Patent Application
20210164645
The present invention relates to a lighting and speaker device, and also to an annular LED assembly for use in a lighting and speaker device.
An object of the present invention is to provide an improved integrated speaker and downlight (combined lighting and speaker device) for flush mount ceiling installation.
Desirably, a combined lighting and speaker “smart light” device according to the present invention should provide a replacement for regular light fittings installed in the home. For example, devices according to the present invention may be installed to replace GU10 downlight fittings. In order to replace such fittings easily, it is desirable that the devices have a similar size to the fitting that it replaces. In some cases an increase in size of around 5% is acceptable.
Preferably, the combined lighting and speaker device should emit at least 700 Lumens. This is so that the smart light devices produce equivalent or better illumination than standard halogen bulbs.
The speaker arrangement of the combined lighting and speaker device should have similar acoustic properties to commercially available mono point speakers. Such as SoundTouch 10™, Bose™ and Sonos Playl™.
Combined Lighting and Loudspeaker Devices According to Earlier Embodiments not in Accordance with the Present Invention
A number of different embodiments were developed to address this above-mentioned objective. In a first particular example, a device includes a single full range speaker. Such a speaker should be capable of delivering good reproduction of high frequency (HF) and low frequency (LF) input signals.
Light emitting diodes (LEDs) are integrated into the device by removing the dust cap of the speaker and mounting a small number (for example, 1 to 6) High output LEDs on a stem that runs through voice coil former and seats on the pole piece.
High lumen output LED's are intrinsically less efficient compared to lower output LED packages, therefore, for every watt of power put in they will produce more watts of waste heat.
Excessive heating of LEDs can significantly shorten the life span of the LEDs or cause them stop working. To manage the waste heat in this embodiment, it is therefore necessary to run a condensing heat pipe from the LED stem through the pole piece of the drive and out to a heatsink at the back of the case.
Systems including a single full range drive unit, as described above, have drawbacks in terms of the quality of the sound that is produced.
In order to address these drawbacks, a separate tweeter may be added to the assembly and integrated with the speaker. In speaker systems not containing LEDs, there are two possible approaches to integrating a tweeter coaxially within a drive unit.
Type 1 is shown in
Type 2 is shown in
Both designs suffer from air leak round the voice coil air gap which reduces LF performance. They require a second roll surround 314 between voice coil former and chassis, below the suspension, or sealed suspension.
For either of the coaxially integrated tweeter arrangements described above, the heat path through the centre of the voice coil is no longer available because the tweeter is in the way. Thus a new approach to LED integration is required.
In accordance with a first aspect of the present invention, a combined lighting and speaker device is provided. The device has a central longitudinal axis defining a forward and a rearward direction and a radially outward and a radially inward direction. The device comprises a tweeter, a tweeter horn positioned radially outwardly of the tweeter, a speaker positioned rearward of the tweeter horn, and a light emitting diode, LED, assembly. The LED assembly is positioned radially outwardly of the tweeter. The LED assembly comprises one or more light emitting diodes, LEDs, and a lens having a forward surface. The tweeter horn has an inner edge in communication with an outer edge of the tweeter, so that the tweeter horn forms a guide to direct sound produced by the tweeter away from the speaker when in use. At least part of the tweeter horn is provided by the forward surface of the lens.
The speaker may be used to provide low frequency range sounds and the tweeter may be used to provide higher frequency range sounds. Advantageously, the sound quality is improved over full range single speaker devices by providing separate speaker and tweeter components for LF and HF sound ranges respectively.
By providing a tweeter cone, HF sound from the tweeter may be directed away from the LF speaker. Advantageously, interference of the HF sound with the LF speaker is reduced by the presence of the horn. The lens may be configured such that the light is a lambertian source or directed as a spot. In conjunction with this, fresnel features on the lens could be used to direct the spot by rotating the lens, rather than changing the angle of the light source itself.
Lighting may be integrated into the device by providing an LED assembly wherein the lens of the LED assembly forms part of the tweeter horn. This provides a compact solution with high quality light and sound in a single device.
The tweeter horn may comprise a cup part and an inner edge of the cup part may be in communication with an outer edge of the forward surface of the lens. The cup part may be positioned radially outwardly of the lens.
Alternatively, the lens of the LED assembly may provide substantially all of the tweeter horn, without the need for an additional cup part.
