Specification
Field of the invention
[0001] The present invention relates to a connecting element for establishing an electrically
conductive connection between two further elements. The invention further relates
to a method of manufacturing such connecting element.
Background
[0002] Connecting elements of the aforementioned type are used as part of grounding kits
for connecting a coaxial cable or a cable of another type in outdoor applications
to a ground potential. Especially, such grounding kits may be used for grounding cables
of cellular base stations and broadcast systems and the like. Such grounding is necessary
to protect people and equipment from damages in case of lightning strikes and to prevent
electrical potential differences to build up between the cable and other devices.
[0003] Disadvantageously, conventional grounding kits and their connection elements comprise
crimp joints between different electrical conductors which are to be connected with
each other. These crimp joints are comparatively complex to manufacture and do not
provide for a reliable mechanical and electrical connection of elements under certain
operational conditions.
[0004] US 2011/0076861 A1 discloses a laminar electrical connector, wherein a stack of superimposed metal strips
are joined into a unified body both structurally and electrically.
[0005] US 6,422,900 B1 discloses a connector assembly for coupling a continuous length of coaxial cable
to a bulkhead.
[0006] WO 2007/049834 A1 discloses a grounding wire which is surrounded by a stainless steel covering pipe.
[0007] Thus, it is an object of the present invention to provide an improved connecting
element and an improved method of manufacturing a connecting element which avoid the
disadvantages of the prior art.
Summary
[0008] According to the present invention, regarding a connecting element, this object is
achieved by the feature combination according to claim 1.
[0009] According to a preferred embodiment, the three or more layers of the connecting element
are arranged in a stacked configuration such that a sandwich-type assembly is obtained.
[0010] According to a further embodiment, at least one layer of the connecting element may
comprise a plurality of materials. However, according to further preferred embodiments,
at least one layer of the connecting element is made of a specific material, i.e.
does not comprise substantial portions of further materials.
[0011] According to an example, at least one layer, but preferably each layer, is comprised
of a portion of sheet metal made of the respective material. According to a further
embodiment, alternatively or in addition, at least one layer may be made of material
other than sheet metal, as long as sufficient electrical conductivity is ensured.
[0012] According to a further example, at least one layer or the sheet metal which represents
said layer, respectively, comprises a substantially rectangular shape wherein a width
and a length of said layer are large compared to a layer thickness of the respective
layer. For example, if L defines a length and W defines a width of the basically rectangular
portion of sheet metal defining a specific layer, the thickness d of said layer is
defined by d < L/10 and/or d < W/5. Thus, it is ensured, that the respective layer
may easily be bent, so that an increased flexibility for mounting the connecting element
is given in contrast to conventional solutions which comprise massive metal bars for
implementing a connecting element.
[0013] According to a further example, length L and width W may comprise a ratio of L /
W > 10. According to the invention, the stacked configuration of at least three layers
of the connecting element according to an embodiment is mechanically flexible as opposed
to monolithic connecting elements found in prior art, which facilitates mounting in
the field and avoids additional machining for adapting the connecting element to different
target systems. A particular advantage of the connecting element according to the
embodiments is the fact that at least three layers comprise different material which
enables to combine materials with different properties, preferably regarding mechanical
stability, in particular tensile strength, and regarding electrical conductivity.
[0014] For example, according to the principle of the embodiments, connecting elements may
be provided which comprise a very good (i.e., high) electrical conductivity and which
are thus ideally suited for grounding purposes or for establishing other electrical
connections (i.e., other than to ground potential). At the same time, the connecting
elements according to the embodiments comprise a comparatively high tensile strength
contributing to a mechanically robust configuration. For example, according to some
embodiments, maximum tensile strengths for the connecting element may be attained
which are much higher than the tensile strength of conventional connecting elements
comprising crimp joints.
[0015] According to a further preferred embodiment, at least one layer comprises copper
and/or aluminium, whereby a low electric, i.e. Ohmic, resistance is attained. According
to a further embodiment, a whole, i.e. complete, layer of the connecting element may
be made of a specific material such as e.g. copper or aluminium. However, it is also
possible to provide other material for implementing the layer such as alloys of copper
and/or aluminium and the like. According to a further embodiment, a layer in the sense
of the embodiments may also comprise different components such as sub-layers or the
like, i.e. a layer in the sense of the embodiments is not restricted to a monolithic
assembly as such.
[0016] According to a further preferred embodiment, at least one layer comprises a material
other than copper or aluminium, preferably a material with a higher tensile strength
than that of copper or aluminium. Particularly, it is preferred if at least one layer
of the connecting element comprises stainless steel. As such, stainless steel comprises
a lower electrical conductivity in comparison to copper or aluminium, however it comprises
an increased tensile strength. Thus, a combination of aluminium and stainless steel
(or copper and stainless steel) is particularly preferred, because it offers both
a good electrical conductivity and a good maximum tensile strength thus withstanding
high tensile forces. According to the invention, a plurality of layers of the connecting
element may be made of the same material or may comprise the same material. For example,
it is possible to provide a connecting element which comprises a first number of layers
made of aluminium, and at least one further layer which is made of a different material,
for example stainless steel or the like.
