US3734422A - Apparatus for monitoring yarn at winders - Google Patents

Apparatus for monitoring yarn at winders Download PDF

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Publication number
US3734422A
US3734422A US00143777A US3734422DA US3734422A US 3734422 A US3734422 A US 3734422A US 00143777 A US00143777 A US 00143777A US 3734422D A US3734422D A US 3734422DA US 3734422 A US3734422 A US 3734422A
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United States
Prior art keywords
yarn
interrogation
bobbin
travel
signal
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Expired - Lifetime
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US00143777A
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English (en)
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E Loepfe
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Loepfe AG Gebrueder
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Loepfe AG Gebrueder
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H63/00—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package
    • B65H63/02—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material
    • B65H63/024—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials
    • B65H63/028—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials characterised by the detecting or sensing element
    • B65H63/032—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials characterised by the detecting or sensing element electrical or pneumatic
    • B65H63/0321—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to reduction in material tension, failure of supply, or breakage, of material responsive to breakage of materials characterised by the detecting or sensing element electrical or pneumatic using electronic actuators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2701/00—Handled material; Storage means
    • B65H2701/30—Handled filamentary material
    • B65H2701/31—Textiles threads or artificial strands of filaments

Definitions

  • the present invention relates to a new and improved apparatus for monitoring a yarn at a winder, especially an automatic cross-winder machine.
  • condition of the yarn first of all is intended to denote the presence of absence of the stationary yarn within a given spatial area, and secondly, additionally denotes the movement or standstill of a yarn in the direction of the lengthwise axis of the yarn.
  • the heretofore known control mechanisms generally use different devices for checking the presence-nonpresence of the stationary yarn (so-called yarn presence monitors) and for monitoring lengthwise movement-standstill of the yarn (so-called yarn travel monitors").
  • Certain of the state-of-the-art yarn travel monitors incorporate pivotable mechanical brackets which are retained in a given position by the traveling yarn LII owing to its rigidity and tension, the brackets being held, as explained above, by the yarn in such predetermined position against the action of a restoring force of a spring. Should the yarn rupture then the bracket will be pivoted by the action of the spring.
  • the need to perform delicate adjustments, the presence of frequent binding and other defects have resulted in the manufacture of improved yarn travel monitors which usually are electronic in nature.
  • These electronic yarn travel monitors either employ a yarn travel signal which is generated as a function of the roughness and irregularity of the yarn surface during yarn travel, or else, for instance, a yarn travel signal which is generated by virtue of the traversing motion occurring during the winding operation
  • Suitable as yarn presence monitors are mechanical feelers in the form of bifurcated or forked members, rakes, needles and the like which are blocked in movement by a stationary yarn which is present.
  • these type monitors likewise are subject to the disadvantages of requiring critical adjustments, frequent binding and unreliable operation when working with thin yarns.
  • a primary object of this invention is to provide just such apparatus which effectively and reliably fulfills the existing need in the art.
  • Another and more specific object of the present invention relates to a new and improved construction of apparatus for monitoring the yarn of a winding machine, especially a cross-winder, which is relatively simple in construction, extremely reliable in operation, not readily subject to breakdown, and affords accurate and efficient monitoring operations.
  • such type transducer can perform both the function of the yarn travel monitor as well as that of the yarn presence monitor at an automatic cross-winder.
  • Tribo electrical yarn monitors and transducers suitable for the purposes of the present invention are well known to the art, as for instance disclosed in Swiss Pat. 479,478 and in my commonly assigned, co-pending United States application, Ser. No. 833,030, filed June 13, 1969, now U.S. Pat. No. 3,676,769 and entitled Method And Apparatus For Detecting A Relative Movement Between Two Bodies Being In Contact With Each Other," and to which reference may be readily had.
  • Such type transducer which can be used as a yarn feeler preferably encompasses a friction element, an electrode and a housing formed of electrically conductive material and serving as a screening element.
  • the traveling yarn produces potential or voltage fluctuations at the friction body or element which is preferably formed, for instance, or ceramic, these potential fluctuations being delivered through the agency of the electrode to an amplifier, the output signal of which has the form of a noise voltage.
  • An integrator shapes such output signal into a directcurrent voltage signal possessing a well defined amplitude, and a subsequently connected Schmitt-trigger ensures that the beginning as well as the end of the yarn signal is well defined. With the yarn traveling there prevails at the output of the entire arrangement the binary potential one, i.e., the logical signal 1, and with the yarn stationary the binary potential null, i.e., the logical signal 0.
