FR2549675A2 - Ignition device for fluorescent lighting tube lamp and lamp thus equipped - Google Patents

Abstract

a. Ignition device for fluorescent lighting tube lamp and lamp thus equipped. b. Characterised in that the ignition circuit 7 includes a diode pump R6, C3 formed of a diode, a resistor R6 and a capacitor C3 which is connected in parallel with the terminals N1, N2 of the circuit 7 for controlling the conducting of the Darlington setup T1, T2 short-circuiting the capacitor C1 for controlling the gate, the output of the setup being provided with a resistor R8 fixing the unblocking level of the setup T1, T2. c. The invention relates to fluorescent tube ignition devices.

Description

"Device for lighting a fluorescent tube lamp and lamp thus equipped".

 The present invention relates to an electronic device for instant lighting of a fluorescent lighting tube comprising a component with controlled conduction whose terminals are connected to the respective ends of the filaments of the fluorescent lighting tube, this component comprising in parallel a mounting. in series formed by a capacitor and a resistor as well as a control circuit connected to the trigger of the component to control the conduction, according to the first claim of the main patent.

 According to another characteristic, the main patent relates to a device of the above type in which the control circuit comprises a diode pump supplying control pulses via a threshold component which only becomes conductive when the voltage at the terminal of the capacitor of the diode pump exceeds a certain threshold, so as to no longer allow new attempts to ignite the tube.

 Such a control circuit operates analogically since the diode pump somehow ensures the "counting" of the number of ignition attempts.

 The present improvement proposes to create an electronic device for igniting a fluorescent lighting tube, according to the main patent in which the counting of the number of ignition attempts is done according to a digital process.

 To this end, the invention conce-rne an electronic device for the instant lighting of a fluorescent lighting tube, comprising a component with controlled conduction for connecting the filaments in series on the power supply and for priming the tube, with in parallel with the controlled component, a series connection of a capacitor and a resistor, a control circuit being connected to the trigger of the component to control its conduction, and a safety circuit controlling the switching off of the circuit command to prohibit operation after a number of ignition attempts according to claims 1 and 3 of the main patent, characterized in that the ignition circuit comprises a diode pump formed by a diode, a resistor and a capacitor connected to the circuit terminals to control the conduction of the assembly. Darlington short-circuits the trigger control capacitor, the output of the assembly being provided with a resistor fixing the n mounting release plate.

 This arrangement makes it possible to stabilize the operation of the circuit and in particular to make the triggering or the implementation of the inhibition of the trigger control, independent of multiple parameters such as manufacturing, ambient temperature, aging, etc. .

 The invention also relates to an electronic device for instant lighting of a fluorescent lighting tube, comprising a component with controlled conduction for connecting the filaments in series on the supply and for priming the tube, with in parallel with the controlled component , a series connection of a capacitor and a resistor, a control circuit being connected to the trigger of the component to control its conduction, and a safety circuit controlling the switching off of the control circuit, to prevent it operation after a certain number of ignition attempts, according to the main patent, characterized in that the control circuit has two inputs connected to the filaments in the manner of a choke, this circuit consisting of a control circuit of conduction of the component, of a frequency generator connected to the supply network to supply a frequency dependent on the frequency of the network, of a counting circuit receiving the frequency for counting at two counting states and controlling a safety circuit ensuring the short-circuiting of the pulses from the conduction control circuit to the trigger of the component by short-circuiting first the negative pulses then the negative and positive pulses or vice versa, depending on whether the counting circuit has reached its first counting state that its second counting state and a DC voltage generator providing the DC voltage so as to define a period of preheating of the filaments of the tube between substantially the time of closing of the power switch and the arrival of the signal corresponding to the first counting state, ~ period during which ignition is prohibited and a second period starting with the arrival of the first counting signal and ending with the arrival of the second signal counting, period during which ignition is possible and at the end of which neither the heating of the filaments nor the ignition is no longer possible before opening and closing the power contact again.

