FIELD OF THE INVENTION
[0001] This invention relates to metal strap handling and disposal.
BACKGROUND OF THE INVENTION
[0002] Steel strapping is widely used for packaging by many industries including: aluminium,
brick, cotton, jute, manmade fibres and wool. Disposal of strap material used in
such industries is a major materials handling problem in terms of the collection,
storage and disposable of such strap material.
[0003] Strapping is presently disposed of by placing it in waste bins and the like. Used
or waste strapping invariably occupies far more space than its own volume and it is
difficult to compress without the use of special compacting equipment. It is also
difficult and dangerous to handle due to its springy nature.
BRIEF SUMMARY OF THE INVENTION
[0004] It is the object of the present invention to provide a used strap coiling mechanism
which will result in the alleviation of the disposal problems referred to above.
[0005] The invention therefore provides a metal strap coiling device comprising a driven
roller and a pinch roller biased towards each other by biasing means to define a nip
between said rollers into which the strapping to be coiled is introduced, deforming
means positioned behind the nip between said rollers for inducing the strapping to
form a self-closing coil, said biasing means including means which enables the nip
between said rollers to be enlarged against the action of said biasing means to facilitate
the passage of section modulus changes which, for example, occur when strapping seals,
deformed portions of the strap or the like pass between said rollers.
[0006] In one form of the invention, the pinch roller is rotatably mounted on a pivoted
arm which is biased by said biasing means towards said driven roller to define said
nip. Although it is less convenient, it will be appreciated that the driven roller
may be mounted on a pivoted assembly and biased towards the pinch roller to achieve
the same end.
[0007] The deforming means preferably comprises a further roller which is driven at the
same surface speed as the driven roller. In a preferred form of the invention, said
driven roller is serrated to minimize slipping between said strapping and said nip
rollers.
[0008] One of the more difficult problems encountered in coiling strapping having applied
seals is the deformation of the short strapping element which projects from the seal.
Unless this element is properly deformed, the strapping will not coil properly and
the strapping will not feed through the coiling device. For this reason the deforming
roller is also preferably serrated to engage and deform the strap projections in the
area of the seal to allow better formation of a coil of said strapping.
[0009] In a particularly preferred form of the invention, the deforming roller is mounted
on means which pivots about the axis of rotation of said driven roller, said means
being linked to said pivoted assembly so that said deforming roller is pivoted with
said pinch roller when section modulus changes are encountered.
[0010] The strap coiling mechanism preferably includes a curved deflector bar which serves
to guide the leading edge of the deformed strapping during initial formation of the
self-closing coil.
[0011] The mechanism is preferably mounted on an elevated frame so that a storage container
or drum may be located below the coiling region of the mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] One preferred form of the invention will now be described with reference to the accompanying
drawings in which:
Figure 1 is a sectional side view of the strap coiling mechanism embodying the invention;
Figure 2 is a front elevation of the strap coiling mechanism of Figure 1; and
Figure 3 is a side elevation of the mechanism in use.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] Referring firstly to Figure 1 of the drawings, the strap coiling mechanism will be
seen to comprise a driven roller 1 having a serrated peripheral surface (Figure 2),
a pinch roller 4 rotatably mounted on one extremity of a pivoted crank lever 8, the
pinch roller 4 being biased towards the driven roller 1 by means of a compression
spring 6 engaging the other end of the lever 8, the biasing force being adjustable
by means of an adjusting screw 7. A nip N is defined between the driven roller 1 and
the pinch roller 4 and the nip N receives strapping S to be coiled. In the event that
the strapping includes a seal S′ or other similar connecting device, the pinch roller
4 will be deflected away from the driven roller 1, against the action of the spring
6, to allow the passage of the seal S′ through the nip N.
[0015] A deforming roller 3 is rotatably mounted between a pair of said plates 10 which
are pivoted about the axis of the driven roller 1. The roller 3 is located behind
the nip N in a position which causes the strapping S to engage the serrated surface
of the deforming roller 3 to induce the strapping S to form a self closing coil C.
