JP2007280916A - Lamp lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce cost while suppressing degradation of current balance. <P>SOLUTION: This lamp lighting device for driving a plurality of lamps in parallel includes a plurality of balancer transformers connected to the plurality of lamps including a first lamp and a second lamp for regulating a current amount among the lamps. Each balancer transformer includes a primary winding and a secondary winding. One-side ends of the first lamp and the second lamp are respectively connected to the primary windings of the balancer transformers different from each other; the other-side ends of the first lamp and the second lamp are respectively connected to the primary winding of a common balancer transformer; and the secondary windings of at least two of the balancer transformers are connected in series to each other. Since the other-side ends of the first lamp and the second lamp are connected to the primary winding of the common balancer transformer like that, the number of balancer transformers can be reduced as compared with separately connecting the balancer transformers. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lamp lighting device.

  US Patent Application Publication No. 2005-93471A1 and US Application Publication No. 2005-93472A1 disclose a lamp lighting device as shown in FIG. That is, for example, the primary windings of the balancer transformers T201 to T212 are connected to both ends of the lamps L101 to L106 which are cold cathode ray tubes, and the other main ends of the primary windings of the balancer transformers T201 to T206 are connected to the first main The other end of the primary winding of the balancer transformers T207 to T212 is connected to the secondary winding side of the second main transformer T102. The AC power supply V101 is connected to the primary winding side of the first main transformer T101, and the AC power supply V102 is connected to the primary winding side of the second main transformer T102. Here, the secondary windings of the balancer transformers T201 to T206 are connected to form the closed loop 101, and the secondary windings of the balancer transformers T207 to T212 are also connected to form the closed loop 102. ing.

  Each of the AC power supply V101 and the AC power supply V102 has the first and second main transformers at both ends of the lamps L101 to L106, with a voltage half the voltage required for lighting the lamps L101 to L106 in reverse phase. By applying the voltage via T101 and T102, the lamps L101 to L106 are turned on. By driving in this way, even a lamp that requires a high voltage, such as a large-sized liquid crystal television, can be lit at a voltage of 1/2 if only one side of the lamp is viewed. The required withstand voltage can be halved. Also, by making the currents of the secondary windings of the balancer transformers T201 to T206 the same by the closed loop 101, the currents flowing through the lamps L101 to L106 connected to the primary winding side are made uniform, and the luminance between the lamps is adjusted. Variations are suppressed. Similarly, by making the currents of the secondary windings of the balancer transformers T207 to T212 the same by the closed loop 102, the currents flowing in the lamps L101 to L106 connected to the primary winding side are made uniform, and the brightness between the lamps. It is designed to suppress the variation of.

In addition to the lamp lighting device described above, the above publication discloses a method of providing a closed loop on only one side of the lamp and a lamp lighting device that drives both ends of the lamp using one AC power source.
US Application Publication No. 2005-93471A1 US Application Publication No. 2005-93472 A1

  The lamp lighting device as shown in FIG. 8 has a very good current balance between the lamps, but requires two balancer transformers for each lamp, which is problematic in terms of cost. On the other hand, if balancers and transformers are easily reduced, the current balance is lost and variations in luminance occur.

  Accordingly, an object of the present invention is to provide a lamp lighting device that enables cost reduction while suppressing deterioration of current balance.

  The lamp lighting device according to the first aspect of the present invention that drives a plurality of lamps in parallel is connected to a plurality of lamps including a first lamp and a second lamp, and a plurality of lamps adjust the amount of current between the lamps. And an AC power source connected to at least one terminal of the plurality of lamps via the balancer transformer. The balancer transformer has a primary winding and a secondary winding. The first terminals of the first lamp and the second lamp are respectively connected to the primary windings of different balancer transformers, and the second terminals of the first lamp and the second lamp are common. The balancer transformer is connected to a primary winding, and at least two secondary windings of the balancer transformer are connected in series.

  In this way, since the second terminals of the first lamp and the second lamp are connected to the primary winding of the common balancer transformer, the number of balancer transformers can be reduced rather than connecting to the balancer transformer separately. Can be reduced. A balancer / transformer may be connected in common to three or more lamps.

  The AC power source is connected to the other end of the primary winding of the balancer transformer connected to the first terminals of the first lamp and the second lamp, and the first power source of the first lamp and the second lamp The other end of the primary winding of the balancer transformer connected to the second terminal may be grounded. On the other hand, the AC power source is connected to the other end of the primary winding of the balancer transformer connected to the second terminal of the first lamp and the second lamp, and the first power source of the first lamp and the second lamp The other end of the primary winding of the balancer transformer connected to one terminal may be grounded.

  The lamp lighting device according to the second aspect of the present invention includes a balancer transformer that is connected to the first lamp and the second lamp and adjusts the amount of current between the lamps, and the first and second lamps. And an AC power source connected to at least one of the terminals via a balancer transformer. The balancer transformer has a primary winding and a secondary winding. One end of the first lamp and the second lamp is connected to the primary winding of the common balancer transformer, and the other end of the first lamp and the second lamp is wired so that a current flows independently. There are a plurality of sets of the first lamp and the second lamp, and the secondary windings of the balancer transformer are connected so as to form a closed loop.

