JPH06248525A - Yarn breakage detector in spinning machine - Google Patents

Abstract

PURPOSE:To provide a detector enabling the presence/absence of yarn breakage in each spindle to be continuously detected and ensuring yarn breakage to be detected in a simple configuration even if a traveler is inertially rotated in yarn breakage. CONSTITUTION:Pickup coils 6a, 6b are wound independently on the respective blades of a traveler clearer shared by two spindles. The respective output terminals of the pickup coils 6a, 6b are connected to the respective reverse input terminals of comparators 11a, 11b. Variable resistors 12a, 12b as standard voltage setting means are respectively connected to the non-reverse input terminals of said comparators 11a, 11b. The standard voltage is set at such a voltage as to be generated in the pickup coils 6a, 6b when a traveler is rotated at a number of revolutions between that in its inertial rotation and that in its normal rotation. Depending on the interrelation between the respective magnitudes of the standard voltage and the output voltages from the pickup coils 6a, 6b, different signals corresponding to the presence/absence of yarn breakages are given from the comparators 11a, 11b.

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 device for a spinning machine such as a ring spinning machine and a ring twisting machine, and more particularly, to detecting a yarn breakage of a spinning machine equipped with an electromagnetic pickup type detector for detecting the rotation of a traveler. It relates to the device.

[0002]

2. Description of the Related Art A yarn breakage detecting device of this type is disclosed in Japanese Patent Laid-Open No.
3-58035 and JP-A-55-40847 disclose a detector including a magnetic core wound by a winding.
A device is disclosed which is movably mounted along a guide rail fixed on a ring rail. In this device, one detector is moved along the guide rail in order to suppress an increase in cost when a detector is provided for each weight.
Then, the detectors are sequentially arranged at positions corresponding to the respective weights,
The presence or absence of yarn breakage is determined based on the induced voltage generated in the winding when the traveler passes near the magnetic core.

Further, Japanese Patent Laid-Open No. 58-74464 discloses that
An electromagnetic detector that detects the presence or absence of yarn breakage by utilizing the electromagnetic induction effect of the traveling of the traveler, and a yarn breakage detection head consisting of an amplifier that amplifies the signal from this detector were built in the separator of each weight. A device is disclosed. Further, the separator of each weight has a built-in storage circuit for storing a signal from the yarn breakage detection head by a data latch signal from the outside. Each memory circuit is connected so that the memory signals are sequentially shifted one by one from the one at the one end to the one at the other end by a shift signal from the outside to form a shift register. In this device, a data latch signal is simultaneously output to each weight for a predetermined time, and the presence or absence of a pulse signal based on the rotation of the traveler from the detector is stored in the memory circuit within that time. Then, after that, the presence / absence of the pulse signal stored in each memory circuit is sequentially sent to the discriminating device provided at the machine body end portion by the shift signal to discriminate the presence / absence of yarn breakage of each weight.

[0004]

Problems to be Solved by the Invention JP-A-53-5805
In the devices disclosed in Japanese Patent Laid-Open No. 3 and JP-A-55-40847, one detector moves on the ring rail to detect the yarn breakage of each weight. It cannot be detected continuously. Also, the interval for detecting thread breakage of the same weight becomes relatively long. This is because it is premised that there is no problem even if the presence or absence of yarn breakage of each weight is intermittently detected at predetermined time intervals without continuously monitoring all weights from the statistical analysis in the spinning factory. is there. When the operating speed of the machine base was relatively low, the presence or absence of thread breakage of each weight was intermittently detected in this way, and there was no problem even if the interval was relatively long. However, due to the increase in operating speed of the machine base, such a premise is not always correct, and a large amount of cotton is wastefully discharged at the yarn breakage weight. There is also a problem that a mechanism for moving the detector along the ring rail is required, which makes it difficult to assemble and maintain the ring spinning machine.

