EP3084920A2

EP3084920A2 - Light bulbs adapter device

Info

Publication number: EP3084920A2
Application number: EP14838818.4A
Authority: EP
Inventors: Gian Pietro Beghelli
Original assignee: Beghelli SpA
Current assignee: Beghelli SpA
Priority date: 2013-12-20
Filing date: 2014-12-16
Publication date: 2016-10-26
Also published as: ITVI20130307A1; WO2015092823A2; WO2015092823A3

Abstract

A light bulbs (LT) adapter device (PA), comprising a threaded seat (CN2) for inserting and electrically connecting the light bulb (LT), further comprising an emergency electronic ballast (A2), which is connected to the supply terminals (T1) of said light bulb (LT), as well as to one or more emergency lighting sources (S2), to least one battery (B1) and to a first electrical connector (T2) of a first electrical connection (CN1); said emergency electronic ballast (A2) being series-connected with a ballast of said light bulb (LT) and being able to control both the battery (B1) charging, by using the electric current flowing through said light bulb (LT), and said emergency lighting sources (S2).

Description

LIGHT BULBS ADAPTER DEVICE

The present invention generically relates to a light bulbs adapter device for incandescent, fluorescent electronic compact or LED bulbs.

More particularly, the invention relates to an adapter device for electronic bulbs, which integrates the function of emergency lighting, suitable to be interposed between any bulb and the original bulb holder.

Lighting lamps are devices providing a converter to convert electric power into light, an electronic circuit to supply said light source, and electro-mechanical system and a transparent protection housing.

Lamps have different shapes on the basis of standardization obtained with technical evolution to build-in possible different light sources; most widespread shapes are the bulb one, with a E27 or E14 screw coupling, created to encapsulate the incandescent filament tungsten, and light tubes with a diameter of 26 mm or 15 mm, born for fluorescent lamps with low pressure indirect emission gas discharge.

The advent of solid state light sources (LED) has evolved technology of the bulb and tube shape, replacing in both cases the content of such bulbs, but preserving their external appearance; thus, LED bulbs was born, which are characterized by a high energy efficiency, in which the LEDs are driven by a built-in electronic power supply converting the 230 V power in a form suitable for LEDs.

White LED bulbs have spread on the market in order to replace almost any traditional filament source, from traditional bulbs with a tungsten filament to the most modern halogen bulbs.

LED bulbs, thanks to the greater energy efficiency, are also replacing electronic bulbs, so-called "compact fluorescent", as well as the availability of small batteries allows the integration of the function of emergency power within the new LED bulbs.

The object of the present invention is that of providing an adapter device for light bulbs, which, interposed between a normal light bulb and its original holder, allowing transforming it into bulb for emergency lighting.

Another object of the present invention is that of providing a light bulbs adapter device, which allows to automatically detecting on the electric system on which it is installed a condition of activation of the emergency lighting, regardless of the state of the switch of the system. Another object of the present invention is to provide a light bulb adapter device, which allows using the traditional bulbs without changing existing lamp holders and/or lighting installations.

Further object of the invention is to provide a light bulbs adapter device, which is able to carry out the monitoring of the emergency condition with very low energy consumption.

These and other objects are achieved by a light bulbs adapter according to the enclosed claim 1 ; other technical detailed features according to the invention are provided in the further dependent claims.

Advantageously, the present invention relates to a new adapter for incandescent, fluorescent electronic compact (CFL) or LED bulbs, which integrates the function of emergency lighting and that can be interposed between any bulb and the original holder, with the following functions:

- in presence of a 230V (AC) power, the bulb mounted on the adapter device switches on with a full light and simultaneously recharges the emergency battery built-in the adapter device;

- if the disconnecting switch of one of the two wires feeding the bulb holder or tube is turned off, the bulb mounted on the adapter is switched off, ceasing charging the battery built-in the adapter device and the bulb goes in a waiting state (stand-by);

- if there is no voltage on the whole circuit of the bulb holder or upstream the system, the bulb remains switched off, but a reduced light built-in the adapter device in an emergency state is switched on.

