[0001] The invention relates to a flexible container of fabric material for transporting
and storing bulk cargo, which container comprises a shell, a bottom and a closable
filling opening, which container can be lifted from its upper end, and the joints
forming the container are made by seaming or gluing.
[0002] Such flexible containers, or so-called bulk sacks are manufactured either of a circularly
woven fabric or of a flat fabric. One general fabric materiaal is a circularly woven
polypropylene fabric. The bottom of a bulk sack and the lifting eyes are generally
formed by means of stich seams. Such bulk sacks are provided with a plastic inner
sack to make the bulk sack tight.
[0003] Bulk sacks are nowadays manufactured also of a coated fabric material or of a fabric
laminate. In these known bulk sacks, the coating or film surface is on the outer surface
of the fabric material, because of which achieving a fully tight bottom by seaming
is difficult and uncertain, since achieving a tight bottom in such a way that the
fabric surfaces are against each other, does generally not succeed. In these bulk
sacks known in prior art, the upper end is formed into a fold bundle, but since it
is difficult to connect the the fabric surfaces tightly, a so-called rider band has
been used for closing the upper end tightly. Another closing method used for the upper
end has been such that the edge of the upper end has been folded double and the outer
surfaces of the fabric material have been seamed against each other. The mouth of
the bulk sack is also in this embodiment still open, but although the fold closes
the upper end, it is not tight. Because of this, the seamed edge is covered with a
separate flap for achieving a tight structure.
[0004] In the bulk sack solutions known in prior art, in which the film surface is on the
outer surface of the fabric material, occurs such a disadvantage that if the film
surface is broken, the bulk sack is no longer tight. In such a bulk sack solution,
in which the customer her/himself folds the bulk sack after the filling and performs
the closing her/himself, such a disadvantage occurs that the filling of the bulk sack
is slow and the closing result is uncertain.
[0005] In bulk sack solutions, in which a separate inner sack is used, several problems
also occur. The filling and closing of the bulk sack is slow and it also easily damages
both during the filling and in the subsequent transportation and storage, since some
part of the inner sack remains uncovered and is thus especially sensitive to damage.
[0006] An object of the invention is to achieve an improvement relative to the bulk sack
solutions known at the moment. A more detailed object of the invention is to achieve
a bulk sack, in which the necessary tightness is realized in a reliable manner, whereby
the use of the inner sack is not necessary. Another object of the invention is to
provide a bulk sack, which makes an easy and fast filling of and lifting of the bulk
sack possible in a simple and reliable manner.
[0007] The objects of invention are obtained with a flexible container, which is mainly
characterized in that at least the inner surface of the container is made of a seamable
material, that the shell of the container is provided with a filling opening furnished
with a closing device and that the lifting part of the container is formed into a
united fold bundle.
[0008] In the flexible container according to the invention, the inner surface of the fabric
material is coated, a film has been laminated onto the inner surface of the fabric
material or a film has been joined onto the inner surface of the fabric material,
which film is at least partially fastened to the fabric. The outer surface of the
flexible container according to the invention is a basic fabric material, the outer
surface of the container is coated or a film has been laminated onto the outer surface
of the fabric material of the container.
[0009] In the container according to the invention, the filling device is a cuff, which
is permanently fastened to the outer or inner surface of the of container. The closing
device can also be a closing flap arranged near the filling opening, which flap is
partly fixed to the outer surface of the container and which covers the filling opening.
[0010] In the container according to the invention, the fold bundle extends downwardly from
the upper edge by a distance of at least 10 mm. The fold bundle is then advantageously
seamed uniform at least within this distance. However, this is not necessary, but
it is in principle sufficient that the fold bundle is seamed at least at its upper
part, whereby the remaining fold bundle can be unseamed. The fold bundle can be provided
with a hole for a lifting element. The fold bundle can also be provided with a scissors
device tightening the traction, or the fold bundle can be folded donwards and fastened
with a strap, whereby an opening is formed for the lifting element. The fold bundle
can also be tightened with a rope for forming a lifting eye, or a lifting link can
be fixed to the fold bundle by making a joint between the lifting link and the fold
bundle.
