Fluid pumping system with a continuously variable transmission

Abstract

A technique for providing a water pumping system suitable for fighting wildfire, flood mediation, sewage transport, and the like is revealed. The system includes an internal combustion engine, a CVT with an input shaft and an output shaft, and a pump with an axial flow impeller. In one variation, multiple impeller stages are used and/or several systems are daisy-chained to provide for suitable delivery of water from its source. In another form, the system is carried by an all-terrain vehicle, side-by-side, or the like, to reach remote areas that need to move water to address a hazardous condition.

What is claimed is: 
     
         1 . A method, comprising:
 providing a mobile water-pumping system to a selected site proximate to a water source, the system including: (a) an internal combustion engine, (b) a pump including an axial flow impeller positioned within a housing defining an intake and outlet, (c) a delivery conduit in sealed engagement with the outlet, and (d) a CVT including a power input shaft and an power output shaft;   driving the power input shaft of the CVT with the internal combustion engine;   rotating the axial flow impeller with the power output shaft of the CVT to operate the pump;   mechanically governing selected operations of the system with the CVT, the CVT transferring power between the power input shaft and the power output shaft in accordance with a variable turn ratio, the CVT being responsive to change in power input shaft speed and power output shaft speed to adjust the variable turn ratio; and   during the rotating of the axial flow impeller shaft, moving water from the water source through the intake and discharging the water through the delivery conduit to perform at least one of: (a) fighting fire with the water discharged from the delivery conduit, (b) wetting flammable matter in a designated area to establish a fire break, and (c) moving the water to abate an existing or threatened flood condition.   
     
     
         2 . The method of  claim 1 , in which the CVT includes a variable drive pulley, a variable driven pulley, and an endless loop, and further including:
 turning a variable drive pulley with the power input shaft, a drive pulley effective diameter increasing and decreasing in correspondence with drive pulley rotational speed increasing and decreasing;   providing a variable driven pulley connected to the power output shaft, a driven pulley effective diameter increasing and decreasing in correspondence with driven pulley rotational speed decreasing and increasing; and   conveying mechanical power between the drive pulley and the driven pulley with an endless loop encircling the drive pulley and the driven pulley to establish contact with each one, the drive pulley effective diameter and the driven pulley effective diameter collectively establishing the variable turn ratio of the CVT.   
     
     
         3 . The method of  claim 1 , which includes:
 opposing CVT operation with mechanical resistance caused by a head increase of the pump in excess of a non-negligible magnitude; and   in response to the resistance, adjusting the variable turn ratio of the CVT to maintain regulation of engine rotational speed relative to a target operating point by increasing turning of the power input shaft relative to each turn of the power output shaft, while the adjusting of the variable turn ratio slows rotation of the impeller to decrease water capacity output from the pump.   
     
     
         4 . The method of  claim 1 , which includes providing the axial flow impeller with a self-lubricious, nonferrous material along one or more edges of the impeller, the one or more edges being structured to meet an inner surface of the housing for the impeller to reduce clearance therebetween to enhance pump efficiency. 
     
     
         5 . The method of  claim 1 , which includes the axial flow impeller having a maximum diameter from about 5 inches through about 9 inches. 
     
     
         6 . The method of  claim 1 , which includes:
 carrying the system with a four wheel drive vehicle, the vehicle having a propulsion engine separate from the internal combustion engine carried with the water-pumping system;   traveling off-road over rough terrain at least five miles to reach the selected site proximate to the water source; and   conveying the water from the water source to the intake with an intake conduit, the intake conduit being coupled to the intake at one end and submerged in the water source at another end opposite the one end.   
     
     
         7 . A method, comprising:
 moving a vehicle off-road to a position relative to a water source, the vehicle carrying a pumping system including: a rotary power source, a CVT with a power input shaft and a power output shaft, and a rotodynamic pump with an operative kinetic pump rotor, an intake, and an outlet;   driving the power input shaft of the CVT with the rotary power source at an input rotational speed;   turning the rotor with the power output shaft of the CVT to receive water from the water source through the intake and provide the water to the outlet at a first water capacity;   delivering the water at the first water capacity through a conduit in fluid communication with the outlet to abate a hazardous condition including one or more of: a fire and a flood;   in response to mechanical resistance from an increase in a hydraulic head of the pump, regulating the input rotational speed relative to a target rotational speed by adjustment of a turn ratio defined with the CVT, while the adjustment slows the turning of the rotor with the power output shaft to reduce the first water capacity to a second water capacity; and   providing the water at the second water capacity through the conduit to continue to abate the hazardous condition.   
     
