AU782783B2

AU782783B2 - An underwater light

Info

Publication number: AU782783B2
Application number: AU45151/00A
Authority: AU
Inventors: Ian Guthrie
Original assignee: Spa Electrics Pty Ltd
Current assignee: Spa Electrics Pty Ltd
Priority date: 2000-07-10
Filing date: 2000-07-10
Publication date: 2005-08-25
Anticipated expiration: 2020-07-10
Also published as: AU4515100A

Description

r P/00/01i1 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: SELBE=GFEP46G)N&EI ~A 704 S&PAELEeTFRI SPTY LTD Applicant method of performing it known to me: W %SKkR0h% ,1%PCTCCUPPC"0F04 DOC 2 AN UNDERWATER LIGHT The present invention relates to an underwater light, and to such a light that includes a sealed electrical connector. The invention has principle application to lights such as for use in swimming pools or spas and it will therefore be convenient to describe the invention in relation to that application.

However, it should be appreciated that the invention may have wider application, such as in aquariums or in other liquid containing vessels.

Underwater lights need to be securely sealed against ingress of water, so that electrical wires and fittings are protected from contact therewith. Water contact with the electric's of an underwater light typically could have minor but inconvenient consequences, by disabling the light through short circuit or corrosion. This may result in a blown fuse or a tripped circuit switch, or more inconveniently, the lamp or globe, may be blown requiring replacement.

15 Alternatively, such water contact may have far more serious consequences, by ***electrocution of swimmers or bathers although generally, lighting in such areas operates at extra low voltage, so that there is normally little risk of electrocution.

In view of the inconvenience associated with repair or replacement of underwater lights, effective sealing of lights against ingress of water is 20 important.

It is an object of the present invention to provide an improved or alternative form of sealed electrical connector, and an arrangement for sealing an electrical connector, for preventing or minimising intrusion of moisture or liquid into or through the connector.

25 An underwater light which includes an electrical connector having a solid, electrically conductive shaft which has a first end for connection to an electrical cable and a second end for connection to an electrical device, the underwater light including a sealed compartment which accommodates the lamp or globe of the light and said conductive shaft extends through an opening in a wall of the compartment so that said second end is positioned within said compartment for connection to said lamp or globe, and said first end is positioned outside said compartment and is secured to said electrical cable through which electricity can be supplied to pass through said shaft for operation of said lamp or globe, said connector including securing means to secure it in position extending W.UAIieAndreASpec 18285.doC through said opening of said compartment wall and sealing means disposed adjacent said first end for sealing said connector to said compartment wall against leakage past said first end into said compartment.

The present invention is distinguished from previous arrangements in which an electrical cable extends directly into connection with an electrical device. In underwater lights, the sealed compartment that accommodates the lamp or globe can become flooded in the event that the plastic casing of the cable that encloses the cable wires is pierced or broken. That permits moisture or liquid to enter the cable and to track through the cable into the sealed compartment. However, by use of the present invention, the electric cable can be attached to the first end of the shaft and any water that has entered the cable through a break in the plastic cable casing, progresses only to the connection between the cable and the first end. It cannot progress further, *:00e because the shaft is solid so that any liquid or moisture cannot track through it 0. 0.0 15 in the manner it tracks through the cable. Additionally, liquid or moisture is also prevented from travel along the outside of the shaft by the sealing means disposed adjacent the first end.

o. In a preferred form of the invention, the first end of the connector is formed integrally with the shaft and is formed to have a hexagonal configuration 20 in plan view. It is preferred that the first end have a circumference of greater radial extent than the shaft to produce an axially facing surface so that the first end can be secured in position by bearing engagement of that surface against an opposed surface of the compartment wall. In this form of the invention, the compartment wall may be formed, such as by moulding, to have a recess of 25 similar, but slightly larger configuration than that of the first end, to accept the first end either partly or fully, without permitting it to rotate. Thus, once the first end is inserted into the recess, the connector is retained against rotation. The first end may equally be formed to have an alternative plan configuration, such as square and achieve the same outcome.

The first end preferably includes facility for connection to an electrical supply and for example, the first end may include a threaded bore for threadably receiving a threaded electric cable terminal end. Alternatively, the bore may accept the terminal end of an electric cable as a snap or friction fit.

W Au ewkere S PecK8i8285 doc 3a The second end of the shaft of the connector preferably is threaded for receipt of a nut that can be tightened to secure the connector to the compartment wall.

