AU2015100128A4 - Rear access retrofit kit for railway signal lamps - Google Patents

Abstract

A retrofit kit to upgrade obsolete incandescent railway signal lamps with LED light modules which can be replaced and serviced via the rear maintenance apertures of existing signal lamp housings.

Description

REAR ACCESS RETROFIT KIT FOR RAILWAY SIGNAL LAMPS FIELD OF THE INVENTION The invention relates to a novel and innovative retrofit kit to upgrade obsolete incandescent railway signal lamps with LED light modules which can be replaced and serviced via the rear maintenance apertures of existing signal lamp housings. BACKGROUND OF THE INVENTION Prior art railway signal lamps are usually lit by incandescent light means. Most signal lamp housings provided access to maintenance from the rear of the box where there was often a simple ladder permanently installed. There is a current move to replace existing signal lamps with modern more durable and reliable LED light units. While the majority of suppliers would prefer to replace the entire lamp assemblies, there has been a development in the provision of less expensive LED light module conversion units. In most cases, the conversions to LED involve the replacement of the incandescent lamps through the front panels of the signal housings. Importantly, this step introduces a significant change in work practices as it means that all future maintenance or light module replacement has to be carried out using ladders or elevated work platforms via the front of the lamp. As previously mentioned, most prior art railway signals have permanent ladders attached to the back of the signal housing to allow for rearward access. There is therefore a benefit in a LED retrofit kit which is converted and maintained through the rear of the housing using the existing access and ladder means. It is therefore a general object of the present invention to seek to eliminate or ameliorate the disadvantages and limitations of the prior art. It is however a specific objective to provide a novel and inventive LED conversion kit which uses the already existing rear maintenance access means of railway signal lamps. 1 SUMMARY OF THE INVENTION In one aspect, the invention resides in a retrofit kit for converting incandescent railway signal lamps to LED light modules including: an adaptor insert to fit an existing signal lamp housing; the insert adapted to pass through the front of the housing to provide an rearward facing circumferential mounting surface to engage a raised peripheral ledge of an LED light module installed via an existing rear access aperture of the signal lamp housing; the insert further including two or more spaced holes for bolts to engage and pass through threaded holes in the housing to secure the insert to the housing; two or more clamping clips associated with the bolts; the clips adapted to clamp the peripheral ledge to the mounting surface by one or more nuts tightened on the free ends of the bolts. Preferably, a portion of the insert extends outwardly and sits proud of the lamp housing to support an external lamp hood. Preferably, a moisture proof gasket is installed between the mounting surface and the contacting face of the peripheral ledge. Preferably, anti-seizing compound is used on the nuts and bolts and any parts or surfaces prone to corrosion. In another aspect, the invention resides in a method of using a retrofit kit for converting incandescent railway signal lamps to LED light modules according to any of the above claims including the steps of: accessing the rear maintenance aperture of the signal lamp housing; removing the existing incandescent lamp from the lamp housing; 2 ensuring that the holes of a gasket align with the threaded holes of the signal housing; ( and rethreading any of the threaded holes of the housing if necessary;) fitting the insert and gasket to the housing with the bolts passing through the threaded holes; (applying at any stage, anti-seizing compound on the nuts and bolts and any parts or surfaces prone to corrosion as recommended;) fitting the lamp hood to the insert by bolts or screws or other means; installing the LED light module via the rear maintenance aperture; ensuring that the module is centrally located and that the peripheral ledge is seated against the circumferential mounting surface; fitting the clips to the free ends of the bolts; hand tightening nuts on the bolts to clamp the light module to the insert, and wherein the steps shown in brackets are to be considered optional or recommended steps as is required. BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention be understood, reference is made to the accompanying drawings wherein: FIG. 1 shows an exploded view of a preferred retrofit kit and LED light module according to the invention. FIG. 2 shows detail of the insert of FIG. 1, and FIG. 3 shows the assembled retrofit kit of the invention. DETAILED DESCRIPTION OF THE EMBODIMENT. As shown in FIG. 1 the preferred retrofit kit for converting incandescent railway signal lamps to LED light modules includes an adaptor insert 10 specially adapted to fit an existing signal lamp housing 12. The insert has an inward circumferential mounting surface 10a to engage a raised peripheral ledge 14a of an LED light module 14. The module is installed via an existing rearward access aperture of the signal lamp housing (not shown) .The insert includes spaced holes 10b-10e for bolts 16,18,20,22 to pass 3 through the insert into threaded holes 24,26,28 in the housing. Clamping clips 30, 32, 34 associated with the bolts clamp the peripheral ledge to the mounting surface 10a by nuts 36, 38, 40 and associated washers 42, 44, 46 tightened on the free ends of the bolts. A portion of the insert 10 extends outwardly and sits proud of the lamp housing 12 to support an external lamp hood 48. A moisture proof gasket 50 is installed between the contacting surfaces of the inward face 10a and the ledge 14a of LED light module 14. Preferably, anti-seizing compound is used on the nuts and bolts and any parts or surfaces prone to corrosion. FIG. 2 shows detail of the front of the insert 10 including the spaced holes 10b-10e for bolts to pass through the insert into threaded holes in the housing (both not shown). There are holes 10f, 10g for screws for fitting the hood (not shown). FIG. 3 shows the assembled retrofit kit with the light module 14 secured in the housing 12 by the insert 10 which also supports the hood 48. Advantages of the present invention include the overriding benefit of being able to service the replacement light module from the rear of the signal lamp housing via its existing maintenance panel. Existing rear ladders can also be retained and used without the added costs of front access equipment. The invention provides a more cost effective solution to upgrading existing railway signal lamps with new light modules than replacing the entire signal housing. There is also the advantage that there is no requirement for machinery or plant onsite to make the upgrades. 4 It will of course be realized that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein set forth. In the specification the terms "comprising" and "containing" shall be understood to have a broad meaning similar to the term "including" and will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the terms "comprising" and "containing" such as "comprise", "comprises", "contain" and "contains". 5