Further, each of the yarn breakage detecting devices is adapted to judge the presence / absence of a yarn breakage based on the presence / absence of a pulse signal generated based on the rotation of a traveler. However, since the spindle continues to rotate even in the yarn breakage state, the traveler may be accompanied by various causes. There are the following three reasons for being accompanied.

(1) When the yarn is broken, a few cm of the yarn end that is continuous with the bobbin (tubular yarn) and does not pass through the traveler is swung by the centrifugal force, and the yarn end hits the traveler, causing the traveler to rotate irregularly.

(2) The fluff on the surface of the tube thread hits the traveler to rotate the traveler (when the tube thread and the traveler are close to 1 mm, the fluff hits the traveler when the tube is close to full). (3) The traveler rotates due to the accompanying air flow caused by the rotation of the yarn. Then, mainly due to (2) and (3), the traveler rotates around, and the traveler rotates at several hundred rotations / minute. as a result,
There is a problem that a pulse signal may be generated despite the yarn breakage state, and it may not be possible to determine “thread breakage”.

The present invention has been made in view of the above problems, and an object thereof is to continuously detect the presence or absence of yarn breakage in each weight, and to make it simple even if a traveler turns around at the time of yarn breakage. It is an object of the present invention to provide a yarn breakage detecting device for a spinning machine, which is capable of reliably detecting a yarn breakage.

[0009]

In order to achieve the above object, in the present invention, the presence or absence of a yarn is detected by utilizing an electromagnetic induction action by a traveler made of a magnetic material rotating on a ring crossing a magnetic circuit. In the yarn breakage detection device of the spinning machine,
Reference voltage setting means for setting a predetermined reference voltage for yarn breakage determination, and comparison means for comparing the output voltage generated in the sensor by the rotation of the traveler with the reference voltage set by the reference voltage setting means are provided. .

[0010]

When the traveler moves on the ring and crosses the magnetic circuit, a voltage is induced in the sensor by the electromagnetic induction action. The voltage induced in the sensor increases substantially in proportion to the traveling speed of the traveler, that is, the rotation speed. The output voltage of the sensor is compared with a predetermined reference voltage set by the reference voltage setting means for the thread breakage determination in the comparison means. If the output voltage of the sensor is higher than the reference voltage,
The comparison means outputs a signal indicating a normal state. If the output voltage of the sensor is lower than the reference voltage,
The comparison means outputs a signal indicating that the yarn is in a broken state.

[0011]

【Example】

(First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 3 to 5, the thread breakage detection sensor 1 is integrated with the traveler clearer 2. The traveler clearer 2 is formed of a plate material made of a magnetic material, and includes a clearer main body 2a and a pair of blade portions 2b branching left and right from the tip of the clearer main body 2a. Both blade portions 2b are bent upward at a right angle to the clearer main body 2a, and are formed so as to extend outwardly from each other, and cutting edges are formed at their tips. A slot 3 is formed near the base end of the clearer body 2a so as to extend in the longitudinal direction of the clearer body 2a.

The traveler clearer 2 also serves as a magnetic core, and the lower surface of the clearer main body 2 has a permanent magnet 4 for magnetizing the magnetic core.
Is stuck. The S pole of the permanent magnet 4 is the ring rail 5
It is fixed so that it is on the side. A first pickup coil 6a and a second pickup coil 6b as a sensor body are independently wound around each blade portion 2b. Each pickup coil 6a, 6b is connected to the determination device 7.

A screw hole 5a (shown only in FIG. 5) is formed at a predetermined position on the front side (lower side in FIG. 3) of the ring rail 5. The traveler clearer 2 is fixed on the ring rail 5 with a screw 9 in a state of extending between the adjacent rings 8 provided on the ring rail 5 in a direction orthogonal to the longitudinal direction of the ring rail 5. As shown in FIG. 5, a packing 10 made of a non-magnetic material is interposed between the lower surface of the clearer main body 2 a and the upper surface of the ring rail 5, and the traveler clearer 2 has the permanent magnet 4 on the upper surface of the ring rail 5. It is fixed in contact. The screw 9 is also made of a non-magnetic material.

