Patent GB-282633-A (GB)
Title: A compensated gyroscopic device for the determination of planes or directions of reference
IPC: G01C19/44
Filed: 1927-10-20
Abstract: 282,633. Schneider et Cie, and Fieux, J. Dec. 22, 1926, [Convention date]. Gyroscopic apparatus.-Apparatus for use on an oscillating platform, sunh as a ship, for defining a plane of reference which is fixed relatively to the earth, comprises a freely mounted gyrocope and a compensating pendulum, these two members being suspended from the same center independently of each other and being connected together by a friction device. The friction device consists of a fixed member exerting pressure on the spherical surface of a rotary member, these two members being carried, one by the gyroscope and the other by the pendulum. Figs. 7 and 8 show one form of apparatus for defining a horizontal plane, in which the rotary member of the friction device is carried by the pendulum. The gyroscope rotates about a vertical axis within a casing 2 mounted on horizontal trunnions 4 on a ring 3 which is mounted on trunnions 6 in a ring 5. The ring 5 is mounted on trunnions 8 in a ring 7 which is mounted on trunnions 29 in a ring 28 rotatably mounted on a support 30. A frame 13 integral with the ring 5 carries a motor 42 and an electromagnet 41, this frame with attached parts constituting the pendulum. The motor 42 drives the concave spherical member 36 of the friction device in a direction opposite to that of the gyroscope, and also drives a wheel 44 which, together with the motor and its pinion 43, compensates the gyroscopic action of the member 36. The other member of the friction device is carried by the gyroscope and consists of a ball 19 on which bears a cylindrical mass 20. The spindle 37of the member 36 bears on the pivoted armature 38 of the electromagnet 41 which is normally excited to maintain the friction members in engagement, but can be de-energized, as for example during prolonged accelerations of the ship &c. so as to discontinue the action of the friction device. The gyroscope may also carry an arm 34 on which is a slidable weight 35, the suspension system being in this case rotated from the ship's compass &c. so that the arm 34 is in the meridian. The weight 35 is adjusted in accordance with the latitude so as to effect compensation for the rotation of the earth. When this device is used the pressure between the members 19, 36 can be substantially reduced. A platform 16, which in the form shown is horizontal, is carried by the casing 2 and remains fixed relatively to the earth's surface. Figs. 11 and 12 show a form of apparatus in which the plane 16 is maintained vertical and the rotary member 11 of the friction device is carried by the gyroscope. The gyroscope 1 having a horizontal axis of rotation is mounted in a casing 2 supported on horizontal trunnions 46 in a fork 45 having a spindle 47 which is freely mounted in the support 49. The pendulum 52, 53 is similarly mounted in a fork 50, the trunnions 46, 51 being coaxial. The mass 53 carries a support 54 for a flexible arm 55 terminating in a roller 56 bearing on the member 11. The casing 2 carries a rod 60 and weight 61 for the same purpose as the parts 34, 35, Fig. 7, and the spindle 47 carries a compass card 48. In this case the spindle 59 of the fork 50 is made to follow the card 48 or that of the ship's compass.