JPH11181636A - End breakage detection of spinning machine and end breakage detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate detection of yarn breakage to each spindle even when there is a spindle in which wound amount is different from that of other spindle by occurrence of yarn breakage in a spinning machine independently driving each spindle by a motor fixed to every each spindle. SOLUTION: A current sensor 7 and a current measuring device for measuring electric current fed to a spindle motor 2 are set on every each spindle. Each current measuring device 8 is connected through a communication line 10 and a section control unit 9 to a main controller 11. The main controller 11 inputs current value fed to each spindle in a prescribed frequency from the current measuring device 8 and operates average value of current value data of spindle free from end breakage history from starting of machine frame. Then, the spindle is judged to be end breakage when deviation of current value of each spindle from the above average value. A spindle not having yarn breakage history is discriminated from a spindle having yarn breakage history until yarn breakage is judged and judgment of yarn breakage is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yarn breakage detecting method and a yarn breakage detecting device in a spinning machine such as a ring spinning machine or a ring twisting machine which independently drives a spindle of each spindle by a motor provided for each spindle. Things.

[0002]

2. Description of the Related Art When a yarn break occurs during spinning, it is desirable to detect the yarn break reliably and early in order to quickly repair the yarn break. Therefore, the spinning machine is provided with a yarn breakage detecting device. On the other hand, in recent years, in order to increase the number of spindles of the spinning frame, increase the spindle rotation speed, reduce noise, and save energy, etc., instead of driving all the spindles of the spinning frame with one motor, each spindle has its own weight. An apparatus provided with a motor for driving a spindle has been proposed. Then, a thread breakage detection method has been proposed which utilizes the characteristics of a device for driving a spindle by a separate motor for each weight.

For example, Japanese Patent Application Laid-Open No. Hei 6-57560 discloses a method in which a current sensor for measuring a current supplied to a motor provided in each weight is provided, and a current change rate is obtained from the output of the current sensor. There is disclosed a method of determining that a thread break has occurred when a value is exceeded.

Japanese Patent Application Laid-Open No. Hei 9-13235 has started a ring spinning frame drive system as shown in FIG. In this system, an inverter 52 is provided for each drive motor 51 of the spindle of each weight.
2 is connected to a DC power supply network 54 via a conductor 53. The DC power supply network 54 is powered from only one rectifier 55. Each inverter 52 has a control lead 56
And a common conducting wire 57 and a motor control mechanism 58.
Is controlled to be rotated at a desired rotation speed. Conductor 5
A measuring unit 59 for detecting a current supplied to each inverter 52 is connected to 3. Each measurement unit 59
Is connected to the evaluation unit 60. Then, the evaluation unit 60 obtains a difference between the average output of each inverter 52 and the output of each inverter 52, and determines that the yarn is broken when the value is equal to or more than a predetermined amount.

[0005]

Problems to be Solved by the Invention
In the device disclosed in Japanese Patent Laid-Open Publication No. H06-27139, it is determined that the yarn breaks when the rate of change of the current is large, and when the thread breaks during doffing, the current change rate is large since the thread breaks from the restart point. There is no change, and no yarn break can be detected. Further, immediately after the start of the spindle motor, there is a problem that the torque fluctuation of the motor is large, and it is difficult to distinguish between the current change rate due to the torque fluctuation and the current change rate due to the yarn breakage.

On the other hand, according to the method disclosed in Japanese Patent Application Laid-Open No. Hei 9-13235, when the difference between the average value of the output of the inverter 52 of all weights and the output of the inverter 52 of each weight is shifted by a predetermined value or more, the yarn breakage occurs. Thus, it is possible to detect a broken thread even if the weight has a broken thread during doffing. However, in a ring spinning machine or the like, since the yarn is wound on a bobbin on the spindle, the load applied to the spindle driving motor changes with the lapse of time from the start of winding. In addition, the ring rail repeatedly moves up and down at the time of winding, and the balloon shape of the yarn from the snell wire to the traveler differs depending on the position of the ring rail, thereby changing the load. Then, the weight in which the yarn breakage occurred during winding has a smaller winding amount than other weights, and the load applied to the driving motor also becomes smaller. Therefore, in the method disclosed in Japanese Patent Application Laid-Open No. 9-13235, in which the weight simply deviating from the average value is determined to be a thread breakage weight, it takes a long time to repair due to thread breakage and the winding amount is different. There is a problem that erroneous detection of a thread break increases for the changed weight.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a spinning machine that independently drives a spindle of each spindle by a motor provided for each spindle.
Provided is a yarn breakage detection method and a yarn breakage detection device for a spinning machine that can accurately detect the presence or absence of a yarn breakage for each weight even if there is a weight whose winding amount is different from other weights due to the occurrence of a yarn breakage. Is to do.

