AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR AN INNOVA TION PATENT ORIGINAL Name of Applicant: ROADS AND TRAFFIC AUTHORITY OF NEW SOUTH WALES Actual Inventor: Graeme PATTISON Address for Service: FRASER OLD & SOHN Patent Attorneys PO Box 560 MILSONS POINT NSW 1565 Invention Title: TRAFFIC SIGNAL LANTERN HOUSING The following statement is a full description of this invention, including the best method of performing it known to us: 51341-AU-DI ' 51341-AU-D1 TRAFFIC SIGNAL LANTERN HOUSING Field of the Invention The invention relates to traffic signals and, in particular, to a traffic signal lantern 5 housing. The invention has been developed, inter alia, for use with conventional vertically orientated red, amber and green traffic signals and will be described hereinafter with reference to this application. However, it will appreciated that the invention is not limited to this particular field of use and is applicable to other traffic control signals in any preferred combination including, but not limited to, turn arrows 10 and special vehicle signal designations such as buses. Background of the Invention Traffic signals or lights have long been used in a large number of locations to control the flow of both automobile traffic and pedestrian traffic. Traffic signals are typically 15 controlled from a traffic signal control box disposed at a convenient location proximal to the traffic signals. For example, a four way intersection may include eight or more sets of traffic signals which are each connected to the control box. The traffic signal control box is configured to operate the traffic signals in a 20 predetermined manner. This predetermined manner can be dynamic whereby the signals are actuated in a different sequence at different times of the day or in response to some predetermined number of vehicles crossing the intersection. The traffic controller is connected to mains voltage, 240V AC or 11 OV AC, and provides signals at this voltage to be received by the traffic signal elements in a predetermined manner 25 so as to illuminate them to provide the traffic signals. The use of mains voltage in providing power to the traffic signals has the obvious disadvantages. Typically, the connections from the traffic signals control box to each set of traffic signals is provided under ground and the mains voltage is terminated at 30 or near the top of a pole supporting the traffic signals. These wires are then patched to respective traffic signal lamps. Aside from the laying of mains voltage cables underground and across roads, the traffic signal poles may become electrically live in the event that the traffic signal control box cables are moved or severed or otherwise disconnected by accident with the pole. It is relatively common for vehicles to impact 1 .* J1.'+1-A U -)1 on the poles. This is particularly disadvantageous in jurisdictions where emergency service workers are not able to attend to accident or trauma victims until a licenced electrician certifies that a vehicle having impacted with a traffic signal pole or the traffic signal pole is not electrically live. Also, a worker must often replace the entire 5 latern housing if the latern target board or backboard is damged by objects extending from vehicles such as truck antenna. In part because of the use of mains voltage to power the traffic signals, conventional traffic signal lantern housings are substantially sealed units with doors or other access 10 portals which must also provide weatherproof seals so as to keep any moisture away from the mains powered cables or connections, and signals. In practice, relatively expensive roll formed or otherwise formed metallic enclosures are provided for this purpose. Unfortunately, the cost of these lantern housings is relatively expensive and they typically do not properly seal the traffic light signals allowing moisture to enter 15 undesirably. This can cause corrosion or short-circuiting in the lantern housing lamp(s). When maintenance or replacement of the traffic signals or lighting elements or lamps therein is required, a maintenance worker ascends a ladder or the like and opens the 20 door to the sealed lantern housing to replace a lamp or the lantern housing itself, for example. The conventional traffic light lantern housings are practically too heavy for a worker to safely carry up a ladder so as to replace an entire traffic signal lantern housing. This has the obvious disadvantage that additional labour and/or heavy lifting equipment is required to undertake such a task. This is further disadvantageous in so 25 far as any workers must also connect and disconnect mains voltage in the replacement of a traffic signal lantern housing. Genesis of the Invention The genesis of the present invention is a desire to provide a traffic light lantern 30 housing which overcomes or substantially ameliorates one or more of the disadvantages of the prior art, or to provide a useful alternative. 2 ' ~J I't1-XU-iJ1 Summary of the Invention According to a first aspect of the invention there is provided a traffic signal lantern housing comprising: frame configured to be supported a predetermined height above a ground 5 surface; a sheet like target board configured to have one face thereof removably mountable to the frame; one or more lamp housings configured to be mounted to the opposite face of the target board to the frame; and 10 at least one sealed lamp module configured to be removably mounted within the lamp housing, the sealed lamp module having a plurality of LED light sources configured to be actuated to indicate a traffic signal, the sealed lamp module including a connection means to provide electrical connections between an extra low voltage source and the plurality of LED light sources. 