JPS6214462B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a single yarn movement detection device for multi-filament yarn winding at high speed.

In recent years, in order to increase the productivity of yarn spinning, high-speed spinning and winding techniques for multi-filament yarns, such as direct spinning, drawing and winding of multi-filament yarns and highly oriented undrawn yarn take-up, have been studied.

The biggest problem in such multi-filament, high-speed yarn winding is yarn shaking on the drawing roller (usually a Nelson roller is used in direct spinning and drawing). That is, for example 2000m/
Since the yarn is wound at a high speed of more than 1 minute (currently possible up to about 8000 m/minute), the yarn is wound by the accompanying airflow that is inherent to high-speed rotation, especially in the pair of drawing rollers (22nd Godet roller) made of Nelson rollers. If the yarn is shaken violently and there are many yarns, the pitch between each yarn is narrow, so the effects of the yarn shake, such as single yarn movement and single yarn breakage, are more pronounced.

When single yarn movement or single yarn breakage occurs due to yarn swinging, the quality of the wound raw yarn (to become a product) deteriorates. In particular, the raw thread for tricots appears as vertical stripes and vertical stripes, and the raw thread for eyelash fabrics appears as horizontal row unevenness, both of which result in defects.

The purpose of the present invention is to quickly detect single yarn movement caused by the yarn shaking that is inherent in multi-filament yarns and high-speed yarn winding, to prevent defects from occurring at that point, and to improve the quality of the product raw yarn. An object of the present invention is to provide a single yarn movement detection device that can improve the performance of the yarn.

To achieve this object, the present invention provides a single yarn movement detection device having a yarn path sensor, a controller, and an alarm, wherein the yarn path sensor is n (n is an integer).
It has a pair of emitter and receiver, and a light-shielding mask is provided on at least the lens surface of the receiver, and the controller has a circuit that compensates for the decrease in sensitivity of the yarn path sensor and clamps the generation of an alarm for a certain period of time when disturbance light is incident. It has a circuit.

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 is a front view of the direct spinning/drawing device (part) equipped with a yarn path sensor, and Figure 2 is the same as in Figure 1.
3 is a perspective view A and a plan view B for explaining the operation of the yarn path sensor, and FIGS. 4 and 5 are plan views of a light receiver with a light shielding mask provided on the lens surface. Figure A and side view B, Figure 6 are block diagrams showing the configuration of the single yarn movement detection device, Figure 7 is a circuit diagram of the same device, Figure 8 is a basic circuit diagram for explaining sensitivity compensation, Figure 9 FIGS. A and B are waveform diagrams for explaining sensitivity compensation, and FIGS. 10A to 10J are waveform diagrams for explaining alarm generation when single yarn movement occurs and alarm clamping when disturbance light is incident.

In Fig. 1, multifilament multi-filament yarns Y (in this example, four yarns Y1 to Y4) are spun from a spinneret 1, passed through a cooling chimney 2, and cooled and solidified.
is oiled by the oiling roller 3, taken over by the Godet rollers 5, 5' (consisting of Nelson rollers) via the direction change guide 4, and then taken by the drawing hot rollers 6, 6' (consisting of Nelson rollers). It is stretched and heat treated, and wound up as a package via an exit guide 9 in a winder (not shown). 7 is a heat insulation cover.

In FIG. 2, 7' is the openable/closeable lid of the heat insulation cover 7, and 8 and 8' are the stretching hot rollers 6,
6' are each drive motors.

What is important here is that a yarn path sensor 10, which is a single yarn movement detection device, is provided between the yarn separation point P of the drawing hot roller 6' and the exit guide 9.

The operation of the yarn path sensor 10 will be explained using FIG. 3.

Thread path sensor 1 consisting of an embodiment shown in FIG.
0 uses a photoelectric element. That is, on one of the opposite sides of the holder H, which is formed in a substantially U-shape, there are light projectors E1 to E such as light emitting diodes.
3, and at the corresponding positions of the other, photoreceivers R1 to R3 each consisting of a phototransistor or the like.
have. Note that in this example, there are 4 threads, so 3
Pairs of emitter/receiver (E1/R1 to E3/R3) are provided, but generally when running n yarns (n≧2, integer) in parallel, (n-1) pairs of emitter/receiver are provided. All you have to do is set it up.

Now, suppose that the four yarns Y1 to Y4 are running between the yarn separation point P and the exit guide 9 as shown in FIG. The yarn path sensor 10 is installed at a position. Therefore, in a normal running state in which no single yarn movement occurs, each light beam does not intersect with each yarn, and each of the light receivers R1 to R3 receives the maximum amount of light.

