Patent Application
20130037647
This application claims priority to co-pending German Patent Application No. DE 10 2011 052 699.4 entitled “Spulmaschine and Verfahren zur Steuerung derselben”, filed Aug. 12, 2011.
The present invention generally relates to a method for controlling a winding machine, wherein continuously supplied or fed winding material, especially a yarn, a thread, a tape, a ribbon, a wire, a twine etc. is simultaneously wound to two or multiple wound packages. During the winding process the packages are positioned and supported by a common spindle. Further, the invention relates to a winding machine. The winding machine simultaneously winds continuously fed winding material to multiple wound packages.
In known winding machines, continuously fed winding material is fed from a supply station. The supply station is in particular built by the production device for the winding material or a stock unit for the winding material. The winding material is fed via a feeding path of the winding machine to a winding station. At the winding station the winding material is processed such that (with the use of a core or without the use a core) a wound package is formed. During the winding process the wound package is supported by a spindle. During the winding process, in the feeding path the winding material is moved in lateral direction and parallel to the spindle by a traversing device. A three-dimensional wound package is formed. In order to provide a constant distance between the outer surface of the wound package and the traversing device even for increasing diameter of the wound package, a pressure roller linked with the traversing device is supported at the outer surface of the wound package. With an increasing diameter of the wound package the required relative movement of the pressure roller and the rotational axis of the wound package might be effected by a movement of the pressure roller with the associated traversing device wherein the rotational axis of the wound package is fixed. For an alternative embodiment the required movement is effected by a stationary pressure roller with traversing device with the use of a moving rotational axis of the wound package. In order to effect a uniform pressing force of the pressure roller over the whole length of the outer surface of the wound package the pressure roller has an orientation parallel to the spindle. The pressure roller also serves for pressing the newly fed winding material at the outer surface of the wound package. The package density of the wound package depends on the pressing force of the pressure roller at the surface of the wound package. The completely wound packages in the end serve for the transportation, the storage and/or the subsequent processing of the winding material.
If the velocity of feeding the winding material from the supply station differs from the winding speed at the winding machine, this results in a change in the length of the winding material in the feeding path. Any such differences in the feeding velocity and the winding velocity might for example result from a varying feeding velocity of the winding material at the supply station (e.g. due to a fluctuating production process of the winding material) and/or from a changed winding velocity at the winding machine (e.g. due to a mis-winding of the winding material, fluctuations of the diameter of the wound package and fluctuations of the diameter of the winding material itself). The change of the length of the winding material in the feeding path might cause a change of the tension in the winding material. Especially for winding processes of sensitive winding materials and/or for winding uniformly wound packages having good unwinding characteristics, it is however favoured to wind the winding material with a tension being as constant as possible. For other applications, during the winding process a change of the tension of the winding material following a predetermined tension characteristic might be favoured. Accordingly, there is the need for appropriate measures to counteract an undesired change of a tension of the winding material or to caused a desired change of an actual tension of the winding material.
One measure for influencing the tension of the winding material is known from European Patent No. EP 1 190 974 B1, corresponding to US Patent Application No. US 2003/0019970 A1. In the winding machine described in this patent, in the feeding path the winding material is guided by a generally stationary roller. The stationary roller is supported by a supporting device at a machine frame. The supporting device has a bending region wherein a sensor senses the tension of the winding material. The sensor is built by a strain gauge. The output signal of the sensor is fed to a control unit which controls a drive mechanism of the spindle. In the control unit, tables or maps can be provided which display a change of a control signal for the drive mechanism of the spindle in dependence on the decrease or increase of a tension of the winding material. The drive mechanism is controlled such that a changed tension of the winding material is counteracted by a change of the winding velocity leading to a changed velocity of taking off the winding material at the wound package. With the winding machine, simultaneously five wound packages are wound in parallel feeding path. The five wound packages are each supported by an associated respective spindle at the machine frame. The patent describes various different designs of the supporting device with the integrated sensor and options for influencing the measurement accuracy of the sensor.
