WO2007042493A1

WO2007042493A1 - An half-dipped signaling lamp

Info

Publication number: WO2007042493A1
Application number: PCT/EP2006/067180
Authority: WO
Inventors: Giacomo Rigoni
Original assignee: O.C.E.M. S.P.A.
Priority date: 2005-10-11
Filing date: 2006-10-09
Publication date: 2007-04-19
Also published as: ITBO20050606A1

Abstract

A half-dipped signaling lamp (1) with a base support to be embedded in the ground and at least one light source (3) within the base support. A cap (4), removably connected to the base support and protruding from the ground, has at least one windowed seat (5a, 5b), with an optical prism (6a, 6b) supported in the window. The optical prism (6a, 6b) directs outside the light beam emitted by the light source (3). Reflectors (7) direct the light beam emitted by the light source (3) toward the optical prism (6a, 6b), to maximize the percentage of light beam coming out of the windowed seat (5a, 5b).

Description

AN HALF-DIPPED SIGNALING LAMP

FIELD OF THE INVENTION

The present invention relates to outdoors light sources, with particular reference to half-dipped signaling lamps.

BACKGROUND OF THE INVENTION

People skilled in the art know half-dipped signaling lamps formed by a base support, which is embedded in the ground and houses a plurality of light sources.

A cap, connected to the upper part of the base support, protrudes from the ground and has optical prisms placed in one or more separate windows.

The prisms direct outside the light beams emitted by the light sources.

The lower part of the base support has power and control circuits, which supply the light sources and allow to check the operation state and the physical integrity of the latter.

The cap, usually made of metallic material, can stand continuous action of atmospheric agents and of mechanical compression stresses, caused by vehicles possibly passing thereover .

The half-dipped signaling lamps are used generally in light systems of a certain importance, particularly vast, which serve airports or areas in which the operation continuity is essential for safety reasons.

In case of airport illumination, the regulation requirements establish the maximum allowed protrusion from the ground of the half-dipped signaling lamps (e.g. 6mm), as well as the technical and/or geometrical characteristics of the generated light beam.

A reduced protrusion from the ground leads inevitably to work with windows of the housing seats of the optical prisms which have extremely reduced dimensions.

The known half-dipped signaling lamps include light sources formed by groups of photo-emitting diodes, commonly known as LED (Light Emitting Diode) , cooperating with facing optical lens, usually of plastic material, which convey the light beams toward the corresponding optical prisms, directing them to the relative windows.

The use of optical lens, of any shape, receiving the light beams coming from the groups of LED below and conveying them toward the relative optical prisms, causes remarkable problems related to the limited energetic efficiency, considered as the ratio between the electromagnetic energy of the light beam, which comes out of the windowed seats housing the prisms, and the electromagnetic energy of the light beam emitted directly by the groups of LED.

Actually, the optical lens lead to a high energetic dispersion of the light beam, which is not directed optimally toward the extremely reduced windows housing the optical prisms.

SUMMARY OF THE INVENTION

The object of the present invention is to avoid the above drawbacks by proposing a half-dipped signaling lamp, which maximizes the energetic efficiency, intended as the ratio between the electromagnetic energy of the light beam, which comes out of the windowed seats housing the prisms, and the electromagnetic energy of the light beam emitted directly by the light sources. Another object of the present invention is to propose a half-dipped signaling lamp, which is extremely functional and reliable, and which allows to reduce the energy dispersion of the light beam.

Moreover, the proposed half-dipped signaling lamp is to be characterized by relatively limited production costs, which allows an easy variation of the technical and/or geometrical characteristics of the generated light beam.

