downward toward a needle attached to the lower end of a needle bar.
[0002]
[Prior art]
In this type of needle thread feeding device of a sewing machine, as a means for maintaining a good sewing tone at all times regardless of the thickness of the sewing fabric, the type of needle thread used, elasticity, etc. By providing a variable mechanism for the vertical reciprocating swinging momentum (stroke) or the amount of movement and the vertical position of the thread hole in the stationary needle thread path, and changing the variable mechanism according to the thickness of the sewing fabric, the needle thread supply path The length is increased or decreased to control the feeding amount of the needle thread.
[0003]
[Problems to be solved by the invention]
In the above conventional needle thread feeding device, by adjusting the needle thread feeding amount by the variable mechanism, the proper and good thread tension and sewing tension are always maintained regardless of changes in the thickness of the sewing fabric, the type of needle thread, the stretchability, etc. When sewing a general fabric that has a relatively hard structure and low elasticity, the needle thread does not loosen and has a good finish with an appropriate tightening degree. Goods are obtained.
[0004]
However, the conventional needle reeling device as described above is used as it is when sewing a fabric made of a material having a very soft structure and rich elasticity, such as a microfiber fabric, which has been increasingly used in recent years. If used, the seam formed by the tensioned needle thread and looper thread that will not loosen will wrap around the nail of the needle plate, making it difficult to come out of the nail, causing trouble in feeding the fabric and causing poor sewing. Even if the seam comes off the nail, when the needle penetrates the fabric and reaches the bottom dead center, the needle thread in tension pushes the fabric downward, and the needle moves from the bottom dead center toward the top dead center. will be tightened excessively strong dough portion of the sewing portion looper thread at stake the needle thread and the needle thread loops when the rise presents a phenomenon of lowering pull the fabric in needle hole portion, so that the sewing portion Living Portion raised in semicylindrical shape, there is a problem that results in a reduction in sewing quality.
[0005]
That is, the variable mechanism is conventional needle thread take-up device comprises the last thread tension when the normal sewing object general fabric, and can adjust the extension amount of the needle thread in a range capable of maintaining the sewing condition However, the above-mentioned poor sewing and kamaboko-like swell that occurs when the fabric is made of a material that is extremely soft and stretchable, such as the above-mentioned microfiber fabric, etc. Thus, the needle thread feed amount could not be controlled within a range sufficient to avoid the deterioration of the quality of the sewn product.
[0006]
The present invention has been made in view of the above circumstances, and not only can a proper tightening condition be obtained when a general fabric is to be sewn, but also the tissue is very soft like a microfiber fabric. In addition, even when a material material rich in stretchability is to be sewn, the quality of the sewn product due to poor sewing or excessive tightening due to trouble in the fabric feed can be maintained while keeping the thread tension appropriate. An object of the present invention is to provide a needle thread feeding device for a sewing machine that can appropriately control the needle thread feeding amount so as not to cause a drop.
[0007]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the needle-feeding device for a sewing machine according to the present invention has a needle on the front end portion of the sewing machine arm portion that supports the needle bar at the left end so that the needle bar can be reciprocated in the vertical direction. A movable needle thread reeling member that reciprocally swings in the vertical direction in synchronization with the vertical reciprocating motion of the rod is provided. A tip of the movable needle thread reeling member and a substantially intermediate portion in the longitudinal direction are provided with a thread tensioner. A first needle thread reel hole and a second needle thread reel hole are formed for guiding the needle thread fed through the stationary needle thread path downwardly toward the needle attached to the lower end of the needle bar. The sewing needle threading device of the sewing machine, wherein a portion of the needle thread spanning between the first needle thread reeling hole and the second needle thread reeling hole is located below the first needle thread reeling hole in the movable needle thread reeling member. 3rd needle thread reeling hole for feeding and guiding in a bent state It is characterized in that the needle thread guide portion having is provided.
