AU765688B2 - A chlorinator - Google Patents

Description

1 A CHLORINATOR FIELD OF INVENTION This invention relates to electrolytic cells (herein after termed chlorinators) for the production of sanitising agents from dissolved salts such as chloride and/or bromide salts.

The invention has application, in particular, but not exclusively to use in swimming pools and spas.

PRIOR ART o*oo Swimming pool chlorinators usually include a titanium anode with a platinum group or other catalytic coating and a titanium cathode. The platinum group coating on the anode is a comparatively expensive component of the chlorinator. These electrodes are generally fixed in position in the chlorinator housing. The chlorinator described in Australian patent 512425 15 has an anode and cathode fixed within the chlorinator housing.

The electrodes comprise anode and cathode rods which are positioned alternately about an annular housing. There has also been developed a chlorinator with a removable cap having four flat cathode plates and a casing with fixed flat anode plates. When the cap is attached to the casing, the cathode plates are supported by casing guides in positioning and maintaining them in the housing in an alternating arrangement with the anode plates. The removable cap also includes electronic circuitry, diagnostic display panel, and electrical connections to the anode and to the power supply.

All chlorinators suffer from the build up of deposits particularly calcium carbonate on the cathode during use. The deposits lower the efficiency of the electrolytic reaction.

There have been a number of methods used to remove the calcium carbonate deposits from the cathode. One method involves reversing the polarity of the electrodes to remove the deposits. For example the Australian patent 512425 describes reversing the polarity to remove calcium carbonate deposits from the cathode in the chlorinator. The use of this method, however, shortens the life of the relatively expensive coating on the anode.

Treating the cathode with a weak acidic solution has also been used to remove calcium carbonate deposits. However this procedure is potentially dangerous to the operator and can damage the anode coating.

S 15 Calcium carbonate deposits have also been scraped off the cathode surface but during the scraping, the coating on the anode can be damaged. As well the method has limited success for fixed electrode assemblies because the close proximity of the electrodes to one another restricts access to some of the calcium carbonate deposits on the cathode thereby preventing their complete removal.

Calcium carbonate deposits have also been hosed off with pressurised water. For the same reasons as the scraping method, this method also has limited success.

An alternative method used to clean the cathode involves drying the calcium carbonate deposits by placing the entire electrode assembly in the sun and then gently tapping the electrode assembly to shake off the dried deposits. However, the time it takes to dry and remove the deposits represents downtime that the pump and filter cannot be used allowing algae and other microorganisms to grow and make the pool unsuitable for swimming.

SUMMARY OF THE INVENTION Thus it is an object of the present invention to provide a chlorinator with a removable cathode which can be easily cleaned and reassembled thereby overcoming at least in part one or more of the above mentioned disadvantages associated with cleaning of the prior art chlorinators.

In accordance with the present invention there is disclosed an electrolytic chlorinator device comprising an elongate body having a base and a top, said base being adapted for releasable water tight connection to a pipe to form a T-junction therewith with said body being substantially upright, and said top being releasably engaged with said body in a water tight arrangement, said chlorinator further comprising an elongate anode which is mounted within said body and •oo aligned therewith and an elongate cathode which is mounted to said top, extends into the interior of said body, and is juxtaposed with said anode wherein said cathode is removable from said body interior for cleaning by releasing said top from said body and moving said top to withdraw said cathode from said body.

The chlorinator is preferably a venture or flow diverter type which treats water diverted by venturi from the direct flow path.

toO• •The housing may be of any suitable shape depending on the type of chlorinator. In one form the chlorinator is a venturi 2972A type chlorinator with a tubular housing.

The mounting preferably provides a cap for the housing.

The cap is preferably adapted to engage the housing by any suitable means that is able to form a seal, but preferably the cap is attachable to the housing by complementary screw thread means. In an alternative form the cap may be attachable with the use of a bayonet type fitting.

The cathode may be attached or attachable to the cap.