[0017] According to a further embodiment, there is no restriction regarding the order of
layers or materials within the stacked configuration of the plurality of layers defining
the connecting element. However, according to one embodiment, in order to avoid contact
corrosion between adjacent conductors such as the connecting element and e.g. a grounding
element (for example a foundation earth electrode) the connecting element is to be
connected to, it may be advantageous to place e.g. stainless steel material in the
outer layers of the stack configuration of the connecting element, and to place less
noble materials in the inner layers of the connecting element. For example, the outer
layers of the connecting element could be made of stainless steel, whereas the inner
layers could be made of copper or aluminium. Alternatively or in addition, the outer
layers may even comprise a noble metal or at least a thin (i.e. galvanized) layer
of noble metal such as silver to prevent contact corrosion.
[0018] According to a further embodiment, at least two layers have a same layer thickness,
which advantageously enables to provide a large number of identical components for
assembling a connecting element according to the embodiments. Alternatively, it is
also possible that at least two layers have different layer thickness which provides
further degrees of freedom regarding the construction of the connecting element.
[0019] Of course, it is also possible to provide different groups of layers, wherein each
group comprises layers of identical thickness, and wherein different groups are associated
with different layer thicknesses.
[0020] According to a further embodiment, at least one layer of the connecting element is
at least partly surrounded by a jacket, which may e.g. be made of electrically isolating
material. According to a preferred embodiment, all layers of the connecting element
are commonly surrounded by a jacket made of electrically isolating material which
protects the layers of the connecting element from environmental influences. A common
jacket of non-isolating, i.e. conductive material, such as a metallic mesh or the
like, is also possible, which contributes to mechanical stability of the stack arrangement
of the connecting element without affecting mechanical flexibility.
I.e., a jacket may also be configured to provide mechanical stability for the stacked
configuration of the various layers of the connecting element.
[0021] For example, it is possible that a common surrounding isolating jacket is the only
means for keeping the various layers of the connecting element together in their stacked
configuration. Alternatively or in addition thereto, a non-isolating jacket or metallic
clamps or the like are also possible.
[0022] Of course, additional means for stabilizing the stacked configuration may also be
provided. Such means may e.g. comprise soldering joints and/or welding joints and/or
riveted bolts between one or more adjacent layers, clamps, screw connections comprising
one or more adjacent layers and the like.
[0023] According to a further preferred embodiment, said connecting element comprises a
mounting section for connection to said further element. Said mounting section may
e.g. be configured for mechanical and electrically conductive connection to a body
unit of a grounding kit or a grounding element of a building such as an antenna tower
and the like.
[0024] According to a further embodiment, said mounting section comprises at least one hole
whereby a screw connection and/or fastening by means of a bolt and the like is enabled.
Alternatively or additionally, a threaded bolt may also be provided at the mounting
section. Advantageously, according to a further embodiment, at least one component
of said mounting section, i.e. a threaded bolt, may form an integral part of one or
more layers of the connecting element, whereby superior mechanical stability and a
low Ohmic resistance is ensured.
[0025] According to a further embodiment, for defining said mounting section, two groups
of said layers of the connecting element are formed, wherein in an end portion of
said connecting element both groups are arranged with a non-vanishing distance between
each other to define a receiving section for receiving a component of said further
element. I.e., in the receiving section, which is located between the different groups
of connecting elements, a connecting element of a body unit of the grounding kit or
the grounding element or the like may be arranged for connection with the connecting
element.
[0026] According to a further embodiment, a cross-section of the connecting element, particularly
an aggregated cross-section of all electrically conductive components or layers, respectively,
is equal to or greater than about 10 mm
2 (square millimeter), which ensures a sufficient electric conductivity for handling
electric currents, particularly surge currents during a lightning strike, without
damage to the connecting element.
[0027] According to a further embodiment, the connecting element comprises a tensile strength
(also referred to as "ultimate tensile strength", UTS) of about 2500 Newton or more.
The tensile strength is also denoted as physical parameter "Rm" and defines the maximum
stress that a material can withstand while being stretched before breaking. I.e.,
according to a preferred embodiment, the connecting element is designed such that
it can withstand tensile forces of about 2500 Newton or more without breaking.
[0028] According to a further embodiment, the connecting element comprises an electrical
resistance R of about 2 mOhm/m (milliohm per meter) or less, which ensures a particularly
low voltage drop in case of surge currents.
[0029] A further solution to the object of the present invention is given by a grounding
kit for connecting a cable to a grounding element. Such a grounding kit may e.g. be
used for grounding a conductor of a cable or the like. Of course, instead of grounding
(i.e. connecting to an electrical ground potential), generally, the grounding kit
may also be used to establish an electrically conductive connection between different
conductors, wherein said conductors are not required to comprise ground potential
or any kind of reference potential.
[0030] According to an embodiment, the grounding kit comprises at least one connecting element
according to the embodiments, and the grounding kit further comprises a body unit
which is configured for establishing an electrically conductive connection with a
component of said cable.
[0031] According to a further embodiment, said connecting element is detachably fixed to
said body unit, particularly by means of one or more screws and/or a clamping mechanism,
which facilitates easy installation of the grounding kit or the connecting element
in the field. I.e., connecting elements of different lengths may be chosen to be connected
with the body unit.
