EP0774537A1 - Warping machine - Google Patents

Abstract

A process is for sectional warping of yarns on a sectional warping drum of a sectional warper. In a start phase, a theoretically correct feed speed is set as an initial value for at least the first rotation of the sectional warping drum. The determining takes place in accordance with warp parameters. In a subsequent phase, the application thickness of the first sectional warping band is measured. The feed speed is regulated from the second rotation of the drum at the earliest. In a work phase, a constant feed speed is set for the rest of the process after the stabilisation of the regulated feed speed signal.

Description

The invention relates to a method for warping threads according to the preamble of claim 1 and a warping machine according to the preamble of claim 7.

A method for warping threads on a warping drum of a warping machine is known from DE-OS 37 02 293. In this method, a warping mechanism is shifted relative to the warping drum as a function of the increasing winding thickness by scanning the winding circumference from a sensing element when the warping drum is at a standstill while the first band is being warmed with a predetermined warping carriage feed, and thereby adjusting its path during a measuring winding phase as a function of the number of revolutions the warping drum is measured. Then, when the remainder of the first warping belt is warmed and after the measuring roll has been copied when the subsequent belts are warmed, the advance of the warping carriage when the rest of the subsequent belts are warmed is corrected in accordance with the measured adjustment path. First, when the first band is warped, a base winding with a predetermined warping carriage feed warmed and its winding circumference scanned by the feeler, the adjustment of which is measured depending on the number of revolutions. The feeler element is then adjusted in accordance with the adjustment path measured when the base winding is warmed and a corrected feed provided for the rest of the first band is determined from the difference between the measured adjustment path in the measurement winding and the measured adjustment path in the base winding. All other warping belts are warmed like the first band with regard to the base and measuring roll with the specified feed and the remaining roll with the corrected warping carriage feed.

The disadvantage of the known method is that a stepped winding is created due to the three-part structure of the first warping belt. Another disadvantage is that although the corrected feed value is already known, the subsequent windings must be wound in the same way, i.e. also with the base and measuring windings with the originally specified warping carriage feed, in order to ensure that all subsequent warping belts have the same structure.

From DE 40 07 620 C2 it is known to determine the application thickness with the aid of a laser light distance measuring device which is directed onto a pressure plate pressed against the winding structure.

The invention has for its object to provide a method for warping threads on a warping drum, in which a step winding structure is avoided and in which subsequent warp belts can be wound with the corrected warping feed once determined.

According to the invention, the features of claims 1 and 7 serve to achieve this object.

The invention advantageously provides that the warping can take place fully automatically from the beginning and without loss of material. For this purpose, a start and a learning phase are planned at the beginning of the warping process. In the start phase, an initial value for the feed rate depending on the warp parameters, e.g. the total number of threads of the warp width and the thread number. This preliminary, theoretically determined feed speed value is used as the feed speed signal at least for the first rotation of the warping drum. The learning phase begins either with the start phase or after the start phase, with the application thickness of the warping belt being measured continuously without contact in the learning phase by holding an application thickness measuring device at a predetermined, essentially constant distance from the surface of the warping belt being wound up. The essentially constant distance from the surface of the thread sheet is required in order to keep the application thickness measuring device in its optimal measuring distance from the surface of the warping belt, since an extremely precise distance measurement is important. The application thickness can be determined from the signals of the application thickness measuring device and, depending on the application thickness, the feed speed can be regulated at the earliest from the second rotation of the warping drum.

The duration of the learning phase depends on the stabilization of the feed speed signals specified by the control. This stabilization occurs depending on Yarn quality after a different number of turns, e.g. after about 30 turns. If the control has been stabilized to a certain extent, a predetermined number of feed speed signals received last is used to determine a constant feed speed signal valid for the working phase of the warping process. The entire remaining warping process is carried out at this feed rate determined in the learning phase.

It can be provided that the maximum correction of the feed rate signal per measuring cycle of the application thickness measuring device is limited at the beginning of the learning phase. This prevents the control from rocking. The feed rate signal is then corrected in several steps in the same direction, if necessary, so that a strong overshoot of the feed rate signals by the correct feed rate value is avoided.

It is preferably provided that a laser light distance measuring device is used as the coating thickness measuring device. For optimal control, a measuring device with a high resolution of the measured values is required. The contactless distance measurement with the laser enables a resolution of approx. 30 µm.

It can advantageously be provided that the constant feed rate signal in the working phase is set to the mean value of the feed rate signals obtained in a predetermined number of measuring cycles in the learning phase if the maximum feed rate signals in the learning phase also fell below a predetermined maximum fluctuation range becomes. The switchover from the learning phase to the working phase therefore takes place when the standard deviation, for example the last 10 or 20 feed speed signals, falls below a predetermined maximum limit value.