Where the cathode is detachably attached to the cap, the 10 cathode may be replaced without replacing the cap. However the cap and cathode is replaced where the cathode is fixed to the cap. The cathode may be of any suitable shape. It is preferred that the cathode shape is such that it complements the anode in using a maximum surface area of the anode during 15 the electrolytic reaction. The cathode may be a single plate, multiple plates or a tube. Preferably the cathode has any suitable tubular shape including tubes with a square, triangular, or circular cross-section. In one preferred form the cathode is cylindrical having an outer surface opposing an inner surface of the anode. In one embodiment where the cathode is a tube in a venturi type chlorinator, there may be provided an extension tube engagable with the tubular cathode whereby the extension tube extends into the direct water flow path thereby establishing venturi flow through the housing.

The cathode is mountable within the housing so that the cathode may be removed and inserted without interference or restriction.

The cathode may also have one or more spacers attachable to the electrode to prevent the cathode electrode from damaging the anode during removal or positioning. The spacers may be in the form of projecting protrusions extending laterally from the cathode or a ring surrounding the cathode. Alternatively, the anode or an inner surface of the housing may have suitable spacers to prevent the cathode from damaging the anode.

The electrical connection to the cathode may take any suitable form. For example the electrical connection may comprise a conductor from the cathode passing through the 10 mounting to present a terminal on the outer surface thereof.

The cathode assembly preferably has an electrical connection means including a disconnectable electrical terminal connectable to a power supply. Suitable electrical terminals include socket connectors, pinned plugs, and screw-down 15 electrical connectors.

The anode is preferably attached to the housing. An electrical terminal for the anode is preferably attached to any suitable position in the housing. The anode may be electrically connected in a similar fashion as the cathode terminal.

It is desirable to be able to detect the presence of hydrogen gas in the chlorinator so that it may be vented to avoid creating a dangerous situation. It is also desirable to be able to determine whether air is trapped in the chlorinator.

Therefore it is preferable that the chlorinator includes a gas sensor electrode that is able to detect a voltage potential difference when it is immersed in the water compared to when it is out of the water. Therefore, it is preferable that a gas sensor electrode is located within the chlorinator in the position where it will be exposed to any buildup of gas. The chlorinator may also include a gas sensor electrode within the housing. The gas sensor electrode is suitably electrically connected to a sensing terminal.

Preferably both the gas sensor and sensor terminal are attached to the cap. Alternatively, the gas sensor electrode may be attached to an inner surface of the housing.

Cathodes are prone to buckling under mechanical and electromechanical loads imposed by service. It is also desirable to have cathodes that do not buckle with use thereby making it difficult to reposition them within the housing relative to the anode.

The cathode may be any shape that does not buckle with use.

For example the cathode may be a tubular member. The tubular member may be any suitable shape including square, circular, or triangular in cross section. Alternatively the cathode may be a corrugated plate or mesh.

20 The cathode may be extended by the engagement of a tube into the direct flow path thereby establishing venturi flow through housing.

BRIEF DESCRIPTION OF THE DRAWINGS In order that this invention may be more readily understood reference will now be made to the accompanying drawings, which illustrate a preferred embodiment of the invention and wherein: FIG 1. is a side elevation of the assembled chlorinator of the 30 current invention; FIG 2. is an exploded perspective view of the chlorinator of FIG 1.; FIG 3. is a partial sectional view of the assembled chlorinator; and 2972A FIG 4. is a view of the disassembly of the chlorinator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the figures, there is shown a chlorinator having a housing 11, anode 12 and cathode 13.

The chlorinator 10 is a venturi type chlorinator for 2972A 8 mounting in an upright position and connection to a T-piece pipe. The housing 11 is cylindrical in shape with a clear cylindrical wall so that an operator can determine whether water is flowing through the chlorinator, detect the possible build up of gas, and whether calcium carbonate has deposited on the cathode.

The anode 12 is a platinum group coated titanium mesh electrode. The anode 12 is cylindrical in shape and is positioned within the housing 11 so that an outer surface of the anode 12 is adjacent an inner surface of the housing 11.

