CN200987230Y - Protection device and multi-lamp drive system using it - Google Patents
Protection device and multi-lamp drive system using it Download PDFInfo
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- CN200987230Y CN200987230Y CNU2006201478257U CN200620147825U CN200987230Y CN 200987230 Y CN200987230 Y CN 200987230Y CN U2006201478257 U CNU2006201478257 U CN U2006201478257U CN 200620147825 U CN200620147825 U CN 200620147825U CN 200987230 Y CN200987230 Y CN 200987230Y
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- impedance component
- protective device
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
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Abstract
A protection device is used for a multi-lamp tube driving system. The multi-lamp driving system comprises a driving device and a current balancing device. The driving device drives a plurality of lamp tubes, and the current balancing device balances tube currents of the lamp tubes and is provided with a plurality of detection points. The protection device comprises at least one detection unit and a judgment unit. The at least one detection unit comprises a plurality of first impedance components and a second impedance component, wherein the first end of each first impedance component is coupled with the corresponding detection point, and the second impedance component is coupled with the second end of each first impedance component. The voltage across the first and second ends of the second impedance element is related to the sum of the voltage levels of the detecting points coupled to the first impedance elements. The judging unit is coupled with the second impedance component of the at least one detecting unit, so that when judging that at least one of the lamp tubes is abnormally driven according to the cross voltage between the first end and the second end of the second impedance component, a protection signal is output to close the driving device, and the abnormal protection function is achieved.
Description
Technical field
The relevant a kind of protective device of the utility model and use its multi-lamp-tube driving system, and particularly relevant a kind of highly sensitive and protective device that cost is low and use its multi-lamp-tube driving system.
Background technology
For current balancing device as employed multi-lamp-tube driving system in present large-sized display and balance lamp current thereof; whether unusually existing some in recent years patents disclose the protective circuit of can arranging in pairs or groups and detect fluorescent tube driving; to reduce the situation that assembly is damaged, reach preferable defencive function.
Please refer to Fig. 1, it is the schematic diagram of a traditional multi-lamp-tube driving system.Multi-lamp-tube driving system 100 uses a kind of ring type current balancing device (Ring Balancer) 110 that is disclosed in No. the 1st, 671,521, the European patents, and design has the protective circuit 120 when at fluorescent tube unusual (open circuit, short circuit or overload) taking place.Yet; because current balancing device 110 is arranged at the high-pressure side of fluorescent tube L1～Lk; when unusual the driving takes place in fluorescent tube; deliver to the signal sensitivity deficiency of test point voltage V1～Vk via stray capacitance C11～Cn2, cause protective circuit 120 misoperations easily and correctly output protection signal S come control Driver Circuit or powered-down.
In addition; as European patent the 1st, 581, suspension joint type (Floating type) current balancing device that is disclosed in No. 030; or the Zaulas formula current balancing device that is disclosed in Japan Patent 2004-335443 number, the protective circuit of being arranged in pairs or groups has equally all been used the detection diode.But when light tube group wherein a fluorescent tube take place when unusual, balancing transformer corresponding in the current balancing device will produce very high voltage, detect this moment diode because of must adopt energy high pressure resistant cause higher cost.In addition, when display sizes is big more, when needing the bigger area source of scope, also be that required fluorescent tube number is many more, the quantity that detects diode also needs corresponding increasing, and this will cause bigger burden to cost.
Therefore, the detection sensitivity when how to reduce the protective circuit cost and improving for abnormal condition of lamp tube, real is that present industry is desired the positive problem that solves.
The utility model content
In view of this, the purpose of this utility model just provides a kind of protective device and uses its multi-lamp-tube driving system.Protective device uses general impedance component to replace high-voltage diode, even and current balancing device be arranged at the high-pressure side of fluorescent tube, the detection sensitivity of protective device during for abnormal condition of lamp tube is also still more existing significantly to be improved.Whereby, protective device of the present utility model can effectively reduce manufacturing cost, and makes the multi-lamp-tube driving system of using it obtain better protection effect.
