EP0366048B1 - Method and device for controlling the gripping and releasing of all cores or bobins of an automatic doffing and donning device in a ring-spinning or ring-twisting machine - Google Patents

Description

The invention relates to methods and devices for monitoring the detection or release of all sleeves or coils of an automatic bobbin changing device of a ring spinning or twisting machine, which simultaneously exchanges a plurality of full bobbins or empty sleeves between spindles and holding pins by means of gripping members, whereby according to Removing the full bobbins from the spindles by means of a light barrier which passes through an area which was occupied by the full bobbins before they were removed from the spindles, it is checked whether all full bobbins have been removed from the spindles.

In the case of automatic bobbin changing devices on ring spinning or twisting machines which simultaneously pull off or plug on a plurality of bobbins, there is a risk that the gripping members of the bobbin changing device will not grip empty bobbins or full bobbins or will not let go of the gripped ones.

If full bobbins to be removed from the spindles of the ring spinning or twisting machine are not grasped and remain on the spindles, in the further course of the changing process an attempt is made to place an empty sleeve on the spindle which is still filled with a full bobbin. This inevitably leads to damage to at least the sleeve, possibly also to the machine or the changing device, which results in undesired downtimes.

In order to avoid this effect, it is already known to provide a light barrier which runs through the area of the full bobbins to be pulled off and which prevents it from being inadvertently left a coil to be withdrawn on the spindle is interrupted and then emits a signal that interrupts the changing process (DE-OS 2 226 077).

If an empty sleeve to be plugged onto a spindle or a full coil that has been pulled off is not released by one of the gripping members and therefore remains on the gripping member, this leads to collisions occurring in the further course of the change process when the intended detection of another empty sleeve or a full coil , which can damage the sleeves, the bobbin changing device or the machine. In addition, in the absence of an empty sleeve, the yarn is wound onto the bare spindle of the ring spinning or twisting machine, from where it can be removed only with great difficulty, time-consuming and costly.

The present invention has for its object to provide methods and devices which not only monitor whether all full tubes have been removed from the spools, but also whether all empty tubes have been delivered by the grippers to the spindles thereby avoiding unwanted winding of thread on empty spindles.

This object is achieved in that after the release of the full bobbins by the gripping members by means of a light barrier which runs through a second area which was occupied by the full bobbins before they were released by the gripping members, it is checked whether all the full bobbins have been released by the gripping organs and / or
that after the removal of the empty sleeves from the holding pins by means of a light barrier which passes through a third area which was occupied by the empty sleeves before they were removed from the holding pins, it is checked whether all empty sleeves have been removed from the holding pins and /or that after the empty sleeves have been released by the gripping members, it is checked by means of a light barrier which runs through a fourth region which the empty sleeves had occupied before the release members by the gripping members, whether all empty sleeves were released by the gripping members.

According to the invention, light barriers are thus provided which run through the area of the empty sleeves or full coils to be released by the gripping members or to be removed from holding pins or spindles and which are interrupted when a sleeve or coil is not released or not removed, trigger a signal and interrupt the further changing process. This advantageously significantly reduces idle times and prevents damage to the changing device or the machine.

In a further embodiment of the invention, the light barriers are activated when the full coils or the empty sleeves should have left the area monitored by the light barriers.

If gripping members are provided which detect both the empty tubes and the full bobbins, a light barrier is sufficient, which alternately scans the empty tubes or the full bobbins, depending on the phase of the exchange process. If, on the other hand, separate gripping members are provided for empty sleeves and for full bobbins in the changing device, a separate light barrier must be provided for each row of gripping members.

The light barriers must run through areas that are occupied by the empty tubes or full coils to be scanned, but are empty after removal.

The light barrier can be arranged stationary on the path of movement of the empty sleeves or full coils or on the component carrying the gripping members.

