CN207331159U - The device of on-line checking ring throstle spinning tension - Google Patents

Abstract

The utility model relates to a device for online detection of spinning tension of a ring spinning frame, which is characterized in that it includes a force sensor, a position sensor, a CPU and a voltage-stabilized power supply; The yarn plate is installed on the horizontal side of the yarn guide plate lifting rod of the spinning machine by the base, and the force sensor can detect the vertical force at the yarn guide plate and the horizontal force perpendicular to the installation surface of the yarn guide plate; the position sensor is arranged on the base, It is used to detect the position of the yarn guide plate; the output end of the force sensor and the position sensor is connected to the signal acquisition unit, and the signal acquisition unit collects the output signals of the force sensor and the position sensor, and the output end of the signal acquisition unit is connected to the filter amplifier, A/ D converter and CPU, CPU obtains tension data according to the detection data of force sensor and position sensor. The utility model can carry out non-contact measurement to the dynamic tension of the sliver in the ring spinning process.

Description

On-line detection device for spinning tension of ring spinning frame

technical field

The utility model relates to a device for on-line detection of spinning tension of a ring spinning frame, which belongs to the technical field of spinning.

Background technique

Ring spinning is the yarn forming process of drafting, twisting and winding process on roving. tension on the segment. Usually, the area from the rear bell mouth (or rear roller nip) to the front roller nip is called the drafting area of the yarn, and the area from the front roller nipper to the yarn guide hook is called the yarn sliver. The twisting area; the high-speed rotating arc-shaped sliver from the guide hook to the traveler is called the balloon area of the sliver; the area from the traveler to the winding point on the high-speed rotating spindle is called the sliver winding area. In the process of ring spinning, the spinning tension in a broad sense refers to the tension on the sliver in the twisting zone, balloon zone and winding zone, which are called sliver tension in the twisting zone, sliver tension in the balloon zone and Sliver tension in the winding area can also be referred to as spinning tension, balloon tension and winding tension respectively. Spinning tension in a narrow sense refers to the tension on the sliver in the twisting section; the balloon tension is further divided into the tension at the top of the balloon and the tension at the bottom of the balloon. Generally, during the twisting process of one revolution of the spindle, the winding process of one level of the bobbin and the spinning process of one doffing, due to the lifting movement of the yarn guide plate and the program plate during the spinning process, at the same time, the height and shape of the balloon, The winding radius of the bobbin changes all the time, so the tension on the yarn sliver changes dynamically. Since the ring spinning system is a flexible and nonlinear processing system rotating at high speed, it is generally believed that the factors affecting the change of spinning tension should include the spindle speed, the height and shape of the balloon, the fineness of the sliver, the position of the program plate and the position of the tube. Yarn winding radius, traveler weight and other factors, the change of spinning tension on the sliver during spinning is the result of nonlinear coupling and interaction of the above factors, so the change of tension on the sliver during spinning is An extremely complex problem of mechanics and nonlinear mathematics.

Because in the production process of yarn and fabric, the yarn tension value is too large or its fluctuation value exceeds the allowable range, which will cause spinning breakage. Yarn breakage rate is an important index to measure yarn quality, which affects the output, quality and worker stand ability of spun yarn. Therefore, measuring the yarn tension during the production process and controlling the change of the yarn tension in a balanced manner will become a necessary condition for realizing high-speed and high-efficiency spinning and black lamp spinning. On-line detection of spinning tension of ring spinning frame is an important subject in the progress of ring spinning technology.

Domestic and foreign researchers mainly focus on the following two points in their research on the above problems: ① establish a mechanical model, combine differential geometry to mathematically analyze the sliver tension and its variation in the spinning process, and predict the spinning tension and its variation; ②Digital measurement technology can measure the spinning tension online and in real time during the actual spinning process.

In the 1980s, Professor Chen Renzhe, Department of Mechanical Engineering, East China Institute of Textile Engineering, created the theory of yarn mechanics. Taking the balloon formed during the twisting and winding process of spinning as the research object, he established a model and mathematical analysis method to analyze the tension of the balloon. , The formation of the balloon shape and its control have been perfectly analyzed, and the quantitative analysis of the balloon tension and its influencing factors can be carried out, and the accurate prediction of the balloon shape change, etc., but it needs to be verified by experimental means.

