CN101668374A - Lamp-lighting apparatus - Google Patents
Lamp-lighting apparatus Download PDFInfo
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- CN101668374A CN101668374A CN200910171146A CN200910171146A CN101668374A CN 101668374 A CN101668374 A CN 101668374A CN 200910171146 A CN200910171146 A CN 200910171146A CN 200910171146 A CN200910171146 A CN 200910171146A CN 101668374 A CN101668374 A CN 101668374A
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Abstract
An economical device for lighting lamps such as discharge tubes. The lamp-lighting apparatus has an inverter transformer, a switching circuit connected with the primary winding of the inverter transformer and acting to perform switching for converting a voltage from an input power supply, a shunt transformer connected in series with the secondary winding of the inverter transformer, lamps connected in series with the shunt transformers, and a control circuit for producing a control signal to control the switching performed by the switching circuit based on the voltages at the junctions of theshunt transformer and each of the lamps without directly detecting the voltage applied to the secondary winding of the inverter transformer. The number of protective circuits can be reduced. Consequently, the cost can be reduced.
Description
The application be that November 4, application number in 2005 are 200510115484.5 the applying date, denomination of invention divides an application for the application for a patent for invention of " lamp-enlightened device ".
Technical field
The present invention relates to lamp-enlightened device.
Background technology
Fig. 1 represents an example of discharge tube lamp-enlightened device in the past.The discharge tube lamp-enlightened device of Fig. 1 applies voltage V1 by the inverter that comprises switching circuit (inverter) to the primary coil of main transformer T100, produces voltage VMT in the second coil side of main transformer T100.One end of the secondary coil of main transformer T100 is connected on the end of the primary coil of shunt transformer (balancer) TB100 and secondary coil, the other end ground connection of the secondary coil of main transformer T100.On the other end of the primary coil of shunt transformer TB100, be connected with the end of discharge tube Lp100 such as cold-cathode tube, on the other end of the secondary coil of shunt transformer TB100, be connected with the end of discharge tube Lp102.Shunt transformer TB100 be the electric current that flows through discharge tube that causes for the property difference that suppresses by discharge tube difference, avoid the discharge tube of the different lamps that occur not working of starting characteristic because of each discharge tube, produce the device of voltage according to the difference between current of primary coil and secondary coil, be used to produce the voltage of opposite polarity in primary side and second coil side.The other end of discharge tube Lp100 and Lp102 is connected on the end of resistance R 100, the other end ground connection of resistance R 100.
In the prior art, in such discharge tube lamp-enlightened device, overvoltage Limiting circuit 101 and constant-current control circuit 102 have been used, above-mentioned overvoltage Limiting circuit 101 is used to make the secondary coil of main transformer T100 and primary coil and the secondary coil of shunt transformer TB100 not to be applied in overvoltage, and above-mentioned constant-current control circuit 102 is used to make the electric current homogenizing that flows into discharge tube Lp100 and Lp102.Therefore, resistance R 100 is imported into constant-current control circuit 102 with the voltage of the tie point of discharge tube Lp100 and Lp102, the output of the testing circuit 103 of the voltage between terminals of the primary coil of secondary coil voltage VMT, the shunt transformer TB100 of detection main transformer T100, and the output of the testing circuit 104 of the voltage between terminals of the secondary coil of detection shunt transformer TB100, be imported into overvoltage Limiting circuit 101.Switch by the switching circuit of the output control inverter of overvoltage Limiting circuit 101.
Because discharge tube needs high voltage when starting, therefore produce high voltage on shunt transformer TB100, main transformer T100.In addition, when certain discharge tube in action produces unusually, when becoming open circuit, on shunt transformer TB100, main transformer T100, produce high voltage.In order to prevent the withstand voltage destruction of shunt transformer TB100, main transformer T100, as mentioned above, overvoltage Limiting circuit 101 or protective circuit, voltage clamp circuit are set, the maximum voltage of restriction shunt transformer TB100 and main transformer T100.At this moment, there are the following problems, thereby have problems aspect shape, cost.
(1) protective circuit needs 2 systems.(1 system is the overvoltage Limiting circuit 101 at main transformer T100, and another system is the testing circuit 103,104 at shunt transformer TB100, and overvoltage Limiting circuit 101.)
(2) voltage that produces at the connecting portion of shunt transformer TB100 and discharge tube exceeds requiredly and increases, and wiring figure interval, parts rated value etc. are exceeded requiredly to be increased.
More particularly, the maximum VLAMPmax of the voltage VLAMP that produces at the connecting portion of shunt transformer TB100 and discharge tube, for the maximum VMTmax of the voltage VMT that produces on the secondary coil of main transformer T100 and the voltage VB that on shunt transformer TB100, produces maximum VBmax's and.That is VLAMPmax=VMTmax+VBmax.In addition, VLAMP need guarantee the voltage VLAMPSTRIKE that the bright lamp of discharge tube is required.On the other hand, because voltage VB is subjected to the difference of each discharge tube, the properties influence of shunt transformer TB100, so need make VMT can produce VLAMPSTRIKE in advance.Its result might become VLAMPmax=VLAMPSTRIKE+VBmax, needs wiring figure interval, the parts rated value of this voltage of ability.
Also disclose and the similar circuit of circuit shown in Figure 1 among the open communique 2004-0155596A1 of U. S. application.
In addition, in open communique 2005-93471A1 of U. S. application and the open communique 2005-93472A1 of U. S. application, disclose and have a plurality of balancing transformers, make the same annular flat weighing apparatus of electric current in the back light source system that constitutes by a plurality of lamps.The primary coil of the balancing transformer in this annular flat weighing apparatus is connected in series in respectively on 1 specific lamp, and all secondary coils connect into closed loop.Thus,, make the electric current of second coil side same, thereby make the drive current of lamp of primary side also same by the closed loop that forms by secondary coil.
The open communique 2004-0155596A1 of [patent documentation 1] U. S. application
The open communique 2005-93471A1 of [patent documentation 2] U. S. application
The open communique 2005-93472A1 of [patent documentation 3] U. S. application
Summary of the invention
Like this, in the prior art, have problems for above-mentioned reasons at aspects such as costs.
Therefore, the object of the present invention is to provide a kind of technology that is used at the lamp-enlightened device cutting down cost of lamps such as discharge tube.
Another object of the present invention is to provide a kind of technology that is used for improving fail safe at lamp-enlightened device.
A further object of the present invention is to provide a kind of technology of efficiently, reliably lamp being lighted at lamp-enlightened device of being used for.
In addition, other purpose of the present invention is to provide a kind of new technology that is used for making at lamp-enlightened device the brightness uniformity of lamp.
The lamp-enlightened device that the present invention's first scheme relates to has: inverter transformer; Switching circuit is connected on the primary coil of above-mentioned inverter transformer, is used to change the switch from the input power source voltage; Balancer is connected on the secondary coil of above-mentioned inverter transformer, is used to make the electric current homogenizing that flows into a plurality of lamps; And control circuit, based on in voltage that produces on the secondary coil of above-mentioned inverter transformer and the voltage sum correspondent voltage that on above-mentioned balancer, produces, generate the control signal of the switch of control said switching circuit.
Like this, by based on controlling with voltage that on the secondary coil of inverter transformer, produces and the voltage sum correspondent voltage that on balancing transformer, produces, the voltage that is greater than or equal to required voltage can not impose on parts, is being favourable aspect wiring figure and the parts cost.
In addition, also above-mentioned balancer can be connected in series between the secondary coil and lamp of inverter transformer, above-mentioned control circuit generates the control signal of the switch of control switch circuit based on the current potential of the tie point of balancer and lamp.Like this, directly do not detect, be controlled at the voltage that applies on the secondary coil of inverter transformer (main transformer), but the voltage of the tie point of detection, control balancer and lamp, thereby the protective circuit system can be cut down.And, only carry out such control and also can make the withstand voltage of inverter transformer and balancer move no problemly, and can make the bright reliably lamp of lamp.
