AU2012101527A4 - Waterproof light assembly - Google Patents

Abstract

Underwater light assembly Abstract A waterproof light assembly 10 comprising a lens 30 and a light source chamber located between a rear surface of the lens 30. The light assembly 10 including a backing plate 60. A light source 50 located within the light source chamber, and a secondary chamber 70 located adjacent to the light source chamber, the secondary chamber 70 having a power cable input aperture. One or more power transmission pins 120 extend between the light source chamber and the secondary chamber 70, the pins 120 having a leading end connected to the light source 50, and a trailing end connectable to a power cable 123. Fig. 1

Description

AUSTRALIA Patents Act 1990 Innovation Patent Specification Title: Waterproof light assembly Applicant(s): Waterco Limited Inventor(s): Pradeep Kumar Tandon Agent: © COTTERS Patent & Trade Mark Attorneys The following is a full description of the invention which sets forth the best method known to the applicant of performing it.

2 Waterproof light assembly Field of the Invention The present invention relates to a waterproof light assembly. In particular, the present 5 invention relates to an underwater light assembly for use with halogen lights. However, it will be appreciated that the light assembly can be used with other light types such as LED lights. Background of the Invention 10 Lights are widely used in swimming pools and spas, and other such applications where they are exposed to moisture, or completely submerged. Placing a light in a submerged location under the water surface often results in a visually appealing light source, on account of the diffusion of light in the water. This provides interesting light when seen from above or below the water surface. However, there are inherent difficulties associated with under water 15 lighting. A first problem is that the light housing is known to leak over time. This reduces the lifespan of the light source, such as an LED or halogen globe, which necessitates a costly and often time consuming replacement, generally requiring the services of a qualified electrician. 20 A further problem is that in order to adequately seal the light source against moisture ingression, it is common for heat dissipation problems to arise. This is because the sealed light housing does not provide adequate thermal conductivity to permit the considerable amount of heat generated by the light source to be dissipated into the surrounds. Again, this can result in a reduction of the lifespan of the light source. 25 Halogen lights sources are commonly used in swimming pool lights. Halogen globes provide a reasonable operating lifespan and are less costly to purchase than LED equivalents. However, halogen globes typically generate a considerable amount of heat during operation. Accordingly, it is common for overheating to occur. Damage by overheating can result in a 30 reduction in the working life of the halogen globe, and may result in damage to the light fitting or even the pool surrounds, which can be significantly more costly to repair for the consumer.

