CZ2019810A3 - Method of reducing friction between the drawing belt of a textile machine for preparing fibres for spinning and / or for spinning staple yarns, the drawing device of the textile machine and the textile machine - Google Patents

Abstract

In a method for reducing friction between a drawstring of a textile machine for preparing fibers for spinning and / or spinning staple yarns, in which the drawstring (2) is driven by a drive roller (4) and further the drawstring (2) wraps around the static component device (1), the tension strap (2) rubs against the outer surface of the movable sliding element (6). By friction, it drives a movable sliding element (6), which rubs against the static component (7) of the drawing device (1) with its inner surface. The drawing device of a textile machine for preparing fibers for spinning and / or for spinning staple yarns on a textile machine comprises at least one drawing strap (2) wrapped around a drive roller (4) and around at least one static component (7) of the drawing device (1). A movable sliding element (6) is inserted between the at least one tensioning strap (2) and the at least one stationary component (7) of the tensioning device (1). The solution further relates to a textile machine for the production of a yarn comprising at least one yarn drawing device (1).

Description

Method for reducing friction between the drawstring of a textile machine for preparing fibers for spinning and / or for spinning staple yarns, the drawing device of a textile machine and a textile machine

Field of technology

The invention relates to a method for reducing friction between a drawstring of a textile machine for preparing fibers for spinning and / or spinning staple yarns, in which the drawstring is driven by a drive roller and the drawstring further encircles the static component of the drawing device.

The invention also relates to a drawing device of a textile machine for preparing fibers for spinning and / or for spinning staple yarns on a textile machine, comprising at least one stretching belt wrapped around a drive roller and around at least one static component of the drawing device.

The invention also relates to a textile machine with a drawing device.

Prior art

One of the basic textile technological processes in the production of staple yarns is the refining of a ribbon or strand of fibers by drawing in a drawing device. For this purpose, a stretching device is commonly used, equipped with one or two stretching straps, which are driven by rollers and pass through a static element, the so-called bridge, or a tensioning element at the fiber exit, which can be installed both inside and outside the stretching. strap of the drawstring. The requirements for the properties of stretch straps are considerable and often contradictory. The stretch strap must guide the stretched textile fibers well, which is ensured by the optimal coefficient of friction of the outer layer of the stretch strap, and must have a suitable coefficient of friction of the inner layer against the drive roller so that there is no slippage on this roller. However, in contrast to this requirement, it is desirable that the coefficient of friction of the tension belt relative to the static components through which the belt passes be low enough to ensure low abrasion and thus sufficient life of both the tension belt and these static components of the tension device.

This problem is solved in a number of documents, eg EP1350871 or CN103469388, which solve this discrepancy by designing a multi-component stretch strap, the outer surface of which is coarser and the inner surface together with the surface of static elements is realized with as low mutual friction coefficient. Utility model DE102005056534 also discloses a stretch strap with different outer and inner surfaces, wherein the outer surface is structured to guide the fibers well and the inner surface has a reduced coefficient of friction so as to be well guided over the static components of the stretch device.

EP0407715 (DE3922507) also solves this problem by means of a stretch strap consisting of several layers with different properties, the reinforcing layer also forming an inner smooth layer for movement on the static elements of the stretching device.

DE102006030155 (also published as WO2008000451) seeks a compromise solution where the surface of the tension strap would be suitable both for guiding the fibers and for sliding on the metal stable components of the tension device. An advantage is the possibility of rotating the drawstring depending on the type of spun fibrous material.

DE2407118 discloses a solution for a stretch strap for a flute, where there is a fabric inside the strap and both surfaces of which are covered by a layer of microporous polyurethane film. The file does not deal with the solution of friction of the tension strap and static components of the tension device.

-1 CZ 2019 - 810 A3

DE19730098 describes a longitudinally oriented structure of protrusions and grooves on the surface of a tension strap with a depth of less than 0.5 mm for guiding the strand fibers.

DE10029301 describes different inner surfaces of a stretch belt for sliding on stable components of the stretch device and for the drive roller, the sliding surface having a lower coefficient of friction and being located midway between the surfaces with a higher coefficient of friction for the drive roller. It is obvious that the production costs for such a complicated construction of the stretch strap are considerable. The operational disadvantage of this solution is that the compromise width of both types of surfaces may be insufficient for the required function.

