The invention relates to a device in accordance with the introductory part of claim 1, for the forming of coils (coiling) of strands, and a device for carrying out this method. "Strands" should be understood to include all forms of extended, flexible objects, such as tubes for electrical cables, with or without cables, electrical cables, flexible plastic tubes for water, hoses, and wires.

Background Flexible plastic tubes, e.g. for electrical cables, are normally delivered in lengths of 50 - 150 metres, in a package intended for opening of the site of use. It is important that such tubes are made available for use without twists. It has been proposed to coil such tubes on a reel, or similarly, to allow for a twist removal. But this will require an addition to the package, and will further require rotation of the reel. Such a package will also demand particular equipment for packaging. From US patent specification 2,447,982 (Koster 1945) it is known to provide yarn coils with a rotatable pipe through which the yarn is fed. The length of yarn exposed by pulling the yarn end from the coil will have twists. From US patent specification 2,971,243 (Burns 1960) a corresponding coiling machine is described, in which the pipe is replaced with an assembly of a pipe and guiding wheels on a linked arm. Neither will this allow pulling out of strands without twists. From US patent specification 2,895,210 (Hubbard 1955) it is known to arrange a strand in double loops in a package. This is unconvenient for strands with a certain thickness, e.g. plastic tubes and cables. From US patent specification 3,135,038 (Pflugrad 1962) it is known to coil strands in an annular compartment with a guiding pipe. This will not provide a satisfactory package which is easy to uncoil at the site of use.

From US patent specification 4,080,772 (Chambley 1978) it is known to use a rotatable tube elbow for introducing a strand material to a coiling compartment, in which coils are placed in an annular array. Neither will this proposal will provide a user friendly package.

Objects The main object of the invention is thus to provide a method for the packaging of strand material, which is coiled in a package, as well as a device for the packaging of such material, enabling unpackaging at a site of use without twists, i.e. with linear withdrawal. The packaging is to be carried out with reliable equipment, and with high velocity. The Invention The method, according to the invention is described in claim 1, while a practical device for carrying out this method is described in claim 4. Further features of the invention are described in claims 2 - 3 and 5 - 8.

Examples Below, the invention is described in more detail with reference to an example, where: Figure 1 schematically shows a perspective view of an embodiment of a device according to the invention, for coiling of flexible plastic tubes, Figure 2 shows a vertical section through the coiling compartment of Figure 1, Figure 3 shows a perspective view of a locking pin unit to be mounted in the coiling compartment, Figure 4 shows a perspective view of the coiling unit of Figure 1, Figure 5 shows a perspective view of a turning head of Figure 1, with its support, Figure 6 shows a perspective view of a sliding arm at the edge of the coiling compartment, while Figure 7 shows how the reversed coils a, b, c are straightened at the release of the tube from the package.

The equipment of the example include the following elements: - a support 1 1 with a support plate 13, - a coiling compartment 16 integrated in the support 11, - a coiling unit 15 with a supply mechanism 23, - a turning head 27 on a carrying arm 26, where the arm is operated to change the coiling direction, - two or more locking pins 62 arranged external to the coiling compartment, - two or more packing arms 29, 30, - a sliding arm 28 adjoining the coiling compartment 16 to assist the coiling, - two or more locking pins 44 for locking coiled material, and - a control unit (not shown) to control the various motors and power units,

