A cabling machine

Abstract: The present invention relates to a cabling machine for laying optofibres, cables or the like in an oscillating, wavy path around a smooth pull-reliever or into grooves of oscillating, wavy shape extruded around a pull-reliever, so-called S/Z-cabling. The machine includes a pull-reliever reeling-off device, a braking capstan, a fibre reeling-off device or devices, an S/Z-bench for laying the fibre/fibres around the pull-reliever, a yarn spinner for fixating the fibre/fibres on the pull-reliever, and a wheel capstan and a taking-up device for forwardly pulling and taking-up the finished cable respectively, the S/Z-bench including a laying-on tube provided with a laying-on head, wherein the fibre/fibres pass over the laying-on tube and up to and through holes in the laying-on head, where they are laid on the pull-reliever and fixated with yarn taken from the yarn spinner located immediately downstream of the laying-on head. According to a first aspect of the invention, the S/Z-bench (6) includes an aligning mechanism (13) which grips around and guides the pull-reliever (2), and a motor (15) which imparts an oscillating, rotational movement to the aligning mechanism via a transmission (14). The laying-on tube (11) is fixed to or connected to the transmission (14) which imparts an oscillatory, rotational movement to the laying-on tube in a direction opposite to the aligning mechanism (13). A sensor (17) is connected to the transmission (14) and controls rotational movement of the motor (15) and therewith of the laying-on tube (11) and/or the aligning mechanism (13), wherein rotational movement of the laying-on tube is restricted so that the fibre/fibres (5) will only be wound onto the laying-on tube (11) to a small extent. According to another aspect of the invention, the pull-reliever reeling-off device (1) and the braking capstan (3) are rotatably mounted and the laying-on tube (11) is freely rotatable and guided by the action of laying the fibre/fibres (5) into the grooves in the pull-reliever (2). The laying-on tube (11) is connected to the transmission (14) and a sensor (17) is connected to the transmission and functions to detect rotation of the laying-on tube (11) caused by the oscillating waveshape of the grooves and causes the reeling-off device (1) and the braking capstan (3) to rotate to perform a correcting function and therewith counteract excessive rotation of the laying-on tube (11) so that the grooves in the pull-reliever (2) in the vicinity of the laying-on head will extend substantially rectilinearly and such that the fibre/fibres (5) extend substantially parallel with the laying-on tube.

Description: TECHNICAL FIELD The present invention relates to a cabling machine for laying optofibres, cables or the like in an oscillating wavy path around a smooth pull-reliever, or down into grooves of oscillating waveshape that have been extruded around a pull-reliever, so-called S/Z-cabling, said machine comprising a pull-reliever reeling-off device, a braking capstan, a fibre/fibres unreeling device, a S/Z-bench for laying the fibre/fibres around the pull-reliever, a yarn spinner for fixating the fibre/fibres on the pull-reliever, and a wheel capstan and a taking-up device for pulling the pull-reliever through the machine and taking-up the finished cable, wherein the S/Z-bench includes fibre-laying-on tube which is provided with a fibre-laying-on head, and wherein the fibre/fibres passes/pass over the laying-on tube up to and through holes provided in the laying-on head, where said fibre or fibres is or are laid on the pull-reliever and fixated with yarn taken from the yarn spinner located immediately downstream of the laying-on head. BACKGROUND ART Cabling machines for laying optofibres or the like in an oscillating, wavy path around a smooth pull-reliever are known to the art, for instance from US-A- 4,805,392, US-A- 4,676,054 or US-A- 4,833,871. These cabling machines include an S/Z-bench which includes a laying-on tube or discs which are oscillated backwards and forwards for the purpose of laying the fibres on the pull-reliever. The fibres, which pass along the laying-on tube to a laying-on head located on the forward end of said tube, become wound to a greater or lesser extent around the laying-on tube during operation of the machine, which causes the fibres to be subjected to friction forces. These frictional forces will vary in accordance with the rotational movement of the laying-on tube at that particular moment in time, and when the fibres are wound to a great extent on the tube, the frictional forces can be so high as to damage the fibres. Also known to the art are cabling machines