Abstract:
Fire hydrants which feature 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 valves which 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. Such valves preferably open, manually or automatically, when water is flowing from the water supply through the nozzle, a condition which renders it difficult at best to introduce toxins through the hydrant into a water supply, but close off portions of the barrel when the nozzle is open and water is not flowing through the nozzle.

Description:
This application is a continuation-in-part of U.S. patent application U.S. Ser. No. 10/309,646, entitled “Fire Hydrant With Second Valve” and filed Dec. 4, 2002 now U.S. Pat. No. 6,868,860 the entire contents of which are hereby incorporated by this reference. 

   RELATED FIELDS 
   Various aspects and embodiments of the present invention relate to fire hydrants which include additional valving 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. The nozzle is closed off by a threaded cap when the hydrant is not in use. The hydrant also includes a hydrant valve which controls flow of water from the water supply to and 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. 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 when the nozzle cap is attached, water pressure from the water supply would not force the toxins back out of the hydrant. 
   SUMMARY 
   One or more of various structures and embodiments according to the present invention may be introduced between the nozzle and the hydrant valve in order to make it more difficult or impossible to introduce toxins to a water supply through a fire hydrant. Structures such as valves according to various embodiments of the present invention permit flow of water when a nozzle is open and the hydrant valve is open, but prevent or substantially prevent flow of water through the valve and thus close off portions of the hydrant barrel when a nozzle is open but the hydrant valve is closed. 
   Valves or other structure according to various embodiments of the present invention are preferably introduced between the lowest nozzle in the hydrant and the main hydrant valve. They may form at least two general types: 
   (1) Valves which operate logically as an “and” gate to open only when both the hydrant valve and at least one nozzle is open but to be closed at all other times; and 
   (2) Valves which operate in concert with the hydrant valve. 
   Preferably, valves according to various embodiments of the present invention are located in the vicinity of the bottom of the lowest nozzle in the hydrant. 
   It is accordingly an object of various embodiments of the present invention to provide additional structure for fire hydrants in order to reduce the possibility of toxins being introduced into a water supply. 
   It is an additional object of various embodiments of the present invention to provide structures for retrofitting into fire hydrants in order to reduce the possibility of toxins being introduced into a water supply. 
   It is an additional object of various embodiments of the present invention to provide structure interposed between nozzles of fire hydrants and their hydrant valves, through which water actually flows when at least one nozzle and the hydrant valve is open. 
   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 
       FIG. 1  shows a cross section of one version of a conventional fire hydrant with nozzle cap removed and hydrant valve closed. 
       FIG. 2  shows toxins being introduced into the nozzle of the hydrant of  FIG. 1 . 
       FIG. 3  shows the cap replaced on the nozzle of 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 closed. 
       FIG. 5  shows toxins being introduced into a water supply as a result of the sequence shown in  FIGS. 1–4 . 
       FIG. 6  shows the hydrant of  FIG. 1 , which can be any conventional hydrant, which includes one embodiment of a second valve according to a preferred embodiment of the present invention. 
       FIG. 7  shows the second valve of  FIG. 6  opening as the nozzle cap is removed and the hydrant valve opened. 
       FIG. 8  shows the second valve open as water flows through the hydrant valve, the hydrant, the second valve, and the nozzle. 
       FIG. 9  shows a cross section of another embodiment of the present invention that includes a spherical secondary barrel insert. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a conventional fire hydrant  10 . Hydrant  10  typically includes a substantially vertical barrel  12  through which water may flow from a water main to a fire hose given certain circumstances as discussed generally below. At one end of the barrel  12  is a hydrant valve  14  which controllably interrupts fluid flow between a water supply  16  and the barrel  12 . At the upper end of the barrel  12  may be found a cap structure  18  which can include, for instance, a housing cover  20  and an operating nut  22  which rotates within the housing cover. The operating nut  22  includes threads which receive threads on an actuator rod  24  which in turn connects to the hydrant valve  14 . Not only does the cap structure  18  seal the top portion of the barrel  12  in waterproof fashion, but operating nut  22  may be used by fire fighters or others to open the hydrant valve  14  via actuator rod  24 . Hydrant  10  includes at least one nozzle  26  and can include more nozzles  26 . Each nozzle  26  may be closed with a cap  28  such as a threaded cap. The hydrant may also include breakaway structure such as a traffic feature  30 . 
