Technical Field

[0001] The present invention relates to fuses for modified fluorescent luminaires. In particular, the present invention relates to fuses for fluorescent luminaires that have been modified for use with LED lube lights.

Background Art

[0002] LED lube lights are becoming common and offer a number of advantages over traditional fluorescent tube lights. For example, when compared with fluorescent lights, LED lube lights are more energy efficient, contain less toxic materials (especially mercury), are dimmablc, and do not burn out if they arc turned on and off numerous times. For these reasons, many people are choosing to upgrade their existing fluorescent luminaires so that they can use LED tube lights.

[0003] Modifying a fluorescent luminaire so that it can use LED tube lights may be achieved in a number of ways. For example, the fluorescent luminaire may be modified for use with LED tube lights by being re-wired (by a qualified electrician) to suit (he LED lubes, with a purpose designed LED fuse being inserted into the circuit for each tube replaced.

[0004] Such modified luminaires are, however, no longer suitable for use with fluorescent tubes. In normal use, should a person try to replace the LED tube with a traditional fluorescent tube (e.g. in case of a malfunctioning light requiring temporary replacement), the LED fuse would 'pop' as a normal fuse would to prevent electrical shock across the entire luminaire. However, if the user was to remove the LED fuse (notwithstanding the presence of warning stickers as required by the relevant wiring Standards or Regulations) and replace the LED tube with a traditional fluorescent tube, the luminaire may become electrically live and present a serious health and fire hazard to the user and the properly.

[0005] II would be advantageous to diminish the risk of such modified luminaires inadvertently becoming electrically live. Summary of Invention

[0006] The present invention provides a ruse for a fluorescent luminairc that has been modified for a LED lube light. The fuse comprises terminals adapted to make electrical contact with a circuit via which electricity is supplied to the luminaire, and a lock for hindering removal of the fuse from the luminaire. The fuse is adapted to break the circuit if a fluorescent tube is used with the luminaire.

[0007] The lock that hinders removal of the fuse from the luminaire of the present invention provides an additional warning to a user who may be considering removing the fuse in an attempt to make the modified luminaire work with a fluorescent tube. It is hoped that such a tactile warning would prompt the user to reconsider what they were doing, and perhaps read some of the warning notices on the modified luminaire. Thus, use of the fuse of the present invention can substantially reduce the likelihood of a user inadvertently causing the modified luminairc from becoming electrically live, thereby reducing all the potential consequences of doing so.

[0008] In the event that it is actually necessary to remove the fuse from the luminaire of the present invention (e.g. a qualified electrician needs to perform some work on the luminaire or the fuse has blown), then the lock can be actuated and the fuse removed.

[0009] In some embodiments, the lock substantially prevents removal of the fuse from the luminaire. Thus, a user simply would not be able to remove the fuse (and its attendant safety functions) from the luminaire without actuating the lock.

[0010] In some embodiments, the removal of Uie fuse from the luminaire requires a separate tool. This requirement presents yet another prompt to the user to reconsider whether removing the fuse is appropriate.

[001 1] In some embodiments, the lock is actuatable between an unlocked position, where the fuse is removable from the luminaire, and a locked position, where removal of the fuse from the luminaire is hindered. For example, in some embodiments, the lock may comprise a screw which is screwable lo actuate the lock between the unlocked position and the locked position, and vice versa, in the locked position, an end of the screw in a fuse installed in a modified luminaire may engage (e.g. abut) a surface of the modified luminaire (i.e. the screw may only hinder removal of the fuse). Alternatively, in the locked position, an end portion of the screw is receivable within an aperture or threadingly engageable with a threaded bore in the modified luminaire (e.g. the fuse could not be removed without unscrewing the screw). [0012] In some embodiments, the terminals arc adapted for receipt in a fitting of the luminairc which previously received a fluorescent light starter. In such embodiments, the fuse is very easily useable in the modified luminairc because the fitting (usually a GU-IO socket) for the fuse is already present. Providing a fuse that is simple to install can promote widespread acceptance and use of the fuse.

[0013] In some embodiments, the fuse is contained in a cylindrically shaped body (i.e. like a fluorescent light starter). In some embodiments, the cylindrically shaped body may have a longitudinal depression, with the lock being at one end thereof. The longitudinal depression may, for example, be adapted to receive a tool (e.g. a screwdriver). Thus, the lock is readily accessible to an appropriately qualified user.

