Abstract:
A pressurized liquid dispensing mobile unit used to treat metallic surfaces by applying liquid under pressure to such surfaces. The pressurized liquid dispensing mobile unit has two endless tracks that move the unit over the surface being treated. Each track has magnetic sections that hold the unit to the surface being treated. Liquid under pressure is supplied to liquid dispensing means that are mounted for movement between a first position at which liquid is dispensed under pressure and a second position at which liquid is not dispensed and an observer has an unobstructed view of the liquid dispensing means. The movement of the pressurized liquid dispensing mobile unit along the surface being treated and the supply of liquid under pressure to the unit for treatment of the surface on which the pressurized liquid dispensing mobile unit is mounted are controlled from a remote location.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates, in general, to the treatment of structural surfaces and, in particular, to the cleaning of large structural surfaces by the application of water under very high pressure. 
       BACKGROUND 
       [0002]    There are many large structural metallic structures, such as the hulls of ships, oil storage tanks, gas holders, and buildings, that require maintenance. Such maintenance can include cleaning paint, rust, and debris from the surface of the structure. 
         [0003]    Among the ways these structures are cleaned is grit blasting. Grit blasting is expensive and exposes the operators of the equipment to health hazards. 
         [0004]    Another common practice for cleaning large metallic structures is to apply water under high pressure to the surface being cleaned. There are many remotely controlled pressurized water dispensing mobile units in use today for cleaning large metallic surfaces. Generally, these units suffer from one or more shortcomings. Some are very expensive. Others function at much too slow rates. Some are difficult or expensive to maintain. Others suffer from the shortcoming that the pressure of the water being dispensed is limited by the “holding” capability of the mobile unit to the surface of the metallic structure being cleaned. As the water pressure is increased, the back pressure tends to separate the mobile unit from the surface being cleaned. Higher pressures are desired because higher pressures increase the effectiveness of the mobile cleaning unit in greater efficiency and reduced costs. 
       SUMMARY 
       [0005]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, includes a frame having first and second parallel longitudinal sides, first and second gear wheels mounted to the frame at the first longitudinal side of the frame for rotary movement relative to the frame, and a first endless track having a plurality of magnetic sections extending between and around the first gear wheel and the second gear wheel for movement parallel to the first longitudinal side of the frame as the first gear wheel and the second gear wheel undergo rotary movement. A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes third and fourth gear wheels mounted to the frame at the second longitudinal side of the frame for rotary movement relative to the frame and a second endless track having a plurality of magnetic sections extending between and around the third gear wheel and the fourth gear wheel for movement parallel to the second longitudinal side of the frame as the third gear wheel and the fourth gear wheel undergo rotary movement. A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, further includes a first power source mounted to the frame and a second power source mounted to the frame. The first power source is coupled to the first endless track by first coupling means to impart movement to the first endless track and the second power source is coupled to the second endless track by second coupling means to impart movement to impart movement to the second endless track. A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, further includes liquid supply means for supplying liquid under pressure and liquid dispensing means mounted for movement between and a first closed position at which liquid is dispensed and a second open position at which liquid is not dispensed and an observer has an unobstructed view of the liquid dispensing means. A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes control means for selectively activating the first power source to impart movement to the first endless track, selectively activating the second power source to impart movement to the second endless track; and selectively supplying liquid under pressure from the liquid supply means to the liquid dispensing means. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a front view, partially in section, of a pressurized liquid dispensing mobile unit constructed in accordance with the present invention. 
           [0007]      FIG. 2  is a top view of the  FIG. 1  pressurized liquid dispensing mobile unit. 
           [0008]      FIG. 3  is a rear view of the  FIG. 1  pressurized liquid dispensing mobile unit. 
           [0009]      FIG. 4  is a bottom view of the  FIG. 1  pressurized liquid dispensing mobile unit. 
           [0010]      FIG. 5  is a side view of the  FIG. 1  pressurized liquid dispensing mobile unit, taken from the right side of  FIG. 1 , with the liquid dispensing means disposed in the closed position at which liquid is dispensed. 
           [0011]      FIG. 6  is a side view, similar to  FIG. 5 , of the  FIG. 1  pressurized liquid dispensing mobile unit with the liquid dispensing means disposed in the open position at which liquid is not dispensed. 