[0008]
According to the present invention having the above-described configuration, the needle thread supplied through the stationary needle thread path is sequentially passed through the first to third needle thread reel holes formed in the movable needle thread reel member and is lowered toward the needle. By guiding, the overall length of the needle thread portion held through the first to third needle thread reel holes of the movable needle thread reel member is lengthened, and the middle of the long needle thread portion is bent downward. When the movable needle thread reeling member swings from above to below while maintaining the appropriate frictional resistance applied to the needle thread by the thread tensioner, it is applied by the thread tensioner. It is possible to increase the needle thread feeding force against the frictional resistance and gradually increase the needle thread feeding amount downward.
[0009]
In this way, when the amount of needle thread fed by the movable needle thread reeling member gradually increases toward the bottom, when a normal general fabric having a relatively hard tissue and low stretchability is to be sewn, as in the conventional case. By adjusting the feed amount of the needle thread through a variable mechanism, the needle thread can be sewn as specified with a proper tightening condition that does not cause looseness, but like a microfiber ground When the fabric is made of a material that is extremely soft and stretchable, the needle thread part and the needle are above the bottom dead center when the needle penetrates the fabric and reaches the bottom dead center . is not strongly tense the needle thread portion at the time of rise toward the dead center it becomes possible to have a little bit of slack, along with the to get out to smooth the seam that is wrapped around the claw of the throat plate at the time of the fabric feed from the nail, There or push the needle thread the dough when descending downwards, sewing portion of the fabric looper thread is eliminated excessive tightening caused by or pull the fabric when the needle rises in the sewing quality such as swollen to semi-cylindrical A decrease can be avoided.
[0010]
In the needle threading device for a sewing machine according to the present invention having the above-described configuration, the movable needle thread reeling member is provided with a needle thread guiding portion having a third needle thread reeling hole, so that a soft cloth such as a microfiber fabric is usually used. In addition, the needle thread feed amount control range is kept large so that proper sewing can be performed at all times, regardless of the type of fabric, including stretchable materials. In order to secure the range, it is not necessary to make the needle bar protrude above the upper wall of the sewing machine arm and to provide a needle thread path at the upper end of the protruding needle. Focusing on this, as described in claim 2, the needle bar length is shortened by setting the vertical reciprocating motion range of the needle bar to a range that does not protrude upward from the upper wall portion of the sewing machine arm portion. The sewing speed and weight can be easily increased, and the sealing of the sewing machine arm portion can prevent oil leakage and dust entry.
[0011]
Note that the upper and lower movement range of the needle bar may be set such that the upper end of the needle bar protrudes upward from the upper wall portion of the sewing machine arm portion, even though it is not necessary to provide a needle thread path at the upper end portion. In this case, the needle bar and the needle become abnormally hot due to the heat dissipation function that releases the sliding heat associated with sewing for a long time to the atmosphere from the upper end of the needle bar, or heat is generated in the sewing machine arm. Occurrence of problems in sewing work due to wrinkling can be prevented.
[0012]
Further, in the needle thread take-up device for a sewing machine according to the present invention having the above-described configuration, as described in claim 3, the needle thread guide portion of the movable needle thread take-up member is moved up and down at the position of the third needle thread take-up hole formed therein. It is desirable that the position can be changed and fixed up and down so as to be adjustable. In this case, by changing the vertical position of the needle thread guide portion, it is possible to further increase the control range of the feed amount accompanying the vertical reciprocating swinging motion of the movable needle thread reel member.
[0013]
Further, in the needle thread take-up device for a sewing machine according to the present invention having the above-described configuration, as described in claim 4, when the needle bar is at the top dead center, the movable needle thread take-up member is moved from the first needle thread take-up hole to the second needle take-up hole. When the needle bar is at the bottom dead center, the second and third needle thread reels when the needle bar is at the bottom dead center than the length of the needle thread between the first needle thread reel hole and the needle at the lower end of the needle bar. By setting the vertical rocking movement range so that the needle thread length from the needle bar to the needle at the lower end of the needle bar becomes longer, the structure is very soft and rich in elasticity like a microfiber ground. it case of the sewing object dough made from the material, without using the variable mechanism to adjust the feed amount of the needle thread, the upper needle thread portion and the needle when the needle reaches the bottom dead center from the bottom dead center feed dough to have a slack not let tension strongly needle thread portion at the time of rise toward the top dead center The exit from the nail seam while smoothly, the sewing portion of the fabric by removing the needle thread and looper thread excessive tightening can be prevented reliably decrease in sewing quality such as swollen to semi-cylindrical.