In addition, also can above-mentioned balancing transformer be set to each lamp; And then comprise first testing circuit, detect and the voltage correspondent voltage that on the secondary coil of inverter transformer, produces; Second testing circuit, the maximum voltage correspondent voltage among the voltage that detects and in balancer, be responsible for producing on the part of each lamp; And the circuit that the output voltage of the output voltage of first testing circuit and second testing circuit is carried out add operation.For example, with dealing with the voltage condition that can not directly detect the tie point of balancer and lamp.
In addition, also can be that above-mentioned balancer has a plurality of transformers, the primary coil of each transformer is connected in series on the secondary coil of 1 load lamp and inverter transformer, and makes the secondary coil of this transformer and the secondary coil of other transformer connect into closed loop.And then also can make above-mentioned a plurality of transformer have three grades of coils, these three grades of coils produce and the voltage correspondent voltage that produces on primary coil.
The lamp-enlightened device that alternative plan of the present invention relates to has: inverter transformer; Switching circuit is connected on the primary coil of inverter transformer, is used to change the switch from the input power source voltage; Balancer is connected on the secondary coil of inverter transformer, is used to make the electric current homogenizing that flows into a plurality of lamps; And control circuit, based on the voltage that on balancer, produces, generate the control signal of the switch of control switch circuit; Above-mentioned balancer comprises the transformer with three grades of coils, detects the voltage that produces at above-mentioned balancer from three grades of coils.Thus,, also can detect and the primary coil correspondent voltage even can not dispose waiting under the situation of the capacitor that dividing potential drop uses for fear of discharge, and based on this voltage control lamp-enlightened device.
The lamp-enlightened device that third party's case of the present invention relates to has: inverter transformer; Switching circuit is connected on the primary coil of inverter transformer, is used to change the switch from the input power source voltage; Balancer is connected on the secondary coil of inverter transformer, is used to make the electric current homogenizing that flows into a plurality of lamps; And control circuit, based on be detected via balancer and with the voltage correspondent voltage that imposes on a plurality of lamps among maximum voltage, with the electric current that flows through above-mentioned lamp, whether detect lamp lights all, generation is used to make the control signal of the start-up mode end of moving under the condition different with common action, and exports to switching circuit.So-called start-up mode of moving under the condition different with common operation condition is meant the pattern of moving with the resonance frequency of the resonant circuit that for example forms on the secondary coil of inverter transformer.Thus, can also suitably judge the end of start-up mode.
In addition, also can be that above-mentioned control circuit comprises the circuit that carries out following action: by with the voltage correspondent voltage that imposes on above-mentioned a plurality of lamps among maximum voltage, whether each above-mentioned lamp is responsible in detection in above-mentioned balancer part is less than or equal to predetermined voltage with maximum voltage among the voltage of the tie point of above-mentioned lamp, and whether the summation of electric current that flows through all above-mentioned lamps is more than or equal to predetermined level.
In addition, also can be that above-mentioned balancer has a plurality of transformers, the primary coil of each transformer is connected in series on the secondary coil of 1 load lamp and inverter transformer, and the secondary coil of the secondary coil of this transformer and other transformer connects into closed loop.
The lamp-enlightened device that the cubic case of the present invention relates to has: one or more inverter transformers; First balancer comprises first transformer, and the primary coil of this first transformer is connected on the end of lamp specific among the secondary coil of above-mentioned one or more inverter transformers and a plurality of lamp, is used to make the electric current homogenizing that flows into these a plurality of lamps; Second balancer comprises second transformer, and the primary coil of this second transformer is connected on the other end of lamp specific among the secondary coil of above-mentioned one or more inverter transformers and the above-mentioned a plurality of lamp, is used to make the electric current homogenizing that flows into above-mentioned a plurality of lamps; And the device that the two ends of a plurality of lamps is provided anti-phase mutually voltage.And, the position that exists the secondary coil of the secondary coil of first transformer and second transformer to be connected in series.Like this,, can make the electric current homogenizing that flows through at the two ends of lamp, make the brightness uniformity of a plurality of lamps by first balancer and second balancer.
In addition, also can be to have a plurality of first transformers and a plurality of second transformer, first transformer each other, secondary coil is connected in series by the different relation of polarity, second transformer each other, secondary coil is connected in series by the different relation of polarity, and the secondary coil of the secondary coil of at least 1 first transformer and at least 1 second transformer is connected in series by the identical relation of polarity.
And, also can be that above-mentioned first balancer has a plurality of first transformers, the primary coil of each first transformer is connected in series on the secondary coil of 1 load lamp and one or more inverter transformers, and the secondary coil of this first transformer is connected on the terminal of opposed polarity of secondary coil of other any one first transformer in first balancer.In addition, also can be that second balancer has a plurality of second transformers, the primary coil of each second transformer is connected in series on the secondary coil of 1 load lamp and one or more inverter transformers, and the secondary coil of this second transformer is connected on the terminal of opposed polarity of secondary coil of other any one second transformer in second balancer.And, also can be that the secondary coil of the transformer in first balancer and the secondary coil of the transformer in second balancer connect into closed loop.
The lamp-enlightened device that the present invention's the 5th scheme relates to has: first inverter transformer; First switching circuit is connected on the primary coil of first inverter transformer, is used to change the switch from the first input power source voltage; First balancer is connected on the end separately of the secondary coil of first inverter transformer and a plurality of lamps, is used to make the electric current homogenizing that flows into these a plurality of lamps; Second inverter transformer; The second switch circuit is connected on the primary coil of second inverter transformer, is used to change from the second input power source voltage, makes and the anti-phase switch of output of first inverter transformer; Second balancer is connected on the other end separately of the secondary coil of second inverter transformer and a plurality of lamps, is used to make the electric current homogenizing that flows into these a plurality of lamps; Testing circuit detects the electric current that flows into a plurality of lamps; And control circuit, under the situation of variation that detects the electric current that flows into lamp by testing circuit, stop the switch of first switching circuit and second switch circuit more than or equal to predetermined level, perhaps carry out the electric current restriction.And first balancer and second balancer couple together.
The variation of the so-called electric current that flows into lamp is more than or equal to predetermined level, is meant when problem or inverter transformer having taken place problem has taken place because of any one lamp, by stopping action or carrying out electric current and limit and guarantee safety.
The technology of the bright circuit for lamp that also can above-mentioned first scheme to the of combination in any five schemes relates to.
The circuit that is used to realize above structure exists a plurality of, below enumerate object lesson, but the present invention is not limited to this.
According to the present invention, can be in the lamp-enlightened device of lamps such as discharge tube cutting down cost.
As another aspect of the present invention, can in lamp-enlightened device, improve fail safe.
And then, can in lamp-enlightened device, efficiently, reliably lamp be lighted as another aspect of the present invention.
In addition, another object of the present invention is in lamp-enlightened device, to make the brightness uniformity of lamp.
Description of drawings
Fig. 1 is the figure that represents the example of bright circuit for lamp in the past.
Fig. 2 is the figure of the bright circuit for lamp of expression first embodiment of the invention.
Fig. 3 is the figure that is used to illustrate the principle of first embodiment of the invention.
Fig. 4 is the figure of the effect of expression first embodiment of the invention.
Fig. 5 is the figure of the bright circuit for lamp of expression second embodiment of the invention.
Fig. 6 is the figure of the bright circuit for lamp of expression third embodiment of the invention.
Fig. 7 is the figure of the bright circuit for lamp of expression four embodiment of the invention.
(a)～(f) of Fig. 8 is the signal waveforms of action that is used to illustrate the bright circuit for lamp of four embodiment of the invention.
Fig. 9 is the figure of the bright circuit for lamp of expression fifth embodiment of the invention.
Figure 10 is the figure of the bright circuit for lamp of expression sixth embodiment of the invention.
Figure 11 is the figure of the bright circuit for lamp of expression seventh embodiment of the invention.
Figure 12 is the figure of the bright circuit for lamp of expression eighth embodiment of the invention.