An alternative or cumulative option for influencing the tension of the winding material is known from German Patent No. DE 37 23 593 C1. This patent describes a cross-winding machine. Here, the aim is to automatically decrease the tension of the winding material during the winding process with increasing diameter of the wound package. For that purpose, with an increasing diameter of the outer surface of the wound package a pressure roller linked with a pivoting frame is pivoted. The pivoting movement of the pivoting frame actuates a lever mechanism. By means of the lever mechanism it is possible to adjust a base of a spring. The other base of the spring is coupled to a pivotable dancer arm of a dancer roller. The pivoting angle of the dancer arm is sensed by a sensor. The sensor is formed as a contact-free displacement switch. The switch senses the distance to a cam plate which is pivoted with the dancer arm. Via a control unit (here with a PID-control strategy) the voltage for controlling the drive mechanism of the spindle is controlled with the aim of keeping the dancer arm at a constant pivoting angle. In the end, this control has the result that a desired change of the tension of the winding material is provided with the increase of the diameter of the outer surface of the wound package, with the pivoting movement of the pivoting frame, with the actuation of the lever mechanism and with the adjustment of the base point of the spring. Herein, the changing characteristic is dependent on the kinematics of the pivoting frame, the lever mechanism and the coupling with the dancer arm via the spring.
European Patent No. EP 1 190 974 B1 describes the problem that a slow or inaccurate control of the rotational speed of the wound package results in a changed length of the winding material in the feeding path. A related undesired result is that the tension in the winding material changes in dependence on the difference between the feeding velocity of the winding material by the supply station and the velocity of taking off the winding material by the wound package. The sensitivity also depends on the longitudinal stiffness of the winding material. Hence, any fluctuations of the tension of the winding material directly depend on the quality of the control of the rotational speed of the spindle.
On the contrary, an embodiment known from German Patent No. DE 37 23 593 C1 provides the option of an accommodation of and a compensation for a certain change of the length of the winding material in the feeding path due to a compensating movement of the dancer roller even in case of an inaccurate control of the rotational speed of the wound package. Accordingly, undesired changes of the tension are at least reduced.
In the above publications the mentioned measures for influencing the tension of the winding material are only applicable for winding processes with only one wound package supported by a respective spindle. If two (or more) wound packages are supported by one single common spindle (wherein the wound packages rotate together and are simultaneously wound), it is general not (or only to a limited extend) possible to keep the tension constant by a control of the rotational speed of the wound packages. A compensation of a changed tension of the winding material is only possible by the control of the rotational speed of the wound packages if the required change of the tension of the winding material is the same for both feeding paths to the wound packages with regard to its magnitude and its direction. However, in practice in the two parallel feeding paths different tensions and tension changes often occur. If an adjustment of the rotational speed of one wound package was carried out in order to counteract a change of the winding material in the feeding path to this wound package, this would directly have the undesired result that the tension of the winding material in the parallel feeding path to the other wound package also changes. Here, remedy might be found to some extend, if dancer rollers are applied at each of the feeding paths of the winding material to the wound packages. The dancer rollers are able to individually compensate changes in the length of the winding material in the parallel feeding paths. However, the pivoting of the dancer arm against the loading of a spring might also results in a change of the tension of the winding material wherein the magnitude of this change depends on the spring stiffness. This undesired effect might be reduced by supporting the dancer roller by a pneumatic cylinder instead of a spring. The pneumatic cylinder is (independent on the pivoting angle of the dancer roller) controlled to a constant pressure. The constant pressure effects a constant tension of the winding material independent of the deflection of the dancer roller. However, also for the use of the pneumatic cylinder an undesired change of the tension of the winding material is effected, if the length of the winding material exceeds the maximum displacement of the dancer roller, so that the dancer roller has reached an end position wherein no further compensating movement is possible.
From German Patent Application No. DE 27 21 972 A1, corresponding to British Patent Application No. GB 1 601 523, a method and an apparatus for winding winding material to a wound package are known. Here, the winding velocity is adjustable. The wound package is driven by a pressure roller. Either the wound package or the pressure roller is cylindrical whereas vice versa the pressure roller or the wound package is conical or biconical. The wound package is pivotable relative to the pressure roller. Thus, it is possible to vary the distribution of the contact pressure between the wound package and the pressure roller without a change of the averaged overall pressing force. This variation is controlled with the aim to increase or decrease the winding velocity. The tension of the fed winding material serves as a control parameter for controlling the amount and the direction of the pivoting movement. For driving several wound packages by a single pressure roller, each wound package separately pivoted.
Also German Patent Application No. DE 25 13 981 A1, corresponding to U.S. Pat. No. 4,120,462, discloses a method and an apparatus for controlling the tension of winding material. The tension of the winding material is continuously sensed and controlled in dependence on a deviation from a preset value. The control uses a pivoting movement of the wound package relative to a pressure roller. The pressure roller is in contact with the wound package along a contact line and acts as a driving roller for driving the wound package. The pressure roller is formed conically. Accordingly, a pivoting movement has the result that the contact pressure between the wound package and the pressure roller is increased in direction of one of the ends of their contact line. Since the wound package is driven by the pressure roller in the region of the highest contact pressure, the circumferential velocity of the wound package depends on the pivoting movement. Thus, the winding velocity of the winding material is changed with the pivoting movement with the aim to keep the tension of the winding material at a set value.
