IL106823A - Bottom-unloading bulk container - Google Patents

Description

m>nnn i pimn mi ran i?D>n Bottom-unloading bulk container NISIM SABAN C: 90962/2 BOTTOM-UNLOADING BULK CONTAINER FIELD OF THE INVENTION The present invention concerns a so called " bottom-unloading bulk container", i.e., a container having special means for dumping its contents. More particularly, the invention provides a container transportable by conventional machines, such as a crane, a forklift truck or the like, and which can be automatically unloaded from the bottom by the same machine at a desired unloading site.

BACKGROUND OF THE INVENTION Several kinds of bottom-unloading containers having various mechanisms for opening and closing their bottom or a lower part of their walls, are known in the art.

US patent 4,210,273 describes a bottom-unloading container having a bottom closure and a top closure each including flaps hinged to the side walls. Openings in the side walls are proportioned to receive the tines of a forklift truck. Bands encircle the body and the top and bottom closures. The filled container can be lifted and transported to an unloading location by a forklift truck, and its contents dumped through the bottom opening upon manual release of the encircling bands.

SU patent 1611810 discloses a rectangular container having a bottom consisting of two hinged flaps. The flaps are retained in the closed position by a pair of pivoted crank catches on opposite sides of the container. The catches are linked to a lifting traverse associated with a handle. With the manual rotation of the handle from the "open" to the "closed" position, a specific rather complex mechanism causes the pivoted crank catches to engage stops provided on the hinged flaps of the container's bottom. A counter-balance weight on the lifting traverse maintains it in the normally "closed" position.

SU 1395561 relates to a transport container, the bottom of which is formed by two hinged flaps, which are connected by links to a pair of vertical slide rods mounted on vertical guides on opposite walls of the container. The flaps are retained in the closed position by engagement the slide rods with corresponding hooks releasable by a manually operable handle.

WO 93/04953 describes a container adapted to be unloaded inside a stationary base frame. The bottom of the container is pivotally connected to its body and is supported by the base frame. Specific latching means are provided for locking the bottom of the container in its closed position. The container base can also have abutment means for enabling a top lift machine to raise the container and allow the bottom to open.

However, all the containers described above can be opened and closed either manually (US 4,210,273, SU 1611810, 1395561), or by some mechanical operation (WO 93/04953) only when being in a rest position. In other words, the last mentioned container is not adapted at all for transportation when loaded, whereas other above mentioned containers, although being transportable when loaded, can only be opened or closed manually.

Therefore, none of these known containers can be used for transporting a bulk load and automatic unloading it when positioned above a predetermined site, e.g., a floor of a building under construction. Moreover, an additional manual operation is needed for reclosing the emptied container.

OBJECT OF THE INVENTION It is therefore the object of the present invention to provide a transportable bottom unloading container adapted to be opened and closed automatically by a conventional lifting machine which is also used for its transportation.

SUMMARY OF THE INVENTION The abovementioned object is achieved by the present invention which provides a rectangular bottom-unloading container of the type comprising side walls, a bottom consisting of a pair of rectangular flaps hingedly connected, respectively, to the lower edges of a first pair of opposite side walls, characterized in that a pair of horizontal bars are provided external to a second pair of opposite side walls having outwardly extending flanges along their upper edges; said horizontal bars being vertically displacable, respectively, along said second pair of side walls between a lowermost and an uppermost positions; each of said horizontal bars cooperating via a linking means with both said flaps, so as to open them when said horizontal bars are in their lowermost position, and to close them when said horizontal bars are in their uppermost position; the vertical displacement of said horizontal bars being caused by a lifting machine (such as a crane, forklift, or the like).

In accordance with a preferred embodiment of the invention each of said linking means consists of a pair of rods, each being hinged at its upper end to the middle region of the bar and at its lower end to the side edge of the corresponding flap.

The flanges provided at the upper edges of at least one pair of opposite side walls of the container should project beyond the outer surface of said horizontal bars.

The four vertical corners of the container may preferably be reinforced by uprights e.g., angle profiles. In this case each of the horizontal bars may be engaged by a respective pair of said uprights in a manner allowing its vertical displacement along said uprights.

In accordance with an alternative embodiment of the invention said horizontal bars may be connected to each other at their ends by another pair of horizontal bars, thus forming together with them a rectangular frame vertically slidable along the four sides of said container. This embodiment has the advantage that the clamp of a lifting machine can engage also these additional horizontal bars.

