Fluid pump mechanical seal

Abstract

A fluid pump having a pump motor, pump housing, and pump seal enclosure disposed between the pump motor and the pump housing. A pump drive shaft is rotatably driven by the pump motor and extends through the pump seal enclosure and a drive shafting opening into a pumping chamber of the pump housing. A drive shaft seal assembly is disposed within the pump seal enclosure and includes a spring seat, rotary ring, stationary ring, and compressible spring each disposed coaxially with the drive shaft. The spring seat includes a first alignment mechanism and the rotary ring includes a second alignment mechanism for engaging the first alignment mechanism. The stationary ring is fastened to the pump seal enclosure adjacent the drive shaft opening, and the compressible spring biases the rotary ring against the stationary ring.

1 . A fluid pump comprising:
 a pump motor;   a pump housing having an internal pumping chamber, a suction orifice in flow communication with the pumping chamber, a discharge orifice in flow communication with the pumping chamber, and a drive shaft opening;   a pump seal enclosure disposed between the pump motor and the pump housing;   a pump drive shaft rotatably driven by the pump motor and extending through the pump seal enclosure and the drive shafting opening into the pumping chamber; and   a drive shaft seal assembly disposed within the pump seal enclosure, the drive shaft seal assembly including:
 a spring seat fastened to the drive shaft, the spring seat being disposed coaxially with the drive shaft and adjacent the pump motor and further having a first alignment mechanism, 
 a rotary ring disposed coaxially with the drive shaft and having a second alignment mechanism for engaging the first alignment mechanism, 
 a stationary ring disposed coaxially with the drive shaft and fastened to the pump seal enclosure adjacent the drive shaft opening, and 
 a compressible spring disposed coaxially with the drive shaft between the spring seat and the rotary ring, wherein the spring biases the rotary ring against the stationary ring. 
   
     
     
         2 . The fluid pump of  claim 1 , wherein the spring seat is fastened to the drive shaft by at least one set screw. 
     
     
         3 . The fluid pump of  claim 1 , further comprising a washer disposed coaxially with the drive shaft and adjacent the stationary ring. 
     
     
         4 . The fluid pump of  claim 3 , wherein the washer and stationary ring are non-rotatably fastened to the pump seal enclosure by at least one set screw. 
     
     
         5 . The fluid pump of  claim 1 , further comprising an O-ring disposed between the stationary ring and the pump housing. 
     
     
         6 . The fluid pump of  claim 1 , wherein substantially no pumped fluids enter the pump seal enclosure during normal operation of the pump. 
     
     
         7 . The fluid pump of  claim 1 , wherein substantially no pumped fluids contact the spring seat, the compressible spring, or the rotary ring during normal operation of the pump. 
     
     
         8 . The fluid pump of  claim 1 , wherein the stationary ring comprises a ceramic material. 
     
     
         9 . The fluid pump of  claim 1 , wherein the rotary ring comprises a graphite material. 
     
     
         10 . The fluid pump of  claim 1 , wherein the first alignment mechanism of the spring seat includes at least one alignment rib and the second alignment mechanism of the rotary ring includes at least one slot for receiving and engaging the at least one alignment rib. 
     
     
         11 . A fluid gear pump comprising:
 a pump motor;   a pump housing having an internal pumping chamber, a suction orifice in flow communication with the pumping chamber, a discharge orifice in flow communication with the pumping chamber, and a drive shaft opening;   a pump seal enclosure disposed between the pump motor and the pump housing;   a pump drive shaft rotatably driven by the pump motor and extending through the pump seal enclosure and the drive shafting opening into the pumping chamber;   a drive gear, having a plurality of drive gear teeth, disposed within the pumping chamber and rotatably driven by the drive shaft;   an idler gear, having a plurality of idler gear teeth intermeshed with the drive gear teeth, disposed within the pumping chamber and attached to an idler shaft disposed within the pumping chamber; and   a drive shaft seal assembly including:
 a spring seat fastened to the drive shaft, the spring seat being disposed coaxially with the drive shaft and adjacent the pump motor and further having a first alignment mechanism, 
 a rotary ring disposed coaxially with the drive shaft and having a second alignment mechanism for engaging the first alignment mechanism of the spring seat, 
 a stationary ring disposed coaxially with the drive shaft and fastened to the pump seal enclosure adjacent the drive shaft opening; and 
 a compressible spring disposed coaxially with the drive shaft and between the spring seat and the rotary ring, wherein the spring biases the rotary ring against the stationary ring. 
   
     
     
         12 . The fluid gear pump of  claim 11 , wherein the spring seat is fastened to the drive shaft by at least one set screw. 
     
     
         13 . The fluid gear pump of  claim 11 , further comprising a washer disposed coaxially with the drive shaft and adjacent the stationary ring. 
     
     
         14 . The fluid gear pump of  claim 13 , wherein the washer and stationary ring are non-rotatably fastened to the pump seal enclosure by at least one set screw. 
     
     
         15 . The fluid gear pump of  claim 11 , further comprising an O-ring disposed between the stationary ring and the pump housing. 
     
     
         16 . The fluid gear pump of  claim 11 , wherein substantially no pumped fluids enter the pump seal enclosure during normal operation of the pump. 
     
     
         17 . The fluid gear pump of  claim 11 , wherein substantially no pumped fluids contact the spring seat, the compressible spring, or the rotary ring during normal operation of the pump. 
     
     
         18 . The fluid gear pump of  claim 11 , wherein the stationary ring comprises a ceramic material. 
     
     
         19 . The fluid gear pump of  claim 11 , wherein the rotary ring comprises a graphite material. 
     
     
         20 . The fluid gear pump of  claim 11 , wherein the first alignment mechanism of the spring seat includes at least one alignment rib and the second alignment mechanism of the rotary ring includes at least one slot for receiving and engaging the at least one alignment rib.