Tunnel-type greenhouse aeration system - comprises framework of transverse arches with elevatable covering

摘要

The greenhouse consists of a framework comprising of a number of arches, which are in three parts. Two lateral curved parts are anchored in the ground and connected at their upper ends by a third curved part. The arches are connected longitudinally by two lines of spacers located on either side of the upper section of the arch and which are so shaped that they present a gull-wing profile with the lowest point midway between two arches. The covering is in three longitudinal strips; one covering the top section of the arch between the two spacers and overlapping the two other strips corresponding to the side sections of the arch. Aeration is achieved by a method of opening a gap between the upper and side strips of the cover.