Patent ID: 6889871

Claim:
A method of transferring an abrasive and/or low viscosity fluid in a two part polyurethane foam making process comprising: pumping the abrasive and/or low viscosity fluid comprising constituent parts of the two part polyurethane foam, the abrasive and/or low viscosity fluid having a viscosity of less than about 10 centipoise, wherein the pumping action is effectuated by using an internally generated rotor set which comprises in combination: an inner rotor including a support having a predetermined number of fragmental cylindrical recesses equally spaced about its periphery and a rigid cylindrical tooth member received in each recess in rotational sliding contact therewith, each tooth member having substantially the same diameter as the corresponding recess, a portion of each tooth member projecting from the periphery, and an internally toothed outer rotor formed as the conjugate of the inner rotor, having simultaneous rolling engagement with all of the tooth members and having a number of teeth one greater than the predetermined number.