GB2228468A

GB2228468A - Bag for transport container

Info

Publication number: GB2228468A
Application number: GB9000502A
Authority: GB
Inventors: Keiji Ishii
Original assignee: APS CO Ltd
Current assignee: APS CO Ltd
Priority date: 1989-01-10
Filing date: 1990-01-09
Publication date: 1990-08-29
Anticipated expiration: 2010-01-09
Also published as: GB2228468B; GB9000502D0; CA2007045A1; AU632524B2; CA2007045C; AU4787090A

Abstract

In a bag fitted in a transport container, the rear wall (10b) of this bag is prevented from bulging out backwardly under the pressure of the weight of a particulate cargo such as cereals stowed in the bag by providing the bag with an insertion piece (13a) extending downwardly from the lower edge of an auxiliary sheet (13), Figs. 4, 6b, and inserted between the bottom wall (10e) of the bag and the bottom wall of the container, and connected (16, 17) under tension to the bottom wall (10e). In a modification, Fig. 14, a lower insertion piece (13a) and lateral insertion pieces (13b) extending integrally from the lower edge and the lateral edges of the bag rear wall are connected (16, 17 and 25, 26) under tension to the bag bottom and side walls (10e, 10d). <IMAGE>

Description

DESCRIPTION INTERIOR BAG FOR A CONTAINER This invention relates to an interior bag for a container, and more particularly to a container interior bag to be fitted in a general-purpose container provided with hinged door or doors adapted to permit conveyance of cargo in and out therethrough and used for admitting a particular article such as cereal for bulk shipment.

In the transportation of cereals and raw materials for industrial products such as, for example, granular synthetic resins and particulate raw materials, there have been used containers exclusively adapted for such special kinds of cargo as mentioned above. Since these containers accept only specified kinds of cargo, they encounter the inconvenience that after they have been used in transporting cereals, for example, they are returned empty from the destinations to the points of origin. In today's marine transport conducted on a large scale as in the transport of cereals, the fact that empty containers are transported constitutes itself a cause for immense diseconomy and pose a serious hindrance to the reduction in cost of transport.

In the circumstance, the practice of transporting cereals in general-purpose containers intended primarily for ordinary kinds of cargo has come to prevail in recent years.

This utilization of such general-purpose containers resorts to a method which, as illustrated in Figure 1, comprises fitting in a container 1 an interior bag 4 made of a sheet of such a resinous material as polyethylene in a shape substantially identical with the internal contour of the container 1 and stowing a cereal S in the interior bag 4. In accordance with this method, when the container, on completing the transport of the cereal, is stripped of the interior bag 4, it resumes the original form of an ordinary container and can be used on its return course for the transport other kind of ordinary cargo. This fact enhances the efficiency of use in a large measure and lowers the cost of transport.

One fault found in this practice of using the interior bag resides in the fact that when a weighty granular or otherwise particulate cargo such as cereals is placed in this interior bag, it lacks strength enough to bear the weight of the cargo and consequently swells outward as illustrated in Figure 2.

In the case of the general-purpose container, this swell of the interior bag has its effect to bear on the hinged doors in the rear part of the container, with the possible result that the swell interferes with the opening and shutting of the hinged doors and the inner pressure (the pressure from the weight of cargo) causes the hinged door to burst open when the hinged doors are unlocked.

As one way of preventing the interior bag, particularly the rear face part thereof confronting the hinged door, from swelling under the inner pressure, there has been a method for precluding a rear surface 5 of the interior bag 4 swelling by passing a multiplicity of supporting bars 3 horizontally across a rear opening part 2 of the container 1 as spaced in the vertical direction as illustrated in Figures 3A and 3B.

The method which resorts to the supporting bars 3 resides in utilizing grooves formed in the longitudinal direction one each on the inner sides of vertical frames 6 erected upright as opposed to each other on the opposite sides of the rear opening part 2 of the container (grooves shaped by the formation of reinforcing ribs) for admitting the opposite ends of the supporting bars 3 thereby allowing the supporting bars 3 to be laid horizontally across the opening part. The actual work involved therein is easy because it is limited to that of fitting the supporting bars in the grooves. When the cargo is a weighty article such as cereals, the rear surface part 5 partially swells out beyond the supporting bars as illustrated in Figures 3A and 3B and interferes with the closure of the doors 7 serving to shut the opening part 2.

