FR2670694A1 - MULTIFILAR DRAWING DEVICE AND WICK OBTAINED USING THE SAME. - Google Patents

Abstract

Multi-wire drawing device, for the manufacture of a wick of metal wires, comprising a line for drawing by wire of said wick, means for regulating the drawing speed and the traction of said wires, then coupling means for each of said wires drawn separately, in order to form said wick, and finally, means for uniformly distributing said wick on a main winder, characterized in that each of the drawing lines consists of a single-wire drawing machine (A, A ' , A ", B) comprising a drawing block (3A, 3A ', 3A", 3B), means (5A, 5A', 5A ", 5B), specific to this machine, for regulating the drawing speed and of the traction of the drawn wire by this machine and a winder (1A, 1A ', 1A ", 1B), only one of the single-wire machines, called receiving machine (B), being intended to receive on its winder (1B), called winder main, the wick (12), the winders (1A, 1A ', 1A ") of the other single-wire machines s (A, A ', A "), called debtor machines, not being used, and single-wire machines (A, A', A", B) each further comprising a coupling means (7A, 7A ' , 7A ", 7B) of each of the wires (10A, 10A ', 10A", 10B) drawn separately at speed and traction regulated to the other wires in order to constitute the wick (12) winding itself as and uniformly on the main winder (1B).

Description

Multi-wire drawing device and bit obtained using this

  device The subject of the present invention is a multi-wire drawing device, for producing wicks of metal wires intended in particular for the manufacture of braids, strands, or twists. Current multi-wire drawing machines (or multi-wire machines) can draw up to 24 wires in parallel. Some of these machines include a drawing block made up of several drawing lines (depending on the number of wires to be drawn). Each line contains a series of dies interspersed with stepped cones secured to a common shaft Each wire follows a drawing line and passes from one die to another by means of a stepped cone Its section decreases progressively by passage from one die15 to the other All the threads constituting a wick are then directed to a regulating jig and then to a winding machine by means of a deflection pulley The puppet makes it possible to regulate the drawing speed and to adjust the traction of the wick; such multi-wire machines can draw up to ten wires in parallel. Other multi-wire machines different from those which have just been described comprise ribbed drawing capstans instead of cones with

  bleachers This allows several wires to be drawn on the same line, the wires being side by side on the capstans and passing through multiple dies. This type of multi-wire machine allows to draw up to 24 wires at a time The final diameter of the wires obtained thanks for multi-wire machines is between 0.05 and 0.5 mm.

  These machines have many drawbacks. First of all, their yield is lower than that obtained with single-wire machines. In the range of diameters between 0.05 and 0.20 mm (fine wires), the maximum yield obtained in multi-wire is of the order of %; for diameters between 0.20 and 0.50 mm (thick wires), still in multi-wire, it is at most 65% The single-wire machines have them, an efficiency of about 80% This is due to 35 problems related to the breakage of the wires Indeed, during the breakage of a -2- wire in monofilar, the re-threading is carried out easily and quickly (in about a quarter of an hour) On the other hand, the breakage of a wire in multifilaire obliges to stop wire drawing for at least an hour, and moreover, re-threading is very laborious and difficult. This explains the low yield obtained in multi-wire, in particular for fine wires which break more easily. In addition, in the case of ribbed capstan machines, the breakage of one wire can cause breakage of other wires, which further reduces performance. In addition, the speeds are limited in multi-wire; in practice, the maximum speed is of the order of 30 ms, and 15 ms in particular for fine wires when we reach 35 to 50 ms-1 in

  monofilaire This is also due to the breakage of the threads The higher the speed, the more there are risks of breakages This problem is accentuated in multifilaire where the breakage of a thread can, as we saw above, lead to the break other sons.

  Another major drawback of multi-wire machines comes from the loosening of the wires. In fact, a single regulating puppet (called grouped puppet) regulates the speed of the drawing and the traction of the wick of wires. It can therefore happen that one or more wires are

  release in the wick; this non-homogeneity of the traction prevents the proper functioning of the winding.

  On the other hand, in a multi-wire machine provided with a continuous annealer, the wires being grouped to be dried and therefore very close to each other, the air jet used for example, is not sufficient to evaporate the between two wires This causes water retention at the level of the wick, and therefore a

oxidation of the wires.

