Note: Descriptions are shown in the official language in which they were submitted.
CA 02771914 2012-02-23
PROFILED ELEMENT AND METHOD FOR PRODUCING A PROFILED
ELEMENT
The present invention relates to a section element, in particular to a
structural section, for example a dry construction section, a facade
section, a plaster section, a screed section or a tile section, having an
elongated base body, in particular comprising metal or plastic, in which at
least one opening is formed. The invention is furthermore directed to a
method of manufacturing such a section element.
Section elements of this kind are known, for example, from WO
2004/055289 Al and can in particular be used as C-shaped upright
sections for dry construction. The elongated base body is provided with a
predefined cutting pattern, for example, for manufacturing the section
elements. On the selection of suitable cutting patterns, two longitudinal
portions of the section element which extend in parallel can in particular
be drawn apart in a folding process, whereby a widening of the section
element takes place without additional material input. The drawn apart
longitudinal sections are in this respect connected to one another via
connection elements formed integrally with the longitudinal portions.
Corresponding cutting patterns are described in WO 2004/055289 Al
whose content, in particular relating to the cutting patterns described in
this document, is herewith explicitly included in the disclosure content of
the present application.
A further possibility of producing widened section elements is described in
WO 2007/ 101594 Al. In this document, a section element is inter alia
described which is not produced by a folding process, but rather by a
purely widening process, in which slits introduced into the section are
widened by drawing up to diamond-shaped openings. Such a section
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2
element can also in particular be used for manufacturing upright sections.
The content of this document, in particular relating to the cutting patterns
described in this document, is also herewith explicitly included in the
disclosure content of the present application.
Corresponding section elements can furthermore also be manufactured
without a widening procedure or folding procedure so that the base body,
as is, for example, usual with normal upright sections, has a non-
elongated, substantially closed design. Openings of the initially named
kind can be introduced into such a base body, for example by a punching
process. It is disadvantageous in this that the punched out material forms
waste, whereby the manufacturing costs for such section elements are
increased.
It is generally often desirable with section elements of the initially named
kind, and in particular with upright sections, that leadthrough openings
are provided through which, for example, cables, lines or other elongated
band-like or cord-like elements as well as pipes or other hollow bodies can
be led. Independently of whether such leadthrough openings are produced
by punching out corresponding holes in the base body, by the described
folding process or by drawing apart, there is the problem that the section
element has a reduced stiffness in the region of the produced opening, in
particular in a direction transverse to the longitudinal extent of the section
element.
DE 10 2007 053 471 Al discloses a section element having an elongated
base body in which at least one opening is formed which includes at least
one edge which is formed transversely to the longitudinal extent of the
base body and which is covered by a cover element.
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FR 2 712 831 Al discloses a section element having a plurality of
openings and a bent over flange edge surrounding the openings.
US 2003/0221384 Al discloses a wall panel for a room divider having
clips which are clipped to panel elements of the wall panel.
It is an object of the present invention to provide a section element of the
initially named kind in which the stiffness in the region of the opening is
increased with respect to conventional section elements.
Starting from a section element of the initially named kind, this object is
satisfied in accordance with the invention in that the opening includes at
least one edge which is formed transversely to the longitudinal extent of
the base body and which is formed at least partly by a bent over portion of
the base body; in that the bent-over portion forms an at least double-layer
region of the base body together with an adjacent portion of the base body
made in one piece with the bent over portion; and in that the bent-over
portion is connected to the adjacent portion within the at least double-
layer region to increase the stiffness of the section element transversely to
its longitudinal extent.
A method designed in accordance with the invention of manufacturing
such a section element has the features that slits are introduced into the
base body for folding out a portion of the base body; in that the portion is
folded out and bent over for forming an opening in the base body, along a
kink line extending transversely to the longitudinal extent of the base
body and connecting the slits, until the bent over portion forms an at least
double-layer region of the base body together with an adjacent portion of
the base body made in one piece with the bent over portion; and in that
the bent over portion is connected to the adjacent portion within the at
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least double-layer region to increase the stiffness of the section element
transversely to its longitudinal extent.