[0008]

In order to achieve the above object, in the yarn breakage detecting method according to the present invention, a plurality of weights are provided and a spindle for each weight is provided for each weight. In a spinning machine driven independently by a motor,
The current supplied to the motor of each weight for the same weight with no thread break history from the machine start-up to the thread break detection time by distinguishing between weights with thread break history and weights without thread break history The values are simultaneously detected at a predetermined time, the average value is obtained, the presence / absence of thread breakage is determined based on the average value and the current value of each weight, and the winding amount is determined by the history of thread breakage from other weights. The reduced weight determines the presence / absence of a thread break based on the average value of the weight having no history of thread breakage corresponding to the winding amount at the time of detection of thread breakage of the weight and the current value of the weight based on the average value of the weight. I do.

According to a second aspect of the present invention, in a spinning machine equipped with a large number of weights and independently driving spindles of each weight by a motor provided for each weight, a main control unit for controlling all weights is provided. A current detecting means provided for each weight and measuring a current supplied to the motor of each weight; and an output of the current detecting means for the weight provided for each weight determined based on a command from the main control unit. At the same time, the sub-control unit that transmits the measurement data as digital current value data to the main control unit, and calculates the average value of the current value data of the weight that has no thread breakage history from the start of the machine base. Arithmetic means;
First judging means for judging the presence or absence of thread breakage of each weight having no history of thread breakage based on the average value and the current value data of each weight, and a current value used at the time of judgment by the first judging means Storage means for sequentially storing the average value of the data together with the corresponding winding amount, current value data of a weight having a thread breakage history,
A second judging means for judging the presence or absence of thread breakage of the weight based on an average value for a winding amount equal to the winding amount of the weight at the time of measuring the current value data obtained from the data stored in the storage means; And with.

According to a third aspect of the present invention, in the second aspect of the present invention, the second determining means determines the current value data and the current value of the weight for the weight determined to be broken at the time of the previous yarn break determination. It is determined whether or not the weight has been spliced based on the winding amount of the weight at the time of measuring the current value data obtained from the data stored in the storage means and the average value for the winding amount.

According to a fourth aspect of the present invention, in the second or third aspect of the present invention, the entire weight is divided into a plurality of groups, and the sub-control unit is provided with a first sub-unit provided for each of the weights. A control unit; and a second sub-control unit that is provided for each group and relays a signal between the first sub-control unit and the main control unit.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the first determining means calculates an average value and a standard deviation from a current value of each weight. At the same time, a weight whose current value data deviates from the average value by a predetermined ratio or more of the standard deviation is determined as a thread break.

In the invention according to claim 6, in the invention according to any one of claims 2 to 5, the second judging means performs a correction based on a difference between a winding amount and a spindle rotation speed. The thread breakage is determined using the current value.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the two judging means judge a thread break other than at the time of starting and stopping. According to the first aspect of the present invention, the spindle of each weight is independently driven by a motor provided for each weight.
The detection of a thread break is performed by distinguishing a weight having a history of thread break and a weight having no history of a thread break from the start of the machine stand to the timing of detecting the thread break. With respect to the same weight of the winding having no thread breakage history, the current value supplied to the motor of each weight is detected at a predetermined time at the same time, and the average value is obtained, and the average value and the current value of each weight are calculated. The presence or absence of a thread break is determined based on. In addition, for a weight whose winding amount has become smaller than a weight having no history of yarn breakage due to the history of yarn breakage, the average of the weights having the same winding amount in the weight having no history of yarn breakage corresponding to the winding amount at the time of detecting the yarn breakage of the weight. The presence or absence of thread breakage is determined based on the value and the current value of the weight.

According to the second aspect of the present invention, the spindle of each weight is independently driven by a motor provided for each weight. The current supplied to the motor of each weight is measured by current detection means provided for each weight. The output of the current detecting means is input to the sub control unit at a predetermined time based on a command from the main control unit, and the measurement data is transmitted to the main control unit as digital current value data. The average value of the current value data of the weight having no history of thread breakage from the start of the machine base is calculated by the calculation means. Then, the first judging means judges the presence or absence of thread breakage of each weight having no history of thread breakage based on the average value and the current value data of each weight. The average value of the current value data used at the time of the judgment by the first judgment means is sequentially stored in the storage means together with the corresponding winding amount. In the second determining means, the current value data of the weight having a history of thread breakage and the winding amount equal to the winding amount of the weight at the time of measuring the current value data obtained from the data stored in the storage means are described. The presence or absence of thread breakage of the weight is determined based on the average value.

