RU2435877C1 - Carbon bundle spreading apparatus - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: apparatus for spreading a carbon bundle has series-arranged coiling unit 1, a pair of feed rolls 2, a unit for controlling 3 and regulating tension in the processed bundle, a unit for spreading 4 the carbon bundle with an air stream, a pair of receiving rolls 5, as well as a unit for winding 6 the spread bundle. The unit for spreading 4 the carbon bundle with an air stream is in form of two supporting rolls 11, 12 and a nozzle 13 which is installed between and under the supporting rolls with inclination angle of 30-70 to the displacement surface of the bundle, and is made with a flat slotted opening 14 with possibility of feeding compressed air through said opening. The slotted opening 14 of the nozzle 13 of the unit for spreading 4 the carbon bundle can be made with partitions 15. The nozzle can be fitted with possibility of regulating its inclination angle depending on the thickness of the bundle. ^ EFFECT: high speed of the stream of compressed air results in efficient splitting of the carbon bundle into monofilaments and obtaining a belt of carbon fibres with lower surface density. ^ 3 cl, 6 dwg

Description

The invention relates to the production of chemical fibers, in particular to the production of expanded carbon tows (eng. - spread tow), used for the manufacture of various fabrics, ribbons and prepregs. Composite materials made on the basis of expanded carbon tows have a denser packing of ribbons and fabrics with higher tensile strength. Due to the smaller thickness of the monolayer of the composite material based on straightened carbon tows, the stress concentration decreases due to the use of layers with different orientations, the stress concentration decreases due to the presence of holes, fillets, cavities, etc. In composite materials based on expanded strands, the shear strength and fracture toughness are higher than those obtained from traditional fabrics and tapes. At the same time, the use of expanded carbon bundles as part of fabrics and ribbons in the manufacture of carbon fiber reinforced plastics reduces the cost of products by using thicker carbon bundles to obtain materials with a low monolayer thickness, to obtain products that cannot be made from traditional fabrics and ribbons, for example, thin-walled ones, to use new opportunities in the manufacture of hybrid composite materials.

Closest to the claimed installation is a unit for straightening a carbon bundle, which contains sequentially located winding unit, a pair of feed rolls, a straightening unit of the carbon bundle by air flow, a pair of receiving rolls, a winding device for a straightened carbon bundle, and a control and regulation system for tensioning the processed carbon bundle (e.g., US Pat. No. 6,032,342, D01D 11/02, 2000).

The disadvantage of this installation is that the expansion of the carbon tow is carried out by air flow while passing the tow over the air path into which air is sucked in by a vacuum pump. Since the cross section of the air path is large, it is impossible to ensure a high air flow rate, which leads to a low degree of expansion of the carbon tow and the quality of the resulting material.

The objective of the invention is to increase the degree of expansion of the carbon tow and increase the width of the carbon tapes obtained by expanding the carbon tow by increasing the speed of the air flow.

The technical result is achieved through the installation for straightening a carbon tow, which contains sequentially located winding unit, a pair of feed rolls, a control unit for adjusting the tension of the processed bundle, a straightening unit of the carbon bundle by air flow, a pair of receiving rolls, as well as a winding unit of the straightened tow, the expansion of the carbon tow by air flow is made in the form of two support rolls and a nozzle, which is fixed between the support rolls and above them with tilted at an angle from 30 ° to 70 ° to the plane of movement of the tow and is made with a flat slotted hole with the possibility of supplying compressed air through it. Moreover, due to the high flow rates of compressed air, an effective separation of the carbon bundle into monofilaments and the production of carbon fiber tapes with a lower surface density are achieved.

The slit opening of the nozzle of the carbon tow expansion unit can be made with partitions.

The nozzle can be installed with the possibility of adjusting the angle of inclination depending on the thickness of the bundle.

The above features and advantages of the present invention will be clear from the following description of a preferred example of its implementation with reference to the accompanying drawings, in which the same positions are used to represent the same elements:

figure 1 presents a diagram of a plant for straightening a carbon tow in accordance with the present invention;

figure 2 is the same, a top view;

figure 3 - nozzle;

figure 4 - nozzle, view a of figure 3;

figure 5 - nozzle, view B of figure 3;

figure 6 is another example of a nozzle, view B of figure 3.

The installation for straightening the carbon bundle comprises a winding unit 1, behind which a pair of feed rolls 2, a unit 3 for controlling and regulating the tension of the processed bundle, an assembly 4 for expanding the carbon bundle by air flow, a pair of receiving rolls 5, and also a winding unit 6 are sequentially placed.

The winding unit 1 is made in the form of a holder for a transverse unwind reel equipped with a spring brake and mounted with the possibility of axial movement depending on the deviation relative to the 0-0 axis of the tow supplied through it (the axis of movement of the tow).