  For example, by connecting only one end of the lamp to the primary winding of a common balancer transformer, the current balance can be minimized.

  Furthermore, the lamp lighting device according to the third aspect of the present invention that drives the plurality of lamps in parallel and differentially is connected to the plurality of lamps including the first lamp and the second lamp, and the current between the lamps. The balancer transformer having a plurality of balancer transformers for adjusting the quantity has a primary winding and a secondary winding. The first terminals of the first lamp and the second lamp are respectively connected to the first terminals of the primary windings of different balancer transformers, and the second terminals of the first lamp and the second lamp are connected. The terminal is connected to the first terminal of the primary winding of the common balancer transformer. A current of the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the first terminals of the first lamp and the second lamp, and the first lamp and A current having a phase opposite to that of the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the second terminal of the second lamp. The secondary windings of at least two balancer transformers are connected in series. Thus, it is possible to cope with the case where the lamp is differentially driven.

  According to a fourth aspect of the present invention, a lamp lighting device for driving a plurality of lamps in parallel and differentially is connected to a plurality of lamps including the first to fourth lamps, and the amount of current between the lamps is determined. A plurality of balancer transformers to be adjusted and an AC power source connected to both terminals of the plurality of lamps via the balancer transformer. The balancer transformer has a primary winding and a secondary winding. The first terminals of the first lamp and the second lamp are respectively connected to the primary windings of different balancer transformers, and the second terminals of the first lamp and the second lamp are common. Connected to the primary winding of the balancer transformer. The first terminals of the third lamp and the fourth lamp are respectively connected to primary windings of different balancer transformers, and the second terminals of the third lamp and the fourth lamp are common. Connected to the primary winding of the balancer transformer. The secondary windings of at least two balancer transformers are connected in series. Furthermore, the first terminals of the first lamp and the second lamp are arranged so as to face the same direction, and the second terminals of the third lamp and the fourth lamp face each other. The first terminals of the first lamp and the second lamp and the first terminals of the third lamp and the fourth lamp are arranged in the opposite directions.

  In this way, when the primary winding of a common balancer transformer is connected to the first terminals of two or more lamps, if the common balancer transformer is arranged in a cluster, luminance variations are likely to occur. For example, it is possible to suppress luminance variations as a whole by arranging them alternately. It is still more preferable if it can be dispersedly arranged.

  In the first, third and fourth embodiments of the present invention, among the plurality of lamps arranged in parallel, both terminals of two lamps arranged at both ends are provided with different balancers and The primary winding of the transformer may be connected. Since the lamps arranged at both ends are more susceptible to temperature changes and parasitic capacitances, the luminance variation as a whole becomes inconspicuous with this configuration.

  According to a fifth aspect of the present invention, a lamp lighting device for driving a plurality of lamps in parallel and differentially is connected to a plurality of lamps including a first lamp and a second lamp, and a current amount between the lamps is determined. Has multiple balancer transformers to adjust. The balancer transformer has a primary winding and a secondary winding, and the first terminals of the first lamp and the second lamp are respectively connected to the first terminals of the primary windings of different balancer transformers. The second terminal of the first lamp and the second lamp are connected to the first terminal of the primary winding of the common balancer transformer. A current of the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the first terminal of the first lamp and the second lamp, and the first lamp and A current having a phase opposite to that of the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the second terminal of the second lamp. The secondary windings of the balancer transformer are connected in a closed loop. In this way, it is possible to reduce the number of balancer transformers on one side and perform luminance balance after performing differential driving.

  Further, a current detection resistor may be included in the closed loop. In that case, you may make it further have a control circuit which controls the alternating current power supply connected to a lamp lighting device based on the signal from resistance for current detection.

  There are a plurality of circuits for realizing the above configuration, and specific examples are shown below, but the present invention is not limited to these.

  According to the present invention, it is possible to specify a lamp lighting device that can reduce costs while suppressing deterioration in current balance.

[Embodiment 1]
A lamp lighting device according to a first embodiment of the present invention is shown in FIG. The lamp lighting device according to the present embodiment includes AC power supplies V1 and V2, lamps L1 to L6 that are, for example, cold cathode ray tubes, main transformers T1 and T2, and a first balancer connected to two lamps. Transformers T3 to T5 and second balancer transformers T6 to T11 connected to one lamp are included.

  The AC power supply V1 is connected to the primary winding of the main transformer T1. One end of the secondary winding of the main transformer T1 is grounded, and the other end is one end of the primary winding of the first balancer transformer T3, one end of the primary winding of the first balancer transformer T4, One balancer transformer T5 is connected to one end of the primary winding. The other end of the primary winding of the first balancer transformer T3 is connected to one ends of the lamps L1 and L2. The other end of the primary winding of the first balancer transformer T4 is connected to one ends of the lamps L3 and L4. Further, the other end of the primary winding of the first balancer transformer T5 is connected to one ends of the lamps L5 and L6.