According to a third aspect of the present invention, in the second aspect of the present invention, for the weight determined to be broken at the time of the previous yarn break determination, the second determining means performs splicing with the weight. It is determined whether it has been performed. This determination is made based on the current value data of the weight and the average value of the winding amount equal to the winding amount of the weight when measuring the current value data obtained from the data stored in the storage means.

According to a fourth aspect of the present invention, in the second or third aspect, the entire weight is divided into a plurality of groups, and a first sub-control unit provided for each weight and a main control unit are provided. The transmission and reception of the signal with the unit is relayed by the second sub-control unit.

According to a fifth aspect of the present invention, in the invention according to any one of the second to fourth aspects, the average value and the standard deviation of the current value of each weight are calculated by the first determining means. Is done. A weight whose current value data deviates from the average value by a predetermined ratio or more of the standard deviation is determined to be a thread break.

In the invention according to claim 6, in the invention according to any one of claims 2 to 5, when the thread breakage of the weight whose winding amount is reduced due to the history of thread breakage is detected, the second thread is detected. The current value corrected by the difference between the winding amount and the spindle speed by the determining means is used.

According to a seventh aspect of the present invention, in any one of the second to sixth aspects of the present invention, the yarn breakage determination is performed by the two determination means except at the time of starting or stopping.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is embodied in a ring spinning machine will be described below with reference to FIGS.
As shown in FIG. 1A, each spindle 1 of the spinning machine is provided with a spindle driving motor (hereinafter referred to as a spindle motor) 2. As the spindle motor 2, a three-phase induction motor is used.
Are connected to a power supply line 4 connected to a common motor driving device 3 via a power supply line 5. A large number of spindle motors 2 (only one is shown) are connected to the power supply line 4 in parallel. The ring rail 6 and the draft part drive system (not shown) are driven by a motor (not shown) different from the spindle motor 2.

A current sensor 7 as current detecting means for measuring a current supplied to each spindle motor 2 is provided on an arbitrary one of the three power supply lines 5 of each weight. The current sensor 7 is preferably a current transformer type sensor, a Hall element type sensor or the like, but may be a current shunt type sensor. The current sensor 7 is connected to a current measuring device 8 as a first sub control unit. The current measuring device 8 appropriately amplifies the output voltage signal of the current sensor 7 (in the case of a current transformer type sensor, a voltage signal after current / voltage conversion), and a low-pass filter that processes the amplified signal (both are used). (Not shown)). Further, the current measuring device 8 includes a microcomputer, and can always take in the processed signal of the low-pass filter as digital data via an A / D converter (both are not shown).

The power supply line 5 is provided with a normally closed contact (not shown) of a relay for each weight, the relay is excited based on a thread break signal, the normally closed contact opens, and the weight of the weight is reduced. The power supply to the spindle motor 2 is stopped.

The entire weight is divided into a plurality of groups, and FIG.
As shown in (b), the current measuring device 8 sets a plurality of weights (for example, 48 weights) as one group, and sends the communication line 1 to the section control unit 9 as a second sub-control unit.
0. Each section control unit 9 is connected via a communication line 10 to a main control device 11 as a main control unit for controlling all weights. Communication line 1
For 0, a multi-drop connection using the serial interface 12 is adopted. For example, RS-485 is used as the serial interface 12.

Each current measuring device 8 and each section control unit 9 input the output of the current sensor 7 provided for each weight at a predetermined time on the basis of a command from the main control device 11, and the measured data is input. A sub-control unit that transmits digital current value data to the main control device 11 is configured. Each section control unit 9 relays transmission and reception of signals between the current measurement devices 8 of the group connected to the section control unit 9 and the main control device 11.

As shown in FIG. 1B, the main controller 11
Is provided with a central processing unit (hereinafter, referred to as a CPU) 13 as a calculating means, a first determining means, and a second determining means. The main controller 11 includes a program memory 14, a working memory 15 as a storage unit, an input device 16, and an input / output interface 17. The CPU 13 is connected to a winding amount detecting means 18 via an input / output interface 17. A counter that accumulates the number of rotations of a front roller (not shown) is used as the winding amount detecting unit 18.
3 calculates the winding amount at that time from the count value.

