Abstract:
A self priming pump attachment for transfer of liquids, such as water, attached to a rotating driving source. The rotating driving source can be a string trimmer, a drill or similar apparatus for creating a “wand” with the pump attachment on the end for placement into the liquid. The invention is affixed to the rotating driving source which drives an impeller. A drive shaft can also be used. The impeller has a plurality of veins at a optimal pitch which depends on the speed of the driving source, the density of the liquid and the distance of the discharge point from the pump housing. The pump housing encloses the impeller and contains apertures on a lower portion for drawing in the liquid, and an exit aperture on a top portion for discharging the liquid. Tubing can be affixed to the exit aperture for discharging the liquid at a desired location.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on U.S. Provisional Application Ser. No. 60/166,862 entitled “Baling (sic) Pump, Hand Held, Gasoline Engine Powered For Removal of Nuisance Water From Work Areas” filed on Nov. 22, 1999, the teachings of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention (Technical Field) 
     The invention relates to submersible pumps and more particularly to submersible liquid pump attachments for attaching to a rotating driving source such as a string trimmer. 
     2. Background Art 
     Traditionally, submersible pumps for removing or transferring liquids such as water or the like, are self contained units. These pumps contain the drive source in the pump housing. Therefore, the housing for the drive source must be waterproof. This increases the cost and complexity of a submersible pump. Other types of pumping mechanisms utilize centrifugal pumps with a hose or tubular attachment which is placed in the liquid for liquid transfer. U.S. Pat. No. 5,305,585 to Cousineau and U.S. Pat. No. 4,779,404 to Bell, illustrate this. These types of pumps are also expensive and bulky for use on small projects. The present invention solves these problems with a pump attachment for any type of rotating drive source such as a string trimmer. The present invention is an attachment in addition to attachments presently available for string trimmers as shown in Homelite® operators manual, P/N PS02218. A user can simply connect the pump attachment to a string trimmer, place the pump housing in the liquid to be transferred, and start the trimmer. 
     SUMMARY OF THE INVENTION (DISCLOSURE OF THE INVENTION) 
     A submersible pump for transfer or removal of a liquid as an attachment to a rotating drive source is disclosed. The most significant novelty of this particular pump in its preferred embodiment is its ability to attach to a string driven trimmer, thus making it portable and versatile for a variety of liquid transfer and/or removal operations. Though this is the preferred embodiment of this pump, it will also work with other rotary driven appliances as an after market attachment. 
     The preferred pump attachment comprises a connector to connect the drive source to an axle for driving an impeller. The impeller is housed within a pump body and draws the liquid into the pump body, through the impeller and expels the liquid out of the pump body through an outlet tube. A screen or apertures in an inflow plate can be used to filter particulates and keep them from entering the pump body. The connector can have an extension for ease of use and the extension can be curved or angled to for placement of the pump head in the liquid in difficult situations. The pump attachment can be used with other rotating drive sources such as an electric or battery powered drill. 
     Because the pump housing and its internal working parts can be directly submerged into the liquid, it requires no pre-priming. Further, because the drive mechanism is in a remote location from the liquid it eliminates the costly construction of submersible motors and engines, while at the same time allowing for the safe and effective priming and transfer of the liquid in question. 
     In the preferred embodiment the invention connects to the end of a “wand” as a fixed extension to the drive mechanism of a weed trimmer. The unit can be hand held and its position manipulated to draw the liquid from any desired position. For instance, it can draw from near the top of the liquid&#39;s surface and thus avoid slurry or silt that may collect near the bottom of certain bodies of water or containers. It may also draw liquid from near the bottom if so desired, thus allowing for greater pressure and a higher volume of output. The operator can, in a remote location from the liquid, direct the wand with its attached pump accurately in hard to reach areas or cramped spaces. 
     The pump invention has a unique impeller. The impeller allows that the pump transfers the maximum amount of water, with the greatest efficiency by causing a vortex of maelstrom effect. This is accomplished by its multiple, pitched and enclosed veins. These veins are likewise scalloped or tapered towards the center of its axis thus aiding in its cavitation and vortex effect. Thus, a smaller amount of surface is directly resisted by the liquid because of the cutting action of the reduced and pitched area of the vein. This causes the centrifugal force to take place more freely as the impeller rotates on its axis, thus producing less load on the drive mechanism while at the same time drawing an increased amount of water up and out of the pump housing with greater rpm&#39;s and increased suction. 