The new features of the solution according to DE102005056534, ES2303429, consist in that the upper drawstring has a structured surface at least on the outside and the inner side of the upper drawstring is made of a material freely slidable over the stable components of the drawstring.

CN104975387 describes the placement of rubber balls in the openings of the stretch strap to reduce friction on the inside of the stretch strap.

Despite a certain reduction in friction between the strap and the static components of the stretching device, which the described state of the art brings is a common disadvantage of the above-described prior art complicated and expensive production of multicomponent straps consisting of different layers, not only in the belt thickness direction strap, but also the use of small rubber balls located in the holes of the drawstring.

The object of the invention is to eliminate or at least minimize the disadvantages of the prior art, in particular to eliminate the need for multicomponent straps to reduce friction between the tension strap of the tension device and the static components of the tension device.

The essence of the invention

The object of the invention is achieved by a method of reducing the friction between the drawstring of a textile machine for preparing fibers for spinning and / or spinning staple yarns, the essence of which consists in rubbing the outer surface of a movable sliding element by this friction. which rubs against the static component of the drawing device with its inner surface.

By inserting an independent (separate) movable sliding element between the inner surface of the tensioning strap and the static component of the tensioning device. This sliding element moves together with the tensioning belt, being driven only by compression between the inner surface of the tensioning belt and the surface of the respective static component of the tensioning device, without this sliding element encircling the drive roller of the tensioning belt. It is fully sufficient if the sliding element is arranged only around the respective static component, which it does not even have to enclose tightly around its entire circumference. The advantage of such a solution is the transfer of friction between the inner surface of the tensioning strap and the static component of the tensioning device to the point of contact of the sliding element and this static component of the tensioning device, which makes it possible to adjust the material of the drawstring and the required friction coefficient of the outer surface of the drawstring by which the drawstring is in contact with the textile fibers, but also the required friction coefficient of the inner surface of the drawstring and the outer surface of the stretcher roller driving the drawstring. This solution therefore makes it possible to make the stretch strap as is customary and has long been proven for textile technology, while optimizing the friction between the individual parts of the stretch device at a very low cost. The advantage of this solution is also a longer service life of the stretch strap due to its lower wear by abrasion on static elements.

- 2 EN 2019 - 810 A3 (components) of the tensioning device, because the tensioning belt, on its inner side, only rolls on the drive roller and on the sliding element without friction between the inner surface of the tensioning belt and the outer surface of the static component (parts) of the drawing device. This reduction in the cost of the stretch strap, together with the extension of its service life, compensates for the additional costs of manufacturing and assembling the inserted sliding element, whose dimensions (length) are significantly smaller than the dimensions (length) of the stretch strap and can also be made by simple technology. as a single material strap, eg PTFE, low friction fiber fabric, fiber reinforced composite material, etc.

From the point of view of force transmission, it is advantageous if the movable sliding element is frictionally driven by pressing the movable sliding element between the tensioning strap and the static component of the tensioning device.

From the point of view of the function and limitation of frictional heating of the stretcher belt, it is advantageous if the movable sliding element moves at a speed close to or equal to the speed of the inner surface of the stretcher belt as it is carried by the stretcher belt.

Therefore, it is advantageous if there is more friction between the movable sliding element and the tension strap than between the movable sliding element and the static component of the tensioning device.

The essence of the drawing device of a textile machine for preparing fibers for spinning and / or spinning staple yarns on a textile machine, which comprises at least one stretching strap wrapped around a drive roller and around at least one static component of the drawing device is between and a movable sliding element is inserted by at least one stationary component of the drawing device.

From a production and functional point of view, it is advantageous if the movable sliding element is formed by a movable closed strip.

The movable sliding element has a low coefficient of friction against the surface of the stationary component, which is advantageous for minimizing mutual friction.

From a material point of view, it is advantageous if the movable sliding element is made of PTFE or is made of a fabric made of fibers with a low coefficient of friction or is made of a composite.

From the point of view of the function and maintenance of the geometry of the drawing device, it is advantageous if the movable sliding element has a thickness in the range of 0.1 mm - 2 mm.

In order to reduce the guide faults of the movable sliding element, it is advantageous if the movable sliding element extends in the region outside the contact with the inner surface of the tension strap by at least one auxiliary guide element.

