Patent ID: 8161728
Filing Date: 2012-04-24
Classification: F02K

Abstract:
1. A gas turbine comprising: a high pressure spool; a high pressure compressor; a high pressure turbine mechanically coupled to the high pressure spool; a lower pressure spool; a lower pressure turbine mechanically coupled to the low pressure spool; a fan having a first set of fan blades and a second set of fan blades, the second set of fan blades being located downstream of the first set of fan blades and being operative to rotate at a rotational speed corresponding to a rotational speed of the lower pressure spool; and a gear assembly mechanically coupled to the lower pressure spool and engaging the first set of fan blades such that rotation of the lower pressure spool rotates the first set of fan blades at a lower rotational speed than the rotational speed of the second set of fan blades and wherein the gear assembly comprises an epicyclic gear having a sun gear, multiple planet gears and a ring gear, the sun gear having an aperture; the sun gear is coupled to the lower pressure turbine; and the lower pressure spool passes through the aperture of the sun gear.