DE2540148A1 - High speed coiling of synthetic fibre tow into can - using rotating pneumatic gun whose outlet is inclined to absorb energy (BR210976) - Google Patents

Abstract

A device for coiling a tow of synthetic fibres into a can comprises a pneumatic gun rotating about a vertical axis above the can. The gun consists of a curved tube in which an air nozzle is located and through which the two passes. The tangent to the outlet of the tube is included to the radius of the circle of rotation at an angle of 30-80 degrees. The shape of the outlet of the gun reduces the kinetic energy of the tow, allowing the tow to be feed through the gun in excess of 1000m/min. without tightly packing the two in the can.

Description

Man-made fiber cable conveyor The invention relates to on a conveyor device for man-made fiber cables according to the generic term of the first Claim and a working method for depositing fiber cables in spinning cans according to the generic term of claim fifteen.

Devices of the type mentioned have the purpose of producing multifilament strands from synthetic materials with a higher titre (man-made fiber cables) and to a sliver can in which the tows are deposited1.

In US Pat. Nos. 2,971,683 and 3,706,407 devices are discussed standing genus shown. The rotating guide tube of these devices is simply curved and in its exit area - in projection onto its plane of rotation seen - directed radially.

The disadvantage of this design is that the speed of the fiber cable at the exit of the guide tube - based on a through the axis of rotation placed spatially fixed coordinate system - compared to the feed speed to the Guide tube is increased so that kinetic energy is still supplied to the fiber cable instead of belittling it. This makes sense when one imagines that to the radially directed speed of the fiber cable is the circumferential speed of the rotating guide tube can be added vectorially at the exit point must, and the resulting speed at this arrangement is always greater than the feed speed. The consequence of the increase in speed is that the fiber cable so far after leaving the rotating guide tube is carried outwards until the forces acting on the exiting fiber cable (Air resistance between the fiber cable and the still ambient air) and the The tensile force caused by the rotation of the free fiber-optic screw is sufficient, around the fiber cable at the exit from the guide tube opposite to the direction of rotation of the guide tube to deflect in an arc. This can be especially true at high speeds of the fiber tow lead to the fact that the layering of the yarn in the spinning can is not is satisfactory because, on the one hand, the fiber cable can easily slip over the edge of the can get out and on the other hand results in the rotary movement required in this arrangement the free fiber cable screw in the area between the guide tube and the spinning can, that this only runs out on the already deposited turns of the fiber cable, what can lead to entanglements, which severely impair the subsequent removal of the fiber cable. The rotational movement of the fiber optic cable screw around the axis of rotation is necessary in order for the the deflection at the exit of the radially directed tube by the required tensile force Generate centrifugal forces.

To explain what occurs in a device of the type mentioned Rotational movement is pointed out to the following: The vertical falling movement of a viewed A rotary movement is superimposed on the thread element. The resulting trajectory of the The thread element is a helix. This is to be distinguished from that in a Snapshot for the viewer visible fiber cable screw, which as a power tube can be understood, which is attached to the outlet of the guide tube and with this rotates around the axis of rotation of the device, and through which each thread element flows through.

Turntables from DT-PS 1 115 622 and DT-AS 1 510 310 are also provided named whose guide tubes for the fiber cable to be laid down tangentially u their circles of rotation flow out. There is a very high risk of clogging here, because in the area of the outlet opening one that opens tangentially Guide tube on a fiber cable element attacking resulting acceleration is directed perpendicular to the guide channel and thus only obstructive frictional forces arise in the conveying direction itself, which lead to blockage of the guide tube.

Such a turntable can only work because of the The turntable presses the fiber cable onto the layers that have already been placed in the jug (cf. e.g. DT - PS 1 019 222) and thereby a tensile force on the one from the guide tube the rotating turntable exiting fiber cable is exercised. These well-known Devices are used to deposit card or drawstring slivers in fiber yarn spinning preparation machines used at much lower working speeds.

