Apparatus for demonstrating the incidence of the sun's rays, for use with architects' plans

摘要

344,337. Solar ray demonstration apparatus. COOKE, TROUGHTON & SIMMS, Ltd., Buckingham Works, York, and CLAY, A. S., 16, St. James' Square, London. Sept. 3, 1929, No. 26798. [Class 106 (i).] An instrument for use on architects' plans to demonstrate the angle of the sun's rays at any hour of the day comprises a base, an hour circle representing the plane of the sun's path, and a pivotal member attached to the base and adapted to represent the sun's direction. In the form shown in Figs. 1 and 2 the semicircular arc B graduated in hours from sunrise to sunset is disposed upon a baseplate A at an angle dependent upon the latitude of the locality. At a point Cx representing the observer's position is secured a cord C to the other end of which is attached a ball C1 denoting the sun. The point Cx is selected so that the cord when set at noon makes an angle with the plane of the arc equal to the mean declination of the sun for the summer months. A similar but differently angled instrument may be used for the winter period. In a modification shown in Figs. 7 and 8 the arc B is a portion of a spherical surface and is graduated at both its edges for summer and winter use. In a further construction, Fig. 11, the arc is replaced by a graduated ring rotatably mounted in a horizontal annular plate A. The ring is graduated along both edges and may be variably set for latitude, both north and south.