YARN WINDING DEVICE AND YARN WINDING METHOD Field of the Invention
The present invention relates to a yarn winding device. Specifically, the present invention relates to a configuration and a method for controlling vibration of a cradle provided in the yarn winding device.
Background of the Invention
For yarn winding devices such as automatic winders, an increase in speed at which a yarn is wound around a winding bobbin has been desired in order to improve package productivity. On the other hand, an excessive increase in the rotation speed of the package may cause a cradle to vibrate greatly during a winding operation. As a result, a surface of the package may be damaged, and in an extreme case, the package may slip out of the cradle. Thus, in a known configuration of a conventional automatic winder, an upper limit is set for the winding rotation speed so that the level of the vibration falls within a tolerable range. The winding speed is thus controlled within the speed range having such an upper limit.
In particular, at the start of winding of the package, the rotation of the package is likely to be unstable due to the adverse effect of, for example, distortion of the winding bobbin. For example, an eccentric winding bobbin increases the level of the vibration. In view of this, the conventional automatic winder may adopt a configuration in which a package rotation speed is set low at a start of a winding operation (what is called touch winding) and in which when
the winding progresses and a winding diameter of the package increases to some degree, the touch winding is canceled and a process of increasing the rotation speed to the upper limit is executed.
However, due to individual differences among the winding bobbins or winding units, the rotation speed at which vibration exceeding the tolerable range varies. In this regard, the conventional control system uses a uniform touch winding speed or upper limit speed for a plurality of winding units. The conventional control system is thus forced to set a low winding speed by providing a large margin enough to prevent untorerable vibration from occurring in all the winding units. Thus, with the conventional control system, the capability of the winding units in the automatic winder as a whole cannot be effectively utilized. Consequently, increasing the efficiency of package production is difficult.
In this regard, the Unexamined Japanese Uti 1 ity Model Application Publication (Jikkai-Hei) No. 2-43876 discloses a configuration which includes an abnormal-vibration sensor in the cradle that detects vibration, and if vibration determined to be abnormal occurs, stops the package winding. The Unexamined Japanese Patent Application Publication (Tokkai-Hei) No. 6-127833 discloses a configuration which, upon determining the vibration to be abnormal, notifies an operator of the abnormal vibration through an alarm display or the like.
However, the configurations disclosed in the Unexamined Japanese Utility Model Application Publication (Jikkai-Hei) No. 2-43876 and the Unexamined Japanese Patent Application Publication (Tokkai-Hei) No. 6-127833 do not actively control
the vibration but simply detects the abnormal vibration. In particular, the configuration in the Unexamined Japanese Utility Model Application Publication (Jikkai-Hei) No. 2-43876 stops the package winding when the abnormal vibration occurs, and thus cannot avoid reducing the productivity.
Summary of the Invention
An object of the present invention is to provide a yarn winding device and a yarn winding method which allow winding speed to be controlled according to the vibration of a cradle during a winding operation.
According to an aspect of the present invention, a yarn winding device includes a cradle, a vibration detecting section, and a rotation speed detecting section. The cradle rotatably supports a package. The vibration detecting section detects intensity of vibration of the cradle. The rotation speed control section controls rotation speed of the package. The rotation speed control section allows the vibration detecting section to monitor vibration of the cradle, and controls the rotation speed of the package according to the detected vibration intensity.
Thus, the rotation speed of the package can be appropriately controlled with possible excessive vibration prevented. As a result, the package productivity can be improved.
In the yarn winding device, the rotation speed control section includes a comparison section and a speed increase section. The comparison section compares
the vibration intensity detected by the vibration detecting section with a set intensity. The speed increase section increases the rotation speed of the package if a result of the comparison by the comparison section indicates that the vibration intensity detected by the vibration detecting section is equal to or lower than the set intensity.
Thus, the winding speed of the package can be increased within the limit in which the vibration does not become excessive. In particular, the winding speed of the package can be quickly increased, with the package prevented from flapping excessively during an increase in speed at the start of the winding of the package. Therefore, the package productivity can be improved.
In the yarn winding device, the rotation speed control section includes a speed reduction section. The speed reduction section reduces the rotation speed of the package if the result of the comparison by the comparison section indicates that the vibration intensity detected by the vibration detecting section is higher than the set intensity.
Thus, if excessive vibration occurs or is likely to occur, the rotation speed of the package can be reduced to a speed at which the level of the vibration falls within a tolerable range, and the yarn winding device can continue the winding operation. Accordingly, the package can be prevented from being damaged due to the vibration. Furthermore, this configuration allows the productivity to be improved compared to a configuration that stops the winding operation when an abnormal vibration occurs.
