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CROSS REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation-in-part of U.S. patent Ser. No. 11/372,947, titled “Breathable Fire Hydrant Rod,” filed Mar. 9, 2006, which is a continuation-in-part of U.S. Pat. No. 7,055,544, titled “Fire Hydrant With Second Valve,” filed Nov. 23, 2004, which is a continuation-in-part of U.S. Pat. No. 6,868,860, titled “Fire Hydrant With Second Valve,” filed Dec. 4, 2002, the entire contents of each of which are hereby incorporated by this reference. 

   FIELD OF THE INVENTION 
   Various aspects and embodiments of the present invention relate to retrofitting fire hydrants with a replacement hydrant body having additional valves in order to render more difficult the task of introducing toxins into a water supply. 
   BACKGROUND 
   Conventional fire hydrants offer access to a municipal water supply in a manner in which operatives with ill intent may appreciate. Briefly, conventional fire hydrants include at least one nozzle for coupling to a fire hose. A threaded cap closes off the nozzle when the hydrant is not in use. The hydrant also includes a hydrant valve which controls flow of water from the water supply through the hydrant, through the nozzle, and into the fire hose. 
   Conventionally, the barrel of the hydrant between the nozzle and the hydrant valve, which is in the lower portion of the hydrant, accommodates several gallons of fluid or solids. Accordingly, it is possible to unscrew a nozzle cap, introduce gallons of toxin, reattach the nozzle cap, and open the hydrant valve to allow the toxins to communicate with and flow, by gravity and perhaps at least to some extent by Bernoulli&#39;s principle, into the municipal water supply, since water pressure from the water supply can not force the toxins back out of the hydrant because the nozzle cap is attached. 
   An example of a system and method for preventing toxins from being introduced to a water supply through a hydrant is described in U.S. Pat. No. 6,868,860, entitled “Fire Hydrant With Second Valve,” the entire contents of which are hereby incorporated by this reference. In some examples described in U.S. Pat. No. 6,868,860, a valve structure is introduced between the nozzle and the primary valve that makes it more difficult or impossible to introduce toxins into a water supply through a fire hydrant. The valve structure prevents or substantially prevents the flow of water through the hydrant upon certain conditions and closes off portions of the hydrant barrel when a nozzle is open but the hydrant valve is closed. Generally, the valve structure can include a seat, a restriction member, and a biasing structure. 
   Retrofitting fire hydrants with secondary valves may be accomplished by removing the hydrant barrel, inserting the secondary valve and affixing the seat to the hydrant body with an adhesive or mechanical means, such as a screw. While this is an effective method for installing the secondary valve, another method is needed to retrofit a fire hydrant with the secondary valve. For example, retrofitting hydrants that include an off-centered actuator rod or a different shaped barrel, such as triangular or cone can be relatively difficult and, in some cases, impossible. 
   SUMMARY OF THE INVENTION 
   One or more various structures and embodiments according to the present invention may be utilized to retrofit a fire hydrant with a replacement hydrant body containing an additional valve in order to provide a retrofitting process capable of being applied to a wide range of different hydrant configurations. A structure such as the replacement hydrant body may allow quick installation of an additional valve in a fire hydrant to close off portions of the hydrant barrel when the hydrant valve is closed to prevent the introduction of toxins into a lower barrel portion. 
   According to some embodiments of the present invention, a replacement hydrant body can be introduced between the cap structure and the primary valve during installation. For example, the hydrant body may be detached from the cap structure and a lower portion of the hydrant, such as at a breakaway structure or primary valve, and a replacement hydrant body, containing a primary valve, can be installed. 
   According to various aspects and embodiments of the present invention, the replacement hydrant body may include a secondary valve, a weeping valve, and a breathable stem. The secondary valve may include valve seat, a restriction member, and a biasing structure. During installation of a replacement hydrant body, the hydrant body may be removed and the replacement body, containing the secondary valve, installed in its place. In some embodiments of the present invention, the replacement body may include a globe containing the secondary valve. In other embodiments, the replacement body does not include a globe. 
   It is an object of some embodiments of the present invention to provide a replacement structure having a secondary valve and adapted to be retrofitted into existing fire hydrants in order to reduce the possibility of toxins being introduced into a water supply and provide a quick and efficient method to retrofit existing hydrants with a secondary valve. 
