US3476329A - Apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners - Google Patents

Apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners Download PDF

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Publication number
US3476329A
US3476329A US557483A US3476329DA US3476329A US 3476329 A US3476329 A US 3476329A US 557483 A US557483 A US 557483A US 3476329D A US3476329D A US 3476329DA US 3476329 A US3476329 A US 3476329A
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United States
Prior art keywords
yarn
signal
speed
voltage
traveling
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Expired - Lifetime
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US557483A
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English (en)
Inventor
Ernst Felix
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Zellweger Uster AG
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Zellweger Uster AG
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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
    • B65H61/00—Applications of devices for metering predetermined lengths of running material
    • B65H61/005—Applications of devices for metering predetermined lengths of running material for measuring speed of running yarns
    • 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
    • B65H63/06—Warning or safety devices, e.g. automatic fault detectors, stop-motions ; Quality control of the package responsive to presence of irregularities in running material, e.g. for severing the material at irregularities ; Control of the correct working of the yarn cleaner
    • B65H63/062—Electronic slub detector
    • 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

  • This invention relates to an apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners. More particularly, this invention relates to an apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners during running in of winding spindles.
  • Electronic yarn cleaners capable of removing coarse yarn from a traveling yarn usually locate the coarse yarn by producing an electric signal corresponding to the yarn cross section in a measuring apparatus through which the yarn travels. The signal is then passed through a low-pass filter in order to eliminate short periodic variations and pass on only a long periodic signal which char acterizes the coarse yarn.
  • this requires a certain minimal traveling speed of the yarn at a given cutotf frequency of the low-pass filter.
  • the cross wound bobbin starts and runs out slowly, the yarn travels at a speed less than the minimal traveling speed so that short periodic signal variations due to short periodic variations in the cross section of the yarn are also passed by the low-pass filter.
  • the invention relates to an apparatus and method for avoiding unnecessary cutting of a traveling yarn by electronic yarn cutters in removing coarse sections of yarn.
  • the invention measures the speed of a yarn during travel through an electronic yarn cleaner and regulates the sensitivity of the yarn cleaner in relation to the measured yarn speed. This results in the yarn cleaner cutting only the undesirable coarse sections of yarn from the traveling yarn as the signal amplitudes relating to the sections of yarn having short periodic variations in yarn cross section are prevented from bypassing the low-pass filter during starting and runout periods.
  • the invention is utilized with an electronic yarn cleaner having a measuring device for producing a signal proportional to the cross section of a yarn traveling through the cleaner, a switch stage for receiving the produced signal having elements for adjusting the sensitivity of the yarn cleaner to produce an output signal corresponding to excessive yarn cross sections and a cutting device for cutting the traveling yarn in response to the delivered signal exceeding a predetermined value.
  • the invention includes a speed discriminator means for measuring the speed of the yarn traveling through the yarn cleaner which is operatively connected to the elements of the switch stage for regulating the elements in relation to the measured speed of the traveling yarn.
  • the speed of the yarn is measured by measuring the rotational speed of a bobbin spooling up the traveling yarn or by measuring the frequencies of the signal produced by the measuring device of the yarn cleaner.
  • FIG. 1 illustrates a schematic of an electronic yarn cleaner incorporating the invention
  • FIG. 2 illustrates a perspective view of one form of the invention wherein the rotational speed of a bobbin cam cylinder is measured
  • FIG. 3 illustrates a circuit utilized in the structure shown in FIG. 2;
  • FIG. 4 illustrates a circut of a modification wherein the frequencies of the yarn measuring of the invention signal are measured
  • FIG. 5 illustrates a circuit of another modification of the invention
  • FIG. 6 illustrates a circuit of the switch stage and cutting device as connected to the measuring apparatus and speed discriminator of FIG. 1;
  • FIG. 7 illustrates a circuit similar to FIG. 6 wherein the speed discriminator is operably connected to the measuring apparatus.
  • an electric signal U proportional to the thickness of the yarn is produced by the measuring apparatus 2 in the conventional manner.
