JP2009195382A - Thread cutter of sewing machine - Google Patents
Thread cutter of sewing machine Download PDFInfo
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- JP2009195382A JP2009195382A JP2008038739A JP2008038739A JP2009195382A JP 2009195382 A JP2009195382 A JP 2009195382A JP 2008038739 A JP2008038739 A JP 2008038739A JP 2008038739 A JP2008038739 A JP 2008038739A JP 2009195382 A JP2009195382 A JP 2009195382A
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Abstract
Description
本発明は、ミシンの糸切り装置に関し、特に回転釜の外釜と剣先により形成された上糸ループに可動刃の尖端部が係合開始した後糸切り前に、回転釜から延びる下糸を所定量だけ繰出すように構成したものに関する。 The present invention relates to a thread trimming device for a sewing machine, and more particularly to a lower thread extending from a rotary hook before thread trimming after the tip of a movable blade starts engaging with an upper thread loop formed by an outer hook and a sword tip of a rotary hook. The present invention relates to an arrangement configured to feed a predetermined amount.
従来、針板とその下側に配設された回転釜との間に、可動刃（移動刃）と固定刃とを有する糸切り装置を設けたミシンがある。縫製終了時に、縫針の目孔から加工布を通過して延びる上糸と、回転釜から延びる下糸とを糸切り装置により自動的に切断できるようになっている。糸切り装置として、可動刃を直線状に往復移動させる直線移動タイプが実用化されているが、これ以外にも、可動刃を水平に往復回動させる回動タイプのものが開示されている。 Conventionally, there is a sewing machine provided with a thread trimming device having a movable blade (moving blade) and a fixed blade between a needle plate and a rotary hook disposed below the needle plate. At the end of sewing, the upper thread extending through the work cloth from the stitch hole of the sewing needle and the lower thread extending from the rotary hook can be automatically cut by the thread trimming device. As a thread trimming device, a linear movement type in which a movable blade is reciprocated linearly has been put to practical use. In addition to this, a rotary type in which the movable blade is horizontally reciprocated is disclosed.
回動タイプの糸切り装置として、例えば、特許文献１に記載のミシンの上糸挟持機構においては、針板の下面に、刃部を有する固定刃が螺子止めされるとともに、刃部を有する可動刃が支持ピンにより回動可能に支持され、糸切り連竿の先端部に可動刃が水平に往復回動可能に連結されている。糸切り時に、糸切りソレノイドの駆動により糸切り駆動系を介して糸切り連竿が前方に移動することにより、可動刃と固定刃との協働で上糸と下糸を切断する。
通常、回転釜の外釜の回転により、加工布を挿通した縫針の目孔から延びる上糸の上糸ループが剣先によって捕捉され、剣先が回転釜の中釜の周囲を周回することにより、縫針の目孔から延びる上糸ループとボビンからの下糸とが交絡され、この状態で、天秤により上糸ループを引き締めて縫目を形成した後、糸切り装置により上糸と下糸を切断する。
この場合、上糸ループを引き締める際に下糸も上方に引き上げられるため、ボビンから延びる下糸が張った状態になる。
Normally, when the outer hook of the rotary hook rotates, the upper thread loop of the upper thread extending from the needle hole of the sewing needle inserted through the work cloth is caught by the sword, and the needle moves around the inner hook of the rotary hook. The upper thread loop extending from the eye hole and the lower thread from the bobbin are entangled. In this state, the upper thread loop is tightened by a balance to form a stitch, and then the upper thread and the lower thread are cut by a thread trimming device. .
In this case, when the upper thread loop is tightened, the lower thread is also pulled upward, so that the lower thread extending from the bobbin is stretched.
特許文献１に記載の糸切り装置では、糸切り時に可動刃が高速で回動するため、下糸を切断する際に下糸の張力がボビンに伝達され下糸の張力が瞬間的に高い張力になる。
その結果、ボビンが空転し下糸がボビンから繰出した状態になるので、縫製再開後の縫い調子が不安定になるという虞がある。
In the thread trimming apparatus described in Patent Document 1, since the movable blade rotates at high speed during thread trimming, the tension of the lower thread is transmitted to the bobbin when the lower thread is cut, and the tension of the lower thread is instantaneously high. become.
As a result, the bobbin is idling and the lower thread is fed from the bobbin, so that there is a possibility that the sewing condition after resuming the sewing becomes unstable.
本発明の目的は、糸切り時に下糸を切断する際、下糸の張力がボビンに伝達されないようにして、ボビンの空転を防止することができるミシンの糸切り装置を提供することである。 An object of the present invention is to provide a thread trimming device for a sewing machine that prevents bobbin slipping by preventing tension of the lower thread from being transmitted to the bobbin when cutting the lower thread during thread trimming.
請求項１のミシンの糸切り装置は、針板の下側で主軸による縫針の上下動と調時して回転する外釜を有する回転釜を有するミシンに、前記針板の下面近傍に設けられた固定刃と水平に往復回動可能な可動刃とを有する糸切り機構と、前記可動刃を回動駆動する糸切り駆動機構とを設けた糸切り装置において、前記可動刃がその待機位置から回動開始後、前記縫針の目孔から加工布を通過して延びた上糸に前記回転釜の外釜と剣先により形成された上糸ループに、前記可動刃の尖端部が係合開始した後糸切り前に、回転釜から延びる下糸を所定量だけ繰出す下糸繰出し機構を設けたことを特徴とする。 The thread trimming device for a sewing machine according to claim 1 is provided in the vicinity of the lower surface of the needle plate in a sewing machine having a rotary hook having an outer hook that rotates in synchronization with the vertical movement of the sewing needle by the main shaft below the needle plate. In a thread trimmer provided with a thread trimming mechanism having a fixed blade and a movable blade that is horizontally reciprocally movable, and a thread trimming drive mechanism that rotationally drives the movable blade, the movable blade is moved from its standby position. After the rotation started, the tip of the movable blade started to engage with the upper thread loop formed by the outer hook of the rotary hook and the sword tip on the upper thread that passed through the work cloth from the eye of the sewing needle. A lower thread feeding mechanism is provided that feeds a predetermined amount of lower thread extending from the rotary hook before rear thread trimming.
このミシンの糸切り装置では、縫製終了時に可動刃がその待機位置から回動開始後、縫針の目孔から加工布を通過して延びた上糸に回転釜の外釜と剣先により形成された上糸ループに、可動刃の尖端部が係合開始した後糸切り前に、下糸繰出し機構により回転釜から延びる下糸が所定量だけ繰出される。その結果、糸切り前に下糸に対して適度な弛みを持たせることができ、糸切り時に下糸を切断する際に下糸の張力がボビンに伝達されないため、ボビンの空転を防止することができる。 In this sewing machine thread trimming device, when the movable blade starts rotating from its standby position at the end of sewing, an upper thread extending through the work cloth from the eye of the sewing needle is formed by the outer hook of the rotary hook and the sword tip. The lower thread extending from the rotary hook is fed by a predetermined amount by the lower thread feeding mechanism after the tip of the movable blade starts engaging the upper thread loop and before thread trimming. As a result, the bobbin thread can be moderately slackened before thread trimming, and the bobbin thread tension is not transmitted to the bobbin when cutting the bobbin thread during thread trimming, preventing bobbin slipping. Can do.
請求項２のミシンの糸切り装置は、請求項１の発明において、前記下糸繰出し機構は、前記可動刃の回動領域の下側近傍において水平に往復回動可能な下糸繰出しレバーを備え、前記下糸繰出しレバーが下糸に係合した状態で前記可動刃の待機位置の方向に回動することで、前記回転釜内のボビンから下糸を繰出すことを特徴とする。 A thread trimming device for a sewing machine according to a second aspect of the present invention is the sewing machine according to the first aspect, wherein the lower thread feeding mechanism includes a lower thread feeding lever that can reciprocate horizontally in the vicinity of the lower side of the rotating area of the movable blade. The bobbin thread is fed out from the bobbin in the rotary hook by rotating the lower thread feeding lever toward the standby position of the movable blade in a state where the lower thread feeding lever is engaged with the lower thread.
請求項３のミシンの糸切り装置は、請求項２の発明において、前記下糸繰出し機構は、前記糸切り駆動機構により糸切り動作と連動して駆動されることを特徴とする。 A thread trimming device for a sewing machine according to a third aspect is the invention according to the second aspect, wherein the lower thread feeding mechanism is driven by the thread trimming drive mechanism in conjunction with a thread trimming operation.
