CH686313A5 - Method and apparatus for a ring spinning or twisting machine About guards. - Google Patents

Description

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description

6. The invention relates to a method and a device for monitoring a ring spinning or twisting machine, during the automatic removal of full bobbins and the insertion of empty tubes according to the preamble of claims 1 and 6 respectively.

A method and a device for monitoring the detection or release of all sleeves or bobbins on an automatic bobbin changing device of a ring spinning or twisting machine are already known (DE 3 836 330 A1). Here, a number of full bobbins or empty sleeves are simultaneously pulled off the spindles or holding pins by means of gripping elements, a light barrier running through the area of the full bobbins to be pulled off being present which is released by a bobbin or sleeve which has not been removed or is not released to release a Error signal is interrupted.

In the post-published DE 4 037 312, a device for gripping an empty or wound sleeve is proposed, which has a sensor for the presence or absence of an empty sleeve or a full coil, which is connected to a signaling device.

In addition, a device for placing and removing coils relative to the spindles of a spinning machine is known as prior art, which uses pneumatic sensors which generate a first, a second and a third pneumatic signal (DE 2 802 805 A1). This known device requires a structurally complex fine-tuning of the generation of different pneumatic signals. In addition, there is a further design effort insofar as - as in another known prior art (EP 0 306 285 A1) - the gripping elements are each designed with two arms and are pneumatically actuated for the corresponding gripping actuation.

In these constructions, each position of the automatic bobbin changing device is queried by an individual sensor for the detection or non-detection of a cop or a sleeve, a signal being output in the event of an error in the course of the changing process. The signal can interrupt the change process or call an operator.

The disadvantage of avoiding malfunctions and therefore preferred interrupting the change process has the disadvantage that the work of the entire machine is interrupted if the operator does not intervene quickly or cannot intervene soon due to other stress. This results in an undesirable loss of production. On the other hand, damage can occur or time-consuming work interventions can be necessary without interrupting the changing process.

The object of the present invention is based on a construction in which the individual spinning positions are checked for the presence or absence of a sleeve (DE 3 932 664 A1). After each doffing process, an operating robot is used first

Check the spinning positions to see whether a spinning sleeve is attached to the respective spindle or not. A light barrier is used, the light beam of which is reflected by a reflector in the absence of a spinning sleeve. The light barrier supplies corresponding information to an electronic control unit which, in the absence of a spinning sleeve, actuates a roving stop device. In this known construction, the check is placed on the individual spinning positions of the ring spinning machine.

In contrast, the present invention is based on the object of designing a method or a device of the type mentioned at the outset in such a way that the removal process is interrupted in the area of the doffing device if an error message is present.

This object is achieved according to the invention:

a) in the method mentioned at the outset by the characterizing features of claim 1 and b) in the device mentioned at the outset by the characterizing features of claim 6.

This has the advantage that, by differentiating the error messages in the area of the doffing device, only that work station where the error occurs is shut down, whereas the changeover process continues unimpeded. This prevents undesired production downtime at an early stage and the machine or the bobbin changing process can continue to run, with the exception of the faulty work station.

Advantageous further developments of the method according to the invention result from the subclaims.

The device for carrying out the method is characterized by a control device connected to the sensor devices and a bobbin change sequence control device, with a first discriminator stage for comparing the sensor signals of the sensor devices with set signals of the bobbin change sequence control device and for emitting an error signal in the event of a mismatch and with a second discriminator stage for Converting error signals into different shutdown signals depending on position signals of the bobbin change sequence control device.

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

Fig. 1-3 each a schematic front view of a ring spinning machine in different phases of the bobbin changing process.

1, a ring spinning machine 1 has a number of spinning positions, only a few of which are shown in the region of the end frame 35 of the ring spinning machine. A spinning station is to be understood to mean all the working elements of the ring spinning machine that work together to produce a single thread; these are in particular roving bobbins 25, 26, 28 (FIGS. 2, 3), a drafting system, not shown, loaded in a spindle bank 3

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gerte spindles 4 and a device for stopping a relevant spinning station.

In the illustrated and described embodiment, this device consists of a sliver stop device 32, 33 (FIG. 2), by means of which the roving drawn off from a roving bobbin can be stopped and the further supply of roving can be interrupted. The type and mode of operation of such sliver stop devices are known and are therefore not described in detail here.