The anode 12 is maintained in position by the fixing of an .0 anode contact 14 with resin to the housing wall lla. The anode contact 14 is electrically connected to the anode *terminal socket 15, which is connectable to an electrical power 15 supply. The housing 11 has threaded ends 16, 17 for attachment to a collar 18 and the T-piece pipe respectively. At each end 16, 17 there are fitted O-rings 20 for forming a water tight seal.

The cathode electrode 13 includes a cylindrical titanium tube 21 attached to cap 22. There is an electrical connection from the tube 21 to an electrical socket (not shown) for connection to a power supply in the cap 22.

When the cathode electrode 13 is inserted within the housing 11 (as indicated in Fig the collar 18 engages and tightens on complementary threaded end 16.

The chlorinator 10 shown in Fig 1. is assembled for operational use. During the operation of the chlorinator calcium carbonate deposits on the outer surface of the cathode tube 21. When the calcium carbonate deposits effect the efficiency of the electrolytic cell, or indeed at any stage, the electrical power to the chlorinator can be switched off and electrical leads disconnected from electrical connection 23. The collar 18 may be unscrewed and removed from the housing 11 and the cathode 13 may then be withdrawn from the housing 11. The calcium carbonate deposits on tube 21 can then be cleaned by any suitable method, such as by scraping off the deposits or allowing the deposits to dry then removing them by tapping the tube 21. If the cathode 13 is unable to be used to reassemble the chlorinator 10 a replacement cathode may be substituted. The use of a replacement cathode enables cleaning and repairs to be carried out while the chlorinator is operating. Several days without the operation of the chlorinator may result in a swimming pool becoming turbid and/or green with algae and microorganisms and being unsuitable for swimming purposes.

The chlorinator of the present invention provides a number of advantages over the prior art. The electrodes of the chlorinator can be electrically disconnected and the cathode removed, cleaned and 20 returned within the housing without causing damage to the cap and cathode. Another advantage of the present invention is that the .'cathode of the chlorinator may be easily removed and replaced without replacing the entire chlorinator unit should the cathode break down, be damaged or require cleaning. This operation can normally be performed without the use of a tool. Also the threaded end 17 means that the entire chlorinator 10 can be removed for replacement or cleaning, if necessary. For example, where the calcium carbonate deposits bridge between the cathode and anode, the inverted housing 11 can be used as a receptacle for dilute cleaning acid and still protect the 30 anode 12 from damage.

It will of course be realized that while the foregoing has been given by way of example, all such and other modifications are variations thereto as would be apparent to, persons skilled in the art are 2972A deemed to fall within the broad scope and ambit of this invention as herein set forth.

S.

S S 2972A

Claims (8)

1. An electrolytic chlorinator device comprising an elongate body having a base and a top, said base being adapted for releasable water tight connection to a pipe to form a T-junction therewith with said body being substantially upright, and said top being releasably engaged with said body in a water tight arrangement, said chlorinator further comprising an elongate anode which is mounted within said body and aligned therewith and an elongate cathode which is mounted to said top, extends into the interior of said body, and is juxtaposed with said anode wherein said cathode is removable from said body interior for cleaning by releasing said top from said body and moving said top to withdraw said cathode from said body.

2. The device as claimed in claim 1 and including a gas sensing electrode mounted within said top.

3. The device as claimed in claim 1 and including a gas sensing electrode mounted within said body adjacent said top.

4. The device as claimed in any one of claims 1-3 wherein said anode and cathode are each tubular with one being located within the other when juxtaposed.

The device as claimed in claim 4 wherein said cathode is located within said anode.

6. The device as claimed in claim 4 or 5 wherein said tubular anode and cathode each have a substantially hollow cylindrical configuration.

7. The device as claimed in any one of claims 1-5 wherein said body comprises a •venturi type chlorinator.

8. An electrolytic chlorinator substantially as herein described with reference to the drawings. Dated this 1 1 th day of July 2003 WATERMAID PTY LTD and AQUATRONICS PTY LTD By :FRASER OLD SOHN Patent Attorneys for the Applicant 2972A