A method and equipment for testing and measuring the twist of elastic slub yarn

Abstract

This invention discloses a method and equipment for testing and measuring the twist of elastic slub yarn. The method involves applying tension to the elastic slub yarn using a blackboard winch, winding it around a blackboard, and then placing it under a video microscope to measure the twist angle and diameter. The twist is then calculated using a formula. This method solves the problem that traditional twist measurement methods can only measure the average twist of elastic slub yarn. The equipment includes an automatic tension-adjustable winch and a measuring device. The automatic tension-adjustable winch is equipped with two yarn guides, a tension regulator, a force sensor, a calibration blackboard, and a reduction gearbox. The measuring device includes an adjusting slide, a blackboard track, a video microscope lens, and a video microscope display screen. This invention can test the twist of different parts of elastic slub yarn under different tensions and the twist variation patterns, standardize relevant standards for determining the twist parameters of elastic slub yarn, and provide a basis for evaluating the mechanical properties of elastic slub yarn and testing fabric forming. The steps are simple and save time and costs.

Description

Technical Field

[0001] This invention relates to a method and equipment for testing and measuring the twist of elastic slub yarn. Background Technology

[0002] Elastic slub yarn uses elastic yarn as the core yarn and is wrapped with one or more fibers. Twist is an important indicator of yarn structure. Due to overfeeding, elastic slub yarn experiences an imbalance of torsional force between yarns. In order to balance the applied pressure and stabilize the shape of the elastic yarn, the twist of elastic slub yarn will slip laterally. The twist transmission results in a larger twist in the base yarn and uneven twist distribution between the slub and the base yarn.

[0003] Currently, traditional methods for measuring yarn twist include the direct counting method and the untwisting and retwisting method, which are suitable for filaments, staple fibers, and plied yarns. The fiber tracer twist angle method is suitable for slub yarns. However, it has the following limitations when used to measure elastic slub yarns:

[0004] (1) Elastic slub yarn has resilience. In order to make the yarn straight and not stretch, the pre-tension should be greater than that of ordinary yarn. The tension value cannot be automatically adjusted and controlled.

[0005] (2) During the direct counting method measurement, the untwisting stops when the set number of twists is reached. Manual operation is required to completely untwise. During the untwisting process of elastic slub yarn, there is a torsional force to balance the external pressure of the yarn. Finally, it can be unwound until the elastic yarn is parallel to the yarn, but the twist is the average value and cannot distinguish the twist of slub, transition and base yarn sections.

[0006] (3) The twist measured by the untwisting and retwisting method is larger than the actual twist and is the average value, which cannot distinguish the twist of the slub, the transition and the base yarn section;

[0007] (4) The fiber tracer twist method is lengthy and limited to AB color spun slub yarn. Summary of the Invention

[0008] To solve the above-mentioned technical problems, the present invention provides a simple structure, easy operation, and a method and device for testing the twist of elastic slub yarn, which can be used to test the twist of various parts of elastic slub yarn; it can also measure the twist variation of elastic slub yarn under an automatic tension regulator.

[0009] The technical solution adopted in this invention is as follows: a twist testing device for elastic slub yarn, comprising an automatic tension regulating yarn winch and a measuring device; the automatic tension regulating yarn winch is equipped with two yarn guides, a tension regulator, a calibration blackboard, and a reduction gearbox; the tension regulator is located between the two yarn guides, each of which is equipped with a force sensor, and the tension regulator is equipped with a tension measuring sensor; the calibration blackboard is mounted on a blackboard support, and the reduction gearbox is connected to the calibration blackboard for driving the rotation of the calibration blackboard; the calibration blackboard is equipped with a millimeter scale; the measuring device includes an adjusting slide, a blackboard track, and a video microscope lens, the blackboard track is mounted on the adjusting slide, the adjusting slide is used to adjust the position of the blackboard track, the blackboard track is located directly below the video microscope lens, and the video microscope lens is electrically connected to the video microscope display screen.

[0010] In the aforementioned elastic slub yarn twist testing device, the adjusting slide includes a mounting base and a slide. The mounting base is provided with a slide groove I, and a knob hole I is provided on the side wall of the slide groove I. A knob I is provided inside the knob hole, and a gear I is provided at the inner end of the knob I. A slider I is provided at the bottom of the slide and is placed in the slide groove I. A rack I is provided at the bottom of the slider I, and the rack I meshes with the gear I. The slide is provided with a slide groove II, which is perpendicular to the slide groove I. A knob hole II is provided on the side wall of the slide groove II and a knob II is provided inside the knob hole. A gear II is provided at the inner end of the knob II. A slider II is provided at the bottom of the blackboard guide and is placed in the slide groove II. A rack II is provided at the bottom of the slider II, and the rack II meshes with the gear II.

