Abstract:
A pipe cleaning tool comprises a rod slidably retained in a housing. Means for affixing the housing to a pipe in the area of the blockage are provided so that, when affixed, the rod slides through the housing and through the blocked pipe. The end of the rod is pushed into and through the blockage, allowing free flow of fluid through the pipe to resume. A blowout port on the housing is in fluid communication with a rod bore in the housing through which the rod slides so that, when the blockage is removed, fluid flows out through the rod bore and out the blowout port. Fluid flowing out through the blowout port can then be controlled and directed by coupling a hose to the blowout port. The pipe cleaning tool is particularly useful to remove blockages in the test cocks of backflow prevention valves.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to a tool for removing obstructions in pipes through which fluid flows and, more particularly, to a device for cleaning out test cocks of backflow prevention valves through which pressurized water flows into a facility.  
       BACKGROUND OF THE INVENTION  
       [0002]     The supply of public water to industrial facilities is and has long been a necessity for progress and efficient manufacturing and production. In addition, the need to provide a means for treating and discharging waste water used by industrial facilities has also been a concern, not only to allow the industry to run efficiently, but also because of safety concerns about the dangers of releasing contaminated wastewater into the environment.  
         [0003]     Significant environmental regulations have been implemented to insure the safety and necessity of waste water treatment to protect the health of citizens whose water might be contaminated. Only recently have federal and local governments and regulatory agencies begun to recognize the necessity for also insuring that contamination does not get into the water supply through water inlet lines. To that end, many governments and regulatory authorities have begun to require the installation of backflow prevention valves in industrial facilities that protect against contamination of the public water supply by preventing industrial, or other, wastewater from “backflowing” out through the incoming line. In the case of a loss of pressure in the public supply, such as occurs during water main breaks or during utility line repair work, a loss of pressure at the incoming water line could result in industrial process water being pushed back out through the inlet. When pressure is restored, the industrial process water contaminating the water supply is pushed downstream to subsequent users. Backflow prevention valves have only recently begun to be mandated to prevent such occurrence.  
         [0004]     As with any other technology, backflow prevention valves can only serve their purpose if they are properly maintained and operable. Thus, part of many of the laws and regulations compelling the installation and use of backflow prevention valves are requirements that the backflow prevention valves are periodically tested, typically annually, to make sure they are operating properly. While a boon to maintenance personnel whose job it is to insure proper operation and regulatory compliance, the testing of backflow prevention valves has proven to present at least one annoying problem to those maintaining them. Because of the infrequency with which the valves are operated (often they will go an entire year between tests without ever being operated), parts are worn out quickly and, significantly for purposes of the present invention, blockages resulting from sediment build-up or, most frequently, calcium deposits, can result in smaller areas of the backflow prevention valve through which the supply water flows. The problem associated with blockages formed from calcium deposits is particularly acute in the test cocks of backflow prevention valves. Typical backflow prevention valves such as that shown in U.S. Pat. No. 6,325,090 have four test cocks to which a valve tester is attached to check and confirm proper operation of the backflow prevention valves. By attaching three test hoses of a tester alternately at the four test cocks positioned on both sides of the two check valves in a backflow prevention valve, such as that shown in U.S. Pat. No. 5,566,704, proper operation of the backflow prevention valve can be checked.  
         [0005]     A problem that typically arises, however, is that the test cocks, mounted on the side of the backflow prevention valves, are a prime spot for the collection of calcium deposits. It is axiomatic that, if the test cocks are blocked, the tester, which relies on fluid flow under pressure through the test cock, will be useless.  
         [0006]     Thus, it has become common practice for plumbers responsible for checking for the proper operation of backflow prevention valves to first “clean out” the test cock before attaching the tester. This “clean out” is difficult because the plumber must depress a piston while shoving a rigid wire down through the test cock. He knows he has been successful when water comes spraying out the test cock, which is the second problem. The plumber and his paperwork (data must be recorded for regulatory compliance) can get soaked in the process of cleaning out just one backflow prevention valve. To make matters worse, backflow prevention valves are typically difficult to access, coming in to an individual facility above ground so that the plumber is required to be on a ladder to “clean out” the test cocks and check operation of the backflow prevention valve.  
         [0007]     There is thus identified a need for a tool that is portable and which may quickly and easily be attached to test cocks on backflow prevention valves that removes blockages therein allowing maintenance personnel to test the operation of the backflow prevention valve without getting wet from the fluid spray when the blockage is removed.  
