document: CROSS REFERENCE TO RELATED APPLICATIONS 
         [0001]    This application is a divisional of and claims the benefit of U.S. patent application Ser. No. 10/396,619, filed Mar. 25, 2003, entitled “PLOW BLADE WITH WATER PASSAGEWAY.” 
       
      
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
         [0002]    Not Applicable 
         BACKGROUND OF THE INVENTION 
         [0003]    Many types of services are delivered to homes through conduits installed in relatively shallow underground trenches. These include telephone, television, natural gas, electricity, and drainage. These utilities are often installed with a plow.  FIG. 1  illustrates an example installation of a utility  20  with a prior art plowing process. A plow  30  is attached to a prime mover, typically a tractor  10 . The tractor  10  propels the plow through the ground. The plow  10  is relatively narrow and will split the ground open with a sharpened steel blade. The utility line  20  is introduced into the ground through a chute  40  that is attached to and directly behind the blade. The chute  40  holds the ground open as the utility line  20  is being fed into the desired vertical position and places the utility line  20  into a horizontal position at the desired depth under ground. 
           [0004]    An alternate configuration is illustrated in  FIG. 2  where the utility line  20  is laid out on the ground behind its intended position and then the plow  30  is connected to one end. The plow is then pulled through the ground in order to pull the utility line  20  into the correct position. In this configuration there is no chute. 
           [0005]    Depending on the desired depth, size of utility line, and the ground (soil) conditions (clay, sand, loam, etc.). This process may be slow and require a large amount of power from the tractor  10  to pull the blade/chute through the ground. To reduce this loading various efforts have been made to inject liquid to the plow and to the utility being installed to wet the ground. 
           [0006]    In some past designs the liquid was water, ejected in the direction of travel of the plow blade, and at the edge of the plow blade, utilizing the water to assist in the cutting action required to slice the ground. 
           [0007]    In other designs, useful for applications as illustrated in  FIG. 2 , the liquid has been water directed to the area around the utility line being pulled through the ground to lubricate and reduce the frictional drag. 
           [0008]    In still other designs water has been directed through long holes  36  drilled into the blade  34  of the plow  30 . Additional cross-drilled holes threaded to accept cooperating nozzles  38  are drilled near front edge  32 , as illustrated in  FIGS. 3 and 4 . Water was then pumped into inlet fitting  37  to route water to the sides of the plow. This design has proven successful as the lubrication provided by the water significantly reduces the power necessary to pull the plow. However this requires complicated manufacturing processes, with the result that a wear item, the blade, becomes a relatively expensive component. There exists a need for a blade to provide this water distribution in a manner, that is less expensive to initially manufacture and to maintain. 
         BRIEF SUMMARY OF THE INVENTION 
         [0009]    The present invention relates to a novel design for a plow blade which provides a fluid passage and points of fluid ejection which is produced with basic manufacturing processes allowing efficient production. 
           [0010]    Another aspect of the present invention is a blade construction including a multiple component assembly. This provides the ability to rebuild a blade, replacing a portion of the blade that may be worn. 
           [0011]    In another aspect of the present invention a process of ejecting a specific fluid at specific points along a plow blade the desirable characteristics are maximized, while the volume of ejected fluid is minimized. This method is adaptable in static plowing and vibratory plowing utilities. Lubricating the sides of the blade/chute that come into contact with the ground with fluid has been found to greatly reduce the amount of drag (friction). 
       
      
       
         BRIEF DESCRIPTION OF THE DRAWINGS  
           [0012]      FIG. 1  is a side view of a prior art tractor propelling a plow through the ground and installing a utility line that is being ejected through a chute attached to the plow; 
             [0013]      FIG. 2  is a side view of a prior art tractor propelling a plow through the ground and installing a utility that is being pulled through the ground and attached to the plow; 
             [0014]      FIG. 3  is side view of a prior art plow; 
             [0015]      FIG. 4  is cross section of the prior art plow taken along line  4 - 4  as illustrated in  FIG. 3 ; 
             [0016]      FIG. 5  is a side view of one embodiment of a plow constructed in a manner of the present invention; 
             [0017]      FIG. 6  is an isometric view of a portion of another embodiment of the plow of the present invention; 
             [0018]      FIG. 7  is a cross-section taken along plane  7 - 7  as illustrated in  FIG. 6 ; 
             [0019]      FIG. 8  is an isometric view of a front edge section; 
             [0020]      FIG. 9  is an isometric view of a portion of still another embodiment of the plow of the present invention; 
             [0021]      FIG. 10  is a cross-section taken along plane  10 - 10  as illustrated in  FIG. 9 ; 
             [0022]      FIG. 11  is a side view of another preferred embodiment of a plow constructed in a manner of the present invention; 
             [0023]      FIG. 11A  is an enlarged view of the part marked  11 A in  FIG. 11 ; 
             [0024]      FIG. 12  is a cross-section taken along plane  12 - 12  as illustrated in  FIG. 11 ; 
             [0025]      FIG. 13  is cross-section taken along plane  13 - 13  as illustrated in  FIG. 11 ; 
             [0026]      FIG. 14  is a partial cross-section taken along plane  13 - 13  as illustrated in  FIG. 11 : and 
             [0027]      FIG. 15  is a view like  FIG. 7  but showing an alternate embodiment with the void or channel formed in the blade instead of in the back of the front edge section. 
         