The tweeter horn may comprise a rim part having an inner edge that is in communication with the outer edge of the cup part. An outer edge of the rim part may comprise one or more notches through which sound from the speaker can travel when in use. The tweeter horn may be positioned radially outwardly of the cup part.
By providing a tweeter horn with a “feathered” rim, the overall sound quality may be improved by allowing sound from the LF speaker to travel through the notches in the tweeter horn, whilst still providing a tweeter horn capable of directing the HF sound away from the LF speaker.
The cup and the rim of the tweeter horn may be formed from a single piece of material.
The one or more LEDs may be mounted rearward of the lens (in a “horizontal” manner—i.e. facing forwards) so that light is emitted by each of the LEDs in a generally forward direction towards the lens when in use.
The LED assembly may further comprise a reflector configured to reflect light from the LEDs towards the lens when in use. In other words, the reflector may direct light from the LEDs in a forward direction. The reflector may be positioned rearward of the lens.
The one or more LEDs may be mounted so that light is emitted by each of the LEDs in a generally inward direction towards the reflector. The LEDs may be mounted radially outwardly of the reflector in a “vertical” manner.
Alternatively, the LEDs may be mounted in a “vertical” manner so that light from the LEDs is emitted in a generally outward direction towards the reflector. The reflector may be positioned radially outwardly of the LEDs and direct light forwards towards the lens.
The reflector may comprise one or more frustoconical surfaces. Alternatively, the surfaces may be frustopyramidal.
In the case of LEDs being mounted vertically and configured to direct light inwards, the reflector may be an outer frustoconical surface.
In the case of LEDs being mounted horizontally to direct light forwards, two reflectors may be provided—one inwardly of the LED ring and one outwardly. An outer furstoconical surface may be provided radially inwardly of the LEDs and an inner frustoconical surface may be provided radially outwardly of the LEDs. This configuration allows light from the LEDs to be directed forwards even if the light is emitted from the LED at an angle to the forward direction. This improves the amount of light from the LEDs that is directed into the room (e.g. through the lens) and improves the efficiency of the arrangement.
Additional reflectors may be placed between the LEDs in the ring to further increase the amount of light that is directed forwards into the room.
The reflector may comprise a plurality of individual reflector surfaces. These surfaces may be frustoconical or may be substantially planar (or a combination). This is illustrated in
The lens may be an annular lens. Alternatively, the lens may comprise a plurality of individual lenses, which may together form an annular lens arrangement.
An inner edge of the forward surface of the lens may be in communication with the outer edge of the tweeter. This can ensure that HF sound from the tweeter is directed into the horn (provided at least partially by the lens) and forwards, away from the tweeter and from the speaker.
Alternatively, the tweeter horn may further comprise a throat part. An inner edge of the throat part of the tweeter horn is may be in communication with the outer edge of the tweeter and an outer edge of the throat part may be in communication with an inner edge of the forward surface of lens. This alternative arrangement provides a separate throat to direct sound from the tweeter into the tweeter horn and allows improved control over the shape of the tweeter horn. Horns with an exponential profile may be preferred in some cases.
The tweeter horn may be frustoconical or frustopyramidal. Additionally or alternatively, specific components of the tweeter horn may be frustoconical or frustopyramidal. For example, one or more of the cup, the rim and the throat of the tweeter horn may be frustoconical or frustopyramidal. These may be inner frustoconical surfaces.
A carrier supporting the tweeter and the LED assembly may be provided. The carrier may be arranged to conduct heat from the one or more LEDs to tweeter horn. This can provide a way for heat from the LEDs to be dissipated. For example, the cup and/or the rim of the tweeter horn may conduct heat away from the LEDs and radiate the heat into the room. This may thereby dissipate heat produced by the LEDs when in use. This configuration may reduce the operating temperature of the LED and therefore improve the efficiency of the LEDs. This can also prevent or deduce damage to the LEDs caused by overheating.
The carrier may be supported by the tweeter horn. For example, the carrier may be mechanically fastened to the cup of the tweeter horn.
The tweeter horn and the carrier may be formed from a single piece of material. Advantageously, this can simplify construction and assembly and improve surface area for heat transfer from the LEDs. This also removes split lines from cosmetic surfaces.
The device may further comprise a chassis that supports the speaker.
The tweeter horn may be connected to and supported by the chassis. For example, the rim or cup of the tweeter horn may be mechanically fastened to and supported by the chassis.