Further objects and advantages of the present invention will be evident from the following description, which refers to an exemplificative and preferred, but not limiting, embodiment of the light bulbs adapter device according to the invention, and from the enclosed drawings, wherein:

- figure 1 shows a switching on system of a LT bulb coupled with the adapter device PA according to the present invention, with interruption of the phase L by switch I;

- figure 2 shows a switching on system of a LT bulb coupled with the adapter device PA according to the present invention with interruption of the phase L, by switch I, and with emphasises of the parasitic capacitances CPC to other conductors C of the electrical system subjected to phase L potential; - figure 3 shows a switching on system of a LT bulb coupled with the adapter device PA according to the present invention bulb with interruption of neutral N and with switch I;

- figure 4 shows a switching on system of a LT bulb coupled with the adapter device PA according to the present invention with interruption of neutral N, by switch I, and with emphasises of the parasitic capacitances CPN towards ground;

- figure 5 shows a schematic block diagram of a LT bulb to be coupled with the adapter device PA according to the present invention, realised for a threading coupling system;

- figure 6 shows the electric scheme of the light bulbs adapter according to the present invention;

- figures 7A, 7B and 8 show a series of perspective views of a first embodiment of the light bulbs adapter according to the present invention;

- figures 9A, 9B and 10 show a series of perspective views of a second embodiment of the light bulbs adapter according to the present invention;

- figures 11A, 11B and 11C and 12 show a series of perspective views of a third embodiment of the light bulbs adapter according to the present invention.

With particular reference to enclosed figures 5 and 6, bulb LT, that can be an incandescent, fluorescent electronic compact or LED bulb, can be inserted within a threaded seat CN2 of the adapter device PA according to the present invention, comprising an emergency ballast A2, connected to the electric coupling T1 of bulb LT, to a series of light sources S2, to a group of batteries B1 and to an electrical connector T2.

Emergency ballast A2, built-in the adapter device of bulb holder PA is comprised of elements D1 , D2, D3, LV1 , B1 , C1, CLDE, R1 , R2, R3, R4, R5, Q1 , Q2, LDE1 , LDE2, LDEN, is connected in series to the supply circuit of the outer bulb LT and manages the charge of the battery B1 , using the electric power passing through bulb LT, as well as emergency light sources S2, mainly comprised of the LED assembly LDE1, LDE2 LDEN only aimed at the sole emergency lighting function.

Ballast A2 also incorporates a controller device CLDE for managing the emergency function, which analyzes voltage across the power supply terminals of the bulb by identifying the emergency condition and distinguishing it from a condition of the ignition switch I off.

The adapter device or lamp holder PA is able to detect, on the system in which it is installed, a condition of activation of emergency lighting (lack of AC power supply of the system), distinguishing it from the simple opening of the ignition switch I of the bulb LT, opening caused by the normal switching off of bulb LT voluntarily controlled by the user.

In this regard, with particular reference to the enclosed figures 1 , 2, 3 and 4, when the switch I is turned on, AC voltage of 230V mains is present at the ends of the two supply ends of the bulb holder PA, on the male connector CN1.

In this condition, bulb LT, connected on the female output connector CN2, is normally turned on and battery B1 built-in the Bulb holders PA is recharged.

When switch I of the circuit opens, bulb LT is turned off as a normal bulb, but emergency circuit continues to monitor the line to detect the presence of power at 230V, 50Hz (or 115V, 60Hz) upstream the switch I.

All cases described in the enclosed figures 1 - 4 can occur: - switch I disconnects the phase conductor L in a system in which the two conductors are well isolated from other electrical lines, that is the typical case of a table or floor lamp with the plug inserted so that the switch properly disconnects the conductor L; in this case (enclosed fig. 1), with switch I open, residual voltage AC remains at the ends of CN1 coupled through the parasitic capacitance of few pF of the same switch. Residual AC voltage is very small but can be measured and it is in the order of few tens of volts;

