GB2422297A

GB2422297A - Weir cleaning apparatus

Info

Publication number: GB2422297A
Application number: GB0601431A
Authority: GB
Inventors: Martin Frewer
Original assignee: JILL FREWER
Current assignee: JILL FREWER
Priority date: 2005-01-24
Filing date: 2006-01-24
Publication date: 2006-07-26
Anticipated expiration: 2026-01-24
Also published as: GB0601431D0; GB0501494D0; GB2422297B

Abstract

Apparatus for cleaning a weir or dam comprises a plurality of cleaning modules adapted to be placed astride the crest of the weir and moved along the crest (12, fig 1). The modules each comprises abrasive weir cleaning elements 21 which, in use, contact and scour the surface of the weir (10, fig 1) as the apparatus is pulled along the weir. Each cleaning module preferably comprises first and second plates 17, 20 hingeably connected together by hinge 19 for opening and closing movement about the hinge axis.

Description

Weir Cleaning Apparatus This invention relates to apparatus for the

cleaning of weirs in order to remove algae, weeds and the like.

Weirs are artificial dams or barriers constructed across watercourses in order to regulate flow or to raise the water level upstream of the weir. In most instances, weirs are formed from concrete, although other materials including synthetic plastics materials may be used, and have an upstream face formed to slope at a relatively steep angle and a downstream lace formed to slope at a relatively shallow angle and over which, in use, water flows to the lower level. Conventionally, when viewed either from upstream or downstream, weirs have a "flat V" configuration, according to which the weir comprises portions which extend from each respective bank at a shallow, downwardly-sloping angle, meeting in the central region of the river and, thus, forming a "flat V". Such a configuration enables control to be exercised even during periods of low flowrate when the water level is low, in that water will still flow over the weir at the central region, even if it is restrained at the higher, outer regions.

Especially where a weir is critical in the sense of controlling or maintaining tiow at a sensitive location, having regard to considerations such as flood prevention and water abstraction, the growth of weeds and algae on the weir and especially towards the crest thereof not only alters the ability of the weir to control the flowrate in the intended manner but also has an affect on flow calculations based on the properties of the weir, resulting in inaccurate control. It is, therefore, desirable for weirs, especially critical weirs, to be maintained clear of weeds and algae and, indeed, of any other obstructions. To this end, it is conventional to clean weirs manually by employing divers but such cleaning can generally be carried out only during periods of low flowrates; such cleaning is therefore not only labour-intensive and expensive but cannot be carried out sufficiently regularly to maintain the weir free of obstruction for much of the time. In fact, such cleaning is generally carried out only on an annual basis.

It is an object of the present invention to provide weir cleaning apparatus which can be used at any time of the year and enables weir crests to be cleaned safely without the need for divers or other operatives to enter the watercourse.

In one aspect, the present invention provides apparatus for cleaning weirs, the apparatus comprising a plurality of cleaning modules adapted to be placed astride the crest of a weir and to be moved along said crest, the modules each comprising abrasive weir-cleaning elements which are in contact with and scour the weir as the modules travel along the weir in use.

In one embodiment, each module comprises first and second plates, which may be rectangular in shape, hingeably connected together for opening and closing movement about a hinge axis parallel with adjoining or juxtaposed edges of the plates and, in use, disposed along and above the crest of the weir, whereby the plates are disposed respectively against the upstream and downstream faces of the weir, at least one of the plates carrying abrasive weir-cleaning material on its inner- or weir-facing surface. By "opening and closing movement" is meant that the plates can move so that their facing surfaces are juxtaposed or touching (closed) or are angularly spaced or spread apart (open).

Each cleaning module may be joined to its adjacent module or modules by pivotable or articulated links, or the modules as a group may be joined together at their hinged edges by means of a flexible link member, whereby adjacent pairs of modules are permitted to become angularily displaced from each other on being moved across the weir and in particular in moving between respective side portions of the weir, where they meet to define the lower point of the flat V. Bushes may be provided between respective or adjacent modules to provide separation therebetween, to prevent them from interference or obstruction as between adjacent modules, which otherwise would inhibit such angular displacement movement or would attenuate the cleaning effect of the abrasive material in preventing proper contact between a given plate and the weir. Conveniently, such bushes are 1.ormed from rubber or other suitable resilient material.