In accordance with the invention, the reduced stiffness caused by the
opening is compensated in that an at least double-layer region is produced
directly in the region of an edge of the opening extending transversely to
the longitudinal direction of the section element and the individual layers
of this region are connected to one another so that no displacement of the
two layers toward one another is possible. At least one of the layers is
produced by a material portion which forms at least one region of the
opening by folding out of the base body. It is thereby achieved, on the one
hand, that the material used for forming the opening is not wasted, but is
rather used for stiffening the base body. On the other hand, it is
automatically ensured by folding out the portion from the opening that the
stiffening effect is present directly in the region of the opening, i.e. in
the
region of the weak point produced by the opening. In this respect, the
term "transverse" is to be understood as any direction which does not
extend only in the longitudinal direction of the section element. The
transversely extending edge can in particular be formed as a straight line
or curved as long as it extends transversely to the longitudinal direction of
the section element at least in a part region.
Furthermore, no supply of a separate part to increase the stiffness is
required due to the integral connection of the portion folded out of the
base body. The manufacture of the stiffening region is possible in an
online process, even at very high speeds such as much higher than 100
m/min, due to the integral connection of the bent over portion to the base
body.
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In accordance with an advantageous embodiment of the invention, the
edge extends at least regionally substantially perpendicular to the
longitudinal extent of the base body. A uniform support edge for lines to
be led through the opening or the like is thereby provided. At the same
5 time, the double layered region also extends perpendicular to the
longitudinal extent of the base body so that the increased stiffness is also
achieved in an ideal fashion in a direction perpendicular to the
longitudinal extent of the base body.
In accordance with a further preferred embodiment of the invention, the
bent over portion is connected to the adjacent portion by a pressure
joining process such as clinching or crimping, by clamping, squeezing,
pressing, welding, screwing, bonding or riveting. The firmer the connection
between the bent over portion and the adjacent portion of the base body,
the greater the stiffness of the section. In particular a shear movement
between the layers of the multilayer region should be prevented using the
selected connection process so that, for example, an arching of the section
element is prevented.
The edge is advantageously formed over its total length by the bent over
portion. This can be the case, for example, when the base body is not
divided into two spaced apart longitudinal portions by drawing apart or by
the initially described folding process, but rather substantially forms a
closed surface. In this case, after introduction of corresponding slits into
the base body, a portion defined by these slits can be bent out of the base
body, wherein the edge arising on the bending over of this portion
automatically extends over the total length of the opening thereby arising.
Since the edge is in this case formed as a kink edge over its total length, it
is ensured that the edge is not formed as a sharp edge, but rather has a
certain roundness. It is thereby achieved that lines led through the
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opening can lie on the edge without there being any risk of damage to the
lines.
In accordance with a further advantageous embodiment of the invention, a
first part of the edge is formed by the bent over portion. A second part of
the edge, which is formed by a non-bent over portion of the base body,
advantageously adjoins the first part of the edge. In this respect, the non-
bent over portion can in particular form at least a part of the adjacent
portion of the base body. The first part of the edge can preferably be
formed by a single-layer bent over portion which is adjoined by at least
one second part of the edge which is formed by a double-layer bent over
portion of the base body.
This design is in particular sensible when the base body is divided into
two longitudinal portions which are drawn apart by the initially described
folding process. The openings already arising due to the folding process
can additionally be enlarged by correspondingly bent over portions,
whereby parts of the edge merging into one another are formed both by
the bent over portions of the first longitudinal portion of the base body, for
example, and by non-bent over portions of the second longitudinal
portion. The bent over portion can in this case form a double-layer region
both with the first longitudinal portion and with the second longitudinal
portion, wherein the connection of the bent over portion to the respective
adjacent portions can be established both in one of these double-layer
regions and in both double-layer regions to achieve an increased stiffness.
In this embodiment, the base body advantageously includes two mutually
spaced apart longitudinal portions which extend parallel to one another
and are connected to one another at a plurality of connection points via
connection elements formed in one piece with the longitudinal portions
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and in each case bridging the spacing between the longitudinal portions,
wherein the opening extends from one of the longitudinal portions beyond
the spacing to the other longitudinal portion and the bent over portion
forms a region of the edge bridging the spacing between the longitudinal
portions.
In accordance with a further advantageous embodiment of the invention,
the opening includes at least two correspondingly formed edges in
particular disposed opposite one another. The desired improved stiffness
is thereby achieved at both oppositely disposed sides of the opening and
thus an even higher stiffness of the section element in the region of the
opening overall.
