Abstract:
The various embodiments disclosed and pictured herein illustrate a liquid vacuum apparatus and method that is easy to operate, provides increased safety for operators, mitigates the risk of operator exposure to the liquid, and mitigates the risk of liquid spillage during and after the liquid is transported. As described herein, the liquid vacuum apparatus may be employed either with or without the connector, piping, and end piece; and if an end piece is used, it may take many different forms depending on the particular application.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    Applicant, Gary Drew, a United States Citizen residing in Maquoketa, Iowa, claims priority under 35 U.S.C. §119(e) of provisional U.S. Patent Application Ser. No. 60,931,641 filed on May 24, 2007 which is incorporated by reference herein. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates to an apparatus and method for removing liquid from a liquid container. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0003]    No federal funds were used to develop or create the invention disclosed and described in the patent application. 
       REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX 
       [0004]    Not Applicable 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention provides for an efficient, sanitary, and safe means of removing liquids from a liquid container. More specifically, exemplary embodiments of the present invention provide an apparatus for evacuating used oil from an oil-type food fryer while minimizing the operator exposure to the oil and the likelihood of spillage during transfer of the oil. 
         [0006]    The liquid vacuum apparatus employs a vacuum pump  2  in fluid communication with a storage tank  1 . The vacuum pump  2  operates to create an atmosphere within the storage tank  1  with a pressure below that of ambient pressure (that is, generally less than one atmosphere, depending on elevation above sea level). Fluidly connected to the storage tank  1  through a flexible hose  9  and associated piping  13  (in certain embodiments) is a wand  10  with an end piece  11 . In one embodiment, the wand  10  is simply a contoured pipe that provides the user interface and the end piece  11  a screen that acts as a filter. The end piece  11  is not required in every embodiment described and disclosed herein. 
         [0007]    During operation, the user first engages the vacuum pump  2  (which may be configured to exhaust either indoors or outdoors) to reduce the pressure within the storage tank  1 . Next, the user places the end piece  11  or the open end of the wand  10  into the liquid that is to be evacuated from the liquid container. The reduced pressure within the storage tank  1  acts as a motive force to urge the liquid into the storage tank  1  due to the pressure gradient. In the embodiments pictured herein, the liquid is used oil  15  and the liquid container is a food fryer  14 , but the scope of the present invention is not limited by the specific type of liquid or liquid container for which the apparatus is configured. 
         [0008]    When the user has evacuated the desired amount of liquid from the liquid container, the user may then allow air to pass through the system for a certain amount of time to ensure that all liquid is removed from the wand  10 , hose  9 , and piping  13 . The user is then able to disconnect the hose  9  from the piping  13  at the connector  12  without any spillage of liquid. 
         [0009]    Because the liquid vacuum apparatus uses negative pressure as the motive force (through the use of the vacuum pump  2 ) rather than positive pressure (such as a centrifugal, positive displacement, or similar pump), the possibility of spilling liquid during evacuation of the liquid from a liquid container is greatly reduced. If a leak develops in the system, liquid will not be forced from the leaking area as it would in a positive pressure system; rather, the vacuum pump  2  will pull air through the leaking area, and the liquid will not leak externally. This makes the liquid vacuum apparatus much safer to use, and it facilitates evacuation of used oil  15  at nearly any temperature, depending on the material characteristics of the hose  9 , wand  10 , piping  13 , connector  12 , end piece  11 , vacuum pump  2 , and storage tank  1 . 
         [0010]    Though the embodiments shown in the figures included herein are directed towards applications involving evacuating used oil  15  from food fryers  14 , other embodiments are described and disclosed in the specification, and the specific application to used oil  15  from food fryers  14  does not limit the scope of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0011]      FIG. 1  provides a schematic view of the storage tank and vacuum pump portions of the system. 
           [0012]      FIG. 2  provides a schematic view of the storage tank and vacuum pump with the wand and hose connected to the storage tank. 
           [0013]      FIG. 3  provides a side view of the wand submerged in a liquid container from which the liquid is being evacuated. 
           [0014]      FIG. 4  provides a schematic view of the storage tank during transfer of the contents in the storage tank to a transport vehicle. 
           [0015]      FIG. 5  provides a schematic view of one embodiment of the liquid vacuum apparatus. 
           [0016]      FIG. 6  shows an operator using the liquid vacuum apparatus to evacuate used oil from a food fryer. 
           [0017]      FIG. 7  provides another view of an operator using the liquid vacuum apparatus to evacuate used oil from a food fryer. 
           [0018]      FIG. 8  provides a side view of the storage tank. 
           [0019]      FIG. 9  provides another side view of the storage tank and the associated piping. 
           [0020]      FIG. 10  shows the storage tank not fluidly connected to any piping. 
           [0021]      FIG. 11  provides a side view of the wand and end piece. 
       
