CN105683074A - Godet and method for controlling a godet - Google Patents

Abstract

The invention relates to a godet for guiding a thread and to a method for controlling a godet and a method for operating a godet. The godet and the method are based on the fact that a godet casing (1), driven by an electric drive (2), of the godet is used in order, given a corresponding design of the electric drive (2), to restart the drive, following an interruption to operation, by way of a manually generated rotary movement of the godet casing (1). The drive can be activated without additional tools following an interruption to operation.

Description

Godet and godet control method

The invention relates to a godet for guiding a yarn according to the preamble of claim 1 , a godet control method according to the preamble of claim 10 and a godet operation according to the preamble of claim 16 method.

It is known in yarn production and processing that the yarn is guided in one or more partial turns on the peripheral surface of the rotating godet housing of the godet for guidance, transport or orientation. This godet guarantees yarn transport on the textile machine or in the production process. For example, in texturing processes for orientation and texturing, the untreated yarn is provided as a feed bobbin and is guided in texturing machines through a plurality of godets arranged one behind the other in a work station. At the station, the individual yarns are oriented and textured and then wound into bobbins.

Such godets and godet control methods are disclosed, for example, in WO2007/134732.

For guiding the yarn, known godets have a godet housing that can be driven and connected to an electric drive. In this case, the yarn is guided on the peripheral surface of the driven godet housing. There is then the danger that, for example, sagging or misfeeds will occur during the lap change in the downstream winding device or that yarn breaks will even occur in the workstations. However, such a change in yarn tensile stress during the yarn guidance can lead to undesired yarn loops on the driven godet housing of the godet. In order to achieve the shortest possible interruption times, in the known godet the yarn guidance of the godet housing is monitored by a loop sensor to allow a quick shutdown of the electric drive. After the yarn loops on the circumference of the godet housing have been removed, the loop sensor is adjusted to its initial position, as a result, the interrupted power supply of the electric drive is restored, so that a restart of the drive is possible. Here, the coil sensor can be used directly as a switch for restarting the electric drive.

In principle, however, the prior art also discloses godets in which the activation of the electric drive is carried out via a separate switch. Whether or not the switching takes into account the additional function of winding monitoring, complex wiring between the switch and the electric drive is required. The operator carrying out the switching operation places the yarn on the godet circumference again during the interruption of operation.

It is therefore the object of the invention to improve a godet of the aforementioned type and a godet control method of the aforementioned type in such a way that the electric drive of the godet can be activated after an interruption in operation without additional assistance.

Another object of the invention is to improve a method for operating godets in a textile machine, which is especially adapted to the process flow and its requirements.

According to the invention, this object is achieved with the features of claim 1 for the godet, with the features of claim 10 for the godet control method, and with the features of claim 16 for the godet operating method. features to accomplish this purpose.

Advantageous developments of the invention are defined by the features of the subclaims and combinations thereof.

The invention is based on the discovery that a godet of a textile machine, which is used to guide the yarn, has a godet shell with a relatively low mass, which has a relatively low mass moment of inertia. In this respect, the manually generated rotational movement of the godet housing of such a godet can be carried out by the operator without any assistance. Since the operator usually picks up the yarn manually again via the suction gun after an interruption in operation and causes the yarn to protrude from the front of the godet housing, a manual rotational movement can be imparted to the godet housing by the operator's hand. A manually generated rotational movement of the godet housing is transmitted into the electric drive and can be detected and used for an appropriate restart. In this respect, no additional switching mechanism is required to carry out the actuation of the drive.

In order to generate a measurable signal directly in the electric drive due to the rotation of the godet housing, the godet according to the invention is preferably designed in such a way that the electric drive is formed as a brushless synchronous motor with integrated control electronics, wherein The godet housing is firmly connected to the motor shaft of the synchronous motor. Thus, as the godet housing rotates, the motor shaft in the synchronous motor is moved. Thus, an electrically usable signal can be generated directly via the magnetic coupling between the stator and the rotor within the synchronous motor.