In a further embodiment of the invention, both the transmitter and the receiver can be arranged on a displacement device with which these parts forming the light barrier can be displaced into the areas to be scanned on the component carrying the gripping members. Furthermore, there is the possibility of making the gripping members and a light barrier, which is movable anyway, so movable that it can guide the light barrier into the area of the full coils to be removed.

In a further embodiment of the invention, the effective area of a light barrier can be shifted without shifting its transmitter and receiver in that the light beam is shifted parallel to itself by mirrors arranged in pairs, which can be folded out of the light beam in pairs. With three pairs of mirrors, two of which are foldable, three can be made with just one light barrier spatially separated areas can be covered in a simple manner.

In a further embodiment of the invention, it is possible to have a plurality of transmitters act on a smaller number of receivers via a plurality of light barriers or, conversely, a larger number of receivers by mirrors from a smaller number of transmitters. For example, a transmitter and a receiver can each be arranged in a stationary manner on the machine frame in such a way that the light barrier formed by them runs through the area of the full coils located on the spindles. By means of mirror pairs, this light barrier can be displaced parallel to itself through empty areas defined by the gripping elements or full coils defined by the gripping elements. In this case, these empty tubes or full spools are scanned on the gripping members in a position that is fixed relative to the machine frame.

According to a further embodiment of the invention, a stationary light barrier can run on the machine frame through the area of the full coils to be removed. At the same time, the component carrying the gripping members contains a light barrier which runs through the area of the empty sleeves gripped. This light barrier can be installed parallel to itself through pairs of mirrors through the area of the full coils held by other gripping members.

Furthermore, according to the invention there is the possibility that the light barriers work with visible or invisible light. In the case of particularly long spindle rows on ring spinning or twisting machines, the use of a laser beam of lower power offers great advantages due to its good bundling. In a further embodiment of the invention, it is possible to make this laser beam flat in cross section by means of a widening optic, in order to avoid that a linear beam is interrupted by a thread which accidentally crosses the beam. Still exists According to the invention, the possibility of using optical fibers in the area of the light barrier.

Fig. 1 bis 17

verschiedene Ausführungsmöglichkeiten der Erfindung in schematischer Darstellung;

Fig. 18 I, III

jeweils eine schematische Ausführungsform der Erfindung;

Fig. 18 II a bis i

die verschiedenen Ablaufschritte bei einem Wechselvorgang;

Fig. 19 und 20

eine andere Ausführungsmöglichkeit der Erfindung in Seiten- und Vorderansicht in schematischer Darstellung.

The invention is described below with reference to exemplary embodiments shown in the drawing. The drawing shows:

1 to 17

different possible embodiments of the invention in a schematic representation;

Fig. 18 I, III

each a schematic embodiment of the invention;

18 II a to i

the different steps in a change process;

19 and 20

another embodiment of the invention in side and front view in a schematic representation.

1 shows a side view of a ring spinning machine 1 with a drive frame 2 and an end frame 3, which is equipped with a gripper bar 4 which can be raised and lowered via a schematically illustrated scissor system 6. A plurality of spindles 7 arranged in two rows are located on spindle banks 8. A transmitter 11 and a receiver 12, which form a light barrier 10, are arranged on the gripper bars 4 carrying gripper members 5. Is after inserting empty sleeves on the spindles 7, a sleeve 9 'has not been released by the gripping members 5 of the gripper bar 4, it is in the area of the light barrier 10, whereby an activation of a control device takes place and the changing process is interrupted. 1 is the Light barrier 10 arranged on the gripper bar 4 carrying the gripping members.

Fig. 2 shows a side view of a ring spinning machine 1 with a light barrier 10, the transmitter 11 and receiver 12 arranged on the machine frame 2 and 3 and by means of a threaded spindle 14 driven by a motor 15 from a position in which they the area of the Spindles 7 monitored full coils, can be shifted into a position in which it monitors the area of the empty sleeves or full coils held by the gripping members of the gripper bar 4. The movement of the transmitter 11 or receiver 12 can take place synchronously, for example by means of stepper motors; however, the drive motors of the threaded spindles 14 can also be asynchronous motors, which transmitters 11 and receivers 12 each move to end positions which are defined by end stops or limit switches. Other mechanical elements for defining the end positions are also possible.