Preferably the connector includes load bearing means against which the nut can bear when it is threaded onto the shaft in the operative installed condition of the connector. Such load bearing means is useful for bearing extra load exerted on the connector, such as by moulding creep, if the wall through which the connector extends is formed of a moulded material. The load bearing means preferably takes the form of a spring or crinkle washer.

The second end of the washer can be configured or arranged in any suitable manner for electrical connection to a lamp or globe. In one arrangement, the second end may include a bore like that described for the first end, although in the preferred arrangement, an electrical terminal is sandwiched in use between the nut of the second end and the surface of the compartment 15 wall the nut is tightened against. The terminal is required to be in electrical contact with the shaft of the connector and is arranged to be connected, either directly or indirectly with the electrical device.

W :Jube'A rewSpec618285doc The sealing means can take any suitable form and in the preferred form a seal, in particular a compression seal, is disposed between the axially facing surface of the first end and an opposed axially facing surface of the compartment wall. Most preferably, the opposed axially facing surface of the wall is formed by a step surface formed in the recess and the seal is disposed between the opposed surfaces.

The attached drawings show an example embodiment of the invention of the foregoing kind. The particularity of those drawings and the associated description does not supersede the generality of the preceding broad description of the invention.

Figure 1 is a cross-sectional view of an installed sealed electrical connector according to a preferred embodiment of the present invention.

Figure 2 is a perspective view of an electric terminal for use with the sealed electrical connector of Figure 1.

15 Figure 3 is a cross-sectional view of a backing plate of an underwater light that can employ the sealed electrical connector of Figure 1.

S" Figure 1 shows a sealed electrical connector 10 for use in the underwater light shown in Figure 3. The connection 10 includes a shaft 11 of elongate cylindrical cross-section. The shaft 11 includes a first end 12 and a 20 second end 13. The first end 12 is formed as a head 14 of hexagonal crosssection which extends radially beyond the outer surface 15 of the shaft 11. The head 14 of the first end 12 is formed integrally with the shaft 11 of a suitable electrically conductive material, such as nickel plated brass.

The second end 13 includes a threaded section 16 to threadedly receive 25 a threaded nut 17. Like the head 14, the nut 17 is of hexagonal cross-section, so that it can be fitted with a standard tool, such as a spanner or socket.

The connector 10 extends through an opening 18 in the wall 19, of the compartment of an underwater light that houses the lamp or globe of the light.

The wall 19 includes a recess 20 which has a hexagonal plan crosssection sized to closely receive the head 14 and to prevent rotation of the head 14 when received therein. The recess 20 includes an axial wall 21 and a radial wall 22. The radial wall 22 is in opposed facing relationship with the radial extent 23 of the head 14 beyond the outer surface 15 of the shaft 11. Between the radial wall 22 and the radial extent 23 is disposed a compression seal 24 WJ eOnd r &M.SmeI 18285 doc which upon installation, engages against each of the axial wall 21, the radial wall 22 and the radial extent 23, to seal against leakage therepast.

As shown, the wall 19 includes an axially depending tubular section having an axially facing annular end surface 26. Disposed adjacent the end surface 26, is an electrical terminal 27. The terminal 27 is shown in more detail in Figure 2 and from that figure it can be seen that it includes a circular opening 28 defined by substantially annular ring 29 and includes a depending leg The terminal 27 is largely planar, as shown. The leg 30 is in use, arranged to be in electrical connection with the lamp or globe of the underwater light..

Referring back to Figure 1, the electrical connector 10 further includes a spring washer 31 disposed between the nut 17 and the terminal 27.

The arrangement of Figure 1 is such that the shaft 11 of the connector extends through the opening 18 of the wall 19, whereafter the terminal 27 and the spring washer 31 are located over the threaded section 16, whereafter the 15 nut 17 is threaded onto the threaded section 16 and tightened down that section to securely fasten the connector 10 in place. Upon tightening of the nut 17, the compression seal 24 is caused to deform into sealing engagement with each of the axial wall 21, the radial wall 22 and the radial extent 23. By this deformation, liquid or moisture on the first end 12 side of the connector 20 cannot progress through the opening 18 of the wall 19. This is particularly useful for underwater lights and a cross-sectional view of a backing plate of such a light, taken through openings suitable to receive a connector 10, is shown in Figure 3. In that figure, the wall 19 of Figure 1 is identified by the reference numeral 32 and has a lens 33 connected thereto, which is shown in 25 dot outline. The lens 33 and the wall 32 accommodate a lamp or globe (not shown) which is connected to an electric power supply via a pair of connectors of the kind illustrated in Figure 1 which are inserted within and accommodated by the openings 34 and 35 in the backing plate 32. Each of the openings 34 and 35 is substantially identical in configuration to the opening 18 described in relation Figure 1.