Gripping points 7 are provided on a gripper bar 6 of a bobbin changing device, denoted overall by 5. The gripper bar 6 can be raised and lowered in a manner known per se by means of a drive device 13 and can move from the upper position shown in FIG. 1 to the lower position shown in FIG. 2.

A transport device 9 with a rotating conveyor belt is arranged below the spindle bank 3 and has pins 10 for receiving coils 11 or empty sleeves 12 at a distance of half the spindle pitch. The drive device of the transport device 9 is not shown; however, it is connected to a spool change sequence control device 14, which is located in the machine end frame 35.

In the machine end frame 35 of the ring spinning machine 1, a control device 16 with a first discriminator stage 17 and a second discriminator stage 18 is also arranged.

Each gripping point 7 has a sensor 15 for determining the presence or absence of an empty sleeve 12 or a full spool 11. The sensors 15 are connected to the control device 16 via a line 24. In this case, each gripping point 7 can be provided, for example, with a tensioning element (not shown in more detail) which can be moved against the empty sleeve 12 or full spool 11 resting against a stop, the tensioning element being connected to the sensor 15 and activating it accordingly. Gripping points designed in this way are described and illustrated in German patent application P 4 037 312.

The general process of changing the bobbin now proceeds as follows: During the production process, the transport device 9 conveys a complete set of empty tubes 12 in a corresponding position along the ring spinning machine 1 on the pins 10 in succession. The pins 10 equipped with empty tubes 12 stand offset in the starting position of the bobbin changing device by half a spindle pitch relative to the axes of the spindles 4.

The actual doffing process begins after spinning, i.e. after completion of the production process: after the gripper bar 6 has been lowered, the gripping points 7 pull the full bobbins 11 off the spindles 4 and then move into the lowest position, in which they place the full bobbins 11 on the corresponding empty pins 10 of the transport device 9 Off.

After lifting the gripper bar, the transport device moves sideways by half a division, so that the empty sleeves 12 are moved into their doff position. The gripping points 7 now grasp the empty sleeves 12, pull them off the pin 10 and, after reaching the upper position of the gripper bar 6 and lowering them again, place them on the spindles 4 of the spindle bench 3.

The functionally correct sequence of the doffing can be monitored by means of a light barrier 29, which consists of a transmitter 30 and a receiver 31.

The control device 16 is connected to the bobbin change sequence control device 14, a line 19 for transmitting a bobbin change stop signal, a line 20 for transmitting position signals of the bobbin change sequence control device and a line 21 for transmitting the signal to be explained in more detail below Coils or cores captured »or« All coils or cores released ».

The first discriminator stage 17 is also connected to the receiver 31 of the light barrier 29 and the individual gripping points 7 or the sensors 15 individually assigned to them. The sensor signals (actual signals) coded at the spinning position are transmitted to the first discriminator stage 17 via the line 24.

The second discriminator stage 18 is connected via a line 22 to the match stops 32, 33, 34 etc.

In Fig. 1 the working phase is shown, in which the gripping elements 7 have pulled the full bobbins 11 from the spindles 4 of the ring spinning machine and the empty sleeves 12 are on pins 10 of the transport device 9.

The situation here is that the sensor of the gripping element VI does not feel a coil after the full coil 11 has been removed and thus emits a sensing signal to the first discriminator stage 17 via the line 24.

At the same time, the first discriminator stage 17 is given a desired signal by the bobbin change sequence control device 14 that the gripping elements 7 should detect bobbins in this phase of the bobbin change and 15 bobbins should be sensed accordingly by the sensors. Since this is in any case not the case with the gripping element IV, an error signal 23 is generated in the first discriminator stage 17 and passed on to the second discriminator stage 18.

This second discriminator stage 18 is given a signal by the spool change sequence control device 14 that the pull-off process is in the phase in which the full spools 11 have been pulled off the spindles 4. Since it must be assumed that the coil not felt on the gripping element IV could have remained on the spindle 4 and the insertion of an empty sleeve on the coil remaining on the spindle could lead to damage in the further course of the coil changing process, the second discriminator stage 18 indicates this phase of the pull-off process via line 19, a command signal for interrupting the bobbin changing process to the bobbin changing sequence control device 14.

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In another embodiment of the invention, it can be provided that the area above the spindles 4 is scanned by a light barrier 29 for remaining coils 11. This exemplary embodiment is shown in FIG. 1: If the light barrier 29 detects that there is no full bobbin 11 on the spindle 4, whose associated sensor 15 has triggered a sensing signal, the interruption of the bobbin changing process can be omitted - there is nothing to be said against this to populate the spindle in question with an empty sleeve as the change process continues.

