JP6510059B2 - Starting method of loom - Google Patents

Description

  The present invention relates to a method for the controlled starting or operation of a weaving machine and an opening device, the weaving machine being driven by a main drive and the opening device being driven by an electric motor assisted drive.

  Such weaving machines and opening devices are known. In these, the opening device comprises a separate drive whose central drive shaft is connected to the electric motor, from which the movement of the opening means is induced. In this regard, the opening device can be separated from the movement of the central drive shaft, such as the Staubli type 2881 dobby machine, or the Staeubli type LX jacquard machine, or the Bonas SI .

  The drive shaft of the weaving machine, from which further movement (the weaving machine, if applicable mechanical weft insertion element) is induced, is then connected to at least one actuator which drives it directly, The actuator is likewise usually realized as an electric motor. Such direct drive has a very simple mechanical structure, requires almost no maintenance, and can be adjusted very accurately.

  Furthermore, the drive of the weaving machine and the drive of the opening device are connected by a common DC voltage intermediate circuit (hereinafter referred to as a converter intermediate circuit), thereby forming or generating an energy flow together. Can.

  One of the disadvantages of the above-described direct drive of the loom is that the high peak power required for the required highly dynamic loom start-up must be supplied directly via the actuator. This peak power should essentially be supplied directly by the power supply network. Such power peaks lead to strong voltage drops even in the case of stable power supply networks and appropriate power supply conductor cross sections, which further develop into the intermediate circuit voltage of the converter used for direct drive, Interruptions and stops of the loom start can be falsely triggered. This problem is even more pronounced if the loom operates on a weak power supply network. The shift in textile production to developing and emerging countries is on the rise. If a reserve transformer is required because of the rated voltage level and / or type of the power supply network, the condition becomes further disadvantageous, whereby the reserve transformer should be started because of the additional characteristic impedance. Further weakening the power supply network from the perspective of the weaving machine.

  If it is not possible for the loom to start up to the rotational speed provided for the first beating (hereinafter referred to as the operating rotational speed) for the above reasons, measures are known to reduce this rotational speed . That is, the operating rotational speed for the first strike may be significantly different than the operating rotational speed actually provided to the article. However, this can cause the fabric to have a start mark and an unacceptable loss of quality. Likewise, a general reduction in the operating speed is not an acceptable solution, because there is a problem with the economic profitability of the weaving mill, as production of the product takes correspondingly longer. .

  German Utility Model No. 20021049 shows, as the closest prior art, the possibility for separate drives for looms and opening devices, which is known from DE 100 530 079. The preferred start-up process of the opening device is adapted to support the subsequent start-up process of the loom having kinetic energy. To that end, the opening device is accelerated to a rotational speed which exceeds the operating rotational speed to be reached at the end of the start of the loom. Thereafter, during the start of the loom, i.e. during the start-up phase, the opening device releases kinetic energy by re-braking to assist the start of the loom.

  German Utility Model DE 200 21 049 focuses, inter alia, on the drive solution having a common motorized element for textiles and opening devices, so that the braking process of the opening devices is: It is proposed to start at the beginning of the loom start-up and proceed (substantially) uniformly during this start-up process. However, at the beginning of the loom start-up such feedback has proved to be suboptimal, as the opening device will feedback more energy than required by the loom. The voltage level of the common converter intermediate circuit of the loom and the drive of the opening device then rises sharply and its energy has to be converted into heat of the braking resistor, which will be lost for the process.

German Utility Model No. 20021049 specification German Patent No. 10053079

  Therefore, the object of the present invention is to reduce the peak power requirement of the loom by making better use of the kinetic feedback energy of the opening device, thereby maintaining the voltage limit in the converter intermediate circuit. Ensure safety. It should also be tolerated if there is no reduction of the starting motive force of the loom.

  This object is achieved in the method according to the invention by the features of the independent claims. According to the invention, the method for starting or operating comprises on the one hand starting or operating the opening device to a predetermined overspeed or overspeed (hereinafter referred to as step 1) and on the other hand the starting phase Setting the adjustment of the reduction in the rotational speed of the opening device so that the gradient of the rotational speed curve or the progression of the opening device becomes smaller in a section after the previous section (hereinafter referred to as step 2).