  Finally, multi-wire machines are not very flexible They are designed to draw a given number of wires with the possibility of reducing this number in a very limited interval (in practice, the composition of the wick can be reduced by a maximum of 3 to 4 wires)

  Therefore, even if it is possible to vary the composition of the wick, it is better not to reduce the number of yarns produced too much, as this still leads to a reduction in yield. In particular, these machines never produce a yarn to the time.

  -3- The object of the present invention is therefore to produce a multi-wire machine having a yield and a speed close to that of single-wire machines. In addition, it aims to overcome the problems of non-homogeneity of traction and oxidation of the wires. encountered with multi-wire machines Finally, it offers a flexible solution usable either in single-wire or in multi-wire

  with composition of variable wicks, without drop in yield.

  The present invention provides for this purpose a multi-wire drawing device, for the manufacture of a wick of metal wires, comprising a wire drawing line per wire of said wick, means for regulating the drawing speed and the traction of said wires. , then means for coupling each of said drawn wires separately, in order to form said wick, and finally, means for uniformly distributing said wick on a main winder, characterized in that each of said drawing lines consists of a machine wire drawing machine comprising a wire drawing block, means, specific to said machine, for regulating the wire drawing speed and the traction of the wire drawn by said machine and a winder, only one of said single wire machines, called receiving machine, being intended to receive on its winder, said main winder, said wick, said winders of other monofila machines ires, said debit machines, not being used, and said single-wire machines each further comprising a means of coupling each of said drawn wires 25 separately at regulated speed and traction to the other wires in order to constitute said wick being wound up as and uniformly on said main winder. According to a possible operating mode, the monofilament machines are placed one after the other, the first being one of the debtor machines and the last the receiving machine; the first wire drawn separately and coming from the first machine is sent, thanks to the coupling means of the first, on the coupling means of the second machine, this coupling means therefore recovering the first wire and the second drawn wire separately35 coming from the second machine, and so on until the means -4- of coupling of the receiving machine, which recovers the grouped wires from the debtor machines and the last wire drawn separately coming from the receiving machine, the wires thus grouped constituting the wick. 5 According to an important characteristic, the coupling means of each single-wire machine are orientable, so that each of these machines can be integrated into another multi-wire line, the wire of this machine being directed to another Multi-wire drawing line. 10 On the other hand, the means of regulating the drawing speed and the traction of each of the single-wire machines can be control jacks We will preferably take light control jacks for the range of diameters between 0.05 and 0.20 mm, and heavy control jacks for the range

0.20-0.50 mm.

  The main winder can be a dynamic winder In this case, the means used to distribute the wick evenly over the main winder is a cutting pulley whose cutting pitch is adapted to the width of the wick in order to constitute a uniform winding. main winder is a static winder, the cutting is ensured by the winder itself, provided with a motor allowing it to carry out a translational movement parallel to its axis, at a speed adapted to the width of the wick in order to constitute a uniform winding. 25 According to another characteristic, the means for coupling the wires are external return pulleys each secured to one of the single-wire machines. These pulleys can be orientable and can rotate around a vertical axis tangent to their bottom. throat. In addition, these pulleys can be provided, at the input and output, for example, with a system for holding the wire (s). This holding system can be a pinching system with felts, a system with eyelets or a system with support by shell surrounding the pulley and having openings allowing the son or wires to pass. Finally, each monofilament machine may further include a continuous annealing device located between its drawing block and its means of regulation. Using a device according to the invention, wicks of oxidation-free wires can be produced. These wicks can be used: to make strands or twists usable in the manufacture of flexible conductive cords, insulated or not;

  to make braids that can be used for shielding in cables.

  Characteristics and advantages of the present invention will appear during the following description of a mode of implementation

  work of the device according to the invention, given by way of illustration and in no way limitative.

In this description

  FIG. 1 illustrates a single-wire machine used in a device according to the invention, FIG. 2 represents the operating diagram of a device according to the invention, FIG. 3 shows a side view of a control valve used in the device according to the invention, FIG. 4 diagrammatically represents by blocks the chain of

  regulation of the traction of the wire and the drawing speed of a single-wire machine used in the device according to the invention.

