JPH08327328A - Apparatus for detecting let-off amount of thread of sewing machine - Google Patents

Abstract

PURPOSE: To provide a detecting device for detecting the let-off amount of threads of a sewing machine which is inexpensive, highly accurate, reduces erroneous detection can follow the moving speed of threads. CONSTITUTION: The detecting device 20 for detecting the let-off amount of threads is arranged between a needle 18a reciprocating up and down when a sewing machine is driven and a thread feed means 11 for feeding a thread 19. The detecting device has a winding part to an outer periphery of which is wound the thread, a turning member 21 which is turned or stopped simultaneously when the thread is let off or stopped, and a detecting means 22 for photographing the side face of the turning member 21 by a CCD element 22b to detect the turning amount of the turning member 21.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、ミシンの糸繰り出し量
検出装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yarn threading amount detecting device for a sewing machine.

【０００２】[0002]

【従来の技術】ミシンにおいては、図４の（ａ）や
（ｃ）に示されるように、上糸１００もしくは下糸１０
１の調和が一方に偏ると、上糸１００と下糸１０１とが
引っ掛かり合う位置が布１０２の上方もしくは下方側に
ずれ、良好な縫い目が得られない。2. Description of the Related Art In a sewing machine, as shown in FIGS. 4 (a) and 4 (c), an upper thread 100 or a lower thread 10 is used.
If the harmony of 1 is biased to one side, the position where the upper thread 100 and the lower thread 101 are caught deviates to the upper side or the lower side of the cloth 102, and good seams cannot be obtained.

【０００３】又、図４の（ｂ）に示されるように、ミシ
ンの上糸１００と下糸１０１とを、布１０２の中央付近
の調和がとれた状態で縫い合わせ、良好な縫い目を得る
ためには、糸の繰り出し量を逐次測定し、それに応じて
糸の張力を変化させることが望ましい。Further, as shown in FIG. 4B, the upper thread 100 and the lower thread 101 of the sewing machine are sewn together in a harmonious state near the center of the cloth 102 to obtain a good seam. For, it is desirable to successively measure the unwinding amount of the yarn and change the tension of the yarn accordingly.

【０００４】このようなときに用いられる糸の繰り出し
量を検出する手段としては、例えば１９８４年３月１０
日に株式会社朝倉書店より発行された「レーザ応用技術
ハンドブック」の３５４頁に開示されているような、レ
ーザドプラー計を利用することが考えられるが、これ
は、２つのレーザを干渉させ、被検出部に入射したレー
ザの散乱光のドプラー周波数変化を測定することによっ
て、被検出物の移動量を検出するものであるが、各光学
部品の加工やその配置、組付けには非常に高精度が要求
される。このため、製作上のコストや部品の製造コスト
がかかり、非常に高価なものとなってしまう。又、一般
的に知られているロータリーエンコーダを利用して安価
な構成にすることも考えられる。しかしながら、このよ
うなロータリーエンコーダでは、糸の繰り出し量を測定
する際に、糸に過大な張力がかかり弊害となる。過大な
張力がかかる場合としては、回転軸の起動トルク、慣性
による過大検知などがある。糸の繰り出し量を細かく測
定するためにエンコーダの分解能を向上させると、糸の
移動速度（最大約１．５ｍ／ｓ）に追従することができ
なくなるという問題がある。As a means for detecting the amount of unrolled yarn used in such a case, for example, March 10, 1984
It is conceivable to use a laser Doppler meter as disclosed on page 354 of the "Laser Application Technology Handbook" issued by Asakura Shoten Co., Ltd., but this causes two lasers to interfere with each other. The amount of movement of the object to be detected is detected by measuring the change in the Doppler frequency of the scattered light of the laser that has entered the detector, but it is extremely accurate in the processing, placement and assembly of each optical component. Is required. For this reason, the manufacturing cost and the manufacturing cost of parts are increased, which is very expensive. It is also possible to use a generally known rotary encoder to provide an inexpensive structure. However, in such a rotary encoder, an excessive tension is applied to the yarn when measuring the amount of the delivered yarn, which is a problem. Examples of cases where excessive tension is applied include starting torque of the rotating shaft and excessive detection due to inertia. If the resolution of the encoder is improved in order to measure the yarn feeding amount finely, there is a problem that it becomes impossible to follow the yarn moving speed (maximum of about 1.5 m / s).

