GB915164A - Improvements in or relating to map displays - Google Patents

Abstract

915,164. Radio-navigation. KELVIN & HUGHES Ltd. May 19, 1961 [May 26, 1960], No. 18649/60. Class 40 (7). [Also in Group XXXVIII] In a map display device for use in aircraft and comprising a map driven between a supply roll 1 and a take-up roll 2 by means of drive roller 4 operated by an M-type motor 30 in accordance with " along-the-track " Doppler radar signals from terminal 40, the map cooperating with an index 9 moved transversely thereof by an M-type motor 20 in accordance with "cross-track" Doppler signals from terminal 25, an edge of the map 14 (Fig. 2), is provided at predetermined positions with electrically-conducting areas 15 which, on passing contacts 13 positioned adjacent the edge, bridge the latter to complete the circuit of the motor 17 of a tape recorder 18 from which a pre-recorded message (e.g. instructions to the pilot) is reproduced. At the end of the message the tape recorder motor is switched-off either by means of conducting areas on the tape co-operating with switch members (similar to the above arrangement) or by means of a time-switch device. Instead of utilizing Doppler radar signals the map drive may be provided by the output selected by switch 33 of an M-type transmitter 34 driven by a constant speed motor 26 and the speed of such movement set by a manually-operated variable speed-control device 31. Also, by operation of a switch 24 (details of which are described with reference to Fig. 3, not shown) the output of a further M-type transmitter 28 may be employed for operation of the index 9. To enable maps having different scales to be employed, threespeed gear-boxes 22 and 36 controlled by a selector device 41 are utilized in the index and map drives respectively. Initial setting of the index 9 may be effected by means of a manual control 12. The map is illuminated by means of an A.C. energized electroluminescent panel 3.