The object of the invention is to eliminate the known devices inherent disadvantages and the improvement of the laying process for fiber cables, especially at high fiber cable delivery speeds such that the cable almost the full kinetic energy from the high translational delivery speed is withdrawn and the cable forming a stable helical configuration is conveyed between the rotating storage element and the spinning can. It must be achieved that the fiber cable in the guide channel of the storage organ always through the acting inertial forces is promoted and that such transverse forces are avoided in cooperation with the friction of the fiber cable on the wall of the guide channel lead to clogging of the guide channel.

The solution to this problem for a device in the preamble of claim 1 specified genus results from the characteristic of the first Claim.

The advantage of the solution shown is over the per se known turntables in that the cable exiting the rotating guide tube sufficiently high hatred forces in the direction of the guide tube is exposed to a Blockage of the guide tube impede. Furthermore, the formed according to the invention guide tube has a stable helical configuration of the fiber optic cable. The kinetic energy of the succeeds with the guide tube at high speeds of over 1,000 m / min - even over 3,500 m / min - to remove almost completely the cable brought up to the guide tube and that Place cables in the spinning can without being compressed, damaged or entangled. Thanks to the device, it is possible to do this from spin-draw or draw-spinning processes delivered fiber cables in perfect layering in the rotational una / or jug that changes translationally and even at high speeds to withdraw from it again without difficulty.

In this embodiment of the invention, it should also be ensured that the conveying forces acting on the fiber cable are suitable in terms of direction and size are also to overcome the friction of the fiber cable on the guide tube wall.

This is done according to the invention in that the radius of curvature of the guide tube in the exit area in coordination with the exit angle The mathematical relationships specified in the characterizing part of claims 2 and 3 are sufficient, wherein in particular the relationship according to claim 2 is critical.

The construction of the device according to claim 4 ensures that the helical configuration of the fiber cable behind the guide tube Has sufficient pitch and speed of fall. The exit speed of the fiber cable receives a component acting in the direction of gravity.

The device according to the invention or its developments are obtained advantageously devices that are capable of reducing the air resistance of the helical configured fiber cable in the vertical movement direction to compensate. The proposals according to claims 5 and 6 are used for this purpose.

In claim 7 is a preferred embodiment of the invention Device specified for high feed speeds of the fiber cable and thus it is particularly well suited for high speeds of the filing member, since this is the case an aerodynamically favorable shape of the rotor was chosen and the rotor was made lighter and can be balanced.

The proposal according to claim 8 also has the particular advantage that the downwardly sloping helical configuration of the fiber cable does not uncontrolled air currents that are parallel to the axis of rotation of the guide tube within the helical configuration of the fiber cable. the proposed design of the rotating body and the specified assignment of the annular Air nozzles cause the helical configuration of the fiber optic cable into a downward airflow is placed.

For such a rotor it is proposed according to patent claim 9, above the outlet opening of the guide tube, preferably several inwards provide directional channels that are in a downward direction and coaxial with the axis of rotation provided channel open, which exits on the underside of the rotor. Through this becomes a negative pressure area below the rotor, which constricts the annular gap flow the downward-directed conveying air supplied by the air nozzle, filled up and the fiber cable screw advantageously stabilized.

The further developments and refinements of the invention Devices are aimed at the operational safety of the device as possible wide ranges so that it is not absolutely necessary when operating the device on an overly precise coordination of the speed of the guide tube having to adjust the thread speed. Advantageous refinements are in the dependent claims 9 to 14 specified.

According to the preceding statements on the present invention The invention relates to the device with regard to the stated object as a general idea of the invention, a working method according to the characteristics of the Claim 15 is based.

What is essential to the invention is - and in particular the The difference to the prior art is clear - that according to the invention, a filing method for man-made fiber cables is realized based on the principle of a reaction machine (Seeger water wheel, reaction turbine, etc.) is used and in which the large kinetic energy of the translational movement of the fiber cable approximating this is completely withdrawn, transformed into kinetic energy of a rotational movement which helps to drive the guide tube or the rotor. The limitation the moisture of the fiber cable according to claim 16 is essential, than this is the exercise coefficient t between the fiber cable and the guide tube or the deflecting organ is affected and with a relatively dry pulp fiber cable with a moisture content of less than 3%, there is practically no dependence on the coefficient of friction / was determined by the cable speed while this dependency was Moisture values above 12 wt. Must not be neglected.

