BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to a cleaning device. More particularly, this invention relates to a device for use in cleaning of tanks and other storage containers.  
         [0003]     2. Description of the Prior Art  
         [0004]     Tank and other storage containers used for storing and transporting liquids usually can only be cleaned with extreme difficulty. As used herein, the term tanks shall include other storage containers. All the residue and sediment must be removed before the tank can be placed back into service. It has been customary to clean the interior of such tanks by alternately steaming and/or washing down the interior. In some cleaning operations, workmen must enter the tank to operate high pressure cleaning hoses. This type of cleaning operation is extremely hazardous to the workmen. It presents the possibly that workmen might be exposed to noxious, explosive or otherwise hazardous fumes generated by the residue and sediment in a tank to be cleaned.  
         [0005]     Prior art devices designed to clean the interior of tanks without necessitating the entrance of workmen into the tank tend  
       BACKGROUND OF THE INVENTION  
       [0006]     1. Field of the Invention  
         [0007]     This invention relates to a cleaning device. More particularly, this invention relates to a device for use in cleaning of tanks and other storage containers.  
         [0008]     2. Description of the Prior Art  
         [0009]     Tank and other storage containers used for storing and transporting liquids usually can only be cleaned with extreme difficulty. As used herein, the term tanks shall include other storage containers. All the residue and sediment must be removed before the tank can be placed back into service. It has been customary to clean the interior of such tanks by alternately steaming and/or washing down the interior. In some cleaning operations, workmen must enter the tank to operate high pressure cleaning hoses. This type of cleaning operation is extremely hazardous to the workmen. It presents the possibly that workmen might be exposed to noxious, explosive or otherwise hazardous fumes generated by the residue and sediment in a tank to be cleaned.  
         [0010]     Prior art devices designed to clean the interior of tanks without necessitating the entrance of workmen into the tank tend to be complex devices utlizing several nozzles or orifices for cleaning. This makes them costly to manufacture and difficult to manipulate. For example, U.S. Pat. No. 1,838,643 to Peterson et al, describes a complex tank cleaning device which utilizes a hose connected to a rigid vertical pipe for the distribution of the cleaning fluid. The nozzle of the hose is fixed to a gear box at the end of the vertical pipe. The inclination of the nozzle may be changed by rotating a set of beveled gears. The entire apparatus must be rotated in discrete steps and supported by a framework which rests on the tank.  
         [0011]     It would be an advantage to provide a device which does not require a supporting frame or complex construction and can be used effectively to clean all the interior surfaces of the tank without necessitating workmaen breaking the plane of entry into the tank.  
       SUMMARY OF THE INVENTION  
       [0012]     It is an object of the invention to obviate the disadvantages of the prior art.  
         [0013]     It is another object of the invention to provide a more mobile tank-cleaning device which does not require a support frame or complex construction.  
         [0014]     It is a further object of the invention to provide a tank cleaning device which can direct a jet of cleaning fluid at all the interior surfaces of a tank to provide complete cleaning.  
         [0015]     In accordance with one aspect of the invention, there is provided a device for cleaning tanks comprising a hollow, continuous, rigid pipe having a straight portion and a curved portion, the straight portion having a connecting end for connecting to a source of cleaning fluid, the curved portion being substantially semicircular and having a nozzle end for emitting a stream of cleaning fluid.  
         [0016]     In accordance with another aspect of the invention, there is provided a method for cleaning tanks wherein the method involves inserting a tank cleaning device into a tank, the tank cleaning device comprising a hollow, continuous, rigid pipe having a center axis, straight portion and a curved portion, the straight portion having a connecting end for connecting to a source of cleaning fluid, the curved portion being substantially semicircular and having a center point and a nozzle end; supplying a source of pressurized cleaning fluid to the tank cleaning device to cause a jet of cleaning fluid to be emitted from the nozzle end; and rotating the tank cleaning device about the center axis and the center point to cause the jet of cleaning fluid to impinge on an interior wall of the tank.  
         [0017]     In accordance with still another aspect of the invention, there is provided a device for cleaning tanks comprising a flexable hose having a nozle and connectable to a source of cleaning fluid, the flexible hose being disposed within a hollow, continuous, rigid pipe having a center axis, straight portion and a curved portion, the curved portion being substantially semicurcular and having a center point, and an open end, the nozzle being disposed in the open end of the curved portion.  
