JP3867874B2

JP3867874B2 - Sewing machine differential feeder

Info

Publication number: JP3867874B2
Application number: JP18756997A
Authority: JP
Inventors: 信介長坂; 秀高稲垣; 克也渡会
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 1997-06-26
Filing date: 1997-06-26
Publication date: 2007-01-17
Anticipated expiration: 2017-06-26
Also published as: JPH119866A

Description

【０００１】
【発明の属する技術分野】
本発明は、ミシンの差動送り装置に関し、特に、主送り歯部材の送り量に対する差動送り歯部材の送り量の比を無段階的に切換え可能に構成したものに関する。
【０００２】
【従来の技術】
従来、伸縮性のある布（伸縮地）を縫製可能なミシンには、針板上の縫製対象の布を押え足と協働して布送り方向（前後方向）へ送る差動送り歯と主送り歯が、縫針の針落ち点を挟んで前後に配置され、伸縮地を縫製する場合、差動送り歯を主送り歯の送り量より大きな送り量で送り作動させ、主送り歯に対して差動送り歯で伸縮地の伸び量分を予め余分に送り、伸縮地に伸びが生じないようにして布送りする差動送り装置が設けられている。
【０００３】
例えば、特開平５−３１７５５０号公報に記載の差動送り装置においては、主送り歯と副送り歯（差動送り歯）が、前後方向へ移動自在に支持された主送り歯取付け軸と副送り歯取付け軸の先端部に設けられ、主送り駆動機構により主送り歯取付け軸に前後駆動力を伝達し、副送り駆動機構により副送り歯取付け軸に前後駆動力を伝達し、主送り歯と副送り歯を送り作動させるように構成してある。
【０００４】
前記主送り駆動機構は、駆動軸の回転運動を直線運動に変換してその駆動力を主送りスライドロッドに伝達し、主送りスライドロッドを前後へ揺動させることにより主送り歯取付け軸に前後駆動力を伝達する一般的な機構であり、主送りスライドロッドをその長さ方向へスライドさせることで、主送りスライドロッドの揺動量が変化し、主送り歯の送り量を調節できるようになっている。
【０００５】
一方、前記副送り駆動機構は、主送り歯取付け軸の前後移動による駆動力を、複数の駆動伝達部材を介して副送りスライドロッドに伝達し、副送りスライドロッドを前後へ揺動させることで、副送り歯取付軸に前後駆動力を伝達するように構成してある。副送りスライドロッドはその長さ方向へスライド自在に支持され、差動調整レバーを操作し副送りスライドロッドをスライドさせることで、副送りスライドロッドの揺動量が変化し、副送り歯取付け軸の前後移動ストローク、つまり副送り歯の送り量を調節できるように構成してある。
【０００６】
【発明が解決しようとする課題】
前記公報の差動送り装置では、主送り歯取付け軸と副送り歯取付け軸とを設け、これら１対の取付け軸を介して主送り歯と副送り歯を夫々支持する構造であり、しかも、主送り歯取付け軸の前後移動による駆動力を、複数の駆動伝達部材と副送りスライドロッド等を介して、副送り取付け軸に伝達する副送り駆動機構を設けなければならないため、差動送り装置が部品数の多い複雑且つ大型の構造になり、その製作コストも高価になる。
【０００７】
本発明の目的は、主送り歯部材の送り量に対する差動送り歯部材の送り量の比を無段階的に切換え可能であって、簡単且つ小型の構造のミシンの差動送り装置を提供することである。
【０００８】
【課題を解決するための手段】
請求項１のミシンの差動送り装置は、針板上の縫製対象の布を送る主送り歯を備えた主送り歯部材と、前記布を送る差動送り歯を前記主送り歯の前方の位置に備えた差動送り歯部材と、前記主送り歯部材に送り駆動力を伝達する主送り部材と、前記主送り歯部材の送り量に対する差動送り歯部材の送り量の比を無段階的に切換え可能にする為の切換え操作機構とを備えたミシンの差動送り装置において、前記主送り部材に対してその主送り部材の移動方向と交差する方向の一軸線の回りに枢着され、且つその枢着部を挟んでその一側部に前記切換え操作機構の突起状係合部を相対移動可能に係合させる円弧状の係合部を有するリンク部材と、前記差動送り歯部材に固定され、且つその差動送り歯部材を前記主送り歯部材と一体的に上下動させるとともに主送り歯部材に対して布送り方向へ所定ストローク相対移動自在に連結された連結部材とを備え、前記リンク部材における前記枢着部を挟んでその他側部と前記連結部材とを可動連結手段によって直接連結したものである。
【０００９】
主送り部材によって主送り歯部材に送り駆動力が伝達されるとともに、リンク部材を介して差動送り歯部材にも送り駆動力が伝達され、主送り歯部材と差動送り歯部材が送り作動する。伸縮性のない布を縫製する場合には、主送り歯部材の送り量に対する差動送り歯部材の送り量の比を１：１に切換えると、主送り歯と差動送り歯部材は一体的に相等しい送り量で送り作動する。
伸縮性のある布（伸縮地）を縫製する場合、伸縮性の大きな伸縮地には前記送り量の比が大きくなるように、また、伸縮性の小さな伸縮地には前記送り量の比が小さくなるように、伸縮地の伸縮性に応じ前記送り量の比を適正な比に切換えると、その比で以て主送り歯と差動送り歯部材が送り作動し、主送り歯に対して差動送り歯で伸縮地の伸び量分が予め余分に送られ、伸縮地に伸びが生じないように布送りが実行され、縫製の仕上がりが良好になる。
【００１０】
請求項２のミシンの差動送り装置は、請求項１の発明において、前記可動連結手段は、前記リンク部材の前記他側部と前記連結部材との一方に設けられたピンと、他方に設けられ前記ピンを可動自在に係合させる溝状係合部とによって構成したことを特徴とするものである。
【００１１】
主送り部材が前後へ揺動駆動されると、主送り歯に送り駆動力が伝達され主送り歯が送り作動するとともに、主送り部材に対してその主送り部材の移動方向と交差する方向の一軸線の回りに枢着されたリンク部材が、その円弧状の係合部に係合した突起状係合部を中心として揺動し、このリンク部材から可動自在に係合したピン及び溝状係合部を介して差動送り歯部材に送り駆動力が伝達され、差動送り歯部材が送り作動する。その他請求項１と同様の作用を奏する。
【００１２】
【００１３】
【００１４】
【発明の実施の形態】
以下、本発明の実施の形態について図面を参照しつつ説明する。本実施形態は、主に布の縁を縫製する為のロックミシンに本発明を適用した場合の一例である。但し、このロックミシンを操作する操作者を基準とし、手前側を前方、左右方向を左右方向として説明する。
【００１５】
図１〜図５に示すように、ロックミシンＭは、ベッド部８０と、ベッド部８０の右部に立設された脚柱部８１と、脚柱部８１上部から左方へ伸びるアーム部８２を有し、ベッド部８０の左端部分は片持ち状のフリーベッド部８３に構成されている。フリーベッド部８３上面部には針板８４が設けられ、この針板８４に布送り方向に伸長して形成された長孔から突出可能に、送り作動する差動送り歯３と主送り歯１とが前後に配置されている。アーム部８２には、主送り歯１と差動送り歯３との間に縫製対象の布を押さえる押え足８５と、押え足８５を下降位置と上昇位置とに切換える切換えレバー８６が装着され、下降位置に切換えられた押え足８５と協働して、主送り歯１と差動送り歯３により、針板８４上の縫製対象の布が布送り方向（前後方向）へ送られる。
【００１６】
アーム部８２には、下端に１対の縫針８８を装着し且つ針棒上下駆動機構（図示略）により上下動される針棒８７が支持されている。脚柱部８０の後端部には、複数本（例えば４本）の糸立９２と糸案内部材８９が立設され、脚柱部８１の前面部には糸調子調節ツマミ９０が設けられ、脚柱部８１の右側面部には、主送り歯１の送り量を調節する送り量調節ツマミ１０７と、駆動軸１０に連結された回動操作部材９１が設けられ、フリーベッド部８３の前面側には、差動送り装置６のダイヤル部材４０の一部分が突出している。
【００１７】
図４〜図９に示すように、ロックミシンＭの内部には、主送り歯１を備えた主送り歯部材２と、差動送り歯３を備えた差動送り歯部材４と、主送り歯部材２と差動送り歯部材４に前後駆動力を伝達する前後駆動機構５と、主送り歯部材２に対する差動送り歯部材４の布送り量を無段階的に切換え可能な差動送り装置６と、可動刃５５と主送り歯部材２と差動送り歯部材４に上下駆動力を伝達する上下駆動機構７と、差動送り歯３と主送り歯１の高さ位置を夫々微調節可能な高さ位置調節装置（第１調節機構８と第２調節機構９）等が設けられている。
【００１８】
