Abstract:
Provided herein is a shallow-liquid strainer apparatus with an intake assembly that can be adjusted to keep the inlet opening completely submerged beneath the surface of the liquid to avoid letting the surrounding atmosphere into the device where it can cause inefficient flow. The intake assembly can comprise a sliding door on tracks designed to cover all or a portion of the inlet. The apparatus can be connected to a pump. The wall of the device on which the inlet is located and the inlet itself can be angled toward the back wall to facilitate submerging of the inlet. The device can comprise a strainer attached to the inlet for removing undesirable elements from the liquid. A ramp can be provided near the inlet to allow the liquid to flow upward toward the outlet. Methods of making the device are also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/635,715 filed Apr. 19, 2012, incorporated herein by reference to the extent not inconsistent herewith. 
     
    
     BACKGROUND 
       [0002]    The following patent publications may be relevant to the state of the art: JP08006482, 1996 Feb. 28, discloses an adjustable suction strainer for use in shallow water. U.S. Pat. No. 6,508,933B2, 2003 Jan. 21, discloses a self-cleaning shallow water strainer. W02011137425, 2011 Nov. 3, discloses a liquid filtering and transfer apparatus. U.S. Pat. No. 3,495,714, 1970 Feb. 17, discloses a strainer that has a swivel adapter means which permits receiving of water from any position while still permitting the strainer to remain in a level position. WO1998023545 1998 Jun. 4 discloses a water filter apparatus comprising a deflector that separates a flow of water entering a housing through an inlet into a first portion and a second portion, and directs the first portion to a water purification material. 
         [0003]    All references disclosed herein are incorporated by reference (to the extent not inconsistent with the disclosure hereof) for purposes of enablement and written description. 
       SUMMARY 
       [0004]    An apparatus and method are provided for draining or pumping water, or other liquids, from locations such as oil and gas well sites and storage tanks, basements, backyards, loading docks, parking lots, flooded roads, sports fields, construction sites, mines, animal farms, landfills, scrap yards, backyards flooded with water, or other locations. These areas are traditionally difficult to clear, and therefore in embodiments, the apparatus comprises a strainer element. Without a strainer, contaminants such as but not limited to dirt, solid particles, debris, silt, and gas and oil by-products and other undesired chemicals can damage the pump or contaminate the outflow. The apparatus can also be used for erosion control. In such an application, the liquid can be pumped out of the housing of the apparatus away from the area to be drained and to a suitable disposal site such as but not limited to a storm water drainage system, a creek, a river, a green area or some combination thereof. 
         [0005]    Many pumping devices, including those equipped with strainers do not work well in shallow liquids because once the liquid level falls below the top of the strainer inlet, the interior of the strainer housing is opened to the atmosphere, reducing suction of liquid and leading to the risk of cavitation. “Shallow liquid” is defined herein as liquid having a level below the top of the strainer inlet such that the strainer inlet is open to the atmosphere, and it will be appreciated that “shallow liquid” is relative to the height of the strainer apparatus, which can be built to any size or scale. The present disclosure solves the problems of shallow liquid transfer by providing a liquid intake adjustment mechanism which allows the liquid inlet to be adjustably closed and opened so that the portion of the inlet aperture exposed to the atmosphere can be closed and the portion of the inlet aperture below the liquid level can remain open. By designing the liquid intake adjustment mechanism so that the inlet is exposed only to liquid, but not to the atmosphere above the liquid, smooth operation of the apparatus in pumping and filtering water is achieved without bubbles and excess turbulence that would interfere with operation of a pump or other suction device connected to the apparatus. 
         [0006]    A further problem is keeping the apparatus positionally stable on uneven surfaces and in turbulent liquid, which is solved herein by providing the apparatus with a base plate, adjustable stabilizing arms and or telescoping armature, or any other stabilizing means known in the art. 
         [0007]    Provided herein is a liquid interface pumping apparatus comprising a housing; a liquid inlet aperture in said housing; a liquid outlet in said housing; and a liquid intake adjustment assembly movably attached to said housing and sized and shaped to be positioned so as to completely or substantially completely cover the liquid inlet aperture; and to be positionable to uncover any portion of the inlet aperture. “Substantially completely” covering the inlet aperture means closing it off down to all but the minimum possible pumpable liquid level. For example, if the apparatus is only capable of effectively pumping liquid having a depth of one inch, then the cover should be capable of being closed to cover the entire aperture except the portion of the aperture that lies below the water level when the water has a depth of one inch. 