which are intended to lay optofibres or the like in grooves of oscillating waveform extruded around a pull-reliever. These machines also include an S/Z-bench provided with a laying-on tube or discs over which the fibres pass to a laying-on head. The pull-reliever is pulled rectilinearly through the laying-on tube and, because of the oscillating form of the grooves, the tube tends to rotate forwards and backwards as a result of the fibres being guided down into the grooves. This rotational movement or twisting of the laying-on tube will also cause fibres to be wound around the tube and subjected to frictional forces that are liable to damage the fibres, similar to the former case. Thus, the known cabling machines have the disadvantage of subjecting fibres to large frictional forces with subsequent risk of damage to the fibres. Furthermore, the known machines are intended for laying fibres in an oscillating waveform, so-called S/Z-cabling, solely on one type of pull-reliever, namely either on a smooth pull-reliever or on a pull-reliever on which grooves have been pre-extruded. DISCLOSURE OF THE INVENTION The object of the present invention is to provide a cabling machine which will not subject the fibres to harmful frictional forces and which can also be readily switched between modes in which fibres can be laid on both smooth and grooved pull-relievers. This object is achieved with a cabling machine having the characterizing features set forth in the following Claims. The inventive cabling machine has the advantage of being usable for both types of pull-reliever and also of minimizing the risk of damage to the fibres, since the fibres pass over the laying-on tube in a frictionless fashion. This enables the fibres to be laid at a high production rate. Further objects of the inventive cabling machine and further advantages afforded thereby will be evident from the following, detailed description, in which the invention is described in more detail with reference to a preferred exemplifying embodiment thereof and also with reference to the accompanying drawings. BRIEF DISCLOSURE OF THE DRAWINGS Figure 1 illustrates schematically the construction of an inventive cabling machine. Figure 2 illustrates an S/Z-bench included in the cabling machine. Figure 3 illustrates a part of the S/Z-bench. BEST MODE OF CARRYING OUT THE INVENTION Figure 1 illustrates schematically the general construction of a cabling machine. The illustrated machine includes a reeling-off device 1 for reeling-off a pull-reliever 2, a braking capstan 3, unreeling devices 4 for reeling-off fibres 5 which are to be laid around the pull-reliever 2, an S/Z-bench 6, a yarn spinner 7 which is located immediately downstream of the S/Z-bench and which functions to fix the fibres on the pull-reliever, optionally a banding machine 8 for banding the fibre-laid cable to a finished cable, a wheel capstan 9 for drawing the cable forwards, and a coiling device 10 for coiling-up the finished cable. The reeling-off device 1 is provided with a basic braking arrangement, and the braking capstan 3 is provided with sensors for determining and setting the tension in the pull-reliever 2, this being necessary so as to obtain a sufficient fibre surplus which will enable the temperature-cycling requirement to be fulfilled. Both the reeling-off device 1 and the braking capstan 3 are rotatably mounted, for reasons made apparent herebelow. The fibre reeling-off devices 4 are arranged in a common station and include, in a known manner, basic braking arrangements, forwardly pulling devices and sensors for measuring and adjusting the tension in the fibres. The S/Z-bench 6 will now be described in more detail with reference to Figure 2. The S/Z-bench can be said to be the hub of the cabling machine and of the invention, and includes a fibre-laying-on tube 11 over which the fibres 5 pass from the reeling-off devices 4. The fibres 5 are guided to the S/Z-bench so as to be conducted concentrically over the laying-on tube 11 and up to a laying-on head 12 mounted on the outer end of the tube, where the fibres are guided and conducted down onto the pull-reliever 2 drawn through the laying-on tube. The laying-on head may be of any conventional kind and is only shown schematically in the Figure and will not be described in detail. The S/Z-bench 6 also includes an aligning mechanism 13, a transmission 14 capable of being driven by a reversable stepping motor 15, and an absolute sensor 17 connected to the transmission over gearing 16. The transmission 14 is illustrated in more detail in Figure 3. The transmission includes two toothed wheels 18 which are in mutual axial alignment and through which the pull-reliever 