Optionally, the first andlor second plates include panels which, in use, can be deployed to extend below the plate to extend its reach over the appropriate weir surface. Optionally, the panels also carry abrasive weircleaning elements or material. When deployed against the upstream face of the weir, the effect would be to increase the water pressure against the upstream side of the module, to enhance stability on the weir and also to enhance the cleaning effectiveness. On the downstream side, which generally has a shallower angle of slope and, hence, a longer reach than the upstream face, the effect of the panels, especially if carrying abrasive material, is to increase the cleaning area below the crest of the weir.

The panels may be slidably attached to the host plates and secured at a desired position, either fully retracted or extended to a desired amount, by suitable clamp means.

Optionally, the outer-facing surfaces of the plates include means for receiving and holding ballast material to increase the weight of the plate and, hence, enhance the stability of the module when deployed in use on the crest of a weir.

Movement of the cleaning modules along the weir may be effected either by exerting from the bank a pulling force on a suitable rope or cable or by applying a pulling or pushing force via a control arm or pole attached through a suitable articulated connection to one of the modules in the group. Preferably, such a pole is pivotably attached to a connecting link about a pivot axis orthogonal to the hinge axis of the plates, to allow the pole to be pivoted from one end to the other of the modules, the link being itself pivotably attached to the module about a pivot axis parallel to or coincident with the hinge axis of the plates, to allow pivoting movement either backwards or forwards relative to the module. In a preferred arrangement, a cleaning module includes a connection member extending upwardly in use from the upper, hinged, parts of the plates and providing multiple attachment locations for the control arm, in order to improve stability especially when withdrawing or removing the module or an array of modules. The connection member may comprise a rigid arch attached to the upper hinge elements, the central part of the arch being formed with or carrying a plurality of attachment means for a control arm.

In another aspect, the invention provides a cleaning module for use with one or more other such modules in apparatus for cleaning weirs as hereinbefore described, the module comprising abrasive weir-cleaning elements adapted to be placed astride the crest of the weir to he in contact with and scour the weir faces as the modules travel along the weir in use.

Cleaning modules according to the invention are preferably formed from mild or stainless steel sufficiently thick to provide stability when disposed about the crest of a weir. The abrasive material may comprise tufts or bristles of a stiff polymeric material such as polypropylene or brass wire especially for cleaning concrete weirs; the material may he mounted to or secured in a suitable subframe which itself is removably retained in place on the inner-facing surfaces of the plates. The modules may be provided, at or adjacent the hinge connection of the plates, with rings or eyelets for attachment of a pulling rope or cable, or the module (or at least one module in a group therefore) may be provided with means for connection of a pulling/pushing pole.

In yet another aspect, the invention provides a method of cleaning weirs, the method comprising deploying on the crest of a weir a Plurality of cleaning modules as hereinbefore described and causing the modules to travel along the weir with the abrasive weir-cleaning elements in scouring contact relationship with the weir.

Optionally, the method may be carried out by using a single module, especially when moved along the weir from the bank with the aid of a pole.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, of which: Figure 1 shows an array of cleaning modules disposed along the crest of a weir; Figure 2 shows the modules of Figuie I with panels extended; Figure 3 is a side view of the modules of Figure 2; Figure 4 is a front view of a module according to the invention, adapted for movement with a pole; and Figure 5 shows a front view of another module with an alternative attachment for the pole.

With reference firstly to Figure 1, the upstream face (10) of a weir is defined by the riverbed (11) and the crest (12) of the weir. The crest is in the form of a shallow or flat "V", having a low point (12A). Disposed along the crest (12) is an array of cleaning modules (13) joined together by a cable (14) equipped with eyelets (15) for attachment of a pulling rope or cable (not shown), adjacent pairs of modules in the array being separated by rubber bushes (16). The modules (13) consist essentially of upstream (as shown) plates (17) each carrying on its outer surface a panel (18) adapted for sliding deployment, as shown in Figure 2, to extend below the plate (17) in the direction shown by the arrows, in order to increase the water pressure exerted on the upstream-facing plates against the surface of the weir. As shown in Figure 1, the bushes (16) allow the modules to be respectively angularly displaced to angle 2, to maintain contact between the plates and the weir surface, as the modules traverse the weir from one limb of the V to the other limb.