         [0008]    The apparatus can also comprise a liquid intake adjustment assembly such as a sliding door assembly comprising a set of parallel tracks; and a sliding door slidably engaged with the tracks. 
         [0009]    In embodiments, the liquid inlet aperture is equipped with a strainer element sized to completely cover the liquid inlet aperture, the strainer element being fixedly or detachably attached to the housing. The strainer element can be a perforated plate or a diaphragm filter, or other filtering element known to the art. The apparatus can also comprise a base plate. 
         [0010]    In an embodiment, the housing comprises side walls attached to a bottom wall and a top wall, and a back wall and an inlet wall attached to these walls, wherein the inlet wall comprises the inlet aperture. The inlet wall is positioned at an angle between about 5 and 90° with the bottom wall, and the top wall is shortened to accommodate the incline of the inlet wall so as to enclose an interior space within the housing. 
         [0011]    The apparatus can also comprise a flow ramp disposed within the housing and angled upwardly from a point on said bottom wall proximal to the inlet wall toward the back wall, wherein the top of the ramp abuts the back wall at or above the level of the outlet. The term “proximal to the inlet wall” as used herein means closer to the inlet wall than to the back wall. 
         [0012]    The apparatus can also comprise a pump or other suction device connected to a connector on the back wall. 
         [0013]    In an embodiment, the apparatus is a liquid strainer comprising housing; a liquid inlet aperture in said housing; a liquid outlet in said housing; a liquid intake adjustment assembly movably attached to said housing and sized and shaped to be positioned so as to completely or substantially completely cover the liquid inlet aperture; and to be positionable to uncover any portion of the inlet aperture; and a filter element attached to the housing and capable of completely covering the inlet aperture. To “substantially completely cover” the inlet as specified herein means that the inlet is covered so as not to allow a pumpable amount of water to enter the housing, but is not necessarily completely water-tight. 
         [0014]    The strainer apparatus can be positioned in the path of a flowing liquid, such as a stream of falling water or a substantially horizontally flowing stream, oriented such that the liquid flows into the inlet aperture and through the strainer element, with strained liquid exiting through the outlet aperture. 
         [0015]    The apparatuses hereof are useful for pumping and/or straining any kind of liquid including water and liquid hydrocarbons, or mixtures thereof, and liquids that comprise suspended particles. 
         [0016]    Also provided herein are methods of pumping a liquid from a first location to a second location comprising connecting the apparatuses described above with a pump; immersing the apparatuses so that at least a portion of the inlet apertures of the apparatuses is beneath the liquid level; and activating the pump. 
         [0017]    In embodiments, the apparatus can be part of a method for straining suspended objects from a liquid, in which the method also comprises equipping the inlet aperture of the apparatus with a strainer element that covers the aperture. 
         [0018]    A method of making a pumping apparatus is also provided herein comprising providing a housing; forming a liquid inlet aperture in the housing; forming a liquid outlet in the housing; and second, movably attaching a liquid intake adjustment assembly the housing, wherein said intake adjustment assembly is sized and shaped to be positioned so as to completely or substantially completely cover the liquid inlet aperture; and to be positionable to expose any portion of the inlet aperture. The method can also comprise attaching a pump to the liquid outlet via a coupling attached to or part of the outlet and adapted to connect with the pump. 
         [0019]    In embodiments, the liquid intake adjustment assembly can be a sliding door assembly, and the method can comprise providing a sliding door sized and shaped to at least substantially completely cover the inlet aperture; and attaching a set of parallel tracks to the housing flanking the inlet aperture, the tracks being sized and shaped to engage the sliding door so that the sliding door is slidable therein, such that the sliding door can be adjusted to cover all or any portion of the inlet aperture. 
         [0020]    In embodiments, a strainer element can be fixedly or removably attached to the housing wherein the strainer element is sized and shaped to completely cover the liquid inlet aperture, said strainer element being fixedly or removably attached to the housing. In embodiments modular strainer elements designed to cover different sized open sections of the inlet can be removably attached to the housing. 
         [0021]    An embodiment hereof is a liquid strainer apparatus comprising a housing, an inlet aperture in said housing equipped with a perforated plate, an outlet aperture equipped with a coupling for connecting to a pump, a flow ramp positioned between the inlet and outlet apertures, and an adjustable sliding door capable of covering all or substantially all, or any part of the inlet aperture, and tracks flanking the inlet aperture on which the sliding door is slidably movable, such that it can be slid to a position that closes off any portion of the inlet aperture that is open to the air, and allows only liquid to flow into the apparatus. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  is a back view of an embodiment of the strainer apparatus, illustrating the liquid outlet and details of construction. 