In the following the invention is based on an exemplary embodiment and the drawings.

They show: FIG. 1: Schematic drawing of the device with guide tube in the plan view of the plane of rotation of the outlet opening, FIG. 2: the device according to Fig. 1 in the view, Fig. 3: Another embodiment with in one Rotary body embedded guide tube.

4: the acceleration vectors occurring in the exit area of the guide tube; 5: a rotating body with an embedded guide tube and air guide channels; FIG. 6: the top view of the rotating body according to FIG. 5.

The projections of the spatially curved guide tube according to the figures 1 and 2 show that the inlet opening of the guide tube 1 into which the from the Conveyor rollers 3 supplied fiber cable 2 enters on the axis of rotation 14 of the guide tube lies. The guide tube 1 is rotatable in the bearings, for example roller bearings 8 stored and by the schematically illustrated drive 9 with the direction of rotation of arrow 16 driven. The speed (n) of the guide tube 1 is chosen so that that its related to the diameter of the helical turns 4 / slightly, d. H. 5% to a maximum of 20 times greater than the delivery speed (Vf) of the fiber cable 2 before entering the guide tube.

The guide tube 1 is spatially curved. The radius of curvature is Not constant over the length of the thread guide tube. At the outlet opening 10 the guide tube 1 has a radius of curvature (), its projection in the horizontal plane of FIG. 1, the variable tfh) and its projection into the vertical plane of FIG. 2 the size (? y) and the on the exit angle (p) of the guide tube is matched. is the spatial angle with which the tangent to the guide tube 1 at the outlet opening 10 from the radial direction pointing towards the axis of rotation 14 deviates. The one that changes over the length of the spatially curved guide tube Radius of curvature 9 is chosen so that at each point of the guide tube a resulting Inertial force acts whose component in the conveying direction is greater than the frictional force, so that clogging of the thread guide channel is prevented.

*) Peripheral speed The training of the spatial However, curvature has been found to be largely uncritical, provided that the Radius of curvature, ° of the guide tube 1 in the area of the outlet opening 10 is the mathematical Condition r <# <r 2 - sinfl + cosA 2 - sinA is met; r is in this Formula of the radius of the turning circle 17 of the outlet opening 10; µ is the coefficient of friction of the sliding fiber cable opposite the guide tube 1.

According to this invention, the angle β is less than 90 ° and is preferred between 30C and 800. This and the coordination of the radius of curvature P des Guide tube 1 in the area of the outlet opening 10 is achieved that the fiber cable 2 is positively promoted by the acting inertial forces and when leaving of the guide tube 6 1 also has a speed component relative to the turning circle 17 of the guide tube 1 has.

The direction and magnitude of the tensile forces acting on the fiber cable are sufficient for the specified dimensioning of / and # to compensate for the by the shear forces induced friction of the fiber cable on the tube wall of the guide tube 1 to overcome. The most favorable angle ß must be optimized through experiments within the specified limits and selected so that the radius of curvature in view of the other operating conditions has a technically feasible size.

The following are the mathematical relationships between the angle ß and the radius of curvature £ at the exit point 10, taking into account the thread friction derived, referring to the vector diagram of the accelerations occurring Fig. 4 is referenced.

1. The condition for ideal delivery conditions in the exit area is, that for a single thread element the resulting acceleration babs (ideal) has the same direction as the tangent to the guide tube 1 at the outlet opening 10, so no acceleration component and therefore a force component normal to the guide tube is present, 80 that no frictional force acts on the thread element. For this ideal case the following applies to a good approximation for small angles α: | bc | - | br | = sing ß; | bz | where: bc = 2. #. vf (Coriolis acceleration, lies in the plane of the drawing), vf² br = = # ². # (relative acceleration, # (is spatial), bz = # ². r (centripetal acceleration, lies in the plane of the drawing).

