GB796941A - Improvements relating to electrified trawls - Google Patents

Abstract

796,941. Trawl nets. GUDJOHNSEN, H., and GUDJOHNSEN, J. June 20, 1956 [July 2, 1955], No. 19153/56. Class 48. [Also in Groups XXXV and XXXVII] An electrified trawl comprises conductors 2 held in spaced relation by non-conducting transverse connections 3 and forming therewith a net of mesh size greater than the mesh size of the bag-shaped back part of the trawl, the conductors being connected by multi-core cables 9 to a current distributer 21 supplied by an A.C. generator 20 in such manner that the conductors in successive pairs receive alternating current impulses. The net formed by the conductors and the transverse connections 3 forms the mouth of the trawl. The current from the generator is fed by slip-ring brushes 22 to sliprings 23 and then through distributer brushes 24 to the lamellae of the distributer 21. The distributer brushes 24 and the slip-rings 23 are rotated by the generator through gears 25. The width of the distributer brushes 24 is less than or equal to the width of each lamella so that only two pairs of conductors are energized simultaneously and the gears 25 are arranged so that a full wave of current is supplied to each lamella at each contact with the brush. The position of the brushes 24 is arranged relative to the armature of the generator so that the current goes through its zero value when each brush contacts only one lamella. The distributer is mounted on the hollow rotatable axle of a drum 26 on which the multicore cables 9 are wound and the cables pass through the axle to the distributer. The cables serve also as towing hawsers. The generator is driven by a D.C. motor.