      
      
       DETAILED DESCRIPTION OF THE INVENTION  
         [0028]    Referring now to the drawings, like reference numerals designate identical or corresponding parts throughout the several views. The included drawings reflect the current preferred and alternate embodiments. There are many additional embodiments that may utilize the present invention. The drawings are not meant to include all such possible embodiments. 
           [0029]      FIG. 5  illustrates a plow  100  constructed according to the principles of the present invention. Plow  100  consists of blade  110 , leading edge sections  120 , point  130  and a fluid tube  140 . Chute  40  is attached to the rear edge  114  of blade  110 , and is constructed to receive and guide utility line  20  from above the ground to the desired depth where it is oriented generally parallel to the ground surface. In other embodiments, the chute may be replaced by a puller adapted to hold a utility line that is being pulled through the ground, similar to the arrangement shown in  FIG. 2 . 
           [0030]    The blade  110  further includes a front edge  112 , a top end  116  and a bottom end  118 . The top end  116  includes apertures  117  which will serve as attachment points, to adapt to a power unit. Many different types of power units can be used in conjunction with the preset invention. 
           [0031]    The bottom end  118  is adapted to support a variety of points  130 . The type of point to be installed may be dependent upon the soil conditions of a particular job. 
           [0032]    A component of the present invention is the manner in which the components are assembled to form flow paths for fluid to exit the blade at controlled locations and with a controlled flow rate. The flow paths of this first embodiment illustrated in  FIG. 1  are defined when the front edge  120  is attached to the blade  110 .  FIG. 8  illustrates a void  124  in surface  122  of leading edge section  120 . Fluid tube  140  is adapted to travel in void  124  to transfer pressurized fluid from the top of plow  100  into the void  124 , and may be sealed with weld  152  illustrated in  FIG. 6 . Other forms of sealing the connection between the tube  140  and the front edge sections  120  are possible, but are not illustrated herein as they are not a critical element of the present invention. Tube  140  has a top end  144  and a bottom end  146  and may extend into void  124  for any desired distance, as will be explained later. 
           [0033]    As illustrated in  FIGS. 6 and 7  the leading edge sections are attached to blade  110  with stitch welds  150 . Flow paths are defined by providing a small gap  154  between the front surface  112  of the blade and the rear surface  122 . The spaces between the stitch welds  150  results a flow path for the pressurized fluid, allowing fluid to pass from the void  124 , through the gap  154  between surfaces  122  and  112 , and out between the stitch welds  150 . In this manner, the location and length of the stitch welds  150  defines the location at which the fluid will exit the blade  110 . The gap  154  ( FIG. 7 ) between the surfaces  112  and  122  combined with the total amount of weld gap will define the volume at which the fluid will be ejected from the blade  110  at a certain fluid pressure. 
           [0034]      FIG. 15  shows an alternate arrangement of the  FIG. 7  structure, having the void or groove  224  formed in the front of the blade instead of having the void or groove  124  formed in the back of the leading edge section as shown in  FIG. 7 . 
           [0035]    The fluid pressure at a certain point along the blade&#39;s length will vary. If the tube  140  terminates at the top of blade  110 , the fluid pressure will be highest at that point and will decrease at points closer to the bottom. This is not ideal as there tends to be more resistance from the soils near the bottom of the blade, which requires the highest fluid pressure near that area. This is due to the types of soils typically encountered at lower depths. The surface soils typically include some percentage of organic matter, and higher percentage of air pockets: it is typically less dense. The soils encountered at points deeper can include the more difficult soils including clay. Thus there is an area, illustrated in  FIG. 5 , as a critical high friction area. This is the area in which the fluid is most critical. In order to assure that the fluid is ejected most aggressively in this area tube  140  can be extended so that it terminates at a position towards the bottom of this critical high friction area, the tube end  146  is located near the bottom end  118  of the blade  110 . The fluid pressure in void  124  will be highest at the point the tube terminates. In this manner the volume of fluid at this point can be maximized. 
