GB2391787A - Worm bed with electric barrier - Google Patents

Abstract

The worm bed coprises an electric barrier 10 for preventing worms from escaping The barrier may comprise three parallel conductors 12 arranged a positive-negative-positive vertical configuration, and mounted on a non-conductive tape. The barrier 10 may be povided around the internal walls of the worm bed, just below the top of the walls. A controller 16 may be provided for regulating a supply of power to the barrier 10. In use, the electrified barrier 10 acts as an anti-crawl deterrent for worms.

Description

PO1823UK20030818CIonSpec 1 2391787 TITLE: Barrier The presentinvention

relates to abarrier,moreparticularly, but not exclusively, to abarrier for preventing migration of worms from a worm bed.

The use of worms for composts, fish food and other animal feed products is well known. To farm 5 and harvest worms for these purposes, worm husbandry, known also as vermiculture, generally takes place in a container referred to commonly as a worm bed. A typical worm bed consists of a rectangular vesselplacedin, on orraised above the ground, eitherindoors or outdoors, end which includes a volume of orgarucmaterialto which aparent stock of worms are introduced to produce a worm crop.

10 Worm beds canvaryinsize, depending on the scale end nature ofthe wormbreeder's enterprise (commercial ordomestic). Forinstance, asmallwormbed, used et the outset of a worm crop for example, will typicallybe Imwide, 2m long and 30cm deep. A large wormbed canbe in excess of 50 m long, 1.Sm wide and 50cm deep. Typically, a large worm bed will have a bed-life of 5 years and may be harvested at regular intervals.

15 Migration of worms from a worm bed is a common problem in vermiculture, which can have serious implications for the wonn breeder, inparticularifa substantialproportion ofthe parent stock is lost in the immediate period f allowing introduction to the worm bed, or ding vourable

weather conditions, for example.

Light is a known deterrent against worm migration. For indoor worm beds, it is common for 20 artificial lightingto tee provided at all times, to reduce migration ofthe worms from the worm teed.

However, this method of containment is not wholly effective in preventing worm migration, in partcularifthe supplyofpowerto the lithtingis interrupted, for example in apower cut. Furler, there can be considerable costs in providing continuous lighting for one or more worm beds.

P01 823UK 20030818 ConpledonSpec.wpd 2 To reduce the migration of worms from a worm bed, it is also known to provide a bamer, often referred to as an anti-crawl perimeter, around the upper end ofthe worm bed walls. A known barrierconsists of alayerofdamp-proofcoursewhichis provided between, and extends from, the upper two courses of a brick-built worm bed, to form a cantilever of approximately 1 Ocm about 5 the internal periphery of the worm bed, to hinder migration of worms from the worm bed.

However, such a barrier may not always be effective in retaining the worms in the worm bed.

It is an object ofthe invention to provide an improved barrier to reduce or substantially obviate the migration of worms from a worm bed or othercontainer. It is a furtherobjectofthe invention to provide a barrier which acts as an anti-crawl deterrent for worms and snails and the like.

10 Accordingto thepresentnvention, Here is provided a barrier foraworm bed or the like consisting of an electrifiable medium and acontroller for regulating the supplyofpowerto the electrifiable medium. Preferably, the electrifiable medimn comprises a plurality of conductors.

Conveniently, the plurality of conductors are mounted on or in a nonconductive tape.

1 5 Preferably, the electrifiable medium comprises an array of conductors arranged a positive-negative configuration. In a preferred embodiment, He electrifiable medium comprises an array of conductors arranged a positivenegative-positive configuration.

- The conductors are preferably arranged at a predetermined vertical spacing.

Theconlrollermayinclude amonitorcircuit,whichmonitosthe loading on the electrifiable medium.

20 The controllermayinclude amonitorcircuitwhichis configured to trigger an alarm if the voltage across the barrier is reduced.

P01823UlC20030818 CanpletionSpec.wpd 3 According to a further aspect of Me present invention, there is provided a worm bed or container having a barrier according to the broadest aspect ofthe invention, which extends around at least part of the internal periphery of the worm bedlcontainer.

Preferably, the barrier is mounted at or adjacent the upper end of the walls of the worm S bed/container.

The invention will now be described, by way of example only, with reference to the accompanying drawing, which shows a diagrammatic view of a barrier according to a preferred embodiment of the invention.

A barrier or anti-crawl deterrent is indicated generally at 10. The barrier includes an electrifiable 10 medium in the form of a rectangular array of conductors 12, a power source 14 and a controller 16. As can be seen, the array of conductors 12 consists of three conductors, arranged a positive-

negative-positive vertical configuration. In the preferred embodiment, the conductors 12 consist of bare copper wire strands mounted in me vertical configuration shown in Figure 1 on a non 15 conductive tape (riot illustrated). The conductors maybe of any suitable conductive material, for example aluminium, galvanised steel, stainless steel or tinned copper, and the tape may consist of any suitable non-conductive material, for example polyester or polyethylene.

The spacing of the conductors can vary from microns up to 10 inches, depending on the size and type of worm or snail or the like which the bamer 10 is intended to contain.