【０００５】[0005]

【発明が解決しようとする課題】本発明は、安価で、高
精度、誤検知の低減、更に糸の移動速度にも追従可能な
ミシンの糸繰り出し量検出装置の提供を技術的課題とす
る。SUMMARY OF THE INVENTION An object of the present invention is to provide a thread feeding amount detecting device for a sewing machine which is inexpensive, has high accuracy, reduces erroneous detection, and can follow the moving speed of the thread.

【０００６】[0006]

【課題を解決するための手段】上記した技術的課題を解
決するため請求項１の発明において講じた技術的手段
は、ミシン駆動時に上下に往復運動される針と糸を供給
するための糸供給手段との間に配設される糸繰り出し量
検出装置において、外周に糸が巻きつけられる巻回部を
有し、糸の繰り出し動作又は停止動作と同時に回動又は
停止する回動部材と、回動部材の側面をＣＣＤ素子にて
取り込み、回動部材の回動量を検出する検出手段とを備
えたことである。In order to solve the above-mentioned technical problems, the technical means taken in the invention of claim 1 is a thread supply for supplying a needle and a thread which are reciprocally moved up and down when a sewing machine is driven. In the yarn feeding amount detecting device arranged between the device and the means, there is provided a winding member around which the yarn is wound, the rotating member rotating or stopping simultaneously with the yarn feeding operation or the stopping operation, and a rotating member. This is to include a detection means for taking in the side surface of the moving member with a CCD element and detecting the amount of rotation of the rotating member.

【０００７】回動部材が糸の動きにより追従できるよう
にするため、請求項２の発明において講じた技術的手段
は、回動部材の糸供給手段側及び針側にそれぞれ配設さ
れ、糸に所定の張力を付与する張力付与手段を備えたこ
とである。In order to enable the rotating member to follow the movement of the yarn, the technical means taken in the invention of claim 2 are provided on the yarn supplying means side and the needle side of the rotating member, respectively, and That is, a tension applying means for applying a predetermined tension is provided.

【０００８】[0008]

【作用】請求項１の発明においては、糸供給手段から供
給される糸が回動部材の巻回部に巻回されているため、
回動部材と糸とは両者間の摩擦力によって同時に回動し
たり停止したりする。検出手段は、回動部材の側面をＣ
ＣＤ素子にて撮影し、撮影した像の擦れから回動部材の
回動量を測定し、回動部材の回動量から糸の繰り出し量
を演算する。In the invention of claim 1, since the yarn supplied from the yarn supplying means is wound around the winding portion of the rotating member,
The rotating member and the thread simultaneously rotate and stop due to the frictional force between them. The detecting means has a side surface C of the rotating member.
An image is taken with a CD element, the amount of turning of the turning member is measured from the rubbing of the taken image, and the amount of thread delivery is calculated from the amount of turning of the turning member.

【０００９】請求項２の発明においては、張力付与手段
が回動部材の糸供給手段側及び針側にそれぞれ配設され
ているため、糸を回動部材に押さえつけることができ、
糸と回動部材との間の摩擦力を向上させることができ
る。According to the second aspect of the present invention, since the tension applying means is arranged on the yarn supplying means side and the needle side of the rotating member, the yarn can be pressed against the rotating member.
The frictional force between the yarn and the rotating member can be improved.

【００１０】[0010]

【実施例】本発明に係る一実施例を図面に基づいて説明
する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

【００１１】図１は本実施例の糸繰り出し量検出装置を
採用したミシンの外観斜視図、図２は本実施例の糸繰り
出し量検出装置の外観斜視図である。FIG. 1 is an external perspective view of a sewing machine which employs the yarn feeding amount detecting device of this embodiment, and FIG. 2 is an external perspective view of the yarn feeding amount detecting device of this embodiment.

【００１２】図において、ミシン１０のヘッド部１０ａ
には、糸供給装置である糸駒１１、糸繰り出し量検出装
置２０、糸調子器１２、糸掛け１３、糸案内１４、１
５、１７、天ビン１６、針１８ａを上下に駆動するため
の針棒１８が取り付けられている。糸１９は、糸駒１１
から糸繰り出し量検出装置２０を経て、糸調子器１２に
巻回され、更に糸掛け１３、糸案内１４、天ビン１６、
糸案内１５、１７を通って針１８ａに至る。In the drawing, the head portion 10a of the sewing machine 10 is shown.
Includes a thread spool 11, which is a thread supply device, a thread delivery amount detection device 20, a thread tensioner 12, a thread hook 13, a thread guide 14, and 1.
5, 17, the top bottle 16, and a needle bar 18 for driving the needle 18a up and down are attached. The thread 19 is the thread spool 11.
From the yarn winding amount detecting device 20 to the yarn tension device 12, the yarn hooking device 13, the yarn guide 14, the top bin 16,
It reaches the needle 18a through the thread guides 15 and 17.

