Abstract:
A centrifugal pump is provided for use with fluids, gases, and solids in connection with a drive shaft and a motor. The pump has a housing and at least a 30 degree sloped impeller mounted on the shaft within the housing. The housing has opposing inlet means on each side of the impeller and a discharge outlet. The impeller can be constructed as split through its center with an associated split housing or being an integral part.

Description:
RELATED APPLICATIONS 
   This is a continuation-in-part of application Ser. No. 10/672,175, filed Sep. 26, 2003 now U.S. Pat. No. 6,942,448. 

   FIELD OF THE INVENTION 
   This invention is generally directed to centrifugal pumps having rotatably driven impellers mounted within a housing so as to create a fluid flow through such housing between a pair of opposite inlets and an outlet therein. More particularly, the invention provides a centrifugal pump which includes a single or a double volute impeller that attaches to a drive shaft or a motor and is rotatably disposed within the housing. Opposing fluid inlets or suction tubes are created between two opposite sides of the housing from which uniflow fluids are directed to a fluid outlet also formed in the housing. 
   BACKGROUND OF THE INVENTION 
   U.S. Pat. No. 4,688,987 to Ericson et al discloses a centrifugal pump having a split impeller which is mounted directly to an existing drive shaft. The inner surfaces of the hub portions of the split impeller are knurled or otherwise provided with ridges as to bite or lock the hub against the drive shaft when the two portions of the impeller are clutched together. 
   This prior centrifugal pump is particularly adapted for use in the engine compartment or hull of a marine vessel wherein the impeller is attached for rotation with the drive shaft, such as a propeller drive shaft, such as a propeller drive shaft, and wherein the pump housing is mounted so as to be in a surrounding and spaced relationship to the impeller blades and drive shaft. The impeller is freely rotatable in order to pump fumes, solids, or fluids through annular intake openings in the pump housing and deliver the same through an outlet formed in the pump housing. 
   U.S. Pat. No. 5,051,071 to Haentjens discloses a split impeller centrifugal pump for mounting on an existing drive shaft. The pump has opposed annular inlets. The pump does not contain vanes but grooves and air ducts. 
   It is an object of this invention to provide a self priming centrifugal pumping apparatus which couples to a drive shaft in an environment wherein liquids, gases, or solids may be encountered and wherein the pump is structured so that the impeller is not journaled or directly mounted to the pump housing. In this manner, no heat is generated during the rotation of the impeller by friction between the impeller and the housing as is the case in a pump which the impeller is directly carried by the pump housing. 
   It is also an object of the present invention to provide a centrifugal pump apparatus which is coupled between the engine and the drive shaft to provide a pumping apparatus which does not require the lubrication and maintenance associated with conventional centrifugal pumps. 
   It is another object of the invention to provide an improved self priming pump for removing liquid from a vessel or container that is operated from nearby or remote areas. 
   SUMMARY OF THE INVENTION 
   According to the present invention there is provided a self priming centrifugal pump apparatus which pumps flowable materials, runs wet or dry, and pumps forward or in reverse. 
   The apparatus comprises a drive shaft, an engine or motor for driving said drive shaft, a housing having front and rear walls, peripheral side walls and a pair of opposing fluid inlet opening or optionally suction tubes which surround the power source and provides equal pressure from both sides to an impeller. An impeller which is sloped on at least one side and forms a coupling of the motor with the drive shaft within and in spaced relationship with the housing. The two sided slopes expedite movement of the flowable material outward to the tapered vanes. Accordingly, the impeller and housing cooperate to discharge different types of materials in response to the rotation of the drive shaft. 
   According to one embodiment of the invention, the housing comprises front and rear wall portions, a pair of opposing fluid inlet openings in said front and rear walls of said housing providing equal pressure from both sides on the impeller means. The housing is provided with two sections in which each is provided with a fluid inlet opening and a central opening for a drive shaft in at least one section of the housing to provide for a drive shaft. 
   The impeller may be adapted to be connected to a motor and a drive shaft or it can connect directly to a motor. The pump may be used by itself to carry fluid materials such as solids and fluid from a vessel or container or body of water or can be used in connection with a drive shaft of a propeller for a boat. 
   According to another embodiment of the invention, there is provided a fluid immersible self-priming discharge pump for removing a fluid such as water and sludge from a container land or vessel or body of water. The discharge pump comprises a motor, a housing associated with the motor and a sloped impeller. A drive shaft is within the housing and operatively connected for rotation by the motor. An impeller associated with the drive shaft and rotatable within the housing so as to draw fluid under equal pressure into the housing through the inlet openings in the housing and pass it along sloped surfaces so as to discharge the fluid through the outlet openings by means of impeller blades. 
   According to another embodiment of the invention, there is provided a fluid immersible self priming discharge pump for removing a flowable material or fluid such as water from a container or vessel. The discharge pump comprises a hydraulic motor, a housing associated with the motor having at least two opposite fluid inlet openings which create substantially equal pressure on opposing sloped sides of the impeller. A drive shaft is within the housing and operatively connected for rotation by the motor. An impeller means is associated with the drive shaft and rotatable within the housing so as to draw fluid under equal pressure into the housing through the inlet openings and pass it along the sloped surfaces so as to discharge the fluid through the outlet openings by means of the impeller blades. A hose or nozzle is associated with the outlet opening to carry the discharge fluid away. The means for activating the motor can be in the form of a hydraulic pump which is located at a separate area, for example, outside of the vessel or container or on another boat. Two sloped surfaces provide a faster discharge of fluid. 