The program memory 14 is a read-only memory (ROM), and stores program data and various data necessary for executing the program data. The program data includes various fiber raw materials, spun yarn counts, number of twists, and other spinning conditions, as well as data on the correspondence between the spindle rotation speed during steady operation, the rotation speed of the draft drive system and the lifting drive system motor, and various other data. There is a map or the like showing the relationship between the number of rotations and the amount of supply current at the winding amount of. This map differs depending on the spinning conditions, and is obtained by performing a spinning test in advance or theoretically. The work memory 15 is a readable and rewritable memory (RAM), and temporarily stores data input by the input device 16, calculation results of the CPU 13, and the like.

The CPU 13 calculates the average value and the standard deviation of the current value data of the weights having no history of yarn breakage from the start of the machine, and based on the average value and the current value data of each weight, there is no history of yarn breakage. It is determined whether or not each weight has a broken thread. CPU1
No. 3 determines that a thread break has occurred when the difference between the average value and the current value data of each weight is greater than a plurality of times (three times in this embodiment) the standard deviation. At this time, the CPU 13 functions as a first determination unit. The CPU 13 performs the thread break determination at a predetermined cycle (for example, several tens of milliseconds), and stores the average value and the standard deviation at that time together with the corresponding winding amount in the working memory 15 sequentially. However, the thread breakage detection is not performed at the time of starting and stopping when the torque fluctuation of the spindle motor 2 is large.

The working memory 15 is provided with a storage area for storing the amount of winding corresponding to each weight. The amount of winding that should have been performed is calculated and stored in the storage area of the working memory 15. The CPU 13 determines the current value data of the weight having a yarn breakage history and the winding amount equal to the winding amount of the weight at the time of measuring the current value data obtained from the data stored in the storage means and the winding amount from the start of winding. The presence or absence of thread breakage of the weight is determined based on the average value and the standard deviation. At this time, the CPU 13 functions as a second determining unit.

When judging a thread breakage in a spindle having a history of thread breakage, the CPU 13 corrects the difference between the winding amount and the spindle speed at the time of detecting the current of the weight and the spindle speed of the average value at the winding amount. The yarn breakage is determined using the current value subjected to the above.

Next, the operation of the above-configured apparatus will be described. Prior to the operation of the spinning machine, spinning conditions such as a fiber material, a spun yarn count, and a number of twists are input by the input device 16. When the operation of the spinning machine is started, the CPU 13 of the main control device 11 outputs a speed command signal to each motor drive device 3 based on the input spinning conditions. The motor drive device 3 controls each spindle motor 2 so as to have a predetermined rotation speed corresponding to a command signal from the main control device 11. Further, the draft part drive system and the lifting drive system are also driven at a predetermined rotation speed ratio with respect to the spindle 1 based on a command signal from the main controller 11.

As shown in FIG. 4, for example, the drive of the spindle 1 is accelerated rapidly at the time of starting, then gradually increased in speed, and suddenly decelerated near the full tube, and then stopped. You. When the spinning machine is started, the current value changes every moment due to sudden acceleration, the torque fluctuation of the spindle motor 2 is large, and an error is likely to occur in the thread breakage determination. During this time, most of the weights are normally wound, but some of the weights may be broken.
Further, at the time of deceleration for stopping, the current value changes every moment due to rapid deceleration, and an error is likely to occur in the thread breakage determination. Therefore, the presence or absence of the thread breakage weight is not determined.

After the sudden acceleration is completed, the CPU 13 performs the yarn break detection determination at a predetermined cycle until the deceleration for stopping is started. The thread breakage detection judgment is the weight where the thread breakage occurred from the beginning of winding to the time of the thread breakage detection judgment (weight with a history of thread breakage)
And the weight without thread breakage (weight without history of thread breakage)
Is performed separately.

