Waterpipe freeze detector
United States Patent 1191 Wismer Apr. 29, 1975 1 1 WATERPIPE FREEZE DETECTOR [76&#39;] Inventor: Otto H. Wismer, El Mirage Star Rt..  
 Box 134, Adelanto. Calif. 92301 22; Filed: Jan. 21, 1974 21 Appl. No.: 435,261  
 [52] US. Cl. 137/60; 137/429; 251/75 [51] Int. Cl E03b 7/12 [58} Field of Search 137/59-62, 137/429; 123/41.14; 236/100 [56] References Cited UNITED STATES PATENTS 956.062 4/1910 Fell 137/60 1.526.718 2/1925 Opp 137/60 X 1,971,459 8/1934 McGuire 137/60 2/1968 Allderdice .1 137/62 3.380.464 4/1968 Arterbury et a1. ..l 137/60 FOREIGN PATENTS OR APPLICATIONS 1009,809 3/1 952 France 137/62 Primary Examiner-Martin P. Schwadron Assistant E.\&#39;aminerRichard Gerard Attorney. Agent, or FirmAllen A. Dicke, Jr.  
 [57] ABSTRACT A water-containing chamber having a closed bottom is exposed to ambient temperatures. A loosely fitted piston at the top of the chamber is raised, as ice crystals form in the chamber. Raising the piston through a snap action device opens a valve which inhibits freezing of adjacent water-containing pipes by permitting water to flow out therethrough.  
 6 Claims, 4 Drawing Figures .WATERPIPE FREEZE DETECTOR BACKGROUND country which are subjected to freezing weather, care i is taken in the installation of the water system to locate the waterpipe in zones which are not subjected to frost conditions; however, occasionally there is need for location of a pipe in a cold environment, such as an outside faucet.  
  In other sections of the country, cold is not particularly severe or enduring and, in those circumstances, water systems are installed without consideration of freezing problems; however a considerable number of these systems are subject to short periods of freezing for which they are not designed. Thus, there is need for a device to detect freezing conditions and act to prevent damage. The closest known prior art is Browne U.S. Pat. No. 382,588. This patent is directed to a device which detects outside temperatures and permits water flow when temperature decreases to a predetermined point.  
 SUMMARY In order to aid in the understanding of this invention, it can be stated in essentially summary form that it is directed to a water-freeze detector. The freeze detector comprises an upwardly-directed closed bottom vessel for containing water. A piston is positioned in the upper part of the vessel at the top opening thereof and spaced from the bottom of the vessel so that freezing of water in the vessel causes expanding ice crystals to act upon the piston. Response means is connected to the piston to indicate water-freezing conditions.  
  It is thus an object of this invention to provide a water-freeze detector which relies upon ice crystal expansion to cause response to freezing conditions. It is another object to provide a freeze detector which is particularly useful for the detection of freeze in waterpipes so that action can be made to prevent waterpipe damage. It is a further object to provide a waterpipe freeze detector which is economical of construction and of reliable, trouble-free use so that it may be installed to protect household waterpipes from freezing.  
  Other objects and advantages of this invention will become apparent from a study of the following portion of the specification, the claims, and the attached drawings.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side-elevational view of the waterpipe freeze detector of this invention shown in the waterline leading to a house.  
 supply pipe 14 to a house or other water utilization structure 16. A portion of the water supply pipe 14 is exposed to the exterior ambient environment. In other casesythe water supply pipe 14 may be underground, or otherwise protected, and a portion of it would extend from the house 16, as for example, to an outside faucet.  
  In the preferred embodiment of the device, freeze detector 10 has body 18 which has male exterior pipe threads 20 thereon. These threads permit the body to be screwed into the bottom opening of a downwardlydirected tee 12 which is in series in the waterline. Thus the upper face 22 of the body is in contact or exposed to water in the waterline.  
  Vessel 24 is downwardly-directed from body 18 and has a closed bottom 26. At its upper end, it is open to the upper face 22. Positioned within vessel 24 adjacent its upper end is piston 28. Piston 28 does not reach closed bottom 26 but, in the preferred embodiment illustrated, extends only about halfway to the closed bottom. Piston 28 is tubular and its upper end is flared at 30 to prevent the piston from sliding downward in the vessel. The bottom end of piston 28 is closed, but ports 32 in the sidewalls of piston 28 adjacent its lower end permit communication from the tubular interior of the piston to the interior of vessel 24. The upper end of piston 28 is open to face 22. This structure is such that. in normal use, piston 28 and vessel 24 is filled with water, and the volume 34 of the vessel below the piston is subjected to ambient conditions. When these conditions are such that the severity of frost will cause waterline freezing, first the water in volume 34 freezes. The growth of ice crystals in this volume causes upthrust of piston 28.  