  In step 1 described above, the overspeed at which the opening device is accelerated with respect to the operating rotational speed at the first tapping is predetermined, so that its value and / or its upper limit is precisely defined. The overspeed is particularly preferably calculated automatically at least on the basis of the machine data, but is preferably also calculated on the basis of the process data. This is described in more detail below.

  Step 2 provides a non-slope path progression or curve, thus a non-constant slope to the rotational speed of the opening device starting from the overspeed from step 1 during the time range t1 to t3; Preferably, the start-up process from t2 to t3 of the weaving machine can be completely included in time or matched with it in time. The progression of the gradient, ie the curve, is such that energy feedback is greater in the time interval after the start-up process than in the previous time interval. This means that the braking of the opening device does not proceed in a uniform manner (in the form of a ramp) during start-up of the loom, but rather in the section after the start-up phase, preferably towards the end of start-up of the loom It means to become strong. Thus, taking into account heat and other losses, the actual energy requirements of the loom are taken into account.

  Thus, according to the invention, the feedback of energy or power proceeds in a manner which meets the demand or demand, ie to a particularly strong extent when the demand or demand by the starting loom is strongest.

Preferably, in time averaging , the rotational speed progression of the aperture device between times t2 and t ', ie the slope of the curve, is not smaller than the time average between times t' and t3. Thus, the slope of the rotational speed curve of the opening device towards the end of the start phase is smaller than the earlier time period of the start phase. This means that at the end of the start-up phase more energy is fed back from the opening device to the loom than at the beginning of the start-up phase.

The same advantageous rotational speed curve, the temporal average time t2 and the time point t 'gradient of the rotational speed curve of the opening device between the time point t' absolute value of the temporal average of between times t3 and Contains an absolute value smaller than

  It is particularly preferred that the slope of the rotational speed curve of the opening device towards the end of the starting phase is the smallest of the total time periods of the starting phase. Thus, in this embodiment, the energy feedback is maximum at the end of the loom start at time t3.

  If the slope of the rotational speed curve of the shedding device starting at the instant t1 or t2 is a decreasing function which gradually decreases monotonously, the energy supply from the shedding device to the weaving machine rises continuously, which means that It reflects the actual energy demand or demand relatively accurately.

  Also, in a preferred embodiment, the rotational speed curve of the starting loom is not ramp-shaped, but is defined such that the slope decreases over the entire starting process (between times t2 and t3) or at least towards the end thereof Be done. This equalizes the power take-up, i.e. the power peaks at the end of the loom start-up are not so pronounced, which facilitates the energetic start-up assistance by the opening device. In this regard, it should be noted that the rotational speed of the loom should at present be understood as a value calculated and determined from its kinetic energy and energy average mass moment of inertia (defined below).

  As mentioned above, the overspeed or overspeed of a given opening device is preferably calculated by a computing device using machine data. Likewise, the rotational speed curve of the opening device for the entire start-up phase of the weaving machine is calculated by the computing device using machine data, for which the rotational speed curve of the opening device is preferably calculated as expected. Meet the power demand or demand of the loom.

  The predetermined mechanical data preferably comprises: mass moment of inertia of the opening device and / or the weaving machine, energy average mass moment of inertia of the opening device and / or the weaving machine, network and power supply related data, eg characteristic data of a common converter intermediate circuit or It is a part or all of data selected from the technical characteristic data of the driving device of the opening device and the loom, the peak power of the power source and the like.

  Not only machine data, but also process data are preferably used to increase the accuracy of the calculation of the overspeed and further rotational speed curves of the opening device. These process data which are preferably at least partially utilized are preferably based on the calculated or estimated loom losses, preferably also on the loss of the opening device. Also preferably, these process data include such data based on the duration of the predetermined start-up phase of the loom.

  Both step 1 and step 2 will be described in more detail below.

  For step 1, overspeed of the opening device is calculated. Preferably, at least the energy average mass moment of inertia of the weaving machine and the opening device is used as machine data. In this regard, the energy average mass moment of inertia is the mass moment of inertia of a virtual flywheel mass rotating at the same operating rotational speed as the work machine (woven machine or opening device) and has the same kinetic energy as a suitable work machine.