           [0023]      FIG. 2  is a cross-sectional view of the strainer apparatus along Line B-B of  FIG. 1  showing the flow ramp and sliding door assembly. 
           [0024]      FIG. 3A  is a cross-sectional view taken along line A-A of  FIG. 2 , and illustrates detail of part of the sliding door of a liquid intake adjustment mechanism;  FIG. 3B  is an extended view of the embodiment shown in  FIG. 3A  showing a complete cross-section of the sliding door assembly comprising the sliding door slidably engaged with tracks on both sides. 
           [0025]      FIG. 4  is a top view of the sliding door assembly in partially open position. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    The following description of various specific embodiments is exemplary in nature and is in no way intended to limit the scope of the claims hereof. In embodiments, art-known equivalents of exemplified components, materials and method steps can be substituted for those specifically described herein and these embodiments are considered to fall within the scope of the claims. Embodiments including less than all the components, materials and method steps of embodiments specifically described herein are also considered to be encompassed within this disclosure. 
         [0027]    As shown in  FIG. 1 , which is a back view of an embodiment of an adjustable suction strainer apparatus  10  hereof, the strainer apparatus comprises a walled housing  12  enclosing an interior space  14 , the housing including first side wall  48  and second side wall  49 , inlet wall  42  (not shown, see  FIG. 2 ), back wall  40 , top wall  46 , and bottom wall  44 . In an embodiment, best seen in  FIG. 2 , inlet wall  42  is angled upwardly from bottom wall  44  to top wall  46 . In other embodiments, inlet wall  42  is angled up to join the top of back wall  40 , and there is no top wall  46 . The walls of the housing can have any width, but should be wide enough to withstand impact from a flow of liquid containing solid particles or with suspended impurities, and strong enough to withstand suction forces from within the interior space. The walls can be welded together, soldered, glued or epoxied, or fixed together by any other means known in the art, or can be fabricated as an integrated whole, such as by molding and/or machining. 
         [0028]    In some embodiments, the strainer apparatus  10  is provided with means for keeping it stable on uneven surfaces and or in turbulent liquids. These means can include a base plate  60  with or without attachment holes  62  for anchoring attachments, adjustable stabilizing arms and or telescoping armature or any other means known in the art. Base plate  60  can be welded, e.g., using stitch weld  64 , screwed, e.g., utilizing attachment holes  62 , or otherwise attached to the side walls of housing  12 . In embodiments, base plate  60  is integral with or replaces bottom wall  44 . 
         [0029]    Back wall  40  comprises an outlet aperture  18  for strained liquid exiting the strainer apparatus, connected to a tube, pipe, hose or spout (not shown) for receiving liquid from outlet aperture  18 . The connector  84  between outlet aperture  18  and the pipe, hose, or spout (best seen in  FIG. 2 ) comprises an outlet flange  70  comprising a raised circular coupling  74  comprising tapered threads  72  designed to connect with the tube, pipe, hose, or spout. In the embodiment shown, connector  84  is a three inch NPT (National Pipe Thread Tapered Thread) right-handed PVC flanged, thread-type coupling. 
         [0030]    In an embodiment, the strainer housing  12  is constructed out of metal panels that are spot and stitch welded together and attached to base plate  60 . Base plate  60  can be longer and or wider than a pump housing (not shown) that houses a pump connected to outlet aperture  18  of strainer housing  12  via circular fitting  74 . In this embodiment, base plate  60  can be provided with attachment holes  62 , such as 9/32″ holes in its corners for anchoring strainer housing  12 . 
         [0031]    The apparatus also comprises a flow ramp  20  having a width coextensive with the width of back wall  40  and extending in a downward taper to meet bottom wall  44 , in embodiments flow ramp  20  meets bottom wall  44  at its junction with inlet wall  42  (best seen in  FIG. 2 ). In embodiments, the angle of flow ramp  20  is about  10  although as will be appreciated by those of ordinary skill in the art, the ramp can be designed with other angles of incline consistent with efficient liquid flow. In embodiments, flow ramp  20  is spot welded to side walls  48  and  49 , typically at four places. 
         [0032]      FIG. 2  is a cross-sectional view of the strainer apparatus along Line B-B of  FIG. 1  showing flow ramp  20  and a sliding door assembly affixed to inlet wall  42 . The sliding door assembly comprises sliding door  22  shown in full open position, in tracks  52  affixed to inlet wall  42 . Sliding door  22  is slidably engaged with tracks  52  which are placed on inlet wall  42  parallel to each other, each engaging with opposite sides of sliding door  22 . Tracks  52  can be crimped tracks and can be spot welded or otherwise fixedly attached to the strainer housing. 