The wall 32 forms part of a compartment of an underwater light which is connected to the wall of a pool or spa or the like and it is normal for the wall on the left hand side thereof as shown in Figure 3, to be exposed to the liquid within the spa or pool. Accordingly, the arrangement shown in Figure 1 W.'uQe\A ncreMSoed 18285..oc 6 prevents that liquid from flowing through the openings 34 and 35 and into the cavity defined by the wall 32 and the lens 33.

Referring back to Figure 1, the first end 12 of the connector 10 includes a threaded bore 36 for connection of an electric cable (not shown) of an electric supply, such as a mains supply. The inner most end of the bore 36 can be employed for metal to metal electrical connection. Advantageously, the cable terminates at the bore 36, so that any moisture or liquid which has entered the cable through a break in the plastic cable casing, will flow no further than the inner end of the bore. Thus, that moisture or liquid cannot flow into the compartment defined by the wall 32 and the lens 33, thereby protecting a lamp or globe within that compartment.

An underwater light including a sealed electrical connector according to the present invention is of quite simple form but provides very effective water tight connection through the compartment wall of an underwater light.

15 The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the above description.

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Claims

1. An underwater light which includes an electrical connector having a solid, electrically conductive shaft which has a first end for connection to an electrical cable and a second end for connection to an electrical device, the underwater light including a sealed compartment which accommodates the lamp or globe of the light and said conductive shaft extends through an opening in a wall of the compartment so that said second end is positioned within said compartment for connection to said lamp or globe, and said first end is positioned outside said compartment and is secured to said electrical cable through which electricity can be supplied to pass through said shaft for operation of said lamp or globe, said connector including securing means to secure it in position extending through said opening of said compartment wall and sealing means disposed adjacent said first end for sealing said connector to said compartment wall 15 against leakage past said first end into said compartment.

2. An underwater light according to claim 1, wherein said first end of said connector is formed integrally with said shaft. 20

3. An underwater light according to claim 2, wherein said first end of said ooo. connector is formed to have a hexagonal configuration in plan view of greater too: circumferential radial extent than said shaft.

4. An underwater light according to claim 2, wherein said first end of said 25 connector has a square configuration in plan view of greater circumferential radial extent than said shaft. An underwater light according to any one of claims 1 to 4, wherein said compartment wall is formed to have recess to partly or fully accommodate said first end of said connector, which recess is configured to closely receive said first end of said connector to retain said connector against rotation.

W:.u eAndrepecA618285.doC 8

6. An underwater light according to any one of claims 1 to 5, wherein said first end of said connector includes a threaded bore for threadably receiving the terminal end of an electric supply cable.

7. An underwater light according to any one of claims 1 to 5, wherein said first end of said connector includes a bore which accepts the terminal end of an electric supply cable as a snap or friction fit.

8. An underwater light according to any one of claims 1 to 7, said second end of said connector being threaded to threadably receive a nut thereon.

9. An underwater light according to claim 8, wherein said connector includes load bearing means between said nut and said compartment wall and against which said nut can bear in an operative installed condition of said 15 connector.

10. An underwater light according to claim 9, said load bearing means being provided by a spring or crinkle washer. 20

11. An underwater light according to any one of claims 1 to 10, including an too$ electrical terminal depending from said second end of said connector. 0o

12. An underwater light according to claim 11, when dependant on claim 8, wherein said electrical terminal is sandwiched between said nut and said compartment wall.

13. An underwater light according to any one of claims 1 to 12, said sealing means being sandwiched between an axially facing surface of said first end and an opposed axially facing surface of said compartment wall.

14. An underwater light according to claim 143 when dependent on claim wherein said axially facing surface of said compartment wall is formed by a step surface formed in said recess to partly or fully accommodate said first end of said connector. WldJeWndreweSpecft618285.dMc 9 An underwater light substantially as here and before described with reference the accompany drawings. DATED: 6 April, 2005 PHILLIPS ORMONDE FITZPATRICK Attorneys for: SPA ELECTRICS PTY LTD W:uJulieAndreASpecd18285 doc