Method for removing insulation from inner conductors of a cable, and stripping device

Abstract

A method for removing insulation from inner conductors of a cable having a first section with a cable sheath removed and a second section with the cable sheath not removed utilizes a stripping device to perform the following steps: inserting the first section between a first rotatable roller and a second rotatable roller of the stripping device; moving the first roller and/or the second roller toward each other to clamp the first section between the rollers; moving the cable in a first direction that moves the second section away from the rollers; moving the cable in a second direction opposite the first direction that moves the second section toward the rollers; moving stripping blades toward the first section to cut into the insulation of the inner conductors; and moving the cable in the first direction to remove at least part of the insulation from the inner conductors.

Claims

1. A method for removing insulation from a plurality of inner conductors inside a sheath of a cable comprising the steps of: providing a stripping device having stripping blades and first and second rollers, each of the first and second rollers being rotatable about a respective axis and being movable towards and away from each other; providing the cable with a first section in which the cable sheath is removed and a second section in which the cable sheath is not removed; inserting the first section between the first and second rollers; moving at least one of the first roller and the second roller such that the first and second rollers clamp the first section between the first and second rollers; moving the cable in a first direction such that the second section moves away from the first and second rollers while the first section is clamped between the first and second rollers; moving the cable in a second direction opposite the first direction such that the second section moves toward the first and second rollers while the first section is clamped between the first and second rollers; moving the stripping blades towards the first section such that the stripping blades cut into the insulation of the inner conductors; and moving the cable in the first direction to remove at least part of the insulation from the inner conductors.

2. The method according to claim 1 wherein a pressure with which the first and second rollers clamp the first section is increased after the cable has been moved in the first direction and before the cable is moved in the second direction.

3. The method according to claim 1 wherein the stripping blades and cutting blades for cutting the cable are included on a cutter head, and including a step of moving the cutter head in a direction perpendicular to the first direction to arrange the first section between the stripping blades.

4. The method according to claim 1 wherein during the clamping of the first portion between the first and second rollers, the first and second rollers are each moved toward one another.

5. The method according to claim 1 wherein a pressure with which the first and second rollers clamp the first section is a function of a distance between the first and second rollers.

6. The method according to claim 1 wherein a pressure with which the first and second rollers clamp the first section is pneumatically adjusted independently of a distance between the first and second rollers.

7. The method according to claim 1 including moving the cable multiple times alternately in the first direction and the second direction while the first section is clamped between the first and second rollers.

8. The method according to claim 1 including moving the cable alternately in the first direction and the second direction until the inner conductors are arranged in one plane.

9. A stripping device for removing insulation from inner conductors inside a sheath of a cable having a first section in which the cable sheath is removed and a second section in which the cable sheath is not removed, the stripping device comprising: a rotatable first roller and a rotatable second roller adapted to clamp the first section of the cable between the first roller and the second roller; a moving device for moving the cable in a first direction and then in a second direction opposite to the first direction while the first section is clamped between the first and second rollers; wherein during movement of the cable in the first direction, the second section is moved away from the first and second rollers and during movement of the cable in the second direction, the second section is moved toward the first and second rollers; and stripping blades for removing the insulation of the inner conductors, wherein the stripping blades are arranged to cut into the insulation of the inner conductors whereby the insulation is removed from the inner conductors when the cable is moved in the first direction.

10. The stripping device according to claim 9 including a cutter head having the stripping blades and cutting blades thereon, wherein the cutter head is movable in a direction perpendicular to the first direction such that the first section extends between the stripping blades.

11. The stripping device according to claim 9 wherein the first and second rollers are movable towards one another in opposite directions of movement to clamp the first section.

12. The stripping device according to claim 9 wherein a pressure with which the first and second rollers clamp the first section can be increased while the first section is clamped between the first and seconds rollers by moving at least one of the first and second rollers, wherein the pressure with which the first and second rollers clamp the first section is a function of a distance between the first and second rollers.