For the experimental test of spinning tension, the contact measurement method is generally used to measure the sliver tension in the twisting section at present, but the tension in the balloon section and the tension in the winding section cannot be measured. When using the contact method to measure yarn tension, the hand-held full-digital yarn tension meter senses the yarn tension through the movable guide wheel located in the middle of the two fixed guide wheels. Since the guide wheel is in direct contact with the yarn, it not only adds additional The friction also changes the movement state of the sliver, thereby changing the original shape of the balloon and the original spinning state. This kind of contact measurement will cause large errors, the measurement results cannot be copied, and it is not suitable for long-term on-line detection, so there are many problems.

Contents of the invention

The purpose of the utility model is to overcome the deficiencies in the prior art and provide a device for on-line detection of the spinning tension of the ring spinning frame, which can perform non-contact measurement of the dynamic tension of the sliver during the ring spinning process.

According to the technical solution provided by the utility model, the device for online detection of the spinning tension of the ring spinning frame is characterized in that it includes a force sensor, a position sensor, a CPU, and a voltage-stabilized power supply; the force sensor is embedded in a guide On the yarn plate, the yarn guide plate is installed on the horizontal side of the yarn guide plate elevating rod of the spinning frame by the base, and the force sensor can detect the vertical force at the yarn guide plate and the horizontal force perpendicular to the installation surface of the yarn guide plate; the position sensor is set On the base, it is used to detect the position of the yarn guide plate;

The output end of described force sensor and position sensor connects signal acquisition unit, and signal acquisition unit gathers the output signal of force sensor and position sensor, and the output end of signal acquisition unit connects filter amplifier, A/D converter and CPU successively, and CPU according to force Tension data is obtained from the detection data of the sensor and the position sensor.

Further, a display unit is also included, and the display unit is connected to the CPU.

The device for online detection of the spinning tension of the ring spinning frame described in the utility model studies the dynamic tension of the sliver in the ring spinning process and its non-contact measurement method, and establishes a new system oriented to the ring spinning system. Yarn tension online detection device, which detects the dynamic stress at the yarn guide plate in real time. The dynamic change law of yarn tension. Combining real-time dynamic monitoring with the solution of physical-mathematical equations, the twisting process of one rotation of the spinning spindle, the winding process of one level of the bobbin and the tension of the sliver in the twisting area during the spinning process of one doffing, Instantaneous change of sliver tension in the balloon area and sliver tension in the winding area.

Description of drawings

Fig. 1 is a functional block diagram of the device for online detection of spinning tension of a ring spinning frame according to the present invention.

Fig. 2 is a structural diagram of the device for online detection of the spinning tension of the ring spinning frame according to the present invention.

Fig. 3 is a working flow chart of the device for online detection of the spinning tension of the ring spinning frame according to the present invention.

Fig. 4 is a schematic diagram of dynamic force analysis at the yarn guide hook in the coordinate system constructed by the yarn guide hook and the yarn guide plate.

Fig. 5 is a schematic diagram of force analysis at the yarn guide hook and the yarn guide hook in the coordinate system constructed by the program.

Figure 6 is a schematic diagram of the force analysis of the yarn guide hook.

Fig. 7 is an enlarged view of I in Fig. 6 .

Fig. 8 is a schematic diagram of Q _y variation curve.

Fig. 9 is a schematic diagram of the position corresponding to the rotation of the balloon.

Detailed ways

Below in conjunction with specific accompanying drawing, the utility model is further described.

The current spinning process is shown in Figure 2. The sliver is fed from the back roller 1, drawn by the middle roller 2 to the grip of the front roller 3, the sliver is twisted by the yarn guide hook 8, and the spindle 7 rotates to drive the program 6 Rotating on the traveler 11 to form a balloon, the program plate 12 lifts up and down, and finally winds up on the bobbin 10. During spinning, the spinning section is formed between the front roller and the yarn guide hook, and the tension on the yarn is called spinning tension T _f ; the balloon section is formed between the yarn guide hook and the traveler, and the tension on the yarn is respectively T _q is the tension at the top of the balloon and T _r is the tension at the bottom of the balloon; the winding section is formed between the traveler and the bobbin.