           [0012]      FIG. 7  is a bottom view, similar to  FIG. 4 , of the  FIG. 1  pressurized liquid dispensing mobile unit with different liquid dispensing means from the  FIG. 1  liquid dispensing means. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0013]    Referring to  FIGS. 1 through 6 , a pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, includes a frame  10  having first and second parallel longitudinal sides  10   a  and  10   b,  respectively. Frame  10  can be fabricated from a suitable metal and provides support for various components of the pressurized liquid dispensing mobile unit to be described. 
         [0014]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes first and second gear wheels  12  and  14 , respectively, mounted to frame  10  at first longitudinal side  10   a  of the frame for rotary movement relative to the frame. First gear wheel  12  is mounted for rotation to frame  10  by a first axle  16  and second gear wheel  14  is mounted for rotation to frame  10  by a second axle  18 . 
         [0015]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes a first endless track  20  having a plurality of magnetic sections  22  extending between and around first gear wheel  12  and second gear  16  wheel for movement parallel to first longitudinal side  10   a  of frame  10  as the first gear wheel and the second gear wheel undergo rotary movement. First endless track  20  includes a first endless sprocket chain  24 , shown most clearly in  FIGS. 5 and 6 , that engages first gear wheel  12  and second gear wheel  14  and extends between and around the first and second gear wheels. Magnetic sections  22  of first endless track  20  are treads extending transverse to the direction of movement of the first endless track and are secured by suitable means to move with first endless sprocket chain  24 . Magnetic sections  22  can be formed of a rare earth material such as the special neodymium magnetic assembly sold by Magnetic Hold, Inc. 
         [0016]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes third and fourth gear wheels  26  and  28 , respectively, mounted to frame  10  at second longitudinal side  10   b  of the frame for rotary movement relative to the frame. Third gear wheel  26  is mounted for rotation to frame  10  by first axle  16  and fourth gear  28  is mounted for rotation to frame  10  by second axle  18 . 
         [0017]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes a second endless track  30  having a plurality of magnetic sections  32  extending between and around third gear wheel  26  and fourth gear wheel  28  for movement parallel to second longitudinal side  10   b  of frame  10  as the third gear wheel and the fourth gear wheel undergo rotary movement. Second endless track  30  includes a second endless sprocket chain (not shown in the drawings) that is similar to first endless sprocket chain  24  of first endless track  20 , shown most clearly in  FIGS. 5 and 6 , that engages third gear wheel  26  and fourth gear wheel  28  and extends between and around the third and fourth gear wheels. Magnetic sections  32  of second endless track  30  are treads extending transverse to the direction of movement of the second endless track and are secured to move with the second endless sprocket chain in a way similar to the way magnetic sections  22  are secured to move with first endless sprocket chain  24 . Magnetic sections  32  can be formed of a rare earth material such as the special neodymium magnetic assembly sold by Magnetic Hold, Inc. 
         [0018]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes a first power source  34  mounted to frame  10  and a second power source  36  mounted to frame  10 . First power source  34  and second power  36  preferably are hydraulic motors of conventional construction and operation. 
         [0019]    In accordance with the present invention, first power source  34  is coupled to first endless track  20  by first coupling means to impart movement to first endless track  20 . For the particular embodiment of the present invention that is illustrated and being described, the first coupling means can be a gear train of conventional construction and operation that couples output shaft  34   a  of hydraulic motor  34  to first endless sprocket chain  24  of first endless track  20  by a sprocket  38 . 
         [0020]    In a similar manner, second power source  36  is coupled to second endless track  30  by second coupling means to impart movement to second endless track  30 . As with the first coupling means, the second coupling means can be a gear train of conventional construction and operation that couples output shaft  36   a  of hydraulic motor  36  to the second endless sprocket chain of second endless track  30  by a sprocket  40 . 