主送り歯部材２は、主送り腕１４（主送り部材）の上端部に左右方向向きのピン部材１６に枢着された取付け部材１７に、第２調節機構９を介して高さ位置調節可能に連結され、差動送り歯部材４は、その後端部において差動送り装置６のスライド機構２０を介して主送り歯部材２に支持され、その前端部において、引張りコイルバネ１８で下方へ付勢されて、揺動伝達部材６０の伝達部６２に摺動自在に支持されている。
【００１９】
前後駆動機構５について説明する。
前後駆動機構５は、ベッド部８０内のミシンモータ（図示略）により回転駆動される駆動軸１０と、駆動軸１０に固着された前後駆動用カム１１と、前後駆動用カム１１に上下方向略中段部が摺接された前後駆動力伝達部材１２と、下端部においてフレームに回転自在に支持された左右方向向きの水平な枢支軸１３に枢支された主送り腕１４とを有し、前後駆動力伝達部材１２の下端部が主送り腕１４のレバー部１４ｂに揺動可能にピン結合されている。
【００２０】
前後駆動力伝達部材１２は駆動軸１０の後側に配設され、一端部をフレームに連結した引張りコイルバネ１５により前斜め上方へ付勢され、前後駆動力伝達部材１２の中段部分前端の摺動面１２ａが前後駆動用カム１１に摺動自在に当接している。主送り腕１４は左右両端部分に１対の屈曲部１４ａを有し、これら屈曲部１４ａの下端部が枢支軸１３に枢支され、右側の屈曲部１４ａの下端部からレバー部１４ｂが前方へ延びている。前記取付け部材１７を枢支するピン部材１６は左右１対の屈曲部１４ａの上端部にスライド不可で且つ揺動可能に架着されている。
【００２１】
前後駆動力伝達部材１２の上端部には送り量調節機構１００の角駒１０１が回転自在に連結され、この角駒１０１はフレームに水平軸心回りに支持された係合部材１０２の係合溝１０２ａに摺動自在に係合している。前後駆動力伝達部材１２が前後駆動用カム１１により前後に駆動されると、角駒１０１が係合溝１０２ａで案内されて移動し、この角駒１０１の移動方向に応じて主送り腕１４の前後揺動角が決まり、取付け部材１７と主送り歯部材２の送り量が決まる。
【００２２】
図６、図７の状態において、駆動軸１０が矢印方向へ回動され、前後駆動用カム１１で前後駆動力伝達部材１２がコイルバネ１５の付勢力に抗して押動されると、角駒１０１は係合部材１０２の係合溝１０２ａに案内されて矢印α方向へ移動し、主送り腕１４が後方へ揺動する。ここで、主送り歯部材２の送り量を調節可能な布送り量調節機構１００について、図５〜図７を参照して簡単に説明する。布送り量調節機構１００は、角駒１０１及び係合溝１０２ａを有する係合部材１０２と、フレームに回動自在に支持された軸部材１０５の左端部に固着された円板１０４であって、係合部材１０２の先端部のピン１０３が係合する溝カム１０４ａを有する円板１０４と、軸部材１０５の右端部に固着された送り量調節ツマミ１０７等で構成されている。
【００２３】
送り量調節ツマミ１０７を回動操作し、軸部材１０５を介して円板１０４を回転させ、角駒１０１が矢印β方向へ移動するようにすると、前後駆動力伝達部材１２が前後駆動用カム１１により前後に駆動されても、主送り腕１４の前後へ揺動しなくなり、取付け部材１７と主送り歯部材２が送り作動しなくなり、角駒１０１の移動方向と矢印β方向の角度が大きくなると、主送り歯部材２の送り量も大きくなる。図１に示すように、例えば、送り量調節ツマミ１０７を回動操作し、揺動量０を含めて４段階に調節できるようになっている。尚、軸部材１０５には板バネ１０６が摺接している。
【００２４】
差動送り装置６について説明する。
図６〜図１３に示すように、差動送り装置６は、差動送り歯部材４を主送り歯部材２と一体的に上下動させるとともに主送り歯部材２に対して前後方向へ所定ストローク相対移動自在に支持するスライド機構２０と、主送り歯部材２の送り量に対する差動送り歯部材４の送り量の比を無段階的に切換え可能に、差動送り歯部材４と主送り歯部材２を作動的に連結する差動送り連結機構２２を有する。
【００２５】
スライド機構２０は、差動送り歯部材４に固定された平面視逆コ字型（図８参照）の連結金具２６を有し、この連結金具の１対の支持部２６ａを、主送り歯部材２を貫通し前後に突出し且つ主送り歯部材２に止めネジ２５ａで固定された軸部材２５に摺動自在に外嵌させるとともに、連結金具に形成された長孔２６ｂに、主送り歯部材２から左方へ突出したピン２ａを係合させることにより、差動送り歯部材４が主送り歯部材２と一体的に上下動し、主送り歯部材２に対して相対的に回転せずに前後方向へ所定ストローク相対移動自在に支持されている。連結金具２６の前側の支持部２６ａと主送り歯部材２の間において、軸部材２５には圧縮コイルバネ２１（図８では省略）が外装され、差動送り歯部材４は主送り歯部材２に対して前方へ付勢されている。
【００２６】
差動送り連結機構２２は、主送り腕１４に高さ方向途中部が枢着され且つ上端部が連結金具２６（つまり、差動送り歯部材４）に作動的に連結され且つ下半分に円弧状の係合部３０ａを有するリンク部材３０と、リンク部材３０の円弧状の係合部３０ａに係合した係合ピン部材４２（突起状係合部）を含み、この係合ピン部材４２の係合部３０ａにおける高さ方向位置を変更することにより差動送り連結機構２２の前記送り量の比を無段階的に切換える切換え操作機構３１を有する。この円弧状の係合部３０ａは、貫通したガイド溝であるが、係合ピン部材４２の高さ方向の位置を変更可能とするならば貫通させる必要はない。そして、係合部３０ａの円弧の中心が枢支軸４３ｂとは同じ側にあり、それが縫製中に枢支軸４３ｂの中心軸線を通過するように、係合部３０ａの円弧は形成されている。尚、連結金具２６が連結部材に相当する。
【００２７】
主送り腕１４の左側の屈曲部１４ａから左方へ突出した軸部材３５（枢着部）に、リンク部材３０の途中部が枢着されている。差動送り歯部材４が固着された連結金具２６の左端部からピン３６が左方へ突設され、このピン３６にリンク部材３０の上端部のＵ形の溝状係合部３０ｂが回動自在に係合している。主送り腕１４が前後へ揺動すると、リンク部材３０が係合ピン部材４２を中心として揺動し、このリンク部材３０から前後駆動力が差動送り歯部材４に伝達され、差動送り歯部材４が前後送り作動する。前記圧縮コイルバネ２１により、差動送り歯部材４と連結金具２６を介してリンク部材３０が常時回転付勢されるため、係合部３０ａに係合する係合ピン部材４２のガタつきを防止できる。尚、圧縮コイルバネ２１は必須でなく省略可能であり、ピン３６と溝状係合部３０ｂが可動連結手段に相当する。
【００２８】
切換え操作機構３１は、ロックミシン１のフリーベッド部８３に設けたダイヤル部材４０と、このダイヤル部材４０の回動作動を係合ピン部材４２の高さ方向移動に変換する変換機構４５を有する。変換機構４５は、ダイヤル部材４０のギヤ４０ａに噛合するセクターギヤ４１ｃを有し枢支軸４１ａに枢支された揺動部材４１と、前記係合ピン部材４２を後端部に固着し枢支軸４３ｂに枢支された切換え揺動体４３を有し、切換え揺動体４３の後端部分に形成された長孔４３ａに、揺動部材４１の後端部のピン４１ｂが挿入されている。ダイヤル部材４０を回動作動させると、揺動部材４１が枢支軸４１ａを中心として揺動するとともに、切換え揺動体４３が枢支軸４３ｂを中心として上下に揺動するため、切換え揺動体４３の後端部の係合ピン部材４２が上下動しその高さ位置が切換えられる。
また、ダイヤル部材４０の半径をそのギヤ４０ａの半径より大きくし、操作されるダイヤル部材４０の歯車（ギヤ４０ａ、セクターギヤ４１ｃ）を介して揺動部材４１、切換え揺動体４３を揺動するように構成されているので、省力化が図られる。更に、縫製中に送り歯１，３とともに揺動するリンク部材３０によってダイヤル部材４０が逆に回転させられることが防止されている。
【００２９】
ここで、主送り歯１に対して差動送り歯３を差動送りさせる原理について説明する。切換え操作機構３１により係合ピン部材４２の高さ位置を切換え、図１０、図１１に示すように、係合ピン部材４２をリンク部材３０の円弧状の係合部３０ａの下端部分に係合させると、枢支軸１３から軸部材３５までの距離ｂ２が枢支軸１３からピン部材１６までの距離ｂ１の約０．６倍であるのに対して、ピン部材４２からピン部材３６までの距離ｃ２がピン部材４２から軸部材３５までの距離ｃ１の約１．３倍になるので、主送り歯１の送り量ａの約０．６×１．３倍の送り量０．８ａが差動送り歯３の送り量になる。
【００３０】
また、切換え操作機構３１により係合ピン部材４２の高さ位置を切換え、図１２、図１３に示すように、係合ピン部材４２をリンク部材３０の円弧状の係合部３０ａの上端部に係合させると、枢支軸１３から軸部材３５までの距離ｂ２が枢支軸１３からピン部材１６までの距離ｂ１の約０．６倍であるのに対して、ピン部材４２からピン部材３６までの距離ｃ２がピン部材４２から軸部材３５までの距離ｃ１の約３．２倍になるので、主送り歯１の送り量ａの約０．６×３．２だけ増幅された送り量２ａが差動送り歯３の送り量になる。