In the winding machine known from U.S. Pat. No. 4,184,646, a change of the tension of a fed winding material is sensed via a strain gauge. Based on the signal of the strain gauge, a control signal for an actuator is generated. The actuator pivots a wound package relative to a pressure roller. Due to the pivoting movement of the wound package, the contact pressure between the wound package and the driving pressure roller is varied such that the winding velocity is increased or decreased and the tension is controlled to a set value.
According to Patent Applications No. DE 27 21 972 A1, DE 25 13 981 A1 and U.S. Pat. No. 4,184,646, the tension is changed by a direct control of the rotational speed of the wound package: Here, the pressure roller is driven by a motor with a driving rotational speed n1, wherein the pressure roller drives the wound package via a friction drive with a drive ratio i. Thus, the pressure roller drives the wound package with a rotational speed n2=i×n1. The rotational speed n2 of the wound package is controlled via a change of the drive ratio i of the friction drive. It is suggested to change the drive ratio i of the friction drive on the basis of two different mechanisms:
To conclude, according to the last mentioned prior art a control of a tension of winding material is achieved by directly controlling the rotational speed of a wound package or indirectly controlling the rotational speed of a wound package by a change of a drive ratio i of a friction drive.
It is the object of the invention to provide a method for controlling a winding machine which provides advanced or alternative options
Further, it is the object of the invention to provide a winding machine which provides an improved control of
According to the present invention, the object of the invention is solved by the features of the independent claims. Further embodiments of the present invention are specified in the dependent claims.
The present invention bases on the finding that the known measures for controlling the tension of the winding material base on the prejudice that it is only possible to influence the tension of the winding material by use of a dancer roller and/or by the controlling of the rotational speed of the wound package. Contrary to this prejudice, the invention proposes to use further alternative or cumulative measures for influencing the tension of the winding material as follows:
According to an embodiment of the invention, continuously fed winding material is wound in parallel and simultaneously to two (or more) wound packages. The wound packages are supported by a common spindle and driven together by a common spindle. Accordingly, the wound packages rotate together with the same rotational speed. (In this context, “winding in parallel” means that the wound packages are simultaneously wound, wherein this does not mean that the winding material is fed to the wound packages in parallel in terms of geometry.)
In a method according to the invention, (at least) one control signal is generated and (at least) one actuator is actuated by the control signal. The actuator might be of any kind, especially an electric, a pneumatic or a hydraulic actuator. The actuator changes the pressing force of (at least) one pressure roller pressing at (at least) one wound package in dependence on the (at least) one control signal. The invention covers embodiments wherein only the pressing force of one pressure roller pressing at one wound package might be changed, whereas a pressing force of another pressure roller remains unchanged. However, it is also possible that the pressing force of at least one pressure roller simultaneously contacting and pressing at (at least) two wound packages is changed in common. The pressing force correlates with the distance of the pressure roller from the rotational axis of the wound package, the package density and the radial stiffness of the wound package. Thus, the invention also comprises an embodiment in which the actuator is controlled to an increasing or decreasing distance of the pressure roller from the rotational axis of the wound package instead of an increasing or decreasing pressing force of the pressure roller pressing at the wound package. Furthermore, the force of the at least one actuator might directly influence the pressing force or correspond to the pressing force. It is also possible that the actuator provides only one component of the pressing force, whereas another component is provided by other measures, e.g. by a further actuator and/or a weight of the pressure roller and the traversing mechanism. For a special embodiment, the actuator is responsible for an individual change of the pressing force for the corresponding winding of at least one wound package with regard to a predetermined (averaged or normal) pressing force characteristic, whereas the predetermined (averaged or normal) pressing force characteristic is provided by the overall weight of the traversing mechanism and the pressure roller and/or a further actuator. Finally, it is also possible that by the at least one actuator only a changed pressing force characteristic is effected, whereas the overall pressing force remains unchanged.
According to the invention, a directly or indirectly sensed tension of the winding material is not (exclusively) used to change the position of a dancer roller and/or to control the driving rotational speed of the wound package. The (at least) one control signal is determined in dependence on the tension of the winding material, especially the tension of the winding material at a feeding path to one wound package or to both or more wound packages. Via this control signal, the bias of the actuator and thus the pressing force is influenced. Alternatively or additionally, the at least one control signal is determined in dependence on the deflection of at least one dancer roller.
