RU2493304C2 - Method of mechanical shrinkage of textile material - Google Patents

Abstract

FIELD: textiles, paper.

SUBSTANCE: method lies in covering by the textile material of the heated cylindrical surface of the shrinking shaft and in contact with the branch of the rubber strap under load covering it in an arc. The load on the textile material in the area of its contact with the cylindrical surface of the shrinking shaft and the rubber strap is carried out by power amplitude phase-frequency influence with the power alternating frequency $$v=\frac{{\upsilon }_1}{l}+\frac{k\cdot A}{m\cdot {\upsilon }_2},$$

where v is the power alternating frequency, υ₁ is speed of movement of the textile material, l is pace of the weft threads, k=k₁+k₂ is the given stiffness coefficient of the system, k₁ is the stiffness coefficient of the belt, k₂ is the stiffness coefficient of the textile material, A is the amplitude of the power influence, m is the given mass of the system "shrinking shaft - loading mechanism", υ₂ is the speed of the power influence. The speed of movement of the textile material in the shrinkage area is maintained less than 2…6% of the speed of the textile material before the shrinkage area and after it. For influence on the textile material in the area of its contact with the cylindrical surface of the shrinking shaft and the rubber strap, the means for dynamic pulse loading is used, made in the form of an electromechanical transducer.

EFFECT: increased efficiency of shrinkage due to reduction of frictional forces between the threads in the area of shrinkage and in the area of the contact of the shrinking shaft and the rubber strap.

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Description

The invention relates to the textile industry and can be used in finishing industries on fabric shrink machines of various types.

A known method of shrinkage of tissue, carried out using a device for mechanical shrinkage (USSR Author's Certificate No. 125536, class 8b, 33. A device for mechanical shrinkage of fabric / A.I. Shchegolev, B.A. Vorobyov, M.V. Belyakov. - No. 615504/28; decl. 02.01.1959; publ. 1960 g, Bull. No. 2. - 2 pp .: ill.), Namely, that the fabric to be processed is passed through a work clamp formed by an endless elastic web and a smooth metal seating shaft , after the passage of which she mechanically shrinks; while the overall tension and lateral deformation of the elastic web affecting the shrinkage are carried out by movements of the tension and clamping shafts, respectively.

The disadvantages include the fact that this method entails rapid wear of the elastic web due to the use of intensive static loads between the clamping and seating shafts that are unevenly distributed over the working width of the machine to ensure the required percentage of fabric shrinkage.

A known method of shrinkage of fabric (USSR Author's Certificate No. 1567693, MKI D06C 21/00, Method of shrinkage of fabric / Yu.G. Fomin, I.A. Kiselev, A.G. Sviridov, S.V. Belov. - No. 4328890/31 -12; decl. 17.11.87; publ. 05.30.90, Bull. No. 20. - 3 pp .: ill.), Namely, that the fabric is moistened, and then steamed by holding the front side of the fabric on a heated cylindrical surface, covered by an arc of a branch of a rubber belt under load; when steaming the fabric, it is additionally carried out on the wrong side along an additional cylindrical surface, covered along the arc by the other branch of the rubber belt under load; moistening the fabric is carried out in two stages, first from the front side, and then before additional steaming from the wrong side, while the load on the rubber belt is not more than 0.6 kN / linear. cm.

The disadvantage of this method is the wear of the rubber belt that is uneven over the working width of the machine, as well as the inability to control and regulate the level of shrinkage of textile material.

The prototype is a fabric shrink method (Pat. RU 2090681 (C1) Russian Federation, IPC D06C 21/00, Fabric shrink method and device for its implementation / Fomin Yu.G., Sokolov A.S .; applicant and patentee Ivanovskaya state text, academy. - No. 94031671/12; application. 30.08.94; publ. 09/20/97, Bull. No. 26. - 6 pp., ill.), which consists in moistening and steaming the fabric first from the front, then from the wrong side and moreover, before moistening and steaming the fabric, the adjustment is made by covering the sitting shafts with the fabric at an angle depending on the density of the fabric, and during moistening and tissue pairing carry out separate adjustment of the load on the fabric at each edge, depending on the deviation of the shrinkage of the fabric from a given value.

The disadvantages of this method include: low operational life of the rubber belt due to uneven wear in the working width due to the bending deformation of the drive shaft from the transverse static load; a negative effect on the physicomechanical properties (reduction in consumer properties) of shrinkable textile material subjected to previous finishing operations (for example, dressing) due to its double-sided steaming; high power consumption of the drive of the system due to the creation of a static technological load expended on the rotation of the seating and clamping shafts.

The technical result of the claimed invention is to increase the efficiency of shrinkage by reducing frictional forces between the threads in the area of shrinkage (the contact zone of the seating shaft and rubber belt).