- switch I disconnects phase conductor L in a system in which the two conductors are adjacent to other power lines of the building, that is the typical case of a ceiling or wall lamp directly wired into a civil electrical system, in which conductor L is disconnected from the switch I, but the part of conductor disconnected runs within ducts and electrical conduits close to other conductors connected to L at potential of 230V, 50Hz (or 115V, 60Hz); in this case (enclosed figure 2), with switch I open, measurable voltage at the ends of CN1 is the sum of the AC voltage coupled through the parasitic capacitance of a few pF of the same switch I and the induced voltage by coupling parasitic capacity CPC with the electrical cables adjacent to the disconnected portion, the latter contribution being of higher entity. AC voltage at the ends of CN1 , without any load, has values within the range from a few volts to a few tens of volts, as a function of the parasites couplings;

- switch I disconnects neutral conductor N; in this case (see enclosed fig. 3 and 4), the conductor L at a higher potential of 230V, 50Hz (or 115V, 60Hz), is always connected to one of two inputs of the bulb holder PA and parasitic capacitances to ground CPN allow easily to couple a voltage of several Volts, without any load, to the ends of CN1 , with switch I open.

In all the above cases, bulb holder PA, using the emergency monitoring and management circuit CLDE built-in ballast A2 of the same bulb holder PA, which is fed by battery B1 consuming only a fraction of the stored energy, is able to measure the AC voltage remaining at its inlet in order to verify its presence and in this case maintains inhibited the ignition circuits of the emergency lighting sources S2 (emergency LEDs).

Then, until voltage at 230V, 50Hz (or 115V, 60Hz) is present upstream the switch I, the bulb holder PA is able to detect its presence and to maintain emergency sources S2 off.

As soon as voltage at 230V, 50Hz (or 115V, 60Hz) is missing upstream the switch I, also residual AC at the inlet of bulb holders PA disappears and emergency control and management circuit CLDE, detecting its absence, automatically turns on emergency LEDs LDE1 , LDE2 LDEN using the energy stored within battery B1 built and possibly adjusts intensity necessary to optimize the exploitation of battery B1.

This regime of operation continues until the emergency management circuits does not detect again the presence of power at 230V, 50Hz (or 115V, 60Hz) upstream of the switch I, in which case the emergency is again inhibited by turning off the emergency ballast A2.

Bulb holder PA is so realised that the monitoring circuits of AC power condition upstream I consume a very small part of power present in battery B1 , thus guaranteeing continuity of operation in a monitoring mode with the switch I open for several months without interruption, e.g. consuming half of the power available in 3 months. In this way it is guaranteed the regularity of operation of a light bulb that is turned on at least once every few days (the ignition of the bulb LT is the only moment during which internal battery B1 is recharged).

Autonomy of operation of the bulb holder PA under emergency conditions can be set between a minimum of 30 minutes and few hours by suitably adjusting the light intensity of emergency sources S2, that is, by varying the intensity of the piloting current.

Optionally, intensity adjustment may be operated so that initially the brightness is more intense to permit to the user to perceive less the reduction of brightness with respect to the ordinary operation.

Subsequently, brightness can be automatically gradually reduced an automatic way so as to maximize duration of battery B1.

Emergency circuits are realised, according to the state of the art of emergency lighting, so as to turn off the emergency light sources S2 when voltage of battery B1 falls below a minimum value order not to damage the same battery B1 (minimum interruption function).

Bulb LT, that can be connected to female connector CN2 at the output of the bulb holder PA can be of any type, within the set power limit the bulb of the lamp holder PA, e.g. equal to 100W.

This bulb LT can then be an incandescent, electronic CFL or

LED electronic bulb.

The operating currents may therefore vary by at least one factor of 10, passing from 450 mArms of a 100W incandescent bulb LT to 30 ÷ 40 mArms of a 4W bulb electronic LT.

In all cases, current absorbed by LT is an alternating current at mains frequency (50Hz or 60Hz), the intensity of which is proportional to the power absorbed by bulb LT.

Further, as shown in the following, bulb holder PA is so realised not to introduce significant voltage drop and to ensure proper charging of battery B1 under all possible operating regimes and with all possible types of bulbs LT connected.