Figure 13 is the figure of the bright circuit for lamp of expression ninth embodiment of the invention.
Embodiment
(first execution mode)
Fig. 2 represents the circuit example of the lamp-enlightened device that first execution mode relates to.The lamp-enlightened device that first execution mode relates to has: the inverter that comprises switching circuit, inverter transformer (main transformer) T1, shunt transformer (balancer) TB1, lamp Lp1 and Lp2 such as cold-cathode tube, resistance R 1, dividing potential drop and rectification circuit 10 and 11, rectification circuit 12, overvoltage Limiting circuit 13, constant-current control circuit 14, diode 15 and 16.Overvoltage Limiting circuit 13 has: comparator 131, the first reference voltage power supplys 132, MOSFETS1.Constant-current control circuit 14 has: comparator 141 and 144, the second reference voltage power supplys 142, triangular-wave generator 143.
Inverter is connected on the primary coil of inverter transformer T1, applies voltage V1 on the primary coil of this inverter transformer T1.Second coil side at inverter transformer T1 produces voltage VMT.One end of the secondary coil of inverter transformer T1 is connected on the end of the primary coil of shunt transformer TB1 and secondary coil.The other end ground connection of the secondary coil of inverter transformer T1.The other end of the primary coil of shunt transformer TB1 is connected on the end of lamp Lp1, and the other end of the secondary coil of shunt transformer TB1 is connected on the end of lamp Lp2.The other end of the other end of lamp Lp1 and lamp Lp2 is connected on the end of resistance R 1, the other end ground connection of resistance R 1.And the voltage of establishing the primary side of shunt transformer TB1 is VB1, and the voltage of second coil side is VB2.In addition, make the polarity of the primary coil of shunt transformer TB1 and secondary coil opposite.
The primary coil of shunt transformer TB1 and the tie point of lamp Lp1 are connected on dividing potential drop and the rectification circuit 10, and dividing potential drop and rectification circuit 10 are connected on the overvoltage Limiting circuit 13 via diode 15.The secondary coil of shunt transformer TB1 and the tie point of lamp Lp2 are connected on dividing potential drop and the rectification circuit 11, and dividing potential drop and rectification circuit 11 are connected on the overvoltage Limiting circuit 13 via diode 16.The tie point of lamp Lp1, Lp2 and resistance R 1 is connected on the rectification circuit 12, and rectification circuit 12 is connected on the constant-current control circuit 14.
In overvoltage Limiting circuit 13, the output of dividing potential drop and rectification circuit 10 and dividing potential drop and rectification circuit 11 via diode 15 or diode 16, is input to the side of the positive electrode input terminal of comparator 131.The side of the positive electrode terminal of reference voltage power supply 132 is connected on the negative side input terminal of comparator 131, the negative side terminal ground connection of reference voltage power supply 132.The output of comparator 131 is connected on the grid of MOSFETS1.The source ground of MOSFETS1, drain electrode is connected on the negative side input terminal of the comparator 144 in the constant-current control circuit 14.In addition, the output of rectification circuit 12 is connected on the negative side input terminal of the comparator 141 in the constant-current control circuit 14, is connected with the side of the positive electrode terminal of reference voltage power supply 142 on the side of the positive electrode input terminal of comparator 141.The negative side terminal ground connection of reference voltage power supply 142.The output of comparator 141 is connected on the negative side input terminal of comparator 144.Be connected with triangular-wave generator 143 on the side of the positive electrode input terminal of comparator 144.The output of comparator 144 is imported into inverter, changes the duty ratio (duty) of the switching circuit that is comprised in the inverter.
The action of lamp-enlightened device shown in Figure 2 below is described simply.Be applied in the voltage V1 on the primary coil of inverter transformer T1 according to the output of inverter, become VMT in second coil side, TB1 boosts or step-down by the shunt transformer, and imposes on lamp Lp1 and Lp2.The action of shunt transformer is the same with in the past shunt transformer, be for the electric current that flows through lamp that suppresses to bring by the difference of modulation characteristic difference, avoid producing the lamp of the lamp that do not work because of the difference of the starting characteristic of each lamp, and produce the device of voltage according to the difference between current of primary coil and secondary coil.More particularly, as shown in Figure 3, when establishing the not bright lamp of lamp Lp1, the bright lamp of lamp Lp2, lamp Lp1 is applied the voltage VLamp1=VMT+VB1 higher than voltage VMT by shunt transformer TB1, lamp Lp2 is applied the voltage VLamp2=VMT+VB2 lower than voltage VMT (at this, VB2 has negative value).In addition, in the example of Fig. 2, owing to have only 2 lamps, so VB1+VB2=0, among Fig. 2, VOVP=VMT+VB1=VMT-VB2.
A higher side in the voltage of overvoltage Limiting circuit 13 with the tie point of shunt transformer TB1 and lamp Lp1 or Lp2, compare with the output voltage (controlled target voltage) of reference voltage power supply 132, in the voltage of above-mentioned tie point under the higher situation of a side more than or equal to the output voltage of reference voltage power supply 132, the output of MOSFETS1 becomes ON (conducting), the negative side input terminal ground connection of the comparator 131 in the overvoltage Limiting circuit 13.On the other hand, in the voltage of above-mentioned tie point under the higher situation of a side less than the output voltage of reference voltage power supply 132, the output of MOSFETS1 becomes OFF (ending), and the output of the comparator 131 in the overvoltage Limiting circuit 13 outputs to the negative side input terminal of comparator 144 at this point.In constant-current control circuit 14, take out the electric current that flows into lamp Lp1 and Lp2 by resistance R 1, and be input to comparator 141, the output voltage with reference voltage power supply 142 in comparator 141 compares.If the electric current that flows into lamp Lp1 and Lp2 is less than benchmark, then the output of comparator 141 increases, and in the comparison that the triangular wave with comparator 144 carries out, generates the elongated control signal of conducting duty ratio.That is, control, make to flow into the current constant of lamp, and control, make the voltage of tie point of shunt transformer TB1 and lamp Lp1 or Lp2 be less than or equal to predetermined voltage (VOVP by overvoltage Limiting circuit 13 and constant-current control circuit 14.Specifically, be voltage after the maximum VLAMPSTRIKE of bright modulating voltage or VLAMPSTRIKE add necessary nargin).
At this, after Fig. 2 and Fig. 3 at length studied, obtain following result.Promptly,
VMT+VBmax≤VOVP (1)
(VBmax be among the voltage that applies on the shunt transformer maximum voltage (on the occasion of).)
VMT+VBmin＝VLAMPONmin (2)
(VLAMPONmin works as the lamp of being lighted the minimum value of its driving voltage is arranged when a plurality of.
VBmin is the minimum voltage (negative value) among the voltage that applies on the shunt transformer)
VB1+VB2＝0 (3)
Can get according to formula (1):
VMT≤VOVP-VBmax (1)′
According to formula (3) VBmax＞0 (perhaps can only be all VB=0) as can be known, therefore can get:
VMT≤VOVP (4)
Therefore, about inverter transformer T1, as long as withstand voltage just no problem more than or equal to VOVP.
In addition, can get according to formula (2):
VMT＝VLAMPONmin-VBmin (2)′
According to formula (3) VBmin＜0 as can be known, therefore can get:
VMT＞VLAMPONmin (5)
When VMT was less than or equal to it, all lamps all extinguished.
And then, can get according to formula (1):
VBmax≤VOVP-VMT (1)″
Can get according to formula (5):
VBmax≤VOVP-VLAMPONmin (6)
In addition, can get according to formula (2):
VBmin=VLAMPONmin-VMT takes absolute value to both sides, then has:
|VBmin|＝VMT-VLAMPONmin (2)″
Can get according to formula (4):
|VBmin|≤VOVP-VLAMPONmin (7)
According to formula (6) and formula (7) as can be known, as long as shunt transformer TB1 withstand voltage just no problem more than or equal to VOVP-VLAMPONmin.