[0014]
Furthermore, in the needle thread feeding device of the sewing machine according to the present invention having the above-described configuration, as described in claim 5, a needle thread supply path extending between the first needle thread reeling hole at the tip of the movable needle thread reeling member and the needle is provided. The needle thread that receives the needle thread portion positioned between the first needle thread reel hole and the third needle thread reel hole in an upwardly bent position only in a state where the movable needle thread reel member swings downward at an intermediate position. By providing a support, it is possible to increase the allowance for loosening of the needle thread when the needle is near the bottom dead center, and when sewing a flexible and stretchable fabric such as a microfiber fabric. The deterioration of the quality of the sewing product can be prevented more reliably.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an overall front view of a three-needle flat stitch sewing machine to which the present invention is applied, FIG. 2 is a perspective view showing the configuration of the main part of a needle thread reel, and FIG. 3 is an enlarged front view of the main part of FIG. In each of these drawings, 1 is a sewing arm portion, 2 is a sewing bed portion, and a crank that is well known for a drive main shaft (not shown) inserted and supported in the sewing arm portion 1 at the left end portion of the sewing arm portion 1. A needle bar 3 that can be reciprocated in the vertical direction in conjunction with the mechanism is supported, and a cloth presser mechanism (known in detail and will not be described in detail) is provided adjacent to the needle bar 3. It has been.
[0016]
Three needles 5 are attached to the lower end portion of the needle bar 3 via a needle stopper 4, and the needle bar 3 moves up and down to the top dead center in the range of the vertical reciprocation of the needle bar 3. Even in the state, the upper end portion is set in a range that does not protrude upward from the upper wall portion 1A of the left end portion of the sewing machine arm portion 1. In addition, the left end portion of the sewing machine bed portion 2 accommodates parts constituting stitches such as a needle plate, a looper, and a fabric feed mechanism (which are well known and will not be described in detail).
[0017]
The front surface portion of the sewing machine arm 1 at a substantially intermediate position on the left and right is synchronized with the vertical reciprocation of the needle bar 3 via the needle thread feeding base 7 by the forward / reverse drive rotation of the needle thread reeling shaft 6 interlocked with the driving main shaft. A movable needle thread reeling member 8 that reciprocally swings in the vertical direction (arrow ud direction) with the needle thread reel shaft 6 as a fulcrum is provided. The front portion of the sewing machine arm portion 1 on the right side of the movable needle yarn feeding member 8 has four needle yarns 9 and one looper yarn 10 that are fed to each other to give a frictional resistance and can individually adjust the yarn tension. Of the four yarns fed out and guided from the thread tensioner 11, three needle yarns 9 are passed in a gathered state, and the needle yarn oil supply device 12 that is provided integrally with the needle yarn oil supply device 12 that applies lubricating oil to the needle yarns 9 is installed. A long hole 15 and a screw are provided in a needle thread path 13 and a thread path mounting base 14 fixedly connected to the stationary needle thread path 13 through which the three needle threads 9 after passing through the stationary needle thread path 13 can be individually inserted. Three variable needle thread paths 17 configured to be individually position-changeable and fixed in the vertical direction (arrow u1-d1 direction) via 16 are arranged.
