JP2003106916A - Tensile force detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tensile force detector capable of providing high measurement precision when adopting a tensile force detection system for a thread winder. SOLUTION: In this tensile force detector 2 for detecting a thread tensile force based on the fluctuation of a probe 3 generated when traversing a thread S engaged with the probe 3 supported on a support body 6 so as to swing, a vibration damping means D formed into a baglike form made of silicone rubber across the probe 3 and the support body 6 is provided. Inherent vibration frequency of the probe 3 is reduced due to the reduction of rigidity of the probe 3 to increase detection sensitivity. As a result, even when the probe 3 is easily affected by its own resonance frequency, the vibration damping means D damps amplitude by the inherent vibration frequency of the probe 3 to suppress vibration component by inherent vibration frequency in a detection signal to a small value and keeps an output within a detection possible scope so that accurate tensile force can be detected by the tensile force detector having high sensitivity and a tensile force can be precisely controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension detector used for controlling a yarn tension during winding in a yarn winding machine for continuously winding filament yarn of synthetic fiber.

[0002]

2. Description of the Related Art A winding control system in a yarn winding machine, in which a filament yarn of synthetic fibers continuously melt-spun from a spinning machine is wound around a bobbin while traversing by a traverse device, is mainly based on a yarn speed. There are two known types of yarn speed control, which is focused on, and yarn tension control, which is focused on yarn tension.

The former yarn speed control method controls the traverse speed so as to keep the yarn speed constant during the winding process, but hardly considers the change in the yarn tension when the traverse speed is changed, and accordingly, However, it did not control the yarn tension, which is an important factor that determines the winding state of the yarn package.

On the other hand, the latter yarn tension control system is extremely effective in changing the traverse speed during the winding process and performing the winding process for forming a good yarn package without bulges and saddles. It is considered to be a technology.

When the yarn tension control system is adopted, it is necessary to provide a tension detector for contacting the yarn and detecting the tension, but it is not possible to bring the tension detector into contact with the yarn running at high speed. As a general rule, it causes deterioration of yarn quality. Therefore, in order to eliminate adverse effects on the yarn as much as possible, provide a tension detector just downstream of the traverse fulcrum and configured so that the probe slightly swings at both ends of the amplitude of the yarn traversed like a pendulum. Have been proposed (for example, Japanese Patent Publication No. 51-44668 and Japanese Patent Publication No. 60-47).
985).

In the tension detector adopted in the yarn winding machine for introducing the yarn tension control system, the minute stress exerted on the measuring element by the yarn traversed at high speed is accurately detected. Therefore, it is desirable that the detector be as sensitive as possible.

[0007]

In general, a detector that detects a change in an object that behaves dynamically such as a traversed yarn has a natural frequency value in order to avoid resonance with the behavior of the object. , Is designed to be sufficiently higher than the measurement frequency band (used frequency range). However, setting the natural frequency high usually increases the rigidity of the detector, which impairs the sensitivity of the detector. Therefore, it is not desirable for the tension detector which detects the tension by the minute component component of the tension acting on the probe like the above measuring method. Therefore, if the rigidity is designed to be small in order to increase the sensitivity of the detector, the natural frequency of the detector will be low, so it will easily resonate with the operation of the yarn to be detected, and this time,
It may be difficult to detect the tension accurately.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tension detector having high measurement accuracy when the above-mentioned tension detecting system is adopted for a yarn winding machine. The feature of the present invention adopted for the purpose of achieving this object is that it includes a support and a probe that is swingably supported by the support, and that the probe is installed between a traverse fulcrum and a traverse device. The tension detector is adapted to detect the tension of the yarn by engaging with the yarn to be traversed and detecting the fluctuation of the tracing stylus accompanying the traversing motion of the yarn. Among the fluctuations of the tracing stylus caused by the traversing motion of the strip, the vibration damping means for damping the vibration component added to the tracing stylus by the natural frequency of the tracing stylus is provided.

In the tension detector according to the present invention, the rigidity is lowered in order to increase the sensitivity based on the above structure, and the natural frequency of the probe becomes small. As a result, the probe is affected by its own resonance frequency. Even when it becomes easy to receive the vibration, the vibration damping means damps the vibration due to the natural frequency of the probe, and suppresses the vibration component due to the natural frequency included in the detection signal to a small value. Thus, the present invention is capable of performing accurate tension detection with a highly sensitive tension detector.