At this, when the maximum of the bright modulating voltage of establishing lamp was VLAMPSTRIKE, the result as shown in Figure 4.Promptly, in the past, the maximum of the voltage VMT that generates in the second coil side of inverter transformer T1 is VLAMPSTRIKE, and the maximum that is applied to the voltage on the shunt transformer TB1 is VBmax, and the maximum of the voltage of the tie point of shunt transformer TB1 and lamp is VLAMPSTRIKE+VBmax.But, according to present embodiment, the maximum of the voltage VMT that generates in the second coil side of inverter transformer T1 is VLAMPSTRIKE, the maximum that is applied to the voltage on the shunt transformer TB1 is VLAMPSTRIKE-VLAMPONmin, and the maximum of the voltage of the tie point of shunt transformer TB1 and lamp is VLAMPSTRIKE.Therefore therefore, the voltage ratio of the tie point of shunt transformer TB1 and lamp was low in the past, can reduce withstand voltagely, can use the transformer of cheapness, can also reduce and the wiring figure of substrate between the such safety issue of discharge.That is the layout that, helps wiring figure.In addition, in the illustrated example, represented that the shunt transformer is that 1, lamp are 2 example, still, also is applicable to the situation that is made the bright lamp of a plurality of lamps by a plurality of shunt transformers in the above.For example, make under the situation of N the bright lamp of lamp,, expanding into VB1+VB2+...+VBN=0 about formula (3) by N shunt transformer, still, in fact with top identical.
Like this, in the present embodiment,, detect voltage VMT+VBmax at the tie point of shunt transformer TB1 and lamp Lp1 or Lp2.Then, the voltage VMT+VBmax of control connection point makes it be less than or equal to predetermined voltage (specifically, be after the maximum VLAMPSTRIKE of bright modulating voltage or VLAMPSTRIKE add necessary nargin voltage).Thus, control can be reduced the withstand voltage of transformer by simplification.
(second execution mode)
Fig. 5 represents the circuit example of the lamp-enlightened device that second execution mode relates to.The lamp-enlightened device that second execution mode relates to is the distortion of the lamp-enlightened device that relates to of first execution mode, and the part of the balancer 17 among Fig. 5 is different with first execution mode.Balancer 17 comprises transformer TB1a and TB1b.Transformer TB1a and TB1b make second coil side produce transformer with the voltage of the voltage homophase of primary coil.And, the first terminal of the primary coil of transformer TB1a is connected on the first terminal of secondary coil of inverter transformer T1, and second terminal of the primary coil of transformer TB1a is connected on the input terminal of the first terminal of lamp Lp1 and dividing potential drop and rectification circuit 10.Equally, the first terminal of the primary coil of transformer TB1b is connected on the first terminal of secondary coil of inverter transformer T1, and second terminal of the primary coil of transformer TB1b is connected on the input terminal of the first terminal of lamp Lp2 and dividing potential drop and rectification circuit 11.The first terminal of the secondary coil of transformer TB1a is connected on second terminal of secondary coil of transformer TB1b, and the first terminal of the secondary coil of transformer TB1b is connected on second terminal of secondary coil of transformer TB1a.That is, transformer TB1a is connected the terminal of opposed polarity with the secondary coil of transformer TB1b, constitutes closed loop.Like this, because to flow through transformer TB1a identical with the electric current of the secondary coil of transformer TB1b, drive current primary coil, lamp Lp1 and Lp2 that therefore flows through transformer TB1a and transformer TB1b is also identical.That is, the brightness of lamp Lp1 and Lp2 is homogenized.
In addition, because the structure of the part except balancer 17 is identical with execution mode 1 with action, therefore omit explanation.
(the 3rd execution mode)
Fig. 6 represents the circuit example of the lamp-enlightened device that the 3rd execution mode relates to.The lamp-enlightened device that the 3rd execution mode relates to is the variation of the lamp-enlightened device that relates to of first and second execution modes.In the present embodiment, primary coil is connected on the lamp, secondary coil constitutes closed loop, and be provided with for diode 20a and 20b, dividing potential drop and rectification circuit 18 and voltage adder computing circuit 19 on three grades of coils that detect the transformer TB1c and the TB1d that are provided with three grades of coils at the voltage that produces on the primary coil, are connected transformer TB1c and TB1d, replace the shunt transformer TB1 of Fig. 2 or balancer 17, dividing potential drop and rectification circuit 10 and 11, the diode 15 and 16 of Fig. 5.Transformer TB1c and TB1d make secondary coil and three grades of coils produce voltage with the voltage homophase of primary coil.
The first terminal of the primary coil of transformer TB1c is connected on the first terminal of secondary coil of transformer T1, and second terminal of the primary coil of transformer TB1c is connected on the first terminal of lamp Lp1.The first terminal of the primary coil of transformer TB1d is connected on the first terminal of secondary coil of transformer T1, and second terminal of the primary coil of transformer TB1d is connected on the first terminal of lamp Lp2.The first terminal of the secondary coil of transformer TB1c is connected on second terminal of secondary coil of transformer TB1d, and the first terminal of the secondary coil of transformer TB1d is connected on second terminal of secondary coil of transformer TB1c.That is, the terminal of the opposed polarity of the secondary coil of transformer TB1c and TB1d is connected, and has constituted closed loop.Like this, because it is identical to flow through the electric current of secondary coil of transformer TB1c and TB1d, drive current primary coil, lamp Lp1 and Lp2 that therefore flows through transformer TB1c and TB1d is also identical.That is, the brightness of lamp Lp1 and Lp2 is homogenized.This part is identical with second execution mode.
On the other hand, the input terminal of dividing potential drop and rectification circuit 18 is connected on the first terminal of secondary coil of transformer T1.Detect and the VMT correspondent voltage by dividing potential drop and rectification circuit 18.In addition, the first terminal of three grades of coils of transformer TB1c is connected on the anode of diode 20a, the second terminal ground connection.Equally, the first terminal of three grades of coils of transformer TB1d is connected on the anode of diode 20b, the second terminal ground connection.The negative electrode of diode 20a and 20b links to each other, and is connected on the input terminal of voltage adder computing circuit 19.Maximum voltage VBmax correspondent voltage among the voltage VB2 that occurs on the input terminal of voltage adder computing circuit 19 with the primary coil of the voltage VB1 of the primary coil of transformer TB1c and transformer TB1d.Particularly in the primary side short circuit of transformer TB1c or TB1d, perhaps lamp Lp1 or Lp2 etc. take place under the unbalanced situation of the electric current of the primary side of transformer TB1c and TB1d, big threshold voltage to occur unusually.Therefore, in voltage adder computing circuit 19, as with the VMT correspondent voltage and with the add operation result's of VBmax correspondent voltage VMT+VBmax, be output to overvoltage Limiting circuit 13.
Following action is identical with first, second execution mode with structure.In first, second execution mode, each lamp is provided with dividing potential drop and rectification circuit, but, owing to want the voltage of dividing potential drop very high, therefore must use high withstand voltage capacitor, and,, therefore can not adopt the such circuit of first and second execution modes sometimes because high voltage circuit waits restriction many to distance between parts.In this case, use like this transformer TB1c with three grades of coils and TB1d, and diode 20a and 20b, then be not easy to produce problem as described above if resemble present embodiment.On the other hand, owing to detect the voltage identical, therefore play the effect identical with first, second execution mode with first, second execution mode with voltage adder operation circuit 19.That is, the brightness of lamp Lp1 and Lp2 is homogenized, can reduce the withstand voltage of transformer, uses cheap transformer.
(the 4th execution mode)
Fig. 7 represents the circuit example of the lamp-enlightened device that the 4th execution mode relates to.The lamp-enlightened device that the 4th execution mode relates to has: the inverter that comprises switching circuit, inverter transformer T2, shunt transformer TB11～TB1n, dividing potential drop and rectification circuit 22～2n, lamp Lp11～Lp1n, resistance R 21, modulating voltage detects with comparator 26, lamp current detects with comparator 27, AND circuit (with circuit) 28, control circuit 29.Second coil side at inverter transformer T2, constituted resonant circuit 21 by parasitic capacitance between leakage composition, resonant capacitor and the lamp of the second coil side of inverter transformer T2 and the parasitic capacitance between lamp and the panel, this resonant circuit 21 has the resonance frequency higher than the switching frequency of switching circuit.
