The present invention relates to a method of winding a wire-like product, such as a cable, on a flanged reel in a winding machine, wherein

- the reel is supported rotatably about its axis by means of a support structure;

- the cable is passed on the reel to form superimposed layers of adjacent cable turns wound between reel flanges by means of a guide;

- the support structure and the guide are dis¬ placed with respect to each other with a pitch cor¬ responding to the cable thickness per one cable turn, - the cable being wound on the reel at an angle of lag with respect to adjacent cable turns, which angle is changed at each reel flange through a posi¬ tion parallel with the flange into an opposite angle of lag when a cable turn comes into contact with the reel flange.

As used in this connection, the expression "wire-like product" refers to all kinds of long narrow continuous objects which can be wound on a reel, such as cables, conductors, and hoses, mainly products used in the manufacture of electric cables and data transmission conductors. For the sake of clarity, however, the invention will be described below with reference to a cable.

When a cable is wound on a reel or drum, a guide is used so that the cable will be positioned between the flanges of the reel in superimposed laye¬ rs each comprising a number of adjacent cable turns.

In most prior art winding machines, e.g. U.S. Patent Specifications 4,143,834 (FURUKAWA), 4,150,801 (KOBE STEEL), and 3,997,128 (FURUKAWA), the winding

movements are effected by axially displacing the cable guide and the reel with respect to each other in the axial direction of the reel in such a way that when the reel accomplishes one revolution, the guide or the reel is displaced a distance equal to the thickness of the cable. The prior art winding machines are normally adjustable for handling reels having different drum diameters and different dis¬ tances between the reel ends. The machines are also provided with a distributing machinery, by means of which the axial displacement between the guide and the reel for each revolution of the reel, i.e. the pitch at which the cable is wound on the reel, can be adjusted so that it always corresponds to the thick- ness of the cable to be wound.

It is well-known in the cable manufacture that the best and densest winding result on the reel is obtained when the cable to be wound forms an oblique angle of lag with respect to the axis of the reel during the winding.

It is also well-known that it is advantageous that the product to be wound is directed in parallel with the reel flange when a reeled cable turn comes into contact with the flange, i.e. that the angle of lag is reduced to zero. Swedish Patent Application 9000662 (NOKIA-MAILLEFER) discloses a winding machine in which the angle of lag is reduced to zero, that is, the cable is wound at right angles to the axis of the reel and in parallel with the reel flange by means of a simple rotatable pair of rollers. German Auslegeschrift 1 902 722 (ROSENDAHL) discloses a winding machine in which the reduction of the angle of lag to zero at the reel flange and its restoration to its proper value after the reversion of the direction of the displacing movement of the guide is

performed by accelerating/retarding the displacing

'», movement of the guide with respect to the reel.

A drawback of the above-mentioned winding methods and machines is that it is still difficult to 5 wind the cable sufficiently densely at the critical reel flanges, where the direction of the guide is reversed and the cable starts a new layer upon the previous ones.

The object of the present invention is to

10 provide a winding method which avoids the above- mentioned drawback and enables the cable to be wound- densely and without disturbances even close to the reel flanges. This is achieved by means of a method which is characterized in that the angle of lag is

15 changed into the position parallel with the flange before the cable turn comes into contact with the reel flange.

The method according to the invention is based on the idea that the angle of lag of the cable is

20 reduced to zero, that is, the winding of the cable on the reel at right angles to the reel axis is started preferably several cable turns before the cable comes into contact with the reel flange and the guide reaches its turning point. In this way the cable has

25 time enough to assume a position parallel with the flange before the flange forces it into the parallel position.

The invention also relates to a device in a winding machine, and this device is characterized in

30 that the winding machine comprises detecting means for each reel flange for detecting the reel flange and changing the angle of lag into said parallel po¬ sition before the reversing means detect the reel flange and reverse the direction of displacement of

35 the guide with respect to the reel.