The feed rolls 2 are designed to feed and move the carbon tow to the node 4 of the expansion of the carbon tow by air flow. One of the feed rolls 2 (preferably the upper one) is made driven with the possibility of controlling the rotation speed depending on the tension force of the bundle passing through the drive rolls 2.

The tension control unit 3 is made in the form of three rolls 7, 8, 9, connected with a strain gauge 10, located behind the feed rolls 2 and is designed to control the tension of the carbon tow.

The air stream expansion unit 4 of the carbon tow contains a support rolls 11, 12 and a nozzle 13, which is made with a flat slot hole 14 located across the feed direction of the carbon tow and through which compressed air is supplied under pressure. The nozzle is fixed between the support rolls 11, 12 above the carbon tow (and, accordingly, above the support rolls) and with an inclination at an angle α from 30 ° to 70 ° to the supply plane of the tow with the ability to adjust the specified angle depending on the type of carbon fiber and the required width obtained at the outlet of the carbon tape. In the flat slit hole 14 of the nozzle 13, partitions 15 can be formed to separate the air flow with the possibility of the formation of several jets of air.

Behind the knot 4 for expanding the carbon bundle, receiving rollers 5 are arranged, by means of which the controlled carbon tension is moved with adjustable tension. In design, the take-up rolls 5 are similar to the feed rolls 2, while the drives of the feed rolls 2 and the receive rolls 5 are synchronized.

The winding unit 6 of the expanded carbon tow includes a shaft that can be mounted along its axis (0'-0 ') with an adjustable speed, on which both a take-up reel for cross winding with an adjustable folding angle and a coil can be installed.

The installation for straightening the carbon bundle has a programmable control unit by which the basic parameters of the nodes are set, the rotation speeds of the drive units are monitored and synchronized, and the unit automatically stops when the bundle ends in any section, when the bundle ends and when the full shaft is wound.

Installation for straightening the carbon tow is as follows.

The carbon wire bobbin is mounted on the bobbin holder of the winding unit 1. At the same stage, passing the end of the bundle through all the units of the installation (through feed rolls 2, node 3 for controlling and regulating the tension of the carbon bundle, node 4 for expanding the carbon bundle by air flow, receiving rolls 5), fix it on the take-up reel (or coil on the transition sleeve) mounted on the shaft of the winding unit 6.

By means of the control unit, the basic parameters of these nodes are set and the installation for straightening the carbon tow is included.

The carbon bundle, captured by the feed rolls 2, from the winding unit 1, rounding the rolls 7, 8 and 9 of the tension control unit 3, moves through the expansion unit 4 by the air flow, where it is supported by the rollers 11 and 12. At the same time, it is forced through the slot 14 of the nozzle 13 compressed air is supplied. Formed by a flat slotted hole 14, a uniformly wide high-velocity air stream acts on the carbon tow at an angle α to the supply plane of the tow, selected from 30 ° to 70 °, forming a loop, straightens the carbon tow, and pressing it to the support roll 12, distributes into individual monofilaments, which are dispersed over the width of the roll 12. At angles less than 30 ° and more than 70 °, the resulting loop is destabilized, the tension of the carbon bundle increases and, as a result, the efficiency of the strands decreases eniya carbon tow, wherein the carbon ribbon turns of smaller width and greater basis weight. With a large thickness of the bundle, it is preferable to make a slit hole with partitions 15 in order to divide the air flow into several streams for a more even distribution of the strands of the bundle along the width of the roll.

The obtained expanded carbon bundle in the form of a tape is wound with tension on a bobbin or coil of the winding device 6. Winding the tape onto the bobbin is carried out by moving the bobbin to the right and left, and the position of the thread guide does not change, i.e. fixed, while the layout of the tape on the reel is carried out without bends and additions. The winding tension is automatically adjusted. On the panel of the system for controlling and regulating the tension of the processed bundle, the current number of windings in meters and the amount remaining until the bobbin is filled are displayed. After the bobbin is fully wound (after reaching the specified bobbin diameter), the installation automatically stops.

The proposed installation of the expansion of the carbon bundle through the use of a nozzle with a flat slotted hole through which compressed air is supplied and achieving higher air flow rates makes it possible to evenly distribute monofilaments of the carbon bundle and form a uniform ribbon with a low surface density.

Claims (3)

1. Installation for straightening a carbon tow, comprising sequentially located winding unit, a pair of feed rolls, a control unit for controlling the tension of the processed tow, a straightening unit of the carbon tow by air flow, a pair of receiving rolls, and a winding unit of the straightened tow, while the carbon tow straightening unit the air flow is made in the form of two support rolls and a nozzle, which is fixed between the support rolls and above them with an inclination at an angle from 30 ° to 70 ° to the plane is moved a bundle and is made with a flat slot hole with the possibility of supplying compressed air through it under pressure. 2. The installation according to claim 1, in which the slotted hole of the nozzle is made with partitions. 3. The installation according to claim 1, in which the nozzle is mounted with the possibility of adjusting the angle of inclination.

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