GB617055A - Improvements relating to instruments for use on moving craft - Google Patents

Abstract

617,055. Gyroscopic apparatus. SPERRY GYROSCOPE CO., Ltd., MURTAGH, H., and TAYLOR, J. A. May 28, 1942, No. 7250. [Class 97 (iii)] In a gyrovertical comprising a frame or rotor case carrying one or more stabilising rotors, the stabilized rotor case or frame is carried in a first gimbal frame which is itself carried in a second gimbal frame and means are provided for controlling at least one of the gimbal frames so that in all manoeuvres three degrees of freedom are retained. As shown in Fig. 1, an air-driven rotor 14 spins within a case 13 supported by a gimbal ring 10 and forked frame 7 rotatable respectively about axes C, C<1>, B, B' and A, A<1>, and all free to turn through 360 degrees. The rotor case is erected by pendulous U-shaped shutters 33, 331 and 39, 39<1>, Fig. 3, pivoted on the upper part of the rotor case and variably intercepting air jets issuing through orifices 30, 31<1> and 31, 31<1> provided in the floor of the rotor case. The forked frame 7 is rendered pendulous by a weight or as shown, by two mercury receptacles 41, 42, so as to urge the axes B, B<1> towards the horizontal and prevent the axis from coming into line with the spin axis, e.g. during 90 degree banks. The axle of the rotor case 13 carries at opposite ends a disc 47 or 48, Fig. 2, simulating the " nose " of an aeroplane and also carries two vertical pointers 49, 491 and 50, 501. The gimbal ring 10 carries part-spherical screens 43, 44 to serve as backgrounds for the indicators. A ring 51 surrounding the window 2 carries a strip 52, Fig. 9, simulating an aeroplane and also carries bank angle graduations 54. The indications of the altitude of the craft are provided by the relation between whichever of the discs 47 or 48 and its associated pointer is visible in the window 2. For example, a half-loop followed by a half-turn brings the rear disc 48 and the indicator 50, 50<1> to the front immediately behind the window. In Fig. 9 the dial shows level flight, whilst in Fig. 12 a combination of a climb and a right bank is shown, the " nose " 47 having moved up and the aeroplane figure 52 having banked to the right, the indications of this and other evolutions being correct in general direction as observed through the window. When, owing to a vertical dive the pointers 49, 49<1> and 50, 50<1> are no longer visible in the window additional pointers 55, 56, Fig. 2, carried by the rotor case come into view. An indication of the false vertical, for comparison with the approximately true vertical given by the pointers 49, 491 and 50, 50<1> is provided by pointers 60, 61 carried by the forked frame 7. The pointer 61 may be read against a scale of degrees 62, Fig. 12, and may be used as a correct-bank or side-slip indicator by noting its departure from the zero graduation. Specification 393,695 is referred to.