           [0036]    In addition to varying the length of tube  140 , the number of leading edge sections  120  that are welded onto blade  110  can be varied to match the requirements of a specific job, including specific installation depths. The number of and location of the stitch welds can also be adjusted to tailor a plow  100  for a specific application. In this manner it is possible to provide a nearly infinite variety of configurations in an economic manner. 
           [0037]    Another embodiment is illustrated in  FIGS. 9 and 10 . In this configuration a manifold  160  is installed in between the blade  110  and the leading edge sections  120 . The manifold includes drilled holes  166  extending from a front side  164  to a rear side  162 , as illustrated in  FIG. 10 . The drilled holes  166  intersect at the middle, and when the leading edges  120  are installed onto the front side  164  the drilled holes  166  will terminate at the void  124  in the leading edge  120 . In this manner a flow path is defined by the void  124  and the holes  166  which will allow fluid to be routed from tube  140  to nozzles  168  that are installed at the rear side  162  of the manifold  160 . 
           [0038]    In this embodiment varying the nozzles  168  utilized in the assembly allows control of the flow rates and location of the fluid injection. The nozzles  168  can be replaced by plugs (not shown) if there are areas where fluid is not required, and the size of the nozzles  168  can be varied if the there are areas where extra flow is required. It provides a plow that can be modified using hand tools, without welding. 
           [0039]    Still another preferred embodiment is illustrated in  FIGS. 11 ,  11 A,  12  and  13 . In this embodiment the fluid tube  140  has been located on the opposite side of blade  110 , the rear side  114 . As can be seen in  FIG. 12  the fluid tube is located between the blade  110  and the chute  40 . In this configuration it is protected by plates  42 . The fluid tube includes an inlet fitting  142  at the top and travels to the bottom end  118  of blade  110  where it terminates at tube end  146 . The cross hatched portion shown in  FIG. 11A  represents a weld. 
           [0040]    Tube end  146  is adapted to attach to a bottom end section  126 , as illustrated in  FIG. 13 . Bottom end section  126  includes void  128  in the top side  127  as illustrated in  FIG. 14 . Tube  140  includes a bend that allows it to enter into void. The tube  140  is then sealed by welding it to the bottom end section  126  and the blade  110  with weld  156  such that the fluid is forced into void  128 . The bottom end section  126  is also welded to the blade  110  at the locations where it contacts the blade  110 , thus sealing the void  128 . 
           [0041]    Void  128  intersects void  124  at the bottom-front corner of blade  110 . At this point the fluid is transferred to void  124  and will flow along the front edge  112  of blade  110 . As described for the previous two embodiments, the fluid can then be allowed to travel to the edge of the blade and out to the soil either through a gap and spaces between stitch welds  150 , or through a manifold  160  between the front edge sections  120  and the blade  110 .  FIGS. 11 and 12  illustrate the use of the stitch welds  150  and gaps  151  between stitch welds  150 . However, the manifold  160  would work equally well. 
           [0042]    All the previously described embodiments provide a plow that can be tailored to provide fluid injection characteristics to match specific job requirements. The components are all manufactured with traditional manufacturing processes. The flow paths are defined by stacking together leading edge sections with flow voids, and welding or otherwise attaching them to a blade. This configuration provides appropriate function and provides an easily tailored configuration. 
           [0043]    Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
summary: A plow blade having a fluid passageway and points of fluid ejection is produced with basic manufacturing processes allowing for efficient production. The blade construction has a multiple component assembly for providing the ability to rebuild a blade and replacing a portion of the blade that may be worn. In another aspect of the invention a process of ejecting a specific fluid at specific points along a plow blade the desirable characteristics are maximized, while the volume of ejected fluid is minimized. This method is adaptable in static plowing and vibratory plowing utilities since lubricating the sides of the blade/chute that come into contact with the ground with fluid has been found to greatly reduce the amount of drag (friction).