    
    
     DETAILED DESCRIPTION—LISTING OF ELEMENTS 
       [0022]      
         [0000]    
       
         
               
               
               
             
               
               
               
             
           
               
                   
                   
               
               
                   
                 ELEMENT DESCRIPTION 
                 ELEMENT # 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Storage Tank 
                 1 
               
               
                   
                 Vacuum Pump 
                 2 
               
               
                   
                 Dip Tube 
                 3 
               
               
                   
                 Vent 
                 4 
               
               
                   
                 Load Out Nozzle 
                 5 
               
               
                   
                 Tank Inlet 
                 6 
               
               
                   
                 Pump Inlet 
                 7 
               
               
                   
                 Pump Outlet 
                 8 
               
               
                   
                 Hose 
                 9 
               
               
                   
                 Wand 
                 10 
               
               
                   
                 End Piece 
                 11 
               
               
                   
                 Connector 
                 12 
               
               
                   
                 Piping 
                 13 
               
               
                   
                 Food Fryer 
                 14 
               
               
                   
                 Used Oil 
                 15 
               
               
                   
                 Wand First End 
                 16 
               
               
                   
                 Wand Second End 
                 17 
               
               
                   
                 Vent Hood 
                 18 
               
               
                   
                   
               
             
          
         
       
     
         [0023]    Before the various embodiments of the present invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that phraseology and terminology used herein with reference to device or element orientation (such as, for example, terms like “front”, “back”, “up”, “down”, “top”, “bottom”, and the like) are only used to simplify description of the present invention, and do not alone indicate or imply that the device or element referred to must have a particular orientation. In addition, terms such as “first”, “second”, and “third” are used herein and in the appended claims for purposes of description and are not intended to indicate or imply relative importance or significance. 
       DETAILED DESCRIPTION 
       [0024]    The inventor discloses and claims a method and apparatus for recovering liquid oil, particularly used fryer oil which is typically composed of soy oil, corn oil, peanut oil, Canola oil, olive oil or some combination therein. Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views,  FIG. 1  provides a schematic view of one embodiment of the storage tank  1  and vacuum pump  2  portion of the liquid vacuum apparatus. The vacuum pump  2  may be directly mounted on the storage tank  1 , as in the embodiment shown in  FIGS. 8-10 , or the vacuum pump  2  may be fluidly connected to the storage tank  1  via fluid conduit, such as piping  13 . In any case, the vacuum pump  2  is configured so that when it is engaged, the inlet of the vacuum pump  2  evacuates contents from the headspace of the storage tank  1  so that the pressure within the storage tank  1  is less than atmospheric pressure (i.e., generally at least less than one atmosphere, depending on the elevation above sea level). In the embodiments shown herein, the contents of the headspace of the storage tank  1  are generally gas and/or vapors. The pump outlet  8  may be fluidly connected to exhaust to any number of different locations or different devices. For example, it may be connected to a filter to remove undesirable components or scents, fluidly connected to vent to an area located a predetermined distance from the storage tank  1  (including somewhere outdoors if the storage tank  1  is located indoors), or simply left to exhaust next to the vacuum