GB496216A - Improvements in or relating to magnetic compasses - Google Patents

Abstract

496,216. Magnetic compasses. KOLLSMAN, P. May 25, 1937, No. 14516. Convention date, May 25, 1936. [Class 97 (ii)] A magnetic compass comprises an elongated indicating element moved in azimuth by the directing magnets and also tiltable relatively to the casing, and a settable elongated reference member tiltable relatively to the casing and to the indicating element. The indicating element or needle G is attached to a float E pivoted about a point 32 and operated by a bar magnet 50. The needle G is read in conjunction with a settable reference member comprising two parallel arrows H, mounted on a member 61 connected to a central member 20 by gimbal joints 63, 65. The compass needle pivot 32 is carried on a post 30 slidable in the central member 20 and having a cushioning spring 27. The central member 20 is mounted in a liquid chamber B rotated as a whole to set the reference arrows H by a knob 70 connected by gearing to a pinion 78 fixed to the underside of the chamber. The setting is indicated by a scale 90 carried on the chamber and viewed through an aperture 92 in the rim of the casing M. The Specification as open to inspection under Sect. 91 comprises also reference to indicating instruments in general provided with the described indicating means. This subject-matter does not appear in the Specification as accepted.