     The field of application for such a pump attachment is wide and varied. The fact that it connects to an existing home appliance that is common to many households makes it a practical investment to the professional and home owner alike. It can be used effectively in situations such as flooded boats, pool care, washing machine repair, stagnant water removal, flooded basements, golf course maintenance, flooded water meters, plumbing applications, dairies, farming and ranching applications, fish hatcheries and ponds, nurseries, and virtually any liquid transfer or disposal situation. 
     A primary object of the present invention is to provide an attachment to a rotating drive source such as a string trimmer for the removal or transfer of a liquid. 
     Another object of the present invention is to provide a pump that is self priming. 
     Yet another object of the present invention is to provide a submersible pump where the drive source is not submerged into the liquid to be transferred or removed. 
     A primary advantage of the present invention is that the pump attachment is less expensive than prior art submersible pumps. 
     Another advantage of the present invention is its simplicity of design. 
     Yet another advantage of the present invention is its durability. 
     Other objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated into and form a part of the specification, illustrate several embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating a preferred embodiment of the invention and are not to be construed as limiting the invention. In the drawings: 
     FIG. 1 is a perspective view of the Portable Submersible Liquid Pump Attachment attached to a gas powered string trimmer with a bend in the shaft of approximately 45°; 
     FIG. 2 is a perspective view of the invention as shown in FIG. 1, with a straight shaft; 
     FIG. 3 is a perspective view of the invention as shown in FIG. 1 with the shaft bent at an angle of approximately 90°; 
     FIG. 4 is an exploded view of the preferred pump attachment; 
     FIG. 5 is a top view of the pump housing; 
     FIG. 6 is a front view of the pump housing; 
     FIG. 7 is a side view of the pump housing; and 
     FIG. 8 is a bottom view of the pump housing. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     (BEST MODES FOR CARRYING OUT THE INVENTION) 
     FIGS. 1,  2 , and  3  show the pump invention attached to a string trimmer. Although only a gas motor trimmer  18  is shown, the pump attachment  10  can also be attached to an electric motor trimmer. As can be seen from these figures, the pump attachment  10  can be configured at different angles from the driving stem  20  of the motor trimmer  18 . 
     Referring to FIG. 4, the pump attachment consists of three major assemblies that make up its preferred embodiment, those assemblies consist of a pump housing assembly  12 , a coupling and axle assembly  14 , and the impeller  16 . 
     The pump housing is shown in FIGS. 5,  6 ,  7 , and  8 . The purpose of the pump housing  12  provides a vessel or housing through which the liquid can be drawn in, pressurized, and expelled to an outlet opening  22 . In addition, the pump housing  12  provides a means to fasten the pump housing  22  to the trimmer tubing  20  as an exterior part of the drive coupling, and provide a housing for the internal working parts which include the coupling and axle assembly along with the impeller  16 . 
     The first element of the pump housing  12  is its under surface plate  24 . This plate  24  provides an intake area for the pump cavity as well as creating its lower enclosure. It is preferably made of a thin (approx. ⅛″ thick) round (approx. 3″ diam.) flat plate with a series of small holes  26  drilled transversely, through the flat portion, FIG. 8, of the plate. This series of holes  26  preferably begins in the center and in a circular pattern and extends outwards towards the plate&#39;s perimeter finally terminating well within its diametric limit. Other hole patterns can be used with the same effect. The only limitation is that the number of holes  26  and size of the holes  26  must be of sufficient area to allow sufficient liquid to flow into the pump housing  12  at an optimally efficient rate. The liquid will be drawn through these holes  26  for the purpose of an intake, and the diameter of the holes can also serve as a strainer of particulates such as gravel or sand that may be drawn in with the liquid. A screen can be used to filter finer particulates, if desired (not shown). At the far edges of the surface plate  24 , fastening holes  28  are drilled for screws  30 , or the like to affix the plate  24  to the under surface of the pump housing  32 . 