[0011] In the aforementioned twist testing equipment for elastic slub yarn, knobs I and II are micrometer knobs.

[0012] The aforementioned twist testing equipment for elastic slub yarn also includes a machine base, on which the yarn guide, tension adjuster, blackboard bracket, adjusting slide, video microscope lens, and video microscope display screen are mounted.

[0013] In the aforementioned twist testing equipment for elastic slub yarn, the tension regulator includes a force-measuring guide wheel, a swing guide rod, and a tension regulator base. The swing guide rod is mounted on the tension regulator base via bearings, and the guide wheel is mounted on the cantilever end of the swing guide rod. The tension regulator base is mounted on the machine base.

[0014] A method for measuring the twist of elastic slub yarn using the aforementioned twist testing equipment includes the following steps:

[0015] 1) Prepare the sample and conditioned it;

[0016] 2) Determine the parameters of the automatic tension regulating yarn winnowing machine: blackboard size 250×220mm; winnowing speed adjustment range is 10-400r / mm; multiple yarns are distributed per centimeter of blackboard length for yarn winding; the pre-tension value is set and adjusted to half the elastic yarn number;

[0017] 3) Place the sample on the yarn tube shaft, pull the yarn end of the sample through the yarn guide, tension device, and finally fix it on the calibration blackboard; drive the calibration blackboard to rotate and wind the yarn;

[0018] 4) After completing the yarn winding, remove the calibration blackboard and fix it in the blackboard track. Adjust the objective lens magnification until the image clearly shows the yarn's slant. Compare the magnified value on the display screen with the actual millimeter scale value on the blackboard. If the difference is <0.1mm, the selected objective lens magnification is accurate and the measurement data is usable.

[0019] 5) Measure the slub joint, transition section, twist angle, and diameter of the base yarn of the sample;

[0020] 6) After obtaining the twist angle and diameter of the elastic slub yarn, the corresponding twist of the slub and base yarn parts is calculated using the following formula;

[0021] ;

[0022] In the formula: β is the twist angle; d is the diameter, mm; h is the twist pitch, mm, h=100 / T; T is the twist degree, twist / 10cm.

[0023] In the above-mentioned method for testing the twist of elastic slub yarn, when conditioning the sample in step 1), the sample is conditioned for 24 hours under the standard atmosphere specified in GB / T6529.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This invention can test the twist of elastic slub yarn under different tensions, and analyze how the twist pattern of elastic slub yarn changes with tension, the twist distribution pattern of elastic slub yarn, and the influence of twist distribution on strength.

[0026] 2. This invention enables the measurement of the twist of elastic slub yarn, and the steps are simple, saving time and costs.

[0027] 3. This invention uses a video microscope to calibrate the blackboard, making the measurement integrated and the measurement data more accurate and reliable.

[0028] 4. The adjustable slide of this invention enables precise feeding of the blackboard track, controls the twist angle and diameter measurement of the slub, transition section and base yarn of elastic slub yarn, facilitates the integrity of the twist measurement of the entire yarn, and is used for style analysis of elastic slub yarn. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the twist testing device for elastic slub yarn of the present invention.

[0030] Figure 2 This is a three-dimensional schematic diagram of the automatic tension regulator of the present invention.

[0031] Figure 3 This is a schematic diagram of the video microscope calibration blackboard plane of the present invention.

[0032] Figure 4 This is a perspective view of the adjusting slide of the present invention.

[0033] Figure 5 This is a front view of the adjusting slide of the present invention.

[0034] Figure 6 This is a diagram illustrating the conversion principle of the twist formula for elastic slub yarn.

[0035] In the diagram: yarn tube 1, yarn guide 2, tension regulator 3, yarn guide 4, yarn guide force sensor 5, tension measurement sensor 6, force sensor 7, calibration blackboard 8, video microscope lens 9, adjusting slide 10, video microscope display screen 11, reduction gearbox 12, force-measuring yarn guide wheel 31, swing guide rod 32, tension regulator base 33, yarn winding clamp 81, millimeter scale 82, blackboard track 101, knob I 102, slide groove II 103, knob II 104. Detailed Implementation

[0036] The invention will now be further described with reference to the accompanying drawings.