Brief Description of Drawings

[0014] A specific embodiment of the present invention will now be described, by way of example only, with reference to the following drawings, in which:

[0015] Figure 1 shows a top view of a fuse in accordance with an embodiment of the present invention in an unlocked (A) and locked (B) configuration;

[0016] Figure 2 shows a side view of the fuse of Figure I in an unlocked (A) and locked (B) configuration;

[0017] Figure 3 shows a front end view of the fuse of Figure 1 in an unlocked (A) and locked (B) configuration;

[0018] Figure 4 shows a bottom view of (he fuse of Figure 1 in an unlocked (A) and locked (B) configuration;

[0019] Figure 5 shows a back end view of the fuse of Figure 1 in an unlocked (A) and locked (B) configuration;

[0020] Figure 6 shows a perspective view of the fuse of Figure 1 and a socket which would be present in a modified fluorescent luminaire; and

[0021] Figures 7 A, 7B and 7C show the fuse of Figure 1 being inserted into and locked to the socket of Figure 6. Description of Embodiments

[0022] The present invention provides a ruse for a fluorescent luminairc that has been modified for a LED lube light. The fuse comprises terminals adapted to make electrical contact with a circuit via which electricity is supplied to the luminaire, and a lock that hinders removal of the fuse from the luminaire (i.e. post-installation). The fuse is adapted to break the circuit if a fluorescent tube is used with the modified luminaire.

[0023] The fuse of the present invention may be used with any indoor or outdoor fluorescent luminaire that has been modified (e.g. by wiring) for use with a LED tube light. Such modification will depend on the type of fluorescent luminaire being modified but, in general, will involve rewiring to electrically bypass the ballast, removing the capacitor and replacing the starter with a LED fuse. As discussed above, once fluorescent luminaires have been modified for use wilh LED tube lights, (hey are no longer suitable for use with fluorescent lights and it can be very dangerous if an unqualified person attempts to rc-install a fluorescent tube and attempts to make it work.

[0024] The fuse may be any suitable electrical switch which, under the conditions that would be experienced should a person insert a fluorescent tube into the modified luminaire, would react to break the electrical circuit to prevent short circuiting and possible electrical shock.

[0025] In some embodiments, the fuse may be a high rupturing capacity (HRC) type fuse (e.g. for use in Australia where mains electricity is about 240V). However, other types of fuses could also be used, including time delay fuses, self-resetting fuses, resectable (PPTC) type fuses, blade fuses, glass tubc bosch type fuses and screw type fuses. In some embodiments, the fuse may be provided in the form of a circuit breaker. The choice of fuse will depend on the specific conditions under which the modified luminairc is to be operated (e.g. supplied current and voltage, wattage of (be LED lube light, space restrictions, etc.), and it is within the ability of persons skilled in the art to determine a suitable fuse for a given luminaire.

[0026] The fuse of the present invention has terminals adapted to make electrical contact with a circuit via which electricity is supplied to the luminaire. Any suitable terminals may be used, but in many cases it may be preferable lo use terminals that can be used wilh the luminaire without necessarily requiring additional connections or sockets to be installed (i.e. to make the re-wiring job as simple as possible). As would be appreciated, this would simplify the re-wiring process and promote widespread acceptance and use of such fuses.

[0027] For example, in some embodiments, the terminals may be adapted for receipt in a fitting of the luminairc which previously received a fluorescent light starter. In the majority of fluorescent luminaires, a standard fitting known in the industry as GUIO sockets is used for this purpose, and it may therefore be advantageous to provide the fuse of the present invention with terminals adapted to be connected to a GUI 0 socket. It is to be appreciated, however, that not all fluorescent luminaires have such fittings (e.g. some fluorescent luminaires do not require starters and would not therefore have such fittings). In such situations, part of the process of modifying the fluorescent luminaire would involve adding a socket for receiving a LED fuse (either of the present invention or otherwise).

[0028] The fuse of the present invention also has a lock that hinders removal of (he fuse from the luminaire. As discussed above, by hindering removal of the fuse, the lock is effectively a second tier locking mechanism which provides a tactile warning to a user who may be considering removing the fuse in an attempt to make the modified luminaire work with a fluorescent tube. It is hoped that the user will be more cautious about replacing LED tubes with fluorescent tubes when the fuse of the present invention is used.