  The AC power supply V2 is connected to the primary winding of the main transformer T2, and outputs a voltage in phase with the AC power supply V1. However, since the polarity of the main transformer T2 is different from that of the main transformer T1, a reverse-phase voltage is output to the secondary winding side of the main transformer T2. One end of the secondary winding of the main transformer T2 is grounded, and the other end is connected to one end of the primary winding of the second balancer transformers T6 to T11. The other end of the primary winding of the second balancer transformer T6 is connected to the other end of the lamp L1. The other end of the primary winding of the second balancer transformer T7 is connected to the other end of the lamp L2. The other end of the primary winding of the second balancer transformer T8 is connected to the other end of the lamp L3. The other end of the primary winding of the second balancer transformer T9 is connected to the other end of the lamp L4. The other end of the primary winding of the second balancer transformer T10 is connected to the other end of the lamp L5. The other end of the primary winding of the second balancer transformer T11 is connected to the other end of the lamp L6.

  The secondary windings of the first balancer transformers T3 to T5 and the secondary windings of the second balancer transformers T6 to T11 are connected in series so as to form one closed loop. By this closed loop, the current flowing through the secondary windings of the first balancer transformers T3 to T5 and the second balancer transformers T6 to T11 is made uniform, so that the current flowing through the primary winding of each balancer transformer is also As a result, the current flowing through the lamps L1 to L6 is made uniform.

  In addition, when one lamp is connected to all balancer transformers, it is not necessary to pass a large amount of current to the secondary winding side, so the primary and secondary windings of the balancer transformer The turns ratio is less than 1: 1. In the present embodiment, since two currents flow through the primary windings of the first balancer transformers T3 to T5, the first balancer transformer T6 to T11 is used as a reference. The winding ratio of the transformers T3 to T5 is ½. For example, if the turn ratio of the second balancer transformer is 2: 1, the turn ratio of the first balancer transformer is 4: 1. As a result, an appropriate current flows in the closed loop.

  In such a lamp lighting device, compared with the prior art, it is almost the same in that the current flowing to the lamp is made uniform by a closed loop, but the number of balancer transformers on the left side is halved, so the cost is reduced. Is possible.

  In the example described above, the number of lamps connected to the primary winding of the first balancer transformer is two, but may be two or more. In that case, the cost reduction effect is increased. In general, when N, the winding ratio is 1 / N.

[Embodiment 2]
In the first embodiment, since only the balancer transformer on the left side of the lamp is reduced, luminance variations tend to occur on the left side of the lamp. In addition, the lamps arranged at the upper and lower ends of the lamp bundle have larger variations in heat and parasitic capacitance between the reflector and the lamp than the lamps arranged inside them. Variations are likely to occur. In order to improve such a point, the second embodiment of the present invention is preferable.

  As shown in FIG. 2, the lamp lighting device according to the second embodiment of the present invention includes AC power supplies V11 and V12, lamps L11 to L16 which are, for example, cold cathode ray tubes, main transformers T31 and T32, The first balancer transformers T29 and T30 and the second balancer transformers T21 to T28 are provided.

  The AC power supply V11 is connected to the primary winding of the main transformer T31. One end of the secondary winding of the main transformer T31 is grounded, and the other end is one end of the primary winding of the second balancer transformer T21, one end of the primary winding of the second balancer transformer T22, One end of the primary winding of the second balancer transformer T23, one end of the primary winding of the first balancer transformer T29, and one end of the primary winding of the second balancer transformer T24. The other end of the primary winding of the second balancer transformer T21 is connected to one end of the lamp L11. The other end of the primary winding of the second balancer transformer T22 is connected to one end of the lamp L12. Further, the other end of the primary winding of the second balancer transformer T23 is connected to one end of the lamp L13. The other end of the primary winding of the first balancer transformer T29 is connected to one ends of the lamps L14 and L15. The other end of the primary winding of the second balancer transformer T24 is connected to one end of the lamp L16.

  The AC power supply V12 is connected to the primary winding of the main transformer T32 and outputs a voltage having the same phase as that of the AC power supply V11. However, since the polarity of the main transformer T32 is different from that of the main transformer T31, a reverse-phase voltage is output to the secondary winding side of the main transformer T32. One end of the secondary winding of the main transformer T32 is grounded, and the other end is one end of the primary winding of the second balancer transformers T25 to T28 and the primary winding of the first balancer transformer T30. It is connected to one end. The other end of the primary winding of the second balancer transformer T25 is connected to the other end of the lamp L11. The other end of the primary winding of the first balancer transformer T30 is connected to the other ends of the lamps L12 and L13. The other end of the primary winding of the second balancer transformer T26 is connected to the other end of the lamp L14. The other end of the primary winding of the second balancer transformer T27 is connected to the other end of the lamp L15. The other end of the primary winding of the second balancer transformer T28 is connected to the other end of the lamp L16.

  The secondary windings of the first balancer transformers T29 and T30 and the secondary windings of the second balancer transformers T21 to T28 are connected in series so as to form one closed loop. This closed loop equalizes the current flowing in the secondary windings of the first balancer transformers T29 and T30 and the second balancer transformers T21 to T28, so that the current flowing in the primary winding of each balancer transformer is also As a result, the current flowing through the lamps L11 to L16 is made uniform.