The outwardly extending flanges may be provided also at upper edges of said first pair of the side walls of the container. The bottom periphery of the container may be optionally provided with a horizontally extending rim.

The container according to the invention can be transported and automatically unloaded most effectively by a hydraulically or pneumatically operated clamp of a lifting machine such as a crane. In the context of this application the term "clamp" should be understood to refer to a gripping device capable to contract and expand. When the closed and loaded container according to the invention is to be transported for unloading above a desired site, the clamp of the lifting machine is contracted onto said pair of the horizontal bars, pressing them against the corresponding side walls of the container. Alternatively, the clamp may be contracted so as to grip and support the bars from beneath. In both cases the bars are retained in their uppermost position, thus preventing the bottom of the container from opening. The container may then be transported by the lifting machine to the predetermined site, and while the container is still suspended in the air, the clamp is slightly expanded just enough to release said horizontal bars, but still leaving a sufficiently narrow gap so as to retain and hold the container by the upper flanges of the side walls. It will be understood, that in the course of this operation the container slips down slightly, but, as stated above, is retained in said clamp by the flanges at its top. Once the horizontal bars are released from the clamp, the flaps are opened by gravity causing said rods to pull the horizontal bars downwards to their lowermost position.

The clamp of a lifting machine to be used in conjunction with a container according to the invention, should be preferably fitted with a pair of horizontal splints adapted to safely engage and hold said horizontal bars. Said splints may be provided with longitudinal grooves on their inner surfaces, in order to further improve their grip on the outer surfaces of the bars.

The container according to the invention can also be transported and unloaded by a conventional forklift truck, having a vertically displacable fork. In this case the fork first engages the pair of the horizontal bars (e.g., from beneath), the container can be then transported in a regular manner by the fork lift to the desired site. The container is then lowered to the ground; the fork is then retracted to disengage from the horizontal bars and advanced again so as to engage the top flanges of the container. When the container is then raised by the forklift, the bottom will be automatically opened to unload the container.

The outer surfaces of the bottom flaps may be optionally provided with a plurality of vertical supports so as to form a pallet when the flaps are in the closed position, thus enabling the container to be lifted from beneath by the forklift truck.

The container according to the invention may be also modified so as to be capable of unloading by a crane having a regular hook. To this end, the container is additionally provided with a pair (or two sets) of rings. A first ring (or set of rings) is bound (e.g. by chains) to the horizontal bars, and the second ring (or set of rings) is fixedly attached to the top of the container. During transportation the hook of the crane engages the first ring (or set) so as to retain the horizontal bars in their uppermost position. When the container is to be unloaded, it is placed on the ground, and the hook of the crane must be manually disengaged from the first ring (or set) and made to engage the second ring (or set), whereby the container can be lifted to unload by gravity.

An important advantage of the container according to the invention resides in that after unloading its bottom may be reclosed by the same lifting machine, which was used for transportation and unloading of the container.

To this end the container is placed on the ground, the horizontal bars are be raised to their uppermost position by any of the above mentioned means (e.g. a clamp, a fork or a hook) thus pulling up the rods and securing the bottom flaps in the closed position.

The container according to the invention is, as a rule, closed at all its four sides and is loadable from its open top. However, one or two opposite sides of the container may be open (i.e. the side walls are absent), allowing such container to be loaded from one or both sides. Such a construction is especially suitable for loading bulky objects such as sacks or the like. In this embodiment of the invention the bottom has a peripheral rim (such as mentioned above), and the flaps are hinged to this rim at the opposite sides of the container.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention will be further illustrated by the aid of the attached non-limiting drawings, wherein: Fig. 1 is a perspective view of a container according to this embodiment, when placed on the ground in its closed position; Fig. 2 is a perspective view of the container of Fig. l in its closed position (shown in dotted lines) when lifted by a hydraulic clamp of a crane, and when opened (shown in solid lines) while in the air, by the same clamp; and Fig. 3 is a perspective view of the container of Fig.l when placed on the ground in its opened position, showing also the clamp of the crane in its position under the horizontal bars.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Fig. 1 shows a rectangular container generally referenced 10, the bottom of which consists of a pair of flaps 14 hinged, respectively, to the lower edges of a first pair of opposite side walls 12. The upper edges of the walls 12 and of the second pair of opposite side walls 16 are provided with outwardly extending flanges 17. A pair of horizontal bars 18 (only one seen in Fig. 1) are engaged by uprights 20 of the container and are vertically slidable along them. Each bar 18 is connected to both flaps 14 via a pair of pivoted rods 22, so as to close and open the flaps when the bar 18 is displaced up and down, respectively. In Fig. 1 the horizontal bars 18 are shown in their uppermost position and the flaps 14 are closed. A clamp 24 of a crane is situated above the container. The clamp 24 is provided with a pair of longitudinal splints 26 adapted to engage the bars 18. The splints 26 have grooves on their contact surfaces for better friction with elements of the container during operation.

