[0001] A looped lifting and strapping sling for lifting two loads of primarily the same
size and weight
[0002] The present invention relates to a looped lifting and strapping sling which is intended
for lifting two loads of primarily the same size and weight, for example loads made
up of bales, sacks or pipes, one end of the sling having been shaped into a lifting
loop and there being at the opposite end an eye formed between two layers of material;
thus, in the lifting position of the lifting and strapping sling the sling part between
the eye and the lifting loop encircles both loads, the lifting loop having been passed
up between the loads and through the eye located above and between the loads.
[0003] So-called clover-leaf slings are commonly used for lifting sacks. Such slings cannot,
however, be lifted by means of an ordinary hoist but a spreading hoist is needed,
i.e. four hooks supported by a framework, the hooks lifting the clover-leaf sling
at four corners.
[0004] Also commonly used is a single loop one end of which is passed through the other
end of the loop, whereby a slip knot which during lifting tightens around the load
being lifted is obtained. With a slip knot, however, part of the strength of the lifting
sling is wasted and, furthermore, the tightening point may damage the goods being
lifted. In .slip-noose lifting the load is not always in equilibrium, which may make
the lifting insecure.
[0005] From British Patent 1 463 055 there is also known a lifting sling having at one end
a lifting loop which is passed through an aperture at the opposite end, whereby two
loops are formed, both of which encircle a separate load. A platform having a central
aperture for the lifting loop is used as the base for the loads. The size of the aperture
and the dimensions and the type of the sling material are selected in such a way that
friction between the lifting loop and the edges of the aperture prevents the lifting
loop from moving in the aperture after the lifting loop has been removed from the
hoist and the tension on the lifting loop has ceased.
[0006] The object of the present invention is to provide a lifting and strapping sling which
is easy to use and reliable and at the same time has so economical a manufacturing
technique that it can be discarded after use.
[0007] This has been accomplished by a lifting and strapping sling the principal characteristics
of which are given in accompanying claim 1.
[0008] The lifting and strapping sling according to the invention is thus provided with
a tying band one end of which is fastened to the strapping sling, preferably at the
stitching or suchlike by means of which one end of the sling is formed into a lifting
loop, or close to the stitching or suchlike. By means of this tying band the lifting
loop is tied to the load-strapping sling while the lifting loop is in the lifting
position, tightened around the load, whereby a binding is formed which keeps the load
together also during transportation between liftings.
[0009] The point at which the tying band is fastened and which at the same time is preferably
the stitching by means of which the lifting loop has been formed, is fitted at such
a point in the sling that, under the effect of the tension produced by the lifting,
it rises close to the eye but remains below it. The eye, for its part, is located
between the loads at the height of their upper edges. Thus it is easy to tie .the
tying band to the load-strapping sling. This knot of the tying band does not open
even in repeated liftings but keeps the load together all the time and does not damage
the structure of the sling. Until the tying band is tied, its free end is attached
lightly with adhesive tape or the like inside the lifting loop, from where it can
easily be pulled out for tying to the load-strapping sling.
[0010] The locking of the lifting and strapping sling by means of a tying band is done while
the load is hanging from the lifting hook, at which time it is also in the tensioned
state.
[0011] Owing to the eye formed in the lifting and strapping sling the load is lifted in
an upright position. In this manner the ultimate strength of the lifting device can
be completely exploited. Furthermore, the lifting takes place in such a way that the
load is always in equilibrium, which increases the security of the lifting work.
[0012] The lifting and strapping sling according to the invention is preferably made from
a band of synthetic material, but it can also be made from, for example, rope.
[0013] This lifting and strapping sling is very suitable for the lifting and strapping of
products in sacks, for example cement and fertilizer sacks. For example, fertilizer
sacks can in this way be strapped into bundles which can be handled by a tractor.
Likewise, this lifting and strapping sling is suitable for strapping cellulose bales
and also for the bundling and lifting of pipes.
[0014] By using two lifting and strapping slings for bundling and lifting the same load
it is possible to handle even floppy sacks.
[0015] The lifting and strapping sling according to the invention is described below in
greater detail in the form of a preferred embodiment and with reference to the accompanying
figures, in which
Figure 1 is a perspective representation of the lifting and strapping sling in the
resting position;
Figure 2 depicts the sling according to Figure 1 at the stage at which the sling is
being set into the position in which it can be fitted around the loads;
Figure 3 depicts the sling ready for being fitted around the loads;
Figure 4 depicts the sling fitted around the loads, at the lifting stage; and
Figure 5 depicts the sling around the load, after lifting, and tied by means of the
tying band to the sling part passing over the loads.
[0016] In the figures, the lifting and strapping sling is indicated by reference numeral
1, that part of the sling which passes around the load by 2, and its lifting loop
part by 3. The stitching by means of which the lifting loop 3 is formed is indicated
by 4, the eye by 5, and the tying band by 6.
[0017] The figures illustrate the stage of passing the lifting and strapping sling around
the load, the lifting stage, and the transportation stage between liftings. Before
the sling is fitted around the load the said lifting loop end is passed through the
eye and tightened only so much that the lifting loops remain larger than the loads
to be lifted, whereupon it is easy to fit the sling around the load. Figure 5 shows
how the tying band 6 has been pulled out from inside the lifting loop 2, been passed
from the left side of the loop, under the sling part 2 which encircles the load, to
the right side of the loop, and between the thus formed oblique tying-band part and
the loop, whereby a knot locking the sling in a tightened position has been formed.
The tying is carried out at the stage according to Figure 4. To ensure tightening,
the sling may be provided with two tying bands 6.
[0018] In the embodiment illustrated, the load is made up of cement sacks. As pointed out
above, the load may also be made up of floppy and slippery plastic sacks, in which
case two or more slings are used for lifting the same load. In this case it is also
necessary to select a suitable sling material which clings to the plastic surface.
1. A looped lifting and strapping sling (1) for lifting two loads of substantially
the same size and weight, for example loads made up of bales, sacks or pipes, one
end of the sling (1) having been formed into a lifting loop (3) and there having been
formed at the opposite end an eye (5) between two layers of material, in which case
in the lifting position of the lifting and strapping sling (1) the sling part (2)
between the eye and the lifting loop encircles both loads, the lifting loop (3) having
been passed up between the loads and through the eye (5) located above and between
the loads,
characterized in that in order to tie the lifting loop (3) to the sling part (2) in
order to keep the lifting and strapping sling (1) in the tightened state between liftings,
there is a tying band (6) fastened preferably at the stitching (4) or similar means
which delimits the lifting loop (3).
2. A lifting and strapping sling according to claim 1, characterized in that the joint
stitching (4) or similar means of the lifting loop (3) and the tying band is fitted
so as to be located at a point which in the lifting position is approximately in alignment
with the eye (5), slightly below it.
3. A lifting and strapping sling according to claim 1, characterized in that there
are two tying bands (6) fastened to the lifting and strapping sling.