TECHNICAL FIELD 
       [0001]    The present invention relates to an improved centrifugal pump. 
       BACKGROUND 
       [0002]    Centrifugal pumps are the most common type of pump. A centrifugal pump has two main components, one moving and one stationary. The moving component consists of an impeller and a shaft and the stationary component consists of a housing. 
         [0003]    Dynamic pumps, whether they have a standard impeller or a disc design impeller, have a common problem. The problem is the need to have a seal between the inlet (low pressure) side and the outlet (high pressure side). Many attempts have been made to correct or “seal” this problem. The result has always been the same. When the gasket or material sealing the gap between the high and low pressure sides of the pump are worn, the fluid, or material being pumped, leaks between the two. This is primarily caused by the inability of the internal features of the pump to close the gap when the gasket wears away. 
         [0004]    Since all efforts have failed to cure this problem, manufacturers have abandoned sealing efforts and have instead designed pumps with a close tolerance to try to control the amount of “blow-by” or leakage between the inlet and outlet. Engineering their pumps in this fashion has made them inefficient. Most estimates show this efficiency to range from 8% to 20% so that the energy being spent to move fluid or material is also being wasted by 8% to 20%. Applicant&#39;s new improved pump is more efficient. 
         [0005]    In order for a dynamic pump to maintain good pressure, the tolerance between the impeller and the housing must be very close. This prevents or controls the amount of blow-by or mixture of high and low sides. Because this tolerance or gap is so close, any solids in the material being pumped can clog, foul or build up over time and cause friction between the impeller and housing. A small piece of hard material, such as granite, can lodge itself in this gap and physically stop the impeller. This sudden stop most always ends with damage to the equipment. Motor couplings and keyways are designed to reduce costly pump damage, but more often than not, permanent damage will occur to the impeller or housing. 
         [0006]    When pumping fluid with a dynamic pump, it almost always has to be primed. While in service, air pockets in the feed line will cause gas or vapor lock. Applicant&#39;s improved pump will act as a fan to pump through the air or gas and pull the fluid to the pump. This eliminates the need to prime. 
       SUMMARY OF THE INVENTION 
       [0007]    The invention is a centrifugal pump comprising a housing, having an inlet, an outlet and a volute. A motor is mounted on the housing. The motor rotatably drives a two piece impeller within the volute, for pumping fluid, or other material, through the housing from the inlet to the outlet. The pump has seals between the inlet, or low pressure, and the outlet, or high pressure, areas of the pump. As centrifugal force of the two piece impeller forces the fluid outward, it is restricted by the concave shape of the two parts of the impeller. This creates pressure and pushes the two impeller portions outward to force the two halves of the impeller apart. This creates a sealing point between each impeller part and the housing, at a flat surface of contact between the two. A Teflon washer, or other suitable material, is inserted in between the impeller and the housing to reduce wear and friction. The more pressure created between the two parts of the impeller and the housing, the better the seal is between them. 
         [0008]    The pump of this invention has a close tolerance only at the output point or perimeter of the impeller. The centrifugal force and speed of fluid or material at this point greatly reduces the chance of any debris being lodged in this area. If solid material occurs, it is easy enough to reduce seal width at the contact point between the impeller and the housing. This will increase the gap between the two sides or halves of the impeller to ensure that the solids pass through unobstructed. 
         [0009]    Maintenance on the new pump of this invention is straight forward. The use of Teflon washers and brass bushings will keep rebuilding costs down. The pump disassembles from one end, as do most existing dynamic pumps. Inspection of alignment pins and impeller veins can be done easily and all washers, bushings, seals and bearings can be replaced at once with minimal time and stock. 
         [0010]    The above advantages and various other advantages and features may be recognized by those of ordinary skill in the art based on the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is an exploded view of a dual intake pump of this invention; 
           [0012]      FIG. 2  shows a side view of a pump of this invention; 
           [0013]      FIG. 3  shows a flow diagram of the pump; 
           [0014]      FIG. 4  shows a chain or belt drive for the pump; 
           [0015]      FIG. 5  shows a gear drive for the pump; 
           [0016]      FIG. 6  is a top view of the drive side of a dual intake pump; 
           [0017]      FIG. 7  is a top view of a dual intake disc pump; 
           [0018]      FIG. 8  is a side view of an impeller disc; 
           [0019]      FIG. 9  is a side view of a cone spreader; 
           [0020]      FIG. 10  is a top view of a single intake disc pump; 
           [0021]      FIG. 11  is a front view of an impeller disc; 
           [0022]      FIG. 12  is a front view of an impeller disc assembly; 
           [0023]      FIG. 13A  is a detailed front view of an impeller disc; 
           [0024]      FIG. 13B  is a top view of the impeller halves and pins; 
           [0025]      FIG. 14A  is a front view of an impeller disc blade; 
           [0026]      FIG. 14B  is a side view of an impeller disc blade; 
           [0027]      FIG. 15  is one half of the housing and impeller of a single intake pump; 
           [0028]      FIG. 16  is the other half of the housing and impeller of a single intake pump; 
           [0029]      FIG. 17  is a side view of the inlet side housing with a weep hole; 
           [0030]      FIG. 18  shows a seal ridge and weep hole chamfer in the housing; 
           [0031]      FIG. 19  is a diagram which depicts the flow of a turbine; 
           [0032]      FIG. 20  is a side view of a turbine of this invention; and, 
           [0033]      FIG. 21  is an exploded view of a turbine of this invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
         [0035]    Referring to  FIG. 1  there is shown an exploded view of dual intake pump  10  of this invention. There are two impeller parts  12  and  14 . The housing is shown in three parts, the drive side housing  16 , the center portion housing  18  and the non-drive housing portion  20 . There are two pipe flanges  22  and  24 . There is also an output pipe flange  26 , part of housing  18 . There are shown three of a plurality of flange mounting studs  28 ,  30  and  32 . 