13. The stripping device according to claim 9 wherein a pressure with which the first and second rollers clamp the first section can be increased by an actuator coupled to at least one of the first and second rollers without substantially changing a distance between the first and second rollers while the first section is clamped between the first and second rollers.

14. The stripping device according to claim 9 wherein the moving device is adapted to move the cable multiple times alternately in the first direction and the second direction while the first section is clamped between the first and second rollers.

15. The stripping device according to claim 9 wherein the moving device is adapted to move the cable alternately in the first direction and the second direction until the inner conductors are arranged in one plane.

Description

DESCRIPTION OF THE DRAWINGS

(1) The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:

(2) FIG. 1 shows a perspective view of an embodiment of the stripping device according to the invention;

(3) FIG. 2 shows a perspective view of a cable with a plurality of inner conductors of which the cable sheath is removed in a first section;

(4) FIG. 3 shows a frontal view of the blade block of the stripping device of FIG. 1;

(5) FIG. 4 shows a side view of the stripping device of FIG. 1 during the first method step;

(6) FIG. 5 shows a perspective view of the stripping device of FIG. 1 during the first method step;

(7) FIG. 6 shows a side view of the stripping device of FIG. 1 during the second method step;

(8) FIG. 7 shows a side view of the stripping device of FIG. 1 during the third method step;

(9) FIG. 8 shows a side view of the stripping device of FIG. 1 during the fourth method step;

(10) FIG. 9 shows a side view of the stripping device of FIG. 1 during the fifth method step; and

(11) FIG. 10 shows a perspective view of the stripping device of FIG. 1 during the fifth method step.

(12) The figures are merely schematic and not true to scale. Identical reference signs in the different figures indicate features that are identical or have the same effect.

DETAILED DESCRIPTION

(13) The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.

(14) FIG. 1 shows a perspective view of an embodiment of the stripping device 5 according to the invention. FIG. 2 shows a perspective view of a cable 10 with a plurality of inner conductors 30, 31, of which the cable sheath 20 is removed in a first section 12. FIG. 3 shows a frontal view of the blade block of the stripping device 5 of FIG. 1.

(15) In FIG. 3, so to speak, the blade block is viewed from the left side of FIG. 1.

(16) The stripping device 5 is designed for removing the insulation 38 from a plurality of inner conductors 30, 31 of a cable 10. The cable 10 usually comprises a cable sheath 20, which typically has one or more outer insulation layers. The cable sheath 20 may contain additional layers, such as shielding fabric or foils.

(17) The cable 10 has a plurality of inner conductors 30, 31 or cores. This means that cable 10 is a multicore cable. The inner conductors 30, 31 can be twisted together as illustrated in FIG. 4. However, it is also possible that the inner conductors 30, 31 or cores of the cable 10 run parallel to each other, as illustrated in FIG. 2. This means that it is possible that the inner conductors 30, 31 are not twisted together.

(18) The inner conductors 30, 31, in turn, may have a plurality of strands 35, 36. The plurality of strands 35, 36 may be twisted together. It is also possible that the strands 35, 36 are not twisted together.

(19) In the case of cable 10, the cable sheath 20 was removed in a first section 12 of the cable 10, so that the inner conductors 30, 31, which each have insulation 38, are exposed. In FIG. 2 the first section 12 of cable 10 is located on the left. In a second section 14 of cable 10, the cable sheath 20 is still present. In FIG. 2, the second section 14 of cable 10 is located on the right.

(20) The cable sheath 20 may have been removed in the first section 12 of cable 10 by means of the stripping device. It is also possible that the cable sheath 20 was removed manually or with another device in the first section 12 of cable 10.

(21) The stripping device 5 has a blade block comprising an upper cutting blade 46, a lower cutting blade 48, an upper stripping blade 42 and a lower stripping blade 44 as shown in FIG. 1. The two stripping blades 42, 44 each have external projections, so that when the stripping blades 42, 44 are closing, a rectangle is formed in a plane perpendicular to the longitudinal axis of the cable 10. The longitudinal axis of the cable 10 extends into and out of the drawing plane in FIG. 3. The cable 10 extends through this rectangle when the stripping blades 42, 44 are used.

