EP0417623A1 - Edge control system - Google Patents

Abstract

A device for recognizing and adjusting deviations in the cylindrical yarn deposit on the inside of the flange (23, 23 ') of warp beams or part warp beams (24) in warping machines has two sensor heads (4,4') with three sensors (1,2,3; 1 ', 2', 3 ') on each flange (22, 22') and the corresponding switching and control devices.

Description

The invention relates to a device for recognizing and adjusting deviations in the cylindrical yarn deposit on the flange sides of warp beams or partial warp beams in warping machines, in which a reed which is adjustable in width determines both the width of the thread sheet and its position relative to the flange sides.

DE-OS 34 04 255 discloses a device for checking and adjusting the winding structure formed by a group of threads running side by side on a warp beam with side flanges for warping or warping machines. The width of the thread coulter as well as its relative position to the warp beam is determined by means of a warp. Measured value transmitters are arranged at the two ends of the winding and, depending on the respective angular diameter, emit a measured value influenced by the angular diameter. In addition, at least one setpoint transmitter which is influenced in the same way by the winding diameter is provided, which is arranged inward alongside the measured value transmitters and generates a setpoint which, together with the measured values provided by the measured value transmitters, in each case produces a differential value in the event of a deviation of setpoint and measured value is compared. The two difference values generated in this way are then linked to one another in such a way that in the case of the same Difference values the warping unit changes the width of the thread group and / or in the case of different difference values the warping unit shifts the thread group.

A disadvantage of the known device is that it does not take into account a change in the position of the flange sides as the winding diameter increases, which is caused by the fact that the family of threads pushes the flange sides more and more outwards during winding. In the current partial warp beams (TKB), the flange sides are pressed outwards by several mm towards the end of the winding process. As a result, when the thread sheet is wound onto the cylindrical thread carrier (TKB), the edges of the flanges are repeatedly poor. One speaks of a bad edge build-up when the cylindrical yarn development does not continue clearly up to the flange, but the yarn runs off or runs on the flange. In operation, the warping shifts, which leads the threads before they run onto the tree in order to avoid a mirror formation of the wound thread coulter. With this reed, the width of the thread sheet is adjusted by more or less strong transverse position as well as the right and left limit to the TKB. If this limitation or the inclination or width of the reed is not set correctly or if changes occur during the winding process, then the bad edge build-up mentioned occurs. A change occurs, among other things, when the amount of yarn wound increases the pressure on the flanges and pushes them outwards.

The object of the invention is to provide a device for detecting and readjusting deviations of the cylindrical yarn deposit on the flange sides of warp beams or partial warp beams, taking into account the flange deflection.

To solve this problem, the device of the type mentioned, which is characterized by a sensor head on each flange, which is at the free end of a bracket is mounted and carries a first sensor, a second sensor and a third sensor, which are connected via electrical lines to a programmable logic controller, the second and third sensors being aligned with one another in such a way that they output their signals at an angle of 90 ° and received while the first sensor is positioned and aligned therebetween at an angle of 45 °; by a cross table that moves the bracket in two mutually perpendicular directions under the action of two stepper motors controlled by the controller; and by two Riet motors, which are also controlled by the control system and one of which moves the Riet parallel to the axis of the partial warp beam, while the other adjusts its width.

The result of this is that the sensor head always maintains the same distance from both the flange side of the tree and the outside diameter of the winding and can thus recognize and readjust the width and orientation of the thread sheet at the desired point.

The first and second sensors are preferably infrared sensors, while the third sensor is an inductive sensor.

The first IR sensor expediently has its focal point at about 2 mm in front of the flange on the yarn, so that it can detect a deviation from the ideal end winding, positive or negative, of approximately 0.1 mm.

The second IR sensor has a larger measuring field and expediently maintains a constant distance of approximately 8 mm from the yarn.

The third sensor, as an inductive sensor, holds the sensor head at a constant distance from the flange of the partial warp beam and thus the first IR sensor exactly in its position. By processing the signals from the first sensor, the reed can be used to guide the Thread coulter can be controlled.

• Figur 1 eine schematische Darstellung des Auführungsbeispiels;
• Figur 2 Wicklungsfehler auf Teilkettbäumen.

The invention is explained in more detail below with reference to figures; show it:

• Figure 1 is a schematic illustration of the performance example;
• Figure 2 winding errors on partial warp beams.