[0032] Particularly, it is beneficial to avoid crimping joints, which are comparatively
difficult to establish with high quality, at least in the field, and which do not
exhibit the same high tensile strength as the screw or bolt connections proposed according
to the embodiments.
[0033] According to a further embodiment, said connecting element is non-detachably fixed
to said body unit, particularly by means of welding, preferably ultrasonic welding.
Thus, both the body unit and the connecting element of the grounding kit may form
a monolithic conductor arrangement which is particularly robust.
[0034] According to a further embodiment, said body unit of the grounding kit enables to
establish a watertight electrically conductive connection with the component of said
cable. This may e.g. be achieved by said body unit comprising sealing means such us
EPDM (ethylene propylene diene monomer) and/or other types of rubber and/or mastic.
[0035] A further solution to the object of the present invention is given by a method as
defined in claim 15.
Brief description of the figures
[0036] Further features, aspects and advantages of the present invention are given in the
following detailed description with reference to the drawings in which:
- Figure 1a
- depicts a side view of a connecting element according to a first embodiment,
- Figure 1b to 1d
- each depict a further embodiment of the connecting element,
- Figure 2a to 2c
- depict different embodiments of end sections of the connecting element,
- Figure 3a
- depicts a side view of an end portion of the connecting element according to an embodiment
connected to a cable,
- Figure 3b
- depicts a partial cross-section of the configuration according to Figure 3a, and
- Figure 4
- depicts a schematic view of an operational scenario of a grounding kit according to
an embodiment.
Description of the embodiments
[0037] Figure 1a depicts a schematic side view of a connecting element 100 according to
a first embodiment. The connecting element 100 serves for establishing an electrically
conductive connection between two further elements, which are not depicted in figure
1a.
[0038] It is to be noted that the drawings comprise schematic depictions of the embodiments
and that the various elements depicted in the figures are not necessarily drawn to
scale. The connecting element 100 according to figure 1a comprises a first layer 102a
of a first material, and a second layer 102b of a second material, which is different
from the first material. The various layers 102a, 102b of the connecting element 100
are arranged in a stacked configuration as depicted by figure 1a, i.e. the first layer
is arranged on top of the second layer in the depiction of figure 1a. Both layers
102a, 102b are preferably made of sheet metal, wherein the first layer 102a is for
example made of stainless steel, and wherein the second layer 102b is made of aluminium.
[0039] The material combination of stainless steel and aluminium offers a comparatively
high mechanical robustness, particularly a high tensile strength, due to the stainless
steel layer 102a. Moreover, a good electrical conductivity is ensured by using aluminium
for the second layer 102b. Further, the layer configuration of a plurality of layers
102a, 102b, each of which may e.g. be comparatively thin such as e.g. 0.1 mm to e.g.
2.0 mm, advantageously results in a high mechanical flexibility so that the connecting
element 100 can easily be bent for installation purposes. At least one mounting section
106 is provided, which enables to establish a mechanical and/or electrical contact
between the connecting element 100 and further elements to be connected thereto.
[0040] Figure 1b depicts a connecting element 100a. The first layer 102a comprises a layer
thickness d2, whereas the second layer 102b comprises a layer thickness d1. Presently,
the layer thickness d2 is larger than the layer thickness d1. Each layer 102a, 102b
may comprise a substantially rectangular cross-section. However, different layers
may also exhibit different cross-sections or cross-sectional shapes. As can be seen
from figure 1b, the mounting section 106 may also comprise one or more holes arranged
within said layers 102a, 102b. Presently, each of both opposing end sections 104a,
104b comprises one hole, which enables mounting of said connecting element 100a by
means of a bolt or a threaded bolt/screw connection or the like.
[0041] Figure 1c depicts a schematic side view of a further embodiment 100b, wherein the
connecting element 100b comprises seven layers 102c, ..., 102d, which ensures a good
electrical conductivity and a high mechanical flexibility. In contrast to braided
wires of conventional connecting elements, the embodiment 100b does not require any
crimp joints, but may rather also be attached to other elements by means of screws
or bolts, which ensures both a low contact resistance and a mechanical robust connection
to these other elements.
[0042] Figure 1d depicts a connecting element 100c according to a further embodiment.
[0043] The outer layers 102a, 102c (i.e. in Fig. 1d the top and bottom layers) of the connecting
element 100c according to figure 1d are preferably made of stainless steel, wherein
an intermediate layer 102b that is arranged within said stacked configuration between
the outer layers 102a, 102c is e.g. made of copper or aluminium. Thus, a good electrical
conductivity is ensured, while it is prevented that material of the intermediate layer
102b may be contacted at an outer surface of the connecting element 100c (with exception
of the end sections of the connecting element 100c).
[0044] This advantageously avoids contact corrosion effects since stainless steel layers
102a, 102c reduce this undesired effect. At the same time, the stainless steel layers
102a, 102c advantageously contribute to the tensile strength of the connecting element
100c, while the intermediate aluminium or copper layer 102b effects a good electrical
conductivity.
[0045] Figure 2a shows an end section 104b of a connecting element according to a further
embodiment. As can be seen from figure 2a, a bolt or threaded bolt 106a may be provided
integrally with said third layer 102c. This may e.g. be attained by providing a sheet
metal for defining the layer 102c, by providing a threaded bolt 106a of the same or
a different, but weldable, material, and by welding both components 102c, 106a to
form one single monolithic component.
