CZ2019107A3 - A method of maintaining a supply of yarn in a temporary yarn hopper at a rotor spinning machine work station and the apparatus for this - Google Patents

Abstract

When maintaining the yarn supply in the temporary yarn hopper (10), the drum (101) of the temporary yarn hopper (10) is provided with a drive (102), or the drive take-up roller (51) coupled to the drum (101) is provided with an individual drive (52). The feed device (1) of the strand (2) is provided with an individual drive (13) for feeding the strand (2). The actively driven compensating arm (103) is provided with a drive (104) and the spinning rotor (32) is provided with an individual drive. During the winding of the yarn (4) on the spool (61), according to the information on the amount of wound yarn (4) on the drum (101), the control unit (8) controls the rotational speed of the drive (102) of the drum (101) or an individual drive (52) of the drive take-up roller (51) and the associated drum (101), thereby maintaining a temporary supply of wound yarn (4) on the drum (101) in the desired predetermined range. At the same time, the speed of rotation of the individual drive (13) of the feed roller (11) of the strand (2) of the feed device (1) is controlled to maintain yarn fineness (4), and in the case of individual rotor drive the rotor speed is adjusted to maintain yarn and twist. yarn. At the same time, the individual drive of the compensating arm is controlled to maintain the yarn tension (4) required for the correct construction of the spool (61) and in the case of individual rotor drive (32) the rotor drive speed (32) is adjusted to maintain not only the fineness of the yarn (4) yarn twist (4). The device for performing control operations at the workplace of a rotor spinning machine comprises a temporary yarn hopper (10) (4) by a drum (101).

Description

A method of maintaining a supply of yarn in a temporary yarn hopper at a work station of a rotor spinning machine and an apparatus for carrying out the method

Field of technology

The invention relates to a method of maintaining a supply of yarn in a temporary yarn hopper at a work station of a rotor spinning machine, in which at least the fiber sliver feeder, the temporary hopper drum and the rotary arm of the work station compensating device are provided with individual drives.

The invention further relates to a device for carrying out this method.

Prior art

The rotor spinning machines comprise a plurality of work stations arranged side by side, each of which comprises a fiber sliver feeding device, followed by a unifying device, from which the unified fibers are fed to a spinning rotor in which it is transformed into yarn which is drawn from the spinning rotor by a take-off rotor. device and in the winding device it is wound on a spool. A yarn compensation device with a temporary yarn hopper can be arranged between the take-off and the winding device, and a yarn distribution device is arranged in front of the winding device. Alternatively, the take-off device can be combined with a temporary yarn hopper. The presence and quality of the spun yarn is monitored by a yarn quality and presence sensor arranged in front of the yarn take-off device, which is connected to the control unit of the machine workplace.

When winding the yarn on rotor spinning machines, the sleeve or the already wound spool abuts at the work station on a drive roller which is mounted on a continuous drive shaft common to all work stations arranged on one side of the machine and which is coupled to a central drive arranged in the drive unit. in the side of the machine. This solution has above all economic advantages, as the winding system is common to the entire side of the machine and the cost per job can remain low. When spinning a spinning unit on a new core or on a spool after a yarn break during the winding process, it is necessary for a successful spinning process to create the necessary supply of yarn to return the yarn to the spinning rotor. Advantageously, a temporary yarn hopper according to a known solution, for example DE3415447, EP2216432 or EP1460015, can be used for this function. Also during the standard winding process, it is advantageous to create and maintain a certain supply of yarn on the drum of the temporary yarn hopper, which serves to compensate for the differences in the instantaneous take-off and winding speeds. When winding yarn, the spool in conventional winding systems has a constant circumferential speed, determined jointly for all spinning stations at the speed of the common winding shaft, and when distributing yarn, the yarn tension changes at the workplace between the take-up device and the take-up device due to variable distribution speed. .

In current rotor spinning machines, it is preferred to create yarn windings of a predetermined constant length. The spools are therefore wound gradually over a longer interval, so that there are spools of various diameters on the machine, from an empty tube to a full spool. For high-quality winding of the yarn on the spool, the phenomenon during the construction of the spool is suitable to regulate the tension of the yarn between the take-off and winding device, and thus to achieve optimal conditions for its construction. However, if the spool is driven by a drive roller on a continuous shaft during winding, this cannot be achieved by changing the winding speed, as each spool diameter would require a different setting. Even worse is the situation with conical bobbins, where it is necessary to take into account the change of the middle point of yarn withdrawal due to the changing conicity during the increase of the winding. For this reason, it appears advantageous to provide the spinning unit of the rotor spinning machine with a temporary yarn hopper combined with a take-off device. However, due to small deviations in the winding and withdrawal speeds, or due to changes in the speed of the actively driven compensating arm of the intermediate hopper

- 1 EN 2019 - 107 A3 yarn To achieve the optimal tension of the wound yarn, the amount of yarn in the intermediate hopper may be reduced or increased outside the required limits. Due to the fact that the winding speed of machines with a continuous shaft for driving winding devices with a central drive unit cannot be changed for individual spinning stations, it is necessary to align the take-off and winding speeds in other ways.

