Abstract:
A high-capacity fluid pump comprising a dedicated lubrication system in fluid communication with the pump&#39;s drive assembly to reduce wear of internal components within the gearbox, as well as a drive shaft-supported impeller and outboard head to reduce deflection. Moreover, the blades of the outboard head are preferably shaped to decrease the inlet&#39;s cross section and stabilize incoming fluid, thereby reducing cavitation, pre-rotation, and turbulent flow at the pump inlet and increasing the overall velocity of incoming fluid.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional application No. 62/086,590, filed Dec. 2, 2014, which is incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Fire pumps are utilized to transfer water from either a pumper/tanker fire engine or an outside source (e.g., a fire hydrant or pond) to a burning residential or industrial building. Traditional fire pumps comprise two major assemblies: a drive assembly and fluid pump assembly. The drive assembly features a gearbox for transmitting power from the power source to the pump assembly. Meanwhile, the fluid pump assembly features a an impeller coupled to a pump body, with the pump body controlling and directing the flow of water from the inlet side to the discharge side of the impeller. 
         [0003]    Traditional fire pumps typically use a passive splash lubrication system to oil gears, bearings, and other moving parts within the gearbox. In a splash lubrication system, a bottom-up approach is utilized to move oil within the gearbox. Oil resides in an oil pan at the bottom of the gearbox and a moving gear or dipper splashes oil up into the gearbox and onto other moving parts that, in turn, splash oil onto other moving parts located distally from the oil pan. 
         [0004]    To quickly extinguish a large-scale fires in industrial or municipal environments, it is desirable to move the maximum amount of water available onto the burning combustibles in the shortest amount of time. High-capacity fluid pumps (e.g., at least about 5000 gal./min. at 150 psi) can move significantly greater amounts of water and other fluids in the same amount of time as compared to traditional, regular capacity fire pumps. In the context of a fire, this can help save valuable property and lives. 
         [0005]    But high-capacity fluid pumps typically have significant power requirements and operate at increased temperatures and pressures. These factors contribute to greater wear of drive and pump components. Increased wear, in turn, reduces the useful life of the pump as well as increases both service downtime and component replacement costs. This increased wear in high-capacity fluid pumps has been traced to two primary causes: 1) inadequate lubrication within the pump&#39;s drive assembly; and 2) significant deflection of the fluid pump assembly components when operated at high rotational velocities. Moreover, high-capacity fluid pumps have been shown to be more susceptible to cavitation, pre-rotation, and turbulent flow at the pump inlet than traditional capacity fire pumps, thereby decreasing the overall efficiency of the fluid pump. 
       SUMMARY 
       [0006]    The high-capacity fluid pump of the present invention features a dedicated lubrication system in fluid communication with the pump&#39;s drive assembly to reduce wear of internal components within the gearbox, as well as a drive shaft-supported impeller and outboard head to reduce deflection within the fluid pump assembly as well as deflection of the fluid pump assembly with respect to the drive assembly. Moreover, the blades of the outboard head are preferably shaped to decrease the inlet&#39;s cross section, thereby reducing cavitation, pre-rotation, and turbulent flow at the pump inlet and increasing the overall velocity of incoming fluid. By incorporating a dedicated lubrication system, adequately supporting the impeller and outboard head of the fluid pump assembly, and reducing turbulent flow at the pump inlet, the high-capacity fluid pump of the present invention exhibits improved durability and efficiency compared to conventional high-capacity fluid pumps. 
         [0007]    In an embodiment of the high-capacity fluid pump of the present invention, the lubrication system can comprise an oil pump for supplying oil or other lubricants at or near the gears, bearings, and other moving parts in need of lubrication. The lubrication system may further comprise a cooler to further reduce wear-inducing temperatures and prevent degradation of the lubricant. 
         [0008]    For example, lubricant is preferably circulated through a drive assembly comprising gears. In one form, a lubricant pump draws lubricant from a lubricant collection container, such as an oil pan. The lubricant is preferably filtered and applied directly on, or proximate to, one or more gears, bearings, or other moving parts. Lubricant then falls back through the drive assembly, further lubricating other moving parts to which the lubricant comes in contact, until it collects in the lubricant collection container to repeat the cycle. In some forms, splash lubrication may supplement or act as a backup to the lubrication system. 
