GB586186A - Propeller hub for aircraft - Google Patents

Abstract

586,186. Propelling aircraft. AMBROSETTI, E., (trading as OFFICINE ETTORE AMBROSETTI). Sept. 23, 1943, No. 15628. Convention date, Oct. 1, 1942. [Classes 4 and 114] Two variable pitch coaxial propellers are driven in opposite directions, one of the propellers being directly driven by the engine shaft, or a shaft extending from a reduction gear, and the other being driven from the first propeller by gears mounted on a fixed tubular sleeve coaxial with the first-named shaft and carrying the members for effecting pitch adjustment. As shown, an extension 1 of an engine shaft 1a supports a propeller boss having tubular members 2 in which the roots 3 of the propeller blades can rotate. A similar propeller hub 7, 9 rotates upon a tubular sleeve 6 fixed to the engine casing and the two hubs are constrained to rotate in opposite directions by the bevel gear shown, the wheels 8 of which are mounted on a collar keyed to the sleeve 6 as shown in Fig. 3. The sleeve 6 is grooved to accommodate strips 4 extending from a collar 4a to a grooved ring engaging an eccentrically mounted pin 5 on the blade root 3. Similar strips extend from a collar 10a to a grooved ring engaging an eccentrically mounted pin 11 on the hub root 9. The collars 4a, 10a can be moved separately or independently to vary the pitch of the propellers. According to the Specification as open to inspection under Sect. 91 the eccentric pins 5, 11 may engage helical grooves in a member rotatable about the shaft 1. This matter does. not appear in the Specification as accepted.'