  FIG. 5 illustrates an external deflection pulley of the device presented in FIG. 1, FIG. 6 illustrates in section a system for holding the wire (s) on the deflection pulley illustrated in FIG. 5, FIG. 7 illustrates in perspective another system for holding the wire (s) as that of FIG. 6, FIG. 8 illustrates in perspective an orientable external deflection pulley, and provided with a system for holding the wire (s) still different from those illustrated in FIGS. 6 and 7, Figure 9 illustrates in section a variant of the pulley shown

in Figure 8.

  In Figure 1, there is shown in front view a single-wire machine used in a device according to the invention This single-wire machine comprises a drawing block 1, an annealing device 2 and -6 - a winder 3 called dynamic winder, it is that is to say that the winder 3 is provided with a motor (not shown) communicating to it a movement of

  proper rotation around its longitudinal axis.

  The drawing block 1 consists of 4 stepped cones 4, 2 dies 5 and a pulley 6 A wire 7 following the path shown in solid line in the figure can pass up to 20 times in the dies 5, according to the desired final diameter Then, the wire 7 is directed into the annealer 2 by means of a pulley 8 Finally, at the outlet of the annealer 2, a drawing capstan 9 brings the wire 7 to a regulating jig 10 which makes it possible to regulate the traction of the wire 7 and control the speed of the wire drawing to that of the winder 3 The wire 7 is

  then directed by a return pulley 11 on a pulley 12.

  This pulley 12 is driven in a translational movement parallel to its axis called "cutting movement", which is communicated to it by a motor 13, and which is intended to uniformly distribute the wire 7 on

the entire length of the winder 3.

  The drawing block 1 as well as the dynamic winder 3 are driven by DC motors with variable speed drives

with thyristors (not shown).

  In FIG. 2, four single-wire machines A, A ', A "and B of the type described in FIG. 1 have been coupled. On machines A, A' and A", the winders 1 A, l A 'and l A "and the cutting pulleys 2 A, 2 A 'and 2 A" have been short-circuited (this is why they are shown in broken lines) Machines A, A' and A "will be called" machines " "Only the winder 1 B and the cutting pulley 2 B of machine B can operate This machine will be called in the following" receiving machine "Each machine A, A ', A" and B has a drawing and annealing block 3 A, 3 A ', 3 A "and 3 B, a draft capstan 4 A, 4 A', 4 A" and 4 B, a control valve 5 A, 5 A ', 5 A "and 5 B, an internal return pulley 6 A, 6 A ', 6 A "and 6 B and an external return pulley with flat groove bottom 7 A, 7 A', 7 A" and 7 B. During operation of the device, four drafts (not shown) are introduced respectively at the entry in indicated by arrows ll A, ll A ', ll A "and ll B of machines A, A', A" and B. -7- Each of the blanks is drawn separately and the wires 10 A, l OA ', l OA "and the OB thus obtained are also annealed and dried separately. Then, each of the wires l OA, l OA ', l OA "and OB is brought by means of the respective capstans 4 A, 4 A', 4 A" and 4 B to the control jacks 5 respective 5 A, 5 A ' , 5 A "and 5 B Each of these jacks makes it possible to regulate the drawing speed and the traction of the wire Then, the wires l OA, OA 'and OA" and OB are directed respectively on the internal return pulleys 6 A, 6 A ', 6 A "and 6 B, then on the external deflection pulleys 7 A, 7 A', 7 A" and 7 B. These external deflection pulleys were fixed on the initial machines A, A ' , A "and B The wire l OA is directed by the pulley 7 A on the pulley 7 A ', which therefore collects both the wire l OA and the wire 1 OA' The wires l OA and l OA 'are directed by the pulley 7 A 'on the pulley 7 A ", which collects the wires l OA, l OA' and l OA" Finally, the wires l OA, l OA 'and 10 A "are directed by the pulley 7 A" on the pulley 7 B which then collects the four wires l OA, l OA ', l OA "and l OB constituting a wick 12 This wick 12 is directed by the pulley 7 B on the cutting pulley 2 B then wound on the winder 1 B The cutting speed communicated by a stepping motor (not shown) is adapted to the width of the drill bit 12 so that that the winding is done uniformly on the winder 1 B.

  Figure 3 shows in detail one of the control puppets mentioned above.