   It is an additional object of some embodiments of the present invention to provide a replacement structure having a secondary valve and adapted to be quickly installed into a fire hydrant. 
   It is an additional object of some embodiments of the present invention to provide more efficient drainage of liquids inside the hydrant barrel in order to reduce the possibility of hydrant freezing. 
   It is an additional object of some embodiments of the present invention to provide a secondary valve structure capable of restricting the flow of water in the hydrant barrel upon certain conditions. 
   Other objects, features, and advantages of various embodiments of the present invention will become apparent with respect to the remainder of this document. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a cross-sectional view of a conventional fire hydrant. 
       FIG. 2  shows toxins being introduced into the hydrant of  FIG. 1 . 
       FIG. 3  shows a nozzle cap replaced on the hydrant of  FIG. 1  after toxins have been introduced. 
       FIG. 4  shows opening of the hydrant valve of the hydrant of  FIG. 1  after toxins have been introduced and the nozzle cap replaced. 
       FIG. 5  shows toxins being introduced into a water supply through the hydrant of  FIG. 1 . 
       FIG. 6  is a cross-sectional view of a hydrant that has been retrofitted with a secondary valve according to one embodiment of the present invention. 
       FIG. 7  shows a hydrant body being detached in a retrofit process according to one embodiment of the present invention. 
       FIG. 8  shows a replacement hydrant body being installed according to one embodiment of the present invention. 
       FIG. 9  shows a hydrant with an installed replacement hydrant body according to one embodiment of the present invention. 
       FIG. 10  shows the hydrant of  FIG. 9  in normal operation. 
       FIG. 11  shows another embodiment of replacing a portion of the hydrant body according to one embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a conventional fire hydrant  10 . Hydrant  10  typically includes a hydrant body  11  which consists of a substantially vertical barrel. Water may flow through barrel  12  from a water main  16  to a fire hose given certain circumstances as discussed generally below. At one end of the barrel  12  is a primary hydrant valve  18 , which controllably interrupts fluid flow between the water supply  16  and the barrel  12 . At the upper end of the barrel  12  may be found a cap structure  20  which can include, for instance, a housing cover  22  and an operating nut  24  which rotates within the housing cover  22 . The operating nut  24  includes threads, which receive threads on an actuator rod  26 , which in turn connects to the primary hydrant valve  18 . Not only does the cap structure  20  seal the top portion of the barrel  12  to prevent the flow of water, but operating nut  24  may be used by fire fighters or others to open the primary hydrant valve  18  via actuator rod  26 . Hydrant  10  includes at least one nozzle  28  and can include more nozzles. Each nozzle may be closed with a cap such as threaded cap  30 . The hydrant may also include breakaway structure such as a traffic feature  32 . 
   In normal operation, the hydrant  10  may be employed as follows to help fight fires, provide refreshing summer breaks for overheated urban citizens and/or their offspring, participants in road races, or for other purposes or beneficiaries. First, a hose (not shown) may be connected to nozzle  28 , usually in a threaded fashion after the cap  30  has been removed. Then, after the hose is connected, operating nut  24  may be rotated with a wrench, or other tool, to cause actuator rod  26  to push down on relevant portions of primary hydrant valve  18  in order to open primary hydrant valve  18 . When the primary valve  18  opens, water flows from the water supply  16  through primary hydrant valve  18  and barrel  12 , out nozzle  28  into the hose and accordingly toward its desired application or destination. 
   However, hydrant  10  may also be the subject of attention from miscreants who have the temerity to attempt to introduce toxins into a public water supply. Such concerns have heightened since the date known as “9-11” (Sep. 11, 2001) when terrorists activities became the focus of heightened concern. Accordingly, the need for structures to prevent such attempts became more apparent after that bellweather event, even if they were foreseen by the inventor named in this document beforehand. More particularly, a person with ill design can attempt to introduce toxins into a water supply  16  taking advantage of the fact that the barrel  12  of a hydrant  10  between the nozzle  28  and the primary hydrant valve  18  can accommodate several gallons of liquid or solid material and, for some toxins, as little as 0.05 quart can detrimentally affect a water supply. Accordingly, as shown in  FIGS. 2-5 , a malefactor can unscrew the nozzle cap  30  as shown in  FIG. 1 , introduce toxins as shown in  FIG. 2 , screw the nozzle cap  30  back on as shown in  FIG. 3 , and open the primary hydrant valve  18  as shown in  FIG. 4 . When the nozzle  28  or all nozzles are closed off and the primary valve  18  opened, the liquid or solid toxins in the barrel  12  can communicate with liquid in the water supply  16  in order to foul the water supply  16 , as shown in  FIG. 5 , to the potential detriment of all those whose facilities are in communication with such water supply  16 . 