【００１３】糸繰り出し量検出装置２０は、回動部材２
１、検出手段２２、予備調子（張力付与手段）２３、２
４から構成されている。回動部材２１は、軸受け部材２
１ａに回動自在に支持されていて、その外周面には図３
に示されるような断面がＶ字状の溝（巻回部）２１ｂが
全周に亘って設けられている。回動部材２１は、軽量
で、耐摩耗性及び自己潤滑性に優れているものが採用さ
れ、例えばアクリル、ＦＲＰ、テフロン等が利用でき
る。The yarn feeding amount detecting device 20 includes a rotating member 2
1, detection means 22, preliminary tone (tensioning means) 23, 2
4. The rotating member 21 is the bearing member 2
1a is rotatably supported, and the outer peripheral surface of FIG.
A groove (wound portion) 21b having a V-shaped cross section as shown in is provided over the entire circumference. As the rotating member 21, a member that is lightweight and has excellent wear resistance and self-lubricating property is adopted, and for example, acrylic, FRP, Teflon or the like can be used.

【００１４】検出手段２２は、検出精度を向上させるた
めにミシンヘッド部１０ａの上面に対してα°（約６
°）傾けた状態で、ミシンヘッド部１０ａの上面に取り
付けられている。検出手段２２は、内部にレーザ発光手
段とＣＣＤ素子を備えていて、発光部２２ａより回動部
材２１の側面に配置された反射リング２１ａに向けてレ
ーザを照射し、反射リング２１ａのレーザが当たってい
る部分をカメラ２２ｂにて撮像するようになっている。
カメラ２２ｂは、一定時間毎に撮像を行うようにして、
画像のずれ量から回動部材２１の回動量を検出する。回
動部材２１がアクリルのような透明な材質から成ってい
るときには、レーザが透過してしまうために、レーザの
光が透過しないような材質（例えばアクリルの片面に塗
料を塗布したものやＦＲＰ）からなる反射リング２１ａ
を、レーザが照射される位置に固定しておくとよい。The detecting means 22 has an angle of α ° (about 6) with respect to the upper surface of the sewing machine head portion 10a in order to improve the detection accuracy.
) Attached to the upper surface of the sewing machine head portion 10a in a tilted state. The detecting means 22 has a laser light emitting means and a CCD element inside, and irradiates the laser from the light emitting portion 22a to the reflecting ring 21a arranged on the side surface of the rotating member 21 so that the laser of the reflecting ring 21a is hit. The camera 22b takes an image of the portion where
The camera 22b captures images at regular intervals,
The rotation amount of the rotation member 21 is detected from the image shift amount. When the rotating member 21 is made of a transparent material such as acrylic, a laser is transmitted therethrough, so that a material that does not transmit laser light (for example, acrylic coated on one side or FRP). Reflective ring 21a
Should be fixed at the position where the laser is irradiated.

【００１５】予備調子（張力付与手段）２３、２４は、
保持器２５によりミシンヘッド部１０ａの側面に保持さ
れている。糸駒１１からの糸は、保持器２５の穴２５ａ
内を通って予備調子２３に巻かれ、回動部材２１の溝２
１ｂを経て予備調子２４に巻かれている。本実施例にお
いては、回動部材２１及び予備調子２３間の糸１９ａと
回動部材２１及び予備調子２４間の糸１９ｂとが交差す
るように、予備調子２３、２４を配設しているため、糸
１９が回動部材２１に接触している面積が大きくでき、
両者の間の摩擦力が大きくなる。又、張力付与手段２
３、２４が回動部材２１の糸駒１１側及び針１９側にそ
れぞれ配設されているため、糸１９を回動部材２１に押
さえつけることができ、糸１９と回動部材２１との間の
摩擦力を向上させることができる。これによって、回動
部材２１の動きが糸の動きに追従しやすくなる。The pre-conditioners (tensioning means) 23 and 24 are
The holder 25 holds the side surface of the sewing machine head 10a. The thread from the thread spool 11 is inserted into the hole 25a of the cage 25.
It is wound around the preliminary tone 23 through the inside of the groove 2 of the rotating member 21.
It is wound on the preliminary tone 24 through 1b. In the present embodiment, the pre-conditioners 23 and 24 are arranged so that the yarn 19a between the rotating member 21 and the pre-conditioner 23 intersects with the yarn 19b between the rotating member 21 and the pre-conditioner 24. , The area in which the thread 19 is in contact with the rotating member 21 can be increased,
The frictional force between the two becomes large. Also, the tension applying means 2
Since the yarns 3 and 24 are disposed on the thread member 11 side and the needle 19 side of the rotating member 21, respectively, the yarn 19 can be pressed down by the rotating member 21, and between the yarn 19 and the rotating member 21. The frictional force can be improved. This facilitates the movement of the rotating member 21 to follow the movement of the yarn.