With the special operating condition #. r = vf, can be written become: 2 2 b = 2. Vf b = v c z r r where # = angular velocity, r = radius, on which the guide tube 1 ends, Vf = delivery speed of the fiber cable; used: 2vf² - vf² sin ß = r # = 2 - r and 2 Vf r r 2 - sin ß 2nd condition for a positive Promotion of the fiber cable in the exit area of the guide tube while overcoming it the wall friction (b abs. real) is that # #> arc. tan µ tan #> µ; wherein: µ ..... coefficient of friction between fiber optic cable and pipe; # ..... angle of friction, at self-locking occurs in the thread guide tube; from Fig. 4 follows: - z '| bc | - | br | = | bz | . sin ß tan # tal 2 #. vf - = # -. r (sinµ -); # tan # with the special operating condition Vf #. r = vf; # = can be written: r cosß vf² vf² vf² 2 - = (sinß-); r # r tan # cos ß sin ß -tan # 1 / # = 2 / r -; # =; 2-sin ß + cos ß tan # or with tan #> µ. r #> 2 - sin ß + ####.

With this design of the radius of curvature # of the guide tube 1 Self-locking avoided.

For the determination of # the following condition applies: r r 2 - sin ß 2 - sin ß + #### where the right-hand side of this mathematical relationship is mandatory must be and represents a critical limit.

In practice, g is about 50-90% of r, with the larger values of 9 when filing a damp fiber cable come into consideration and for large ones Exit angle ß apply.

With this embodiment of the device, the fiber cable 2 after leaving the outlet opening 10 a downwardly moving helical shape Configuration 4 to lend. To this helical configuration such a To give pitch (h) that the individual turns do not touch each other and not hindering each other even with small, unavoidable air movements, is one Minimum aisle height determined, which depends on the operating conditions and should not be less than 10 to 20 mm depending on the titer and number of multifilaments. Of the Winkelo under which the outlet opening 10 - as can be seen from Figure 2 - against the plane of rotation of the outlet opening is inclined downwards, then results from the mathematical relationship h tan OC = R The angle OC is according to this invention between 50 and 30 and preferably remains less than 1) 0. The pitch should be also for this reason not be too small, so that the individual helical turns, which forms the fiber cable under the guide tube, no too little translational Gt 'speed component towards the jug have what the overall configuration of the fiber cable is susceptible to undesired, from it inevitable air currents would do.

The radius (R) of the helical turns that make up the fiber optic cable forms when exiting the guide tube, depends once on the angles (OC) and ()) as well as from the radius (r) of the turning circle 17 of the outlet opening 10 of the Guide tube 1.

In addition, the fiber cable speed is also an operating parameter (v) as well as the speed (n). To be precise Vote this To make operating parameters superfluous, the device can - as to figure later 3 described - be surrounded with a cage.

It should also be noted that during operation the speed (n) of the thread guide tube 1 is preferably chosen so that its on the diameter the formed thread screw 4 related peripheral speed about 5% to 20% greater than the feed speed of the fiber tow (v) when entering the depositing device is. As a result, adjustable centrifugal forces act on the fiber cable, which put the fiber cable under tension and the thread screw 4 a sufficient give spatial stability.

It should also be mentioned that the rotating guide tube a known injector nozzle can be connected upstream in order to start the Device for the transfer of the fiber cable delivered at high speed vF to enable the guide tube 1. This injector can also do this during operation be used that with high existing coefficients of friction +, as in an extremely moist fiber cable with a high content of finishing agent, for example 10% can be observed1 the conveyance of the fiber cable 2 in the guide tube through the Air flow is supported.

It is clear that the falling to the spinning can 7 in still air Windings 4 of the fiber cable are exposed to air resistance. About this air resistance to partially compensate and a reduction in the pitch h between the turns To prevent below a permissible level, an annular gap nozzle 5 is concentric to the Turning circle of the outlet opening 10 and provided approximately at its height. through this Nozzle creates a downward flow of air in which the helical Coils 4 of the fiber cable lie and are promoted downwards.