       OBJECTS OF THE INVENTION  
       [0008]     It is an object of the present invention to provide a pipe cleaning tool that is portable and which may be quickly attached to and removed from a pipe such that a clean out rod can be moved through the pipe to break up sedimentary blockage therein.  
         [0009]     It is another object of the present invention to provide a pipe cleaning tool having visible indication provisions to let maintenance personnel working on the pipe know when the blockage has been cleared.  
         [0010]     It is yet another object of the present invention to provide a pipe cleaning device having a blowout port allowing fluid to be directed therefrom into a discharge receptacle.  
         [0011]     It is a further object of the present invention to provide a pipe cleaning device having a blowout port allowing fluid to be discharged and directed away from the maintenance personnel using the device.  
         [0012]     It is a further object of the present invention to provide a test cock cleanout device that attaches to the test cock and removes blockage therein while also indicating to the user when the blockage has been removed.  
         [0013]     It is yet another object of the present invention to provide a test cock cleanout device for use with backflow prevention valves that is installed in-line with a valve tester.  
         [0014]     These and other objects and advantages of the present invention will be apparent from a review of the following specification and accompanying drawings.  
       SUMMARY OF THE INVENTION  
       [0015]     The present invention comprises a pipe cleaning tool comprising a housing and a rod slidably positioned in the housing. A means for retaining the rod in the housing is provided in the preferred embodiment, as well as a means for affixing the housing to a pipe whereby a cleaning end of the rod is free to slide into and out of the pipe, breaking up sediment and calcium deposits in so doing.  
         [0016]     The cleanout rod has a circular cross section and the housing has a corresponding cylindrical bore through it of slightly greater diameter than the circular cross section of the rod. The means for affixing the housing to a pipe is adjacent to a first end of the cylindrical bore, which extends completely through the housing to define a second, opposed, end of the cylindrical bore. The rod is of sufficient length to extend completely through the cylindrical bore and out both ends of the housing.  
         [0017]     The rod, which predominately is present in the housing, with only ends sticking out, comprises a handle end and a cleaning end. When the rod is properly positioned in the housing, the cleaning end extends from one end of the cylindrical bore and the handle end extends from the other end of the cylindrical bore.  
         [0018]     A means for sealing the cylindrical bore around the handle end is provided so that, when the blockage is removed, fluid does not spray the user. The housing is also provided with a blow out port which is in fluid communication with the cylindrical bore. The blow out port is utilized by connecting to it a means for directing fluid, provided in the most preferred embodiment by a flexible hose and means for connecting the hose to blow out port, which directs fluid exiting the blowout port into a discharge receptacle.  
         [0019]     It is contemplated that the pipe cleaning tool of the present invention may be used by being attached to a test cock and the blockage blown out through a flexible hose, as set forth above, but it also is provided with means for inserting the tool in-line with a valve tester, comprising means for securing a test hose of the tester to the blow out port. A means for securing a test hose to the blow out port is provided comprising a fitting having an externally threaded nipple sized to engage an internally threaded coupling affixed to said test hose.  
         [0020]     The preferred embodiment of the pipe cleaning tool of the present invention is provided with a shoulder mounted on the rod, adjacent to the cleaning end, the shoulder having a larger cross section than the circular cross section of the rod, and a stepped down length of the cylindrical bore in the housing that is smaller than the shoulder on the rod, defining the means for retaining the rod in the housing. Another feature important to retaining the rod in the housing is a handle affixed to one end of the rod exterior to the housing.  
         [0021]     The present invention is also a test cock cleanout device comprising a housing, a rod slidably mounted in the housing, means for retaining the rod in the housing, and a means for affixing the housing to a test cock whereby a cleaning end of the rod is free to slide through the test cock. The means for affixing is more particularly described as an externally threaded extension of the housing received by an internally threaded test cock, and, further, may include a bushing inserted into the test cock, the bushing having external threads to engage the internally threaded test cock and internal threads to be engaged by the externally threaded extension.  
         [0022]     The test cock cleanout device of the present invention also includes means for indicating flow through the test cock cleanout device. In the preferred embodiment, the means for indicating comprises a bore in the housing, the bore being sized such that the rod is free to move therein. The fluid under pressure in the test cock travels through the bore and out through a blowout port in said housing, where it is visually indicated to the user that the blockage has been removed.  
         [0023]     The test cock cleanout device of the present invention is alternatively described as a housing, a movable member retained in the housing, means for moving the movable member through the test cock to engage and break through blockage, means for visually confirming that the blockage has been removed. Specifically, a bore in the housing is in fluid communication with a test cock and a blow out port in the housing in fluid communication with the bore.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is a perspective view of the pipe cleaning tool of the present invention.  