15 In preferred embodiments, the lamp housings are configured to be removably mounted, and the lantern housing includes at least one lens element configured to be disposed adjacent the lamp module LED light sources and face away from the target board. 20 Preferably, the traffic signal lantern housing includes three sealed lamp modules configured to be vertically spaced apart in substantially a straight line, and three sealed lamp modules with one module configured to be disposed in each lamp housing. 25 In preferred embodiments, each lamp module includes an electrical connection disposed on the outside thereof or extending therefrom and configured for engagement with a corresponding connector configured to supply power to each lamp module. 30 It can therefore be seen that there is advantageously provided a traffic signal lantern housing in which individual lamp housings and lamp modules can be individually changed with little risk of electrocution and without the need of any additional labour or lifting equipment. It will be appreciated that the entire traffic signal lantern 3 . JLy+1-IAU-L11 housing or components thereof can be carried by one person up a ladder with significantly more ease than is possible with the prior art. Brief Description of the Drawings 5 A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a front perspective view of part of a traffic signal lantern housing according to the preferred embodiment; Fig. 2 is a rear view of the traffic signal lantern housing of Fig. 1; 10 Fig. 3 is a side view of the traffic signal lantern housing of Fig. 1; and Fig. 4 is an elevated perspective view of a bracket of the traffic signal lantern housing of Fig. 1. Detailed Description 15 Referring to the drawings generally, there is shown the traffic signal lantern housing 1 of the preferred embodiment. The traffic signal lantern housing 1 includes a frame 2 configured to be supported a predetermined height above a ground surface over or adjacent a road or intersection (not illustrated). This height is selected to be sufficient to allow clearance thereunder to vehicular or pedestrian traffic. 20 For example, where the traffic signal lantern housing 1 is to be disposed over a road surface, sufficient clearance must be provided for trucks or other tall vehicles to pass but also to allow clearance for antenna or other items projecting from a vehicle. In the case where the traffic signal lantern housing 1 is to be disposed adjacent a road 25 surface, a clearance height sufficient to allow pedestrian traffic thereunder needs to be provided rather than for the much higher vehicle traffic. The frame 2 is configured to be supported by a traffic pole (not illustrated) extending a predetermined height above the ground surface. The traffic lantern housing 1 30 further includes a sheet-like backboard 3 known as a target board having a front face 4 and a rear face 5. The target board 3 is formed from a painted metal or a corrosion resistant metal, however, it will be appreciated that the target board 3 may be formed from any preferred material including plastics and die cast alloys. The target board 3 is intended to increase the visible contrast of the traffic signals. 4 - 31341-AU-U1 The rear face 5 of the target board 3 is configured to be disposed against the frame 2. This is best shown in Fig. 2. In this embodiment, bolts 7 are disposed through apertures 8 of the target board 3 and engage through the frame 2 to secure the two 5 together. The frame 2 and apertures 8 are best seen in Fig. 4. It will be appreciated that preferred means can be used to secure the target board 3 to the frame 2, for example, self-tapping screws. The traffic signal lantern housing 1 includes three lamp housings 10 each configured 10 to be removably mounted to the front 4 of the target board 3. The lamp housings 10 are removably mountable to the target board front 4 by means of mounting screws 11. The screws 11 are configured to be disposed through apertures 12 in the lamp housings 10 and through corresponding apertures 13 in the target board to releasably engage with apertures 14 disposed in the frame 2. It will be appreciated that in other 15 embodiments of the invention (not illustrated) the mounting screws 11 can releasably engage with the target board 3 to releasably retain the lamp housings 10 thereto. The lamp housings 10 are removably mounted to the vertically spaced apart in a substantially straight line to the target board 3. The lamp housings 10 are configured 20 to be disposed substantially vertically when the traffic signal lantern housing 1 is mounted to a traffic pole (not illustrated) or otherwise above a ground surface. A front 15 of each lamp housing 10 includes four spaced apart visor mounting tabs 16, although all four are not clearly shown in the drawings. The tabs 16 are 25 configured to releasably receive a lamp visor 17 such that each lamp visor extends a predetermined distance from the front 15 of the lamp housings 10. The visors perform the well known function of controlling the direction of the light emitted by each lamp and to also prevent illumination by the sun that may result in sun phantom problems, for example. The visors 17 are formed from plastic or painted or corrosion 30 resistant metal, however, it will be appreciated that these can be formed from any preferred material that can tolerate an outdoor environment. Each lamp housing 10 is configured to releasably receive a sealed lamp module 20 such that the lamp module is positioned to project light indicative of a traffic signal 5 M341-AU-VI from the lamp housings 10. The lamp modules 20 are shown to be releasably mounted to the target board 3 by means of mounting screws (not illustrated). In other unillustrated embodiments, the lamp modules 20 are configured to be releasably mounted to the lamps housings 10 and/or the frame 2 as preferred. 