The device may further comprise a support frame that is connected to and supported by the chassis. The support frame may support the tweeter horn and/or the carrier.
The device may further comprise: a controller supported by the chassis; and a plurality of wires configured to supply power and control signals from the controller to the tweeter and the one or more LEDs.
The wires may run along and be supported by the support frame (if present) or may run along and be supported by the tweeter horn. The wires may be in the form of a ribbon cable or may be formed by photo etched tracks on the tweeter horn.
In accordance with a second aspect of the present invention, an annular light emitting diode, LED, assembly for use in a combined lighting and speaker device comprising a tweeter is provided. The LED assembly has a central longitudinal axis defining a forward and a rearward direction and a radially outward and a radially inward direction. The LED assembly comprises one or more light emitting diodes, LEDs, arranged in a ring, an annular lens (or lens arrangement) and an annular reflector (or reflector arrangement) configured to reflect light from the LEDs towards the lens when in use. The reflector may be positioned rearward of the lens and configured to reflect light from the LEDs forwards.
This embodiment has particular advantages over prior art LED assemblies. The LED assembly of the present invention is more compact that previous assemblies. Moreover, the reflector may be used as colour mixing chamber to obtain a desired colour temperature.
The LEDs may be low power LEDs. Advantageously, a heat pipe may not be required to operate the LEDs of this assembly. This allows the LED assembly to be integrated into a combined light and loudspeaker device more flexibly.
The LED assembly according to the second aspect provides a compact and efficient solution for integrating LEDs into a combined light and speaker device.
The one or more LEDs may be mounted so that light is emitted by each of the LEDs in a generally inward direction towards the reflector. For example, the LEDs may be mounted radially outwardly of the reflector in a vertical manner so that light from the LEDs is emitted inwards towards the reflector and then directed forwards by the reflector towards the lens.
Alternatively, the LEDs may be mounted vertically so that light from the LEDs is emitted in a generally outward direction towards the reflector. The reflector may be positioned radially outwardly of the LEDs and direct light forwards towards the lens.
The reflector may comprise one or more frustoconical (or frustopyramidal) surfaces.
The one or more LEDs may comprise one or more LEDs having a first colour and one or more LEDs having a second colour different from the first colour.
The LEDs in the ring may be arranged so that each LED having the first colour is adjacent to an LED having the second colour.
The present invention also provides a combined lighting and speaker device having a central longitudinal axis defining a forward and a rearward direction and a radially outward and a radially inward direction. The combined lighting and speaker device comprises: a chassis; an annular light emitting diode, LED, assembly as described above; and a speaker supported by the chassis and positioned rearward of the assembly.
The combined lighting and speaker device may further comprise a tweeter positioned radially inwardly of the assembly.
The combined lighting and speaker device may further comprise a support frame that is connected to and supported by the chassis. The support frame may support the assembly.
The combined lighting and speaker device may further comprise a grille supported by the chassis and configured to support the assembly. The grille may be a pressed grille. Advantageously, the grille removes heat from the LEDs by conducting heat away from the LED assembly and radiating it into the room when the device is in use.
Electrically conductive tracks may be provided on the grille and configured to supply power to the assembly when in use.
Electrical contacts for the tracks may be provided in the frame.
The combined lighting and speaker device may further comprise a pole piece positioned at least partly along the central longitudinal axis and connected to and supported by the chassis. The pole piece may be configured to support the assembly.
The pole piece may be used to conduct heat away from the LED assembly. The heat may be conducted towards the chassis of the device or the thermal mass of the magnet steel.
In accordance with a third aspect of the present invention, a combined lighting and loudspeaker device having a central longitudinal axis defining a forward and a rearward direction and a radially outward and a radially inward direction is provided. The device comprises a lighting assembly; a speaker positioned rearward of the lighting assembly; and a power storage component. The power storage component is configured to supply power to the lighting and loudspeaker device when the lighting and loudspeaker device is not connected to a mains power supply.
The lighting assembly may be an LED assembly as described above.
The lighting assembly may be positioned radially inwardly of the speaker.
The combined lighting and loudspeaker device may further comprise a power storage component. The power storage component may be configured to supply power to the lighting and loudspeaker device when the lighting and loudspeaker device is not connected to a mains power supply.
The power storage component may be a rechargeable battery or a capacitor.