  • the signal is then directed to a switch stage 3 comprising elements for adjusting the sensitivity of the yarn cleaner.
  • the switch stage 3 is connected to an output stage 4, such as, a cutting device, to deliver a signal thereto for instigating the cutting of the yarn when the measured thickness of the traveling yarn 1 is greater than desired.
  • a speed discriminator 5 which measures the speed of the traveling yarn 1 is operatively connected to the elements of switch stage 3 which adjust the sensitivity of the yarn cleaner for regulating the elements.
  • a yarn speed discriminator 5 is controlled in response to the speed or r.p.m. of a cam cylinder 6 driving a bobbin 7 by a contact or switch mechanism 8 which is actuated, for example, by being closed, at least once for each revolution of the cam cylinder 6.
  • the circuit of the discriminator includes a storage condenser 10 which is charged over a charging resistance 11 to an auxiliary voltage U when the contact 8 is open.
  • the contact 8 is intermittently closed during rotation of the cylinder 6, the circuit shorts and the charge accumulated in the condenser 10 is exhausted so that the voltage U collapses. The voltage U increases again when the switch 8 is opened.
  • a voltage U corresponding to the medium value of the voltage U is produced by means of a resistor 12 and a condenser 13 suitably arranged in the discriminator circuit.
  • the voltage U which is relatively small at normal speeds of the cylinder 6 and which increases at starting up and running out of the cross wound bobbin 7, provides a signal to actuate the elements adjusting the sensitivity of the yarn cleaner in the conventional manner. This actuation may be continuous or stepwise whereby the voltage U actuates, for example, a level switch, known per se, Which controls the sensitivity of the yarn cleaner.
  • the speed of travel of the yarn can be transferred into an electric signal for the discriminator by measuring the rotational speed of the cross Wound bobbin 7 and feeding the measurement into the discriminator 5.
  • Another manner of forming an electric signal corresponding to the speed of travel of the yarn 1 is the direct use of the signal U
  • the amplitudes of short periodic variations are considerably greater than those of the long periodic variations.
  • the maximal amplitude of the signal corresponding to periodic variations of the thickness of the yarn is associated with a wave length of two to three times the staple length. Since the amplitude decreases considerably towards the short wave lengths, and since the amplitudes of the shorter periodic thickness variations are further reduced because of the finite length of the measuring field of the apparatus 2, the frequencies of a signal U which correspond to the periodic variations of the thickness of yarn with two to three times the staple length dominate. It is noted that a decrease of the amplitude of the periodic variations of the thickness of the yarn can also be observed at greater wave lengths.
  • the signal or voltage U can therefore be fed to a frequency discriminator which produces a corresponding output signal in a conventional manner.
  • the circuit of a velocity discriminator can be modified with a transistor 23 which is short circuited with a current flowing through a resistor 22 so that a voltage U, is zero in the state of rest.
  • a signal voltage U arrives at the base of the transistor 23 through a frequency-dependent resistance-condenser (RC) element comprising a condenser 20 and a resistor 21, the transistor 23 is at least partly opened whereby the voltage U slowly increases.
  • RC resistance-condenser
  • the frequencies of U are low and the voltage U increases slowly.
  • the frequencies of U are high so that the voltage U; increases at a considerable rate.
  • the voltage U can be made to act on the elements which adjust the sensitivity of the yarn cleaner.
  • another modified discriminator circuit may be used wherein this latter condition is not required, assuming that U is always high.
  • a condenser 27 is connected to the collector of the transistor 23 over a diode 26 in order to prevent a great increase of the voltage U when starting and running up. Therefore, when the first pulses of U arrive, the condenser 27 is charged over a resistor 28 before the voltage U; increases noticeably.
  • the charging time constant of the condenser 27 is chosen over the resistor 28 so that the increase of the voltage U, requires a time interval which is approximately equal to that required by the cam drum 6 for running up to normal operating speed of the yarnpassage.
  • the pulsat ing voltage at the collector of the transistor 23 is also smoothed by means of a resistor 12 and a condenser 13.
  • the signal U from the measuring apparatus 2 is conveyed through a capacitor to a potentiometer 31 in the switch stage 3.
  • the output signal U U from the speed discriminator 5 is conducted to a terminal 30 of the switch stage 3 and fed over a resistor to the same terminal of the potentiometer as the signal U
  • U represents an AC voltage which passes the coupling condenser
  • signals U or U respectively represent DC voltages which give the bias for a transistor 32.