In the yarn winding device, the rotation speed control section includes a winding progression degree acquiring section that acquires degree of progression of winding from start of the package winding. The speed reduction section reduces the rotation speed of the package only if the winding progression degree acquired by the winding progression degree acquiring section is equal to or lower than a predetermined winding progression degree.
Thus, at winding start when, for example, the eccentricity of a core tube (winding bobbin) of the package is likely to cause excessive flapping, the speed reduction control can be performed to prevent the quality of the package from being degraded by excessive vibration. That is, before the speed reduction control, the yarn winding device acquires the degree of progression of package winding from the start of the winding to determine whether or not the touch winding, for which the rotation speed of the package is set low, is completed. If the acquired winding progression degree is equal to or lower than a predetermined progression degree, that is, if the touch winding is not completed, the speed reduction process is carried out according to the intensity of vibration of the cradle. As a result, the yarn winding device can appropriately prevent the quality of the package from being degraded by the excessive vibration during the touch winding, when the package is likely to flap.
After the winding progresses to a given degree and a sufficient yarn layer is formed on the package, that is, after the touch winding is completed, the speed reduction process is not carried out because the yarn layer is expected to exert
a vibration buffering effect. As a result, after the touch winding is completed, the yarn is prevented from being wound by such slow rotation as not intended by an operator. Therefore, the package can be wound with the winding speed increased up to the limit. This allows the package productivity of the yarn winding device to be improved.
Another aspect of the present invention provides the following yarn winding method. That is, the yarn winding method includes a step of detecting intensity of vibration of a cradle that supports a rotating package, and a step of controlling rotation speed of the package according to the detected vibration intensity.
Thus, the rotation speed of the package can be appropriately controlled with the vibration prevented from becoming excessive. As a result, the package productivity can be improved.
Other features, elements, processes, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention with reference to the attached drawings.
Brief Description of the Drawings
Figure 1 is a schematic view of a winder unit provided in an automatic winder according to a first embodiment of the present invention.
Figure 2 is a flowchart of yarn winding speed control in the automatic winder
according to the first embodiment.
Figure 3 is a schematic view of a winder unit provided in an automatic winder according to a second embodiment of the present invention.
Figure 4 is a flowchart of yarn winding speed control in the automatic winder according to the second embodiment.
Figure 5 is a graph showing an example of an angular signal from an angle sensor.
Detailed Description of the Preferred Embodiments
Preferred embodiments of the present invention will be described below with reference to the drawings.
A winder unit 10 shown in Figure 1 winds a spun yarn 20 unwound from a supplying bobbin 21, around a winding bobbin 22 while traversing the spun yarn 20. The winder unit 10 thus forms a package 30 of a predetermined length and a predetermined shape. An automatic winder (yarn winding device) according to the present embodiment includes a plurality of winder units 10 arranged in a line and a frame control device (not shown in the drawings) located at one end of the arrangement of the winder units in the direction of the arrangement.
Each of the winder units 10 includes a winding unit main body 16 and a unit control section 50.
The winding unit main body 16 includes a balloon controller 12, a tension applying device 13, a splicer device 14, and a clearer (yarn quality measurement
instrument) 15 arranged in this order in a yarn traveling path between the supplying bobbin 21 and a winding drum 24; the balloon controller 12 is located closest to the supplying bobbin 21.
The balloon controller 12 lowers a regulation member 40 covering a core tube in conjunction with unwinding of a yarn from the supplying bobbin 21. The balloon controller 12 thus assists unwinding the yarn from the supplying bobbin 21. The regulation member 40 makes contact with a bal loon formed above the supplying bobbin 21 by the rotation and centrifugal force of the yarn unwound from the supplying bobbin 21. The regulation member 40 thus applies an appropriate tension to the balloon to assist unwinding of the yarn. A sensor (not shown in the drawings) is provided in the vicinity of the regulation member 40 to detect a chase portion of the supplying bobbin 21. When the sensor detects that the chase portion is lowering, the regulation member 40 can be lowered in conjunction with the lowering of the chase portion by an air cylinder (not shown in the drawings).
The tension applying device 13 applies a predetermined tension to the traveling spun yarn 20. The tension applying device 13 may be of, for example, a gate type in which movable comb teeth are arranged with respect to fixed comb teeth. The movable comb teeth may be moved by, for example, a rotary solenoid so that the movable comb teeth are engaged or released with respect to the fixed teeth. The tension applying device 13 applies a given tension to the yarn being wound to improve the quality of a package 30. Instead of the gate type, the tension applying device 13 may be of, for example, a disc type.