請求項４のミシンの糸切り装置は、請求項３の発明において、前記下糸繰出し機構は、前記下糸繰出しレバーと、この下糸繰出しレバーの一端部を鉛直軸心回りに回動可能に連結する連結部と、この下糸繰出しレバーの長さ方向途中部を前記可動刃に連動連結するリンク機構とを有することを特徴とする。 According to a fourth aspect of the present invention, there is provided the thread trimming device according to the third aspect, wherein the lower thread feeding mechanism is configured such that the lower thread feeding lever and one end of the lower thread feeding lever can be rotated about a vertical axis. It has a connecting portion to be connected and a link mechanism for interlockingly connecting the middle portion in the length direction of the lower thread feeding lever to the movable blade.
請求項５のミシンの糸切り装置は、請求項１〜４の何れかの発明において、前記下糸繰出し機構は、前記可動刃がその最大回動位置へ回動する前に下糸に係合開始し且つ前記可動刃が前記最大回動位置に達したときに下糸を最大限繰出すことを特徴とする。 A thread trimming device for a sewing machine according to a fifth aspect of the present invention is the sewing machine according to any one of the first to fourth aspects, wherein the lower thread feeding mechanism is engaged with the lower thread before the movable blade rotates to its maximum rotational position. The bobbin thread is fed out to the maximum when the movable blade starts and reaches the maximum rotation position.
請求項６のミシンの糸切り装置は、請求項２〜５の何れかの発明において、前記可動刃は、前記上糸ループの加工布から延びる側を捕捉する糸捕捉部を有し、前記下糸繰出しレバーは、前記上糸ループの加工布から延びる側が前記可動刃の糸捕捉部に到達したときに下糸と係合することを特徴とする。 A thread trimming device for a sewing machine according to a sixth aspect of the present invention is the sewing machine according to any one of the second to fifth aspects, wherein the movable blade has a thread catching section that captures a side extending from the work cloth of the upper thread loop, and the lower The yarn feeding lever is engaged with the lower yarn when the side of the upper yarn loop extending from the work cloth reaches the yarn catching portion of the movable blade.
請求項１の発明によれば、可動刃がその待機位置から回動開始後、縫針の目孔から加工布を通過して延びた上糸に回転釜の外釜と剣先により形成された上糸ループに、可動刃の尖端部が係合開始した後糸切り前に、回転釜から延びる下糸を所定量だけ繰出す下糸繰出し機構を設けたので、糸切り前に下糸に対して適度な弛みを持たせることができる。
これにより、糸切り時に下糸を切断する際に下糸の張力がボビンに伝達されないため、ボビンの空転を防止することができ、縫製再開後の縫い調子が不安定にならない。
According to the first aspect of the present invention, after the movable blade starts rotating from its standby position, the upper thread formed by the outer hook of the rotary hook and the sword tip is formed on the upper thread extending through the work cloth from the eye of the sewing needle. The loop is provided with a lower thread feeding mechanism that feeds a predetermined amount of lower thread extending from the rotary hook before thread trimming after the tip of the movable blade starts to be engaged. Can have a slack.
As a result, since the lower thread tension is not transmitted to the bobbin when the lower thread is cut during thread trimming, the bobbin can be prevented from idling, and the sewing tone after resuming sewing does not become unstable.
請求項２の発明によれば、下糸繰出し機構は、可動刃の回動領域の下側近傍において水平に往復回動可能な下糸繰出しレバーを備え、下糸繰出しレバーが下糸に係合した状態で可動刃の待機位置の方向に回動することで、回転釜内のボビンから下糸を繰出すので、下糸を可動刃の待機位置の方向に繰出すことができる。それ故、糸切り時に可動刃の回動により下糸を確実に捕捉して切断することができる。 According to the second aspect of the present invention, the lower thread feeding mechanism includes the lower thread feeding lever that can be horizontally reciprocated in the vicinity of the lower side of the rotating area of the movable blade, and the lower thread feeding lever is engaged with the lower thread. In this state, the lower thread is fed out from the bobbin in the rotary hook by rotating in the direction of the standby position of the movable blade, so that the lower thread can be extended in the direction of the standby position of the movable blade. Therefore, the lower thread can be reliably captured and cut by turning the movable blade during thread trimming.
請求項３の発明によれば、下糸繰出し機構は、糸切り駆動機構により糸切り動作と連動して駆動されるので、可動刃の回動に連動して下糸繰出しレバーを回動することができ、糸切り前に下糸を確実に繰出すことができる。 According to the invention of claim 3, since the lower thread feeding mechanism is driven in conjunction with the thread trimming operation by the thread trimming drive mechanism, the lower thread feeding lever is rotated in conjunction with the rotation of the movable blade. The lower thread can be unwound reliably before thread trimming.
請求項４の発明によれば、下糸繰出し機構は、下糸繰出しレバーと、この下糸繰出しレバーの一端部を鉛直軸心回りに回動可能に連結する連結部と、この下糸繰出しレバーの長さ方向途中部を可動刃に連動連結するリンク機構とを有するので、下糸繰出し機構を簡単な構成で実現することができる。 According to the invention of claim 4, the lower thread feeding mechanism includes a lower thread feeding lever, a connecting portion that rotatably connects one end portion of the lower thread feeding lever about the vertical axis, and the lower thread feeding lever. The lower thread feeding mechanism can be realized with a simple configuration.
請求項５の発明によれば、下糸繰出し機構は、可動刃がその最大回動位置へ回動する前に下糸に係合開始し且つ可動刃が最大回動位置に達したときに下糸を最大限繰出すので、下糸繰出しレバーによる上糸の挟み込みを防止しつつ、下糸のみを確実に繰出すことができる。 According to the invention of claim 5, the lower thread feeding mechanism starts to engage with the lower thread before the movable blade rotates to its maximum rotation position, and lowers when the movable blade reaches the maximum rotation position. Since the yarn is fed to the maximum extent, it is possible to reliably feed only the lower yarn while preventing the upper yarn from being caught by the lower yarn feeding lever.
請求項６の発明によれば、可動刃は、上糸ループの加工布から延びる側を捕捉する糸捕捉部を有し、下糸繰出しレバーは、上糸ループの加工布から延びる側が可動刃の糸捕捉部に到達したときに下糸と係合するので、下糸繰出しレバーによる上糸の挟み込みを防止しつつ、下糸のみを確実に繰出すことができる。 According to the invention of claim 6, the movable blade has a yarn catching portion that catches the side of the upper thread loop extending from the work cloth, and the lower thread feeding lever has a side that extends from the work cloth of the upper thread loop. Since the lower thread engages with the lower thread when reaching the thread catching section, it is possible to reliably feed only the lower thread while preventing the upper thread from being caught by the lower thread feeding lever.
以下、本発明を実施する為の最良の形態について説明する。 Hereinafter, the best mode for carrying out the present invention will be described.
以下、本発明の実施例について図面に基づいて説明する。
図１〜図４に示すように、ミシンＭは、着脱可能に固定される針板８を有するベッド部１と、ベッド部１の後端部から上方に立設する脚柱部２と、脚柱部２の上端部からベッド部１と対向するように前方へ延びるアーム部３等から構成されている。
Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIGS. 1 to 4, the sewing machine M includes a bed portion 1 having a needle plate 8 that is detachably fixed, a pedestal portion 2 erected upward from the rear end portion of the bed portion 1, legs The arm portion 3 extends forward from the upper end portion of the column portion 2 so as to face the bed portion 1.
脚柱部２とアーム部３には、ミシンモータ（図示略）と、このミシンモータの駆動力をミシン主軸４を介して針棒５に伝達して上下駆動する針棒上下駆動機構（図示略）、上糸１６（図７−１参照）を引き上げる天秤（図示略）を駆動する天秤駆動機構（図示略）等が設けられている。脚柱部２とベッド部１には、後述する糸切り機構１２の可動刃１９を揺動駆動する揺動力を発生する糸切り駆動機構１３が設けられている。 The pedestal 2 and the arm 3 are provided with a sewing machine motor (not shown) and a needle bar vertical drive mechanism (not shown) that transmits the driving force of the sewing machine motor to the needle bar 5 via the sewing machine main shaft 4 and drives it up and down. ), A balance driving mechanism (not shown) for driving a balance (not shown) for pulling up the upper thread 16 (see FIG. 7-1) and the like. The pedestal 2 and the bed 1 are provided with a thread trimming drive mechanism 13 that generates a swinging force that swings and drives a movable blade 19 of a thread trimming mechanism 12 described later.