3 Object of the Invention It is an object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages, or to provide a useful alternative. 5 Summary of the Invention In a first aspect, the present invention provides a waterproof light assembly comprising: a lens; a light source chamber located between a rear surface of the lens and a backing plate; 10 a light source located within the light source chamber; a secondary chamber located adjacent to the light source chamber, the secondary chamber having a power cable input aperture, wherein one or more power transmission pins extend between the light source chamber and the secondary chamber, the pins having a leading end connected to the light 15 source, and a trailing end connectable to a power cable. The secondary chamber preferably is filled with a thermally conductive resin. The pins preferably extend through and are ultrasonically welded to a wall of the backing 20 plate. The waterproof light assembly further preferably comprises a rim secured to the light source chamber, the rim including a plurality of water circulation holes. 25 The waterproof light assembly further preferably includes a mounting plate securable to a fixed surface, the mounting plate having an annular skirt, the skirt extending generally away from the fixed surface, and radially inwardly, wherein one or more cut-outs are formed in the skirt, the cut-outs being adapted to receive corresponding mounting tabs formed on the rim. 30 4 Brief Description of the Drawings A preferred embodiment of the invention will now be described by way of specific example with reference to the accompanying drawings, in which: Fig. 1 is an exploded view of an underwater light assembly; 5 Fig. 2 is a further exploded view of the underwater light assembly of Fig. 1 including a wall mounting ring; Fig. 3 is a perspective view of a mounting plate of the underwater light assembly of Fig. 1 and 2; Fig. 4 is a rear view of the backing plate and rim of the underwater light assembly of to Fig. 1; Fig. 5 is a perspective view of the rim and front lens of the underwater light assembly of Fig. 1; Fig. 6 is a rear view of the underwater light assembly of Fig. 1; and Fig. 7 is a perspective view of the underwater light assembly of Fig 1. 15 Detailed Description of the Preferred Embodiments An underwater light assembly 10 is depicted in Figs. 1 to 4. The underwater light assembly 10 includes a front lens 12. The front lens 12 enables the light to be diffused under the water, and may be provide with a textured, coloured, curved or patterned finish to provide a 20 desired light diffusion effect. In particular, the front lens 12 may be coloured, in order to provide a desired light coloration in the water. The front lens 12 is removably connected to a rim 14, which has, in the embodiment depicted, eleven apertures 16 formed in it. The apertures 16 as well as being visually pleasing, permit water to flow around the sides of the rim 14, which is advantageous for cooling of the light assembly 10. In addition, the 25 apertures 16 enable access for a tool to remove fasteners 36. The front lens 12 is connectable to the rim 14 using a first engagement formation 18, generally in the form of a projecting arm or other such member. A second engagement formation 19 includes an apertures 20 and an adjacent step 27, formed around the 30 circumference of a circular hole 21 formed in the rim 14. The front lens 12 engages the rim 14 from the front. The rim 14 is depicted in isolation Fig. 5. When the front lens 12 is rotated, the first engagement formation 18 engages with the 5 second engagement formation 19, holding the front lens 12 in position. Accordingly, the front lens 12 can be removed for replacement by rotating the front lens 12 relative to the rim 14, in an opposing rotational direction relative to the direction of securement. This permits the user to readily change the colour of the light as desired to achieve a different 5 lighting effect. A lens body 30 is located in front of the light source (which is generally a halogen globe 50). The lens body 30 is transparent or opaque to permit light to readily pass therethrough. Generally the lens body 30 is manufactured from polycarbonate or another suitable 10 thermoplastic polymer. The lens body 30 is generally circular, and has an annular flange 32 formed around its circumference. The flange 32 has twelve holes 34 formed in it on an equal pitch circle diameter. The holes 34 are adapted to receive bolts 36. The holes 34 correspond with twelve holes formed on a backing plate 60. The backing plate 15 60 and lens body together define a cavity, or light source chamber, which houses the halogen globe 50, mounted within a globe holder 52. A rubber O-ring 40 is located within a circular groove or channel formed in the rear surface of the lens body 30. By fastening each of the twelve bolts 36 relative to nuts 38, the O-ring 20 40 is compressed, which creates a watertight seal between the lens body 30 and the backing plate 60, preventing the unintentional ingress of water into the globe 50 or other light source cavity. On a rear side of the backing plate 60, a terminal chamber 70, or secondary chamber 70 is 25 formed. In the embodiment depicted in the drawings, the terminal chamber 70 has a generally rectangular prism shaped profile. However, it will be appreciated that the terminal chamber 70 may be provided in other geometric configurations such as cylindrical. The rear of the terminal chamber 70 is sealed with a removable terminal cover 100. A 30 gasket seal 110 is located between the terminal chamber 70 and the terminal cover 100, to define a sealed enclosure 72 within the terminal chamber 70. The terminal cover 100 is secured to the terminal chamber with four screws 114, which act to compress the gasket seal 110, to make the sealed enclosure 72 watertight. The sealed enclosure 72 is filled with a thermally conductive resin. The resin serves the dual purposes of dissipation of heat, and 6 reducing the risk of water ingression into the globe 50 cavity. The terminal cover 100 includes an opening 110 which enables a low voltage power cable 122 to enter into the sealed enclosure 72. The opening 110 is sealed with a waterproof 5 gland nut 112 type seal. Two pins 120 are located within the terminal chamber 70. The pins 120 extend through a wall of the terminal chamber 70 into the watertight globe 50 cavity between the lens body 30 and the backing plate 60. The pins 120 are made from brass with nickel plating or 10 another suitable conductive material. The pins 120 are ultrasonically welded to the wall of the terminal chamber 70. A leading end of each pin 120 is received within the ceramic globe holder 52, and secured with small screws 73 connected to the globe holder 52. The trailing end of each pin 120 is 15 located within the terminal chamber 70. Each pin 120 trailing end includes a socket 122 for receiving one of the active or neutral low voltage cables 123. Each socket 122 has a screw adjuster 129 for securing the cables 123. The ends of the cables 123 may include a swagged band 124 or other such fitting to reduce the likelihood of the cables 123 pulling out of the socket 122. The screw adjuster 129 includes screws 127 which hold the swagged 20 band 124 in position within the socket 122. The underwater light assembly 10 includes a mounting plate 150. The mounting plate 150 is secured to the wall of a swimming pool or spa with screws 152 which engage with plastic screw anchors 154. The screw anchors 154 are inserted in holes formed in the wall of the 25 pool. A plurality of holes are formed in the mounting plate 150. This enables the installer to choose holes which are most convenient, based on where holes can be most readily formed in the pool or spa. In the embodiment depicted in Fig. 2, a wall mounting ring 200 is included in the underwater 30 light assembly 10. The wall mounting ring 200 is secured to the wall of the swimming pool or spa by cementing. In this embodiment, four screws 202 are used to secure the mounting plate 150 to the wall mounting ring 202. Advantageously, a pool builder can choose whether the wall mounting ring 200 is used, or if 7 the mounting plate 150 is secured directly to the pool wall. The backing plate 150 includes a mounting lug 160. The mounting lug 160 extends away from the body of the backing plate 150, away from the wall of the pool or spa. As shown in 5 Fig. 1, and the detail of Fig.3, the mounting lug 160 has a generally square upper surface 162, and two triangular side support gussets 164. A hole is formed in the square upper surface 162. The mounting plate 150 includes a central aperture 156 for receiving the low voltage power 10 cable 123. The rear side of the mounting plate 150 is shown in Fig. 6, and the rear side of the backing plate 60 is also visible in that drawing, through the aperture 156. The mounting plate 150 includes an annular skirt or flange 170 having three cut-outs 172 located around the outer circumference, which are equally spaced relative to each other, at 15 approximately 1200. The skirt 170 extends away from the pool, and tapers or curves radially inwardly, to define a shoulder or step. The cut-outs 172 in the skirt 170 are adapted to receive three corresponding tabs 174 which are located around the circumference of the rim 14. 20 Accordingly, in order to secure the rim 14 to the mounting plate 150, the tabs 174 are inserted into the cut-outs 172, and the rim 14 is then rotated, such that the tabs 174 slide behind the skirt 170. Because the skirt 170 is stepped or tapered inwardly, this has the effect of securing the rim 14 against the mounting plate 150. Fig. 7 depicts the rim 14 secured to the mounting plate 150. 25 A slot 19 is formed on the rim 14. The slot 19 is adapted to line up with the hole formed in the square upper surface 162 of the mounting lug 160. When the rim 14 is located in the assembled position, a screw 21 is inserted through the slot 19, to secure the rim 14 to the mounting plate 150. 30 As shown in the rear view of the rim 14 and backing plate 60 in Fig. 4, the backing plate 60 includes four screws 180 which pass through the radial flange of the backing plate 60 and secure it to the rim 14.

