Patent Publication Number: US-2013248015-A1

Title: Shut-Off Valve For Cisterns, Tanks and Similar

Description:
RELATED APPLICATIONS/PRIORITY BENEFIT CLAIM 
     This application claims the benefit of Italy Utility Model Application No. MI2012U000120, filed Mar. 23, 2012 by the same inventors (Artemio Velatta and Ruben Velatta), the entirety of which utility model application is hereby incorporated by reference. 
     FIELD 
     This invention refers generally to a shut-off valve for cisterns, tanks and similar. Specifically, this invention refers to shut-off valves, or gates, with heating elements, adapted for installation on cisterns or tanks transported or driven by articulated road vehicles and agricultural vehicles transporting liquid products, or used on cisterns or fixed tanks positioned outdoors. 
     BACKGROUND 
     Shut-off valves used on outdoor cisterns or tanks are typically hand-operated with a lever. On cisterns driven by articulated road vehicles and agricultural vehicles a valve, or gate valve, is installed, through which the product in the tanks is unloaded, generally in the liquid state, such as water and other substances. The valve includes one or more mobile gates that when necessary are lifted through the manual operation of a lever applied on the valve itself to open the valve and empty the product from the cistern or tank. 
     In farming, the valve is present on the so-called vacuum tankers that carry water or sewage-like fertilizers. 
     The use of such valves or gates on cisterns or tanks transported by vehicles feature a significant disadvantage related to the climate/environmental conditions in which these means operate. Specifically, ice forms inside these valves in case of very cold temperatures and due to liquid residues in contact with the seats of movable gates. Typically, these valves are exposed since they are fastened to a wall of the cisterns or tanks and are directly affected by atmospheric temperatures. The formation of ice easily blocks the gates and prevents the valve from opening when needed to unload the product. Action exerted with force on the lever of the valve to try to release the gates sometimes is not sufficient, and ice that forms inside the valve can cause breakages that can require the replacement of the valve itself. 
     To solve this problem, many devices have been conceived for application to the mentioned valves to heat their surface, with the result that heat is transmitted gradually inside the body by conduction to thaw the ice. One of these prior devices is formed of a rigid pipe, shaped to surround part of the valve. This pipe is fastened with screws or similar to the valve body and is fitted with opposed inlet and outlet orifices for liquid circulation, typically that of the cooling radiator of the vehicle&#39;s motor. This solution however has a few disadvantages, since this heat pipe element is applied to the outside of the valve. The application of the pipe to the valve body sometimes in fact requires quite complex interventions, which entail partial disassembly of the valve body itself to fasten the pipe with the previously removed screws or similar fasteners. Instead of the fastening with screws a connection can be made with welding, but this is a structural modification that requires time and entails additional costs. 
     Another disadvantage with the application of a heating pipe consists in that the pipe remains outside the valve body, so it is exposed to the risk of accidental shocks that could harm its integrity. To avoid this, the pipe should be particularly solid as a structure and this requirement brings about high costs. In addition, being outside the valve body, the pipe is directly affected by atmospheric temperature and the heat of the fluid circulating inside the pipe is wasted to a large extent without radiating inside the valve body itself, also because this pipe is not in direct contact with the valve body. This means that removing the ice that blocks the gate of the valve can require a long time, most of all if the vehicle remains for many hours outdoors in very cold temperatures. 
     BRIEF SUMMARY 
     The aim of this invention is to solve the above-mentioned disadvantages. Specifically, the aim of this invention is to provide a shut-off valve that, to remove the ice that forms inside it, does not require having an additional component fastened to its exterior. 
     Another aim of the invention is to provide a valve as defined above in which ice removal inside is fast and efficient and without a noteworthy heat loss from the heating fluid. Another aim of the invention is to provide the users with a shut-off valve for cisterns, tanks and similar, apt to guarantee a high level of long-lasting resistance and reliability, such as to be easily and cost-effectively made. 
     These aims and others are reached with a shut-off valve for cisterns, tanks and similar of this invention, specifically for cisterns and tanks transported or driven by articulated road vehicles and agricultural vehicles, comprising a metallic body with an upper mouth as well as opposed inlet and outlet fluid spouts, with two paired gates connected between them and operated by lifting and lowering and comprising the shut off means for the fluid, and characterized mainly in that the shut off valve includes a duct formed at least partially around the body from which it is hydraulically independent and that exits or terminates in opposed holes or openings formed on respective and integral extensions of the duct, the duct being made jointly with the said valve body upon its forming. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Manufacturing and functional characteristics of the shut-off valve for cisterns, tanks and similar of this invention can be further understood in the following detailed description, that refers to the attached drawings that represent a preferred form embodiment and in which: 
         FIG. 1  represents schematically, in a perspective view, the shut-off valve of this invention; 
         FIG. 2  is an additional schematic perspective, according to a different angle, of the same valve; 
         FIG. 3  represents schematically a view from the lower or bottom end of the valve itself; 
         FIG. 4  is a longitudinal section, along line A-A of  FIG. 3 , of the same valve; 
         FIG. 5  represents schematically a longitudinal section of the same valve, highlighting one part of the lever that handles fluid shut-off means; 
         FIG. 6  is a longitudinal section along line B-B of  FIG. 5  of the same valve. 
     