[0011] The container according to the invention can also be formed from a double folded
fabric material piece or from two fabric material pieces placed on top of each other
or from a broad fabric material piece bent into a tube. Bending a broad fabric material
piece into a tube in such a way that the film surface of a coated or laminated fabric
tube forms the inner surface of the tube, makes the seaming or gluing possible in
a very simple manner.
[0012] Several important advantages can be reached by means of the flexible container according
to the invention. The solution according to the invention makes the achievement of
a tight joint possible merely by the seaming or gluing of the inner surfaces of the
fabric material, whereby it is not necessary to ensure the external tightness of the
flexible container. The solution according to the invention also decreases the quantity
of the fabric material to be used and the manufacturing work, but in spite of this,
a better tightness is obtained. Owing to the reliable tightness, the use of an inner
sack in the bulk sack according to the invention is unnecessary. The bulk sack can
naturally be provided with an inner sack when so desired, if there are some special
reasons for using the inner sack, but the use of an inner sack in the solution of
the invention is in no way necessary.
[0013] In the bulk sack according to the invention, the lifting part is formed into a united
fold bundle in connection with the manufacturing of the bulk sack, and a lifting element
known per se is joined to the fold bundle. The bulk sack according to the invention
is provided with a slot located on the shell, which slot acts as a filling opening.
Such a filling opening is closed with a closing device in a mariner suitable for invention.
[0014] In the bulk sack according to the invention, the fabric material protects the film
part acting as an inner surface, and because of this the tightness remains better
in case external damage is caused for the bulk sack.
[0015] The bulk sack solution according to the invention speeds up the filling of the bulk
sack and facilitates as well as ensures a good closing result. When compared to these
features, in earlier solutions, in which a separate inner sack is used, both the filling
and the closing of the bulk sack is slow. In addition, the inner sack damages easily
both during the filling and the subsequent transportation and storage, since some
part of the inner sack remains uncovered and is thus very sensitive to damage.
[0016] The invention is described in more detail with reference to certain preferable embodiments
shown in the figures of the accompanyin drawings, to which embodiments the invention
is not intended to solely limit.
[0017] Fig. 1 shows a certain preferable embodiment of a sack blank of a bulk sack according
to the invention.
[0018] Fig. 2 shows another preferable embodiment of a sack blank of a bulk sack according
to the invention.
[0019] Fig. 3 shows a third preferable embodiment of a sack blank of a bulk sack according
to the invention.
[0020] Fig. 4 shows a certain bulk sack according to the invention. in which the upper end
of the bulk sack is formed in a certain preferable manner and correspondingly the
triangles of the bottom of the bulk sack in a certain preferable embodiment.
[0021] Fig. 5 shows a certain alternative embodiment for fastening the triangles of the
bottom of the bulk sack.
[0022] Fig. 6 shows another preferable embodiment of the lifting-part solution of the bulk
sack according to the invention.
[0023] Fig. 7 shows a third preferable embodiment of the lifting-part solution of the bulk
sack according to the invention.
[0024] Fig. 8 shows a fourth preferable embodiment of the lifting-part solution of the bulk
sack according to the invention.
[0025] Fig. 9 shows a fifth preferable embodiment of the lifting-part solution of the bulk
sack according to the invention.
[0026] In the embodiment of Fig 1, the sack blank of a bulk sack has generally been marked
with a reference number 10a. In this embodiment, the sack blank 10a is formed from
a double folded fabric material piece. The bulk sack 10a is thus provided with a shell
11 and a fold on a bottom portion 12. The fabric material according to the invention
is comprised of a basic material, whose inner surface is formed of a sealable material.
In one embodiment, the inside of the fabric material is coated. In another embodiment
a film has been laminated on the inside of the fabric material. In a third embodiment,
a film has been joined to the inside of the fabric material, which film is at least
partly fastened to the fabric. The outer surface of the fabric material is in a certain
embodiment only a basic fabric material. In a third embodiment, a film has been laminated
on the outer surface of the fabric material.
[0027] In accordance with Fig. 1, a slot is formed on the shell of the bulk sack 10a and
preferebly in the upper portion of the shell 11 for a filling opening. The edges of
shell 11 are seamed with seams 14 and its open upper portion 13 with a seam 14, whereby
a completely tight bulk sack bland 10a is formed. The edge seams 14 can also be glue
seams, and in addition to seaming, the upper portion can be closed tight also by gluing
or with a double-sided tape.