  • This bias is adjustable by the potentiometer setting and controls, therefore, the sensitivity of the circuit.
  • the voltage taken from the potentiometer 31 actuates a Schmitt-trigger of known construction which consists of the transistors 32, 33 with associated resistors.
  • the Schmitt-trigger When the voltage U or U is small, the Schmitt-trigger is less sensitive than in the case when the voltage is higher. Similarly, the Schmitt-trigger is also less sensitive than the tap of the potentiometer 31 is in a lower or higher position.
  • the output pulses from the Schmitt-trigger are fed through a blocking capacitor 34 to an output terminal 35 connected to the output stage 4.
  • the output stage 4 has an input terminal 40 which connects to the output terminal 35 of the switch stage 3.
  • the pulses received from the switch stage 3 via the terminal 40 control a multivibrator of known construction with transistors 41, 42.
  • a power stage in the output stage 4 having a transistor 43 is connected to a coil 44 in the electrical circuit of a cutter to energize the coil 44.
  • the coil 44 attracts the armature 45 which in turn pushes the slider 46 of the cutter with the cutting edge against an abutment 47. Since the yarn 1 travels in a path between the cutting edge of the slider 46 and the abutment 47, the yarn 1 becomes severed upon energization of the coil 44.
  • the cutter is of known construction, for example, as shown in US. Patent 3,322,013 and therefore is not further described.
  • the circuit is similar to that shown in FIG. 6 and need not be further described. However, as shown, the speed discriminator S is supplied directly from the measuring apparatus 2 with the signal U The operation of the switch stage 3 and output stage 4 is similar to that described above in FIG. 6.
  • a speed discriminator means for measuring the speed of the yarn traveling through the yarn cleaner, said speed discriminator being operatively connected to the elements in the switch stage for regulating the elements to adjust the sensitivity of the yarn cleaner in relation to the measured speed of the traveling yarn whereby unnecessary cuts in the traveling yarn are avoided during run-up and run-down of the yarn.
  • said speed discriminator means includes an electrical circuit for producing a signal in response to the measured speed of the traveling yarn, said circuit having a switch mechanism operably connected to said cam cylinder for intermittent actuation in response to each revolution thereof, a storage condenser arranged in parallel with said switch mechanism for shorting the circuit upon closing of said switch to produce a voltage to regulate the elements of the switch stage and an auxiliary signal means for charging said condenser.
  • said discriminator means includes a circuit having a transistor for receiving the produced signal, a resistor for short circuiting said transistor, a frequency-dependent resistance-condenser element including a condenser and a second resistor for passing the produced signal to said transistor for at least partly opening said transistor to produce an increasing voltage output for regulating the elements of the switch stage in response to the frequencies of the produced signal.
  • said circuit further includes a series resistor and condenser means for obtaining the medium value of the voltage intermittently prevailing at said transistor for smoothing said voltage.
  • said circuit further includes a retarding means for preventing an excessive voltage output increase upon running up of the traveling yarn, said retarding means including a diode connected on one side to the collector of said transistor, a second condenser connected to the other side of said diode and a third resistor connected between said diode and second condenser for charging said second condenser.
  • a method of adjusting the sensitivity of'an electronic yarn cleaner for avoiding unnecessary cutting of a traveling yarn comprising the steps of measuring the speed of the traveling yarn through the electronic yarn cleaner, regulating the sensitivity of the electronic yarn cleaner in response to the measured speed of the traveling yarn whereby unnecessary cuts in the traveling yarn avoided during run-up and run-down of the yarn.
  • step of measuring the yarn speed includes measuring the rotational speed of a bobbin spooling up the traveling yarn which rotational speed is proportional to the yarn speed through the electronic yarn cleaner.
  • a method as set forth in claim 7 wherein said step of measuring the speed of traveling yarn includes producmg a signal proportional to the yarn cross section, and
  • a method as set forth in claim 9 which further includes the step of smoothing said output signal.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Quality & Reliability (AREA)
  • Filamentary Materials, Packages, And Safety Devices Therefor (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
US557483A 1965-07-06 1966-06-14 Apparatus and method for avoiding unnecessary cuts by electronic yarn cleaners Expired - Lifetime US3476329A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH948165A CH422603A (de) 1965-07-06 1965-07-06 Verfahren und Vorrichtung zur Vermeidung von unbegründeten Schnitten durch elektronische Garnreiniger beim Anlauf und Auslauf von Spulspindeln