[0046] Further layers 102a, 102b are also provided, wherein layer 102a also is made of stainless
steel to avoid contact corrosion, and wherein layer 102b is again made of aluminium
or copper.
[0047] The end section 104b as depicted by figure 2a can e.g. be used for easy mounting
of the connecting element to a further element which e.g. comprises a hole or nut
portion that can cooperate with said threaded bolt 106a.
[0048] Figure 2b depicts a schematic view of one single layer of a connecting element according
to a further embodiment. The layer 102a has in its end section at least one hole 106b
which enables mounting by means of a screw connection or the like. Optionally, at
least one further hole may also be provided in the end section. At least one layer,
presently e.g. layer 102a of figure 2b, or the sheet metal which represents said layer
102a, respectively, comprises a substantially rectangular shape wherein a width W
and a length L of said layer 102a are large compared to a layer thickness d2 (fig.
1b) of the respective layer. For example, if L defines a length and W defines a width
of the basically rectangular portion of sheet metal defining a specific layer 102a,
the thickness of said layer is defined by d < L/10 and/or d < W/5. Thus, it is ensured,
that the respective layer 102a may easily be bent, so that an increased flexibility
for mounting the connecting element is given in contrast to conventional solutions
which comprise massive metal bars for implementing a connecting element. The length
L and width W may comprise a ratio of L / W > 10, which results in a rectangular strip-type
shape. Figure 2c schematically depicts a side view of a connecting element 100d according
to a further embodiment. In its end section 104b, three adjacent layers of the stack
configuration of connecting element 100d are combined to form a first group g1 of
layers, and three further layers of the connecting element 100d are combined to define
a second group g2. Presently, the groups g1, g2 together comprise all six layers of
the connecting element 100d. However, according to further embodiments, it is not
required that all layers of the connecting element 100d are comprised of one of the
groups g1, g2. For example, between groups g1, g2 or outside thereof (not shown) further
layers may be provided which contribute to an aggregated cross-section area and thus
to electrical conductivity, but which do not contribute to mounting the connecting
element 100d. Such further layers may also comprise a reduced length L (fig. 2b) as
compared to the layers forming part of the groups g1, g2 to prevent them from extending
into the end section 104b.
[0049] As depicted by figure 2c, the end sections of the different groups g1, g2 are spaced
apart by a non-vanishing distance d3 from each other, whereby a receiving section
106c is defined. The end sections 104b of the groups g1, g2 may also comprise through
holes 106b for applying a screw connection to a further mounting element that can
be introduced into the receiving section 106c.
[0050] According to a further embodiment, any of the end sections depicted by figure 2a,
figure 2b, figure 2c may be applied to either one end portion 104a, 104b or to both
end portions 104a, 104b of any connecting element described above. I.e., according
to an embodiment, a connecting element may have similar or identical end portions
or mounting sections 106 or different end portions or mounting sections.
[0051] Figure 3a depicts connecting element 100d in a mounting position at a body unit 200,
which is part of a grounding kit for a cable 400.
[0052] As can be seen, the body unit 200 is of the clamp type and comprises a basically
C-shaped cross section, also cf. figure 3b.
[0053] The body unit 200 is mounted on the cable 400 such that a radially inner section
of the body unit 200 (not shown) establishes electrically conductive contact with
an outer conductor (not shown) of the cable 400. For this purpose, portions of an
isolating jacket (not shown) of cable 400 must be removed to enable said contact.
[0054] The connecting element 100d is connected to the body unit 200 by means of two screws
106d, which are received in respective holes 106b (figure 2c) of the connecting element
100d. Due to its plurality of single layers, the connecting element 100d is mechanically
flexible and can thus easily be mounted at the body unit 200 and the cable 400. Nevertheless,
due to the aggregated cross section of the multiple layers, a good electrical connectivity
is achieved. Moreover, a good tensile strength is also attained, because one or more
layers may be formed of material having a greater tensile strength than the good electrical
conductors aluminium or copper.
[0055] Moreover, the screw connection 106d can easily be made in the field, whereby costs
for installing the connecting element 100d and the body unit 200 are reduced.
[0056] As already mentioned above, figure 3b depicts a partial cross-section of the arrangement
of figure 3a. It can be seen that by means of the screws 106d (figure 3a) both the
clamping mechanism of the body unit 200 is locked around the cable 400 and the electrical
and mechanical connection between the body unit 200 and the connecting element 100d
(figure 3a) is established by means of the screws 106d, which is advantageous since
no further components are required for locking the connecting element 100d to the
body unit 200 and for locking the body unit 200 to the cable 400. The configuration
of fig. 3a has the further advantage of a very large contact surface between electrically
conducting portions of the body unit 200 and the connecting element 100d, since surface
portions of both groups g1, g2 of layers are used for establishing the contact, whereby
a contact resistance is further reduced. Moreover, since both end sections of the
C-shaped clamp element of the body unit 200 are contacted by a respective layer group
g1, g2, the overall Ohmic resistance between the cable 400 and the connecting element
100d is even further reduced.
[0057] Figure 4 depicts a schematic view of an operational scenario of a grounding kit 1000
according to an embodiment.