  By means of the relationship or ratio of these two energy average mass moments of inertia of the weaving machine and the opening device, the relationship or ratio of the two relevant kinetic energies is also fixed with the same magnitude as at the end of the start-up or run. It is possible (by calculation) to accelerate the opening device to such an increased overspeed, so that a great deal of energy is released during subsequent re-braking so that it is sufficient for starting the loom. In this regard, a calculation example of a lossless system is:

Regarding looms:
Energy average mass moment of inertia: J _WM = ² kgm ²
Operating rotational speed at the end of start: ω _Arb = 600 min ^-1
The kinetic energy is then:
W _{kin, WM} = 2J _WM x ω _Arb ² = 3948 J
It becomes.

Regarding the opening device:
Energy average mass moment of inertia: J _FBM = 4 kgm ²
Operating rotational speed at the end of start: ω _Arb = 600 min ^-1
The kinetic energy is then:
W _{kin, FBM} = ² J _FBM × ω _Arb ² = 7896 J
It becomes.

In order to be able to completely cover the energy requirements of the loom, the opening device needs to have a kinetic energy of (7896 + 3948) J = 1844 J at the beginning of loom start-up, which corresponds to a rotational speed of 735 min- ¹ . However, the large size of the opening drive is not desirable for cost reasons, so the above proposal for extracting the energy requirements for starting the loom completely from the opening device is not practical. However, the example calculation shows that the energy average mass moment of inertia is a sensitive value for determining the rotational speed profile or movement path of the shedding device during start-up of the loom.

  Further important values are given by the network and power supply conditions already mentioned above. In this context, in particular, characteristic data of the power supply for the common converter intermediate circuit of the weaving machine and the shedding device are taken into account in particular.

  Furthermore, it is preferred to take into account the peak power of the power supply, for example a multiple of twice the rated power applied during the start-up duration of the loom. For example, due to the special network, eg IT network, it is equally important whether the spare transformer is used in the weaving shop. In this regard, the power and short circuit voltage or internal impedance of the preamp play an important role. The network and power supply conditions mentioned in the above range and context, as well as the technical characteristic data of the drive of the weaving machine and the shedding device, are assigned to the machine data, which data, for example, peak current of the regulator or controller and / or Or includes the peak rotational moment or torque of the actuator or motor.

  Among other things, the expected loss of the loom during the start-up process relates to process data. These can be estimated, for example, from the temperature of the transfer oil, or, if the machine is already operating, the average consumption current taking into account the stopping time which has stopped, or again the temperature of the oil, if applicable, It can be estimated from the new operating rotational speed. It is preferable to also consider the losses of the opening device including the opening means (holding frame, lift wire).

  Average power and peak power can be calculated from the total energy demand or demand of the loom in the start-up process (sum of kinetic energy at operating rotational speed and compensation for losses) and from the start-up period. It is then possible to estimate from the network and power supply conditions whether starting assistance with the opening device is necessary or whether it should be used for this power (especially peak power).

  Correspondingly, according to a preferred embodiment, the overspeed of the opening device at the beginning of the start of the loom is determined by the energy average mass moment of inertia of the opening device, and the required energy or power is again taken to the operating rotational speed It can be provided by braking. If this is done on the basis of uniform ramp shape rebraking of the opening device over time, in this way the overspeed of the opening device gets the smallest possible value acceptable for energy feedback. become.

  By means of the above method it is possible, for the purpose of assisting the start of the weaving machine, to generate mathematically defined definitions or pre-definitions of the rotational speed behavior of the opening device simply through the use of step 1. However, within the scope of the present invention, as already mentioned above, it has been recognized that braking of the uniform, i.e. ramp-shaped, opening device during start-up of the weaving machine is not optimal. In this case, i.e. at the beginning of the loom start-up, the opening device will feed back much more energy than the loom requires. This can cause false triggers of interruption and shutdown of the start-up process very quickly, due to the unacceptably high voltage of the converter intermediate circuit, especially the passive network power supply.