         [0018]     In accordance with a further aspect of the invention, there is provided a method for cleaning tanks wherein the method involves inserting a tank cleaning device into a tank, the tank cleaning device comprising a flexible hose having a nozzle and connectable to a source of cleaning fluid, the flexible hose being disposed in a hollow, continous, rigid pipe having a center axis, straight portion and a curved portion, the curved potion being substantially semicurcular and having a center point, and an open end, the nozzle being disposed in the open end of the curved portion; suppling a source of cleaning fluid to the hose to cause a jet of cleaning fluid to be emitted from the nozzle; and rotating the tank cleaning device about the center axis and the center point to cause the jet of cleaning fluid to impinge on an interior wall of the tank.  
         [0019]     Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  is a view of the tank cleaning device of the present invention.  
         [0021]      FIGS. 2-6  are vertical cutaway views of a tank illustrating the use of the tank-cleaning device therein.  
         [0022]      FIGS. 7 &amp; 8  are views of alternate nozzle end designs of the tank-cleaning device.  
         [0023]      FIG. 9  is a view of another embodiment of the tank-cleaning device wherein a flexible hose is inserted in a preformed distributor. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]     The present invention is a tank cleaning device which uses a continuous, curved, rigid distributor to emit a jet of cleaning fluid (i.e. water) from a nozzle connected to the end of the distributor. In another embodiment, a double braided hydraulic hose having a nozzle connected to its end is inserted into a preformed continuous, curved, rigid distributor to emit a cleaning fluid. The cleaning fluid may be steam or other suitable chemical cleaning fluid which is supplied to the distributor under pressure. The device has the ability to rotate freely around a center axis while permitting rapid and continuous adjustment of the inclination of the nozzle end with respect to the horizontal plane of the tank. This allows a jet of cleaning fluid to be rapidly directed to reach all the inside walls of a tank for complete cleaning. The cleaning fluid containing the residual product and sediment is washed down to the bottom of the tank where it is drawn off. The use of the present invention yields a complete cleaning sufficient to permit the tank to be placed back into service. Tanks amy be cleaned without necessitating the entrance of workmen into the tank or if desired the tank cleaning device permits a safer tank atmosphere to be obtained prior to workmen entering. Unlike other prior art devices, no supporting frame or complex mechanical devices are required to manipulate the nozzle.  
         [0025]     Referring to  FIG. 1 , one embodiment of a tank cleaning device  10  is formed of a hollow, continuous, pipe  12  capable of containing a pressurized fluid. The pipe  12  is made of a rigid material such as a plastic, metal or fiberglass although other suitable materials that are presently used in the manufacture of pipes and which are sufficiently rigid may also be used. Pipe  12  has a straight portion  34  and a curved portion  16 . Straight portion  34  has a connecting end  14  for connecting to fluid supply coupling  20  which in turn is connected to a source or multiple sources of a pressurized cleaning fluid (not shown). Nozzle end  18  is attached to the curved portion  16  and opposite connecting end  14  for delivering a stream of fluid cleaning fluid to the tank walls. Nozzle end  18  may consist of a connector and a detachable nozzle. Curved portion  16  is substantially semicircular to allow the tank cleaning device  10  to be at least partially inserted into the tank through the manhole opening and to permit rapid and continuous adjustment of the inclination of nozzle  18  by rotating curved portion  16  about center point  32 . Tank cleaning is effectuated by rotating the device  10  about center axis  2  while changing the inclination of nozzle  18 . In this manner, a forceful stream of cleaning fluid capable of reaching the upper and lower interior surfaces of the tank is delivered in a revolving fashion. A few of different cleaning movements that may be made by tank cleaning device  10  are illustrated in  FIGS. 2-6 .  
