Container

Abstract

A container with a lifting device for raising the bottom of the container includes a lifting cushion which is expandable by internal fluid pressure. The cushion is expandable only with respect to its height. The cushion includes a plurality of congruent horizontal walls which are forming chambers arranged one above the other and vertical walls connecting the horizontal walls. In the pressureless state of the cushion, the vertical walls are folded inwardly.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a container with a lifting device for raising the bottom of the container.

2. Description of the Related Art

Containers of the above-described type are known, for example, from DE 199 48 940 A1 and DE 101 42 368 A1. These containers have the advantage that, by raising the bottom it is possible independently of the degree by which the container is filled, objects stored in the container, for example, articles offered for sale, can be kept always at such a level that they can be easily reached. In these conventional containers, springs or motor-driven scissors-type lifting devices are used as lifting devices.

SUMMARY OF THE INVENTION

It is the primary object of the present invention to simplify the construction of the lifting device of the container of the above-described type.

In accordance with the present invention, this object is met by a lifting device which includes a cushion which is expandable by internal fluid pressure.

A cushion of this type may be a lifting cushion which is adjustable essentially only with respect to its height, wherein the cushion expands in the vertical projection almost over the entire container bottom without making contact with the side walls of the container when the cushion is expanded.

In accordance with a preferred embodiment, the lifting cushion advantageously has three horizontal walls which are congruent as seen from above and form several chambers arranged one above the other. Sidewalls are provided for connecting the horizontal walls at the edges thereof, wherein the side walls are folded inwardly when the cushion is not under pressure. Such a lifting cushion with additional critical intermediate walls in the chambers which are arranged one above the other maintains its square shape during expansion and only changes its height. As seen from above, the cushion can essentially fill out a parallelipiped-shaped container interior.

In accordance with a preferred embodiment of the invention, the container includes a pallet and the cushion is releasably or non-releasably connected to the pallet.

The side walls of the container may be releasably connected to the pallet. As a result, a pallet with cushion can be advantageously used over a long period of time by exchanging the sidewalls which wear more quickly.

In accordance with an advantageous feature, the sidewalls of the container which are connected to each other and can be folded can be pushed onto the pallet when they are in the folded-out state.

In accordance with another advantageous embodiment of the invention, a pump is provided for filling the cushion with the fluid as well as for drawing off the fluid from the cushion. Compressed air is preferably used as fluid. Air can be taken in without problems from the atmosphere and can be discharged to the atmosphere.

In accordance with another advantageous feature, a pump for conveying the fluid is mounted immediately at the container and is integrated, for example, in the pallet where it is accommodated, for example, in a leg.

The bottom of the container may be formed by the uppermost horizontal wall of the cushion or a separate bottom wall arranged on the cushion.

The uppermost horizontal wall and/or the separate bottom wall may have a sealing lip which extends around the edge and rests against he sidewalls of the container. The sealing lip prevents the contents of the container from dropping down between the edge of the bottom wall and the sidewalls.

Preferably, a check valve is provided for maintaining the internal pressure of the cushion. The pump then only has to compensate for leakage losses.

A measuring device which scans the surface of the contents of the goods filled in the container can control the pump in such a way that it is switched on as soon as the measured filling level drops below a predetermined value.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing:

FIG. 1 is a cross-sectional view of a pressure cushion used in a container according to the present invention, wherein the cushion is in the folded state;

FIG. 2 is a cross-sectional view of a pressure cushion used in a container according to the present invention, wherein the cushion is in the expanded state;

FIG. 3 is a schematic view of a container according to the present invention with a pressure cushion similar to that shown in FIGS. 1 and 2;

FIG. 4 is a schematic view of the container of FIG. 3 with the pressure cushion in the expanded condition; and

FIG. 5 is a schematic view of a device for applying pressure to the cushion which can be used in a container according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the embodiment of the invention illustrated in FIGS. 1 and 2, a pressure cushion includes six congruent rectangular horizontal walls 1 and vertical sidewalls 2 which connect the horizontal walls to each other. As can be seen in FIG. 1, the sidewalls 2 are folded inwardly when the cushion is in the pressureless state.

The horizontal walls 1 are additionally connected to each other through two vertical intermediate walls 3. In the pressureless state of the cushion, the intermediate walls 3 are also folded inwardly toward the middle of the cushion. While the horizontal walls form together with the sidewalls 2 chambers which are arranged above each other, these chambers are further divided by intermediate walls 3 into compartments which are located horizontally next to each other. The sidewalls 2 and the intermediate walls 3 are more flexible than the horizontal walls 1. It is understood that the chambers and compartments are in communication with each other through openings, not shown.