  • a preferred physical manifestation of the inventive apparatus contemplates the provision of a tribo electrical transducer for determining the presence of a stationary yarn, an interrogation mechanism which is operably associated with the yarn, and means for actuating the interrogation mechanism when the speed of travel of the yarn has fallen below a predetermined boundary or threshold value, so that the interrogation mechanism produces a relative movement between the transducer and the yarn which is sufficient for generating a response signal by the transducer.
  • the tribo electrical transducer is employed as the yarn presence monitor and simultaneously, consistent with its known function, as the yarn travel monitor for controlling the winder.
  • the tribo electrical transducer also delivers a signal which can be exceptionally well evaluated even at very low yarn travel speeds beneath m/min.
  • the presence of a stationary yarn is determined in that there is generated a slight relative movement between the yarn and the friction body of the tribo electrical transducer.
  • This can be realized, for instance, by a slight forced movement of the yarn, for instance by briefly starting-up the cross-wound bobbin or by performing a slight sudden deflection of the yarn out of its normal position.
  • the apparatus therefore, apart from being used for the function of a yarn travel monitor, additionally can assume in the most simple fashion the function of a positively functioning yarn presence monitor.
  • FIG. 1 is a schematic circuit diagram of a first embodiment of the invention
  • FIG. 2 is a graph serving to explain the associated curve or diagram of the electrical pulses, wherein the null or zero line has been illustrated broken;
  • FIG. 3 is a second embodiment of the inventive apparatus which has been modified somewhat from the embodiment of FIG. ll.
  • An electronic circuit 4 is coupled with the tribo electrical transducer 3, and an evaluation circuit 13 is electrically coupled in turn with this electronic circuit 4.
  • the latter delivers tribo electrical signal to the electronic circuit 4 which as a result delivers a continuous direct-current voltage signal characterizing a yarn travel signal 7, as best seen by referring to FIG. 2.
  • the yarn 1 should rupture for some reason then this signal disappears, a null potential 8 then appearing at the output of the electronic circuit 4.
  • the trailing edge 9 of the signal characterized yarn rupture or disappearance.
  • the trailing edge signal actuates an electromagnet 10 by means of which the drive means (not shown) of the cross-wound package 6 is brought to standstill.
  • the trailing edge signal 9 further actuates a different electromagnet 11 equipped with an interrogation element 11' by means of which the lower yarn portion situated at the region of the transducer 3 is somewhat deflected.
  • the interrogation element or member 11 is operatively connected with the movable armature 11a of the electromagnet 11.
  • the electronic circuit 4 will be understood to contain a number of conventional electrical circuits, the details of which are not essential to the understanding of the invention since it will be apparent that suitable circuits of this nature are already well known in the art. Therefore, as schematically indicated in FIG. 1 electronic circuit 4 will be seen to embody a conventional amplifier circuit 4a, a conventional rectifier and smoothing circuit 4b, such as an integrator circuit for instance, and a conventional signal shaper circuit 4c, for instance a Schmitt-trigger.
  • a conventional amplifier circuit 4a a conventional rectifier and smoothing circuit 4b, such as an integrator circuit for instance
  • a conventional signal shaper circuit 4c for instance a Schmitt-trigger.
  • the electronic circuit 4 produces a trailing edge signal 9 and a response pulse 12 as described above and shown in FIG. 2.
  • the trailing edge signal 9 of the yarn travel signal 7 triggers a monostable multivibrator 14 which delivers an interrogation pulse 15.
  • the multivibrator 14 is designed and dimensioned such that the interrogation pulse 15 encompasses in time the response pulse 12 of the electronic circuit 4, sometimes hereinafter referred to as transducer circuit 4.
  • the pulses 12 and are delivered to an AND-gate 16 which, in turn, delivers a control pulse 17 to an electromagnet 18 when, during the presence of the interrogation pulse 15 there arrives the response pulse 12, that is to say, when the lower yarn portion is intact.
  • Electromagnet 18 then places the drive means (not shown) of an automatic knotter into operation.
  • the control pulse 17 further triggers the monostable multivibrator 19, at the output of which there normally exists the potential one so that a null pulse is produced.
  • the monostable multivibrator 19 is designed and dimensioned such that the null pulse 20 encompasses in time the descending flank 21 of the interrogation pulse 15.
  • the interrogation pulse 15 is also delivered to a monostable multivibrator 28 which as a result delivers a second control pulse 22.
  • the null pulse 20 and the second control pulse 22 derived from the descending flank 21 of the interrogation pulse 15 by means of a monostable multivibrator 28 are delivered to an AND-gate 23.
  • the second control pulse 22 cannot pass this gate, and the electromagnet 24 is not actuated.
  • a trailing edge signal 9 an interrogation pulse 15 and a control pulse 22 are produced, however, there will be no response pulse 12, and no control pulse 17 and null pulse 20. That means that the electromagnet 18 is not actuated, however, the second control pulse 22 passes the AND-gate 23 as an indication that the lower yarn portion is not intact. The second control pulse 22 therefore actuates the electromagnet 24 to start up the drive means (not shown) of an automatic exchange mechanism serving to exchange the delivery cop.
  • the tribo electrical transducer 3 is arranged above the yarn brake 5 and therefore is operably associated with the upper yarn portion.
