Improvements in Otter Boards for Trawl Nets.
Year: 1895

page_text: Date of Application, 21st June, 1895-Accepted. 27th July, 1895
Improvements in Otter Boards for Trawl Nets.
CARL AUGUST NIELSEN, of 133 Somerset Street, Hull, in the County of York,
Steam Trawler Captain, and HECTOR FOSTER FOURNY, of French Chambers,
Queen's Dock, Hull, Consulting Engineer and Marine Surveyor, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
Our invention relates to improvements in otter boards which are used to work
and spread trawl nets, as a substitute for the ordinary beam.
Now the object of our invention is to so construct the otter boards, that they
shall offer the least possible resistance to towing and spreading the net, and also to
raise the boards any suitable distance above the ground in order to avoid the
ploughing and shovelling of ground dirt into the net. By raising the boards a
suitable height above the ground, the ground dirt is enabled to pass under the
boards.
In carrying out our invention instead of constructing the boards with only a
plain iron shoe on the bottom, we attach to the boards two or more metal or iron
shoes, with or without wheels or rollers; the said shoes being arranged to swivel
on a spindle, bolt, or pivot, and so adjust themselves to the direct line of resistance,
no matter what angle the otter boards may be set when being towed. We ensure
the swivelling of the shoe by arranging that the pivot on which it works shall not
be fitted at the centre of gravity of the shoe. By this means we have greater
leverage at one end of the shoe than the other, and immediately pressure is applied,
the shoe swings round into the line of least resistance.
There are various ways of applying our invention. The shoes may be made
with one or more rollers at each end, with rollers at one end only, or with a single
roller. The shoes may also be made plain without rollers; in either case they
may be made of a solid block of metal, but preferably where it is required to raise
the otter board a considerable distance off the ground, the shoe can be made of the
open or box form, with or without wheels or rollers.
Our arrangement of shoes & rollers can be fitted to all descriptions of otter
boards at present in use, whereby considerable economy ensues.
To enable our invention to be fully understood, we describe the same by
reference to the accompanying drawings, in which :-
Figure 1, on Sheet 1, is a plan representing approximately the position otter
boards assume, when being towed and spreading a trawl net. a, a, represents the
corners of a trawl net, at which the ground rope, head line & wing rope end;
b, b, the bridles or warps.
c, c, represents the shoes and the position they assume
in direct line of resistance to towing.
Figure 2 represents an otter board in side elevation, with swivel shoes c, c,
attached. a represents shackles or attachment for the head line and ground rope
at any suitable height on the boards.
Figure 3 is an end elevation of Figure 2.
Figure 4 is a side elevation of a swivel shoe of the open or box type, with
wheels or rollers d, d, and working on a pivot at p. Intermediate rollers may also
be fitted.
Figure 5 is a side elevation of a swivel shoe of the solid type, with wheels or
rollers d, and pivoted at p. This may also be made of wood & iron.

page_text: Figure 6 is an end elevation of Figure 5.
Figure 7 is an elevation of shoe made with double wheels d, d.
Figure 8, Sheet 2, represents an otter board in side elevation with plain swivel
shoes c, c, without rollers. s represents shackles or attachment for the head line
and ground rope, at any suitable height on the boards.
Figure 9, is an end elevation of Figure 8.
Figure 10 is a side elevation of a plain solid swivel shoe, made in wood or iron.
Figure 11 is an end elevation of Figure 10.
Figure 12 is a side elevation of a plain swivel shoe of open or box type, shewing
chafing piece e attached.
Figure 13 is a side elevation of solid swivel shoe, shewing chafing piece fattached.
This may also be made of wood & iron.
Figure 14 is an end elevation of Figure 13.
Having now particularly described and ascertained the nature of our inven-
tion, and in what manner the same is to be performed, we hereby declare that
what we claim is :-
:-
1. In otter boards, attaching adjustable shoes, substantially as, and for the
purposes described.
2. Improved otter boards, providing for the raising of the boards to a suitable
height off the ground, in order to avoid ploughing up the ground and shovelling
dirt into the net, and to avoid useless waste of power, substantially as, and for the
purposes described.
3. Improved otter boards with shoes arranged to automatically adjust themselves
to the line of least resistance to towing, enabling trawling to be carried on with
more economy of power, substantially as and for the purposes described.
4. The combination of the parts constituting improved otter boards and gear, as
shewn and described.
Dated this 20th day of June 1895.
CARL AUGUST NIELSEN.
H. F. FOURNY.