GB313221A - Improvements in course or route indicating apparatus for aerial or marine vessels - Google Patents

Abstract

313,221. Lochbihler, X. March 14, 1928. Route-progress indicators .-Indicating-apparatus for use on aircraft &c. comprises a pointer moved, at a speed proportional to that of the vehicle, over a rotatable table carrying a map and mounted within a fixed ring bearing compass graduations so that the table can be turned in accordance with the compass reading. The pointer 2 forms part of a rack 16 slidably mounted in a support 15 and driven by a worm 17 which is driven through reduction gearing from the engine 1 of the aircraft &c., the drive including a flexible shaft 21 and a clutch 19, 20. When the clutch is disengaged the pointer can be set manually by turning the handle 30. The pointer extends over the map 3 supported on the manually-rotatable table 3a which carries an index co-operating with a compass scale on the fixed ring 7. The support 15 for the pointer is pivoted on a cradle 32 which can be moved to any desired position around a ring 33 and secured by a clamp 31. If it is desired to travel, say, from a point M on the map, Fig. 3, to a point K, the map is first turned in accordance with the compass reading and the cradle is then moved round the ring 33 until, by turning the handle 30, the pointer 2 can be brought to the point M, the support 15 being turned within the cradle until the rack 16 is in alignment with the line MK and then clamped by a screw 31. The clutch 19, 20 is then engaged and thereafter the pointer will show at any instant the position of the vehicle along the desired route.