Various methods are known for maintaining a supply of yarn in a temporary yarn hopper at a station of a rotor spinning machine and apparatus for carrying out the method.

E.g. DE3415447 discloses textile machines equipped with a yarn hopper arranged at a spinning point in a yarn path between a spinning unit and a yarn winding unit, the mechanical rotary yarn hopper being arranged behind the take-up rollers. The essence of the solution according to the present invention lies in the fact that the mechanical rotary hopper is coupled by a single take-up roller, which is followed by a winding roller with yarn distribution, and is mounted coaxially on the driven take-off roller from its front side. The object of the invention is to eliminate the problems of drawing and winding, as well as the return of the yarn when spinning a spindleless spinning machine provided with a mechanical rotary hopper behind the take-up rollers.

CZ 303880 discloses an embodiment with a drum intermediate yarn hopper, the essence of which consists in that the driven rotary drum is coupled to a first drive formed by an electric motor and the compensating rotary arm is coupled to a second drive formed by an electric motor, both motors being connected to a control system spinning machine. The advantage of this solution is that the swivel arm is driven by a separate motor, which is controlled by the machine control system so that the speed of the arm and the generated torque are independently controllable if necessary regardless of the speed and direction of rotation of the working surface of the hopper (drum). and thus a wider possibility of using the hopper in the automation of service operations at the workplace of the textile machine is achieved.

The disadvantage of these known devices is that they do not solve the situation where due to the accumulation of small fluctuations and deviations of winding and withdrawal speed, or due to changes in speed of actively driven compensating arm to achieve optimal yarn tension during winding, the amount of yarn in the temporary hopper may decrease or increase. required limits even during continuous spinning.

CZ 306035 also describes a rotor spinning machine with a number of juxtaposed workstations, each of which comprises a spinning unit, the main components of which are a fiber sliver feeder, a separating device and a spinning rotor from which yarn is discharged by a take-off device and wound coil. During winding, the yarn tension between the take-up and take-up device is monitored and the yarn take-up speed is changed during spinning to maintain the desired yarn tension between the take-up device and the take-up device. . The disadvantage of this method of winding the yarn is that the fineness of the spun yarn is partially affected and the device requires the installation of appropriate sensors at each spinning station, thus increasing the production and operating costs of the machine.

The object of the invention is to eliminate or at least alleviate the disadvantages of the prior art in machines with a continuous spool drive shaft during winding.

The essence of the invention

The object of the invention is achieved by a method of maintaining a supply of yarn in a temporary yarn hopper at a spinning station of a rotor spinning machine, the essence being that during winding with changing speed of individual drive of the temporary yarn hopper drum or individual drive of the take-up roller coupled to the temporary yarn hopper drum

-2 CZ 2019 - 107 A3 keeps the amount of wound yarn on the drum of the temporary yarn hopper in the required predetermined range, i.e., the actual take-off speed changes, and at the same time changes the rotational speed of the individual sliver drive at the feeder. slightly increases or decreases the amount of fibers fed to the spinning rotor and maintains the ratio of feed and take-up speed, thereby maintaining a constant yarn fineness. There are slight changes in the number of turns, which are negligible for the spinning rotor technology due to small changes in speed. In the case of an individual drive of a spinning rotor, it is also possible to regulate its speed so that the yarn twist is precisely maintained. This makes it possible to maintain an optimal supply of yarn on the drum of the temporary yarn hopper, from which small speed variations are compensated between the wound and drawn yarns during spinning. At the same time, the individual control of the drive of the compensating arm maintains the amount of tension of the wound yarn during winding on the cross-wound spool for the correct construction of the spool winding. This is particularly advantageous when winding yarn on a conical bobbin. The workstation control unit, which controls the rotational speeds of the temporary yarn hopper drum, receives information about the amount of yarn in the hopper from the drum filling sensor (eg optical), or the amount of yarn in the hopper is determined by integrating the speed difference between the temporary hopper drum drive and the compensating arm. system.

The essence of the device for carrying out the method according to the invention lies in the fact that the control unit of the spinning station, into which information about the extent of the required yarn supply on the drum is entered by the superior machine control system or machine operator, subsequently regulates the amount of yarn in the intermediate hopper as described above. The control unit further comprises outputs for controlling the individual drives, further comprising an input for a communication line which supplies information on the amount of yarn in the temporary yarn hopper.