 The operation of this circuit is digital and no longer analog. This allows the preheating and ignition periods to be defined with great precision since this determination is made from the frequency of the electrical network; however in most of the countries, this frequency is very stable. In addition, the device makes it possible to prohibit any attempt to ignite during the preheating period, which is extremely advantageous since it avoids blackening and premature aging of the tube.

 According to a characteristic of the invention, the conduction control circuit consists of a capacitor which is charged by a resistance bridge and is connected to the trigger by a diac fixing the triggering threshold of the component, this circuit being connected between the two terminals of the circuit.

 According to another characteristic of the invention, the frequency generator consists of a transistor connected between the terminals of the circuit and the base of which is connected to a voltage divider formed by a resistor and a Zener diode, the output bu frequency signal being taken on the collector of the transistor.

 According to another characteristic of the invention, the counting circuit consists of a frequency divider receiving the frequency signal to supply two frequency signals, as well as two flip-flops each receiving one of the frequency signals to be ~ each once toggled by the flank of the first signal pulse and provide a toggle signal controlling the safety circuit.

 According to another characteristic of the invention, the DC voltage generator consists of a capacitor in parallel on a Zener diode to be charged through a resistor and a diode.

 According to another characteristic of the invention, the safety circuit is composed of two branches and of opposite conductivity, each branch being associated with one of the outputs of the counting circuit to be controlled by one or other of the signals count.

The present invention will be described in more detail with the aid of the accompanying drawings, in which
FIG. 1 is a block diagram of an electronic device for lighting a fluorescent lighting tube, according to the main patent,
- Figure 2 is a detailed diagram of a first variant of an electronic device for lighting a fluorescent tube, according to the present improvement.

FIG. 3 is a diagram of a second variant of the electronic device of a fluorescent tube, according to a second variant of the invention,
FIG. 4 formed from FIGS. 4a .... 4e, represents timing diagrams used to explain the operation of the invention,
- Figure 5 is a diagram of the integrated circuit forming part of the device according to the invention.

 FIG. 1 is a diagram of the assembly of an instantaneous ignition device for a fluorescent lighting tube, according to the main patent.

 As a reminder, this circuit intended to be connected to an alternative supply not shown, comprises a tube 1 connected by means of a choke 2 and a switch 4 to the supply network. The tube 1 is provided with two resistors a a2 The ignition control is provided by the device 5 surrounded by a rectangle. This device consists on the one hand of a component 6, the conduction of which is controlled by means of a trigger G receiving the control signals from an ignition and safety circuit 7. In parallel with the component 6, there is a series connection formed of a resistor R and 7 of a capacitor C2.

The purpose of circuit 7 is to make component 6 conductive to allow current to flow through the resistors a2. Every time the current flows
alternating supply, when the voltage is canceled,
component 6 hangs and at this time, choke 2
creates a voltage spike between resistorsal, a2
which allows to start the tube 1.

The purpose of the control circuit 7 is to control
the conductive state of component 6 and, after a certain
number of attempts, ignition failed without result,
circuit 7 also prohibits any new attempt
as long as switch 4 is closed. Through the opening,
then closing switch 4, the device can
re-order a series of ignition attempts.

Figure 2 is a more detailed diagram of a
interesting embodiment of the general device
shown in Figure 1, according to the main patent
with the improvement according to the present invention.

The ignition and safety circuit 5 is
only connected by terminals N1, N2 to the second terminals of resistors a1, a2 of tube 1, resistors
whose other terminals are connected to the power supply of the
sector, one directly, the other through
of choke 2 and switch 4.

In this example, component 6 is made up
by a thyristor whose trigger G is connected by
via a diac 8 and a diode D1 to a circuit
formed of capacitor C1 and resistors R1 R2, R3.

Darlington T1, T2 mounting is controlled by
circuit D rR, RRC. The diac 8 sets a threshold of 2 6 4 5 3
trigger of trigger G and diode D1 does not leave
pass that positive impulses.

The Darlington T1i T2 assembly is unlocked by the
diode pump D2. 26 C3 as soon as the release voltage
is reached across the capacitor. This diode pump
therefore ensures the analog counting of the half-waves of the
sector current. When the T1 T2 assembly is conductive,
it short-circuits the resistor R2 and the capacitor can no longer charge: the trigger G can no longer be commanded and the component 6 remains blocked. This situation remains as long as the switch 4 remains closed.