     The next portion of pump housing  12  is pump housing body  34  as shown in FIG.  4 . It preferably consists of a cylindrical, tubular portion of the pump housing  12 . The pump housing body  34  forms a cavity through which the liquid is drawn in from the under surface plate  24 , drawn through its tubular length to the impeller  16 , and pressurized to be expelled through an outlet  22  in the top surface plate  36 . The outside tubular diameter of the pump housing body  34  is essentially the same as the outside diameter of the under surface plate  24 , so as to accommodate their being aligned and affixed to each other with three screws  30  through holes  28  and screwed into the wall of the pump housing body  34 . 
     The preferred top surface plate  36  is shown in FIGS. 4 and 5. This portion of the pump housing assembly  12  provides the upper enclosure for the pump housing cavity as well as an aperture for the expulsion  22  of the liquid out of the pump housing cavity to a remote location. It further provides a means by which to affix the pump in its entirety to the string (flexible shaft) driven trimmer. The preferred top surface plate  36  consists of a thin round plate with diametric values that are similar as the under surface plate  24 . Top surface plate  36  has a rotating axle hole  38  drilled through its flat center to accommodate the insertion of a rotating axle  44  in the coupling assembly. Also welded in the center of the top plate  36  at a 90 degree angle is a piece of round tubing  40  which is of sufficient inside diameter to house a bearing  42  for the rotating axle  44  as well as a sufficient inside diameter to sleeve the outside dimension of the tubing extension  40  which houses the drive shaft on a weed trimmer (not shown). The inside dimension of this tubing  40  is only slightly oversized in this respect so as to provide a tight fit of close tolerance. The tube  40  is then slotted  46  along its length, half the distance of its overall span. This slot  46  in conjunction with a sufficiently thin wall that will allow flex when the tubing is compressed with an outside clamp, such as a hose clamp, affords it to be securely attached to the flexible shaft tube extension that is a standard part of the weed trimmer (not shown). The top plate  36  further has an outlet aperture for expulsion of the liquid after pressurization in the pump housing cavity. An outlet tubing  22  is then affixed, preferably by welding, to the top plate  36  after having its inside diameter aligned in relationship to the aforementioned outlet aperture. A flexible hose or tubing  48  may be affixed in order to pump the pressurized liquid to a remote location, as shown in FIG.  1 . As with the bottom plate  24 , top plate  36  is affixed to the top of the pump housing body in order to enclose the pump housing cavity and provide a pressurization chamber to house the impeller  16  as it spins on its rotating axle  44 . The pump housing  12  can be hard metal, plastic, a combination of both, or other suitable materials. In addition, the physical configuration of the pump housing  12  can be changed without affecting the operation of the pump. 
     The second major portion of the pump&#39;s construction is the axle and coupling assembly  14 . The function of this portion of the pump is to couple the flexible, rotating shaft of the weed trimmer to the shaft or rotating axle  44  of the pump mechanism. Further, the purpose of this assembly is to provide a means by which to fasten the impeller  16  to the rotating shaft  44  of the pump. Referring to FIG. 4, a cylindrical axle  44  of appropriate diameter so as to fit within the dimensions of the centered hole  38  on the top plate  36  of the pump housing  12  is the means to fasten and turn impeller  16 . This axle  44  is of appropriate length as well, so as to fit within the dimensional limits of the pump housing  12 . The axle  44  is constructed so as to have an inner key way or square tube cavity  48  within its top portion that couples to the flexible shaft of a weed trimmer by means of a male, square, tang, that protrudes as a rotating shaft, which is common to weed trimmers (not shown). The inner key way  48  is slightly oversized in relation to the tang and acts as a receiver for this tang with a fit of nominal tolerance so as to provide a secure and positive coupling between the rotating pump axle  44  and the weed trimmer&#39;s flex shaft. The opposing end of the axle  44  is equipped with the appropriate amount of threads  50  so as to accommodate the fixing of the impeller  16  to the axle assembly  14  by means of a nut and washer assembly  52 . A nut that has threads to match that of the ones cut into the lower portion of the axle assembly  14 , is threaded onto the axle  44  and then an appropriate washer is slipped over this portion of the shaft  44  as well to provide a backing for the fastened impeller  16 . Next the impeller  16 , the scalloped side of its veins  62  toward and at a right angle in relationship to the shaft  44 , is slipped onto the threaded side  50  of the axle  44  by means of an impeller hole  54  of