A device for lateral sheering of a towed object, particularly adapted for opening a trawl net

摘要

572,253. Fishing. WOLLASTON, H. J. BUCHANAN-. Jan. 15, 1944, Nos. 816, 1421, 3443 and 5094. [Class 48] An otter-board, shown in plan, comprises a flat plate (metal or wood) 1, and a curved, tunnel-like, s t e e r i n g device 3 which lies above, or below, the plate 1, to cause the board to ride to right or left of the towing ship which is connected to the board by a rope attached to one of a number of holes placed near the inner edge 4. The board is weighted so that it rides with the device 3 up or down, as desired. The nose 2 of the board may be curved. Skates, or wheels, may be fitted to ride on or cut into the sea bottom. A rope attached to the trawl, or other towed object, is connected to the plate 1 by a fitting passing through one of a number of holes positioned at the rear end of the edge 4. The outer edge B of the plate 1 is bent up to give rigidity to the plate. Relative dimensions and angles of the parts forming the board, are given in the Specification. The nose may be bent oppositely to the steering device so that the board slides on the water surface. The attached weight may be in the form of a metal cover or sheath near the nose, or a rod or tube hinged to the plate 1. The tow rope may be attached to the plate at more than one place, the attachments including chains. The skates, or wheels, when fitted, are inclined away from the boards so that the lower parts tend to dig into the sea bed during towing on the bottom. Strengthening bars and plates may be fitted to the boards. Brackets from the baseplate 1 may support the steering device. When fishing on ground where obstructions may be met, a weak link in the warp to the trawl is designed to give way under heavy stress and allow the otter board to be hauled out tail first.