However, due to the accompanying airflow of the drawing (hot) roller 6' that rotates at high speed, the yarn swings violently, and the adjacent yarns (Y1 and Y2, Y2 and Y
3. If one or more filaments among the multifilaments constituting each yarn move between Y3 and Y4), in other words, a single filament moves, immediately A decrease in the amount of light received is detected by the yarn path sensor 10, and after the signal is processed by a controller (not shown), an alarm is generated by an alarm means (not shown) such as a lamp or a buzzer.

As a result, two yarns Yi, Yi+
Regarding No. 1, winding can be interrupted at that point to prevent the occurrence of defective rolls. Note that winding can be continued for yarns (other than Yi, Yi+1) in which single yarn movement has not occurred, or winding can be continued in the same way as for two yarns (Yi, Yi+1) in which single yarn movement has occurred. You may interrupt the session.

In addition, in the present invention, the lenses (hemispherical convex lenses) of the projectors E1 to E3 and the light receivers R1 to R3
As shown in Figures 3 to 5, the holder H
protruding from the wall. Therefore, it has excellent light focusing ability, and dirt such as oil droplets does not easily adhere to the vicinity of the top of the hemisphere where the sensitivity is highest, and even if it adheres to other parts, it can be easily wiped off and cleaned.

Further, as shown in FIGS. 4 and 5, a light shielding mask M is provided at least on the lens surface of the light receiver R. A light emitting diode or the like having sharp directivity can be used as the light projector E, but a light shielding mask M may be provided if necessary. The position of the opening O of the light-shielding mask M is preferably a position passing through the top of the hemisphere, and its shape is a rectangular shape with 0<θ<180° as shown in Fig. 4, or a rectangular shape with θ = 180° as shown in Fig. 5. A rectangular shape is preferred. Furthermore, the yarn path sensor 1 is placed so that the long side of the opening O is parallel to the running direction of the yarn Y.
Preferably, 0 is provided. Opening width W
is preferably about 1 mm, for example. The distance L between the emitter and receiver is preferably about 10 to 15 mm. The light-shielding mask M can be provided by plating, vapor deposition, coating, adhesion, or the like.

As described above, in the present invention, since the light-shielding mask M is provided at least on the lens surface of the light receiver R, it is less susceptible to disturbance light than the conventional sensor without a light-shielding mask, and the signal-to-noise ratio (S/ N) can be increased and the detection sensitivity can be increased by focusing the light on the top of the hemispherical convex lens.

The single yarn movement detection device of the present invention includes such a yarn path sensor 10, a controller 11, and an alarm 1.
2 are connected (see Figure 6). The details of the circuit are as shown in Figure 7 (however,
(This is a circuit for a pair of emitter and receiver). Thread path sensor 1
0 consists of a light emitting diode LED as a light emitter E, a phototransistor PhTr as a light receiver R, and a current limiting resistor R1 for the light emitting diode LED.

The controller 11 has a sensitivity compensation circuit and an alarm clamp circuit. First, the sensitivity compensation circuit will be explained using the basic circuit shown in FIG.

In steady state, the emitter E (light emitting diode
A light beam of constant intensity is projected from the LED (see Figure 3). Therefore, the output current of the photoreceiver R (phototransistor PhTr) is constant, and _a constant DC voltage _V1 (usually 2~
6V) is occurring. A part of the DC voltage V ₁ is smoothed by a diode D, a capacitor C ₂ and a resistor R ₄ , and is used as the reference voltage Vs of the comparator C.

On the other hand, the circuit portion consisting of the capacitor C ₁ , the resistor R ₃ and the inverting amplifier is for processing a negative pulse (described later, see FIG. 10A) that appears when a single thread movement occurs. In other words, the AC signal (negative pulse) that is superimposed on the DC voltage V ₁ when a single yarn movement occurs is extracted by cutting off the DC component with a capacitor C ₁ and a resistor R ₃ , amplified with an inverting amplifier to make a positive pulse, and then outputted to a comparator. Input voltage to C
Let it be Vi.