The above mentioned objects are obtained, in accordance with the contents of the claims, by a half-dipped signaling lamp, including : a base support to be embedded in the ground and housing at least one light source; a cap, connected removably to the base support and protruding from the ground; at least one windowed seat made in the cap and supporting an optical prism for directing outside a light beam emitted by the light source; the signaling lamp being characterized by reflecting means for reflecting the light beam emitted by the light source toward the optical prism, to maximize the percentage of light beam coming out of the windowed seat.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristic features of the invention are pointed out in the following description of some preferred but not exclusive embodiments, with reference to the enclosed figures, in which:

Figures 1 and 2 show respective top and bottom views of a covering cap of a signaling lamp proposed by the invention; Figure 3 is an enlarged, top view of a particularly significant element of the proposed half-dipped signaling lamp;

Figure 4 is an enlarged, partial bottom view of the covering cap, in a partially assembled configuration;

Figures 5A, 5B are section views taken along A-A of Figure 4, of as many variants of a first embodiment of the proposed signaling lamp;

Figure 5C is a section view taken along A-A of Figure 4 of a second embodiment of the signaling lamp proposed by the invention.

BEST MODES OF CARRYING OUT THE INVENTION

Having regards to the enclosed Figures, the general reference numeral 1 indicates the proposed half-dipped signaling lamp, which includes, in known way, a base support (not shown for sake of convenience) , which is aimed at being embedded in the ground and which has, removably fastened thereto, a cap 4, e.g. a metallic cap, protruding from the ground and having a pair of windowed seats 5a, 5b, e.g. facing each other.

An optical prism 6a, 6b is associated to each windowed seat 5a, 5b for directing outside the light beams emitted by relative photo-emitting diodes (LED) 3, e.g. three, housed inside the base support.

In an innovative way, the proposed half-dipped signaling lamp 1 includes reflecting means 7, aimed at directing the light beams emitted by the groups of LED 3 to the corresponding optical prism 6a, 6b, to maximize the percentage of the light beams coming out of the relative windowed seat 5a, 5b. Advantageously, the reflecting means 7, situated along the path of the light beam from the LED 3 to the relative optical prism 6a, 6b, are removably fastened to the cap 4.

Likewise, each optical prism 6a, 6b is rigidly fastened to the cap 4.

With particular reference to Figure 5A, according to a first embodiment, the reflecting means 7 include parabolic surfaces 7a, having corresponding LED 3 placed at their foci, to obtain a substantially parallel light beam coming out of the windowed seat 5a, 5b.

Actually, in this case, the multidirectional light beam emitted by each LED 3 reflects on the opposite parabolic surface 7a, crossing the base surface of the adjacent optical prism 6a, 6b.

In known way, the light beam inside the optical prism 6a, 6b is reflected on a first inner surface 15 and is refracted through a second outlet surface 16, at the relative windowed seat 5a, 5b, diffusing outside, with a bundle of substantially parallel rays.

Advantageously, the axis of the complete parabola to which each parabolic surface 7a belongs, is substantially orthogonal to the axis of the corresponding LED 3, so as to limit the dispersion of the light beam.

With particular reference to Figure 5B, concerning a variant of the first embodiment, the light beam emitted by each LED 3 is reflected on the opposite parabolic surface 7a, crossing the base of the adjacent optical prism 6a, 6b, without any reflection, and is only refracted through the second surface 16, situated at the relative windowed seat 5a, 5b, diffusing outside, in a bundle of substantially parallel rays. With particular reference to Figure 5C, according to a second embodiment, the reflecting means 7 include elliptic surfaces 7b, having the corresponding LED 3 placed on a primary focus thereof, to obtain a light beam coming out of the seat with the window 5a, 5b, in a bundle of substantially diverging rays.

Actually, in this case, the multidirectional light beam emitted by each LED 3 reflects on the opposite elliptic surface 7b, tending to converge toward the secondary focus, suitably placed out of the optical prism 6a, 6b.

In known way, the convergent light beam is reflected on a first inner surface 15a, suitably going to converge on a second outlet surface 16a, situated at the relative seat with window 5a, 5b, through which the light flow is refracted and diffused outside, in a bundle of substantially divergent rays.

According to a possible variant of the second embodiment (not shown) , the light beam emitted by each LED 3 crosses the 6a without any reflection, and is only refracted through the second surface 16a.