[0058] The grounding kit 1000 comprises a body unit 200 as explained above with reference
to figure 3a, 3b and a connecting element according to any of the above explained
embodiments.
[0059] Figure 4 depicts an antenna tower 440 which carries a remote radio head 420 that
is connected to a base station antenna system 430. A base station unit 410 is arranged
on a ground floor, i.e. in a separate building arranged close to the antenna tower
440. The cable 400 establishes an electric and/or optic connection between the base
station unit 410 and the remote radio head 420. For protecting the units 410, 420,
430 against lightning strikes, the grounding kit 1000 according to the embodiments
is provided which establishes an electrically conductive connection between a radially
outer conductor of the cable 400, which may for example comprise a hybrid cable or
a coaxial cable, and a grounding element 300 of the antenna tower 440, which may e.g.
be integrated into a pedestal of the antenna tower 440 (for example as a foundation
earth electrode) or which may be directly connected to a steel frame construction
of the antenna tower 440 or the like. For contacting the cable 400 or its outer conductor
respectively, the body unit 200 as depicted by figure 3a, 3b is provided around the
cable 400. An electrically conductive connection between the body unit 200 and the
grounding element 300 of the antenna tower 440 is established by at least one connecting
element according to the embodiments, which is not shown in figure 4. For example,
connecting element 100d according to figure 3a may be used for establishing an electrically
conductive connection between the body unit 200, the cable 400, and the grounding
element 300 of the antenna tower 440. More than one grounding kit 1000 may be provided
for a cable (i.e. feeder cable 400) as depicted by Fig. 4. A first grounding kit may
e.g. be placed close to the antenna, a second grounding kit may e.g. be placed as
depicted by Fig. 4, and a third grounding kit may e.g. be placed close to the shelter
410, i.e. at a shelter entry, to provide further improved lightning protection for
all components.
[0060] Due to its mechanical flexibility, which is enabled by the multi-layer construction
according to the embodiments, an easy installation of the connecting element 100d
is enabled.
[0061] Moreover, due to the material combination over the various layers according to the
embodiments, both a good electrical conductivity, i.e. a low Ohmic resistance, and
a large tensile strength is achieved for the connecting element 100, 100a, 100b, 100c,
100d, which is important since tensile forces resulting from electromagnetic field
forces that may occur during a lightning strike may amount up to 2400 Newton and even
more.
[0062] In contrast to conventional connecting elements, which require crimp connections,
the connecting element according to the embodiments can be attached to and locked
at further elements 200, 300 by using screw connections or bolts or the like, which
are more robust than the crimp connections.
[0063] A particular advantage of the connecting element according to the embodiments is
its high mechanical flexibility which facilitates installation on site, i.e. in the
field.
[0064] According to an embodiment, by using dissimilar metals the highly conductive layers
102b (figure 1d) and the mechanical strong material layers (102a, 102c) are calculated
such that on one hand the effective conductivity of the overall connecting element
is equivalent to or higher than what is required by the relevant standards, which
e.g. require a copper cross-section of 16 mm
2 or above for sufficient electrical conductivity.
[0065] On the other hand, the overall tensile strength of the connecting element should
be high enough to survive the mechanical stress occurring during a lightning strike
(tensile forces due to currents of up to 100 kilo Ampere flowing through the connecting
element and their magnetic forces). The connecting element may be connected to a ground
bar 300 of a building such as an antenna tower 440 or the like, the ground bar 300
usually being made of copper or stainless steel. In many cases, the ground bar may
also be implemented in the form of a galvanized steel bar with a zinc surface. To
avoid contact corrosion between the ground bar 300 and the connecting element according
to the embodiments, the preferred embodiment proposes to use outer layers 102a, 102c
(figure 1d) of stainless steel (or even noble metal or noble metal coating, i.e. silver
coating), and one or more intermediate layers 102b of aluminium or copper, whereby
contact corrosion is minimized and at the same time a low resistance is obtained.
[0066] Due to avoiding crimp joints, the connecting element according to the embodiments
provides higher product reliability as compared to conventional systems. At the same
time, the electrical contact resistance is reduced which leads to an improved lightning
protection.
[0067] Also, due to the basically rectangular shape of the single layers and of the resulting
stack of layers forming the connecting element according to some embodiments, a comparatively
large outer surface is given for the connecting element, which improves heat dissipation
thus further enabling larger maximum currents for the connecting element according
to the embodiments.
[0068] Advantageously, the layer construction according to the embodiments may even be configured
in the field, i.e. by cutting respective preformed pieces of sheet metal. Moreover,
holes may e.g. be applied to the sheet metal by punching or drilling for enabling
a screw connecting and the like. Advantageously, the layers of the connecting element
according to an embodiment can be adapted with simple means or tools to different
sizes of through holes and regarding the number of holes for the screw connections.
Alternatively or in addition to screw connections, one or more layers of the connecting
element may e.g. be non-detachably attached to the body unit 200 of the grounding
kit, i.e. by welding, wherein a cost-effective ultrasonic welding process may be employed.
[0069] According to a further embodiment, a cross-section of the connecting element 100,
particularly an aggregated cross-section of all electrically conductive components
or layers 102a, 102b, respectively, is equal to or greater than about 10 mm
2 (square millimeter), which ensures a sufficient electric conductivity for handling
electric currents, particularly surge currents during a lightning strike, without
damage to the connecting element 100.