  In the present embodiment, the outermost lamps L11 and L16 tend to vary in the flowing current due to various influences as described above. Therefore, for each of these lamps, one balancer transformer is connected to both ends, and the current balance is adjusted individually. On the other hand, the lamps L12 to L15 between these lamps L11 and L16 are less susceptible to external influences than the lamps L11 and L16. Therefore, some balancers and transformers are integrated to reduce costs. In particular, unlike the first embodiment, the first balancer transformer for driving two lamps is not biased to one side, but the first balancer transformer is arranged alternately on the left and right. . Therefore, even if luminance variations occur due to variations in current balance that are likely to occur when two lamps are driven, it is possible to make it difficult to understand as a whole.

  However, the number of balancer transformers in the first embodiment is 3, whereas the number of balancer transformers in the present embodiment is 2.

  The winding ratio of the first balancer / transformer is the same as that of the first balancer / transformer of the first embodiment. The number of lamps connected to the first balancer / transformer is the same as in the first embodiment.

[Embodiment 3]
In the first embodiment, an example of differential driving is shown, but there are cases where differential driving is not adopted. In the present embodiment, an example of a lamp lighting device when differential driving is not performed will be described.

  As shown in FIG. 3, the lamp lighting device according to the third embodiment of the present invention includes an AC power source V21, lamps L21 to L26 which are, for example, cold cathode ray tubes, a main transformer T33, and a first balancer. -It has transformers T41 to T43 and second balancer transformers T44 to T49.

  The AC power supply V21 is connected to the primary winding of the main transformer T33. One end of the secondary winding of the main transformer T33 is grounded, and the other end is one end of the primary winding of the first balancer transformer T41, one end of the primary winding of the first balancer transformer T42, One balancer transformer T43 is connected to one end of the primary winding. The other end of the primary winding of the first balancer transformer T41 is connected to one ends of the lamps L21 and L22. The other end of the primary winding of the first balancer transformer T42 is connected to one ends of the lamps L23 and L24. Further, the other end of the primary winding of the first balancer transformer T43 is connected to one ends of the lamps L25 and L26.

  The other end of the lamp L21 is connected to one end of the primary winding of the second balancer transformer T44, and the other end of the primary winding of the second balancer transformer T44 is grounded. The other end of the lamp L22 is connected to one end of the primary winding of the second balancer transformer T45, and the other end of the primary winding of the second balancer transformer T45 is grounded. The other end of the lamp L23 is connected to one end of the primary winding of the second balancer transformer T46, and the other end of the primary winding of the second balancer transformer T46 is grounded. The other end of the lamp L24 is connected to one end of the primary winding of the second balancer transformer T47, and the other end of the primary winding of the second balancer transformer T47 is grounded. The other end of the lamp L25 is connected to one end of the primary winding of the second balancer transformer T48, and the other end of the primary winding of the second balancer transformer T48 is grounded. The other end of the lamp L26 is connected to one end of the primary winding of the second balancer transformer T49, and the other end of the primary winding of the second balancer transformer T49 is grounded.

  The secondary windings of the first balancer transformers T41 to T43 and the secondary windings of the second balancer transformers T44 to T49 are connected in series so as to form one closed loop. By this closed loop, the current flowing through the secondary windings of the first balancer transformers T41 to T43 and the second balancer transformers T44 to T49 is made uniform, so that the current flowing through the primary winding of each balancer transformer is also As a result, the current flowing through the lamps L21 to L26 is made uniform. Thus, the function as a balancer is the same as that of the first embodiment.

  As described above, in this embodiment, the AC power supply and the main transformer are eliminated. However, since it is not differential driving, it is necessary to increase the breakdown voltage of the first balancer transformers T41 to T43 and the second balancer transformers T44 to T49.

  The winding ratio of the first balancer / transformer is the same as that of the first balancer / transformer of the first embodiment. The number of lamps connected to the first balancer / transformer is the same as in the first embodiment. The effect of reducing the number of transformers is the same as in the first embodiment.

[Embodiment 4]
In the third embodiment, an example in which the AC power source and the main transformer are arranged on the first balancer transformer side connected to the plurality of lamps and the second balancer transformer side is grounded is shown. In some cases, the first balancer transformer side is grounded, and the AC power source and the main transformer are arranged on the second balancer transformer side. In the present embodiment, the latter type of lamp lighting device will be described.

  As shown in FIG. 4, the lamp lighting device according to the fourth embodiment of the present invention includes an AC power supply V31, lamps L31 to L36 which are, for example, cold cathode ray tubes, a main transformer T34, and a first balancer. -It has transformers T51 to T53 and second balancer transformers T54 to T59.