When the spun yarn 20 is cut due to detection of a yarn defect by the clearer 15 or the spun yarn 20 is broken during unwinding of the spun yarn 20 from the supplying bobbin 21, the splicer device 14 splices a lower yarn on the supplying bobbin 21 side and an upper yarn on the package 30 side.
A sensor (not shown in the drawings) is provided in a clearer head 49 of the clearer 15 to detect the thickness of the spun yarn 20. The clearer 15 monitors a yarn thickness signal from the sensor to detect a yarn defect. A cutter (not shown in the drawings) is provided in the vicinity of the clearer head 49 to cut the spun yarn 20 immediately after the clearer 15 detects a yarn defect.
A lower-yarn guide pipe 25 is provided below the splicer device 14 to catch a lower yarn on the supplying bobbin 21 side to guide the lower yarn to the splicer device 14. An upper-yarn guide pipe 26 is provided above the splicer device 14 to catch an upper yarn on the package 30 side to guide the upper yarn to the spl icer
device 14. The lower-yarn guide pipe 25 is pivotally movable around a shaft 33.
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The upper-yarn guide pipe 26 is pivotally movable around a shaft 35. A suction port 32 is formed at a tip of the lower-yarn guide pipe 25. A suction mouth 34 is formed at a tip of the upper-yarn guide pipe 26. Appropriate negative pressure sources are connected to the lower-yarn guide pipe 25 and the upper-yarn guide pipe 26, respectively. Accordingly, suction flow is generated at the suction port 32 and the suction mouth 34 to suck and catch yarn ends of the upper yarn and the lower yarn.
A cradle 23 and a winding drum (traverse drum) 24 are provided further above
the splicer device 14. The cradle 23 holds the winding bobbin 22 (paper tube, core tube, or the like) in a manner that the winding bobbin 22 can rotate. The winding drum 24 traverses the spun yarn 20 and drives the winding bobbin 22. The cradle 23 is swingable in a direction in which the cradle 23 approaches or moves away from the winding drum 24. Thus, the package 30 makes contact with or moves away from the winding drum 24. A spiral traverse groove 27 is formed in an outer peripheral surface of the winding drum 24. The traverse groove 27 allows the spun yarn 20 to be traversed.
The winding bobbin 22 is driven by driving and rotating the winding drum 24 located facing the winding bobbin 22. The winding drum 24 is coupled to an output shaft of a drum driving motor 53. Operation of the drum driving motor 53 is controlled by a motor control section (rotation speed control section) 54. This arrangement allows the spun yarn 20 unwound from the supplying bobbin 21 to be wound around the winding bobbin 22 at an appropriate speed.
A strain gauge 80 as a vibration detecting section is attached to the cradle 23. An attached position of the strain gauge 80 is not particularly limited. In the present embodiment, the strain gauge 80 is attached to one of the pair of cradle arms that hold the package 30. A signal (vibration intensity signal) of an output value from the strain gauge 80 is transmitted to the motor control section 54.
The motor control section 54 includes hardware such as a Central Processing Unit (CPU), a Random Access Memory (RAM), and a Read Only Memory (ROM), and programs stored in the ROM. The motor control section 54 can receive the vibration
intensity signal from the strain gauge 80 and transmit an operation control signal to the drum driving motor 53.
The motor control section 54 includes a comparison section 56, a speed increase section 57, and a speed reduction section 58. The comparison section 56 compares the vibration intensity signal with a predetermined intensity. The speed increase section 57 transmits a speed increase signal to the drum driving motor 53. The speed reduction section 58 transmits a speed reduction signal to the drum driving motor 53. Based on the result of the comparison by the comparison section 56, the motor control section 54 controls the speed increase section 57 to increase the speed of the drum driving motor 53 or controls the speed reduction section 58 to reduce the speed of the drum driving motor 53.
Next, the flow of control according to the present embodiment will be described with reference to Figure 2.
First, a new winding bobbin 22 (empty paper tube) is set on the cradle 23. Then, the spun yarn 20 is set on the winding bobbin 22 by a yarn setting means (not shown in the drawings). A winding operation is then started.
After the winding operation is started, a unit control section 50 transmits a signal to a motor control section 54 to increase the winding speed until the winding speed reaches a predetermined speed (touch winding set speed) that is lower than a normal winding speed (step S101).