   In accordance with a further embodiment the pump is provided with a split impeller and a split housing, each with connecting means so as to attach the pump to an extinguishing drive shaft without disassembling the shaft structure. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates the mounting of the pump of the invention with the propeller drive shaft and transom of an inboard motor; 
       FIG. 2  is an enlarged front plan view of the pump housing taken along lines  2 - 2  of  FIG. 1 ; 
       FIG. 3  is a side view of an integral impeller of the invention; the other side optionally being a mirror image. 
       FIG. 4  illustrates a fluid immersible pump of the invention. 
       FIG. 5  illustrates a side view of a further impeller of the invention, the other side being a mirror image. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A more complete understanding of the invention will be had by referring to the following description and claims of a preferred embodiment, taken in conjunction with the accompanying drawings, wherein like reference members refer to similar parts throughout the several views. 
   With continued references to  FIGS. 1 and 2  of the drawings, the centrifugal pump  2  according to one embodiment of the present invention, the pump is shown as it is mounted in relationship to a propeller drive shaft  16  within the hull of an inboard motorboat  10  from the propeller  20  through a transom, to the motor or engine  18 . A suitable of stuffing box  22 ,  22 ′ can be mounted so as to rotatably support the drive shaft  16  and pump  12 . The discharge outlet  23  is attached to a hose  24 . It should be noted that although the centrifugal pump  12  is being described for use with the propeller drive shaft of a conventional inboard motorboat  10 , the pump  12  could be used in other environments. In addition, although only a single pump  12  is shown in the preferred embodiment, there may be occasions when two or more pumps would be used in the same environment such as a boat having twin screws driven by a pair of parallel drive shafts. 
   As seen in  FIG. 3  the impeller  38  comprises blade members  32  about its periphery. Bolts or other fastening means  34  connect the front side of a clam-shell like impeller to the back side (not shown). However, the impeller  38  may be solid or joined at its periphery by welding so that the bolts  34  are not required. A slope of at least 30°, generally about 30 to 45 degrees on the impeller is generally suitable for moving the flowable materials to the blades  32 . 
   In  FIG. 4  there is illustrated a fluid immersible pump  60  which can be used as a bilge pump that operates from a remove area, for example, another boat which provides a source of power. Pump  60  comprises a pump housing  61  in which an impeller  67  is mounted for rotation by a drive shaft  67 . The drive shaft  68  is operatively connected to a hydraulic motor  62  that it is operated by a hydraulic pump (not shown) through hydraulic lines  65 ,  65 ′. 
   The housing  61  is provided with two or more fluid intake openings  63 ,  63 ′ and a discharge opening  71  to which there is attached at least one discharge hose or nozzle  64 . The water enters so that there is equal pressure from both sides on the impeller  67  whereby the pump is self priming. 
   Fluid openings  63 ′ are provided on one side of the impeller  67  and a fluid opening  63  is provided on the other side of the impeller  67  so as to create equal pressure and to be self priming. 
   The discharge opening  71  can be tangential as shown in  FIG. 2 , but advantageously it is horizontally aligned with the impeller  67  as seen in  FIG. 4 . Optionally, the housing  61  may have a stand such as foot  70  and  70 ′. Also, the interior of the housing  61  may contain a screen  72  to prevent intake of large objects which may damage the impeller  67 . 
   In operation, the motor  62  rotates the impeller  67  which draws a fluid, for example, water, through the inlets  63 ,  63 ′ and into pump  60  that it is carried outwardly along the sloped impeller and propelled by the impeller blades through the discharge hose  64 . The hydraulic lines  65  and  65 ′ may be connected to a hydraulic pump on a vessel which is remote from the area of operation. The inlets could also comprise a pair of tubular openings which suck the fluid into the housing. 
   As seen in  FIG. 5  there is an impeller  72  which is split along  74 . The impeller  72  is provided on each side with sloping vanes or blades  74 . Preferably the blades  74  diminish in thickness as they extend outward. The blades  74  are found on the sloped portion  76  of the impeller  72 . The impeller  72  has sides that slope and a flat portion  79  about its center which is formed as a result of grinding or shearing so as to balance the impeller. 
   The impeller  72  is provided with an opening or channel  77  which may be keyed for use on a drive shaft (not shown). The impeller may be bolted together (not shown) when placed on a drive shaft or may be welded along line  74  to make it integral. 
   The outlet of the pumps may be provided with a male pipe thread nipples (not shown) with cam-lock safety fittings so as to meet OSHA requirements. 
   In the larger sized remote pumps where there is a discharge opening of about 16 inches and an intake opening of about 10 inches, the sloped impeller is about 26 inches in diameter and is provided with impeller blades or paddles of about 5 inches in length on both sides which are integral or separate. 
   The impeller can be constructed using aluminum, and/or injected molded plastic, or glass reinforced plastic. The impeller, when removed from the mold is generally clean and does not require any machining, just the removal of the fill spout and the drilling and tapping of one hole for the threaded bolt. The finish of the impeller when removed from the mold has a high quality lustrous finish. 
   Depending on its use, the impeller may be a solid integral piece, comprised of two parts joined at its periphery in a clam-shell like fashion and hollow in the interior with a channel through its center for a drive shaft. Also, the impeller may be split into two halves for ease in installing on a drive shaft. 
   The housing is generally split in two halves so as to enclose the impeller. However, the housing can have openings on opposite sides along the drive shaft for the inlet of the material. The openings can comprise slits or connecting elements for attachment to hoses. 
   The drive shaft may optionally contain a cutting device (not shown) which cuts through packed dirt or particles so as to loosen them for passage through the impeller for discharge. This is suitable for sludge, grain and the like. 
   Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.