Transfer of an elongated element from one spool to another spool

Abstract

An elongated element (10) is transferred from a second (full) spool (13) to a first (empty) spool (14). A gripper (16) is positioned on the elongated element (10). The gripper (16) catches the elongated element (10) and the elongated element (10) is cut between the gripper (16) and the second spool (13) thereby leaving a leading end (19). Thereafter the gripper (16) is positioned with the leading end (19) at the level of the first empty spool (14). The gripper (16) is rotating around the axis of the first spool (14) to form first windings to fix the elongated element (10) on the first spool (14). The method allows full automation and assures the use of the wound element (10) until its final end.

Claims

1. A method of transferring an elongated element from a second spool to a first spool, said method comprising the steps of: a. guiding the elongated element to the second spool; b. winding said elongated element on said second spool; c. providing the first spool adjacent to said second spool; d. positioning a gripper on said elongated element upstream of said second spool; e. gripping said elongated element by said gripper and cutting said elongated element between said gripper and said second spool, thereby leaving a leading end of said elongated element, without changing a linear supply speed of said elongated element; f. positioning said gripper with said leading end at a level of said first spool; g. rotating said gripper around an axis of said first spool to form first windings of said elongated element on said first spool and fixing said elongated element on said first spool; and h. causing said gripper to release said elongated element, wherein the elongated element is continuously supplied during transfer from the second spool to the first spool.

2. A method according to claim 1, wherein said first spool has a core and two flanges; and wherein fixing said elongated element on said first spool is done by at least one of glue, adhesive tape, a hole in the core of said first spool, a clip on the core or on one of the flanges of said first spool, bending the leading end of the elongated element and forming windings of the elongated element over said bent end, or any combination thereof.

3. A method according to claim 1, wherein said first spool is at a standstill during fixing of the elongated element on said first spool.

4. A method according to claim 3, wherein the elongated element is temporarily kept in an accumulator to provide a continuous supply of the elongated element.

5. A method according to claim 4, wherein said accumulator is formed by a guiding pulley which travels over a rail and keeps tension in the elongated element substantially constant.

6. A method according to claim 1, wherein said first spool is rotating at a rotational speed during fixing of the elongated element on said first spool such that a need for an accumulator is avoided.

7. A method according to claim 1, wherein steps a. to h. are repeated with a second spool instead of a first spool and a third spool instead of a second spool.

8. A method according to claim 1, wherein steps a. to h. are repeated with a second spool instead of a first spool and a first spool instead of a second spool.

9. A method according to claim 1, wherein said method is automated.

10. A method according to claim 1, wherein said first windings of said elongated element on said first spool are carried out under tension that is increased relative to tension applied during other winding to minimize loose ends during unwinding.

11. A method according to claim 1, wherein said first windings of said elongated element on said first spool are carried out under a first tension that is higher than a tension at which a subsequent winding is carried out.

12. A method according to claim 1, wherein said gripper comprises tungsten carbide.

13. A method according to claim 1, further comprising providing the gripper at a first location while the gripper rotates together with the first spool, and thereafter providing the gripper at a second location that is farther from the first spool than the first location.

Description

BRIEF DESCRIPTION OF FIGURES IN THE DRAWINGS

(1) FIG. 1a, FIG. 1b and FIG. 1c illustrate subsequent steps in a way of transferring a steel wire from one spool to an adjacent spool;

(2) FIG. 2a shows a front view of a frame where a gripper and a cutter are installed;

(3) FIG. 2b shows a side view of a gripper;

(4) FIG. 3 illustrates the way of working of a wire accumulator.

MODE(S) FOR CARRYING OUT THE INVENTION

(5) FIG. 1a illustrates a first step in a wire transfer from a spool to an adjacent spool.

(6) A steel wire 10 is guided over a pulley 11 and driven by a capstan 12 to be wound upon a second spool 13. Adjacent to the second spool 13 is a first and empty spool 14. The axes of the second spool 13 and of first spool 14 are parallel. Spools 13 and 14 are driven independently from one another. A little time before the second spool 13 is full or after an operator has given the instruction to transfer the wire 10, a wire gripper 16 is positioned downstream the capstan 12 close to the wire 10, e.g. by surrounding the wire 10. The gripper 16 is not yet touching or gripping the wire. The gripper may be made of a hard metal such as tungsten carbide.

(7) A cutter 18 is positioned downstream the gripper 16 ready to cut the wire 10.

(8) The position of the gripper 16 close to the steel wire 10, just before capturing the wire 10, may be determined optically or may be calculated after measuring the speed of supply of steel wire 10 and the rotation speed of the second spool 13. It is hereby understood that the lower this latter rotation speed is, the more full the spool 13 and the lower the angle the steel wire 10 makes with a horizontal line between the capstan 12 and the second spool 13.