         [0033]      FIGS. 3A and 3B  show enlarged views of the sliding door assembly along line A-A of  FIG. 2 , looking upward at the bottom of sliding door  22 .  FIG. 3A  is a cross-sectional view taken along line A-A of  FIG. 2  showing detail of a sliding door embodiment of the liquid intake adjustment mechanism. Sliding door  22  is slidably engaged with crimped tracks  52 , which are spot welded to inlet wall  42  (see  FIG. 1 ) near first side wall  48 . Sliding door  22  is shaped and sized to completely or substantially completely cover strainer element  50  and strainer inlet aperture  16  and to be slidably raised and lowered on tracks  52  to cover any part of strainer element  50  and strainer aperture  16  that are or become exposed to air, i.e., are not submersed beneath the liquid being strained. Strainer element  50 , shown in the form of a perforated plate, is held in place by bracket  76 , which is also spot welded to inlet wall  42 . 
         [0034]      FIG. 3B  is an extended view of the embodiment shown in  FIG. 3A  showing a complete cross-section of the sliding door assembly comprising sliding door  22  slidably engaged with tracks  52  on both sides. Strainer element  50  is also shown beneath strainer aperture  16  held in place by brackets  76 . 
         [0035]      FIG. 4  is a top view of the sliding door assembly in partial open position, showing sliding door  22  having been slid downward in tracks  52  such that it covers the part of strainer element  50  and inlet aperture  16  that are above the liquid level (element  78  shown in  FIG. 2 ), and would otherwise be exposed to air. Inlet aperture  16  is fitted with strainer element  50 . Strainer element  50  is depicted as a perforated plate comprising perforations  51 , and is co-extensive with inlet aperture  16  and held in place by brackets  76  (best seen in  FIGS. 3  A and B) attached to inlet wall  42 . Tracks  52  are mounted on inlet wall  42 . Inlet wall  42  is attached to first side wall  48  and second side wall  49  as well top wall  46 . Top wall  46  is attached to back wall  40 , which is equipped with outlet connector  84  comprising outlet aperture  18  in raised circular coupling  74 . 
         [0036]    In embodiments strainer element  50  is designed to be easily interchanged with other strainer elements having different filtering capabilities for ease of use in straining impurities of different sizes. Strainer element  50  can be provided in many different embodiments depending on the size and nature of the impurities and the unstrained liquid. Strainer element  50  can be a perforated plate, made of metal, plastic or other suitable material. The perforations  51  can be uniform in size, shape and spacing, or can be of any size, shape and spacing which enhances liquid intake and or straining capacity, for example, in some embodiments the perforations can be larger nearer the top of the apparatus and smaller nearer the bottom of the apparatus depending on the size of the impurities and their level of suspension in the liquid. In embodiments, the strainer element  50  is a perforated, rectangular plate with equally spaced round perforations  51  about a quarter of an inch in diameter, configured along a substantially planar surface, and is capable of being interchanged for a different strainer plate. In other embodiments, strainer inlet aperture  16  can comprise a strainer element that is a diaphragm filter capable of straining out impurities based on size or chemical composition, or can comprise any other filter element known to the art. As used herein, a “diaphragm filter” is a porous plate or membrane separating two liquids, as in a galvanic cell, or a semipermeable membrane. One of ordinary skill in the art is able to select an appropriate strainer element for use depending on the size and nature of the impurities and the liquid being strained. 
         [0037]    Strainer element  50  can be integral to inlet wall  42 , or can be interchangeably attached thereto, via brackets, tracks, or other means known to the art. Strainer inlet aperture  16  as shown in  FIG. 2  is planar and extends along inlet wall  42  following the incline of the inlet wall. In other embodiments, inlet wall  42  can be stepped, and strainer inlet aperture  16  can take up part or the entire vertical or horizontal surface of the lowest step and can be at about a 90° to 180° angle to bottom wall  44 . 
         [0038]    Other conformations of inlet wall  42  and strainer inlet aperture  16  are possible including those having the inlet wall tilted at about a 45° angle with bottom wall  44 , or at any angle equal to or greater than about 5° and up to about 90°. Too acute an angle, less than approximately 5°, generally impedes the free flow of liquid. In such embodiments, top wall  46  is enlarged or made smaller so that its edge still meets the top edge of inlet wall  42 . 