In the tension detector of the present invention, the natural frequency of the tracing stylus is set higher than the traverse frequency band of the yarn, and the vibration damping means is set to the one of the fluctuations of the tracing stylus. It is desirable that a damping effect be exerted to a greater extent on a vibration component added to the probe due to the natural frequency of the probe, rather than a vibration component only due to the traverse motion of the yarn. Further, the vibration damping means can be a rubber member provided across the probe and the support.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a yarn winding machine for forming a yarn package by winding filament yarns of synthetic fibers continuously melt-spun from a spinning machine while traversing with a traverse device. An embodiment applied to the tension detector will be described. FIG. 1 is a front view showing a schematic configuration of a yarn winding machine M to which the present invention is applied, and one bobbin holder H
A plurality of bobbins B are attached to a plurality of yarn packages P
Are configured so that they can be rolled up at the same time.
The yarn winding machine M includes a bobbin holder H that holds a plurality of bobbins B, and a lifting unit U that includes a traverse device T and a contact roller C on a machine base K. The bobbin holder H is cantilevered on the machine base K and is rotationally driven by a motor (not shown). Generally, in the yarn winding machine M, two bobbin holders H are provided at 180 ° intervals on a turret board rotatably attached to a machine base K, and one bobbin holder H is at a winding position and the other bobbin holder H is on standby. Place it in position and drive. In FIG. 1, the turret board and the bobbin holder H at the standby position are not shown.

The lifting unit U moves up and down with respect to the machine base K,
The contact pressure of the contact roller C to the yarn package P is set to be appropriately maintained. Contact roller C
Are rotatably supported by the lifting unit U and are arranged in parallel with the bobbin holder H. As the traverse device T, for example, a blade traverse device, a cam traverse device or the like is used, and a traverse guide (not shown) for guiding the yarn S in the traverse direction is provided. Further, although not shown, the yarn winding machine M includes upper and lower shifter guides for guiding the yarn S to the catching groove J formed at one end of the bobbin B, and the traverse device T for the yarn S. A thread removing guide or the like for temporarily disengaging from the engagement with is provided.

A traverse fulcrum guide 1 and a tension detector 2 are arranged above the lifting unit U from the upstream side in the yarn traveling direction. The traverse fulcrum guide 1 is for determining a reference position when the traverse device T traverses the yarn S left and right. The structure is, for example, as shown in an enlarged view in FIG. 2, a ring-shaped guide portion 1a through which the yarn S is inserted.
And a base portion 1c supporting the guide portion 1a,
A notch 1b for facilitating the insertion of the thread S into the ring portion 1a is formed at an appropriate position of the guide portion 1a.

A tension detector 2 for detecting the tension of the yarn S traversed by the traverse device T through the traverse fulcrum guide 1.
Are arranged near the lower side of the traverse fulcrum guide 1 on the bisector of the traverse width in the traverse device T corresponding to each, and the yarn S is engaged as shown in FIG. 2 and FIG. And a supporter 6 that supports the probe 3 so as to be swingable in the same direction as the traverse direction of the yarn S. The tracing stylus 3 comprises a holder part 4 for holding the yarn S at the tension detecting position and a shaft part 5 connected to the holder part 4, and the base end part of the shaft part 5 is as shown in FIG. Inside the support body 6, it is connected to a flexible piece 9 such as a thin leaf spring attached to the holding block 7. A pressure sensitive sensor 8 such as a strain gauge is mounted on the flexible piece 9 so as to detect a slight displacement amount of the tracing stylus 3 that occurs when the yarn S is traversed. Note that probe 3
The swing width of is regulated by the cylindrical body 6a provided on the support body 6 into which the shaft portion 5 is inserted.

The holder part 4 of the tracing stylus 3 is formed with a storage portion 4a for the yarn S formed by cutting out an appropriate length from the tip of the central portion in the axial direction. From the inclined side to the left and right tip edges sandwiching the storage portion 4a. Introducing guide portions 4b, 4b are provided. The introduction guide portion 4b formed of an inclined side is for guiding the yarn S into the storage portion 4a, which is the tension detection position, by traversing the yarn S during initial yarn hooking. It is desirable that the probe 3 of the tension detector 2 be made as light as possible in order to detect tension sharply. In this sense, the introduction guide portion 4b formed on the holder portion 4 and having an inclined side contributes to the weight reduction by making the holder portion 4 tapered.