At the time that the doors are to be opened, the inner pressure of the swell obstructs the doors from being unlocked and entails the possibility of causing the doors to burst open.

This swell of the bag could be eliminated by increasing the number of supporting bars. The supporting bars are generally made of a metallic material and, therefore, their cost accounts for a relatively large proportion of the total cost of the bag system. Since these supporting bars are used only during the transport of a granular or otherwise particulate cargo and are useless after completion of the transport and are cumbersome when the container is used for the transport of other kind of cargo, they are destined to be discarded in conjunction with the interior bag. The use of a large number supporting bars has effect of increasing the transport cost.The method of supporting the rear surface part of the interior bag by using the multiplicity of supporting bars has a disadvantage that, during the unloading of the cargo, the bars obstruct the flow of the cargo and renders difficult the work of unloading.

When the interior bag 4 is used in the generalpurpose container for transporting cereals, for example, the loading is generally effected by causing 10-odd tons of the cereals from a silo to be blown into the interior bag through a duct in a matter of several minutes (generally about 3 minutes). The unloading of this cargo is effected by a method which comprises opening the hinged door of the container 7, then forming an opening in the rear face part 5 of the bag by inserting a horizontal slit therein at a suitable position with a cutter, and subsequently tilting the container 1 itself together with the carrier vehicle backwardly thereby allowing the cereals to flow out all at once through the torn opening.

If a large number of supporting bars 3 were used for holding back the rear surface part of the interior bag, these bars would obstruct the selection of a position for the insertion of the slit restrain the torn opening to the extent of obstructing the flow of the cereals.

Besides the problem described above, the conventional interior bag entails the problem that when the torn opening is formed and the container is tilted backward to release the cargo, the interior bag slides backward in conjunction with the cargo and inflicts breakage upon the fastening devices attached to the container, particularly those attached to the lower end of the front face part, and the rear end of the bag out of the opening of the container and interferes with the flow of the cargo or, because of the slide, the bottom surface part of the bag forms furrows which catch hold of part of the cargo, interfere with the flow of the cargo, and prevent the cargo from being smoothly released.

This invention has been perfected by research and development conducted for the purpose of eliminating the problems encountered by the interior bag to be used when the general-purpose container intended primarily for the transport of ordinary kinds of cargo is appropriated to the transport of a granular and otherwise particulate cargo.An object of the invention is to provide a container interior bag capable of decreasing the number of supporting bars to be used for restraining the rear surface part of the bag proper from the swelling in the direction of the rear opening part of the container under the inner pressure due to the weight of the cargo thereby proportionately increasing the exposed surface area of the rear surface part and, at the same time, effectively curbing the swell of the rear surface part and enabling the hinged door or doors closing the opening of the container to be quickly and safely opened and shut.

This invention, in the light of the large addition to the cost of transport by the inevitable use of the plurality of supporting bars, aims to eliminate the impact of the increased cost of transport by decreasing the number of supporting bars and decrease the cost required in diverting the general-purpose container to the transport of a particulate cargo and simplify the work involved in the diversion.

A further object of this invention is to provide a container interior bag capable of smoothly releasing a bulk cargo by avoiding the otherwise possible breakage due to the slide of the bag when the container including the bag is tilted for the discharge of the contained cargo.

To accomplish the objects described above according to this invention, there is provided a container interior bag which comprises a bag proper of the shape of a substantial rectangular parallelepiped provided on the upper part of the rear surface part thereof with a cargo hopper and an insertion piece extended downwardly from at least the lower edge of the rear surface part of the bag and adapted to be inserted in a tense state beneath the bottom surface part of the bag proper.