ベッド部１には、針穴８ａが形成された針板８と、縫針６の上下動と調時して縫目を形成する垂直回転釜（以下、単に回転釜という）９と、この回転釜９に回転駆動力を伝達する下軸７と、糸切り機構１２と、糸切り駆動機構１３のうちの糸切りリンク機構１５と、下糸繰出し機構４２等が設けられている。 The bed portion 1 includes a needle plate 8 having a needle hole 8a, a vertical rotary hook (hereinafter simply referred to as a rotary hook) 9 that forms seams when the sewing needle 6 is moved up and down, and the rotary hook. A lower shaft 7 for transmitting a rotational driving force to 9, a thread trimming mechanism 12, a thread trimming link mechanism 15 of the thread trimming driving mechanism 13, a lower thread feeding mechanism 42, and the like are provided.
次に、針板８の下側に配設された回転釜９について説明する。
図２、図７−１に示すように、回転釜９は、ベッド部１に配設された下軸７により回転可能な外釜５１と、この外釜５１に前側から嵌まり込んで外釜５１に回転可能に支持される中釜５２と、この中釜５２に装着されるボビンケース５３とで構成されている。
Next, the rotary hook 9 disposed below the needle plate 8 will be described.
As shown in FIGS. 2 and 7-1, the rotary hook 9 includes an outer hook 51 that can be rotated by the lower shaft 7 disposed in the bed portion 1, and the outer hook 51 fitted into the outer hook 51 from the front side. An inner hook 52 that is rotatably supported by 51 and a bobbin case 53 attached to the inner hook 52 are configured.
外釜５１は、ミシン主軸４と同期して回転する下軸７の前端部にカップリング５７を介して連結されている。ミシンモータの回転力がミシン主軸４から下軸７に伝達され、外釜５１は下軸７と共にミシン主軸４による縫針６の上下動と調時して正面視にて時計回りに回転する。このとき、外釜５１に時計回りの回転方向に向けて突起状に一体形成された剣先５１ａも、時計回りに回転する。 The outer shuttle 51 is connected via a coupling 57 to the front end of the lower shaft 7 that rotates in synchronization with the sewing machine main shaft 4. The rotational force of the sewing machine motor is transmitted from the sewing machine main shaft 4 to the lower shaft 7, and the outer shuttle 51 rotates with the lower shaft 7 when the sewing needle 6 moves up and down by the sewing machine main shaft 4 and rotates clockwise in front view. At this time, the sword tip 51a formed integrally with the outer hook 51 in a protruding shape in the clockwise rotation direction also rotates clockwise.
ボビンケース５３は前面が塞がれた筒体であり、このボビンケース５３には、下糸１７が巻装された下糸ボビン（図示略）が収納されている。下軸７の回転力が回転釜９に伝達されると、外釜５１が縫針６の上下動に調時して、中釜５２とボビンケース５３を回り止めした状態で、正面視にて時計回りに回転する。 The bobbin case 53 is a cylindrical body whose front is closed, and the bobbin case 53 stores a lower thread bobbin (not shown) around which the lower thread 17 is wound. When the rotational force of the lower shaft 7 is transmitted to the rotary hook 9, the outer hook 51 adjusts the vertical movement of the sewing needle 6, and the center hook 52 and the bobbin case 53 are prevented from rotating. Rotate around.
外釜５１の回転により、加工布Ｗを挿通した縫針６の目孔６ａから延びる上糸１６の上糸ループ１６ａが剣先５１ａによって捕捉され、剣先５１ａが中釜５２の周囲を周回することにより、縫針６の目孔６ａから延びる上糸ループ１６ａと下糸ボビンからの下糸１７とが交絡され、天秤により上糸ループ１６ａが引き締められて縫目が形成される。 By rotating the outer hook 51, the upper thread loop 16a of the upper thread 16 extending from the eye hole 6a of the sewing needle 6 through which the work cloth W is inserted is captured by the sword tip 51a, and the sword tip 51a circulates around the inner hook 52. The upper thread loop 16a extending from the stitch hole 6a of the sewing needle 6 and the lower thread 17 from the lower thread bobbin are entangled, and the upper thread loop 16a is tightened by a balance to form a stitch.
ボビンケース５３の前面の上部左側に下糸出口５３ａの下端部が固着されており、ボビンケース５３の出口５４ａから引き出された下糸１７は、下糸出口５３ａの案内穴を前側から後側に通され、針板８の針穴８ａを経て加工布Ｗに連なっている。 The lower end of the lower thread outlet 53a is fixed to the upper left side of the front surface of the bobbin case 53, and the lower thread 17 drawn out from the outlet 54a of the bobbin case 53 moves the guide hole of the lower thread outlet 53a from the front side to the rear side. Through the needle hole 8 a of the needle plate 8, the work cloth W is continued.
次に、糸切り装置１１について説明する。
糸切り装置１１は、糸切り機構１２と、糸切り駆動機構１３と、下糸繰出し機構４２とを有する。先ず、糸切り機構１２について説明する。
図４，図７−２に示すように、糸切り機構１２は、針板８の下面近傍に設けられた固定刃１８と、水平に往復回動可能な可動刃１９とを有する。
Next, the thread trimming device 11 will be described.
The thread trimming device 11 includes a thread trimming mechanism 12, a thread trimming drive mechanism 13, and a lower thread feeding mechanism 42. First, the thread trimming mechanism 12 will be described.
As shown in FIGS. 4 and 7-2, the thread trimming mechanism 12 includes a fixed blade 18 provided near the lower surface of the needle plate 8 and a movable blade 19 that can be horizontally reciprocated.
図５に示すように、可動刃１９は、糸さばき部１９ａ（尖端部）、貫通穴１９ｆの端部の刃部１９ｂ、糸案内部１９ｃ、糸係合部１９ｄ及び上糸ループ１６ａの加工布Ｗから延びる側を捕捉する糸捕捉部１９ｅとで構成されている。糸さばき部１９ａは、平面視にて鋭角状に形成されている。糸案内部１９ｃは、糸さばき部１９ａに連なり、平面視にて円弧状に形成されている。糸捕捉部１９ｅは、糸案内部１９ｃの中間よりも後方において開口１９ｉ側に張出し、開口１９ｉが形成された部分と糸案内部１９ｃとの高さよりも低く略三角形の溝状に形成されている。図５において、開口１９ｉから左下側に張出した部分に、下向き（紙面裏側）のピン２２が設けられている。開口１９ｉから右下側に張出した部分に、上向き（紙面表側）のピン４７が設けられている。 As shown in FIG. 5, the movable blade 19 includes a work cloth for a yarn separating portion 19a (pointed end portion), a blade portion 19b at the end of the through hole 19f, a yarn guiding portion 19c, a yarn engaging portion 19d, and an upper yarn loop 16a. And a yarn catching portion 19e for catching the side extending from W. The yarn separating portion 19a is formed in an acute angle shape in plan view. The yarn guide portion 19c is connected to the yarn separating portion 19a and is formed in an arc shape in plan view. The yarn catching portion 19e projects to the opening 19i side behind the middle of the yarn guide portion 19c, and is formed in a substantially triangular groove shape that is lower than the height between the portion where the opening 19i is formed and the yarn guide portion 19c. . In FIG. 5, a pin 22 facing downward (back side of the drawing) is provided at a portion protruding from the opening 19 i to the lower left side. An upward-facing (paper surface side) pin 47 is provided at a portion protruding from the opening 19 i to the lower right side.
針板８の下側に、平面視略Ｌ字形状の固定刃１８がこの基端部において螺子２０により固定されている。固定刃１８は、弾性変形可能に構成され、前方の基端部から略水平状で且つ左斜め後方に延設され、後端部で下方に曲げ形成されて刃部１８ａが形成されている。この固定刃１８の下側に位置するように可動刃１９が配設され、開口１９ｉを介して段付きボルト（鉛直支軸）２１により、水平に往復回動可能に支持されている。 A fixed blade 18 having a substantially L shape in plan view is fixed to the lower side of the needle plate 8 by a screw 20 at the base end portion. The fixed blade 18 is configured to be elastically deformable, extends substantially horizontally from the front base end portion and obliquely left rearward, and is bent downward at the rear end portion to form a blade portion 18a. A movable blade 19 is disposed so as to be positioned below the fixed blade 18, and is supported by a stepped bolt (vertical support shaft) 21 through an opening 19i so as to be horizontally reciprocally rotatable.