Figure 1 shows a support 11 with a cylindrical core 12, an upper support plate 13 and a carrying bracket 14 extending from the cylindrical core 12. Central in the support 1 1, a tubular, upwardly open coiling compartment 16 is arranged, with a vertical axis and a central, cylindrical core element 17, with a diameter of about 1/3 of the diameter of the coiling compartment. Details of the coiling compartment 16 will be further described in the following. Above the support 1 1, a coiling unit 15 with a carrying bracket 18, for attachment to an external carrier (not shown) is arranged. The bracket is carrying a horizontally extending arm 19, which, at the outer end, is linked to a pivoting arm 20 with a pivoting motor 21 at the link. The pivoting arm 20, carries at its outer end, a mounting plate 22 for a feeding mechanism 23, which will be further described with reference to Figure 4. At the link, a slot 24 is arranged to provide an end stop for the pivoting arm 20. Above the coiling unit 15, a J-shaped guide tube 25, for feeding material to be packed, is attached. This will be further described in the following. In front of the coiling unit 15, a turning head 27 on a carrying arm 26 is arranged. The term "turning unit" is linked to the function of this unit at the formulations of coils, during which it is turning the coils alternately. Between the coiling compartment 16 and the carrying arm 26 for the turning head 27, a sliding arm 28 as shown in Figure 5 is arranged. Under the coiling unit 15, two packing arms 29 and 30, making a mutual angle and being pivotable into the coiling compartment 16, are arranged for pressing the coiled material. Each packing arm 29, 30 includes a pivotable knee lever 31, being linked to a linear motor, which in the example, is a pneumatic cylinder 32. At the lower edge of the cylindrical core 12, a motor 33, for the lifting and lowering of the bottom of the coiling compartment 16, is arranged, as will be described with reference to Figure 2. Under the support plate 13, at the upper end of the cylindrical core 12, two locking pin units 34, 35 are arranged, which will be described further with reference to Figure 3. Said locking pins are directed radially to the coiling compartment 16 at a mutual angle. The described device has a control unit, end switches, air hoses, valves and other elements not shown, to control the operation of the device. Figure 2 shows the internal parts of the coiling compartment 16. The coiling compartment 16 is restricted in depth by a movable, annular base 36 carried by a guide tube 37, which is telescopically slidable on the core element 17. On one side of the guide tube 37, an axial feeding screw 38 is arranged, which at the lower end carries a driving wheel 39, to be driven with a driving belt 40 by the motor 33. The feeding screw 38 is connected to the guide tube 37 by a nut 41 attached to the lower end of the guide tube. The core element 17 is attached to the cylindrical core 12 at the lower end, with an annular bottom 42 and strengthening ribs 43. Figure 3 shows a locking pin unit 34 for arrangement at the upper end of the coiling compartment 16. Each unit includes a locking pin 44 which is extended into the coiling compartment, over the coiled material, with a linear motor, which in the example, is in the form of an air cylinder 45. The locking pin 44 is also guided axially in a longitudinal slot 46 in the cylindrical core 12, by a further linear motor 47, with two guiding rods 48, 49. In this manner, the coiled material will be pressed and maintained in the coiling compartment 16, against the inherent elasticity, which strives to open the coils. Figure 4 shows details of the feeding mechanism 23 for strand material to be coiled. The feeding mechanism 23 is arranged on the mounting plate 22 at the end of the pivoting arm 20. It includes a grooved pulley 50 arranged rotatably coupled onto the mounting plate 22, adjacent to the outlet end 51 of the guide tube 25. A sector of the grooved pulley 50 is covered by a guide belt 52, running in a loop over a pair of carrying wheels 53, 54 , the higher of the two being powered by a motor 55, both carrying wheels 53, 54 being carried by the mounting plate 22. The guide tube 25 is carried by a sleeve 56, which is attached to the pivoting arm 20. At the outlet of the sector of the grooved pulley 50 covered by the guide belt 52, a pivoting pin 57 is carrying a lower guiding arm 58 with a curved guide track, and a pair of side flanges 60, 61, which are guiding the strand material toward the turning head 27. The outer end of the side flanges 60, 61 is covered by a curved cover 62, making the guide arm 58 tubular with an outlet opening 64. The pivoting pin 57 and therewith the guide arm 58 is pivoted cyclically by a linear motor, such as a pneumatic cylinder 65 operating the pivoting pin 57 by a linked lever 66. Figure 5 shows the turning head 27 on the carrying arm 26, and an embodiment of a driving unit 67. The driving unit 67 includes a turning head carrying plate 68, attached to the support plate 13, with an inclined socket 69, which is a housing for a motor 70, extending beneath the support plate 13. The turning head carrying plate 68 carries a pair of pivoting pins 71, 72, each with a parallel arm 73, 74, which, at the outer end carry an intermediate arm 75. The intermediate arm 75 carries the carrying arm 26 of the turning head 27, with a bracket 76, said carrying arm 26 extending a curved C-shape, generally concentrically to the coiling compartment 16. The outer end 77 of the carrying arm 26, is linear and is inclined to the coiling compartment 16, the end carrying a cylindrical body extending perpendicularly to the carrying arms 26 end and forming the turning head 27. The motor 70 will pivot the turning head 27 cyclically in an orbit over the coiling compartment 16, and back to its retracted position by operation of the arms 73, 74, 75, 26, 77. A pneumatic cylinder 78 is linked to the bracket 76, and is connected to one end of a pivoting lever 79. The lever 79 has a link 80 at the transition between the arced and linear part of the carrying arm 26. The linear pivoting lever 79 at its outer end carries a disk 81 with an opening, where the disk is movable on the turning head 27, enabling movement of the disk by the pivoting lever 79 from an inner position at the inner edge of the turning head 27 to an outer position at its outer edge. The purpose of the disk 81, and its movement is to push the strand material, when this has to change coiling direction during the feeding to the coiling compartment. Figure 6 shows a sliding arm 28 arranged adjacent to the coiling compartment 16. The sliding arm 28 includes a curved plate 88, carried by one leg 83 of an L-lever 82. The second leg 84, at its outer end, is linked to a linear motor, such as a pneumatic cylinder 85. The elbow 86 of the L- lever 82, as well as the fixed end 87 of the pneumatic cylinder 85, is linked to the support plate 13. The curved plate 81 can thus slide coils over the center of the coiling compartment.

Function At the beginning of a feeding cycle, the pivoting arm 20, as well as the guide arm 58 and the turning head 27, are in their upper position. The strand material, e.g. a flexible tube for electrical cables, is introduced through the feeding tube 25, past the grooved pulley 50, and though the guide arm 58, and over the turning head 27 into the coiling compartment, with a first direction of coiling, which may be clockwise. For cyclical operation of this device, the turning head 27 will change the direction of coiling for each second coil deposited, to make the first coil a, and the third coil c, omni-directional, and the second coil b, counter-directional, as shown in Figure 7. The motor 33 and the movable bottom 36 can lift coiled material from the coiling compartment 16 into a package.