According to the purpose of this utility model, a kind of protective device is proposed, be used for multi-lamp-tube driving system.Multi-lamp-tube driving system comprises drive unit and current balancing device.Drive unit is in order to driving a plurality of fluorescent tubes, and current balancing device is in order to the tube current of these fluorescent tubes of balance, and has a plurality of test points.Protective device comprises at least one detecting unit and judging unit.This at least one detecting unit comprises a plurality of first impedance components and one second impedance component, and first end of each first impedance component couples corresponding test point, and second impedance component couples second end of each first impedance component.First end of second impedance component and the cross-pressure between second end are relevant to the summation of the voltage quasi position of these test points that these first impedance components are coupled.Judging unit couples second impedance component of this at least one detecting unit; and in order to when judging these fluorescent tubes at least one abnormal condition of lamp tube wherein according to first end of second impedance component and the cross-pressure between second end and drive, the output protection signal is closed drive unit.
According to the purpose of this utility model, a kind of multi-lamp-tube driving system is proposed.Multi-lamp-tube driving system comprises drive unit, current balancing device and protective device.Drive unit is in order to driving a plurality of fluorescent tubes, and current balancing device is in order to the tube current of these fluorescent tubes of balance, and has a plurality of test points.Protective device comprises at least one detecting unit and judging unit.This at least one detecting unit comprises a plurality of first impedance components and one second impedance component, and first end of each first impedance component couples corresponding test point, and second impedance component couples second end of each first impedance component.First end of second impedance component and the cross-pressure between second end are relevant to the summation of the voltage quasi position of these test points that these first impedance components are coupled.Judging unit couples second impedance component of this at least one detecting unit; and in order to when judging these fluorescent tubes at least one abnormal condition of lamp tube wherein according to first end of second impedance component and the cross-pressure between second end and drive, the output protection signal is closed drive unit.
Protective device of the present utility model and use its multi-lamp-tube driving system; protective device uses general impedance component to replace high-voltage diode; even and current balancing device is arranged at the high-pressure side of fluorescent tube, the detection sensitivity of protective device during for abnormal condition of lamp tube is also still more existing significantly to be improved.Whereby, protective device of the present utility model can effectively reduce manufacturing cost, and makes the multi-lamp-tube driving system of using it obtain better protection effect.
For above-mentioned purpose of the present utility model, feature and advantage can be become apparent, below especially exemplified by preferred embodiment, and conjunction with figs. is elaborated.
Description of drawings
Fig. 1 is the schematic diagram of a traditional multi-lamp-tube driving system.
Fig. 2 is the calcspar according to the multi-lamp-tube driving system of the utility model first embodiment.
Fig. 3 A is first kind of circuit diagram of the multi-lamp-tube driving system of Fig. 2.
Fig. 3 B is second kind of circuit diagram of the multi-lamp-tube driving system of Fig. 2.
Fig. 3 C is the third circuit diagram of the multi-lamp-tube driving system of Fig. 2.
Fig. 3 D is the 4th a kind of circuit diagram of the multi-lamp-tube driving system of Fig. 2.
Fig. 4 is the circuit diagram according to the multi-lamp-tube driving system of the utility model second embodiment.
Fig. 5 is the circuit diagram according to the multi-lamp-tube driving system of the utility model the 3rd embodiment.
Embodiment
First embodiment
Please refer to Fig. 2, it is the calcspar according to the multi-lamp-tube driving system of the utility model first embodiment.Multi-lamp-tube driving system 200 comprises drive unit 210, current balancing device 220, protective device 230 and feedback device 240.Drive unit 210 for example comprises PWM control IC, full-bridge module and high-tension transformer etc., and in order to drive a plurality of fluorescent tube L1～Ln, n is a positive integer.Fluorescent tube L1～Ln for example be cathode fluorescent tube (Cold Cathode Fluorescent Lamp, CCFL).Current balancing device 220 has a plurality of test point d1～dk, and k is a positive integer, is that example explains in first embodiment and with the high-pressure side that is arranged at fluorescent tube L1～Ln.