The interior bag may be provided with an auxiliary sheet such as to cover the outer surface of the rear surface part of the interior bag throughout the entire width thereof below a level falling halfway along the height of the rear surface part, enclose the lower edge of the rear surface part, and extend enough for the lower end part of itself to be inserted along the bottom surface part of the bag proper. The portion of this auxiliary sheet, which extends below the lower edge of the rear surface part, can be used as the aformentioned insertion piece.

In accordance with the construction using this auxiliary sheet, before the granular or otherwise particulate cargo such as cereals is poured into the interior bag, the aforementioned insertion piece portion of the auxiliary sheet for tension is inserted beneath the bottom surface part to the extent of causing the auxiliary sheet to enclose the rear surface part as far as the lower edge thereof and causing the rear part of the bottom surface part to be drawn up. The portion contracted in length due to the drag is immobilized in conjunction with the insertion piece by the weight of the cargo introduced in the interior bag. When the rear surface of the interior bag swells under the inner pressure due to the weight to the cargo, the auxiliary sheet is stretched taut and enabled to prevent the swell from growing prominently.

In this construction of the auxiliary sheet, adhesive means capaable of keeping the insertion piece infallibly in the inserted state and, at the same time, facilitating the fixation of the amount of insertion may be disposed in the lower end part of the auxiliary sheet for tension and/or in the bottom surface part of the bag proper.

Further, the upper end of the auxiliary sheet for tension may be fastened to the rear surface part at a level falling halfway along the height of the rear surface part and, at the same time, the lower end part of the auxiliary sheet secured at a prescribed position on the bottom surface part so that the rear part of the bottom surface part may be contracted by a size prescribed as an allowance for the aforementioned drag.

The auxiliary sheet may be provided on the opposite sides in the roughly middle position thereof with stretching belts which, by being stretched and fastened to the lower end of the opening part of the container, enables the auxiliary sheet draped over the rear surface part of the bag to be kept desirably in a stretched state.

The interior bag may be further provided in the upper and lower corner parts of the front surface part thereof with stretching belts which, by being stretched taut inside the container, serve the purpose of preventing the bag from being snapped by the tension due to the slide of the bag.

As a result, the corners of the bag proper can be protected against possible breakage.

The tension exerted on the rear surface part of the bag may be effectively enhanced by causing the insertion piece to be extended not only in the downward direction below the rear surface part of the bag but also in the lateral directions beyond the opposite sides.

These extensions of the insertion piece may be formed by extending the auxiliary sheet laterally and downwardly or may be separately formed and fastened to the lower edge and the lateral edges of the rear surface part of the bag proper.

The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: Figure 1 is a partially cutaway perspective view illustrating an interior bag as used in a container for holding a bulk cargo; Figure 2 is a cross sectional side view schematically illustrating the container of Figure 1, with the rear doors opened and the bag consequently allowed to swell out; Figures 3A and 3B are respectively a cross sectional side view and a partial perspective view illustrating the prior art for preventing the swell of the interior bag; Figure 4 is a perspective view illustrating a interior bag as a first embodiment of this invention;; Figure 5 is a cross sectional side view illustrating the interior bag as fitted in a container for holding a bulk cargo; Figures 6A and 6B are cross sectional side views each schematically illustrating the essential part of the typical interior bag mentioned above as held for actual use; Figure 7 is a partial magnified perspective view illustrating supporting bars as fixed for actual use; Figure 8 is a perspective view illustrating another typical interior bag as a second embodiment of this invention; Figures 9A and 9B are respectively a rear view and a lateral cross section illustrating the bag of Figure 8 as disposed for actual use; Figure 10 is a perspective view illustrating a third embodiment of the interior bag according to this invention; Figure 11 is a developed view of the rear surface part of the interior bag of Figure 10;; Figure 12 is a cross sectional side view of the interior bag fitted in a container and filled with a bulk cargo; Figures 13A and 13B are respectively a lateral cross section and a horizontal cross section illustrating the rear surface part of the interior bag disposed for actual use; Figure 14 is a perspective view illustrating yet another typical interior bag as a fourth embodiment of this invention; Figure 15 is a developed view of the rear surface part of the interior bag of Figure 14; and Figure 16 is a horizontal cross section illustrating the rear surface part of the interior bag as disposed fast for actual use.