[0018]
At the tip (left) end of the movable needle thread take-up member 8 and the substantially middle part in the longitudinal direction, the feed guide is fed from the thread tensioner 11 and passes through the stationary needle thread path 13 and the variable needle thread path 17. The three needle threads 9 to be guided are lowered and guided toward the three needles 5 through the needle thread holes 18a formed in the needle thread feed guide 18 fixed at a substantially upper and lower intermediate position of the left end portion of the sewing machine arm portion 3. The first and second

needle thread reels

8A and 8B are formed side by side at the same height, and the movable needle between the first needle thread reel 8A and the second needle thread reel 8B is formed. In the yarn reeling member 8 portion, three third needle thread reels for feeding and guiding the needle yarn portion 9a extending between the two needle

yarn reeling holes

8A and 8B downward and bent in a substantially symmetrical V-shape. Needle thread guide formed by shifting the hole 8C vertically a is integrally connected to.
[0019]
Further, as shown in FIG. 2, the movable needle yarn feeding member 8 is movable in the middle of the needle yarn supply path extending between the first needle yarn feeding hole 8A at the tip of the movable needle yarn feeding member 8 and the needle yarn hole 18a of the needle yarn feeding guide 18. The three needle thread portions 9b positioned between the first needle thread reel hole 8A and the third needle thread reel hole 8C are moved upward only in a state where the needle thread reel member 8 swings downward (d direction). A needle thread receiver 19 having three thread receivers 19a to be received in this bending posture is provided at the upper end portion of the needle thread take-up guide 18 so as to be vertically changeable through a long hole 20 and a screw 21. As clearly shown in FIG. 4, the three thread receivers 19a of the needle thread receiver 19 are highest on the right side (the side where the looper enters the needle thread loop is the earliest), and lower in order of the middle and left sides. It is formed with various steps.
[0020]
When sewing a general fabric using a three-needle flat stitch sewing machine equipped with a needle threading device having the above-described configuration, it is variable in advance according to the thickness of the sewing fabric, 99 types of needle thread, stretchability, etc. The needle thread path 17 is adjusted in the vertical direction (u1-d1 direction) to adjust the length of the needle thread supply path so that the feeding amount of the three needle threads 9 is appropriate, that is, the needle bar 3 is dead. By adjusting and using so that the length of the needle thread supply path when it is raised to the point and the length of the needle thread supply path when the needle bar 3 is lowered to the bottom dead center are used, the thread The three needle threads 9 which are fed and guided after adjusting the feeding frictional resistance by the tensioner 11 so as to maintain an appropriate thread tension are fixed needle thread path 13 → variable needle thread path 17 → movable needle thread reeling member. 8 second needle thread reel 8B → third needle thread reel 8C → first needle thread reel Hole 8A → needle thread take-up is passed through in the order of the needle thread holes 18a of the guide 18 is lowered guided toward the three needles 5.
[0021]
When the needle bar 3 and the needle 5 are reciprocated up and down in this state, the movable needle thread reeling member 8 is reciprocally swung in the vertical direction (arrow ud direction) around the needle thread reeling shaft 6 in synchronism with this. The amount of feeding of the needle thread 9 is appropriately controlled so as not to loosen or apply excessive tension to the three needle threads 9 while moving and maintaining good thread tension and sewing tension by the thread tensioner 11, Regardless of the thickness, sewing can be performed as specified.