         [0021]    Hydraulic motors  34  and  36 , a plurality of fittings  42 ,  44 ,  46 , and  48 , and a remotely located high pressure fluid source  50  are parts of a closed loop hydraulic system. The remotely located high pressure fluid source  50  can be a pump of conventional construction and operation that delivers high pressure fluid (e.g., oil, air) to fittings  42  and  46  via hoses  52  and  56 , respectively, and receives return high pressure fluid from fittings  44  and  48  via hoses  54  and  58 , respectively. Fittings  42 ,  44 ,  48 , and  48  are hydraulically connected to hydraulic motors  34  and  36  by suitable means that are not shown in complete detail in the drawings but are well within the knowledge of those skilled in the art. 
         [0022]    A remotely located control station  60  controls activation and deactivation of hydraulic motors  34  and  36 . A plurality of valves  62 ,  64 ,  66 , and  68 , positioned in hoses  52 ,  54 ,  56 , and  58 , respectively, and located at the control station are controlled at the controlled station. High pressure fluid source  50  has two manually operated valves (not shown). One of these valves is opened to permit the supply of high pressure fluid from the high pressure fluid source to control station  60  via a hose  70  and the other of these valves is opened to permit the return of high pressure fluid to the high pressure fluid source via a hose  72 . The operation of valves  62 ,  64 ,  66 , and  68  is controlled at control station  60  by suitable means well-know to those skilled in the art. 
         [0023]    The pressurized liquid dispensing mobile unit operates in the following manner: 
         [0024]    When the pressurized liquid dispensing mobile unit is to move forward in a straight line, (1) equal levels of high pressure fluid from high pressure fluid source  50  are conducted from fittings  42  and  44  to hydraulic motors  34  and  36 , respectively, to cause the hydraulic motors to turn in a first direction, and (2) equal levels of high pressure fluid returned from hydraulic motors  34  and  36  are returned to high pressure fluid source  50  via fittings  46  and  48 , respectively. 
         [0025]    When the pressurized liquid dispensing mobile unit is to move backward in a straight line, (1) equal levels of high pressure fluid from high pressure fluid source  50  are conducted from fittings  46  and  48  to hydraulic motors  34  and  36 , respectively, to cause the hydraulic motors to turn in a second direction opposite from the first direction, and (2) equal levels of high pressure fluid returned from hydraulic motors  34  and  36  are returned to high pressure fluid source  50  via fittings  42  and  44 , respectively. 
         [0026]    When the pressurized liquid dispensing mobile unit is to move forward along a curved line, the operation is the same as with moving forward in a straight line, except the levels of high pressure fluid conducted to hydraulic motors  34  and  36  from valve fittings  42 ,  44 ,  46 , and  48  and returned to high pressure fluid source  50  from fittings  42 ,  44 ,  46 , and  48  are different and dependent upon the direction the pressurized liquid dispensing mobile unit is to take. 
         [0027]    When the pressurized liquid dispensing mobile unit is to move backward along a curved line, the operation is the same as with moving backward in a straight line, except the levels of high pressure fluid conducted to hydraulic motors  34  and  36  from fittings  42 ,  44 ,  46 , and  48  and returned to high pressure fluid source  50  from fittings  42 ,  44 ,  46 , and  48  are different and dependent upon the direction the pressurized liquid dispensing mobile is to take. 
         [0028]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes liquid supply means for supplying liquid under pressure. For the embodiment of the present invention that is illustrated and being described, liquid under pressure enters the pressurized liquid dispensing mobile unit via a fitting  74  that is connected to a remotely located high pressure water pump  76  by a hose  78 . A valve  80 , positioned in hose  78  and located at control station  60 , controls the delivery of liquid from high pressure water pump  76  to the pressurized liquid dispensing mobile unit. The operation of valve  80  is controlled at control station  60  by suitable means well-know to those skilled in the art. 
         [0029]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, also includes liquid dispensing means mounted for movement between a first closed position at which liquid is dispensed and a second open position at which liquid is not dispensed and an observer has an unobstructed view of and access to the liquid dispensing means. For the embodiment of the present invention that is illustrated and being described, the liquid dispensing means include a lid  82  hinged to frame  10  and an array  84  of individual nozzles  84   a - 84   f  mounted to lid  82  with each nozzle extending radially outward from a common point a selected distance, as shown most clearly in  FIG. 4 . The array  84  of spray nozzles, known to those skilled in the art as a spider array, can be a large diameter surface cleaning manifold, such as the A.M. Gatti, Inc., Type 3300. Spray nozzle array  84  is mounted to lid  82  for rotational movement relative to the lid. 