         [0025]      FIG. 2  is a schematic representation of a typical backflow prevention valve and tester.  
         [0026]      FIG. 2A  is a partial view illustrating the connections between the backflow prevention valve and tester.  
         [0027]      FIG. 3  is a sectional view of the housing of the present invention.  
         [0028]     FIGS.  4  is a side view of the cleanout rod of the present invention separate and apart from the housing.  
         [0029]      FIG. 5  is a side view of the test cock cleanout device of the present invention illustrating the blowout port in the housing.  
         [0030]      FIG. 6  is a schematic representation of the test cock cleanout device of the present invention secured to a test cock of a backflow prevention valve, with flow out of the blowout port directed into a receptacle.  
         [0031]      FIG. 7  is a schematic representation of the test cock cleanout device of the present invention attached in-line with a tester so that the test cock cleanout device does not have to be removed to allow use of the tester. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0032]     The pipe cleaning tool  10  of the present invention, depicted in  FIG. 1 , comprises a housing  12  and a rod  14  which is positioned within the housing  12  but is free to move relative to the housing  12  in the direction shown. An operator uses the pipe cleaning tool  10  by attaching an end  20  of the housing  12  to a pipe and sliding the rod  14  back and forth, through the housing  12  to allow the cleaning end  18  of the rod  14  to engage and break through sediment, calcium deposits, or other blockages in the pipe to be cleaned. In the most preferred embodiment, the operator manually grabs the handle  16  and alternately pushes and pulls the rod  14  through the housing  12 . The pipe cleaning tool  10  of the present invention is particularly well suited to being used to clean out short lengths of pipe such as test cocks installed to allow testing and operation of valve components, or gage cocks installed to allow monitoring of fluid flow, pressure, temperature.  
         [0033]     One specific use of the test cock cleanout device  10  of the present invention is in association with a backflow prevention valve  30  (see  FIG. 2 ). In practice, the backflow prevention valve operates to prevent backflow, in the direction indicated, through the use of two check valves  32 ,  34 . The check valves  32 ,  34  are biased open by the incoming public water supply and allow flow through the backflow prevention valve  30  to provide incoming water to a user.  
         [0034]     The backflow prevention valve  30  depicted in  FIG. 2  is typical and, in many jurisdictions and districts, required for industrial uses of water. By allowing water to flow in only one direction, the backflow prevention valve operates to keep water from being pushed from the user end  36  as backflow through the valve  30  if pressure is lost on the supply side  38  of the valve. While generally infrequent, supply side pressure may be lost in the event of a water main break or if maintenance work is being done on the line nearby.  
         [0035]     Backflow prevention valve  30  is typical of a compulsory valve, not only through its use of two check valves  32 ,  34 , but also by its inclusion of four test cocks  40 A,  40 B,  40 C,  40 D. In addition to requiring installation of backflow prevention valves, statutes and regulatory authorities generally also define a required maintenance check up period, typically a year, during which the backflow prevention valve  30  must be checked and operated. A tester  50  (see  FIG. 2 ) is used for that purpose, as follows. A low pressure hose  52  and a high pressure hose  54 , along with a pressure supply hose  56 , are alternately attached to the test cocks  40 A,  40 B,  40 C and  40 D, and pressure applied to actuate the operation of the check valves  32 ,  34 . The tester also includes on/off ball valves  58 ,  60  to allow isolation of the low hose  52 , high hose  54  and supply hose  56 . Finally, the tester  50  includes a pressure meter  62  which monitors the pressure at which the check valves  32 ,  34  operate. It is the value gleaned from the pressure meter  62  that must be recorded, and which must be compliant with laws and regulations. Typically an operator will manually record the necessary pressure data from an analog meter, such as that shown in  FIG. 2 , although digital meters providing an automatic printout are also known in the prior art.  
         [0036]     The tester  50  is attached to the test cocks  40 A,  40 B,  40 C,  40 D by internally threaded caps  64 ,  66 ,  68  secured to the ends of the low hose  52 , the high hose  54 , and the supply hose  56 . The caps  64 ,  66 ,  68  are secured to the test cocks  40 A,  40 B,  40 C,  40 D, which are also internally threaded, through the use of fittings or bushings  70 , as shown in  FIG. 2 . By carrying fittings of many different sizes, a single tester  50  can be adapted to a wide array of test cock sizes by merely changing the fittings. Depending on the size of the incoming supply and the backflow prevention valve therein, the test cocks  40 A,  40 B,  40 C,  40 D may range in size from ⅜ inches to 1.5 inches.  