3 shows a plan view of a two-sided ring spinning machine 1 with only one transmitter 11 and one receiver 12, the light barrier 10 of which covers the areas to be monitored on both sides of the machine by means of mirrors 16, 17, 18 and 19. The mirrors 16 and 17 are designed to be pivotable. This results in a significant reduction in effort in a simple manner.

FIGS. 4 to 8 each show sections through the gripper bar 4 and the spindle bench 8 according to FIG. 2. An area is defined above the upper ends of the spindles 7, but still within the outline of full bobbins 13 placed on the spindles a light barrier 10 runs. In this area A, the withdrawal of full bobbins 13 from the spindles 7 can be checked.

Under the gripping members 5, but still within the outline of empty sleeves 9 held on the gripping members, is an area B. defined, through which a light barrier 10 also runs. In this area B, the release of empty sleeves 9 by the gripping members 5 can be checked by means of the light barrier.

Under the gripping members 5, but still within the outline of full coils 13 held on the gripping pins, an area C is defined through which a light barrier 10 runs. In this area, the release of full coils 13 can be checked by the gripping members 5.

In the embodiment according to FIG. 4, in which the gripping members 5 grip both full bobbins and empty sleeves, areas B and C coincide with respect to the gripper bars. The light barrier 10 defined by the transmitter 11 and the receiver 12 can be displaced in the embodiment according to FIG. 4 over the distance indicated by the arrow I between the two areas A and B / C.

In the embodiment according to FIG. 5, light barriers are provided for both areas A and B / C on the stationary machine frame, which are formed by two transmitter / receiver pairs 11, 12 and 11 ', 12'. The area B / C can only be checked in a specific position of the gripper bar 4, in which this area is located within the machine frame of the ring spinning machine 1.

6, the transmitter 11 Sender and the receiver 12˝ forming the light barrier in the area B / C are attached to the gripper bar 4 by means of an arm 21. In this embodiment, the light barrier for the area B / C is connected to the gripper bar 4; A separate light barrier is provided for area A.

In the embodiment according to FIG. 7 again only one light barrier is provided which is connected to the gripper bar 4 via an arm 22 and which monitors the area B / C and by means of the movable one The gripper bar can also be moved to area A using arrow II for monitoring.

In the embodiment according to FIG. 8, a gripper bar 4 with separate gripping members 5 or 5 'for full spools 13 or empty sleeves 9 is provided. Accordingly, the three areas A, B and C are to be monitored individually, which in the exemplary embodiment is carried out with a single light barrier with transmitter 11 and receiver 12 in the machine frame or on the gripper bar 4, which can be moved in accordance with the arrows III.

Fig. 9 shows a side view of a spindle bank 8 and a gripper bar 4 with gripping members 5. Here a transmitter 11 and a receiver 12 are used, the light barrier by four mirrors 16 ', 17', 18 'and 19' between the area A and the area B / C is relocatable. Here, the two mirrors 16 'and 17' can be folded out of the beam path. As can be seen, both the withdrawal of full bobbins 13 from spindles 7 and the release of empty tubes and full bobbins from the gripping members 5 are monitored by a single transmitter 11 and a single receiver 12.

10 shows a schematic cross section through a ring spinning machine 1 with a transmitter 11 and receiver 12 arranged on the machine frame for the area B / C. FIG. 11 shows a cross section through a ring spinning machine 1 with a transmitter 11 or swivel bar 4 shown here. Receiver 12 for the area B / C. As can be seen, the corresponding light barriers in this case again run through areas which are occupied by the empty sleeves or full coils to be scanned, but are empty after removal. Since the bobbin changing device in the embodiment according to FIGS. 10 and 11 operates in such a way that the same gripping members grip both empty sleeves 9 and full bobbins 13, regions B and C again coincide.