A first embodiment of the interior bag according to this invention will be descriped hereinafter with reference to Figures 4 to 7.

As illustrated, an interior bag proper 10 is formed in the shape of a rectangular parallelepiped fitting the inside dimentions of a container 1 and is provided at the four corners on the front surface part 10a thereof and at the two upper corners on the rear surface part 1Ob thereof with suspending cords 11 adapted to be caught fast on hooks (not shown) disposed in the inner corners of the container and to keep the bag proper in a cubically expanded state. The cords 11 are provided at the leading ends thereof each an annular hook lia. Optionally, curved hooks may be used instead of as illustrated in the drawings.

The bag proper is formed of a sheet of synthetic resin such as polyethylene, or some cloth similarly to the conventional interior bag, so that the surfaces thereof come into close contact with the inner wall surfaces of the container when the bag is fitted in the container with the aid of the suspending cords 11. The rear surface part of the bag opposed to the rear opening part of the container 1 has the upper part 10c thereof cut off a level falling halfway along the height of the rear surface part to form a cargo inlet 12. The rear surface part 1Ob below this level is prevented from rising upwardly by having the opposite edges thereof sewn to the rear edge parts of the opposite lateral surface part ford.

An auxiliary sheet 13 for tension formed in a roughly uniform breath throughout the entire length is sewn along the upper edge of the rear surface part 1Ob and is consequently suspended along the outer surface of the rear surface part.

The aforementioned auxiliary sheet 13 for tension is formed with a sheet longer than the height of the rear surface part 1Ob so that the lower end part of the auxiliary sheet in the suspended state extends below the lower edge of the rear surface part and gives rise to an insertion piece 13a.

The auxiliary sheet 13 inclusive of the insertion piece 13a encloses the rear surface part substantially entirely and the insertion piece 13a is inserted beneath the bottom surface part 10c. The auxiliary sheet 13 is provided along the upper edge part and at a level falling along the height thereof with tubular supporting bars 14 and 15 formed integrally with the sheet and laid in the horizontal direction. Further, the insertion piece 13a is provided on the inner surface thereof with adhesive tapes 17 attached fast as arranged in the direction of width of the insertion piece 13a so as to be freely attached to and detached from adhesive tapes 16 on the lower surface of the bottom surface part 10 of the bag proper.

The adhesive tapes 16, 17 are intended to establish fast union between the insertion piece 13 of the auxiliary sheet 12 and the bottom surface part 10e when the insertion piece 13a is inserted beneath the bottom surface 10e and prevent the auxiliary sheet from randomly slipping out and to serve as marks for determining favorably the allowance for the insertion of the insertion piece 13a.

In the present embodiment, the tapes are disposed either intermittently or continuously throughout the entire width of the pertinent parts.

Incidentally, in the present embodiment, the adhesive tapes 16 on the bottom surface part side are positioned slightly in excess of the length of the insertion piece 13a in the inserted state as illustrated in Figures 6A and 6B so that when the adhesive tape 17 of the insertion piece 13a joined thereto, the amount of this insertion of the insertion piece is increased and the rear part of the bottom surface part 10e is automatically drawn up inwardly and, as a result, the lower end of the rear surface part 1Ob is drawn inwardly (Figure 6B).

In one other embodiment of this invention, though not illustrated, the upper edge part of the auxiliary sheet 13 for tension to be draped on the rear surface part 1Ob of the bag proper may be sewn to the rear surface part and consequently attached integrally thereto and, at the same time, the insertion piece 13a suspended along the rear surface part may be drawn out under the bottom surface part 10c so as to pull the rear part of the bottom surface part forwardly and immobilize the insertion piece against the bottom surface part where the length is contracted, with the result that the auxiliary sheet causes a contraction of the length of the bottom surface part in the longitudinal direction of length and an inward drag of the lower end of the rear surface part 1Ob in concert with the contraction.