   A physical structure may be introduced between nozzle  28  and primary hydrant valve  18  that allows water or other fluid to flow only when nozzle  28  and primary hydrant valve  18  are open. Alternatively, or in combination, such structure may close off portions of the barrel  12  below the nozzle  28  in order to deprive miscreants of at least a portion, if not all, of the space available into which to load toxins before closing the nozzle  28  and opening the valve  18 . 
   An example of such a physical structure is shown in  FIG. 6  as a secondary valve  102  contained in hydrant  100 . The hydrant  100  may be an existing hydrant that has been retrofitted to include a replacement hydrant barrel portion  118  that includes a secondary valve  102  according to various embodiments of the present invention. The replacement hydrant barrel portion  118  may also include a enlarged diameter portion  104 . The enlarged diameter portion  104  can accommodate or otherwise contain the secondary valve  102 . The secondary valve  102  may include a seat  106 , a restriction member  108  and a biasing structure  110 . The seat  106  can be the lower portion of the enlarged diameter portion  104  or a separate structure (not shown) attached to a hydrant barrel  112 . The biasing structure  110  is adapted to apply a force on restriction member  108  to form a seal with the seat  106  and at least one gasket  114  to prevent liquids or solids from reaching a lower portion of the hydrant  116  below the secondary valve  102 . Examples of gasket  114  include a quad ring and an O-ring. 
   Secondary valve  102  may preferably be any shape to correspond generally to the inside surfaces of the hydrant  100 . For example, the secondary valve  102  may be disc-shaped, rectangle, square, or any size and shape in order to cooperate with the seat  106  to obstruct the flow of water. The biasing structure  110  can be disposed to bias the restriction member  108  against gasket  114  and/or seat  106 . Biasing structure  110  may include any of the following, among others: any resilient member such as, for instance, a spring, any form of resilient material shaped or formed as desired, and/or a weight applied to restriction member  108  for biasing via gravity. A restriction platform  111  may be included and is adapted to cooperate with biasing structure  110  to bias the restriction member  108  against seat  106  to close off communication between portions of the hydrant  100  above secondary valve  102  and portions below secondary valve  102 . 
   The hydrant  100  also includes the primary valve  18  to controllably allow water to flow from the water supply  16  via actuator rod  26  and operating nut  24  and the cap structure  20  to close off an end of a hydrant  100 . When the primary valve  18  is opened, the secondary valve  102  can also open, either from water pressure from water supply  16  or by moving with the actuator rod  26 . 
   In one embodiment of the present invention, the hydrant  100  in  FIG. 6  has been retrofitted with the secondary valve  102  by installing the replacement hydrant body  118  that is a portion of the hydrant  100 . The replacement hydrant body  118  may include the secondary valve  100  disposed in the enlarged diameter portion  104  and a replacement nozzle  120  and replacement nozzle cap  122 . In some embodiments, the original nozzle may be reattached to the replacement hydrant body  118  instead of include the replacement nozzle  120 . In some embodiments, the original nozzle cap may be reattached to the replacement hydrant body  118  instead of including the replacement nozzle cap  122 . The replacement hydrant body  118 , as described in more detail below, may be installed by detaching the original or existing hydrant body and replacing it with the replacement hydrant body  118 . 