As illustrated in FIG. 2, the cushion can be expanded by admitting compressed air to the cushion. The sidewalls 2 and the intermediate walls 3 ensure that the cushion essentially only changes its height but not its width, when compressed air is admitted, and that the cushion maintains its parallelepiped shape.

In a deviation from the embodiment shown in FIGS. 1 and 2, the number of horizontal and intermediate walls may be larger or smaller.

The parallelepiped shaped container shown in FIG. 3 includes a pallet 4 with legs 5. The pallet manufactured from synthetic material is connected to a pressure cushion similar to that illustrated in FIGS. 1 and 2. The pressure cushion 6 is placed in a recess 7 of the pallet and is glued to the pallet. This lifting cushion is constructed so as to only change its height.

An impact edge 8 is formed circumferentially on the pallet adjacent the recess 7, wherein the four sidewalls 9 of the container rest on the impact edge 8. The pressure cushion 6 which extends upwardly beyond the impact edge 8 forms together with the impact edge a seat for the foldable sidewalls 9 which are connected to each other, so that the folded up sidewalls can be pushed onto the pallet.

Arranged on the lifting cushion 6 is a bottom wall 11 which forms the bottom of a container interior 10, wherein the bottom wall 11 is approximately congruent with the horizontal walls 1′ of the cushion 6 and has at its edge a circumferential sealing lip 12 which rests against the four sidewalls 9.

As can be seen from a comparison of FIGS. 3 and 4, the bottom wall 11 can be raised by expanding the pressure cushion 6 and, for example, goods 13 offered for sale can be presented in the container at always a comfortably reachable level independently of the filling state of the container.

A pump 14 shown in FIG. 5 serves for applying pressure to the lifting cushion 6. The pump 14 is connected through a valve 15 to the pressure cushion 6 and can be connected to a power source through a switching device 16.

The switching device 16 can be actuated optionally either manually, for example, through a foot switch, or can be actuated by a sensor 18 which monitors the filling state of the container. The sensor 18 may be, for example, a light barrier or an optical scanner. When the sensor recognizes a filling state which is too low, it actuates the pump 14 through the switching device 16, so that the pump 14 increases the pressure in the cushion 6 and, thus, raises the bottom wall 11 further. When the desired filling level is achieved, the sensor 18 once again switches off the pump 14 through the switching device 16.

The valve 15 is an electromagnetic two-way valve which includes a check valve in a first valve path, so that the pressure achieved in the cushion 6 is always essentially maintained.

For quickly emptying the pressure cushion 6, the valve 15 is switched through the switching device 16 to the second valve path and the pump 14 is switched to suction operation.

The devices 14, 15, 16 and 19 surrounded by a broken line 20 in FIG. 5 are combined in a structural unit which is accommodated in one of the legs of the pallet 4. For this purpose, an electric outlet is provided in one of the legs 4, as illustrated in FIGS. 3 and 4.

While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

1. A container comprising a bottom and a lifting device for raising the bottom, the lifting device comprising a cushion expandable by internal fluid pressure.

2. The claim according to claim 1, wherein the cushion is a lifting cushion, wherein essentially only a height of the lifting cushion is changeable.

3. The container according to claim 2, wherein the cushion comprises a plurality of congruent horizontal walls for forming a plurality of chambers arranged one above the other, further comprising vertical walls connecting the horizontal walls.

4. The container according to claim 3, wherein the vertical walls are folded inwardly in a pressureless state of the cushion.

5. The container according to claim 1, wherein the container comprises a pallet, wherein the cushion is connected releasably or unreleasably to the pallet.

6. The container according to claim 5, wherein sidewalls of the container are releasably connected to the pallet.

7. The container according to claim 6, wherein the side walls are configured to be pushed onto the pallet.

8. The container according to claim 1, wherein the cushion in a vertical projection thereof essentially fills out an entire interior of the container.

9. The claim according to claim 1, further comprising a pump for filling the cushion with the fluid and for withdrawing fluid from the cushion.

10. The container according to claim 9, wherein the container is in communication with the pump for conveying the fluid.

11. The container according to claim 10, wherein the pump is mounted in a leg of the pallet.

12. The container according to claim 3, wherein the bottom of the container is formed by an uppermost of the horizontal walls of the cushion.

13. The container according to claim 3, wherein the bottom of the container is formed by a separate bottom wall arranged on the cushion.

14. The container according to claim 12, the uppermost horizontal wall has a sealing lip resting against the sidewalls of the container.

15. The container according to claim 13, wherein the separate bottom wall has a sealing lip resting against the sidewalls of the container.

16. The container according to claim 14, wherein the pump is connected to the cushion through a check valve for maintaining the achieved internal pressure.