SU1409902A1 - Device for checking quality of textile and jersey fabric - Google Patents

Abstract

This invention relates to equipment for quality control of textile and knitted fabrics. The purpose of the invention is to increase the reliability of the device and increase the transmittance of the optical system. The device contains a laser, a scanning unit consisting of a deflecting optical system and a micro-lens, a glass fiber unit, several projection lenses, a receiving unit consisting of two receiving systems located above and below the controlled sheet, a phase inverter, a field detection circuit. the frequency of the pulse, the adder, the controlled phase inverter, and the information processing unit. The device is capable of controlling the quality of the material both in transmitted and reflected light, is resistant to misalignments and has a high transmittance of the optical system. The parameters of the device (the number of projection lenses, their focal lengths, the size of the laser beam, etc.) are optimized with respect to the geometric dimensions and the speed of movement of the controlled web. The claims contain a mathematical expression relating the specified parameters. S Il. § SL

Description

The invention relates to textile and knitting machinery and can be used for sorting textile and knitted fabrics, as well as to determine the presence of defects in other long materials.

The purpose of the invention is to increase the reliability of the device and the accuracy of control by increasing the transmittance of the optical system.

FIG. Figure 1 shows the optical layout of the device; in fig. 2 shows a section A-A in FIG. 1 (the face surface of the divider); in fig. 3 - signal processing circuit.

The device for quality control of textile and knitted fabrics contains a laser I, a scanning unit 2 consisting of a deflecting optical system 3, a micro-lens 4 and an electric motor 5, a divider 6 consisting of several fiberglass fibers 7, forming a light beam optical system 8, consisting of several projection lenses 9, receiving unit 10, consisting of receiving optical systems I and 12, located above and below the controlled web 13 and consisting of several similar lenses 14, photodetectors 15 and Preamplifiers 16 and 17 connected with them, phase inverter 18, pulse polarity detection circuit 19, totalizer. ra 20, controlled (phase inverter 21, and information processing unit 22

The device works as follows.

A beam of light from laser 1 (Fig. I) is directed to a rotating optical deflecting system 3 rigidly connected to the micro-lens 4. In this case, the laser radiation axis is aligned with the rotation axis of the electric motor 5. The optical system 3 deflects the light beam 180 and directs it to the microscope lens 4. The last one focuses the laser radiation. In this case, the focal plane of the micro-lens 4 is aligned with the plane in which the input ends of the fiber-glass bundles 7 of the divider b are located. The centers of the glass-fiber bundles 7 of the divider .6 are located around a circle, the radius R of which is equal to the distance between the axis of rotation of the electric motor 5 and the optical

the axis of the micro-lens 4 and is determined by the formula

R-Kf / Arf :: f.XL-) ck R-KWI- TL 1 G

where K is the number of projection lenses of the optical system forming the light beam; off focal distance of projection lenses; A - relative aperture of projection lenses; - device resolution; 0 — laser radiation divergence;

U is the diameter of the laser beam; Jb - increase in projection lenses;

L is the width of the controlled material;

 - the speed of movement of the light spot in the plane of the controlled web; VP is the speed of movement of the controlled web.

When the scanning unit 2 is rotated, the light spot formed by the microscope lens 4 moves along the input ends of the fiberglass bundles 7. At the same time, it also moves like along the output ends of the fiberglass bundles 7 located in the subject planes of the projection lenses 9 which are equally spaced apart from each other in the direction perpendicular to the direction of movement of the monitored web 13, and in the planes of the images of these lenses combined with the surface of the monitored web 13,

The amount of movement of the light spot in the plane of the monitored material 13 is determined by the light size of the fiberglass bundle 7 and a given increase in the projection lenses 9. The size of the light spot formed in the control plane is determined by the divergence of the laser radiation, the focal distance of the microobjective 4 and the project magnification: lenses 9 of the light beam forming optical system 8 are selected so that the laser beam can be scanned across the entire width of the monitored m material 13.

The receiving system 11 is located above the web 13 and controls the quality of the material in reflected light.

The receiving system 11 consists of several lenses 14 spaced at equal distances from each other, and photo receivers 15 optically coupled with them, the outputs of which are connected to the preamplifier 16. The objective planes of the lenses 14 are aligned with the surface of the test sheet 13, Photodetectors 15 are installed in the flat bones of the images.

The number of lenses 14, the dimensions of the light-sensitive areas of the photoreceivers 15 are chosen so that the entire width of the web 13 is monitored. The receiving system 12 of the receiving unit 10 is located under the material 3 and controls its quality in transmitted light. Receiving system 12 consists of several lenses I4 and photodetectors 15 (in receiving systems P and 12, the same objectives and photoreceivers are used).

The lenses 14 of the receiving system 12 are located coaxially with the lenses 14 of the receiving system P. Since the angles of incidence of the scanning light beam constantly change with time, the indicatrices of the reflected beam and the light passing through the material are also permanently changed. The indicatrices of both reflected and transmitted light beams are diffusely directed, and the qualitative characteristics of the indicatrices of

The controlled phase inverter 21 changes the polarity of the incoming to it. the information input of the signal only when a signal arrives at its control input from the circuit 19 for determining the p45 field

(i.e., the nature of the distribution of the reflected or transmitted through the material of the high-voltage pulse, the input of which is connected to the energy in the angle) are the same as for the output of the amplifier 16 receiving signal for the reflected, as well as for the transmitted light beams and radiation pattern of the scanning beam.