A curved deflector bar 5 is located in a position to guide the leading edge of the
deformed strapping S during the initial formation of the coil C.
[0016] The deforming roller 3 is driven at the same surface speed as the driven roller 1
by means of an idler gear 2, mounted on the rearmost plate 10 and which meshes with
gears attached to the shafts supporting the driven roller 1 and the deforming roller
3 and defining gear train G.
[0017] The strap coiling mechanism is driven by an electric motor E through a gearbox G
and a clutch C1. As shown in Figure 2 of the drawings, the driven roller 1 and the
deforming roller 3 are supported in bearings carried in supporting side plates P while
the pinch roller 4 is carried in bearings mounted at the ends of the crank arms 8.
[0018] The strap coiling mechanism is preferably mounted on an elevated frame F so that
a waste container W may be positioned below the exit region for the coil C when the
end of the strapping S is reached. It will be appreciated that a closed coil of strapping
such as hat shown in Figure 1 of the drawings will occupy far less volume within the
waste container W than an uncoiled length of strapping.
[0019] While in the above embodiments a deforming roller is used to induce a self-closing
coil of strapping S, any suitable deforming means may be used to achieve a similar
end. However, the use of a serrated surface deforming roller is preferred since it
more positively engages the seal area during the formation of the self-closing coil
in the strapping S. Similarly, while the pinch roller 4 has been shown as being deflectable
to allow the passage of strapping seals S′, similar results may be achieved by spring
biasing the driven roller 1 for pivotable or vertical movement with respect to the
pinch roller 4.
1. A metal strap coiling device comprising a driven roller (1) and a pinch roller
(4) biassed towards each other by biassing means (6) to define a nip (N) between said
rollers into which the strapping (S) to be coiled is introduced, deforming means (3)
positioned behind the nip (N) between said rollers for inducing the strapping to form
a self-closing coil (C), said biassing means (6) including means which enables the
nip between said rollers to be enlarged against the action of said biassing means
(6) to facilitate the passage of section modulus changes (S′ which occur when strapping
seals, deformed portions of the strap or the like pass between said rollers.
2. The device of claim 1, wherein said pinch roller (4) is rotatably mounted on a
pivoted arm (8) which is biassed by said biassing means (6) towards said driven roller
(1) to define said nip (N).
3. The device of claim 1 or 2, wherein said deforming means (3) comprises a further
roller (3) which is driven at the same surface speed as the driven roller (1).
4. The device of any preceding claim, wherein said driven roller (1) has a serrated
peripheral surface to minimize slipping between the strapping S and the nip rollers
(1,4).
5. The device of claim 3, wherein said further roller (3) has a serrated peripheral
surface.
6. The device of claim 3, wherein said deforming roller (3) is mounted on means (10)
which pivots about the axis of rotation of said driven roller (1), said means (10)
being linked to said pivoted arm (8) so that said deforming roller (3) is pivoted
with said pinch roller (4) when section modulus changes are encountered.
7. The device of any preceding claim, further comprising a curved deflector bar (5)
positioned to guide the leading edge of the deformed strapping (S) during the initial
formation of the self-closing coil (C).
8. A metal strap coiling means comprising a driven roller (1), a pinch roller (4)
rotatably mounted at one end of a crank lever (8) pivotally mounted on a frame supporting
said driven roller (1), biassing means (6) supported by said frame and engaging the
opposite end of said crank lever (8) to bias said pinch roller (4) towards said riven
roller (1), a deforming roller (3) rotatably mounted behind the nip (N) between said
driven roller (1) and said pinch roller (3) and positioned to engage the strapping
(S) fed from said nip (N) into a self-closing coil (C), said deforming roller (3)
being driven at substantially the same surface speed as said driven roller (1).
9. The device of claim 8, wherein said driven roller (1) and said deforming roller
(3) have serrated peripheral surfaces.