Inverter is connected on the primary coil of inverter transformer T2.One end of the secondary coil of inverter transformer T2 is connected on the end of secondary coil of an end, shunt transformer TB1n of secondary coil of an end, shunt transformer TB12 of the primary coil of shunt transformer TB11 and secondary coil.The other end ground connection of the secondary coil of inverter transformer T2.The other end of the primary coil of shunt transformer TB11 is connected on the lamp Lp11, and the other end of secondary coil is connected on the end of primary coil of shunt transformer TB12.The other end of the primary coil of shunt transformer TB12 is connected on the lamp Lp12, and the other end of secondary coil is connected on the end of primary coil of shunt transformer TB1n.The other end of the primary coil of shunt transformer TB1n is connected on the lamp Lp13, and the other end of the secondary coil of shunt transformer TB1n is connected on the lamp Lp1n.The other end of lamp Lp11～1n is connected on the end of resistance R 21, the other end ground connection of resistance R 21.
The tie point of shunt transformer TB11 and lamp Lp11 is connected on dividing potential drop and the rectification circuit 22, the tie point of shunt transformer TB12 and lamp Lp12 is connected on dividing potential drop and the rectification circuit 23, the primary coil of shunt transformer TB1n and the tie point of lamp Lp13 are connected on dividing potential drop and the rectification circuit 24, and the secondary coil of shunt transformer TB1n and the tie point of lamp Lp1n are connected on dividing potential drop and the rectification circuit 2n.In this dividing potential drop and rectification circuit 22～2n, capacitor C 1, C2 are connected in series, the end ground connection of C2.On the tie point of capacitor C 1 and capacitor C 2, be connected with the negative electrode of diode D2, the plus earth of diode D2, equally, be connected with the anode of diode D1 on the tie point of capacitor C 1 and capacitor C 2, the negative electrode of diode D1 becomes the output of dividing potential drop and rectification circuit 22～2n.The output of such dividing potential drop and rectification circuit 22～2n is output to modulating voltage and detects with comparator 26.In addition, the tie point of lamp Lp11～Lp1n and resistance R 21 links to each other with comparator 27 with the lamp current detection.
Modulating voltage detects the output that detects with comparator 27 with the output of comparator 26 and lamp current and is imported into AND circuit 28, and the output of AND circuit 28 is connected to control circuit 29.The switch of the switching circuit that control circuit 29 control inverters are comprised at this, is implemented following control: when start-up mode, frequency is brought up to the resonance frequency of resonant circuit, when start-up mode finishes, turn back to common switching frequency.Can not access to a certain degree gain owing to do not bring up to resonance frequency yet, therefore be set at the frequency that is not resonance frequency sometimes yet.
The action of circuit shown in Figure 7 is described with Fig. 8.At first, when lamp-enlightened device like that be ON shown in Fig. 8 (a), it was OFF that modulating voltage detects the result who carries out with computing with the output of comparator 27 with the output of comparator 26 and lamp current detection.AND circuit 28 be output as OFF during, control circuit 29 is interpreted as start-up mode, the switching frequency of the switching circuit of inverter is set at the resonance frequency of resonant circuit.In order to carry out soft start, the output voltage of inverter increases gradually.Like this, shown in Fig. 8 (b), the voltage (modulating voltage) of the tie point of shunt transformer TB11～1n and lamp Lp11～1n increases gradually, and the output voltage of dividing potential drop and rectification circuit 22～2n also increases gradually.Because modulating voltage is an alternating voltage, therefore, in (b) of Fig. 8, face of land oscillography shape broadens up and down.In addition, the ceiling voltage among the output voltage of dividing potential drop and rectification circuit 22～2n is input to modulating voltage detection comparator 26.And, when surpassing at modulating voltage, any one the output voltage (absolute value) of dividing potential drop and rectification circuit 22～2n detects with in the comparator 26 during predefined voltage detecting usefulness threshold value 61, shown in Fig. 8 (d), the output that modulating voltage detects with comparator 26 becomes ON (low active).When having the lamp of bright lamp not, the output voltage of dividing potential drop and rectification circuit 22～2n height during than the bright lamp of all lamps, so setting voltage detects usefulness threshold value 61, makes it possible to detect such state.
In addition, lamp current detects with comparator 27, takes out the whole electric currents (lamp current) that flow into lamp Lp11～1n with resistance R21, and lamp current also increases gradually because of soft start.Shown in Fig. 8 (c), when surpassing at lamp current, this lamp current detects when predefined current detecting is with threshold value 62 in the comparator 27, and shown in Fig. 8 (e), the lamp current detection becomes high level with the output of comparator 27.
In the stage that begins like this to start, if only observe modulating voltage detect output with comparator 26, then start-up mode begin postpone.But, owing to flow through lamp current at first hardly, therefore lamp current detects and is output as low level state with comparator 27, if the Assembled lamp voltage detecting detects the output of using comparator 27 with the output and the lamp current of comparator 26, then can begin start-up mode from the stage that lamp-enlightened device becomes ON.Under start-up mode, produce higher voltage by resonant circuit in the second coil side of inverter transformer T2, make the bright in early days lamp of lamp.Therefore, if become start-up mode in early days, then can expect bright lamp more early.Lamp current detects to be set at modulating voltage with threshold value 62 and detects after output with comparator 26 becomes low level, and lamp current is above this lamp current detection threshold value.
When the whole bright lamp of lamp, shown in Fig. 8 (b), modulating voltage reduces.And after using threshold value 61 less than voltage detecting, shown in Fig. 8 (d), the output that modulating voltage detects with comparator 26 becomes high level.That is, shown in Fig. 8 (e), the output that lamp current detects with comparator 27 becomes high level, so the output of AND circuit 28 becomes high level shown in Fig. 8 (f), carries out from the switching of start-up mode to operational mode (normal mode).Like this, after having confirmed the bright lamp of lamp, transfer to operational mode, therefore, can suitably finish inefficient start-up mode.In control circuit 29,, detect transfer, and make the switching frequency of switching circuit turn back to common frequency to operational mode according to the output of AND circuit 28.
In addition, when also not indicating the end of start-up mode, might be some lamp existing problems through the scheduled time, automatically transfer to operational mode at this.
By such processing, can suitably switch start-up mode and the operational mode of using resonance to improve the voltage that lamp is applied.
(the 5th execution mode)
Fig. 9 represents the circuit example of the lamp-enlightened device that the 5th execution mode relates to.The lamp-enlightened device that the 5th execution mode relates to is the distortion of the lamp-enlightened device of the 4th execution mode, is provided with the balancer 30 that comprises transformer TB11a～TB1na, replaces shunt transformer TB11～TB1n.Transformer TB11a～TB1na produces the voltage with the voltage homophase of primary coil on secondary coil.Balancer 30 has the structure identical with the balancer that illustrates in second execution mode.
That is, the first terminal of the primary coil of transformer TB11a is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB11a is connected on lamp Lp11 and dividing potential drop and the rectification circuit 22.Equally, the first terminal of the primary coil of transformer TB12a is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB12a is connected on lamp Lp12 and dividing potential drop and the rectification circuit 23.The first terminal of the primary coil of transformer TB13a is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB13a is connected on lamp Lp13 and dividing potential drop and the rectification circuit 24.The first terminal of the primary coil of transformer TB1na is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB1na is connected on lamp Lp1n and dividing potential drop and the rectification circuit 2n.And the first terminal of the secondary coil of transformer TB11a is connected on the first terminal of secondary coil of transformer TB1na, and second terminal of the secondary coil of transformer TB11a is connected on the first terminal of secondary coil of transformer TB12a.Equally, second terminal of the secondary coil of transformer TB12a is connected on the first terminal of secondary coil of transformer TB13a, and second terminal of the secondary coil of transformer TB13a is connected on the first terminal of secondary coil of not shown transformer TB14a.In addition, second terminal of the secondary coil of transformer TB1 (n-1) a is connected on the first terminal of secondary coil of transformer TB1na.