   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  26 , usually in a threaded fashion after the cap  28  has been removed (See, e.g.,  FIG. 1 ). Then, after the hose is connected, operating nut  22  may be rotated with a wrench to cause actuator rod  24  to push down on relevant portions of hydrant valve  14  in order to open hydrant valve  14  (See, e.g.,  FIG. 4 ). When valve  14  opens, water flows from the water supply  16  through hydrant valve  14  through barrel  12 , out nozzle  26  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 according to various embodiments of the present invention became more apparent after that bellweather event, even if the 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  26  and the hydrant valve  14  can accommodate several gallons of liquid. Accordingly, as shown in  FIGS. 1–4 , a malefactor can unscrew cap  28  as shown in  FIG. 1 , introduce toxins as shown in  FIG. 2 , screw the cap back on as shown in  FIG. 3 , and open the hydrant valve  14  as shown in  FIG. 4 . When the nozzle  26  or all nozzles  26  are closed off and the valve opened, the liquid in the valve can communicate with liquid in the water supply  16  in order to foul the water supply  16  to the potential detriment of all those whose facilities are in communication with such water supply  16 . 
   Various structures according to various embodiments of the present invention prevent or reduce the possibility of such unworthy and direct reprobatory activity. Generally, various structures according to various embodiments of the present invention introduce physical structure between nozzle  26  and hydrant valve  14  through which water flows only when a nozzle  26  and hydrant valve  14  are open. Alternatively or in combination, such structure may close off portions of the barrel  12  below the nozzle  26  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  26  and opening the valve  14 . 
   According to a first embodiment shown in  FIGS. 6–8 , a second valve  32  according to the present invention operates in logical fashion as an and gate, the logical operands being at least partial openness of both the nozzle  26  and the hydrant valve  14  (or otherwise when water pressure is applied through the barrel  12  to nozzle  26 ) thus depriving miscreants or others the opportunity to introduce toxins into the hydrant  10 . 
   In the embodiment shown in  FIGS. 6–8 , second valve  32  includes a seat  34  which is mounted to barrel  12  preferably but not necessarily in a manner which allows valve  32  to be retrofitted to the hydrant  10 . A restriction member  36  cooperates with seat  34  to obstruct barrel  12  in waterproof or substantially waterproof fashion and thereby prevent or substantially prevent flow of water or other liquids upon certain conditions being met. In addition, the seat  34  and valve  32  close off portions of the barrel  12  to preclude or render more difficult introduction of toxins into the closed-off portions of the barrel  12 . In the embodiment shown in  FIGS. 6–8 , the valve  32  also includes an “O” ring  38  which helps form a seal between seat  34  and barrel  12 , on the one hand, and seat  35  and restriction member  36  on the other hand. 
   A biasing structure  40  can be disposed to bias the restriction member  36  against “O-ring”  38  and/or valve seat  34 . Biasing structure  40  may include any of the following, among others: any resilient member such as, for instance, including but not limited to a spring, any form of resilient material shaped or formed as desired, and/or a weight applied to restriction member  36  for biasing via gravity. As discussed below, biasing structure  40  may also include the actuator rod  24  if the restriction member  36  is coupled to the actuator rod  24  to travel in a manner corresponding to travel of rod  24  such as being mounted to rod  24 . 
   Restriction member  36  may be disc shaped to correspond generally to the inside surfaces of barrel  12 , and it may include a collar  42  to receive portions of rod  24  in sliding fashion or otherwise being connected to or mounted to rod  24 . 
   When nozzle cap  28  is removed and nozzle  26  is open, the restriction member  36  prevents or substantially prevents toxins or other liquid, solids or materials from being poured into the barrel  12  below the nozzle  26 . A reprobate, miscreant, villain or other unworthy type with ill will cannot push down on or puncture restriction member  36  to open up the barrel  12  according to restriction members  36  formed according to preferred embodiments of the invention which provide suitable resistance to deformation or destruction such as by screwdrivers, crow bars, or other implements employed on occasion by those with ill design or for other purposes. Such malefactory activity is prevented because the restriction member  36  closes off second valve  32  in all cases except where water is flowing outwardly from water supply  16  through nozzle  26 . 
   A logical table for operation of second valve  32  as shown in  FIGS. 6–8  is shown in Table 1 may be as follows, where “O” means “open” and “C” means closed: 
   
