Patent GB-130697-A (GB)
Title: Improvements in Gyroscopic Apparatus.
Inventor: GRAY JAMES GORDON
IPC: G01C21/18
Filed: 1918-03-18
Abstract: 130,697. Gray, J. G. March 18, 1918. Gyroscopic apparatus. - Relates to apparatus for defining and maintaining the true vertical, of the kind described in Specification 14032/15 in which a gyroscopic system composed of a gyroscope and a rotating erecting-device is attached to the vehicle by means of a gimbal frame and two pairs of pivots and stabilized into the vertical by the mutual action of the gyroscope and the erector. According to this invention, the erector consists of a member which rotates continuously in the direction of spin of the gyroscope, but at a much lower speed, carrying with it a set of masses which are caused to move on a track or rail, which track is stationary relatively to the casing of the gyroscope, the masses forming a symmetrical system when the track is horizontal. Fig. 5 illustrates the invention. Balls 12 are carried round by a rotating plate 11 on a fixed plate 8<1>; one example of the shape of the slots 13' containing the balls 12 in the plate 11 is shown in Fig. 7. By varying the speed of rotation of the member 11 of the erector, one may vary the rate of response to, and of recovery from, a disturbance such as that due to horizontal acceleration when the vehicle turns. The slots 13' are shaped as shown in Fig. 7 to make the rate of recovery slow from a small tilt, and rapid from a large tilt, centrifugal force confining the balls to the portions 13 of the slots when the tilt is small, and the 'balls moving the full length of the slot when the tilt is large; the rate of disturbance of such a device by accelerating-forces is small. In Fig. 13 is shown a construction in which symmetrically-disposed pusher-arms 3, 4 on the rotating spindle engage the rods of masses 9, 10 suspended from sleeved collars 5, 6, these masses moving ahead of the pusher-arms while travelling downhill when the device is inclined to the vertical, but being in contact with the pusher-arms while travelling uphill and thus applying the erecting-torque. The rate of recovery from a large tilt, or the rate of disturbance by an horizontal acceleration is made slow, and the rate of recovery from a small tilt is made quick, by such a construction as that shown in Figs. 14 and 15, in which there are two systems of rotating masses, the one system of balls 11 propelled by pusherarms 10 in the direction of spin of the gyroscope being operative when the tilt is small and there is no acceleration, the other system of balls 7 in slots 8 in a plate rotating in the opposite direction being inoperative when the tilt is small and there is no acceleration, but coming into action on the occurrence of a large tilt or of horizontal acceleration to give an opposite torque, the resultant effect being small or zero. Alternative methods of neutralizing the couple produced by the balls due to centrifugal force on the occurrence of horizontal acceleration comprise (1) a fan spinning in the opposite direction to the gyroscope about an axis parallel to the axis about which the balls rotate, so that a reaction couple is applied to the gyroscopic system in the direction of spin of the gyroscope, or (2) the attachment to the system of a fly-wheel with its axis horizontal and across the moving vehicle, so that the couple due to the azimuthal turning of the fly-wheel neutralizes the centrifugal couple, or (3) the attachment to the system of a fly-wheel with its axis horizontal and fore-and-aft with respect to the moving vehicle, so that the gyroscopic couple due to the azimuthal turning of the fly-wheel neutralizes the centrifugal couple. Normally, the apparatus is so constructed that the gyroscope axis is perpendicular to the plane of the erector, so that the axis of the gyroscope is vertical in the position of equilibrium; but the axis of the gyroscope may be fitted to make a small angle with the perpendicular to the plane of the erector, in which case the system will be in equilibrium when the erector plane is horizontal and the gyroscope axis is inclined to the vertical, the axis of spin then possessing an horizontal component which may be used to counteract couples due to centrifugal force.