[0022]
On the other hand, when sewing a cloth made of a material having a very soft structure and abundant elasticity such as a microfiber ground, the needle supplied through the stationary needle thread path 13 and the variable needle thread path 17 is supplied. The thread 9 is sequentially passed through the second needle thread reel hole 8B, the third needle thread reel hole 8C, and the first needle thread reel hole 8A formed in the movable needle thread reel member 8, and passes through the needle thread hole 18a of the needle thread reel guide 18. After that, the needle thread 9 held by the movable needle thread take-up member 8 is guided to descend toward the needle 5 so that the entire length of the needle thread 9 is long, and the middle part of the long needle thread 9 is the third needle thread take-up hole. Since it is bent substantially downward in a V shape via 8C, it is movable while maintaining the feeding friction resistance applied to the needle thread 9 by the thread tensioner 11 at an appropriate value that does not cause unevenness in the thread tension. The needle thread reeling member 8 is interlocked with the downward movement of the needle bar 3 and the needle 5. When swinging from the ascending position shown in FIG. 5 to the descending position shown in FIG. 6, the distance L from the variable needle thread path 17 to the first needle thread reeling hole 8A at the tip of the movable needle thread reeling member 8 decreases downward. (2) The needle thread portion 9a heading from the second needle thread reel hole 8B to the third needle thread reel hole 8C gradually changes its posture downward and resists the drag friction applied by the thread tensioner 11. The third needle thread feeding hole when the needle thread feeding force f gradually increases in the lower direction and (3) when the movable needle thread feeding member 8 swings to a position slightly above the lowered position in FIG. The needle thread portion 9b between 8C and the first needle thread reel hole 8A is received by the thread receiver 19a of the needle thread receiver 19, and the movable needle thread reel member 8 swings from this state to the lowered position in FIG. The needle thread portion 9b received along with the bent shape upward Needle thread unwinding force f of against the feeding frictional resistance due to the thread tension regulator 11 to change by further intensified, the needle thread feeding amount becomes gradually larger as downward.
[0023]
In this way, the amount of needle thread 9 fed by the movable needle thread reeling member 8 gradually increases as it goes downward, so that a fabric made of a material that is extremely soft in structure and rich in elasticity, such as a microfiber ground, is sewn. even when the target, have a little slack without tensing strongly needle thread portion when the needle thread portion and the needle 5 rises toward the top dead center from the bottom dead center of the needle 5 reaches the bottom dead center The seam wound around the nail of the throat plate can be smoothly pulled out from the nail when the fabric is fed, and the needle thread pushes the fabric downward when the needle 5 penetrates the fabric from above. , decreased needle thread and sewn portions of dough without an excessive clamping by the looper thread tangled in it or pull the fabric sewing quality such as swollen to semi-cylindrical when the needle 5 is raised It can be avoided.
[0024]
Further, 3 of the needle thread receiver 19 provided in the middle of the needle thread supply path extending between the first needle thread reel hole 8A at the tip of the movable needle thread reel member 8 and the needle thread hole 18a of the needle thread reel guide 18 is provided. As clearly shown in FIG. 4, the two thread receiving portions 19 a are formed with steps that are the highest on the right side (the side on which the looper enters the needle thread loop is the fastest), and lower in the middle and left order. Therefore, even if the timing of the looper to the three needle thread loops formed below the fabric is slower as the left loop, the three needle threads 9 when the movable needle thread reeling member 8 reaches the lowered position are displayed. The looseness allowance can be kept almost even, and when sewing soft tissue fabrics such as microfiber fabrics, it is possible to reliably prevent deterioration of the quality of the sewing product, such as the sewn portion swells up in a kamaboko shape. .
[0025]
In the above embodiment, the needle thread receiver 19 is provided. However, as shown in FIGS. 7 and 8, the three-needle flat stitch sewing machine not provided with the needle thread receiver 19 is already described. Sewing at the time of sewing a soft tissue fabric such as a microfiber fabric by gradually increasing the needle thread feeding amount as the movable needle thread reeling member 8 swings downward by the action of (1) and (2). It is possible to prevent deterioration in quality.
[0026]
Incidentally, the present inventor, for the three-needle flat stitch sewing machine as shown in FIG. 9 manufactured by the applicant of the present invention in the proposal of the present invention, has a needle thread receiver and a needle thread receiver , respectively. The needle thread length A supplied to the two left and right needles when the needle bar is at the top dead center and the needle thread length B supplied to the two left and right needles when the needle bar is at the bottom dead center; As a result, the results as shown in Table 1 and Table 2 were obtained. The two left and right needle thread lengths A and B are, as shown in FIG. 9, the dimension between the six measurement points ▲ 1 between the needle thread paths forming the needle thread supply path and between the needle thread reeling holes. The value is the sum of ▼ to ⑥, and the unit of numerical values in Tables 1 and 2 is mm.
