Note: Descriptions are shown in the official language in which they were submitted.
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Beam
The present invention relates to a beam with a fully and/or
partially closed profile exhibiting at least two sides.
A considerable need exists in many technical areas for beams
of low weight, high strength with regard to both resistance
to bending and resistance to compression, and advantageous
collapse characteristics. Such beams are desirable in the
vehicle industry, the construction industry, the road
equipment industry etc., and especially the passenger car
industry, since an advantageous weight-to-strength ratio
permits lower fuel consumption and advantageous collapse
characteristics or a considerable capacity to absorb high
energy in the course of deformation to a state in which the
beam may be regarded as having collapsed. This latter
characteristic is desirable in so-called impact protection
zones in passenger cars, buses and lorries or similar
vehicles.
The basis of the present invention is the problem of
satisfying the aforementioned requirements.
This problem is solved in accordance with the present
invention by the beam referred to by way of introduction, in
that the beam is profiled from a coiled sheet metal strip
which exhibits an elongated section of expanded metal along
at least one side of the finished profile, in that the
sections of the sheet metal strip connecting the sides are
unbroken, and in that both meeting edges of the sheet metal
strip are connected or attached to one another to form the
closed profile. All the sides exhibit one or more sections of
expanded metal. The sections connecting the sides are
unbroken. The sides are connected or attached to one another
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to form the closed profile. Two of the sides are connected to
one another by folding the unbroken edge sections. Two of the
sides are connected to one another by welding. When the beam
has a multi-sided closed profile, it is advantageous for the
corner sections to be unbroken and for the fold or connection
closing the profile to be situated at one of the corners in
the unbroken edge sections. The beam is profiled from a sheet
metal strip which exhibits an elongated section of expanded
metal on each side of the finished profile and an elongated
section of sheet metal strip at each corner.
A beam in accordance with the present invention provides
unimagined opportunities within many technical areas, where
components can be made appreciably lighter without in a~y way
having to ~eopardize the strength of the component in
question. Appreciably improved energy-absorbing
characteristics are also offered, since appreciably greater
energy is consumed or required to bring about the complete
collapse of a beam in accordance with the present invention
than in the case of conventional beam structures. A beam in
accordance with the present invention also permits economies
of both space and weight, which in turn lead to appreciably
better operating economy. A beam in accordance with the
present invention also permits the use of simpler and more
efficient installation and assembly methods.
The present invention is described below in greater detail
with reference to the accompanying drawings. Fig. 1 shows a
view from the side of an embodiment of a beam in accordance
with the present invention. Fig. 2 shows a view from another
side of the beam in Fig. 1. Fig. 3 shows a cross-section
through the beam in Figs. 1 and 2 to illustrate its
quadrangular profile. Fig. 4 shows on a large scale a part of
a section of strip metal in the beam in accordance with the
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previous Figures. Fig. 5 shows a line for the manufacture o~
beams in accordance with the invention.
The embodiment of a beam in accordance with the present
invention shown in the drawings may, in principle, be of
infinite length and of any desired profile, although it is
shown in Fig. 3 to have a quadrilateral and essentially
square profile. A beam in accordance with the present
invention may, as stated, exhibit any suitable profile, for
example a two-sided oval profile or elliptical profile, a
quadrilateral profile or a quadrangular profile in accordance
with the drawings, a three-sided profile and many variants
and combinations of such profiles. It is conceivable, for
example, to have a profile which consists in principle of a
number of triangular profiles, for example three triangular
profiles or even four triangular profiles, which are attached
or connected to one another in an appropriate fashion, for
example with their tips meeting one another. Quadrangular
profiles need not be square, of course, but may exhibit in
principle any quadrangular form. The angles in the
quadrilateral profiles also need not be 90~, but may be
angles other than right-angles.
The beam illustrated in the drawings is quadrilateral, as
already mentioned above, and has a section 1 of expanded
metal on each of the three sides and a section 2 of expanded
metal on the fourth side. The fourth side also exhibits a
folded section 3 of essentially conventional type. The
profile exhibits unbroken sections between the sides. The
folded section 3 engages in an essentially conventional
fashion in the two meeting, unbroken edge sections that are
obtained after profiling of the beam to the quadrangular form
shown.