The tension detector 2 has a vibration damping means D interposed between the probe 3 and the support 6. Vibration damping means D
In particular, among the fluctuations of the tracing stylus 3 caused by the traverse movement of the yarn S, the fluctuation (vibration) component added to the tracing stylus 3 by the natural frequency of the tracing stylus 3 is attenuated. As a concrete shape of the vibration damping means D, for example, as shown in FIGS. 3A and 3B, a portion d1 fitted to the shaft portion 5 of the tracing stylus 3 and a portion fitted to the support body 6 are provided. A bag-like form with d2 is conceivable. It is desirable to use a material having flexibility and durability such as silicone resin as the material. The vibration damping means D is attached to the tension detector 2 so as to straddle the tubular body 6a of the support 6 and the shaft portion 5 of the probe 3. As a result, a small gap between the shaft portion 5 and the tubular body 6a is closed, and foreign matter such as oil is evacuated from the support body 6 through the gap.
I try not to infiltrate inside.

The measuring element 3 of the tension detector 2 has a natural frequency set higher than the frequency band used (that is, higher than the maximum traverse frequency). On the other hand, the vibration damping means D has a larger damping effect at the natural frequency (resonance point) of the tracing stylus 3 than at the used frequency band. The tracing stylus 3 fluctuates with the traversing movement of the yarn S, but when the traverse frequency becomes a fraction of the natural frequency of the tracing stylus 3, the tracing stylus 3 may resonate. However, since the tension detector 2 of the present invention includes the above-described vibration damping means D, the resonance phenomenon can be effectively suppressed, and the fluctuation component of the probe 3 due to the traverse frequency is hardly affected. You can choose not to give.

The vibration damping means D shown in FIG. 3 is a rubber member having a bellows portion d3 formed on the peripheral surface thereof, but as shown in FIG. 4, a rubber member having no bellows portion may be used.

The tension detector 2 is arranged immediately below the traverse fulcrum guide 1 (see FIGS. 1 and 2), and the yarn S is traversed by the traverse device T at both ends of the amplitude of the yarn S. S
Is set so as to contact the holder portion 4 of the tracing stylus 3. The yarn S passed through the traverse fulcrum guide 1 is attached to the holder 4
When it is inserted into the storage section 4a of the storage section 4 and wound, the yarn S traversed by the traverse device T is pressed against the left or right inner edge of the storage section 4a at both ends of its amplitude, and the holder section is moved. Swing the shaft part 5 to the left or right through 4,
The flexible piece 9 connected to the base end portion of the shaft portion 5 is deformed. Since the magnitude of the tension of the yarn S correlates with the amount of the force that the yarn S comes into contact with the holder 4 and exerts on the flexible piece 9 through the shaft portion 5, the flexible piece 8 detected by the pressure sensitive sensor 6 is detected. The tension of the yarn S can be calculated based on the deformation amount of the yarn. That is, the tension of the yarn S is calculated by converting the deformation amount of the flexible piece 9 into an electric signal by the pressure sensitive sensor 8 and executing a predetermined calculation on the basis of the electric signal by a separately provided CPU or the like. . The tension detector 2 used in this example has a short contact time with the yarn S, and the bending of the yarn S when contacting with the tension detector 2 is small. It has an advantage that it can be reduced.

In the method in which the tension is detected by detecting the component force of the yarn tension like the above-mentioned measuring method, the detector for detecting the yarn tension in the yarn winding machine M requires high detection sensitivity. To be done. However, in order to increase the detection sensitivity,
When the natural frequency of the tracing stylus 3 of the tension detector 1 is brought close to the traverse frequency, there is a problem that resonance easily occurs. The output waveform from the tension detector 2 when it is not resonating (when the vibration damping means is not provided) is, for example, as shown in FIG.
It becomes like. In the graph of the figure, the horizontal axis represents time, the vertical axis represents the output value from the tension detector 2, and the tension signal output from the tension detector 2 is plotted. The tension signal is represented as a waveform obtained by adding a long wavelength component (hereinafter referred to as a fundamental frequency component) indicated by a chain double-dashed line to a short wavelength waveform (hereinafter referred to as a harmonic component) indicated by a solid line in the graph. . The long-wavelength component is a component in which the tracing stylus 3 fluctuates only by the traversing motion of the yarn, and has a correlation with the tension of the yarn S.