         [0039]    In embodiments, the strainer apparatus  10  and its parts such as inlet aperture  16  and strainer element  50  can be configured along three-dimensional surfaces of any shape including, but not limited to wavy, stepped, concave, convex, and various combinations thereof, the particular shape and configuration depending on the nature of the impurities, the liquid to be strained, and features of the environment surrounding the strainer apparatus. For example, the strainer apparatus can be used to pump liquid from a well or narrow tube, from uneven cracks in a rock formation, from a muddy or pebbly surface, or other environments. 
         [0040]    Strainer element  50  is sized and shaped so as to cover all or any part of strainer inlet aperture  16  that in use is exposed to air or water. The sliding door  22  is part of a liquid intake adjustment mechanism comprising sliding door  22  and tracks  52 . This mechanism is designed for adjusting the area of strainer element  50  that is exposed to unstrained liquid while ensuring strainer inlet aperture  16  remains closed to the atmosphere. 
         [0041]    In embodiments sliding door  22  can move on tracks  52  from a completely open position in which the entire surface of strainer element  50  is exposed to a liquid to be strained to a completely or substantially completely closed position in which sliding door  22  does not allow any appreciable amount of liquid (i.e., any amount of liquid that would interfere with functioning of the apparatus, to enter interior space  14  of the apparatus. Sliding door  22  can be adjusted from its position entirely or substantially entirely covering strainer inlet aperture  16  to cover only part of inlet aperture  16 , and sliding door  22  and/or aperture  16  can comprise one or more positive stops, such as door stop  80  shown attached to sliding door  20  by means of an optional cable  88  ( FIG. 2 ), or other positive stop(s) known to the art. The positive stop  80  holds sliding door  22  in partially open position(s) so that any part of inlet aperture  16  which is above the liquid level and open to the atmosphere is covered, and air cannot enter the interior space  14  of the apparatus. Thus the effective open portion of strainer inlet aperture  16  open to unstrained liquid always remains below the top level of the liquid and closed to the atmosphere. 
         [0042]    In other embodiments, the sliding door assembly can be replaced by another liquid intake adjustment mechanism of any shape and material which is capable of moving up and or down over the strainer inlet aperture while effectively adjusting the area and position of strainer inlet aperture exposed to unstrained liquid. Examples include, but are not limited to liquid intake adjustment mechanisms which slide, roll, fold, expand and or contract hydraulically or pneumatically, or any combinations thereof, or any other means known in the art which allow effective adjustment of the area and position of the strainer inlet aperture exposed to unstrained liquid. The liquid intake adjustment mechanism can be adjusted manually, or can be operated by automated devices that are capable of measuring the liquid level, including but not limited to, one or more floats or other mechanical devices or various electronic apparatuses designed to measure liquid levels and send a signal to a servomotor operating the liquid adjustment mechanism. 
         [0043]    In use the strainer apparatus  10  is hooked up to a pump and intake conduit for the pump (not shown) by means of outlet connector  84 . Strainer apparatus  10  is positioned such that inlet aperture  16  is fully or partially submersed in the liquid to be strained. Sliding door  22  is adjusted so that its bottom edge is at or below the liquid level  78  so that the surrounding atmosphere is blocked from entering inlet aperture  16  and interfering with pump efficiency. As the liquid enters inlet aperture  16 , strainer element  50  filters the liquid as it flows through perforations  51 , leaving any objects in the liquid that are larger than perforations  51  outside the apparatus. The filtered liquid exits the apparatus through outlet aperture  18 , from whence it may be further conducted for reuse, further processing, or disposal. If liquid level  78  becomes lower during pumping, sliding door  22  can be adjusted downward so that its bottom edge (defining the size of the inlet) remains at or below water level. If liquid level  78  becomes higher during pumping, sliding door  22  can be adjusted upward to allow maximum liquid to move through the device and be filtered. 
         [0044]    The foregoing description is based on an orientation of strainer apparatus  10  as depicted in the figures, in which base plate  60  is parallel to the ground and orthogonal to the force of gravity. The apparatus may also be used in different positions, including upside-down positions such that the force of gravity assists in clearing debris from strainer element  50 . In such altered positions, the placement and direction of travel of sliding door  22  can be altered as necessary to accommodate the conditions of use such that the sliding door can move upward or downward relative to the liquid level. 
         [0045]    It will be appreciated that many embodiments of the strainer apparatus hereof are possible by substituting equivalent components that perform the same functions for the components illustrated herein.