Until the thread breakage weight is detected, the CPU 13 performs the thread break detection determination according to the flowchart shown in FIG. First, the CPU 13 instructs each spindle to read a current value in step S1, and stores the spinning amount (winding amount) at that time in the working memory 15. And
A command to read an output signal from the current sensor 7 is simultaneously output from the CPU 13 to each section control unit 9. When each section control unit 9 receives the signal, the section control unit 9 simultaneously outputs a reading command of an output signal from the current sensor 7 to each current measuring device 8. Each current measuring device 8 reads and holds the output of the current sensor 7 at that time according to the command. Each current measuring device 8 processes the output signal of the current sensor 7 and holds it as digital data. Communication speed via serial interface 12 is 10k
bit / sec or more, the detection data read by each current measuring device 8 can be regarded as being read at substantially the same time, and changes due to the elevation of the ring rail 6 during the time required for communication control. And is substantially unaffected by the current. The digital data held in each current measuring device 8 is stored until the current value is read and digital processing is performed next, and then updated to the next digital data.

Next, in step S 2, the CPU 13 outputs a transmission command of the read current value data to each current measuring device 8 via each section control unit 9. Then, the current value data of each current measuring device 8 is input to the CPU 13 via the respective section control units 9. At the time of the first judgment from the start of the machine stand, the current value is distributed to the weight corresponding to the successfully wound (normal weight) as shown in FIG. Divided into the corresponding distribution. Each distribution can be treated almost as a normal distribution. Next, the CPU 13 determines the average value << x >> of the current value data of each weight successfully wound in step S3 and the standard deviation σ
Is calculated, and those values are stored in the working memory 15 together with the spinning amount.

Next, in step S4, it is determined whether or not I <<< x >>-3σ, that is, whether or not the difference between the average value << x >> and the current value data I of each weight is greater than three times the standard deviation σ. Are determined in order from the smallest numbered weight. If the difference is greater than three times the standard deviation σ, the CPU 13 determines that the weight is a thread break weight, and proceeds to step S5. In step S5, it is determined that the weight is a thread break weight. Is stored in a predetermined storage area of the working memory 15. Also, CP
U13 outputs a thread break signal of the weight. Step S4
If NO in step S6, the process proceeds to step S6. Next, in step S6, the CPU 13 determines whether or not the thread breakage determination has been performed for all the weights. If the determination is NO, the process returns to step S4 to perform the same determination for the next weight. If the answer is YES in step S6, the thread break determination operation ends. Thereafter, the same operation is repeated at a predetermined cycle until a thread breakage weight occurs.

Since the thread breakage weight is not wound until the thread break is repaired by the splicing operation, there is no guarantee that the current value returns to the same value as the weight that has been wound without thread breakage from the beginning of winding. . Therefore, after a thread break occurs, the CPU 13 determines the thread break according to the flowchart shown in FIG. 6 for the weight having a history of thread break, and determines the thread break according to the flowchart shown in FIG. 5 for the weight without the history of thread break. Do.

For the weight determined to be a thread break, the current winding amount (spinning length) is stored in the work memory 15, and the CPU 13 determines the next thread break determination cycle (at the time of the thread break determination).
If the current value of the weight does not satisfy the criterion I <<< x >> − 3σ at the time of thread breakage, it is determined that the thread has been spliced. Thereafter, the CPU 13 separately manages the winding amount of the weight.

Next, a description will be given of the determination of thread breakage of a weight having a thread breakage history according to the flowchart of FIG. This operation is performed subsequently after the operation according to the flowchart of FIG. 5 is completed. The CPU 13 determines in step S11 whether or not there is a weight determined to be thread broken at the time of the previous thread break determination. If there is a weight determined to be thread broken, the CPU 13 proceeds to step S12.
Then, it is determined whether or not the yarn breakage weight has been sequentially spliced in ascending order of the weight number. That is, the current value I
Is compared with the previous determination reference value << x >>-3σ,
If I <<< x >> − 3σ is not satisfied, it is determined that piecing has been performed, and the process proceeds to step S13, where the CPU 13 calculates the winding amount that should have been wound during the yarn breakage on the weight.
It is stored in the storage area of the working memory 15. If the winding amount has been stored in the storage area before, the value added to the value is stored, and then the process proceeds to step S14. CPU
13 satisfies I <<< x >> − 3σ, it is determined that the thread break is continuing, and the process proceeds to step S14.

In step S14, step S12 is executed for all the weights determined to be broken at the time of the previous yarn break determination.
Is determined. If the determination is no, the process returns to step 12 to perform the same processing as described above for the next weight that has not been determined. If the determination is yes, the process proceeds to step S15. If there is no thread breakage weight at the time of the previous thread breakage determination in step S11, step S1
Go to 5.