     
         8 . The method of  claim 7 , in which the CVT includes:
 a drive pulley with a first drive sheave portion fixed to the power input shaft and a second drive sheave portion movable relative to the first drive sheave portion;   a driven pulley with a first driven sheave portion fixed to the power output shaft and a second driven sheave portion movable relative to the first driven sheave portion;   an endless loop fit about the drive pulley and the driven pulley and contacting each of the drive pulley and driven pulley to turn therewith;   a first mechanism coupled to the drive pulley to move the second drive sheave portion toward the first drive sheave portion as drive rotary speed increases to increase drive pulley effective diameter relative to the endless loop and farther apart as the drive rotary speed decreases to decrease the drive pulley effective diameter relative to the endless loop; and   a second mechanism coupled to the driven pulley to move the second driven sheave portion away from the first driven sheave portion as driven rotary speed increases to decrease driven pulley effective diameter relative to the endless loop and closer together as the driven rotary speed decreases to increase the driven pulley effective diameter relative to the endless loop.   
     
     
         9 . The method of  claim 7 , in which the adjustment of the turn ratio includes increasing turns of the power input shaft relative to each turn of the power output shaft. 
     
     
         10 . The method of  claim 7 , which includes means for providing the adjustment of the turn ratio. 
     
     
         11 . The method of  claim 7 , in which:
 the rotary power source is a form of internal combustion engine having a horsepower rating in a range from about 300 HP through about 600 HP; and   the rotor is a form of axial flow impeller having a maximum diameter in a range from about 5 inches through about 9 inches.   
     
     
         12 . The method of  claim 11 , which includes providing the axial flow impeller with a self-lubricious, nonferrous impeller material along at least a leading edge thereof, the leading edge being structured to meet an inner surface of an impeller housing of the pump to reduce clearance therebetween to enhance pump efficiency. 
     
     
         13 . The method of  claim 7 , in which the vehicle has a propulsion engine separate from the internal combustion engine and the vehicle travels off-road at least 5 miles to reach the water source. 
     
     
         14 . An apparatus, comprising:
 an internal combustion engine with a controller and an engine power shaft, the controller regulating the engine to target a desired operating point speed;   a pump including a housing and an axial flow impeller positioned in the housing, the housing defining an intake to the impeller and an outlet from the impeller; and   a CVT including a power input shaft coupled to the engine power shaft to receive rotary engine power therefrom and a power output shaft coupled to the impeller to provide rotary power thereto, the CVT further including;
 a drive pulley with a first drive sheave portion fixed to the power input shaft and a second drive sheave portion movable relative to the first drive sheave portion; 
 a driven pulley with a first driven sheave portion fixed to the power output shaft and a second driven sheave portion movable relative to the first driven sheave portion; 
 an endless loop positioned about the drive pulley and the driven pulley and contacting each of the drive pulley and driven pulley to turn therewith; 
 a first mechanism coupled to the drive pulley to move the second drive sheave portion toward the first drive sheave portion as drive rotary speed increases to increase drive pulley effective diameter and farther apart as the drive rotary speed decreases to decrease the drive pulley effective diameter; and 
 a second mechanism coupled to the driven pulley to move the second driven sheave portion away from the first driven sheave portion as driven rotary speed increases to decrease driven pulley effective diameter and closer together as the driven rotary speed decreases to increase the driven pulley effective diameter. 
   
     
     
         15 . The apparatus of  claim 14 , which includes a vehicle with a propulsion engine separate from the internal combustion engine, the vehicle carrying the internal combustion engine, the pump, and the CVT. 
     
     
         16 . The apparatus of  claim 14 , which includes means for delivering water from the water source with the pump in a water capacity range from about 2000 GPM through about 15,000 GPM. 
     
     
         17 . The apparatus of  claim 14 , in which the axial flow impeller has a maximum diameter in a range of about 5 inches through about 9 inches. 
     
     
         18 . The apparatus of  claim 14 , in which the axial flow impeller includes a self-lubricious, nonferrous material along at least a leading edge thereof. 
     
     
         19 . The apparatus of  claim 14 , which includes:
 means for regulating engine rotary speed relative to the desired operating point despite mechanical resistance caused by a head increase of the pump; and   means for decreasing the water capacity output of the pump in response to mechanical resistance caused by the head increase of the pump to provide power to support performance of the regulating means simultaneously with the decreasing means.   
     
     
         20 . The apparatus of  claim 14 , which includes:
 an input conduit operable to sealingly engage with the intake;   an output conduit operable to sealingly engage with the outlet; and   the housing defines an elbow discharge that changes direction of water flow exiting the impeller.