Please refer to Fig. 3 A, it is first kind of circuit diagram of the multi-lamp-tube driving system of Fig. 2.In Fig. 3 A, current balancing device 220 is to be example with ring type current balancing device (Ring Balancer), and comprises a plurality of balancing transformers 221 (1)～221 (n).At this moment, one end of the primary side of balancing transformer 221 (1)～221 (n) (coupling the output of drive unit 210) is respectively as test point d1～dk, the other end of the primary side of balancing transformer 221 (1)～221 (n) has contact altogether, promptly as reference point d.The first impedance component z1～zk and the second impedance component z can optionally adopt Inductive component, capacitance component or resistor assembly respectively.Be to be all capacitance component and to have identical resistance value in Fig. 3 A, and the second impedance component z is that resistor assembly is an example with first impedance component z1～zk.
In addition, judging unit 232 comprise cut wave circuit 232 (1) (clipper), buffer circuit 232 (2), peak detection circuit 232 (3) (peak detector) and comparison circuit 232 (4) (comparator).The high-pressure side of buffer circuit 232 (2) is first end and second end that couples the second impedance component z via section wave circuit 232 (1), and two inputs of comparison circuit 232 (4) couple a reference voltage Vref respectively and couple the low-pressure side of buffer circuit 232 (2) via peak detection circuit 232 (3).
When fluorescent tube L1～Ln driven, the voltage quasi position of test point d1～dn generally is about 10V, but when an abnormal condition of lamp tube wherein, but voltage quasi position moment of corresponding test point reaches about 1000V.And to this, change compared to the existing protective circuit as Fig. 1 with the cross-pressure of time second impedance component z, sensitivity can reach more than nearly a hundred times.At this moment, the buffer circuit 232 (2) of judging unit 230 is converted to low-pressure side output with on high-tension side input signal, handles for subordinate's low-voltage circuit, avoids subordinate's circuit to disturb higher level's circuit simultaneously.In Fig. 3 A～3D, buffer circuit 232 (2) uses optical couplers (photocoupler), but in other execution mode, also can adopt as isolating transformer etc.Export the voltage waveform of corresponding abnormal condition of lamp tube from low-pressure side when buffer circuit 232 (2); and reach an input of comparison circuit 232 (4) via peak detection circuit 232 (3); and when accurate position surpassed the reference voltage Vref of another input, comparison circuit 232 (4) just output protection signal S cut out drive unit 210.
As shown in Figure 3A, cut wave circuit 232 (1) and improve the cross-pressure proportional difference of the second impedance component z between fluorescent tube normally reaches unusually with Zener diode (zener diode), peak detection circuit 232 (3) is then to export the maximum reference position value of the voltage waveform that is received by the mode of diode pair electric capacity charging.Both are mainly used to further increase the sensitivity of protective device 230, but inner separately circuit unit design is not limited to diagram.In addition, also configurable as cutting wave circuit 232 (1) in the low-pressure side of buffer circuit 232 (2).
Please refer to Fig. 3 B, it is second kind of circuit enforcement figure of the multi-lamp-tube driving system of Fig. 2.Fig. 3 B and Fig. 3 A difference be, the primary side of the balancing transformer 222 (1)～222 (n) of current balancing device 220 be connected in series in twos (such as in Taiwan patent case M291174 number announcement); And an end of the secondary side of each balancing transformer 222 (1)～222 (n) is respectively as test point d1～dk (same k=n), and the common contact of the other end of the secondary side of balancing transformer 222 (1)～222 (n) can be as with reference to some d.
Please refer to Fig. 3 C, it is the third circuit diagram of the multi-lamp-tube driving system of Fig. 2.Fig. 3 C and Fig. 3 B difference are that buffer circuit 232 (2) is to use isolating transformer, and a section wave circuit 232 (1) is coupled between peak detection circuit 232 (3) and the comparison circuit 232 (4).
