Aircraft LED light unit

Abstract

An aircraft LED light unit is disclosed that includes a flat electric circuit device having a first main surface, a second main surface and at least one side surface extending between the first main surface and the second main surface, power supply circuitry, disposed in the electric circuit device, at least one heat transport element, disposed in the electric circuit device, and at least one LED. The at least one LED is arranged on the at least one side surface of the electric circuit device, is electrically coupled to the power supply circuitry, and is in heat exchange relationship with the at least one heat transport element.

Claims

1. An Aircraft LED light unit comprising: a flat, substantially cuboid electric circuit device having a first main surface, a second main surface and four side surfaces extending between the first main surface and the second main surface at respective circumferential portions of the first main surface and the second main surface, power supply circuitry, disposed in the electric circuit device, at least one heat transport element, disposed in the electric circuit device, and a plurality of LEDs, wherein the plurality of LEDs are arranged adjacent to each other along a first side surface of the four side surfaces of the electric circuit device, are electrically coupled to the power supply circuitry, and are in heat exchange relationship with the at least one heat transport element wherein the electric circuit device is a packaged electronic component, forming a casing for the power supply circuitry and the at least one heat transport element, and wherein the plurality of LEDs are at least partially integrated into the packaged electronic component.

2. The Aircraft LED light unit according to claim 1, wherein a lateral extension of each of the first main surface and the second main surface, measured in the directions of their respective smallest extensions, is at least 3 times, in particular at least 5 times, the largest distance between the first main surface and the second main surface at the at least one side surface.

3. The Aircraft LED light unit according to claim 1, wherein the electric circuit device integrates the power supply circuitry and the at least one heat transport element in three dimensions.

4. The Aircraft LED light unit according to claim 1, wherein the at least one heat transport element is at least one wire or at least one plate, in particular a silver or copper wire or plate.

5. The Aircraft LED light unit according to claim 1, wherein the at least one heat transport element extends away from the at least one side surface in a substantially perpendicular direction.

6. The Aircraft LED light unit according to claim 1, wherein the at least one LED is glued, soldered or welded to the electric circuit device.

7. The Aircraft LED light unit according to claim 1, further comprising at least one optical element, such as a lens or reflector or shutter, associated with the at least one LED for shaping an output light intensity distribution of the at least one LED.

8. The Aircraft LED light unit according to claim 7, further comprising a mechanical coupling mechanism that consists of a first coupling part, associated with the at least one optical element, and a second coupling part, comprised in the electric circuit device, wherein the first coupling part and the second coupling part are adapted to allow for a snapping on of the at least one optical element with respect to the electric circuit device.

9. The Aircraft LED light unit according to claim 8, further comprising an additional flat electric circuit device, the additional flat electric circuit device being stacked vertically with the electric circuit device and also comprising power supply circuitry, at least one heat transport element and at least one LED.

10. The Aircraft LED light unit according to claim 1, further comprising a flat control circuit device, the flat control circuit device being stacked vertically with the electric circuit device and comprising control circuitry adapted to control the at least one LED of the electric circuit device.

11. The Aircraft LED light unit according to claim 1, further comprising a flat heat transport device, comprising at least one heat transport element, wherein the flat heat transport device has no electric connections and is adapted to be coupled horizontally to the electric circuit device, with the at least one heat transport element of the heat transport device configured to be coupled to the at least one heat transport element of the electric circuit device.

12. The Aircraft LED light unit according to claim 1, wherein the aircraft LED light unit is an interior aircraft light or an exterior aircraft light.

13. The Aircraft, such as an airplane or a helicopter, comprising at least one aircraft LED light unit according to claim 1, disposed on an inside or an outside of the aircraft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention are described in greater detail below with reference to the figures, wherein:

(2) FIG. 1 shows a packaged electric circuit device with 4 LED's, as used in an exemplary embodiment of an aircraft LED light unit in accordance with the invention.

(3) FIG. 2 shows a schematic diagram of an exemplary embodiment of an aircraft LED light unit in accordance with the invention, having multiple electric circuit devices with LED's.

(4) FIG. 3 shows another exemplary embodiment of an aircraft LED light unit in accordance with the invention, with the electric circuit device being coupled to an optical element.

(5) FIG. 4 shows a cross-section through the exemplary embodiment of FIG. 3.

(6) FIG. 5a shows several components of another exemplary embodiment of an aircraft LED light unit in accordance with the invention.