That is, the terminal of the opposed polarity of the secondary coil of transformer TB11a and TB1na couples together, and constitutes closed loop.Like this, owing to the electric current of the secondary coil that flows through transformer TB11a and TB1na is identical, drive current primary coil, lamp Lp11～Lp1n that therefore flows through transformer TB11a and TB1na is also identical.That is, the brightness of lamp Lp11～Lp1n is homogenized.
Structure in addition is identical with the lamp-enlightened device of the 4th execution mode with action, omits explanation.
(the 6th execution mode)
Figure 10 represents the circuit example of the lamp-enlightened device that the 6th execution mode relates to.The lamp-enlightened device that the 6th execution mode relates to is the distortion of the lamp-enlightened device of the 5th execution mode, is provided with the balancer 30a that comprises capacitor C B1～CBn, replaces shunt transformer TB11～TB1n.The end of capacitor C B1 is connected on the transformer T2 via resonant circuit 21, and the other end of capacitor C B1 is connected on the first terminal of lamp Lp11.The end of capacitor C B2 is connected on the transformer T2 via resonant circuit 21, and the other end of capacitor C B2 is connected on the first terminal of lamp Lp12.The end of capacitor C B3 is connected on the transformer T2 via resonant circuit 21, and the other end of capacitor C B3 is connected on the first terminal of lamp Lp13.And the end of capacitor C B1 is connected on the transformer T2 via resonant circuit 21, and the other end of capacitor C Bn is connected on the first terminal of lamp Lp1n.
Such structure and the 4th, the 5th execution mode are the same, also can suitably switch start-up mode and the operational mode of using resonance to improve the voltage that lamp is applied.
(the 7th execution mode)
Figure 11 represents the circuit example of the lamp-enlightened device that the 7th execution mode relates to.The lamp-enlightened device that the 7th execution mode relates to is the distortion of the lamp-enlightened device of the 5th execution mode, be provided with balancer 30b with transformer TB11b～TB1nb, replace shunt transformer TB11～TB1n, and be provided with diode D3～D6, replace dividing potential drop and rectification circuit 22～2n.In transformer TB11b～TB1nb, on secondary coil and three grades of coils, produce voltage with the voltage homophase of primary coil.
That is, the first terminal of the primary coil of transformer TB11b is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB11b is connected on the lamp Lp11.Equally, the first terminal of the primary coil of transformer TB12b is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB12b is connected on the lamp Lp12.The first terminal of the primary coil of transformer TB13b is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB13b is connected on the lamp Lp13.The first terminal of the primary coil of transformer TB1nb is connected on the inverter transformer T2 via resonant circuit 21, and second terminal of the primary coil of transformer TB1nb is connected on the lamp Lp1n.The first terminal of the secondary coil of transformer TB11b is connected on second terminal of secondary coil of transformer TB1nb, and second terminal of the secondary coil of transformer TB11b is connected on the first terminal of secondary coil of transformer TB12b.Equally, second terminal of the secondary coil of transformer TB12b is connected on the first terminal of secondary coil of transformer TB13b, and second terminal of the secondary coil of transformer TB13b is connected on the first terminal of secondary coil of not shown transformer TB14b.In addition, second terminal of the secondary coil of transformer TB1 (n-1) b is connected on the first terminal of secondary coil of transformer TB1nb.
That is, the secondary coil of transformer TB11b and TB1nb, the terminal of its opposed polarity couples together, and constitutes closed loop.Like this, owing to the electric current of the secondary coil that flows through transformer TB11b and TB1nb is identical, drive current primary coil, lamp Lp11～Lp1n that therefore flows through transformer TB11b and TB1nb is also identical.That is, the brightness of lamp Lp11～Lp1n is homogenized.
In addition, the first terminal of three of transformer TB11b grades of coils is connected on the anode of diode D3.The second terminal ground connection of three grades of coils of transformer TB11b.The first terminal of three grades of coils of transformer TB12b is connected on the anode of diode D4, the second terminal ground connection of three grades of coils of transformer TB12b.The first terminal of three grades of coils of transformer TB13b is connected on the anode of diode D5.The second terminal ground connection of three grades of coils of transformer TB13b.The first terminal of three grades of coils of transformer TB1nb is connected on the anode of diode D6.The second terminal ground connection of three grades of coils of transformer TB1nb.The negative electrode of diode D3～D6 is connected to each other, and is connected the modulating voltage detection with on the input terminal of comparator 26.
On three grades of coils of transformer TB11b～TB1nb, produce voltage correspondent voltage with primary coil.Link together owing to be connected the negative electrode of the diode D3～D6 on three grades of coils of this transformer TB11b～TB1nb, therefore be created in the maximum voltage of the voltage that produces on three grades of coils of transformer TB11b～TB1nb, promptly produce with the primary coil correspondent voltage among maximum voltage.When adopting such circuit, different with the 4th～the 6th execution mode, detection be not modulating voltage.But the voltage of detection is and the modulating voltage correspondent voltage, if setting threshold suitably then becomes the action same with the 5th execution mode.
In addition, in the 5th and the 6th execution mode, each lamp is provided with dividing potential drop and rectification circuit, but, owing to want the voltage of dividing potential drop very high, therefore must use high withstand voltage capacitor, in addition, therefore because high voltage circuit is many to the restriction of distance between parts etc., can not adopt the such circuit of the 5th and the 6th execution mode sometimes.At this moment,, use transformer TB11b and TB1nb and diode D3～D6, then problem as described above can not take place with three grades of coils if resemble present embodiment like this.Three grades of coils also can detect the variation of the voltage of the primary coil that produces according to modulating voltage, can detect the non-equilibrium state of modulating voltage in modulating voltage detects with comparator 26 via diode D3～D6.
(the 8th execution mode)
Figure 12 represents the circuit example of the lamp-enlightened device that the 8th execution mode relates to.The lamp-enlightened device that the 8th execution mode relates to has: first inverter that comprises switching circuit, second inverter that comprises switching circuit, the first inverter transformer T3, the second inverter transformer T4 has the shunt transformer TB21～TB2n of one to three grade of coil, shunt transformer TB31～TB3n with one to three grade of coil, diode D11～D1n, diode D21～D2n, lamp Lp31～Lp3n, comparator 31, control circuit 32.Shunt transformer TB31～TB3n produces the voltage with the voltage homophase of primary coil on secondary coil and three grades of coils.
First inverter is connected on the primary coil of the first inverter transformer T3.The circuit that is fenced up by the single-point line that comprises this first inverter is a main circuit.One end of the secondary coil of the first inverter transformer T3 is connected on the end of secondary coil of an end, shunt transformer TB2n of secondary coil of an end, shunt transformer TB22 of the primary coil of shunt transformer TB21 and secondary coil.The other end ground connection of the secondary coil of the first inverter transformer T3.The other end of the primary coil of shunt transformer T21 is connected on the lamp Lp31, and the other end of secondary coil is connected on the end of primary coil of shunt transformer T22.The other end of the primary coil of shunt transformer T22 is connected on the lamp Lp32, and the other end of secondary coil is connected on the end of primary coil of shunt transformer T2n.The other end of the primary coil of shunt transformer T2n is connected on the lamp Lp3n, and the other end of the secondary coil of shunt transformer T2n is connected on the end of secondary coil of shunt transformer T3n.