The embodiment shown in Fig. 3 also includes the 1 and 2 illustrated principles of the device according to the invention. The guide tube 1 is arranged in a rotating body 18. The rotating body 18 is again stored in bearings 8 and is driven in the direction of arrow 16. Of the The radius of the rotating body 18 increases - seen from top to bottom - initially and then off again. In the case shown, the rotating body consists of two straight lines Truncated cones that are set against each other with their base circles.

The outlet opening 10 is located in the area of the rotating body with a decreasing cross-section downwards. The annular nozzle 5 rests on the upper part of the rotating body, so that the exiting air curtain 11 first has a widening radius, but then with a decreasing diameter of the rotating body and thereby also a component of movement due to the rotation of the rotor in the circumferential direction. As a result, the in connection with Fig. 1 and Fig. 2 described promoting effect of the air flow for the helical configuration the fiber cable brought about.

By designing the rotor 18 in the lower part as a displacement body is also avoided1 from a fluidic point of view under the rotor "Dead water area" trains. Another advantage of the design of the Rotor 18 with the embedded guide tube 1 lies in the improved aerodynamic Properties of the device, in the increased rigidity of the device, the better balancing and easier accident protection.

The embodiment according to FIG. 3 has a cage 6. The cage 6 can be designed as a closed tube. In the embodiment there is however, it consists of individual rods 15 arranged parallel to the axis of rotation 14.

The radius of the circle on which these rods 15 are concentric to the rotating body 18 can be adjusted.

Furthermore, the bars can be inclined so that the cage a has a frustoconical widening cross-section downwards. The cage begins approximately at the level of the circle of rotation of the outlet opening 10 and can extend up to the upper Edge of the spinning can 7 extend.

It preferably extends over two to ten times the pitch (h) the helical configuration 4 of the fiber cable 2 below the exit opening 10 and serves to limit the radius (R) of this helical configuration.

If the cage 6, which essentially serves the purpose, when starting up of the device to limit the diameter of the fiber cable screw being formed, as a closed cylindrical or frustoconical expanding hollow body that limits the flow of downward air, it is very advantageous to make this double-walled and with sound-absorbing building materials to isolate. The inner wall of the hollow body is made in a manner known per se formed from finely perforated sheet metal.

It should be mentioned that the can 7, in which the turns of the fiber cable stored turn, translationally (arrows 13) and / or rotatory traversed. This ensures that the fiber cable 2 over the horizontal cross-section the jug is deposited evenly and without difficulty can be withdrawn from the jug again. At 12, the amount is in the jug denotes fiber cable 2 deposited in turns 4.

4 shows the accelerations acting on the fiber cable element and their vectorial addition, where for small angles of inclination oc is the solution the level of characters shown is an approximate solution.

5 and 6, a similar rotating body 18 is embedded with Guide tube shown as in Fig. 3. The rotating body in Fig. 5 is in two parts and consists of the feed section 19 for the fiber cable and the one below it Displacement body 20. To counteract a negative pressure area below the rotor, there are three inwardly directed channels on the conical surface of the feed section 21, 22, 23 arranged, which are provided in a coaxial with the axis of rotation 14 and themselves The channel 24, which widens towards the outlet of the displacement body, opens. Through these channels air is blown through the rotor by a fan not shown in detail. The arrows, which are not designated in more detail, in FIG. 5 indicate the direction of flow of the air at.

Claims (16)