[0037] like Figure 1-5 As shown, the present invention includes a base, an automatic tension-adjustable yarn winch, and a measuring device. The automatic tension-adjustable yarn winch includes a yarn guide 2, a yarn guide 4, a tension regulator 3, a calibration blackboard 8, and a reduction gearbox 12. The tension regulator 3 is located between two yarn guides 2. Force sensors 5 and 7 are respectively installed on the yarn guides 2 and 4, and a tension measuring sensor 6 is installed on the tension regulator 3. The tension regulator 3 includes a force-measuring yarn guide wheel 31, a swing guide rod 32, and a tension regulator base 33. The swing guide rod 32 is mounted on the tension regulator base 33 via bearings, and the yarn guide wheel 31 is mounted on the cantilever end of the swing guide rod 32. The tension regulator base 33 is mounted on the base. The pre-tension of the yarn is determined by the force sensors. When the yarn passes through the yarn guide wheel 31, the tension value exceeds or falls below the pre-tension. The magnitude of the tension can be initially determined by observing the left-right swing of the swing guide rod 32, with the specific force value displayed by the tension measuring sensor 6.

[0038] A calibration blackboard 8 is mounted on a blackboard support, and a reduction gearbox 12 is mounted on the blackboard support and connected to the calibration blackboard 8 to drive its rotation. The calibration blackboard 8 is equipped with a millimeter scale 82. The measuring device includes an adjusting slide 10, a blackboard guide 101, and a video microscope lens 9. The blackboard guide 101 is mounted on the adjusting slide 10 and is used to adjust its position. The blackboard guide 101 is located directly below the video microscope lens 9, which is electrically connected to the video microscope display screen 11. The yarn guide 2, blackboard support, adjusting slide 10, video microscope lens 9, and video microscope display screen 11 are mounted on a machine base.

[0039] The adjustable slide 10 includes a mounting base and a slide. The mounting base has a slide groove I105, and the side wall of the slide groove I105 has a knob hole I. A knob I102 is installed in the knob hole, and a gear I is installed at the inner end of the knob I102. A slider I is installed at the bottom of the slide and is placed in the slide groove I. A rack I is installed at the bottom of the slider I, and the rack I meshes with the gear I. The slide has a slide groove II, which is perpendicular to the slide groove I. A knob hole II is installed on the side wall of the slide groove II, and a knob II 104 is installed in the knob hole. A gear II is installed at the inner end of the knob II. A slider II 103 is installed at the bottom of the blackboard guide and is placed in the slide groove II. A rack II is installed at the bottom of the slider II, and the rack II meshes with the gear II. Knobs I and II are micrometer knobs.

[0040] The simulated yarn dynamic breaking strength testing method of the present invention includes the following steps:

[0041] 1) Prepare the sample and condition it to humidity; when conditioning the sample, condition it to humidity for 24 hours under the standard atmosphere specified in GB / T6529.

[0042] 2) Determine the parameters of the automatic tension regulating yarn winnowing machine: blackboard size 250×220mm; winnowing speed adjustment range is 10-400r / mm; multiple yarns are distributed per centimeter of blackboard length for yarn winding; the pre-tension value is set and adjusted to half the elastic yarn number;

[0043] 1) Place the sample on the yarn tube shaft 1, and pull the yarn end of the sample through the yarn guide 2, the force measuring yarn guide wheel 3, and the yarn guide 4, finally fixing it at the yarn clamp 81 of the calibration blackboard 8; drive the calibration blackboard 8 to wind the yarn;

[0044] 2) After completing the yarn winding, remove the calibration blackboard 8 and fix it in the blackboard track 101. Adjust the objective lens magnification until the image clearly shows the yarn's slant. Compare the magnified value on the display screen with the actual millimeter scale value on the blackboard. If the difference is <0.1mm, the selected objective lens magnification is accurate and the measurement data is usable.

[0045] 3) Adjust knob I 102 and knob II 104 to measure the slub joint, transition section, twist angle and diameter of the base yarn of the sample;

[0046] 4) By formula The twist of each part was calculated.

[0047] Following the above steps, randomly select 16 elastic slub yarns. s The twist of the -40D cone yarn was measured to be 72 twists per 10cm. －1 The measurement data are shown in Table 1;

[0048] The same yarn was tested on a Y3331LN digital yarn twist meter, and 20 sets of data were obtained using the direct counting method, as shown in Table 2. The average twist was 72.145 twists per 10 cm. －1 ;

[0049] The untwisting and retwisting method yielded 30 sets of data, as shown in Table 3. The average twist was 76.84 twists per 10 cm. －1 ;

[0050] The data clearly shows that the twist measured by the direct counting method is close to the set twist. The twist transmission of elastic slub yarn leads to uneven twist distribution between the slub and the base yarn. Similarly, during untwisting, the direct counting method causes transverse twist slippage to balance the applied pressure until the single yarn and elastic yarn are completely parallel. The number of untwisted twists then represents the twist within the length of the yarn sample. However, the untwisting and retwisting method yields a larger value than the elastic slub yarn twist measurement method. After untwisting and retwisting in the opposite direction, the twist count returns to the initial length. During retwisting, the elastic yarn becomes an uncontrollable factor. Based on the above principle analysis, the experimental data obtained from the above steps are usable.

