The invention relates to a clamp for closing a round and/or flat ballast hose.

It is known to provide a silo for the purpose of ensiling fodder such as grass or silage maize. Such a silo is a concrete construction with a floor and upright walls along two or three sides. In this silo the fodder is stored and firmly pressed, for instance by driving a tractor or power shovel thereover. The pile of fodder in the silo is then covered with one or more layers of plastic sheeting. Finally, the sheeting is weighted to prevent it being blown away. This weighting can take place by means of old car tyres or soil or sand, optionally packaged in bags.

For the purpose of weighting the layers of plastic sheeting it is further known to place on the sheeting a flat ballast hose filled with a liquid such as water. When the sheeting has to be removed from the pile of fodder, the hose is drained and the hose can be wound onto a reel.

Once fodder has been taken from the pile in the silo, the sheeting is re-placed and the hoses are once again placed on the sheeting and filled with liquid.

The covering of long silos is labour-intensive.

It is now an object of the invention to reduce or even obviate the above stated drawbacks.

This object is achieved with a clamp according to the preamble, the clamp comprising:

- a frame;

- a first elongate clamping surface arranged fixedly in the frame;

- a second elongate clamping surface arranged movably in the frame such that the second clamping surface can be moved to the first clamping surface; and

- clamping means for urging the second clamping surface to the first clamping surface.

It is possible with the clamp to divide a liquid-filled round and/or flat ballast hose into compartments by clamping the hose shut at a determined position along the hose by means of a clamp. Only a part of the hose need hereby be emptied in order to remove the sheeting from the fodder. After removing a part of the fodder in the silo the sheeting can then be re-placed while a part of the hose remains filled with liquid.

Flat ballast hoses are used during ensilage. These hoses are often formed from reinforced fabric and are flat in empty state, whereby great lengths can be easily wound onto a reel. When a flat ballast hose is filled with liquid, it will bulge outward and become more or less cylindrical in shape.

In order to enable reliable closing of such a filled hose it is necessary for elongate clamping surfaces to be provided, between which the hoses can be pressed flat. It is important here that sufficient clamping force is generated along the whole length of the elongate clamping surfaces.

In a preferred embodiment of the clamp according to the invention the first clamping surface is formed by two rollers arranged parallel against each other. Owing to the cylindrical surface a roller provides a line contact, while the chance of damaging the hose is minimal. This in contrast to for instance an edge of a square tube. In addition, a roller has a high bending stiffness, so that a high clamping force can be obtained.

The second clamping surface is preferably also formed by at least one roller. This one roller can then fall between the two parallel rollers of the first clamping surface, whereby two line contacts are created and a double closure is obtained.

In a preferred embodiment of the clamp according to the invention the surface of a roller is provided with a resilient layer. Using this resilient layer irregularities such as small stones or sand can be compensated for without these irregularities possibly causing tears in the hose. If the surfaces are hard it is possible that for instance a small stone is pressed into the hose during clamping, thus forming a leak. Through the use of a resilient layer the irregularities can also be pressed at least partially into this resilient layer. Imbalances caused by tightening of the hose can also be compensated by this resilient layer .

In another preferred embodiment the clamping means comprise two threaded ends arranged on either side of the first clamping surface, and two nut parts, each arranged on the threaded ends, wherein the second elongate clamping surface is guided along the threaded ends.

A clamping force can easily be provided between the two clamping surfaces by the threaded ends and the nut parts, which are preferably provided with a lever. Using the optional lever it is even possible to tighten the clamp manually.

In a highly preferred embodiment of the clamp according to the invention the second elongate clamping surface can be removed substantially transversely of the clamping direction from the frame. It hereby becomes possible to remove the second clamping surface as soon as the clamping force has been released, whereby the clamp can be removed from the hose. Because the second clamping surface is removable, the clamp can be placed directly at the desired position on the hose.

When the clamping force is generated by the threaded ends, it is not necessary when the second clamping surface is removed in transverse direction to completely unscrew the nut parts from the threaded ends. The clamp can hereby be arranged quickly at the desired location on the hose.

In yet another preferred embodiment of the clamp according to the invention the second clamping surface is arranged on an elongate frame part which extends between the two threaded ends, and the frame part is provided on at least one end with a slotted hole extending transversely of the longitudinal direction of the frame part. The other end of the elongate frame part can optionally also be provided with a slotted hole.

Where reference is made above to a hose, this can also be a branched hose, which provides for additional ballast on the silo. The clamp according to the invention can be used here for instance to close off a branch from the other parts of the branched hose.

Owing to the slotted hole the frame part can be rotated away around a threaded end and the second clamping surface can thereby be removed.

These and other features of the invention will be further elucidated with reference to the accompanying drawings.

Figure 1 is a perspective view of a silo with partially removed parts .

Figure 2 shows a second situation of the silo according to figure 1.

Figure 3 shows an embodiment of the clamp according to the invention .

Figure 4 is a cross-sectional view of the clamp according to figure 3 in clamping position.

Figure 1 is a perspective view of a silo 1. This silo has a floor 2, with upright walls 3 along two or three sides of floor

2. Stored between walls 3 is animal feed or another type of product

4 which is covered with a layer of plastic 5.

Lying along the periphery of the layer of plastic 5 is a flat ballast hose 6, which is filled with a liquid such as water for the purpose of holding the layer of plastic 5 on animal feed .

The two ends 7,8 of hose 6 are sealed and provided with valves 9,

10. Liquid can flow out of hose 6 or be introduced therein via these valves .

When animal feed 4 now has to be removed from silo 1, clamps

11 can be arranged on hose 6 (see figure 2) . Valves 9, 10 are then opened to allow liquid to drain from the part of hose 6 between clamps 11 and the valves 9, 10. The layer of plastic 5 can subsequently be taken off animal feed 4. The excess part of the layer of plastic 5 can then be rolled up to form a roll 12.

Clamp 11 is shown in further detail in figure 3. Clamp 11 has a frame 13 between which two rollers 14, 15 are arranged parallel to each other.

Two threaded ends 16, 17 are arranged between the two rollers 14, 15 and at right angles thereto. A third roller 18 is guided between these two threaded ends 16, 17. Roller 18 is arranged around a strip 19 which is provided on the one side with a slotted hole 20 perpendicularly of the longitudinal direction, while the other side has a slotted hole 21 which lies in longitudinal direction. Owing to these slotted holes 20, 21 the third roller 18 can easily be removed transversely of the clamping direction.

Clamping of third roller 18 on the two rollers 14, 15 takes place by tightening nut parts 22, 23. Nut parts 22, 23 are provided with a lever 24, 25 in order to tighten the nut parts by hand. A hexagon 26, 27 is further provided on nut parts 22, 23 so that nut parts 22, 23 can also be tightened with tools.

During clamping of the filled hose 6 the hose is placed between third roller 18 and rollers 14, 15. Nut parts 22, 23 are then tightened so that third roller 18 is pressed against rollers 14, 15 and hose 6 is thereby clamped shut.

Figure 4 shows a cross-section wherein hose 6 is being clamped shut by roller 18 and rollers 14, 15. Also clearly shown is that rollers 14, 15 are provided with a resilient layer 28, 29 so as to compensate for possible unevenness or irregularities.

It will be further apparent that the wall parts of hose 6 are pressed against each other and hose 6 is thereby closed.