段付きボルト２１は、下軸７よりも右側（上糸ループ１６ａがボビンケース５３に掛かりはじめる側）で且つ針穴８ａよりも後側で針板８に固着されている。可動刃１９の駆動部（図７−２において後端部）には、後述する糸切り駆動機構１３の糸切りリンク機構１５から延びる第３リンク３７の先端部がピン２２により回動可能に連結されている。可動刃１９は、図４、図７−１、図７−２、図１２−１、図１２−２に示す待機位置と、この待機位置から図１０−１、図１０−２に示す最大回動位置とに亙って、水平に往復回動可能に構成されている。 The stepped bolt 21 is fixed to the needle plate 8 on the right side of the lower shaft 7 (the side where the upper thread loop 16a starts to be hooked on the bobbin case 53) and on the rear side of the needle hole 8a. A distal end portion of a third link 37 extending from a thread trimming link mechanism 15 of a thread trimming drive mechanism 13 to be described later is rotatably connected by a pin 22 to a driving portion of the movable blade 19 (rear end portion in FIG. 7-2). Has been. The movable blade 19 has a standby position shown in FIGS. 4, 7-1, 7-2, 12-1, and 12-2 and a maximum rotation shown in FIGS. 10-1 and 10-2 from this standby position. It is configured to be able to reciprocate horizontally over the moving position.
可動刃１９が待機位置に回動復帰するとき、可動刃１９の刃部１９ｂと固定刃１８の刃部１８ａとの協働により、下糸１７と上糸ループ１６ａの加工布Ｗ側の上糸１６とが同時に切断される。上糸ループ１６ａは、縫針６の目孔６ａから延び、加工布Ｗに至る上糸を示す。 When the movable blade 19 returns to the standby position, the upper thread of the lower thread 17 and the upper thread loop 16a on the work cloth W side is cooperated by the blade part 19b of the movable blade 19 and the blade part 18a of the fixed blade 18. 16 are cut simultaneously. The upper thread loop 16 a indicates an upper thread extending from the eye hole 6 a of the sewing needle 6 and reaching the work cloth W.
次に、可動刃１９を回動駆動する糸切り駆動機構１３について説明する。
図１〜図４に示すように、糸切り駆動機構１３は、可動刃１９に対する揺動力を発生させる揺動力発生機構１４と、この揺動力発生機構１４により発生した揺動力を可動刃１９に伝達する糸切りリンク機構１５とを有する。揺動力発生機構１４は、ミシン主軸４に設けられた糸切りカム板２５と、駆動レバー２６と、糸切りソレノイド２７等を有する。
Next, the thread trimming drive mechanism 13 that rotationally drives the movable blade 19 will be described.
As shown in FIGS. 1 to 4, the thread trimming drive mechanism 13 transmits a swinging force generation mechanism 14 that generates a swinging force to the movable blade 19 and the swinging force generated by the swinging force generation mechanism 14 to the movable blade 19. And a thread trimming link mechanism 15. The swinging force generating mechanism 14 includes a thread trimming cam plate 25 provided on the sewing machine main shaft 4, a drive lever 26, a thread trimming solenoid 27, and the like.
ミシン主軸４の後端近傍部に、糸切り動作を発生させる溝カム２５ａが形成された糸切りカム板２５が固着されている。糸切りカム板２５の直前に左右向きの駆動レバー２６が配設されている。駆動レバー２６は左端近傍部において、前後方向向きの案内軸２８に固着されている。この案内軸２８は図示しないフレーム等の支持部材で前後方向に往復移動可能に支持されている。 A thread trimming cam plate 25 having a groove cam 25a for generating a thread trimming operation is fixed to the vicinity of the rear end of the sewing machine main shaft 4. A left and right drive lever 26 is disposed immediately before the thread trimming cam plate 25. The drive lever 26 is fixed to a guide shaft 28 in the front-rear direction near the left end. The guide shaft 28 is supported by a support member such as a frame (not shown) so as to be reciprocally movable in the front-rear direction.
図６に示すように、糸切りカム板２５に形成された溝カム２５ａには、Ａで示す第１カム部と、Ｂで示す第２カム部と、Ｃで示す第３カム部と、Ｄで示す第４カム部と、Ｅで示す第５カム部と、Ｆで示す第６カム部とが連続して形成されている。第１カム部Ａと、第３カム部Ｃと、第５カム部Ｅと、第６カム部Ｆとは、可動刃１９を揺動させるカム部であり、第２カム部Ｂと、第４カム部Ｄとは、可動刃１９を揺動させないカム部である。
即ち、糸切りカム板２５には、可動刃１９の回動速度や動作タイミングが設定されている。
As shown in FIG. 6, the groove cam 25a formed on the thread trimming cam plate 25 includes a first cam portion indicated by A, a second cam portion indicated by B, a third cam portion indicated by C, and D The 4th cam part shown by E, the 5th cam part shown by E, and the 6th cam part shown by F are formed continuously. The 1st cam part A, the 3rd cam part C, the 5th cam part E, and the 6th cam part F are cam parts which rock the movable blade 19, and the 2nd cam part B and 4th The cam portion D is a cam portion that does not swing the movable blade 19.
That is, the rotation speed and operation timing of the movable blade 19 are set in the thread trimming cam plate 25.
図１〜図４に示すように、駆動レバー２６の右端部に、後述する糸切りリンク機構１５の第１リンク３５の上端部が連結されている。駆動レバー２６の右端近傍部に、糸切りカム板２５の溝カム２５ａに係合可能なコロ部材２９が設けられている。駆動レバー２６は案内軸２８と共に、コロ部材２９が溝カム２５ａに入り込んで係合する後側の係合位置（図３において２点鎖線で示す位置）と、この係合位置から所定距離だけ前方であって、コロ部材２９が溝カム２５ａから前側に外れる非係合位置（図３において実線で示す位置）とに亙って移動可能になっている。 As shown in FIGS. 1-4, the upper end part of the 1st link 35 of the thread trimming link mechanism 15 mentioned later is connected with the right end part of the drive lever 26. As shown in FIG. A roller member 29 that can be engaged with the groove cam 25 a of the thread trimming cam plate 25 is provided in the vicinity of the right end of the drive lever 26. The drive lever 26, together with the guide shaft 28, is engaged at a rear engagement position (a position indicated by a two-dot chain line in FIG. 3) where the roller member 29 enters and engages the groove cam 25a, and a predetermined distance from the engagement position. In this case, the roller member 29 is movable over the disengagement position (position indicated by the solid line in FIG. 3) where the roller member 29 is disengaged from the groove cam 25a to the front side.
但し、この駆動レバー２６は、圧縮コイルバネ３０のバネ力により通常前側の非係合位置に位置している。駆動レバー２６の左端部の前側に、縦向きの揺動軸３２により水平面で回動可能な回動板３１が配設されている。糸切りソレノイド２７が回動板３１を回動可能に操作する。 However, the drive lever 26 is normally located at the front non-engagement position by the spring force of the compression coil spring 30. On the front side of the left end portion of the drive lever 26, a rotating plate 31 that can be rotated in a horizontal plane by a vertical swing shaft 32 is disposed. The thread trimming solenoid 27 operates the rotating plate 31 to be rotatable.
駆動レバー２６の右端近傍部には、前方に曲げ加工された当接片２６ａが形成されている。この当接片２６ａは図示外の高さ位置調節螺子に下側から当接するようになっており、駆動レバー２６の右端部の高さ位置、つまり、第１リンク３５の基準高さ位置が位置決めされると共に、糸切り動作を行う際にコロ部材２９が溝カム２５ａに確実に係合できる高さ位置に調節されている。 A contact piece 26 a bent forward is formed in the vicinity of the right end of the drive lever 26. The contact piece 26a comes into contact with a height position adjusting screw (not shown) from below, and the height position of the right end portion of the drive lever 26, that is, the reference height position of the first link 35 is positioned. At the same time, the roller member 29 is adjusted to a height position where the roller member 29 can be reliably engaged with the groove cam 25a when the thread trimming operation is performed.
