TRAWL NET LAYER-BY-LAYER COLLECTING DEVICE

摘要

Provided is a trawl net layer-by-layer collecting device for switching and opening/closing the net mouth of a trawl net lightly and autonomously. The trawl net layer-by-layer collecting device is constituted to comprise a frame (2) for drawing trawl nets (13a, 13b, 13c and 13d) vertically arranged and for mooring the net mouth edge of the upper net of the uppermost trawl net (13a) at its upper edge and the net mouth edge of the lower net of the lowermost trawl net (13d) at its lower edge, a pair of vertical bars (3) arranged on the two sides of the frame (2), sliders (12) slidably engaging at its two end portions with the vertical bars (3) for mooring the net mouth edges of the lower net of the upper trawl net and the upper net of the lower trawl net, net mouth opening/closing means (8) for retaining the sliders (12) at the upper end portions of the vertical bars (3) and for releasing the retentions of the sliders one by one, and control means (9). The control means (9) includes a timer, and a storage medium stored with the drawing time period, for which the net mouth opening/closing means (8) is activated. The control means (9) is constituted to input a net drawing water depth from a bathometer and a drawing time period from the timer, and to activate the net mouth opening/closing means (8) in accordance with the set activation water depth stored in the storage medium and in response to the arrival of the predetermined net drawing time period.