Device for remotely controlling aircraft control surfaces
View Patent ↗A device for remotely controlling the control surfaces of an aircraft, the device comprising: an actuator member pivotable about an axis and entraining a rotary shaft; a stationary finger parallel to the shaft and supported at a radial distance from the shaft; a moving finger secured to the shaft and supported at a radial distance therefrom, both fingers being parallel to the shaft; a first slab supported at a radial distance from the shaft beside the two fingers on one side thereof and suitable for turning about the axis of the shaft; a second slab supported at a radial distance from the shaft beside the two fingers on their side opposite from the first slab, and suitable for turning about the axis of the shaft; a third slab supported at a radial distance from the shaft beside the second slab at an angular distance therefrom and suitable for turning about the axis of the shaft; a first spring between the first and second slabs; and a second spring between the first and third slabs.
1. A device for remotely controlling control surfaces of an aircraft, said device comprising an actuator member suitable for pivoting about one axis to drive a rotary shaft
comprising:
a stationary, first finger parallel to said shaft and supported at a radial distance from said shaft;
a second finger secured to said rotary shaft and parallel thereto and supported at a radial distance therefrom;
a first slab supported at a radial distance from said shaft and extending beside the two fingers on one side thereof and in such a manner as to be capable of turning about the axis of the shaft;
a second slab supported at a radial distance from said shaft and extending beside the two fingers on the side thereof opposite from the first slab and in such a manner as to be capable of turning about the axis of the shaft;
at least one third slab supported at a radial distance from said shaft and extending beside the second slab and at an angular distance (a) therefrom, and in such a manner as to be capable of turning about the axis of the shaft;
a first spring interposed between the first and second slabs; and
a second spring interposed between the first and third slabs;
whereby the device can occupy a plurality of functional positions, namely:
a neutral position occupied in the absence of any force being exerted on the actuator member, in which the moving finger is in alignment with the stationary finger, the first and second slabs are held pressed laterally against the two fingers in alignment and on either side thereof under the action of the first spring, and the third slab is held spaced apart from the second slab, the second spring not being prestressed;
a position pivoted in a first direction from the neutral position through a variable angle for which the moving, second finger is entrained relative to the stationary, first finger on the side of the second slab, thereby entraining it, and being subjected to the return force from the first spring interposed between said first and second slabs, and then pivoted still in the same direction through a variable angle with the second slab touching the third slab and thereby entraining it, and being subjected to the additional return force from the second spring; and
a position pivoted in a second direction opposite to the preceding direction, away from the neutral position through a variable angle in which the moving, second finger is entrained relative to the stationary, first finger on the side of the first slab, thereby entraining it, and being subjected to the return force of the first spring interposed between the first and second slabs, and then pivoted still in the same direction through a variable angle with the third slab touching the second slab and being subjected to the combined return forces of the first and second springs.
2. A device according to claim 1 , wherein both springs are torsion springs disposed coaxially about the shaft.
3. A device according to claim 2 , wherein both springs are helical springs.
4. A device according to claim 3 , wherein both springs are helical springs and wherein one of the two helical springs is inside the other.
5. A device according to claim 1 , wherein the first spring is made up of two springs in series, one of them being interposed between the stationary finger and the first slab, and the other one of them being interposed between the stationary finger and the second slab, and wherein the two springs in series have different respective stiffnesses, whereby an opposing force is different depending on a displacement direction of the actuator member.
6. A device according to claim 1 , wherein the actuator member is a manually-operable stick or knob.
7. A device according to claim 6 , wherein the actuator member is of the so-called mini-stick type.
8. A device according to claim 1 , further comprising motor-driven displacement means functionally associated with the stationary finger and suitable for modifying the position of the stationary finger.
9. A device according claim 1 , wherein the device is functionally associated with controlling pitch-control surfaces of the wing of the aircraft.