         [0009]    In an embodiment of the high-capacity fluid pump of the present invention, the impeller may be supported and stabilized by positioning it on the drive shaft between a biasing member and a nut. The outboard head may be supported and stabilized by attaching the drive shaft to a sacrificial bushing housed within the outboard head. 
         [0010]    In an embodiment of the high-capacity fluid pump of the present invention, the fluid pump can feature blades positioned at the inlet to help promote laminar flows by preventing pre-rotation and forcing fluid entering the inlet to adopt a straight path. Drag caused by the blades is reduced by curving the side of the blades facing the incoming fluid. Moreover, the shape of the fluid pump inlet itself, such as an outboard head, can also increase performance and efficiency by accelerating fluid into an impeller eye, further reducing pre-rotation and, in effect, “turbocharging” the impeller. Because the velocity of a given volume of fluid increases as its cross section decreases, the cross section of the inlet is preferably smaller than the pump&#39;s fluid connection to a tank or other fluid source. 
         [0011]    For example, an inlet may be divided into two or more apertures by one or more blades having a length. The length of the blades is longitudinal to the flow of fluid entering the inlet. The blades prevent pre-rotation by dividing the inflowing fluid and preventing the fluid from rotating about a central axis. Blades and a central member may be preferably positioned within the inlet to decrease the inlet&#39;s cross section, thereby increasing the velocity of incoming fluid. 
         [0012]    The invention may take many forms. For example, in a first foini, a high-capacity water pump may comprise a drive assembly; a fluid pump assembly; and a lubrication system. The drive assembly may comprise an input drive, a output drive shaft, and at least one gear or bearing. The fluid pump assembly may comprise a head comprising an inner diameter, three or more fixed blades, a central nose comprising a cavity shaped to house a rotatable sacrificial bushing, and an inlet, wherein the inlet consists of three or more apertures defined by the inner diameter, nose, and blades; an impeller, and a volute comprising an outlet. In one form, the output drive shaft is operably connected to the impeller and attached to the sacrificial bushing, thereby providing a force at a distal end of the output drive shaft resisting deflection of the head. Forces that can lead to such deflection include the weight of the fluid pump assembly itself, the immense horsepower applied to the fluid pump assembly by the drive assembly, and the reactive force of the water exiting the fluid pump assembly. The lubrication system is preferably in fluid communication with the drive assembly, and a lubricant flow path preferably includes at least a lubricant pump and the at least one gear or bearing. A water flow path preferably includes at least the inlet, impeller, and outlet. The blades are preferably shaped to prevent pre-rotation of incoming water, such that there is substantially laminar flow across at least a portion of the inlet. 
         [0013]    In a second form, a pump may comprise a drive assembly with a drive shaft; a fluid pump assembly; and a lubrication system. The lubrication system is preferably in fluid communication with the drive assembly and may comprise a lubricant pump. The fluid pump assembly comprising an inlet with a head, wherein the head comprises at least one fixed blade dividing the head into least two apertures. The head may be supported by an end of the drive shaft. 
         [0014]    In a third form, an apparatus for moving fluid may comprise a gearbox and a lubrication system. The lubrication system is preferably in fluid communication with the gearbox. Lubricant may be pressurized and adopt a flow path including one or more of the following: a filter, a lubricant pump, a cooler, a splitter, a gearbox inlet port, at least one gear or bearing, a lubrication container positioned at a base of the gearbox, and a gearbox outlet port. The gearbox may operably coupled to a fluid pump having a maximum flow rate of at least 2500 gal./min., more preferably at least 3000 gal./min. and most preferably 5000 gal./min. 
         [0015]    In a fourth form, a system for moving fluid may comprise a drive shaft and a fluid pump assembly. The fluid pump assembly may comprise an inlet and a head, wherein the head comprises at least one fixed blade dividing the head into least two apertures. The inlet head is preferably supported by an end of the drive shaft. 
         [0016]    In a fifth form, a method may comprise pumping lubricant to a first end of a drive assembly; circulating lubricant through a lubricant collection container positioned at a second end of the drive assembly; and filtering the lubricant. 
         [0017]    In a six form, a method may comprise rotating an impeller; drawing fluid into an inlet having one or more blades; and preventing pre-rotation across at least a portion of the inlet. 