An induced voltage or an induced motor current can be used as a measurable signal. In this respect, the development of the invention is advantageous in that the control electronics has a voltmeter for measuring the induced voltage and an evaluation unit for generating the activation signal. Alternatively, the control electronics is designed with an ammeter for measuring the motor current, wherein the evaluation unit generates a suitable start signal from the measured current value.

However, during the operation of the godet, in particular when removing undesired yarn loops on the peripheral surface of the godet housing, unexpected rotations of the godet housing occur. In order not to achieve a premature restart of the electric drive in the event of such an undesired godet housing rotation, the following godet development according to the invention is preferably realized, in which the evaluation unit has a differential operator for determining the synchronous motor The angular acceleration of the motor shaft. Therefore, the rate of increase of the current change or voltage change is proportional to the angular acceleration of the motor shaft. A restart should be performed as soon as the angular acceleration of the motor shaft is high enough.

The evaluation unit therefore has a comparator for comparing the actual value of the angular acceleration with a stored threshold value. As a result, the generation of signals in the electric drive due to undesired rotation of the godet housing can be eliminated.

In order to prevent the electric drive from being overloaded during godet operation, the following development of the invention is provided, wherein the godet housing is closely associated with a friction mechanism, which has a friction surface that can be opposed to the godet, and the electric The drive unit has a running torque monitoring function. If yarn loops form on the circumference of the godet housing, there may be a sudden increase in the operating torque of the electric drive, so that a quick shutdown is possible to avoid overloading.

In order to increase the yarn tension, the yarn is preferably guided in multiple turns around the circumference of the godet housing. For this purpose, the following development of the godet according to the invention is provided, in which the godet housing cooperates with a rotatably mounted roller in order to guide the yarn in multiple turns.

It is also common in textile machines that a number of workstations are arranged next to each other and thus a plurality of godets are controlled in parallel joint groups at the start and end of the process. In this regard, it is advantageous to assign a manual switch to the drive to activate and deactivate the godet housing.

In principle, the godet according to the invention is also suitable for guiding a plurality of threads simultaneously on the circumference of the godet housing. It is important here that the godet housing connected to the electric drive can be manually set in rotation.

The godet control method according to the invention is characterized in that it is not necessary to bypass the switching control of the starting drive. Instead, the drive of the godet housing can be restarted directly by a manually generated rotational movement of the godet housing.

To enable the starting operation so that it can be automated without additional assistance, the godet housing is driven by the motor shaft of a brushless synchronous motor with integrated control electronics. Such BLDC motors are particularly suitable for being able to implement control algorithms directly on the drive.

Thus, the current or voltage of the synchronous motor can be measured during the rotational movement of the motor shaft, and the start signal can be generated from the measured value directly in the control electronics.

In particular, in order to be able to rule out undesired godet housing rotations that may occur, for example, when the operator unwinds the yarn, it is advantageous to measure the current of the synchronous motor over time during the rotational movement of the motor shaft for restarting. The increase and/or the voltage is increased over time in order to subsequently generate an activation signal from the measured value in the control electronics.

It has been shown that the rate of increase in current or voltage induced by manually generated rotational motion is proportional to the angular velocity of the motor shaft. In this regard, by using the rate of increase of the current change or the voltage change, the angular acceleration of the motor shaft can be determined, which can lead to an activation signal based on a comparison between the actual value of the angular acceleration and a threshold value.

The control of the godet can be further improved by continuously monitoring the operating torque of the electric drive, in particular with regard to switching off the drive. As a result, the drive can be switched off without further assistance when a predetermined operating torque limit is exceeded.

The method according to the invention for operating the godet in a textile machine is characterized in that all actions to be carried out on the godet after a yarn interruption involve directly the godet housing. For example, it is necessary to make the yarn fall on the peripheral surface of the godet shell and restart the godet shell. Thus, all important actions can be performed by the operator directly on the godet housing. To restart the drive, the operator performs a rotational movement of the godet housing by hand. For this purpose, the godet housing can be turned by a quick hand movement in the direction of rotation of the godet housing. During the rotation, the godet housing performs successive multi-turns. Here, the operator preferably places his hand flat on the peripheral surface of the godet housing with a certain force, in order to then accelerate the godet housing with a rapid lateral movement of the hand in the direction of rotation.