The power storage component is contained within a housing of the lighting and loudspeaker device.
The power storage component may be contained in a housing that is separate from a housing of the lighting and loudspeaker device and electrically connected to the speaker and the lighting assembly (an “umbilical” housing).
The present invention also provides a kit of parts that can be assembled to provide a device or assembly as described above.
The present invention also provides a method of manufacturing a device, assembly or kit of parts as described above.
According to the present invention, an assembly as described above may be used in a combined lighting and loudspeaker device.
Features and advantages described in relation to one aspect of the invention may also be applied to another aspect of the invention. For example, the LED assembly of the first aspect may comprise one or more LEDs having a first colour and one or more LEDs having a second colour different from the first colour, which may be arranged so that each LED having the first colour is adjacent to an LED having the second colour.
Other preferred features and advantages of the invention will be apparent from the appended claims.
The present invention also provides a combined lighting and speaker device having a central longitudinal axis defining a forward and a rearward direction and a radially outward and a radially inward direction. The combined lighting and speaker device comprises: a ring tweeter; a light emitting diode, LED, chip and lens assembly positioned radially inwardly of the ring tweeter; a tweeter horn positioned radially outwardly of the ring tweeter, a speaker positioned rearward of the tweeter horn. The tweeter horn has an inner edge in communication with an outer edge of the tweeter, so that the tweeter horn forms a guide to direct sound produced by the tweeter away from the speaker when in use.
As with the first embodiment, providing a tweeter cone directs HF sound from the tweeter away from the LF speaker. Advantageously, interference of the HF sound with the LF speaker is reduced by the presence of the horn.
The lens may be configured such that the light is a lambertian source or directed as a spot. In conjunction with this, fresnel features on the lens could be used to direct the spot by rotating the lens, rather than changing the angle of the light source itself. Alternatively, the lens may be a conventional lens. The lens may be configured so that the combined lighting and speaker device provides a more directional light source (for example, for task lighting).
The present invention may be put into practice in a number of ways, and some specific embodiments will now be described by way of example only and with reference to the following drawings.
The axes of the plots provided in
In order to obviate the need for a heat path through the centre of the voice coil, the present invention provides a larger numbers of high efficiency lower output LEDs which are collectively capable of similar lumen output but require minimal heat removal. In some examples, 8 or more LEDs are provided in the device.
According to embodiments of the present invention, a heat pipe through the centre of the voice coil is no longer needed. However, the high efficiency lower output LEDs still produce some heat, which needs to be dissipated in order to avoid damaging the LEDs. In some embodiments, a metal interface and small metal surface area are provided to remove heat.
The first example provides an integrated tweeter and a ring of LEDs suspended above the tweeter and supported on a sparse framework. HF interaction with the back of the LED ring may lead to unacceptable HF reproduction. As a result, this example is not preferred.
In this example, the tweeter is located on a stem with an annular arrangement of LEDs. One drawback associated with the second example, is undesirable interaction of the HF from the tweeter travelling backwards and interacting with the moving LF cone.
The HF interaction with moving cone of main driver can be negated with the introduction of a “horn” around the tweeter which prevents HF sound from travelling backwards (or reduces the intensity of soundwaves travelling backwards), without introducing resonant effects.
The LF sound can escape freely through the gap between the horn and bezel.
This coaxial type speaker design exists in various prior art forms, mostly on larger drive units (see
Acoustic performance can be further improved with the addition of “feathering” to the edge of the tweeter horn.
The axes are dB (vertical axis) against Frequency (Hz) (Horizontal axis). The effect of the notches in the rim of the tweeter horn can be seen in the plot of
LED Speaker Integration with Improved Acoustics
The tweeter and LED assembly are mounted in a carrier 912 suspended by the grill 910 above the LF cone 916. The carrier may be made from aluminium or zinc or any other material of high thermal conductivity. The carrier 912 moves heat away from the LEDs into the air through the moulded grille 910.
The LEDs are arranged in a vertical “tombstone” orientation. A reflector is provided to reduce the thickness of the LED ring and to increase the number of LEDs from 8 to 20
The lens of the LED assembly becomes part of the tweeter horn.
The tweeter horn “feathers” into a grille, as can be seen in
The diameter of the voice coil may be increased to clear the LED tweeter carrier and use the integrated cone and dust cap for the LF driver. This addresses the problem of air gap leak and provides a device exhibiting improved acoustic performance.