         [0036]    On the drive side there is an inner sealing ring  34  and a bearing  36  to hold the impeller inlet tube  43  allowing it to rotate. Seal  34  sits between housing  16  and impeller part  14  at impeller ridge  42 . Seal  40  sits between pipe flange  22  and inlet tube  43 . Seal  38  sits between inlet tube  43  and housing  16 . On the non-drive side, seal  44  seals housing  20  against impeller  12  at impeller ridge  50 . Bearing  48  holds impeller inlet tube  45 . Seal  46  seals pipe flange  24  to inlet tube  45 . Seal  46  and bearing  48  fit between housing  20  and inlet tube  45 . Bolts  52 ,  54 ,  56  and  58  are four of a plurality of bolts, which connect together the three parts of the housing  16 ,  18  and  20 . 
         [0037]    Referring to  FIG. 2 , there is shown what looks like a standard dynamic pump  60  with an inlet  62  and an outlet  64 . The major difference between the pump of this invention and standard dynamic pumps is the center shaft. Unlike a standard dynamic pump the center  62  is hollow like a pipe and is the intake. 
         [0038]      FIG. 3  is a diagram depicting the fluid passage, having a dual input  66  and  68  and output through volute  70 . The cut-away diagram shows four points of the housing  72 ,  74 ,  76  and  78 , the housing being circular. There are depicted four contact points  80 ,  82 ,  84  and  86  between the housing and the impeller, also circular. As the centrifugal force of the impeller forces the fluid outward, it forces the two halves of the impeller apart. This creates a sealing point  80 ,  82 ,  84  and  86  between the impeller and the housing, at a flat surface of contact between the two surfaces. A Teflon washer or other suitable material can be inserted in between to reduce wear and friction. The more pressure created between the two halves of the impeller, the better the seal between the impeller and the housing. 
         [0039]    Referring to  FIG. 4 , there is shown a basic dynamic pump  60  of the invention where the pump is driven by a chain drive  90 .  FIG. 5  shows the same basic dynamic pump  60  where the pump is driven by a gear drive  92 . 
         [0040]    Referring to  FIG. 6 , there is shown the drive portion of the pump of  FIG. 1 , and also shows the pump drive motor  94  with a belt drive  96 . Also shown is pipe supply line  53  with pipe supply line flange  55 . Bolts  57  and  59  are two of a plurality of bolts to connect with flange  22 , 
         [0041]    The same principles used in a dynamic pump may also be used in a disc style pump. A standard disc pump has discs that are flat. The disc pump of this invention has concave discs. Referring to  FIG. 7 , there is shown multiple concave discs  100  of impeller halves  102  and  104 . The center disc  101  is not concave. The concave shape of the discs will allow pressure between discs  100  to increase as the flow of material moves outward while the pump is in motion. This increase in pressure will ensure a tight seal between the impeller halves  102 ,  104  and the housing, not shown here, but shown in  FIG. 1 . 
         [0042]    Distribution cones or spreaders  106  and  108  help to spread the fluid or material being pumped between the discs equally. In order to maximize the flow from the pump and ensure needed pressure the discs need to be equal distances apart. Each disc will be moving the same amount of material. The length, width and shape of the distribution cones  106 ,  108  will change dependent upon the material being pumped, the amount of flow, and the size and number of the discs.  FIG. 8  shows the front of a disc  100  with multiple pins  110  and multiple ridges or bumps  112 , which also help to spread the material being pumped. The center disc  101  is not concave and has distribution cones  106 ,  108  on both sides.  FIG. 9  is a front view of spreader  106  and  108 . 
         [0043]      FIG. 10  depicts a single inlet disc pump  114  with the principle set forth above in paragraphs [0041] and [0042] applied. Disc pump  114  has impeller halves  116 ,  118  and multiple concave discs  120  and distribution cone or spreader  122 . The housing is not shown.  FIG. 11  shows a disc  120  with pins  126  but without ridges or bumps.  FIG. 12  shows a front view of a disc assembly  124  with pins  126  and a front view of spreader  122 . 