  • a non-illustrated mechanism of any conventional construction and therefore not shown measures continuously the degree of filling of the cross-wound bobbin or package 6. It is here to be assumed for instance that this mechanism has just sensed and indicated that the bobbin 6 has just reached a fully wound package condition and that as a result thereof the drive for such cross-wound bobbin is interrupted, for instance by raising the aforesaid cross-wound bobbin from the driving grooved drum of conventional design and therefore likewise not shown.
  • the decision whether a knotting operation should be performed or whether the cross-wound package or bobbin should be exchanged can be determined by the tribo electrical yarn monitor of FIG. 3 and consisting of the transducer 3 and the electronic circuit 4, in the following manner: the trailing edge signal 9 of the yarn travel signal 7 (FIG. 2) signifies either a yarn rupture or the standstill of the cross-wound bobbin with the yarn still intact.
  • the descending trailing edge signal 9 actuates an interrogation element, here in the form of the interrogation magnet 25 which, with the arrangement according to the embodiment of FIG. 3, re-
  • the AND-gate l6 delivers a control pulse 17 to the electromagnet 26 which places the automatic servicing or tending mechanism of the cross-wound bobbin into operation.
  • the AND-gate 23 delivers a control pulse 22 to the electromagnet 27 which places into operation the automatic knotter.
  • FIGS. 1 and 3 can be modified, of course, in a number of different ways.
  • a mechanical yarn monitor is already provided for at the winder and of the type incorporating a yarn feeler lever
  • shutdown of the wind-up bobbin or cross-wound bobbin and the actuation of an interrogation element can be brought about by the yarn feeler lever.
  • the interrogation movement can be transmitted to an interrogation element corresponding to element 11 by means of mechanical intermediate elements arranged between the yarn feeler lever and the interrogation element.
  • An apparatus for monitoring a yarn at a winder comprising a tribo electrical transducer means for determining the presence of a stationary yarn, an interrogation mechanism operably associated with the yarn, and means for actuating the interrogation mechanism when the speed of travel of the yarn has fallen below a predetermined threshold value so that the interrogation mechanism can produce a relative movement between the transducer means and the yarn which is sufficient for generating a response signal by said transducer means.
  • said interrogation mechanism comprises a mechanical element positively acting upon the yarn.
  • said interrogation mechanism comprises electromagnetic means actuated by an electrical trigger signal, said electromagnetic means incorporating a movable armature capable of positively acting upon the yarn.
  • said winder incorporates a driven wind-up bobbin
  • said means serving to actuate said interrogation mechanism comprises an electronic circuit with which said transducer means cooperates, said electronic circuit delivering a continuous yarn travel signal when the yarn is moving, said yarn travel signal possessing a trailing edge when the yarn is broken or has run out serving to stop the wind-up bobbin and serving as trigger signal for the interrogation mechanism.
  • said electronic circuit embodies an amplifier circuit followed by a rectifier circuit and a pulse shaper circuit so that there is produced a direct-current voltage signal serving as the yarn travel signal and having a welldefined trailing edge.
  • the apparatus as defined in claim 6, further including an actuation mechanism for initiating a knotting operation or bobbin change operation, an evaluation circuit operatively connected with said electronic circuit, said evaluation circuit upon the occurrence of a response signal, following a trigger signai delivered by the electronic circuit, delivers at least one control signal for actuating said actuation mechanism for the knotting operation or bobbin change operation.
  • said evaluation circuit comprises an AND-gate having a pair of inputs, one of said inputs directly being connected with the output of said electronic circuit and the other input being connected through the agency of a monostable multivibrator with the output of said electronic circuit.
  • the apparatus as defined in claim 8, further including a delivery cop and a winding unit where the yarn delivered from said delivery cop through a given path of travel is wound as a yarn package, a yarn brake disposed intermediate said delivery cop and said winding unit in the path of travel of the yarn between said delivery cop and said winding unit, a first actuation mechanism in circuit with said evaluation circuit for carrying out a knotting operation and a second actuation mechanism in circuit with said evaluation circuit for carrying out exchange of the delivery cop, said transducer means and said interrogation mechanism being effective at the region of the lower portion of the yarn prior to entry into said yarn brake, and upon occurrence of a response signal said first actuation mechanism for the knotting operation is triggered and upon absence of the response signal following a yarn travelterminal signal there is actuated the second actuation mechanism for the exchange of the delivery cop.
  • the apparatus as defined in claim 8, further including a delivery cop and a winding unit, said delivery cop serving to supply yarn along a predetermined path of travel to the winding unit to wind the yarn thereat in the form of a full-wound bobbin, a yarn brake disposed intermediate said delivery cop and said winding unit at said predetermined path of travel, a first actuation mechanism for exchanging the wound bobbin, a second actuation mechanism for initiating a knotting operation, said transducer means and said interrogation mechanism being effective at the region of the upper portion of the yarn after passing said yarn brake, and upon occurrence of a response signal after stopping the full-wound bobbin said first actuation mechanism for carrying out exchange of the full wound bobbin is triggered, and upon the absence of a response signal after placing the wound bobbin into a standstill condition said second actuation mechanism is triggered for carrying out a knotting operation.