Please refer to Fig. 3 D, it is the 4th a kind of circuit diagram of the multi-lamp-tube driving system of Fig. 2.Fig. 3 D and Fig. 3 C difference be, current balancing device 220 is to be example with Zaulas formula current balancing device, and comprises several balancing transformers 224 (1)～224 (7).In addition, connect end altogether as test point di, i=1～4 and with the primary side of balancing transformer 224 (i) and secondary side; And the end (coupling the output of drive unit 210) that connects altogether of the primary side of balancing transformer 224 (7) and secondary side is as reference point d.At this moment, the first impedance component quantity of detecting unit 231 is not equal to fluorescent tube quantity.
Second embodiment
Please refer to Fig. 4, it is the circuit diagram according to the multi-lamp-tube driving system of the utility model second embodiment.Multi-lamp-tube driving system 400 and Fig. 3 B difference of Fig. 4 are; protective device 430 has two groups of detecting unit 431a and 431b; judging unit 432 also correspondence has two groups and cuts wave circuit 432 (1) a and 432 (1) b, two groups of buffer circuit 432 (2) a and 432 (2) b and two groups of peak detection circuit 432 (3) a and 432 (3) b, but is coupled to the same input of comparison circuit 432 (4) at last.In addition, test point d1～dk (k=n) also divides into two parts d1～dm and d (m+1)～dk, and m is for satisfying the positive integer of 2＜m＜k.As shown in Figure 4, detecting unit 431a and 431b couple test point d1～dm and d (m+1)～dk respectively.At this moment, if there is arbitrary fluorescent tube to take place when unusual among fluorescent tube L1～Lm, judging unit 432 can be protected action as changing according to the cross-pressure of the second impedance component za among the detecting unit 431a as first embodiment.For fluorescent tube L (m+1)～Ln take place when unusual situation also with.
When this kind execution mode mainly adapted to the increase of fluorescent tube number, the sensitivity meeting that the cross-pressure of second impedance component changes descended, and therefore set up another group detecting unit and shared test point partly.Certainly, test point d1 ~ dk also can divide into more parts, and the corresponding many groups detecting unit of collocation, to keep or to increase the overall sensitivity of protective device.
The 3rd embodiment
Please refer to Fig. 5, it is the circuit diagram according to the multi-lamp-tube driving system of the utility model the 3rd embodiment.Be that with multi-lamp-tube driving system 200 differences of above-mentioned Fig. 3 D the current balancing device 520 of multi-lamp-tube driving system 500 does not utilize reference point.At this moment, first end of first impedance component z1～z4 of detecting unit 531 couples test point d1～d4 respectively, and the first impedance component z5 and z6 couple test point d5 and d6 respectively.Second end of first impedance component z1～z4 couples first end of the second impedance component z in addition, and second end of the first impedance component z5 and z6 couples second end of the second impedance component z.
Have in the technical field under right the utility model and know that usually the knowledgeable can understand that also technology of the present utility model is not limited to the foregoing description.At first, (as European patent the 1st, 581, the suspension joint type current balancing device that is disclosed in No. 030) can use protective device of the present utility model equally when current balancing device was arranged at the low-pressure end of fluorescent tube.In addition, though the current balancing device of first embodiment has reference point, still can couple each first impedance component and second impedance component as the mode of embodiment.Moreover when the fluorescent tube number increased, the protective device of three embodiment also can be imitated the mode of second embodiment, couples test point respectively with detecting unit, to keep or to increase sensitivity.Certainly, the quantity of test point and position, the actual coupling mode of all visual its balance shunt assembly of which kind of current balancing device of employing is chosen, and whether defines reference point.Wherein, when desire is used to the impedance component of condensance, also can utilize the Copper Foil on the general circuit plate to form required condensance, further save manufacturing cost.