  This regulating puppet is called "light regulating puppet" and is more particularly used in the range of fine wires (diameter comprised between 0.05 and 0.20 mm) It comprises a pulley 20 integral with an arm 21 on which a mass 22 can slide, and a balancing counterweight 23 A potentiometer 24, roughly represented, makes it possible to transmit the tensile stresses30 applied to the puppet to the wire drawing motor, in order to regulate the speed of the wire drawing (we will see in detail the mode of operation of such a puppet in FIG. 4) Before starting the drawing, the mass 22 of each of the puppets of the monofilament machines of the device of FIG. 2 is positioned on the arm 21 and fixed in an identical position for all the masses This position determines -8-

a given pull of the wire.

  Each puppet works in traction and speed regulation, which prevents the loosening of one of the wires, since all

  the puppets are slaved to the same reference traction determined5 by the initial position of the mass 22.

  When the traction on the wire increases, for example because of an increase in speed linked to a rise in speed or to a variation of diameter on the reel, the pulley of the puppet rises upwards in figure 2 Then, the position angle of the arm of the puppet10 changes The potentiometer 30 (see figure 4) linked to the puppet transmits this variation of angular position to a regulator 31 of the type

  proportional-integral, which, after integration transforms this data into a voltage U proportional to a speed The voltage U is then compared by the comparator C to a voltage UT proportion-

  at the speed VT of the motor of the wire drawing machine 32 (a dynamo-speedometer 33 allows the transformation of the speed VT into

  a signal equivalent to a voltage: UT) At the output of comparator C, the non-zero difference ú between U and UT controls, if it is greater than a threshold value úo, a speed variator 34 which allows the drawing speed to be increased VT up to a value such that the pull on the wire returns to its set value.

  The reasoning is identical when the traction on the wire decreases.

  In FIG. 5 is shown the external deflection pulley 7 A "of the device described in FIG. 2; the other external deflection pulleys are similar to this The pulley 40 with flat groove bottom intended to receive several wires side by side side is mounted on a plate 41 secured to a frame 42 fixed to the single-wire machine A "The wires 1 OA and 1 OA 'coming from the previous single-wire machines A and 30 A' of the device according to the invention arrive in the direction of the arrow 43 The wire 1 OA "coming from machine A" comes to join the previous ones Before arriving on the pulley 40, it passes through a braking system by felt pads 44 preventing it from deviating from its trajectory and holding it firmly to prevent any loosening The wick thus formed of the wires 1 OA, 1 OA 'and 1 OA ", coming from the pulley 7 A" passes 9 -

  also by another felt braking system 45.

  Figure 6 shows in detail and in section along line VI-VI of Figure 5 the braking system by felts 45 for example of Figure 5 It consists of two identical felts 51 and 52 The felt 51 is directly fixed (by gluing for example) to the plate 41, and the felt 52 is pinched against the felt 51 by a felt-tip pliers 53 Thus, the wires l OA, 10 ′ and 1 OA "passing between the felts 51 and 52 are clamped firmly so to avoid a possible deviation of

their trajectory.

  FIG. 7 shows in perspective another system for holding the wire equivalent to the pinching system by felts of FIG. 6.

  Here, two eyelets 61 and 62 are placed respectively at the input and at the output of the pulley 40 of FIG. 5 Thus, the wire 1 OA "can only move laterally within a given interval.

  In FIG. 8, the pulley 71 is surrounded by a cylindrical torus or "shell" 72 in which an opening 73 is made allowing the exit of the wire 74 This opening maintains the wire in a given interval On the other hand, the shell 72 is provided with a "tail" 75, in the form of a hollow cylinder whose longitudinal axis X 'is vertical and tangent to the bottom of the groove of the pulley 71 This tail is fixed to a support 76 (see FIG. 9) integral with one of the single-wire machines of the device according to the invention The tail 75 has the function on the one hand of holding the wire coming from the single-wire machine to which it is attached, and on the other hand, it can

  rotate around its axis X 'in the direction of arrow 77 or arrow 78, carrying with it the shell 72 and the pulley 71.

