FIELD OF INVENTION
This invention relates to a bulge free flexible intermediate bulk container after filling, storing and transporting of bulk powder or granular material.
BACKGROUND OF THE INVENTION
The use of flexible intermediate bulk containers to pack bulk quantities of powdered or flaked or granular materials for storage, transportation and for feeding to the process by handling with forklifts or other handling systems such as hoists or cranes, is very common world wide. The material used for the construction of such containers may be a woven synthetic fabric, cotton fabric, jute fabric etc. The general design of the container is a hollow tube, made out of plurality of panels or a single woven tube, rectangular or round in shape with top and bottom end walls having tubular chutes for filling and discharging the materials.
One persistent problem in the use of these flexible containers is the bulging factor of the container in material filled condition due to the elasticity of the fabrics used for constructing the container.
Generally all the fabrics have the nature of elongation ranging from 10 to 40%. When the material in quantities of one to two tons is filled, the load exerts the impact on the side walls of the container in the form of expansion and the resultant effect would be an improper ballooning form of the container and there by increasing the effective widths unevenly or disproportionately. This ballooning effect i.e. bulging of the

container creates the problems for transportation. The problems are different in different cases. In some cases it is very difficult to place in the truck body or export container inspite of following engineering designs and structure calculations, in some cases the containers (bags) get jammed up during road transportation, in some cases the bags could not be taken out of the trucks at the destinations, in some cases the desired number of bags could not be placed in the export container incurring heavy costs of freights, in some cases the storage space could not be judiciously utilised, in some cases the extra curvature of the filled bag touch the body of forklift while handling and get damaged and in some cases the fabric of the bag may get damaged or burst due to uneven stress and strain factors.
The present invention is directed towards the problem described above, wherein the arrest of bulging of the container when filled with material by a simple mechanism or technique involving a special design and fabrication so as to avoid the damage of the container, to economise the cost of transportation and to handle and store conveniently.
It is thus desirable to arrest the bulging of the container by identifying the vulnerable area and terminating the force exerted by the load of the material due to counter pulling effect of a common bonding ie., reinforcement panel.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provided a new version or improved version of a flexible bulk container without bulging to form a perfect square or rectangle when filled with material.

Another object of this invention is to provide a double side coated fabric with punched slots inside the container to arrest the impact of material filled.
Yet another object of this invention is to design a container convenient for movement of the material at the time of filling and discharge without any obstruction.
Yet other object of this invention is to provide a inner bag made out of relatively thinner gauge fabric with a double side coated fabric having punched slots and is placed inside a conventional flexible intermediate bulk container for packing special and expensive materials.
The invention provides a bulge free flexible intermediate bulk container for storing and transporting the bulk materials comprising panels, end joints are joined to form a square or rectangle container with plurality of lifting loops mounted on the upper side walls of the container at four cross corners. The end walls comprises opening at the center, and the fill or discharge means are stitched around the openings for facilitating material filling and discharge. A reinforcement in the form of a rectangular piece of fabric having plurality of slots are attached inside the container at four corners in order to arrest the bulging of side panels of the container.
Accordingly, the invention provides a flexible intermediate bulk container for packing powder or granular material for storage and transportation, said container comprising a top end wall and a bottom end wall, joined by a plurality of side walls, said top end wall being provided with a filling chute and a closure, said bottom end wall being provided with a discharge chute and a closure, characterized in that a rectangular piece of fabric having a

plurality of slots are provided at the inside corner of the said plurality of side walls to arrest the bulging of the said container when filled with material.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig 1 is a perspective view of a container according to the invention in a filled
condition.
Fig. 2 is another perspective view of a container similar to the one shown in fig.l but having two layers.
Fig. 3 is a top end wall (20) of the container wherein (21) is the mouth secured with a filling chute (31) and a closure.
Fig. 4 is a bottom end wall (25) of the container with opening at the center and discharge chute (24) with a closure (26).
Fig. 5 shows the perspective view of a rectangular piece of fabric (23) with double side coated and having punched slots (10).
Fig 6 is a perspective view of two rectangular pieces of fabric (23) fixed on a single entity meant for one full scape side wall (17) and two half portions of side walls (18) and (19) of the same panel forming two corners (6) of the container leaving gaps of (27) at both ends in length wise.
Fig. 7 is an over view form top of the container after joining the two side walls with four rectangular pieces of fabric (23) inside the corners of the containers.

The rectangular pieces of fabric (23) is preferably a strong double side coated, flexible synthetic woven fabric. The rectangular pieces of fabric (23) has a series of slots (10) and are shorter than container as shown in fig. 6.
A strong, flexible and synthetic woven fabric (30) having the dimensions based on the size of the container required, is employed so as to cover one side wall (17) and half of side wall (18) and (19) of the container. The fabric is marked as (17) and (18) by means of coloured tape lines (12) during weaving itself. And the lines (12) also guide to form corners (6) of the container when finished. Apart from the marked lines (12) two more lines (13) are given on all side walls at a distance from the corners (6) and parallel to the marked lines (12). These lines (13) are guidelines for stitching the rectangular pieces of fabric (23) at the corners.
Similarly another fabric (30 A) is taken to form side wall in full and half portions of side walls with marked lines (12) and (13) as shown in figures 6 and 7. Two lifting loops (5) are mounted at cross corners (6). Two rectangular pieces of fabric (23), (23A) are mounted on side walls.
As shown in Fig. 7 a complete tubular structure of the container is formed by joining the two panels (30) and (30 A) lengthwise at the marked line (29). Later the top end wall (20) with filling chute (31) and a tying tape (14) is fixed to the top side of the tubular structure of container. Then the bottom end wall (25) with discharge chute (24) with tying tape (15) and closure means (26) having the tying tape (16) are fixed to the main tubular structure of the container at the bottom end to form a complete flexible intermediate bulk container as shown in Fig.l.