In order to be able to realize the automatic detection of the spinning tension of the ring spinning frame, four functional requirements need to be met: first, the device is stable and does not affect the jointing, doffing and cleaning work of employees; second, the signal is automatically collected with the change of spinning tension Spinning equipment; the third is to process the collected signal and convert the data output function; the fourth is to obtain the test results to display on the screen, print or apply to control the spinning tension of the whole machine. According to the above four functions, the overall scheme shown in Figure 1 is formulated, as shown in Figure 1 and Figure 2, the device for online detection of the spinning tension of the ring spinning frame described in the present invention includes a force sensor, a position sensor, and a signal acquisition unit , filter amplifier, A/D converter, CPU, display unit, and regulated power supply; wherein, the force sensor 5 is embedded on the yarn guide plate 9, and the yarn guide plate 9 is installed on the yarn guide plate of the spinning frame by the base 4. On the horizontal side of the bar, the working performance is the same as that of other yarn guide plates on the same table; the force sensor can realize the automatic collection of tension change signals, and is used to detect the vertical force at the yarn guide plate and the horizontal force perpendicular to the installation surface of the yarn guide plate. Under the joint action of the tension T _f and the tension T _q at the top of the balloon during twisting and winding, when the moving yarn passes through the yarn guide plate, a force is applied to the yarn guide plate. Since the yarn guide plate and the force sensor are integrated, the yarn guide plate The received force generates a signal through the force sensor; the position sensor is arranged on the base 4, and the position sensor detects the position of the yarn guide plate, and the output voltage signal of the force sensor and the position sensor is collected by the signal acquisition unit and passed through the A/D converter Perform conditioning conversion, then read the measured data by the CPU, and display it on the display unit; the stabilized power supply is used to supply power to the CPU and the like.

The working principle of the device for online detection of the spinning tension of the ring spinning machine described in the utility model: when the yarn passes through the yarn guide plate, the tension force will be applied to the yarn guide plate, and the force sensor and the position sensor will be deformed, resulting in a change with the force. The position sensor outputs an analog voltage signal that changes with the position of the yarn guide plate; the analog voltage signal is filtered and amplified, and then converted into a digital signal that is convenient for CPU processing through the A/D converter. The digital signal is output to the CPU for operation to form a tension signal source. The CPU outputs such results to the display unit to display the results according to keyboard commands and programs.

The principle of the method for online detection of the spinning tension of the ring spinning frame is described below.

(1) Dynamic real-time detection method of the force on the yarn guide plate in the spinning process:

As shown in Figure 4, set the center of the yarn guide hook as point O, take the X axis as the horizontal line passing through point O and parallel to the installation surface of the yarn guide plate, and take the Y axis as the line passing through point O and perpendicular to the installation surface of the yarn guide plate As for the horizontal straight line, the Z axis is taken as the vertical line passing through the O point and perpendicular to the X-O-Y plane, thereby constructing the X-Y-Z three-dimensional space coordinate system with the center of the yarn guide hook as the origin. Let the contact point between the force sensor and the yarn guide plate be O', take the straight line passing through the contact point O' and parallel to the X axis as the X' axis, take the straight line passing through the contact point and the extension line of the Y axis as the Y' axis, and take The Z' axis is a vertical line parallel to the Z axis and perpendicular to the X'-O'-Y' plane, thereby constructing the X'-Y'-Z' three-dimensional space coordinate system with the contact point O' as the origin.

The dynamic force analysis at the yarn guide hook is composed of the yarn guide hook 8, the yarn guide plate 9, and the force sensor 5. The force sensor is subjected to force and undergoes information conversion, and finally the results displayed on the display unit are F _{Z measured} , F _{Y measurement} , F _{Z measurement} is the vertical force at the yarn guide plate, F _{Y measurement} is the horizontal force perpendicular to the installation surface of the yarn guide plate. The projection of the support force Q on the Z axis at the yarn guide is Q _Z : namely

Q _Z = F _{Z measure} (1).