pump  2 . The vacuum pump  2  as shown is one means of evacuating the vapor from the storage tank  1 , as recited in the claims. The storage tank  1  shown in  FIGS. 8-10  is insulated so that used oil  15  may be stored in the storage tank  1  for a longer period of time without the oil losing an extensive amount of thermal energy, which increases the viscosity of the used oil  15  and makes it more difficult to transfer. The storage tank  1  is also constructed to such specifications as the particular application dictates. For example, the storage tank  1  will be built to withstand at least the level of vacuum the vacuum pump  2  is capable of generating. The storage tank  1  as shown is one means of storing the liquid to be recovered, as recited in the claims. 
         [0025]    In an embodiment not shown herein, valves may be placed on the pump inlet  7 , pump outlet  8 , vent  4 , load-out nozzle  5 , tank inlet  6 , and other places within the system as the specific application and necessity or convenience dictate. Accordingly, the scope of the present invention is not limited by the specific piping  13  or other fluid conduit used or the valves associated therewith, and variations and modifications from the embodiments disclosed and described herein will occur without departure from the spirit and scope of the present invention. 
         [0026]    The used oil  14  is brought into the storage tank  1  via the hose  9 , wand  10 , end piece  11 , and in many embodiments a certain amount of piping  13 . The hose  9 , wand  10 , end piece  11 , and piping  13  (if present for that embodiment) are all in fluid communication with one another. That is, during operation, fluid may flow through the end piece  11 , into the wand  10 , and from the wand  10  through the hose  9  and any associated piping  13  to the storage tank  1 . The end piece  11  is secured to the wand first end  16  and the hose  9  is secured to the wand second end  17 . The hose  9 , wand  10 , end piece  11 , and piping  13  may be constructed of any materials suitable for the application to which the liquid vacuum apparatus is put. For example, if the apparatus is to be used in handling hot (preferably ranging in temperature from 300 to 500 degrees Fahrenheit) used oil  15  from a food fryer  14 , the wand  10 , end piece  11 , and piping  13  may be constructed of stainless steel, carbon steel, high-grade rubber, Teflon or other polymer insoluble to the used oil  15  and capable of withstanding high temperatures (up to 550 degrees Fahrenheit), or any other material suitable for the specific application that is known to those skilled in the art. The hose  9  may be constructed of materials similar to those indicated for the elements above, but in most applications it will be desirable for the hose  9  to be flexible. Therefore, if a metallic substance is used to construct the hose  9 , it will likely be a braided-style hose  9 . The material for the hose  9  should be chosen so that the hose  9  possesses similar chemical, heat, and corrosion resistance as other elements in the system. 
         [0027]    If piping  13  is included in the system, the hose  9  may be connected to the piping  13  through a connector  12 . The connector  12  may be any connector  12  known to those skilled in the art capable of operation under the conditions for any specific application, including but not limited to threaded pipe fittings, cam-lock fittings, and the like. In most embodiments, the materials used to construct the connector  12  should have similar material characteristics (i.e., temperature tolerance, corrosion resistance, etc.) to those used for the hose  9 , wand  10 , end piece  11 , and piping  13 . The hose  9  as shown is one means of fluidly communicating the liquid to be recovered to the storage tank  1  or storage means, as recited in the claims. 
         [0028]    In the embodiments shown in  FIGS. 6 ,  7 ,  11  the end piece  11  is fashioned as a perforated cap that is affixed to the wand first end  16 . In this embodiment, the end piece  11  serves as a rough filter for the used oil  15  and prevents solids that are larger than the perforations within the surface of the end piece  11  from entering the wand  10  and subsequently moving through the other elements of the system. Depending on the application, the end piece  11  may not be needed for a particular embodiment, and therefore, the presence or absence of the end piece in no way limits the scope of the present invention. 