[0029] Whilst not absolutely necessary, it may be safer in some cases if the lock substantially prevents removal of the fuse from the luminaire. If so, it will not generally be possible for a person to remove the ruse without unlocking it, which is likely to promote an even more thorough consideration on the behalf of the user regarding exactly what they are doing.

[0030] Any suitable mechanism may be used to hinder removal of the fuse from the modified luminaire. Examples of such mechanisms include mechanisms which work via an interference or frictional fit, sliding mechanisms, screw mechanisms, squeeze mechanisms, etc. Mechanisms that work using friction or via abutting parts may be more appropriate for locks that hinder removal of the fuse from the luminaire. Mechanisms that work using parts that slide or are screwed with respect to each other may be more appropriate for locks that substantially prevent removal of the fuse from the luminaire.

[0031 ] In some embodiments, removal of the fuse from the luminaire may require the use of a separate tool. However, in alternate embodiments, the fuse is removable from the luminaire without a tool. For example, a lock in the form of a squeeze mechanism not dissimilar to that on the caps of child-proof containers could be employed, where a relatively strong squeezing force needs to be applied in order for the fuse to be removed.

[0032] In embodiments where removal of the fuse from the luminaire requires the use of a separate tool, any suitable tool may be used. However, it may be better if the user is caused to make some sort of an effort in order to procure the tool. For example, if a user tries to remove the fuse in order to make an installed fluorescent light work, but is not able, they are more likely to have a closer look at the fuse and luminairc in general in an effort to ascertain how to remove the fuse. During the course of such an investigation, they would be more likely to notice the safety warnings and hopefully consider the consequences of installing the fluorescent light.

[0033] Examples of tools suitable for use with the present invention include screwdrivers (e.g. flat or Philips head), Allen keys (with standard or custom heads), spanners, etc.

[0034] In use, the lock is typically actuatablc between an unlocked position where the fuse is removable from (he luminaire, and a locked position where removal of the fuse from the luminaire is hindered. The lock may be actuated between unlocked and locked positions (and vice versa) using any of the mechanisms described above.

[0035] For example, in some embodiments, die lock comprises a screw and the lock is actuated by screwing the screw between the unlocked position (i.e. when the screw has been unscrewed) and the locked position (i.e. when the screw has been screwed in), and vice versa. In some embodiments, an end of the screw engages (e.g. abuts) a surface of the modified luminaire when in the locked position. The surface may be a relatively flat surface, or may have a small indent or the like to receive the tip of the screw. Such embodiments may hinder, but not prevent, removal of the fuse from the luminaire. In alternate embodiments, an end portion of the screw can thrcadingly engage a threaded bore in the modified luminairc when in the locked position, or be received into an aperture in the modified luminaire (e.g. an aperture in a socket of (he luminairc). Such embodiments would substantially prevent removal of the fuse from the luminaire.

[0036] The use of the present invention may have any shape, but is typically shaped such that it can be used with the modified luminaire without requiring additional modifications (i.e. other than the re-wiring). As would be appreciated, this would simplify the luminairc modification process and further promote widespread acceptance and use of such fuses.

[0037] In some embodiments, the fuse is contained in a cylindrically shaped body such that it has an appearance similar to a fluorescent light starter. Often, the sockets for such starters are inside a casing of the luminaire, and providing the ruse with a similar size and shape as a starter enables the fuse lo be easily inserted into the socket.

[0038] In some embodiments, the shape of the fuse may be modified to enable access to the lock. For example, the fuse (e.g. the cylindrical fuse described above) may have a longitudinal depression, with the lock at one end thereof. The longitudinal depression may be adapted to receive a tool (e.g. a screwdriver). Thus, in such embodiments, the fuse can be easily inserted into the circuit of the luminairc, with the lock being accessible to a qualified (or informed) user to lock or unlock.

[0039] A specific form of the fuse of the present invention will now be described with reference to the accompanying drawings. Referring generally to the drawings, a specific form of the fuse of the present invention is shown in the form of fuse 10. Fuse 10 has a generally cylindrically shaped body 12 with two terminals 14, 14, shaped to be received in a GU 10 socket (the industry standard socket for starters for fluorescent luminaires, see Figure 6). Although not shown, inside the body 12 is a high rupturing capacity type fuse which is electrically connected to the terminals 1 , 14.