In step S15, the CPU 13 makes a thread breakage determination for a spindle having a history of thread breakage that was not previously determined to be a thread breakage. The yarn breakage is determined by the current value I
And the average value << x >> and the standard deviation σ corresponding to the current winding amount of the weight satisfy I <<< x >> − 3σ. If I <<< x >> − 3σ is satisfied, it is determined that a thread break has occurred, and the flow advances to step S16 to determine that the weight is a thread break weight and the winding amount of the weight at that time. And outputs a thread breakage signal of the weight. The winding amount is calculated from the difference between the winding amount from the beginning of the winding at the time of reading the current value and the winding amount of the weight stored in the working memory 15 during thread breakage.

If I <<< x >> − 3σ is not satisfied in step S16, the CPU 13 determines that there is no thread breakage and proceeds to step S17. Then, in step S17, step S17 is executed.
It is determined whether or not the determination has been made for all the weights that need to be determined in step 15. If NO, the process returns to step S15, and the same processing as described above is performed for the next weight for which no determination has been made. If yes, the current thread break determination processing ends.

The current value supplied to the spindle motor 2 is proportional to the load torque applied to the spindle motor 2, and the load torque is proportional to the spinning length (winding amount). Further, as shown in FIG. 3, even with the same winding amount, the windage changes according to the rotation speed, the torque changes, and the current supplied to the spindle motor 2 also changes. The rotation speed of the spindle 1 is changed a plurality of times, for example, as shown in FIG. And, in the case of using the average value with the same winding amount, for the weight whose winding amount is smaller than that of the weight with no history of yarn breaking due to yarn breakage,
In many cases, the rotation speeds are different, and if an average value is simply used for the same winding amount, an error increases. Therefore, in this embodiment, the CPU 13 determines the yarn breakage by using the current value after the correction based on the difference in the winding amount and the spindle speed in the current value to be compared in step S15.

The normally-closed contact of the relay provided on the power supply line 5 opens the weight to which the thread breakage detection signal is output from the CPU 13, and the power supply of the weight to the spindle motor 2 is stopped. . When the piecing operation is performed by the operator or the piecing device, the normally closed contact is closed and the spindle motor 2 is driven.

This embodiment has the following effects. (B) The thread breakage judgment is made by distinguishing between the weight in which the thread breakage has occurred and the weight in which no thread breakage has occurred between the start of the machine stand and the time of the thread breakage detection, and the current value of each weight has the thread breakage. The determination is performed based on the deviation from the average value of the current value at the time of determining the breakage of the weight of the weight having no history. Therefore, even if there is a weight whose winding amount is different from that of a weight having no history of yarn breakage due to the occurrence of a yarn breakage, the presence or absence of a yarn breakage can be accurately detected for each weight.

(B) Since the main controller 11 monitors the presence or absence of thread breakage in all the spindles, it is easy to construct a monitoring system using the information. (C) A determination as to whether or not piecing has been performed on the weight determined to be broken at the time of the previous yarn break determination is performed based on the average value and the standard deviation of the current used for the yarn break determination. Therefore, it is not necessary to provide a means (for example, a switch) for informing the thread breakage repair that is turned on when the piecing operation is completed for each weight.

(D) All weights are divided into a plurality of groups, and transmission and reception of signals between each current measuring device 8 and main control device 11 provided for each weight are provided for each group. Since the data is relayed by the section control unit 9, it is easy to synchronize the data sampling timing of the multiple spindles. Further, the load on the communication means is reduced as compared with the case where each current measuring device 8 and the main control device 11 are directly connected by the communication means without providing the section control unit 9.

(E) The reference value for the thread breakage determination is automatically set to an appropriate value based on the average value and the standard deviation of the current values of the respective weights. There is no need to input a predetermined value, and an appropriate yarn breakage determination is automatically performed regardless of the spinning conditions. The value of the current value I of the thread break weight is 10 to 2
Variation between weights that is about 0% smaller and is not broken (1-2
%), It is possible to reliably determine the thread breakage weight.

(F) When detecting a thread breakage of a weight with a history of thread breakage and a reduced winding amount, the current value corrected by the difference in the winding amount and the spindle rotation speed is used, so that the thread breakage is accurately performed. The presence / absence determination is performed.

(G) Since the thread breakage is determined at times other than the start and stop, the risk of erroneous detection is reduced. (H) The thread break can be detected immediately except at the time of start / stop, and the drive of the spindle motor 2 of the spindle is stopped by the thread break signal, and the spindle 1 stops. Therefore, it is possible to prevent the adjacent weight from being broken due to the continued rotation of the spindle 1 after the occurrence of the yarn breakage. In addition, the generation of fluff due to the bobbin of the thread breaker being rotated for a long time is reliably prevented.