Swedish Patent Application 9002141 (NOKIA- MAILLEFER) relates to a winding machine provided with sensing means for continuously sensing the cable thickness and for controlling the reversion of the displacement of the guide in the axial direction of the reel in response to the sensing movements of the sensing means. In this way the location of the turn¬ ing points of the guide at the reel flanges can be adapted to possible variations in the cable thick- ness.

In a preferred embodiment of the device accord¬ ing to the invention, the detecting means for re¬ setting the angle of lag are arranged to be displaced in the axial direction of the reel in synchronization with the movements of the sensing means due to variations in the cable thickness.

When using the device according to the inven¬ tion, the turning points of the guide need not be calculated and no manual adjustments are needed with different reel dimensions and reel widths, but the device automatically determines the appropriate turn¬ ing points and the appropriate angle resetting points with mechanical means both when winding cables with different diameters and cables with a varying dia- meter.

In the following the invention will be de¬ scribed more closely with reference to the attached drawings, in which

Figures 1A to 1C illustrate schematically the basic idea of the present invention;

Figure 2 is a perspective view of an arrange¬ ment according to the invention when applied to a prior art cable winding machine according to Swedish Patent Application 9002141; Figure 3 is an enlarged vertical view of the

guide of the winding machine;

<% Figure 4 is a considerably simplified top view of the guide; and

Figure 5 illustrates the cooperation between 5 the guide, the distributing machinery, the support structure and the reel;

Figure 6 illustrates the variation of the signal voltage according to the angle of lag in six different angle positions; and 10 Figure 7 illustrates diagrammatically the signal voltage of the distributing machinery as a function of the displacing time of the guide.

Figures 1A to 1C, which illustrate the idea of the invention, show a reel 1 on which a cable 2 is 15 wound between reel flanges la by means of a guide 3. The reel and the guide are displaced with respect to each other in the axial direction of the reel so that the cable will be wound turn by turn on the previous¬ ly wound cable layers. When the cable reaches a reel 20 flange, the direction of movement of the guide is reversed.

The guide is provided with two detectors 4 and

5, of which the detector 4 closer to the cable

. detects the presence of the reel flange in line with

25 the outer side of the cable while the other detector

5 detects the presence of the reel flange already before the first detector 4. The purpose of the detector 4 is to give a signal for reversing the direction of the displacing movement of the guide.

30 The purpose of the detector 5 is to give a signal for setting the angle of lag of the cable to zero.

In Figure 1A, the cable is wound on the reel at a certain angle of lag A so that the guide has a cor¬ responding lag with respect to a point B on the reel 35 at which the cable runs beside a previously wound

cable turn.

In Figure IB, the second detector 5 has detect¬ ed the reel flange and caused the displacing movement of the guide to be accelerated so that the lag of the guide is eliminated and the guide reaches such a position with respect to the entering point B of the cable on the reel that the angle of lag of the cable is zero. In this position the cable is wound at right angles to the reel axis and in parallel with the reel flange.

In Figure 1C, the cable has been further wound on the reel without any angle of lag until the first detector 4 detects the reel flange when the cable comes into contact with the reel flange and causes the direction of the displacing movement of the guide to be reversed. After a few cable turns have been wound on the reel without any angle of lag, i.e. in parallel with the reel flange, the displacing move¬ ment of the guide is retarded so that the guide again begins to lag, and the cable is wound on the reel at a desired angle of lag A. This is shown by broken lines in Figure 1C.