(2) Detection method of sliver tension in twisting area, sliver tension in balloon area, and sliver tension in winding area:

As shown in Figure 5, set the center of the yarn guide hook as point O, take the X-axis as the horizontal line passing through point O and parallel to the installation surface of the yarn guide plate, and take the Y-axis as the line passing through point O and perpendicular to the installation surface of the yarn guide plate As for the horizontal straight line, the Z axis is taken as the vertical line passing through the O point and perpendicular to the X-O-Y plane, thereby constructing the X-Y-Z three-dimensional space coordinate system with the center of the yarn guide hook as the origin. Let the center of the program be O', the straight line passing through the program center O' and parallel to the X axis is the X' axis, and the straight line passing through the program center and parallel to the Y axis be the Y' axis, thus constructing X'-Y'- Z three-dimensional space coordinate system.

As shown in Figure 5, assume that the angle between the yarn in the twisting section and the Y axis is γ, the angle between the top balloon tangent and the Z axis is β, and the intersection point between the bottom of the balloon and the program traveler is P, then O' The angle between P and the X' axis is α. In Fig. 6 and Fig. 7, R represents the radius of the front roller; h represents the distance from the center of the front roller to the horizontal plane of the machine; Ya represents the distance from the center of the front bottom roller to the center of the yarn guide hook; γ represents the yarn guide angle; Z _x is the position sensor The reading value is the distance from the yarn guide plate to the horizontal plane of the machine; the fixed value of h is 95mm, Ya is 73.8mm, and R is 15mm.

Among them, the angle between the twisted segment yarn and the Y axis is γ,

The angle between the top balloon tangent and the Z axis is β,

Let T _f be the spinning tension, T _q the tension at the top of the balloon, and Q the supporting force of the guide hook, then it can be known from the force balance principle:

Let the projections of the support force Q at the guide hook on the X, Y, and Z axes be Q _x , Q _y , and Q _z respectively, and project formula (1) on the X, Y, and Z axes respectively, and we can get:

Q _x - T _q sin β cos α = 0 (5);

Q _y -(T _q sinβsinα+T _f cosγ)=0 (6);

Q _z - T _q cos β + T _f sin γ = 0 (7);

Solving formulas (2), (3) and (4) simultaneously, we can get:

Q _x =T _q sinβcosα (8);

Q _y = T _q sin β sin α + T _f cos γ (9);

Q _z = T _q cos β + T _f sin γ (10);

From Euler's formula:

T _f =T _q e ^-μσ (11);

In the formula: μ is the dynamic friction coefficient between the yarn and the yarn guide hook; σ is the enveloping angle between the yarn and the yarn guide hook, which is related to the yarn guide angle and the top angle of the balloon.

Substituting formula (8) into formula (7), we can get:

The spinning tension T _f is:

The top tension T _q of the balloon is:

Also known from the basic theory of the balloon, the relationship between the tension Tq at the top of the balloon and the tension _Tr at the bottom of the balloon is:

In the formula: R _g is the program radius; m is the linear density of the balloon yarn; ω is the angular velocity of the balloon rotation (generally, it can be expressed approximately by the angular velocity of the spindle rotation);

Substituting formula (14) into formula (15), the tension T _r at the bottom of the balloon can be obtained as:

Appropriate winding tension is the basis for ensuring the quality of the package. The tension T _r at the bottom of the balloon is transmitted upward to the bottom of the balloon after the winding tension T _ω overcomes the frictional resistance between the sliver and the traveler. The relationship between the two is generally expressed as:

T _ω = KT _r (16);

In formula (16), K is the ratio of the winding tension T _ω to the tension T _r at the bottom of the balloon, referred to as the tension ratio. The experimental data of the tension ratio of the different cross-sectional shapes of the traveler wire are shown in Table 1:

Table 1 Tension ratio of different cross-sectional shapes of traveler wire

Bringing formula (16) into (17), the winding tension T _ω can be obtained as:

(3) Real-time detection method of spinning tension, balloon tension and winding tension during one balloon rotation process, one winding level process and the whole doffing process:

(a) Judgment of the rotating position of the balloon:

From Q _y =T _q sinβsinα+T _f cosγ, T _q sinβ and T _f cosγ can be regarded as constants in the process of one balloon revolution, and because α=ωt ₁ , t ₁ is the balloon revolution time; then Q _y It can be regarded as a sine function about the rotation angle of the spindle, as shown in Figure 8, and the corresponding position of the balloon rotation is shown in Figure 9. When the balloon rotates to the P ₂ position, the measured Q _y is the largest, and when the balloon rotates to the P ₄ position, the measured Q _y is the smallest, and the actual value of the balloon is obtained by judging from the measured Q _y value spectrogram. The law of rotation (the speed of the balloon rotation, the position of the balloon rotation).

