Coupling component for lighting devices

A coupling component has a groove for receiving a rim of a mouth portion of a lighting body protection bulb. The groove includes sculptured formations to keep the mouth portion rim received in the groove spaced from the bottom of the groove to produce a discontinuous contact between the mouth portion rim and the groove.

RELATED APPLICATIONS

The present application is a national stage entry according to 35 U.S.C. §371 of PCT application No.: PCT/EP2010/063678 filed on Sep. 17, 2010, which claims priority from Italian application no. TO2009A000725 filed on Sep. 23, 2009.

TECHNICAL FIELD

Various embodiments relate to lighting devices of the integrated type including a light source, such as a halogen lamp, and a corresponding power supply circuit such as an electric transformer.

BACKGROUND

FIG. 1shows schematically, by way of example, a lighting device10comprising:a light source12anda corresponding electrical power supply circuit14.

The light source can comprise a lighting body (or “burner”) which may be, for example, a halogen lamp120intended to reach temperatures of about 200° C. during operation. Consequently, while it is normally provided with its own bulb, of teardrop shape for example, the lamp120can be placed inside a bulb122made from transparent material (such as glass) which is intended to ensure that the flow of light is not impeded, while also preventing any undesired accidental contact with the lighting body120at its operating temperature.

The joint or connection to the housing containing the electrical power supply circuit14is made by means of a joining element20generally referred to as “tape”.

To ensure that the heat originating from the light source12(in other words, from the lighting body120) does not degrade the properties of the component20, this component is made from materials which combine the properties of heat-resistance and stability (such as glass, ceramic materials or metals). However, these materials can give rise to problems in respect of weight, cost and low mechanical strength (for example, materials such as glass or ceramics have an intrinsically low resistance to impact), and are also difficult to model or mold. If plastics or resin materials are used, this may give rise to the release of chemical substances which can be deposited on the bulb122, which, on the one hand, reduces the transparency of the bulb, impeding the diffusion of the light flux, and, on the other hand, imparts a stained appearance to the bulb, with negative results in terms of its visual appeal.

SUMMARY

The inventors have discovered that, in order to produce the component in question, it is necessary to provide solutions which can replace materials such as glass, ceramic materials or metal, and which are lighter, more economical and stronger in mechanical terms, while also being easier to model or mold because they are made from a material with excellent thermal insulation properties, such as plastics material, which can be used without giving rise to the other drawbacks described above.

The claims form an integral part of the technical teachings provided herein in relation to the invention.

Various embodiments can provide a very simple solution which has no appreciable effect on the production of the housing of an integrated lighting device.

Various embodiments can provide a compact solution which has no effect on the lighting device and which allows the lighting device to be given an appearance which is identical or at least very similar to that of a conventional bulb lamp.

Various embodiments also provide a good circulation of air between the external environment and the interior of the bulb, thus simultaneously reducing the temperature inside the bulb and allowing the exit of any chemical particles diffused inside the bulb, while also making it possible to provide the minimum safety distances and prevent any contact with the “live” parts of the lighting device by a correct design of the shape of the housing.

DETAILED DESCRIPTION OF EMBODIMENTS

The reference to “an embodiment” in this description is intended to indicate that a particular configuration, structure or characteristic described in relation to the embodiment is included in at least one embodiment. Therefore, phrases such as “in an embodiment”, which may be present in various parts of this description, do not necessarily refer to the same embodiment. Furthermore, specific formations, structures or characteristics may be combined in a suitable way in one or more embodiments.

The references used herein are purely for convenience and therefore do not define the scope of protection or the extent of the embodiments.

FIG. 2shows in greater detail the structure of the light source12described previously with reference toFIG. 1.

As stated previously, the light source12comprises a lighting body proper120(such as a halogen lamp, also called a “burner”) surrounded by a bulb122of approximately spherical or bulb-like shape with an overall tray-like or cup-like structure (which appears inverted in the view shown inFIG. 2). The bulb122also has a mouth rim124(which is circular in the embodiment illustrated herein) designed to be received in a peripheral groove22of the component (generally called a “tape”) indicated by20inFIG. 1which was described above. As can be seen more clearly in the view ofFIG. 3, in the embodiment illustrated herein the component20is of generally disk-like shape with a bottom wall202of overall concave shape designed to define an area for the mounting of the lighting body120in a central position and therefore on the bottom part of the bowl formed by the wall202.

For example, two radial ribs204can extend upward from the bottom wall of the component20to permit the insertion, with a positive connection, of a two-piece plate206in the shape of an inverted tray, which carries the lighting body120in a central position.

The view ofFIG. 3also shows that the groove22intended to receive the mouth rim124of the bulb122lies between two annular walls, namely:an “outer” annular wall208, defining the external profile of the general disk-like configuration of the component20, andan “inner” annular wall210, which delimits peripherally the central part of the bottom wall202of the component20. Between the two annular walls208and210there are radial ribs212forming raised (or more generally “sculptured”) formations in relation to the bottom of the groove22. Because of the presence of these formations212, the coupling of the bulb122to the component20by the insertion of its mouth rim124into the groove22does not create any continuous contact between the mouth rim124and the bottom of the groove22. In other words, the formations212help to keep the mouth rim124of the bulb122slightly “elevated” above the bottom of the groove22, thus ensuring that the contact between the mouth rim124and the body of the component20is actually a discontinuous contact, which is, for example, capable of allowing a certain amount of air to flow between the mouth rim124of the bulb122and the peripheral edge of the component20.

The reference214also indicates a set of openings provided in the bottom wall202of the component20such that a further flow of air is permitted between the external environment and the interior of the bulb122.

As can be seen more clearly in the views ofFIGS. 5 and 6, in various embodiments, the mouth rim124of the bulb122is inserted into the groove22and, because of the presence of the ribs212, this insertion does not create a sealed connection but allows a degree of circulation of air in the internal environment of the bulb, such that the temperature inside the bulb can be reduced, and at the same time any chemical particles which have diffused into the bulb can pass out of it.

Thus a form of labyrinth is created between the parts concerned, this labyrinth allowing a flow of air but also meeting the requirements of electrical insulation in terms of creepage and clearance.

In various embodiments, the component20makes it possible to overcome the problems related to the high temperature of the lighting body120and to the fact that, when inserted into the bulb122, the lighting body120is not directly exposed to the external environment and is therefore not directly ventilated.

As stated above, the component20can support the plate composed of two complementary portions206of semicircular shape, which also provide an electrical connection between the lighting body120and the other parts of the device10, for example by means of edge portions bent to lie behind the inner face of the wall210. In particular, the electrical connection can be made by means of blade contact elements as described in a patent application for an industrial invention filed on the same date by the present applicant.

In various embodiments, the component20is made from a plastics material with properties of high heat-resistance, for example the material known as LCP.

The component20, and particularly the bottom wall202, is also suitable for forming the mechanical connection with the power supply circuit14using a solution in which a separating air gap is formed as described in another patent application for an industrial invention filed on the same date by the present applicant.

The bulb122can be fixed to the component20by gluing or simply by means of a mechanical friction fit.