Patent ID: 11932405
Assignee: ROLLS-ROYCE PLC
Field: Transport (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 0:
1. An aircraft cabin blower system comprising:
a cabin blower compressor having a contactless bearing arrangement;
a transmission having: a transmission output arranged to drive the cabin blower compressor; a first transmission input arranged to receive mechanical power from a gas turbine engine; and a second transmission input;
a reversible variator arranged to receive power from the gas turbine engine and to output mechanical power from a variator output to the second transmission input, the reversible variator operable to output in both forward and reverse directions of rotation; and
a controller configured to control a speed of the variator output and a direction of rotation of the variator output,
wherein:
a speed of the transmission output is a function of a speed of the first transmission input, a speed of the second transmission input and the direction of rotation of the variator output, the second transmission input increasing the speed of the transmission output when the variator output rotates in the forward direction and reducing the speed of the transmission output when the variator output rotates in the reverse direction; and
the controller is configured so that, during a start-up process of the cabin blower system, the variator output is controlled to rotate in the reverse direction until a start-up threshold condition is satisfied and then reversed to rotate in the forward direction.