US 6,257,528 B1 · Vehicle control system and method employing control surface and geared tab

Abstract

Control systems and methods for a vehicle such as an aircraft or watercraft employ a trailing edge control surface that is pivotal about a pivot axis fixed relative to the vehicle and is deflected to create control forces, and a tab pivotally mounted to an aft end of the control surface. An aft end of a linkage is connected to the tab spaced from the tab pivot axis, and the linkage extends forward to a forward end that is coupled to fixed vehicle structure, such that deflection of the control surface causes a deflection of the tab as long as the forward end of the linkage does not lie in line with the control surface pivot axis, the in-line position defining a neutral position of the linkage. A gearing control actuator is coupled to the linkage and is operable to position the forward end of the linkage at selectively variable distances on one or the other side of the neutral position, thus providing variable gearing ratios between the control surface and the tab. Tab gearing ratio can be varied as a function of vehicle operating condition. An alternative control system includes a backup tab actuator for providing tab deflection upon failure of the actuator system that deflects the control surface. The tab can be used as a control tab for providing the motive force for moving the control surface, or the tab can be used as a mini control surface by locking the control surface in a fixed position.

Claims15

Dependent claims

A control system for a vehicle having a trailing edge control surface mounted for pivotal movement about a control surface pivot axis fixed relative to the vehicle, and a control surface actuator connected between the vehicle and the control surface and operable to pivotally move the control surface, the control system comprising:

a tab connected to the control surface so as to be pivotable about a tab pivot axis located aft of the control surface pivot axis;
a linkage having an aft end connected to the tab and extending forward therefrom to a forward end of the linkage, the forward end of the linkage being movable along a path so as to permit the forward end to be selectively placed in various positions including a neutral position in which the forward end is in line with the control surface pivot axis and other positions in which the forward end is displaced from the control surface pivot axis;
and
a gearing-control actuator connected to the linkage and operable to move the linkage so as to cause the forward end thereof to move along said path, the gearing-control actuator being further operable to position the forward end of the linkage at selectively variable distances on at least one side of the neutral position so as to vary an effective gearing ratio between the control surface and the tab.

1 more element

a tab connected to the control surface so as to be pivotable about a tab pivot axis located aft of the control surface pivot axis;
a backup tab actuator coupled to the tab for pivotally moving the tab during a failure of the control surface actuator;
and
a tab controller operatively connected to the backup tab actuator, the tab controller being operable to enable functioning of the backup tab actuator upon detection of a failure of the control surface actuator.

1 more element

Dependencies are inferred from the claim text.

Vehicle control system and method employing control surface and geared tab

Life of this patent

Vehicle control system and method employing control surface and geared tab

Life of this patent

Abstract

Claims15