Since the interior bag of this invention is so constructed as described above, the use thereof is attained by first suspending the interior bag inside a given container with the aid of the suspending cords, then inserting the supporting bars in place, passing the opposite ends of the supporting bars 3 into the suspending rings 19 hung down from longitudinal frames erected upright on the laterally opposite of the opening part 2 of the container as illustrated in Figure 7, and suspending the supporting bars 3 at prescribed heights.

After the rear surface part 1Ob and the auxiliary sheet 13 have been suspended and supported in place at the positions by the fixation of the supporting bars, the insertion pieces 13a of the auxiliary sheet 13 is inserted beneath the bottom surface part 10e and, at the same time, the adhesive tapes are joined mutually. In this case, when the insertion piece 13a of the auxiliary sheet 13 fixed in place in advance as by being sewn to the stated position of the bottom surface part, the setting of the interior bag is completed by the work of suspension with the supporting bars.

After the interior bag has fitted closely inside the container as described above, the granular or otherwise particulate cargo such as cereals is stowed in the interior bag through the cargo inlet adapted to open toward the opening part of the container in the same manner as in the conventional interior bag.

When the cargo is piled inside the interior bag as the result of the loading described above, the weight of the cargo presses the bottom surface part 10e and, by this pressure, the insertion piece 13a of the auxiliary sheet inserted thereunder is pressed and consequently nipped between the interior bag and the floor surface of the container. The insertion piece thus nipped is prevented by the frictional force from being pulled out. As the piling of the cargo further advances until the weight of the cargo exerts inner pressure upon the rear surface part 1Ob, the auxiliary sheet whose insertion piece 13a is inserted beneath the interior bag is tensed so much as to prevent the rear surface part 1Ob from swelling out. As a result, the otherwise inevitable protrusion of the rear surface part in the direction of the opening part is precluded.

An interior bag measuring 5,800 mm in length, 2,300 mm in width, and 2,170 mm in height and provided with an auxiliary sheet of the description given above was tested to evaluate the effect of this invention. The results of the test indicate that interior bag fulfilled its effect sufficiently and the insertion piece produced sufficient frictional force when the insertion piece 13a was given a length of about 800 mm and that the interior bag was consequently allowed to keep its tense state without requiring any adhesive device and prevent the rear surface part 10b thereof from swelling out. In the test, the length of the rear surface part 10b was 1,800 mm and that of the upper surface part 10c was 900 mm.It was confirmed by the test that infallible retention of the insertion piece beneath the interior bag was obtained when the length thereof was approximately in the range of 500 to 1,000 mm.

Now, a working example of the interior bag of this invention will be described below. Generally, the loading of cereals are effected by a method of blowing which uses compressed air. In the case of a container having a loading capacity of 20 kilotons, it is normal for about 17 to 18 kilotons of the cereal to be loaded therein a matter of about 3 minutes.

The cargo blown into the bag by the compressed air brings to pile up from the leading end side of the inside of the interior bag and the pile continues to grow backwardly inside the interior bag until it reaches the rear part of the bag. The cargo consequently filling the bag presses the portion of the bottom surface part 10c contracted in length by the drag and participates in compressing and immobilizing the insertion part 13a of the auxiliary sheet 13. Then, the pile further grows finally to the extent of pressing the rear surface part 10(b).

In the interior bag of this embodiment, since the auxiliary sheet 13 draped over the outer surface of the rear surface part 10b is disposed as stretched taut in advance and is deprived of any allowance for further extension, and besides, since the rear surface part 1Ob of the bag urged by the pressure of the cargo presses the stretched auxiliary sheet and prevents it from producing a motion, the possible swell of the rear surface part 1Ob caused by the weight of the cargo is perfectly prevented.

Thus, the rear surface part is effectively prevented from protruding outwardly beyond the opening part 2 and interfering with the opening and shutting of the door 7.