As shown in FIG. 1, the judging device 7 includes a first comparator 11a and a second comparator 11b as comparing means, and a first variable resistor 12a and a second variable resistor as reference voltage setting means. 12b is provided. Both comparators 11a and 11b and both variable resistors 12
a and 12b are provided corresponding to the pickup coils 6a and 6b, respectively. As shown in FIG. 2, the power source Vcc is connected to the first power source terminal of each of the comparators 11a and 11b, and the second power source terminal is grounded. Each of the pickup coils 6a and 6b has a first terminal grounded and a second terminal corresponding to the corresponding comparator 11a, 11b.
It is connected to the inverting input terminal of b. Also, each variable resistor 1
2a and 12b are connected to the non-inverting input terminals of the comparators 11a and 11b. Note that FIG. 2 illustrates only the first comparator 11a. The reference voltage input to the non-inverting input terminal of each comparator 11a, 11b is set by adjusting the variable resistors 12a, 12b. The reference voltages Va0 and Vb0 are the pickup coils 6a and 6b when the traveler 14 rotates at a rotation speed between the rotation speed of the traveler 14 when the traveler 14 rotates and the rotation speed of the normal rotation.
It is set to the voltage that occurs at.

Next, the operation of the apparatus configured as described above will be described. Due to the action of the permanent magnet 4 fixed to the rear surface of the clearer main body 2a, a magnetic circuit composed of magnetic fluxes from the north pole to the south pole of the permanent magnet 4 is formed in the traveler clearer 2, the ring rail 5, and the ring 8. It Since the traveler clearer 2 is fixed to the ring rail 5 via the screw 9 and packing 10 made of a non-magnetic material, most of the magnetic flux passes through both the blade portions 2b toward the ring flange 8a. Then, it returns to the S pole of the permanent magnet 4 through a part of the ring 8 and the ring rail 5. Therefore, the traveler clearer 2 is formed with two magnetic circuits passing through a part of the ring flanges 8a of the adjacent rings 8.

When the yarn 13 rotates with the rotation of a spindle (not shown) during the spinning operation, the traveler 14 moves on the ring flange 8a at a speed corresponding to the rotational speed of the yarn 13 unless the yarn is in a broken state. Rotate. And the traveler 1
Each time 4 rotates once on the ring flange 8a, it crosses the magnetic circuit once. When the traveler 14 crosses the magnetic circuit, the magnetic flux φ of the magnetic circuit changes, and a voltage V shown by the following equation, which is proportional to the number of turns N of the coil, is induced in each of the pickup coils 6a and 6b.

V = N (dφ / dt) Then, while the traveler 14 is rotating, the voltages Va and Vb induced by the rotation of the traveler 14 from the respective pickup coils 6a and 6b are applied to the comparators 11a and 11b.
It is input to the inverting input terminal of b. When the traveler 14 stops rotating, the voltage input to the inverting input terminals of the comparators 11a and 11b becomes 0 volt. The reference voltages Va0 and Vb0 are input to the non-inverting input terminals of the comparators 11a and 11b.

Since both pickup coils 6a and 6b and the comparators 11a and 11b have the same operation, the first and second coils will be described below.
Pickup coil 6a and first comparator 11
A will be described. The output voltage Va of the pickup coil 6a input to the comparator 11a is the reference voltage Va0.
If smaller, the output of the comparator 11a becomes Vcc. On the other hand, when the output voltage Va of the pickup coil 6a input to the comparator 11a is higher than the reference voltage Va0, the output of the comparator 11a becomes 0 volt.