         [0018]    In any or all of the foregoing forms and embodiments, the fluid pump may have a maximum flow rate of at least 2500 gal./min., more preferably at least 3000 gal./min., and most preferably 5000 gal./min. or greater. 
         [0019]    In any or all of the foregoing forms and embodiments, an impeller may be positioned on a drive shaft between a biasing member and a support member, wherein the impeller is positioned on the drive shaft such that the biasing member is at least partially compressed. A head may be supported by an end of the drive shaft. 
         [0020]    In any or all of the foregoing forms and embodiments, lubricant is preferably filtered. A flow path may include at least the lubricant pump and at least one moving part within the drive assembly. The flow path may further include a lubricant filter. 
         [0021]    In any or all of the foregoing forms and embodiments, an inlet, and portions thereof, is preferably shaped to prevent pre-rotation of water entering the inlet. For example, the blades may be shaped to substantially reduce pre-rotation of fluid around a central axis of the inlet. One way to achieve this is by having the blade have a length in a direction orthogonal to a plane of the inlet, wherein the length is sufficient to substantially reduce pre-rotation of fluid around a central axis of the inlet. Exact sizes will depend on the size of the pump. The inlet preferably has a cross section smaller than the cross section of a proximate portion of the connection to the fluid source. For example, the head may comprise three blades and a central support member. 
         [0022]    In any or all of the foregoing founs and embodiments, a head may comprises a cavity shaped to house a rotatable sacrificial bushing, and wherein the output drive shaft is attached to the sacrificial bushing. 
         [0023]    The above summary is not intended to describe each illustrated embodiment or every possible implementation. It is not an exhaustive overview of the details disclosed herein. Nor is it intended to identify key or critical elements of the invention or to delineate the scope of the invention. These and other features, aspects, and advantages of the subject matter of this disclosure will become better understood in view of the following description, drawings, and claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views, and which, together with the detailed description below, are incorporated in and form part of the specification, serve to illustrate further various embodiments and to explain various principles and advantages in accordance with the present invention: 
           [0025]      FIG. 1  is a front perspective view of one embodiment of a pump in a split drive configuration. 
           [0026]      FIG. 2  is a rear perspective view of the pump of  FIG. 1 . 
           [0027]      FIG. 3  is an exploded view of the pump of  FIG. 1 . 
           [0028]      FIGS. 4A-B  are lubricant flow diagrams. 
           [0029]      FIG. 4C  is a coolant flow diagram. 
           [0030]      FIG. 5  is a front perspective view of one embodiment of a pump in a direct drive configuration. 
           [0031]      FIG. 6  is a rear perspective view of the pump of  FIG. 5 . 
           [0032]      FIG. 7A  is an exploded view of one embodiment of an output drive assembly and fluid pump assembly. 
           [0033]      FIGS. 7B-C  are front and rear views of the outboard head of  FIG. 7A . 
           [0034]      FIG. 7D  is a detail view of  FIG. 7C . 
           [0035]      FIG. 8  is a cross section of one embodiment of a fluid pump assembly. 