縫製中において糸切りソレノイド２７に通電されない場合は、案内軸２８と駆動レバー２６は、圧縮コイルバネ３０のバネ力により図３において実線で示す前側の非係合位置に待機している。この場合、糸切りカム板２５はミシン主軸４と同時に回転しているが、コロ部材２９が糸切りカム板２５の溝カム２５ａに係合しないため、駆動レバー２６が揺動せず、可動刃１９による糸切り動作が行なわれることはない。 When the thread trimming solenoid 27 is not energized during sewing, the guide shaft 28 and the drive lever 26 stand by at the front non-engagement position indicated by the solid line in FIG. In this case, the thread trimming cam plate 25 rotates simultaneously with the sewing machine main shaft 4, but the roller member 29 does not engage with the groove cam 25a of the thread trimming cam plate 25, so that the drive lever 26 does not swing and the movable blade The thread trimming operation by 19 is not performed.
一方、縫製終了時に糸切りソレノイド２７に通電された場合は、回動板３１が糸切りソレノイド２７のプランジャで反時計回りに回動するので、案内軸２８と駆動レバー２６は、圧縮コイルバネ３０のバネ力に抗して図３において２点鎖線で示す後側の係合位置に移動する。 On the other hand, when the thread trimming solenoid 27 is energized at the end of sewing, the rotation plate 31 is rotated counterclockwise by the plunger of the thread trimming solenoid 27, so that the guide shaft 28 and the drive lever 26 are connected to the compression coil spring 30. It moves to the rear engagement position shown by a two-dot chain line in FIG. 3 against the spring force.
従って、コロ部材２９が溝カム２５ａに係合し、第１カム部Ａ〜第６カム部Ｆを順々に移動することにより、駆動レバー２６の右端部が案内軸２８を揺動支点として、第１リンク３５と共に上下に揺動し、糸切りリンク機構１５を介して可動刃１９が水平面で往復回動することにより、糸切り動作が行なわれる。 Therefore, the roller member 29 engages with the groove cam 25a and sequentially moves the first cam portion A to the sixth cam portion F, so that the right end portion of the drive lever 26 uses the guide shaft 28 as a swing fulcrum. The thread cutting operation is performed by swinging up and down together with the first link 35 and reciprocatingly rotating the movable blade 19 in the horizontal plane via the thread cutting link mechanism 15.
次に、糸切りリンク機構１５について説明する。
図１、図２に示すように、糸切りリンク機構１５は、第１〜第３リンク３５〜３７と、二股状揺動レバー３８とを有する。第１リンク３５は脚柱部２において縦向きに配設されている。第１リンク３５の上端部は、駆動レバー２６の右端部に連結され、下端部は、脚柱部２の下端部に回動可能に設けられたＬ字形状のＬ字レバー３９の第１アーム３９ｂに連結されている。
Next, the thread trimming link mechanism 15 will be described.
As shown in FIGS. 1 and 2, the thread trimming link mechanism 15 includes first to third links 35 to 37 and a bifurcated swing lever 38. The first link 35 is disposed vertically in the pedestal 2. The upper end of the first link 35 is connected to the right end of the drive lever 26, and the lower end of the first link 35 is a first arm of an L-shaped L-shaped lever 39 that is rotatably provided at the lower end of the pedestal 2. 39b.
第２リンク３６はベッド部１において前後方向向きに配設され、第２リンク３６の後端部はＬ字レバー３９の第２アーム３９ａに連結されている。第２リンク３６の前端部は、二股状揺動レバー３８に形成された下側の第２揺動アーム３８ｃに、調節リンク片（図示略）を介して連結されている。 The second link 36 is disposed in the front-rear direction in the bed portion 1, and the rear end portion of the second link 36 is connected to the second arm 39 a of the L-shaped lever 39. The front end of the second link 36 is connected to a lower second swing arm 38c formed on the bifurcated swing lever 38 via an adjustment link piece (not shown).
図１，図２に示すように、Ｌ字レバー３９の第２アーム３９ｂには、引っ張りコイルバネ４０により上向きのバネ力が作用している。第１リンク３５は、引っ張りコイルバネ４０のバネ力により常に上方に付勢力が作用し、駆動レバー２６の当接片２６ａが前述した高さ位置調節螺子（図示略）に下側から当接している。 As shown in FIGS. 1 and 2, an upward spring force is applied to the second arm 39 b of the L-shaped lever 39 by a tension coil spring 40. The first link 35 is always biased upward by the spring force of the tension coil spring 40, and the contact piece 26a of the drive lever 26 is in contact with the above-described height position adjusting screw (not shown) from below. .
第３リンク３７は、第２リンク３６よりも上側に第２リンク３６とほぼ平行にベッド部１に配設され、第３リンク３７の後端部は、二股状揺動レバー３８の上側の第１揺動アーム３８ｂにピン２３で連結されている。第３リンク３７の前端部は、可動刃１９の基端部にピン２２で連結されている。二股状揺動レバー３８は、ベッド部１内の針板８よりも後側に配設されている。二股状揺動レバー３８は、ミシン機枠に固着された縦向きの支持軸４１に回動自在に支持され、ほぼ右向き（上方から視て）に延びる上下１対の第１，第２揺動アーム３８ｂ，３８ｃを有する。 The third link 37 is disposed on the bed portion 1 so as to be substantially parallel to the second link 36 above the second link 36, and the rear end portion of the third link 37 is the second upper portion of the bifurcated swing lever 38. A pin 23 is connected to one swing arm 38b. The front end portion of the third link 37 is connected to the base end portion of the movable blade 19 with a pin 22. The bifurcated swing lever 38 is disposed on the rear side of the needle plate 8 in the bed portion 1. The bifurcated swing lever 38 is rotatably supported by a vertical support shaft 41 fixed to the sewing machine frame, and is a pair of upper and lower first and second swings extending substantially rightward (viewed from above). Arms 38b and 38c are provided.
次に、下糸繰出し機構４２について説明する。
図４、図７−２に示すように、下糸繰出し機構４２は、下糸繰出しレバー４３と、この下糸繰出しレバー４３の後端部（一端部）を針板８に連結する段付きボルト４４（これが連結部に相当する）と、リンク機構４５とを有する。下糸繰出しレバー４３は、針板８の後端から針穴８ａの前側まで延びる略直線状に形成され、この下糸繰出しレバー４３は、可動刃１９の回動領域の下側近傍において水平に往復回動可能に配設されている。
Next, the lower thread feeding mechanism 42 will be described.
As shown in FIGS. 4 and 7-2, the lower thread feeding mechanism 42 includes a lower thread feeding lever 43 and a stepped bolt for connecting the lower end (one end) of the lower thread feeding lever 43 to the needle plate 8. 44 (this corresponds to a connecting portion) and a link mechanism 45. The lower thread feeding lever 43 is formed in a substantially linear shape extending from the rear end of the needle plate 8 to the front side of the needle hole 8a, and the lower thread feeding lever 43 is horizontally in the vicinity of the lower side of the rotating region of the movable blade 19. It is arranged so as to be able to reciprocate.
下糸繰出しレバー４３の後端部は、針板８の後端部に段付きボルト４４で鉛直軸心回りに回動可能に連結されている。下糸繰出しレバー４３は、図７−１、図７−２、図１２−１、図１２−２に示す待機位置から、図８−１、図８−２、図１１−１、図１１−２に示す待機位置よりも左方の退避位置を経由して、図１０−１、図１０−２に示す最大回動位置に亙って回動し、この下糸繰出しレバー４３は、下糸１７に係合した状態で可動刃１９の待機位置の方向に回動することで、回転釜９内の下糸ボビンから下糸１７を所定量だけ繰出す。 The rear end portion of the lower thread feeding lever 43 is connected to the rear end portion of the needle plate 8 by a stepped bolt 44 so as to be rotatable around the vertical axis. The lower thread feeding lever 43 is moved from the standby position shown in FIGS. 7-1, 7-2, 12-1, 12-2 to FIGS. 8-1, 8-2, 11-1, 11-11. 2 through the retracted position on the left side of the standby position shown in FIG. 2, and rotates over the maximum turning position shown in FIGS. 10-1 and 10-2. When the movable blade 19 is rotated in the direction of the standby position while being engaged with the thread 17, the lower thread 17 is fed out from the lower thread bobbin in the rotary hook 9 by a predetermined amount.