This rotational movement can preferably be generated in the direction of rotation of the electric motor and in a direction opposite to the direction of rotation of the electric motor, the godet housing being driven by a brushless synchronous electric motor with integrated control electronics. For signal generation, the direction of rotation of the motor shaft for signal induction is not important.

In order to be able to start and end the working process, in particular in the case of several godets, regardless of the respective operating state, the drive is activated and deactivated via a switch to be activated manually. Such switches can be implemented as grouped switches for controlling a plurality of godets, or as individual switches for controlling individual godets.

The present invention will be described in detail below with reference to the accompanying drawings using some embodiments of the device of the present invention, wherein:

Figure 1 schematically shows a cross-sectional view of an embodiment of a godet according to the invention,

Figure 2 schematically shows a side view of the embodiment of Figure 1 in different operating situations in a textile machine,

FIG. 3 schematically shows a flow chart involving the generation of an activation signal for an electric drive,

FIG. 4 schematically shows the temporal curve of the measurement signal from the electric drive during a manually generated rotational movement,

Fig. 5 schematically shows a side view of another embodiment of a godet according to the invention.

An embodiment of a godet according to the invention is shown in cross-sectional view in FIG. 1 . The godet has a pot-shaped godet housing 1 which is fixed in a non-rotatable manner to the protruding free end of a motor shaft 3 of an electric drive 2 . The electric drive 2 in the present embodiment is formed in the form of a brushless synchronous motor 4, which is also called a BLDC motor. The electric drive 2 thus comprises a synchronous electric motor 4 and integrated control electronics 5 .

The electric drive device 2 and the godet housing 1 are realized in the form of a structural unit, and the electric drive device 2 has a housing composed of several parts. Accordingly, the motor shaft 3 of the synchronous motor 2 is rotatably mounted in the bearing housing 8 via a plurality of rolling bearings 9 . The motor shaft 3 has an end opposite the godet housing 1 , on which end the rotor 10 is arranged. The rotor 10 is formed by permanent magnets not specifically described here. The rotor 10 is surrounded by a stator 11 on which a number of windings are mounted. The stator 11 is held by a motor mount 12 . The motor mount 12 extends between the bearing housing 8 and an electrical housing 13 which is arranged directly on the synchronous motor 4 . Control electronics 5 are accommodated in the electrical housing 13 . The electrical housing 13 and the bearing housing 8 are connected to each other via a plurality of fastening bars 31 .

The control electronics 5 in this embodiment are symbolically represented by a circuit board 14 and a power module 15 , an inverter 17 and an evaluation unit 19 . In particular the control electronics 5 has a measuring device 16 which is usually coupled to the evaluation unit 9 . A storage means 18 which is usually integrated in the evaluation unit 19 is also provided. The memory means 18 and the evaluation unit 19 can then be formed in the form of a microprocessor.

Control electronics 5 is connected via supply lines 21 to a voltage source 21 , not shown here. A further connection to the control electronics 5 is represented by a data line 20 which allows data exchange with a superordinate machine control unit 22 . Furthermore, in this embodiment the control electronics 5 are directly connected to the switch 23 in order to be able to carry out the activation of the electric drive 2 at the beginning of the working process or at the end of the working process.

The function of the godet shown in Figure 1 will be explained below with reference to the other Figures 2.1, 2.2 and 2.3. Figures 2.1, 2.2 and 2.3 each show a view of the embodiment of Figure 1 when used in a textile machine. Figure 2.1 shows the godet cooperating with the yarn guide, Figure 2.2 shows the godet in operation when forming a yarn coil, and Figure 2.3 shows the godet when the electric drive 2 is restarted.