In accordance with a further preferred embodiment of the invention, the
section element is formed as a C section, a U section, an L section, a T
section, H sections, a hat section or a Z section. The section element in
accordance with the invention can generally also be used for other
suitable section types.
In accordance with a further advantageous embodiment of the invention,
the edge is at least regionally engaged over and in particular encompassed
by a cover element. This is in particular sensible with a sharp-edged
design of the edge since in this case lines led through the opening do not
lie on the edge formed with a sharp edge, but rather on the cover element
engaging around it. It is thereby ensured that no damage can occur to the
elements led through the opening. The cover elements can in this respect
not only engage around the support edge, but advantageously also be
formed so that the total peripheral edge of the opening is engaged over and
in particular encompassed.
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The edge can advantageously be provided at least regionally with a bend,
in particular a flange. This can in particular take place as an alternative;
generally, also however, in addition to the described cover element. It is
also achieved by a bend that the support for lines led through the opening
is made rounded despite any formation of the edge as a sharp edge.
Damage to the elements led through the opening is thereby in turn
avoided.
Whereas the opening can, as already described, advantageously be formed
as a leadthrough opening, in particular for electrical lines, it is generally
also possible that the opening satisfies a function different from this. The
opening can in particular, for example, also be used as an air passage
opening or as a passage opening for other materials such as insulating
materials. A stiffening of the section element is also achieved by the design
in accordance with the invention in this case.
A plurality of openings are advantageously provided which are in
particular arranged distributed in the longitudinal direction of the base
body. The openings can in this respect in particular be present at regular
intervals. The flexible use of a section element designed In accordance
with the invention for the leading through of lines, cables or the like is
further increased by the arrangement of a plurality of openings.
Further advantageous embodiments of the invention are set forth in the
dependent claims.
The invention will be described in more detail in the following with
reference to embodiments and to the drawings; there are shown in these:
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Fig. 1 a detail of a strip-like material portion with cutting
patterns for producing a section element formed in
accordance with the invention;
Fig. 2 a C section made in accordance with the invention,
Fig. 3 a detail of a further strip-like material portion with a
modified cutting pattern;
Fig. 4 the metal element in accordance with Fig. 3 after the
expansion;
Fig. 5 a further C section in accordance with the invention
formed with the cutting pattern in accordance with Fig.
3;
Fig. 6 a perspective representation of a cover element;
Figs. 7 to 9 perspective representations of further cover elements;
and
Figs. 10 to 13 four different states during the manufacture of a further
embodiment of the invention.
Fig. 1 shows an elongated, flat material portion 1, which can comprise, for
example, metal, plastic or other suitable materials for manufacturing a
section element in accordance with the invention. The material portion 1
includes an elongated base body 2 which includes a base portion 3
extending in the longitudinal direction as well as two portions 4 which are
laterally adjacent to the base portion 3 and which can be bent over by 90
CA 02771914 2012-02-23
in each case along a dashed line 6 for producing limbs 5 (Fig. 2) so that an
upright section 7 shown in Fig. 2 is produced. In this respect, outwardly
disposed marginal regions 8 of the portions 4 can again be angled by 90
with respect to the limbs 5 to produce a C-shaped upright section 7 in this
5 manner.
A plurality of slits 9, 10 are formed in the base portion 3 of which the slits
9 extend in the longitudinal direction of the base body 2 and the slits 10
extend perpendicular thereto. The slits 9, 10 can in this respect be
10 produced, for example, by rotary stamping, laser cutting or another
suitable cutting or stamping process.
Two respective slits 9 are connected by kink lines 11 which are shown as
dashed lines and along which portions 12 of the base body 2 can be bent
over for forming openings 13 (Fig. 2). Edges 14 of the openings 13 are
respectively produced by the bent over portions 12 in accordance with Fig.
2 and extend transversely, and in particular perpendicular, to the
longitudinal extent of the base body 2. The bent over portions 12 of the
base body 2 are in this respect bent over so much in accordance with Fig.