(b) Determination of maximum tension and minimum tension during balloon rotation:

When the balloon rotates to the P ₂ position, the measured Q _y is the largest, Q _ymax =T _q sinβ+T _f cosγ, when the balloon rotates to the P ₄ position, the measured Q _{y is} the smallest, Q _ymin =- T _q sin β + T _f cos γ. From this, it can be obtained that the values of Q _z , β, γ and σ when the balloon rotates to position P ₂ and position P ₄ are substituted into formula (12) - formula (17), and the spinning tension, Balloon tension, winding tension.

(c) Setting of data collection density:

Assuming that the rotation speed of the spindle is 18,000 rpm, the data collection density is set to n times or 1/n times the rotation speed of the balloon, so as to ensure the repeatability of the detection points and the reproducibility of the data. Then, when measuring the spinning tension in a balloon rotation process, the data collection density can be set to 1-4 times/rotation, that is, 18000-72000 times/min; when measuring the spinning tension in a winding level process During tension, the data collection density can be set to 1-2 times/rev, that is, 18000-36000 times/min; when measuring the spinning tension during the whole doffing process, the data collection density can be set to 1 time/rev. Turn, that is, 18000 times/min.

Embodiment two:

Spin 20 counts of pure cotton yarn, the spindle speed is 12846r/min, when measuring the spinning tension during one balloon revolution, the data collection density is set to 1 time/rev, that is, 12846 times/min; measure a winding level process When the spinning tension is in the middle, the data collection density can be set to 1 time/rev, that is, 12846 times/min; when the spinning tension in the whole doffing process is measured, the data collection density can be set to 1 time/rev , namely 12846 times/min.

As shown in Figure 7, when the yarn guide plate is at the lowest position, Z _x =0.038332, the fixed value of h is 95mm, Y _a is 73.8mm, and R is 15mm. The test tension is F _{Z measurement} = 2.15cN, F _{Y measurement} = 7.51cN.

Depend on Available: γ=59.33°;

Depend on It can be obtained: β=15.96°.

It can _be seen from literature that the coefficient of dynamic friction between the yarn sliver and the guide hook is μ=0.26; the range of σ is 1-2°, 1° is _taken ;

Therefore,

The program radius R _g is 21mm; the linear density m of the balloon yarn is 18.5tex; the balloon rotation angular velocity ω is 12846r/min; the ratio K of the winding tension T _ω to the tension T _r is 1.5.

Depend on Available:

It can be obtained from T _ω =KT _r : T _ω =1.5×7.01=10.52cN.

Table 2 Results of Online Collection of Spinning Tension of Ring Spinning Frame

Claims (2)

1. A device for online detection of the spinning tension of a ring spinning frame, characterized in that it includes a force sensor, a position sensor, a CPU, and a voltage-stabilized power supply; the force sensor is embedded on the yarn guide plate (9), The yarn guide plate (9) is installed on the horizontal side of the yarn guide plate lifting rod of the spinning frame by the base (4), and the force sensor can detect the vertical force at the yarn guide plate and the horizontal force perpendicular to the installation surface of the yarn guide plate; the position The sensor is arranged on the base (4) for detecting the position of the yarn guide plate; The output end of described force sensor and position sensor connects signal acquisition unit, and signal acquisition unit gathers the output signal of force sensor and position sensor, and the output end of signal acquisition unit connects filter amplifier, A/D converter and CPU successively, and CPU according to force Tension data is obtained from the detection data of the sensor and the position sensor. 2. The device for online detection of the spinning tension of the ring spinning frame according to claim 1, further comprising a display unit connected to the CPU.