[0070] According to a further embodiment, the connecting element 100 comprises a tensile
strength (also referred to as "ultimate tensile strength", UTS) of about 2500 Newton
or more. The tensile strength is also denoted as physical parameter "Rm" and defines
the maximum stress that a material can withstand while being stretched before failing
/ breaking. I.e., according to a preferred embodiment, the connecting element 100
is designed such that it can withstand tensile forces of about 2500 Newton or more
without breaking.
[0071] According to a further embodiment, the connecting element 100 comprises an electrical
resistance R of about 2 mOhm/m (milliohm per meter) or less.
[0072] Any combinations of the aforementioned embodiments are also possible. Particularly,
the layer construction of the connecting element advantageously enables different
layers to contribute to an overall, i.e. aggregated, cross-section and/or electric
conductivity and/or tensile strength, wherein contributions to one or more of these
parameters of individual layers may differ from those contributions of another layer.
E.g., at least one layer 102a may primarily contribute to an overall low electric
resistance, while another layer 102b may primarily contribute to an overall high tensile
strength.
[0073] The description and drawings merely illustrate the principles of the invention. The
scope of the invention is defined by the appended claims.
1. Connecting element (100) for establishing an electrically conductive connection between
two further elements (200, 300), namely for connecting a body unit (200) of a grounding
kit (1000) with a grounding element (300), wherein said connecting element (100) comprises
at least three layers (102a, 102b, 102c) of electrically conductive material, wherein
at least two layers (102a, 102b) comprise different material, and wherein at least
two layers comprise the same material,
characterized in that said connecting element is mechanically flexible.
2. Connecting element (100) according to claim 1, wherein at least one layer (102a) comprises
copper and/or aluminium.
3. Connecting element (100) according to one of the preceding claims, wherein at least
one layer (102c) comprises a material other than copper or aluminium, preferably a
material with a higher tensile strength than that of copper or aluminium, particularly
stainless steel.
4. Connecting element (100) according to one of the preceding claims, wherein outer layers
(102a, 102c) of said connecting element (100) are made of stainless steel, and wherein
at least one inner layer (102b) of said connecting element (100), which is arranged
between said outer layers (102a, 102c), is made of aluminium or copper.
5. Connecting element (100) according to one of the preceding claims, wherein at least
two layers have a same or different layer thickness (d1, d2).
6. Connecting element (100) according to one of the preceding claims, wherein at least
one layer, preferably all layers, are at least partly surrounded by a jacket.
7. Connecting element (100) according to one of the preceding claims, wherein said connecting
element (100) comprises a mounting section (106) for connection to said further element
(200, 300).
8. Connecting element (100) according to claim 7, wherein said mounting section (106)
comprises at least one hole (106b) and/or a, preferably threaded, bolt (106a).
9. Connecting element (100) according to claim 7 or 8, wherein, for defining said mounting
section (106), two groups (g1, g2) of said layers are formed, and wherein in an end
portion (104b) of said connecting element (100) both groups (g1, g2) are arranged
with a non-vanishing distance (d3) between each other to define a receiving section
(106c) for receiving a component of said further elements (200, 300).
10. Connecting element (100) according to one of the preceding claims, wherein at least
one of the following criteria is met:
a. a cross-section of the connecting element (100), particularly an aggregated cross-section
of all electrically conductive components or layers (102a, 102b), respectively, is
equal to or greater than about 10 square millimetre,
b. the connecting element (100) comprises a tensile strength, preferably an ultimate
tensile strength, of about 2500 Newton or more,
c. the connecting element (100) comprises an electrical resistance of about 2 mOhm/m
or less.
11. Grounding kit (1000) for connecting a cable (400) to a grounding element (300), wherein
said grounding kit (1000) comprises at least one connecting element (100, 100a, 100b,
100c, 100d) according to one of the preceding claims, and wherein said grounding kit
(1000) further comprises a body unit (200) configured for establishing an electrically
conductive connection with a component of said cable (400).
12. Grounding kit (1000) according to claim 11, wherein said connecting element (100,
100a, 100b, 100c, 100d) is detachably fixed to said body unit (200), particularly
by means of one or more screws (106d) and/or a clamping mechanism.
13. Grounding kit (1000) according to claim 11, wherein said connecting element (100,
100a, 100b, 100c, 100d) is non-detachably fixed to said body unit (200), particularly
by means of welding, preferably ultrasonic welding.
14. Grounding kit (1000) according to one of the claims 11 to 13, wherein said body unit
(200) enables to establish a watertight electrically conductive connection with a
component of said cable (400).
15. Method of manufacturing a connecting element (100) for establishing an electrically
conductive connection between two further elements (200, 300), namely for connecting
a body unit (200) of a grounding kit (1000) with a grounding element (300), wherein
at least three layers (102a, 102b, 102c) of electrically conductive material are provided,
wherein at least two of said layers (102a, 102b) comprise different material, wherein
said at least two layers (102a, 102b) of electrically conductive material are provided
such that said connecting element (100) is mechanically flexible, and wherein at least
two layers comprise the same material.