2 that they come into areal contract at adjacent portions 15 of the base
body 2 which are shown as hatched areas in Fig. 1. Together with the
adjacent portions 15, the bent over portions 12 thus form double-layer
regions 16 of the base body 2 which are disposed, viewed in each case in
the longitudinal direction of the base body 2, respectively directly
adjoining the openings 13.
As can further be recognized from Fig. 2, connection means 17 are
provided which are, for example, formed as rivets, and with which the
bent over portions 12 are fixedly connected to the adjacent portions 15.
Relative movements between the bent over portions 12 and the adjacent
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portions 15 are prevented by the connection means 17, whereby a
stiffening of the base body 2 is achieved directly in the region of the
openings 13, i.e. in the region weakened in its stiffness by the openings
13. It can, for example, be achieved by this stiffening effect that, on the
use as an upright section, a bending of the base portion 3 on a lateral load
of the limbs 5, such as can occur on the screwing in of screws on the
attachment of planking, is avoided.
The openings 13 can be used for leading through elements such as
electrical lines 18. Since the edges 14 are each formed by the bent over
portions 12, the edges 14 are not made as sharp edges, but rather have a
certain rounding. It is thereby avoided that damage takes place to the
insulation of the electrical lines 18 which lie on the edges 14.
Fig. 3 shows a material portion 19 with a base body 35 which has a
plurality of slits 20 which extend obliquely and along the longitudinal
extent of the material portion 19. Corresponding cutting patterns and
modified cutting patterns are described in WO 2004/055289 Al whose
disclosure content relating to the different possible cutting patterns and
their use for expanding material portions is explicitly included in the
present application.
In addition to the slits forming these known cutting patterns, slits 22 are
formed in Fig. 3 which adjoin two slits 21 extending obliquely and which
extend transversely to the longitudinal extent of the material portion 19. A
slit 23 extending in the longitudinal direction of the material portion 19
adjoins each of the slits 22 and is in turn adjoined by a further slit 24
extending parallel to the respective slit 22. The ends of the two slits 24 are
in turn connected to one another by a slit 25 extending in the longitudinal
direction.
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Starting approximately form the center of the slit 25, a further slit 26 in
turn extends parallel to the slits 24 and beyond their ends, with in turn
two slits 27, 28 adjoining the end of the slit 26 which extend in the
longitudinal direction and which each end approximately at the level of
the slits 24. The ends of the slits 27, 28 are connected to the slits 24 in
each case via dashed lines 29,30 which represent kink lines 31, 32 such
as will be set forth in the following.
Portions 33, 34, of the base body 35 which can be bent over along the
kink lines 31, 32, as will be explained in more detail in the following, are
bounded by the slits 24, 25, 26, 27 and 28. Respective slit-shaped
openings 36 are formed in the portions 33, 34 and extend in the
longitudinal direction of the material portion 19.
Tongue-like portions 37, 38 of the base body 35 at whose ends tabs 39, 40
are formed are furthermore formed by the slits 22, 23 and 24.
The base body 35 of the material portion 19 is divided into two
longitudinal portions 41, 42 by the slits 20 to 28, said longitudinal
portions being able to be drawn apart transversely to the longitudinal
extent of the material portion 19 in accordance with Fig. 4 and being
connected to one another in the drawn apart state via connection
elements 43 formed in one piece with the longitudinal portions 41, 42 and
respectively bridging the spacing between the longitudinal portions 41, 42.
It can be recognized from Fig. 4 that an opening 44 which is bounded by
edges 45, 46 in the longitudinal direction of the material portion 19 is
created between the longitudinal portions 41, 42 by the drawing apart and
by an additional bending over of the portions 33, 34 along the kink lines
29, 30.
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A first part 47 of the edges 45, 46 is in this respect in each case formed by
the bent over portions 33, 34, whereas a second part 48 of the edges 45,
46 adjoining it is formed by the non-bent over tongue-like portions 37, 38.
The bent over portions 33, 34 in this respect contact, in a similar manner
to that described in Figs. 1 and 2, adjacent portions 49, 50 of the base
body 35 which are in turn shown as hatched regions in Fig. 3. Further
adjacent portions 51, 52 are formed by the ends of the tongue-like
portions 37, 38 which, after the bending over of the portions 33, 34, as
also the adjacent portions 49,. 50, form double-layer regions 53, 54 of the
base body 35 together with the bent over portions 33, 34.