(7) FIG. 5b shows a portion of the components shown in FIG. 5a, with the LED being coupled to an optical element.

DETAILED DESCRIPTION

(8) FIG. 1 shows an electric circuit device with four LED's for use in an aircraft LED light unit in accordance with an exemplary embodiment of the invention. The electric circuit device 4 is a flat, three-dimensional structure. It is a packaged component and is therefore shown as a solid structure in the drawing of FIG. 1. The electric circuit device 4 has a first main surface 40, a second main surface (not shown due to the viewing direction of FIG. 1), and four side surfaces 44, two of which are shown in the viewing direction of FIG. 1.

(9) One of the side surfaces 44, namely the side surface shown most prominently in the viewing direction of FIG. 1, holds four LED's 10. The LED's 10 are partially integrated into the packaged electric circuit device 4, with the light emission portions protruding from the electric circuit device 4. The four LED's 10 are distributed in an equidistant manner across the side surface 44 facing the viewer of FIG. 1. They are placed adjacent to each other with a distance between them that is similar to the cross-sectional extension of the light emission portions.

(10) FIG. 1 further shows two power supply lines 60 and 62. The two power supply lines 60, 62 are two power supply terminals, with the power supply line 60 supplying a positive voltage and the power supply line 62 supplying a negative voltage. It is pointed out that the voltages of the power supply lines 60 and 62 do not need to be positive and negative on an absolute scale. They need to provide a voltage drop from the power supply line 60 to the power supply line 62 for allowing the electric circuit device 4 to function and to provide power to the four LED's 10.

(11) FIG. 2 shows a schematic diagram of an aircraft LED light unit 2 in accordance with an exemplary embodiment of the invention. The aircraft LED light unit 2 is shown without a housing that is commonly provided for protection of the components of the aircraft LED light unit 2. The housing is omitted for a better illustration of the remaining components.

(12) The aircraft LED light unit 2 comprises a mounting plate 12 and a mounting pole 14. Three electric circuit devices 4, each of which is embodied in almost the same way as the electric circuit device 4 of FIG. 1, are mounted on the mounting pole 14. The electric circuit devices 4 are arranged on the mounting pole 14 in such a way that respective main surfaces of the electric circuit devices 4 face each other. This arrangement of the electric circuit devices 4 is also referred to as a stack of electric circuit devices. In particular, it is referred to as a vertical stack of electric circuit devices 4, because placing one of the electric circuit devices 4 by itself on a table and placing the other electric circuit devices 4 with facing main surfaces on top thereof would result in a vertical stacking of these components. The electric circuit devices 4 are mounted to the mounting pole 14 via mounting holes in the centers thereof. The mounting holes extend through the bodies of the electric circuit devices 4 from the first main surface to the second main surface, respectively. The electric circuit devices 4 are mounted to the mounting pole 14 in a spaced apart manner. In the particular embodiment of FIG. 2, the electric circuit devices are spaced apart by about the same distance as their height, i.e. as their extension of the side surfaces.

(13) The power for the electric circuit devices 4 is supplied from the mounting plate 12 via power supply lines 16 and 18. The power supply line 16 connects the lower side of the mounting plate 12, which is at a positive potential, to the upper side of a control circuit device 20, which will be described below. The power supply line 18 has four individual sections. The first section connects the lower side of the control circuit device 20 to the upper surface 40 of the top most electric circuit device 4. The second section connects the lower surface 42 of the top most electric circuit device 4 to the upper surface 40 of the middle electric circuit device 4. The third section connects the lower surface 42 of the middle electric circuit device 4 to the upper surface of the lowest electric circuit device 4. The fourth section connects the lower surface 42 of the lowest electric circuit device 4 to the upper surface of the mounting plate 12, which is at a negative potential. In this way, a voltage drop from the lower surface of the mounting plate 12 through the control circuit device 20 and the three electric circuit devices 4 to the upper surface of the mounting plate 12 is established.

(14) The respective upper and lower surfaces of the electric circuit devices 4 are conductive plates. In this way, the power supply circuitry of all of the electric circuit devices 4 is comprised of respective conductive coatings on the upper side and the lower side. Each of the electric circuit devices 4 has four LED's 10. In this way, the electric circuit devices 4 correspond to the electric circuit device 4 of FIG. 1, which also supports four LED's 10. The LED's of the different electric circuit devices 4 are oriented in different directions. The four LED's 10 of the top most electric circuit device 4 face the viewer of FIG. 2. The four LED's 10 of the electric circuit device 4, disposed in the middle, have their principal light emission direction to the left in the viewing direction of FIG. 2. The LED's 10 of the lowest electric circuit device 4 have their principal light emission direction towards the right in the viewing direction of FIG. 2. In this way, an aircraft LED light unit is provided that has high illumination capacity in three directions. As is apparent, the stacking and orienting of the electric circuit devices 4 allows for a wide variety of light emission distributions.