Inside the textile machine, the godet according to FIG. 1 is held by a support 27 . Here, the godet housing 1 is held in position on the front side of the support 27 and the electric drive 2 is held in position on the rear side of the support 27 . On the front side of the support 27 , a rotatably mounted roller 28 is assigned at a distance to the godet housing 1 . In addition, a friction mechanism 24 is fixed on the front face of the support 27 , which friction mechanism is kept at a relatively short distance from the godet housing 1 with the friction surface 26 . In this embodiment, the friction mechanism 24 is formed by a pin 25 fixed to an abutment 27 , oriented coaxially with respect to the godet housing 1 and extending substantially over the entire length of the godet housing 1 .

FIG. 2.1 shows the situation in which the yarn 29 is guided over the circumference of the godet housing 1 and the circumference of the roller 28 in a multi-winding manner. The godet housing 1 in this operating state is driven by the synchronous motor 4 at an essentially constant rotational speed. The synchronous motor 4 is controlled via control electronics 5 whose rotational speed setpoint is entered via a data input mechanism.

In the case of yarn coils formed on the peripheral surface of the godet housing 1 due to yarn breakage before or after the godet or sagging before or after the godet, the effect of the yarn on the godet housing 1 Each changing pulling action results in a change in the operating torque of the synchronous motor 4 . FIG. 2.2 shows this situation, where the yarn winding 30 on the peripheral surface of the godet housing 1 is started by winding the incoming yarn 29 . However, the yarn loop 30 can also occur due to the yarn that has left, as a result of which the returned yarn is guided to the yarn loop 30 .

Regardless of the manner in which the yarn coils 30 appear on the peripheral surface of the godet housing 1, each change in the actual value of the running torque is measured in the control electronics 5 and compared with the stored limit value of the running torque of the synchronous motor 4 Compared. As soon as the yarn wrap 30 comes into contact with the friction means 24 , an additional operating torque is generated via the friction surface 26 and leads to a very rapid increase in the operating torque of the synchronous motor 4 . As soon as an impermissible increase in operating torque is detected, a switching signal for switching off the synchronous motor 4 is generated in the evaluation unit 19 of the control electronics 5 . The motor shaft 3 together with the godet housing 1 is stopped so that the operator can remove the yarn wrap 30 on the peripheral surface of the godet housing 1 .

Figure 2.3 shows the situation just before the end of the outage. In this case, the operator introduces the yarn 29 into the artificial jet 32 for doffing on the circumference of the godet housing 1 . Here, the godet housing 1 was previously set in rotation by manual movement by the operator. To this end, the peripheral surface of the godet housing 1 is touched by hand, so that the operator can realize an accelerated initial rotation of the godet housing 1 through a manual movement generated rapidly in the direction of rotation. The godet housing 1 rotates with the motor shaft 3 so that a signal is induced via the rotor 10 in the synchronous motor 4 .

In order to further explain the start-up operation of the electric drive device 2 , refer to FIG. 3 . The flow chart relating to the generation of the starting signal for the synchronous motor 4 is shown schematically in FIG. 3 .

Since the motor shaft 3 rotates, induction of motor current and voltage occurs in the synchronous motor 4 . As can be seen from FIG. 1 , the control electronics 5 has a measuring device 16 which can be realized in the form of an ammeter or a voltmeter. In this connection, the induced voltage U or the induced motor current I induced by the manually generated rotational movement of the godet housing and the motor shaft 3 is measured by means of the measuring device 16 . The measured values of the induced voltage or the induced motor current are supplied to an evaluation unit 19 of the control electronics 5 .

The magnitude of said signal and thus the absolute value of the induced voltage and/or the induced motor current cannot be unambiguously evaluated to unambiguously associate the induced signal originating from the rotational movement of the motor shaft with the manual generation process. For example, when eliminating yarn loops on the peripheral surface of the godet housing 1, a rotational movement of the motor shaft can likewise be produced, inducing a current or a voltage. In order to distinguish rotational movements, the measured signal is differentiated. For this purpose, the evaluation unit has a differential operator 33 which measures the rate of increase of the induced voltage and/or the induced motor current. This rate of increase is indicated in FIG. 3 by the ratio d/dt. This rate of increase is proportional to the angular velocity of the motor shaft 3 . Differentiating the measured signal then leads to a criterion for the angular acceleration a.