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Filamentary Materials, Packages, And Safety Devices Therefor (AREA)
  • Replacing, Conveying, And Pick-Finding For Filamentary Materials (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
US00143777A 1970-05-28 1971-05-17 Apparatus for monitoring yarn at winders Expired - Lifetime US3734422A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH801170A CH526459A (de) 1970-05-28 1970-05-28 Einrichtung zur Überwachung eines Fadens, der von einer Ablaufstelle zu einer Auflaufstelle geführt ist

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US3734422A true US3734422A (en) 1973-05-22

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US00143777A Expired - Lifetime US3734422A (en) 1970-05-28 1971-05-17 Apparatus for monitoring yarn at winders

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US (1) US3734422A (de)
JP (1) JPS5035574B1 (de)
CH (1) CH526459A (de)
DE (1) DE2124288C3 (de)
FR (1) FR2093807A5 (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3863241A (en) * 1972-03-25 1975-01-28 Yamatake Honeywell Co Ltd A yarn break detector utilizing a sensor for sensing the yarn static electricity
DE2619430A1 (de) * 1976-05-03 1977-11-24 Schlafhorst & Co W Vorrichtung zur ueberwachung des fadenlaufs
US4202506A (en) * 1976-05-03 1980-05-13 W. Schlafhorst & Co. Device for monitoring thread travel
US4214717A (en) * 1975-06-10 1980-07-29 Nippon Seren Co. Ltd. False reeling preventing apparatus for traverse thread reeling machines
US4256247A (en) * 1977-10-05 1981-03-17 Gebruder Loepfe Ag Device for monitoring yarn motion on a textile machine
US4807829A (en) * 1988-02-18 1989-02-28 Otto Zollinger, Inc. Combined yarn tensioning control and stop motion unit
US5725165A (en) * 1993-07-17 1998-03-10 W. Schlafhorst Ag & Co. Method of monitoring the moving yarn at a winding station of an automatic winding frame