下糸繰出しレバー４３の長さ方向途中部と、可動刃１９の基端部よりも左側の部位がリンク機構４５によって連動連結されている。リンク機構４５と下糸繰出しレバー４３はピン４６で連結され、リンク機構４５と可動刃１９はピン４７で連結されている。それ故、可動刃１９が回動すると、リンク機構４５を介して下糸繰出しレバー４３が回動するように構成されており、下糸繰出し機構４２は、糸切り駆動機構１３により糸切り動作と連動して駆動される。 A middle portion in the length direction of the lower thread feeding lever 43 and a portion on the left side of the base end portion of the movable blade 19 are interlocked and connected by a link mechanism 45. The link mechanism 45 and the lower thread feeding lever 43 are connected by a pin 46, and the link mechanism 45 and the movable blade 19 are connected by a pin 47. Therefore, when the movable blade 19 rotates, the lower thread feeding lever 43 is configured to rotate via the link mechanism 45, and the lower thread feeding mechanism 42 performs the thread trimming operation by the thread trimming drive mechanism 13. Driven in conjunction.
次に、下糸繰出し機構４２による下糸繰出し動作について、糸切り駆動機構１３による糸切り動作と対応づけて、図１３のタイミングチャートに基づいて説明する。但し、図１３において、針棒５が最上位置のときのミシン主軸４の位相角を０°とする。
縫製途中であって糸切り動作が行なわれない場合、前述したように、糸切りカム板２５はミシン主軸４と共に回転しているが、糸切りソレノイド２７に通電されないため、駆動レバー２６が図３において実線で示す前側の非作動位置に位置し且つ駆動レバー２６の当接片２６ａが高さ位置調節螺子に当接しているので、駆動レバー２６の右端部の高さ位置が位置決めされている。このとき、可動刃１９と下糸繰出しレバー４３は図７−１、図７−２に示す待機位置に位置している。
Next, the lower thread feeding operation by the lower thread feeding mechanism 42 will be described based on the timing chart of FIG. 13 in association with the yarn cutting operation by the thread trimming drive mechanism 13. However, in FIG. 13, the phase angle of the sewing machine spindle 4 when the needle bar 5 is at the uppermost position is 0 °.
When the thread trimming operation is not performed during sewing, as described above, the thread trimming cam plate 25 rotates with the sewing machine main shaft 4, but the thread trimming solenoid 27 is not energized. , The contact piece 26a of the drive lever 26 is in contact with the height position adjusting screw, so that the height position of the right end portion of the drive lever 26 is positioned. At this time, the movable blade 19 and the lower thread feeding lever 43 are positioned at the standby positions shown in FIGS. 7-1 and 7-2.
縫製処理の最終縫目を縫製したときに糸切り指令が出力されると、糸切りソレノイド２７に通電される。このとき、案内軸２８と駆動レバー２６が、圧縮コイルバネ３０のバネ力に抗して、図３において２点鎖線で示す後側の係合位置に移動して、コロ部材２９が溝カム２５ａに係合して、糸切り動作が可能になる。 If a thread trimming command is output when the last stitch of the sewing process is sewn, the thread trimming solenoid 27 is energized. At this time, the guide shaft 28 and the drive lever 26 move against the spring force of the compression coil spring 30 to the rear engagement position indicated by the two-dot chain line in FIG. 3, and the roller member 29 moves to the groove cam 25a. The thread trimming operation becomes possible by engaging.
糸切り動作の待機状態では、図７−１，図７−２に示すように、下糸１７はボビンケース５３の下糸出口５３ａから針板８の針穴８ａに向かい、上糸ループ１６ａは剣先５１ａに係合して拡大しつつある。その後、コロ部材２９が第１カム部Ａを移動するので、可動刃１９が平面視にて時計回り方向への往動動作を開始し、図８−１，図８−２に示すように、可動刃１９の糸さばき部１９ａが上糸ループ１６ａ内に突入する。このとき、下糸繰出しレバー４３はリンク機構４５によって退避位置まで（可動刃１９から遠ざかる方向へ）回動する。 In the standby state of the thread trimming operation, as shown in FIGS. 7A and 7B, the lower thread 17 is directed from the lower thread outlet 53a of the bobbin case 53 to the needle hole 8a of the needle plate 8, and the upper thread loop 16a is Enlarging by engaging with the sword 51a. Thereafter, since the roller member 29 moves in the first cam portion A, the movable blade 19 starts the forward movement in the clockwise direction in plan view, as shown in FIGS. The yarn separating portion 19a of the movable blade 19 enters the upper yarn loop 16a. At this time, the lower thread feeding lever 43 is rotated by the link mechanism 45 to the retracted position (in a direction away from the movable blade 19).
その後、コロ部材２９が第２カム部Ｂを移動するので、図８−１，図８−２に示すように、可動刃１９は、糸さばき部１９ａで上糸ループ１６ａを係合した状態で、ミシン主軸４の位相角が約２９０°〜３１０°に亙って、可動刃１９の回動動作が一時的に停止し、下糸繰出しレバー４３の回動動作も一時的に停止する。この可動刃１９の回動停止期間内に、上糸ループ１６ａがボビンケース５３に掛かり始める。 Thereafter, since the roller member 29 moves on the second cam portion B, as shown in FIGS. 8A and 8B, the movable blade 19 is in a state where the upper thread loop 16a is engaged with the thread separating portion 19a. When the phase angle of the sewing machine spindle 4 is about 290 ° to 310 °, the rotating operation of the movable blade 19 is temporarily stopped, and the rotating operation of the lower thread feeding lever 43 is also temporarily stopped. The upper thread loop 16 a starts to be hooked on the bobbin case 53 during the rotation stop period of the movable blade 19.
その後、コロ部材２９が第３カム部Ｃを移動するので、可動刃１９の糸さばき部１９ａが上糸ループ１６ａに突入する時の速度よりも高速で時計回りに可動刃１９は回動し、可動刃１９の回動に伴って、下糸繰出しレバー４３が反時計回りに回動する。上糸ループ１６ａの縫針６の目孔６ａから延びる側は、可動刃１９の係合部１９ｄと係合する。上糸ループ１６ａの加工布Ｗから延びる側は、可動刃１９の糸案内部１９ｃに沿って糸捕捉部１９ｅへ到達する。ミシン主軸４の位相角が約３４０°のとき、図９−１、図９−２に示すように、上糸ループ１６ａが回転釜９から抜け始めて、下糸繰出しレバー４３の前端部が下糸１７に係合する。この状態で、下糸繰出しレバー４３が可動刃１９の待機位置の方向に回動することにより、下糸ボビンから下糸１７が繰出される。 Thereafter, since the roller member 29 moves on the third cam portion C, the movable blade 19 rotates clockwise at a higher speed than the speed at which the yarn separating portion 19a of the movable blade 19 enters the upper thread loop 16a. As the movable blade 19 rotates, the lower thread feeding lever 43 rotates counterclockwise. The side of the upper thread loop 16 a extending from the eye hole 6 a of the sewing needle 6 engages with the engaging portion 19 d of the movable blade 19. The side of the upper thread loop 16a extending from the work cloth W reaches the thread catching section 19e along the thread guide section 19c of the movable blade 19. When the phase angle of the sewing machine main shaft 4 is about 340 °, as shown in FIGS. 9-1 and 9-2, the upper thread loop 16a starts to come out of the rotary hook 9, and the front end portion of the lower thread feeding lever 43 is lower thread. 17 is engaged. In this state, the lower thread feeding lever 43 rotates in the direction of the standby position of the movable blade 19, whereby the lower thread 17 is fed from the lower thread bobbin.
下糸繰出しレバー４３が下糸１７と係合するときには、上糸ループ１６ａの加工布Ｗから延びる側は、可動刃１９の糸捕捉部１９ｅに到達している。上糸ループ１６ａの加工布Ｗから延びる側が、糸案内部１９ｃにある状態で、下糸繰出しレバー４３が下糸１７と係合すると、下糸繰出しレバー４３が更に回動した場合、上糸ループ１６ａの加工布Ｗから延びる側は、糸案内部１９ｃに引っ掛かって切れることがある。従って、下糸繰出しレバー４３が下糸１７と係合する位置は、上糸ループ１６ａの加工布Ｗから延びる側が可動刃１９の糸捕捉部１９ｅに到達する位置となるように設定してある。 When the lower thread feeding lever 43 is engaged with the lower thread 17, the side extending from the work cloth W of the upper thread loop 16 a reaches the thread capturing portion 19 e of the movable blade 19. When the lower thread feeding lever 43 is further rotated when the lower thread feeding lever 43 is engaged with the lower thread 17 in a state where the side extending from the work cloth W of the upper thread loop 16a is in the thread guide portion 19c, the upper thread loop The side extending from the work cloth W of 16a may be cut by being caught by the yarn guide portion 19c. Therefore, the position where the lower thread feeding lever 43 engages with the lower thread 17 is set so that the side extending from the work cloth W of the upper thread loop 16a reaches the thread catching portion 19e of the movable blade 19.