         [0044]      FIGS. 13A and 13B  show an impeller disc  128  from a side view in  13 A.  13 B is a top view of two impeller halves  130  and  132 , held together by pins or dowels  134 . The discs, comprised of a plurality of blades or veins  136 , float on pins  134 . The blades and pins can be manufactured as one piece. However, it is better if the blades float on the pins which hold the two parts together, as shown in  FIG. 13B . Optionally, bushings could be installed where the pins insert into the two halves of the impeller  130 ,  132 . This would ensure that the two cone-shaped impeller halves should never have to be replaced. All the parts needed to rebuild the entire pump could be sold as a kit. 
         [0045]      FIGS. 14A and 14B  show an impeller disc blade  136  with pins  134  and pin holders  138 , which are part of the blade  136 . The pins and blades could be made as one unit, as stated above. The pins  134  should be made of hardened steel to resist breakage. The blades  136  could be made of a softer metal to break off and not transfer energy to damage the pins. A brass bushing could be placed around the pins to protect them from wear. These bushings would be inserted around pins  134 . 
         [0046]      FIG. 15  shows one side of a single-sided pump with housing  170  and outlet pipe flange  174 . An impeller half  172  has an input shaft  173 . Bearing race  176  is part of housing  170 . Bearing  178  and sealing ring  180  seal input shaft  173  to the housing. Most designs utilize an electric motor to power the pump. In this configuration the half of the impeller that is connected to the motor shaft is stationary. All of the force generated between the two halves of the impellers push to the inlet side and seal between the high and low pressure sides. The inlet or supply line bolts to the housing with the inlet tube of the impeller being inside of the supply line. 
         [0047]      FIG. 16  shows the other side of the single-sided pump shown in  FIG. 15 . There is impeller  182 , sealing ring  186 , housing  184 , pipe flange  185 , bearing  188  and sealing ring  190  which seal inlet tube  187  to housing  170 , shown in  FIG. 15 . 
         [0048]      FIG. 17  shows housing  200  with multiple studs  202  for connection, as best shown in  FIG. 1  as housing  16 . There is a weep hole  204  in the intake side of housing  200 .  FIG. 18  shows a cut through the intake side of housing  200 . There is a shoulder  205  and the weep hole  204  in the intake side of housing  200 . A canal  208  which starts at air gap  212  and ends at the weep hole outlet  210 . If liquid passes through canal  208 , it indicates a leak at seal  206 . The pump then needs to be disassembled and a new seal put in place. 
         [0049]    The pump principle of this invention can be applied equally to turbines. When the impeller is configured so that the constriction is in the center and flow is reversed, torque will be applied at the output tubes, or tube and shaft if used in a single-sided configuration. 
         [0050]    Referring to  FIG. 19 , there is a diagram which depicts the basic flow of a turbine having an input  250  and a dual outlet  254  and  256 .  FIG. 20  shows a basic turbine  258  with an input  260  and an output  262 , a dual output using the same principles as the pump. 
         [0051]    Referring to  FIG. 20  there is shown an exploded view of a turbine. A sprocket, gear or pulley  220  is designed to apply torque to the equipment. There is an output shaft seal  222 , an output shaft bearing  224 , and an output shaft housing  226 . An internal sealing ring  228  on the output shaft side keeps internal pressure from contaminating bearing  224 . One half  230  of the impeller is on the output shaft side. The center section  231  of the housing has an input flange  232 . On the output side is the other impeller half  234 , the two impeller halves facing away from each other. There is an output side internal sealing ring  236  at output tube  235 . The output side housing  238  is complete with a flange  239  for the output pipe or tubing. There is an output tube or pipe bearing  240  and an output tube seal  242 . 
         [0052]    Housings  232  and  236  could be combined to reduce production costs, as seen with the pump single side version. Impeller discs or blades and pins are installed between impeller halves  230  and  234  so that the constriction is at the inside of the impeller at the outlet tube or tubes. 
         [0053]    While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention. While various embodiments may have been described as providing advantages or being preferred over other embodiments with respect to one or more desired characteristics, as one skilled in the art is aware, one or more characteristics may be compromised to achieve desired system attributes, which depend on the specific application and implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. The embodiments described herein that are described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications.
A two piece impeller centrifugal pump comprising two halves of an impeller facing each other within a volute, a housing having two sides, one side adjacent each impeller half and having an inlet and an outlet, a motor mounted on the housing, the motor driving both impeller halves, for pumping fluid or material from the inlet to the outlet, the housing and the impeller halves having a sealing surface where they contact each other, the centrifugal force of the impeller forcing the fluid or material outward, pushing the two impeller halves outward against the housing.