FIG. 1 shows a schematic representation of a group of threads 5 which is wound onto a partial warp beam 24 by a warping gate, not shown, via a reed 10 which is adjustable in width, a so-called expansion reed. For this purpose, the reed 10 has a number of joints 9 which can be moved back and forth in a guide 25 in a manner to be explained later. In this way, the individual reed legs 10 'can be pulled apart to a greater or lesser extent, thereby changing the width of the sheet 5.

It is pointed out that instead of an expansion reed, another type of reed, for example a swivel reed, can also be used. A swivel reed is not pulled apart, but swiveled around a pivot point to change the width of the thread sheet.

A first Riet motor 20, which is controlled by a controller 8 and receives its control commands via a line 30, serves to adjust the width of the thread family 5. The first Riet motor 20 drives a screw spindle 40, which has a collar 41 in the center, which is mounted in bearings 42 against lateral displacement, via an indicated gear ratio. Such a Riet construction is generally known to the person skilled in the art. The screw 40 carries in the region of its ends a nut 43,43 ', on which two of the joints 9 are arranged. If the first Riet motor 20 sets the screw 40 in rotation, then the nuts 43 and 43 'are moved in the axial direction of the screw 40 and thereby pull the joints 9 apart in a first direction of rotation while being pushed together in a second direction of rotation.

A second reed motor 21 is used to move the reed 10 parallel to the axis of the partial warp beam 24, whereby the family of threads 5 can be moved laterally with respect to the flanges 22, 22 '. The control of the second Riet motor 21 is also carried out by the controller 8 by supplying suitable control commands on a line 31.

The core of the invention, namely the sensor head 4, is described below. In the drawing, a sensor head of essentially identical construction is shown for the right and left side of the partial warp beam 24. The individual parts are therefore provided with the same reference numerals; they differ only by an apostrophe. For reasons of clarity, only the left sensor head 4 is described below. It is shown positioned approximately in the middle of FIG. 1 on the inner flange side 23 of the flange 22 of the partial warp beam 24.

The sensor head 4 is attached to the free end of a holder 6 which is mounted on a cross table 14. The person skilled in the art can easily be expected to build a suitable holder, for example by providing a profile with a toothed rack, not shown, which can be moved back and forth on its longitudinal axis by the pinion 19 of a stepping motor 17. It is clear that the rack must be performed in bearings, not shown, for this purpose. In this way, the sensor head 4 can be moved by the stepping motor 17 in a first or X direction, which expediently runs radially to the partial warp beam 24. A further direction of movement of the sensor head 4, namely in the Y direction, makes it possible to move the sensor head 4 parallel to the axis of the partial warp beam 24. This is possible with the help of the cross table 14 in a manner known per se, for example in that the holder 6 on a bed 7 arranged at right angles thereto is perpendicular to its length stretching can be moved. For this purpose, for example, another stepper motor 16 is used, the pinion 15 of which meshes with a rack, also not shown, mounted on the bed 7. The two stepper motors 16 and 17 are controlled by the controller 8 via lines 36 and 37.

Figure 1 also shows details of the sensor head 4, which carries three sensors 1, 2 and 3. The first and second sensors 1 and 2 are infrared sensors, while the third sensor 3 is an inductive sensor. The second sensor 2 and the third sensor 3 are mounted so that their radiation axes enclose an angle of 90 °. In between, the first sensor 1 is attached under the radiation direction of 45 °. The first IR sensor 1 is aligned with the point of the ideal end winding of the partial warp beam 24. In operation, its sensor focus is around 2 mm in front of the flange on the yarn.

The second IR sensor 2 emits infrared radiation in the radial direction onto the wound yarn, which is reflected and picked up again in the radial direction. It should serve to maintain a constant distance of, for example, about 8 mm from the yarn.

The third sensor 3 is an inductive sensor which is directed towards the inside of the flange 23 and is intended to keep the sensor head 4 at a constant distance from the flange 22. The signals from the three sensors 1 - 3 are fed via lines 11, 12 and 13 to the controller 8, which is a programmable logic controller, after processing by analog amplifiers 26, 28 and threshold switches 27, 29.

• Die Fehler 1-4 werden durch Breitenänderung und Verschieben des Riets 10 korrigiert.
• Die Fehler 5 und 6 werden nur durch Breitenänderung des Riets 10 korrigiert.
• Die Fehler 7 und 8 werden durch Verschieben des Riets 10 korrigiert.

FIG. 2 shows eight defective windings of a partial warp beam, which are compensated for by the three sensors 1 - 3 via the programmable logic controller 8 (PLC) using the stepper motors 16 and 17 and the Riet motors 20 and 21.