1. Verbindungselement (100) für das Herstellen einer elektrisch leitfähigen Verbindung
zwischen zwei weiteren Elementen (200, 300), konkret für das Verbinden einer Gehäuseeinheit
(200) eines Erdungskits (1000) mit einem Erdungselement (300), wobei besagtes Verbindungselement
(100) mindestens drei Schichten (102a, 102b, 102c) elektrisch leitfähigen Materials
umfasst, wobei mindestens zwei Schichten (102a, 102b) verschiedene Materialien umfassen
und wobei mindestens zwei Schichten dasselbe Material umfassen, dadurch gekennzeichnet, dass besagtes Verbindungselement mechanisch flexibel ist.
2. Verbindungselement (100) nach Anspruch 1, wobei mindestens eine Schicht (102a) Kupfer
und/oder Aluminium umfasst.
3. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei mindestens eine
Schicht (102c) ein anderes Material als Kupfer oder Aluminium umfasst, vorzugsweise
ein Material mit einer höheren Zugtragfähigkeit als Kupfer oder Aluminium, namentlich
Edelstahl.
4. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei äußere Schichten
(102a, 102c) besagten Verbindungselements (100) aus Edelstahl gefertigt sind und wobei
mindestens eine innere, zwischen besagten äußeren Schichten (102a, 102c) angeordnete
Schicht (102b) des besagten Verbindungselements (100) aus Aluminium oder Kupfer hergestellt
ist.
5. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei mindestens zwei
Schichten dieselbe oder verschiedene Schichtdicken (d1, d2) haben.
6. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei mindestens eine
Schicht - vorzugsweise jedoch alle Schichten zumindest teilweise von einer Umhüllung
umgeben sind.
7. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei besagtes Verbindungselement
(100) einen Halterungsbereich (106) zum Verbinden mit besagtem weiteren Element (200,
300) umfasst.
8. Verbindungselement (100) nach Anspruch 7, wobei besagter Halterungsbereich (106) mindestens
ein Loch (106b) und/oder einen vorzugsweise mit einem Gewinde versehenen Bolzen (106a)
umfasst.
9. Verbindungselement (100) nach Anspruch 7 oder 8, wobei zum Definieren besagten Halterungsbereichs
(106) zwei Gruppen (g1, g2) besagter Schichten gebildet werden und wobei in einem
Endabschnitt (104b) besagten Verbindungselements (100) beide Gruppen (g1, g2) in einem
festen Abstand (d3) zwischen einander angeordnet sind, um einen Aufnahmeabschnitt
(106c) für die Aufnahme einer Komponente der besagten, weiteren Elemente (200, 300)
zu definieren.
10. Verbindungselement (100) nach einem der vorgenannten Ansprüche, wobei mindestens eines
der folgenden Kriterien erfüllt wird:
a. ein Querschnitt des Verbindungselements (100), konkret ein Gesamtquerschnitt aller
elektrisch leitfähigen Komponenten bzw. aller Schichten (102a, 102b) ist gleich oder
größer als rund 10 Quadratmillimeter,
b. das Verbindungselement (100) umfasst eine Zugtragfähigkeit, vorzugsweise Reißfestigkeit,
von rund 2500 Newton oder höher,
c. das Verbindungselement (100) umfasst einen elektrischen Widerstand von 2 mOhm/m
oder weniger.
11. Erdungskit (1000) für das Verbinden eines Kabels (400) mit einem Erdungselement (300),
wobei besagtes Erdungskit (1000) mindestens ein Verbindungselement (100, 100a, 100b,
100c, 100d) nach einem der vorgenannten Ansprüche umfasst und wobei besagtes Erdungskit
(1000) weiterhin eine Gehäuseeinheit (200) umfasst, die konfiguriert ist für das Herstellen
einer elektrisch leitfähigen Verbindung mit einer Komponente besagten Kabels (400).
12. Erdungskit (1000) nach Anspruch 11, wobei besagtes Verbindungselement (100, 100a,
100b, 100c, 100d) lösbar an besagter Gehäuseeinheit (200) befestigt ist, und zwar
konkret anhand einer oder mehrerer Schrauben (106d) und/oder Klemmenmechanismen.
13. Erdungskit (1000) nach Anspruch 11, wobei besagtes Verbindungselement (100, 100a,
100b, 100c, 100d) unlösbar an besagter Gehäuseeinheit (200) befestigt ist, und zwar
konkret anhand einer Verschweißung, vorzugsweise einer Ultaschallverschweißung.
14. Erdungskit (1000) nach einem der Ansprüche 11 bis 13, wobei es besagte Gehäuseeinheit
(200) ermöglicht, eine wasserdichte elektrisch leitfähige Verbindung mit einer Komponente
besagten Kabels (400) herzustellen.
15. Verfahren für die Herstellung eines Verbindungselements (100) für das Herstellen einer
elektrisch leitfähigen Verbindung zwischen zwei weiteren Elementen (200, 300), konkret
für das Verbinden einer Gehäuseeinheit (200) eines Erdungskits (1000) mit einem Erdungselement
(300), wobei mindestens drei Schichten (102a, 102b, 102c) elektrisch leitfähigen Materials
zur Verfügung gestellt werden, wobei mindestens zwei der besagten Schichten (102a,
102b) verschiedene Materialien umfassen, wobei die besagten, mindestens zwei Schichten
(102a, 102b) elektrisch leitfähigen Materials dergestalt zur Verfügung gestellt werden,
dass besagtes Verbindungselement (100) mechanisch flexibel ist, und wobei mindestens
zwei Schichten dasselbe Material umfassen.