       
    
    
     DESCRIPTION OF REFERENCE NUMERALS 
       [0036]      100  . . . high-capacity pump 
         [0037]      150  . . . motor 
         [0038]      160  . . . tank 
         [0039]      200  . . . drive assembly 
         [0040]      205  . . . gearbox 
         [0041]      210  . . . pressure release valve 
         [0042]      220  . . . front input drive 
         [0043]      221  . . . input drive housing 
         [0044]      222  . . . input drive gear 
         [0045]      223  . . . input drive cap 
         [0046]      230  . . . transmission assembly 
         [0047]      232  . . . transmission shifter 
         [0048]      234  . . . transmission shaft 
         [0049]      240  . . . accessory drive 
         [0050]      241  . . . accessory drive cap 
         [0051]      242  . . . accessory drive gear 
         [0052]      250  . . . upper output drive 
         [0053]      251  . . . upper output drive cap 
         [0054]      252  . . . upper output gear 
         [0055]      253  . . . upper output bearing assembly 
         [0056]      254  . . . drive shaft 
         [0057]      254   a  . . . threaded portion of drive shaft  254   
         [0058]      255  . . . nut 
         [0059]      260  . . . idler gear 
         [0060]      270  . . . lower output drive 
         [0061]      300  . . . lubrication system 
         [0062]      302  . . . gearbox inlet port 
         [0063]      303  . . . gearbox outlet port 
         [0064]      304  . . . hose 
         [0065]      310  . . . lubricant pump 
         [0066]      312  . . . lubricant pump inlet hose 
         [0067]      314  . . . lubricant pump outlet hose 
         [0068]      316  . . . lubricant collection container 
         [0069]      318  . . . lubricant filter 
         [0070]      320  . . . directional port 
         [0071]      330  . . . splitter 
         [0072]      332  . . . pressure sensor 
         [0073]      333  . . . pressure sensor line 
         [0074]      334  . . . pressure gauge 
         [0075]      340  . . . cooler 
         [0076]      342  . . . cooler inlet hose 
         [0077]      344  . . . cooler outlet hose 
         [0078]      346  . . . cooler inlet port 
         [0079]      348  . . . cooler outlet port 
         [0080]      400  . . . fluid pump assembly 
         [0081]      410  . . . inboard head 
         [0082]      420  . . . impeller 
         [0083]      430  . . . volute 
         [0084]      432  . . . pump outlet 
         [0085]      433  . . . aperture for cooler outlet hose  344   
         [0086]      440  . . . outboard head 
         [0087]      442  . . . central support member 
         [0088]      443  . . . first side (curved), nose 
         [0089]      444  . . . sacrificial bushing 
         [0090]      445  . . . blade 
         [0091]      446  . . . first side (curved) 
         [0092]      447  . . . second side (flat) 
         [0093]      448  . . . aperture for fluid entering volute  430   
         [0094]      450  . . . O-ring 
         [0095]      452  . . . gasket 
         [0096]      454  . . . wear ring 
         [0097]      456  . . . biasing member 
         [0098]      457  . . . seal 
       DESCRIPTION 
       [0099]    A high-capacity fluid pump featuring a dedicated lubrication system and stabilized fluid pump assembly components is described herein. The description which follows, and the embodiments described therein, is provided, by way of illustration of examples of particular embodiments of principles and aspects of the present invention. These examples are provided for the purposes of explanation and not of limitationof those principles of the invention. In the description that follows, like parts are marked throughout the specification and the drawings with the same respective reference numerals. As used herein, the term “about” or “approximately” applies to all numeric values, whether or not explicitly indicated. These terms generally refer to a range of numbers that one of skill in the art would consider equivalent to the recited values (i.e., having the same function or result). In many instances these temis may include numbers that are rounded to the nearest significant figure. Relational terms such as first and second, top and bottom, right and left, and the like may be used solely to distinguish one component or feature from another component or feature without necessarily requiring or implying any actual such relationship or order between such components and features. 
         [0100]    A high-capacity pump  100  designed according to this disclosure may benefit from reduced wear and increased efficiency. Pump  100  may comprise a drive assembly  200 , lubrication system  300 , and fluid pump assembly  400 . 
         [0101]    A dedicated lubrication system  300  can help reduce wear in a drive assembly  200 . Lubrication system  300  preferably pumps lubricant directly on or proximate to gears, bearings, and other moving parts within drive assembly  200 . If lubrication system  300  comprises a lubrication collection container  316 , such as an oil pan, splash lubrication can operate in parallel with the lubrication system  300  and acts as a backup. Optimal lubrication can reduce wear and promote uniformity of wear across components while increasing their useful life. A lubrication system  300  comprising a cooler  340  can further reduce wear-inducing temperatures and prevent lubricant degradation. 
         [0102]    Wear may be further reduced within an adequately supported and stabilized fluid pump assembly  400 . As shown in  FIGS. 7A and 8 , fluid pump assembly  400  comprises an impeller  420  and outboard head  440 . In one embodiment, impeller  420  is rotated by a drive shaft  254 , which has a threaded portion  254   a.  Impeller  420  is positioned on drive shaft  254  between a biasing member  456  and a nut  255 , which engages threaded portion  254   a.  Because nut  255  has a greater outer diameter than an inner diameter of the impeller  420 , tensioning nut  255  loads (e.g., compresses) biasing member  456  and thereby stabilizes the impeller  420 , preventing deflection. In this or an alternative embodiment, drive shaft  254  also supports and stabilizes outboard head  440 . Head  440  comprises central support member  442  housing a sacrificial bushing  444  that is engaged to the threaded portion  254   a.    
