Patent ID: 9207642
Filing Date: 2015-12-08
Classification: G04B

Abstract:
1. A timepiece including a dial, a timepiece movement and means of indicating the sunrise and sunset taking account of seasonal variations, said means including a sphere reproducing the terrestrial globe, a shell arranged concentrically to the sphere and arranged to demarcate a portion of the terrestrial globe where it is night from another portion where it is day by indicating the position of the earth's terminator, the sphere being arranged to be driven by the movement so as to rotate at a rate of one revolution per 24 hours about a first axis of rotation corresponding to the polar axis of the terrestrial globe, and the shell being mounted to pivot about a second axis perpendicular to the first axis and intersecting the first axis substantially at the centre of the globe, wherein the first axis of rotation is oriented parallel to the plane of the dial and the second axis perpendicularly to the plane of the dial, wherein the sunrise and sunset indicating means also include an annual cam arranged to be driven in rotation by the movement at the rate of one revolution per year, and a cam follower arranged to cooperate with the cam, the cam having a profile representative of the tilt of the sun relative to the equatorial plane, and a kinematic connection so that the plane subtended by the earth's terminator forms, with the polar axis, an angle equal to the angle of tilt of the sun relative to the equatorial plane; and wherein the timepiece included a calendar mechanism arranged to indicate the date and the month, and wherein the annual cam is kinematically connected to the calendar mechanism.