The waveform of the tension signal when resonance occurs (when the vibration damping means is not provided) is as shown in the graph of FIG. As a result of the stylus 3 resonating with the traverse motion of the yarn S, the harmonic component increases, and the magnitude of the signal output exceeds the detectable range (electrical or mechanical measurable range) of the tension detector 2. It may exceed. When this happens,
Output that exceeds the detectable range will be cut, so
It becomes impossible to detect the fundamental frequency component, and it becomes impossible to accurately detect the yarn tension.

Therefore, in the present invention, the tension detector 2 is provided with the vibration damping means D to suppress the resonance of the probe 3, and the probe 3
The amplitude of the signal is reduced so that the magnitude of the signal output does not exceed the detectable range of the tension detector 2. That is, the output waveform as shown in FIG. 6 is changed as shown in FIG.
The maximum output is set to be within the detectable range.

[0023]

According to the present invention, the tension detector of the yarn winding machine is provided with the vibration damping means for damping the vibration component added to the tracing stylus by the natural frequency of the tracing stylus itself. By reducing the rigidity of the stylus to increase the sensitivity of the detector, the natural frequency of the stylus is reduced, and even if the stylus is easily affected by its own resonance frequency, vibration damping means Can damp the vibration due to the natural frequency of the probe, and suppress the vibration component due to the natural frequency in the detection signal. That is, it is possible to put the output of the tension detector within the detectable range,
Accurate tension detection can be executed by a highly sensitive tension detector, and thus the present invention can realize precise tension control using a highly sensitive tension detector in the yarn winding process.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of an example of a yarn winding machine to which a tension detector according to the present invention is applied.

FIG. 2 is a perspective view showing a traverse fulcrum guide and an embodiment of a tension detector according to the present invention as taken out.

3A and 3B show an embodiment of a tension detector according to the present invention, wherein FIG. 3A is a plan view of a state in which a vibration damping means is cross-sectional, and FIG. 3B is a side view of the same state.

FIG. 4 shows another embodiment of the tension detector according to the present invention, and is a plan view of a state in which vibration damping means is sectioned.

FIG. 5 is a graph showing a tension signal waveform output from a tension detector (when a vibration damping unit is not provided).

FIG. 6 is a graph showing a tension signal waveform output from a tension detector (when a vibration damping unit is not provided) at the time of resonance.

FIG. 7 is a graph showing a tension signal waveform output from a tension detector provided with vibration damping means at the time of resonance.

[Explanation of symbols]

1 ... Traverse fulcrum guide 2 ... Tension detector 3 ... Measuring element
4 ... Holder part 5 ... Shaft part 6 ... Support D ... Vibration damping means M ... Yarn winding machine S ... Yarn T ... Traverse device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kinzo Hashimoto             Murata Machine, 136 Takeda Mukoyo-cho, Fushimi-ku, Kyoto             Machine Co., Ltd. Headquarters factory (72) Inventor Shu Yoshikawa             Murata Machine, 136 Takeda Mukoyo-cho, Fushimi-ku, Kyoto             Machine Co., Ltd. Headquarters factory F term (reference) 2F051 AA16 AB09 CA01

Claims (3)

[Claims] 1. A support body and a measuring element swingably supported by the support body, wherein the measuring element is engaged with a yarn to be traversed between a traverse fulcrum and a traverse device. A tension detector configured to detect the tension of the yarn by detecting the variation of the tracing stylus with the traversing motion of the yarn, and the variation of the tracing stylus with the traversing motion of the yarn. Of these, the tension detector is provided with a vibration damping means for damping a vibration component added to the probe by the natural frequency of the probe. 2. The natural frequency of the tracing stylus is set higher than the traverse frequency band of the yarn, and the vibration damping means uses only the traversing movement of the yarn among the fluctuations of the tracing stylus. The tension detector according to claim 1, wherein the vibration component added to the probe due to the natural frequency of the probe is attenuated more than the vibration component. 3. The vibration damping means is a rubber member provided so as to straddle the probe and the support.
The tension detector described in.