  The external deflection pulley thus formed can operate in two modes. In a first operating mode, it is integrated in a wire drawing line according to the invention, and is therefore also intended to possibly receive wires coming from other single-wire machines. therefore another opening 73 '(see FIG. 9) similar to the opening 73 and symmetrical to the latter with respect to the vertical X axis passing through the center of the pulley 71 In a second operating mode excluding the possibility of receiving d 'other wires, this deflection pulley - exterior pivots around the axis X' so that the wire coming from the single-wire machine of which it is integral is directed to another device according to the invention and coupled to the other wires drawn by

  this device as described in FIG. 2.

  It is thus very easy to vary the composition of the

final wick.

  The multifilar device thus produced has a yield of between 70 and 75%, whatever the range of diameters of the wires to be obtained. Indeed, when breaking a wire, re-threading is rapid because it suffices to re-thread a single wire on a single-wire machine It is also possible to hold one (or more) single-wire machine (s) in reserve with their blank already threaded So, when one (or more) wires are broken, it is restarted very quickly the device by replacing the machine (s) whose wire is broken by the machine (s) held in reserve In addition, each wire being separated during the drawing, the breakage of 'a thread does not entail

not the case of others.

  The wire drawing speed reached is around 35 ms-1 for the 0.05 0.20 mm diameter range, whereas multi-wire machines

  of the prior art did not allow to exceed 15 to 2 Oms-1 in practice in this range.

  On the other hand, the pulls of each yarn are homogeneous in the wick thanks to the use of a dummy of regulation by wire This

  prevents the loosening of one or more threads in relation to the others.

  In addition to the great control of the drawing speeds and of the wire pulls brought by the use of regulators like the regulating jacks, the latter allow a very easy threading or re-threading In fact, at the slightest pulling stress of the thread to be threaded, by For example, the puppet reacts immediately30 via its potentiometer which excites the drawing block motor. Threading (or re-threading) is therefore carried out simply and quickly. Advantageously, each wire is annealed and dried separately before being collected by the external deflection pulleys. Thus, the oxidation problem due to the group drying of the -

son is avoided.

  Finally, the device according to the invention is very flexible since it is possible to draw any number of wires by adding or

  removing one or more machines from the wire drawing line This adaptation is moreover very rapid It is also possible to work in a single wire without affecting the performance of the device For this, it suffices to restart the winding of one of the single wire machines and disconnect it from the others by removing the external deflection pulley.

  The device according to the invention thus makes it possible to work in multi-wire while keeping a possibility of use in single-wire In practice, it therefore facilitates the creation of a flexible single-wire / multi-wire workshop which makes it possible to respond easily and quickly to any request in this concerning the desired end product

  (monofilar or strand of wires of very variable composition).

  In addition to the advantages mentioned above, the device according to the invention has a major economic interest. Indeed, since the beginning of the 1980s, the use of multi-wire machines of the prior art has become very widespread, which implied une20 under-use of existing single-wire machines These single-wire machines therefore risked becoming obsolete in the short term because of the technological change underway The device according to the invention therefore makes it possible to increase the duration of use and the amortization of single-wire machines The cost price of the products obtained from the device according to the invention is then lower than with the use of multi-wire machines of the art

  prior. Of course, the invention is not limited to the embodiment which has just been described.

  In particular, the device according to the invention may consist of any number of single-wire machines coupled together. Only one of these machines, the last for example, will be debtor and receiver at the same time. The winders of single-wire machines, and in particular the winding machine of the receiving machine, can be "static" In this 12 - case, these winders have no rotational movement around their axis, and it is for example an arm turning which brings the wire and wraps it around the winding machine Furthermore, the cutting is no longer ensured by a pulley, but by the translation along its axis of the winding machine itself. Advantageously, the single-wire machines used may or may not be equipped with a continuous annealer. In practice, the annealer causes a large number of breaks. In fact, the copper wire produced

  often has ferrous inclusions, for example.

  However, the annealing is carried out by Joule effect, and the ferrous inclusions are then the cause of localized heating causing the wire to break. Consequently, if the annealing is carried out for example statically, after the winding, the number of breaks decreases , which further increases the drawing speed reached and the yield of the device. In addition, the continuous annealing machine requiring a lot of maintenance, the "machine stop" times are frequent and relatively long and the maintenance cost is high. , a device without continuous annealers makes it possible to lower the cost price of the finished product and to increase the periods of use

keep on going.