Emergency ballast A2 is connected in series to the supply circuit of bulb LT, between the central end of the male connection CN1 and central end of female connection CN2. Outer ends or connectors T1 , T2 of male and female connections CN1 and CN2 are connected together.

Emergency ballast A2 is then run by supply current of bulb LT, current circulating, for the positive half-wave, within diode D2 and the circuit connected to it (R3, Q2, R5), and, for the negative half-wave, through the diode D1.

Battery B1 , of the rechargeable type, has a nominal voltage between 3.2V and 4V and can be comprised of a series of three 1.2V nominal elements (of the NiCd or NiMH type), or by a single ion lithium element (in one of several possible chemistries, e.g. with nominal voltages of 3.2V, 3.6V or 3.7V), or by other technological solutions with voltages between 3.2V and 4V.

Current limiter Q2, R4, R5 adjusts charging current of battery B1 to vary the conditions imposed on the type of bulb LT connected, while voltage limiter LV1 B1 protects the battery from over-charging conditions.

Power or "transil" Zener diode D3 absorbs excessive current pulses that may occur in the ignition transient of bulb LT, especially if the high power incandescent type, or of the electronic type with input capacitors of large value, protecting the battery B1 and charge management circuits.

Emergency ballast A2 is driven by the programmable controller CLDE, comprised of a microcontroller M1 with integrated amplifier and analog converter.

Controller CLDE is powered directly by battery B1 to which is connected in parallel, measures AC voltage present on the socket of bulb LT by capacitor C1 and consequently pilots emergency LEDs LDE1 , LDE2, LDEN, controlling bipolar transistor Q1.

Operation of the adapter device for bulbs according to the present invention, is substantially the following.

In the presence of power supply at 230Vac, 50Hz (or 110Vac, 60Hz) at the two ends of the connector or socket CN1 , the inlet alternating current passes through D1 and D2, and circulates within outer bulb LT, which is regularly turned on, and current that, for half wave, circulates through D2, charges battery B1.

Voltage across battery B1 raises during the charging operation up to a maximum allowable value determined by shunt voltage regulator LV1 , which intervenes shunting the charging current when voltage reaches the set maximum value, e.g. 4, 2V (for lithium-ion batteries), in order to protect the battery B1 from damage due to overcharging.

Voltage drop introduced by battery B1 for this function is negligible for bulb LT connected to the output, since across the battery B1 are ends at most 4.2V are present, which, added to the voltage drop of diode D2 and the voltage drop on base of Q2 (equal to 0.6V + 0.6V), arrives at 5,4V (voltage drop across the resistor R3 is negligible).

Even in the most unfortunate case of mains voltage equal to 11 OVac, with Vpeak = 155V, voltage drop accounts for about 3% to 4% on the reduction of the input voltage of bulb LT ballast A2.

In case of voltage 230Vac, with Vpeak = 325V, reduction of voltage at input of ballast A2 caused by charging of battery B1 is even more negligible, of the order of 1.5% ÷ 2%.

It is obvious the advantage of this solution with series connection of emergency ballast A2, allowing having a universal product, not requiring adjustments of operating voltage (230V or 110V).

Controller CLDE, correctly powered by battery B1 , measures alternating voltage at the ends of D1 , by capacitor C1 and its own A/D converter, and, verifying the presence of an alternating voltage at the mains frequency with peak to peak amplitude greater than battery voltage, detects presence of mains supply and keeps emergency LEDs LDE1 , LDE2, LDEN turned off, commanding the transistor Q1 turned off.

Shunt regulator LV1 is of the type characterized by a negligible current consumption at the nominal working voltage of battery B1.

Said regulator LV1 , shunting battery B1 regardless of its state at the overcoming of the maximum allowable voltage, advantageously allows operation of bulb LT in an ordinary manner, even if battery B1 aging is no longer able to absorb the charging current.

Obviously, in case of short circuit of battery B1 , the emergency part ceases to function, but the normal operation of bulb LT is guaranteed.

Therefore, bulb LT maintains the function of normal lighting bulb even in case of complete failure of battery B1.