• The errors 1-4 are corrected by changing the width and moving the reed 10.
• Errors 5 and 6 are only corrected by changing the width of reed 10.
• Errors 7 and 8 are corrected by moving reed 10.

Functional description Sensor 1.1 ′

The sensors 2.2 'and 3.3' hold the first sensor 1.1 'exactly in their position. For example, if it detects a positive deflection of the winding (leading edge), this causes a positive change in the 0 - 20 mA output of its sensor amplifier. This current is fed to a first analog amplifier 26. The working range of the first analog amplifier 26 is 0-100% and the limits can be varied as desired. Its output voltage is accordingly 0-10 volts DC. This voltage is converted into a defined switching point in a downstream first threshold switch 27 and sets a relay (not shown). The relay addresses an input in the programmable logic controller (PLC) 8. Likewise, the signals from the other sensors 2 and 3 and the sensors 1 ', 2' and 3 'of the other side of the tree are received. Corresponding different links activate one or more PLC outputs for a certain time. They act on the two reed motors 20 and 21. The first reed motor 20 moves the reed 10 to the right or left, while the other reed motor 21 adjusts the width of the reed 10, thereby changing the width of the thread sheet 5 becomes. The sensors 2 and 3 act on the stepper motors 16 and 17, the sensors 2 'and 3' on the stepper motors 16 'and 17' and thus position the sensors 1 and 1 '.

Sensor 2.2 ′

The sensors 2,2 'have the task of keeping the sensors 1,1' exactly the same distance (e.g. 8 mm) from the wound yarn. In principle, they work like sensors 1, 1 'and, when a decreasing distance is detected, switch via their sensor amplifier, a second analog amplifier 28, a second threshold switch 29 of the PLC 8 and a control unit 18, a first stepper motor 17, 17'. . This moves the holder 6 on which the sensor head 4,4 'is mounted away from the yarn until the set value is reached again.

Sensor 3.3 ′

The distance of each sensor head 4.4 'to the flange is detected by the sensor 3.3', an inductive proximity switch. It has the advantage that differently colored yarn carriers (TKB) can be used. If the proximity switch reports that the distance from the flange is too large, this message goes directly to the PLC 8 and, by linking, triggers the other stepper motor 16 to respond, again via the motor control unit 18. This causes the sensor head 4, 4 'brought back to the same distance to the flange 22 by extending the bracket 6.

At the beginning of the warping, namely when inserting a new partial chain tree, it is necessary to move the entire measuring device into the starting position very close to the partial chain tree 24. Likewise, when the warping process has ended, rapid and trouble-free departure must be ensured. This is achieved by additional measuring elements and processing in the PLC 8 in a manner known per se to the person skilled in the art.

The analog and threshold switches can be omitted if the PLC offers the option of processing the sensor signals like these two.

Claims (5)

1.Device for recognizing and adjusting deviations in the cylindrical yarn deposit on the flange sides (23) of warp beams or partial warp beams (24) in warping machines, in which a reed (10) which is adjustable in width has both the width of the thread sheet (5) and whose relative position determined with the flange sides (23), characterized
by at least one sensor head (4,4 '), which is mounted on the free end of a holder (6,6') and a first sensor (1,1 '), a second sensor (2,2') and a third sensor ( 3.3 ') carries, which are connected via electrical lines (11, 12, 13; 11', 12 ', 13') to a programmable logic controller (8),
wherein the second and third sensors (2,3; 2 ', 3') are aligned with each other such that they output and receive their signals at an angle of 90 °, while the first sensor (1,1 ') in between at an angle is arranged and aligned at 45 °;
by means of a cross table (14, 14 '), which moves the brackets (6, 6') under the action of two stepper motors (16, 17; 16 ', 17') controlled by the controller (8} in two mutually perpendicular directions ( X, Y) moves;
and by two reed motors (20, 21), which are also controlled by the control (8) and one (20) of which moves the reed (10) parallel to the axis of the partial warp beam (24) while the other (21 ) changed in width. 2. Device according to claim 1, characterized in that the first and second sensors (1,2; 1 ', 2') are infrared sensors, while the third sensor (3,3 ') is an inductive sensor. 3. Device according to claim 1 and 2, characterized in that two warp beams (4,4 ') with associated control are provided per warp beam or partial warp beam (24). 4. The device according to claim 1, characterized in that the reed (10) is an expansion reed. 5. The device according to claim 1, characterized in that the reed is a swivel reed which is pivoted about a pivot point by the first stepping motor (20) to change the width of the thread sheet (5).

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