[0051] Table 1 Measurement data of 16s-40D elastic slub yarn

[0052]

[0053] Table 2 Measurement data of 16s-40D direct untwisting method

[0054]

[0055] Table 3 Measurement data of 16s-40D untwisting and twisting method

[0056]

Claims

1. A twist testing device for elastic slub yarn, characterized in that: The device includes an automatic tension-regulating yarn winch and a measuring device. The automatic tension-regulating yarn winch has two yarn guides, a tension regulator, a calibration blackboard, and a gearbox. The tension regulator is located between the two yarn guides, each with a force sensor, and the tension regulator has a tension measurement sensor. The calibration blackboard is mounted on a blackboard support, and the gearbox is connected to the calibration blackboard for rotating it. The calibration blackboard has a millimeter scale. The measuring device includes an adjusting slide, a blackboard guide rail, and a video microscope lens. The blackboard guide rail is mounted on the adjusting slide and is used to adjust its position. The blackboard guide rail is located directly below the video microscope lens, which is electrically connected to the video microscope display screen. The tension regulator includes a force-measuring guide wheel, a swing guide rod, and a tension regulator base. The swing guide rod is mounted on the tension regulator base via bearings, and the guide wheel is mounted on the cantilever end of the swing guide rod. The tension regulator base is mounted on the machine base. The pre-tension of the yarn is determined by the force sensor. When the yarn passes through the guide wheel, the tension value exceeds or falls below the pre-tension. The magnitude of the tension can be initially determined by observing the degree of left and right swing of the swing guide rod. The specific force value is shown by the tension measuring sensor.

2. The twist testing device for elastic slub yarn according to claim 1, characterized in that: The adjustable slide includes a mounting base and a slide. The mounting base has a slide groove I, and the side wall of the slide groove I has a knob hole I. A knob I is installed in the knob hole, and a gear I is installed at the inner end of the knob I. A slider I is installed at the bottom of the slide and is placed in the slide groove I. A rack I is installed at the bottom of the slider I and meshes with the gear I. The slide also has a slide groove II, which is perpendicular to the slide groove I. A knob hole II is installed on the side wall of the slide groove II and a knob II is installed in the knob hole. A gear II is installed at the inner end of the knob II. A slider II is installed at the bottom of the blackboard guide and is placed in the slide groove II. A rack II is installed at the bottom of the slider II and meshes with the gear II.

3. The twist testing device for elastic slub yarn according to claim 2, characterized in that: The knobs I and II mentioned above are micrometer knobs.

4. The twist testing device for elastic slub yarn according to claim 1, characterized in that: It also includes a machine base, on which the yarn guide, tension adjuster, blackboard bracket, adjusting slide, video microscope lens and video microscope display screen are mounted.

5. A method for measuring the twist of elastic slub yarn using the twist testing device according to any one of claims 1-4, comprising the following steps: 1) Prepare the sample and conditioned it; 2) Determine the parameters of the automatic tension regulating yarn winnowing machine: blackboard size 250×220mm; winnowing speed adjustment range is 10-400r / mm; multiple yarns are distributed per centimeter of blackboard length for yarn winding; the pre-tension value is set and adjusted to half the elastic yarn number; 3) Place the sample on the yarn tube shaft, and pull the yarn end of the sample through the yarn guide, tension device, and finally fix it on the calibration blackboard; drive the calibration blackboard to rotate and wind the yarn; 4) After completing the yarn winding, remove the calibration blackboard and fix it in the blackboard track. Adjust the objective lens magnification until the image clearly shows the yarn's slant. Compare the magnified value on the display screen with the actual millimeter scale value on the blackboard. If the difference is <0.1mm, the selected objective lens magnification is accurate and the measurement data is usable. 5) Measure the slub joint, transition section, twist angle, and diameter of the base yarn of the sample; 6) After obtaining the twist angle and diameter of the sample, the corresponding twist of the slub and base yarn parts is calculated using the following formula; ； In the formula: β is the twist angle of the sample; d is the diameter of the sample, mm; T is the twist, twist / 10cm.

6. According to the twist test method of elastic slub yarn as described in claim 5, when conditioning the sample in step 1), the sample is conditioned for 24 hours under the standard atmosphere specified in GB / T6529.

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