(15) All of the LED's 10 are coupled to the respective upper surfaces 40 with one of their terminals and to the respective lower surfaces 42 with the other one of their terminals. In this way, a conductive path through the LED's 10 is established that may provide electrical power to the LED's 10 without any further dedicated driving circuitry within the electric circuit devices 4.

(16) As can be seen from FIG. 2, the LED's 10 are mounted to respective side surfaces 44 of the electric circuit devices 4. In this way, the LED's 10 can make use of the whole bodies of the electric circuit devices 4 for the waste heat transport. This in turn allows for the high integration of the LED's 10 in the aircraft LED light unit 2. Each of the LED's 10 is provided with a heat transport element that runs through the body of the respective electric circuit device 4. As the heat transport elements are disposed within the electric circuit devices 4, they are not shown in the outside view of FIG. 2. Their disposition and functioning will be described with respect for FIG. 4 below.

(17) The aircraft LED light unit 2 of FIG. 2 further has the control circuit device 20, which is also mounted to the mounting pole 14. As discussed above, the control circuit device 20 is supplied with electrical power by the power supply lines 16 and 18. The control circuit device 20 comprises control and driver circuitry, receiving illumination commands and providing the LED's 10 with desired voltage and current levels, as a response to the illumination commands. Placing the control and driver circuitry in a dedicated control circuit device 20 allows for keeping the circuitry in the electric circuit devices 4 to a minimum, leaving the bulk of the available volume for waste heat transfer and allowing a particularly high LED intensity.

(18) However, it is also possible to alter this approach. For example, the control circuit device 20 may comprise the control circuitry, while respective driver circuits are comprised in the electric circuit devices 4. It is further possible that the electric circuit devices 4 are controlled individually by the control circuit device 20, resulting in illumination of certain directions only. In this way, the aircraft LED light unit 2 and its control circuit device 20 may allow for various different illumination modes.

(19) It is pointed out that the portion of the electric circuit device 4, covered with the power supply circuitry 6, and the portion of the electric circuit device 4, not covered with the power supply circuitry 6, may be originally separate elements, which are coupled to each other. Such a coupling along the side surfaces is also referred to as horizontal coupling.

(20) FIG. 3 shows a perspective top view of an aircraft LED light unit 2 in accordance with another exemplary embodiment of the invention. FIG. 3 shows an electric circuit device 4, to which a single LED 10 is mounted. For an easier intelligibility, the mounting plate, mounting pole, and light unit housing are omitted from FIG. 3. In the viewing direction of FIG. 3, the first main surface 40 or upper surface 40 of the electric circuit device is shown. Additionally, two of the four side surfaces 44 can be seen. The electric circuit device 4 comprises a mounting hole 48 for being mounted to a mounting pole, such as the mounting pole 14 of FIG. 2.

(21) The power supply circuitry 6 is comprised of two conductive surfaces, one of which is shown in the viewing direction of FIG. 3. This one conductive surface covers about half of the first main surface 40 of the electric circuit device 4.

(22) The aircraft LED light unit 2 further comprises an optical element 50. This optical element 50 is comprised of a housing, a lens, which forms the end of the housing on one side, and a first coupling part 72. The first coupling part 72 and a second coupling part, comprised in the electric circuit device 4, form a coupling mechanism 70. The second coupling part cannot be seen in the viewing direction of FIG. 3, as it is covered by the first coupling part 72 of the optical element 50. As will be described with respect to FIG. 4, the coupling mechanism 70 allows for a snapping on of the optical element 50 onto the electric circuit device 4.

(23) The optical element 50 has a substantially cylindrical housing, which is arranged around the LED 10. The light emitted from the LED 10 travels through this cylindrical housing and hits the lens of the optical element 50, disposed at the end of the cylindrical housing. The lens shapes the output light distribution of the LED 10. In this way, desired light intensity distributions can be achieved with easily implementable snap-on technology.