【００３１】
また、図示していないが、図１０、図１１の状態から、係合ピン部材４２を上昇させ、ピン部材４２からピン部材３６までの距離ｃ２がピン部材４２から軸部材３５までの距離ｃ１の約１．６倍にすると、主送り歯１の送り量ａの約０．６×３．２倍の送り量ａが差動送り歯３の送り量になり、主送り歯部材２と差動送り歯部材４が一体的に相等しい送り量で送り作動する。尚、図１４は、駆動軸１０の回転角に対する揺動量ａの主送り歯１と、揺動量２ａ、ａ、0.8 ａの差動送り歯部材３の前後送り作動を示す図である。この２つの送り歯のうち、後側に位置する主送り歯１の前後移動範囲が主に針落ち点の近傍であって使用者の望む縫目のピッチに影響し、前側に位置する差動送り歯３の前後移動範囲が主に主送り歯１の前後移動範囲の手間側にある。そのため、縫製中の布は押さ足８５によって押さえつけられ、布の移動がある程度制限された状態であり、伸縮性の大きい布が押さえられた状態で主送り歯１で後方へ移動されると伸びるが、主送り歯１の送り量に対して差動送り歯３の送り量が大きい場合には、同時に差動送り歯３によって主送り歯１より多く送られるので、その主送り歯１による引っ張りが解消された後の縮みが吸収され、縫製中の布縮みが防止できるのである。特に伸縮性の大きいニット地やジャージ地等ではこのように差動送り縫いが有効になる。尚、主送り歯１及び差動送り歯３は、駆動軸１０によって縫い針が布から抜けた所定のタイミングで布送り動作を行う。
【００３２】
上下駆動機構７について説明する。
図６〜図９に示すように、上下駆動機構７は、駆動軸１０と、駆動軸１０に固着された上下駆動用カム５０と、上下駆動用カム５０に係合する上下駆動力伝達部材５１と、前後駆動機構５と共通の枢支軸１３であって上下駆動力伝達部材５１の下端部が固着された枢支軸１３と、枢支軸１３の左端部に固着された揺動リンク部材５２と、揺動リンク部材５２にピン５４にて連結された縦向きの可動部材５３を有する。
【００３３】
駆動軸１０の右端部には、脚柱部８１の右側へ突出し手動にて駆動軸１０を回動させることのできる回動操作部材９１が連結されている。上下駆動力伝達部材５１は、上下駆動用カム５０に係合する二股カム従動部５４を有し、主送り腕１４の１対の屈曲部１４ａの間に配設され、上下駆動力伝達部材５１の上下方向中段部に形成された円弧状の長孔５１ａに、主送り腕１４のピン部材１６が挿通している。
【００３４】
図６、図７に示すように、二股カム従動部５４は、相対向する第１従動部５４ａと第２従動部５４ｂからなり、上下駆動用カム５０により、第１従動部５４ａが押動され、上下駆動力伝達部材５１が後方へ揺動すると、揺動リンク部材５２が枢支軸１３を中心として上方へ揺動し、可動刃５５と差動送り歯部材４が上昇駆動され、第２従動部５４ｂが押動される。上下駆動力伝達部材５１が前方へ揺動すると、可動刃５５と差動送り歯部材４が下降駆動される。
【００３５】
可動部材５３は鉛直姿勢の板状フレーム９５（図８参照）の左側に位置し、可動部材５３の上端部には左右方向向きの軸部５７（ピン部材）が一体形成されている。この軸部５７と前記ピン５４は、可動部材５３から右方へ突出し、板状フレーム９５に形成された縦向きの長孔５８，５９に挿通して上下方向へガイドされている。尚、軸部５７の前後量端面は面取りされて、長孔５８の鉛直面に夫々摺接している。
【００３６】
図８に示すように、軸部５７は可動部材５３から左方へも長く伸び、軸部５７には軸部材５７ａが摺動自在に挿通し、この軸部材５７ａに板状フレーム９５の右側において可動刃５５が固着されている。一方、固定刃５６は板状フレーム９５の上端に針板８４の上方へ僅かに突出するように取付けられている。軸部材５７ａの左端部には止め輪５７ｂが取付けられ、止め輪５７ｂと軸部５７の左端間において軸部材５７ｂに圧縮コイルバネ５７ｃが外装され、このコイルバネ５７ｃの付勢力で可動刃５５が固定刃５６と摺接状態を保持し、上下動する可動刃５５と固定刃５６との協働により、後方へ送られる縫製直前の布端部を切断するようになっている。
【００３７】
板状フレーム９５には、揺動伝達部材６０の前端部が枢支ピン６１により枢着され、揺動伝達部材６０の途中部の上端近傍部に、差動送り歯部材４の前端下面部を摺動自在に支持して、差動送り歯部材４に上下駆動力を伝達する軸状の伝達部６２が左方突出状に形成されている。揺動伝達部材６０の他端部には、長軸が枢支ピン６１の方に向く長孔６３が形成され、この長孔６３に可動部材５３の軸部５７が係合している（図１６〜図１９参照）。
【００３８】
前記枢支ピン６１には偏心ピン部６６が一体形成され、この偏心ピン部６６に揺動伝達部材６０の前端部が枢支されている。図１６は可動刃５５と差動送り歯部材４が上昇限界位置に位置した状態を示し、図１７は可動刃５５及び差動送り歯部材４が下降限界位置に位置した状態を示し、伝達部６２と差動送り歯部材４は、可動刃５５の上下ストロークｈの約２／３のストロークで上下動する。
【００３９】
前記高さ位置調節装置について説明する。
高さ位置調節装置は、前記上下駆動機構７に含まれ差動送り歯３の高さ位置を微調節する為の第１調節機構８と、前記前後駆動機構５に含まれ主送り歯１の高さ位置を微調節する為の第２調節機構９からなる。
【００４０】
第１調節機構８は、図１５〜図１９に示すように、揺動伝達部材６０を板状フレーム９５に枢支する枢支ピン６１に一体形成された偏心ピン部６６を含み、揺動伝達部材６０の伝達部６２の高さ位置を微調節可能な偏心機構６５を有する。枢支ピン６１の軸心６１ａに対して偏心ピン部６６の軸心６６ａは、偏心量ｅ（例えば１．５mm）だけ偏心しているので、偏心ピン部６６をスクリュードライバで回動させることで、全方向へ偏心量ｅで偏心させ、伝達部６２の高さ位置を微調節し、差動送り歯部材４の高さ位置を微調節することができる。尚、上述した微調整においては、フレームに螺合した止めビスをスクリュードライバーで緩めて偏心ピン部６６を所望の位置に回転させ、微調整後止めビスを締めて偏心ピン部６６を固定する。
【００４１】
図１６、図１８、図１９は可動刃５５を上昇限界位置に上昇させた際の第１調節機構８の状態を示し、図１６の第１調節機構８の状態から、例えば、偏心ピン部６６を図において反時計回りに９０度回転させ、図１８に示すように、枢支ピン６１の軸心６１ａに対して偏心ピン部６６の軸心６６ａを偏心させ、偏心ピン部６６の高さ位置がｅだけ高くなると、揺動伝達部材６０が略軸部５７の軸心５７ａを中心として図において時計回りに回転し、伝達部６２の高さは約ｅ／２高くなる。
【００４２】
図示していないが、図１６の第１調節機構８の状態から、例えば、偏心ピン部６６を図において時計回りに９０度回転させ、枢支ピン６１の軸心６１ａに対して偏心ピン部６６の軸心６６ａを偏心させ、偏心ピン部６６の高さ位置がｅだけ高くなると、揺動伝達部材６０が略軸部５７の軸心５７ａを中心として図において反時計回りに回動し、伝達部６２の高さは約ｅ／２低くなる。
【００４３】
また、図１６の第１調節機構８の状態から、例えば、偏心ピン部６６を図において１８０度回転させ、図１９に示すように、枢支ピン６１の軸心６１ａに対して偏心ピン部６６の軸心６６ａを偏心させ、偏心ピン部６６を左方へ２ｅ移動すると、偏心ピン部６６の軸心６６ａの高さ位置は変化しないが、長孔６３の案内作用により、偏心ピン部６６の軸心６６ａと軸部５７の軸心５７ａ間の距離が短くなるため、伝達部６２の高さも低くなる。
【００４４】
このように、伝達部６２の高さ位置は、偏心ピン部６６の高さ位置の変化だけでなく、偏心ピン部６６の軸心６６ａと軸部５７の軸心５７ａ間の距離の変化によっても調節される。このように、偏心ピン部６６を回動させることにより、伝達部６２の高さ位置つまり差動送り歯３の高さ位置を微調節できる。
【００４５】
第２調節機構９は、図１５、図２０〜図２２に示すように、主送り腕１４のピン部材１６に枢支された取付け部材１７に昇降自在にガイドされ、主送り歯部材２がビス７１で固定された昇降部材７０を有し、昇降部材７０は取付け部材１７に１対のビス７２で締結解除可能に締結されている。
【００４６】
取付け部材１７は断面コの字型に形成され、取付け部材１７の間に昇降部材７０が配設されている。昇降部材７０には鉛直向きのガイドピン７３が挿通され、止め輪７３ａで固定されている。ガイドピン７３の上下両端部分は取付け部材１７の上下両端部を挿通し昇降自在にガイドされている。取付部材１７の後端部には上下に長い左右１対の長孔７５が形成されており、取付部材１７の後側から１対のビス７２が１対の長孔７５を挿通し昇降部材７０に螺着されている。つまり、１対のビス７２を緩めて、主送り歯部材２を、図２１に示す上昇限界位置と図２２に示す下降限界位置の間の所望の位置へ移動させ、１対のビス７２を締めると、その高さ位置に主送り歯部材２を固定することができる。