(22) The cutting blades 46, 48 are each V-shaped, so that when the cutting blades 46, 48 are closing, an opening formed by parts of the cutting blades 46, 48 is created in a plane perpendicular to the longitudinal axis of the cable 10. The cable 10 extends through these openings when the cutting blades 46, 48 are used.

(23) The cutting blades 46, 48 are designed for severing or cutting through the cable 10 or the inner conductors 30, 31. However, it would also be conceivable to use the cutting blades 46, 48 to cut into the cable sheath 20 and use the cutting blades to remove the sheath.

(24) The stripping blades 42, 44 each have a plurality of projections and recesses. This means that the stripping blades 42, 44 each have a zigzag shape on their cutting edge facing the cable 10. The projections and recesses of the upper stripping blades 42, 44 can be designed to be complementary to the projections and recesses of the lower stripping blades 42, 44. The number of projections or recesses can correspond to the (maximum) number of inner conductors 30, 31, so that there is a notch or recess of the second stripping blade 42, 44 for each inner conductor 30, 31. The stripping blades 42, 44 are used to cut or cut into the insulation 38 of the inner conductors 30, 31.

(25) The cutter head 40 can be moved in a plane perpendicular to the longitudinal direction of the cable 10 (in FIG. 3 to the left or right). This means that the cutter head 40 can be moved into such a position that when the cutter head 40 is closing, the cutting blades 46, 48 cut through the cable 10 or that when the cutter head 40 is closing, the stripping blades 42, 44 cut into the insulation 38 of the inner conductors 30, 31. Thus, the cable 10 is arranged either between the stripping blades 42, 44 or between the cutting blades 46, 48.

(26) In the drawings, the cutter head 40 is always arranged such that the cable 10 is arranged between the stripping blades 42, 44.

(27) The stripping device 5 has a first roller 60 or upper roller and a second roller 62 or lower roller. The rollers 60, 62 can be designed as cylinders. The rollers 60, 62 can each rotate around their horizontal axis. The rollers 60, 62 in FIG. 3 are arranged further to the right than the stripping blades 42, 44. The closing movement of the cutter head 40 moves the rollers 60, 62 towards each other. This means that when closing the cutter head 40 or moving the upper part and the lower part of the cutter head 40 towards each other, the rollers 60, 62 are also moved towards each other. The rollers 60, 62 are acted on by a plurality of compression springs 50, 52. The compression springs 50, 52 generate the clamping force on the first section 12 of the cable 10 when the cable 10 is clamped between the rollers 60, 62, wherein the clamping force is a function of the distance between the two rollers 60, 62. The further the stripping blades 42, 44 are closed, the more the rollers 60, 62 press on the first section 12 of the cable 10.

(28) It is also conceivable that the rollers 60, 62 have a closing device that is independent of the stripping blades 42, 44. The closing device can have a pneumatic cylinder, for example. Hereby, the clamping force of the rollers 60, 62 on the first section 12 of cable 10 can be changed independently of the distance between the rollers 60, 62. As shown in FIG. 3, a pneumatic actuator 64 can be coupled to move the rollers 60, 62 independent of the stripping blades 42, 44.

(29) The rollers 60, 62 can substantially only move upwards (away from each other) and downwards (towards each other). A lateral movement of the rollers 60, 62 is not provided.

(30) In the following, the process flow of the method for removing the insulation 38 or insulation from inner conductors 30, 31 or cores of the cable 10 is explained.

(31) FIG. 4 shows a side view of the stripping device 5 of FIG. 1 during the first method step. FIG. 5 shows a perspective view of the stripping device 5 of FIG. 1 during the first method step.

(32) First, a cable 10 with a plurality of inner conductors 30, 31 is provided, wherein the cable sheath 20 has already been removed from the cable 10 in a first section 12 (cf. FIG. 2). The inner conductors 30, 31 can be twisted together (cf. FIG. 4) or, as shown in FIG. 2, not twisted together. In a second section 14, the cable sheath 20 is still present on cable 10.