The guide has, of course, a similar pair of detectors for the other reel flange. The winding machine shown in Figure 2 mainly comprises a support structure 6 for a reel 1 and a guide 3 for a cable 2 to be wound on the reel. The guide is supported by a stationary bracing 7, whereas the support structure is wheeled and displaceable along rails 8 by means of a distributing machinery shown only schematically with the reference numeral 9. The reel is axially displaceable by means of the distributing machinery to and fro in front of the guide so that the cable will be wound on the reel turn by turn in superimposed layers between the ends

la of the reel. This type of winding machine is pre¬ viously known and therefore will not be described more closely below (e.g. SE Patent Application 9000662). The guide 3 shown in Figures 3 and 4 comprises a frame 10 in which a V-shaped guide roll 11 is mounted rotatably on a shaft transverse to the longitudinal direction of the cable. The guide further comprises two measuring rolls 12 which are fastened on the opposite sides of the cable by means of supports 13 arranged slideably on shafts 14 paral¬ lel with the shaft of the guide roll. Both supports support a signal generator 15 formed by an electric slide rheostat having one element 15b attached to the frame and another element 15a attached to the support.

Both supports further support two detectors 4 and 5 which correspond to the detectors shown in Figures 1A to 1C, that is, the detector 4 for revers- ing the direction of the displacing movement of the guide, and the detector 5 for setting the angle of lag of the cable to zero.

The signal generators 15 are connected to the distributing machinery 9 by means of cables 16, Figure 5. The signal generators respond continuously to variations in the thickness of the cable via the measuring rolls and sends electric signals through the cables 16 to the distributing machinery in order to cause a corresponding increase or decrease in the axial displacement of the reel per one cable turn by means of calculators and processors.

The detectors 5, e.g. photocells, are connected by means of cables 20 to the distributing machinery 9. When the detector detects the reel flange la, it sends a signal through the cable to the distributing

machinery to increase the axial displacement of the reel per one cable turn (when the winding of the cable takes place towards the reel flange) or to de¬ crease the displacement of the reel (when the winding of the cable takes place in a direction away from the reel flange) in an amount such that the angle of lag of the cable is set to zero or reaches a desired value, respectively. The angle of lag can be determined by means of the signal generators 15 in the following way:

The signal generators 15 generate a signal voltage U _x and U ₂ , respectively, Figure 5. When the angle of lag is zero, the voltages are equal, and the difference U = U _x - U ₂ = 0, as shown in Figure 6, in the situations B and E. The difference U _x - U ₂ is pro¬ portional to the angle of lag of the cable. When the difference U = U- _^ - U ₂ is positive, the angle of lag of the cable is opposite to the angle at which the difference U = U- - U ₂ is negative, as shown in Figure 6, in the situations A and D.

The distributing machinery 9 gives a set value U _B for the signal voltage U _x - U ₂ during the winding of the cable, as shown in Figure 7, which set value cor¬ responds to the desired angle of lag of the cable. The distributing machinery also gives a set value U^ for the signal voltage U ₁ - U ₂ when the cable is wound at right angles to the axis of the reel.

Alternatively, the sensing of the cable thick¬ ness may be carried out by means of the measuring rolls 12, which are connected to the signal generators 15. The sum of the signal voltages U _l and U ₂ , that is, the actual value U for the signal volt¬ ages U _x + U ₂ , is proportional to the cable thickness.

The detectors 4, such as photocells, are con- nected by means of cables 21 to the distributing

machinery 9. When the detector detects the reel flange, it sends an electric signal to the distributing machinery to cause it to reverse the direction of the displacing movement of the reel. The drawings and the description related to them are only intended to illustrate the idea of the invention. In its details, the invention may vary within the scope of the claims. The method and the device according to the invention may also be applied in winding machines having no means for sensing variations in the cable thickness, and in machines where the direction of the displacing movement of the guide or the reel is reversed by devices different from those described herein. In place of using a displaceable reel and a stationary guide, as in Figures 2 to 5, the reel may be stationary and the guide displaceable. The guide means for setting the angle of lag of the cable to zero and resetting it to a predetermined angle may also be mechanical means supported by the guide, e.g. of the type shown in Swedish Patent Application 9000662. The signal generators 15 may also be analogous ultrasonic measuring means or analogous optical IR measuring means.