In conditions of presence of the mains supply with switch I of supply circuit of bulb holder PA switched off, bulb LT does not receive the power necessary for its operation, current within bulb LT is virtually zero and battery B1 is not recharged.

Emergency monitoring and management controller CLDE is powered by battery B1 and its power consumption is very low, being it as an average limited to few tens of μΑ. In fact, microcontroller M1 limits its activities to the switching on periods interspersed with "sleep" periods, with a periodicity of some tens of mS.

During activity periods, microcontroller M1 measures the voltage at the ends D1 of capacitor C1 using its A/D converter.

In addition, microcontroller M1 processes alternating voltage measured across D1 with a digital filter, and compares the measured value with an internal set or pre-calculated threshold, to decide whether or not to turn on the emergency LEDs LDE1 , LDE2 LDEN by piloting transistor Q1.

If AC signal value at the mains frequency (50 or 60 Hz) at the ends of D1 is greater than the set threshold, microcontroller M1 maintains transistor Q1 , and consequently emergency LEDs LDE1, LDE2 LDEN, turned off.

Conversely, if measured alternating voltage is lower than the internal threshold, microcontroller M1 turns on transistor Q1 , and consequently the emergency LEDs LDE1 , LDE2, LDEN.

When switch I is turned off, AC voltage at D1 ends coincides with residual AC voltage at the ends of the socket CN1 of lamp holder PA.

In the absence of voltage on the base of the lamp holder CN1

PA, the diodes D1 and D2 are interdicted and show high impedance.

In this condition, microcontroller M1 can measure, thanks to its input high impedance amplifier and by C1 , residual voltage at the ends of socket CN1.

Inlet of bulb LT behaves in the measurement series circuit as a low impedance bipole at the mains frequency, not by introducing attenuations in the alternating voltage to be measured present on the socket CN1 and read at the ends of D1.

In fact, if it is an incandescent bulb LT, switched off bulb has a low resistance value (tens or hundreds of ohms), while if it is an electronic bulb LT, input circuit has always a capacitor of at least a few tens of nF in parallel to the input, which is part of the noise filter.

It is thus realised, in a simple and advantageous way, a circuit architecture that allows in a universal and efficient way measurement with high impedance of the residual voltage at the ends of the socket of the socket CN1 of the bulb holder PA, with bulb LT turned off. if it had used a measuring circuit connected in parallel to the bulb LT, the measurement of the residual voltage to switch I open would not have been possible due to the low impedance of the bulb LT itself.

Determination of the internal threshold of microcontroller M1 can occur in two distinct ways:

1. threshold is set at the factory and cannot be changed during operation to a value determined following experimental setups;

2. threshold is automatically determined by the power supply emergency ballast A2 in a self-adaptive way during operation; in this case the bulb holder PA leaves the factory with a predetermined value and automatically adapts to the operating conditions of the system. This operation mode can be useful in managing cases of systems in which the levels of the AC signal measured have a very wide dynamic range (e.g., in the enclosed figure 1 AC input voltage is very low, unlike the case of enclosed figures 2 - 4, for which AC voltage can be much higher).

Bulb holders PA with an adaptive threshold works in such a way that, delivered from the factory with a predetermined threshold value, at the first turning off of switch I, microcontroller M1 measures the AC signal on D1 and, based on this measure, defines the following actions:

· if voltage is lower than the threshold value, it is an emergency condition, and thus bulb LT is switched on in an emergency mode;

• if voltage is between the threshold value and a maximum value, new threshold is redefined equal to 2/3 of the measured value.

In this way it is possible improving the immunity of operation by ensuring that, even in presence of a spurious residual voltage AC and even in absence of the 230V system power caused by any interference of adjacent systems, emergency function is correctly activated.

LEDs dedicated to emergency lighting LDE1 , LDE2 LDEN are advantageously driven by bipolar transistor Q1 , thus minimizing cost and effectiveness of the driving circuit.