   A retrofitting process according to one embodiment of the present invention is shown in  FIGS. 7-10 . The process may begin with an existing hydrant  200  as described above with reference to  FIGS. 1-5 . The existing fire hydrant  200 , shown in  FIG. 7 , can include a hydrant body  202  that is connected to a cap structure  204  and a breakaway structure, such as traffic feature  206 . The hydrant body  202  may include one or more nozzles, such as nozzle  206 . The hydrant body  202  may be essentially hollow and allow at least a portion of an actuator rod  210  to traverse at least a portion of the hollow area of the hydrant body  202 . The actuator rod  210  may have a first end  212  that is connected to the cap structure  204  and a second end  214  that is connected to a primary valve  216 . A portion of the actuator rod  210  may include a detachable portion  218  at the traffic feature  206 , such that the actuator rod  210  can include a first portion  220  above the traffic feature  206  and a second portion  222  below the traffic feature. In some embodiments, actuator rod  210  may be located essentially in the center of hydrant body  202 . In other embodiments, actuator rod  210  may be located close to, or essentially adjacent to, 
     FIG. 7  shows one embodiment of a hydrant body  202  being detached from the remaining portions of the hydrant  200  in preparation for installing a replacement hydrant body with a secondary valve. The hydrant body  202  can be detached from the cap structure  204 , such as by using a tool to remove bolts  224  or by otherwise disengaging any structure that connects the hydrant body  202  to the cap structure  204 . Similarly, the hydrant body  202  can be detached from the traffic feature  206 , using a tool to remove bolts  226  or other structure that is connecting the hydrant body  202  to the remaining portions of the hydrant  200 . 
   In some embodiments, the actuator rod first portion  220  may be disconnected from the actuator rod second portion  222  to detach the cap structure  204  from the rest of the hydrant  200 . Additionally or alternatively, the actuator rod  210 , in some embodiments, may be disconnected from the cap structure  204 . The actuator rod  210  can be removed from the hydrant during some retrofitting processes and a replacement actuator rod can be provided in its place. 
   After detaching the hydrant body  202 , a replacement hydrant body may be provided, such as replacement hydrant body  240  shown in  FIG. 8 . The replacement hydrant body  240  includes a secondary valve  242  and, in some embodiments, may include a replacement nozzle  244 , a replacement nozzle cap  246 , and an enlarged diameter structure  248 . The enlarged diameter structure  248  can contain the secondary valve  242 . In a replacement hydrant body that does not include an enlarged diameter structure, portions of the secondary valve  242  may be affixed to an inner wall of the replacement hydrant body. 
   The replacement hydrant body  240  may be attached to the remaining portions of the hydrant  200  by using a tool, or otherwise, to connect the cap structure  204  and traffic feature  206  to the replacement hydrant body  240 . In some embodiments, the actuator rod first portion  220  may be reconnected to the actuator rod second portion  222  and/or the actuator rod  210  may be reconnected to the cap structure  204 . After connecting the replacement hydrant body  240 , an assembled hydrant, as shown in  FIG. 9 , may be formed. 
   The replacement hydrant body  240 , according to some embodiments, may optionally include a check valve  250  above the secondary valve  242 , and a pump-out valve  252  below the secondary valve  242 . After using hydrant  200  via normal operation, some water may become trapped within the hydrant  200  above the secondary valve  242 . In some climates where hydrants are used, water that remains in those hydrants can, over time, damage the hydrant by freezing or evaporating creating pressure on the internal hydrant components. The check valve  250  can be optionally included in replacement hydrant body  240  to allow water that may remain in the hydrant  200  after use to drain out of the portion of the hydrant  200  above the secondary valve  242 . Check valves according to some embodiments of the invention may be conventional check valves that allow fluids to flow one way, such as out of the hydrant  200 , but prevent fluids or other materials from flowing other ways, such as from outside of the hydrant  200 . 
   Hydrant  200  may also include a weep hole  254  located near a primary valve  216  to allow fluids trapped in hydrant  200  below the secondary valve  242  and above the primary valve  216  to exit the hydrant. As stated above, water remaining in hydrants may damage internal hydrant components due to changing form after exposure to certain temperatures and/or pressures. The weep hole  254  allows the water to be released from the hydrant and prevents, or substantially diminishes, the possibility of water remaining in the hydrant  200  after use. 
   The weep hole  254 , however, must be properly maintained to allow it to properly release water remaining in the hydrant  200  after use. In some applications of hydrant  200 , persons responsible for maintaining the hydrant may fail to ensure the weep hole  254  is functioning properly. For example, the weep hole  254  may become plugged or otherwise blocked, thereby preventing water from leaving the hydrant via weep hole  254 . Previous methods to combat a plugged weep hole included inserting a hose through a hydrant nozzle to pump the water out or inserting anti-freeze or some other chemical into the hydrant after use to prevent or reduce liquids freezing in the hydrant. Such methods, however, may unknowingly introduce toxins into the water supply or otherwise contaminant the water supply through the hydrant. Replacement hydrant bodies, such as replacement hydrant body  240 , may include the pump-out valve  252  to facilitate removal of water that may become trapped in the area of the in hydrant  200  below the secondary valve  242  and above the primary valve  216  to exit the hydrant, even if the weep hole  254  fails to function properly. The pump-out valve  252  may be a check valve that can pump water out of the area of the hydrant  200  below the secondary valve  242  and above the primary valve  216  and not require the insertion of hoses or chemicals to prevent water remaining in the hydrant  200  after use. 