         [0103]    Increased efficiency may be achieved by increasing laminar flows of fluid across the inlet of fluid pump assembly  400 . In one embodiment, the outboard head  440  comprises one or more blades  445  that prevent pre-rotation of fluid entering the inlet. In some forms, central support member  442  comprises a nose member  443  that is curved and to which blades  445  are connected. Blades  445  may also have a curved side  446  facing fluid entering the inlet, reducing drag. 
         [0104]    Turning to the figures,  FIGS. 1 and 2  show one form of a high-capacity pump  100  in a split drive configuration suitable for installation on a fire apparatus (not shown), e.g., a fire truck. The pump  100  comprises a drive assembly  200 , a lubrication system  300 , and fluid pump assembly  400 . 
         [0105]    The split drive configured drive assembly  200  is shown in an exploded view in  FIG. 3 . The motor of a fire apparatus (not shown) may be operably coupled to front input drive  220  to rotate input drive gear  222 . Transmission assembly  230 , including transmission shifter  232  and transmission shaft  234 , causes the input drive gear  222  to engage either lower output drive  270 , accessory drive gear  242 , or idler gear  260 . Lower output drive  270  may be operably coupled to an axle (not shown) to turn the wheels of a fire apparatus. The accessory drive  240  is optional and may be coupled to a shaft (not shown) or other device to operate fire apparatus accessories, such as a hydraulic pump to drive a foam system or air compressor. Because idler gear  260  may engage both input drive gear  222  and upper output gear  252 , it is preferably sized to optimize the operation of fluid pump assembly  400 . (This gear ratio is a function of the horsepower of the motor and the operational requirements of the fluid pump assembly  400 .) Upper output gear  252  rotates drive shaft  254 . 
         [0106]    The drive assembly  200  may also comprise a gearbox  205 . The gearbox  205  is preferably sealed such that a pressure within gearbox  205  may be greater than atmospheric pressure. The gearbox  205  may comprise pressure release valve  210 , accessory drive cap  241 , and upper output drive cap  251 . 
         [0107]    One form of a lubrication system  300 , shown in  FIGS. 1-3 and 4A , comprises an oil pump  310 . Oil pump  310  is directly connected to splitter  330 , which distributes pressurized lubricant across hoses  304 . The lubrication system  300  also comprises an oil filter  318  (not shown) positioned in or in fluid communication with an oil pan  316  (not shown). 
         [0108]    Another form of a high-capacity pump  100 , shown in  FIGS. 5-6 , may be in a direct drive configuration suitable for stationary or mobile applications with a dedicated motor  150 . The pump  100  comprises a drive assembly  200 , a lubrication system  300 , and fluid pump assembly  400 . 
         [0109]    The drive assembly  200  comprises a gearbox  205 , an input drive  220 , a gear  260 , and an output drive  250 . The size of gear  260  is a function of the horsepower of the motor and the operational requirements of the fluid pump assembly  400 . The gearbox comprises an input drive housing  221 , an input drive cap  223 , and an output drive cap  251 . 
         [0110]    As shown in  FIGS. 5-6 and 4B -C, another form of a lubrication system  300  comprising an oil pump  310  and a cooler  340 . Oil pump  310  is connected to cooler  340 , which is connected to splitter  330 . In this embodiment, cooler  340  circulates water and is connected to water tank  160  and water pump outlet  432 . The lubrication system  300  also comprises an oil filter  318  (not shown) positioned in or in fluid communication with an oil pan  316  (not shown). 
         [0111]    If an oil pump  310  is located outside gearbox  205  as shown in  FIGS. 1-3 and 5-6 , the gearbox  205  may also comprise apertures for gearbox inlet nozzles  302  and gearbox outlet nozzles  303 . The apertures for gearbox inlet nozzles  302  are preferably positioned at or near gears or other moving parts of drive assembly  200 . The aperture for gearbox outlet nozzle  303  is preferably positioned near a lubrication collection container, such as an oil pan. 