【００１６】本実施例においては、糸１９が糸駒１１よ
り繰り出されると、糸１９が移動し、糸と回動部材２１
との間の摩擦によって回動部材２１が回転運動し、繰り
出された量に相当する分だけ回動部材２１が回動する。
この回動量は、検出手段２０によって検出され、糸１９
の繰り出し量が演算される。In this embodiment, when the thread 19 is unwound from the thread spool 11, the thread 19 moves, and the thread and the rotating member 21.
The rotating member 21 rotates due to the friction between the rotating member 21 and the rotating member 21, and the rotating member 21 rotates by an amount corresponding to the amount of feeding.
This rotation amount is detected by the detection means 20 and the yarn 19
Is calculated.

【００１７】本実施例においては、糸繰り出し量検出装
置２０において上糸の繰り出し量を逐次検出して、１針
当たりの理論的な繰り出し量から求められる目標値との
差を求める。この差をフィードバックして、糸の繰り出
し量が増えたら糸調子器１２が糸に与える張力を増加さ
せ、逆に繰り出し量が減ったら糸調子器１２により糸の
張力を減少させるようにする。これによって、時間的に
変動する縫いムラを防止することができ、図４の（ｂ）
に示されるような良好な縫い目を得ることができる。
又、本実施例においては、糸繰り出し量検出装置２０を
ミシンヘッド１０ａに取り付け、上糸の繰り出し量のみ
を検出しているが、ミシンテーブル１０ｂにも取り付
け、上下の糸の繰り出し量を検出してフィードバックす
れば、更に、良好な縫い目を得ることができる。In the present embodiment, the yarn feeding amount detecting device 20 sequentially detects the feeding amount of the upper yarn, and obtains the difference from the target value obtained from the theoretical feeding amount per needle. By feeding back this difference, the tension applied to the yarn by the thread tension device 12 is increased when the amount of thread delivery is increased, and conversely, when the amount of delivery is decreased, the tension of the thread is decreased by the thread tension device 12. As a result, it is possible to prevent time-varying unevenness in sewing, and as shown in FIG.
It is possible to obtain a good seam as shown in FIG.
Further, in the present embodiment, the yarn feeding amount detecting device 20 is attached to the sewing machine head 10a to detect only the feeding amount of the upper thread, but it is also attached to the sewing machine table 10b to detect the feeding amount of the upper and lower yarns. If such feedback is provided, a better seam can be obtained.

【００１８】又、上記した糸繰り出し量と目標値との差
が、あるしきい値を越えた場合に、糸の締まり過ぎ、緩
み過ぎなどの異常検知としても利用できる。Further, when the difference between the above-mentioned yarn feeding amount and the target value exceeds a certain threshold value, it can also be used for detecting abnormality such as excessive tightening or loosening of the yarn.

【００１９】[0019]

【発明の効果】請求項１の発明においては、回動部材の
半径やＣＣＤ素子にて撮影する回動部材の部分を自由に
変更することができるため、精度及び追従可能速度を向
上させたいときには、回動部材の半径を大きくしたり、
ＣＣＤ素子にて撮影する部分を回動部材の外周側に移動
させたりすれば、回動部材の回動量に対する糸の繰り出
し量が大きくなり、結果、糸の繰り出し量を細かい時間
単位で測定することができると共に、糸の移動速度にも
追従させることができる。又、構造が簡素なために、低
コストでもある。According to the first aspect of the invention, the radius of the rotating member and the portion of the rotating member for photographing with the CCD element can be freely changed. Therefore, when it is desired to improve accuracy and followable speed. , Increase the radius of the rotating member,
If the portion to be photographed by the CCD element is moved to the outer peripheral side of the rotating member, the amount of yarn unwinding with respect to the amount of rotation of the rotating member becomes large, and as a result, the amount of yarn unwinding can be measured in fine time units. In addition to being able to perform, it is possible to follow the moving speed of the yarn. In addition, since the structure is simple, the cost is low.