[0027]
[Table 1]

[0028]
[Table 2]

[0029]
As is apparent from the measurement dimensions in Tables 1 and 2 above, when there is a needle thread receiver and the needle bar is at top dead center, the needle thread length A and the needle bar supplied to the two left and right needles are The ratio (A: B) of the needle thread length B supplied to the two left and right needles at the bottom dead center is 1.00: 1.07 for the left needle thread and 1. 00: 1.11, and the ratio (A: B) when the needle thread is received is 1.00: 1.02 for the left needle thread and 1.00: 1.07 for the right needle thread. In either case, the needle thread feed amount when the needle bar is at the bottom dead center is large on both the left and right sides and is loose. Therefore, even when a flexible and stretchable fabric such as a microfiber fabric is sewn, a sewn product with a good finishing quality can be obtained without causing a kamaboko-like swell at the sewing location. In particular, when there is a needle thread receiver, it is possible to increase the allowance for loosening , and a sewn product with higher quality is obtained.
[0030]
In the above-described embodiment, the description has been given of the case where the present invention is applied to a multi-needle flat stitch sewing machine such as a three-needle, but it is needless to say that the present invention may be applied to a double chain stitch sewing machine.
[0031]
Further, the position of the needle thread guide portion 8a having the third needle thread reel hole 8C in the movable needle thread reel member 8 is fixed to the movable needle thread reel member 8 in the vertical direction as indicated by the arrow u2-d2 in FIG. It is preferable to configure freely. In this case, by changing the vertical position of the needle thread guide portion 8a, the position of the third needle thread reeling hole 8C is adjusted up and down to further increase the control range of the feed amount associated with the reciprocating rocking motion of the movable needle thread reeling member. be able to.
[0032]
【The invention's effect】
As described above, according to the present invention, the movable needle thread take-up member extends between the first needle thread take-up hole at the front end and the second needle thread take-up hole at the middle portion in the longitudinal direction. By providing a third needle thread feeding hole for feeding and guiding the needle thread portion bent downward, the amount of needle thread fed by the up-and-down reciprocation of the movable needle thread feeding member gradually increases as the needle swings downward. can do. As a result, when sewing an ordinary general fabric having a relatively hard structure and low stretchability, the needle thread can be sewn as prescribed with an appropriate tightening condition that does not cause looseness. Even when sewing a fabric made of a material that is extremely soft and stretchable like a microfiber fabric, the needle penetrates the fabric and dies without causing any disturbance in the thread tension. The needle thread part when reaching the point and the needle thread part when the needle ascends from the bottom dead center toward the top dead center can be given a slight looseness without strongly tensioning the needle plate as the fabric is fed The seam wound around the nail can be smoothly pulled out from the nail, and when the needle penetrates the fabric from above, the needle thread pushes the fabric portion of the penetration portion downward, and the needle when the needle descends Thread and Fabric sewing portions can increase the sewing quality prevents rise in semi-cylindrical looper thread tangled Les is eliminated excessive tightening caused by or lower the dough. Therefore, the present invention is always in quality with respect to a wide range of fabrics ranging from ordinary fabrics that have been used in the past to fabrics made of very soft and stretchable materials such as microfiber fabrics. There is a remarkable effect that a good sewing product can be obtained.
[0033]
In particular, when adopting the configuration as described in claim 2, it is easy to increase the sewing speed by shortening the needle bar length and reducing the weight, and it is possible to prevent oil leakage and dust by sealing the sewing machine arm portion. Intrusion prevention can be achieved.
[0034]
Further, by adopting the configuration as described in claim 3, it is possible to further increase the control range of the feed amount accompanying the up-and-down reciprocating swing motion of the movable needle thread feeding member by changing the vertical position of the needle thread guide portion. it can.
[0035]
Furthermore, by providing the needle thread receiver as described in claim 5, it becomes possible to take a larger allowance for loosening of the needle thread when the needle is near the bottom dead center, It is possible to more reliably prevent deterioration of the quality of the sewing product when a fabric rich in elasticity is used as a sewing object.