    
    
     DETAILED DESCRIPTION 
     With initial reference to  FIGS. 1 and 2 , the shut-off valve of this invention, indicated generally with  10 , includes a metallic body  12  with a substantially ovoid profile, whose opposed front and back faces define respective flattened surfaces  14 ,  16  on each of which a cantilevered circular opening  29  is formed delimited by a ring nut or hexagonal nut  18 . The openings  29  delimited by nuts  18  form respective inlet and outlet mouths for the fluid contained in the cistern, tank or similar. In body  12  of valve  10  are located the shut off means for this fluid, outlined in  FIG. 6  and composed of two paired gates  22  connected between the openings  29  and lifted and lowered through a lever in conventional fashion. This lever is outlined partially with  24  in  FIG. 5  and includes a hinged arm on one end at the centre of the gates  22  and, on the other end, connected to an external operating lever (not illustrated). The through hole indicated with  26  in  FIG. 2 , made on either the front or back face  14  or  16  of body  12 , forms the pull-in seat for this operating lever. The upper part of valve  10  defines a mouth  28  closed after by a plug  46 . 
     According to the invention, in body  12  of valve  10  an integral duct  30  is made that wraps at least partially the valve body  12  itself as best shown in  FIG. 4 , following the ovoid valve body profile along the side wall of the valve body from bottom to top, beginning with its lower arched-convex portion corresponding to the lower half of the circular fluid inlet and outlet openings  29 . As shown in  FIG. 3 , the duct  30  also extends from front to back across the valve body side wall between opposite circular openings  29  delimited by ring nuts or nuts  18 . The duct  30 , outlined specifically in  FIGS. 4 and 5 , is formed by casting during the forming of valve  10  and develops peripherally to the valve body itself without fluid communication with the valve interior; i.e., the duct  30  is hydraulically independent or sealed relative to the valve body interior. As best shown in  FIG. 4 , the side wall  12 ′ of the valve body forms the inner wall or surface of duct  30 . Specifically, according to a preferred form of embodiment, duct  30  embraces almost the entire lower half part of body  12  corresponding to the lower half of the fluid inlet and outlet openings  29  ( FIG. 4 ), and extends upwardly on at least one of its flanks or sides along side wall  12 ′ until reaching a point proximate the edge of upper mouth  28 . 
     The opposed ends of duct  30 , which follows at least in part the perimeter of body  12  of valve  10 , exit in respective integral extensions  32 , typically with circular section, which form, with respective openings  34  and  36 , the inlet and outlet points for the heated fluid circulating through the duct itself. This fluid can come from the cooling radiator of the vehicle, shown schematically in  FIG. 4 , on which a cistern or a tank is placed with a shut-off valve  10  of this invention. 
     Along duct  30 , which encloses at least part of the perimeter of body  12 , another integral threaded extension is made, indicated with  40 , which encloses an opening  42  located in the lower part of the valve body. The opening  42 , which is closed by a conventional removable threaded plug (shown schematically in phantom), constitutes a point of entrance and of periodic inspection of duct  30 , for any removal from the duct itself of solid residues that could progressively reduce its cross-section, thus reducing the efficiency of the heating flow supplied therein. 
     The duct  30  directly overlies wall  12 ′ of body  12 , providing a direct radiating effect from the hot fluid in the duct to the interior of the valve body itself through the common wall  12 ′. Consequently the ice formed inside body  12  thaws faster, with a consequent fast restoration of mobility of gates  22  whose lifting allows the outflow of liquids or sewage contained in the cistern or tank. The outlet of these liquids is made, as acknowledged, by connecting a hose to the mouth delimited by one of the flanges or nuts  18 . The fluid circulating in the duct  30  can come from the cooling circuit of the motor of the vehicle, as specified above, or alternately from other on-vehicle or off-vehicle circuits in which there is a cooling liquid, or a liquid specifically heated. 
     As can be understood from the above, the advantages of the invention are clear. The shut-off valve of this invention allows fast thawing of the ice, if any, formed inside the valve, thanks to duct  30  formed integrally with body  12  and directly in touch with the valve body along the full length of the side wall  12 ′ common to both the valve body and the duct. This duct, being integral to body  12 , is adequately protected against shocks, and, furthermore, it is perfectly harmonized with the configuration of the body itself, without highlighting the presence of foreign elements. In addition, with the valve of this invention, traditional disadvantages due to the need to install a specifically fitted pipe on the body of the valve are avoided. 
     An additional advantage is the ability to easily inspect the duct  30 , cleaning the duct if necessary through hole  42  created in the lower part of body  12 . Though the invention was described above with special focus on one of its forms of embodiment, by way of example but not restrictive, many modifications and variations will be evident to a technician skilled in the art thanks to the above description. This invention, therefore, aims at embracing all modifications and variations that are within the spirit and the protective framework of the following claims. 
     It should further be understood that to the extent the term “invention” is used in the written specification, it is not to be construed as a limiting term as to number of claimed or disclosed inventions or discoveries or the scope of any such invention or discovery, but as a term which has long been conveniently and widely used to describe new and useful improvements in science and the useful arts. The scope of the invention should accordingly be construed by what the above disclosure teaches and suggests to those skilled in the art, and by any claims that the above disclosure supports in this application or in any other application claiming priority to this application.