GB760251A - Gyroscopic apparatus - Google Patents

Abstract

760,251. Electric indicator systems. SPERRY CORPORATION. Jan. 5, 1954, No. 314/54. Class 40 (1). [Also in Group XX] Gyroscopic apparatus mounted in an aircraft for indicating the vertical and horizontal is compensated for errors introduced by linear and centrifugal acceleration by applying a tilt to the gyroscope in accordance with the horizontal speed of the craft and the rotor speed. As shown, Fig. 1, the gyroscope, mounted in a casing 1 with its rotor rotating about a vertical axis, is pivoted on horizontal axis 3 in gimbal 2, itself mounted on horizontal axis 4 in gimbal 5, which is journalled on a horizontal axis 6. A vertical follow-up ring 8 is also journalled in gimbal 5 about axis 4. Roll movement of the craft on which the gyroscope is mounted produces a signal from inductive tranducer 23 by relative movement between an armature 24 attached to the casing 1 and coils mounted on the ring 8, which is fed to amplifier 22 causing motor 19 to drive the fore-and-aft trunnion 6<SP>1</SP> to reposition gimbal 5. Pitch movement of the craft produces a signal from pick-off 34 by relative movement between the horizontal ring 2 and vertical ring 8, which is fed to amplifier 26, causing motor 21 to drive the trunnion 4<SP>1</SP> to reposition ring 8. A pendulum 9 pivoted at 10 on an extension 11 of the ring 8 has a pin 13 engaging in a slot in the casing 1 so that the tilting of the ring 8 causes the pendulum 9 to bring the gyroscope back to the vertical. Roll movement of the gyroscope is similarly corrected by a pendulum 14 attached to ring 8, acting through the forked arm 16 and pin 18 on ring 2. It is stated that to correct for errors introduced by linear and centrifugal accelerations the gyroscope must be tilted at an angle dependent on the horizontal speed of the craft. Hence a true speed signal obtained at meter 31 is fed to a potentiometer 33<SP>1</SP>, and multiplied by a factor depending on the angle of climb or dive obtained by a resolver 27 to give the horizontal speed of the craft, and this signal is subtracted from that received from pick-off 34 to actuate the pitch follow-up motor 21, whereby the ring 8 is maintained vertical, but the gyroscope 1 is processed to an inclined position to correct for accelerations. The apparatus contains visual indicators 40, 41, 42 to indicate pitch, and 43, 44 to indicate roll. Specification 637,993, [Group XX], is referred to.