         [0030]    A pressurized liquid dispensing mobile unit, constructed in accordance with the present invention, further includes a third power source  86  mounted for movement with lid  82  and third coupling means for coupling third power source  86  to the spider spray  84  to impart rotary movement to the spider array. Third power source  86  preferably is a hydraulic motor of conventional construction and operation. For the particular embodiment of the present invention that is illustrated and being described, the third coupling means can be a pulley/belt unit (not shown) of conventional construction and operation that couples a pulley, mounted to the output shaft (not shown) of hydraulic motor  86 , to a pulley, mounted to the drive shaft  88  of spider array  84 , via a belt. 
         [0031]    Hydraulic motor  86 , a pair of fittings  90  and  92 , and high pressure fluid source  50  are parts of a closed loop hydraulic system. High pressure fluid source  50  delivers high pressure fluid to fitting  90  via a hose  94  and receives return high pressure fluid from fitting  92  via a hose  96 . Fittings  90  and  92  are hydraulically connected to hydraulic motor  86  by suitable means that are not shown in complete detail in the drawings but are well within the knowledge of those skilled in the art. 
         [0032]    Control station  60  controls activation and deactivation of hydraulic motor  86 . A pair of valves  98  and  100 , positioned in hoses  94  and  96 , respectively, and located at the control station are controlled at the control station. The operation of valves  98  and  100  is controlled at control  60  by suitable means well-known to those skilled in the art. 
         [0033]    Valves  98  and  100  selectively control activation and deactivation of hydraulic motor  86 , as well as the pressure level of the high pressure fluid delivered to hydraulic motor  86  and the pressure level of the high pressure fluid returned from hydraulic motor  86 , by controlling the passage of high pressure fluid from high pressure fluid source  50  to hydraulic motor  86  and the passage of high pressure fluid from hydraulic motor  86  to the high pressure fluid source. As high pressure fluid is delivered to hydraulic motor  86 , the hydraulic motor imparts rotary movement to spider array  84  and the surface on which the pressurized liquid dispensing mobile unit is mounted is cleaned by high pressure water emitted from the nozzles of the rotating spider array. 
         [0034]    As high pressure water, introduced via fitting  74 , is sprayed against a surface being cleaned, a vacuum is developed in the space between the pressurized liquid dispensing mobile unit and the surface being cleaned due to a seal between a flexible skirt  102 , mounted to frame  10 , and the surface being cleaned. The spray water and particulate matter removed from the surface being cleaned leave the pressurized liquid dispensing mobile through a vacuum port  104  and are deposited in a suitable container (not shown) for disposal. 
         [0035]    Among in the benefits derived from a pressurized liquid dispensing mobile unit constructed in accordance with the present invention is the facility of inspecting and maintaining the liquid dispensing means while the pressurized liquid dispensing mobile unit remains in place on a surface being cleaned. Instead of removing the pressurized liquid dispensing mobile unit from the surface being cleaned and moving it to another location to either inspect or maintain the liquid dispensing means, the operator of the equipment simply lifts lid  82  while the equipment is still held on the surface being cleaned and has an unobstructed view of the liquid dispensing means and unobstructed access to the liquid dispensing means should maintenance be necessary. 
         [0036]    The  FIG. 7  embodiment of the present invention differs from the  FIGS. 1-6  embodiment only by the substitution of a spray bar  106  as the nozzle array for the spider array  84  as the water spray component. Spray bar  106  can be the A.M. Gatti, Inc., 10″ Jet Spray Bar P/N 3743. As shown in  FIG. 7 , spray bar  106  has a plurality of nozzles  106   a - 106   f  disposed along the length of the spray bar. Spray bar  106  is mounted for rotary movement relative to lid  82  and rotary movement is imparted to the spray bar by a hydraulic motor, the output shaft of which is coupled to a drive shaft  108  of the spray bar. 
         [0037]    The foregoing illustrates some of the possibilities for practicing the invention. Many other embodiments are possible within the scope and spirit of the invention. It is, therefore, intended that the foregoing description be regarded as illustrative rather than limiting, and that the scope of the invention is given by the appended claims together with their full range of equivalents.