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The folded section 3 may be replaced by some other form of
connection or folding. The connection may well consist of a
weld in the form of a spot weld or a seam weld. The choice of
connection or attachment depends largely on the choice of
material used for the metal strip.
Fig. 4 illustrates a part of the sections 1, 2 of expanded
metal in detail, and it can be appreciated from this detailed
Figure that the sections of expanded metal have a
conventional form with a number of holes between bridges or
connections 5 in the sheet metal itself.
It is also possible, of course, to have other types of
expanded metal structures, although the type illustrated is
the preferred type. It must be pointed out in this respect
that that the upward-facing curves in the bridges 5 are
displaced up and out of the plane of the drawing, whereas the
downward-facing curves of the bridges 5 are displaced inwards
and into the plane of the drawing, although they are
connected to one another in such a way that the upward-facing
curve is connected to the downward-facing curve.
It must also be pointed out that it is naturally not
necessary for the beam to exhibit sections of expanded metal
on all sides, but that it may be appropriate in certain cases
to have expanded metal on one or two sides, for example two
opposing sides, or on two or three ad~acent sides of a
quadrangular beam. It is also conceivable to have an oval
beam, in which one side exhibits a section of expanded metal,
whereas the other side is unbroken. The unbroken edge
sections may be provided with sections of expanded metal or
holes intended to lighten the structure.
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The sheet metal from which a beam in accordance with the
present invention is manufactured may consist of many
~ different materials, for example aluminium, or steel etc.
- 5 A beam in accordance with the present invention can be
manufactured in an expander, which makes it possible to
achieve sectlons of expanded metal that are separated by
unbroken sections of sheet metal, in con~unction with which a
profiling machine and a folding machine or a welding machine
are positioned directly after the expander in question. The
profiling machine and the folding machine or the welding
machine may be separate machines from the expander.
A beam in accordance with the present invention will exhibit
sufficiently good strength characteristics, and may be
manufactured at such low cost that it will be capable of
being used within the construction industry as a load-bearing
structural beam, where it can replace the wooden beams of
both small and large ~im~nSionS used today.
BUSINESS IDEA
Self-contained profiles of expanded metal and unperforated
plate are manufactured from a coil of sheet metal strip.
Expanded metal profiles with edges and/or strips of
unperforated plate are roller-formed. The invention allows
manufacturing of a large quantity of products.
APPLICATIONS
* pillars and beams for building constructions
* containers and buildings in steel and aluminium, for
example building platform accommodation
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* energy-absorbing supporting structures for road equipment,
for example light columns
* furniture frames
* tubular structures
* cable support system and protection (shielding), refining
elements and diffusers, etc.
* insulation of tunnels for noise absorption
* impact safety in the design of motor vehicles
* rib frames, for example in lightweight boats
PROPERTIES
* low weight
* low energy transmission (noise and heat)
* high energy absorption by deformation
* low-cost, rapid production in large quantities
* simple perforation and jointing, etc.
* flexibility of design and product qualities
GENERAL
* Machine investment cost depends on the thickness of the
metal strip, the width of the metal strip and the post-
production equipment
* A rotary expander has high production capacity
* Each unit can be produced at a lower cost compared to a
profile made from untreated metal strip of the same plate
thickness
* Processing and material savings give the product a surplus
* The invention offers wide scope for giving each product the
specific qualities demanded, and
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* The technique is today best suitable for metal strip of up
to 3-5 mm in thickness.
MANUFACTURING PROCESS
The aforementioned profiles can be manufactured in a straight
line from a coil of sheet metal strip. A production line can
consist of a rotary expander, a roller-former and, for
example, a high-frequency (HF) welding machine or an edge
folder followed by a cross-cutting machine. Sections of the
metal strip are expanded in the rotary expander. Areas of
unperforated metal are left between the expanded areas. A
self-contained profile, for example round or square, is
shaped in the roller-former. The unperforated area forms the
edges in cornered profiles. The profiles are sealed, for
example, with a weld or a folded seam. If a folded seam is
chosen, the seam is produced in the roller-forming process. A
welded seal is made as in the case of tube manufacturing,
using an HF weld. Other methods of profile sealing can be
used.
Many modifications are conceivable, of course, within the
scope of the idea of invention defined in the following
Patent Claims.