According to this improvement, at the output of the assembly T1,, T2 there is provided a resistor R8 intended to increase the triggering or tilting threshold of the assembly T1, T2 In fact, while, without this resistor R8, the rocker assembly, as is known for a voltage Vg, applied to its base and which is equal to VBE; however this voltage VBE is a function of the assembly
Darlington, temperature, aging, etc ...

Thanks to the resistor R8, the tripping voltage of the assembly T1, T2 corresponds to VB = VBE + R8 I
I being the current intensity in the resistor R8
We choose R8 I VBE, which makes triggering largely independent of the VBE voltage of the assembly.

It is clear that the choice of the value of R8 must be such that the voltage of the collector Ve, when the assembly T1, T2 is saturated, remains lower than the triggering voltage of the diac 8.

 FIG. 3 is a diagram both in principle and in detail of an embodiment in digital technique of the device for instantaneous ignition control of a fluorescent lighting tube. In this description, the same references will be used as in the various embodiments above and of the main patent to designate the same elements or similar elements.

 The digital technique used applies to the ignition and safety circuit 7. This technique consists in counting pulses formed from the mains current (frequency of 50 or 60 Hz) to calculate a warm-up time and a duration of ignition then cut the device to avoid premature wear and aging of the tube when ignition is not done immediately.

 The device 5 according to FIG. 3, is connected in the traditional way like a choke on the terminals N1, N21, that is to say in series on the resistors a11 a2. This therefore makes it possible to adapt this device like that of FIG. 2 on an already existing tube or even to integrate this device into a traditional manufacturing chain, of fluorescent tube lamps.

 The circuit 7 consists of a control circuit 100 for the conduction of the component 6, a frequency generator 101, a counting circuit 102, a safety circuit 103 and a voltage generator continues 104.

The control circuit ensures at each alternation of the supply current, the passage of a heating current through the resistors a1, a2, to ionize the gas in the tube and allow priming.

 The frequency generator 101 creates cadence pulses whose frequency f0 is a function of the frequency V of the supply voltage supplied by the network.

The cadence pulses fo are supplied to the counting circuit 102 which counts them from a given instant after the closing of the switch 2. The counting is done on two counting states (or 'frequencies) F1, F2 when one (F1) then the other (F2) counting states are reached, the circuit 102 sends instructions to the circuit 103 which first suppresses the negative pulses then the positive command pulses of the component 6 to define the period preheating and the priming period.

 In more detail, the conduction control circuit 100 consists of a diac 8 connected to the trigger G, a capacitor Clet of the voltage and charge division resistors of the capacitor R1, R2, R3 and a resistor R10 intended to define with diac 8 the trigger threshold of component 6.

 The frequency generator 101 consists of a transistor T10 connected between the lines L1, L2 of the terminals N11 N2.

The transistor T10 is connected to a collector resistor Rlo. Its base is connected to the junction of a Zener diode Z2 and a Roll resistor, the other terminal of Z2 being connected to Llet the other terminal of the resistor Rllest connected to line L2 by diode D4 (as with circuit 104).

The base of the transistor is biased by the voltage supplied by the DC voltage generator 104. The pulses of frequency fo corresponding to the frequency of the supply voltage, are taken from the collector of the transistor Tlo.

 The counting circuit 102 receives the pulses of frequency fo. This circuit consists of a frequency divider 120 providing two frequencies F1, F2 resulting from the frequency fo, and two flip-flops B1, B2 each receiving one of the frequencies F1, F2. The outputs Q1 'Q2 of the flip-flops B1, B2 attack the safety circuit 103 to define the heating period and the ignition period.

 The circuit 102 also comprises a reset circuit 121 which supplies a reset reset signal RESET to the flip-flops B11 B2. The reset circuit 121 consists of a transistor T25, of resistance R251 R26, R27 and of a capacitor C for, when the contact of the power switch is closed, apply the voltage of reset to flip-flops B1, B2.