Once the winding speed reaches the touch winding set speed, the touch winding control is started. Specifically, first, the comparison section 56 of the motor
control section 54 compares a value of the vibration intensity signal from the strain gauge 80 with a predetermined value (step S102). If the value of the vibration intensity signal is equal to or smaller than the predetermined value, the motor control section 54 determines that the rotation speed of the drum driving motor 53 can still be increased. The motor control section 54 thus carries out a process of increasing the rotation speed of the drum driving motor 53 (steps SI03 to S105). If the value of the vibration intensity signal is larger than the predetermined value, the motor control section 54 carries out a process of reducing the rotation speed of the drum driving motor 53 (steps S106 to S108) to set the value of the intensity of the vibration to be equal to or lower than the predetermined value.
Mien the predetermined value used for the comparison in the determination in step S102 is excessively large, the vibration of the cradle 23 may be intensified to damage the package 30 to degrade the quality of the package 30. In contrast, when the predetermined value is excessively small, the rotation speed of the drum driving motor 53 can only be increased slightly. This reduces the package productivity of the winder unit 10. Thus, in view of these circumstances, an appropriate value is preset as the predetermined value.
Steps S103 to S105 correspond to the process of increasing the winding rotation speed of the package 30 and thus to the function of the speed increase section 57. That is, if in the determination in step S102 (comparison by the comparison section 56), the value of the vibration intensity signal indicates a
value equal to or smaller than the predetermined value, a process of increasing the rotation speed of the drum driving motor 53 by a predetermined amount is repeated (steps S103 and S104) until the value of the vibration intensity signal indicates a value larger than the predetermined value. Once the value of the vibration intensity signal indicates a value larger than the predetermined value, the rotation speed of the drum driving motor 53 is reduced to the previous rotation speed (that is, the rotation speed at which the value of the vibration intensity signal indicates a value equal to or smaller than the predetermined value) (step S105). The speed increase process is then ended.
Steps S106 to S108 correspond to the process of reducing the winding rotation speed of the package 30 and thus to the function of the speed reduction section 58. That is, if in the determination in step S102 (comparison by the comparison section 56), the value of the vibration intensity signal indicates a value larger than the predetermined value, a process of reducing the rotation speed of the drum driving motor 53 by a predetermined amount is repeated (steps S106 and S107) until of the value of the vibration intensity signal indicates a value equal to or smaller than the predetermined value. Once the value of the vibration intensity signal indicates a value equal to or smaller than the predetermined value, the current rotation speed of the drum driving motor 53 is maintained (step S108). The speed reduction process is then ended.
Regardless of whether the speed increase process or the speed reduction process is carried out, after the speed increase process or the speed reduction
process has been completed, the motor control section 54 determines whether or not the winding operation is completed (step S109). In the determination process, the motor control section 54 determines whether or not a wound length measured since the start of winding of the yarn around the empty winding bobbin 22 has reached a predetermined length. A wound length equal to or greater than the predetermined length means that the package 30 is fully wound. In this case, a winding terminating process is carried out to terminate the flow. If the wound length is smaller than the predetermined length, the process returns to step S102 to continue the winding operation.
When the process returns to step S102, the motor control section 54 checks the intensity of the vibration again and compares the intensity with the predetermined intensity. According to the result of the comparison, the motor control section 54 carries out the speed increase process or the speed reduction process. In general, the rotation of the package 30 is gradually stabilized as the yarn is wound and the diameter of the package 30 increases. Thus, even for a winding speed that failed to be achieved previously as a result of value of the intensity of the vibration exceeding the predetermined value, if the winding speed is increased again after an increase in the package diameter, the value of the intensity of the vibration often remains equal to or smaller than the predetermined value. As a result, by repeating the processing from step S102 to step S109, the winding rotation speed can be gradually increased from the above-described touch winding set speed accompanying an increase in the winding diameter of the package
30. The loop from step S102 to step S109 can be carried out not only during what is called a touch winding period that is an initial period of the winding operation but also after the normal winding speed has been reached. The normal winding speed is a target winding speed input by an operator by operating an input device (not shown in the drawings) at the beginning of the winding operation.
Next, a second embodiment of the present invention will be described. Figure 3 shows a schematic diagram of a configuration of the winder unit 10 provided in an automatic wider according to the second embodiment. In the description below, the same arrangements as or arrangements similar to those in the first embodiment are denoted by the same reference numerals in the drawings. A description of these arrangements may be omitted.
The winding unit main body 16, provided in the winder unit 10 according to the present embodiment, includes the cradle 23, an arm type traverse device 11, and a contact roller 45. The cradle 23 rotatably holds the winding bobbin 22. The traverse device 11 traverses the spun yarn 20. The contact roller 45 can make contact with a peripheral surface of the winding bobbin 22 or the package 30 to rotate in conjunction with the rotation of the winding bobbin 22 or the package 30. The cradle 23 is pivotally movable around a pivotal shaft 46. Thus, an increase in yarn layer diameter resulting from the winding of the spun yarn 20 around the winding bobbin 22 can be absorbed by the pivotal movement of the cradle 23.