(33) The cable 10 is guided with its first section 12 between the stripping blades 42, 44. Then the cutter head 40 is closed far enough that the first section 12 or a section of the first section 12 of the cable 10 is clamped between the two rollers 60, 62. The rollers 60, 62 now press in opposite directions on the inner conductors 30, 31 of the cable 10. This pressing or the forces is/are shown by two arrows in FIG. 4.

(34) In FIG. 4 the cable 10 is guided between the rollers 60, 62 so deep that the cable sheath 20 of the second section 14 almost touches the blade block.

(35) FIG. 6 shows a side view of the stripping device 5 of FIG. 1 during or after the second method step. After clamping a region of the first section 12 of the cable 10 between the rollers 60, 62, the cable 10 is now moved along its longitudinal axis (the longitudinal axis runs from left to right or right to left in FIG. 6) in a first direction by means of a moving device 7 (e.g. a plurality of rollers as shown in FIG. 1), so that the second section 14 of the cable 10, in which the cable sheath 20 is present, is removed from the stripping blades 42, 44 or the rollers 60, 62. This movement is shown with an arrow in FIG. 6.

(36) The cable 10 is, so to speak, moved to the left in FIG. 6 while the rollers 60, 62 keep the inner conductors 30, 31 clamped or continue to press on the inner conductors 30, 31. This is a grazing relative movement. During the movement to the left in FIG. 6, the rollers 60, 62 rotate correspondingly around their respective axis of rotation.

(37) By pressing together or clamping the inner conductors 30, 31 between the rollers 60, 62 and simultaneously moving to the left in FIG. 6, the inner conductors 30, 31 approach an arrangement or alignment in which the inner conductors 30, 31 lie next to one another in one plane. When the inner conductors 30, 31 are twisted together, they are thereby (at least partially) untwisted.

(38) FIG. 7 shows a side view of the stripping device 5 of FIG. 1 during the third method step. After the cable 10 has been moved in the first direction, the pressure of rollers 60, 62 is increased on the first section 12 or a portion of the first section 12 of the cable 10. This is shown in FIG. 7 by two arrows. This increasing of the pressure of rollers 60, 62 on the portion of the first section 12 of the cable 10 is optional and does not need to be carried out.

(39) FIG. 8 shows a side view of the stripping device 5 of FIG. 1 during the fourth method step. Now, the cable 10 is moved in the second direction, which is opposite to the first direction. This means that the second section 14 of cable 10 is moved towards the stripping blades 42, 44 or the rollers 60, 62. This direction of movement of cable 10 is shown by an arrow in FIG. 8. In FIG. 8, the cable 10 is moved to the right. During this movement, the rollers 60, 62 rotate around their respective axis of rotation. This prevents kinking and/or bending of the inner conductors 30, 31 and/or the insulation 38. The rollers 60, 62 continue to keep the first section 12 of cable 10 clamped between the rollers 60, 62 or press in opposite directions on the first section 12 of cable 10.

(40) The second method step and the fourth method step (and, optionally, the third method step between the second method step and the fourth method step) can be alternately repeated, in particular repeated multiple times. This means that the cable 10 is moved alternately multiple times in the first direction and the second direction, while the cable 10 is or remains clamped between the rollers 60, 62. It is conceivable that the pressure of the rollers 60, 62 on the first section 12 is increased each time the direction of movement of cable 10 is reversed (from the first direction to the second direction and/or from the second direction to the first direction).

(41) Now, the inner conductors 30, 31 are next to each other in a row or a plane. This means, among other things, that the inner conductors 30, 31 are untwisted as far as they were twisted together.

(42) FIG. 9 shows a side view of the stripping device 5 of FIG. 1 during the fifth method step. FIG. 10 shows a perspective view of the stripping device 5 of FIG. 1 during the fifth method step.