From the interior bag of this invention in which the cargo has been loaded as described above, the cargo is unloaded by opening the door, then inserting a horizontal tear in the rear surface part 1Ob at a level close to the lower end thereof together with the auxiliary sheet 13 by the use of a cutter, and subsequently tilting the container proper backwardly thereby allowing the cargo to flow out of the container all at once by its own weight.

In this case, the collapse of the shape of the cargo due to the inclination of the container proper causes the interior bag to move backwardly. In the bag of this invention, since the lower corners of the opposite sides of the front surface 10a are fastened in place with elastic belts 11, the interior bag elongates proportionately to the slide of the bottom surface part 10e (as indicated by a two dot chain line in Figure 4) and absorbs the load exerted upon the fastening parts of the bag and, after the release of the cargo, contracts and returns to the home position and keeps the bottom surface part 10e in a flat state.As a result, the bag proper sustains no damage during the loading or unloading of the cargo and the bottom surface part of the bag proper retains no part of the cargo after the unloading because the bottom surface part is stretched out into a flat state in consequence of the decrease of the cargo. Thus, the cargo can be released quickly and smoothly. When the release of the cargo is effected by the inclination of the container, it often happens that the cargo remains more less on the bottom surface part. In this case, workers engaging in the unloading are compelled to remove the remaining cargo by shaking the bottom surface part 10e.

In the case of the interior bag of this invention, this removal of the trapped cargo by shaking is attained easily because the bag proper is fastened in place with the elastic belts 11. And the shaking be efficiently carried out because the expansion of the belts permits a slight longitudinal movement of the bottom surface part.

In this invention, when the elastic belts serving to keep the front end part of the bag proper in place is slid backward in conjunction with the cargo owing to the inclination of the container, the heavy burden exerted upon the parts keeping the bag fast is absorbed by the elongation of the elastic belts. Unlike the conventional interior bag, therefore, the belts are not snapped or the bag itself is not broken under the large burden mentioned above. When the unloading of the cargo advances, the particulate cargo is not trapped inside the interior bag but is discharged smoothly because the bag is allowed to resume its original shape and the bottom surface part of the bag is enabled to resume its original flat shape by the contracting force of the belts. The fact contributes much to the enhancement of operational efficiency of the unloading.

In the case of a cargo which is not readily allowed to flow out by the inclination of the container, the fact that the bottom surface part is allowed to resume its flat shape by the contraction of the belts proves to be convenient because the work of shaking the bag can be carried out very simply as a consequence.

In accordance with this invention, the rear surface part can be prevented from swelling out and the necessity for using many supporting bars can be obviated owing to the stretching force of the auxiliary sheet 13 provided with the insertion piece 13a as described above. As a natural consequence, the work of opening and shutting the hinged doors of the container can be facilitated and the interior bag is not suffered to exert a strong inner pressure upon the doors and the otherwise inevitable possibility of the doors being burst open can be precluded. Thus, the doors can be opened and shut quickly and safely.

Then, the decrease in the number of supporting bars to be used for the interior bag results in a reduction in the cost of transport and a proportionate addition to the area of the rear surface part left open and accordingly facilitates the selection of a position in the rear surface part for the formation of an opening by the insertion piece of a tear with a cutter at the time of unloading of the cargo. Moreover, the size of this opening is allowed to be simply large. Further, the decrease in the number of supporting bars results in facilitating the work of fitting the opposite end parts of the supporting bars in the grooves of the vertical frames.

Consequently, the work of fitting the interior bag in the container can be easily and quickly carried out.

In another typical interior bag as the second embodiment illustrated in Figures 8 and 9, the rear surface part is enabled to produce a more effective tense state by attaching a stretching belt 21 provided at the leading end thereof with hooks 22 to the auxiliary sheet 13 at a level falling halfway along the height thereof in addition to making use of the stretching action exerted by the insertion piece 13a upon the rear surface part of the bag. In short, the rear surface part of the bag is given a desirable tense state by setting the hooks 22 fast on supports 23 disposed in the lower corners of the rear ends of the lateral walls la of the container.