20 The power source 14 supplies power to the conductors 12, via We controller 16. The power source 14 provides a smooth DC supply to Me controller 16 between 9v and 24v. The controller 16 has a square wave output duty cycle of between 25% and 75%. In the preferred embodiment, the duty cycle is set at50%,which gives en average controller output of approximatelyhalfofthe

P01823UK20030818ConpichonSpec.wpd 4 input voltage from the power source 14. The controller output is set at 15Hz and has amaxirnum output current of 50mA, which is regulated to 11.5mA in the preferred embodiment. Alternatively, the controller output can be varied between 5Hz and 20Hz.

The non-conductive tape is mounted about the internal periphery of a worm bed, not illustrated, 5 adjacent the upper end ofthe walls ofthe worm bed. Below the level ofthe conductors 12, the worm bed contains a volume of organic bedding material and a stock of worms for breeding and harvesting. In this embodiment, the worm bed consists of a brick-built rectangular tank including a lined concrete base, with the tape mounted at a distance of 10 cm above the level of the bedding material. 10 Traditionally, the worm stock of a wortn bed is prone to migration, particularly in periods of darkness, i.e. the worms crawl from the bedding material up the internal walls ofthe worm bed and escape. In the worm bed ofthe preferred embodiment, it has been observed that aproportion of He worms which crawlup theinternal walls ofthewormbed are deterred from crawling on to thebarrier 10, 15 it is believed at leastpartlybythe magnetic field generatedbythebarrier 10. Hence, the invention

provides an anti-crawl deterrent for the worm stock in the worm bed.

However, if aworm continues, undeterred, up an internal wall ofthe worm bed and on to the tape, the worm will eventually come into simultaneous contact win a positive and a negative conductor 12. At this point, current flows through theworrn's body and/or over the mucus coaling on the 20 wortn's body, causing the wonn to have a muscular contraction and to drop offthe wall, back into the organic material. Hence, the invention provides an effective containment system forreducing the migration of a worm stock from a worm bed. The effect of the current on the wonns is not sufficient to cause substantial harm to the wonns, even upon contact with the conductors 12.

The controller 16 and power source 14 ofthepreferred embodiment canpowerapproximately 25 200m of conducting material.

PO 1 823UK 20030818 ConpkoonSpec.wpd 5 The controller 16 includes a monitor circuit, which monitors the loading on the conductors 12 and the supply ofpowerto the controller, inuse. If the conductors 12 become overloaded, for example due to an amount of bedding material coming into contact with the conductors 12 during filling, the voltage is reduced. If the voltage is reduced to along, ineffective voltage atwhich the barrier 10 5 is unable to deterworms from approaching the conductors 12 ortopreventworrnsirompassing over the conductors 12, for example at avoltageofapproximately2.5V, the monitor circuit triggers an audible, and/or visual alarm, to signal that the barrier 10 requires maintenance.

The controller includes an internal back-up battery. In the event that there is an interruption in the supply of power to either the controller 16 or the worm bed, the monitor circuit detects the 10 interruption in power supply and the controller 16 switches to operate from the internal back-up battery for approximately 21 days or until the mains supply is restored.

Further, the controller 16 includes an auxiliary correction for controlling an interface relay, whereby the controller 16 is connectable in electrical corornunication with the emergency lighting system for an indoorwormbed, for example. In the evens that there is apowercut, the monitor circuit detects 15 the interruptioninpowersupply andactivates the emergency lighting vie the interface relay, whilst simultaneously switching the controller 16 to operate from the internal back-up battery, as described above.

In a modified embodiment ofthe invention, the bamer consists oftwo conductors arranged in a positive-negative vertical configuration, which are mounted on anon-conducting surface around at 20 least a portion of the internal periphery of a container for breeding worms.

The conductors maybemounted directlytoewaLlsofthewormbed/container and at anyheight above the bedding material.

The present invention is suitable for all forms of worm bed/container and the like, to provide an anti-crawl deterrent.

Claims (12)

P01 823U}C 20030818 CanpletionSpec.wpd 6 Claims

1. A barrier for a wonn bed or the like consisting of an electrifiable medium and a controller for regulating the supply of power to the electrifiable medium.

2. A barrier as claimed in claim 1, in which the electrifiable medium comprises a plurality 5 of conductors.

3. A barrier as claimed in claim 2, in which the plurality of conductors are mounted on or in a non-conductive tape.

4. A barrier as claimed in claim 2 or 3, in which the electrifiable medium comprises an array of conductors arranged a positive-negative configuration.

I 0

5. A barrier as claimed in any one of claims 2 to 4, in which the electrifiable medium comprises an array of conductors arranged a positivenegative-positive configuration.

6. A barrier as claimed in any one of claims 2 to 5, in which the conductors are arranged at a predetermined vertical spacing.

7. A barrier as claimed in any preceding clann, in which the controller includes a monitor 15 circuit, which monitors the loading on the electrifiable medium.

8. A barrier as claimed in any preceding claim, in which the controller includes a monitor circuit which is configured to trigger an alarm if the voltage across the barrier is reduced.

9. A worm bed or container having a barrier as claimed in any preceding claim in which the barrier extends around at least part of the internal periphery of the worm bed or 20 container.

PO 1 823UIC 200308 1 8 ConplfflimlSpec.wpd 7

10. A worm bed or container as claimed in claim 9, in which in the barrier is mounted at or adjacent Me upper end of the walls of We worm bed/container.

11. A barrier substantially as hereinbefore described and shown in Figure 1.

12. A wortn bed or container substantially as hereinbefore described and shown in Figure 5 1.