Producing a removal aid in a foil of a foiled metal sheet

Abstract

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for producing a foil slitting cut in a foil of a foiled metal sheet. A foil slitting tool is moved along a predetermined path with a tool tip resting on the metal sheet and thereby mechanically produces the foil slitting cut by displacing foil material along the path. The foil slitting cut has at least one acute-angled tooth for forming at least one foil corner detached from the metal sheet.

Claims

1. A method of producing a foil slitting cut in a foil of a foiled metal sheet, the method comprising: placing a tool tip of a foil slitting tool on the foiled metal sheet; moving the foil slitting tool to produce a closed slitting gap in the foiled metal sheet to form a foil segment cut for a foil segment to be removed; and additionally moving the foil slitting tool along a predetermined path with the tool tip resting on the foiled metal sheet to mechanically produce an additional foil slitting cut in the foil segment cut, the additional foil slitting cut having at least one acute-angled tooth with foil material displaced along the path to form at least one foil corner that is automatically detached away from the foiled metal sheet and projects upwards, removing the foil segment by initially grasping the detached foil corner, the detached foil corner remaining connected with the foil segment.

2. The method of claim 1, wherein the tool tip comprises a rotatably mounted ball, and wherein moving the foil slitting tool comprises rolling the rotatably mounted ball on the foiled metal sheet.

3. The method of claim 1, wherein the tool tip comprises a needle tip of a pointed needle.

4. The method of claim 1, wherein mechanically producing the additional foil slitting cut comprises slitting the foiled metal sheet at an acute angle without lifting the foil slitting tool from the foiled metal sheet, such that the foil material curls up at a tip of the at least one acute-angled tooth to thereby form the at least one foil corner detached away from the foiled metal.

5. The method of claim 1, wherein the additional foil slitting cut has a plurality of acute-angled teeth oriented in a common direction and joined to one another by curved slitting cut portions.

6. The method of claim 1, wherein the additional foil slitting cut has at least one zigzag portion with a plurality of acute-angled teeth arranged next to one another and oriented in opposite directions and forming two rows of teeth.

7. The method of claim 6, wherein the teeth of the at least one zigzag portion are arranged such that a continuous slitting gap is formed between the detached foil corners of the two rows of teeth oriented in opposite directions, the slitting gap being wider than the additional foil slitting cut.

8. The method of claim 1, wherein the additional foil slitting cut extends to an outside edge of the foil or to an edge of the foil segment cut in the foil.

9. The method of claim 8, wherein the additional foil slitting cut merges into the outside edge or segment edge asymptotically or at an acute angle.

10. The method of claim 1, wherein the additional foil slitting cut is spaced from any existing edges of the foil as produced.

11. The method of claim 1, wherein mechanically producing the additional foil slitting cut comprises forming the additional foil slitting cut by a single continuous cut without lifting the foil slitting tool from the foiled metal sheet.

12. The method of claim 1, wherein mechanically producing the additional foil slitting cut comprises making a first non-continuous cut and then making a second non-continuous cut either beginning in a cutting gap produced by the first non-continuous cut or running at least partially therein.

13. The method of claim 1, wherein the additional foil slitting cut extends to the closed slitting gap on a segment edge of the foil segment and merges into the segment edge at an acute angle of less than 90 degrees.

14. The method of claim 1, wherein the predetermined path is configured such that the foil material automatically curls up at a reversal point of a direction of the moving to form the at least one foil corner that has a corresponding acute-angle and is detached from the foiled metal sheet.

15. The method of claim 1, wherein the predetermined path is a single path of the additional foil slitting tool, and the at least one acute-angled tooth in the foil slitting cut is produced by the tool tip resting on the foiled metal sheet and moving along the single predetermined path.

16. A method of removing a foil segment of a foiled metal sheet, the method comprising: placing a tool tip of a foil slitting tool on the foiled metal sheet; moving the foil slitting tool to produce a closed slitting gap in the foiled metal sheet to form a foil segment cut for a foil segment to be removed; additionally moving the foil slitting tool along a predetermined path to mechanically produce an additional single foil slitting cut in the foil segment with the tool tip resting on the foiled metal sheet, wherein the predetermined path is configured such that the additional single foil slitting cut is produced to have at least one acute-angled tooth to result in at least one foil corner that is detached from the foiled metal sheet to curl up; then removing the foil segment by initially grasping the at least one detached foil corner as a removal aid, the at least one detached foil corner remaining connected with the foil segment.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows a foiled metal sheet having a plurality of foil segments separated from one another, each having different foil slitting cuts according to the invention for forming a foil corner detached from the metal sheet.