  The AC power supply V31 is connected to the primary winding of the main transformer T34. One end of the secondary winding of the main transformer T34 is grounded, and the other end is one end of the primary winding of the second balancer transformer T54, one end of the primary winding of the second balancer transformer T55, One end of the primary winding of the second balancer transformer T56, one end of the primary winding of the second balancer transformer T57, one end of the primary winding of the second balancer transformer T58, the primary of the second balancer transformer T59 Connected to one end of the winding. The other end of the primary winding of the second balancer transformer T54 is connected to one end of the lamp L31. The other end of the primary winding of the second balancer transformer T55 is connected to one end of the lamp L32. Further, the other end of the primary winding of the second balancer transformer T56 is connected to one end of the lamp L33. The other end of the primary winding of the second balancer transformer T57 is connected to one end of the lamp L34. The other end of the primary winding of the second balancer transformer T58 is connected to one end of the lamp L35. Furthermore, the other end of the primary winding of the second balancer transformer T59 is connected to one end of the lamp L36.

  The other end of the lamp L31 and the other end of the lamp L32 are connected to one end of the primary winding of the first balancer transformer T51, and the other end of the primary winding of the first balancer transformer T51 is grounded. The other end of the lamp L33 and the other end of the lamp L34 are connected to one end of the primary winding of the first balancer transformer T52, and the other end of the primary winding of the first balancer transformer T52 is grounded. The other end of the lamp L35 and the other end of the lamp L36 are connected to one end of the primary winding of the first balancer transformer T53, and the other end of the primary winding of the first balancer transformer T53 is grounded.

  The secondary windings of the first balancer transformers T51 to T53 and the secondary windings of the second balancer transformers T54 to T59 are connected in series so as to form one closed loop. By this closed loop, the current flowing through the secondary windings of the first balancer transformers T51 to T53 and the second balancer transformers T54 to T59 is made uniform, so that the current flowing through the primary winding of each balancer transformer is also As a result, the current flowing through the lamps L31 to L36 is made uniform.

  As described above, in this embodiment, the AC power supply and the main transformer are eliminated. However, since it is not differential driving, it is necessary to increase the breakdown voltage of the first balancer transformers T51 to T53 and the second balancer transformers T54 to T59.

  The winding ratio of the first balancer / transformer is the same as that of the first balancer / transformer of the first embodiment. The number of lamps connected to the first balancer / transformer is the same as in the first embodiment. The effect of reducing the number of transformers is the same as in the first embodiment.

[Embodiment 5]
In the embodiment described above, a plurality of transformers are arranged on both sides of the lamp. However, in order to further reduce the cost, this embodiment employs a lamp lighting device as shown in FIG.

  As shown in FIG. 5, the lamp lighting device according to the fifth embodiment of the present invention includes AC power supplies V41 and V42, lamps L41 to L45, which are, for example, cold cathode ray tubes, main transformers T61 and T68, The first balancer transformer T62 and the second balancer transformers T63 to T67 are provided. The AC power supplies V41 and V42 output voltages having opposite phases.

  The AC power supply V41 is connected to the primary winding of the main transformer T61. One end of the secondary winding of the main transformer T61 is grounded, and the other end is connected to one end of the primary winding of the first balancer transformer T62. The other end of the primary winding of the first balancer transformer T62 is connected to the left terminals of the lamps L41 to L45. In this way, the reverse phase voltage of the AC power supply V41 is applied to the left terminals of the lamps L41 to L45.

  The AC power supply V42 is connected to the primary winding of the main transformer T68. One end of the secondary winding of the main transformer T68 is grounded, and the other end is connected to one end of the primary winding of the second balancer transformers T63 to T67. The other end of the primary winding of the second balancer transformer T63 is connected to the right terminal of the lamp L41. The other end of the primary winding of the second balancer transformer T64 is connected to the right terminal of the lamp L42. The other end of the primary winding of the second balancer transformer T65 is connected to the right terminal of the lamp L43. Further, the other end of the primary winding of the second balancer transformer T66 is connected to the right terminal of the lamp L44. The other end of the primary winding of the second balancer transformer T67 is connected to the right terminal of the lamp L45. In this manner, the reverse phase voltage of the AC power supply V42 is applied to the right terminals of the lamps L41 to L45.

  The secondary winding of the first balancer transformer T62 and the secondary windings of the second balancer transformers T63 to T67 are connected in series so as to form a closed loop. Since the voltage excited in the secondary winding of the first balancer transformer T62 and the voltage excited in the secondary windings of the second balancer transformers T63 to T67 are opposite in phase, the second balancer The secondary windings of the transformers T63 to T67 are connected in the forward direction (in the order of +-), but the secondary winding of the second balancer transformer T63 and the secondary winding of the first balancer transformer T62 The polarity of the connection with the winding and the connection between the secondary winding of the second balancer transformer T67 and the secondary winding of the first balancer transformer T62 are in reverse order (++ or −− order). The current flowing in the secondary winding of the first balancer transformer T62 and the current flowing in the secondary windings of the second balancer transformers T63 to T67 are also in opposite phases.

  By this closed loop, the current flowing through the secondary windings of the first balancer transformer T62 and the second balancer transformers T63 to T67 is made uniform, so the current flowing through the primary winding of each balancer transformer is also made uniform. As a result, the current flowing through the lamps L41 to L45 is made uniform. That is, the luminance balance is achieved on the left and right sides of the lamp.