【００４７】
このロックミシンＭの作用・効果について説明する。
差動送り装置６において、主送り歯部材２に差動送り歯部材４をスライド機構２０を介して支持し、差動送り連結機構２２により差動送り歯部材４と主送り歯部材２とを作動的に連結し、主送り歯部材２の送り量に対する差動送り歯部材４の送り量の比を無段階的に切換え可能に構成したので、差動送り装置６の構造が簡単且つ小型になりその製作コストを格段に低減できる。
【００４８】
差動送り連結機構２２は、主送り歯部材２に送り駆動力を伝達する主送り腕１４に高さ方向途中部が枢着され且つ上端部が差動送り歯部材４に作動的に連結され且つ下半分に円弧状の係合部３０ａを有するリンク部材３０を備え、係合部３０ａに係合した係合ピン部材４２を含み、この係合ピン部材４２の係合部３０ａにおける高さ方向位置を変更することにより差動送り連結機構２２の前記送り量の比を無段階的に切換える切換え操作機構３１を設けたので、縫製対象の布の伸縮性に応じて、前記送り量の比を適正な比に簡単に設定できるようになる。
【００４９】
切換え操作機構３１は、ミシンＭのフリーベッド部８３に設けたダイヤル部材４０と、このダイヤル部材４０の回動作動を係合ピン部材４２の高さ方向移動に変換する変換機構４５を備えたので、ダイヤル部材４０を回動作動させることで、変換機構４５を介して係合ピン部材４２を高さ方向へ移動させ、係合ピン部材４２の係合部３０ａにおける高さ位置を簡単に変更することが可能になる。
上述した実施の形態では、無段階に差動送り比を回転操作可能なダイヤル部材４０で行ったが、連続的に操作可能な部材であればスライド式のレバーであっても構わない。無段階に設定する構成であれば、複数個の押しボタンによる多段階的な設定に比べて、布の伸びに良好な差動比を適合させることは容易である。
【００５０】
【発明の効果】
請求項１のミシンの差動送り装置によれば、主送り部材に対してその主送り部材の移動方向と交差する方向の一軸線の回りに枢着され、且つその枢着部を挟んでその一側部に前記切換え操作機構の突起状係合部を相対移動可能に係合させる円弧状の係合部を有するリンク部材と、差動送り歯部材に固定され、且つその差動送り歯部材を主送り歯部材と一体的に上下動させるとともに主送り歯部材に対して布送り方向へ所定ストローク相対移動自在に連結された連結部材とを備え、リンク部材における枢着部を挟んでその他側部と連結部材とを可動連結手段によって直接連結したので、縫製対象の布の伸縮性に応じて、前記送り量の比を適正な比に設定し、伸縮地に伸びが生じないように布送りを実行できるため縫製の仕上がりが良好になるとともに、リンク部材から差動送り歯部材に至る連結構成が簡単化することにより差動送り装置の構造が簡単且つ小型になりその製作コストも格段に低減する。
【００５１】
請求項２のミシンの差動送り装置によれば、可動連結手段は、リンク部材の他側部と連結部材との一方に設けられたピンと、他方に設けられピンを可動自在に係合させる溝状係合部とによって構成したので、請求項１と同様の効果を奏する。
【００５２】
【図面の簡単な説明】
【図１】本発明の実施形態に係るロックミシンの斜視図である。
【図２】ロックミシンの正面図である。
【図３】ロックミシンの左側面図である。
【図４】ロックミシンの左側面透視図である。
【図５】ロックミシンの正面透視図である。
【図６】ロックミシン内部の要部左側面図である。
【図７】ロックミシン内部の要部右側面図である。
【図８】ロックミシン内部の要部平面図である。
【図９】ロックミシン内部の要部正面図である。
【図１０】差動送り装置の作動説明図である。
【図１１】差動送り装置の作動説明図である。
【図１２】差動送り装置の作動説明図である。
【図１３】差動送り装置の作動説明図である。
【図１４】主送り歯部材と差動送り歯部材の送り量を示す図である。
【図１５】高さ位置調節機構（第１、第２調節機構）を示す図である。
【図１６】上下駆動機構の作動説明図である。
【図１７】上下駆動機構の作動説明図である。
【図１８】第１調節機構の作動説明図である。
【図１９】第１調節機構の作動説明図である。
【図２０】図１５のXX−XX線断面図である。
【図２１】第２調節機構の作動説明図である。
【図２２】第２調節機構の作動説明図である。
【符号の説明】
Ｍロックミシン
１主送り歯
２主送り歯部材
３差動送り歯
４差動送り歯部材
５前後駆動機構
６差動送り装置
７上下駆動機構
８第１調節機構
９第２調節機構
１０駆動軸
１１前後駆動用カム
１２前後駆動力伝達部材
１３枢支軸
１４主送り腕
１６ピン部材
２０スライド機構
２１圧縮コイルバネ
２６連結金具
３０リンク部材
３０ａ係合部
３０ｂ溝状係合部
３１切換え操作機構
３５軸部材
３６ピン
４２係合ピン部材
５０上下駆動用カム
５１上下駆動力伝達部材
５２揺動リンク部材
５４二股カム従動部
５５可動刃
５７軸部（ピン部材）
６０揺動伝達部材
６１枢支ピン
６２伝達部
６３長孔
６５偏心機構
６６偏心ピン部
８４針板[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a differential feed device for a sewing machine, and more particularly to a configuration in which a ratio of a feed amount of a differential feed dog member to a feed amount of a main feed dog member can be switched steplessly.
[0002]
[Prior art]
  Conventionally, a sewing machine that can sew stretchable cloth (stretchable fabric) has a differential feed dog and a main feed that feed the cloth to be sewn on the needle plate in the cloth feed direction (front-rear direction) in cooperation with the presser foot. When the feed dog is placed before and after the needle drop point of the sewing needle and the stretch ground is sewn, the differential feed dog is fed with a feed amount larger than the feed amount of the main feed dog, There is provided a differential feeding device that feeds the amount of stretch of the stretchable ground in advance with the differential feed teeth and feeds the fabric so that the stretchable ground does not stretch.
[0003]
  For example, in the differential feeding device described in Japanese Patent Application Laid-Open No. 5-317550, the main feed dog and the sub feed dog (differential feed dog) are supported by the main feed dog mounting shaft and the sub feed shaft supported so as to be movable in the front-rear direction. Provided at the tip of the feed dog mounting shaft, the main feed drive mechanism transmits the front / rear driving force to the main feed dog mounting shaft, the sub feed drive mechanism transmits the front / rear drive force to the sub feed dog mounting shaft, and the main feed dog And the auxiliary feed dog is operated to feed.
