Water Craft and Method for Removing Weeds and Pollutants From Navigable Waters

In order to protect the environment of sea ports, harbors and waterways, navigable water craft have now been developed and placed into use for removing debris such as flotsam and jetsam which are removed by a basket or scoop mounted at the bow of the vessel to be movable under control of an operator into and out of the water to pick up the debris and dump it onto nearby barges or collection containers. Such craft are disclosed in U.S. Pat. Nos. 3,326,379 and 3,434,444 assigned to the same assignee as the subject application. Although such craft have been found to be quite effective in removing and handling floating debris, they still leave unattended the problem of removing weeds and other marine vegetation from the beds of waterways, canals, channels, etc. Such vegetation have been known to render waterways unnavigable and in other situations, it has caused serious blockage of the water flow.

Another deficiency of conventional pollutant control water craft is that their cooling systems for the engines which propel the craft are susceptible to blockage by debris and marine vegetation due to the fact that the craft operates in polluted or debris-ridden areas.

An object of the present invention is to provide a navigable water craft capable of ripping out weeds or other marine vegetation from the beds of navigable waters. Additionally, it is an object to provide such water craft that is also capable of removing flotsam, jetsam and other floating debris from navigable waters.

Another object of the present invention is to provide a novel method of removing weeds and other marine vegetation from the beds of navigable waters. Included herein is such a method which utilizes a navigable water craft.

A further object of the present invention is to provide a novel weed removal tool and system that may be used on navigable water craft for removing weeds and marine vegetation from the beds of navigable waters.

A still further object is to provide a navigable water craft that has a novel arrangement of tools and accessories for removing floating debris and rooted weeds from navigable waters. Included herein is such a water craft that may be easily operated by but a single person.

Another object of the present invention is to provide such a navigable water craft that is steered through a rudder that is protected from debris in the water as well as the weed removal operations conducted through the use of the water craft.

A still further object of the present invention is to provide such a water craft that incorporates a novel cooling system for the engine which propels the water craft and which cooling system is not susceptible to blockage by debris or other foreign matter existing in the water.

Another object of the present invention is to provide a navigable water craft having a tool that may be raised and lowered relative to the water and rotated about a vertical axis for the purpose of removing flotsam, jetsam and other debris or pollutants from navigable waters.

In one aspect, the present invention provides a method and apparatus for ripping out weeds and other vegetation from the beds of waterways by utilizing a weed removal tool that is lowered from a navigable craft into the water and dragged along the bed as the craft is propelled forwardly. The tool is attached to a line wound about a motorized winch mounted on the craft. In the preferred embodiment, the tool is lowered and raised from the stern of the craft, and a barrier is mounted at the stern to protect the rudder from the tool as the latter is raised and lowered.

The craft of the present invention also contains a tool in the form of a scoop or basket mounted on the bow to be raised and lowered into the water for removing flotsam, jetsam and other debris and pollutants from the water. The basket is also mounted to be rotated about a vertical axis to position the basket to either side of the craft or any points therebetween. A control station is located intermediate the bow and the stern from which a single operator may control the various operations of the craft including navigation of the craft.

In addition, the craft includes a closed circuit cooling system for cooling the engine. The cooling system includes a coolant tank located at the bottom of the hull and forming a part thereof so as to be submerged into the water in heat exchange contact with the water. Other features of the invention will be described below.

Other objects and advantages of the present invention will be apparent from the following more detailed description taken in conjunction with the attached drawings in which:

FIG. 1 is a side elevational view of a water craft embodying the present invention shown in the water and with its front end scoop raised;

FIG. 2 is a top plan view of the craft;

FIG. 3 is a bottom plan view of the craft;

FIG. 4 is a fragmental cross-sectional view taken generally along lines 4--4 of FIG. 3;

FIG. 5 is a rear end view of the craft shown with its weed removal tool lowered;

FIG. 6 is an enlarged fragmental bottom plan view of the craft and with parts broken away to show the inside of a cooling tank included in the engine cooling system;

FIG. 7 is a fragmental cross-sectional view taken generally along lines 7--7 of FIG. 6;

FIG. 8 is a fragmental side elevational view at the bow of a craft showing a modification utilized to revolve the scoop about a vertical axis; and

FIG. 9 is a top plan view of the craft shown in FIG. 8 with its scoop removed to show its turntable.

