OMNI-DIRECTIONAL AIRPORT-TAXIWAY LIGHT

Abstract

The invention relates to an omni-directional airport taxiway light comprising a housing with a lower casing, with an upper casing mounted to the lower casing, and with an outer lens mounted to an opening of the upper casing, wherein the upper casing provides a substantially flat upper surface and wherein a first sealing is mounted between the lower casing and the upper casing and a second sealing is mounted between the upper casing and the outer lens, comprising a light emitting diode positioned in the housing below the outer lens so that light of the light emitting diode is emitted in the direction of the outer lens, comprising a carrier for the light emitting diode positioned in the housing, and comprising an inner lens located in the housing between the light emitting diode and the outer lens, wherein the carrier is a flat carrier which is mounted to the upper casing and wherein the light emitting diode is mounted to the carrier.

Claims

1. An omni-directional airport taxiway light comprising: a housing with a lower casing, with an upper casing configured to be mounted to the lower casing, and with an outer lens being mounted to an opening of the upper casing, wherein the upper casing provides a substantially flat upper surface and wherein a first sealing element is disposed between the lower casing and the upper casing and a second sealing element is disposed between the upper casing and the outer lens to form an inner space of the light that is sealed from a medium surrounding the light; a light emitting diode positioned in the housing below the outer lens and configured to emit light in a direction towards the outer lens; a carrier supporting the light emitting diode, the carrier being positioned in the housing; an inner lens located in the housing between the light emitting diode and the outer lens; wherein the carrier is a flat carrier and is mounted to the upper casing and wherein the light emitting diode is mounted to the flat carrier.

2. The omni-directional airport taxiway light of claim 1, wherein in that at least one of an inner surface of the inner lens and an inner surface of an outer lens provides an optical structure configured to emit a substantial portion of the light of the light emitting diode within an angular range of 0 to 10 with respect to a plane that is defined by the substantially flat upper surface of the upper casing.

3. The omni-directional airport taxiway light of claim 1, wherein the carrier is a disc-shaped carrier.

4. The omni-directional airport taxiway light of claim 1, wherein an annular contact area is provided between the carrier and the upper casing.

5. The omni-directional airport taxiway light of claims 1, wherein the opening of the upper casing provides a recess on a lower side thereof and wherein the carrier with the light emitting diode is positioned within the recess.

6. The omni-directional airport taxiway light of claim 1, wherein the inner lens has a domed shape.

7. The omni-directional airport taxiway light of claim 1, wherein the opening has diameter and this diameter increases towards the carrier.

8. The omni-directional airport taxiway light of claim 7, wherein the opening is surrounded by at least a first shoulder of the upper casing facing towards the lower casing and wherein the first shoulder provides an abutment structure for the outer lens.

9. The omni-directional airport taxiway light of claim 7, wherein at least a section of the opening is surrounded by a tapered boundary or the upper casing, said tapered boundary dimensioned to center a position of the outer lens in the opening.

10. The omni-directional airport taxiway light of claim 7, wherein the opening is surrounded by at least a second shoulder of the upper casing facing towards the lower casing and wherein the second shoulder provides a block against which the carrier is clamped.

11. The omni-directional airport taxiway light of claim 1, wherein the outer lens is positioned in the opening and clamped by the carrier against a block being provided by the upper casing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the following, the invention will be described by way of example, without limitation of the general inventive concept, on examples of embodiment and with reference to the drawings.

[0017] FIG. 1 shows a cross-sectional view of an omni-directional airport taxiway light and

[0018] FIG. 2 shows detail X as indicated in FIG. 1.

[0019] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

[0020] FIG. 1 shows an omni-directional airport taxiway light. The omni-directional airport taxiway light comprises a housing with a lower casing 1, an upper casing 2 mounted to the lower casing 1 and with an outer lens 3 mounted to an opening (i.e. a through hole) of the upper casing 2. The outer lens 3 is thus a transparent cover and can be of any suited material, like e.g. glass. The diameter of the opening increases towards the lower casing (thus in the downward direction), while its shape provides steps and/or recesses. The steps provide down facing shoulders. One of these shoulders provides a block or stop or abutment structure for the outer lens against an upward movement of the outer lens. A second shoulder provides stop for a carrier 6 being bolted from below against the upper casing 1.

[0021] A first sealing element 14 is mounted between the lower casing 1 and the upper casing 2 to tightly, sealing connect those two together. A second sealing element 15 is mounted between the upper casing 2 and the outer lens 3 to tightly fasten those two together. The housing defines a sealed inner space 4 of the omni-directional airport taxiway light.

[0022] The omni-directional airport taxiway light further comprises a light emitting diode 5 as a light source, the carrier 6 for supporting the light source 5 and an inner lens 7. The light emitting diode 5 is directly mounted to the carrier 6 and positioned in the housing below the outer lens 3 so that light of the light emitting diode 5 is emitted in the direction of the outer lens 3. The outer lens is essentially flush with the top surface of the upper casing 2. The inner lens 7 is located between the light emitting diode 5 and the outer lens 3. The optical axes of the light emitting diode, the inner lens 7 and the outer lens 3 are aligned with and as indicated by the dash dotted line.