 The assembly formed by the divider 120 and the flip-flops B1, B2, -constitutes a counting means since the flank of the first pulse of frequency F1 controls the emission of the signal Ql by the flip-flop B1: the circuit has therefore counted P1 pulses of frequency fo before sending the first pulse F1. I1 is the same for (F2 - B2 Q2).

 The safety circuit 103 is composed of two branches each formed by a transistor T111 T12 of the opposite type, the collector (T11) or the emitter (T12) of which are connected to the line L1, resistors R20, R21, R22, R23. and diodes Dlo, D11 ensuring the connection of the Tell transistors, T12 with the junction of the resistors R1, R2, R3 of the control circuit. The signals Q1, Q2 of the flip-flops polarize the transistors T11, T12 in such a way that throughout the duration of the signal Q1, the transistor T11 is switched on and lets the negative pulses pass, the transistor T, 2 being blocked. Q2 'the transistor T12 becomes conductive and lets the positive pulses pass.

 The DC voltage generator 104 consists of a Zener diode Z1 in parallel on a capacitor C3 and in series with a resistor R24 and a diode D4, the assembly being connected between the lines L1, L2; the DC voltage thus supplied is called V; this voltage is applied to the frequency generator 101 and to the counting circuit 102, 121.

The diagram in Figure 3 carries the references
A, B, C, D, E, F, G designating different functions.

These references have been taken up in the diagram of FIG. 5.

The timing diagrams of Figures 4A - 4E
FIG. 4A shows the sequence of positive and negative pulses which are applied to the trigger G when the circuit 103 does not intervene, that is to say when the transistors T111 Tl2 are blocked. Each pulse corresponds to an alternation of the sinusoidal supply voltage.

 FIG. 4B represents the frequency signal fo supplied by the generator 101. This signal is only formed by positive pulses.

 FIG. 4C represents the frequency signal F1.

In fact, only the leading edge of the first pulse of frequency F1 has been represented because this signal of frequency F1 is only useful in that it represents a change of state or voltage level (low level voltage - high level voltage) controlling the tilting of the rocker and consequently the unlocking of the Tell transistor. . From this moment, that is to say after time el, only the positive pulses are applied in G; these pulses can control the ignition of the tube 1.

FIG. 4D shows the frequency signal F2 as for the signal F1, only the change of state or level of this signal matters; after the change of state which occurs a time 82 after the end of time e1, the transistor
T12 is released and from this moment, no pulse can be applied to the trigger; component 6 remains permanently-blocked; to unlock it, you must open switch 4 again.

 During the preheating period el, the tube 1 cannot ignite and the current pulses passing through the filaments a11 a2 only serve to heat them to a temperature allowing their ignition later.

 During period 92, the control pulses of component 6 are only positive; the tube can only be lit during this period. Thus the invention creates a double security, the first controlling the duration of the preheating to avoid premature aging of the tube, the second limiting the ignition attempts.

 The diagram in FIG. 5 corresponds to an integrated circuit for the most part; the wafer 200 provided with the integrated circuit receives the components which are difficult to integrate, such as certain resistors and capacitor.

The connection points of this plate 200, namely
A, B, C, D, E, F, G are those shown in Figure 3.

 In general and depending on the quantities to be manufactured, the device will be produced in discrete components, in hybrid technique or in the form of an integrated circuit.

Claims (9)