  As described above, in this embodiment, the lamps L41 to L45 are differentially driven to reduce the number of balancer transformers on the left side of the lamps L41 to L45, thereby reducing the cost.

  The winding ratio of the first balancer / transformer is determined in the same manner as the first balancer / transformer of the first embodiment. The number of lamps connected to the first balancer transformer is also determined in the same manner as in the first embodiment.

  Further, the circuit shown in FIG. 5 can be modified as shown in FIG. The difference between FIG. 5 and FIG. 6 is that (1) instead of the AC power supply V42, the primary winding of the main transformer T68 and the primary winding of the main transformer T61 are connected in reverse polarity and (2) A resistor R1 for current detection is inserted in series in a closed loop, one end of the resistor R1 is grounded, and the other end is connected to the control circuit 11, and the control circuit is connected to the output of the switching circuit 10. 11 is that the switching of the switching circuit 10 is controlled based on the current change detected by the current detection resistor R1, and the drive currents of the lamps L41 to L45 through the main transformers T61 and T68 are made uniform. The switching circuit 10 is connected to another power source and one end of the capacitor 12, and the other end of the capacitor 12 is grounded.

  In the prior art as shown in FIG. 8, since two closed loops are provided, it is necessary to detect and stabilize the current for each, but according to the present embodiment, one current detecting resistor R1 is used. Thus, the left and right currents of the lamps L41 to L45 can be detected.

[Embodiment 6]
FIG. 7 shows a lamp lighting device when the cost of Embodiment 5 is further reduced.

  As shown in FIG. 7, the lamp lighting device according to the sixth embodiment of the present invention includes AC power supplies V43 and V44, lamps L51 to L55 that are, for example, cold cathode ray tubes, main transformers T74 and T75, And balancer transformers T69 to T73. The AC power supplies V43 and V44 output in-phase voltages.

  The AC power supply V43 is connected to the primary winding of the main transformer T74. One end of the secondary winding of the main transformer T74 is grounded, and the other end is connected to the terminals on the left side of the lamps L51 to L55. In this way, the in-phase voltage of the AC power supply V43 is applied to the left terminals of the lamps L51 to L55.

  The AC power supply V44 is connected to the primary winding of the main transformer T75. One end of the secondary winding of the main transformer T75 is grounded, and the other end is connected to one end of the primary winding of the balancer transformers T69 to T73. The other end of the primary winding of the balancer transformer T69 is connected to the right terminal of the lamp L51. The other end of the primary winding of the balancer transformer T70 is connected to the right terminal of the lamp L52. The other end of the primary winding of the balancer transformer T71 is connected to the right terminal of the lamp L53. Further, the other end of the primary winding of the balancer transformer T72 is connected to the right terminal of the lamp L54. The other end of the primary winding of the balancer transformer T73 is connected to the right terminal of the lamp L55. In this way, the reverse phase voltage of the AC power supply V44 is applied to the right terminals of the lamps L51 to L55.

  The secondary windings of the balancer transformers T69 to T73 are connected in series so as to form a closed loop. The secondary windings of the balancer transformers T69 to T73 are connected in the forward direction (+ -order).

  This closed loop makes the current flowing through the secondary windings of the balancer transformers T69 to T73 uniform, so the current flowing through the primary winding of each balancer transformer is also made uniform. As a result, the current flows to the right side of the lamps L51 to L55. The flowing current is made uniform. However, since the transformer is omitted on the left side of the lamps L51 to L55, the cost can be reduced, but the luminance variation becomes large.

[Embodiment 7]
* Looking at FIG. 7 showing the sixth embodiment, since currents of the same phase flow through all of the lamps L51 to L55, the screen is liable to be adversely affected by noise. Therefore, in the present embodiment, the lamp lighting device is configured in two systems so that currents having different phases flow through the lamps arranged side by side.

  As shown in FIG. 8, the lamp lighting device according to the seventh embodiment of the present invention includes AC power supplies V45 and V46 for the first system, AC power supplies V47 and V48 for the second system, Lamps L56 to L58 for the first system, which are cold cathode ray tubes, lamps L59 to L61 for the second system, main transformers T76 and T77 for the first system, and mains for the second system Transformers T78 and T79, first system balancer transformers T80 to T82, and second system balancer transformers T83 to T85. The AC power supplies V45 and V46 output in-phase voltages. The AC power supplies V47 and V48 output in-phase voltages. Further, the AC power supplies V45 and V46 and the AC power supplies V47 and V48 output voltages having opposite phases.

  The AC power supply V45 for the first system is connected to the primary winding of the main transformer T76 for the first system. One end of the secondary winding of the main transformer T76 for the first system is grounded, and the other end is connected to the left terminals of the lamps L56 to L58 for the first system. Thus, the in-phase voltage of the AC power supply V45 for the first system is applied to the terminals on the left side of the lamps L56 to L58 for the first system.