[0023] An electronics assembly 16, i.e. circuitry 16 for controlling the LED-current, is positioned in the sealed inner space 4. The electronics assembly 16 is mounted to the lower casing land heat losses of the circuitry is thus dissipated essentially by the lower casing and not by the upper casing, thereby further enhancing cooling of the LED. The electronics assembly 16 can provide a sealing, e.g. it may be sealed e.g. by some potting.

[0024] The flat carrier 6 supports the light emitting diode on a flat surface 17 (see FIG. 2) facing the lenses 3, 7. The flat carrier 6 is made of a sheet of metal and can be considered as a metal plate or a metal disc. It can be produced by jet cutting or laser beam cutting for example. E.g. the flat carrier 6 can be made of aluminum and provides good thermal properties such as heat conductivity. A plurality of screws 19 is provided to mount the flat carrier 6 to the upper casing 2. To this end the upper casing provides a downward facing shoulder surrounding the opening as stop for the carrier 6. The carrier is clamped by the screws 19 against the downward facing shoulder. An annular contact area 18 is thus provided between the flat surface 17 of the carrier 6 and the upper casing 2 enabling an enhanced heat transfer between the light emitting diode 5 via the carrier 6 to the upper casing 2. From the upper casing 2 the heat is dissipated.

[0025] A ring-shaped plate 20 is located between the outer lens 3 and the carrier 6. The plate 20 supports the outer lens 3 on the carrier 6 and defines a vertical distance between the light emitting diode 4 and the outer lens 3.

[0026] An additional plate is located as spacer between the plate 20 and the outer lens 3 and the inner lens 7. The additional plate enables to center the inner lens 7 relative the outer lens 3.

[0027] Both the inner lens 7 and the outer lens 3 cover the light emitting di-ode 5. Light emitted by the light emitting diode 5 passes through both lenses 3, 7. The inner lens 7 has a dome shape and provides a concave inner surface 8 (that faces away from the outer lens 3). Light from the diode 5 is outcoupled through the lenses 3 and 7 outwardly through at least a portion of the outermost surface of the lens 3. In one specific embodiment, the inner surface 9 of the outer lens 3 (that faces the inner lens) provides an optical structure which is designed for redirecting a substantial portion (defined as at least 80 percent) of the light of the light emitting diode 5 to an angular range 10 of 0 to 10 with respect to a plane 11 defined by a substantially flat upper surface 12 of the upper casing 2. In this specific case, the light output from the embodiment is perceived, in a cross-section transverse to the axis (shown with a dot-dashed line A in FIG. 1), as a ring or annulus of light or at least an arcuate portion or segment of a ring of light defined by such angular distribution at the peripheral portion of the outermost surface of the lens 3. (The remaining portion of the light output from the diode 5 may be emitted through at least a portion of the flatter, central portion of the outermost surface of the outer lens 3 that is circumscribed by the peripheral portion). In an embodiment in which the light transmission of the outermost surface of the lens 3 is appropriately reduced or blocked, the light output may be formed spatially-asymmetrically in that either of the ring, peripheral portion of the output (emanating within the preferred angular range identified above) and the spatially-central portion of the output (emanating through the flatter central section of the outermost surface of the lens 3) appear spatially incomplete. For example, in related embodiments, the overall light output is dimensioned as a ring or annulus fully surrounding substantially dark(er) central area or as an arcuate band of light bent around a substantially dark(er) area. The upper surface 12 provides the opening for mounting of the lens 3.

[0028] The lower portion 13 of the opening in a lower surface of the upper casing 2 is structured as a recess or step. The flat carrier 6 is positioned within and/or abutted against the portion 13. The light emitting diode 5 is mounted to the flat surface 17 of the carrier 6 and located next to the lenses 3, 7. Heat of the light emitting diode 5 is transferred to the upper casing 2 via the carrier 6 and dissipated from the upper casing 2.

[0029] Above we used the terms upwards and downward to indicate the relative positions of pieces. These terms are to be understood that the surface 12 of the upper casing faces upwards. Its diametrically opposed surface, which provides a block for the lower casing is in turn facing downwards. Thus, the term upwards and downwards refer to the orientation of the light under assumed normal mounting conditions, regardless of its real orientation in space. For example, during the mounting process it may be advantageous to flip the upper casing 2 such that its surface 12 faces towards the earth, but of course it remains the top surface.

[0030] It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide an omni-directional airport taxiway light. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

LIST OF REFERENCE NUMERALS

[0031] 1 lower casing [0032] 2 upper casing [0033] 3 outer lens [0034] 4 sealed inner space [0035] 5 light emitting diode (LED) [0036] 6 carrier [0037] 7 inner lens [0038] 8 inner surface [0039] 9 inner surface [0040] 10 range [0041] 11 plate [0042] 12 upper surface [0043] 13 opening [0044] 14 sealing [0045] 15 sealing [0046] 16 electronics assembly [0047] 17 surface [0048] 18 contact area [0049] 19 screw [0050] 20 plate