         [0026]     In a preferred embodiment, the continuous hollow pipe  12  is made of a plastic material. Plastic is preferred because of its ability to be readily shaped into a sufficiently rigid form while still light and strong. Curved portion  16  has a radius  4  of about 15 inches. The radius  4  may vary depending on the size of the tank to be cleaned or the tank opening. For example, a greater radius may be needed for the cleaning of a larger tank and conversely a smaller radius for a smaller vessel. The pipe  12  has an inside diameter of about 2 inches but may, depending on the size of the tank to be cleaned, be greater or lesser in diameter as necessary to facilitate the cleaning of different size tanks. The straight portion  34  of the pipe  12  has a connecting end  14  constructed so as to be connectable to a standard hose or pressure hose coupling. The pressure from the presurized source may vary from 20 psi to a high pressure of 4000 psi. For example, 20 psi normally is used to clean smaller tanks or drums. Variances may be made in the pressure depending on the container to be cleaned and the type of device needed for the pressure required. The straight portion  34  is normally about 6 inches in length, but may vary in length depending on the size of the tank and the depth that the device has to be inserted therein. The nozzle end  18  is tapered to a diameter narrower than pipe  12  so as to produce a high velocity jet of fluid exiting therefrom. Nozzle end  18  may also be constructed to accept a detachable nozzle to vary the force pattern and quantity of the fluid exiting therefrom. Fluid supply coupling  20  and connecting end  14  may be constructed to permit 360° rotation about center axis  2  without entangling the attached hose.  
         [0027]     Another embodiment of the present invention, is shown in  FIG. 9 . A flexible hose  42  inserted within a preformed distributor  44  having the same shape as the hollow continuous pipe shown in  FIG. 1 .  
         [0028]     Preferably, the flexible hose  42  is a double braided hydraulic hose. Preformed distributor  44 , has a straight portion  34  and a curved portion  16 . Straight portion  34  is used for directing the device when it has been placed within a tank. The hose  42  has a connecting end  48  for connecting to a fluid supply or to a source or multiple sources of a pressurized cleaning fluid (not shown). Nozzle  46  is attached to the end of the hose  42  and opposite the connecting end  48  for delivering a stram of fluid cleaning fluid to the tank walls. Nozzle  46  is disposed in the open end  50  of the curved portion  16 . Curved portion  16  is substantially semicurcular to allow the tank cleaning device  10  to be at least partially inserted into the tank through the manhole opening clean out or clean out pipe.  
         [0029]     Preferably distributor  44  is made of an aluminum material.  
         [0030]     Although a pressure of 3000 psi is the pressure most commonly used with the device for the cleaning of tanks, for more problematic cleaning the invention could receive and deliver cleaning fluid at 4000 psi or higher psi at varied quantiaites in various patterns by utilizing matereials of different rigidity capable of withstanding higger pressure and heat requirements.  
         [0031]     Alternative nozzle designs are shown in  FIGS. 7 &amp; 8 . In these embodiments, the nozzle end  18  is slightly curved in the direction opposite the curvature of the curved portion  16 . A detachable nozzle  40  is attached to the nozzle end  18 .  
         [0032]     Referring to  FIGS. 2-6 , tank cleaning device  10  is shown inserted through the opening, or manhole,  36  in the top of tank  22  to permit access to the interior of the tank. Near the bottom of interior wall  24  is an opening  30  for receiving a valve (not shown) whereby the contents of the tank  22  maybe emptied. Device  10  delivers the pressurized cleaning fluid outwardly in a jet stream  7  to impinge against the inner wall surfaces  24  of the tank  22  in a pattern defined by the rotating of the curved portion  16  about its center point  32  and about its center axis  2 . Because the device has the ability to move simultaneously in two different directions, it is possible to generate a sweeping action, e.g. moving the jet stream  7  from side to side or from top to bottom, to more quickly clean the interior surface of the tank thereby making the cleaning process more efficient and thorough. The force of the jet stream and action of the cleaning fluid dislodge the residual product and sediment from the wall  24 . The contaminated cleaning fluid is discharged through opening  30  and collected for proper disposal.  
         [0033]     While the invention has been described with regard to a specific embodiment thereof, it will be understood by those skilled in the art to which the invention pertains that numerous changes may be made in the invention without departing from the spirit or scope thereof.
A device for cleaning the inside of tanks or other storage containers used in the transporting or storage of liquids comprises a hollow, continuous, rigid pipe having a straight portion and a curved portion, the straight portion having a connecting end for connecting to a source of cleaning fluid, the curved portion being substantially semicircular and having a nozzle end for emitting a stream of cleaning fluid. The jet of cleaning fluid is directed against the inside walls and bottom of the tank facilitating removal of residual product and sediment.