R -E V E N D I C A T flO N S  10) Electronic device for instantaneous lighting of a fluorescent lighting tube, comprising a component with controlled conduction to connect the filaments (a1, a2) in series on the power supply and to start the tube, with in parallel to the component controlled1 a series connection of a capacitor (C2) and of a resistor (R7), control circuit (7) being connected to the trigger (G) of the component (6) to control its conduction, and a safety circuit controlling the switching off of the control circuit (7) to prohibit its operation after a certain number of ignition attempts, according to claims 1 and 3 of the main patent, characterized in that the ignition circuit (7) comprises a diode pump (D2, R6, C3) formed by a diode (D2), a resistor (R6) and a capacitor (C3) connected to the terminals 61, N2) of the circuit ( 7) to control the conduction of the Darlington circuit (Tl, T2) bypassing the trigger control capacitor (C1), the output of the assembly (T1, T2) being provided with a resistor (R8) fixing the level of release of the assembly (T1, T2).  20) Electronic device for instant lighting of a fluorescent lighting tube comprising a component with controlled conduction to connect the filaments (a1, a2) in series on the power supply and to initiate the tube, with the controlled component in parallel, a series connection of a capacitor (C2) and a resistor (R7), a control circuit (7) being connected to the trigger 8) of the component (6) to control its conduction, and a safety circuit controlling the switching off of the control circuit (7) to prohibit its operation after a certain number of ignition attempts, according to claims 1 and 3 of the main patent, characterized in that the control circuit (7) has two inputs (N1, N2), (-t1, L2) connected to the filaments (a1, a2) in the manner of a choke, this circuit (7) consisting of a conduction control circuit (100) of the component ( 6), a frequency generator (101) connected to the supply network (L1, L2) for r supply a frequency (fO) dependent on the frequency of the network, of a counting circuit (102) receiving the frequency (fO) to count with two counting states (F1, F2, 120, B1, B,) and command a safety circuit (103) ensuring the short-circuiting of the pulses from the conduction control circuit (100) to the trigger (G) of the component (6) by short-circuiting first the negative pulses then the negative and positive-pulses ~ or inversely depending on whether the counting circuit (102) has reached its first counting state (F1, B1, Q1) or its second counting state (F2, B2, Q2) and of a direct voltage generator (104) providing the continuous voltage, so as to define a period of preheating of the filaments (Q1 'Q2) of the tube (1) between substantially the moment of closing of the supply switch (4) and the arrival of the signal corresponding to the first counting state (F1, Q1) 'period during which ignition is prohibited and a second period beginning with the arrival of the first counting signal and ending with the arrival of the second counting signal, period during which ignition is possible and at the end of which neither the heating of the filaments nor the ignition is no longer possible before opening and closing the power contact (2) again.  30) Device according to claim 2, characterized in that the conduction control circuit (100) consists of a capacitor (C1) which is charged by a resistance bridge (R1, R2) and is connected to trigger (G ) by a diac (8) fixing the tripping threshold of the component (6), this circuit (100) being connected between the two terminals (N1, N2) of the circuit (5).  40) Device according to claim 2, characterized in that the frequency generator (101) consists of a transistor (T1o) connected between the terminals (N1, N2) of the circuit (7) and whose base is connected to a voltage divider formed by a resistor (R11) and a Zener diode Z2, the frequency signal output being taken from the du-transsistor collector (T10).  50) Device according to claim 2, characterized in that the counting circuit (102) - consists of a frequency divider (120) receiving the frequency signal (fO) to provide two frequency signals (F1, F2) as well that of two flip-flops (B1, 32> each receiving one of the frequency signals (F1, F2) to be each time switched by the flank of the first pulse of the signal (F1, F2) and supply a switching signal ( Q1 'Q2) controlling the safety circuit (103).  60) Device according to claim.2, characterized in that the DC voltage generator (106) consists of a capacitor (C3) in parallel on a Zener diode (Z1) to be charged through a resistor (R24) and a diode (D4).  70) Device according to claim 2, characterized in that the safety circuit (103) consists of two branches (T11, R20, R21, D12) and (T12, R22, R23, D11) of opposite conductivity, each branch being associated with one of the outputs (Q1 'Q2) - of the counting circuit to be - controlled by one or the other of the counting signals (F1, Q1; F21 Q2).  80) Device according to claim 7, characterized in that each branch consists of a transistor (T111 T12) whose collector-emitter path is mounted between one of the terminals (N1) of the circuit (7) and the trigger ( G) of component (6).  90) Device according to any one of claims 2 to 8, characterized in that the control circuit (7) is produced in the form of an integrated circuit provided with terminals (A, B, C, D, E, F , G) for the connection in particular of the components (C1, C21 C3, R1, R7) which are difficult to produce in the form of an integrated circuit.