The angular acceleration required to start the operation of the synchronous motor 4 is stored as a threshold a _s . For example such a threshold value can preferably be stored in the memory device 18 of the control electronics. In order to carry out the comparison between the actual state and the threshold value, the evaluation unit has a comparator 34 which compares the determined angular acceleration with the angular acceleration threshold value. In the event of an angular acceleration threshold value being exceeded, a control signal for starting synchronous motor 4 is generated by evaluation unit 19 . Evaluation unit 19 outputs suitable signals to inverter 17 for this purpose. For the case that the angular acceleration threshold is not exceeded, the evaluation unit 19 will not trigger any start function.

The flow chart shown in FIG. 3 involving the generation of the activation signal is exemplary. In principle, however, it is also possible to generate the activation signal directly from the induction signal. FIG. 4 therefore shows a schematic example of the time profile of the induced motor current. In this graph, the time t is plotted on the horizontal axis and the motor current I is plotted on the vertical axis. The graph in FIG. 4 shows two curves, which are labeled I ₁ and I ₂ . The motor current I ₁ has been measured at the synchronous motor 4 , for example, during a rotational movement of the godet housing manually produced by an operator. The limit curve with the designation _I2 represents, for example, an undesired rotational movement of the godet housing during the elimination of yarn loops. The curves of the induced motor currents I ₁ , I ₂ are distinct with a slope which can be seen, for example, from the time difference t ₁ -t ₂ . At time t ₁ , current values I ₁ and I ₂ are measured, the measured value I ₁ being greater than the measured value I ₂ . In a corresponding manner, at time t ₂ the current values I ₁ ′ and I ₂ ′ are measured. For the purpose of differentiation, the measured value changes that occur as a function of the time difference are then recorded and evaluated. The measured value changes I ₁ ′–I ₁ and I ₂ ′–I ₂ occurring within the time period t ₁ -t ₂ represent the magnitude of the rate of change of the current value. Then, by comparing the actual value with a threshold value not previously entered here, each rotational movement that occurs on the godet housing can be detected and used to restart the electric drive.

Figure 5 illustrates another embodiment of the godet of the invention as it is used in a textile machine. The exemplary embodiment in FIG. 5 shows a total of four godets, which are mounted on a common support 27 . The support 27 holds a plurality of godet shells 1 on the front side and a plurality of rollers 28 held on the support 27 in a freely rotatable and cantilevered manner. The godet housings 1 are each connected via a motor shaft 3 to an electric drive 2 arranged on the rear side of a support 27 . In this exemplary embodiment, a total of four electric drives 2 are arranged next to each other. The number of drives 2 and the number of godet housings on the support 27 are exemplary. In principle, eight, twelve or sixteen or more godets can be arranged on the godet support.

The godet held on the support 27 is realized as in the exemplary embodiment according to FIG. 1 . In the exemplary embodiment shown in FIG. 5 , the power supply to the electric drive 2 is provided via a power supply line 21 , which is connected via a group control unit 35 and a group switch 36 to a superordinate power supply unit not specifically shown here. The drive device 2 is connected to the group control unit 35 via a data line 20, which is preferably realized in the form of a BUS system. The group control unit is connected to the machine control unit 22 .

Predetermined operating parameters for the operation of the associated godets are stored in the group control unit 35, each electric drive 2 being individually addressable and actuatable.

In this embodiment, each motorized drive 2 can be provided with an independent switch 23 in order to be able to stop the godet housing, for example, during a product change. The switch 23 is shown in dashed lines in FIG. 5 . In the event that a yarn winding and thus an interruption of operation is required on one of the godet housings 1 , the operation and control of the godet is carried out according to the above-described embodiment of FIGS. 1 and 2 . In this regard, reference is made to the above description.

The godet according to the invention and the godet control method according to the invention as well as the godet operating method according to the invention are particularly suitable for obtaining a fast and reliable control of the operating process at many work stations in a textile machine. Complicated wiring can be avoided here due to the use of brushless synchronous motors with integrated control electronics. In addition, fast reaction times under changing operating conditions can be achieved.