[0028] In the embodiment of Fig. 2, bulk sack blank 10b is formed of two separate fabric
material pieces placed on top of each other, in which case also an open bottom portion
12 must be seamed or glued with a seam 14. The bottom portion 12 can also be provided
with a bottom flap, when needed. The other features of the embodiment shown in Fig.
2 correspond to those shown in Fig. 1.
[0029] In the embodiment of Fig. 3, a bulk sack blank 10c is comprised of a sufficiently
broad fabric material piece, which is bent into a tube and seamed or glued only at
its one edge wiht a seam 14. The other features of Fig. 3 correspond to those shown
in Fig. 2. The broad fabric material piece can alternatively be bent into a tube so
that the edge of the seamed or glued tube is not provided with a vertical seam, but
the seams are located in the lower and upper portions of the bent tube. Also in this
embodiment, a slot 15 is formed in the manner shown in Fig. 3.
[0030] In accordance with Fig. 4, bottom triangles 17 of a bulk sack are folded against
the sides of a shell 11 and joined to the sides within the whole range of the bottom
triangles 17 or only partially. The bottom triangles 17 can be formed e.g. on a mandrel.
When a bulk sack blank 10a,10b or 10c is drawn on the mandrel, the triangles thus
formed can be bent against the sides of the shell 11. The bottom triangles 17 must
naturally be performed before the joining of the upper portion.
[0031] Around a slot 15 is formed a suitable closing device, such as a cuff or a closing
flap 16, which is fastened either to the inner or outer surface of the bulk sack 10
so that a tight joint is formed relative to the surface. Such a joint goes round the
entire slot 15. After the filling of the bulk sack 10, the cuff is closed e.g. by
seaming, whereby the bulk sack 10 is completely tight. When the closing flap is used,
a closing flap is joined to the upper portion or one edge of the slot 15, and when
the bulk sack 10 is filled, the slot 15 is closed with the closing flap 16 either
by seaming, gluing or with a double-sided tape. A separate flap, such as a tape, can
also naturally be used as the closing flap, but a closing flap fixed beforehand is
more practical.
[0032] In accordance with Fig. 4, the upper portion of the bulk sack is folded, whereby
a tight fold bundle 18 is formed. In Fig. 4, the fold bundle 18 is provided with a
tight cuff 19. The use of the tight cuff 19 is not necessary, since the surfaces of
the fold gaps can be joined to each other so that the fold bundle 18 is uniform and
retains its form as such. In Fig. 4, a hole 20 is formed on the fold bundle 18 for
a lifting element.
[0033] Fig. 5 is otherwise similar to Fig. 4, but in this embodiment the bottom triangles
are folded against a bottom 12 of the bulk sack
[0034] In the embodiments of Fig. 4 and 5, the lifting element can be joined to the fold
bundle e.g. by threading a lifting link through the hole 20 and the ends of the lifting
link are joined together in a suitable manner. E.g. a rope can be used as the lifting
link, whose ends are tied together, or a metallic hook, whose ends are joined together.
[0035] In the embodiment of Fig. 6, a scissors lifting device 21 has been used, which is
fastened to the fold bundle 18. The scissors lifting device tightens up, when it is
subjected to a lifting movement, i.e. the scissors lifting device 21 is subjected
to traction.
[0036] In the embodiment of Fig. 7, the fold bundle 18 is bent into a curve, whereby the
fold bundle 18 is formed of two branches 18a and 18b. The bent fold bundle 18 is fastened
with a strap 22. whereby the branches 18a and 18b form an opening 23, through which
a lifting element can be threaded. The gap 24 between the branches 18a and 18b can
be seamed, glued or furnished with a double-sided tape. The end of the branch 18b
of the fold bundle 18 bent downwards can be reinforced with a thicknening portion
25. Such a reinforcement can be performed before forming the fold e.g. by placing
a film strip across the track. This creates a key effect when lifting the bulk sack
10, whereby traction is formed at the lifting part of the bulk sack 10.