   In some embodiments of the present invention, a breathable stem (not shown) may be included with the replacement hydrant body  240 . The breathable stem may allow air from the area above the secondary valve  242  to reach the portion of the hydrant  200  below the secondary valve  242 . The breathable stem may facilitate water removal via the weep hole  254  or pump-out valve  252  by allowing air to reach the area of the hydrant below the secondary valve and decrease a likelihood that a vacuum might form in that area. The breathable stem can also include a check valve to prevent fluids or solids from flowing toward the primary valve  216 . 
   After installation, the hydrant  200  includes the secondary valve  242  to prevent toxins from being introduced into the water supply through the hydrant  200 . The hydrant  200  can resume normal operation, as shown in  FIG. 10 . The replacement nozzle cap  246  is removed and an operating nut  258  is rotated causing the actuator rod  204  to open the primary valve  216  and secondary valve  242  and allowing water from the water supply  16  to exit the hydrant  200  through replacement nozzle  244 . 
   Replacement hydrant bodies according to various embodiments of the present invention may be any sized or shaped structure adapted to replace at least a portion of an existing hydrant and contain a secondary valve. For example, some replacement hydrant bodies may not include a hydrant nozzle and only replace a portion of the hydrant below the nozzle and above the primary valve. Other replacement hydrant bodies may be configured to replace the entire hydrant structure between a hydrant cap structure and a water supply conduit.  FIG. 11  shows one embodiment of a hydrant  300  with a replacement hydrant body  302  that includes a secondary valve  304 , a replacement nozzle  306 , and a breakaway structure  308 . The replacement hydrant body  302  is adapted to be installed between a cap structure  310  and water supply conduit  312 . For example, and as shown in  FIG. 11 , a hydrant body extending between the cap structure  310  and the water supply conduit  312  has been removed and the replacement hydrant body  302  is about to be connected to the cap structure  310  and water supply conduit  312 . The replacement hydrant body  302  may be connected to the cap structure  310  and water supply conduit  312  using bolts or other attachment structure. 
   Any desired physical structure may be employed in order to provide a replacement hydrant portion with a structure to preclude introduction of undesired materials into fire hydrants. Components of embodiments according to the present invention are preferably durable materials but may be of any desired material. It is conventional for many components of fire hydrants to be cast iron, bronze, and at least some or all of metallic components of structures according to various embodiments of the present invention may be formed of bronze or other conventional or even unconventional materials. For example, in some embodiments, at least some of the components, such as the replacement hydrant body, secondary valve and/or the seat, may be formed from iron and dipped in, plated, or coated with a liquid material, such as rubber, plastic, or metal such as nickel. Alternatively, in some embodiments, iron components may be encapsulated in SBR rubber or powder coated. Such processes may protect the iron components from corrosion or other types of decay. Such processes may also facilitate the seal between the valve and the seat, potentially obviating the need for a separate gasket. 
   O-rings or quad rings may be formed of conventional materials used in fire hydrants, or unconventional materials. Suitable resilient structures such as springs which may form biasing structures may be formed of any desired material having requisite modulus of elasticity, durability, costs, and other properties. 
   Modifications, adaptations, changes, deletions, and additions may be made to various embodiments of the present invention as disclosed in this document without departing from the scope or spirit of the invention.

Summary:
The present invention relates to methods and devices for retrofitting fire hydrants with additional structure for reducing the potential that those with ill intent can foul municipal water supplies by introducing toxins or other materials into fire hydrants. Various embodiments include a replacement hydrant body having an enlarged diameter portion that can be installed to replace an existing hydrant body. The replacement hydrant body can include a secondary valve comprising a seat, biasing structure, and a restriction member to close off portions of the hydrant otherwise available for receipt of toxic or other materials when the fire hydrant nozzle cap is unscrewed and open.