Second inverter is connected on the primary coil of the second inverter transformer T4.The circuit that is fenced up by the single-point line that comprises this second inverter is from circuit.One end of the secondary coil of the second inverter transformer T4 is connected on the other end of secondary coil of an end, shunt transformer TB3n of secondary coil of an end, shunt transformer TB32 of the primary coil of shunt transformer TB31 and secondary coil.The other end ground connection of the secondary coil of the second inverter transformer T4.The other end of the primary coil of shunt transformer TB31 is connected on the lamp Lp31, and the other end of secondary coil is connected on the end of primary coil of shunt transformer TB32.The other end of the primary coil of shunt transformer TB32 is connected on the lamp Lp32, and the other end of secondary coil is connected on the primary coil of shunt transformer TB3n.The other end of the primary coil of shunt transformer TB3n is connected on the lamp Lp3n, and the other end of the secondary coil of shunt transformer TB3n is connected on the end of secondary coil of shunt transformer TB2n.Like this, lamp Lp31～Lp3n is by differential driving.That is, in first inverter and second inverter, phase place is carried out 180 ° of counter-rotatings, and produces vibration.In addition, the secondary coil of shunt transformer TB21～TB2n, the terminal of its opposed polarity interconnects each other.Equally, the secondary coil of shunt transformer TB31～TB3n, the terminal of its opposed polarity interconnects each other.And, the secondary coil of the secondary coil of shunt transformer TB2n and shunt transformer TB3n, the terminal of its same polarity links together.
In addition, an end of three grades of coils of shunt transformer TB21 is connected on the anode of diode D11, other end ground connection.The negative electrode of diode D11 is input to comparator 31.One end of three grades of coils of shunt transformer TB22 is connected on the anode of diode D12, other end ground connection.The negative electrode of diode D12 is input to comparator 31.One end of three grades of coils of shunt transformer TB2n is connected on the anode of diode D1n, other end ground connection.The negative electrode of diode D1n is input to comparator 31.One end of three grades of coils of shunt transformer TB31 is connected on the anode of diode D21, other end ground connection.The negative electrode of diode D21 is input to comparator 31.One end of three grades of coils of shunt transformer TB32 is connected on the anode of diode D22, other end ground connection.The negative electrode of diode D22 is input to comparator 31.One end of three grades of coils of shunt transformer TB3n is connected on the anode of diode D2n, other end ground connection.The negative electrode of diode D2n is input to comparator 31.
The output of comparator 31 is imported into control circuit 32, and first and second inverters are controlled in the output of control circuit 32.
Like this, not only shunt transformer TB21～2n is connected in main circuit, shunt transformer TB31～3n is being connected in circuit, and they all are connected.Therefore move, make that the electric current that flows into lamp Lp31～Lp3n is even.Therefore, the brightness at the two ends of lamp Lp31～Lp3n is also homogenized.In the bright circuit for lamp of Figure 12, three grades of coils of shunt transformer TB21～TB2n and shunt transformer TB31～TB3n are the devices that detect the voltage that produces on each shunt transformer, and this voltage signal is connected to diode, and is input to comparator 31.
If for example between the terminal of the secondary coil of the first inverter transformer T3 of main circuit because of short circuits such as the people contact, then the output voltage of the first inverter transformer T3 reduces.Like this, because the second inverter transformer T4 and first inverter transformer T3 driving in parallel from circuit, and with identical duty ratio action, therefore the output voltage of the first inverter transformer T3 becomes lower than the output voltage of the second inverter transformer T4.Like this, when producing voltage difference between the output of first and second inverter transformers, the lamp current of main circuit side and produce difference between current from the lamp current of circuit side.At this moment, consistent for the lamp current that makes the main circuit side in the shunt transformer with lamp current from circuit side, produce voltage, obtain current balance type.
Like this, owing on three grades of coils of shunt transformer, produce voltage high when ratio is common to move, therefore can detect this voltage by comparator 31.When comparator 31 detected the change of voltage, to control circuit 32 output detection signals, control circuit 32 these detection signals of response stopped the switch of the switching circuit that is comprised in first and second inverters.The output of comparator 31 is latched, until power supply is connected once more.In addition, just under the situation that inverter transformer T3 or T4 have problems, even under the situation that any one lamp of for example lamp Lp31～Lp3n has problems, the electric current that flows through the shunt transformer also produces change, therefore can in comparator 31, detect.
In the example of Figure 12, three grades of coils are set on each shunt transformer carry out the detection of electric current, but also can detect with other method.Because shunt transformer in the main circuit and the shunt transformer from circuit are joined together, therefore can make the action of the electric current homogenizing that in all shunt transformers, flows through.Therefore, when producing imbalance in any one shunt transformer, its influence can feed through to other shunt transformer.Therefore, if the circuit of the variation that detects electric current is set, then just can detect the generation of problem on any shunt transformer at least.
Like this, according to the 8th execution mode, owing to detect the unusual of bright circuit for lamp, and the action of bright circuit for lamp is stopped, so can improve fail safe.In addition, do not stop the action of bright circuit for lamp sometimes yet and improve fail safe by the restriction output current.For inverter transformer, also constitute with one sometimes.
(the 9th execution mode)
Figure 13 represents the circuit example of the lamp-enlightened device that the 9th execution mode relates to.The lamp-enlightened device that the 9th execution mode relates to is the distortion of the lamp-enlightened device that relates to of the 8th execution mode, use transformer TB21a～TB2na to replace shunt transformer TB21～TB22, use transformer TB31a～TB3na to replace shunt transformer TB31～TB3n.Transformer TB21a～TB2na and transformer TB31a～TB3na produce the voltage with the voltage same polarity of primary coil secondarily on level coil and the three grades of coils.
The first terminal of the primary coil of transformer TB21a is connected on the first terminal of transformer T3, and second terminal of the primary coil of transformer TB21a is connected on the first terminal of lamp Lp31.The first terminal of the primary coil of transformer TB22a is connected on the first terminal of transformer T3, and second terminal of the primary coil of transformer TB22a is connected on the first terminal of lamp Lp32.The first terminal of the primary coil of transformer TB2na is connected on the first terminal of transformer T3, and second terminal of the primary coil of transformer TB2na is connected on the first terminal of lamp Lp3n.The first terminal of the primary coil of transformer TB31a is connected on the first terminal of transformer T4, and second terminal of the primary coil of transformer TB31a is connected on second terminal of lamp Lp31.The first terminal of the primary coil of transformer TB32a is connected on the first terminal of transformer T4, and second terminal of the primary coil of transformer TB32a is connected on second terminal of lamp Lp32.The first terminal of the primary coil of transformer TB3na is connected on the first terminal of transformer T4, and second terminal of the primary coil of transformer TB3na is connected on second terminal of lamp Lp3n.
The first terminal of the secondary coil of transformer TB21a is connected on the first terminal of transformer TB31a.These terminals are terminals of same polarity.On the other hand, second terminal of the secondary coil of transformer TB21a is connected on the first terminal of secondary coil of transformer TB22a.Second terminal of the secondary coil of transformer TB22a is connected on the first terminal of secondary coil of not shown transformer TB23a.Second terminal of the secondary coil of transformer TB2 (n-1) a is connected on the first terminal of secondary coil of transformer TB2na.Like this, the secondary coil of the transformer TB21a～TB2na of epimere, the terminal of the polarity that it differs from one another couples together.
In addition, second terminal of the secondary coil of transformer TB2na is connected on second terminal of secondary coil of transformer TB3na.These terminals are terminals of same polarity.On the other hand, the first terminal of the secondary coil of transformer TB3na is connected on second terminal of secondary coil of not shown transformer TB3 (n-1) a.The first terminal of the secondary coil of transformer TB33a is connected on second terminal of secondary coil of transformer TB32a.The first terminal of the secondary coil of transformer TB32a is connected on second terminal of secondary coil of transformer TB31a.Like this, the secondary coil of the transformer TB31a～TB3na of hypomere, the terminal of the polarity that it differs from one another couples together.