The relationship among the input voltage Vi, reference voltage Vs, and output voltage _V0 of the comparator C is shown in FIGS. 9A and 9B. In Figure 9A, the input voltage Vi is the reference voltage
Output voltage V ₀ is generated only when it becomes greater than Vs. This output signal V ₀ activates the alarm 12 . FIG. 9B shows a case where dirt adheres to the lens surface of the emitter E or the light receiver R. At this time, the output voltage V ₁ decreases, so
Although the reference voltage Vs' becomes smaller (Vs'<Vs), the input voltage Vi' also becomes correspondingly smaller (Vi'<Vi).
Therefore, even if the sensitivity decreases due to dirt on the lens surface, the timing at which the comparator C output V ₀ occurs does not change, and the magnitude (level)
remains the same. This is the basic type of sensitivity compensation circuit. The actual circuit is as shown in FIG. In steady state, the output voltage V ₁ of PhTr is constant (FIG. 10A).

Tr ₁ is a FET (field effect transistor), which is a source follower and works as an impedance converter. Since the gate leakage current is extremely small, the output voltage V ₁ of the PhTr directly becomes the DC voltage V ₂ (FIG. 10B).

The source voltage of Tr ₁ is a voltage V ₂ ′, which is slightly lower than the voltage V ₂ . The source voltage V ₂ ' is divided by resistance to obtain the reference voltage V ₅ of the comparator C (for example,
100mV level).

On the other hand, when single yarn movement occurs, the single yarn (filament) is adjacent to (multifilament)
Because it vibrates back and forth between the threads,
The output of PhTr decreases almost periodically. That is, as shown by the broken line in FIG. 10A, the output voltage
Generates an AC signal (negative pulse) with non-uniform magnitude based on the level of V ₁ . Its magnitude is about 60 to 120 mV when the single fiber denyl is 4 denyl. Note that the magnitude of V ₁ is on the order of 2 to 6 V, and for convenience of explanation, the magnitude of the negative pulse is enlarged.

After cutting off the DC component with capacitor _C2 , the AC signal is amplified 10 times using an amplifier. At this time,
Since it is input to the negative terminal of the amplifier (inverting amplifier), the output voltage V ₃ (FIG. 10C) is inverted and becomes a positive pulse.

The output _V6 of comparator C is shown in Fig. 10D and E.
As shown in , if the input voltage V ₄ <reference voltage V ₅ , the voltage is +12V, and conversely, if V ₄ >V ₅ , the voltage is −12V.

In steady state, with no negative pulses, V ₆ is +12V, and the resistance is increased by the reverse blocking diode D _1.
No current flows through R ₁₁ , R ₁₂ and capacitor C ₄ .

However, single thread movement occurs and a negative pulse is generated.
When V ₄ > V ₅ , V ₆ drops to −12V, so D ₁
conducts, and the voltage V ₇ increases in the negative direction (10th
(dashed line in Figure F). Until V ₇ reaches the pinch-off voltage Vp of Tr ₂ , the drain current flows through Tr ₂ (Tr ₂ is on), so no current flows through the base of Tr ₃ (Tr ₃ is off).

When V ₇ reaches the pinch-off voltage Vp of Tr ₂ , Tr ₂
Drain current no longer flows to (Tr ₂ is off),
Current flows to the base of Tr ₃ , turning Tr ₃ on. Therefore, as shown by the broken line in FIG. 10G, an alarm output _V8 is generated and the alarm 12 is activated.

Next, the alarm clamp circuit will be explained.

Disturbing light (for example, light from a flashlight for inspection, etc.) is transmitted through the opening O of the mask M of the receiver R (Fig. 4,
(Fig. 5), the amount of PhTr received increases, so the output is as shown by the two-dot chain line in Fig. 10A.
V ₁ increases. As a result, the voltage V ₂ across the capacitor C ₁ also increases slightly (double-dashed line in FIG. 10B).

The output V ₃ of the inverting amplifier is
As the capacitor C ₂ is charged, it becomes negative at some point as shown by the dotted chain line C2 in Figure 10, but when the disturbance light disappears, it returns to positive due to the discharge of C ₂ .

Now, since the alternating current signal component (negative pulse) of the output V ₁ due to single thread movement and the positive noise of the output V ₁ due to the incidence of disturbance light have opposite polarities, if these are input directly to the comparator C, the disturbance light will be reduced. Not affected. However, in the present invention, since the alternating current signal is inverted and amplified using an inverting amplifier and then input to the comparator C, the polarity becomes the same during the inverting amplification. Since the magnitude of the positive noise caused by the incidence of the disturbance light is larger than the AC signal caused by the movement of a single yarn, an alarm is issued due to the noise of the disturbance light.

An alarm clamp circuit is necessary to prevent malfunctions caused by such disturbance light.

