| 摘要 |
<p>The invention concerns a pelagic trawl door with variable hydrodynamic area. At its trailing edge (12) the trawl door is provided with movable plate elements (13, 14) that may be displaced in longitudinal direction of the trawl door. An opening (21) or a region at the trailing edge (12) can thereby be opened up or covered by a plate element (13, 14). The displacement can be effected by means of a screw spindle (22) which is operated manually or driven by an electric motor. By the invention is achieved a simple and light construction where a change in the area of the trawl door can occur such that a reduction in lateral force at the same time results in reduction of the towing resistance, thereby maintaining or enhancing the effect of the trawl door during fishery.</p> |
