Patent Description:
At least in Australia, there are mandated laws that require lights to be used on bicycles when riding at night. A white light must be used on the front and a red light is to be used on the back. Each of these lights must be visible from <NUM> metres in front and behind, respectively. The main function of a bicycle light is to enable the rider to be seen by other road users, such as other cyclists, cars and pedestrians. For certain riding, a function of the front light is also to enable the cyclist to see ahead for obstacles.

Bicycle crashes most commonly occur at intersections and are more likely when the light is poor. Intersections can make it difficult to see bicycles, where the other road user is approaching the bicycle from their side, as many lights have a limited light beam angle.

The beam angle of a light is the angle at which light from the original source spreads or is distributed. This is typically measured from directly in front of the light source and generally can vary from <NUM> degrees to <NUM> degrees. Generally speaking, the higher the brightness of the light source, the narrower the beam angle. Conversely, a wider beam angle corresponds with lower brightness.

The beam angle can be altered with the use of lenses, which sit over the light source and refract or bend the light to widen the angle. However, such systems have limitations on how wide the beam can be widened.

The recent development of chip-on-board (COB) light emitting diode (LED) assemblies has allowed for very bright lights to be made in small housings. The reason for this is that the assembly can use a large number of LED chips on a substrate using a single circuit and only two contacts, reducing the componentry required. However, whilst the brightness can be increased by using COB LED assemblies, there is still a limitation on the beam angle. It is therefore a desired object to provide an alternative portable light that may be suitable for use on a bicycle.

Discussed in <CIT> is a visual recognition and identification apparatus comprising a mounting means that incorporates light emitting diodes connected to a printed circuit board and adapted to provide a visual signal.

Reference to any prior art in the specification is not an acknowledgment or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be understood, regarded as relevant, and/or combined with other pieces of prior art by a skilled person in the art.

According to a first aspect, there is provided a portable light, including:.

The collective beam angle is more preferably greater than <NUM> degrees.

The portable light may be a bicycle light. In such an embodiment, the rear surface of the housing may be curved to sit against a tubular frame member, such as the seat post or the head tube. Alternatively, the rear surface could be flat or slightly curved and the portable light may be used as a head torch. It will be appreciated that the present invention is not limited by the way in which the portable light is able to be used.

The rear surface may include means for mounting the light to an element. In one embodiment, the rear surface may include a mounting bracket configured to mount the light to the element. The mounting bracket may mount the light to the element by at least partially encircling the element. The mounting bracket may also include a mounting strap that at least partially encircles the element. The mounting strap may be removable or permanently attached to the housing and/or the mounting bracket. The mounting strap may be rigid or flexible. The mounting bracket and/or mounting strap may frictionally engage the element to secure the light to the element.

A USB connector may be integrated into the housing to enable charging of the battery. The USB connector may comprise a male USB connector or a female USB connector. The male USB connector may protrude from the housing. The female USB connector may be in the form of a port that extends into the housing. The USB connection may be in the form of a USB-A connector, USB-B connector, USB-C connector, mini-USB connector, micro-USB connector, or any other form of USB or charging connection.

The front lens cover is preferably curved to correspond to the curve of the front surface and COB assembly. The front lens cover may be clear or may be colour tinted. The front lens cover is intended to provide physical protection to the COB assembly and also a degree of waterproofing to the internal components. The direction of the light emission is provided by the orientation of the individual LED chips and not from any refraction caused by the front lens cover, although a minor amount of refraction by the lens covers will likely result.

The COB assembly substrate may be made from any suitable semi-conductive or thermally conducive material, for example aluminium, polymer, such as a composite-polymer, polyamide etc. The substrate may act as a heat sink. The substrate is preferably bendable, such that during manufacture the COB assembly may be bent to form the curved shape and is able to hold that shape after release. Alternatively, the substrate may be flexible and attached to the housing in order to hold the curved shape, or heat may be applied during the bending.