[0004]
  The main feed drive mechanism converts the rotational motion of the drive shaft into linear motion, transmits the driving force to the main feed slide rod, and swings the main feed slide rod back and forth to move back and forth to the main feed dog mounting shaft. This is a general mechanism that transmits the driving force. By sliding the main feed slide rod in its length direction, the swing amount of the main feed slide rod changes and the feed amount of the main feed dog can be adjusted. ing.
[0005]
  On the other hand, the sub-feed drive mechanism transmits the driving force due to the back-and-forth movement of the main feed dog mounting shaft to the sub-feed slide rod via a plurality of drive transmission members, and swings the sub-feed slide rod back and forth. The front / rear driving force is transmitted to the auxiliary feed dog mounting shaft. The sub-feed slide rod is slidably supported in its length direction, and by operating the differential adjustment lever and sliding the sub-feed slide rod, the swing amount of the sub-feed slide rod changes, and the auxiliary feed dog mounting shaft The forward / backward movement stroke, that is, the feed amount of the auxiliary feed dog can be adjusted.
[0006]
[Problems to be solved by the invention]
  In the differential feed device of the above publication, a main feed dog mounting shaft and a sub feed dog mounting shaft are provided, and the main feed dog and the sub feed dog are respectively supported via the pair of mounting shafts. Since it is necessary to provide a sub-feed drive mechanism that transmits the driving force generated by the forward / backward movement of the main feed dog mounting shaft to the sub-feed mounting shaft via a plurality of drive transmission members and sub-feed slide rods, a differential feed device However, it becomes a complicated and large structure with a large number of parts, and its manufacturing cost is also expensive.
[0007]
  SUMMARY OF THE INVENTION An object of the present invention is to provide a sewing machine having a simple and small structure, capable of steplessly switching the ratio of the feed amount of the differential feed dog member to the feed amount of the main feed dog member. That is.
[0008]
[Means for Solving the Problems]
  The differential feed device for a sewing machine according to claim 1, wherein the main feed dog feeds the cloth to be sewn on the needle plate.A main feed dog member provided with a differential feed dog member provided with a differential feed dog for feeding the cloth at a position in front of the main feed dog, and a main feed for transmitting a feed driving force to the main feed dog member. And a switching operation mechanism for enabling stepless switching of the ratio of the feed amount of the differential feed dog member to the feed amount of the main feed dog member.In the sewing machine differential feeder,It is pivotally attached to the main feed member about one axis in a direction intersecting the moving direction of the main feed member, and the projection-like engagement of the switching operation mechanism on one side of the pivot attachment portion A link member having an arcuate engagement portion that engages the portion so as to be relatively movable, and fixed to the differential feed dog member, and the differential feed dog member is moved up and down integrally with the main feed dog member. And a connecting member that is connected to the main feed dog member so as to be relatively movable in the cloth feeding direction by a predetermined stroke, and the other side portion and the connecting member are movablely connected with the pivoting portion of the link member interposed therebetween. Directly linked by meansIs.
[0009]
  By main feed memberThe feed driving force is transmitted to the main feed dog member,Via the link memberFor differential feed dog membersAlsoThe feed driving force is transmitted, and the main feed dog member and the differential feed dog member feed. When sewing a non-stretchable cloth,Of the differential feed dog member relative to the feed amount of the main feed dog memberWhen the ratio of the feed amounts is switched to 1: 1, the main feed dog and the differential feed dog member are integrally fed with the same feed amount.
  When sewing a stretchable fabric (stretchable fabric), the ratio of the feed amount is large for stretchable fabric with large stretchability, and the ratio of the feed amount is small for stretchable fabric with small stretchability. Depending on the elasticity of the stretch fabricin frontWhen the ratio of the feed amount is switched to an appropriate ratio, the main feed dog and the differential feed dog member feed by that ratio, and the extension amount of the stretchable area is increased by the differential feed dog with respect to the main feed dog. The cloth is fed in advance so that the stretched fabric does not stretch, and the sewing finish is improved.
[0010]
  The differential feeding device for a sewing machine according to claim 2 is the invention according to claim 1,The movable connecting means is configured by a pin provided on one of the other side portion of the link member and the connecting member, and a groove-like engaging portion provided on the other side and movably engaged with the pin.It is characterized by this.
[0011]
  Main feed memberIs driven to swing back and forth, the feed driving force is transmitted to the main feed dog, and the main feed dog operates to feed,Around one axis of the main feed member in a direction that intersects the direction of movement of the main feed memberThe pivoted link member engaged with the arcuate engagement partProtruding engagement partFrom this link memberVia a movably engaged pin and groove-like engagement partA feed driving force is transmitted to the differential feed dog member, and the differential feed dog member feeds.Other claim 1 Has the same effect as.
[0012]
[0013]
[0014]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings. This embodiment is an example in the case where the present invention is applied to a lock sewing machine for mainly sewing the edge of a cloth. However, on the basis of an operator who operates the lock sewing machine, the front side will be described as the front, and the left-right direction will be described as the left-right direction.
[0015]
  As shown in FIGS. 1 to 5, the lock sewing machine M includes a bed portion 80, a leg column portion 81 standing on the right side of the bed portion 80, and an arm portion 82 extending leftward from the upper portion of the leg column portion 81. The left end portion of the bed portion 80 is configured as a cantilevered free bed portion 83. A needle plate 84 is provided on the upper surface of the free bed portion 83, and the differential feed dog 3 and the main feed dog 1 that feed and operate so as to protrude from a long hole formed by extending the needle plate 84 in the cloth feed direction. And are arranged at the front and back. The arm portion 82 is provided with a presser foot 85 for pressing the cloth to be sewn between the main feed dog 1 and the differential feed dog 3, and a switching lever 86 for switching the presser foot 85 between the lowered position and the raised position. In cooperation with the presser foot 85 switched to the lowered position, the main feed dog 1 and the differential feedRBy the teeth 3, the cloth to be sewn on the needle plate 84 is fed in the cloth feeding direction (front-rear direction).
[0016]
  A pair of sewing needles 88 is attached to the lower end of the arm portion 82 and a needle bar 87 that is vertically moved by a needle bar vertical drive mechanism (not shown) is supported. A plurality of (for example, four) thread guides 92 and a thread guide member 89 are erected on the rear end portion of the pedestal portion 80, and a thread tension adjusting knob 90 is provided on the front surface of the pedestal portion 81. A feed amount adjustment knob 107 that adjusts the feed amount of the main feed dog 1 and a rotation operation member 91 connected to the drive shaft 10 are provided on the right side surface portion of the pedestal portion 81, and the front side of the free bed portion 83 is provided. A part of the dial member 40 of the differential feeding device 6 protrudes.
[0017]
  As shown in FIGS. 4 to 9, the lock sewing machine M includes a main feed dog member 2 having a main feed dog 1, a differential feed dog member 4 having a differential feed dog 3, and a main feed. A front / rear drive mechanism 5 for transmitting a front / rear driving force to the tooth member 2 and the differential feed dog member 4, and a differential feed capable of steplessly switching the cloth feed amount of the differential feed dog member 4 with respect to the main feed dog member 2. The height positions of the device 6, the movable blade 55, the vertical feed mechanism 7 for transmitting the vertical drive force to the main feed dog member 2 and the differential feed dog member 4, and the differential feed dog 3 and the main feed dog 1 are slightly set. An adjustable height position adjusting device (first adjusting mechanism 8 and second adjusting mechanism 9) and the like are provided.
[0018]
  The main feed dog member 2 is a main feed arm 14.(Main feed member)The second feed mechanism 9 is connected to an attachment member 17 pivotally attached to a left and right pin member 16 at the upper end of the second feed mechanism so that the height position can be adjusted. It is supported by the main feed dog member 2 via the slide mechanism 20 of the differential feed device 6, and is urged downward by the tension coil spring 18 at its front end portion so that it can freely slide on the transmission portion 62 of the swing transmission member 60. It is supported by.
[0019]
  The front-rear drive mechanism 5 will be described.
  The front-rear drive mechanism 5 includes a drive shaft 10 that is rotationally driven by a sewing machine motor (not shown) in the bed 80, a front-rear drive cam 11 that is fixed to the drive shaft 10, and a front-rear drive cam 11 that is substantially vertical. A front / rear driving force transmission member 12 in which the middle portion is slidably contacted, and a main feed arm 14 pivotally supported by a horizontal pivot shaft 13 in the left-right direction and rotatably supported by the frame at the lower end portion; A lower end portion of the front / rear driving force transmission member 12 is pin-coupled to the lever portion 14b of the main feed arm 14 so as to be swingable.