     
       
             
             
             
             
             
             
           
         
             
                 
               TABLE 1 
             
             
                 
                 
             
           
           
             
                 
               Hydrant 
               O 
               C 
               O 
               C 
             
             
                 
               Valve 
             
             
                 
               Nozzle 
               O 
               C 
               C 
               O 
             
             
                 
               Second Valve 
               O 
               C 
               C 
               C 
             
             
                 
               Flow from 
               Y 
               N 
               N 
               N 
             
             
                 
               water supply 
             
             
                 
               through 
             
             
                 
               nozzle 
             
             
                 
                 
             
           
        
       
     
   
   According to a second embodiment, restriction member  36  is mounted to rod  24  in order to move with rod  24 . In this embodiment, the restriction member  36  seats against bottom portions of valve seat  34  or an O-ring  38  interposed below valve seat  34  so that second valve  32  opens when and only when rod  24  moves down, which also means that hydrant valve  14  is opening. In this embodiment, the second valve  32  could, unlike the valve of embodiment one, at least theoretically open to some extent when hydrant valve  14  is open but nozzle  26  is closed. As a practical matter, that makes no difference since cap  28  is on the nozzle  26  preventing introduction of undesired materials into hydrant  10 . A logical diagram for embodiments of this type is shown in Table 2, the operands being at least partial opening of the hydrant valve and the nozzle respectively and again where “O” means “open” and “C” means closed: 
   
     
       
             
             
             
             
             
             
           
         
             
                 
               TABLE 2 
             
             
                 
                 
             
           
           
             
                 
               Hydrant 
               O 
               C 
               O 
               C 
             
             
                 
               Valve 
             
             
                 
               Nozzle 
               O 
               C 
               C 
               O 
             
             
                 
               Second Valve 
               O 
               C 
               O 
               C 
             
             
                 
               Flow from 
               Y 
               N 
               N 
               N 
             
             
                 
               water supply 
             
             
                 
               through 
             
             
                 
               nozzle 
             
             
                 
                 
             
           
        
       
     
   
   Any desired physical structure may be employed to accomplish the objective of meeting logical Tables 1 or 2 in order to produce or 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 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 restriction member and/or the seat, may be formed from iron and dipped in a liquid material, such as rubber or plastic, to coat the components. Alternatively, in some embodiments, iron components may be encapsulated in SBR rubber. Such processes may protect the iron components from corrosion or other types of decay. Such processes may also facilitate the seal between the restriction plate and the seat, potentially obviating the need for a separate gasket or o-ring. 
   O-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  40  may be formed of any desired material having requisite modulus of elasticity, durability, costs, and other properties. 
     FIG. 9  shows an alternative embodiment of various aspects and embodiments of the present invention that includes a spherical insert, the shape of which may facilitate the movement of water around the restriction member of the second valve when the second valve and the nozzle are in open conditions. The fire hydrant  42  shown in  FIG. 9 , much like previous embodiments of the present invention discussed above, may include a cap  44 , a barrel  46 , a nozzle  48 , an actuator rod  50 , a second valve  52  (including a biasing member  54 , a restriction member  56  and a seat  58 ) and a first valve  60 . Pin  68 , or any other suitable structure, may facilitate positioning the restriction member  56  with respect to the actuator rod  50 . The second valve  52  may act as a deterrent to the introduction of toxins into a water supply as described in the other embodiments above. 
   In the embodiment shown in  FIG. 9 , hydrant  42  also includes a secondary barrel insert  62 . Secondary barrel insert  62  may include a portion  64  with an enlarged diameter. Portion  64  may be located relative to second valve  52  such that when second valve  52  is in an open condition, restriction member  56  is at least partially located within portion  64 . The relatively large diameter of portion  64  may facilitate water flowing around restriction member  56 , up though barrel  46  and out nozzle  48 , when second valve  52 , nozzle  48  and first valve  60  are all open. In some embodiments, portions of the inner surfaces of secondary barrel  62  may be coated with epoxy. 
   Flanges  66  may facilitate retrofitting secondary barrel insert  62  into hydrant  42 . In some embodiments, flanges  66  may be chosen from a variety of split flanges such that secondary barrel  62  may be used with various fire hydrants having various flange configurations. In other embodiments, secondary barrel insert  62  is integral to the hydrant  42  and therefore does not require flanges  66 . 
   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.