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5040573U (de) * 1973-08-06 1975-04-24
DE2543281C2 (de) * 1975-09-27 1985-08-01 W. Schlafhorst & Co, 4050 Mönchengladbach Vorrichtung zur Außerbetriebnahme einer Wickeleinrichtung bei Fadenbruch
JPS57184072A (en) * 1981-04-13 1982-11-12 Murata Mach Ltd Doffing controller in automatic winders
DE3603649A1 (de) * 1986-02-06 1987-08-13 Baer Maschf Josef System zur ueberwachung der fadenzufuehrung bei wickelmaschinen, insbesondere fuer die roving-wickeltechnik
DE4323994C2 (de) * 1993-07-17 2001-02-22 Schlafhorst & Co W Verfahren zum Überwachen des laufenden Fadens an einer Spulstelle einer automatischen Spulmaschine
EP2108949A1 (de) 2005-06-15 2009-10-14 Uster Technologies AG Verfahren und Vorrichtung zur Erkennung von Fremdstoffen in einem bewegten, festen, länglichen Prüfgut

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3304015A (en) * 1963-04-19 1967-02-14 Schweiter Ag Maschf Method and apparatus for the processing of undesired yarn conditions appearing at an automatic winding machine
US3358941A (en) * 1964-06-29 1967-12-19 Schweiter Ag Maschf Yarn remainder feeler
US3405877A (en) * 1965-05-05 1968-10-15 Schweiter Ag Maschf Method and apparatus for the treatment of ejected delivery bobbins
US3476329A (en) * 1965-07-06 1969-11-04 Zellweger Uster Ag Apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3304015A (en) * 1963-04-19 1967-02-14 Schweiter Ag Maschf Method and apparatus for the processing of undesired yarn conditions appearing at an automatic winding machine
US3358941A (en) * 1964-06-29 1967-12-19 Schweiter Ag Maschf Yarn remainder feeler
US3405877A (en) * 1965-05-05 1968-10-15 Schweiter Ag Maschf Method and apparatus for the treatment of ejected delivery bobbins
US3476329A (en) * 1965-07-06 1969-11-04 Zellweger Uster Ag Apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3863241A (en) * 1972-03-25 1975-01-28 Yamatake Honeywell Co Ltd A yarn break detector utilizing a sensor for sensing the yarn static electricity
US4214717A (en) * 1975-06-10 1980-07-29 Nippon Seren Co. Ltd. False reeling preventing apparatus for traverse thread reeling machines
DE2619430A1 (de) * 1976-05-03 1977-11-24 Schlafhorst & Co W Vorrichtung zur ueberwachung des fadenlaufs
US4202506A (en) * 1976-05-03 1980-05-13 W. Schlafhorst & Co. Device for monitoring thread travel
US4256247A (en) * 1977-10-05 1981-03-17 Gebruder Loepfe Ag Device for monitoring yarn motion on a textile machine
US4807829A (en) * 1988-02-18 1989-02-28 Otto Zollinger, Inc. Combined yarn tensioning control and stop motion unit
US5725165A (en) * 1993-07-17 1998-03-10 W. Schlafhorst Ag & Co. Method of monitoring the moving yarn at a winding station of an automatic winding frame

Also Published As

Publication number Publication date
JPS5035574B1 (de) 1975-11-17
DE2124288B2 (de) 1977-09-29
DE2124288C3 (de) 1978-05-18
FR2093807A5 (de) 1972-01-28
DE2124288A1 (de) 1971-12-09
CH526459A (de) 1972-08-15

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