In both cases, the axis of the complete ellipse to which each elliptic surface 7b belongs, is substantially orthogonal to the axis of the corresponding LED 3, so as to limit the dispersion of the light beam.

Generally, the parabolic configuration 7a of the reflecting means 7 is used when the divergence of the light beam is to be minimized, whereas the elliptic configuration 7b is preferred for maximizing the percentage of the light beam coming out of the seats with windows 5a, 5b.

The reflecting means 7 can be in one body (Figure 3) and have a plurality of cavities, parabolic 7a, or elliptic 7b, with or without partition walls. Otherwise, the reflecting means 7 can include separate elements, having parabolic cavities 7a or elliptic cavities 7b.

According to the type of the signal, the optical prism 6a, 6b allows to diffuse horizontally and/or divert laterally the light beam emitted by the LED 3.

In this case, the surfaces 15, 15a, 16, 16a of the optical prism 6a, 6b are subjected to prefixed known processing to give the light beam a distribution with a prefixed intensity .

According to what has been said above, it is easily understood how the proposed half-dipped signaling lamp can maximize the energetic efficiency, intended as the ratio between the electromagnetic energy of the light beam coming out of the seats with the windows, and the electromagnetic energy of the light beam emitted directly by the light sources, advantageously including LED.

The use of reflecting means including parabolic or elliptic surfaces, on whose foci the light sources are placed, allows to maximize the percentage of the light beam coming out of the windowed seats having extremely reduced dimensions, limiting considerably the energetic dispersion.

For this purpose the parabolic or elliptic surfaces are advantageously placed with their axes orthogonal to the axes of the corresponding LED.

In this way, it is possible, with high energetic efficiency, to concentrate the light beams onto the windowed seats even with the caps protruding up to 6mm from the ground, as in case of airport lighting systems.

It is understood that the proposed invention has been described, with reference to the enclosed figures, as a mere, not limiting example. Therefore, it is obvious that any changes or variants applied thereto remain within the protective scope defined by the following claims.

Claims

1. A half-dipped signaling lamp, including: a base support to be embedded in the ground and housing at least one light source (3); a cap (4), connected removably to the base support and protruding from the ground; at least one windowed seat (5a, 5b) made in the cap and supporting an optical prism (6a, 6b) for directing outside a light beam emitted by the light source (3); the signaling lamp being characterized by reflecting means (7) for reflecting the light beam emitted by the light source (3) toward the optical prism (6a, 6b), to maximize the percentage of light beam coming out of the windowed seat (5a, 5b) .

2. A signaling lamp, according to claim 1, wherein said reflecting means (7) are substantially orthogonal to the light source (3) .

3. A signaling lamp, according to claim 1 or 2, wherein said reflecting means (7) include a parabolic surface (7a) and a light source (3) is placed at one focus of a parabola of the parabolic surface, to obtain a light beam going out from the windowed seat (5a, 5b) formed by substantially parallel rays .

4. A signaling lamp, according to claim 1 or 2, wherein said reflecting means (7) include an elliptic surface (7b) and a light source (3) is placed at one focus, to obtain a light beam going out from the windowed seat (5a, 5b) formed by substantially divergent rays.

5. A signaling lamp, according to claim 3 or 4, wherein the light beam emitted by the light source (3) is refracted at least once in the passage through the optical prism (6a, 6b) while exiting the optical prism.

6. A signaling lamp, according to claim 5, wherein the light beam emitted by the light source (3) is reflected during the passage through the optical prism (6a, 6b) .

7. A signaling lamp, according to any of the claims from 1 to 6, wherein said reflecting means (7) are connected to the cap (4) .

8. A signaling lamp, according to any of the claims from 1 to 7, wherein said optical prism (6a, 6b) is rigidly fastened to the cap (4) .

9. A signaling lamp, according to any of the claims from 1 to 8, wherein said light source (3) includes at least one photo-emitting diode.