A gyroscope in which the rotor is supported with respect to its driving shaft by a plurality of intermediate gimbals in which each intermediate gimbal is torsionally attached to the rotor and to the driving shaft, the attachments being positioned, the spring constants being adjusted, and the moments of inertia of the gimbals being adjusted to allow the rotor to be a free rotor while eliminating rectification torques, caused by oscillatory inputs on the shaft, from the rotor.
A dynamically tuned, free rotor gyro is provided with three concentric gimbals. The principal moments of inertia of the gimbals are selected to completely cancel the errors of twice spin frequency rectification effects by merely adjusting the inertias of the gimbals.
4297904 - Gimbals - Owned by British Aerospace Public Limited Company (London,GB2)
A gimbal assembly for carrying a gyroscope rotor for spin about a z axis is described which has an inner boss (3), and outer ring (6), first and second gimbal frames (4 and 5) situated between the two, first outer pivots (8) pivoting the first frame (4) to the outer ring (6) about a y axis, second outer pivots (10) pivoting the second frame (5) to the outer ring (6) about an x axis, first inner pivots (11) pivoting the second frame (5) to the boss (3), and second inner pivots (9) pivoting the first frame to the boss (3) about the x axis, the gimbal frames (4 and 5) being interlaced one with another. A preferred method of forming the inner boss (3), the outer ring (6), and the gimbal frames (4 and 5) from a billet of solid material is also described.
A dynamically tuned gyroscope having a single gimbal has torsion flexures with torsional stiffnesses such that, at its tuned speed, the gyroscope is insensitive to angular vibration at a frequency of twice the rotor rotational speed. The drive shaft is connected to a first torsion flexure having an effective torsional stiffness K.sub.1 of zero, K.sub.1 being made zero by the use of ball races or pivots, by known mechanical methods such as over-center or toggle spring action, or by the use of magnetic or electrostatic systems. The rotor is connected to a second torsion flexure which is orthogonal to the first flexure. The second torsion flexure has a torsional stiffness K.sub.2 equal to 4w.sup.2 r.sub.3.sup.2 m.sub.3 where w is the tuned rotor speed, m.sub.3 is the component mass of a gimbal, on which the torsion flexures are mounted, on an axis through the center of gravity of the gimbal and normal to the plane of the gimbal, and r.sub.3 is the distance of the component mass m.sub.3 from the center of gravity of the gimbal.
A gimbal (108) on the driving side and a gimbal (106) on the rotor side and a gimbal arrangement with two gimbals (22,76) are formed by two coaxial, cylindrical rings (10,64) wherein peripheral cuts (12,14,16,18 and 66,68,70,72, respectively), having ends forming angles are provided in the rings. The peripheral cuts separate the portions of the gimbals (108,106) from the gimbals (22,76). The ends form leaf springs (for example 60 and 100), which form flexural pivots. One leaf spring (60) is connected to the gimbal (108) on the driving side and the other leaf spring is connected to the gimbal (106) on the driven side. The cuts are produced by electroerosion.
A ring element on the driving side and a ring element on the rotor side and a gimbal arrangement with two gimbals are formed by two coaxial, cylindrical rings, wherein peripheral cuts, having deflected ends are provided in the rings. The peripheral cuts separate the portions of the ring elements from the gimbals. The ends form leaf springs which form flexural pivots. One leaf spring is connected to the ring element on the driving side and the other leaf spring is connected to the ring element on the driven side. The cuts are produced by electroerosion. Each of the cuts is symmetrical with respect one of two planes extending at right angles to each other.