ミシン主軸４の位相角が約３６０°のとき、図１０−１，図１０−２に示すように、可動刃１９が最大回動位置まで回動し、可動刃１９の回動に伴って、下糸繰出しレバー４３が最大回動位置まで回動する。このとき、下糸１７は最大限繰出されている。 When the phase angle of the sewing machine main shaft 4 is about 360 °, as shown in FIGS. 10A and 10B, the movable blade 19 rotates to the maximum rotation position. The lower thread feeding lever 43 rotates to the maximum rotation position. At this time, the lower thread 17 is drawn out to the maximum.
可動刃１９が最大回動位置まで回動した状態で、ミシン主軸４の位相角が約８°に達するまでの所定期間だけ、コロ部材２９が第４カム部Ｄを移動するので、可動刃１９の回動動作が停止する。この所定期間中に天秤により上糸１６が引き上げられる。 Since the roller member 29 moves the fourth cam portion D only for a predetermined period until the phase angle of the sewing machine spindle 4 reaches about 8 ° with the movable blade 19 rotated to the maximum rotation position, the movable blade 19 is moved. Rotation operation stops. During this predetermined period, the upper thread 16 is pulled up by the balance.
その後、コロ部材２９が第５，第６カム部Ｅ，Ｆを連続して移動するので、ミシンＭが停止するまでの間に、図１２−１、図１２−２に示すように、可動刃１９が待機位置まで往動よりも速い高速で復帰回動し、可動刃１９の回動に伴って、下糸繰出しレバー４３が待機位置まで復帰回動する。図１１−１、図１１−２に示すように、可動刃１９が待機位置へ復帰回動する途中で、糸捕捉部１９ｅが下糸１７を捕捉する。上糸ループ１６ａの加工布Ｗ側と下糸１７とが、可動刃１９と固定刃１８との協働により同時に切断される。このとき、下糸繰出しレバー４３は退避位置に位置する。 Thereafter, since the roller member 29 continuously moves through the fifth and sixth cam portions E and F, as shown in FIGS. 12A and 12B, the movable blade until the sewing machine M stops. 19 rotates back to the standby position at a higher speed than the forward movement, and the lower thread feeding lever 43 returns to the standby position as the movable blade 19 rotates. As shown in FIGS. 11A and 11B, the thread catching portion 19 e catches the lower thread 17 while the movable blade 19 is rotated back to the standby position. The work thread W side and the lower thread 17 of the upper thread loop 16 a are simultaneously cut by the cooperation of the movable blade 19 and the fixed blade 18. At this time, the lower thread feeding lever 43 is located at the retracted position.
次に、以上説明した糸切り装置１１の作用、効果について説明する。
この糸切り装置１１では、糸切り指令が出力されると、可動刃１９が待機位置から時計回りに回動開始し、可動刃１９の回動に伴って、下糸繰出しレバー４３が待機位置から退避位置を経由し最大回動位置に亙って回動開始する。
Next, the operation and effect of the thread trimming device 11 described above will be described.
In this thread trimming device 11, when a thread trimming command is output, the movable blade 19 starts to rotate clockwise from the standby position, and as the movable blade 19 rotates, the lower thread feeding lever 43 moves from the standby position. The rotation starts to reach the maximum rotation position via the retreat position.
上糸ループ１６ａに可動刃１９の糸さばき部１９ａが係合した後、上糸ループ１６ａの加工布Ｗから延びる側が可動刃１９の糸捕捉部１９ｅに到達したときに、下糸繰出しレバー４３の前端部が下糸１７に係合し、この状態で、下糸繰出しレバー４３が可動刃１９の待機位置の方向に回動することにより下糸ボビンから下糸１７が繰出される。可動刃１９が最大回動位置に達したとき、下糸繰出しレバー４３が最大回動位置まで回動し、このとき、下糸１７が最大限繰出されている。 After the yarn separating portion 19a of the movable blade 19 is engaged with the upper yarn loop 16a, when the side extending from the work cloth W of the upper yarn loop 16a reaches the yarn catching portion 19e of the movable blade 19, the lower yarn feeding lever 43 The front end engages with the lower thread 17, and in this state, the lower thread feeding lever 43 is rotated in the direction of the standby position of the movable blade 19, whereby the lower thread 17 is fed out from the lower thread bobbin. When the movable blade 19 reaches the maximum rotation position, the lower thread feeding lever 43 rotates to the maximum rotation position, and at this time, the lower thread 17 is extended to the maximum.
その後、可動刃１９が待機位置まで往動よりも高速で復帰回動するが、可動刃１９が待機位置へ復帰回動する途中で、加工布Ｗ側の上糸１６と下糸１７が、可動刃１９と固定刃１８との協働により同時に切断される。このとき、下糸１７が切断される部分に適度な弛みを持たせたので、糸切り時に下糸１７を切断する際に下糸１７の張力が下糸ボビンに伝達されず下糸ボビンが空転しない。 Thereafter, the movable blade 19 returns to the standby position at a higher speed than the forward movement, but the upper thread 16 and the lower thread 17 on the work cloth W side move while the movable blade 19 returns to the standby position. The blade 19 and the fixed blade 18 are simultaneously cut by the cooperation. At this time, since the portion where the lower thread 17 is cut has an appropriate slack, the tension of the lower thread 17 is not transmitted to the lower thread bobbin when the lower thread 17 is cut at the time of thread trimming, and the lower thread bobbin idles. do not do.
このように、可動刃１９がその待機位置から回動開始後、縫針６の目孔６ａから加工布Ｗを通過して延びた上糸１６に回転釜９の外釜５１と剣先５１ａにより形成された上糸ループ１６ａに、可動刃１９の糸さばき部１９ａが係合開始した後糸切り前に、回転釜９から延びる下糸１７を所定量だけ繰出す下糸繰出し機構４２を設けたので、糸切り前に下糸１７に対して適度な弛みを持たせることができる。これにより、糸切り時に下糸１７を切断する際、下糸１７の張力が下糸ボビンに伝達されないため、下糸ボビンの空転を防止することができ、縫製再開後の縫い調子が不安定にならない。 Thus, after the movable blade 19 starts to rotate from its standby position, the upper thread 16 extending through the work cloth W from the eye hole 6a of the sewing needle 6 is formed by the outer hook 51 and the blade tip 51a of the rotary hook 9. Since the upper thread loop 16a is provided with a lower thread feeding mechanism 42 for feeding the lower thread 17 extending from the rotary hook 9 by a predetermined amount before thread trimming after the thread separating portion 19a of the movable blade 19 starts to be engaged. Appropriate slack can be given to the lower thread 17 before thread trimming. As a result, when the lower thread 17 is cut at the time of thread trimming, the tension of the lower thread 17 is not transmitted to the lower thread bobbin, so that the lower thread bobbin can be prevented from idling, and the sewing condition after resuming sewing becomes unstable. Don't be.
下糸繰出し機構４２は、可動刃１９の回動領域の下側近傍において水平に往復回動可能な下糸繰出しレバー４３を備え、下糸繰出しレバー４３が下糸１７に係合した状態で可動刃１９の待機位置の方向に回動することで、回転釜９内の下糸ボビンから下糸１７を繰出すので、下糸１７を可動刃１９の待機位置の方向に繰出すことができる。それ故、糸切り時に可動刃１９の回動により下糸１７を確実に捕捉して切断することができる。下糸繰出し機構４２は、糸切り駆動機構１３により糸切り動作と連動して駆動されるので、可動刃１９の回動に連動して下糸繰出しレバー４３を回動することができ、糸切り前に下糸１７を確実に繰出すことができる。 The lower thread feeding mechanism 42 includes a lower thread feeding lever 43 that can be reciprocated horizontally in the vicinity of the lower side of the rotation area of the movable blade 19, and is movable in a state where the lower thread feeding lever 43 is engaged with the lower thread 17. By rotating in the direction of the standby position of the blade 19, the lower thread 17 is fed out from the lower thread bobbin in the rotary hook 9, so that the lower thread 17 can be fed out in the direction of the standby position of the movable blade 19. Therefore, the lower thread 17 can be reliably captured and cut by turning the movable blade 19 during thread trimming. Since the lower thread feeding mechanism 42 is driven by the thread trimming drive mechanism 13 in conjunction with the thread trimming operation, the lower thread feeding lever 43 can be rotated in conjunction with the rotation of the movable blade 19, and the thread trimming mechanism 42 can be rotated. The lower thread 17 can be reliably fed out before.