(2) FIG. 2 shows a longitudinal section of a known foil slitting tool for producing the foil slitting cuts shown in FIG. 1.

(3) FIG. 3 shows a longitudinal section of a further known foil slitting tool for producing the foil slitting cuts shown in FIG. 1.

(4) FIG. 4 shows a metal-sheet processing machine for carrying out the method according to the invention.

(5) FIG. 5 shows a further foiled metal sheet having a plurality of foil segments separated from one another, each having further foil slitting cuts according to the invention for forming a foil corner detached from the metal sheet.

(6) In the following description of the drawing, identical reference numerals are used for components which are the same or have the same function.

DETAILED DESCRIPTION

(7) FIG. 2 shows a known foil slitting tool 20 for foiled metal sheets 1, that is to say, for metal sheets 2 which are provided with a foil 3 to protect them against damage. The foil slitting tool 20 serves to produce a foil slitting cut 24 in the foil 3 of the foiled metal sheet 1 without leaving scratches or marks on the metal sheet 2.

(8) The foil slitting tool 20 has a blunt tool tip in the form of a ball 22 which is rotatably mounted in a die 21 and which is moved on the foiled metal sheet 1 with a rolling movement and thereby cuts the foil 3. More precisely, the ball 22 pierces the foil 3 and, when the foil slitting tool 20 is moved over the foiled metal sheet 1 in direction A, rolls on the metal sheet 2 and thereby produces the foil slitting cut 24 mechanically by displacing foil material along the path that is travelled.

(9) FIG. 3 shows a further known foil slitting tool (foil marking tool) in the form of a pointed needle 30. The needle 30 is moved on the foiled metal sheet 1 and thereby cuts the foil 3. More precisely, the needle tip 31 pierces the foil 3 and, when the needle 30 is moved over the foiled metal sheet 2 in direction A, produces the foil slitting cut 32 mechanically by displacing foil material along the path that is travelled. If the needle tip 31 is made of a softer material than the metal sheet, for example of brass, there are no scratches on the metal sheet 2. If scratches on the metal sheet 2 are not important, a needle tip 31 made of a harder material than the metal sheet can also be used.

(10) FIG. 1 shows a foiled metal sheet 1 in the foil 3 of which six square foil segments 5a-5f have been cut in each case by means of a closed slitting gap 6. If welding work, for example, is to be carried out on the metal sheet 1 at specific processing locations, the foil segment in question only has to be removed manually from those processing locations. However, in the case of a ball diameter of less than 1 mm, the slitting gap 6 produced with the foil slitting tool 20 is very narrow (less than 0.5 mm) and consequently does not facilitate the manual detachment of a foil segment.

(11) Therefore, each of the foil segments 5a-5f has, as a removal aid, at least one foil corner 7a-7f which is detached from the metal sheet 2 and can be gripped by hand. These detached foil corners 7a-7f are formed in the respective foil segments 5a-5f as follows: in each of the foil segments 5a-5f there is formed, by means of the foil slitting tool 20, an additional foil slitting cut 8a-8f which has at least one acute-angled tooth 9a-9f. When the foil 3 is slit at an acute angle of less than 90 degrees, preferably of less than 45 degrees without lifting the foil slitting tool 20, the foil 3 curls up at the reversal point of the processing direction, that is to say, at the tip of the tooth. The associated acute-angled foil corner 7a-7f is thereby detached from the metal sheet 2 and projects upwards as a removal aid.

(12) In foil segments 5a-5c, 5e, 5f, the foil slitting cut 8a-8c, 8e, 8f extends to the slitting gap 6, that is to say, to the segment edge of the foil segment 5a, only on one side and merges into the segment edge at an acute angle of less than 90 degrees, in order to prevent the foil or foil segment from tearing uncontrollably when it is removed. Alternatively, the foil slitting cut can also extend to the segment edge of the foil segment on both sides.

(13) In foil segment 5a, the foil slitting cut 8a has three acute-angled teeth 9a which are oriented in the same direction and are joined to one another by curved slitting cut portions 10. In total, therefore, there are three detached foil corners 7a.

(14) In foil segment 5b, the foil slitting cut 8b has two acute-angled teeth 9b which are oriented in opposite directions and are joined to one another by an S-shaped slitting cut portion 11. In total, therefore, there are two detached foil corners 7b.

(15) In foil segment 5c, the foil slitting cut 8c has a zigzag portion 12 with a plurality of acute-angled teeth 9c which are arranged next to one another and are oriented alternately in opposite directions, as a result of which a plurality of detached foil corners 7c are formed. Generally, the more acute-angled the teeth, the easier they are to detach.