  According to the invention, this problem is solved through the use of step 2. Due to the smaller gradient of the speed of the opening device during the start-up phase of the loom during the start-up phase of the loom, little or no energy is initially supplied to the converter intermediate circuit and, depending on the passage of time, the power from the loom Or energy demand increases.

  Prior to carrying out steps 1 and 2 above, whether or not further energy based start-up assistance by the opening device is required by the predetermined computing device, preferably based on the machine data and, if applicable, the process data It is determined. If start-up assistance is required, the operator is preferably asked to activate or authorize this start-up assistance or be notified that it has been activated automatically. However, in the latter case, it is recommended that the operator be able to stop the starting assistance again.

  The invention is described below in connection with an exemplary embodiment.

It is a flowchart for demonstrating the calculation method of the feedback in the case of a fixed energy transfer part. In order to clarify the present invention, it is a rough rotational speed-time diagram for t1 <t2. FIG. 3 is a schematic rotational speed-time diagram in which t1 <t2 as in FIG. It is a rough rotational speed-time diagram in the case of t1> t2.

  FIG. 1 shows a calculation method which proceeds from the starting point and proportionally supports the power demand of the loom at each start of the loom, and the ratio is relatively constant (eg 40%) It remains. Starting of the weaving machine must proceed so that the rotational speed calculated from the kinetic energy and energy average mass moment of inertia increases to the ramp shape over time to the operating rotational speed. Thus, in this regard, the expected power demand of the loom remains constant with respect to the time t2 which is not located before the time t1 when the opening device has reached the predetermined overspeed, ie the percentage possible at the start of the loom Covered in proportions.

  In the calculation step 1A, the initial maximum power demand or demand of the loom is determined from the machine data and process data 1A '. In this example, the operating rotational speed of the loom and the energy average mass moment of inertia are used as machine data. The expected loss or loss moment and start-up period of the loom, represented as time or transition angle range, is included as process data.

  Preferably, the kinetic energy of the loom is first calculated towards the end of the start-up process and thus at the operating rotational speed. The energy divided by the transition angle range gives a mechanically effective acceleration moment. To this is added the expected loss moment at the operating rotational speed, which depends mainly on the oil temperature in the transmission. The resulting total moment multiplied by the operating rotational speed provides the maximum power requirement of the loom.

  This maximum power requirement is compared to the machine data characterizing the network or power supply condition, which is characteristic of the power supply unit for the converter intermediate circuit (passive or active network power supply, if applicable, boost function or boost converter) Not only the function, peak power) but also the characteristic data (rated power, short circuit voltage or internal impedance) of the potential backup transformer are included. The comparison is an estimate. For example, at which peak power a suitable spare transformer or a suitable power supply unit is expected to show what voltage drop it is stored in the table. If the total voltage drop in the converter intermediate circuit thus expected is very strong or significant, then the voltage demand at the motor terminals can no longer be fulfilled and / or the undervoltage of the converter intermediate circuit The detector is triggered causing interruptions and stops of the start-up process, and correspondingly, parts of the opening device have to be supplied with additional energy or power. The proportion of this power supplied from the opening device is output from the calculation step 1A as the value 1a '(demand quantity).

  It is suitable for this purpose that the known peak torque or rotational moment of the aperture drive be multiplied by its operating rotational speed in the calculation step 1B if the calculation step 1B is carried out simultaneously or in parallel with the calculation step 1A. . Peak power of the aperture driver can be obtained. Where applicable, the loss moment has been previously subtracted from the peak torque. The peak power of the aperture driver calculated in this way is output as the value 1b '(capacity or possibility) from the calculation step 1B.

  In calculation step 2, first, 1a '(demand volume or demand volume) and 1b' (capacity or possibility) are compared. If the demand quantity is greater than the capacity, it is not possible to eliminate the above-mentioned type of problems during start up to the intended operating speed. Thus, the reaction is triggered in step 2B. This may consist of a warning signal to the operator (see path 2b '), if appropriate, selecting a lower operating rotational speed and associating it with a request to start the machine in the test method. In this way, the estimate from step 1A can be corrected by the actually observed behavior of the converter intermediate circuit. Another possibility involves automatically reducing the operating rotational speed under corresponding information notification to the operator. Again, proper machine start-up can serve for verification and, if applicable, for correction of the hypothesis from step 1A. In this regard, the reduced operating rotational speed should be calculated such that the demand 1a 'is exactly the same as the capacity 1b'.

