Ventilated pump shaft seal

A gear pump and shaft seal combination, comprising:

• a housing assembly including a plurality of plates, and inlet and outlet ports in the housing assembly;
• a plurality of gears having intermeshing teeth, said gears supported for rotation between the plates, the inlet and outlet ports providing fluid flow into an area of expanding cavities between the teeth, and providing fluid flow out of an area of contracting cavities between the teeth, one of said gears being supported for rotation on a drive shaft, said drive shaft projecting axially through an opening in one of said plates and externally of the housing assembly to enable rotation of the gears;
• the shaft seal fixed to the one plate, and including a cylindrical body with an internal annular core having a central circular passage with a reverse internal helical or spiral groove, the central passage closely receiving an external portion of the drive shaft and the reverse internal groove providing a pumping function as the drive shaft rotates to prevent leakage of fluid from the housing along the drive shaft, the body of the shaft seal including a plurality of discrete, radially extending recesses opening along an exterior surface of the shaft seal and arranged in circumferentially-spaced relation to one another, and an annular cooling passage entirely and continuously circumferentially surrounding the internal core and fluidly connected with the radial recesses to provide passive convective cooling for the shaft seal as the drive shaft rotates.

A fluid transfer device and shaft seal combination, comprising:

• a housing including inlet and outlet ports;
• pump means supported in the housing, the inlet and outlet ports directing fluid to and away from the pump means, a rotatable drive shaft projecting axially externally of the housing operatively connected to the pump means;
• the shaft seal fixed with respect to the housing, and including a one piece, unitary body with an internal core circumferentially surrounding the shaft, the internal core including a central passage closely receiving an external portion of the drive shaft and seal means along an interior surface of the central passage for preventing fluid leakage along the drive shaft as the drive shaft rotates,
• the body of the shaft seal including a plurality of discrete, radially-extending recesses opening along an exterior side surface of the shaft seal, and a cooling chamber entirely and continuously surrounding the internal core and fluidly connected with the radial recesses to provide passive conductive cooling for the shaft seal as the drive shaft rotates.