Device for shifting a propeller into reverse, comprising an actuator acting on a crank pin

Abstract

The invention relates to a device for controlling the shifting of a propeller turbine engine into reverse mode, by acting on a shaft (13) for controlling the pitch of the propellers. The device comprises: at least one centrifugal weight (14) arranged to drive the propellers into the flag position thereof under the action of the centrifugal force; and an actuator (9) that can rotate the control shaft (13) in order to shift the pitch of the propellers from a traction mode to a reverse mode, passing through a zero pitch position. The invention is characterised in that the centrifugal weight (14) is in an unstable equilibrium position in relation to the action of the centrifugal force when the control shaft shifts the pitch of the propellers (6) through the zero pitch position. In addition, the invention comprises an actuation means (19) that exerts a torque on the control shaft (13) when the centrifugal weight is in the unstable equilibrium position, so as to prevent it from staying in this position.

Description

technical field [0001] The present invention relates to the field of aeronautical turbine engines, and in particular to the field of turbine engines or high-speed propeller engines with unducted propellers known as "open rotors", and the field of devices for controlling the direction of the blades of such propellers. Background technique [0002] Aviation engine technology is developing very fast, and one of the aspects being studied is to improve the fuel consumption rate of civil aircraft engines, and this aspect currently refers to the development of open rotor engines. This engine, as described in the applicant's company patent application FR2941493, comprises a conventional turbine engine gas generator, one or more of which turbine stages drive an unducted fan extending outside the engine. Considering the desired thrust level and the reduction of blade noise, the engine is usually equipped with two coaxial counter-rotating unducted propellers, that is to say, the two pr...

AI Technical Summary

Problems solved by technology

If this is not the case, if the propeller is always at the zero pitch setting, the opening of the throttle will cause the engine to fly, causing the risk of overspeed and consequently breaking the blade, or, if the pitch setting is kept in the positive pitch setting range , can even cause the propellers to apply traction even though the pilot is expecting these propellers to have a braking effect

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