Improvements in course setters for magnetic compasses

摘要

612,584. Magnetic compasses. BENDIX AVIATION CORPORATION. May 28, 1946, No. 16255. Convention date, July 2, 1945. [Class 97 (ii)] A magnetic compass is provided with a secondary course-setting compass card which is adjusted by means comprising a lever passing through the wall of the housing with freedom to rock relatively thereto. The main compass card 12, Fig. 2, pivoted at 14 is provided with magnets 9 and may be read against a lubber line through window 18. The secondary card 22 is mounted on pivot 24, and may be adjusted to indicate course-setting by gearing 34, 36 actuated by a lever 26 provided with a ball and socket mounting 28 in a support 30, The upper end 46 of lever 26 is secured in a cap 44 which engages the plane cam surfaces 52, 54 of a collar 56 having teeth driven by a worm drive from shaft 64 rotated by knob 66. Rocking of head 44 by rotation of knob 66 causes the ends of lever 26 to describe circles around the axis 58 so that the lower end 31 rotates pinion 34 and the secondary card 22. A flexible metal bellows 68 is soldered or brazed to block 30 and secured to end 46 of lever 26 to render the mechanism liquid-tight. The head 44 may be sleeved to the lever 46 and the head 44 and collar 56 rotate as a single unit.