| 摘要 |
The invention relates to a method of venting a building such as a greenhouse, by means of a sheet member (1) which can be mounted in one or several openings of the building, as well as a sheet member for use in the method. The sheet member (1) comprises a frame with four sides (2, 3, 4, 5) wherein are provided at least two horizontal controls (7, 8), which are formed as first rack bars (9, 10). The frame has a horizontal edging (13) and several parallel slats (11) provided on at least one side hereof with a layer (14) made of windproof and elastic material. A pinion is mounted in rotatable position opposite each guide (7, 8) on the edging (13), said pinion comprising a first (19) and a second gear (20), the first gear (19) being in mesh with the mentioned first rack bars (9, 10), and the second (20) being in mesh with teeth (21) on a second rack bar (17) mounted in movable position on the edging (13). A movement by the second rack bar (17) in longitudinal direction will cause the second gear (20) and consequently the first gear (19) as well to rotate, whereby the edging (13) is caused to move upwards or downwards via the first rack bars (9, 10) depending upon the direction of movement of the second rack bar (17). Consequently, the layer (14) will either close off or clear an opening (32) to the effect that air may vent the interior of the building. |