In fact, correct matching of battery voltage (3.2V ÷ 3.7V, depending on the technology chosen for battery B1) and of LEDs used and the small powers for the emergency application, allow the use of a practically direct connection with battery B1 , so that small resistance R2 limits, together with the internal resistance of battery B1 , maximum current with battery fully charged. Discharge of battery B1 , progressively reducing voltage, naturally reduces current in the time in emergency LEDs, with the perfect application of a slow reduction of brightness which, while not being perceived by observer eye, allows to extend at most autonomy of the emergency function, optimizing the exploitation of battery.

Apparent simplicity of the circuit does not sacrifice the electrical efficiency, which is still very high, since nominal voltage of battery B1 is close to the operating voltage of emergency LEDs.

Further, any switching converter would have a lower efficiency due to the small power involved.

Microcontroller M1 is always able to vary the piloting duty cycle of Q1 in order to further modulate intensity of the average current absorbed by battery B1 , in order to optimally exploit available energy.

Modulation frequency PWM is in this case of the order of between 20 to 30 KHz.

Bulb holder PA also has a function of inhibition of the emergency mode (function called "rest mode"), according to which microcontroller M1 analyzes, by means of AC voltage measured on D1 , a sequence of consecutive ignitions of bulb LT (corresponding the sequence of turning on and off of switch I).

In fact, if the user turns on and off bulb LT consecutively for 4 times regularly interspersed by pauses and ignitions of the duration of about 3 seconds each, microcontroller M1 interprets this sequence as a command for inhibition of emergency lighting.

From the last of the four turning off, bulb holder PA is thus placed in an inhibition state and, at this point, bulb holder PA can be uninstalled without that it is turned on in an emergency mode, while preserving battery B1.

Furthermore, microcontroller M1 is in a very low power consumption condition, preserving to the maximum charge of battery B1.

The next turning on of switch I (i.e., when it is again connected to mains voltage), inhibition function is immediately removed and bulb holder PA restores its normal operation with the emergency lighting function activated.

Inhibition function is convenient for transportation of the bulb holder PA by the user and also to preserve the charge of battery B1 after the manufacturing in factory of the same bulb holder PA, prior to the sale and delivery to customers.

Figures 7A, 7B and 8 illustrate a first possible embodiment of industrial realization of the adapter device or bulb holder PA for bulbs LT, according to the present invention.

According to this solution, emergency batteries B1 and the emergency ballast A2 are housed within a circular ring or "buoy" AS coaxial with the female socket CN2.

The light sources S2 and, particularly, emergency LEDs LDE1 , LDE2, LDEN are mounted on the same circuit of emergency ballast A2, arranged on the upper periphery of the circular ring AS and facing behind a cover made up of transparent plastic for the correct lighting of the environment in case of emergency.

Enclosed figures 9A, 9B and 10 illustrate a second possible industrial embodiment of the emergency adapter device or bulb holder PA, according to the present invention.

In this solution, batteries B1 and emergency ballast A2 are housed inside ferrule of connector or male socket CN1 , with an advantageous integration, both as regards the overall volume of the product and for the operating temperatures of batteries B1 , which are lower than in the first solution.

Light sources S2 and, particularly, emergency LEDs LDE1 ,

LDE2 LDEN are arranged on the upper periphery of the entrance of the female part of the connector or socket CN2, behind a transparent plastic protective ring AS1.

Enclosed figures 11 A, 1 B, 11C and 12 illustrate a third possible industrial embodiment of the emergency adapter device or bulb holder PA, according to the present invention.

It is, in this case, a bulb holder PA for fixed installation within a lighting fixture and, in this solution, bulb holder PA, as all the traditional bulb holders, is fixed by means of a threaded metallic tube screwed inside the rear threaded hole F realised at the base of same bulb holder PA and batteries B1 and the emergency ballast A2 are housed within the base of the bulb holder PA, while light sources S2 and, particularly, emergency LEDs LDE1 , LDE2 , LDEN are arranged, as in the second embodiment described in the above, on the upper periphery of the circular ring or "buoy" AS2, facing behind a cover made up of transparent plastic for the correct lighting of the environment in case of emergency.