Referring now to the drawings in detail, there is shown for illustrative purposes only a water craft embodying the present invention. Referring to FIG. 1, the craft includes a hull generally designated 10 formed from steel plate or other suitable sturdy material, a bow area 12 and a stern area 14. The hull bottom 10a is generally flat and terminates short of the stern to provide a recessed understern where a propeller 16 is mounted to be driven by a suitable engine not shown. Rearwardly of the propeller 16 is mounted a rudder 18 for steering the craft. The lower sides 10c of the hull slant downwardly and upwardly from vertical upper sides 10d and at their rear converge inwardly at 10b to the longitudinal centerline or beam of the craft.

Referring to FIG. 1, at the bow area 12 on the upper deck is mounted a tool in the form of a scoop or basket 20 for removing from the water flotsam and jetsam or other debris and pollutants. Scoop 20 is pivotally mounted to a pair of booms 22 whose bases are pivoted at 23 to the top deck. The booms 22 are raised or lowered by hydraulic rams 24 anchored at 26 to the deck and connected to the midsections of the booms at 28. Scoop 20 is pivotable relative to the booms 22 by means of hydraulic rams 30 and a linkage 32 connecting the rams 30 to the scoop 20. The scoop 20 and its mounting booms 22 and hydraulic rams 24 and 30 are well-known as indicated in the aforementioned U.S. Pat. Nos. 3,326,379 and 3,434,444 and therefore need no further description.

Navigation of the craft including control of the engine and rudder 18 as well as the scoop 20 is achieved by an operator at a central station located behind the scoop where an operator's seat 34 and controls 36 are located. Behind the control station the craft has a raised deck 13 extending to the stern along the longitudinal central section of the craft leaving walkways 15 on opposite sides thereof on the main deck. A pair of hatches 7 are provided on the raised deck to provide access to the engine forwardly of a recessed winch compartment to be described below.

In accordance with the present invention, there is mounted on the raised deck 13 at the stern area, a weed removal tool generally designated 40. In the preferred embodiment, tool 40 includes three heavy rigid members 42 formed, for example, from steel I beams welded or bolted together to form a triangular structure whose opposite sides are equal in length. In its idle position shown in FIGS. 1 and 2, tool 42 lies in a generally horizontal plane on the raised deck 13 at the stern area with its forward apex generally aligned above the longitudinal centerline of the craft and with its rearmost side 42a projected beyond the stern and extending at right angles to the longitudinal centerline of the craft as best shown in FIG. 2. Projecting from the forward apex of the tool 40 is a tie plate 44 to which is tied a line or cable 46 whose opposite end is wound about a rotatable winch 48 mounted to extend transversely across the centerline of the craft preferably in a recess 52 located in the upper deck 13. The upper end of the recess 52 is open but its opposite sides are closed. Winch 48 is driven by a motor 50 through controls at the control station. Rotation of the winch 48 in one direction will pay out the line 46 to lower the tool 40 from the stern into the water as illustrated in FIG. 5 to engage along the bed to rip out weeds and other vegetation as the craft is propelled forwardly. Rotation of the winch 48 in the opposite direction will, of course, raise the tool 40 onto the raised deck 13 into the idle position shown in FIGS. 1 and 2. To facilitate movement of the tool as well as to guide the tool in movement to and from its idle position, a roller 60 is mounted for rotation across the stern on the raised deck 13. Roller 60 engages the undersurface of the sides 42 of the tool and is provided with an outer layer of rubber or other flexible and resilient material.