A package driving motor 55 is provided at the cradle 23. The winding bobbin
22 is rotationally driven by the package driving motor 55 to wind the spun yarn 20 into the package 30. Operation of the package driving motor 55 is controlled by the motor control section (rotation speed control section) 54.
An analog angle sensor 83 is attached to the pivotal shaft 46 to detect the angle (pivotal angle) of the cradle 23. The angle of the cradle 23 varies as the winding progresses and the winding diameter of the package 30 increases. Thus, the diameter of the yarn layer around the package 30 can be detected by detecting the pivotal angle of the cradle 23 by the angle sensor 83. Consequently, the spun yarn 20 can be properly traversed by controlling the traverse device 11 according to the package diameter. The angle sensor 83 is not limited to the analog sensor but may be a digital sensor or an absolute encoder.
In the present embodiment, the angle sensor 83 is also used as a vibration detecting section that detects vibration of the cradle 23. The angle sensor 83 transmits a detected angular signal to the comparison section 56 of the motor control section 54.
The traverse device 11 is provided in the vicinity of the contact roller 45. The traverse device 11 includes an elongate arm member 42, a hook-like traverse guide 41, and a traverse guide driving motor 43. The arm member 42 is swingable around a support shaft. The traverse guide 41 is formed at a tip of the arm member 42. The traverse guide driving motor 43 drives the arm member 42. The arm member 42 is reciprocated by the traverse guide driving motor 43 as shown by an arrow in Figure 3 to traverse the spun yarn 20. Operation of the traverse guide driving
motor 43 is controlled by the unit control section 50.
In the motor control section 54, the comparison section 56 compares the amplitude of a variation in the angular signals from the angle sensor 83 with a predetermined amplitude. Based on the result of the comparison, the motor control section 54 controls the speed increase section 57 to increase the rotation speed of the package driving motor 55 or controls the speed reduction section 58 to reduce the rotation speed of the package driving motor 55. The above-described arrangement allows the vibration of the cradle 23 to be deteced using the existing angle sensor 83.
The motor control section 54 includes a progression degree acquiring section 59 that acquires the degree of progression of the winding from the start of the winding of the spun yarn 20 around the empty winding bobbin 22. The progression degree acquiring section 59 receives, from the angle sensor 83, the angle of the cradle 23 moving pivotal ly accompanying an increase in the winding diameter of the package 30, to acquire the degree of progression of the winding.
Next, the flow of control according to the present embodiment will be described with reference to Figure 4.
When the winding operation is started, the unit control section 50 increases the winding speed until the winding speed reaches a predetermined speed (touch winding set speed) that is lower than the normal winding speed (step S201).
Once the winding speed reaches the touch winding set speed, the touch winding control is started. Specifically, first, the comparison section 56 of the motor
control section 54 compares the amplitude of a variation in the angular signals from the angle sensor 83 with the predetermined amplitude (step S202).
The angle sensor 83 inputs, for example, an analog voltage signal shown in Figure 5 to the comparison section 56. An upper graph in Figure 5 shows an example of the angular signals observed when the vibration of the cradle 23 is small. A lower graph in Figure 5 shows an example of the angular signals observed when the vibration of the cradle 23 is intense. Comparison between the upper and lower graphs clearly indicates that an intense vibration increases the amplitude A of the variation in the angular signal. Thus, by comparing the amplitude of the voltage signal from the angle sensor with the predetermined amplitude, a determination can be made as to whether or not the intensity of the vibration of the cradle 23 is equal to or lower than a predetermined value.
Steps S203 to S205 correspond to a process of increasing the winding rotation speed of the package 30. That is, if the motor control section 54 determines in step S202 that the amplitude of the angular signal is equal to smaller than the predetermined amplitude, the speed increase section 57 repeats a process of increasing the rotation speed of the package driving motor 55 by a predetermined amount until the amplitude of the angular signal becomes larger than the predetermined amplitude (steps S203 and S204). Mien the amplitude of the angular signal becomes larger than the predetermined value, the rotation speed of the package driving motor 55 is reduced to the previous rotation speed (step S205). The speed increase process is then ended.