         [0037]      FIG. 2A  depicts the low hose  72  and high hose  74  as being coupled to two test cocks  76 ,  78  of a backflow prevention valve  82 , through the use of fittings  84 ,  86 , shown in  FIG. 2A . A schematically depicted blockage  80  in test cock  76  is illustrative of the problem inherent in backflow prevention valves; if a test cock is clogged, the tester  50  will be useless to ascertain relative high and low pressures or to properly operate the backflow prevention valve  30 .  
         [0038]     Environmental regulations and state and federal law mandate the use and periodic testing of a backflow prevention valve  30 . Often, though, the annual maintenance and operation of the check valves  32 ,  34  is the only time the backflow prevention valve  30  is operated. In a year&#39;s time, significant amounts of calcium deposits and sediment builds up in the test cocks  40 A,  40 B,  40 C,  40 D of a backflow prevention valve. This build up prevents the accurate assessment of the backflow prevention valve because, as depicted in  FIG. 2A , blockage  80  in the test cock  76  will result in a false pressure reading at the low hose  72 .  
         [0039]     Prior to the present invention, maintenance personnel charged with checking the operation of a backflow prevention valve  30  would manually force a piece of rigid wire down into the test cocks  40 A,  40 B,  40 C,  40 D to break apart any blockage therein. Once the blockage was pierced, typically the line pressure blows out the remaining blockage, along with supply water. The result is generally a soggy service man and paperwork from the spray of four test cocks on each backflow prevention valve.  
         [0040]     The most preferred embodiment of the present invention comprises a test cock cleanout device  10  comprising a housing  12  and a rod  14  slidably positioned within a bore  100  formed within the housing  12 . When a first end  13  of the housing  12  is attached to a test cock  90  (see  FIG. 6 ), the cleaning end  92  of the rod  14  is moved back and forth through the test cock  90  (as indicated by the arrow in  FIG. 6 ). In this way, any blockage in the test cock  90  is broken up by the cleaning end  92  of the rod  14  and, under water pressure in the backflow prevention valve, either pushed out through the system or out through the test cock  90 .  
         [0041]     In the most preferred embodiment, the test cock cleanout device  10  also comprises a blowout port  96  in fluid communication with the bore  100  formed in the housing  12  (see  FIG. 5 ). The blowout port  96  itself comprises a bore in the housing  12  which intersects the bore  100  through which the rod  14  travels, such that fluid under pressure in the test cock  90  will be expelled through the bore  100  and out the blowout port  96 .  
         [0042]     Insofar as the bore  100  in the housing  12  is larger than the rod  14 , when the housing  12  is attached to the test cock  90 , as soon as the blockage is removed from the test cock  90  fluid under pressure flows up through the bore  100  and out the blowout port  96 . In this way, the operator gets instant visual confirmation that the blockage has in fact been removed and that flow through the test cock  90  has been effected. While a simple means of visual confirmation, seeing water expelled from the blowout port  96  is critical to the principles of the present invention, because it prevents a user of a test cock cleanout device  10  from attaching the housing  12  to the test cock, pushing the handle  16  down to force the cleaning end  92  into the test cock  90 , removing the test cock cleanout device  10  from the test cock, and attaching the tester  50 , only to find that he needs to repeat the use of the test cock cleanout device  10 . Other means of visual confirmation can be used and are specifically contemplated by the principles of the present invention, such that the use of a flowmeter, pressure meter, or visible window will all suffice to provide the necessary visual confirmation of blockage removal.  
         [0043]     The means for attaching the housing  12  to a pipe or test cock, such as shown in  FIG. 6 , is provided by external threads  102  on the housing  12 . In the most preferred embodiment of the present invention, the threaded extension  104  is ⅜ inch, to accommodate the majority of internally threaded test cocks without requiring the use of a fitting. To accommodate larger test cocks, a bushing between the threaded extension  104  and the test cock is utilized to secure the housing  12  thereto.  
         [0044]     The test cock cleanout device  10  of the present invention may be utilized two different ways. First, it may be attached to a test cock  90  and the cleaning end  92  of the rod  14  is pushed into the test cock  90  until fluid flow of the blowout port  96  (and attached fitting  106  and flexible hose  108  in  FIG. 6 ) is detected. At that point, the test cock cleanout device  10  is detached and similar cleanout procedures are done for the remaining test cocks, and the tester is then systematically attached across the test cocks, now blockage free, of the backflow prevention device to confirm proper operation in compliance with the law and regulatory guidelines. If used in this manner, the test cock cleanout device  10  has a fitting  106  installed in the blowout port  96  with a flexible length of hose  108  affixed thereto that allows the user to direct the fluid expelled under pressure into a discharge receptacle such as a bucket  110  ( FIG. 6 ).  
