DE1066002B - - Google Patents

Description

In floating cranes it is known to separate the rear part of the pontoon via a bulkhead and with it to provide a pump device so that this part can be filled with water as required and so is effective as a counterweight. Here you have to take into account that without load and with the largest possible The load moment at the point of the pontoon that is deepest into the water is still sufficient large freeboard is available. Since only one side is immersed in these two extreme positions, but the other one rises out of the water, can only be less than half the volume of the pontoon for the Buoyancy can be exploited. The permissible load moment is therefore still - based on the pontoon volume - relatively small.

A floating crane with two separate floating bodies has also been proposed which both floats are connected to one another by a carrier. Here is on the carrier a cantilever. The connection between the carrier and the floating bodies takes place through Joints which allow the floats to be rotated against each other and which have the purpose of that a misalignment or a vertical movement of a floating body without influence on the other's position. The turning of the floats in the water, which in this case also serves to enable pivoting movements of the boom, but not only requires a relative one high expenditure of energy, but is also very slow, so that the Work performance of the floating crane is a relatively low. Furthermore, it is already known to provide two floating bodies for a floating slewing crane, one of which carries a support column, on which a boom is rotatably mounted by means of a bell. The second float is over Another boom is firmly connected to the bell and serves as a counterweight for the first boom and can be filled with water for this purpose, depending on the respective load torque. In this case, too, the load boom is pivoted in that the second floating body, which serves as a counterweight to the main float can be rotated. Also at This crane is therefore associated with a swiveling of the boom with a high expenditure of time and energy. In addition, however, the one connecting the second float to the bell of the load boom has Cantilever to absorb high bending loads. It has also already been suggested that one Manufacture floating crane from two separate floating bodies that can be rotated against each other, each of which floats with a support column

Floating crane

Applicant:

Krupp-Ardelt G.m.b.H., Wilhelmshaven

Karl Macrander ₁ Wilhelmshaven, has been named as the inventor

is provided. Both support columns are connected by means of joints through a horizontal beam, on which a movable slewing crane is arranged

so is. In this case, depending on the position of the slewing crane, the two floating bodies must be against each other be rotated to achieve appropriate lateral stability. The one from the respective boom rotation dependent rotational movement of one or both floats also requires large Energy and time expenditure.

The invention is based on the problem of the disadvantages of the known floating cranes with simple Means to avoid. According to the invention, it is primarily proposed that at least three, preferably four pontoons, each receiving a single support, are arranged around a common center point are. This can be achieved in a simple manner that when rotating the boom system the pontoons can remain at rest and therefore the rotary movements of the boom system with accordingly higher speeds are to be carried out. They each serve on the opposite side Side of the boom system as a counterweight.

Around the individual supports with which the bridge girder is supported on the individual pontoons, to keep as free as possible from bending stresses and to ensure that the individual pontoons always lie as horizontally as possible in the water, regardless of whether they are subjected to pressure forces and are accordingly pressed into the water or whether they are subjected to tensile forces and accordingly are pulled out of the water, it is proposed according to a further step of the invention, that each individual support with the associated pontoon through a two support points Connection point is connected, of which the support point for the transmission of perpendicular compressive forces

909 629/71

Claims (5)

the individual support is arranged below the center of lift of the pontoon and the support point for the transmission of tensile forces is arranged above the center of gravity of the pontoon. In order to make the pontoons in the opposite direction to the boom suitable as counterweights, they can be filled with water in a known manner as required. In a further embodiment of the invention it is proposed for this purpose that each pontoon can be filled with water via its own or a central pump device as required. In particular, it is advantageous if an automatic control of the pump device is provided, which actuates the pump device as a function of the respective rotational position of the boom and the water level in the pontoons. Preferably, an upper bearing control can be provided, which actuates the pump device depending on the crane outreach or the submerged rivet of the jib-side pontoon. In the drawing, an embodiment of the invention is shown schematically, namely FIG. 1 shows the top view of a floating crane designed according to the invention and FIG. 2 shows the connection of a support to the associated pontoon. A crane superstructure 2 is connected to a bridge girder 4 on four pontoons 1 via a bearing 3 which transmits tilting moments. The bridge girder 4 is supported by individual supports 5 on one pontoon 1 each. Each pontoon either has its own pump device, not shown in the drawing, or can be filled or emptied with water as required via a central pump device attached to the bridge girder. The pontoons standing in the boom direction are emptied during operation, while the pontoons arranged on the side facing away from the boom are more or less filled with water. Each filling of a pontoon with water applies to a pivoting range of the boom 6 of 90 °. At points 7, the pump device is switched over for one pontoon, i. That is, a pontoon filled with water is emptied, while the pontoon following in the direction of rotation of the boom is filled with water. However, an interpolating control can also be used for the pump device, i. That is, the water of a pontoon is pumped around within a transition zone, a certain amount of water being assigned to each pontoon for each rotational position of the crane within this zone. The corresponding water level can be scanned * s in every pontoon. In Fig. 2, the connection point of a single support 5 with a pontoon 1 is shown on an enlarged scale. A yoke 8 is attached to the individual support 5, the crosshead 9 of which has a respective downwardly projecting nose 10 and an upwardly extending nose 11. Of these, the nose 10 interacts with a bearing piece 12 arranged below the center of lift of the pontoon 1, and the nose 11 cooperates with a bearing piece 13 arranged above the center of gravity of the pontoon 1. In the vertical direction there is a slight bearing play of the support points between the nose 10 and the bearing piece 12 or between the nose 11 and the bearing piece 13, so that the transition from one type of bearing to the other cannot be impaired by any inclined position of the bridge girder 4. Patent claims: 1. Floating crane with a rotatable boom system on a bridge girder which is supported by individual supports on independent pontoons, characterized in that at least three, preferably four, pontoons (1) each accommodating a single support (5) are arranged around a common center point. 2. Floating crane according to claim 1, characterized in that each individual support (5) is connected to the associated pontoon (1) by a connection point having two support points (10, 12 or 11, 13) , of which one support point (10, 12) for the transmission of vertical compressive forces of the individual support is arranged below the center of lift of the pontoon and the other support point (11, 13) for the transmission of tensile forces is arranged above the center of gravity of the pontoon. 3. floating crane according to claim 1 or 2, characterized in that each pontoon by a your own or a shared pump system is to be filled with water. 4. Floating crane according to claim 3, characterized by an automatic control of the pump device as a function of the rotational position of the boom (6) and the water level in the pontoons. 5. floating crane according to claim 4, characterized by an overlay control for the pump device for additional consideration of the crane radius or immersion depth of the boom-side pontoon dependent command values. Considered publications:
German patents No. 341 044, 336 224,
836 1 sheet of drawings ® 909 629/71 9.59