Protective device that the utility model the foregoing description is disclosed and the multi-lamp-tube driving system of using it; protective device uses general impedance component to replace high-voltage diode; even and current balancing device is arranged at the high-pressure side of fluorescent tube, the detection sensitivity of protective device during for abnormal condition of lamp tube is also still more existing significantly to be improved.Whereby, protective device of the present utility model can effectively reduce manufacturing cost, and makes the multi-lamp-tube driving system of using it obtain better protection effect.
In sum, though the utility model with the preferred embodiment announcement as above, yet it is not in order to limit the utility model.Have in the technical field under any and know the knowledgeable usually, in not breaking away from spirit and scope of the present utility model, when making various changes that are equal to and retouching.Therefore, protection range of the present utility model is when looking accompanying being as the criterion that the application's claim scope defined.
Claims (26)
1. protective device; be used for a multi-lamp-tube driving system; this multi-lamp-tube driving system comprises a drive unit and a current balancing device; this drive unit drives a plurality of fluorescent tubes; the tube current of these these fluorescent tubes of current balancing device balance; and have a plurality of test points, it is characterized in that this protective device comprises:
At least one detecting unit comprises:
A plurality of first impedance components, respectively one first end of this first impedance component couples this corresponding test point; And
One second impedance component couples respectively one second end of this first impedance component, and one first end of this second impedance component and the cross-pressure between one second end are relevant to the summation of the voltage quasi position of these test points that these first impedance components are coupled; And
One judging unit; couple this second impedance component of this at least one detecting unit; and, export a guard signal and close this drive unit in order to when judging wherein at least one abnormal condition of lamp tube driving of these fluorescent tubes according to this first end of this second impedance component of this at least one detecting unit and the cross-pressure between this second end.
2. protective device as claimed in claim 1 is characterized in that this current balancing device comprises a plurality of balancing transformers, and respectively an end of the primary side of this balancing transformer or secondary side is this test point.
3. protective device as claimed in claim 2; the primary side or the secondary side that it is characterized in that these balancing transformers have contact altogether; these second ends of these first impedance components couple this first end of this second impedance component, and this second end of this second impedance component couples this common contact.
4. protective device as claimed in claim 2; one of it is characterized in that in these balancing transformers having a receiving terminal; this receiving terminal couples a drive signal of this drive unit; these second ends of these first impedance components couple this first end of this second impedance component, and this second end of this second impedance component couples this receiving terminal.
5. protective device as claimed in claim 2; it is characterized in that these second ends of these first impedance components of part couple this first end of this second impedance component, these second ends of these of another part first impedance component couple this second end of this second impedance component.
6. protective device as claimed in claim 1 is characterized in that respectively this first impedance component is an Inductive component, a capacitance component or a resistor assembly.
7. protective device as claimed in claim 1 is characterized in that the resistance value of these first impedance components is identical.
8. protective device as claimed in claim 1 is characterized in that this second impedance component is an Inductive component, a capacitance component or a resistor assembly.
9. protective device as claimed in claim 1 is characterized in that this judging unit comprises a buffer circuit, and the high-pressure side of this buffer circuit couples this first end and this second end of this second impedance component.
10. protective device as claimed in claim 9 is characterized in that this buffer circuit is an optical coupler or an isolating transformer.
11. protective device as claimed in claim 9; it is characterized in that this judging unit also comprises a comparison circuit; two inputs of this comparison circuit couple the low-pressure side and a reference voltage of this buffer circuit respectively, and in order to export this guard signal during greater than this reference voltage when the accurate position of the low-pressure side of this buffer circuit.
12. protective device as claimed in claim 11 is characterized in that this judging unit also comprises a peak detection circuit, is coupled between the low-pressure side and this comparison circuit of this buffer circuit.
13. protective device as claimed in claim 11 is characterized in that this judging unit also comprises one section wave circuit, is coupled between the high-pressure side of this buffer circuit and this second impedance component or between the low-pressure side and this comparison circuit of this buffer circuit.