The bent over portions 33, 34 are respectively fixedly connected to the
adjacent portions 49 to 52 via connection means 55, 56 within the double-
layer regions 53, 54. The connection means 55 are in this respect shown
by way of example as rivet connections, but can also be formed as other
suitable connection means already initially described. The connection
means 56 are formed by way of example in Fig. 4 by the slit-shaped
openings 36 and by the tabs 39, 40 of the tongue-like portions 37, 38. For
this purpose, the tabs 39, 40 are bent over and pushed through the slit-
shaped openings 36, as can be recognized from Fig. 4.
Fig. 5 shows a C-shaped upright section 57 which is manufactured from a
material portion 35 in accordance with Figs. 3 and 4. The upright section
57 includes a plurality of openings 44 through which respective electrical
lines 18 or other supply lines can be led. Since the edges 45 of the
openings 44 on which the electrical lines 18 lie are only formed as a
rounded edge by bending over the portion 34 in their regions 58 shown at
the right in Fig. 5, there is a risk that the electrical lines 18 led through
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will be damaged without additional protective measures if they lie on the
other region of the edge 45.
To avoid such damage, in accordance with the representation of the upper
opening 44 in Fig. 5, the remaining region of the edge 45 can be provided
with a bend 63, for example with a flange.
Additionally or alternatively, in accordance with the middle representation
in Fig. 5, the edge 45 can be provided with a cover element 59. The cover
element 59 can, for example, have the shape of a sleeve with a
longitudinal slit shown in Fig. 6. The cover element 59 can in this case be
simply plugged onto the edge 45 and can either be held by a
corresponding clamping effect or can additionally be squeezed or pressed.
Since the upper side of the cover element 59 is made rounded, damage to
the electrical line 18 is prevented in this manner.
The cover element can have different shapes and can, for example, also be
made as a hook-shaped cover element 60 in accordance with Figs. 7 to 9.
In this respect, an additional fastening of the cover element 60 to the base
body 35 is possible by an extended downwardly projecting portion 61 of
the cover element 60, for example by riveting or by another of the initially
described kinds of connection.
As shown in the lower region in Fig. 5, the opening 44 can also be covered
over its total periphery by a corresponding cover element 62. The cover
element 62 thus forms an eyelet which is closed all round and which
covers the edge 45 as well as the edges of the opening 44 adjoining it in a
similar manner to the cover elements 59 and 60 respectively.
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In contrast to the rectangular shape shown in Fig. 5, the cover element or
the eyelet can also have rounded regions so that ultimately a
correspondingly rounded inner contour of the opening is achieved. In this
manner, a circular, an elliptical, an oval or also an angular shape with
5 rounded corners can be achieved, for example. In this respect, the
openings themselves can already have a corresponding rounded shape. It
is, however, also possible that the openings have an angular shape such
as is shown by way of example in Fig. 5 and a rounded inner contour only
arises by correspondingly formed cover element or eyelets which e.g. have
10 a larger radial thickness at the corners than in the portions lying between
the corners.
Fig. 10 shows a further embodiment of the invention in which the cutting
pattern in accordance with Fig. 3 is modified. For simplification, only the
15 differences from the embodiment in accordance with Figs. 3 to 5 will be
described in more detail in the following. The same or similar elements are
in this respect provided with the same reference numerals in Figs. 10 to
13 as in Figs. 3 to 5.
In Fig. 10, slits 64 adjoin the slits 21 and respectively extend transversely
to the longitudinal extent of the material portion 19 and respectively
extend only up to the center line 65 of the material portion 19 or up to the
level of the center of the cutting patterns formed by the obliquely
extending slits 20, 21 in the upper and lower regions of the material
portion 19. In this respect, one of the slits 64 extends starting from a slit
21 ending at one side of the middle line 65 and the other slit 64 extends
starting from a slit 21 ending on the other side of the center line 65 in the
direction toward the center line 65.
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A respective slit 66 which runs along the center line 65 and which is in
turn adjoined by a further slit 67 extending oppositely and parallel to the
respective slit 64 adjoins the slits 64. A respective slit 68 extending
perpendicular to the respective slit 67 is formed at the ends of the slits 67
and thus extend parallel to one another and parallel to the longitudinal
extent of the material portion 19. The centers of the two slits 68 are
connected to one another via a slit 69 extending parallel to the slits 67.