The smaller of the two values 1a ′, 1b ′ mathematically represented as Min (1a ′, 1b ′) is transferred to calculation step 3 as 2c ′. Half of this peak power multiplied by the time required to start the loom gives the energy to be replenished to the part of the shedding device, which energy must be available at the start time t2 of the loom. The calculation from this auxiliary energy of the opening device, the operating rotational speed and the energy average mass moment of inertia, at the instant t2, the overspeed ω _{U, FBM} which the opening device must have in comparison with the operating rotational speed give. (See also the lossless system calculation example above for further understanding.)

The power demand or demand of the loom during start-up occurs in proportion to the rotational speed and time, correspondingly the power is supplied to the part of the opening device according to the above arrangement or agreement for this method (Until finally the value 2c 'is reached). From this fact and the values of ω _{U and FBM} (t 2) already known, it is possible to calculate the value ω _FBM (t) of the rotational speed of the opening device at any desired time t until the start-up time t 3 of the weaving machine it can. Integration of time yields the progression of the angle or curve φ _FBM (t). Depending on how the drive regulator or controller needs a given instruction, for example [t2. . . For equidistant time points in the range of t 3], the associated ordinate values of ω _FBM (t) or ω _FBM (t) are used to form pairs of values (supporting points), whereby the software routine If applicable, the drive regulator or controller itself generates the corresponding formula for the electronic cam disc. Further transmission of the data required for the calculation from the weaving machine is referred to 1a ′ ′ in FIG.

  A different preferred calculation method is to use polynomials, the coefficients of which are determined in such a way that the rotational speed or angular progression of the aperture device is predetermined relative to the start-up range of the loom in the desired manner.

Three exemplary progressions or curves of the rotational speed of the opening device (FBM) and the weaving machine (WM) as a function of time corresponding to the invention are shown in FIG. The opening device is started at time t0 and is driven or operated by the time t1 to a predetermined, particularly calculated overspeed ω _{U, F B M} (see above). At time t2, the loom is started, and in the start-up phase from time t2 to time t3, it is raised to the operating rotational speed ω _arb . During this start-up phase, energy is supplied from the opening device to the loom in a defined manner, the possible calculation methods associated therewith being indicated above.

  It is important to the invention that the slope of the rotational speed curve of the shedding device is smaller in the later sections of the start-up phase of the weaving machine (between t2 and t3) than in the preceding sections. In this regard, later sections need not necessarily be bounded at time t3, and / or previous sections need not necessarily be bounded at time t2 (if t1 is later than t2, t1, see FIG. 4). ) Can compare the gradient progressions in the period between time t2 (t1 if t1 is later than t2) and t3 with each other.

From FIG. 2, in this exemplary embodiment, the slope of the rotational speed curve of the aperture device, shown as a solid line (herein referred to as FBM ′), is based on the entire time span of the starting phase Towards the end, i.e. the curve contains the smallest slope at time t3 in the range between t2 and t3. Preferably, the slope of the rotational speed curve of the aperture device between the instant t2 and the instant t 'marked as an example in FIG. 2 is not smaller than the slope in the temporal average between the instant t' and the instant t3. .

  It is also possible that temporarily the rotational speed progression of the opening device between the instants t2 and t3 has a rising slope, ie a rising slope, at an earlier stage of the start-up phase before the slope becomes smaller again. .

  The rotational speed progression of the loom indicated by the solid line (herein referred to as WM ') is shown in FIG. 2 as rising linearly to the ramp shape as assumed in the above calculation method There is. Another rotational speed progression of the weaving machine (referred to herein as WM &quot;) is shown in dashed lines, and the rotational speed during operation between time points t2 and t3 includes a decreasing rising slope. At such a progression, power take-up is more uniform than linear operation, as the power peaks towards the end of loom start are less pronounced. An exemplary corresponding rotational speed curve of the opening device (herein referred to as FBM &quot;) is likewise indicated by a dashed line. The energy feedback towards the end of the start-up phase of the loom, in particular towards the end of the start-up phase of the loom, ie at time t3, is lower than in the previous case where the rotational speed WM 'of the loom rises to the ramp shape The flatter curve in comparison to the velocity curve FBM 'corresponds there to the flatter loom curve WM' '.