According to the invention, a change of the pressing force results from a change of the tension of the winding material or a change of the deflection of the dancer roller due to the action of the changed control signal to the actuator. To give only some examples, an increase of the tension of the winding material can effect an increase of the pressing force. The increase of the pressing force has the result that the package density of the winding is (slightly) changed. The change of the density has the result that the radius R of the outer surface of the wound package is decreased at least at that position where the winding material is wound on the wound package. Thus (considering the simplifying assumption of a constant angular velocity ω of the wound package), the winding material is taken off with a reduced velocity ωR, whereby the increased tension of the winding material can be counteracted. Correspondingly, in the opposite case a decrease of the tension of the winding material results in a controlled decrease of the pressing force with a resulting increased radius R and increased velocity ωR. (Likewise, an increased deflection of a dancer roller might be counteracted by increasing the pressing force of the pressure roller.)
The inventive measure of influencing the tension of the winding material and/or of the deflection of the dancer roller might be exclusively carried out by the before mentioned change of the pressing force or alternatively or cumulatively by influencing the rotational speed of the wound package. Here, it is possible to control different pressing forces pressing at the parallel wound packages for a compensation of different tensions of the winding material and/or a compensation of different deflections of dancer rollers at the different parallel feeding paths.
According to the invention, the tension of the winding material and/or the deflection of the dancer roller at the feeding path of the winding material to one or several wound packages is sensed and processed separately for each feeding path. For sensing the tension and/or of the deflection of the dancer roller various options are known.
According to the invention, the wound packages are driven by the spindle, whereas for the prior art mentioned in the beginning a friction drive is used for driving the wound packages. For winding machines basing on a friction drive the wound package is typically wound with a pattern according to the so-called “constant angle winding” or “random winding”. This results from the fact that due to the friction drive the circumferential velocity of the wound package is determined by the pressure roller. Supposing a constant rotational driving speed of the friction drive (disregarding an eventual slip) the circumferential velocity of the friction drive remains constant with increasing radius of the wound package. Thus, the ratio of the winding material's velocity and of the traversing velocity remains constant for a constant traversing motion. Accordingly, the winding angle of the winding material does not change with increasing diameter of the wound package. However, because of the increasing radius of the wound package the winding ratio changes. The result of this is that the number of windings per layer changes during the winding process. Apart from the winding patterns according to “constant angle winding” or “random winding”, there are also known windings of the type “precision winding”. The “precision winding” is for example achieved, when the wound package is supported by a spindle and driven by this spindle. In contrast to the “constant angle winding” or “random winding”, for the “precision winding” it is necessary to keep the ratio of the angular velocity of the spindle to the traversing velocity constant. This n is difficult for a frction drive but easy to achieve when driving the spindle.
According to the invention, the wound packages are driven by their common spindle. It is possible to produce wound packages with patterns both of the type “constant angle winding” and “random winding” as well as of the type “precision winding” (wherein there are various possibilities of controlling the driving speed of the wound package(s) and the traversing mechanism(s)).
The invention also suggests calculating a control signal that depends on a tension of the winding material and/or a deflection of at least one dancer roller as follows:
The invention covers both embodiments wherein the tension or deflection compared with the desired or predetermined tension or deflection is an absolute tension or deflection within the feeding path as well as embodiments wherein the tension or deflection is a difference of the tensions or deflections in the different feeding paths.
For a special embodiment of the invention, the tension of the winding material is sensed by supporting of a roller for the winding material by a supporting means. The tension in the winding material results in a bias of the supporting means which is sensed by an appropriate sensor. For example, for sensing the tension of the winding material a supporting means as described in EP 1 190 974 B1 might be used in line with the invention, wherein the bias is determined via a strain gauge. Also an alternative supporting means as described in German Patent No. DE 10 2008 032 643 B3, corresponding to Japanese Patent Publication No. JP 2000226154 A, which might be applied in line with the invention for sensing the tension of the winding material. However, the supporting means used according to the invention and the applied sensor are not restricted to the above examples.
A sensor for sensing the deflection of a dancer roller might sense the translational movement along a translational degree of freedom of the dancer roller or a pivoting angle of a dancer arm for example. In the different feeding paths to different wound packages the same or different sensors might be applied, e.g. a sensor basing on a supporting means of the roller and another sensor sensing the movement of a dancer roller. It is also possible that in one or each feeding path different redirecting units with corresponding sensors are provided in a row.
