GB666404A - Improvements in photographic cameras - Google Patents

Abstract

666,404. Range-finders. BOLSEY, J. Oct. 7, 1948 [Oct. 11, 1947; Oct. 5, 1948], Nos. 26215/48 and 26216/48. Classes 97 (i) and 98 (i). In a photographic camera which comprises a range-finder of the kind including a fixed mirror and a mirror which is rotatable with axial displacement of the lens for focusing, a helical slot in a member rotatable about the lens axis engages a pin which is secured to the lens mount and projects radially therefrom through a slot parallel to the lens axis and engages lever means on which the adjustable mirror is mounted, the arrangement being such that adjustment of the rotatable member effects simultaneously axial movement of the lens and rotation of the adjustable mirror. The range-finder in the camera shown comprises a plate 72 which is adjustably mounted in the body of the camera by pin and slot. connections 73, 74. Pivoted at 83 on the plate 72 is a lever 82, a lug 84 on which engages a pin 85. This pin is carried by the lens mount of the camera and projects through an axially extending slot in a fixed member and a helical slot in a member rotatable about the lens axis. Rotation of the latter member thus causes focusing movement of the camera lens and also rotates the lever 82. The end 86 of this lever contacts a lever 76, pivoted at 75 to the plate 72, spring urged at 81 and carrying a range-finder mirror 77, so that rotation of lever 82 causes adjustment of the range-finder mirror 77. The range-finder also includes a fixed mirror 89 carried by the plate 72 and the two mirrors lie opposite light entrance apertures in the camera front. The fixed mirror 89 may be partially transparent or may be fully " silvered " and of a size less than the aperture associated therewith so that the object can be seen directly through said aperture at the same time as it is viewed by reflection at the mirrors 77, 89. In order to compensate for camera lenses of different focal lengths, the levers 76, 82 may be slotted at 102, 108 respectively and each slot may have a conical tapping 103 or 109 engaged by a conical screw 104 or 110, whereby the levers may be bent. The rangefinder may be housed in a camera body as described in Specification 666,405 and this body may include film feed mechanism of the kind described in Specification 666,406.