下糸繰出し機構４２は、下糸繰出しレバー４３と、この下糸繰出しレバー４３の一端部を鉛直軸心回りに回動可能に連結する段付きボルト４４と、この下糸繰出しレバー４３の長さ方向途中部を可動刃１９に連動連結するリンク機構４５とを有するので、下糸繰出し機構４２を簡単な構成で実現することができる。下糸繰出し機構４２は、可動刃１９がその最大回動位置へ回動する前（上糸ループ１６ａの加工布Ｗから延びる側が可動刃１９の糸捕捉部１９ｅに到達したとき）に、下糸１７に係合開始し且つ可動刃１９が最大回動位置に達したときに下糸１７を最大限繰出すので、下糸繰出しレバー４３による上糸１６の挟み込みを防止しつつ、下糸１７のみを確実に繰出すことができる。 The lower thread feeding mechanism 42 includes a lower thread feeding lever 43, a stepped bolt 44 that rotatably connects one end of the lower thread feeding lever 43 about a vertical axis, and the length of the lower thread feeding lever 43. Since the link mechanism 45 that interlocks and links the middle part in the direction to the movable blade 19 is provided, the lower thread feeding mechanism 42 can be realized with a simple configuration. The lower thread feeding mechanism 42 is configured to lower the lower thread before the movable blade 19 rotates to its maximum rotation position (when the side extending from the work cloth W of the upper thread loop 16a reaches the thread catching portion 19e of the movable blade 19). Since the lower thread 17 is fed out to the maximum when the movable blade 19 reaches the maximum rotation position when engagement with the lower thread 17 is reached, only the lower thread 17 is prevented from being caught by the lower thread feeding lever 43. Can be reliably delivered.
次に、前記実施例を部分的に変更した変更例について説明する。
１］下糸繰出しレバー４３と可動刃１９をリンク機構４５で連動連結する代わりに、下糸繰出しレバー４３にアクチュエータを直接接続し、糸切り駆動機構１３による糸切り動作と連動して下糸繰出しレバー４３による下糸繰出し動作が行われるように、アクチュエータを速度制御してもよい。また、下糸繰出しレバー４３に接続したアクチュエータとは別のアクチュエータを可動刃１９に直接接続し、可動刃１９による糸切り動作と連動して下糸繰出しレバー４３による下糸繰出し動作が行われるように、２つのアクチュエータを夫々速度制御してもよい。
Next, a modified example in which the above embodiment is partially modified will be described.
1] Instead of interlocking the lower thread feeding lever 43 and the movable blade 19 with the link mechanism 45, an actuator is directly connected to the lower thread feeding lever 43, and the lower thread feeding is interlocked with the thread trimming operation by the thread trimming drive mechanism 13. The speed of the actuator may be controlled so that the lower thread feeding operation by the lever 43 is performed. Further, an actuator different from the actuator connected to the lower thread feeding lever 43 is directly connected to the movable blade 19 so that the lower thread feeding operation by the lower thread feeding lever 43 is performed in conjunction with the thread trimming operation by the movable blade 19. In addition, the speeds of the two actuators may be controlled respectively.
Ｍ ミシン
４ 主軸
６ 縫針
６ａ 目孔
８ 針板
９ 回転釜
１１ 糸切り装置
１２ 糸切り機構
１３ 糸切り駆動機構
１６ 上糸
１６ａ 上糸ループ
１７ 下糸
１８ 固定刃
１９ 可動刃
１９ｅ 糸捕捉部
４２ 下糸繰出し機構
４３ 下糸繰出しレバー
４４ 段付きボルト
４５ リンク機構
５１ 外釜
５１ａ 剣先
M sewing machine 4 main shaft 6 sewing needle 6a eye hole 8 throat plate 9 rotary hook 11 thread trimming device 12 thread trimming mechanism 13 thread trimming drive mechanism 16 upper thread 16a upper thread loop 17 lower thread 18 fixed blade 19 movable blade 19e thread catching section 42 lower Thread feeding mechanism 43 Lower thread feeding lever 44 Stepped bolt 45 Link mechanism 51 Outer hook 51a Blade tip
Claims (6)
前記可動刃がその待機位置から回動開始後、前記縫針の目孔から加工布を通過して延びた上糸に前記回転釜の外釜と剣先により形成された上糸ループに、前記可動刃の尖端部が係合開始した後糸切り前に、回転釜から延びる下糸を所定量だけ繰出す下糸繰出し機構を設けたことを特徴とするミシンの糸切り装置。 A sewing machine having a rotary hook having an outer hook that rotates in synchronization with the vertical movement of the sewing needle by the main shaft below the needle plate can be reciprocated horizontally with a fixed blade provided near the lower surface of the needle plate. In a thread trimming device provided with a thread trimming mechanism having a movable blade and a thread trimming drive mechanism for rotationally driving the movable blade,
After the movable blade starts rotating from its standby position, an upper thread loop formed by an outer hook of the rotary hook and a sword tip is formed on the upper thread extending through the work cloth from the eye hole of the sewing needle. A thread trimming device for a sewing machine is provided with a lower thread feeding mechanism that feeds a predetermined amount of lower thread extending from the rotary hook before thread trimming after engagement of the tip end of the sewing machine.
前記下糸繰出しレバーが下糸に係合した状態で前記可動刃の待機位置の方向に回動することで、前記回転釜内のボビンから下糸を繰出すことを特徴とする請求項１に記載のミシンの糸切り装置。 The lower thread feeding mechanism includes a lower thread feeding lever that can be horizontally reciprocated in the vicinity of the lower side of the movable blade.
The bobbin thread is fed out from a bobbin in the rotary hook by rotating the lower thread feeding lever in the direction of the standby position of the movable blade while being engaged with the lower thread. The thread trimming device of the description sewing machine.
前記下糸繰出しレバーは、前記上糸ループの加工布から延びる側が前記可動刃の糸捕捉部に到達したときに下糸と係合することを特徴とする請求項２〜５の何れかに記載のミシンの糸切り装置。 The movable blade has a yarn catching portion for catching a side extending from the work cloth of the upper yarn loop,
The said lower thread feeding lever engages with a lower thread when the side extended from the work cloth of the said upper thread loop reaches | attains the thread | yarn capture part of the said movable blade, The lower thread is characterized by the above-mentioned. Sewing machine thread trimming device.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008038739A JP2009195382A (en) | 2008-02-20 | 2008-02-20 | Thread cutter of sewing machine |
| CN2009100067316A CN101514518B (en) | 2008-02-20 | 2009-02-19 | Severing thread device for sewing machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008038739A JP2009195382A (en) | 2008-02-20 | 2008-02-20 | Thread cutter of sewing machine |
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| Publication Number | Publication Date |
|---|---|
| JP2009195382A true JP2009195382A (en) | 2009-09-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2008038739A Pending JP2009195382A (en) | 2008-02-20 | 2008-02-20 | Thread cutter of sewing machine |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2009195382A (en) |
| CN (1) | CN101514518B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2017080315A (en) * | 2015-10-30 | 2017-05-18 | ブラザー工業株式会社 | Thread cutting mechanism and sewing machine |
| CN106676774B (en) * | 2017-01-13 | 2023-07-07 | 湖南兴德缝制股份有限公司 | Shuttle core lock device for preventing shuttle core of sewing machine from rotating |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2623729Y (en) * | 2003-02-09 | 2004-07-07 | 张武雄 | Clutch device for rotating shuttle drive shaft of sewing machine |
| CN101363173B (en) * | 2007-08-08 | 2012-02-01 | 高林股份有限公司 | Lower line shearing device of sewing machine |
-
2008
- 2008-02-20 JP JP2008038739A patent/JP2009195382A/en active Pending
-
2009
- 2009-02-19 CN CN2009100067316A patent/CN101514518B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101514518B (en) | 2012-06-06 |
| CN101514518A (en) | 2009-08-26 |
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