[0040] Body 12 has a recess 16, which extends for the majority of the length of body 12 between back end 18 and wall 20. Wall 20 has a threaded aperture therethrough, with a Philips head screw 22 in it. Screw 22 can be screwed between an unlocked position (shown generally in the A Figures) and a locked position (shown generally in the B Figures). In the locked position, an end 24 of the screw projects out from (he body 12 by approximately the same distance as the terminals 14.

[0041] Referring now to Figure 6, the fuse 10 is shown adjacent to a socket 30. Socket 30 is a GU10 socket, of the type well known in the art. Briefly, socket 30 has two arcuate key-hole shaped grooves 32, 32 which are adapted to receive and retain terminals 14 (herein. Each groove 32 has a relatively larger portion 34 at one end and a narrower portion 36 elsewhere.

[0042] Referring now to Figure 7, when fitting fuse 10 to socket 30, the terminal 14, 14 are first aligned with portions 34, 34 and the use then pushed towards socket 30 (as can be seen in Figure 7A). The larger head of each terminal 14 passes through portion 34, where they can make electrical contact with conductive material in the socket 30 (not shown) to thereby electrically incorporate the fuse 10 into whatever circuit the socket 30 may be part of.

Anticlockwise rotation (in this embodiment) of the fuse 10 with respect to the socket 30 (compare Figures 7A and 7B) causes the terminals 14, 14 to rotate in grooves 32, 32 away from portions 34, 34 and into the narrower portions 36, 36, where the fuse 10 becomes locked into the socket 30.

[0043] Once in the position shown in Figures 7B and 7C, the screw 22 becomes aligned with the portion 34 of one of the grooves 32. Thus, when the screw is screwed into the rase 10 (see Figure 7C), its end portion protrudes from the fuse 10 (e.g. compare Figures 1 A and IB), and extends into the socket via portion 34. As will be appreciated, once the end portion of the screw extends into portion 34, it will not be possible to twist the fuse 10 in a clockwise direction in order to separate it from the socket 30. Thus, the screw provides a secondary locking mechanism which binders (or substantially prevents) removal of the fuse 10 from the socket 30 (and hence the luminairc (not shown) with which the socket is associated).

[0044] By way of illustration, a benefit of using ruses in accordance with a specific embodiment of the invention (e.g. fuse 10) over standard LED fuses is given below.

[0045] School A has commissioned Company B to upgrade their existing fluorescent luminaircs so they can replace their florescent lubes with LED tubes. Company B completes the installation of the LED tubes by rewiring the existing fittings to suit LED tubes and using a standard LED fuse (i.e. not in accordance with the present invention) in place of the starter for each fluorescent tube replaced. Although Company B has used warning stickers as required by the relevant wiring Standards, users at School A post-install could possibly still attempt to replace the new LED lubes with a traditional fluorescent tube (in case of a malfunctioning light requiring temporary replacement or any other reason). If this is done and switched on whilst the LED fuse is in the fittings socket, the fuse would 'pop' (as a normal fuse would) to prevent electrical shock across the entire fitting. However, if the user were to replace the LED fuse with a starter and put in a traditional fluorescent tube, the fitting entirely would receive an electrical shock causing a serious health and fire hazard to the user and the property.

[0046] In a similar scenario, however, if Company B had fitted a fuse in accordance with a specific embodiment of the invention (e.g. fuse 10), the fuse can be 'dead-locked' to the luminaire socket/fuse holder to ensure that a user thinks twice before removing the fuse 10, and especially so as a tool is required to unlock the fuse 10.

[0047] Although standard LED fuses have protective attributes, they lack any security functionality. In order to be practical and ensure widespread use, any such functionality should ideally be provided whilst ensuring that the new fuse is relatively simple to install, for example by fitting within existing ruse sockets/starter holders. Specific embodiments of the present invention can provide a number of advantages over current LED fuses. For example, embodiments of the present invention can provide advantages including:

• the 'dead-lock' functionality provides simple and effective post-installation protection for a luminaires modified to accommodate LED tubes;

• the use can utilise existing fuse sockets/starter holders and is therefore easily rctrofitablc into practically any suitable luminaire; and • even though its removal is hindered, the fuse can be easily replaced in the event of damage.

[0048] It will he understood to persons skilled in the art of the invention that many modifications may be made without departing from the spirit and scope of the invention.

[0049] It is to be understood that any prior art publication referred to herein docs not constitute an admission that the publication forms part of the common general knowledge in the art.

[0050] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.