(24) FIG. 4 shows a cross-section through the aircraft LED light unit 2 of FIG. 3. The cross-sectional plane is a plane perpendicular to the first main surface 40 of the electric circuit device 4, going through the LED 10. It can be seen from FIG. 4 that the electric circuit device 4 has two conductive surfaces, forming the power supply circuitry 6. These two conductive plates cover a portion of the first main surface 40 and of the second main surface 42, respectively. The LED 10 is in electrical contact with both conductive plates for receiving electrical power.

(25) This cross-section through the aircraft LED light unit 2 shows the heat transport element 8, associated with the LED 10. The heat transport element 8 is a copper wire in the exemplary embodiment of FIG. 4. It may be made of other materials, such as silver, as well as of metallic alloys. The copper wire 8 has a first end in close proximity to the LED 10. It is in thermal exchange relationship with the lower end of the LED 10. There, the wire 8 absorbs waste heat, generated by the LED 10 in use, and transports said waste heat through the electric circuit device 4 away from the LED 10. The copper wire 8 has a second end in the first main surface 40 between the conductive plate and the mounting hole 48. The copper wire 8 may have the second end in a variety of other positions in the electric circuit device 4, depending where heat release points are desirable. It is also possible that a heat transfer plate, made of materials such as copper and silver, extends through a large portion of the electric circuit device 4.

(26) As can be seen in FIG. 4, the first coupling part 72 has a ridge running along an inner surface of the first coupling part 72. The second coupling part 74 comprises two groves in the first and second main surfaces 40, 42. The optical element 50 may be pushed over the electric circuit device 4, resulting in a locking of the position of the ridges in the groves, which locks the position of the optical element with respect to the electric circuit device 4.

(27) Numerous modifications may be made with respect to the exemplary embodiments described herein. For example, it is possible that the electric circuit device 4 does not have power supply circuitry on its surfaces. Instead, the power supply circuitry may be disposed within the body of the electric circuit device 4.

(28) Also, the coupling mechanism 70 may have a variety of different forms. For example, the first coupling part 72 may have a hook shape, which can be pushed onto a bar-shaped second coupling part 74. In this way, a coupling via mechanical snapping-on of the optical element 50 can be achieved as well.

(29) FIG. 5a shows a cross-section through an exemplary electric circuit device 4, as used in an aircraft LED light unit in accordance with another exemplary embodiment of the invention. The cross-sectional plane of FIG. 5a is in parallel with the first and second main surfaces of the electric circuit device 4, which first and second main surfaces are therefore not shown in FIG. 5a.

(30) The electric circuit device 4 supports three LED's 10. Each of the LED's 10 is coupled to two power supply contacts 64, also referred to as electrical traces, via respective solder joints 66. The power supply contacts 64 form the power supply circuitry disposed in the electric circuit device 4. The power supply contacts 64 are provided along the electric circuit device 4. The electric circuit device 4 is made mainly of a dielectric material for isolating the power supply contacts 64 with respect to each other.

(31) For each of the LED's 10, a respective heat transport element 8 is provided, which extends through the electric circuit device 4. The heat transport elements 8 are metallic wires. On the one end, the heat transport elements 8 are in heat exchange relationship with the slugs of the LED's via solder joints 80. On the other end, the heat transport elements 8 are coupled to a heat sink structure 82. The heat sink structure 82 absorbs the heat from the heat transport elements 8 and releases the heat into the ambient air or other gas, provided in the aircraft LED light unit. For this purpose, the heat sink structure 82 has a plurality of fins, which increase the surface area available for heat transfer with the ambient gas.

(32) FIG. 5b shows a portion of the electric circuit device 4 and one of the LED's 10 of FIG. 5a, together with its solder joints 66, 80, its power supply contacts 64 and its heat transport element 8. A description of said elements is not repeated for brevity.

(33) FIG. 5b additionally shows an optical element 50. The optical element 50 has a lens 52, which is supported by a supporting structure, which is represented by two bars in the cross-sectional view of FIG. 5b. The optical element 50 can be clipped onto the electric circuit device 4 via a coupling mechanism. This coupling mechanism may have various different forms. In particular, the coupling mechanism may provide an engagement of the optical element 50 with the first and second main surfaces of the electric circuit device 4. Accordingly, the clipping means cannot be seen in the cross-sectional plane of FIG. 5b. The lens 52 of the exemplary embodiment of FIG. 5b is a convex lens, which converges the light emitted from the LED 10. Other lenses are equally possible, depending on the particular application of the aircraft LED light unit.

(34) While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalence may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teaching of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.