Turning now to Figure 3, it is seen that the plates (17) are connected at their upper edges by a hinge (19) to another plate (20) which, in use, lies against the downstream surface of the weir (not shown). The hinge connection (19) enables the plate to be deployed with the angle subtended between plates (17) and (20) corresponding with the angle between the respective weir faces and, of course, the plates can be folded together, with their inner-facing surfaces juxtaposed or touching, for transportation and storage purposes. As shown in Figure 3, the innerfacing surface of the upstream plate (17) has abrasive weir-cleaning elements (21) attached thereto. Such elements may comprise tufts or bristles of suitable filamentary material or, alternatively, may comprise an abrasive open-cell plastics foam. The abrasive material may be itself mounted on or attached to a suitable frame which can be removably attached to the inner-facing surface of plate (17), whereby the frame can be removed either to replace one form of abrasive material with another or for cleaning purposes.

With reference now to Figure 4, a module similar to those shown in Figures 1 to 3 and including plate (17), panel (18) and hinge (19), is adapted for movement along the crest of a weir by means of a pole operated from a bank. The end (22) of the pole remote from the operative is received in socket (23) which is connected by hinge (24) to spigot (25) which itself is attached to a tubular part (26) which can rotate with respect to the hinge (19), so that the spigot (25) can be rotated to deploy the pole either in front of or behind the weir, as well as (by virtue of pivot 24) from one side to the other.

Although, with reference to Figure 3, the module is shown with abrasive material applied only to the inner-facing surface of the upstream plate (17), such material could also be applied to the inner-facing surface of downstream plate (20), according to the immediate

field requirements at the time.

With reference to Figure 5, the plates of the cleaning module (30) have an upper hinge (31) and a rigid arch (32) is fixed to the outer hinge elements so as to bridge over the top of the module in an upstanding disposition. The arch includes a series of apertures (33) for selective attachment of the end of a control arm or pole, or pulling rope or cable, to improve stability in moving the module across a weir. A tubular part (34) is attached to the central hinge element for providing an alternative engagement means for the control arm or pole, similar to part (26) of Figure 4.

Claims

Claims 1. Apparatus for cleaning weirs, the apparatus comprising a

plurality of cleaning modules adapted to be placed astride the crest of a weir and to be moved along said crest, the modules each comprising abrasive weir- cleaning elements which are in contact with and scour the weir as the modules travel along the weir in use.
2. Apparatus according to claim 1, in which each module comprises first and second plates hingeably connected together for opening and closing movement about a hinge axis parallel with adjoining or juxtaposed edges of the plates, at least one of the plates carrying abrasive weir-cleaning material on its inner- or weir-facing surface.
3. Apparatus according to claim I or claim 2, in which each cleaning module is joined to its adjacent module or modules by a pivotable or a flexible link member.
4. Apparatus according to any preceding claim, including bushes between respective or adjacent modules to provide separation therebetween.
5. Apparatus according to any preceding claim, in which the first and/or second plates include panels which, in use, are deployable to extend below the plate to extend its reach.
6. Apparatus according to any preceding claim, in which the outer-facing surfaces of the plates include means for receiving and holding ballast material.
7. Apparatus according to any preceding claim, including means for attachment to a pulling means to one of said modules.
8. Apparatus according to claim 7, in which the attachment means comprises a connecting member pivotably attached to the module about a pivot axis parallel to or coincident with the hinge axis of the plates.
9. Apparatus according to claim 7, in which the attachment means comprises a connection member extending upwardly in use from the hinged parts of the plates and providing multiple attachment locations for a control arm, rope or cable.
10. A cleaning module for use with one or more other such modules in apparatus according to any preceding claim, the module comprising abrasive weir-cleaning elements adapted to be placed astride the crest of the weir to be in contact with and scour at least one weir face as the modules travel along the weir in use.
11. A method of cleaning weirs, the method comprising deploying on the crest of a weir one or a plurality of cleaning modules as claimed in claim 10 and causing the module or modules to travel along the weir with the abrasive weir-cleaning elements in scouring contact relationship with at least one face of the weir.