Image Number 2 for United States Patent #5137368.
A viscous fluid pumping system having a pair of opposing gears (130, 132) is provided in a housing (32) disposed above an inlet port (73) in a follower plate (70). The follower plate (70) is dimensioned to sealingly fit in a container or drum (D) filled with highly-viscous fluid. In operation, the gears generate a vacuum between the follower plate (70) and the viscous fluid, allowing atmospheric pressure to press the follower plate into the viscous fluid. This, in turn, forces the fluid through the inlet port (73) and into the gears (130, 132). The gears exert high shear forces and localized heating to the fluid, decreasing its viscosity. The fluid exits the system through an outlet in the gear housing. The pumping system may use two such pumps working in conjunction or incorporate a single such pump with a valve structure for recycling fluid through itself.