  Bleed tube 36 is connected between the upper face 22 and the exterior ambient. Bleed tube 36 is provided with bleed tube valve 38 which closes the top of the bleed tube andprevents bleed of water from the line FIG. 2 is a side-elevational view of the preferred em- DESCRIPTION FIG. 1 illustrates the waterpipe freeze detector 10 in its preferred usage. It is mounted in a tee 12 in a water out of the bleed tube. Bleed tube valve 38 is in the form of a lever 40 pivoted at 42. Lever 44 is positioned over the top end of piston 28 and is pivoted at 46. Toggle spring 48 interconnects the two toggle levers and has its center line passing below the pivots to urge both levers downward; however, when expanding ice crystals in volume 34 force piston 28 upward, this motion moves the spring centerline above the line of pivots 42 and 46 to cause an opening force to open bleed tube valve 38. Spring 48 is sufficiently strong to open the valve. In cases of particularly high water pressure, a pilot valve or balanced poppet valve can be used to reduce the bleed valve operating force. Spring 50 urges lever 44 downward so that, as ice melts in volume 34, piston 28 can descend and toggle spring 44 can pass below the line of pivots 42 and 46. Thus toggle spring 48 holds valve 38 closed after the ice is melted in the sensing volume. Except for spring 50, the toggle spring 48 would hold valve 38 open until manually reset; however spring 50 provides for automatic reset upon detection of detector volume 34 of sufficient warming of the exterior to cause sufficient melting to permit piston 28 to fall back to its normal, warm-detecting position.  
  Bleed tube 36 can be equipped with alternative flow control structures. First of all, tube 36 can be of such diameter as to provide the desired flow. Second, it can be provided with a valve which can be manually and exteriorly adjusted so that different amounts of flow can be achieved by manual selection, depending upon the depth of frost. Third, a temperature-sensitive valve can be employed so that, with deeper frost, more water is permitted to flow. It is well known that permitting water to flow inhibits pipe freezing, both by bringing heat into the area by mass transfer and by providing motion to the water, which inhibits the formation of solid ice. Thus the waterpipe freeze detector automatically permits bleed water flow, when sufficient frost conditions to cause ice crystallization in volume 34 are encountered. This protects the waterpipe 14 against plugging or bursting by freezing.  
  This invention having been described in its preferred embodiment, it is clear that it is susceptible to numerous modifications and embodiments within the ability of those skilled in the art and without the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims.  
 What is claimed is:  
 1. A water-freeze detector comprising:  
 a body;  
 a vessel mounted on said body, said vessel having a closed bottom and an open top for connection to a water supply line for filling with water from the water supply line;  
 a piston movably mounted with respect to said vessel adjacent the open top of said vessel and spaced from the closed bottom of said vessel to define a freeze volume, said piston having port means therein to vent said freeze volume out of the top of said vessel so that water from the water supply line fills said freeze volume and exposure of said vessel to freezing ambient causes the freezing of water within said vessel to raise said piston with respect to said vessel;  
 bleed passage through said body, a valve in said bleed passage to control the flow of water from the water supplyline through said body and a snap action device interconnected between said piston and said valve so that upon raising of said piston within 2. The freeze detector of claim 1 wherein said vesselis a substantially upright cylindrical tube and said piston extends partway down into said tube to be guided by said tube.  
  3. Thefreeze&#39;detector of claim 2 wherein said piston is tubular and has a closed bottom and a flared top, said port means comprising ports in the sides of said tubular piston adjacent its closed bottom so that said vessel is in communication with the interior of said tubular piston, said flared top of said piston engaging at the open top of said vessel.  
  4. The freeze detector of claim 1 wherein said body comprises a male pipe-threaded body for threading into a waterline tee, said valve comprising a poppet valve spring-urged to the open position upon piston motion.  
  5. The freeze detector of claim 1 wherein said snap action interconnection between said piston and said valve comprises a first lever and a second lever, said first lever and said second lever each being pivoted with respect to said body, a spring interconnecting said first lever and second lever so that, when said spring is positioned below said lever pivots, the levers are urged downwardly, said first lever overlying said piston and said second lever being connected to said valve so that when said piston rises due to freezing in said freeze volume, said first lever is raised so that said spring is positioned above said pivots and said spring causes said second lever to rise to open said valve.  
  6. The water freeze detector of claim 5 further including a second spring, said second spring being connected between said body and said first lever to urge said first lever downward so that, upon thawing of ice in said freeze volume, said piston is thrust downward into said vessel and said said first mentioned spring is moved below said lever pivots to snap said valve closed.