Thus, in the absence and field of view of the receiving unit 10 of defective areas of the surface of the monitored material 13, the level of the signals at the outputs of the receiving systems 1 and 12 constantly synchronously changes. Synchronously change the electric signals from the outputs of the receiving systems 11 and 12 are fed to the adder 20. In the latter, the signals are subtracted. At the output of the adder 20, the signal level is constant and independent of

Subjects P. In turn, the pulse polarity detection circuit 19 generates a control signal only when negative polarity pulses arrive at its input,

In the case where the linear density of the defective area is less than the nominal density of the material, a negative impulse appears at the output of the body 16. Phase inverter 18 reverses the phase of the signal, and a positive nm-pulse is applied to the input of the adder. At the same time, a negative impulse appears at the output of the pre-usnlitel 17 of the receiving system 12.

55

angles of incidence of the scanning light beam.

0

five

0

five

All defects of textile and knitted fabrics can be divided into two groups: defects whose linear density exceeds the nominal linear density of the material (compaction) and defects whose linear density is less than the nominal density of the material (discharge, hole).

When a defective sections of the web 13 appear in the field of view of the receiving unit 10, impulses appear at the outputs of receiving systems P and 12. Moreover, in the case when the linear density of the defective area exceeds the nominal, the output of the pre-16 receiving system 11 is a positive polarity pulse, which through the phase inverter 18 enters the input of the adder 20.

The phase inverter I8 changes the phase of the signal to the opposite only when pulses of negative polarity arrive, and therefore to the input of the adder. positive impulses are coming. At the same time, a negative polarity pulse arrives at the second input of the adder 20 at the output of the preamplifier 17 of the receiving system 12. After subtracting the signals at the input of the adder 20, a pulse is generated, which through the controlled phase inverter 21 enters the input of the information processing unit 22.

The controlled phase inverter 21 changes the polarity of the incoming to it. the information input of the signal only when the signal from the circuit 19 for determining the polarity of the pulse, whose input is connected to the output of the amplifier 16 of the receiving signal, arrives at its control input

pulse, the input of which is connected to the output of the amplifier 16 of the receiving signal

Subjects P. In turn, the pulse polarity detection circuit 19 generates a control signal only when negative polarity pulses arrive at its input,

In the case where the linear density of the defective area is less than the nominal density of the material, a negative impulse appears at the output of the vehicle 16. Phase inverter 18 reverses the phase of the signal, and a positive nm-pulse is applied to the input of the adder. At the same time, a negative impulse appears at the output of the pre-usnlitel 17 of the receiving system 12.

After subtracting the signals at the output of the adder 20, a signal is formed.

| positive polarity, which goes to the information input of the control- JMoro phase inverter 21. At the same time | the control input of the phase inverter 21 receives a signal from the circuit 19 for determining the polarity of the pulse. The phase inverter 21 changes the polarity of the incoming signal, and a negative polarity pulse is fed to the input of the information processing unit.

The proposed design of a device for controlling the quality of textile and knitted fabrics ensures the stability of the output signal level, which improves the accuracy of the device and simplifies the information processing circuit.

Claims (1)

Invention Formula A device for controlling the quality of textile and knitted fabrics, containing a successively installed and optically coupled laser, a scanning unit, a light beam divider, a optical system that forms a healthy light beam, and a receiving unit including a set of lenses that are optically connected - photo-detectors, connected to an information processing unit, characterized in that, in order to increase device reliability and control accuracy by increasing the optical transmittance c) I, the scanner node Vanilla is made in the water of a rotating deflecting system; optically connected to the micro lens, the light beam divider is a block consisting of glass fiber bundles whose entrance torques are installed in the focal plane of the micro lens on a circle with a diameter D, the output ends of the glass bundles are optically coupled to the light beam forming optical This system, implemented as a system of parallel-mounted K projection lenses, the receiving unit is positioned as two receiving systems located above and below the control sheet and includes a phase inverter, a pulse polarity detection circuit, an adder and a phase inverter controlled the output of the receiving system located under the canvas is connected to one of the inputs of the adder, the output of the receiving system located above the canvas through a phase inverter is connected to the second input of the adder, the output of which is connected It is connected with the Information input of the controlled phase inverter, the input of the phase inverter is connected to the control input of the controlled phase inverter, the output of which is connected to the information processing unit, through the pulse polarity detection circuit, and the value D is equal to -Kfo, f fAJ-6 (t-tl. ± 1: lii J U „ where K is the number of projection lenses of the shape of the light beam of the optical system; fgj is the focal distance of the projection lenses; A - relative aperture of projection lenses; сГ- device resolution; c - divergence of laser radiation; L is the diameter of the laser beam; Ji- an increase in projection lenses; L is the width of the controlled web; USD is the speed of movement of the light spot in the plane of the controlled web; Y is the speed of movement of the controlled web. I 1 4-A g / e.2 Compiled by V. Kalechits Editor I. Casarda Tehred L.Oliynyk Order 3470/39 Circulation 847 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Fi.Z Proofreader M. Pojo Subscription