Magnetic flux φ per unit time in the magnetic circuit
(Dφ / dt) is substantially proportional to the moving speed of the traveler 14. Therefore, the output voltage Va of the pickup coil 6a is substantially proportional to the number of revolutions of the traveler 14 per unit time. On the other hand, when the traveler 14 rotates at a rotation speed between the reference voltage Va0 and the normal rotation speed of the traveler 14, the pickup coils 6a and 6a are rotated.
It is set to the voltage generated in b. Therefore, even if the output voltage Va is generated from the pickup coil 6a in synchronism with the rotation of the traveler 14 at the time of yarn breakage, the value is always smaller than the reference voltage Va0 as shown in FIG. As a result, the output of the comparator 11a becomes constant at Vcc regardless of the presence or absence of accompanying rotation.

On the other hand, in a normal state where no yarn breakage occurs, the pickup coil 6a outputs a pulse voltage whose maximum value is larger than the reference voltage Va0 every time the traveler 14 makes one revolution. As a result, as shown in FIG. 7, the output from the comparator 11a is 0 while the output voltage Va of the pickup coil 6a exceeds the reference voltage Va0.
The voltage is V and becomes Vcc while it is lower than the reference voltage Va0. That is, when no thread breakage occurs, the output of the comparator 11a becomes a rectangular pulse synchronized with the rotation speed of the traveler 14.

Therefore, the output signal from the comparator 11a is completely different when the yarn breakage occurs and when the normal spinning is performed, and the presence or absence of the yarn breakage can be immediately determined based on the output signals of the comparators 11a and 11b. It is not normally possible to run a ring spinning machine at a spindle speed of 3000 revolutions per minute or less. On the other hand, the speed at which the traveler 14 rotates due to the accompanying rotation is several hundred rotations / minute even at a high speed. Therefore,
The difference between the two is very large. For example, if the reference voltage Va0 is set to a voltage corresponding to the induced voltage when the rotation speed of the traveler 14 is 1500 revolutions / minute, it can be clearly discriminated from the output voltage during the accompanying rotation. . Also, each pickup coil 6
The output voltage Va from a and 6b varies in magnitude due to the difference in the traveler 14 and the difference in the distance between the traveler 14 and the traveler clearer 2. However, if the difference between the reference rotational speed for setting the reference voltage and the rotational speed during rotation is large as described above, erroneous determination does not occur even if the reference voltage is not adjusted accurately. . Therefore, accurate adjustment of the reference voltage is unnecessary.

By providing the yarn breakage detecting device on all the weights, the yarn breakages of the respective weights are continuously detected.
Therefore, by checking in which state the output of each judging device 7 is, it is possible to judge whether or not each weight is broken, with high accuracy and in a short response time.

If the spindle rotation speed reaches a predetermined value at the time of starting the machine base, or if the spindle rotation speed becomes less than or equal to the predetermined value when the machine base is stopped, the judging device 7 Even if the thread breakage detection signal is output from
It is not always a thread break.

(Second Embodiment) Next, a second embodiment will be described with reference to FIGS.
Follow the instructions below. This embodiment is largely different from the above embodiment in that the judging device 7 includes a noise removing means 15 for the output signal of the pickup coil 6 and a holding circuit 16 for holding the yarn breakage judgment of the comparator 11. The noise removing means 15 is composed of a low-pass filter LPF including a resistor R and a capacitor C, and is connected between the pickup coil 6 and the comparator 11. The holding circuit 16 is composed of a monostable multivibrator, and the output terminal of the comparator 11 is connected to the input terminal thereof. A driver circuit 17 as an input / output interface is connected to the holding circuit 16. Driver circuit 17
Is composed of TTL (transistor-transistor logic).

If the output signal of the pickup coil 6 contains noise larger than the reference voltage V, the output of the comparator 11 is not constant even when the yarn is broken, and a pulse corresponding to the noise is generated. However, in this device, even if the output signal from the pickup coil 6 contains noise, the noise is removed when the output signal passes through the low-pass filter LPF. Therefore, the output of the comparator 11 becomes constant at the time of yarn breakage, and there is no risk of erroneous detection.