(9) At a given moment the gripper 16 captures the steel wire 10 and the cutter 18 cuts the steel wire 10.

(10) FIG. 1b illustrates a second step in a wire transfer from a second spool 13 to a first spool 14 just after the steel wire 10 has been cut leaving a leading end 19 of the steel wire 10 at one end of the gripper 16. The gripper 16 travels with the steel wire 10 from second spool 13 to first spool 14.

(11) In a preferable embodiment of the invention, this travelling is at such a high speed that the linear supply speed of steel wire 10 remains unchanged and that there is no need for an accumulator.

(12) If this high travelling speed cannot be reached, an accumulator is preferably used so that the linear supply speed of steel wire 10 remains unchanged and that the processes upstream can be left untouched.

(13) FIG. 1c illustrates a third step in a wire transfer from a second spool 13 to a first spool 14.

(14) The gripper 16 rotates a few rotations together with the first spool in order to fix the steel wire 10 with its leading end 19 to the empty spool 14. As mentioned, this is preferably done under an increased winding tension.

(15) As also mentioned above, this fixing may be done in various ways.

(16) After a few rotations of the gripper 16 with the spool 14, the gripper 16 releases the steel wire 10 and takes a position more remote from the first spool 14.

(17) After this transfer of wire the second spool 13 filled with steel wire 10 may be removed and replaced by an empty spool.

(18) FIG. 2a and FIG. 2b illustrate how the movement and positioning of the gripper 16 and the cutter 18 may be realized.

(19) FIG. 2a shows a front view of a frame 20. This frame 20 can travel horizontally along the positions of the spools. The frame 20 may travel on wheels (not shown) or the frame 20 may be hung on a rail (not shown).

(20) A cutter basis 21 is installed via a support 22 on a vertical arm of the frame 20. Cutter 18 is connected to the cutter basis 21 (not shown). The cutter basis can travel vertically in the direction of arrows 23 along the arm of the frame 20. This vertical movement may be realized by means of rails or by means of wheels.

(21) The horizontal movement of the frame 20 together with the vertical movement of the cutter basis 21 allow to position the cutter 18 where it is desired.

(22) A gripper basis 24 is installed via a support 25 to another vertical arm of the frame 20. Gripper 16 is connected to this basis 24. The gripper basis 24 can travel vertically in the directions of arrows 26 along the arm of the frame 20. Gripper 16 is connected to its basis 24 via an arm 27 which may rotate in the direction of arrows 28.

(23) The horizontal movement of the frame 20 together with the vertical movement of gripper basis 24 allow to position the gripper 16 close to or around the steel wire 10. The rotational movement allows to perform a number of revolutions of the gripper 16 with a steel wire 10 around a spool.

(24) FIG. 2b gives a side view of the arrangement of gripper 16. As already mentioned, gripper 16 is connected through an arm 27 to a gripper basis 24. Arm 26 can rotate in the direction of arrow 28. A first part of arm 27 is positioned in line with the rotation axis of the first spool 14. A second part of arm 27 deviates from this axis line and allows gripper 16 to bring steel wire 10 over flange 14 to core 14 of first spool 14. Alternatively, the leading end of steel wire 10 may also be fixed to the inner side of the flange 14, preferably close to the core 14.

(25) Depending upon the way of fixing the leading end of the steel wire to the empty spool 14, empty spool 14 may stand still or may rotate at a lower speed than needed to take up all steel wire 10 without decreasing the supply speed of the steel wire 10. In this case a wire accumulator may be used.

(26) FIG. 3 illustrates the principal working of one type of wire accumulator.

(27) Steel wire 10 is driven by capstan 12 and is guided over a first fixed pulley 30 and makes a 180 turn over a travelling pulley 32. Via a second fixed pulley 38 the steel wire is brought to the first spool 14.

(28) Pulley 32 may travel horizontally, e.g. by means of its axe being positioned in a horizontal groove 36.

(29) During this horizontal travelling to the right side, the tension in steel wire 10 is kept constant and wire length is accumulated.

(30) During the travelling to the left side, the accumulated length of steel wire 10 is decreased, because the first spool 14 is rotating at a higher speed.

LIST OF REFERENCE NUMBERS

(31) 10 steel wire 11 guiding pulley 12 capstan 13 second (full) spool 14 first (empty) spool 14 flange of first spool 14 core of first spool 16 gripper 18 cutter 19 leading end of steel wire 20 frame 21 cutter basis 22 support 23 arrows indicating vertical direction 24 gripper basis 25 support 26 arrows indicating vertical direction 27 gripper arm 28 arrows indicating rotational movement 30 first fixed guiding pulley 32 travelling guiding pulley 34 axe of travelling guiding pulley 36 groove 38 second fixed guiding pulley