DE2934024A1 - YARN FEEDING DEVICE BETWEEN A YARN STOCK AND A YARN CONSUMER UNIT - Google Patents

Description

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Henkel, Kern, Feiler & Hänzel patent attorneys

I Registered Representatives

. u. before the

European Patent Office

Möhtetraße 37 D-6000 Munich 80

Tel .: 089f982085 «7 Telex: 0529802 hrtkl d Telegrams: ellipsoid

U-734

22 Aug 1979

Yarn feed device between a yarn supply and a yarn consumer unit

The invention relates to a yarn feed device between a yarn supply and a yarn consumer unit, in particular a device for feeding yarn under controlled conditions from a supply to a consumer unit, such as a shuttleless loom, and especially a thread tension and feed speed regulating device, an intermediate station or coupling point (interface) between a thread or Represents yarn supply and a consumer unit using the yarn.

In the classic shuttle loom, the weft yarn is introduced into the loom shed by the shuttle worn weft spool is filled (wound on) itself. The unwinding takes place simultaneously with the passage of the weft bobbin through the shed so that no special (thread) "" tension problems occur.

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Schüfczenlose looms, on the other hand, contain novel and quite a dramatic change in the weft insertion system. Since, for example, the supply of weft threads is stationary and is arranged outside the loom, they occur when it is withdrawn alternating accelerations and decelerations of the yarn from the supply with each stroke or weft of the loom in the thread. The acceleration speed or magnitude is of course directly related to the pulling process of the loom. When accelerating and decelerating, the "Uber-End" withdrawal of the The balloon produced by the supply package is alternately enlarged and reduced. As a result, in the absence of from interposed thread storage means in the acceleration phase of each shot or shot high tensile stresses generated in the weft thread withdrawn from the stationary supply. These high tensile stresses can lead to lead to loop formation or sloughing of the weft thread withdrawn from the supply. aside from that interruptions of the loom operation and loops or kinks in the fabric can occur, which in In each case, the production output of the loom and the quality of the fabric are reduced.

Due to the need for the reliable high speed yarn supply of yarn supplies too shuttleless looms and the like that work intermittently and during the above-mentioned weft or. The beating movement consumes pieces of the length of yarn, so drum storage and tensioning devices are used used to reduce thread loops and thread breaks and the intermittent Removal of the yarn from the supply by the weft insertion system caused thread tensions to even out. An example of such a drum storage device

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processing can be found in US Pat. No. 3,776,480, to which reference is hereby made with regard to such drums and their mode of operation is taken. These previous drums are intended to provide a yarn feed that takes place under constant thread tension of the unit consuming the yarn.

It is also known to measure or tap the storage of the yarn thread on the intermediate drum and the To regulate the drum speed so that the drum is braked as soon as the yarn storage supply is too large. These The technique is described, for example, in U.S. Patent 3,225,446, according to which a multiple differential ratio to acceleration and decelerating the rotation of the drum in response to a decrease or increase in the amount stored on the drum Yarn supply is switched. Another example of such a speed or speed control is found in US Pat. No. 3,796,385, which discloses a pivoting mechanical yarn supply sensor and a corresponding one electrical contact switch for changing the drum speed by turning an AC motor driver circuit on and off.

The previous Tronunel storage system stars for regulating or controlling the thread tension to the consumer unit are either designed so that they work with stepless speed change drum drive motors with introduction the repetitive acceleration / deceleration phases, or so that the engine speed inevitably (inherently) is varied depending on the changing drum load, whereby the drum is to be driven with constant torque. In any case, a yarn loop formation or a knocking off due to the development of the balloon and / or a thread breakage due to the repeated accelerations favored. The drum load and thus the

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Drum speed can vary considerably. There were speed fluctuations of up to 70% due to the change in friction between cold start and Measured operation under stable temperature conditions. In the winding or thread tensions were also Fluctuations measured according to a multiple of 100 g. With AC motors, the slip speed varies with the burden. The speed of DC motors is sensitive to both voltage as well as strain.

The previous designs, especially the drum drives working with constant torque, threw heretofore unsolved problems regarding a wide range of operating conditions when unwinding a Thread from a supply spool onto the drum. In particular, prevent the load changes, conditionally due to yarn winding tensile stresses and frictional forces acting in the storage feeder, an operation at a speed adapted to the loom draw-off speed. Trying to solve this problem too handle, has been usually worked with storage drum speeds that are significantly above the Weft pull-off speed to the consumer unit lie. As a result of this operation, the yarn coming in from the supply package is at an intermittent stop and tarnishing, which promotes the formation of loops or knocking off and thread breaks.

The object of the invention is thus in particular to eliminate the difficulties encountered in the prior art by largely reducing any possibility of loop formation or chipping and thread breakage as a result of fluctuating speed or load on the drum drive motor, especially by regulating the drum

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speed to a constant size, which is practically adapted to the required yarn take-off speed.