The COB assembly substrate will have a first surface, which may include a thermally conductive dielectric layer. A copper circuit layer may be printed on the dielectric layer. An insulative coating may then be applied over the first surface, keeping a matrix of copper pads exposed. The insulative coating may be white ceramic paint to reflect light outwards from the COB assembly first surface.

The LED chip may include a die connected to a copper pad with an electrically conductive adhesive, and a wire bond connecting the die to an adjacent copper pad. Alternatively, the LED chip may be a non-wire package, known as a flip chip package, whereby the electrical contacts are on the base of the chip and connect directly to the copper pad via solder. Further alternatively, the LED chip may be any other form of LED component, including a surface mounted (or SMT) LED chip, or any other fully encapsulated or self-contained LED component that is mounted to the substrate. A printed circuit board (PCB) may be electrically connected to the COB assembly at an edge of the COB assembly or via one or more openings, notches, or slots in the COB assembly.

For a white LED die, a yellow phosphor layer may be applied over the top of the first surface before the outer coating is applied. The outer coating may be a clear silicone layer; alternatively the silicone may be tinted. It will be appreciated that alternative suitable materials may be used for all components.

The curve direction is preferably perpendicular to the direction of the wire bond so that the wire does not bend. For example, when the portable light is in use in one embodiment, the wire bond may extend vertically and the curve extends around a horizontal sweep. The curve may be a parametric curve.

The physical bend extends about an angle of <NUM> degrees up to <NUM> degrees. More preferably, the bend extends between <NUM> degrees and <NUM> degrees, most preferably <NUM> degrees.

According to a second aspect, there is provided a portable light, including:.

The front lens cover may be mounted to the housing. The COB assembly may be mounted to the housing. The housing may include a curved surface that is similar in curvature to the COB assembly.

The portable light according to the second aspect may include any one or more of the features described above in relation to the portable light according to the first aspect.

According to a third aspect, there is provided a device for bending a chip-on-board (COB) assembly, including:.

According to a fourth aspect, there is provided a method of bending a chip-on-board (COB) assembly, the COB assembly having a substrate with a matrix of individual light emitting diodes (LED) chips mounted to a first surface, the method including:.

Advantageously, the movement of the actuators, the clamping device and the forming die follow a pre-defined sequence and timed movement.

The guide positions the COB assembly with opposing peripheral edges adjacent to the clamping devices, whereby the actuators are programmed to move inwardly a set distance whilst jaws of the clamping device are open to position the jaws on the first and second sides of the opposing edges, the jaws are then closed to clamp the COB assembly.

The COB assembly may then be released from the clamping device and transferred to another station that trims the opposing peripheral edges of the substrate.

In one embodiment, the COB assembly is a plurality of spaced apart COB assemblies, integrally formed from a single substrate sheet, whereby the trimming of the opposing peripheral edges separates the individual COB assemblies.

The method of bending ensures that the first surface of the COB assembly is not touched by the bending device.

An individual COB assembly may be assembled into the portable light of the first aspect of the invention.

Further aspects of the present invention and further embodiments of the aspects described in the preceding paragraphs will become apparent from the following description, given by way of example and with reference to the accompanying drawings.

<FIG> show a portable light <NUM> having a front <NUM>, a rear <NUM>, a top <NUM> and a bottom <NUM>, when used in an upright orientation. The light has a housing <NUM> and a lens cover <NUM> that has a curved surface running from side to side, with the surface being straight up and down.

The rear surface <NUM> of the housing is curved to sit against a tubular object, such as a bicycle frame. The rear surface also includes formations in the form of two spaced apart parallel slots <NUM> to allow for the connection of a mounting bracket, to be described below. The housing <NUM> also includes a USB connector <NUM> for charging the internal battery, and a button <NUM>. The button <NUM> can be used to turn the light on and off, and also to cycle between modes, such as flashing or constant.

As can be seen in <FIG>, a mounting bracket <NUM> can be removably connected to the rear surface <NUM>. The mounting bracket includes a silicone strap <NUM> that can be wrapped around a tubular frame. A mounting pad <NUM>, also made from silicone, can be adhered to the surface of the mounting bracket <NUM>. The mounting pad assists in protecting the tubular frame and provides friction to prevent the light from sliding.