The light source is suitably recessed. Wires from the tweeter and LED are run under the grille out of sight.
A variant of this preferred specific embodiment is shown in
An Infra red (IR) proximity sensor and lens 954 are integrated into this variant and placed above the tweeter, acting as a “phase plug”. Wires from the LED, tweeter and IR proximity sensor are run under one of the arms of this carrier via a ribbon cable 956. A flexible circuit 958 for a microphone array is also provided. The roll surround 960 may be configured as shown or, more preferably, may be inverted.
In a further variant of this embodiment, a dispersion cone is placed above the tweeter and the IR sensors sit on the top of the cone. The wires of the IR proximity sensor are run through the cone to combine with the LED and Tweeter cables, which then run under the arms of the carrier via a ribbon cable 956.
Features from these variants of the first embodiment may be combined, as will be appreciated by the skilled person.
LEDs in the vertical orientation may emit inwards towards the tweeter. A conical polished polycarbonate white optic reflector redirects light forward and outward through the horn profile lens.
Increasing the number of LEDs to 20 improves the possibility of colour mixing by alternating cool and warm LED packages and independently controlling the brightness.
As opposed to mounting the LEDs in vertical “tombstone” configuration, the LEDs 1210 may be mounted horizontally, as shown in LED assembly of
In a specific example, 8 LEDs can be arranged in a 24 mm diameter ring. The diameter is denoted by “x” in
In an alternative example shown in exploded sectional view in
Advantageously, the combined grille and LED carrier component, simplify construction and assembly and provide an improved surface area for heat transfer from the LEDs. This configuration also removes split lines from cosmetic surfaces.
Advantageously, this configuration provides a more robust heat path for heat removal from the LEDs by thermally connecting them to the thermal mass of the magnet steel. More powerful variants of the lighting and speaker system may benefit from this configuration.
Another version of this would remove the square bezel and allow for the combined lighting and loudspeaker device to be recessed into the ceiling. This creates an option where the lighting speaker units can be installed so that they are flush with the ceiling and can be concealed within plaster on the ceiling.
The battery may be constantly recharged during use. It can give around 10 minutes of life, to ensure a smooth transition if the light switch is accidentally switched. In this event, settings are saved and there are no speaker pops. The user may be alerted to turn the switch back on and use the app or voice to control the lights. The light switch can now be used as an input by using an on/off on/off pattern as a gesture to reset the system, for example.
In an alternative embodiment, a capacitor may be used in place of the rechargeable battery. The capacitor can store energy from the main power supply as provided while the device is attached. In the event that the power is cut to the main power supply, the capacitor will supply its stored electricity into each individual device until such time as it is out of stored electricity.
In the context of this application, the terms “inner” and “inward” refer to components and directions that are closer to the central axis of the device or towards the central axis of the device. Likewise, “outer” and “outward” refer to components and directions that are further away from the central axis of the device.
“Forward” and “rearward” refer to directions that are towards the room or the ceiling cavity when the device is installed in the ceiling, respectively.
“Annular” means shaped as a ring. In the embodiments shown, the annular components are shown as circular rings and described as “donut-shaped”. However, these components do not need to be circular. They could be square or rectangular or a number of other shapes. In all cases, they will have an inward hole that is characteristic of annular arrangements.
The phase “in communication with” means, in the context of this application, placed adjacent to so that air can flow smoothly between the components. As a result, sound waves may also travel between components that are in communication with each other. Within the meaning of “adjacent”, the components may be spaced apart with additional components in between that allow air to flow smoothly between the components (such as spacers, washers, thermal coupling materials and the like).
“Frustoconical” means having the shape of a frustum of a cone. “Frustopyramidal” means having the shape of a frustum of a pyramid. An “inner frustoconical surface” is the inside surface of the frustrum of the cone and an “outer frustoconical surface” is the outside surface.
In the case where the annular LED assembly is not a circular “donut-shaped” annular assembly, frustopyramidal surfaces may be more appropriate for the reflectors and tweeter horns, rather than frustoconical surfaces.
Various embodiments have been described above to illustrate a number of different advantageous features. As will be appreciated by the skilled person, these features may be combined in various ways to produce many different lighting and speaker devices.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1806194.5 | Apr 2018 | GB | national |
| 1815709.9 | Sep 2018 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/GB2019/051082 | 4/16/2019 | WO | 00 |