Fig. 2 demonstrates the process of unloading of the container 10 while suspended in the air, by means of the hydraulically operated clamp 24 of a crane. The dotted lines show the container 10 in its closed position when lifted by the clamp 24, and the splints 26 being contracted onto the horizontal bars 18. For illustrative purposes the distance of the horizontal bar 18 and the splint 26 holding it (as shown in the dotted lines) from the flange 17 is largely exaggerated and also, the horizontal bar 18 and the splint 26 are shown somewhat displaced in respect of each other, so as to expose the bar 18 behind the splint 26. In actual operation, the bar 18 abutts against the flange 17 (as in Fig. 1) and would have been consealed by the splint 26. When the clamp 24 is slightly expanded by means of a slight automatic release of the hydraulic pressure (which is actuated remotely by a crane worker), it releases its hold on the horizontal bar 18, but the container 10 is now retained in the clamp 24 by the flanges 17, which project horizontally beyond the outer surfaces of the bars 18. The bottom flaps 14 which are not longer held up by the rods 22 being associated with the now released horizontal bars 18, are opened by the weight of the contents of the container. Thereby the flaps 14 pull down the rods 22, which in turn pull the bars 18 down to their lowermost position. The unloaded open position of the container 10 retained by the clamp 24 is shown in solid lines.

Fig. 3 shows the unloaded open container 10, after it is lowered to the ground and after the splints 26 of the clamp 24 are introduced under the horizontal bars 18 in order to reclose the container by the upward pull of the clamp 24.

Claims (8)

CLAIMS:

1. A rectangular bottom-unloading container of the type comprising side walls, a bottom consisting of a pair of rectangular flaps hingedly connected, respectively, to the lower edges of a first pair of opposite side walls, characterized in that a pair of horizontal bars are provided external to a second pair of opposite side walls having at their upper edges flanges projecting outwardly beyond the outer surfaces of said horizontal bars; said horizontal bars being vertically displacable, respectively, along said second pair of side walls between a lowermost and an uppermost positions; each of said horizontal bars cooperating via a linking means with both said flaps, so as to open them when said horizontal bars are in their lowermost position, and to close them when said horizontal bars are in their uppermost position; the vertical displacement of said horizontal bars being effected by a lifting machine.

2. A container in accordance with Claim 1, wherein each of said linking means consists of a pair of rods, hinged at their upper ends to the middle region of the bar and at lower ends to a side edge of a corresponding flap.

3. A container according to any one of the preceding claims, wherein the four vertical corners of the container are reinforced by uprights; each said horizontal bar being engaged by a respective pair of said uprights in a manner allowing its vertical displacement along said uprights.

4. A container according to Claim 1 or 2, wherein said horizontal bars are connected to each other at their ends by another pair of horizontal bars, thus forming together with them a rectangular frame vertically slidable along the four sides of said container. 106823/2 - 10 -

5. A container according to any one of the preceding claims, wherein said flanges are provided at the upper edges of all the side walls of the container.

6. A container according to any one of the preceding claims, wherein the outer surfaces of the bottom flaps are provided with a plurality of vertical supports so as to form a pallet when the flaps are in the closed position, thus enabling the container to be lifted from beneath by the forklift truck.

7. A container according to any one of the preceding claims, adapted to be unloaded also by a crane having a hook, said container being additionally provided with at least two rings; the first ring being joumalled to the horizontal bars, and the second ring being fixedly attached to the top of the container.

8. A rectangular bottom-unloading container comprising at least two opposite side walls having outwardly extending flanges along their upper edges, a bottom consisting of a peripheral rim and a pair of rectangular flaps hingedly connected, respectively, to opposite sides of said peripheral rim; the container further comprising a pair of horizontal bars external to a pair of opposite side walls and vertically displacable along them between a lowermost and an uppermost positions; each of said horizontal bars cooperating via a linking means with both said flaps, so as to open them when said horizontal bars are in their lowermost position, and to close them when said horizontal bars are in their uppermost position; the vertical displacement of said horizontal bars being caused by a lifting machine. For the Applicants, DR. REINHOLD COH AND PARTNERS