12 relates to a schematic representation of the arrangement of transmitter 11 and receivers 12 for two light barriers for areas A and B / C or three light barriers for areas A, B and C on the stationary machine frame.

FIG. 13 is a schematic illustration of an embodiment in which the three areas A, B and C can be scanned by means of only one displaceable transmitter 11 and one receiver 12.

According to FIG. 14 there is the possibility, analogous to the embodiment according to FIG. 9, that a light barrier 10 can be displaced between regions B and C by means of a pair of transmitters / receivers 11, 12 via mirrors. This transmitter / receiver pair is arranged, for example, on the gripper bar 4. For the monitoring of area A, a light barrier 10 'is provided in this embodiment and is arranged in a fixed position on the machine frame.

15 contains a schematic illustration of a solution with which the light barrier 10 can be moved into all three areas A, B and C by means of six mirrors, four of which can be swung out of the beam path, with only one transmitter / receiver pair.

Figures 16 and 17 contain schematic representations of solutions in which the cheaper part of the transmitter / receiver pair 11, 12 dispenses with the mirrors and this part is provided in multiple numbers compared to the more expensive part. 16 is based on the embodiment according to FIG. 4, FIG. 17 on the embodiment according to FIG. 15. Transmitter and receiver can be interchanged, the transmitter 11 being the more expensive part when using lasers.

18 I shows a schematic side view of an embodiment of the invention, from which the arrangement of the areas A, B, C and D can be seen. Here is the area A over the spindle tips, the area D lies over the holding pin for the empty sleeves 9˝, both areas being stationary with respect to the machine frame. Area B lies under the gripping pins for the empty sleeves; area C lies under the gripping pins for the full bobbins; both areas are therefore stationary with respect to the gripper bar 4. When the gripper bar 4 grips empty sleeves 9˝ and full spools 13 with the same gripping pin, areas B and C coincide.

Fig. 18 II a to i shows the individual process steps for monitoring the detection or release of empty sleeves or full bobbins of an automatic bobbin changing device. According to Fig. 18 II a, the gripper bar 4 has moved out of its rest position under the spindle bank 8 over the Spindles moves and is in the process of grasping the full bobbins 13 with the gripping members 5 and pulling them off the spindle 7 with the aid of the scissors system 6 until the position according to FIG. 18 II b is reached. Below the ring bench 8 is a new empty sleeve 9 ', which is arranged on a support pin 20' mounted on a conveyor belt. In this position, the light barrier in area A is used to check whether all the full bobbins 13 have actually been removed from the spindles 7. If this is the case, the full coils 13 are moved downward according to FIG. 18 II c and, according to FIG. 18 II d, are pushed onto the holding pins 20.

It happens that hold-downs, which prevent the upper spindle parts from being pulled out of the spindle bearing housing when the full bobbins are removed, are defective and a spindle upper part 7 is also removed when the full bobbins 13 are removed. This withdrawn upper spindle part then also interrupts the light barrier 10 in area A and leads with an interference signal to the fact that the changing process is interrupted.

After the full bobbins 13 have been released by the gripping members 5 and the gripper bar 4 has moved upwards, the light barrier in area C checks whether all full bobbins have been released and attached to their holding pins 20 on the conveyor belt.

In the position according to Fig. 18 II f and Fig. 18 II g, the gripping members 5 take the empty sleeve 9˝ and pull them from their retaining pins 20 '. Now it is checked by the light barrier in area D whether all empty sleeves 9 'have been tightened by their holding pins 20'. If this is the case, the empty sleeves 9 'are guided in the direction of the arrow into the area above the spindles 7.

As can be seen from FIG. 18 II g, area D is defined via the holding pin 20 'for the empty sleeves 9', but still within the outline of empty sleeves held on these holding pins, which is also penetrated by a light barrier 10. With this light barrier, the withdrawal of empty sleeves 9 'from the holding pin 20' can be monitored. This area D assumes that the holding pin 20 'for the empty sleeves 9˝ and the holding pin 20 for the full spools 13 are arranged in separate, laterally offset rows.