[0037] In the embodiment of Fig. 8, a lifting link 26 is fixed to the fold bundle 18. A
joint 27 between the lifting link 26 and the fold bundle 18 can be made by gluing,
seaming, even by sewing or riveting as long as care is taken of the fact that in those
joining modes, in which the joining mode perforates the fold bundle 18, a uniform
seam remains also below the holes formed.
[0038] In the embodiment of Fig. 9, the fold bundle 18 is formed such that the fold bundle
18 expands upward, preferably conically upward. Below the conical fold bundle 18 is
placed a tightning link or a closing device 18 or some other corresponding closing
device. Before closing the tightening link 28, a lifting link 26 is threaded in place.
When the lifting link is lifted, the tightening link 28 lifts slightly upward on the
neck of the bulk sack and is finally locked on the conical part of the upper end of
the fold bundle. The closing device can be a one-part locked ring or e.g. a closing
device made of two pieces.
[0039] Only certain preferred embodiments of the invention have been described above, and
it is obvious to those skilled in art that several modifications are possible within
the inventive idea defined in the enclosed patent claims.
[0040] The invention relates to a flexible container (10) of fabric material for transporting
and storing bulk cargo. The container (10) comprises a shell (11) a bottom (12) and
a closable filling opening (15). The container (10) can be lifted from its upper end,
and the joints forming the container (10) are made by seaming or gluing. At least
the inner surface of the container (10) is made of a seamable material, and the shell
(11) of the container (10) is provided with a filling opening (15). The lifting part
of the container (10) is formed into a united fold bundle (18).
1. A flexible container (10) of fabric material for transporting and storing bulk cargo,
which container (10) comprises a shell (11), a bottom (12) and a closable filling
opening (15), which container (10) can be lifted from its upper end, and the joints
forming the container (10) are made by seaming or gluing.
2. A container according to Claim 1, characterized in that the inner surface of the fabric material of the container (10) is coated.
3. A container according to Claim 1, characterized in that a film has been laminated on the inner surface of the fabric material of
the container (10).
4. A container according to Claim 1, characterized in that a film has been joined on the inner surface of the fabric material of the
container (10), which film is at least partly fixed to the fabric.
5. A container according to any of the Claims 1-4, characterized in that the outer surface of the container is a basic fabric material.
6. A container according to any of the Claims 1-4, characterized in that the outer surface of the fabric material of the container (10) is coated.
7. A container according to any of the Claims 1-4, characterized in that a film has been laminated on the outer surface of the fabric material of
the container (10).
8. A container according to any of the Claims 1-7, characterized in that the closing device (10) is a cuff surrounding the filling opening, which
is permanently joined to the outer or inner surface of the container (10).
9. A container according to any of the Claims 1-7, characterized in that the closing device (16) is a closing flap placed near the filling opening
(15), which flap is partially fixed to the outer surface of the container (10) and
covers the filling opening (15).
10. A container according to any of the Claims 1-9, characterized in that the fold bundle (18) extends from its upper edge downward by a distance of
at least 10 mm.
11. A container according to any of the Claims 1-10, characterized in that the fold bundle (18) is provided with a hole (20) for the lifting element.
12. A container according to any of the Claims 1-10, characterized in that a scissors device tightening via traction (21) is integrated with the fold
bundle (18).
13. A container according to any of the Claims 1-10, characterized in that the fold bundle (18) is folded downward and fastened with a strap (22), whereby
an opening (23) is formed for the lifting element.
14. A container according to any of the Claims 1-10, characterized in that the fold bundle (18) is tightened with a rope for forming a lifting eye.
15. A container according to any of the Claims 1-10, characterized in that a lifting link (26) is joined to the fold bundle (18).
16. A container according to any of the Claims 1-10, characterized in that the fold bundle (18) is formed into an upwardly expanding fold bundle and
that the lifting link (26) is locked into the fold bundle (18) by means of a closing
device (28) fitted below its expanding part.
17. A container according to any of the Claims 1-16, characterized in that the container (10) is formed of a double folded fabric material piece.
18. A container according to any of the Claims 1-16, characterized in that the container (10) is formed of two fabric material pieces placed on top
of each other.
19. A container according to any of the Claims 1-16, characterized in that the container is formed of a broad fabric material piece, which is bent into
a tube.