Spreading Device

Abstract

There is provided a spreading device (100) for trawl fishing and seismic survey operations. The device has an upper frame (111), an intermediate frame (113) and a lower frame (112). There are at least two upper panels (22, 23) between the upper and intermediate frames, and at least two lower panels (22, 23) between the intermediate and lower frames. One of the upper panels and one of the lower panels adjustable in its angle of attack with respect to other panels. There is provided a manual means for adjusting the angle of attack of the adjustable panels.

Claims

1-14. (canceled)

15. A spreading device for trawl fishing and seismic survey operations, the device comprising: an upper, an intermediate and a lower frame; at least two upper panels between the upper and intermediate frames; at least two lower panels between the intermediate and lower frames; one of the upper panels and one of the lower panels being adjustable in its angle of attack with respect to other panels; and manual means for adjusting the angle of attack of the adjustable panels in the form of: a set of apertures on a movable panel and a set of apertures on a fixed panel, differing pairs of the apertures being capable of alignment upon movement of the moveable panel.

16. A spreading device according to claim 15, wherein at least one of the panels is fixed.

17. A spreading device according to claim 15, wherein the adjustable panels are pivoted about their leading edge.

18. A spreading device according to claim 15, wherein the adjustable panels are pivoted about an intermediate axis positioned between respective frames.

19. A spreading device according to claim 15, wherein the adjustable panels are pivoted about their trailing edge.

20. A spreading device according to claim 17, wherein fixed members are provided close to the leading edges.

21. A spreading device according to claim 20, wherein the fixed members hydrodynamically shaped in the cross-section.

22. A spreading device according to claim 16, wherein the manual adjustment means is provided on at least one of the frames.

23. A spreading device according to claim 22, wherein the manual adjustment means is provided on a top face of the intermediate frame.

24. A spreading device according to claim 22, wherein the manual adjustment means is provided on a both the top and bottom face of the intermediate frame.

25. A spreading device according to any claim 24, wherein the apertures are adapted to receive a pin.

26. A spreading device according to claim 24, wherein the apertures are aligned opposite obliquely with respect to the local orientation of the adjustable panel.

27. A spreading device according to claim 24, wherein the apertures are arranged in the direction of adjustment.

Description

[0028] To help understanding of the invention, a specific embodiment thereof will now be described by way of example and with reference to the accompanying drawings, in which:

[0029] FIG. 1 is an aerial diagram of a fishing vessel towing a system of fishing gear;

[0030] FIG. 2 is an top cross-sectional diagram of the device showing the hydrofoils in an open position and the direction of the water flow through them;

[0031] FIG. 3 is a perspective diagram of the inner face of the spreading device;

[0032] FIG. 4 is a perspective diagram of the outer face of the spreading device;

[0033] FIG. 5 is a front diagram of the inner face of the upper frame of the spreading device;

[0034] FIG. 6 is a perspective diagram of the adjustment mechanism on the intermediate frame;

[0035] FIG. 7 is a top diagram of the adjustment mechanism on the intermediate frame; and

[0036] FIG. 8 is a side diagram of the spreading device.

[0037] Referring to the drawings, FIGS. 1 and 2 (FIGS. 1 and 13a respectively, as taken from our previous application EP 2734039 B1), show an aerial diagram of fishing vessel 50 towing a system of fishing gear comprising a pair of spreading devices 100 connected to the towing cables 51 and bridles 52 from the spreading device to the fishing trawl 53. The drawing shows the towing direction 4 of the fishing vessel and position of the fishing gear.

[0038] The spreading device 100 of FIG. 2 (13a) comprises a first panel or hydrofoil body 22, second panel or hydrofoil body 23 and third panel 24. The Figures show flow of water between the panels to spread the trawl.

[0039] The spreading device 100 of the invention has an upper frame 111 and a lower frame 112, separated by an intermediate frame 113. Between the upper and intermediate frame, there are three panels. The first two panels or hydrofoils 22, 23 are adjustable and have fixed leading edges 25, 26. These extend structurally between the frames, that is the leading edges 25, 26 welded to the upper frame 111 and the intermediate frame 113 and the intermediate frame 113 and the lower frame 110.

[0040] Third, after panels 24 fixedly interconnect the upper & intermediate and intermediate & lower frames respectively.

[0041] Both the upper and lower first and second fixed leading edges, 25, 26, are supportingly welded to each other by horizontal bars 21, with the second leading edge 26, being welded to the fixed third panel 24. These bars extend at both the front and rear faces of the spreading device 100 to act as a protection for the hydrofoil bodies.

[0042] The first and second hydrofoils 22, 23, have pivot round bar handles 35 extending between sockets (not shown) in the respective frames. The first and second hydrofoils have inner and outer panel plates 40, 41, which are curved to provide the panels with hydrodynamically induced lateral force.

[0043] For pivotal adjustment of the hydrofoils 22, 23, as shown FIG. 6, the intermediate frame 113 with apertures 20 on its top face, with the same number of apertures mirrored on the bottom face of the frame 114. The apertures are arranged in such a way so as to provide fine adjustments in the angle of attachment of the hydrofoils, namely between 0 and 12°, increasing in increments of 2°. That is to say, whilst they are arranged in front of their panels, each overlaps its neighbours in a direction away from its panel when pinned thereto, whilst successively deviating from the panel.

[0044] By adjusting the position of the first and second hydrofoils, 22, 23, the volume of water passing through the spreading device 100 is controlled, and as a result, so is the force exerted on the hydrofoils. This allows the device's position in the water to be altered, either vertically or horizontally.

[0045] A lug 7 is attached to the base of first and second upper hydrofoils by a bolt 4 that extends through it, passing through the chosen aperture in the intermediate frame 13 to hold the lug in place. A pin 6 passes through the head of the bolt 4 and subsequently through an aperture 5 in the side of the lug, thus restricting rotation of the bolt. A carabiner 30 passes through a slot in the end of the pin 6 to hold it in place.

[0046] The spreading device 100 has a slight inward facing curvature wherein the upper and lower frames extend in opposite directions from the intermediate frame 113.

[0047] There are a pair of apertured wings 37 extending inwards from the upper and lower faces of the intermediate frame 113. A threaded screw 40 extends through the apertures on both of the wings 37, to be secured in place by a nut 38 on the underside of the bottom wing. The screw 40 passes through four ears 36 on a plate 29, the plate itself having four separate apertures 31 onto which the towing cables will attach. The to ears 36 and the intermediate frame 113 being separably supported by individual hollow tubes 22. The plate can be rotated about the screw to adjust its radial position, thus altering the attachment position of the towing cables.

[0048] The outer face of the spreading device 100 is shown in FIG. 4, and includes an outer protruding rim on the upper, intermediate and lower frames, 111, 113 and 112 respectively, each of them having a number of apertures 60, 61 and 62 respectively, onto which the fishing trawl will directly connect.

[0049] The upper first and second hydrofoil bodies, 22 and 23 respectively, have a handle 35 each in order to aid the user to physically adjust the position of the hydrofoils.

[0050] The invention is not intended to be restricted to the details of the above described embodiment. Alternatively, the bolts 4 could be held in place using an alternative locking mechanism such as a linchpin or split pin that is directly attached to the bolt, rather than through a pin 6.

[0051] Furthermore, the bolts 4 could have a threaded end such that upon passing through the aperture, they can be locked in place with a nut.

[0052] It can be envisaged that any other suitable locking mechanism could be used instead of a bolt, pin and R-clip.