         [0029]    Once the vacuum pump  2  is started, the user grasps the wand  10  (which may be insulated if the user desires to evacuate used oil  15  when it is at an elevated temperature), which is best shown in  FIGS. 6 and 7 , and inserts the end piece  11  into the used oil  15 , which is shown schematically in  FIG. 3 . The pressure gradient between the used oil  15  and the interior of the storage tank  1  caused by the vacuum pump  2  draws used oil  15  from the food fryer  14  through the end piece  11 , wand  10 , hose  9 , and connector  12  and piping  13  (if used in that particular embodiment) into the storage tank  1 . Because the highest pressure value on the pressure gradient created by the vacuum pump  2  is at the used oil  15  level in the food fryer  14 , and the pressure at that location is approximately equal to atmospheric pressure, leaks within the system will not cause used oil  15  to spill when the vacuum pump  2  is engaged. That is, a leak in the wand  10 , hose  9 , connector  12  or piping  13  (if used) will not cause used oil  15  to leak externally as it would if positive pressure was used to produce the motive force for the liquid. Instead, if a leak develops in any component of the system, when the vacuum pump  2  is engaged, air will be drawn through the leaking component rather than used oil  15  leaking externally from the system. The wand  10  and end piece  11  form one combination of intake means as recited in the claims. 
         [0030]    Another advantage to using a pressure gradient on which the highest value is atmospheric pressure is that the hose  9 , wand  10 , end piece  11 , and piping  13  may be evacuated of nearly all residual liquid by allowing the vacuum pump  2  to pull air through those elements. Therefore, if a connector  12  and piping  13  are used, when the user disconnects the hose  9  from the piping  13  at the connector  12 , the user is assured that only a negligible amount of liquid will be present in the system. The user may allow the vacuum pump  2  to pull enough air through the system so that when the hose  9  is disconnected from the piping  13  at the connector  12 , no liquid drips from the hose  9  or the piping  13 . 
         [0031]    When the storage tank  1  becomes full of liquid, it may easily be emptied. The storage tank  1  is fashioned with a dip tube  3  at the top and of the storage tank  1  extending to between 0.125 and 18 inches from the bottom of the storage tank  1 . A load-out nozzle  5  is connected to the top-most portion of the dip tube  3  and provides an interface for evacuating the contents of the storage tank  1 . The storage tank  1  is also fashioned with a vent  4  to the atmosphere on the top end of the storage tank  1 . In the embodiment shown in  FIG. 4 , when the storage tank  1  needs to be emptied, the vent  4  on the storage tank  1  is opened and a transport vehicle with a tank and a means for creating a reduced-pressure atmosphere within the tank is fluidly connected to the load-out nozzle  5 . The reduced pressure within the tank of the transport vehicle draws the used oil  15  from the storage tank  1  through the dip tube  3  and into the tank on the transport vehicle. As used oil  15  is evacuated from the storage tank  1  into the tank of the transport vehicle, air from the ambient atmosphere around the storage tank  1  migrates into the storage tank  1  through the vent  4 . That is, during emptying of the storage tank  1 , ambient air is transferred into the storage tank  1  through the vent  4  at the same volumetric flow rate that liquid in the storage tank  1  moves out of the storage tank  1 . Therefore, during emptying of the storage tank  1 , the atmosphere within the storage tank  1  remains at ambient pressure. This is one method of emptying liquid from the storage tank  1 , and modifications and variations to this method will become apparent to those skilled in the art without departing from the spirit and scope of the present invention. For example, the storage tank  1  could be placed in an elevated position relative to a transport vehicle so that gravity would be the motive force causing the liquid in the storage tank  1  to migrate into the tank of the transport vehicle. 
         [0032]    It should be noted that the present invention is not limited to the specific embodiments pictured and described herein, but is intended to apply to all similar apparatuses for evacuating liquids from a liquid container using reduced pressure. Modifications and alterations from the described embodiments will occur to those skilled in the art without departure from the spirit and scope of the present invention.