The specified technical result is achieved by the fact that in the method of shrinkage of textile material, which consists in covering textile material with a heated cylindrical surface of a seating shaft and in contact with a branch of a rubber belt covering it in an arc under load, according to the invention, the load on the textile material in the area of its contact with the cylindrical the surface of the seating shaft and rubber belt carry out power amplitude-frequency impact with a frequency of change of force

, $$v=\frac{{\upsilon }_{\mathrm{one}}}{l}+\frac{\mathrm{to}\cdot A}{m\cdot {\upsilon }_2}$$

,

where v is the frequency of change of force, υ ₁ is the speed of movement of the textile material, l is the pitch of the weft threads, k = k ₁ + k ₂ is the reduced coefficient of rigidity of the system, k ₁ is the coefficient of rigidity of the rubber belt, k ₂ is the coefficient of rigidity of the textile material , A is the amplitude of the force impact, m is the reduced mass of the “seating shaft - loading mechanism” system, υ ₂ is the speed of the force impact, while the speed of movement of the textile material in the shrink zone is kept at 2 ... 6% of the speed of the textile material to the shrink zone and after her to act on the textile material in its area of contact with the cylindrical surface of the shaft and the shrinkable rubber belt used means for dynamic impulsive loading, formed, e.g., in the form of an electromechanical transducer.

The shrinkage process is carried out as a result of changes in the structural parameters of the textile material due to the relative movement of the weft threads along the warp, thereby increasing the surface density of the textile material.

Increasing the surface density, we reduce to the maximum the step (distance) between the weft threads.

The system "seat shaft - textile material - rubber belt - drive shaft" (figure 2) is in a stress-strain state under the influence of both normal q _n stresses and tangential q _τ . These stresses cause both transverse and longitudinal deformations of the rubber belt and textile material located in the contact zone between the seating and drive shafts.

Since the system "rubber belt - textile material" is a rheological characteristics of an elastic-viscous system (Kukin, G.N. Textile materials science (fibers and threads): a textbook for universities / G.N. Kukin, A.N. Soloviev, A.I. Koblyakov; under the editorship of G.N.Kukin, Doctor of Technical Sciences; - 2nd ed., Revised and additional - M .: Legprombytizdat, 1989. - 352 pp .: ill. ISBN 5 -7088-0198-0), then the weft threads of the fabric of textile material passing through the AC zone are exposed to the force field, the tangent components of which cause them (threads) to relative displacements e along the main threads in the direction of movement of the web, which is the purpose of the compaction process - mechanical shrinkage, which occurs on the geometrical slip arc of the aircraft with the previous arc of rest AB, where the magnitude of the seating force is greater than the resistance of the material to it. Reducing the tension of the textile material at its entrance into the contact zone with the seating shaft and rubber belt provides a reduction in resistance to its seating force, the value of which largely determines the percentage of shrinkage. The pulsed loading mode of the system in the shrink zone and the decrease in tension at the entrance to this zone provides a decrease in the resistance to the longitudinal movement of the weft threads by reducing the friction forces between them and the warp threads, which are determined by normal pressure forces arising from the interaction of interwoven warp and weft threads. In this case, the elastic component of direct deformation of the main thread decreases, and the elastic-viscous properties of the main thread are added to it. One of the main factors that increase the efficiency of the shrinkage process under pulsed loading is a decrease in the friction force between the threads compared to the resting friction force, which is characteristic of methods and devices that implement the static mode of loading of the shrink zone, i.e. where the clamping shaft and rubber belt interact with the seating shaft with a fixed static load in magnitude and direction.

Thus, a decrease in the tension of textile material and the use of alternating dynamic loads on it in the contact zone of the seating shaft and rubber belt provide the shrinkage process with a higher intensity (efficiency) and ultimately with a high percentage of shrinkage.

Figure 1 presents a diagram of the implementation of the proposed method. Figure 2 shows a diagram of the interaction of the elements of the system "seating shaft - textile material - rubber belt - drive shaft".

The method is implemented on the shrinkage line LU-180 when processing fabric "flannel art.1640", consisting of 85% cotton and 15% viscose, having a working width of 150 cm and a surface density of 180 g / m ² .

From the tentering machine, textile material 1 was supplied to the roller 2 of the lever compensator 3 with the pneumatic cylinder 4, reducing its tension by changing the operating speeds of the machine. The lever compensator 3 synchronized the working speeds of the shrink machine and the previous machine as follows: the movement speed of the textile material 1 in the shrink zone was kept at 2 ... 6% of the speed of the textile material 1 to the shrink zone of the AC and after it, as a result of which the tension of the textile material was reduced. With a decrease in speed of less than 2%, the influence of the pulsed loading mode practically does not affect the efficiency of the shrinkage process. When the speed decreases by more than 6%, the longitudinal tension decreases sharply, as a result of which stability of transportation of textile material along the working bodies of the fabric shrinker is lost, which contributes to a sharp displacement of the fabric of textile material relative to the center line of the machine, as a result of which breaks of the fabric, its winding on rotating machine parts and uneven feeding into the shrinkage zone of the speakers. In addition, an excess of speed by an amount greater than 6% will lead to slipping ("chewing") of the textile material in the shrink zone and the formation of a moiré effect (folds) on it. The shrinkage zone of the AC is formed by the heated surface of the seating shaft 5 and the rubber belt 6 along the arc of their contact.

