GB884213A - Improvements in automatic lens covers for a binocular telescope - Google Patents

Abstract

884,213. Binoculars. D & D CO. Inc. Feb. 1, 1960 [Feb. 18, 1959], No. 3516/60. Class 97(1). A pair of binoculars comprises two housings for its lens systems which are slidably supported on a central bridge, protective lens covers being provided which are slidable in guides in the lens housings and mechanism for actuating the lens covers being located in the housings and in the central bridge so that movement of the housings on the bridge also moves the covers. In the embodiment shown in Fig. 1 the lenses cases 11, 12 are slidable on a bridge 10 which comprises four guides 40, two either end each of which comprises a plane part 43 and a toothed part 42 which engages a pinion 48 which is connected through a gear train 46, 55, 56 to a driving wheel, the teeth 59 of which engage the edge of a lens cover 21. The lens cover (Fig. 5) comprises slats 61, 62 of different lengths mounted in a web arranged so that teeth 29 engage the spaces between slats 61 and on rotation of wheel 58 draw the cover along a U-shaped guide rail 70. The two covers, for the eyepiece and objective respectively are separated in the open position by a plate 75 thereby preventing jamming. Louvre slats 61 have dimples 63 which position the cover on its rail and holds it away from other components of the lens casing. When the binoculars are opened by moving cases 11, 12 along bridge 10 teeth 42, 45 engage and cause the covers to be removed but when the minimum separation of the cases required for vision is reached the covers have been removed and the plane surface of pinion 48 slides on surface 43 of the guide to lock the covers in the open position. In the modification shown in Fig. 9 the covers each comprise two parts 121 (only one shown) each part is connected by a slot 149 therein to a pin 148 on a lever 135 pivoted at 137 said lever having a slot 144, 143 in which engages a pin 146 on the bridge 10. Part 144 of the slot is curved and part 143 is linear so that during the initial movement of cases 11, 12 along bridge 10 pin 146 moves in slot 144, rotates a lever 135 in direction of A and causes the lens cover to be moved along guide tracks away from the lens. When pin 146 slides in the now horizontal slot 143 no further movement of the lens cover is obtained.