On the other hand, if the motor control section 54 determines in step S202 that the amplitude of the angular signal is larger than the predetermined amplitude, the motor control section 54 determines whether or not the touch winding is completed (step S206). This determination is performed by monitoring the angular signal from the angle sensor 83 and detecting a state that the rotation angle of the cradle 23 has reached a predetermined angle or larger by the progression degree acquiring section 59. If the motor control section 54 determines in step S206 that the touch winding is not completed (that is, if a sufficient yarn layer has not been formed), the process of reducing the winding speed (steps S207 to S209) is carried out to settle the intensity of the vibration to be equal to or lower than a predetermined value. On the other hand, if the motor control section 54 determines that the touch winding is completed, a notif ing means (not shown in the drawings) such as a lamp or a buzzer is used to alarm the operator that the vibration is too intense (step S210). Then, the speed reduction process is skipped.
Steps S207 to S209 correspond to a process of reducing the winding rotation speed of the package 30. That is, if the motor control section 54 determines in step S202 that the amplitude of the angular signal is greater than the predetermined amplitude, a process of reducing the rotation speed of the package driving motor 55 by a predetermined amount is repeated until the amplitude of the angular signal becomes equal to or smaller than the predetermined amplitude (steps S207 and S208). When the amplitude of the angular signal becomes equal to or
smaller than the predetermined amplitude, the rotation speed of the package driving motor 55 is maintained (step S209). The speed reduction process is then completed.
According to the present embodiment, a determination is made as to whether or not the touch winding is completed (step S206) before the speed reduction process (steps S207 to S209). The speed reduction process is carried out only when the touch winding has not been completed. That is, during a period (touch winding period) after the winding start when the degree of progression of the winding is equal to or lower than a predetermined degree, the rotation of the package 30 may be unstable. Thus, both the speed increase process and the speed reduction process are carried out. After the touch winding period is over, a certain amount of yarn layer is formed and the vibration of the package 30 is stabilized. Thus, the speed reduction process is not carried out, and only the speed increase process is carried out. As described above, the speed reduction process is carried out only during the touch winding period. Thus, the yarn is prevented from being wound by slow winding speed not intended by the operator. Therefore, the package 30 can be wound with the winding speed increased up to the limit.
In the present embodiment, every time the speed increase process or the speed reduction process is completed, the yarn winding device stands by for a predetermined period of time with the current rotation speed of the package driving motor 55 maintained (step S211). The standby time is assumed to be, for example, about 5 seconds. The yarn winding device stands by because in the present
embodiment, since the rotational driving of the package 30 is independent of the traverse driving of the traverse device 11, certain amount of time is provided preferable to be to allow the traverse speed to follow a variation in the winding speed of the package 30.
When the predetermined standby time elapses, the motor control section 54 determines whether or not the winding operation is completed (step S212). If the motor control section 54 determines that the spun yarn 20 of a predetermined length has been wound, a process of terminating the winding operation is carried out to complete the flow. If the wound length is shorter than the predetermined length, the process returns to step S202 to continue the winding operation.
As described above, the winder unit 10 provided in the automatic winders according to the first and second embodiments includes the cradle 23, the strain gauge 80 or the angle sensor 83, and the motor control section 54. The cradle 23 rotatably supports the package 30. The strain gauge 80 or the angle sensor 83 detects the intensity of vibration of the cradle 23. The motor control section 54 controls the rotation speed of the package 30. The motor control section 54 allows the strain gauge 80 or the angle sensor 83 to monitor the vibration of the cradle 23 and controls the rotation speed of the package 30 according to the detected vibration intensity.
Thus, the rotation speed of the package 30 can be properly controlled with the vibration prevented from becoming excessive. As a result, the package productivity of the winder unit 10 can be improved.
The motor control section 54 includes the comparison section 56 and the speed increase section 57. The comparison section 56 compares the intensity of the vibration detected by the strain gauge 80 or the angle sensor 83 with the set intensity. The speed increase section 57 increases the rotation speed of the package 30 if the result of the comparison by the comparison section 56 indicates that the vibration intensity detected by the strain gauge 80 or the angle sensor 83 is equal to or lower than the set intensity.
Thus, the rotation speed of the package 30 can be increased within a range in which the vibration does not become excessive. In particular, the rotation speed of the package 30 can be quickly increased, with the package 30 prevented from flapping excessively during an increase in speed at winding start. Therefore, the package productivity can be improved.
In the yarn winding device, the motor control section 54 includes the speed reduction section 58. The speed reduction section 58 reduces the rotation speed of the package 30 if the result of the comparison by the comparison section 56 indicates that the vibration intensity detected by the strain gauge 80 or the angle sensor 83 is higher than the set intensity.