It is possible that the rotational speed of the wound package is kept constant or depends on a predetermined characteristic. Furthermore, a control of the rotational speed of the wound packages might be carried out in dependence on any operating parameters, for example in dependence on a feeding velocity of the winding material in the region of the supply station. In a preferred embodiment, the rotational speed of the wound packages is (only or also) controllable in dependence on the tension of the winding material and/or a deflection of the at least one dancer roller. Thus, for a change of the tension of the winding material and/or a change of the deflection of the dancer roller by the control of the pressing force (alternatively or cumulatively) the control by the rotational speed might be used. Here, the parallel wound packages are driven with the same controlled rotational speed. In line with the invention, the wound packages are driven by the spindle.
In a preferred embodiment of the invention, the rotational speed of the wound packages is controlled in dependence on several tensions or deflections which are each sensed at parallel feeding paths of the winding material to the wound packages.
In a further embodiment of the invention, the rotational speed of the wound packages is controlled in dependence on an average value of tensions or deflections which are each sensed at parallel feeding paths of the winding material to the wound packages. This is explained on the basis of the following simple but non limiting example: For this example in both feeding paths dancer rollers are provided. The dancer rollers are deflected according to the actual tension or according to the length of the winding material in these feeding paths.
Case A: common or unique pivoting movement of the dancer rollers: A common pivoting of the dancer arms might be compensated by a mere change of the rotational speed of the common drive mechanism for the wound packages.
Case B: pure relative pivoting movement of the dancer rollers: If the dancer arms of both of the dancer rollers in the two parallel paths are pivoted relative to each other, this relative pivoting of the dancer arms will be compensated by a relative change of the pressing forces of the pressure roller pressing at both of the corresponding wound packages.
Case C: Mixed compensation: If both a component with a unique movement of both dancer rollers as well as a component with a relative movement of both dancer rollers occur, this might be compensated by a cumulative control
In a special embodiment of the invention, separate pressure rollers are applied for each of two (or more) wound packages. In order to be able to effect a compensation for a tension of the winding material at one feeding path, an individual change of the pressing force of one pressure roller pressing at the corresponding wound package might be effected by a movement or displacement of the pressure roller in radial direction relative to the rotational axis of the wound package. It is not compulsory that the other the pressure roller also changes its position relative to the spindle or that an additional, individual movement or displacement of the other pressure roller is effected. In this manner, the velocity of taking off by that wound package with the associated displaced pressure roller is individually be effected. Thus, the tension of the winding material which is fed to this wound package and/or the deflection of the at least one dancer roller can be individually effected.
Another embodiment of the invention transfers a design known from DE 100 03 513 A1 to another application and control: DE 100 03 513 A1 describes the problem that in the case of winding several wound packages located at a single spindle the weight distributed along the spindle increases during the winding process. The increasing weight effects an increasing bending and deflection of the spindle. The bending deflection has the result that the pressing force of a single pressure roller responsible for all of the wound packages varies for each of the wound packages corresponding to the effected bending deflection line. In order to provide a constant pressing force at all of the wound package despite of the effected bending deflection line, DE 100 03 513 A1 proposes to replace one single end-to-end pressure roller by several, separate pressure rollers which are each associated with a single wound package. Each of the pressure rollers can be adjusted and actuated by an actuator in radial direction relative to the longitudinal axis of the wound package such that each pressure roller is pressed at the wound package with the same pressing force. Such an embodiment with various pressure rollers according to DE 100 03 513 A1 might also be used in line with the present invention. However, according to the invention another strategy for controlling the actuators corresponding to the individual pressure rollers is used: According to the invention, the pressing force of the pressure rollers pressing at the outer surfaces of the wound packages is not controlled to be as constant as possible. Instead, according to the invention, the pressing force is selectively and individually increased or decreased in order to counteract a changed tension of the winding material or a deflection of a dancer roller.
According to another embodiment basing on the use of several pressure rollers, an adjustment of different tensions occurring in the feeding paths of the winding material to the different wound packages is effected by moving a pressure roller in radial direction relative to the rotational axis of the spindle towards the spindle for increasing the pressing force and for decreasing the tension of the winding material and/or of the deflection of a dancer roller in the corresponding feeding path. The other pressure roller is moved in radial direction relative to the rotational axis of the spindle away from the spindle for decreasing the pressing force and for increasing the tension of the winding material and/or of the deflection of the dancer roller in the corresponding feeding path. It is possible but not required that in addition to these measures the rotational speed of the wound packages is controlled.