From the above description they are evident the features of the adapter devices for light bulbs, which is the object of the present invention, as well as the deriving advantages.

Finally it is clear that numerous other variants can be made to the adapter device described without departing from the novelty principles of the inventive idea, as it is clear that in the practical implementation of the invention, materials, shapes and dimensions of the details illustrated may be any according to specific needing and that they can be replaced with other technically equivalent.

Claims

1. A light bulbs (LT) adapter device (PA), comprising a threaded seat (CN2) for inserting and electrically connecting the light bulb (LT), characterized in that said adapter device (PA) includes an emergency electronic ballast (A2), which is connected to the supply terminals (T1) of said light bulb (LT), as well as to one or more emergency lighting sources (S2), to least one battery (B1) and to a first electrical connector (T2) of a first electrical connection (CN1), said emergency electronic ballast (A2) being series-connected with a ballast of said light bulb (LT) and between said first electrical connector (T2) of said first electrical connection (CN1) and a second electrical connector (T1) of a second electrical connection of said threaded seat (CN2) and being able to control both the battery (B1) charging, by using the electric current flowing through said light bulb (LT), and said emergency lighting sources (S2), said first and second electrical connectors (T1 , T2) being connected together.

2. An adapter device (PA) according to claim 1 , characterized in that said light bulb (LT) is an incandescent light bulb or a compact fluorescent light bulb (CFL) or a LED light bulb.

3. An adapter device (PA) according to at least one of the preceding claims, characterized in that said emergency lighting sources (S2) are constituted by a set of emergency lighting LEDs (LDE1 , LDE2, LDEN).

4. An adapter device (PA) according to claim 1 , characterized in that said emergency ballast (A2) includes a controller device (CLDE), which comprises a microcontroller (M1) and which is supplied by said battery (B1), to which is parallel-connected, said controller device (CLDE) controlling the voltage across the power terminals (T1) of the light bulb (LT) to identify an emergency lighting condition, by recognizing it from a condition according to which a switch (I) of the electrical plant to which said light bulb (LT) is connected is off or is open, said controller device (CLDE) thus detecting the power mains upstream of said switch (I), so as to turn on said emergency lighting sources (S2), through said battery (B1) when a lack of said power mains upstream of said switch (I) is detected.

5. An adapter device (PA) according to at least one of the preceding claims, characterized in that said emergency lighting sources (S2) are turned off when the voltage of said battery (B1) falls below a predetermined minimum value.

6. An adapter device (PA) according to at least one of the preceding claims, characterized in that said emergency lighting condition is detected when the power mains voltage upstream of said switch (I) is lower than a predetermined threshold value.

7. An adapter device (PA) according to claim 4, characterized in that said microcontroller (M1) is able to modulate the average electrical current intensity which is absorbed by said battery (B1).

8. An adapter device (PA) according to at least one of the preceding claims, characterized in that said emergency lighting condition is inhibited for prefixed time periods, after certain user commands.

9. An adapter device (PA) according to at least one of the preceding claims, characterized in that said battery (B1) and said emergency ballast (A2) are housed inside a circular ring (AS) which is coaxial to said threaded seat (CN2), while said emergency lighting sources (S2) are mounted on the electrical circuit of said emergency ballast (A2) and are placed on an upper edge of said circular ring (AS), behind a protective transparent cover.

10. An adapter device (PA) according to at least one of the preceding claims, characterized in that said battery (B1) and said emergency ballast (A2) are housed inside said first electrical connector (CN1), while said emergency lighting sources (S2) are arranged on a upper edge of said second electrical connector in said threaded seat (CN2), behind a protective transparent cover (AS1).

11. An adapter device (PA) according to at least one of the preceding claims, characterized in that said adapter device (PA) is fixed to a threaded tube screwed into a threaded hole (F), which is placed at the bottom of said adapter device (PA), and said battery (B1) and said emergency battery (A2) are housed within the bottom of said adapter device (PA), while said emergency lighting sources (S2) are arranged on an upper edge of a circular ring (AS2), behind a protective transparent cover.