FR2557364A1 - COMPACT FLUORESCENT LAMP HAVING A SINGLE SIDE ASSEMBLY - Google Patents

Abstract

THE INVENTION CONCERNS A COMPACT FLUORESCENT LAMP WITH A SINGLE SIDE CAP. THE SAID LAMP 1 IS EQUIPPED WITH A CULOT4 CONTAINING AN ELECTRONIC BALLAST. THE BULB3 IS PROVIDED, IN THE REGION OF THE DIT CULOT4, WITH A THERMOREFLECTING LAYER9 TO PROTECT THE ELECTRONIC COMPONENTS8 FROM ADDITIONAL HEATING. APPLICATION TO COMPACT FLUORESCENT LAMPS.

Description

The present invention relates to a compact fluorescent lamp provided with

  a single-sided pellet with

  electrical components housed in this base.

  It is well known that discharge lamps must have a choke or priming element to light the lamp, as well as a ballast to limit the current of this lamp. Until now, these electrical components have been housed in lamps specially made for lamps of this type. Recently, especially in the case of compact fluorescent lamps, the tendency is to dispose the priming element and the ballast in the base of the lamp or in a separate part

  constituting an intermediate pellet. Another stage of evolution

  This is to use so-called electronic ballasts instead of conventional induction coils or other similar electromagnetic elements. In these

  devices, the 50 Hz mains voltage is generally conver-

  in a high frequency voltage between 30 ldHz and 50 kHz. The current limitation is then also ensured by an induction coil, which can however be very

  small because of the high frequency.

  Nevertheless, the components used in these devices are very sensitive to heat. Even if the heat generated by the ballast itself is very low, this device must be housed in a closed space inside the base or the intermediate base, which aims at avoiding any

  additional heating from the outside, that is to say

evoked by the lamp.

  The object of the invention is to protect the electronic components incorporated in the device from overheating.

casement boot.

  According to the invention, this object is achieved by the fact that the bulb of the lamp is provided, in the region of the base, with a layer reflecting the radiation. This layer is in particular heat reflective, so that the heat transferred by the lamp does not heat the electronic components in addition to the heat released by these components

properly so called.

  Aluminum for example is suitable for. constitute this

  thermoreflective layer and, when applying the coating,

  It is important to ensure that the region around

  power supply remains unobstructed to avoid

short circuits.

  It has proved particularly advantageous to use a layer of electrically non-conductive material, such as

  for example, aluminum oxide or titanium dioxide.

  This layer can be deposited by immersion, spraying

  (with a binder), or by an electrostatic process. The coating

  by the thermoreflective material can be performed

  both on the outside and on the inside of the bulb.

  Another problem, especially in fluorescent lamps, is

  your compact, is lifted by the light scattered towards the

  side of the pellet. To make the lamps, a long discharge tube

  ge is bent in some way so that it describes one or more meanders. In this way, it becomes short enough to present the dimensions of a conventional incandescent lamp. It follows, however, that a considerable part of the scattered light is directed towards the base, on which it is most often wasted by absorption and by multiple reflection. Thanks to the partial reflection of the bulb to

  proximity to the base, this light is referred to

  main distribution of the lamp. This confers the advantage

  to avoid to the largest extent any loss of

surely.

  The invention will now be described in more detail by way of non-limiting example, with reference to the drawing.

  annexed in which the single figure is a fragmen-

  partially cut off a compact fluorescent lamp

  equipped with a ballast arranged in its base.

  The compact fluorescent lamp 1 shown in section consists of two discharge compartments 2a and 2b which are bent, open on one side and housed in a bulb 3,

as well as a pellet 4.

  The base 4 comprises a hollow body 5 surrounding annuli

  the lower part of the bulb 3, as well as an adjoining threaded end 6 allowing the screwing of the lamp 1 in

  a socket for incandescent lamps. Electrical components

  8, arranged on a conductive plate 7 in the hollow body 5 of the base 4, fulfill the functions of a

  priming device and a lamp ballast 1.

  In order to protect these electronic components 8 from excessive heat, the bulb 3 is provided in the region of the base 4 with a heat-reflecting layer 9 of aluminum oxide. Since this layer 9 also reflects the visible light, we take advantage of this advantage for

  keep the light losses as low as possible.

  It goes without saying that many modifications can be made to the lamp described and shown, without leaving

of the scope of the invention.

Claims (4)

  1. A compact fluorescent lamp with a single-sided base and comprising electrical components incorporated in this base, lamp characterized in that its bulb (3) is provided in the region of said base (4), one layer (9) S reflecting radiation.   2. Lamp according to claim 1, characterized in that the layer (9) reflecting the radiation is in particular thermoreflective.   3. Lamp according to claim 2, characterized in that the heat-reflecting layer (9) consists of a   electrically non-conductive material.   4. Lamp according to claim 2, characterized in that the heat-reflecting layer (9) consists of a metallic material.