  Furthermore, a third variant is shown in FIG. The rotational speed curve of the weaving machine (herein referred to as WM '' ') comprises an S-shape, which is also repeated in the rotational speed curve of the opening device (herein referred to as FBM' ''). The energy feedback from the opening device to the weaving machine becomes greater after each flatter rotational speed curve adjacent to the instant t2, in particular during the strongest or sharpest rise of the rotational speed of the weaving machine. Toward the end of the start-up phase of the weaving machine, both the rotational speed progression, ie the curves FBM ′ ′ ′ and WM ′ ′ ′, become flat again.

  FIG. 3 shows the case where the maximum value of the rotation speed of the above-mentioned opening device exists. It has to be checked whether this exceeds the maximum permissible rotational speed of the opening device.

  The case where the time point t1 is after the time point t2 is shown in FIG. As explained at the outset, in terms of demand or demand, the loom does not benefit from the support for the part of the opening device at the beginning of the start-up phase, and therefore the loom has its opening device calculated at time t1. Before reaching overspeed, it can already be started (at time t2). It is then important that the energy be ready to be transmitted to the loom at time intervals t1 to t3.

  The activation of the main drive of the weaving machine and the electronic auxiliary drive of the opening device is taken over by the controller of the prior art and is therefore not described in further detail here. The above calculations are performed using a computing device connected to the described controller.

  The invention is not limited to the exemplary embodiments shown and described. Modifications within the scope of the claims are possible as a combination of features, even though they are illustrated and described in the different exemplary embodiments.

Claims (9)

Method for controlled operation of a loom and opening device,
The loom and the opening device are connected to a controller,
The loom is driven by a main drive,
The opening device is driven by an electric motor auxiliary drive,
The loom and the opening device are connected by a common converter intermediate circuit for the energy flow transmitted,
The opening device is started at time t0 and increases to an overspeed above its operating rotational speed up to time t1, which is before time t3;
The loom is started at a point in time t2 after the point in time t0 , and the start-up phase of the loom is in the time interval from the point in time t2 to the point in time t3;
Power transmission (feedback) from the opening device to the loom by the converter intermediate circuit is performed at a predetermined start-up stage,
In the method
The opening device is operated to a predetermined overspeed between the time t0 and the time t1, and
The slope of the rotational speed curve of the opening device being smaller in later sections of the start phase than in the previous sections;
Characterized by how. The pre-Symbol time t2 and the time point t 'average value of the gradient of the rotational speed curve of the opening device between the found the time t' not less than the average value of the slope between the said time t3 and The method according to claim 1, characterized in that. The gradient of the rotational speed curve before Symbol opening device is characterized in that when the end of the start-up phase in the total time in the span of the start-up phase is the smallest, the method according to claim 1 or 2. Method according to claim 1 or 2, characterized in that the slope of the rotational speed curve of the opening device is a strictly monotonically decreasing function from the two time points t1 or t2.   Method according to claim 1 or 2, characterized in that the predetermined overspeed of the opening device is calculated by a computing device using machine data. Method according to claim 5, characterized in that the calculation of the overspeed and the further rotational speed curve of the shedding device also takes into account additional process data, at least the losses of the calculated or estimated loom. The method according to claim 6, characterized in that the calculation of the overspeed and further rotational speed curves of the opening device also takes into account process data based on the loss of the opening device. Method according to claim 6 or 7, characterized in that the calculation of the overspeed and the further rotational speed curve of the opening device also takes into account process data based on the duration of the predetermined start-up phase of the loom. The rotational speed curve of the loom in the predetermined start stage, characterized in that it is defined to include a gradient which decreases toward the time point t3 which is at least the end, according to claim 1 or 2 the method of.

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