[Brief description of the drawings]
FIG. 1 is an overall front view of a three-needle flat stitch sewing machine to which the present invention is applied.
FIG. 2 is a perspective view showing a configuration of a main part of a needle thread reel device in the three-needle flat stitch sewing machine.
FIG. 3 is an enlarged front view of the main part of FIG. 2;
FIG. 4 is an enlarged left side view of a main part of the needle thread receiver.
FIG. 5 is a front view showing a state in which the movable needle thread reeling member is at an ascending position (top dead center) in the three-needle flat stitch sewing machine.
FIG. 6 is a front view showing a state where the movable needle thread reeling member swings to a lowered position (bottom dead center) by the three-needle flat stitch sewing machine.
FIG. 7 is a front view showing a state in which the movable needle thread take-up member is in the raised position (top dead center) when there is no needle thread receiver in the three-needle flat stitch sewing machine.
FIG. 8 is a front view of the three-needle flat stitch sewing machine as described above, in a state where the movable needle thread reel member swings to a lowered position (bottom dead center) when there is no needle thread receiver .
FIG. 9 is a diagram for measuring the length of the needle thread supplied to the two left and right needles at the top dead center and the bottom dead center for a flat stitch sewing machine actually manufactured by the applicant of the present application when proposing the present invention. It is a front view of the principal part explaining a measurement point.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sewing arm part 1A Upper wall part 3 Needle bar 5 Needle 8 Movable needle thread reeling member 8a Needle thread guide part 8A First needle thread reeling hole 8B Second needle thread reeling hole 8C Third needle thread reeling hole 9 Needle thread 9a Bending needle Thread part 9b Needle thread part received by the needle thread receiver 11 Thread tensioner 13 Fixed needle thread path 19 Needle thread receiver 19a Thread receiver

Claims

The needle bar is supported at the left end so that it can be reciprocated in the vertical direction. Needle thread reel member is provided,
The needle thread fed from the thread tensioner and supplied through the stationary needle thread path is attached to the lower end of the needle bar at the distal end portion and the substantially intermediate portion in the longitudinal direction of the movable needle thread reeling member. A needle thread reel device of a sewing machine in which a first needle thread reel hole and a second needle thread reel hole that are guided downward toward the needle are formed,
Between the 1st needle thread reel hole and the 2nd needle thread reel hole in the above-mentioned movable needle thread reel member, the 3rd needle thread which spans between these needle thread reel holes is paid out and guided in the downward direction. A needle thread reeling device for a sewing machine, wherein a needle thread guide portion having a needle thread reel is provided.

The needle thread reeling device for a sewing machine according to claim 1, wherein the reciprocating range of the needle bar is set in a range that does not protrude upward from the upper wall portion of the sewing machine arm portion.

3. The needle thread guide portion of the movable needle thread reel member is configured to be vertically changeable and fixed so that the position of a third needle thread reel hole formed thereon can be adjusted vertically. The needle-feeding device for the sewing machine described.

When the needle bar is at the top dead center, the movable needle thread reel member is longer than the needle thread length from the first needle thread reel hole through the second and third needle thread reel holes to the needle at the lower end of the needle bar. Up-and-down swing movement range in which the needle thread length from the first needle thread reel hole through the second and third needle thread reel holes to the needle at the lower end of the needle bar is long when the needle bar is at the bottom dead center The needle thread reeling device for a sewing machine according to any one of claims 1 to 3, wherein

The first needle thread take-up hole is located in the middle of the needle thread supply path between the first needle thread take-up hole at the tip of the movable needle thread take-up member and the needle only when the movable needle thread take-up member swings downward. The needle thread reel device for a sewing machine according to any one of claims 1 to 4, wherein a needle thread receiver for receiving a needle thread portion positioned between the first needle thread reel hole and the third needle thread reel hole in an upward bending posture is provided.