[0020]
  The front / rear driving force transmission member 12 is disposed on the rear side of the driving shaft 10 and is biased forward and obliquely upward by a tension coil spring 15 having one end connected to the frame, so that the front end of the middle portion of the front / rear driving force transmission member 12 slides. The surface 12a is slidably in contact with the front and rear drive cam 11. The main feed arm 14 has a pair of bent portions 14a at both left and right end portions, the lower ends of the bent portions 14a are pivotally supported by the pivot shaft 13, and the lever portion 14b is moved forward from the lower end of the right bent portion 14a. It extends to. The pin member 16 that pivotally supports the mounting member 17 is attached to the upper end portions of the pair of left and right bent portions 14a so as not to slide and to swing.
[0021]
  A square piece 101 of the feed amount adjusting mechanism 100 is rotatably connected to the upper end portion of the front / rear driving force transmission member 12, and the square piece 101 is engaged with an engagement groove of an engagement member 102 supported around the horizontal axis by the frame. 102a is slidably engaged with 102a. When the front / rear driving force transmission member 12 is driven back and forth by the front / rear driving cam 11, the square piece 101 is guided and moved by the engagement groove 102 a, and the main feed arm 14 moves according to the moving direction of the square piece 101. The forward / backward swing angle is determined, and the feed amounts of the attachment member 17 and the main feed dog member 2 are determined.
[0022]
  In the state of FIGS. 6 and 7, when the drive shaft 10 is rotated in the direction of the arrow and the front / rear drive force transmission member 12 is pushed against the biasing force of the coil spring 15 by the front / rear drive cam 11, 101 is guided in the engagement groove 102a of the engagement member 102 and moves in the direction of the arrow α, and the main feed arm 14 swings backward. Here, the cloth feed amount adjusting mechanism 100 capable of adjusting the feed amount of the main feed dog member 2.InThis will be briefly described with reference to FIGS. The cloth feed amount adjusting mechanism 100 includes an engagement member 102 having a square piece 101 and an engagement groove 102a, and a disc 104 fixed to the left end portion of a shaft member 105 that is rotatably supported by a frame. A disc 104 having a groove cam 104a with which a pin 103 at the tip end portion of the engaging member 102 is engaged, a feed amount adjusting knob 107 fixed to the right end portion of the shaft member 105, and the like.
[0023]
  When the feed amount adjusting knob 107 is rotated to rotate the disk 104 via the shaft member 105 so that the square piece 101 moves in the arrow β direction, the front / rear driving force transmitting member 12 is moved to the front / rear driving cam 11. The main feed arm 14 does not swing back and forth even when driven by the front and rear, the attachment member 17 and the main feed dog member 2 do not feed, and the angle of the square piece 101 and the direction of the arrow β increase. The feed amount of the main feed dog member 2 is also increased. As shown in FIG. 1, for example, the feed amount adjusting knob 107 can be rotated and adjusted in four stages including a swing amount of zero. A leaf spring 106 is in sliding contact with the shaft member 105.
[0024]
  The differential feeder 6 will be described.
  As shown in FIGS. 6 to 13, the differential feed device 6 moves the differential feed dog member 4 up and down integrally with the main feed dog member 2 and has a predetermined stroke in the front-rear direction with respect to the main feed dog member 2. The differential feed dog member 4 and the main feed dog are switchable in a stepless manner so that the ratio of the feed amount of the differential feed dog member 4 with respect to the feed amount of the main feed dog member 2 can be switched steplessly. A differential feed coupling mechanism 22 for operatively coupling the members 2 is provided.
[0025]
  The slide mechanism 20 includes a connecting metal fitting 26 having a reverse U-shape in plan view (see FIG. 8) fixed to the differential feed dog member 4, and a pair of support portions 26a of the connecting metal fitting is connected to the main feed dog member. 2, is slidably fitted to a shaft member 25 that protrudes forward and backward and is fixed to the main feed dog member 2 with a set screw 25 a, and the main feed dog member 2 is inserted into a long hole 26 b formed in the connecting metal fitting. The differential feed dog member 4 moves up and down integrally with the main feed dog member 2 by engaging the pin 2a protruding to the left from the main feed dog member 2 without rotating relative to the main feed dog member 2. It is supported so as to be movable in a predetermined stroke relative to the front-rear direction. A compression coil spring 21 (not shown in FIG. 8) is externally mounted on the shaft member 25 between the front support portion 26 a of the coupling metal 26 and the main feed dog member 2, and the differential feed dog member 4 is attached to the main feed dog member 2. It is biased forward.
[0026]
  The differential feed connecting mechanism 22 is pivotally attached to the main feed arm 14 in the middle in the height direction, and the upper end is operatively connected to the connecting metal fitting 26 (that is, the differential feed dog member 4) and is circular in the lower half. A link member 30 having an arcuate engagement portion 30a and an engagement pin member 42 engaged with the arcuate engagement portion 30a of the link member 30(Protruding engagement part)And a switching operation mechanism 31 that switches the ratio of the feed amounts of the differential feed coupling mechanism 22 steplessly by changing the position in the height direction of the engagement portion 30a of the engagement pin member 42. The arcuate engagement portion 30a is a guide groove that penetrates, but does not need to be penetrated if the position of the engagement pin member 42 in the height direction can be changed. The arc of the engaging portion 30a is formed so that the center of the arc of the engaging portion 30a is on the same side as the pivot shaft 43b and passes through the central axis of the pivot shaft 43b during sewing. Yes.The connecting fitting 26 corresponds to a connecting member.
[0027]
  A shaft member 35 protruding leftward from the bent portion 14a on the left side of the main feed arm 14(Pivoting part)Moreover, the middle part of the link member 30 is pivotally attached. Connecting bracket to which the differential feed dog member 4 is fixed26A pin 36 protrudes leftward from the left end of the U-shaped member.GrooveThe engaging portion 30b is rotatably engaged. When the main feed arm 14 swings back and forth, the link member 30 swings around the engaging pin member 42, and the front / rear driving force is transmitted from the link member 30 to the differential feed dog member 4. The member 4 is moved forward and backward. Since the link member 30 is always urged to rotate by the compression coil spring 21 via the differential feed dog member 4 and the connecting fitting 26, it is possible to prevent the engagement pin member 42 engaged with the engagement portion 30a from rattling. . The compression coil spring 21 is not essential and can be omitted.Thus, the pin 36 and the groove-like engaging portion 30b correspond to the movable connecting means.
[0028]
  The switching operation mechanism 31 includes a dial member 40 provided on the free bed portion 83 of the lock sewing machine 1 and a conversion mechanism 45 that converts a rotation operation of the dial member 40 into a movement in the height direction of the engagement pin member 42. The conversion mechanism 45 has a sector gear 41c that meshes with the gear 40a of the dial member 40, and has a swinging member 41 pivotally supported by the pivotal support shaft 41a and the engaging pin member 42 fixed to the rear end portion thereof. A switching rocking body 43 pivotally supported by the shaft 43 b is provided, and a pin 41 b at the rear end of the rocking member 41 is inserted into a long hole 43 a formed in the rear end portion of the switching rocking body 43. When the dial member 40 is turned, the swing member 41 swings about the pivot shaft 41a and the switching swing body 43 swings up and down about the pivot shaft 43b. The engagement pin member 42 at the rear end portion moves up and down, and its height position is switched.
  Further, the radius of the dial member 40 is made larger than the radius of the gear 40a, and the swing member 41 and the switching swing body 43 are swung via the gears (gear 40a, sector gear 41c) of the dial member 40 to be operated. Therefore, labor saving is achieved. Further, the dial member 40 is prevented from being rotated in reverse by the link member 30 that swings together with the feed dogs 1 and 3 during sewing.
[0029]
  Here, the principle of differentially feeding the differential feed dog 3 with respect to the main feed dog 1 will be described. The height position of the engagement pin member 42 is switched by the switching operation mechanism 31, and the engagement pin member 42 is engaged with the lower end portion of the arcuate engagement portion 30a of the link member 30 as shown in FIGS. Then, the distance b2 from the pivot shaft 13 to the shaft member 35 is about 0.6 times the distance b1 from the pivot shaft 13 to the pin member 16, whereas the distance from the pin member 42 to the pin member 36 is Since the distance c2 is about 1.3 times the distance c1 from the pin member 42 to the shaft member 35, the feed amount 0.8a which is about 0.6 × 1.3 times the feed amount a of the main feed dog 1 is different. It becomes the feed amount of the moving feed dog 3.
[0030]
  Further, the height position of the engaging pin member 42 is switched by the switching operation mechanism 31, and the engaging pin member 42 is moved to the upper end portion of the arc-shaped engaging portion 30a of the link member 30 as shown in FIGS. When engaged, the distance b2 from the pivot shaft 13 to the shaft member 35 is about 0.6 times the distance b1 from the pivot shaft 13 to the pin member 16, whereas the pin member 42 to the pin member 36 Is about 3.2 times the distance c1 from the pin member 42 to the shaft member 35, the feed amount 2a amplified by about 0.6 × 3.2 of the feed amount a of the main feed dog 1 Becomes the feed amount of the differential feed dog 3.