The slits 68 furthermore each extend beyond the slits 67 and end in
obliquely extending slits 70 which are connected to one another via kink
lines 71 shown in dashed lines. In a similar manner, the ends of the slits
67 are connected to the slits 68 via kink lines 72 shown in dashed lines.
Corresponding to the obliquely extending slits 70, respective slits 73
which extend obliquely and through which triangular holes 74 are created
between the slits 68, 68 and 73 are formed between the slits 68 and 69, as
can be recognized in Fig. 10. Both the obliquely extending slits 70 and the
obliquely extending slits 73 are only provided optionally and prevent
corners with sharp edges from arising at the resulting section element.
These slits can therefore also generally also be omitted. To avoid corners
with sharp edges, the slits 70, 73 could also be replaced by curved slits,
for example, so that ultimately rounded corners are created.
First portions 75 which are adjoined by second portions 76 bordered
between the kink lines 71 and 72 and the slits 68 and 70 are formed
between the slits 68 and 69 and the kink lines 72. Furthermore, third
portions 77 are formed between the slits 66, 67, 68 and 70 and the kink
lines 71.
After introduction of the cutting pattern shown in Fig. 10, as already
described analogously with respect to Fig. 4, the two longitudinal portions
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41, 42 of the base body 35 are drawn apart. A spacing thereby arises
between the longitudinal portions 41, 42 which is bridged by the
connection elements 43, as is shown in Fig. 11.
The portions 74 are subsequently each bent over along the kink lines 72,
whereby an opening 78 shown in Fig. 12 is produced.
In a further step, the portions 75 already bent over once are bent over a
second time together with the portions 76 and 77 now to be bent over for
the first time along the kink lines 71 so that the opening 78 receives its
final size as is shown in Fig. 13. The bent over portions 75, 76, 77 form,
together with adjacent portions 79, 80 (see Fig. 10) of the base body 35,
double-layer or triple-layer regions 81, 82, 83, within which the bent over
portions 75, 76, 77 are connected to the adjacent portions 79, 80 by
connection means 84. The connection means 84 can in this respect again
be formed in a variety of manners such as was already described in detail
within the framework of this application.
In this embodiment, not only one part, but two respective parts 85, 86 of
the edges 87, 88 bounding the opening 78 in the longitudinal direction of
the material portion are formed directly by kink edges created along the
kink lines 71 on the bending over of the portions 76, 77 so that these
parts 85, 86 are formed as rounded edges. Additional cover elements or
eyelets for the edges 87, 88 are therefore not absolutely necessary.
Generally, however, the already described cover elements and eyelets can
also additionally be used in this embodiment.
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Reference numeral list
1 material portion
2 base body
3 base portion
4 portions
5 limbs
6 dashed lines
7 upright section
8 marginal regions
9 slits
10 slits
11 kink lines
12 bent over portions
13 openings
14 edges
15 adjacent portions
16 double-layer regions
17 connection means
18 electrical lines
19 material portion
20 slits
21 slits
23 slits
24 slits
25 slit
26 slit
27 slit
28 slit
29 dashed line
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30 dashed line
31 kink line
32 kink line
33 bent over portions
34 bent over portions
35 base body
36 slit-shaped opening
37 tongue-like portion
38 tongue-like portion
39 tab
40 tab
41 longitudinal portion
42 longitudinal portion
43 connection elements
44 openings
45 edges
46 edges
47 first part of the edge
48 second part of the edge
49 adjacent portions
50 adjacent portions
51 adjacent portions
52 adjacent portions
53 double-layer regions
54 double-layer regions
55 connection means
56 connection means
57 upright section
58 region of the edge
59 cover element
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60 cover element
61 portion of the cover element
62 cover element
63 bend
5 64 slits
65 center line
66 slits
67 slits
68 slits
10 69 slit
70 slits
71 kink lines
72 kink lines
73 slits
15 74 holes
75 portions
76 portions
77 portions
78 opening
20 79 adjacent portions
80 adjacent portions
81 three-layer regions
82 three-layer regions
83 double-layer regions
84 connection means
85 part of the edge
86 part of the edge
87 edge
88 edge
