| 摘要 |
<p>A device for covering areas such as gardens, terraces, etc. consists of an assembly of rectangular plates, arranged above the zone to be covered, the narrow sides of which are pivot hinged to parallel upper cross members of a frame. The plates can be pivotted simultaneously by means such as chains or cables running on wheels and moved by a crank handle. The device may be driven if required by an electric motor controlled by a monitor responding to humidity and/or rain by switching on the motor which is disconnected when the plates reach the limit. The plates are pref. of transparent matl. such as acrylic glass or GRP. The structure has all the advantages of fixed shelters without the disadvantages of movable arrangements, such as the relatively rapid determination of textile fabrics and the limited dimensions of marquees, etc. Cleaning also is much easier.</p> |