Claims conveyor for feeding one at lower speeds of more than 1G00 mZmin, freshly spun essentially delivered in a straight line and / or stretched man-made fiber cable to a storage can in helical Windings, consisting of a rotatably mounted with respect to a vertical axis and about this axis drivable, curved guide tube with a close to or coaxial the inlet opening lying to the axis of rotation and one at a radial and an axial distance from the inlet opening arranged outlet opening, the tangent to the guide tube in the area of the outlet opening is inclined to the normal to the axis of rotation, one curved thread guide channel between the inlet and outlet openings and a nozzle conveyor in the thread guide channel, characterized in that the guide tube (1) in itself As is known, spatially curved between the inlet opening and the outlet opening (10) is, and that the tangent to the guide tube in the area of the outlet opening (10) with the radius of its turning circle (17) an angle of inclination β between 30 and 800 includes. 2. Apparatus according to claim 1, characterized in that the radius of curvature () of the guide tube (1) in the area of the outlet opening (10) of the mathematical The relation r #> cos ß 2 - sin ß + µ is sufficient, where r is the radius the turning circle of the outlet opening, the angle that the tangent to the guide tube encloses in the area of the outlet opening with the radius of its turning circle, and »Is the coefficient of friction between the fiber cable and the guide tube. 3. Apparatus according to claim 1, characterized in that the radius of curvature (8) of the guide tube (1) in the area of the outlet opening (10) the mathematical Relationship r 2 - sin # fulfilled. 4. Device according to one or more of the preceding claims 1 to 3, characterized in that the outlet opening (10) to the plane of its turning circle has an angle of inclination OC between 5 and 30 downwards. 5. Device according to one or more of the preceding claims 1 to 4, characterized in that above and concentrically to the turning circle (17) the outlet opening (10) an annular gap nozzle (5) with essentially vertical after is arranged downwardly directed nozzle lips. 6. Apparatus according to claim 5, characterized in that the annular gap nozzle (5) facilities are assigned to the exiting Airflow in addition to the essentially vertical flow direction, a component in the circumferential direction To give. 7. Device according to one or more of the preceding claims 1 to 6, characterized in that the guide tube (1) in a rotation axis around the (14) embedded rotatably mounted and drivable about this axis rotating body (18) is, wherein the outlet opening (10) of the guide tube on the circumference of the rotating body (18) opens, and that concentrically to the rotating body (18) an annular gap nozzle (5) so arranged with essentially vertically downwardly directed nozzle lips is that the nozzle (5) is free of contact above the outlet opening (10) of the guide tube rests on the rotating body (18). 8. Apparatus according to claim 7, characterized in that the rotating body (18) has a frustoconical section (19) pointing towards the delivery mechanism (3), possibly connected to a circular cylindrical section viewed in the conveying direction is, and that the sliver can (7) facing section (2C) as a displacement body formed and to the air flow formed during operation of the device is adapted. 9. Device according to claims 7 and 8, characterized in that that in the frustoconical feed section pointing towards the delivery mechanism (3) (19) of the rotating body on the cone shell beginning channels (21, 22, 23) are provided are, which in the interior of the rotating body in a coaxial to the axis of rotation (14) and channel (24) which preferably widens towards the outlet in the displacement body (20) flow out. 10. Device according to one or more of the preceding claims 1 to 9, characterized in that concentric to the turning circle (17) of the outlet opening (10) of the guide tube (1) is cylindrical or frustoconical downwards expanding hollow body is arranged. 11. The device according to claim 10, characterized in that the Hollow body as the rotating body (18) enclosing and extending beyond this, downwardly open soundproof pot is formed. 12. The device according to claim 10, characterized in that the Hollow body as a cage (6) consisting of rods (15) with a circular horizontal cross-section is trained. 13. Apparatus according to claim 10 and 12, characterized in that the rods (15) in a fixed mounting plate on different Cage diameter are arranged adjustable. 14. Apparatus according to claim 10 to 13, characterized in that distributed at axial intervals over the longitudinal extent of the cage (6) or hollow body Annular gap nozzles (5) directed obliquely inwards and downwards are arranged. 15. Working method for feeding one at delivery speeds from more than 1000 m / min in a straight line vertically downwards delivered, freshly spun or stretched man-made fiber cable to a spinning can in helical turns, in which the man-made fiber cable is laid down from its direction of movement and by overlaying ' a rotational movement is brought on a helical path, thereby characterized in that the deflection of the man-made fiber cable (2) on the helical Trajectory (4) follows on a space curve in such a way that during the deflection the kinetic energy of the translational movement approximates the man-made fiber cable (2) is withdrawn and transferred to the deflection device, and that at each point of the three-dimensional curve is the one that acts on each element of the man-made fiber cable Inertial force in the direction of the space curve exceeds the restraining frictional force. 16. learn to claim 15, characterized in that the moisture of the man-made fiber cable (2) as a result of previous finishing or the like The value is set to be less than 12% (% by weight), preferably less than 5% (% by weight) will.