<FIG> is a plan view of the light, which illustrates the curve of the front lens cover <NUM> and the corresponding curve of the front of the housing. The curve extends around an angle of <NUM> degrees and is parametric in shape. However, it will be appreciated that the present invention may be used with a bend greater or less than <NUM> degrees, generally in the range of <NUM> degrees to <NUM> degrees.

As shown in <FIG>, the light 10a may be provided in different sizes. Light 10a is the same as light <NUM> in all respects, except it is shorter.

<FIG> is an exploded view of the light assembly. The housing <NUM> is constructed from a rear body <NUM> and a front body <NUM>. When the two bodies are coupled together they create an internal space <NUM> for receiving a battery <NUM> and a printed circuit board (PCB) <NUM>. The rear body <NUM> includes the rear curved surface <NUM> with slots <NUM>. The mounting bracket <NUM> has two spaced apart rails <NUM> that slide into slots <NUM>. Embedded in an aperture in the rear surface <NUM> is a first magnet <NUM>. A second magnet <NUM> is embedded in an aperture in the mounting bracket <NUM>, such that when the mounting bracket is slid onto the rear surface, the two magnets engage to strengthen the connection, whilst making the mounting bracket readily removable.

<FIG> illustrates two alternative mounting pads <NUM>, 34a. Mounting pad 34a has a different rear profile to provide a smaller curved surface for fitting onto a smaller diameter tubular object.

The front body <NUM> has a front surface <NUM> that is curved in one direction, being sideways, corresponding to the curve of the front lens, as discussed above. Positioned between the front body <NUM> and the front lens cover <NUM> is a chip-on-board assembly <NUM>, which is shown in greater detail in <FIG>.

The chip-on-board assembly, commonly known as a COB assembly, includes a substrate <NUM> made from a semi-conductive material, for example aluminium or selective polymers. The substrate may be thermally conductive to act as a heat sink. Mounted to a first surface of the substrate is a matrix of light emitting diode (LED) chips <NUM>. The matrix of chips <NUM> are generally arranged in columns and rows, although this may be varied. The type of chips <NUM> may also vary. <FIG> show a wire bonded LED chip. The substrate <NUM> in this embodiment is aluminium, which has a thermally conductive dielectric layer <NUM> on the first surface. A copper circuit layer is then added over layer <NUM>. A solder mask layer <NUM> is then applied covering the majority of the surface, whilst leaving areas of the copper circuit layer exposed to form copper pads <NUM>. The solder mask layer <NUM> is preferably white ceramic paint. A die <NUM> is attached to a copper pad <NUM> using electrically conductive adhesive <NUM> and is then connected to another copper pad <NUM> using a wire bond <NUM>. The direction of all of the wire bonds <NUM> in a matrix are orientated to run in the same direction. This direction is vertical in this embodiment, allowing the COB assembly to be bent in the horizontal direction without breaking any of the wire bonds, which are highly fragile. Wire bonded LED chips are often used for red LEDs.

Another LED chip is shown in <FIG>, which is a white flip chip. In this embodiment, the substrate and layers are the same as the first embodiment it is only the LED chip that differs. The flip chip package <NUM> is bonded to the copper pads <NUM> by solder <NUM>. Similar to the wire bonded LED chips, the orientation is such that the flip chip packages <NUM> all run in the same direction, being perpendicular to the direction of bending.

Over the top of the LED chips is an outer coating <NUM> (shown in <FIG> only) of silicone to protect the assembly, although the LED chips are still quite fragile and pressure applied to them may cause damage.

Turning back to <FIG>, the bent COB assembly is placed over the curved front surface of the housing, providing support. Two leads (not shown) from the PCB extend through a gap in the front body <NUM> and are soldered to the two contacts on the edge of the COB assembly. The lens cover <NUM> is then placed over the front to enclose the light and provide protection to the COB assembly.