Fig. 8 is a perspective view of a preferred embodiment mounted tubular structure as liner bag introduced in a relatively bigger size seam less conventional flexible intermediate bulk container. The top of the container as in Fig. 2 is shown without top end wall (20) to have an inside view.
Fig. 9 shows 2 types of conventional flexible intermediate bulk containers filled with material but without the four rectangular pieces at the corners.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention relates to a flexible intermediate bulk container having rectangular pieces of fabric (23) with plurality of slots (10) at the corners. The container is thus designed and fabricated with bottom to top end walls, (20), (25), joined to a plurality of side walls. The container comprises four lifting loops (5) made out of tough synthetic woven webbings, mounted on the top side at cross corners as shown in fig. 1.
This invention also provides a preferred container as illustrated in Fig. 2 having a double layered configuration. The inner container (8) being of lighter weight is made of synthetic woven fabric with less strength having the rectangular pieces of fabric (23) at the corners. This tubular structure (8) is devoid of any attachments other than the rectangular pieces of fabric (23) at the corners.
The outer tubular structure (7) is a flexible, strong woven fabric in tube form by means of plurality of side walls. The inner tubular structure (8) is placed inside the outer tube (7) and then the end walls (20) & (25) and the lifting loops (5) are fixed to form a special double layered container as shown in Fig.
2.

The rectangular pieces of fabric (23) is preferably a strong double side coated, flexible synthetic woven fabric. The rectangular pieces of fabric (23) has a series of slots (10) and are shorter than container as shown in fig. 6.
A strong, flexible and synthetic woven fabric (30) having the dimensions based on the size of the container required, is employed so as to cover one side wall (17) and half of side wall (18) and (19) of the container. The fabric is marked as (17) and (18) by means of coloured tape lines (12) during weaving itself. And the lines (12) also guide to form corners (6) of the container when finished. Apart from the marked lines (12) two more lines (13) are given on all side walls at a distance from the corners (6) and parallel to the marked lines (12). These lines (13) are guidelines for stitching the rectangular pieces of fabric (23) at the corners.
Similarly another fabric (30 A) is taken to form side wall in full and half portions of side walls with marked lines (12) and (13) as shown in figures 6 and 7. Two lifting loops (5) are mounted at cross corners (6). Two rectangular pieces of fabric (23), (23A) are mounted on side walls.
As shown in Fig. 7 a complete tubular structure of the container is formed by joining the two panels (30) and (30 A) lengthwise at the marked line (29). Later the top end wall (20) with filling chute (31) and a tying tape (14) is fixed to the top side of the tubular structure of container. Then the bottom end wall (25) with discharge chute (24) with tying tape (15) and closure means (26) having the tying tape (16) are fixed to the main tubular structure of the container at the bottom end to form a complete flexible intermediate bulk container as shown in Fig.l.

WE CLAIM:
1. A flexible intermediate bulk container for packing powder or granular materials for storage and transportation, said container comprising a top end wall and a bottom end wall, joined by a plurality of side walls, said top end wall being provided with a filling chute and a closure, said bottom end wall being provided with a discharge chute and a closure, characterized in that rectangular pieces of fabric (23) having a plurality of slots (10) are provided at the inside corners of the said plurality of side walls (17) to arrest the bulging of the said container when filled with material.
2. A flexible intermediate bulk container as claimed in claim 1 wherein, said container is provided with a plurality of lifting loops (5).
3. A flexible intermediate bulk container as claimed in claim 1 wherein said container has an inner container (8) and an outer tubular structure (7).
4. A flexible intermediate bulk container as claimed in claim 3 wherein, the said inner container (8) is preferably made of synthetic woven fabric.
5. A flexible intermediate bulk container as claimed in claim 3, wherein the said outer tubular structure (7) is preferably made of strong woven fabric.
6. The flexible intermediate bulk container as claimed in claim 1
wherein, said rectangular piece of fabric (23) is a strong double side coated,
flexible woven fabric*

7. The flexible intermediate bulk container as claimed in claim 1
wherein, said plurality of slots (10) are cold punched slots.
8. The flexible intermediate bulk container as claimed in claim 1,
wherein, said plurality of slots (10) are oval shaped slots.
9. The flexible intermediate bulk container as claimed in claim 1
wherein, said rectangular piece of fabric (23) fixed at the corners are shorter
than the side walls (17).
10. A flexible intermediate bulk container substantially as herein
described with reference to the accompanying drawings.