This object is achieved by the features characterized in the attached patent claims.

To ensure this constant drum drive the invention provides in particular a speed-controlled DC motor drive for the intermediate (storage) drum a thread tensioning system. A constant drum drive is achieved through feedback control, at which the actual drive speed is kept at a fixed value. One to the yarn consumption rate nominal or adapted to the consumer unit that removes the yarn thread temporarily stored on the drum Target speed is entered into the device in advance.

The invention is therefore based on the previous drum drive control with variable speed to control the yarn supply on the drum and on a regulation for Keeping the drive torque on the drum constant. Keeping the drum speed constant with fluctuating Loading, as it inevitably occurs in such systems, thus results in one with variable Torque, working drum drive, causing thread breaks and loops when feeding or feeding of the yarn from the supply bobbin to the intermediate storage drum can be largely reduced.

In the following a preferred embodiment of the invention is explained in more detail with reference to the accompanying drawing. Show it:

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1 shows a schematic representation with a block diagram an arrangement for driving a drum at constant speed, and

2 shows a circuit diagram of a control device according to a preferred embodiment of the invention.

According to Fig. 1 consumes a shuttleless loom 10 each pieces or sections of a yarn thread Y, which from Loom in the usual way from a supply lap 12 with practically constant thread tension by means of a intermediate, rotating intermediate or storage drum and tensioning unit 14 is withdrawn. The unit 14 can essentially be constructed in a manner known per se (e.g. according to ÜS-PS 3 776 480) and a drum 16 have, on which a tapering to the loom 10 Yarn thread Y is wound up from the twine package 12. The drum 16 of the unit 14 is an example of one Device for pulling off the yarn thread Y from the supply package 12 and for feeding it to the loom 10 below constant voltage.

The unit 14 has a main shaft 20 which is driven with an electric direct current motor 22 connected variable speed and is effectively designed as an armature of the motor 22. The shaft 20 is with a Milling 26 to accommodate a crank-shaped thread guide) tube 30 (Fig. 1) provided. The centerless (centerless) tube 30 is used to guide the yarn thread, see above that this is passed from the supply roll 12 through the tube 30, at the end of which 32 emerges and opens the drum 16 is wound up when the shaft 20 and tube 30 are rotated by the motor 22. When being wound onto the drum 16, the yarn is described in more detail by one of the above-mentioned US Pat

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Yarn feed mechanism from a first end 38 of the Drum 16 is guided to its second or opposite end 40. The yarn is withdrawn from the end of the drum 40 via the end (overend) of the drum 16 and a tapered or conical end piece 48 on the shaft 20, the yarn passing under a stationary brush 50 resting against the surface of the end piece 48. The brush 50 cooperates with the control device to pull the yarn through the loom 10 from the drum 16 to be deducted. From the end piece 48, the yarn runs through a thread guide 54, which is from one to one Support frame 60 for drum 16 and associated parts-mounted bracket 56 is carried to the loom 10. When the yarn Y is wound up and drawn off, the drum 16 is held stationary by several magnets 64, the drum 16 being supported by the shaft 20 via ball bearings 66 and 68 at the two ends of the shaft 20 becomes that it is independent of the rotation of the shaft 20. More details of the above Unit 14 result from the above-mentioned US-PS.

In addition to the mentioned direct current motor 22 for the drum 16, other drive systems, such as gear drives or a belt drive, may be provided to drive the drum as a function of the operating speed of the Drive motor 22 at a suitable speed.

A control unit with a silicon-controlled rectifier or SCR phase-locked loop 70 is generated by a +20 V DC voltage terminal 72 a varying DC voltage on a motor line 74 for regulating the motor speed according to the different occurring Loading conditions, for example for

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Consideration of the mentioned intermittent tensile stress load of the feed yarn Y when it is pulled off the supply package 12 or the friction in the mechanism when starting up when cold; as a result, under all operating conditions over long periods of operation an adjustment of the withdrawal speed of the thread thread from the supply lap 12 to the yarn consumption in the loom 10 guaranteed.

For precise adaptation or setting of the nominal or target speed of the motor and thus the desired speed, with which yarn is to be fed from the supply reel 12 onto the drum 16, to the average The speed at which the yarn is drawn off by the loom 10 is selectively adjustable by hand Speed voltage regulator 78 is provided. This becomes an operating speed setting for the drum 16 achieved, this speed or drum speed then through a feedback circuit from a motor speed detector 80 and a speed-dependent Converter circuit 82 is kept constant at all times. To further reduce changes in load In the mechanism, the detector 80 is preferably a non-contact, magnetic Hall effect detector, which the passing poles of a set of six revolving magnets 84 on one driven by motor 22 Disc 86 scans. The frequency / voltage converter circuit 82 thus measures a frequency proportional to the speed of the motor 22 for converting the same into a frequency corresponding control voltage. This correcting control voltage is generated by the phase-locked loop 70 a feedback variable set, which strives to keep the speed of the DC motor constant on the the control device 78 set speed to hold.