According to Fig. 18 II h and i, the empty sleeves 9˝ are then placed on the spindles 7, this insertion process being monitored by the corresponding light barrier in area B after the empty sleeves have been released.

According to FIG. 18 III there is also the possibility that the light barrier monitoring area A is only activated when the full coils 13 have been moved out of this area. This is advantageous if threads extend in this area in an undesired manner, which would simulate full bobbins 13 which have got caught or got stuck. This avoids undesired working of the individual devices which does not correspond to the actual conditions.

According to FIG. 18 III, there is also the possibility that a further area E, monitored by a light barrier, is used, which lies in the zone which could be coated by an incorrectly pulled out spindle upper part 30. This also prevents damage to the changing device or other machine elements in a simple manner.

In the exemplary embodiment according to FIGS. 19 and 20, optical waveguides 23, 24 and 25 are used in order to monitor the corresponding areas via light barriers 10 in order to carry out a correct changeover process. These optical waveguides are arranged within an optical waveguide channel, the optical waveguides being at least two-wire. One wire works with a light source, not shown, and the other with a photo sensor. The other ends of the two combined wires are directed from the transmitter area 11 to the receiver area 12.

It is possible to use lasers as transmitters, if the beam quality from incoherent light sources is no longer sufficient, to monitor extremely long rows of spindles on ring spinning or twisting machines. Because of their compact design and simple controllability, laser diodes are suitable for this purpose.

It is also possible to use laser light barriers with fiber optics. This system consists of the components light source, light-guiding medium, transmitter and receiver. A coherent light source, for example a helium-neon laser, can be used as the light source. Optical fibers with high transmission in the visible spectral range, preferably single-mode glass fibers with a small core diameter, are used as the light-conducting medium. An optic serves as a transmitter, which bundles and emits the light emerging from the optical fiber. Silicon photo detectors with a large active area and downstream amplifier electronics are used as receivers. This results in the following functionality:
The light emerging from the laser is split into several partial beams by means of beam splitter plates. Each partial beam meets an optic that maps the light onto the end surface of a glass fiber core. Depending on the intended use, the laser light is transmitted through glass fibers of different lengths until it emerges from the fiber at its destination. The light now emerging under a very specific fiber-specific opening angle is refocused or parallelized with the aid of further optics, in the simplest case an achromatic lens. At the same time, the beam is expanded and its beam divergence is reduced. The expanded beam now bridges the work area to be monitored and finally hits the receiver. This effects a switching function as soon as the light beam is covered by an object, for example an empty sleeve 9 or a full coil 13.

The laser light barrier system is used to monitor the changing device on the ring spinning machine. In this case, the take-off of full bobbins 13 or the placement or dropping of empty sleeves 9 is again monitored. This process takes about 5 minutes. During this time, the laser is in the operating phase. However, the laser beam is only released for a few seconds, which the measuring process requires. Transmitter 11 and receiver 12 are installed at the usual positions and provided with cover panels. On the one hand, these cover panels are intended to suppress extraneous light and, on the other hand, to prevent looking into the laser beam.

Claims (19)