In the diagrams, the reference numerals which have equivalents in the diagrams of the embodiment mentioned above denote identical or equal component parts. The description of these component parts is omitted below to avoid repetition.

In the illustrated embodiment, a pair of stretching belts 21 for exerting tension upon the auxiliary sheet 13 are symmetrically disposed as opposed to each other.

Optionally, a plurality of such stretching belts may be disposed on each of the lateral sides. Of course it is otherwise permissible to dispose these stretching belts along the center between the opposite sides and allow them to stretch the auxiliary sheet by being set fast against the lower edge of the opening part directly below.

Particularly the embodiment having such stretching belts disposed one each on the lateral sides so as to be elongated in downwardly diverging directions is aimed at efficiently enhancing the effect of stretching in addition to simplifying the construction as a whole.

It is clear from the embodiments noted above that since this invention consists essentially in effectively stretching the rear surface part of the interior bag by the action of the insertion piece, the tension of the rear surface part of the bag can be attained more effectively by integrally extending from the opposite lateral edges of the auxiliary sheet 13 such insertion pieces 13b adapted to be inserted between the lateral surface parts lOd of the bag and the lateral walls la of the container as illustrated in Figures 10 to 13 in addition to resorting to the insertion pieces 13a adapted to be inserted beneath the bottom surface part 10e of the bag.

In this third embodiment, the interior bag 10 loaded with the cargo bears the weight of the cargo on the bottom surface part 10e thereof and this weight presses the lower insertion piece 13a inserted thereunder against the bottom surface of the container and consequently fixes this insertion piece 13a between the bag and the container.

Since the area of application of this pressure expands laterally with the advance of the loading of cargo, the same fixing action as mentioned above has its effects to bear on the lateral insertion pieces 13b which are along the outer lateral surfaces of the lateral surface parts, with the result that the opposite insertion pieces are immobilized in the inserted state.

When the insertion pieces 13a, 13b mentioned above are set fast in place as draped on the lower surface part 10a and the lateral surface parts lOd of the bag and nipped between the surface parts 10e and the wall surfaces 10 la of the container, the insertion pieces 13b may be provided with fastening devices 25 and tacked to the lateral surface parts of the bag by setting these fastening devices 25 to the fastening devices disposed in advance on the lateral surface parts.

When the cargo accidentally exerts an inner pressure on the rear surface part, for example, these insertion pieces 13a, 13b readily cancel the fastened state and prevent the bag proper from sustaining breakage. Of course, these fastening parts are adapted to be readily broken under the impact of the accidentally exerted inner pressure when the free edges of these insertion pieces are immobilized in advance as by fastening, for example.

An interior bag of this embodiment was produced for in a 20-ton general-purpose container by preparing a bag proper measuring 5,800 mm in length, 2,300 mm in width, and 2,170 mm in height and attaching the insertion pieces 13a, 13b both of a length of 100 mm to the bag proper.

This interior bag was put to use, with the insertion pieces inserted to a length of 200 mm, for the transport of cereals. The rear surface part was infallibly prevented from swelling out and was not suffered to protrude to the extent of impinging on the hinged doors serving to keep the rear opening of the container shut.

In the aforenoted third embodiment, the insertion pieces 13a, 13b were integrally formed with the auxiliary sheet 13 so as to assume an approximate shape or the letter T as illustrated in the developed diagram of Figure 11. Optionally, these insertion pieces may be formed independently of one another and attached as draped over the lower edge and the opposite lateral edge of the rear surface part 10b of the bag as in the fourth embodiment illustrated in Figures 14 to 16.

To be specific, the lower insertion piece 13a is attached fast to the lower edge of the rear surface part 1Ob of the bag and the lateral insertion pieces 13b attached fast one each to the opposite lateral edges of the rear surface part 1Ob of the bag.

In this embodiment, the lateral insertion pieces 13b are formed each in a substantially trapezoid shape. It is of course permissible to form in a rectangular shape similarly to the lower insertion piece 13a or in some other shape selected freely.