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when deviations in load, voltage or other system variables occur.

This operation of the drum 16 at a constant speed avoids the frequent acceleration and deceleration phases which cause loops or knocking off and yarn breaks in the yarn yarn Y guided from the supply package 12 onto the drum 16 are caused.

For the correct operation of the intermediate storage drum 16, the amount of yarn located on this is determined by a pivotable iron element 90. This measurement is made as in the case of measuring the engine speed, without any additional friction or load introduced by one magnetic hall effect detector 92; as soon as the supply of yarn on the drum 16 becomes too large, it pivots element 90 moves away from detector 92 and vice versa. Here, an ON / OFF control circuit 94 is used for the DC motor 22 operated to overfill the drum 16 with yarn for certain reasons, for example in To prevent the loom 10 from coming to a standstill.

During operation, the voltage regulating device 78 is therefore set in such a way that the rotational speed or peripheral speed of the drum 16 is very close to the speed required to adjust the yarn withdrawal from the drum is required by the loom, but exceeds this speed very slightly. The ON / OFF control circuit therefore only needs to work occasionally in order to routinely compensate for a yarn oversupply, so that the acceleration / deceleration phases caused by switching off and restarting the motor reduced to a minimum and thus the corresponding thread tension and balloon formation problems can be avoided when pulling the balloon 98 from the supply roll 12 onto the drum 16.

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Obviously, with. Exception to this rare one Fluctuations, the Troeael 16 always with constant Speed driven so that the yarn Y continuously from the Supply roll 12 onto drum 16 at one speed is supplied, which is adapted to the average withdrawal speed on the loom 10. Consequently no change occurs during normal operation of the system the drum speed or speed.

The electrical control or regulating circuit is illustrated in Fig. In which the parts previously described are denoted by the same reference numerals as before.

The magnetic motor speed detector 80 in the form of a Hall effect device engages with each revolution of the Disk 86 of Fig. 1 from the six magnetic poles and provides a corresponding pulse repetition frequency to an input circuit 64 for processing in the frequency / voltage converter 82. The circuit operating voltage of +12 V (DC voltage) at a terminal 100 and the motor supply voltage of +20 V (DC voltage) at the terminal 72 are supplied from a suitable DC power supply, not shown. The individual circuit parameters can be seen, and the various in Elements shown in block form are commercially available components to be described in more detail.

The resulting variable output voltage which the is proportional to the actual drum speed, appears on a line 104 as a control input to the Terminal 106 of the speed control circuit 70 with a variable by which the speed of the motor 22 is set is used to compensate for changes in load, voltage, etc. during operation, by controlling a

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a silicon controlled rectifier device 110, the with the motor 22 in the voltage supply line from terminal 72 is connected in series.

The engine speed signal provided by the detector 80 is fed to the frequency / voltage converter 82, which the Output pulses of the detector 80 in a DC voltage converts. The size of this DC voltage is set by the voltage control unit 78, which the nominal speed of the motor 22 is determined and therefore set so that the speed or peripheral speed of the Drum 16 is matched to the mean withdrawal speed of the yarn in the consumer device.

The magnetic Hall effect detector 92 for determination of the yarn supply on the drum 16 controls the transistorized electronic switch circuit 110, which by means of a transistor 112 selectively sets a voltage practically at ground level on the line 105, thereby preventing motor current from flowing through the device and turning off the motor. In preferred Embodiment, the motor is completely switched off, so that the circuitry the drum in the event of a yarn feed failure Can bring etc. to a standstill and also monitors the capacity of the drum 16 and a overcrowding the same prevented. The drum only needs to be overfilled to switch the drum on and off to be determined in order to perform the supply monitoring function when the speed controller 78 is set to a drum speed which is slightly greater than that for feeding the Consumer unit required speed. In this mode of operation is the number of engine speed changes compared to the previous device in which the drum speed has to be changed repeatedly

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and therefore an increased likelihood of thread balloon formation or knocking off and thread breaks results, reduced to a minimum.

The preferred embodiment also ensures effective Controls or regulations that in no way load the drum or the yarn guide paths and thus the sensitive Would disturb the balance, which is essential for trouble-free high-speed yarn processing over a long period of time Is necessary across operating periods. This is due to the electronic-magnetic sensor arrangement used guaranteed, which also has a long service life and no mechanical or electrical wear Is subject to contact problem. The measuring frequency parameters determined by the RC networks used are also suitable and the time constants of the electronic circuit (s) ideally for quick response to the intermittent, instantaneous stress conditions or states due to withdrawal of the yarn from a bobbin or due to system friction, etci; this quick response can be achieved mechanically actuated sensor elements or mechanically moved Controls are not guaranteed.