It is envisaged that the constant feed speed signal is fed back to the control at the beginning of the working phase in order to determine the number of turns required to maintain the warp length set on the warping machine and to transmit an exact count signal for the current warping process to the motor control which ensures compliance with the exact Warp length guaranteed. A preset number of turns can be corrected if necessary. At the same time, the control system can issue a warning signal if the capacity is exceeded. If the order size is exceeded, the warping machine can be switched off automatically.

The application thickness measuring device is preferably moved synchronously with the rotary movement of the warping drums and the change in the position of the warping belt. The distance measurement is preferably aimed at the center of the warping belt.

The device according to the invention is characterized in that the application thickness measuring device can be moved both parallel to the warping drum axis and orthogonally to the warping drum axis in synchronism with the warping drum rotation and the change in position of the warping belt, the application thickness measuring device maintaining an essentially constant, predetermined distance from the warping belt surface .

Fig. 1

eine Konusschärmaschine im Aufriß und im Schema,

Fig. 2

den Bandaufbau bei einer Konusschärmaschine,

Fig. 3

eine Ansicht des Supports mit dem an dem Support angebrachten Antriebsmechanismus für die Höhenverstellung desselben, die Querverstellung des Schieberiets und die Verstellung der Auftragsdicken-Meßeinrichtung,

Fig. 4

eine teilweise geschnittene Seitenansicht gemäß Fig. 3, und

Fig. 5

die Steuerung der Schärmaschine.

The application thickness measuring device can advantageously be attached to the carriage carrying the warp and can execute the tracking movement together with the warp. Show it:

Fig. 1

a conical warping machine in elevation and in the diagram,

Fig. 2

the belt construction in a cone warping machine,

Fig. 3

a view of the support with the drive mechanism attached to the support for the height adjustment of the same, the transverse adjustment of the sliding rivet and the adjustment of the application thickness measuring device,

Fig. 4

a partially sectioned side view of FIG. 3, and

Fig. 5

the control of the warping machine.

The cone warping machine 1 has a warping drum 2 with a cylindrical part 3 and a cone part 4. The warping drum 2 is supported in bearings 6 by a base frame 7. The base frame 7 is designed as a carriage and can be moved back and forth on rails 9 by means of the running wheels 8. A motor 11 with a rotary pulse generator drives the shaft 5 and thus the warping drum 2 by means of a transmission element 12 and a belt wheel 13, a brake 14 being provided for a brake disk 15. With 16 the traction motor is designated. Another motor 17 drives a threaded lead screw 18, from which a support 20 can be pushed back and forth along the warping drum 2 by means of a spindle nut 19.

The support 20 has a warping slide 21 which can be pushed back and forth on guides along the warping drum 2 by means of the spindle 18. A further carriage 23 is attached to the warping carriage 21 in a height-adjustable manner. The further carriage 23 carries the drive mechanism for the movement of a sliding rivet 25 transversely to the warping drum 2 and for the height adjustment of the further carriage 23 with the other parts attached to it, as well as an arm 48 which has an application thickness measuring device 55 orthogonal to the drum axis of the warping drum 2 holds approximately in the middle of the warping belt to be wound up.

A motor 28 drives a shaft 31 by means of the transmission members 29, 30, from which a plurality of drives are derived. The sliding rivet 25 is located on a cross slide 32. A transmission member 33 leads from the shaft 31 to a worm drive 34 which drives a threaded spindle 35 which can move the slide 32 in the transverse direction to the longitudinal axis of the drum 2. The sliding rivet 25 is seated on a spindle 37 which is driven by its own motor 38 which is fastened to the carriage 32. The displacement of the reed 25 in the longitudinal direction to the drum 2 is therefore independent of the displacement transverse to the drum axis.

On the shaft 31 there is a gear 40 which meshes with a further gear 41, the shaft 42 of which is connected to a worm drive 43 which drives the spindle 44. The spindle nut 45 is fastened to the support slide 21, so that when the spindle 44 is actuated, the slide 23 is displaced in height.

Fig. 2 shows the winding construction of the first warp a cone part 4 with a cone angle α to the drum axis of 15 °.

berechnet.The order amount per drum revolution is denoted by h, so that the theoretical feed rate s _v per drum revolution arises $${\text{s}}_{\text{v}}\text{= h / tan α}$$

calculated.

The process for warping threads runs automatically in that the entire chain can be wound up without interrupting the winding process from the start of the warping process, the first winding also being wound from the beginning at an optimal feed rate.