1. Method of monitoring the grasping and releasing of all holder tubes or bobbins of an automatic bobbin changing system of a ring spinning or twisting machine, which by means of gripping elements (5) simultaneously exchanges a plurality of full bobbins (13) or empty holder tubes between spindles (7) and holding pins (20),
   wherein after the removal of the full bobbins (13) from the spindles (7) with the use of a photoelectric or light barrier which extends through a region (A) occupied by the full bobbins (13) before their removal from the spindles (7) a test is made as to whether all the full bobbins (13) have been removed from the spindles (7),
   characterised in that
   after the release of the full bobbins (13) by the gripping elements (5) with the use of a light barrier which extends through a second region (C) occupied by the full bobbins (13) before their release by the gripping elements (5) a test is made as to whether all the full bobbins (13) have been released by the gripping elements (5), and/or that after the removal of the empty holder tubes (9'') from the holding pins (20) with the use of a light barrier extending through a third region (D) which had been occupied by the empty holder tubes (9'') before their removal from the holding pins (20) a test is made as to whether all the empty holder tubes (9'') have been removed from the holding pins (20) and/or that after the release of the empty holder tubes (9'') by the gripping elements (5) with the use of a light barrier which extends through a fourth region (B) which had been occupied by the empty holder tubes (9) before their release by the gripping elements (5) a test is made as to whether all the empty holder tubes (9) have been released by the gripping elements (5).
2. Method according to claim 1, characterised in that the light barriers (10) are activated when the full bobbins (13) or empty holder tubes (9'') should have left the region (A, B,C,D) monitored by the light barriers (10).
3. Method according to claim 1, characterised in that a further range or region (E), monitored by a light barrier, is covered by an extended spindle top part (30).
4. Method according to claim 1, characterised in that at least one transmitter (11, 11', 11'', 11''') and/or one receiver (12, 12', 12'', 12''') is used for producing at least two light barriers at different places.
5. Method according to claim 4, characterised in that the light barriers are produced at different places in succession to one another.
6. Method according to claims 4 and 5, characterised in that the light barriers (10) are produced at different places by shifting the same transmitters (11) and/or receivers (12) (Figs. 1, 2).
7. Method according to claim 4, characterised in that the light barriers (10) are produced at different places by mirror deflection of the beam of the same transmitters (11) and/or receivers (12) (Fig. 3, Fig. 9).
8. Method according to claim 1, characterised in that the two scanning operations at the gripping elements (5) for release of all the empty holder tubes (9) or full bobbins (13) are effected in that the respective region (B, C) to be scanned is conducted by means of the movable gripping elements (5) into the same stationary-situated light barrier.
9. Apparatus for carrying out the method according to claim 1, for monitoring the grasping or release of all the holder tubes or bobbins of an automatic bobbin changing system of a ring spinning or twisting machine, with gripping elements (5) for the simultaneous exchanging of a plurality of full bobbins (13) or empty holder tubes between spindles (7) and holding pins, and with a light barrier in a specific region (A), characterised by further light barriers (10, 10') which extend through further regions (B, C, D) passed through by full bobbins (13) or by empty holder tubes or by an extended spindle top part (30).
10. Apparatus according to claim 9, characterised in that a light barrier (10) is arranged on a structure part (4) holding the gripping elements (5) (Fig. 1).
11. Apparatus according to claim 9, characterised in that a light barrier (10) is arranged on a shifting device (14, 15) and is movable between the regions (A) of the full bobbins (13) which are situated on the spindles (7) and the regions (B/C) of the empty holder tubes (9) grasped by the gripping elements (5), or full bobbins (13) (Fig.2, Fig. 4).
12. Apparatus according to claim 11, characterised in that the shifting device comprises a screwthreaded spindle (14) driven by a controlled motor (15).
13. Apparatus according to claim 9, characterised in that a light barrier can be brought by movement of the structure part (4) supporting the gripping elements (5) into the regions (A) of the full bobbins (13) which are situated on the spindles (7) (Fig. 7).
14. Apparatus according to claim 9, characterised in that a light barrier co-operates with pairwise-arranged pivotable mirrors (16', 17', 18', 19') (Fig. 9).
15. Apparatus according to claim 14, characterised by three mirror pairs which are arranged in the range of action of the light barrier and of which at least one (16', 17') is constructed to be capable of pivoting-in.
16. Apparatus according to one of the preceding claims, characterised in that a plurality of pairs of mirrors are associated with a plurality of light barriers (Figs. 14-17).
17. Apparatus according to claim 9, characterised by use of at least one laser beam as a light barrier.
18. Apparatus according to claim 17, characterised by a combination of a laser beam with divergence optics used as a light beam.
19. Apparatus according to claim 9, characterised by use of light wave guides in the region of the light barrier (Figs. 19, 20).

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