US Patent 11624323 Air turbine starter with primary and secondary air flow paths

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. A primary air flow path is defined between a primary inlet and a primary outlet. Air in the primary air flow path can flow into a secondary air flow path or rotate the turbine, that converts energy from the air flow to rotational mechanical energy. Air in the secondary air flow path can pass through at least a first cavity and first passage before rejoining the primary air flow or joining ambient air.