In an alternative approach according to the invention a change of the pressing force might be effected by a change of the angle of the rotational axis of the pressure roller relative to the rotational axis of the spindle. Here, the change of the angle is effected by (at least) one actuator. Due to this change of the angle the outer surface of the winding is (at least in the contact region with the pressure roller) deformed to a truncated cone corresponding to the outer surface of the pressure roller. In dependence on the position where the winding material is laid on the outer surface of this truncated cone, a change of the diameter is effected. This results in a changed velocity of taking off the winding material. The opening angle of the truncated cone depends on the angle of the rotational axis of the pressure roller relative to the rotational axis of the wound package. This measure can also be applied for the use of separate pressure rollers for each wound package. Preferentially, however, this measure is applied for a pressure roller which is in contact with the outer surfaces of and drives at least two wound packages. A change of the angle of the pressure roller is effected for example such that the largest diameter of the truncated cone of a wound package is smaller than the smallest diameter of the truncated cone of the other wound package. Thus, different diameters of the wound packages and thus velocities of taking off the winding material at the different feeding paths can selectively be achieved. This might be used for compensating different tensions of the winding material in the different feeding paths and/or of the deflections of the dancer rollers in these feeding paths.
Another solution of the object of the invention is provided by a winding machine, wherein by means of the winding machine continuously fed winding material is wound in parallel to at least two wound packages. The winding machine comprises a spindle which drives the wound packages at at least two winding stations. At each winding station at least one wound package is located. At the winding stations simultaneous winding processes of the winding material are carried out. The winding machine comprises one single pressure roller for a plurality of wound packages or a plurality of pressure rollers which might be each associated with only one wound package or a subgroup of wound packages. The winding machine further comprises at least one actuator which is controllable by a control signal. By the at least one actuator, the distance of one of the pressure rollers or the distance of several pressure rollers are adjustable and/or the pressing forces of at least one pressure roller pressing at the wound packages are adjustable. According to the invention, a sensor is provided which senses a tension of the winding material and/or of a deflection of a dancer roller in a feeding path to a corresponding wound package. It is also possible that several sensors are provided for the different feeding paths. Furthermore, the winding machine according to the invention comprises a control unit which comprises control logic for controlling the tension in the winding material and/or the deflection of the dancer roller. According to the invention, the control logic determines a control signal, wherein the control signal depends on the tension in the winding material and/or the deflection of the dancer roller. The control signal controls the actuator for counteracting a change of a tension of the winding material and/or of the deflection of the dancer roller as described before.
In a further embodiment of the inventive winding machine, a separate sensor is provided at each of the parallel feeding paths of winding material to the winding stations, wherein each sensor is provided for sensing the tension of the winding material and/or the deflection of the dancer roller.
In general, the sensor might be of any type. The sensor might sense a bias of a supporting means for a roller. The sensor might also sense a strain or extension, a tension or a force in the supporting means which is caused by the bias by the tension of the winding material. It is also possible that a sensor is used which senses the deflection of a dancer roller.
Advantageous developments of the invention result from the claims, the description and the drawings. The advantages of features and of combinations of a plurality of features mentioned at the beginning of the description only serve as examples and may be used alternatively or cumulatively without the necessity of embodiments according to the invention having to obtain these advantages. Without changing the scope of protection as defined by the enclosed claims, the following applies with respect to the disclosure of the original application and the patent: further features may be taken from the drawings, in particular from the illustrated designs and the dimensions of a plurality of components with respect to one another as well as from their relative arrangement and their operative connection. The combination of features of different embodiments of the invention or of features of different claims independent of the chosen references of the claims is also possible, and it is motivated herewith. This also relates to features which are illustrated in separate drawings, or which are mentioned when describing them. These features may also be combined with features of different claims. Furthermore, it is possible that further embodiments of the invention do not have the features mentioned in the claims.
Other features and advantages of the present invention will become apparent to one with skill in the art upon examination of the following drawings and the detailed description. It is intended that all such additional features and advantages be included herein within the scope of the present invention, as defined by the claims.
The invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring now in greater detail to the drawings,
In the following, the path of the winding material 2a, 2b via the feeding paths 4a, 4b is described for the winding material 2a via the feeding path 4a in the first line (wherein the corresponding applies for the winding material 2b in the parallel feeding path 4b):
The winding material 2a leaves a supply station 6 not depicted in the figures with a delivering velocity 5a. The winding material 2a is redirected by a first, stationary roller 7a towards a movable dancer roller 8a. The dancer roller 8a in turn redirects the winding material 2a towards a stationary roller 9a. The stationary roller 9a located approximately in the same height as the roller 7a. The roller 9a again redirects the winding material 2a towards a traversing guide (not shown in the figures). For the illustrated embodiment, the dancer roller 8a is rotatably linked with a dancer arm 11a which is pivotably supported in pivoting directions 10a. A reduction of the length of the winding material 2a within the feeding path 4a correlates with a counter-clockwise pivoting of the dancer arm 11a. This pivoting movement also correlates with an increase of the tension of the winding material 2a. (In the case that—as mentioned in the beginning—the dancer arm 11a is not supported via a spring, but via a pneumatic cylinder, which is controlled to a constant pressure, the change of the deflection of the dancer arm 11a does not correlate with a changed tension of the winding material 2a, but only with a changed length of the winding material 2a within the feeding path 4a.) Correspondingly, the increase of the length of the winding material 2a at the feeding path 4a results in a clockwise pivoting movement of the dancer arm 11a according to
By the traversing mechanism (not shown in the figures) a traversing movement 12a for building a fan angle between the roller 9a and the traversing mechanism. From the traversing mechanism the winding material 2a is delivered to the outer surface of a pressure roller 13 which is pressed at the outer surfaces 14a, 14b of the wound packages 3a, 3b. The winding material 2a moves in contact with the pressure roller 13 along a part of the circumference. Then, the winding material 2a is laid upon the outer surface 14a of the wound package 3a (preferentially in a contact region of the pressure roller 13 with the wound package 3a).
Preferably, the traversing mechanisms are part of a common yarn guiding and pressing unit 33 and supported by the pressure roller 13 at the wound packages 3a, 3b. The wound packages 3a, 3b are supported by a common spindle 18. The spindle 18 extends in a direction vertical to the drawing plane of
The dancer arms 11a, 11b are pivotable separate from each other. Especially from
From
In the case of a pivoting movement with the angle 24 as illustrated in
Many modified embodiments are possible. For example, the actuator 21 might be omitted, whereas in this end region the pressure roller 13 is supported by a pivot bearing with a fixed position at the yarn guiding and pressing unit 33. In this case the rotational axis 16 is pivoted about this pivot bearing by controlling one single actuator 20 instead of two actuators. Only due to an adjusting movement 22 the pressure roller 13 is pivoted about the pivot bearing with an angle 24. (Here, the angle 24 is to be measured at the pivot bearing.)
In this embodiment and in other embodiments, the tensions of the winding material 2a, 2b and/or the deflections of the dancer rollers 8a, 8b might additionally influenced by a control of the rotational speed of the wound packages 3 of the spindle 18, respectively. For example in the case of using of the single actuator 20 as described, the pivoting of the rotational axis 16 of the pressure roller 13 goes along with the fact that an increase or decrease of the tension of the winding material 2a, 2b occurs at both feeding paths 4a, 4b, but to different extents depending on the distance of the traversing mechanism from the pivot bearing. In this case, an additional, superimposed influencing might occur due to an adjusted rotational speed of the wound packages 3a, 3b.
For the illustrated embodiment, it is assumed that the wound packages 3a, 3b rotate together with the same rotational speed.
In a further embodiment, each of the wound packages 3a, 3b is assigned to an individual pressure roller 13a, 13b, wherein these two pressure rollers 13a, 13b are each separately controllable by two actuators 20a, 21a and 20b, 21b. In this case, it is not compulsory that a change of the angles of the pressure rollers 13a, 13b is effected, but it is optional. Preferentially however, a parallel movement or displacement of the pressure rollers 13a, 13b is effected with different distances 15a, 15b of the pressure rollers 13a 13b from the rotational axis 17 for compensating the different tensions in the feeding paths 4a, 4b. For further details it is referred to the embodiments of the pressure rollers, actuators, degrees of freedom and supports as well as bearings according to DE 100 03 513 A1, wherein all these embodiments might be integrated into the present invention (however, with a changed concept of the control).
Measurement signals 27a, 27b are supplied to a control unit 28 which generates appropriate control signals to counteract deviations of tensions of the winding materials 2a, 2b at the feeding paths 4a, 4b from set tensions or to counteract changes of the deflections of the dancer rollers 8a, 8b. For example, the control unit 28 generates control signals 29, 30 which control the actuators 20, 21 (or actuators 20a, 21a, 20b, 21b) to control a change of a distance 15 and/or a change of the angle 24. In
The solutions known from the before mentioned prior art are only suited to limited extent for controlling a length of the winding material within the paths or for controlling a tension, when winding material 2a, 2b is simultaneously wound to several wound packages 3a, 3b positioned on one single spindle 18. In case of large differences in the running time of the winding material, it cannot be avoided that different tensions of the winding material 2a, 2b occur at the separate wound packages 3a, 3b and thus that different characteristics of the wound packages result. In the worst case, processing errors might occur already during the winding, especially as a winding material 2a, 2b can no longer be guided because of the tension becoming too low or as damages of the winding material 2a, 2b or the machine occur because of too high tension. According to the invention, the angle 24 is actively controlled such that a control of the amount of winding material taken off by the separate wound package 3a, 3b is adjusted. As the pressing force of the pressure roller 13 pressing at one or several wound packages 3a, 3b is reduced by the change of the angle 24, the density of the wound packages 3a, 3b is reduced, and thus, the diameter of the wound packages 3a, 3b is increased. This in turn has the result that the length of the winding material 2a, 2b which is taken off is controlled and adjusted also for a constant angular velocity of the wound packages 3a, 3b. The same applies vice versa for winding packages that are exposed to an increased contact pressure.