Although the circuit technology, apart from the special system, is conventional per se and also different can be carried out, the embodiment shown can be made from the following commercially available components be constructed:

Motor 22 Model 12FP from Printed

Motor Division, Kollmorgen Corporation, Glen Gove, N.Y./USA

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Hall Effect Detector Model UGN-3020T from 80 and 92 Sprague Electric Company, Con

cord, New Hampshire / USA

Frequency / voltage part no. RC4151NB from the company

^{Integrated Circuit} Raytheon, Semi-Conductor Division, Mountain View, CaI./USA

SCR engine speed model no. L120B1, SGS - Ates, “? ι freeze «» Ί ^ Semiconductor Corporation

Newtonville, Mass./USA

Thus, as will be apparent from the foregoing description, the invention provides an improved apparatus for regulating the thread tension and the conditions when feeding a thread from a supply bobbin to a consumer unit, such as a loom, in which the speed of rotation is used as a buffer and tensioning device serving drum constant at the average yarn take-off speed of the loom is adjusted. According to the invention, a reliable yarn feed or is long-term -feed guaranteed, while problems with loops or knocking off and thread breakage over a wide range of thread sizes and feed speeds can be largely eliminated.

Summary: The invention relates to a device for adjusting the yarn withdrawal speed of one Yarn supply lap to that of a consumer unit, such as a shuttleless loom to reduce the Probability of thread loops or chipping on the supply lap and thread breaks due to of conditions such as large changes in load on a rotatable drum for intermediate yarn storage and thread tension. This drum is through a

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Claims (8)

Henkel, Kern, Feiler & Hänzel Patentanwälte Registered Representatives before the European Patent Office Möhlstrasse 37 D-8000 Munich 80 Tel .: 089 / 982085-87 “. . Telex: 0529802 hnkl d Leesona Corporation Telegrams: ellipsoid Warwick. R.I., V.St.A. U-734 Aug 22, 1979 claims 1. Yarn feed device between a yarn supply and a yarn consumer unit, such as a textile machine, which a yarn thread with practically constant Speed is to be fed, characterized by a drum feed device to remove the thread from the supply and to wind the thread around the drum for the purpose of later continuation to the consumer unit, by a variable speed DC motor for driving the feed device to the Yarn thread from the supply at a speed determined by the speed of the feed device (drum) deducted by a speed control unit for setting a constant speed of the DC motor depending on feedback input data, through a connected to the speed control unit, selectively adjustable tension setting device for setting a thread feed speed 19/0615 speed substantially corresponding to the predetermined average value, and by a feedback detector unit, which supplies a signal proportional to the speed of the motor and which is connected in such a way that the motor speed under changing load conditions by changing the motor voltage and torque at the predetermined size, maintaining continuous rotation of the feeder and the thread of the consumer unit over comparatively long periods of time with the average Yarn feed or feed speed is supplied, so that acceleration and deceleration phases the drum feeder and thus the formation of loops or knocking off and thread breaks largely avoided in the yarn thread. 2. Apparatus according to claim 1, characterized in that an overload measuring device Provides input data to the speed control unit to prevent the speed of the feed device only dor accumulation of excess yarn on the drum to reduce. 3. Apparatus according to claim 1, characterized in that the speed control unit the dem DC voltage supplied to the motor regulates. 4. Device according to A 3, characterized thereby h- n e t that the feedback unit can be fed with a variable voltage as a function of speed changes is to change the DC voltage to the motor. 5. Apparatus according to claim 4, characterized in that a contactless magnetic coupling the supplies variable feedback voltage as a function of speed changes. 030019/0615 6. Procedure for adjusting the speed of the yarn feed between a yarn supply and a yarn consumer unit, which decreases the yarn thread at a practically constant mean speed, thereby g e k e η η ~ ζ e i chnet that a storage device to pull off of the yarn thread is actuated by the yarn supply that the storage device with a substantially constant Yarn withdrawal speed is controlled to pull the yarn thread with a practically constant mean Withdrawal speed of the yarn consumer unit adapted speed to the storage device and that the withdrawal speed of the storage device by a feedback control device as a function of the actual memory extraction speed is kept constant. 7. The method according to claim 6, characterized in that the storage device in its Actuation with practically constant pulling speed by means of a direct current motor with adjustable speed is driven and that the voltage supplied to the motor for setting the constant peeling speed is regulated. 8. The method according to claim 6, characterized in that that the drive torque transmitted to the storage device as a function of intermittent load changes on the storage device will be changed. Ü30019 / 0615