Patent GB-125087-A (GB)
Title: New or Improved Range Finder or Telemeter.
Inventor: ANDERSEN FRIDTJOV
IPC: G01C3/10
Filed: 1916-03-01
Abstract: 125,087. Andersen, F. March 2, 1915, [Convention date]. Sights and methods of sighting.-Consists in providing range-finders of the depression type, adapted to adjust automatically the gun control system described in Specification 10275/12, and calculated to allow for curvature of the earth, with means for correcting for tide-level and refraction. A telescope 1 pivoted at 2 is provided with an arm 4 ending in a roller 5 engaging the periphery of a cam 6, the circumference of which is shaped to give ranges, and is calculated for the earth's curvature and normal refraction. A worm wheel 8 fixed to the cam 6 engages a worm 9 which is slidably connected with a screwed shaft 14 turned by a hand wheel 10 and by another hand wheel 13 for finer adjustment. A nut 15 carried by the screw 14 is provided with a pin 16 engaging the point of intersection of the control bars of the gun control system, and the nut carries a microscope (not shown) adapted to travel along a scale 18. The correction for tide-level is made by means of a gear wheel 19 on the shaft 14 engaging another gear wheel 20 secured to a screw 21 which carries a nut 22 provided with studs 23 engaged by the slotted forked end 24 of a lever 25, the other end 27 of which is also forked and slotted to engage studs 34 on a sleeve 35 rotating on the shaft 14, but secured against axial displacement by shoulders 36, 37. The slotted end 27 also engages studs 29 on projections 30 of a nut 31 carried by a screw 32 and vertically adjusted by a hand wheel 33. When the screw 14 is turned, the nut 22 moves along the screw 21 and by manually setting the nut 31 the relative position of the studs 34, 29 is varied so that the fulcra 29 may be adjusted to give the required extent of axial movement to the shaft 14 carrying the nut 15 and pin 16, in either direction, or to give no movement when the studs 34, 29 are axially alined. To correct for refraction, the head of the screw 32 is journaled in a member 38, the upper part 41 of which carries a slotted pivoted piece 43 through which passes a rod 44 curved in either direction, one end of which is revolubly mounted in a slotted forked member 45 engaging studs 46 on the nut 22, and the other end of which is provided with a worm wheel 49 operated by a hand wheel 51. As the nut 22 moves along the screw 21, the rod 44 raises or depresses the part 41 carrying the screw 32 and nut 31, so altering the position of the studs 29. The inclination of the rod 44 is adjusted by the hand wheel 51, and when the centre line of the rod is horizontal the rod will be inoperative. The apparatus is suspended from a fixed frame 52 by means of a pivot 60 supported by an adjustable centre bearing 62. A spring 61 resting on ball bearings 63 is housed in an adjustable nut 66 carried by the frame 52, and the upper end of the spring presses against a flange 60<a> fixed loose on the pin 60 and bearing against ball bearings 64, carried by a nut 65 on the pin 60. The apparatus is rotated in azimuth by means of a hand-wheel 59 with gearing engaging a worm wheel 53 fixed on the franco 52.