Since Tr ₄ is a PNP type transistor, it does not operate when the output V ₃ of the inverting amplifier is positive.
However, when disturbance light enters and the voltage V ₃ becomes negative as shown by the two-dot chain line in Figure 10C, Tr ₄ turns on and the voltage V ₉ rises (Figure 10H. From -12V to approximately - to 2V).

When voltage V ₉ rises, voltage V ₁₀ also rises through diode D ₃ (Fig. 10), and capacitor C ₅
will be charged immediately. Until voltage V ₁₀ rises, voltage V ₁₁ remains close to -12V (FIG. 10J). Therefore, the gate of Tr ₆ is kept negative,
Tr ₆ is also off.

When voltage V ₉ rises and therefore voltage V ₁₁ also rises, the gate of Tr ₆ becomes positive and Tr ₆ is turned on. As a result, capacitor C ₄ discharges,
Since the voltage V ₇ returns to 0V (indicated by * in Fig. 10F), Tr ₃ turns off and the alarm output V ₈ becomes
It becomes 0V. That is, the alarm 12 does not operate.

Thereafter, the voltage V ₁₀ decreases due to the discharge of the capacitor C ₅ (FIG. 10), and V ₁₁ falls near -12V (FIG. 10 J).

Therefore, Tr ₆ is turned off, capacitor C ₄ begins to be charged, and voltage V ₇ increases again in the negative direction. When V ₇ reaches the pinch-off voltage Vp of Tr ₂ , Tr ₃ is turned on and an alarm output V ₈ is generated (FIG. 10G). Therefore, the alarm 12 is activated. In this case, time t in FIG. 10G is the alarm clamp time. The length of this time t can be arbitrarily changed by selecting the values of circuit elements (transistors, capacitors, etc.), for example, the values of R ₂₀ , C ₅ , R ₂₂ , R ₂₁ and the characteristics of TR ₅ . .

For convenience, here we have explained a special case in which disturbance light is incident while single yarn movement is occurring, but in reality, both single yarn movement and disturbance light incident rarely occur, so they may occur simultaneously as shown in Figure 10. It is extremely rare to do so.

Also, in the case of not only ambient light but also electrical noise, if the output _V3 of the inverting amplifier reaches a certain negative level (for example, -1.5V), the alarm generation is similarly clamped for a certain period of time t. be able to.

As explained above, since the present invention has the above configuration, it can achieve the following effects.

Since a light-shielding mask is provided on at least the lens surface of the light receiver, it is less susceptible to disturbance light and has a higher signal-to-noise ratio (S/N) than a conventional yarn path sensor without a light-shielding mask. Sensor sensitivity can be improved.

Since the controller has a sensitivity compensation circuit, even if there is dirt such as oil droplets on the lens surface of the emitter or receiver, it will generate an alarm output at exactly the same timing as when there is no dirt.
Moreover, the magnitude of the output is not reduced. Therefore, the alarm can be operated reliably even in an oil mist atmosphere.

Since the controller has an alarm lamp circuit, even if disturbance light such as light from an inspection flashlight enters the mask opening of the receiver, the alarm occurrence will be clamped for a certain period of time to prevent false alarms. can do. Therefore, reliability can also be improved.

Since single yarn movement can be detected quickly and defective yarns can be prevented from occurring at that point, the quality of the product raw yarn can be improved.

[Brief explanation of the drawing]

Figure 1 is a front view of the direct spinning/drawing device (part) equipped with a yarn path sensor, and Figure 2 is the same as in Figure 1.
3 is a perspective view A and a plan view B for explaining the operation of the yarn path sensor, and FIGS. 4 and 5 are plan views of a light receiver with a light shielding mask provided on the lens surface. Figure A and side view B, Figure 6 are block diagrams showing the configuration of the single yarn movement detection device, Figure 7 is a circuit diagram of the same device, Figure 8 is a basic circuit diagram for explaining sensitivity compensation, Figure 9 FIGS. A and B are waveform diagrams for explaining sensitivity compensation, and FIGS. 10A to 10J are waveform diagrams for explaining alarm generation when single yarn movement occurs and alarm clamping when disturbance light is incident. 10... Thread path sensor, 11... Controller, 12
...Alarm.

Claims (1)

[Claims] 1 A single yarn movement detection device having a yarn path sensor, a controller, and an alarm, wherein the yarn path sensor is
It has a pair of emitter and light receiver (n is an integer), and a light-shielding mask is provided on at least the lens surface of the light receiver, and the controller has a circuit that compensates for the decrease in sensitivity of the yarn path sensor and generates an alarm when disturbance light is incident. A single yarn movement detection device that has a circuit that clamps the yarn for a certain period of time.