In order to protect the rudder 18 from the tool 40 during raising, lowering or operation of the tool 40, a barrier generally designated 70 is provided at the lower stern behind the rudder 18. In the preferred embodiment, the barrier 70 includes steel bars 74 fixed to and diverging downwardly away from a steel cross bar 72 fixed across the stern as shown in FIG. 5. A plurality of cross struts 76 also formed from steel bars are fixed such as by welding to and between bars 74 at vertically spaced locations as shown in FIG. 5. The bottom of the barrier 70 is anchored to the bottom of the hull by means of a rigid steel bar 78 extending along the longitudinal centerline of the craft as best shown in FIGS. 1 and 3. As shown in FIG. 1, the rudder 18 is mounted for pivotal movement in bearings 19 fixed to a post 21 whose upper end is fixed to the hull and whose lower end is secured to bar 78. As shown in FIG. 5, the barrier provides a cage over the rudder 18 preventing the weed removal tool 40 or the tow line 46 from engaging the rudder during use of the weed removal tool. Since the weight of the barrier 70 may be on the order of 500 pounds buoyancy, tanks may be provided in the hull at the stern at 14a shown in FIG. 5.

The engine which drives the propeller 16 is conventional, however, a closed circuit coolant system is utilized to cool the engine. In accordance with another feature of the invention, a coolant tank generally designated 80 is provided at the bottom of the hull as shown in FIGS. 3, 6 and 7 to lie in heat exchange relationship with the water 11. In the preferred embodiment, coolant tank 70 has a generally rectangular cross section including a flat bottom wall 82 spaced from the bottom wall 10a of the hull and side walls 84 extending between walls 10a and 82 to enclose a space for receiving coolant which is admitted into the tank and discharged therefrom through ports 86 and 88 formed in the hull wall 10a. The coolant which may be fresh water or other coolant liquid is circulated throughout the coolant tank from the inlet port 86 to the outlet port 88 by means of longitudinal channels formed in the tank by flat partition walls 90 fixed to and between walls 10a and 82. Partition walls 90 provides a continuous serpentine path for the coolant to enhance heat exchange with the external sea water through the coolant tank walls and partitions. It will be seen that the use of a closed circuit coolant system and the placement of the coolant tank 70 avoids the problem attending conventional cooling systems that utilize sea water as the coolant and which are susceptible to clogging by debris, weeds and other foreign matter existing in the sea or body of water in which the craft is operating.

In the preferred embodiment, the coolant tank is made of steel plate or other material of similar strength and is placed to extend longitudinally on the bottom of the hull so as to be centered and symmetrical with respect to the longitudinal centerline of the craft as shown in FIG. 6. In order to provide a degree of protection to the coolant tank 70 as well as to reinforce the bottom of the hull, a pair of stiffening ribs 92 are fixed to the bottom wall 10a of the hull to extend longitudinally thereof on opposite sides of the coolant tank 60. Reinforcing ribs 92 may take the form of structural steel members such as angle irons, and they are dimensioned to extend downwardly beyond the plane of the bottom wall 82 of the coolant tank as shown in FIGS. 3 and 7. The bottom wall of the hull at the bow area is also reinforced with ribs 94 as shown in FIGS. 3 and 4.

Referring now to FIGS. 8 and 9, the bow portion of a modified craft is shown on which the scoop 20 is mounted to also be movable about a vertical axis 102 located on the longitudinal centerline of the craft to enable the scoop to be moved to either side of the craft or any points therebetween. In the specific embodiment shown, this is accomplished through a turntable 100 mounted for rotation about its center on a shaft 102. The boom 30 and its associated hydraulic rams 24 and 30 are mounted in apertures 104 in the turntable 100 through ears 106 fixed within apertures 104. Turntable 100 is provided with gear teeth on its periphery in mesh with a drive pinion 110 driven by a hydraulic motor 112 or any other suitable means under the control of the operator at the control station. Rotation of pinion 110 will, of course, rotate turntable 100 in either of two directions at the selection of the operator. In addition and as described above, the scoop may be raised or lowered through the boom 22 and its ram 24 and may be pivoted relative to the boom 22 through ram 30. Other than the turntable 100 and its associated gearing and pinion 110, the craft of FIGS. 8 and 9 is the same as the craft disclosed in FIGS. 1 to 7 and described above.