14. a multi-lamp-tube driving system comprises:
One drive unit is in order to drive a plurality of fluorescent tubes;
One current balancing device, in order to the tube current of these fluorescent tubes of balance, this current balancing device also has a plurality of test points; And
One protective device comprises:
At least one detecting unit comprises:
A plurality of first impedance components, respectively one first end of this first impedance component couples this corresponding test point; And
One second impedance component couples respectively one second end of this first impedance component, and one first end of this second impedance component and the cross-pressure between one second end are relevant to the summation of the voltage quasi position of these test points that these first impedance components are coupled; And
One judging unit; couple this second impedance component of this at least one detecting unit; and, export a guard signal and close this drive unit in order to when judging wherein at least one abnormal condition of lamp tube driving of these fluorescent tubes according to this first end of this second impedance component of this at least one detecting unit and the cross-pressure between this second end.
15. protective device as claimed in claim 14 is characterized in that this current balancing device comprises a plurality of balancing transformers, respectively an end of the primary side of this balancing transformer or secondary side is this test point.
16. protective device as claimed in claim 15; the primary side or the secondary side that it is characterized in that these balancing transformers have contact altogether; these second ends of these first impedance components couple this first end of this second impedance component, and this second end of this second impedance component couples this common contact.
17. protective device as claimed in claim 15; it is characterized in that one of these balancing transformers have a receiving terminal; this receiving terminal couples a drive signal of this drive unit; these second ends of these first impedance components couple this first end of this second impedance component, and this second end of this second impedance component couples this receiving terminal.
18. protective device as claimed in claim 15; it is characterized in that these second ends of these first impedance components of part couple this first end of this second impedance component, these second ends of these of another part first impedance component couple this second end of this second impedance component.
19. protective device as claimed in claim 14 is characterized in that respectively this first impedance component is an Inductive component, a capacitance component or a resistor assembly.
20. protective device as claimed in claim 14 is characterized in that the resistance value of these first impedance components is identical.
21. protective device as claimed in claim 14 is characterized in that this second impedance component is an Inductive component, a capacitance component or a resistor assembly.
22. protective device as claimed in claim 14 is characterized in that this judging unit comprises a buffer circuit, the high-pressure side of this buffer circuit couples this first end and this second end of this second impedance component.
23. protective device as claimed in claim 22 is characterized in that this buffer circuit is an optical coupler or an isolating transformer.
24. protective device as claimed in claim 22; it is characterized in that this judging unit also comprises a comparison circuit; two inputs of this comparison circuit couple the low-pressure side and a reference voltage of this buffer circuit respectively, and in order to export this guard signal during greater than this reference voltage when the accurate position of the low-pressure side of this buffer circuit.
25. protective device as claimed in claim 24 is characterized in that this judging unit also comprises a peak detection circuit, is coupled between the low-pressure side and this comparison circuit of this buffer circuit.
26. protective device as claimed in claim 24 is characterized in that this judging unit also comprises one section wave circuit, is coupled between the high-pressure side of this buffer circuit and this second impedance component or between the low-pressure side and this comparison circuit of this buffer circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2006201478257U CN200987230Y (en) | 2006-11-06 | 2006-11-06 | Protection device and multi-lamp drive system using it |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2006201478257U CN200987230Y (en) | 2006-11-06 | 2006-11-06 | Protection device and multi-lamp drive system using it |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN200987230Y true CN200987230Y (en) | 2007-12-05 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2006201478257U Expired - Fee Related CN200987230Y (en) | 2006-11-06 | 2006-11-06 | Protection device and multi-lamp drive system using it |
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| Country | Link |
|---|---|
| CN (1) | CN200987230Y (en) |
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2006
- 2006-11-06 CN CNU2006201478257U patent/CN200987230Y/en not_active Expired - Fee Related
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| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20071205 Termination date: 20131106 |