The initial yarn backup in the temporary yarn hopper is usually performed by the operator during the spinning process, in which the spool wound above the drive roller rotates in the opposite direction to the winding process, and a predetermined length of yarn is unwound from the spool. temporary yarn hopper drum. However, this supply of yarn may change during the spinning process due to variations in the winding and take-up speeds, or due to changes in the speed of the actively driven compensating arm to achieve the optimal yarn tension.

Explanation of drawings

To illustrate the method and device according to the invention, the drawings show FIG. 1a showing a diagram of the drives of the basic units of the workstations of a rotor spinning machine without take-up rollers with a temporary yarn hopper, FIG. Fig. 2a is a side view of the drives of the basic workstations of the rotor spinning machine workstations without take-up rollers with a temporary yarn hopper, Fig. 2b is a side view of the drives of the basic workstations of the rotor spinning machine workstations with take-off rollers and temporary yarn magazine. Fig. 3a is a diagram of a device according to the invention for controlling the drives of the base units of workstations of a rotor spinning machine without take-up rollers with a temporary yarn hopper;

Examples of embodiments of the invention

The rotor spinning machine comprises a plurality of work stations arranged side by side, each of which comprises a fiber sliver feeding device 1, a spinning unit 3, which comprises a fiber sliver separating device 31 and a spinning rotor 32. The sliver feeding device 1

-3GB 2019 - 107 The A3 fibers comprise a feed roller 11, which is coupled to a drive 13 for feeding the fiber strand 2. The drive 13 for feeding the fiber strand 2 is coupled to the control unit 8 of the respective work station. In an embodiment not shown, the spinning rotor 32 is coupled to an individual drive, for example according to EP6466021 or DE4104 250. The individual drive of the spinning rotor 32 is coupled to a workstation control unit 8. A yarn 4 is formed in the spinning rotor 32 in a known manner, which is pulled out of the spinning rotor 32 by a take-off device 5 and guided to a winding device 6, in which it is wound on a spool 61 which is in contact with the drive roller 62 during winding. of each work station is mounted on a drive shaft 63, which is common to a number of juxtaposed work stations. The drive shaft 63 is coupled to the drive 64 and rotates at a constant speed during winding, so that the coils 61 of the individual workstations have a constant peripheral speed. In front of the winding device 6, the yarn 4 passes through a distribution device 7, which in a known manner distributes the yarn 4 over the entire width of the bobbin 61. The yarn take-off device 5 comprises a drive take-off roller 51 coupled to an individual take-off drive drive 52. 51, the drum 101 of the temporary yarn hopper 10 is coupled, on which an actively driven compensating arm 103 is arranged with a drive 104. The individual drive 52 of the towing device 5 and the drive 104 of the compensating arm 103 are connected to the workstation control unit 8, as shown in FIG. 1b, 2b. The control unit 8, as shown in Fig. 3b, which is supplied from the source 9 in a known manner, comprises a drive control unit 109 with a source feed drive controller 131, an individual yarn take-off drive controller 521, a compensating arm drive controller 1041 and optionally a controller. 1061 individual rotor drive.

In another arrangement of the spinning station according to FIGS. 1a, 2a, the drive drive roller 51 with individual drive 52 and the hinged pressure take-up roller 53 of the take-off device 5 are replaced by a temporary yarn hopper 10 representing the function of the take-off device 5. The temporary hopper 10 comprises a drum 101. which is driven by an individual drive 102 and an actively driven compensating arm 103 arranged thereon is driven by a drive 104. The drive 102 of the drum 101 and the drive 104 of the compensating arm 103 are connected to a workstation control unit 8 as shown in Fig. 3a, which comprises a drive control unit 109 with a source feed drive controller 131, a drum drive controller 1021, a compensating arm drive controller 1041, and optionally an individual rotor drive controller 1061.

The method of controlling the device for maintaining the yarn supply 4 on the drum 101 is carried out in such a way that the control unit 8 continuously receives information on the amount of yarn 4 in the intermediate yarn container 10 from the filling sensor 105 (e.g. optical) of the drum 101, or with integration from the speed difference. of the drive 102 of the drum 101 and the drive 104 of the compensating arm 103 evaluates the amount of yarn 4 in the intermediate hopper 10. By continuously comparing the information with a preset value of the required filling range of the drum 101 of yarn 4, the control unit 8 increases / decreases the drive rotation speed by the individual yarn take-off drive controller 521. 52 of the take-off roller 51 and the drum 101 coupled thereto as shown in Figs. 1b, 2b, 3b or according to another arrangement shown in Figs. 1a, 2a, 3a, the drum drive controller 1021 increases / decreases the rotation speed of the drive 102 of the drum 101; to create and maintain a supply of yarn 4 on the drum 101 within the prescribed range. Depending on the magnitude of the change in speed of the drive 52 of the take-up roller 51 or the drive 102 of the drum 101, the control unit 8 changes the rotational speed of the drive 13 of the feed roller 11 of the fiber sliver 1 into the spinning unit 3 so as to maintain the fineness of the yarn produced. the number of twists in the yarn 4 which occur is negligible, but in the case of an individual drive of the spinning rotor 32 the speed of the spinning rotor 32 is adjusted so that in addition to the fineness of the yarn 4 the yarn twist 4 is precisely maintained. arms 103 so as to maintain the yarn tension 4 required for the correct construction of the bobbin winding 61.

