Thrust force-compensating apparatus with improved hydraulic

Abstract

An axial thrust force-compensating apparatus is provided in a gas turbine engine having relatively rotatable first and second structures. The axial thrust force-compensating apparatus includes a first annular part mounted to the first engine structure and having an annular end surface, a second annular part mounted to the second engine structure and having an annular end surface which opposes and faces toward the end surface of the first annular part, and a primary hydraulic pressure balance mechanism for providing separate outer and inner fluid flows to the respective outer and inner regions between the end surfaces at pressures responsive to the amount of separation existing between the end surfaces at those regions. The separate fluid flows at the pressures produce a film of fluid flowing between and in contact with the respective end surfaces which generates primary compensating moment forces acting on the end surfaces to maintain the end surfaces in generally parallel relationship. The improved apparatus also has a secondary hydraulic pressure balance mechanism for producing secondary compensating moment forces which complement the primary compensating moment forces produced by the primary pressure balance mechanisms to limit the magnitude of any non-parallel relationship between the end surfaces of the first and second parts.