| 摘要 |
Globe map (10) in which a light source (76) and a screen (46) cooperate to create on the wall of a shell (12) two hemispherical zones respectively lit and dark. Clockworks designed to rotate these zones around the center of the globe (10), according to the rhythm of the days and years, include a body (32), a polar day shaft (14) rigidly connected to the shell (12) and a year shaft (38) rigidly connected to the screen (46). The axes of the shafts (14 and 38) intersect at the center of the shell (12) along an angle equal to the angle of inclination of the plane of the equator on the ecliptic. Under nominal working conditions, the screen (46) rotates around the shaft (14) at the rate of one revolution per sidereal day and around the year shaft (38) at the rate of one revolution per tropical year. An optical device (84) integral with the screen (46) and whose axis coincides with that of the screen cooperates with the source (76), a transparent support (86) including a figure representative of the sun and a circular band (92) integral with the body (32) showing a calendar, for the projection of this figure and a band segment on the wall of the shell (12), so implementing a globe map clock.
|
