UNISON RING SELF-CENTRALIZERS AND METHOD OF CENTRALIZING

摘要

A centralizing assembly (60) for an engine (10) having a plurality or rotatable vanes (50) is provided including an engine casing (52) and at least one unison ring (54) disposed concentrically there about. A spacing gap (64) is formed between the unison ring (54) and the engine casing (52) and is variable between a maximum spacing gap (66) and a minimum spacing gap (70) in response to thermal expansion (68) of the engine casing (52). A centralizer element (62) includes a plunger element (72) movably mounted to unison ring (54) and spanning the spacing gap (64). At least one conical spring washer (76) is mounted to the plunger element (72) and exerts a centralizing force (74) through the plunger element (72) onto the engine casing (52). The at least one conical spring washer (76) maintains the centralizing force (74) between the maximum spacing gap (66) and the minimum spacing gap (70). Corresponding method (300) for centralising a unison ring (54) around an engine casing (52).