The embodiment is not limited to the above, and may be embodied as follows, for example. As shown in FIG. 7, the motor driving device 3 is provided for each weight, and a current sensor 7 or a current detection circuit is provided in the motor driving device 3 as current detecting means. The motor driving device 3 includes an inverter that converts a DC power supply into an AC power supply. Then, the function of the current measuring device 8 of the embodiment is also provided to the motor driving device 3. In this embodiment, a spindle drive command from the main control device 11 is also transmitted to the motor drive device 3 of each weight via the section control unit 9. Accordingly, by employing a configuration in which the motor driving device 3 of the weight stops driving the spindle motor 2 in response to the yarn breakage signal, it is not necessary to provide a relay and a normally closed contact for each weight.

When judging the thread breakage weight, instead of comparing with the current value of each weight based on the difference between the average value “x” and three times the standard deviation σ, a predetermined ratio of the standard deviation σ (for example, , 2 times). Further, the thread breakage may be determined when the current value of each weight deviates from the average value “x” by a predetermined ratio (for example, 10%) or more without using the standard deviation σ. Also in this case, it is not necessary to input a predetermined value in advance to determine the presence or absence of a thread breakage weight.

The main controller 11 and each current measuring device 8 may be connected by the communication line 10 and the serial interface 12 without providing the section control unit 9. ○ Instead of the main controller 11 determining whether or not a thread breakage weight has been calculated, the main controller 11 calculates the average value and the standard deviation, and transmits those values to each current measuring device 8 to measure the current. The device 8 may be configured to perform the yarn break determination.
In this case, it is possible to reduce the time required to complete the thread breakage determination for all the weights.

When calculating the average value and the standard deviation, instead of obtaining the average value and the standard deviation of the current values of the weights that are not broken, instead of calculating the average value and the standard deviation from the start of the machine stand to the previous time of the yarn break determination, there is no history of the yarn break history. Find the average value and standard deviation of the weight. In this case, the average value and the standard deviation can be calculated more easily without checking the distribution of the current value data taken in at the time of the yarn breakage determination.

Instead of making a determination as to whether or not piecing has been performed with the weight determined to have been broken at the time of the previous yarn breakage determination based on the average value and the standard deviation of the current values, The determination may be made based on an ON signal of a thread breakage repair switch provided at each of the weights that are turned ON.

The connection between the main control device 11 and the section control unit 9 and the connection between the section control unit 9 and the current measuring device 8 may be made by a method other than the multi-drop connection. Further, wireless communication may be used as the communication means.

The yarn breakage detection may be performed when the machine base is started or stopped. A configuration may be adopted in which the calculation of the winding amount of the weight having a yarn breakage history is performed by the current measuring device 8 provided for each weight. For example, at the time of yarn breakage and at the time of yarn breakage repair, the integrated data of the winding amount detecting means 18 is input via the main controller, and the winding amount from the start is calculated based on the input value. In this case, as compared with the case where the main controller 11 calculates the winding amount of each of the weights having a history of yarn breakage, the time until the series of yarn breakage determination processing shown in FIG. 6 is completed can be reduced.

The present invention is not limited to the ring spinning machine, but may be applied to a single spindle drive type ring twisting machine or the like. The technical ideas (inventions) other than those described in the claims that can be understood from the above embodiments will be described below together with their effects.

(1) In the invention as set forth in any one of claims 2 to 7, the first and second judging means are provided for each of the weights, and an average value and the like required for the judgment are provided. Is obtained from the main control unit via the communication means.
In this case, it is possible to reduce the time required to complete the thread breakage determination for all the weights.

[0060]

As described in detail above, according to the first to seventh aspects of the present invention, in a spinning machine in which the spindle of each weight is independently driven by a motor provided for each weight, Even if there is a weight whose winding amount is different from that of another weight due to the occurrence of a break, the presence or absence of a yarn break can be accurately detected for each weight.

According to the third aspect of the present invention, it is determined whether or not piecing has been performed for the weights determined to be broken at the time of the previous yarn breakage determination upon completion of the piecing operation for each weight. This can be easily performed without providing a thread breakage repair switch that is turned on.