In order to determine the required winding velocity the actual length of the winding material 2a, 2b, i.e. a position of a dancer roller 8a, 8b, is continuously sensed in each of the paths 4a, 4b. The sensor signals are supplied to the control unit 28. In the control unit 28, the sensed values are compared, and a required change of the angle 24 of the pressure roller 13 relative to the spindle 18 is calculated on the basis of the determined differences. This calculated angle 24 is then directly or indirectly applied by means of one or more actuators 20, 21 at the winding machine 1, e.g. by use of a leverage. Hereby, the distance of the pressure roller 13 from the spindle axis is increased with increasing length of the winding material 2a, 2b. Correspondingly, its distance from the wound packages 3a, 3b is reduced with reduced length of the winding material 2a, 2b. Further. it is possible to use a method wherein a separate pressure roller 13a 13b is provided for each of the wound packages 3a, 3b. In this case, each of the separate pressure rollers 13a, 13b is oriented parallel to the spindle 18 in a controlled distance to the spindle 18. At the same time with the control of the pressure roller 13 or the pressure rollers 13, 13b it is possible to calculate a required rotational speed or a required change of the rotational speed of the spindle 18 from the measured tensions of the winding material 2a, 2b by averaging, from any other weighed averaging or from any other functional dependency of the tension or from an evaluation of the differences of the tensions. The calculated values or signals are then used for controlling drive 32 accordingly.
In the course of the present invention, the term “change of the pressing force” comprises a change in the magnitude of the pressing force and/or a change of the distribution of the pressing force along the contact line or contact surface of the pressure roller with the outer surface of the package or packages.
In the illustrated embodiment, both actuators 20, 21 are supported at the pressure roller 13 in one end region, whereas in the other end region the actuators 20, 21 are supported at the yarn guiding and pressing unit 33. In this embodiment, the whole resulting pressing force acting on the wound packages 3a, 3b is independent from the adjusting movements 22, 23. However, in dependence on the angle 24 it is possible to influence the distribution of the pressing forces. Here, the resulting pressing force depends on the weight of the yarn guiding and pressing unit 33 and/or additional actuators biasing the yarn guiding and pressing unit 33 (these optional additional actuators are not illustrated in the figures).
It is also possible that the actuators 20, 21 or additional actuators act on the yarn guiding and pressing unit 33. In this case, the distance 15 might be changed for adjusting movements 22, 23 of equal magnitude and of equal orientation and for maintaining the parallelism of the rotational axes 16, 17. Concurrently, it is possible to change the package density of the wound packages 3a, 3b and to change the tension at both feeding paths 4a, 4b simultaneously or to effect a common change of the pivoting angle 10a, 10b of the dancer arms 11a, 11b. If the design provides an appropriate degree of freedom, the distribution of the pressing force at the wound packages 3a, 3b can be adjusted by a pivoting movement of the yarn guiding and pressing unit 33 together with the pressure roller 13 about the angle 24 as described before. Due to a superimposed change of the distance 15 on the one hand and a change of the angle 24 on the other hand, both a direct component of the changed pivoting angle 10a, 10b as well as a relative change of the pivoting angle 10a, 10b can be compensated for.
As mentioned before, it is possible that also two separate pressure rollers 13a, 13b are biased by pairs of actuators 20a, 21a and 20b, 21b, respectively. The pairs of actuators are each provided for one respective wound package 3a, 3b. In this case, the actuators 20a, 20b, 21a, 21b are preferably supported at the yarn guiding and pressing unit 33. Here, a separate adjustment of the distances 15a, 15b of the pressure rollers 13a, 13b from the rotational axis 17 can be effected, wherein alternatively or additionally also the angle 24a, 24b of the pressure rollers 13a, 13b might be influenced.
Many variations and modifications may be made to the preferred embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of the present invention, as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1020110526994 | Aug 2011 | DE | national |