         [0112]    For example, as shown in  FIGS. 1-3 , the gearbox  205  comprises seven apertures for gearbox inlet nozzles  302  located proximally to front input drive  220  (one aperture), accessory drive  240  (one aperture), upper output drive  250  (three apertures), idler gear  260  (hidden, one aperture), and lower output drive  270  (one aperture). By contrast,  FIGS. 5-6  shows gearbox  205  with five apertures for gearbox inlet nozzles  302  located proximally to an output drive (three apertures), idler gear  260  (hidden, one aperture), an input drive cap  223  (one aperture). 
         [0113]    Forms of the fluid pump assembly  400  are shown in  1 - 2 ,  5 - 6 ,  7 A-D and  8  and are suitable for both split drive, direct drive, and other configurations. As shown in  FIGS. 7A and 8 , a fluid pump assembly  400  may comprise an inboard head  410 , an impeller  420 , a volute  430 , and an outboard head  440 . 
         [0114]    One way to couple a drive assembly  200  to a fluid pump assembly  400  is through the attachment of upper output bearing assembly  253  to inboard head  410 . Mechanical seal  457  preferably forms a fluid impermeable seal between fluid pump assembly  400  and drive assembly  200 , preventing water or other fluid from entering drive assembly  200  and preventing lubricant from entering fluid pump assembly  400 . Seal  457  is a wear component that should be replaced from time to time. 
         [0115]    Gaskets  452  and O-rings  450  seal attachments between the volute  430  and inboard head  410  and outboard head  440 . Wear rings  454  are positioned between the impeller  420  and inboard head  410  and outboard head  440 . Wear rings  454  are wear components that should be replaced from time to time. 
         [0116]    Drive shaft  254  rotates impeller  420 . Drive shaft  254  comprises a non-threaded portion (which may comprise a notch to engage impeller  420 ) and a threaded portion ( 254   a ). A biasing member  456 , such as a spring, may be positioned on the non-threaded portion proximate to inboard head  410 . Nut  255  may engage threaded portion  254   a  of drive shaft  254  proximate to outboard head  440 . Impeller  420  may be positioned between and abut biasing member  456  and nut  255 , such that tightening nut  255  loads biasing member  456  and stabilizes impeller  420 . Nut  255  may be a jack nut and is preferably formed from a material that is softer than the material composing the impeller  420 ; for example, if impeller  420  is steel, nut  255  may be brass. 
         [0117]    As shown in  FIGS. 2 and 7B -D, outboard head  440  has a first side and second side. On the first side of outboard head  440 , best seen in  FIGS. 2 and 7C -D, head  440  comprises an inlet of three apertures  448 . The inlet is defined by an inner diameter of the outboard head  440  divided by a central support member  442  (with a curved nose  443 ) connected to three blades  445 , each preferably having a substantially curved side  446 . 
         [0118]    On the second side of outboard head  440 , as shown in  FIG. 7B , the central support member  442  has a cavity that houses a sacrificial bushing  444 . The second side  447  of blades  445  are preferably substantially flat (i.e., not curved). Onboard head  440  is attached to volute  430  and sacrificial bushing  444  is attached to threaded portion  254   a  of drive shaft  254 . 
         [0119]    Sacrificial bushing  444  supports outboard head  440  and prevents deflection of the fluid pump assembly  400 . Sacrificial bushing  444  rotates with drive shaft  254  and a thin film of fluid separates it from central support member  442 . Sacrificial bushing  444  is preferably formed from a material that is softer than the material composing the central support member  442 ; for example, if central support member  442  is steel, sacrificial bushing  444  may be brass. 
         [0120]    Blades  445  prevent pre-rotation of fluid entering the inlet of outboard head  440  and promote laminar flow across the inlet and into the impeller  420 . Blades  445  preferably have a length equal to or less than the length of outboard head  440  (measured along its central axis). 
         [0121]    Various founs of the invention may have various flow paths for fluids moving through or within the high-capacity pump  100 , including fluid moving through fluid pump assembly  400 , lubricant moving within drive assembly  200  and lubrication system  300 , and/or coolant moving through cooler  340 . 
