Bi-helical toothed wheel with variable helix angle and non-encapsulated profile for a hydraulic gear apparatus

摘要

The invention relates to a bi-helical toothed wheel (1) with non-encapsulating profile for a hydraulic gear apparatus, of the type bound to a support shaft (5) to form a driving or driven wheel of the hydraulic apparatus and comprising a plurality of teeth (6) extended with variable helix angle with continuous function in the longitudinal direction, wherein the teeth profile keeps a shape continuity in each cross section thereof. More particularly, each tooth of the toothed wheel is longitudinally split in three zones: initial (A), central (B) and terminal (C) zones, and the central zone (B) has a variable helix angle, while the initial (A) and terminal (c) zones have a constant helix angle. The invention allows to manufacture contra-rotating rotors, having a non-encapsulating profile and a helix shape such as to suppress the angular point at the center of the rotors themselves and therefore all the problems related to their machining.