The curved COB assembly positions multiple LEDs about the curve so that they are orientated to direct light outwardly about the curve. The design means that individual LEDs are projecting a beam in a straight direction, in a sideways direction and at acute angles in between. The result of this is a collective beam angle of approximately <NUM> degrees. The increased beam angle created this way does not require an optic lens to bend the light, so the illumination remains bright. When the light is attached to a bicycle frame the visibility of a rider to other road users is greatly increased, as the light is clearly projecting sideways in both directions and at all angles in between.

The fragility of the LED chips means that bending the COB assembly without damaging any of the LED chips is complicated. A unique device and method has been developed to produce the curved COB assembly for use in the portable light.

The COB assembly is manufactured flat and has substrate salvage incorporated into two opposing peripheral edges <NUM> to assist in handling the assembly without contacting the components. <FIG> and <FIG> show a device for bending a COB assembly. It includes a guide <NUM> with two stepped spaced apart supports <NUM> with upwardly facing surfaces onto which the flat COB assembly can be placed. The guide is sized and shaped to position the COB assembly with its first surface upwards and its salvage edges <NUM> sideways.

Two opposing clamping devices <NUM> are positioned to either side of the guide <NUM>. The clamping devices <NUM> include one or more jaws <NUM> that clamp onto the salvage edges <NUM>. The clamping devices are pivotally attached to the end of horizontal linear actuators <NUM> via rotation pins <NUM>.

Below the guide <NUM> and COB assembly <NUM> is a forming die <NUM> (see <FIG>) attached to the end of a vertical linear actuator <NUM>. The forming die <NUM> has a curved engagement surface <NUM> that comes into contact with the second side of the COB assembly when raised. The curved engagement surface corresponds to the desired curve for the portable light.

In operation, a flat COB assembly <NUM> is placed onto the guide <NUM> and the actuators <NUM> are programmed to move inwards slightly to position the open jaws <NUM> over the salvage edges <NUM>. The jaws then shut, clamping the edges. The vertical actuator <NUM> pushes the forming die <NUM> upwards into the second side of the COB assembly, bending the substrate from the centre. To allow the substrate to bend, the horizontal actuators <NUM> also move inwardly as the substrate bends and the clamping devices <NUM> are able to freely rotate to follow the bending. This movement is illustrated in <FIG> and <FIG>. The movement of the actuators may all be pre-programmed to ensure correct tension is maintained during bending.

As can be seen in <FIG>, the jaws <NUM> are clamped onto the salvage edges <NUM> of the flat COB assembly. As the forming die presses against the centre of the substrate, the substrate starts to bend upwardly. To allow the bending, the edges need to move inwardly and rotate, as successively shown in <FIG> and <FIG>.

Following the bending process, the COB assembly is released from the jaws <NUM> and removed from the device. The salvage edges <NUM> are then trimmed off.

The device and bending process is suitable for forming individual COB assemblies. However, it can also be adapted to bend multiple COB assemblies simultaneously. As shown in <FIG>, multiple COB assemblies can be made using an integral substrate, whereby they are joined together by common salvage edges <NUM>. After the bending process is completed, the salvage edges <NUM> can be sliced off along lines <NUM>.

Claim 1:
A portable light (<NUM>), including:
a housing (<NUM>) having a front surface (<NUM>), a rear surface (<NUM>), and an internal space (<NUM>) for receiving electronic components and a battery (<NUM>);
a chip-on-board (COB) assembly (<NUM>), including:
a substrate (<NUM>), a matrix of individual light emitting diode (LED) chips (<NUM>) mounted to the substrate (<NUM>), and an outer coating (<NUM>) covering the matrix of LED chips (<NUM>);
wherein the front surface (<NUM>) is curved in one direction and the COB assembly (<NUM>) is correspondingly curved and mounted to the front surface (<NUM>), such that individual LED chips (<NUM>) are positioned about the curve and orientated to direct light outwardly about the curve to provide a collective beam angle greater than <NUM> degrees; and
a front lens cover (<NUM>) to protect the COB assembly (<NUM>).