8 In order to change the halogen globe 50, the screw 21 is initially removed. This enables the rim 14 to be pivoted relative to the mounting plate 150, to undo the twist lock between the rim 14 and the mounting plate 150. When the tabs 174 leave the cut-outs 172, the rim 14 is free to be pulled away from the mounting plate 150. The lens body 30 and backing plate 60 5 can then be removed together. A sufficient length of the low voltage power cable is located either behind the mounting plate 150, or more preferably between the mounting plate 150 and the backing plate 60. This enables the lens body 30 and backing plate 60 to be moved to a remote location, above the pool water level. After drying of these components, the twelve bolts 36 are removed, to provide access to the halogen globe 50, which can be simply 10 replaced, and the process reversed to re-install the underwater light assembly 10. The rear surface of the backing plate 60, defines a truncated cone shaped projection 180, around the globe holder 52. This provides an internal space for the globe holder 52, and defines an air cavity. The circumferential region, of the backing plate 60 defines a well 192, 15 around the truncated cone shaped projection 180, and this well 192 provides space for one or more coils of the cable 114 to be stored. Although the underwater light assembly has been described with respect to a halogen globe 50, it will be appreciated that other lights such as LED may be used in the underwater light 20 assembly 10. Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. 25

Claims (5)

1. A waterproof light assembly comprising: a lens; a light source chamber located between a rear surface of the lens and a backing plate; a light source located within the light source chamber; a secondary chamber located adjacent to the light source chamber, the secondary chamber having a power cable input aperture, wherein one or more power transmission pins extend between the light source chamber and the secondary chamber, the pins having a leading end connected to the light source, and a trailing end connectable to a power cable.

2. The waterproof light assembly of claim 1, wherein the secondary chamber is filled with a thermally conductive resin.

3. The water proof light assembly of either of claims 1 or 2, wherein the pins extend through and are ultrasonically welded to a wall of the backing plate.

4. The waterproof light assembly of any one of the preceding claims, further comprising a rim secured to the light source chamber, the rim including a plurality of water circulation holes.

5. The waterproof light assembly of claim 4 further including a mounting plate securable to a fixed surface, the mounting plate having an annular skirt, the skirt extending generally away from the fixed surface, and radially inwardly, wherein one or more cut-outs are formed in the skirt, the cut-outs being adapted to receive corresponding mounting tabs formed on the rim. Waterco Limited By Patent Attorneys for the Applicant ©QCOTTERS Patent & Trade Mark Attorneys