To effectively reduce friction, it is advantageous if the movable sliding element has a width in the range from 0.8 - 1.2 times the width of the tension strap.

For use in textile engineering, it is advantageous if at least one yarn drawing device according to the invention is used on a textile yarn production machine or on a ring or jet spinning machine.

By applying the invention, the friction of the tension strap around the static components of the tension device is dramatically reduced. The invention also increases the uniformity and quality of the spun yarn, reduces electricity consumption and reduces heat loss. It is thus possible to use a smaller motor to drive the drawing device, which has a favorable effect on the cost of manufacturing a textile machine, etc.

-3GB 2019 - 810 A3

Explanation of drawings

The invention is illustrated in the drawings, in which Fig. 1 shows a stretching device according to the invention with a movable sliding element, Fig. 2 shows a stretching device according to the invention with a movable sliding element and a belt tensioner, Fig. 3 shows a movable sliding element separately outside the stretching device 4 shows the arrangement of the tension strap, the movable sliding element and the static component of the tension device.

Examples of embodiments of the invention

The invention will be described on the basis of exemplary embodiments of a drawing device 1 of a fiber strand 8 for preparing fibers for spinning and / or for spinning staple yarns on a textile machine. The textile machine comprises at least one work station, but usually comprises a number of work stations arranged next to each other.

A drawing device 1 of the fiber strand 8 is arranged at the work station. The drawing device 1 of the fiber strand 8 comprises an inlet A of the fiber strand 8 and an outlet B of the fiber strand 8. In the drawing device 1 of the fiber strand 8, the fiber strand 8 is stretched between the inlet A of the fiber strand 8 and the outlet B of the fiber strand 8 and the thus prepared fiber strand 8 is further used in the yarn production process, e.g. in the case of a drawframe a strand of 8 fibers is placed in unspoken strand cans, in the case of a rovingframe the elongated strand 8 of fibers is wound on a spool (so-called spinning), or in the case of a machine for producing staple yarn this elongated strand of 8 fibers is twisted into staple yarn (mechanically at ring spinning machine, air nozzle in the case of an air spinning machine, etc.).

Between the inlet A of the fiber sliver 8 and the outlet B of the sliver 8, the drawing device 1 comprises at least one movable drawing belt 2, which is wrapped around the driven drive roller 4 and further guided through a static component 7 of the drawing device most - bridge. Between the inner surface of the tension strap 2 and the outer surface of the static component 7 of the tension device 1, a movable sliding element 6 is arranged (inserted), which encloses at least part of the circumference of the static component 7, extending outside the drive roller 4, i. is not wrapped around the drive roller 4. The movable sliding element 6 separates the tension strap 2, resp. its inner surface, from the static component 7, resp. its outer surface, ie. that the movable sliding element 6 is a barrier preventing mutual contact of the inner surface of the tension strap 2 and the outer surface of the static component 7 of the tensioning device 1. By moving the drive roller 4, the tension strap 2 moves the direction in which the tension strap moves 2.

The source of movement of the movable sliding element 6 is thus exclusively friction between the inner surface of the tension strap 2 and the outer surface of the sliding element 6 at the point where the strap 2 and the element 6 pass through the static component 7 of the tension device 1. of the sliding element 6 and the tension strap 2. In the exemplary embodiment shown in FIG. strap 2, so that the inner surface of the sliding element 6 abutting the outer surface of the static component 7 of the stretching device 1 frictionally moves along the outer surface of the static component 7. In the exemplary embodiment shown in Fig. 2 this is in the region where the inner surface of the sliding element 6 abuts the outer surface of the static component 7 of the stretching device 1 (bridge) and the outer surface of the tensioning element 9, and at the same time where the inner surface of the sliding strap 2 rests on the outer surface of the sliding element 6, so that the inner surface of the sliding element 6

-4GB 2019 - 810 A3 abutting the outer surface of the static component 7 of the stretching device 1 and the outer surface of the tensioning element 9 frictionally moves along the outer surface of the static component 7 and the tensioning element 9. For the remainder of its length, the movable sliding element 6 defined by the inner surface of the tension belt 2 and the outer surface of the drive roller 4, the sliding element 6 either not subjected to any stress in this area and therefore not subject to wear or encircling part of the outer surface of at least one auxiliary guide element (not shown) to limit possible uncontrolled behavior of the movable sliding element 6. in the area out of contact with the inner surface of the tension strap 2.

