GB1258518A - - Google Patents

Abstract

1,258,518. Sighting devices for measuring angles. SYSTEM PAULIN A. B. Feb. 28, 1969, No. 10952/69. Heading G1F. An instrument for sighting on an object and for taking readings in azimith and elevation comprises a box-like casing 9 provided with a sighting groove 10 the casing 9 being rotatable in elevation about a pivot 8 carried by a horizontal pivot 7, the pivot 7 carrying an arm 13 with an index 12 co-operating with an elevation angle scale 11 marked on a transparent end wall of the casing 9, the pivot 7 being carried by a mounting 6 which is rotatable in azimith on a vertical main pivot 1, the stationary inner part of the pivot 1 having a graduated scale 5 which co-operates with an index 14 and vernier 15 on the mounting 6. The pivot 1 is secured to a ball- and-socket joint 2 on a tripod and a level 4 on the bearing enables its axis to be set vertical. The scale 5 is adjustably rotatable so that the zero of the scale may be orientated with respect to true north. When the sighting groove is aimed at an object azimith and elevation angles can then be read off from the scale, a vernier coding device for the scale 11 comprising sets of parallel vertical lines and lines inclined thereto joining one scale reading point to the next adjacent vertically spaced point. The casing 9 may be folded about the pivot 7 over the mounting 6 during transport of the instrument for protection of the scale 5 and its associated members, and the sighting groove 10 may be replaced, if desired, by a telescopic sight or by a sighting device which is extensible so that it has a greater length when the instrument is in use than when it is being stored or transported.