In the exemplary embodiment of the device according to the invention shown in Fig. 3b, the supply of yarn 4 on the drum 101 is controlled by a control unit 8, into which it is a superior communication control system.

The control unit 8 according to the exemplary embodiment further comprises a drive control unit 109, which comprises a drive control unit 109, which comprises a control unit of the spinning machine and / or a control system of the spinning station section or by operating the machine via the input unit 108. the source drive actuator 131, the drive 104 of the compensating arm 103, the drum drive 102 (FIG.

3a) or the control module 521 of the individual drive 52 (Fig. 3b) of the towing device 5. In case an individual drive 106 of the spinning rotor 32 is arranged on the spinning unit 3, the drive control unit 109 comprises an individual rotor drive controller 1061. the drive 106 of the spinning rotor 32 for maintaining the yarn twists 4. The control unit 8 further comprises an input which supplies information about the amount of yarn 4 in the yarn intermediate container 10 from the filling sensor 105 of the drum 101. or the amount of yarn 4 on the drum 101 is determined by integrating from the difference in speed of the drive 102 of the drum 101 and the drive 104 of the compensating arm 103 by feeding information on the speed of the drive 102 and the drive 104 to the input of the control unit 8.

Industrial applicability

The invention is useful in controlling the operation at the workstations of rotor spinning machines with at least partially arranged individual drives of the work units.

Claims (7)

PATENT CLAIMS A method of maintaining a supply of yarn (4) on a drum (101) of a temporary yarn container (10) at a spinning station of a rotor spinning machine, wherein a fiber strand (2) is fed to a spinning unit (3) in which yarn (4), which is withdrawn and passed through the drum (101) of the temporary yarn container (10) to the yarn winding device (6), where it is wound at a constant speed onto the spool (61), while being monitored and controls the filling level of the drum (101) of the temporary yarn container (10) (4), characterized in that the withdrawal speed of the yarn (4) from the spinning machine is simultaneously controlled according to the filling level of the drum (101) of the temporary yarn container (10). of the unit (3) and the speed of feeding the fiber strand (2) into the spinning unit (3), thereby maintaining the desired level of filling of the drum (101) of the temporary yarn hopper (10) while maintaining the basic parameters of the yarn (4) being produced. Method according to claim 1, characterized in that the drive (104) of the compensating arm (103) of the temporary yarn container (10) is controlled at the same time to maintain the yarn tension (4) for correct winding construction on the spool (61). Method according to Claim 1 or 2, characterized in that the rotational speed of the spinning rotor (32) is controlled, thereby improving the parameters of the yarn (4) produced. 4. Apparatus for maintaining the size of the yarn supply (4) on the drum (101) of the temporary yarn hopper (10) at the spinning station of the rotor spinning machine, which comprises a feed device (1) of the fiber strand (2) to the spinning unit (3). behind which a spinning rotor (32) is arranged in the direction of travel of the fibers, behind which a yarn take-off device (5) (4) with a temporary yarn hopper (10) (4) is arranged, behind which a yarn winding device (6) ( 4) on a spool (61), the feed device (1) of the fiber strand (2), the yarn take-off device (5) (4) with the temporary yarn hopper (10) (4) being provided with individual drives coupled to the control unit (8) and the temporary yarn container (10) is associated with a system for monitoring the filling level of the drum (101) of the temporary yarn container (10) connected to the control unit (8), characterized in that the control unit (8) is provided with an actuator adapted to simultaneously control the take-off speed of the yarn (4) and the feed speed of the sliver (2) to the spinning unit (3) according to levels of filling the drum (101) of the temporary container (10) with yarns (4) and for maintaining a predetermined range of yarn (4) on the drum (101) of the temporary container (10). Device according to claim 4, characterized in that the control unit (8) is provided with an actuator for maintaining the yarn tension (4) for correct wound construction on the spool (61) by controlling the drive (104) of the compensating arm (103) of the temporary hopper (10). ) yarn (4). Device according to claims 4 and 5, characterized in that the control unit (8) is provided with an actuator adapted to control the rotational speed of the spinning rotor (32). Apparatus according to any one of claims 4 to 6, characterized in that the spinning station control unit is coupled to the control system of the rotor spinning machine, and / or the control system of the spinning station section.