In the starting phase, the control computer 64 gives an initial signal for the feed speed s _v to a synchronous control 62, which in turn controls the drives 17 and 28, that is the support motor and the motor for the height adjustment, synchronously with the drum rotation. The initial value is calculated from the warp parameters, for example the total number of threads of the warp width and the thread number, for example by dividing the total number of threads by the warp width and the thread number. The resulting initial value for the feed rate is only required for the first or the first revolutions.

This first preliminary feed value already represents a very good approximation of the final feed value, which is still to be determined, so that the warping practically from the first winding position with the required feed rate.

The learning phase begins at the latest from the second revolution, in which the application thickness of the warping belt is continuously measured contactlessly with the aid of the application thickness measuring device 55, by forwarding a distance signal to a feed computer 60. At the same time, two initiators 66, 68 located at a circumferential distance from one another on the drum circumference detect the rotary movement of the warping drum 2 and its direction of rotation. The initiators also pass on their signals to the feed computer 60 and start it.

From the second drum revolution, the feed computer receives order thickness measurement signals, from which the feed computer 60 can determine corrected feed speeds and can transmit a control signal s _v -Rule to the synchronous control 62, which change the feed speed and the height of the warping 25 with the motors 17 and 28 can. The application thickness measuring device 55 is moved due to the attachment to the carriage 23. The application thickness measuring device 55 is also adjusted in the vertical direction in such a way that an essentially constant distance of approximately 50 mm from the warping belt surface is maintained. In this way, the laser light distance measuring device, which is used as the coating thickness measuring device 55, is always in the optimal measuring range, so that the distance between the measuring head and the warping belt surface and thus the coating thickness can be measured without contact with very high accuracy. The resolution of the laser light distance measuring device is approx. 30 µm. A possible blow of the warping drum 2 can be filtered out and be taken into account when measuring the application thickness.

In the learning phase, new measured values for the thickness of the application are generated every 40 ms. At the beginning of the application thickness measurement, the scope of the correction of the feed speed signals is expediently limited in order to avoid control vibrations. After a certain number of drum revolutions, the regulated feed speed signals stabilize by reducing the fluctuation range of successive signals. After stabilizing the controlled feed rate signals, e.g. After 20 to 30 revolutions of the drum, depending on a limit value for the standard deviation or other limit values, the learning phase can be ended and the mean value of the last feed speed signals can be prescribed as a constant feed speed signal that is binding for the rest of the warping process. This ensures that an optimal feed rate is automatically determined and used uniformly for the entire warping process. In the working phase, all subsequent warping belts are thus warmed with this final feed from the start without having to measure the thickness of the application again. Compared to the first warping belt, there is no different winding structure for the subsequent warping belts, since the final feed has already been set after a few winding layers.

The end value of the feed rate signal determined after the end of the learning phase and at the beginning of the working phase is sent to the control computer 64 by the Feed computer 60 reported back so that the control computer 64 can determine the exact number of turns in order to adhere exactly to the warp length set on the control panel 56 of the control.

Claims (6)

Warping machine with a warping drum (2) and a warping roller (25) which can be moved on a warping carriage (21) parallel to the warping drum (2) and in the vertical direction and via which warping bands can be wound on the warping drum (2), with an application thickness measuring device (55) , and a device for detecting the number of warping drum revolutions and a control (60, 62, 64) which generates a feed signal for the warping reed (25) as a function of an application thickness signal and a revolution count signal,
characterized,
that the application thickness measuring device (55) can be moved both parallel to the warping drum axis and orthogonal to the warping drum axis synchronously with the warping drum rotation and the change in position of the warping belt, and that the application thickness measuring device (55) maintains a substantially constant predetermined distance from the warping belt surface. Warping machine according to claim 1, characterized in that the control (60,62,64) from the current distance signal of the application thickness measuring device (55) generates a correction signal for the feed speed signal, which the application thickness measuring device (55) automatically tracks. Warping machine according to one of claims 1 or 2, characterized in that the application thickness measuring device (55) consists of a laser light distance measuring device. Warping machine according to one of claims 1 to 3, characterized in that the application thickness measuring device (55) is arranged on a height-adjustable, further carriage (23) attached to the warping carriage (21). Warping machine according to one of claims 1 to 4, characterized in that the measurement of the measured value of the application thickness measuring device (55) is automatically set to the optimum measuring cycle time depending on the thread thickness and yarn number. Warping machine according to one of claims 1 to 5, characterized in that the measured value sampling of the application thickness measuring device (55) takes place with a cycle time of approx. 10-100 ms, preferably between 20-60 ms.

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