         [0122]    One method of moving fluid through a high-capacity pump  100  comprises rotating an impeller  420 . Impeller  420  creates low pressure at an inlet of fluid pump assembly  400  (within head  440 ), causing fluid to move from a tank  160  through the inlet and into impeller  420 . Impeller  420  accelerates the fluid by applying a centrifugal force on the fluid within a volute  430 . Fluid exits at high speed and pressure at pump outlet  432  (within volute  430 ). 
         [0123]    One method of moving lubricant within drive assembly  200  comprises pumping lubricant from an oil pan  316 . In one embodiment, see  FIG. 4A , oil pump  310  draws lubricant through filter  318  positioned in or in fluid communication with oil pan  316 , out gearbox outlet port  303 , through oil pump  310 , across one or more gearbox inlet ports  302 , and into gearbox  205 . In another embodiment, see  FIG. 4B , oil pump  310  draws lubricant through filter  318  positioned in or in fluid communication with oil pan  316 , out gearbox outlet port  303 , through oil pump  310 , cooler  340 , and splitter  330 , across one or more gearbox inlet ports  302 , and into gearbox  205 . In both embodiments, once within the gearbox  205 , the lubricant lubricates gears, bearings, and other moving parts until the lubricant flows to oil pan  316  and the cycle is repeated. Splash lubrication may proceed concurrently with the lubrication system  300 . As shown in  FIGS. 1-2 and 5-6 , lubricant may also move through directional port  320 , pump inlet hose  312 , pump outlet hose  314 , splitter  330  and/or cooler  340 . 
         [0124]    One method of moving coolant, such as water or other suitable fluid, through a lubrication system  300  comprises pumping coolant and lubricant across a heat exchanger within a cooler  340 . In one embodiment, see  FIG. 4C , coolant may flow from tank  160 , through cooler  340 , and out pump outlet  432 . In another embodiment, see  FIGS. 5-6 , water may flow from tank  160 , into cooler inlet port  346 , through cooler inlet hose  342 , across a heat exchanger to absorb heat from the lubricant, through cooler outlet hoses  344 , and out cooler outlet port  348  to pump outlet  432 . 
       PROPHETIC EXAMPLE 1 
       [0125]    In a split drive configuration (see  FIGS. 1-3, 7A -D, and  8 ), about 5000 to 6500 gal./min. flows through fluid pump assembly  400 , entering through outboard head  440 , and exiting through pump outlet  432 . A fire apparatus with about 600 to 700 horsepower rotates—through drive assembly  200  and front input drive  220 —impeller  420 , which has an angular velocity of about 2000 to 2400 rotations per minute. Lubrication system  300  is in fluid communication with drive assembly  200  and operates at pressures ranging from about 15 to 30 psi. 
       PROPHETIC EXAMPLE 2 
       [0126]    In a direct drive configuration (see  FIGS. 5-8 ), about 5000 to 6500 gal./min. flows through fluid pump assembly  400 . An engine  150  with about 600 to 800 horsepower engages—through drive assembly  200 —impeller  420 , which has an angular velocity of about 2000 to 2400 rotations per minute. Lubrication system  300  is in fluid communication with drive assembly  200  and operates at pressures ranging from about 15 to 30 psi. 
       PROPHETIC EXAMPLE 3 
       [0127]    In either or both of the foregoing examples, lubrication system  300  may also comprise cooler  340  to maintain operating lubrication temperatures below about 180° F. 
         [0128]    Many components described in this disclosure may be optional, regardless of whether they are identified as such. For illustrative purposes, however, some components may be optional or unnecessary depending on the application for which the pump  100  will be used. 
         [0129]    For example, unlike the drive assembly  200  of  FIGS. 1-3 , the drive assembly  200  of  FIGS. 5-6  does not have an accessory drive  240 , a lower output drive  270 , or a transmission assembly  230 . These are optional components for certain applications. 
         [0130]    Likewise, some lubrication systems  300  may not comprise a splitter  330  (see  FIG. 4A ) or a filter  318 . Further, in some embodiments, all or part of the lubrication systems  300  may be located within a gearbox  205 , eliminating the need for gearbox inlet ports  302  and gearbox outlet port  303 . 
         [0131]    While specific embodiments have been described above, many alternative embodiments may be suitable in view of the objects of the foregoing disclosure. 
         [0132]    Although the pump  100  lends itself to large-scale industrial firefighting applications, it could also be used in a municipal setting. 