[0031]
  Although not shown, the engagement pin member 42 is raised from the state of FIGS. 10 and 11, and the distance c2 from the pin member 42 to the pin member 36 is the distance c1 from the pin member 42 to the shaft member 35. When the feed amount is about 1.6 times, the feed amount a that is about 0.6 × 3.2 times the feed amount a of the main feed dog 1 becomes the feed amount of the differential feed dog 3, which is different from the main feed dog member 2. The feed dog member 4 integrally feeds with the same feed amount. FIG. 14 is a view showing the forward / backward feed operation of the main feed dog 1 with the swing amount a with respect to the rotation angle of the drive shaft 10 and the differential feed dog member 3 with the swing amounts 2a, a and 0.8a. Of these two feed dogs, the forward / backward movement range of the main feed dog 1 located on the rear side is mainly in the vicinity of the needle drop point, affecting the stitch pitch desired by the user, and the differential located on the front side. The longitudinal movement range of the feed dog 3 is mainly on the labor side of the longitudinal movement range of the main feed dog 1. Therefore, the cloth being sewn is pressed by the pressing foot 85, and the movement of the cloth is restricted to some extent. If the cloth having high elasticity is held down, the cloth is stretched when moved backward by the main feed dog 1. When the feed amount of the differential feed dog 3 is larger than the feed amount of the main feed dog 1, the differential feed dog 3 feeds more than the main feed dog 1 at the same time. The shrinkage after the cancellation is absorbed, and the fabric shrinkage during sewing can be prevented. In particular, differential feed stitching is effective in knitted fabrics, jersey fabrics, and the like that have great elasticity. The main feed dog 1 and the differential feed dog 3 perform a cloth feed operation at a predetermined timing when the sewing needle is removed from the cloth by the drive shaft 10.
[0032]
  The vertical drive mechanism 7 will be described.
  As shown in FIGS. 6 to 9, the vertical drive mechanism 7 includes a drive shaft 10, a vertical drive cam 50 fixed to the drive shaft 10, and a vertical drive force transmission member 51 that engages with the vertical drive cam 50. A pivot shaft 13 common to the front-rear drive mechanism 5 and having the lower end portion of the vertical drive force transmission member 51 secured thereto, and a swing link member secured to the left end portion of the pivot shaft 13 52 and a vertically movable member 53 connected to the swing link member 52 by a pin 54.
[0033]
  A rotation operation member 91 that protrudes to the right side of the pedestal column 81 and can manually rotate the drive shaft 10 is connected to the right end portion of the drive shaft 10. The vertical drive force transmission member 51 has a bifurcated cam driven portion 54 that engages with the vertical drive cam 50, and is disposed between the pair of bent portions 14 a of the main feed arm 14. The pin member 16 of the main feed arm 14 is inserted into an arc-shaped long hole 51a formed in the middle part in the vertical direction.
[0034]
  As shown in FIGS. 6 and 7, the bifurcated cam follower 54 includes a first follower 54 a and a second follower 54 b that are opposed to each other, and the first follower 54 a is pushed by the vertical drive cam 50. When the vertical driving force transmission member 51 swings backward, the swing link member 52 swings upward about the pivot shaft 13, and the movable blade 55 and the differential feed dog member 4 are driven upward, and the second The follower 54b is pushed. When the vertical driving force transmission member 51 swings forward, the movable blade 55 and the differential feed dog member 4 are driven downward.
[0035]
  The movable member 53 is located on the left side of the plate-like frame 95 (see FIG. 8) in the vertical posture, and a shaft portion 57 (pin member) facing in the left-right direction is integrally formed at the upper end portion of the movable member 53. The shaft portion 57 and the pin 54 protrude rightward from the movable member 53, and are inserted vertically through elongated holes 58 and 59 formed in the plate-like frame 95 to be guided in the vertical direction. Note that the front and rear end faces of the shaft portion 57 are chamfered and are in sliding contact with the vertical surfaces of the long holes 58, respectively.
[0036]
  As shown in FIG. 8, the shaft portion 57 extends to the left from the movable member 53, and a shaft member 57 a is slidably inserted into the shaft portion 57, and is inserted into the shaft member 57 a on the right side of the plate frame 95. The movable blade 55 is fixed. On the other hand, the fixed blade 56 is attached to the upper end of the plate-like frame 95 so as to slightly protrude above the needle plate 84. A retaining ring 57b is attached to the left end portion of the shaft member 57a. A compression coil spring 57c is externally mounted on the shaft member 57b between the retaining ring 57b and the left end of the shaft portion 57, and the movable blade 55 is fixed by the urging force of the coil spring 57c. The cloth end portion just before sewing sent to the rear is cut by the cooperation of the movable blade 55 and the fixed blade 56 which are kept in sliding contact with the movable member 56 and move up and down.
[0037]
  The front end portion of the swing transmission member 60 is pivotally attached to the plate-like frame 95 by the pivot pin 61, and the front end lower surface portion of the differential feed dog member 4 is disposed in the vicinity of the upper end of the middle portion of the swing transmission member 60. A shaft-shaped transmission portion 62 that is slidably supported and transmits the vertical driving force to the differential feed dog member 4 is formed to project leftward. A long hole 63 whose long axis faces the pivot pin 61 is formed at the other end of the swing transmitting member 60, and the shaft 57 of the movable member 53 is engaged with the long hole 63 (see FIG. 16 to 19).
[0038]
  An eccentric pin portion 66 is integrally formed on the pivot pin 61, and the front end portion of the swing transmission member 60 is pivotally supported on the eccentric pin portion 66. 16 shows a state where the movable blade 55 and the differential feed dog member 4 are located at the ascent limit position, and FIG. 17 shows a state where the movable blade 55 and the differential feed dog member 4 are located at the descending limit position. 62 and the differential feed dog member 4 move up and down with a stroke of about 2/3 of the up and down stroke h of the movable blade 55.
[0039]
  The height position adjusting device will be described.
  The height position adjusting device is included in the vertical drive mechanism 7 and includes a first adjustment mechanism 8 for finely adjusting the height position of the differential feed dog 3 and the front and rear drive mechanism 5 of the main feed dog 1. It comprises a second adjustment mechanism 9 for finely adjusting the height position.
[0040]
  As shown in FIGS. 15 to 19, the first adjusting mechanism 8 includes an eccentric pin portion 66 integrally formed with a pivot pin 61 that pivotally supports the swing transmission member 60 on the plate frame 95, and transmits the swing transmission. An eccentric mechanism 65 capable of finely adjusting the height position of the transmission portion 62 of the member 60 is provided. Since the shaft center 66a of the eccentric pin portion 66 is eccentric by the amount of eccentricity e (for example, 1.5 mm) with respect to the shaft center 61a of the pivotal support pin 61, by rotating the eccentric pin portion 66 with a screw driver, It is possible to finely adjust the height position of the differential feed dog member 4 by decentering in all directions by the eccentric amount e and finely adjusting the height position of the transmission portion 62. In the fine adjustment described above, the set screw screwed to the frame is loosened with a screw driver, the eccentric pin portion 66 is rotated to a desired position, and after the fine adjustment, the set screw is tightened to fix the eccentric pin portion 66.
[0041]
  16, 18 and 19 show the state of the first adjustment mechanism 8 when the movable blade 55 is raised to the ascent limit position. From the state of the first adjustment mechanism 8 in FIG. As shown in FIG. 18, the shaft center 66 a of the eccentric pin portion 66 is eccentric with respect to the shaft center 61 a of the pivot support pin 61, and the height position of the eccentric pin portion 66 is rotated. Is increased by e, the rocking transmission member 60 is rotated clockwise in the drawing about the axial center 57a of the shaft portion 57, and the height of the transmission portion 62 is increased by about e / 2.
[0042]
  Although not shown, from the state of the first adjustment mechanism 8 of FIG. 16, for example, the eccentric pin portion 66 is rotated 90 degrees clockwise in the drawing, and the eccentric pin portion 66 is rotated with respect to the axis 61a of the pivot pin 61. When the shaft center 66a is decentered and the height position of the eccentric pin portion 66 is increased by e, the rocking transmission member 60 is rotated counterclockwise in the drawing about the shaft center 57a of the shaft portion 57, and transmitted. The height of the part 62 is reduced by about e / 2.
[0043]
  Further, for example, the eccentric pin portion 66 is rotated 180 degrees in the drawing from the state of the first adjusting mechanism 8 in FIG. 16, and the eccentric pin portion 66 with respect to the axis 61 a of the pivot pin 61 as shown in FIG. 19. When the eccentric pin portion 66 is moved 2e to the left, the height position of the eccentric pin portion 66 does not change, but the guide action of the long hole 63 causes the eccentric pin portion 66 to move. Since the distance between the shaft center 66a and the shaft center 57a of the shaft portion 57 is shortened, the height of the transmission portion 62 is also reduced.