In the yarn breakage state, the output of the comparator 11 becomes constant, so that the holding circuit 16 holds the output high (H). Further, since the comparator 11 outputs a pulse signal that repeats low (L) and high (H) at a predetermined interval in a state where the yarn is not broken, the output of the holding circuit 16 becomes a rectangular pulse signal having a predetermined cycle. Then, the output signal is output to a control device (not shown) via the driver circuit 17.

The present invention is not limited to the above-described embodiments, and for example, one variable resistor may be shared by both comparators 11a and 11b in the first embodiment. Since there is a large difference between the number of revolutions that is the criterion for yarn breakage determination and the number of revolutions when the yarn is rotated together, it is not necessary to strictly adjust the reference voltage for each weight, and there is no problem in sharing it.
If the spinning conditions are not changed significantly, it is not necessary to change the reference voltage, and even if the reference voltage is set by using two fixed resistors instead of the variable resistors as the reference voltage setting means. Good.

Further, the thread breakage detection sensor 1 may be replaced by a structure in which two weights are commonly used, and an independent structure may be provided for each weight, or a detection sensor other than a structure in which a pickup coil is incorporated in the traveler clearer 2 may be used. Further, the permanent magnet may have the N pole side fixed to the ring rail 5 side.

Further, the reference voltage may be input to the inverting input terminal of the comparator and the output of the pickup coil may be input to the non-inverting input terminal. In this case, if the output voltage of the pickup coil is lower than the reference voltage, the output of the comparator is 0 volt, and if the output voltage of the pickup coil is higher than the reference voltage, the output of the comparator is Vcc. Therefore, when the yarn is broken, the output of the comparator becomes constant at 0 volt. On the other hand, in a normal state, a pulse signal that becomes Vcc is output from the comparator every predetermined period in synchronization with the rotation of the traveler.

Further, it is not necessary to provide all of the noise removing means 15, the holding circuit 16 and the driver circuit 17, and they may be properly provided as needed. Also, the driver circuit 1
A transistor may be used instead of 7.

[0031]

As described in detail above, according to the present invention, the presence or absence of yarn breakage in each weight can be continuously detected, and even if the traveler rotates along with the yarn breakage, the yarn breakage can be reliably performed with a simple structure. Can be detected.

[Brief description of drawings]

FIG. 1 is a block diagram of a yarn breakage detecting device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of the same.

FIG. 3 is a schematic plan view showing a state in which a thread breakage detection sensor is attached to a ring rail.

4 is a sectional view taken along line IV-IV in FIG.

5 is an enlarged sectional view taken along line VV of FIG.

FIG. 6 is a diagram showing changes in voltage output from a pickup coil and a comparator when a yarn breaks.

FIG. 7 is a diagram showing changes in voltage output from a pickup coil and a comparator during normal spinning.

FIG. 8 is a block diagram of a yarn breakage detecting device according to a second embodiment.

FIG. 9 is a circuit diagram of the same.

[Explanation of symbols]

1 ... Thread breakage detection sensor, 6a, 6b ... Pickup coil as sensor body, 11a, 11b ... Comparator as comparison means, 12a, 12b ... Variable resistance as reference voltage setting means, 14 ... Traveler, Vcc ... Power supply, Va0
... reference voltage.

Claims (1)

[Claims] 1. A yarn breakage detecting device for a spinning machine, which detects the presence or absence of a yarn by utilizing an electromagnetic induction effect of a traveler made of a magnetic material rotating on a ring crossing a magnetic circuit, and a predetermined yarn breakage determination device. A yarn breakage detecting device for a spinning machine, comprising: a reference voltage setting means for setting the reference voltage of 1. and a comparing means for comparing the output voltage generated in the sensor by the rotation of the traveler with the reference voltage set by the reference voltage setting means.