According to the fourth aspect of the present invention, it is easy to synchronize the data sampling timing of the multiple spindles, and the communication can be reduced. According to the fifth aspect of the present invention, it is not necessary to input a predetermined value in advance for the presence / absence of a thread breakage weight by the first determination means, and an appropriate thread breakage is automatically performed regardless of spinning conditions. The presence / absence determination is performed.

According to the sixth aspect of the present invention, the presence / absence of thread breakage of the weight whose winding amount has been reduced due to thread breakage can be more accurately determined. According to the invention described in claim 7,
Since the presence / absence of yarn breakage is determined at times other than the start and stop, erroneous determination hardly occurs.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram illustrating one embodiment.

FIG. 2 is a graph showing a distribution of a current value.

FIG. 3 is a graph showing a relationship between a spindle rotation speed and a current value at the same winding amount.

FIG. 4 is a graph showing a change in spindle speed from the start of winding to the stop of full filling.

FIG. 5 is a flowchart showing a thread break determination procedure.

FIG. 6 is a flowchart showing a thread break determination procedure.

FIG. 7 is a block circuit diagram of another embodiment.

FIG. 8 is a block circuit diagram of a conventional device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Spindle, 2 ... Spindle motor, 7 ... Current sensor as current detection means, 8 ... First constituting a sub control unit
A current measuring device as a sub-control unit, 9... A section control unit as a second sub-control unit constituting the sub-control unit,
11: a main controller as a main controller, 13: arithmetic means,
A CPU as a first determining unit and a second determining unit,
5. Working memory as storage means.

Claims (7)

[Claims] 1. A spinning machine equipped with a large number of weights and independently driving a spindle of each weight by a motor provided for each weight. Certain weights and weights with no history of thread breakage are distinguished from each other, and the current value supplied to the motor of each weight is simultaneously determined at a predetermined time for the same weight of winding with no history of thread breakage, and the average value is calculated. The weight that is determined based on the average value and the current value of each weight to determine the presence or absence of thread breakage, and the amount of winding is smaller than the other weights due to the history of thread breakage is the winding amount at the time of yarn breakage detection of the weight. A thread breakage detecting method for a spinning machine, which determines whether or not there is a thread break based on an average value of the weight having no history of yarn breakage and a current value of the weight. 2. A spinning machine equipped with a large number of weights and independently driving spindles of the respective weights by motors provided for the respective weights, a main control section for controlling all the weights, and a spinning machine provided for each weight. Current detection means for measuring the current supplied to the motor of each weight, and the output of the current detection means of the weight provided for each weight is input at a predetermined time based on a command from the main control unit, and A sub-control unit for transmitting measurement data as digital current value data to the main control unit; a calculating means for calculating an average value of the current value data of the weight having no history of thread breakage since the start of the machine; and the average value First judging means for judging the presence or absence of yarn breakage of each weight having no yarn breakage history based on the current value data of each weight, and an average of current value data used at the time of judgment by the first judging means. Value with the corresponding winding A current value data of a weight having a history of thread breakage, and an average for a winding amount equal to the winding amount of the weight when measuring the current value data obtained from the data stored in the storage means. And a second judging means for judging the presence or absence of thread breakage of the weight based on the value. 3. The method according to claim 2, wherein the second determining means determines, for the weight determined to be broken at the time of the previous yarn breaking determination, the current value data of the weight and the current value data obtained from the data stored in the storage means. 3. The yarn breakage detecting device for a spinning machine according to claim 2, wherein it is determined whether or not piecing has been performed by the weight based on an average value with respect to the winding amount of the weight at the time of measurement. 4. 4. The whole weight is divided into a plurality of groups, and the sub-control unit includes a first sub-control unit provided for each weight, and a first sub-control unit provided for each group. 4. The yarn breakage detecting device for a spinning machine according to claim 2, further comprising a second sub-control unit that relays transmission and reception of signals to and from the main control unit. 5. The first determining means calculates an average value and a standard deviation from the current value of each weight, and determines a weight whose current value data deviates from the average value by a predetermined ratio or more of the standard deviation as a yarn breakage. The yarn breakage detecting device in a spinning machine according to any one of claims 2 to 4. 6. The thread breakage judging device according to claim 2, wherein the second judging device judges the thread breakage using the current value corrected based on a difference between a winding amount and a spindle rotation speed. A yarn breakage detecting device for a spinning machine according to the above. 7. The yarn breakage detecting device for a spinning machine according to claim 2, wherein said both judging means makes a yarn breakage determination except at the time of starting / stopping.