[0044]
  Thus, the height position of the transmission portion 62 is not only due to the change in the height position of the eccentric pin portion 66 but also due to the change in the distance between the shaft center 66a of the eccentric pin portion 66 and the shaft center 57a of the shaft portion 57. Adjusted. Thus, by rotating the eccentric pin portion 66, the height position of the transmission portion 62, that is, the height position of the differential feed dog 3 can be finely adjusted.
[0045]
  As shown in FIGS. 15 and 20 to 22, the second adjusting mechanism 9 is guided by an attachment member 17 pivotally supported by the pin member 16 of the main feed arm 14 so that the main feed dog member 2 is screwed. Fixed at 71TheThe elevating member 70 is provided, and the elevating member 70 is fastened to the attachment member 17 with a pair of screws 72 so that the fastening can be released.
[0046]
  The attachment member 17 is formed in a U-shaped cross section, and an elevating member 70 is disposed between the attachment members 17. A vertically oriented guide pin 73 is inserted into the elevating member 70 and fixed by a retaining ring 73a. The upper and lower end portions of the guide pin 73 are guided through the upper and lower end portions of the mounting member 17 so as to be movable up and down. A pair of left and right elongated holes 75 that are long in the vertical direction are formed at the rear end of the mounting member 17, and a pair of screws 72 are inserted from the rear side of the mounting member 17 through the pair of elongated holes 75. It is screwed on. That is, the pair of screws 72 are loosened, the main feed dog member 2 is moved to a desired position between the rising limit position shown in FIG. 21 and the lowering limit position shown in FIG. 22, and the pair of screws 72 are tightened. The main feed dog member 2 can be fixed at the height position.
[0047]
  The operation and effect of the lock sewing machine M will be described.
  In the differential feed device 6, the differential feed dog member 4 is supported on the main feed dog member 2 via the slide mechanism 20, and the differential feed dog member 4 and the main feed dog member 2 are connected by the differential feed coupling mechanism 22. Operatively connected, the ratio of the feed amount of the differential feed dog member 4 to the feed amount of the main feed dog member 2 can be switched steplesslyInSince it is configured, the structure of the differential feeder 6 is simple and small, and the manufacturing cost can be significantly reduced.
[0048]
  The differential feed coupling mechanism 22 is pivotally connected to the main feed arm 14 that transmits the feed driving force to the main feed dog member 2 at the middle in the height direction and is operatively connected to the differential feed dog member 4. The lower half includes a link member 30 having an arcuate engagement portion 30a and includes an engagement pin member 42 engaged with the engagement portion 30a. The height direction of the engagement pin member 42 at the engagement portion 30a Since the switching operation mechanism 31 for steplessly switching the ratio of the feed amount of the differential feed coupling mechanism 22 by changing the position is provided, the ratio of the feed amount is set according to the stretchability of the cloth to be sewn. It becomes possible to easily set to an appropriate ratio.
[0049]
  Since the switching operation mechanism 31 includes the dial member 40 provided in the free bed portion 83 of the sewing machine M, and the conversion mechanism 45 that converts the rotation operation of the dial member 40 into the movement of the engagement pin member 42 in the height direction. By rotating the dial member 40, the engaging pin member 42 is moved in the height direction via the conversion mechanism 45, and the height position of the engaging pin member 42 in the engaging portion 30a is easily changed. It becomes possible.
  In the above-described embodiment, the differential feed ratio is continuously rotated by the dial member 40 that can be rotated. However, a slide lever may be used as long as it is a member that can be continuously operated. If the configuration is set in a stepless manner, it is easy to adapt a good differential ratio to the stretch of the fabric as compared to a multi-step setting with a plurality of push buttons.
[0050]
【The invention's effect】
  According to the differential feeding device of the sewing machine of claim 1,A projection-like engaging portion of the switching operation mechanism is pivotally attached to the main feed member about one axis in a direction intersecting the moving direction of the main feed member, and sandwiched between the pivot attachment portions. A link member having an arcuate engaging portion that engages with each other so as to be relatively movable, and a differential feed dog member that is fixed to the differential feed dog member, and the differential feed dog member is integrated with the main feed dog member. And a connecting member connected to the main feed dog member so as to be movable relative to the main feed dog in a predetermined stroke relative to the main feed dog member. Since it was directly connected by the connecting means,According to the stretchability of the fabric to be sewn, the ratio of the feed amount is set to an appropriate ratio, and the fabric feed can be executed so that the stretch fabric does not stretch.By simplifying the connection structure from the link member to the differential feed dog memberThe structure of the differential feeding device is simple and small, and the manufacturing cost is significantly reduced.
[0051]
  According to the differential feeding device of the sewing machine of claim 2,Since the movable connecting means is constituted by a pin provided on one of the other side portion of the link member and the connecting member and a groove-like engaging portion provided on the other for movably engaging the pin. The same effect is produced.
[0052]
[Brief description of the drawings]
FIG. 1 shows an embodiment of the present invention.InIt is a perspective view of the lock sewing machine which concerns.
FIG. 2 is a front view of the lock sewing machine.
FIG. 3 is a left side view of the lock sewing machine.
FIG. 4 is a left side perspective view of the lock sewing machine.
FIG. 5 is a front perspective view of the lock sewing machine.
FIG. 6 is a left side view of the main part inside the lock sewing machine.
FIG. 7 is a right side view of an essential part inside the lock sewing machine.
FIG. 8 is a plan view of an essential part inside the lock sewing machine.
FIG. 9 is a front view of an essential part inside the lock sewing machine.
FIG. 10 is an operation explanatory diagram of the differential feeding device.
FIG. 11 is an operation explanatory diagram of the differential feeding device.
FIG. 12 is an operation explanatory diagram of the differential feeding device.
FIG. 13 is an operation explanatory diagram of the differential feeding device.
FIG. 14 is a diagram showing feed amounts of a main feed dog member and a differential feed dog member.
FIG. 15 is a view showing a height position adjusting mechanism (first and second adjusting mechanisms).
FIG. 16 is an operation explanatory diagram of the vertical drive mechanism.
FIG. 17 is an operation explanatory diagram of the vertical drive mechanism.
FIG. 18 is an operation explanatory diagram of the first adjustment mechanism.
FIG. 19 is an operation explanatory diagram of the first adjustment mechanism.
20 is a cross-sectional view taken along line XX-XX in FIG.
FIG. 21 is an operation explanatory diagram of the second adjustment mechanism.
FIG. 22 is an operation explanatory diagram of the second adjustment mechanism.
[Explanation of symbols]
M lock sewing machine
1 Main feed dog
2 Main feed dog members
3 Differential feed dog
4 Differential feed dog members
5 Front-rear drive mechanism
6 Differential feeder
7 Vertical drive mechanism
8 First adjustment mechanism
9 Second adjustment mechanism
10 Drive shaft
11 Longitudinal drive cam
12 Front / rear driving force transmission member
13 pivot axis
14 Main feed arm
16 Pin member
20 Slide mechanism
21 Compression coil spring
26                Connecting bracket
30 Link member
30a Engagement part
30b              Groove engaging part
31 Switching operation mechanism
35                Shaft member
36                pin
42 engaging pin member
50 Vertical drive cam
51 Vertical drive force transmission member
52 Swing link member
54 Forked cam follower
55 Movable blade
57 Shaft (pin member)
60 Oscillating transmission member
61 pivot pin
62 Transmitter
63 Slotted hole
65 Eccentric mechanism
66 Eccentric pin
84 Needle plate

Claims

A main feed dog member having a main feed dog that feeds a cloth to be sewn on the needle plate; a differential feed dog member having a differential feed dog that feeds the cloth at a position in front of the main feed tooth; and A main feed member for transmitting a feed driving force to the main feed dog member, and a switching operation mechanism for enabling stepless switching of the ratio of the feed amount of the differential feed dog member to the feed amount of the main feed dog member; In the sewing machine differential feed device with
It is pivotally attached to the main feed member about a single axis in a direction intersecting with the moving direction of the main feed member, and the projection-like engagement of the switching operation mechanism on one side of the pivot attachment portion. A link member having an arcuate engagement portion that engages the portion so as to be relatively movable;
The differential feed dog member is fixed to the differential feed dog member, and the differential feed dog member is moved up and down integrally with the main feed dog member, and is connected to the main feed dog member so as to be relatively movable in a cloth feed direction by a predetermined stroke. A connecting member,
A differential feeding device for a sewing machine, wherein the other side portion and the connecting member are directly connected by a movable connecting means with the pivoting portion of the link member interposed therebetween .

The movable connecting means is constituted by a pin provided on one of the other side portion of the link member and the connecting member, and a groove-like engaging portion provided on the other side and movably engaged with the pin. The differential feeding device for a sewing machine according to claim 1, wherein: