EP0879909B1 - Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire - Google Patents

Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire Download PDF

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Publication number
EP0879909B1
EP0879909B1 EP19980108242 EP98108242A EP0879909B1 EP 0879909 B1 EP0879909 B1 EP 0879909B1 EP 19980108242 EP19980108242 EP 19980108242 EP 98108242 A EP98108242 A EP 98108242A EP 0879909 B1 EP0879909 B1 EP 0879909B1
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EP
European Patent Office
Prior art keywords
heald
linear motors
heald frame
frames
shedding motion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19980108242
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German (de)
English (en)
Other versions
EP0879909A1 (fr
Inventor
Tatsuya Uematsu
Masaki Takasan
Yochi Saito
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Industries Corp
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Toyota Industries Corp
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Filing date
Publication date
Application filed by Toyota Industries Corp filed Critical Toyota Industries Corp
Priority to EP02003317A priority Critical patent/EP1215318A2/fr
Publication of EP0879909A1 publication Critical patent/EP0879909A1/fr
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Publication of EP0879909B1 publication Critical patent/EP0879909B1/fr
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    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
    • D03C13/00—Shedding mechanisms not otherwise provided for
    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
    • D03C13/00—Shedding mechanisms not otherwise provided for
    • D03C13/02—Shedding mechanisms not otherwise provided for with independent drive motors
    • D03C13/025—Shedding mechanisms not otherwise provided for with independent drive motors with independent frame drives
    • D—TEXTILES; PAPER
    • D03—WEAVING
    • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
    • D03C5/00—Cam or other direct-acting shedding mechanisms, i.e. operating heald frames without intervening power-supplying devices

Definitions

  • the present invention relates to a loom having a plurality of linear motor-driven shedding motion mechanisms so configured as to maintain the conventional arraying pitch between heald frames.
  • a conventional shedding motion of a loom is performed by fixing wires etc. on heald frames and converting the power of an ordinary motor, etc. to a vertical movement using a mechanical mechanism.
  • a mechanical mechanism cams, etc. are used to convert the rotary movement of motors, etc. to a vertical movement.
  • the control of the shedding motion is fixed. Accordingly, the conventional method causes inconvenience when changing the kind of cloth to be woven, since it is not easy to modify the requirements of the shedding motion.
  • the shedding motion of a loom can be controlled by a computer, the speed and timing of the vertical movements of the heald frames can be freely modified, and thereby a loom which can weave various kinds of cloth easily, can be implemented.
  • Figs.1A and 1B explain a conventional linear motor-driven shedding motion mechanism.
  • movement elements 44-1 and 44-2 for linear motors are provided on sidestays 43-1 and 43-2 on each side of a heald frame 42.
  • the movement elements 44-1 and 44-2 are provided on the side of the sidestays 43-1 and 43-2 facing the guide frames 41-1 and 41-2.
  • the guide frames 41-1 and 41-2 are provided with grooves, and the heald frame 42 is set in the grooves.
  • stators 45-1 and 45-2 are provided facing the movement elements 44-1 and 44-2 provided on the heald frame 42.
  • the stators 45-1 and 45-2 are provided with coils to generate a magnetic field.
  • the movement elements 44-1 and 44-2 attached to the sidestays 43-1 and 43-2 of the heald frame 42 are made of aluminum.
  • Fig.1B explains an alternative configuration of the conventional linear motor-driven shedding motion mechanism.
  • a heald frame 46 and guide frames 47-1 and 47-2 being the basic components of the shedding motion mechanism are provided.
  • a part of each of the sidestays 43-1 and 43-2 of the heald frame 46 is set in grooves provided in the guide frames 47-1 and 47-2 to provide vertical movement.
  • linear motors 48-1 and 48-2 are added as shown in Fig.1B.
  • the movement elements of the linear motors 48-1 and 48-2 are attached to supports 49-1 and 49-2, and when the linear motors 48-1 and 48-2 operate, the supports 49-1 and 49-2 move vertically.
  • the linear motors 48-1 and 48-2 are typically cylinder type linear motors.
  • the number of the heald frames provided in a loom is from 4 to 16. It is in order to weave various kinds of patterns into a piece of cloth that a plurality of heald frames are provided. In the case of weaving a piece of cloth which is broad in width, one set of warp threads have to be supported by two heald frames; since the tension of a warp thread becomes high.
  • the pitch between the heald frames is usually set to be approximately 15mm.
  • the angle formed between the warp threads when one heald frame shifts upward and the other heald frame shifts downward, is approximately 30 to 35 degrees. This angle is set so that a weft thread may pass through between upper sheds and lower sheds easily.
  • the stroke (length of a vertical movement) of a heald frame located nearest to the front of the loom is approximately 50mm, and the stroke of a heald frame located farthest from the front of the loom is approximately 140mm.
  • the pitch between heald frames is maintained at approximately 15mm.
  • the maximum thickness of the motors is considered to be over 30 millimeters, even if a linear motor exclusively used for a shedding motion mechanism is developed.
  • the pitch of heald frames is extended to over 30 millimeters, matching the thickness of the linear motors, the stroke of a heald frame located the farthest from the front of a loom out of a plurality of heald frames becomes far longer than 140mm, then a larger propulsive force becomes necessary, and then larger linear motors become necessary, which creates a vicious circle. Accordingly, such a configuration that the pitch between heald frames may be maintained at approximately 15mm under the conditions of using linear motors with a thickness of over 30 millimeters, becomes necessary.
  • the post-published document EP 0 795 635 A1 discloses a configuration similar to Fig. 1B wherein a plurality of heald frames is vertically supported by linear motors. The linear motors of adjacent heald frames are horizontally shifted.
  • Figs.1A and 1B explain conventional linear motor-driven shedding motion mechanisms.
  • Figs.2A through 2C show an embodiment of the heald frame arrays of this invention.
  • Fig.3 shows an comparative example (not claimed) of the arrays in the case of a shedding motion mechanism as shown in Fig.1B.
  • Figs.4A through 4D show alternatives (not claimed) of the arrays of linear motors for a linear motor-driven shedding motion mechanism having a configuration as shown in Fig.3.
  • Figs.2A through 2C show an embodiment of the heald frame arrays of this invention.
  • Fig.2A shows an example of the configuration in the case where heald frames are arrayed diagonally displaced.
  • each heald frame 2 is mounted on a guide frame 5 so as to move vertically, in each end of the heald frame 2 movement elements 4 for forming linear motors are provided, and the movement elements 4 together with stators 3 provided in the guide frame 5 compose a linear motor 1.
  • the difference in configuration between a linear motor shown in Fig.2A and a linear motor shown in Fig.1A, is that in the configuration shown in Fig.2A, the front or rear of a sidestay is used as the effective area for generating propulsive force of the movement elements 4 of a linear motor.
  • the size of the linear motor can be reduced to a minimum.
  • the maximum thickness of the linear motor is considered to be over 30 millimeters. That is, since the propulsive force of a linear motor is determined by the width of the effective area for generating propulsive force, and the thickness is not related with the propulsive force closely, the linear motor can be made thinner.
  • the linear motor becomes too thin, a generated magnetic field saturates the yoke of the linear motor, the propulsive force is reduced, and thereby the coreloss becomes high due to hysteresis. When the coreloss becomes high, the power efficiency of the linear motor falls, and the linear motor becomes heated, which is not desirable.
  • shedding motion mechanisms comprising a linear motor 1, a heald frame 2 and a guide frame 5 are arrayed shifted a little horizontally from each other.
  • linear motors 1 comprising movement elements 4 and stators 3 do not interfere with each other, the pitch between heald frames 2 can be made narrower.
  • Fig.2B shows an alternative heald frame arrangement for preventing linear motors from interfering with each other.
  • heald frames 2 with different horizontal lengths for each shedding motion mechanism are arrayed.
  • the pitch between heald frames can also be made narrow, since linear motors 1 do not interfere with each other.
  • the farther from the front of a loom that a heald frame is located the longer the horizontal length of the heald frame becomes. Accordingly, the farther from the front of a loom a heald frame is located, the larger the size of linear motors for driving the heald frame tends to become.
  • Fig.2C shows an alternative of a heald frame arrangement for arraying shedding motion mechanisms with different horizontal lengths, comprising heald frames 2, guide frames 5 and linear motors 1.
  • a shedding motion mechanism with a plurality of heald frames 2 can be configured without significantly extending the horizontal length, by preparing only two kinds of heald frames with different horizontal lengths. That is, even if many heald frames 2 are used, the overall horizontal length of all of the heald frames is no longer than the horizontal length of the heald frame with the longest horizontal length. Since the horizontal length of the shedding motion mechanism to be used to actually weave cloth does not change even if the number of heald frames 2 increases, the size of heald frames 2 can be reduced to a minimum.
  • Fig.3 shows an comparative example (not claimed) of the arrays in the case of a shedding motion mechanism as shown in Fig.1B.
  • Fig.1B Although the number of linear motors mounted on one heald frame is two in Fig.1B, in Fig.3 four linear motors are mounted on one heald frame 11. By doubling the number of linear motors for driving one heald frame 11 from two to four, the propulsive force needed for each linear motor can be halved, and the size can also be halved.
  • the heald frame 11 As described with reference to Fig.1B, when linear motors 14 are driven with the heald frame 11 supported from the bottom, the heald frame 11 is so mounted as to be able to vertically slide in a guide 13 provided on a guide frame 12. Movement elements 14b of the linear motors 14 are connected to the bottom of the heald frame 11, and are so structured as to move vertically by the force received from the stators 14a.
  • linear motors 14 drawn with solid lines and linear motors 16 drawn with broken lines in the front view of Fig.3 are linear motors for driving a heald frame located nearest to the front and linear motors for driving a heald frame located immediately behind the heald frame nearest to the front, respectively.
  • the linear motors 16 for driving the second nearest to the front heald frame are so located as to avoid the linear motors 14 for driving the nearest to the front heald frame.
  • the linear motors for driving the second nearest to the front heald frame are so located as to avoid the linear motors for driving the nearest to the front heald frame
  • the linear motors for driving the third nearest to the front heald frame are so located as to avoid the linear motors for driving the second nearest to the front heald frame, and so on.
  • Figs.4A through 4D show alternatives (not claimed) of the arrays of linear motors for a linear motor-driven shedding motion mechanism having a configuration as shown in Fig.3.
  • Fig.4A shows a configuration (not claimed) in which linear motors 30-1 and 30-2 for driving a heald frame are mounted vertically.
  • the linear motors for driving a heald frame located at the back are so located as to avoid the linear motors for driving a heald frame located at the front. That is, for example, linear motors 31-1 and 31-2, and linear motors 32-1 and 32-2 are for driving the second heald frame and the third heald frame, respectively.
  • heald frames can be closely arrayed with each other by locating the linear motors for driving a heald frame located behind so as to avoid the linear motors for driving a heald frame in front.
  • Fig.4B shows an example (not claimed) of a shedding motion mechanism in which a configuration of driving a heald frame from the bottom and a configuration of driving a heald frame from the top are alternately arrayed.
  • linear motors 33 are mounted on the bottom of a heald frame located the nearest to the front, and linear motors 34 are mounted on the top of a heald frame located the second nearest to the front. In this way, by alternately mounting linear motors for driving heald frames at the top and then at the bottom, heald frames can be closely located to each other without the linear motors for driving adjacent heald frames interfering with each other.
  • Fig.4C shows a configuration (not claimed) of arraying the linear motors for driving adjacent heald frames in a zigzag pattern. That is, linear motors 35 for driving a heald frame located the nearest to the front and linear motors 36 for driving a heald frame located the second nearest to the front, are positioned offset from each other both horizontally and vertically, with respect to the floor on which the shedding motion mechanism or a loom consisting of these shedding motion mechanisms are installed. As can be clearly seen from the side view of Fig.4C, linear motors for driving the heald frames located the third nearest to the front and subsequent frames, are arrayed in the same way the first two heald frames.
  • Fig.4D shows a configuration (not claimed) in which linear motors are mounted both vertically and arrayed in a zigzag pattern. That is, on a heald frame located the nearest to the front, linear motors 37-1 and 37-2 are mounted vertically. On a heald frame located immediately behind the heald frame nearest to the front, linear motors 38-1 and 38-2 are also mounted vertically. However, the respective mounting positions of the linear motors 38-1 and 38-2 are shifted both horizontally and vertically with respect to the floor, from the corresponding mounting position of linear motors 37-1 and 37-2, so that the linear motors 38-1 and 38-2 may not interfere with the linear motors 37-1 and 37-2.
  • the pitch between a provided plurality of heald frames can be maintained at a conventional pitch.
  • the length of the stroke in the shedding motion of a heald frame located the farthest from the front can be maintained at the same level, and thereby the necessary propulsive force and size of the linear motors can be reduced to a minimum.

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Linear Motors (AREA)
  • Looms (AREA)

Claims (2)

  1. Métier à tisser comprenant une nappe d'une pluralité de cadres de lisses (2) respectivement entraínés, verticalement, le long de cadres de guidage (5) par des moteurs linéaires (1), chacun consistant en un stator (3) et un élément de mouvement (4), respectivement, dans lequel l'un desdits stator (3) et élément de mouvement (4) est prévu dans un renfort latéral, à une extrémité horizontale dudit cadre de lisses (2) et l'autre, respectif, desdits stator (3) et élément de mouvement (4) est prévu dans ledit cadre de guidage (5), caractérisé en ce que lesdits cadres de lisses (2) ont différentes longueurs horizontales de sorte que lesdits moteurs linéaires (1) n'interfèrent pas les uns avec les autres.
  2. Métier à tisser selon la revendication 1, caractérisé en ce que les cadres de lisses (2) sont placés en une nappe décalée horizontalement.
EP19980108242 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire Expired - Lifetime EP0879909B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP02003317A EP1215318A2 (fr) 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP11801597 1997-05-08
JP11801597A JPH10310949A (ja) 1997-05-08 1997-05-08 リニアモータ式開口装置を有する織機
JP118015/97 1997-05-08

Related Child Applications (1)

Application Number Title Priority Date Filing Date
EP02003317A Division EP1215318A2 (fr) 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire

Publications (2)

Publication Number Publication Date
EP0879909A1 EP0879909A1 (fr) 1998-11-25
EP0879909B1 true EP0879909B1 (fr) 2002-09-04

Family

ID=14725957

Family Applications (2)

Application Number Title Priority Date Filing Date
EP02003317A Withdrawn EP1215318A2 (fr) 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire
EP19980108242 Expired - Lifetime EP0879909B1 (fr) 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP02003317A Withdrawn EP1215318A2 (fr) 1997-05-08 1998-05-06 Métier à tisser avec dispositif de formation de la foule entrainé par moteur linéaire

Country Status (3)

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EP (2) EP1215318A2 (fr)
JP (1) JPH10310949A (fr)
DE (1) DE69807572T2 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3538137B2 (ja) * 2000-10-23 2004-06-14 津田駒工業株式会社 織機における開口装置
DE10111017B4 (de) 2001-03-07 2006-02-02 Lindauer Dornier Gmbh Antrieb für die Webschäfte einer Webmaschine
DE102004006389B4 (de) 2004-02-10 2007-05-31 Groz-Beckert Kg Fachbildeeinrichtung für eine Webmaschine
ES2267029T3 (es) * 2004-03-02 2007-03-01 Promatech S.P.A. Telar con marcos accionados por motor.
WO2005098109A1 (fr) * 2004-04-07 2005-10-20 Rohit Verma Metier a tisser electronmagnetique
DE102006059879A1 (de) 2006-12-19 2008-07-03 GÖRGENS, Detlef Webmaschine mit Direktantrieb für Schäfte und Weblade (D03C)
ATE456692T1 (de) * 2007-07-26 2010-02-15 Luigi Omodeo Zorini Nadelwebmaschine
JP5095316B2 (ja) * 2007-09-05 2012-12-12 東芝機械株式会社 織機及び織機の駆動装置。
DE202008006567U1 (de) 2008-05-15 2008-08-14 Lehmann, Michael, Dipl.-Ing. Elektromotorischer Einzelschaftantrieb
CN106868680B (zh) * 2017-04-07 2018-08-17 杨国惠 一种平衡综框静力、惯性力的开口机

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1105933B (it) * 1977-07-26 1985-11-11 Brochier Soieries J Apparecchiatura per il comando dei movimenti dei fili di ordito in un telaio di tessitura
JPS59192749A (ja) * 1983-04-11 1984-11-01 株式会社豊田自動織機製作所 織機の開口装置
GB8817765D0 (en) * 1988-07-26 1988-09-01 Palmer R L Loom control
EP0795635B1 (fr) * 1996-03-14 2001-06-27 Sulzer Textil AG Dispositif de formation de la foule et métier à tisser pourvu d'un tel dispositif
JPH09268451A (ja) * 1996-03-27 1997-10-14 Toyota Autom Loom Works Ltd 織機における開口装置

Also Published As

Publication number Publication date
DE69807572T2 (de) 2003-01-16
EP1215318A2 (fr) 2002-06-19
DE69807572D1 (de) 2002-10-10
EP0879909A1 (fr) 1998-11-25
JPH10310949A (ja) 1998-11-24

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