The movable sliding element 6 is, for example, formed by a closed (endless) strap of shorter length, resp. shorter circumferential lengths than the length (circumferential length) of the tension strap 2. The movable sliding element 6 is for example formed as a single layer of a single material, e.g. PTFE, or is made of a low friction fiber fabric, or is made of a composite or it is made of a composite with fiber reinforcement, etc., eg it consists of a PTFE strap with an integrated textile net inside, etc.

The width h of the movable sliding element 6 basically corresponds to the width of the tension strap 2, resp. ideally it ranges from 0.8 - 1.2 times the width of the tension strap 2. To maintain the geometry and functionality of the tension device 1, the thickness t of the movable sliding element 6 ranges from 0.02 mm to 2 mm.

In the embodiment of the tensioning device 1 in Figs. by this pair of assemblies (2, 4, 6, 7, 20, 40, 70) a pair of secondary rollers 5 is arranged.

In an embodiment (not shown), a movable sliding element 6 is also inserted between the auxiliary strap 20 and the auxiliary static component 70.

The invention is ideally used on a textile machine for the production of a roving or on a ring or jet spinning machine.

Industrial applicability

The invention can be used in all textile machines for refining a continuous structure of staple fibers, such as a fiber ribbon, a fiber strand, etc., in which at least one stretch strap is used in the drawing device. These are mainly, but not exclusively, a twisting machine, a flugelhorn, an annular spinning machine and a jet spinning machine.

Claims (14)

PATENT CLAIMS A method for reducing friction between a stretch belt of a textile machine for preparing fibers for spinning and / or for spinning staple yarns, in which the draw belt (2) is driven by a drive roller (4) and further the draw belt (2) surrounds the static component (7). of the stretching device (1), characterized in that the stretching strap (2) rubs against the outer surface of the movable sliding element (6), by this friction drives the movable sliding element (6), which rubs against the static component (7) with its inner surface. stretching device (1). Method according to claim 1, characterized in that the movable sliding element (6) is frictionally driven by pressing the movable sliding element (6) between the stretching strap (2) and the static component (7) of the stretching device (1). Method according to Claim 1 or 2, characterized in that the movable sliding element (6) moves at a speed close to or equal to the speed of the inner surface of the tension strap (2) as it is carried by the tension strap (2). Method according to any one of claims 1 to 3, characterized in that there is more friction between the movable sliding element (6) and the stretching strap (2) than between the movable sliding element (6) and the static component (7) of the stretching device (1). A drawing device of a textile machine for preparing fibers for spinning and / or for spinning staple yarns on a textile machine, comprising at least one drawing strap (2) wrapped around a drive roller (4) and around at least one static component (7) of the drawing device (1), characterized in that a movable sliding element (6) is inserted between the at least one tensioning strap (2) and the at least one stationary component (7) of the tensioning device (1). The drawing device of a textile machine according to claim 5, characterized in that the movable sliding element (6) is formed by a movable closed strip. Stretching device according to Claim 5 or 6, characterized in that the movable sliding element (6) has a low coefficient of friction with respect to the surface of the stationary component (7). Stretching device according to Claim 7, characterized in that the movable sliding element (6) is made of PTFE. Stretching device according to Claim 7, characterized in that the movable sliding element (6) is formed by a fabric of fibers with a low coefficient of friction or is formed by a composite. Stretching device according to one of Claims 5 to 9, characterized in that the movable sliding element (6) has a thickness in the range from 0.02 mm to 2 mm. Stretching device according to one of Claims 5 to 10, characterized in that the movable sliding element (6) extends in the region outside the contact with the inner surface of the stretching strap (2) by at least one auxiliary guide element (9). Stretching device according to one of Claims 5 to 11, characterized in that the movable sliding element (6) has a width in the range from 0.8 to 1.2 times the width of the stretching strap (2). A textile machine for the production of a yarn comprising at least one yarn drawing device (1) formed according to any one of claims 5 to 12. -6GB 2019 - 810 A3 An annular or jet spinning machine comprising at least one roving drawing device (1) formed according to any one of claims 5 to 12.