Patent GB-944828-A (GB)
Title: Improvements relating to gyro-vertical apparatus
Inventor: BARNES JEFFERY WALTON
IPC: G01C19/52
Filed: 1961-10-14
Abstract: 944,828. Gyroscopic apparatus. FERRANTI Ltd. Oct. 11,1962 [Oct.14, 1961], No.36933/61. Heading G1C. A gyrovertical has a hermetically sealed housing 1, Fig. 1, filled with air or other gas so that the same air or gas is circulated through the erection device. The rotor 2 is electrically driven within a casing 5 mounted in gimbal 9, the rotor 2 having vanes 10 which act as a centrifugal pump supplying air from inlets 11 in casing 5 to two pairs of jets 12, 13 and 14, 15, Fig. 2, symmetrically placed around the spin axis and discharging in a direction parallel to the spin axis of rotor 2. A first set of shutters comprising four single knife-edge shutters 16, 17, 18, 19 mounted on a spider 20 pivoted about an axis 21 parallel to, but offset from, the spin axis, co-operate with the jets 12-15 to provide erection about the pitch axis, the spider 20 being weighted at 24. During normal operation the weight 24 will only deflect as far as to abut spring 26 or 27, this corresponding to tilts of up to 7 degrees, but during tilts greater than this and during acceleration the weight 24 contacts stop 28 or 29 so that all of the jets 12-15 are opened and the erection is inoperative about the pitch axis. A second set of shutters 33-36, Fig. 3, pivoted about an axis 38 parallel to, but offset from, the rotor spin axis co-operate with jets 12-15 to provide erection about the roll axis the shutters being carried by a spider 37 weighted at 39. A similar arrangement of springs 41, 42 and stops 43, 44 are provided but the double knifeedge shutters 33, 34 ensure that when the weight 39 moves against stops 43 or 44, due to deviation of the spin axis by more than 7 degrees from the vertical or during acceleration which occurs during turns, the pitch and roll erection is controlled by the pitch tilt, the sense of the roll erection being reversed in relation to pitch tilt by the direction of the turn i.e. a pitch-bank erection system is used. If pitch-bank erection is not required the jets 12, 13 may be positioned on the pitch axis and jets 14, 15 on the roll axis instead of being at 45 degrees thereto. The single leaf springs 26, 27, 41,42 may be replaced by double leaf springs in which the two leaves rub against each other when the springs are deflected to damp the movement of the weight. Alternatively damping may be provided by wire cantilever springs rubbing on the sides of guide slots. To render the casing 5 pendulous when the gyrovertical is not in use, two balls may be provided, each held by a magnet at the bottom of a vertical tube on the casing 5, the balls being forced upwardly to a neutral equilibrium position by air bled from jets 12,13 when the rotor 2 is running at operational speed. The balls may be replaced by pistons or weighted bellows expanded by air pressure and electrical contacts thereon may indicate that the full rotor speed has been reached. When a solenoid 30 is energized, a peg 31 is moved into holes 32, 45 in spiders 20, 37, so that weights 24, 39, are only free to move into abutment with springs 26, 27, 41,42, so that restoring torques are exerted on the rotor 2 for all angles of tilt.