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US3476329A true US3476329A (en) 1969-11-04

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US (1) US3476329A (de)
AT (1) AT276170B (de)
BE (1) BE681707A (de)
CH (1) CH422603A (de)
DE (1) DE1560640B1 (de)
GB (1) GB1093315A (de)
NL (1) NL6604683A (de)
SE (1) SE313199B (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3631354A (en) * 1969-03-05 1971-12-28 Schweiter Ag Maschf Apparatus for the automatic adjustment of a yarn cleaner
US3643882A (en) * 1970-03-09 1972-02-22 Lessona Corp Yarn handling
US3673591A (en) * 1969-11-06 1972-06-27 Peyer Siegfried Yarn defect detector apparatus for textile machinery
US3734422A (en) * 1970-05-28 1973-05-22 Loepfe Ag Geb Apparatus for monitoring yarn at winders
US3758216A (en) * 1971-05-27 1973-09-11 Loepfe Ag Geb Electronic appliance for setting and checking electronic yarn clearers
US3774860A (en) * 1970-05-28 1973-11-27 Laepfe Ag Geb Apparatus for evaluating the winding speed of cross-winders
US3844498A (en) * 1970-05-28 1974-10-29 Loepfe Ag Geb Apparatus for evaluating the winding speed of cross-winders
US3860185A (en) * 1973-12-28 1975-01-14 Nippon Selen Co Ltd Rotation detector in a fixed length yarn winding apparatus
US4036445A (en) * 1974-05-15 1977-07-19 Aktiengesellschaft Gebruder Loepfe Circuit arrangement for monitoring the operation of an electronic yarn clearer
US4292868A (en) * 1979-03-08 1981-10-06 Maschinenfabrik Schweiter Ag Textile spooling machine, an apparatus and method to prevent the formation of loose cut thread pieces
US4512526A (en) * 1981-04-13 1985-04-23 Murata Kikai Kabushiki Kaisa Doffing control system in automatic winder
DE3611263A1 (de) * 1985-04-05 1986-10-16 Murata Kikai K.K., Kyoto Verfahren zum steuern einer spulstelle und spulautomat mit einer steuerschaltung
DE3713783A1 (de) * 1986-04-25 1987-10-29 Murata Machinery Ltd Verfahren zum ermitteln einer fehlerstelle in einem faden
US4880175A (en) * 1987-04-14 1989-11-14 Murata Kikai Kabushiki Kaisha Tension setting and controlling method and apparatus in an automatic winder
DE10118660A1 (de) * 2001-04-14 2002-10-17 Schlafhorst & Co W Garnreinigungseinrichtung an der Spulstelle einer Textilmaschine

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5086542A (en) * 1990-11-30 1992-02-11 Franklin James R Electronic stop motion for textile draw frame
DE102005017606A1 (de) * 2005-04-16 2006-10-19 Saurer Gmbh & Co. Kg Verfahren und Vorrichtung zur Qualitätsüberwachung eines laufenden Fadens
CN103060972A (zh) * 2013-01-17 2013-04-24 杭州电子科技大学 一种基于中值滤波的电子清纱器纱疵快速识别方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2506174A (en) * 1946-05-10 1950-05-02 Clark Thread Co Electronic thread clearer
US2936511A (en) * 1954-08-06 1960-05-17 William Hollins & Company Ltd Yarn clearing apparatus
US3053986A (en) * 1959-12-31 1962-09-11 Loepfe Erich Thread cleaner for textile machines
US3106762A (en) * 1959-08-14 1963-10-15 Riera Juan Solanich Electronic apparatus for detecting and eliminating iregularities in threads
US3258824A (en) * 1963-09-28 1966-07-05 Reiners Walter Apparatus for checking of travelling yarn in textile machinery
US3309754A (en) * 1960-09-23 1967-03-21 Metcalf Eric Self-regulating light-responsive devices