The present embodiment can be expected to bring about the same effect as the embodiment described above in spite of the omission of the auxiliary sheet. In this embodiment, the lower and lateral insertion pieces 13a, 13b are jointly used. For the attainment of the effect equivalent to that of the first embodiment, only the insertion piece 13a may be used.

In the embodiments described above, like reference numerals denote like or otherwise equal component parts.

In accordance with this invention, the rear surface part of the bag proper is reinforced and prevented from swelling out by the tension produced in the auxiliary sheet immobilized by the pressure of the weight of the cargo. Thus, the hinged doors of the container can be closed easily and safely after the loading of cargo in the container is completed and the doors can be shut similarly easily and safely at the time of unloading of the cargo.

Further, since the interior bag of this invention has no use for the supporting bars otherwise required to be passed across the rear surface part at least below a level halfway along the height thereof, the position for the insertion of a tear with a cutter can be selected with ample freedom and the tear itself can be formed in an amply large size.

Moreover, the invention is advantageous in respect that the consumption of supporting bars is generously and the cost of transport is proportionately decreased. It also enjoys an advantage that the work of using the interior bag in the container is notably alleviated because the work of fitting the interior bag in the container is simplified.

Claims

1. An interior bag to be fitted in a container, which interior bag comprises a bag proper of the shape of a rectangular parallelepided provided with a front surface part, a rear surface part provided in the upper part with a cargo inlet, lateral surface parts, a bottom surface part, and an insertion piece extended below the lower edge of said rear surface part said insertion piece being adapted to be inserted between the lower surface of said bottom surface part of said bag proper and the bottom surface of said container.

2. An interior bag according to claim 1, further comprising an auxiliary sheet having its upper edge thereof attached to the rear surface part of said bag at a level below said cargo inlet of said rear surface part with the portion of said auxiliary sheet protruding from the lower edge of said rear surface part of said bag which portion is diverted as said insertion piece.

3. An interior bag according to claim 2, further comprising a tubular supporting bar fitting part disposed in the upper edge part of said auxiliary sheet and a supporting bar inserted in and set inside said supporting bar fitting part.

4. An interior bag according to claim 2, further comprising a second tubular supporting bar fitting part disposed substantially in the middle of said auxiliary sheet and a supporting bar inserted in and set fast inside said second supporting bar fitting part.

5. An interior bag according to claim 3 or claim 4, wherein said supporting bar fitting part is joined to the upper edge of said rear surface part of said bag proper.

6. An interior bag according to any of claims 1 to 5, further comprising adhesive tapes disposed in the lower end of said insertion piece or on the bottom surface part of said bag.

7. An interior bag according to any of claims 1 to 6, further comprising suspending cords provided at the leading ends thereof with a hook and disposed in the four corners of said front surface part of said bag and two upper corners of said rear surface part of said bag and adapted to be suspended inside said container.

8. An interior bag according to any of claims 1 to 7, further comprising stretching belts provided at the leading ends thereof with a hook, attached to said auxiliary sheet at a level falling halfway along the height thereof and adapted to be fastened to supports disposed in the lower corners of the rear end of said inner wall of the container.

9. An interior bag according to any of claims 1 to 8, further comprising lateral insertion pieces extended from the lateral edges of said rear surface part and adapted to be inserted between the lateral surface parts of said bag proper and the lateral surface of said container.

10. An interior bag according to claim 3, further comprising lateral insertion pieces formed integrally as extended from the opposite lateral edge of said auxiliary sheet.

11. An interior bag according to claim 1, further comprising an insertion piece integrally formed at the lower edge of said rear surface part.

12. An interior bag according to claim 11, further comprising lateral insertion pieces integrally formed along the lateral edge said rear surface part.

13. An interior bag according to any of claims 9 to 12, wherein adhesive tapes are disposed at the leading end of said lateral insertion pieces and/or in the lateral surface parts of sa:'d bag.

14. An interior bag substantially as herein described with reference to Figures 4 to 7, Figures 8, 9A and 9B, Figures 10 to 13A and 13B, or Figures 14 to 16 of the accompanying drawings.