If a full bobbin 11 remains on the spindle, there is the possibility (not shown in more detail) of triggering an optical or acoustic warning signal, which, for example, causes an operator to remove the full bobbin 11 from the spindle, thereby causing undesirable damage in the course of the function avoid.

According to the invention, it can therefore be provided that the light barrier 29 checks whether a coil 11 has actually remained on a spindle 4. If this is not the case, the output of an error signal 23 by the first discriminator stage 17 is prevented by the signal from the receiver 31 of the light barrier 29 which is applied to the first discriminator stage 17.

The bobbin changing process is also interrupted in a further case, not shown in the figures, namely if, after the full bobbins 11 have been deposited on the depositing points 8 of the transport device 9, a coil remains at one or more gripper points 7.

In this case too, an error signal 23 is generated in the first discriminator stage 17 from the sensing signal of the sensor 15 of the corresponding gripper point by comparison with the desired signals for all gripper points and according to position signals of the spool change sequence, from which an instruction signal is generated in the second discriminator stage 18 is formed to interrupt the peeling process.

The situation in FIG. 2 assumes that after the empty sleeves 12 have been pulled off the pins 10 of the transport device 9 on the gripper bar 6, a sleeve 12 is not felt, as is the case, for example, with the gripper point II (sleeve is not present) or with the Gripper point VIII (sleeve 12 could not be detected) is the case.

The consequence of this is that no empty tubes are attached to the spinning positions in question. In this case, damage can only occur if the spindles of these spinning positions are spun with yarn, which of course cannot be removed during the next bobbin changing process and onto which no empty sleeve may be attached during the next removal process. It is therefore sufficient if it is prevented that the relevant spinning stations are still in operation; It is not necessary to interrupt the bobbin changing process.

The sensory signals emitted by the sensors 15 of the gripper points II or VIII via the line 24 are compared in the first discriminator stage 17 with the desired signal given by the spool change sequence control device 14, which provides for the detection of sleeves at all gripper points. Since this is in any case not the case for spinning stations II and VIII, spinning station-coded error signals 23 are emitted from the first discriminator stage 17 to the second discriminator stage 18.

There these error signals are compared with the position signal given to the second discriminator stage 18 for the given phase of the bobbin changing sequence. In this case, the second discriminator stage 18, in the wake of the error signals that have been applied, gives command signals, coded by the spinning station, via the line 22 to the rifle stop devices 32 and 33 of the relevant spinning stations II and VIII, by means of which these spinning stations are stopped in the sense that they no longer provide a fuse.

Fig. 3 shows the placement of the empty sleeves 12 on the spindles 4 of the spindle bank 3. As can be seen, the gripping point IV assigned to the relevant spinning station 4 did not release the sleeve 12 when it was placed on the spindle 4: Even in this case only those disadvantages described above occur; it is therefore also sufficient here to shut down the relevant spinning position, for example via the match stop device 34. With regard to the gripping points II and VIII, the sleeves 12 are missing here. Also, analogously to the process according to FIG. 2, the relevant spinning positions are shut down via the sliver stop devices 32 and 33 assigned to them.

By comparing the sensor sensor signal with the target signals of the bobbin change sequence control device 14 in the two discriminator stages 17 and 18, a spinning station-coded command signal is ultimately generated in the second discriminator stage 18 and forwarded to the relevant spinning stations.

After each removal and deposition of the bobbins and the empty tubes, a check is carried out to determine whether or not bobbins or empty tubes are being detected, and accordingly, depending on the phase position of the bobbin changing process.

1. Command signals for stopping individual spinning stations are formed and, accordingly, only individual spinning stations are shut down if a) after the removal of empty sleeves 12 from the pins 10 of the transport device 9, no empty sleeve is felt to be detected or b) after the placement of empty sleeves 12 on the spindles 4 an empty sleeve 12 is felt to be captured; or

2. Command signals to interrupt the pulling-off process and accordingly the pulling-off process are interrupted if c) after pulling out full bobbins 11 from the spindles 4, no full bobbin is felt to be detected and it must be feared that the bobbin has remained on the spindle or

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d) after placing full bobbins 11 on the pins 10 of the transport device 9, a full bobbin is felt to be detected.