Claims (18)

1. the draw-off godet being used for guiding yarn, this draw-off godet has the draw-off godet shell (1) that can be driven and be connected to Vidacare corp (2), it is characterized in that, this Vidacare corp (2) is so designed that, that is, be in operation the have no progeny rotational motion of the described draw-off godet shell (1) that can manually produce of described Vidacare corp (2) is restarted.

2. draw-off godet according to claim 1, it is characterized in that, described Vidacare corp (2) is formed by the brushless synchronous motor (4) with integrated control electronic installation (5), and wherein said draw-off godet shell (1) is firmly connected to the motor reel (3) of described synchronous motor (4).

3. draw-off godet according to claim 2, it is characterized in that, described control electronic installation (5) has the voltameter (16) for measuring induced potential (U) and for producing the assessment unit (19) of enabling signal.

4. draw-off godet according to claim 2, it is characterized in that, described control electronic installation (5) has the galvanometer (16) for measuring motor current (I) and for producing the assessment unit (19) of enabling signal.

5. the draw-off godet according to claim 3 or 4, it is characterized in that, described assessment unit (19) has the differentiation operator (33) of the angular acceleration (a) of the motor reel (3) for determining described synchronous motor (4).

6. draw-off godet according to claim 5, is characterized in that, described assessment unit (19) has the actual value for relatively described angular acceleration (a) and stored threshold value (a_s) comparator (34).

7. draw-off godet according to any one of claim 1 to 6, it is characterized in that, described draw-off godet shell (1) is closely equipped with friction mechanism (24), this friction mechanism has the friction surface (26) opposed with described draw-off godet shell, and described Vidacare corp (2) has operating moment supervising device (16,19).

8. draw-off godet according to any one of claim 1 to 7, is characterized in that, described draw-off godet shell (1) is cooperated to guide yarn (29) in the way of being repeatedly wound around with the roller (28) installed in a rotatable manner.

9. draw-off godet according to any one of claim 1 to 8, is characterized in that, described Vidacare corp (2) is equipped with hand switch (23), is used for starting and close down described draw-off godet shell (1).

10. a draw-off godet control method, the draw-off godet shell of wherein said draw-off godet is driven by Vidacare corp, it is characterized in that, is in operation and has no progeny, and the rotational motion of the described draw-off godet shell that described Vidacare corp manually produces is restarted.

11. method according to claim 9, it is characterized in that, described draw-off godet shell is driven by having the motor reel of the integrated brushless synchronous motor controlling electronic installation.

12. method according to claim 10, it is characterized in that, the electric current of described synchronous motor and/or voltage are measured in the rotational motion process of described motor reel, and produce enabling signal from measured value in described control electronic installation.

13. method according to claim 10, it is characterized in that, in described motor reel rotational motion process, the electric current of described synchronous motor increase over and/or voltage increase over measured, and in described control electronic installation from measured value produce enabling signal.

14. the method according to claim 11 or 12, it is characterized in that, the angular acceleration of described motor reel is determined, and described enabling signal produces according to the comparative result between actual value and the threshold value of described angular acceleration.

15. the method according to any one of claim 10 to 14, it is characterized in that, the operating moment of described Vidacare corp is continually monitored.

16. the method running draw-off godet in weaving loom, wherein, in running status, described draw-off godet shell is actuated to guide yarn by Vidacare corp, it is characterized in that, being in operation and have no progeny, the rotational motion of the described Vidacare corp draw-off godet shell by manually being produced by operator is restarted.

17. method according to claim 14, it is characterized in that, described draw-off godet shell is driven by having the integrated brushless synchronous motor controlling electronic installation, and the rotational motion of the draw-off godet shell for restarting synchronous motor manually produced or in opposite direction with motor rotation carries out on motor rotation direction.

18. the method according to claims 14 or 15, it is characterized in that, when the packet circuit of multiple driving devices of multiple draw-off godet shells, described Vidacare corp is activated by switch to be manually booted and is closed down.