  The AC power supply V46 for the first system is connected to the primary winding of the main transformer T77 for the first system. One end of the secondary winding of the main transformer T77 for the first system is grounded, and the other end is connected to one end of the primary winding of the balancer transformers T80 to T82 for the first system. . The other end of the primary winding of the balancer transformer T80 for the first system is connected to the right terminal of the lamp L56 for the first system. The other end of the primary winding of the first system balancer transformer T81 is connected to the right terminal of the lamp L57. The other end of the primary winding of the balancer transformer T82 for the first system is connected to the right terminal of the lamp L58 for the first system. In this way, the reverse phase voltage of the AC power supply V46 for the first system is applied to the terminals on the right side of the lamps L56 to L58.

  The AC power supply V47 for the second system is connected to the primary winding of the main transformer T78 for the second system. One end of the secondary winding of the main transformer T78 for the second system is grounded, and the other end is connected to the left terminals of the lamps L59 to L61 for the second system. In this way, the in-phase voltage of the AC power supply V47 for the second system is applied to the left terminals of the lamps L59 to L61 for the second system.

  The AC power supply V48 for the second system is connected to the primary winding of the main transformer T79 for the second system. One end of the secondary winding of the main transformer T79 for the second system is grounded, and the other end is connected to one end of the primary winding of the balancer transformers T83 to T85 for the second system. . The other end of the primary winding of the balancer transformer T83 for the second system is connected to the right terminal of the lamp L59 for the second system. The other end of the primary winding of the second balancer transformer T84 is connected to the right terminal of the lamp L60. The other end of the primary winding of the balancer transformer T85 for the second system is connected to the right terminal of the lamp L61 for the second system. As described above, the reverse phase voltage of the AC power supply V48 for the second system is applied to the right terminals of the lamps L59 to L61.

  In this way, currents in opposite phases flow through the lamps L56 through L58 of the first system and the lamps L59 through L61 of the second system.

  The secondary windings of the balancer transformers T80 to T85 are connected in series so as to form a closed loop. However, the voltage excited in the secondary windings of the balancer transformers T80 to T82 for the first system and the voltage excited in the secondary windings of the balancer transformers T83 to T85 for the second system Since the phases are reversed, the secondary winding of the balancer transformer T80 and the secondary winding of the balancer transformer T83 are connected in reverse order (--order), and the secondary winding of the balancer transformer T83 and the balancer transformer The polarity of the secondary winding of the transformer T81 is connected in reverse order (++ order), and the secondary winding of the balancer transformer T81 and the secondary winding of the balancer transformer T84 are in reverse order (--order). ), The secondary winding of the balancer transformer T84 and the secondary winding of the balancer transformer T82 are connected in reverse order (in the order of ++), and the secondary winding of the balancer transformer T82 and the balancer transformer Dora The polarity of the secondary winding of the transformer T85 is connected in the reverse order (the order of-), and the secondary winding of the balancer transformer T85 and the secondary winding of the balancer transformer T80 are in the reverse order (the order of ++) ). However, because the direction of the current flowing in the closed loop is aligned, if the connection method of the primary winding and the lamp of the balancer transformer is reversed one by one, the closed loop of the secondary winding is reversed in this order. You don't have to.

  This closed loop makes the current flowing through the secondary windings of the balancer transformers T80 to T85 uniform, so the current flowing through the primary winding of each balancer transformer is also made uniform. As a result, the current flows to the right side of the lamps L56 to L61. The flowing current is made uniform. Since the balancer transformer is not provided on the left side of the lamps L56 to L61, the current flowing to the left side of the lamp varies, but the lamps are arranged so that the phases are staggered as described above. Noise generated by the drive waveform can be canceled and adverse effects on the screen can be suppressed.

[Embodiment 8]
* In the seventh embodiment, an embodiment in which a balancer transformer is not provided on the left side of the lamp is shown. However, in this embodiment, an example in which a balancer transformer is also provided on the left side of the lamp is shown.

  As shown in FIG. 9, the lamp lighting device according to the eighth embodiment of the present invention includes AC power supplies V51 and V52 for the first system, AC power supplies V53 and V54 for the second system, Lamps L62 to L64 for the first system, which are cold cathode ray tubes, lamps L65 to L67 for the second system, main transformers T94 and T95 for the first system, and mains for the second system Transformers T96 and T97, balancer transformers T86 to T89 for the first system, and balancer transformers T90 to T93 for the second system. The AC power supplies V51 and V53 output in-phase voltages. The AC power supplies V52 and V54 output in-phase voltages. Further, the AC power supplies V51 and V53 and the AC power supplies V52 and V54 output voltages having opposite phases.

  The AC power supply V51 for the first system is connected to the primary winding of the main transformer T94 for the first system. One end of the secondary winding of the main transformer T94 for the first system is grounded, and the other end is connected to one end of the primary winding of the balancer transformer T86 for the first system. The other end of the primary winding of the balancer transformer T86 for the first system is connected to the terminals on the left side of the lamps L62 to L64 for the first system. In this way, the reverse-phase voltage of the first system AC power supply V51 is applied to the left terminals of the first system lamps L62 to L64.