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1384229A (fr) * 1963-12-20 1965-01-04 Loepfe Ag Geb Procédé et dispositif de contrôle du fil dans un bobinoir de fil textile

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2506174A (en) * 1946-05-10 1950-05-02 Clark Thread Co Electronic thread clearer
US2936511A (en) * 1954-08-06 1960-05-17 William Hollins & Company Ltd Yarn clearing apparatus
US3106762A (en) * 1959-08-14 1963-10-15 Riera Juan Solanich Electronic apparatus for detecting and eliminating iregularities in threads
US3053986A (en) * 1959-12-31 1962-09-11 Loepfe Erich Thread cleaner for textile machines
US3309754A (en) * 1960-09-23 1967-03-21 Metcalf Eric Self-regulating light-responsive devices
US3258824A (en) * 1963-09-28 1966-07-05 Reiners Walter Apparatus for checking of travelling yarn in textile machinery

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3631354A (en) * 1969-03-05 1971-12-28 Schweiter Ag Maschf Apparatus for the automatic adjustment of a yarn cleaner
US3673591A (en) * 1969-11-06 1972-06-27 Peyer Siegfried Yarn defect detector apparatus for textile machinery
US3643882A (en) * 1970-03-09 1972-02-22 Lessona Corp Yarn handling
US3734422A (en) * 1970-05-28 1973-05-22 Loepfe Ag Geb Apparatus for monitoring yarn at winders
US3774860A (en) * 1970-05-28 1973-11-27 Laepfe Ag Geb Apparatus for evaluating the winding speed of cross-winders
US3844498A (en) * 1970-05-28 1974-10-29 Loepfe Ag Geb Apparatus for evaluating the winding speed of cross-winders
US3758216A (en) * 1971-05-27 1973-09-11 Loepfe Ag Geb Electronic appliance for setting and checking electronic yarn clearers
US3860185A (en) * 1973-12-28 1975-01-14 Nippon Selen Co Ltd Rotation detector in a fixed length yarn winding apparatus
US4036445A (en) * 1974-05-15 1977-07-19 Aktiengesellschaft Gebruder Loepfe Circuit arrangement for monitoring the operation of an electronic yarn clearer
US4292868A (en) * 1979-03-08 1981-10-06 Maschinenfabrik Schweiter Ag Textile spooling machine, an apparatus and method to prevent the formation of loose cut thread pieces
US4512526A (en) * 1981-04-13 1985-04-23 Murata Kikai Kabushiki Kaisa Doffing control system in automatic winder
DE3611263A1 (de) * 1985-04-05 1986-10-16 Murata Kikai K.K., Kyoto Verfahren zum steuern einer spulstelle und spulautomat mit einer steuerschaltung
DE3713783A1 (de) * 1986-04-25 1987-10-29 Murata Machinery Ltd Verfahren zum ermitteln einer fehlerstelle in einem faden
US4817425A (en) * 1986-04-25 1989-04-04 Murata Kikai Kabushiki Kaisha Yarn defect detecting method
US4880175A (en) * 1987-04-14 1989-11-14 Murata Kikai Kabushiki Kaisha Tension setting and controlling method and apparatus in an automatic winder
DE10118660A1 (de) * 2001-04-14 2002-10-17 Schlafhorst & Co W Garnreinigungseinrichtung an der Spulstelle einer Textilmaschine

Also Published As

Publication number Publication date
GB1093315A (en) 1967-11-29
BE681707A (de) 1966-10-31
DE1560640B1 (de) 1970-10-08
CH422603A (de) 1966-10-15
NL6604683A (de) 1967-01-09
SE313199B (de) 1969-08-04
AT276170B (de) 1969-11-10

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