Claims (6)

1. A retrofit kit for converting incandescent railway signal lamps to LED light modules including: an adaptor insert to fit an existing signal lamp housing; the insert adapted to pass through the front of the housing to provide an rearward facing circumferential mounting surface to engage a raised peripheral ledge of an LED light module installed via an existing rear access aperture of the signal lamp housing; the insert further including two or more spaced holes for bolts to engage and pass through threaded holes in the housing to secure the insert to the housing; two or more clamping clips associated with the bolts; the clips adapted to clamp the peripheral ledge to the mounting surface by one or more nuts tightened on the free ends of the bolts.

2. The retrofit kit of claim 1, wherein a portion of the insert extends outwardly and sits proud of the lamp housing to support an external lamp hood.

3. The retrofit kit of claim 1, wherein a moisture proof gasket is installed between the mounting surface and the contacting face of the peripheral ledge.

4. The retrofit kit of claim 1, wherein anti-seizing compound is used on the nuts and bolts and any parts or surfaces prone to corrosion.

5. A method of using a retrofit kit for converting incandescent railway signal lamps to

6 LED light modules according to any of the above claims including the steps of: accessing the rear maintenance aperture of the signal lamp housing; removing the existing incandescent lamp from the lamp housing; ensuring that the holes of a gasket align with the threaded holes of the signal housing; ( and rethreading any of the threaded holes of the housing if necessary;) fitting the insert and gasket to the housing with the bolts passing through the threaded holes; (applying at any stage, anti-seizing compound on the nuts and bolts and any parts or surfaces prone to corrosion as recommended;) fitting the lamp hood to the insert by bolts or screws or other means; installing the LED light module via the rear maintenance aperture; ensuring that the module is centrally located and that the peripheral ledge is seated against the circumferential mounting surface; fitting the clips to the free ends of the bolts; hand tightening nuts on the bolts to clamp the light module to the insert, and wherein the steps shown in brackets are to be considered optional or recommended steps as is required. 7