(16) In foil segment 5d, the foil slitting cut 8b has a single acute-angled tooth 9d between two S-shaped curve portions 11. The foil slitting cut 8d is at a distance from the segment edge on both sides, that is to say, it is formed wholly within the foil segment 5d.

(17) In foil segment 5e, the foil slitting cut 8e has a zigzag portion 12, the teeth 9e of which are so acute-angled and are arranged so shortly and closely together that there is a continuous slitting gap 14 between the detached foil corners 7e of the two rows of teeth 13a, 13b oriented in opposite directions, which slitting gap 14 is wider than the foil slitting cut 8e of the foil slitting tool 20. The foil corners 7e detached on both sides of the slitting gap 14 each form a foil edge which can be used as a removal aid.

(18) In foil segment 5f there are formed two foil slitting cuts 8f which are separate from one another and each of which has an acute-angled tooth 9f and an S-shaped slitting cut portion 11 extending to the segment edge. In total, therefore, there are two detached foil corners 7f.

(19) FIG. 4 shows a numerically controlled metal-sheet processing machine 40 with which the above-described slitting cuts with acute-angled teeth can be formed in a foiled metal sheet 1. This metal-sheet processing machine 40 comprises a workpiece support 41 for holding a foiled metal sheet 1, a workpiece movement system 42 for moving the foiled metal sheet 1 located on the workpiece support 41 in the x- and y-direction, a tool receptacle 43 which is movable in the z-direction and receives the foil slitting tool 20, 30, and an NC machine control system 44 (not shown in detail) which is programmed by means of an NC program and which controls actuators of the workpiece movement system 42 and the tool receptacle 43 in order to execute the above-described slitting cuts with acute-angled points in the foiled metal sheet 1.

(20) FIG. 5 shows a further foiled metal sheet 1 in the foil 3 of which four square foil segments 5g-5j have been cut in each case by means of a closed slitting gap 6. Each of the foil segments 5g-5j has, as removal aid, at least one foil corner 7g-7j which is detached from the metal sheet 2 and can be gripped by hand. In order to form these detached foil corners 7g-7j there is formed in each of the foil segments 5g-5j, by means of the foil slitting tool 20, an additional foil slitting cut 8g-8j which has an acute-angled tooth 9g-9j with an acute angle of less than 90 degrees, preferably of less than 45 degrees. The foil 3 curls up at the tip of the tooth. The associated acute-angled foil corner 7g-7j is thereby detached from the metal sheet 2 and projects upwards as a removal aid.

(21) In foil segment 5g, the foil slitting cut 8g has an acute-angled tooth 9g, which are formed by two mutually facing curved slitting cut portions 8g.sub.1, 8g.sub.2 which extend acutely or asymptotically relative to one another and meet at the tip of the tooth. The two slitting cut portions 8g.sub.1, 8g.sub.2 can be cut as a continuous cut, that is to say without lifting the foil slitting tool 20, whereby the foil 3 curls up at the reversal point of the processing direction, that is to say at the tip of the tooth, and the acute-angled foil corner 7g is thereby detached from the metal sheet 2 and projects upwards as a removal aid. The two slitting cut portions 8g.sub.1, 8g.sub.2 can also be two non-continuous cuts, and the cut made last (e.g., the slitting cut portion 8g.sub.2) begins in the cutting gap of the slitting cut portion 8g.sub.1 made first and extends away from the tip of the tooth in the cutting direction 15.

(22) In foil segment 5h, the foil slitting cut 8h has an acute-angled tooth 9h which is formed by two mutually facing curved slitting cut portions 8h.sub.1, 8h.sub.2, which touch at a cutting point and each extend further on both sides of this cutting point. The two slitting cut portions 8h.sub.1, 8h.sub.2 are two non-continuous cuts, and the cut made last (e.g. the slitting cut portion 8h.sub.2) comes from the cutting direction 15, that is to say from the side of the cutting point remote from the foil corner 7h to be detached, and runs partially in the cutting gap of the slitting cut portion 8h.sub.1 made first.

(23) The foil slitting cut 8i of foil segment 5i differs from the foil slitting cut 8g only in that only one slitting cut portion 8i.sub.2 is curved and the other slitting cut portion 8i.sub.1 is straight.

(24) The foil slitting cut 8j of foil segment 5j differs from the foil slitting cut 8i only in that the straight slitting cut portion is here formed by the slitting gap 6 and the curved slitting cut 8j begins in the slitting gap 6 and is then formed in direction 15 in order to detach the foil corner 7j.

(25) Tests with the foil slitting tool 20 (cut width 1 mm) have shown that the method according to the invention for forming detached foil corners 7a-7j works at any movement speed possible with the metal-sheet processing machine 40 used (maximum movement speed: 60 m/min).

(26) A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.