Insect-proof seal for green house roof - has rack and pinion transmission and flexible gauze cover

摘要

Seal prevents entry e.g. of lice and dust in a greenhouse Unit may be wall or roof-mounted in an air frame. Seal unit is used in conjunction with so-called lice protection gauze (1) protecting the greenhouse plants. Movement of air frame is obtained by utilising e.g. a motor-driven rack and pinion (3). Unit includes a rigid tube (4) and aperture (6) for entry of the rack. Aperture is enclosed by diaphragm (7). Lubricant supply (8) in bottom of tube (4) serves the operating spindle (2).