(43) Finally, the cutter head 40 or the stripping blades 42, 44 are closed further than before, so that the stripping blades 42, 44 cut into the insulation 38 of the inner conductors 30, 31 at the top and bottom, respectively. This is indicated by the vertical arrows in FIG. 9.

(44) After the stripping blades 42, 44 have cut into the insulation 38, the cable 10 is moved in the first direction, i.e. to the left in FIG. 9. This way, the insulation 38 of the inner conductors 30, 31 is removed or pulled off the inner conductors 30, 31. The insulation 38 remains, so to speak, attached to the stripping blades 42, 44. The removal of the insulation 38 or the insulation of a plurality of inner conductors 30, 31, in particular all inner conductors 30, 31 of cable 10, is carried out simultaneously.

(45) As can be clearly seen in FIG. 10, the inner conductors 30, 31 lie next to each other in one plane when cutting into insulation 38 or when removing insulation 38.

(46) The pressure of rollers 60, 62 on the inner conductors 30, 31 of the cable 10 can be pneumatically adjusted or changed. This means that the pressure on the inner conductors 30, 31 of the cable 10 can be changed independently of the distance between the rollers 60, 62.

(47) The described movements of the cable 10 or the inner conductors 30, 31 are always to be understood as being relative to the blade block. This means that it is also possible that the cable 10 is not moved, but that the blade block is moved actively. However, important in each case is only the relative movement of the cable 10 with respect to the blade block or with respect to the stripping blades 42, 44 or the rollers 60, 62.

(48) Lateral movements of the rollers 60, 62 for aligning the inner conductors 30, 31 do not typically occur. The rollers 60, 62 are only moved towards each other to increase the pressure on the first section 12 of the cable 10, or moved away from each other to decrease the pressure on the first section 12 of the cable 10.

(49) The rollers 60, 62 are not moved relative to each other or in directions that are offset parallel to each other. The rollers 60, 62 are moved towards each other and thus the cable 10 is clamped or pressed between the rollers 60, 62. The rollers 60, 62 are not moved laterally relative to the cable 10 in order to actively untwist the inner conductors 30, 31. Therefore, it cannot happen that the rollers 60, 62 press or try to untwist the inner conductors 30, 31 in a direction that corresponds to the twisting direction of the inner conductors 30, 31, whereby the inner conductors 30, 31 are further twisted instead of being untwisted, which can lead to damage and/or deformation of the inner conductors 30, 31. By the movement of the rollers 60, 62 towards each other, the inner conductors 30, 31 are untwisted without damage or deformation of the inner conductors 30, 31, regardless of the twisting direction of the inner conductors 30, 31 and are arranged in one plane.

(50) The force acting from the stripping device 5 on the inner conductors 30, 31 acts on the inner conductors 30, 31 from above and below, so to speak, and in exactly opposite directions to each other. The rotatable rollers 60, 62 or rotatable cylinders press towards each other and thus ensure untwisting of the inner conductors 30, 31 and arrangement of the inner conductors 30, 31 in one plane.

(51) The plane runs between the two rollers 60, 62 and parallel to the axes of rotation of the rollers 60, 62. In the drawings, the plane in which the inner conductors 30, 31 are to be or will be arranged before the insulation of the inner conductors 30, 31 is cut and removed runs in each case horizontal.

(52) The stripping device 5 is also referred to as cut & strip device.

(53) Finally, it should be noted that terms such as “having”, “comprising”, etc. do not exclude other elements or steps and terms such as “a” or “an” do not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps of other exemplary embodiments described above.

(54) In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

REFERENCE LIST

(55) 5 Stripping device 7 Moving device 10 Cables 12 First section 14 Second section 20 Cable sheath 30 Inner conductor 31 Inner conductor 35 Strands 36 Strands 38 Insulation 40 Cutter head 42 Stripping blade 44 Stripping blade 46 Cutting blade 48 Cutting blade 50 Compression spring 52 Compression spring 60 First roller 62 Second roller 64 Pneumatic actuator