2 can pass. The aligning mechanism 13 can be non-rotatably connected to one toothed wheel by means of a key-joint or the like, and the laying-on tube 11 can be non-rotatably connected to the other toothed wheel. Two further toothed wheels 19 and 20 are mounted perpendicularly to and at different distances from the toothed wheels 18, of which further toothed wheels the tooth wheel 19 is connected to the motor 15 and the toothed wheel 20 is connected to the absolute sensor 17, via the gearing 16. An endless toothed belt 21 runs in a continuous loop over the toothed wheels 18, 19 and 20, the arrangement being such that when one toothed wheel 18 rotates in one direction, the other toothed wheel 18 will rotate in the opposite direction. In the illustrated embodiment, the gearing 16 comprises a smaller toothed wheel which is connected to the toothed wheel 20 and which drives a large toothed wheel connected to the sensor 17 via a toothed belt, although it will be understood that other types of gearing can be used. The gearing is intended to prevent the absolute sensor 17 from rotating more than one revolution. When cabling smooth pull-relievers 2, the reeling-off device 1 and the braking capstan 3 are both stationary, i.e. not rotatable. The aligning mechanism 13, which comprises a number of gripping wheels which grip around the pull-reliever 2 and guide the same through the aligning mechanism, is connected to the transmission 14. The stepping motor 15 is also connected to the transmission 14 and drives the transmission, and consequently also the aligning mechanism 13 and the pull-reliever 2, in an oscillating reciprocating rotary movement. This movement is regulated by the absolute sensor 17 via a regulating and controlling device. The fibres 5 will therefore be laid on the pull-reliever 2 in an oscillating waveform and are fixated with the aid of yarn taken from the yarn spinner 7 immediately downstream of the laying-on head 12. The yarn spinner 7 is preferably a double-yarn spinner with which the two yarns are laid in mutually opposite directions, thus in both an S-direction and a Z-direction. Because the laying-on tube 11 does not rotate when in operation, the fibres 5 will pass parallel through the tube, and hence the frictional forces acting on the fibres will be minimal. In accordance with an alternative embodiment, for cabling a smooth pull-reliever 2, the laying-on tube 11 may also be connected to the transmission 14. Because of the configuration of the transmission, both the aligning mechanism 13 and the laying-on tube 11 will, in this case, be imparted an oscillating, reciprocating rotary movement, although in different directions. Rotation is regulated by the absolute sensor 17 also in this case. Because of these counterdirectional rotary movements, the total rotation of the aligning mechanism 13 may be smaller than in the former case, while still laying the fibres in an oscillating waveform on the pull-reliever. Total rotation of the laying-on tube 11 is equal to the total rotation of the aligning mechanism 13, therewith limiting the extent to which fibres 5 become wound around the laying-on tube 11 and thus also limiting the frictional forces on the fibres. Cabling of grooved pull-relievers 2 will now be described. In this case, the aligning mechanism 13 is removed, the stepping motor 15 is disconnected, and the laying-on tube 11 is connected to the transmission 14. In this case, the reeling-off device 1 and the braking capstan 3 can be rotated to effect a correcting function. When the fibres 5 are laid into the oscillating, wave grooves in the pull-reliever 2, the laying-on tube 11 will tend to rotate. This rotation is detected by the absolute sensor 17 connected to the transmission 14, which now causes the reeling-off device 1 and the braking capstan 3 to rotate in a remedial or correcting fashion in response to the set turning-limits of the laying-on tube 11 such that the grooves in the pull-reliever 2 will extend substantially rectilinearly past the laying-on head 12. The laying-on tube 11 will thus only rotate or twist to a limited extent and consequently fibres 5 will not be wound onto the tube or subjected to frictional forces to any appreciable extent. In all of the aforedescribed alternative embodiments, it must be ensured that the free length of the pull-reliever 2, i.e. the distance between the braking capstan 3 and the wheel capstan 9, is sufficiently great to enable the pull-reliever to rotate about its longitudinal axis. It will be understood that the invention is not restricted to the aforedescribed and illustrated embodiment, and that modifications can be made within the scope of the accompanying Claims.

