GB2470004A

GB2470004A - A gearbox unit for use with fish passes

Info

Publication number: GB2470004A
Application number: GB0907647A
Authority: GB
Inventors: Bruce Don
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-05-05
Filing date: 2009-05-05
Publication date: 2010-11-10
Also published as: GB0907647D0

Abstract

A gearbox of a fish or eel pass that can be attached to movable water penning devices and weirs. Changes in the weir's angle are transmitted from the downstream pass component (Figure D) via the gearbox to allow the upstream pass component G3 to deflect automatically. This deflection is intended to maintain a consistent downwards angle in the upstream water body to allow fish and eels to crawl or swim beyond the influence of the weir crest flow regardless of the weir's angle. The whole unit may be adjustable for height to suit water flow conditions by turning screws G7, G8 which move threaded blocks G9, G10 which are contained within housing G2 (Figure A).

Description

Gearbox for Eel/Fish Pass A self contained gearbox unit relating to the previously described eel (fish) pass (Patent Application Number 0808523.5, filing date 10.05.08.

The purpose of this gearbox arrangement is to transmit the effects of a change in weir angle, registered by the downstream end of the eel (fish) pass, to the upstream component, thereby ensuring that this component is always angled downwards into the upstream water body.

This will allow eels (fish) to ascend the pass to its apex and enable them to crawl (swim) beyond the influence of the weir crest flow.

The whole gearbox unit is able to be raised or lowered according to water flow conditions and the position or influence of the weir crest augmentation material.

An embodiment of the present invention will now be described by way of example and with reference to the accompanying drawings in which: Figure A is a view of the gearbox and associated components attached to the weir fixing bracket.

Figure B shows the same view as Figure A but with the gear housing cover removed.

Figure C shows a reversed view of the gearbox and associated components with the gear housing and shaft-end housing removed. It shows the remaining components attached to the weir fixing bracket.

Figure D shows the relationship of the gearbox to the rest of the eel (fish) pass.

Referring to the drawings there is shown an eel (fish) pass gearbox unit, GB1 that comprises gears, 01, seated in a gear housing, G2 with gear housing cover, G2a attached.

The downstream shaft, G3, is the attachment point for the downstream element of the eel (fish) pass. This shaft transmits movement from a tilting weir in relation to the downstream element of the eel (fish) pass to the appropriate gear. Because the gears are interlinked this movement is transferred to the upstream shaft, G4. The upstream element of the eel (fish) pass is attached to this shaft and deflects accordingly. The size and number of gears can be calculated to provide an approximately constant downwards angle in the upstream element of the eel (fish) pass, regardless of the tilting angle of the weir.

Both shafts 03 and (14 are supported on the non geared side by shaft-end housing 05.

The gears, Olin their housing 02, the shafts 03 and 04 and the shaft-end housing 05 are all able to be raised and lowered in relation to the weir fixing bracket, G6 by the rotation of the adjuster screws 07 and G8. Adjustment of 07 and 08 will allow either more or less water down the eel (fish) pass.

These adjuster screws pass through captive threaded blocks, G9 and 010 which are recessed into components G2 and 05. These adjuster screws terminate in the weir bracket, G6. The raising and lowering action is stabilized and supported by four guide pins, GIl, 012, 013 and G14. These guide pins are fixed into the weir bracket, 06.

Claims

Claims: 1. A gearbox which forms a component part of an eel or fish pass, that transmits the effects of any change in angle of the weir supporting the eel or fish pass, from the downstream element of the eel or fish pass to the upstream element of said pass.
2. A gearbox according to claim 1. in which the deflection of the weir, and hence the downstream element of the eel or fish pass, is transferred to the gearbox by means of attachment to a shaft.
3. A gearbox according to claim 2. in which the interlinked nature of the gears causes a second attached shaft to cause a deflection in the upstream element of the eel or fish pass.
4. A gearbox according to claims 2. and 3. in which the gearbox shafts are supported on the non-geared side by a shaft-end housing.
5. A gearbox according to claim 1. in which the gears are captive within an appropriately dimensioned gear housing.
6. A gearbox according to claim 5. in which the gears in their housing, the shafts and the shaft-end housings are all able to be raised and lowered in relation to the weir fixing bracket by the rotation of integral adjuster screws.
7. A gearbox according to claim 6. in which the action of the adjuster screws is stabilized and supported by multiple guide pins. *..*
8. A gearbox according to any of the preceding claims and substantially as herein described with reference to the accompanying drawings. * * *.** S... S.. S.... * . *S *S * * . * .