Thus, if excessive vibration occurs or is likely to occur, the rotation speed of the package 30 can be reduced to a speed at which the level of the vibration falls within a tolerable range, and the yarn winding device can continue the winding operation. As a result, tha package 30 can be prevented from being damaged due to vibration. Furthermore, this configuration allows the package productivity
of the winder unit 10 to be improved compared to a configuration that stops the winding when an abnormal vibration occurs.
The motor control section 54 includes the progression degree acquiring section 59. The progression degree acquiring section 59 acquires the degree of progression of winding from the start of winding of the package 30. The speed reduction section 58 reduces the rotation speed of the package 30 only if the winding progression degree acquired by the progression degree acquiring section 59 is equal to or lower than a predetermined progression degree.
Thus, at winding start when, for example, the eccentricity of the winding bobbin 22 of the package 30 is likely to cause excessive flapping, the speed reduction control can be performed to prevent the quality of the package 30 from being degraded by excessive vibration. That is, before the control for reducing the rotation speed of the package 30, the automatic winders according to the above-described embodiments acquire the degree of progression of the package winding from the start of winding of the package 30 to determine whether or not the touch winding, for which the rotation speed of the package 30 is set low, is completed. If the acquired winding progression degree is equal to or lower than a predetermined progression degree, that is, if the touch winding is not completed, the process of reducing the rotation speed of the package 30 is carried out according to the intensity of vibration of the cradle 23. As a result, the automatic winders according to the above-described embodiments can appropriately prevent the quality of the package 30 from being degraded by the excessive
vibration during the touch winding when the package is likely to flap.
After the winding progresses to a given degree and a sufficient yarn layer is formed on the package 30, that is, after the touch winding is completed, the process of reducing the rotation speed of the package 30 is not carried out because the yarn layer is expected to exert a vibration buffering effect. As a result, after the touch winding is completed, the spun yarn 20 is prevented from being wound by such slow rotation as not intended by an operator. Therefore, the package 30 can be wound with the winding speed increased up to the limit. This allows the package productivity of the automatic winder to be improved.
The automatic winder according to the first and second embodiments winds the spun yarn 20 by the method including a step of detecting the intensity of vibration of the cradle 23 that supports the rotating package 30 by the strain gauge 80 or the angle sensor 83, and a step of controlling the rotation speed of the package 30 according to the detected vibration intensity.
Thus, the rotation speed of the package 30 can be appropriately controlled with the vibration prevented from becoming excessive. As a result, the productivity can be improved.
The preferred embodiments of the present invention have been described. However, the above-described configurations may be changed as described below.
Instead of being configured as described above, the vibration detecting section may, for example, use an acceleration sensor to detect the vibration of the cradle 23 (or the package 30 held by the cradle 23). In this case, the
acceleration sensor is preferably provided at a tip portion of the cradle 23 at which acceleration is easily detected.
The attachment position of the vibration detecting section is not particularly limited. Instead of the arrangement in which the vibration detecting section is attached to the surface of the cradle 23, a vibration chip may be buried in the cradle 23 so as to detect the vibration of the cradle 23. Alternatively, provided that the vibration detecting section can detect the vibration of the cradle 23, the vibration detecting section can be installed, for example, in the winding unit main body 16. Specifically, the vibration chip may be mounted on a substrate provided in the unit control section 50 or the motor control section 54 of the winding unit main body 16. However, to allow a position close to the package 30 to be measured, the vibration detecting section is preferably placed near or on the cradle 23.
For detection of whether or not the intensity of vibration of the cradle 23 is equal to or lower than the predetermined value (within the tolerable range), instead of the arrangement in which the intensity of the vibration is compared with the predetermined value, for example, a frequency of the vibration intensity signal may be analyzed to compare a particular frequency component with a predetermined intensity.
The following operation is also possible: the process of reducing the rotation speed of the package 30 is carried out if the value of the intensity of vibration of the cradle 23 exceeds the predetermined value, whereas the process
of increasing the rotation speed of the package 30 is omitted if the value of the intensity of vibration of the cradle 23 is equal to or lower than the predetermined value. This arrangement omits the control that may result in an increase in the intensity of vibration of the cradle 23 (the control for increasing the rotation speed of the package 30) and is thus suitable particularly for forming a high-quality package 30.
The operator can appropriately set whether or not to carry out each of the speed increase and reduction processes or whether or not to carry out the speed reduction process after the touch winding is completed. This arrangement has an advantage of being capable of performing appropriate winding speed control according to circumstances.
The determination in step S206 in Figure 4 of whether or not the touch winding is completed need not necessarily be based on the measurement of the diameter of the yarn layer of the package 30 by the angle sensor 83. For example, the determination of the completion of the touch winding may be made when a predetermined time has elapsed since the start of the winding or when the wound yarn length has exceeded a predetermined length.