Claims: A cabling machine for laying optofibres, cables or the like in an oscillating, waveform around a smooth pull-reliever in a first application mode, or into oscillating, waveshape grooves extruded around a pull-reliever in a second application mode, both modes being of the so-called SZ-cabling type, said machine comprising a pull-reliever reeling-off device (1), a braking capstan (3), a fibre reeling-off device (4) or devices, an S/Z-bench for laying the fibre/fibres around the pull-reliever (2), a spinner (7) for fixating the fibre/fibres (5) on the pull-reliever (2), and a wheel capstan (9) and a taking-up device for forwardly pulling and taking-up the finished cable respectively, said S/Z-bench including a laying-on tube (11) provided with a laying-on head, wherein the fibre/fibres (5) pass over the laying-on tube (11) up to and through holes in the laying-on head, where they are laid on the pull-reliever (2) and characterized in that the spinner (7) is a yarn spinner and that the fibres are fixated with yarn taken from the yarn spinner located immediately downstream of the laying-on head, wherein the pull-reliever reeling-off device (1) and the braking capstan (3) are rotatably mounted round an axis parallel with the forwardly pulled pull-reliever (2), but are fixedly adjusted when using a smooth pull-reliever (2) and are rotationally controlled when using a groove extruded pull-reliever; in that the S/Z-bench (6) includes an aligning mechanism (13) which when using a smooth pull-reliever grips around and guides the pull-reliever (2), a transmission (14) and a motor (15) which through the transmission can drive the aligning mechanism (13) in an oscillatory, rotational movement, the transmission (14) including two mutually coaxial toothed wheels (18) through which the pull-reliever (2) passes, two mutually parallel, further toothed wheels (19, 20) spaced from and perpendicular to the first mentioned toothed wheels (18), and a toothed belt (21) which extends in a continuous loop around said toothed wheels (18, 19, 20), wherein the aligning mechanism (13) is connectable to one of the first mentioned toothed wheels (18) and the laying-on tube (11) can be connected to the other of said first mentioned toothed wheels (18); in that a sensor (17) is connected to the transmission, the sensor (17) being an absolute sensor and connected to the transmission (14) via extensive gearing (16); in that the laying-on tube (11) when using a smooth pull-reliever is fixed to or connected to the transmission (14) and is imparted an oscillatory, rotational movement by said transmission in a direction opposite to the rotational movement of the aligning mechanism (13), and when using a groove extruded pull-reliever is connected to the transmission (14) and is freely rotatable and is guided by the action of laying the fibre/fibres (5) into the grooves in the pull-reliever (2); the sensor when using a smooth pull-reliever controls the rotational movement of the motor (15) and therewith the rotational movement of the laying-on tube (11) and/or the aligning mechanism (13), wherein rotational movement of the laying-on tube is limited such that the fibre/fibres (5) will only be wound onto the laying-on tube (11) to a slight extent, so as to minimize the frictional forces acting on said tube, and the sensor when using a groove extruded pull-reliever functions to detect rotation caused by the oscillating, waveshape of the grooves in the laying-on tube (11) and causes the reeling-off device (1) and the braking capstan (3) to rotate and perform a correcting or remedial function which counteracts excessive rotation or twisting of the laying-on tube (11), such that the grooves in the pull-reliever (2) in the vicinity of the laying-on head will extend substantially rectilinearly and such that the fibre/fibres (5) will extend substantially parallel with the laying-on tube in the absence of friction thereagainst. A cabling machine according to Claim 1, characterized in that the motor (15) is a reversible stepping motor. A cabling machine according to Claim 2, characterized in that the aligning mechanism (13) includes a plurality of rollers which engage the pull-reliever (2) on diametrically opposite sides thereof. A cabling machine according to Claim 3, characterized in that a banding machine (8) is positioned upstream of the wheel capstan (9). A cabling machine according to Claim 4, characterized in that the yarn spinner (7) is a double yarn spinner with which the two yarns are laid in mutually opposite directions (S and Z). A cabling machine according to Claim 5, characterized in that the free length of the pull-reliever (2) between the braking capstan (3) and the wheel capstan (9) is sufficiently long to enable the pull-reliever to rotate about its longitudinal axis.

Inventors: NORTENIUS BENGT ARNE, NORTENIUS, BENGT ARNE
Applicants: ERICSSON TELEFON AB L M, TELEFONAKTIEBOLAGET L M ERICSSON
Application year: 1991
Main classification: G02B6
IPC codes: G02B6