1. Élément de connexion (100) destiné à établir une connexion électriquement conductrice
entre deux autres éléments (200, 300), c'est-à-dire destiné à connecter une unité
de corps (200) d'un kit de mise à la terre (1000) à un élément de mise à la terre
(300), dans lequel ledit élément de connexion (100) comprend au moins trois couches
(102a, 102b, 102c) de matériau électriquement conducteur, dans lequel au moins deux
couches (102a, 102b) comportent des matériaux différents, et dans lequel au moins
deux couches comportent le même matériau, caractérisé en ce que ledit élément de connexion est mécaniquement flexible.
2. Élément de connexion (100) selon la revendication 1, dans lequel au moins une couche
(102a) comporte du cuivre et/ou de l'aluminium.
3. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel au moins une couche (102c) comporte un matériau autre que le cuivre ou
l'aluminium, de préférence un matériau dont la résistance à la traction est supérieure
à celle du cuivre ou de l'aluminium, en particulier l'acier l'inoxydable.
4. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel les couches externes (102a, 102c) dudit élément de connexion (100) sont
constituées d'acier inoxydable, et dans lequel au moins une couche interne (102b)
dudit élément de connexion (100), qui est disposée entre lesdites couches externes
(102a, 102c), est constituée d'aluminium ou de cuivre.
5. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel au moins deux couches ont une épaisseur de couche identique ou différente
(d1, d2).
6. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel au moins une couche, et de préférence toutes les couches, sont entourées
au moins partiellement d'une gaine.
7. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel ledit élément de connexion (100) comprend une partie de montage (106)
destinée à la connexion audit autre élément (200, 300).
8. Élément de connexion (100) selon la revendication 7, dans lequel ladite partie de
montage (106) comprend au moins un trou (106b) et/ou un boulon (106a), fileté de préférence.
9. Élément de connexion (100) selon la revendication 7 ou 8, dans lequel, pour définir
ladite partie de montage (106), deux groupes (g1, g2) desdites couches sont formés,
et dans lequel dans une partie d'extrémité (104b) dudit élément de connexion (100)
les deux groupes (g1, g2) sont disposés à une distance stable (d3) l'un de l'autre
afin de définir une partie de réception (106c) destinée à recevoir un composant desdits
autres éléments (200, 300).
10. Élément de connexion (100) selon l'une quelconque des revendications précédentes,
dans lequel au moins l'un des critères suivants est satisfait :
a. une section droite de l'élément de connexion (100), en particulier une section
droite agrégée de tous les composants ou couches électriquement conducteurs (102a,
102b), respectivement, est égale ou supérieure à environ 10 millimètres carrés,
b. l'élément de connexion (100) comporte une résistance à la traction, de préférence
une limite de rupture, d'environ 2 500 Newton ou supérieure,
c. l'élément de connexion (100) comporte une résistance électrique d'environ 2 mOhm/m
ou inférieure.
11. Kit de mise à la terre (1000) destiné à connecter un câble (400) à un élément de mise
à la terre (300), dans lequel ledit kit de mise à la terre (1000) comprend au moins
un élément de connexion (100, 100a, 100b, 100c, 100d) selon l'une quelconque des revendications
précédentes, et dans lequel ledit kit de mise à la terre (1000) comprend en outre
une unité de corps (200) configurée pour établir une connexion électriquement conductrice
avec un composant dudit câble (400).
12. Kit de mise à la terre (1000) selon la revendication 11, dans lequel ledit élément
de connexion (100, 100a, 100b, 100c, 100d) est fixé de manière démontable à ladite
unité de corps (200), en particulier au moyen d'une ou plusieurs vis (106d) et/ou
d'un mécanisme de bridage.
13. Kit de mise à la terre (1000) selon la revendication 11, dans lequel ledit élément
de connexion (100, 100a, 100b, 100c, 100d) est fixé de manière non démontable à ladite
unité de corps (200), en particulier par soudage, de préférence par soudage par ultrasons.
14. Kit de mise à la terre (1000) selon l'une des revendications 11 à 13, dans lequel
ladite unité de corps (200) permet d'établir une connexion électriquement conductrice
étanche à l'eau avec un composant dudit câble (400).
15. Procédé de fabrication d'un élément de connexion (100) destiné à établir une connexion
électriquement conductrice entre deux autres éléments (200, 300), c'est-à-dire destiné
à connecter une unité de corps (200) d'un kit de mise à la terre (1000) à un élément
de mise à la terre (300), dans lequel au moins trois couches (102a, 102b ,102c) de
matériau électriquement conducteur sont prévues, dans lequel au moins deux desdites
couches (102a, 102b) comportent des matériaux différents, dans lequel lesdites au
moins deux couches (102a, 102b) de matériau électriquement conducteur sont prévues
de sorte que ledit élément de connexion (100) soit mécaniquement flexible, et dans
lequel au moins deux couches comportent le même matériau.