         [0045]     The test cock cleanout device  10  of the present invention may also be used by being attached to a test cock  120  while having a fitting  122  in the blowout port  96  that is appropriately sized (typically ⅜ inch) to engage an internally threaded cap  123  of a backflow prevention valve tester  124 . The test cock cleanout device  10  may thus be used to remove blockage in the test cock  120  and then left in-line with the tester  124 . In this arrangement, the operator gets visual confirmation of the blockage removal by seeing the change in pressure at the tester  124 .  
         [0046]     Means for retaining the rod  14  in the housing  12  are provided by bore  100  through the housing  12  having a first end  130  and a second end  132 . In the most preferred embodiment of the present invention, a smaller diameter bore  134  is formed the length of the housing  12 , and then a larger diameter bore  136  is formed concentrically to the smaller bore  134 . The result is a step down in bore size from the larger bore  136  to the smaller bore  134 , creating an annular surface  140 . Similarly, the rod  14  is provided with a coordinated and inverted step up shoulder  141  adjacent to the cleaning end of the rod  92  extending from the first end  13  of the housing. The shoulder  141  is formed as a result of a smaller cross section at the handle end  142  of the rod compared to the larger cross section at the cleaning end  92  of the rod  14 . That is, the cleaning end  92  of the rod  14  has a greater diameter than the opposite handle end of the rod  142 , and the rod  14  is rigid so that the rod shoulder  141  is larger than the reduced bore  134 . As the rod  14  is pulled up into the housing  12 , it is free to move until the shoulder  141  contacts the annular surface  140  between the larger bore  136  and smaller bore  134 . This feature is particularly important because, as the cleaning end  92  of the rod pushes through sediment blockage in the test cock, the fluid under pressure in the test cock will act to push the rod  14  outwardly. The means for retaining the rod  14  in the housing  12  provided by the rod shoulder  141  and bore annular surface  140  prevents the rod  12  from being blown out of the housing  12 , while still allowing free movement of the rod  14  within the housing  12 .  
         [0047]     It is specifically contemplated that other elements and features may be used to retain the rod  14  in the housing  12  as well, including without limitation, raised lips on the rod  12 , inwardly extending protuberances in a single bore, etc. The means for retaining the rod  14  in the housing  12  is the coordinated relationship between overlapping elements on the rod  14  and housing  12  which restrict the travel of the rod  14  through the housing in a direction away from the test cock.  
         [0048]     The means for retaining the rod  14  within the housing  12  further comprises elements for restricting the travel of the rod  14  into the second end  15  of the housing  12  in the direction of the test cock. In the most preferred embodiment, a handle  16  is provided at handle end  150  of the rod  14 . The handle  16  is securely affixed to the smaller end  150  of the rod  14  and is large enough that it will not pass through the smaller bore  134  in the housing  12 . The handle  16  snaps onto rod  14  and includes gripping provisions to prevent separation in the most preferred embodiment, but mechanical fixture devices such as a bolt extending through the handle  16  and rod  14  or adhesive, are specifically contemplated and do not depart from the principles of the present invention.  
         [0049]     In the most preferred embodiment, a cap  152  is provided at the second end of the housing opposite to the first end  13  attaching to the test cock, and provides a means for sealing the cylindrical bore  134 . A circular opening  156  in the cap  152  is provided to allow clearance for the narrower cross section  142  of the rod  14  while the outer surface  158  restricts the travel of the rod  14  into the housing  12 . The cap  152  has interior threads  160  which cooperate with exterior threads  162  on the second end  15  of the handle  14  to tighten the cap  152  down onto the handle  14 . A circular O-ring  164  is inserted between the cap  152  and handle  14  (see  FIG. 3 ) to seal off the bore  134  and prevent fluid from exiting out through the cap  152 .  
         [0050]     The handle  16  is rigid and shaped to accommodate a user&#39;s manual operation of grabbing the handle  16  and pushing and pulling the rod  14  through the housing  12  to move the cleaning end  92  through the test cock being cleaned out. The means for retaining the rod  14  in the housing  12  provided by the handle  16  and outer surface  158  of the cap  152  are intended to be illustrative and not restrictive, and other devices and elements providing similar mechanical restrictions preventing the rod  14  from being pushed too far into the housing  12  are specifically contemplated and do not depart from the principles of the present invention.  
         [0051]     The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described in order to best illustrate the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.