5 Although not illustrated, the lamp modules 20 include a plurality of LED light sources disposed in substantially the same plane and pointed in substantially the same direction and configured to be actuated to indicate a traffic signal. The light signal produced by each lamp housing is protected by a visor 17. Each lamp module 20 has 10 at least one associated lens element (not illustrated). The lens element is configured to be disposed in front of the LED light sources and to assist in directing the light away from the modules 20, improve contrast and reduce sun phantom problems. In particularly preferred embodiments, the lens element is formed from a plurality of lenses such that one lens is provided for each LED light source. Most preferably, the 15 lens element forms a front window 24 of each lamp module 20, however, this can be spaced apart from the modules 20. It will be appreciated, however, that the lamp module lens element is not necessary and the lens element integrated into the front of each LED diode can serve the purpose 20 if desired. A separate front window 24 not being or including any lens element can also be provided. Each lamp module 20 is configured to be driven by extra low voltage electrical power, for example, 42V DC. An electrical connection means (not illustrated) is disposed on 25 the lamp modules 20 or extends therefrom such as by cable extending from the modules 20 and terminating at a connector. The module electrical connection means is configured to be connected to a source of extra low voltage electrical power. It will be appreciated that any preferred connection means can be used including 'automatic' connection means wherein a connector(s) extends from the lamps module 20 and is 30 connected to a corresponding connector when the sealed lamp module 20 is disposed in the lamp housings 10. Fig. 2 shows the rear view of the traffic signal lantern housing 1. In this view, an electrical cable conduit 22 can be seen disposed to the rear side 5 of the target board 6 3. Electrical cable (not illustrated) is passed through the conduit 22 via conduit aperture 23. The electrical cable then able to be connected to the electrical connection means of sealed lamp modules 20. It will be appreciated, however, that the conduit 22 in the configuration shown is optional and if provided may take any suitable form 5 so long as electrical power can be fed though to the seal lamp modules 20 when disposed in the lamps housings 10. In use, it can therefore be seen that the traffic signal lantern housing 1 can have lamp housings 10 or modules 20 replaced by a single worker on a ladder, for example, and 10 there is no need for additional lifting equipment. This is not possible with the prior art since the lantern housings are typically roll-formed and significantly heavier accordingly. Further, risk of electrocution from the traffic signal lantern housing 1 is significantly reduced firstly by using a low voltage power supply but also by the provision of the separate lamp housings and lamp modules that can be easily removed 15 and replaced by a single worker on a ladder carrying the replacement components. Since a sealed roll-formed type lantern housing is not used, a worker can carry an entire traffic signal lantern housing 1 up a ladder for replacement or installation. In other preferred embodiments (not illustrated), a single lamp housing 10 is provided. 20 In such an arrangement, the lamp modules 20 are removably mounted within the housing 10. Similarly, a single visor 17 for directing light from all three lamp modules may also be provided to be removably mounted to the lamp housing front 15. Also, the three lamp modules 20 may be replaced by a single lamp module having one or more LED light sources therein. 25 Although screws 11 have been described, it will be appreciated that the lamp housings can be bolted to the target board 3 or releasably engage each other by means of engagement slots and corresponding tabs. In this way, tools are not required to replace the housings 10. This is similarly the case with the target board 3 which may 30 be clipped to the frame 2 rather than use screws or bolts. Of course, any preferred fastening means can be used and the lamps housings 10 may be hingedly mounted. The traffic signal lantern housing 1 has a significantly reduced weight over the prior art as the single environmentally sealed lantern housing is not required. The reduction 7 * J13'Hl-lU-L)1 in total component numbers in constructing the traffic signal lantern housing 1 provides a decrease in cost and the ability to be used by a single worker increases operational efficiency. Further, the removal of the need for a single environmentally sealed lantern housing advantageously allows additional components or equipment 5 (for example, signs, electrical equipment, etc) to be mounted with or adjacent the traffic signal lantern housing 1 as significantly less space is required. The single environmentally sealed lantern housing no longer being required in the present invention means that only the lamp module(s) 20 is sealed from the weather making servicing easier and safer, especially during inclement weather. 10 Furthermore, it will be appreciated that all of the traffic signal lantern housing 1 components can be accessed from the front of the traffic signal lantern housing 1. In the embodiment shown in the drawings, the lamp modules 20 are each captively retained in separate housings 10 providing the significant benefit of single lamp 15 modules 20 being able to be held by a worker in one hand whilst ascending a ladder, for example. The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the art, can be made thereto without 20 departing from the scope of the present invention. The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "including" or "having" and not in the exclusive sense of "consisting only of'. 25 8