The operator can appropriately make a setting of the set intensity of vibration of the cradle 23 and conditions for completion of the touch winding. This arrangement is advantageous in that the conditions can be flexibly changed according to installation circumstances or the like of the automatic winder.
In the comparison process, the comparison section 56 may determine that the
intensity of the vibration of the cradle 23 detected by the vibration detecting section has exceeded the set intensity if the intensity of the vibration of the cradle 23 exceeds the set intesity for even a moment. Alternatively, the comparison section 56 may determine that the intensity of the vibration of the cradle 23 detected by the vibration detecting section has exceeded the set intensity if the intensity of the vibration of the cradle 23 continuously exceeds the set intensity for a predetermined period of time.
Even if the arm type traverse device 11 is used as in the case of the second embodiment, provided that the traverse device 11 is responsive enough that there is no delay in the traverse operation, the control for increasing and reducing the rotation speed of the package 30 may be performed without carrying out the standby process in step S211. Furthermore, even if the winding drum 24 is used to traverse the spun yarn 20 as in the case of the first embodiment, a predetermined standby time may be provided before the control for increasing and reducing the rotation speed of the package 30 is performed.
In the description of the second embodiment, the winder unit 10 includes the arm type traverse device 11, and the package driving motor 55 that rotationally drives the package 30. However, the winder unit 10 may be configured to traverse the spun yarn 20 using a belt type traverse device instead of the arm type traverse device 11. Furthermore, instead of the package driving motor 55, a driving motor that rotationally drives the contact roller 45 may be provided to rotationally drive the package 30 by driving and rotating the contact roller 45.
In the first and second embodiments, the unit control section 50 avoids performing the control for increasing and reducing the rotation speed of the package 30 according to the vibration of the cradle 23 until the touch winding set speed is reached. However, even during this period, the control for increasing and/or reducing the rotation speed of the package 30 may be performed. Furthermore, in this case, the period during which the speed increase and reduction control is performed may be appropriately selected.
In the first and second embodiments, the control for increasing the rotation speed of the package 30 may be performed even after the normal winding speed is reached. However, after the normal winding speed is reached, the control for increasing and reducing the rotation speed of the package 30 according to the intensity of vibration of the cradle 23 may be avoided, and the winding operation may be continued with the target winding speed maintained. Alternatively, the maximum winding speed of the automatic winder may be preset so that even after the normal winding speed is reached, the control for increasing and reducing the rotation speed of the package 30 according to the intensity of vibration of the cradle 23 is performed to the extent that the winding speed is kept equal to or lower than the maximum allowable winding speed.
The configurations of the above-described embodiments are not limited to the application to the automatic winder but are applicable to other yarn winding devices, for example, a spinning device.
While the present invention has been described with respect to preferred
' embodiments thereof, it will be apparent to those skilled in the art that the disclosed invention may be modified in numerous ways and may assume many embodiments other than those specifically set out and described above. Accordingly, it is intended by the appended claims to cover all modifications of the present invention that fall within the true spirit and scope of the invention.

We claim;
1. A yarn winding device comprising:
a cradle that rotatably supports a package;
a vibration detecting section that detects intensity of vibration of the cradle; and
a rotation speed control section that controls rotation speed of the package,
characterized in that the rotation speed control section allows the vibration detecting section to monitor vibration of the cradle, and controls the rotation speed of the package according to the detected vibration intensity.
2. The yarn winding device according to Claim 1, characterized in that the
rotation speed control section includes:
a comparison section that compares the vibration intensity detected by the vibration detecting section with a set intensity; and
a speed increase section that increases the rotation speed of the package if a result of the comparison by the comparison section indicates that the vibration intensity detected by the vibration detecting section is equal to or lower than the set intensity.
3. The yarn winding device according to Claim 2, characterized in that the
rotation speed control section includes a speed reduction section, and the speed
reduction section reduces the rotation speed of the package if the result of the
comparison by the comparison section indicates that the vibration intensity detected by the vibration detecting section is higher than the set intensity.
4. The yarn winding device according to Claim 3, characterized in that the
rotation speed control section includes a winding progression degree acquiring
section that acquires winding progression degree of winding of the package from
start of the winding, and
the speed reduction section reduces the rotation speed of the package only if the winding progression degree acquired by the winding progression degree acquiring section is equal to or lower than a predetermined winding progression degree.
5. A yarn winding method characterized by comprising:
a step of detecting intensity of vibration of a cradle that supports a rotating package; and
a step of controlling rotation speed of the package according to the detected vibration intensity.