appropriate diameter in the center of the impeller  16 . Another washer of appropriate size is slipped onto the axle and then another nut is threaded onto the axle  44  and given the appropriate tightness so as to securely fasten the impeller  16  to the top plate  36  of the pump housing  12  by means of two lock rings  66  along with a bearing  42  that provides smooth rotation of the axle assembly  14 . Two square shouldered grooves  58  are cut into the axle  44  at appropriately spaced points along the shaft  44 . These grooves  58  are cut in line with the rotation of the axle  44  around its circumference to an appropriate depth and width so as to receive the snap rings  56  that will act as keepers for the axle and coupling assembly  14 . First the bottom snap ring  56  is set into the groove  58  and a thrust washer  60  with a hole of appropriate size is slipped over the axle  44 . Then a bearing  42  of sufficient inside diameter, to receive the axle assembly  14 , and appropriate outside diameter, to provide a press fit into the center tube  40  on the top plate  36  of the pump housing  12 , is press fit into the inside of the tube  40  until it is seated firmly at the bottom of the tube  40  and against the top flat portion of the top plate  36 . Then the axle assembly  14  with the lower snap ring  56  and thrust washer  60  in place is inserted upward through the center hole  38  in the top plate  36  of the pump housing  12  and the inside diameter of the bearing  42  simultaneously as they are aligned with one another. To complete the assembly a top thrust washer  60  is slipped over the axle  44  after which the top snap ring  56  is secured in its respective groove  58 . The joining of the coupling and axle assembly  14  is complete and the top plate  36  of the pump housing  12  may now be affixed to the pump housing body  34 . As shown in FIGS. 1,  2 , and  3 , a hose  49  of appropriate length is placed over the outlet tube  22  of the pump housing  12  to remove or transfer liquid to a remote location. The entire assembly  10  is attached via the coupling tube and the square tubular key way in the axle and coupling assembly  14  by inserting these over the matching end of the string drive weed trimmer, finally being secured by the appropriate type of clamp around the outside of the centralized pump housing tube (not shown). 
     The function of this pump is the unique construction of its impeller  16  as shown in FIG.  4 . The impeller  16  is the rotating part of the mechanism, which after coming in contact with the liquid, produces the maelstrom or whirlpool effect, thereby drawing the liquid up from the pump inlet at the bottom plate  24  and expelling it under pressure through its top outlet  22 . The veins or blades  62  that come into contact with the liquid are pitched at such an angle so as to cause a cutting or slicing motion through the liquid thereby using a mechanical advantage to lift the water towards the outlet  22  while at the same time decreasing load on the motor of the string trimmer. These veins  62  are likewise tapered so as to narrow as they extend inward towards the center of the axis upon which the impeller  16  spins. This in effect decreases the surface area that contacts the liquid thereby increasing rpm&#39;s, and further decreasing the load. The veins  62  have a slight curvature along their surface which further decreases friction and load. These veins  62  are enclosed by an impeller tube  64  that is molded as a single part of their outward extremity, and act as an enclosure opposite the impeller&#39;s axis. This acts to create a tunnel effect that contains the liquid more efficiently within the working area of the impeller  16 , and eliminating liquid bypass. This intensifies the swirl effect within the pump housing  12  and creates a greater amount of suction on the inlet side and higher amount of pressure on the outlet side, while trapping and moving an increased portion of liquid. The final feature of the impeller  16  is the effect of cavitation that takes place in the top center near its axis. As a result of the tapered veins  62  in conjunction with the impeller tube&#39;s  64  tunnel effect, and the lowered frictional construction of the impeller  16  in general, there is a low pressure area that is created near its center. This unique cavitation that is a result of the sum total of the impeller&#39;s novel construction creates an unusually strong draw of lower pressure liquid up from the intake side, and an unusually strong output of high pressure liquid on the output side. This creates a pump impeller  16  that can draw an unusually large volume of water, while at the same time producing only a minimal amount of load on the drive motor. This makes for an efficient, yet effective pump mechanism. 
     The invention can be modified for use with other rotating drive sources such as a hand held drill. The axle can be directly placed in the chuck of the drill for use (not shown). 
     Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art, and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above, are hereby incorporated by reference.