Rotary positive displacement machine with parallel shafts - has two rotors with helical teeth, grooves and generates leading flank vector

摘要

The rotary positive displacement machine with parallel shafts has two rotors with helical teeth, helical grooves respectively. The leading flanks in the grooved rotor are generated by a vector ( ) with its origin (1) at the intersection between the pitch circle (2) and a radial line (3) through the groove root. The character of this vector is such that it reaches a min. value at between 10 and 65% of the groove depth; increases again thereafter. It reaches this value (min.) after not more than 45 deg. of rotation from the flank's outermost point; travelling along less than half the flank length.