Improvements in apparatus or mechanism for operating lights or ventilators or the like of horticultural houses, buildings, and the like

摘要

256,442. Roberts, A. Nov. 7, 1925. Valve apparatus, actuating. - Ventilator opening and closing mechanism for greenhouses &c. of the kind in which two rods sliding in opposite directions are connected by levers &c. to the pivoted sashes, is provided with levers 6 pivoted to the frame at 7 to links 8 attached to the window and to the sliding rods, the respective pivots 7. 12, 10 being at the apices of a triangle. The connections between the links 8 and the sashes and levers 6 are ball-and-socket joints as shown in Fig. 4, a ball 14 mounted between hemispherical side checks 15 on a pin secured to the links 8 engaging an eye secured to the sash 1. The levers 6 are pivoted to split sockets bolted on the two rods 3. The levers 6 are bent upwardly and downwardly respectively at their ends to bring the thrust on the links 8 into the same plane.