At the moment of passage of the textile material 1 along the AC arc, a load was applied to it, carried out by power amplitude-frequency-frequency action, using a means for dynamic pulsed loading, which is, for example, a link 7, pivotally connected to the rod 8 of the pneumatic cylinder 9, on the piston of which vibrations from an electromechanical transducer act . In this case, the frequency of change in force was determined by mathematical expression

, $$v=\frac{{\upsilon }_{\mathrm{one}}}{l}+\frac{\mathrm{to}\cdot A}{m\cdot {\upsilon }_2}$$

,

where v is the frequency of change of force, υ ₁ is the speed of movement of the textile material, l is the pitch of the weft threads, k = k ₁ + k ₂ is the reduced coefficient of rigidity of the system, k ₁ is the coefficient of rigidity of the rubber belt, k ₂ is the coefficient of rigidity of the textile material , A is the amplitude of the impact of the force, m is the reduced mass of the "seating shaft - loading mechanism" system, υ ₂ is the velocity of the force.

Depending on the structural characteristics of the fabric being processed and the operating speed of the machine, the operation of the dynamic pulsed loading facility was set up, and during the design and construction, its technological characteristics were determined depending on the range of structural characteristics of the processed textile material. For the processed fabric “flannel art.1640”, consisting of 85% cotton and 15% viscose, having a working width of 150 cm and a surface density of 180 g / m ² at a speed of movement of 10 ... 30 m / min in the shrink zone, the weft location step threads of 0.49 mm, the given coefficient of rigidity of the system is 21.8 · 10 ⁶ N / m, the amplitude of the force 1.5 mm, the reduced mass of the “seating shaft - loading mechanism” 350 kg and the speed of the force 0.52 ... 1, 53 m / s, the frequency of the change in force generated by the dynamic pulsed loading means, after substitution in the above the mathematical expression, when the speed of movement of textile material in the shrink zone of 10 m / min and the speed of the force 0.52 m / s was 525 Hz, and with an increase in the speed of the textile material and the force to 3 Ohm / min and 1.53 m / s respectively - 1.08 kHz.

The warp threads, with less tension, allowed the weft threads to move between them in the structure of the textile material with greater ease due to the reduction of the friction forces between them (threads).

The shrinkage of the textile material occurred in the AC zone of its contact with the heated surface of the seating shaft 5 and the branch of the rubber belt 6 due to its entry on the stretched (zone AB) and output on the compressed (zone BC) fibers of the latter, as well as exposure to the system with alternating loads by means for dynamic loading. In the pulsed loading mode of textile material in the shrinkage zone of the AS in the structure of its filaments, there was already the presence of the friction force between the filaments, less than the static friction force in statically loaded systems (in the prototype and all known fabric shrink machines). Due to this, the shrinkage process was ensured more intensively and at lower loads.

The drive of the drive shaft 10 was carried out using an electric motor. The tension shaft 11 was able to move along the guides, setting the longitudinal tension of the rubber belt 6 and the angle of coverage of the seating shaft 5.

Claims (1)

The method of mechanical shrinkage of textile material, which consists in covering textile material with the heated cylindrical surface of the seating shaft and in contact with the branch of the rubber belt covering it in an arc under load, characterized in that the load on the textile material in the area of its contact with the cylindrical surface of the seating shaft and rubber belt carry out power amplitude-frequency exposure with a frequency of force change $$v=\frac{{\upsilon }_{\mathrm{one}}}{l}+\frac{\mathrm{to}\cdot A}{m\cdot {\upsilon }_2},$$

where v is the frequency of change of force, υ ₁ is the speed of movement of the textile material, l is the pitch of the weft threads, k = k ₁ + k ₂ is the reduced coefficient of rigidity of the system, k ₁ is the coefficient of rigidity of the rubber belt, k ₂ is the coefficient of rigidity of the textile material , A is the amplitude of the force impact, m is the reduced mass of the “seating shaft - loading mechanism” system, υ ₂ is the speed of the force impact, while the speed of movement of the textile material in the shrink zone is kept at 2 ... 6% of the speed of the textile material to the shrink zone and after her to act on the textile material in its area of contact with the cylindrical surface of the shaft and the shrinkable rubber belt used means for dynamic impulsive loading, formed, e.g., in the form of an electromechanical transducer.

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