         [0133]    In alternative embodiments, each drive component with a single aperture for a gearbox inlet port  302  may have plural apertures for plural ports  302 . Alternatively, a drive component having plural apertures for plural ports  302  may only have one at that location on the gearbox  205 ; in which case, the single gearbox inlet port  302  preferably has a wide spraying nozzle to maximize distribution of lubricant within gearbox  205 . 
         [0134]    Numerous modifications, substitutions, and omissions may be made to the order of flow within a lubrication system  300 . For example, filter  318  may be located outside gearbox  205 ;  FIG. 4A  would be modified to show:  205 → 316 → 303 → 318 → 310 → 302 → 205 . Numerous alternative orders exist and all are within the scope of this disclosure. Indeed, directional ports  320 , splitters  330 , and coolers  340  may be interposed almost anywhere between an oil pump  310  and gearbox  205 ; or they may be omitted. 
         [0135]    Under appropriate conditions, all or part of the lubrication systems  300  of either of the illustrative high-capacity pumps  100  shown may be substituted for the other. For example, the lubrication system  300  of  FIGS. 1-3  (without cooler and/or additional hoses  304 ) may be substituted with suitable modifications for the lubrication system  300  of  FIGS. 5-6  (with cooler  340  and/or fewer hoses  304 ) for the high-capacity pump  100  of  FIGS. 5-6 . And vice versa. 
         [0136]    Cooler  340  may circulate a fluid other than water, such as radiator fluid, refrigerant, or other suitable fluid. 
         [0137]    Any container suitable for holding oil or other lubricant may serve as an oil pan or lubrication collection pan or container, including a portion of the gearbox  205  itself. 
         [0138]    Blades  445  may have two flat sides, two curved sides, or some blades may have curved or flat sides while others may or may not. 
         [0139]    Finally, many fluid pumps (including high, regular, and smaller capacity pumps) may be retrofitted with all or part of lubrication system  300 , and/or with all or some of the components supporting and stabilizing the fluid pump assembly  400 , and/or an inlet with one or more blades  445 . One of ordinary skill with the benefit of this disclosure would know what modifications, if any, would be necessary to retrofit such existing or future developed systems. 
         [0140]    The foregoing description of the embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form(s) disclosed, and many modifications and other embodiments of the invention set forth in this disclosure will be appreciated by one skilled in the art having the benefit of this disclosure. The embodiments were chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. The embodiments shown in the drawings and described above are exemplary of numerous embodiments that may be made within the scope of the appended claims. It is contemplated that numerous other configurations may be used, and the material of each component may be selected from numerous materials other than those specifically disclosed. 
         [0141]    It will be appreciated that in the development of a product or method embodying the invention, the developer must make numerous implementation-specific decisions to achieve the developer&#39;s specific goals, such as compliance with manufacturing and business-related constraints, that will vary from one implementation to another. Moreover, it will be appreciated that such a development effort may be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. 
         [0142]    This disclosure does not contain a glossary. No special definition of a term or phrase, i.e., a definition that is different from the ordinary and customary meaning as understood by those skilled in the art, is intended to be implied by consistent usage of the term or phrase herein. Words and phrases should be understood and interpreted to have a meaning consistent with the understanding of those words and phrases by those skilled in the relevant art and case law. For example, an embodiment comprising a singular element does not disclaim plural embodiments; i.e., the indefinite articles “a” and “an” carry either a singular or plural meaning and a later reference to the same element reflects the same potential plurality. A structural element that is embodied by a single component or unitary structure may be composed of multiple components. Ordinal designations (first, second, third, etc.) merely serve as a shorthand reference for different components and do not denote any sequential, spatial, or positional relationship between them. Words of approximation such as “about,” “approximately,” or “substantially” refer to a condition or measurement that, when so modified, is understood to not necessarily be absolute or perfect but would be considered close enough by those of ordinary skill in the art to warrant designating the condition as being present or the measurement being satisfied. For example, a numerical value or measurement that is modified by a word of approximation, such as “about” or “approximately,” may vary from the stated value by 1, 2, 3, 4, 5, 6, 7, 10, 12, and up to 15%. 
         [0143]    It is intended that the scope of the invention be defined only by the following claims, as amended, and their equivalents.