Illustrated in the 8th execution mode that for differential driving lamp Lp31～Lp3n, the transformer TB21a～TB2na of epimere and the transformer TB31a～TB3na of hypomere were driven with different polarity.Therefore, though the terminal of the same polarity of the secondary coil of the secondary coil of transformer TB21a and transformer TB31a link together,, because differential driving lamp Lp31, therefore be that actual polarity is that the terminal of opposed polarity is connected to each other together.Equally,, the terminal of the secondary coil of transformer TB2na and the same polarity of the secondary coil of transformer TB3na is in the same place though being connected to each other, because differential driving lamp Lp3n, therefore actual polarity is that the different terminal of polarity is connected to each other together.That is, the secondary coil of the secondary coil of transformer TB21a～TB2na and transformer TB31a～TB3na has constituted closed loop, and its terminal that has produced the polarity that differs from one another is joined together.
In the 9th execution mode, differential like this driving lamp Lp31～Lp3n makes the electric current homogenizing that flows through each lamp, thereby makes the brightness uniformity of lamp Lp31～Lp3n.
The structure of part in addition is identical with the 8th execution mode with action.
Embodiments of the present invention more than have been described, but the present invention is not limited to this, for example also can above-mentioned execution mode be made up arbitrarily.In addition, as long as defer to above-mentioned aim, also can partly be replaced into other circuit sometimes with identical function.
Claims (3)
1. lamp-enlightened device comprises:
One or more inverter transformers;
First balancer, it comprises first transformer, the primary coil of this first transformer is connected on the end of lamp specific among the secondary coil of above-mentioned one or more inverter transformers and a plurality of lamp, is used to make the electric current homogenizing that flows into these a plurality of lamps;
Second balancer, it comprises second transformer, the primary coil of this second transformer is connected on the other end of lamp specific among the secondary coil of above-mentioned one or more inverter transformers and the above-mentioned a plurality of lamp, is used to make the electric current homogenizing that flows into above-mentioned a plurality of lamps; And
Provide the device of mutually anti-phase voltage to the two ends of above-mentioned a plurality of lamps,
Position with secondary coil of the secondary coil of above-mentioned first transformer that is connected in series and above-mentioned second transformer.
2. lamp-enlightened device according to claim 1 is characterized in that:
Have a plurality of above-mentioned first transformers and above-mentioned second transformer,
Above-mentioned first transformer each other, secondary coil is connected in series by the different relation of polarity,
Above-mentioned second transformer each other, secondary coil is connected in series by the different relation of polarity,
The secondary coil of the secondary coil of at least 1 above-mentioned first transformer and at least 1 above-mentioned second transformer is connected in series by the identical relation of polarity.
3. lamp-enlightened device according to claim 1 is characterized in that:
Above-mentioned first balancer has a plurality of first transformers,
The secondary coil of the primary coil of each above-mentioned first transformer and 1 load lamp and above-mentioned one or more inverter transformers is connected in series,
The secondary coil of this first transformer is connected on the terminal of opposed polarity of secondary coil of other any one above-mentioned first transformer in above-mentioned first balancer,
Above-mentioned second balancer has a plurality of second transformers,
The secondary coil of the primary coil of each above-mentioned second transformer and 1 load lamp and above-mentioned one or more inverter transformers is connected in series,
The secondary coil of this second transformer is connected on the terminal of opposed polarity of secondary coil of other any one above-mentioned second transformer in above-mentioned second balancer,
The secondary coil of the transformer in the secondary coil of the transformer in above-mentioned first balancer and above-mentioned second balancer connects into closed loop.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004322302 | 2004-11-05 | ||
| JP322302/2004 | 2004-11-05 | ||
| JP218201/2005 | 2005-07-28 |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2005101154845A Division CN1770946B (en) | 2004-11-05 | 2005-11-04 | lighting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101668374A true CN101668374A (en) | 2010-03-10 |
Family
ID=36751865
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910171146A Pending CN101668374A (en) | 2004-11-05 | 2005-11-04 | Lamp-lighting apparatus |
Country Status (2)
| Country | Link |
|---|---|
| JP (6) | JP2007019039A (en) |
| CN (1) | CN101668374A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106602865A (en) * | 2016-12-26 | 2017-04-26 | 中国电子科技集团公司第十研究所 | Energy storage capacitor charging circuit and pulse laser power supply |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI391029B (en) * | 2007-12-31 | 2013-03-21 | Ampower Technology Co Ltd | System for driving a plurality of discharge lamps |
| KR100867551B1 (en) | 2007-05-18 | 2008-11-10 | 삼성전기주식회사 | LED array driving device |
| USD581084S1 (en) | 2008-03-13 | 2008-11-18 | Stanley Electric Co., Ltd. | Foot light |
| JP4898745B2 (en) * | 2008-06-13 | 2012-03-21 | 東光株式会社 | Hot cathode discharge tube lighting circuit |
| WO2010004821A1 (en) * | 2008-07-11 | 2010-01-14 | シャープ株式会社 | Lighting device, display device, and television reception device |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07111916B2 (en) * | 1987-01-14 | 1995-11-29 | 松下電工株式会社 | Discharge lamp lighting device |
| JPS63237393A (en) * | 1987-03-26 | 1988-10-03 | 松下電工株式会社 | Discharge lamp lighter |
| JPH01167985A (en) * | 1987-12-23 | 1989-07-03 | Matsushita Electric Works Ltd | Lamp abnormality detecting circuit |
| JPH0634396B2 (en) * | 1987-12-23 | 1994-05-02 | 松下電工株式会社 | Lamp abnormality detection circuit |
| JPH03283297A (en) * | 1990-03-29 | 1991-12-13 | Toshiba Lighting & Technol Corp | discharge lamp lighting device |
| JPH04163892A (en) * | 1990-10-26 | 1992-06-09 | Matsushita Electric Works Ltd | Discharge lamp lighting device |
| JPH0686537A (en) * | 1992-08-31 | 1994-03-25 | Toshiba Lighting & Technol Corp | Power supply device, discharge lamp lighting device, and lighting device using the same |
| JPH06251890A (en) * | 1993-02-24 | 1994-09-09 | Toshiba Lighting & Technol Corp | Dimming device in discharge lamp lighting device |
| US5828156A (en) * | 1996-10-23 | 1998-10-27 | Branson Ultrasonics Corporation | Ultrasonic apparatus |
| JP2982804B2 (en) * | 1998-01-16 | 1999-11-29 | サンケン電気株式会社 | Discharge lamp lighting device |
| TWI256860B (en) * | 2001-06-29 | 2006-06-11 | Hon Hai Prec Ind Co Ltd | Multi-tube driving system |
| JP4658061B2 (en) * | 2003-10-06 | 2011-03-23 | マイクロセミ・コーポレーション | Current distribution method and apparatus for operating a plurality of CCF lamps |
-
2005
- 2005-11-04 CN CN200910171146A patent/CN101668374A/en active Pending
-
2006
- 2006-10-06 JP JP2006275603A patent/JP2007019039A/en active Pending
- 2006-10-06 JP JP2006275602A patent/JP3975224B2/en not_active Expired - Fee Related
- 2006-10-06 JP JP2006275604A patent/JP3938593B2/en not_active Expired - Fee Related
-
2007
- 2007-04-19 JP JP2007110830A patent/JP4551420B2/en not_active Expired - Fee Related
- 2007-07-04 JP JP2007175974A patent/JP2007287700A/en active Pending
-
2008
- 2008-06-30 JP JP2008170330A patent/JP2008235291A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106602865A (en) * | 2016-12-26 | 2017-04-26 | 中国电子科技集团公司第十研究所 | Energy storage capacitor charging circuit and pulse laser power supply |
| CN106602865B (en) * | 2016-12-26 | 2019-10-25 | 中国电子科技集团公司第十一研究所 | An energy storage capacitor charging circuit and pulse laser power supply |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2008235291A (en) | 2008-10-02 |
| JP3975224B2 (en) | 2007-09-12 |
| JP2007019040A (en) | 2007-01-25 |
| JP3938593B2 (en) | 2007-06-27 |
| JP2007005326A (en) | 2007-01-11 |
| JP2007188902A (en) | 2007-07-26 |
| JP2007019039A (en) | 2007-01-25 |
| JP4551420B2 (en) | 2010-09-29 |
| JP2007287700A (en) | 2007-11-01 |
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Application publication date: 20100310 |