In the process sequence according to the invention, a comparison of the sensing signals of the individual gripping points 7, i.e. the actual signals "occupied" or "not occupied" with the target signals for all gripping points 7, i.e. "All occupied" or "All unused" instead, whereby error signals 23 are formed if necessary.

In a second evaluation in the second discriminator stage 18, the error signals 23 of the first evaluation stage are compared with position signals of the coil change sequence.

Depending on these position signals, either a signal to interrupt the pulling process, i.e. Cases c or d or a signal for stopping only the spinning station that caused the formation of the error signal of the first evaluation stage, i.e. Cases a and b.

It is also possible, according to the invention, to primarily determine, depending on the phases of the bobbin changing sequence, that if an error signal is generated secondarily in the given phase of the bobbin changing sequence, this as a signal for interrupting the removal process or as The signal to stop the work is effective. This is also a two-stage evaluation, but the chronological sequence of the stages is reversed in contrast to the aforementioned embodiment.

Both possibilities have in common that the spinning position-coded error signals are formed from the comparison of the sensing signals of the individual gripping points with target signals for all gripping points and that, depending on position signals of the spool change sequence, either an instruction signal for interrupting the pull-off process or a spinning location-coded command signal for stopping from an error signal only that spinning station which caused or has caused the formation of the error signal is formed.

The key points of the invention are therefore:

- Spinning station-specific detection of malfunctions,

- comparison of the sensing (actual signals) with (sensing) target signals for generating spinning position-coded error signals,

- Comparison of the error signals with position signals for generating

- either, if permissible, spinning station-coded shutdown (command signals) only for individual spinning stations or

- Interrupt (command) signals for the entire bobbin changing process.

Claims (8)

Claims 1. A method for monitoring a ring spinning or twisting machine during the automatic removal of full bobbins and the insertion of empty tubes by means of a doffing device provided with gripping points, The individual spinning positions are checked for the presence or absence of a sleeve and the corresponding spinning position is stopped as a function of an error signal, characterized in that the error signals (23) from the comparison of the sensing signals of the individual gripping points (7) of the doffing device Desired signals are to be formed for all gripping points and that, in accordance with position signals of the bobbin changing sequence, either a command signal to interrupt the removal process or the command signal to stop the corresponding spinning station is formed from an error signal. 2. The method according to claim 1, with additional, total scanning of the settling points of all spinning stations for the presence or absence of a sleeve or spool, characterized in that an unoccupied signal of a gripping point (7) by scanning the settling point (2; 8) at least the gripping point (7) which triggers the unoccupied signal is checked for remaining of the sleeve (12) or coil (11) at this setting point (2; 8) and, if not used, also the setting points (2; 8) Error signal (23) is not issued. 3. The method according to claim 1, characterized in that if a gripping point (7) is felt to be unoccupied after a withdrawal requiring all gripping points (7) to be occupied, or if a gripping point (7) is felt to be occupied an error signal (23) is emitted when the gripping points (7) are not occupied. 4. The method according to claims 1 and 3, characterized in that by an error signal (23) after removing the full coils (11) from the spindles (4) or an error signal (23) after depositing the full coils (11) on the Settling points (8) of the transport device (9) a signal to interrupt the pulling process is triggered. 5. The method according to claims 1 and 3, characterized in that by removing the empty sleeves (12) from the pin (10) of the transport device (9) or after placing the empty sleeves (12) on the spindles (4) triggered error signal (23) a signal to stop only the relevant spinning position is triggered. 6. Device for carrying out the method according to claim 1 on a ring spinning or twisting machine with a device for automatic bobbin change and with sensor devices by means of which the occupancy or the non-occupancy of each gripping point of the device for automatic bobbin change can be felt can, characterized by a control device (16) connected to the sensor devices (15) and a bobbin change sequence control device (14) with a first discriminator stage (17) for comparing the sensor signals of the sensor devices (15) with set signals of the bobbin change sequence control device (14) and for emitting an error signal (23) in the event of a mismatch and with a second discriminator stage (18) for converting error signals into different command signals as a function of position signals of the spool change sequence control device (14). 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 5 9 CH 686 313 A5 7. The device according to claim 6, wherein the automatic bobbin changing device has a gripper bar equipped with the gripping points, characterized in that the sensors (15) are arranged on the gripper bar (6). 8. The device according to claim 6 for carrying out the method according to claim 2, characterized by a with the control device (16) connected to the light barrier (29) for sensing coils (11) or sleeves (12) left behind on deposit points. 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 6