【００２０】請求項２の発明においては、張力付与手段
が回動部材の糸供給手段側及び針側にそれぞれ配設され
ているため、糸を回動部材に押さえつけられて糸と回動
部材との間の摩擦力を向上させることができ、結果、糸
と回動部材との間のすべりを少なくすることができて検
出精度を向上させることができる。According to the second aspect of the invention, since the tension applying means is arranged on the thread supplying means side and the needle side of the rotating member, respectively, the thread is pressed by the rotating member and the yarn and the rotating member are connected. It is possible to improve the frictional force between the yarns, and as a result, it is possible to reduce slippage between the yarn and the rotating member and improve the detection accuracy.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明に係る糸繰り出し量検出装置を採用した
ミシンの外観斜視図を示す。FIG. 1 is an external perspective view of a sewing machine that employs a yarn feeding amount detection device according to the present invention.

【図２】本発明に係る糸繰り出し量検出装置の外観斜視
図を示す。FIG. 2 is an external perspective view of a yarn feeding amount detection device according to the present invention.

【図３】回動部材の一部分の断面図を示す。FIG. 3 shows a cross-sectional view of a portion of a rotating member.

【図４】縫い目の断面図を示していて、（ａ）は上糸の
張力が大き過ぎる場合、（ｂ）は良好な縫い目、（ｃ）
は下糸の張力が大きすぎる場合を示している。FIG. 4 is a cross-sectional view of a seam, where (a) is a case where the needle thread tension is too high, (b) is a good seam, and (c) is
Shows the case where the tension of the lower thread is too high.

【符号の説明】[Explanation of symbols]

１１・・・糸駒（糸供給手段） １８ａ・・・針 １９・・・糸 ２０・・・糸繰り出し量検出装置 ２１・・・回動部材 ２１ａ・・・反射リング ２２・・・検出手段 ２３、２４・・・予備調子 ２５・・・保持器 11 ... Thread piece (thread supply means) 18a ... Needle 19 ... Thread 20 ... Thread feeding amount detection device 21 ... Rotating member 21a ... Reflection ring 22 ... Detection means 23 , 24 ・ ・ ・ Preliminary condition 25 ・ ・ ・ Cage

フロントページの続き (72)発明者 鎌 田 佳 伸 千葉県流山市平和台５−35−16 (72)発明者 加 藤 豊 文 東京都日野市百草315−１ コスモ聖蹟桜 ヶ丘503Front Page Continuation (72) Inventor Yoshinobu Kamata 5-35-16 Heiwadai, Nagareyama City, Chiba Prefecture (72) Toyofumi Kato 315-1 Hyakusa, Hino City, Tokyo Cosmo Seisekisakuragaoka 503

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 ミシン駆動時に上下に往復運動される針
と糸を供給するための糸供給手段との間に配設される糸
繰り出し量検出装置において、 外周に前記糸が巻きつけられる巻回部を有し、前記糸の
繰り出し動作又は停止動作と同時に回動又は停止する回
動部材と、 該回動部材の側面をＣＣＤ素子にて撮影し、前記回動部
材の回動量を検出する検出手段とを備えたことを特徴と
するミシンの糸繰り出し量検出装置。1. A yarn winding amount detecting device arranged between a needle that is vertically reciprocated when a sewing machine is driven and a yarn supplying means for supplying a yarn, in which the yarn is wound around the outer circumference. And a rotation member that rotates or stops at the same time as the yarn feeding operation or the stopping operation, and a detection that detects the rotation amount of the rotation member by photographing the side surface of the rotation member with a CCD element. And a means for detecting the amount of thread unwinding of the sewing machine. 【請求項２】 前記回動部材の前記糸供給手段側及び前
記針側にそれぞれ配設され、前記糸に所定の張力を付与
する張力付与手段を備えたことを特徴とする請求項１記
載のミシンの糸繰り出し量検出装置。2. The tension applying means, which is provided on the thread supplying means side and the needle side of the rotating member, respectively, and applies a predetermined tension to the thread. Sewing machine thread feeding amount detection device.