  Furthermore, the single-wire machines used may include a drawing block operating either with stepped cones or with capstans. The control puppets used are of any known type. In the range of diameters 0.05 0.20 mm, it is nevertheless preferable to use "light control puppets" like that described in the

  Figure 3, while in the range of diameters 0.20 to 0.50 mm, usually used so-called "heavy" control jacks known to those skilled in the art.

  In addition, the puppet must have a low inertia so

  to be able to react as quickly as possible to any variation in the drawing speed.

  Finally, the systems for holding the wire (s) can also be installed on the internal idler pulleys, to

  provide even more effective support.

13 -

Claims (8)

  1 / Multi-wire drawing device, for the manufacture of a wick of metal wires, comprising a wire drawing line per wire of said wick, means for regulating the speed of wire drawing5 and the traction of said wires, then means for coupling of each of said drawn wires separately, in order to form said wick, and finally, means for uniformly distributing said wick on a main winder, characterized in that each of said drawing lines consists of a single-wire drawing machine10 comprising a block drawing, means, specific to said machine, for regulating the drawing speed and the traction of the wire drawn by said machine and a winding machine, only one of said single-wire machines, called receiving machine, being intended to receive on its winding machine, said main winder, said wick, said winders of other single-wire machines, called debit machines, not being not used, and said single-wire machines comprising   in addition each one means for coupling each of said wires drawn separately at a speed and traction regulated to the other wires in order to constitute said wick gradually being wound up uniformly on said main winder.   2 / Device according to claim 1, characterized in that, said single-wire machines being placed one after the other, the first machine being one of said debiting machines and the last said receiving machine, the first wire drawn separately from the first of said machines is sent via said coupling means of said first machine to the coupling means of said second machine which collects said first wire and the second wire drawn separately from the second machine, and so on until '' by means of coupling of said receiving machine which recovers said grouped wires from said debiting machines and the last drawn wire separately coming from   said receiving machine, said son thus grouped constituting said wick.   3 / Device according to one of claims 1 and 2, characterized in that   that said coupling means are orientable so that 14 - each of the wires drawn separately by said single-wire machines   can be directed to another line of multi-wire drawing.   4 / Device according to one of claims 1 to 3, characterized in that   that said single-wire regulation means is a dummy with diameters between 0.05 E / Device according to one of that said said single-wire regulation means is a dummy with diameters between 0.20 E 6 / Device according to one of , said main winder specific to each light regulation and 0.20 mm for the claims 1   suitable for each heavy regulation and 0.50 mm for the claims 1 of said machines in the range of thread produced.   to 4, characterized in that said machines for the range of thread produced.   5, characterized in that it is a dynamic winder, said means for uniformly distributing said wick on said winder   dynamic consist of a cutting pulley having a cutting pitch adapted to the width of said wick in order to constitute a uniform winding.   7 / Device according to one of claims 1 to 6, characterized in that, said main winder being a static winder, said means for uniformly distributing said wick on said static winder consist of a motor allowing said static winder to perform translational movements parallel to   its axis and at a speed adapted to the width of said wick in order to constitute a uniform winding. 8 / Device according to one of claims 1 to 7, characterized in that   that said means for coupling said wire drawn separately to the other wires drawn separately are external return pulleys secured to each of one of said single-wire machines. 9 / Device according to claim 8, characterized in that each of said external deflection pulleys is orientable and rotates around   a vertical axis tangent to its bottom of the groove.   / Device according to one of claims 8 and 9, characterized in that each of said external deflection pulleys is provided with a   system for holding said wire. 11 / Device according to claim 10, characterized in that said   said wire holding system is a pinching system by felt. -   12 / Device according to claim 10, characterized in that said system for holding said wire is a system for holding by eyelets.   13 / Device according to claim 10, characterized in that said holding system of said wire is a shell.   14 / Device according to one of claims 1 to 13, characterized in that each of said single-wire machines further comprises a   continuous annealer located between said drawing block and said regulating means. 15 / Wick obtained by the device according to claims 1 to 14,   characterized in that said wick is free from oxidation and can be used in particular for the manufacture of one of the products   such as strand and twist of flexible conductors, and shielding braid in cables.