Patent Publication Number: US-4646449-A

Title: Bucket wheel dredging device

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to a bucket wheel cutting device with two cutting wheels for a floating dredge with suction tube conveyance. 
     A conveying device for a floating suction dredge, to whose suction tube two bucket wheels are attached, is already known from German OS No. 1,484,781. 
     In one such conveying device, however, the bottom being cut (dredged) by the cutting wheels is only partially captured and carried away by the suction stream of the dredging pump. 
     SUMMARY OF THE INVENTION 
     An object of the present invention resides in providing a bucket wheel cutting device in which it is assured that the excavated material being cut is carried away at a high volume efficiency. 
     Toward this end the invention provides a device as set forth above wherein the suction tube has an end with two suction chambers separated by a central partition, one of the cutting wheels being provided at each of the two sides thereof, and which suction chambers can be closed alternately, relative to the suction tube, by means of an adjustable flap. Here the suction chambers are provided predominantly in the lower region of the cutting wheels, and these have cutting openings at their sides. 
     Characteristic advantages are achieved by the solution of the problem in accordance with the invention, in the operation of the bucket wheel dredge, in terms of constant and unequivocal cutting conditions, and a constant, highly efficient removal of the excavated material can be assured. The material loosened by the cutting is sucked away directly through the cutting openings. Because of the ability to block off the other suction chamber associated with the cutting wheel that is not removing material, the suction and transporting of additional water is prevented. 
     Accordingly a further object of the invention is to provide a bucket wheel cutting device for a floating dredge which comprises support structure that carries a suction tube having an end portion, a pair of cutting wheels which are mounted for common rotation on opposite sides of the end portion of the tube, a tube containing a partition for dividing the end portion into two opposite chambers each associated with one of the cutting wheels, and a flap movable in the suction tube for alternately establishing communication between one of the chambers and a remainder of suction tube. 
     A further object of the invention is to provide a bucket wheel cutting device which is simple in design, rugged in construction and economical to manufacture. 
    
    
     The various features of novetly which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
     FIG. 1 is a side elevational view of the bucket wheel cutting device; and 
     FIG. 2 is a bottom plan view of the device of FIG. 1. 
    
    
     BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT 
     According to FIG. 1, the inventive bucket wheel device has two cutting wheels 1a and 1b, which are commonly driven hydraulically by a hydrometer 2, incorporated into the support structure of a suction tube boom, together with a transmission 3. A suction tube 4 ends in two suction chambers 5a and 5b, provided within the centrally arranged wheel support. These chambers are separated by a central partition 6 (also see FIG. 2). An adjustable flap 7 is provided, which connects only one of the suction chambers 5a or 5b with the suction tube 4, this chamber being associated with the conveying cutting wheel 1a or 1b, depending on the direction of pivoting of the suction tube boom during the dredging operations. Each of the suction chambers is bounded not only by the central partition 6, but also by the mechanical support structure and a skimmer (not shown). 
     Cutting brackets 8a and 8b, fitted respectively with cutting knives 9a and 9b, expose cutting openings at the sides which provide for intake of the excavated material into the suction chambers. It can also be seen from the figures that suction chambers 5a and 5b are provided predominantly in the lower region of cutting wheels 1a and 1b, i.e. directly behind the bottom bed of the waterway which is to be cut away. 
     The chambers 5a, 5b wheel support as shown in FIG. 1, and are elongated in the axial direction of the tube 4 and its boom, as is the partition 6. As also shown in FIG. 2, each chamber 5a,5b is open to the side and thus to its cutting wheel, at a location spaced from flap 7. The chambers are closed to the side near the flap. 
     FIG. 2 indicates the reference numbers given for the corresponding mechanical components. 
     By means of the bucket wheel cutting device elucidated above, it is possible to carry out extensive dredging operations which serve for maintaining and enlarging underwater structures. Because it is easily possible to pivot the suction tube boom laterally, thus sweeping out a working area to one side and the other, with excavation of large quantities of material, it becomes easy to steer the accompanying floating dredge, and in particular to achieve unequivocal positioning. In addition, it is possible with such a device to collect raw materials under water. This is true even in those cases where the excavated material must be loosened mechanically with a considerable consumption of energy. 
     The invention is a bucket wheel cutting device for a floating dredge comprising a suction tube 4 having an end with two suction chambers 5a, 5b, for material to be dredged and a partition 6 for separating the chambers, a cutting wheel 1a, 1b provided at each of two sides of the suction tube end, each cooperating with one of said suction chambers and a flap 7 movable in said tube end for alternately closing communication between said two chambers and a remainder of said suction tube 4. 
     While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.