  The AC power supply V52 for the first system is connected to the primary winding of the main transformer T95 for the first system. One end of the secondary winding of the main transformer T95 for the first system is grounded, and the other end is connected to one end of the primary winding of the balancer transformers T87 to T89 for the first system. . The other end of the primary winding of the balancer transformer T87 for the first system is connected to the right terminal of the lamp L62 for the first system. The other end of the primary winding of the first system balancer transformer T88 is connected to the right terminal of the lamp L63. The other end of the primary winding of the balancer transformer T89 for the first system is connected to the right terminal of the lamp L64 for the first system. As described above, the reverse phase voltage of the AC power supply V52 for the first system is applied to the right terminals of the lamps L62 to L64.

  The AC power supply V53 for the second system is connected to the primary winding of the main transformer T96 for the second system. One end of the secondary winding of the main transformer T96 for the second system is grounded, and the other end is connected to one end of the primary winding of the balancer transformer T90 for the second system. The other end of the primary winding of the balancer transformer T90 for the second system is connected to the terminals on the left side of the lamps L65 to L67 for the second system. In this way, the reverse-phase voltage of the second system AC power supply V53 is applied to the left terminals of the second system lamps L65 to L67.

  The AC power supply V54 for the second system is connected to the primary winding of the main transformer T97 for the second system. One end of the secondary winding of the main transformer T97 for the second system is grounded, and the other end is connected to one end of the primary winding of the balancer transformers T91 to T93 for the second system. . The other end of the primary winding of the balancer transformer T91 for the second system is connected to the right terminal of the lamp L65 for the second system. The other end of the primary winding of the second balancer transformer T92 is connected to the right terminal of the lamp L66. The other end of the primary winding of the balancer transformer T93 for the second system is connected to the right terminal of the lamp L67 for the second system. In this way, the reverse phase voltage of the AC power supply V54 for the second system is applied to the right terminals of the lamps L65 to L67.

  In this way, currents in opposite phases flow through the lamps L62 to L64 of the first system and the lamps L65 to L67 of the second system.

  The secondary windings of the balancer transformers T86 to T93 are connected in series so as to form a closed loop. However, the voltage excited in the secondary windings of the balancer transformers T86 to T89 for the first system and the voltage excited in the secondary windings of the balancer transformers T90 to T93 for the second system Since the phase is reversed, the secondary winding of the balancer transformer T86 and the secondary winding of the balancer transformer T90 are connected in reverse polarity (--order), and the secondary winding of the balancer transformer T90 and the balancer transformer The polarity of the secondary winding of the transformer T93 is connected in the reverse order (the order of ++), and the secondary winding of the balancer transformer T93 and the secondary winding of the balancer transformer T89 are in the reverse order (the order of-). ), And the secondary winding of the balancer transformer T89 and the secondary winding of the balancer transformer T92 are connected in reverse order (in the order of ++). The secondary winding of the balancer transformer T92 and the balancer transformer Dora The polarity of the secondary winding of the transformer T88 is connected in the reverse order (the order of-), and the secondary winding of the balancer transformer T88 and the secondary winding of the balancer transformer T91 are in the reverse order (++ order). ), The secondary winding of the balancer transformer T91 and the secondary winding of the balancer transformer T87 are connected in reverse order (--order), and the secondary winding of the balancer transformer T87 and the balancer The polarity is connected to the secondary winding of the transformer T86 in the reverse order (++ order).

  This closed loop makes the current flowing through the secondary windings of the balancer transformers T86 to T93 uniform, so the current flowing through the primary winding of each balancer transformer is also made uniform, and as a result, the current flowing through the lamps L62 to L67. Is made uniform. That is, variations in luminance can be suppressed. Since balancer transformers are arranged at both ends of the lamp, the luminance balance is better than that of the seventh embodiment. However, the balancer transformer T86 and T90 winding ratios are determined in the same manner as the first balancer transformer of the first embodiment. The number of lamps connected to the first balancer transformer is also determined in the same manner as in the first embodiment.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, the number of lamps is not limited to 5 or 6, and other lamps can be applied. In this case, not only the arrangement of the first balancer transformer for driving the N lamps is alternated between the left and right sides, but also the second balancer transformer is sandwiched so that the N lamps are not continuous. By doing so, it is possible to further suppress variations in luminance. However, if the number of second balancer transformers is increased, the effect of cost reduction is reduced. Therefore, the entire configuration may be determined in consideration of the balance between luminance balance (current balance) and cost reduction.

  In the first and second embodiments, the closed loop is connected to all the secondary windings of the balancer transformer connected to the left and right of the lamp. You may make it divide. Furthermore, in the first embodiment, the balancer transformers T6 to T11, the main transformer T2, and the AC power supply V2 connected to the right side of the lamp may be grounded.

  Further, the AC power source is an AC power source for driving the lamp, and in some cases, a portion including the main transformer may be called an AC power source.

It is a figure which shows the lamp lighting device which concerns on the 1st Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 2nd Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 3rd Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 4th Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 5th Embodiment of this invention. It is a figure which shows the modification of the lamp lighting device which concerns on the 5th Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 6th Embodiment of this invention. It is a figure which shows the modification of the lamp lighting device which concerns on the 7th Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on the 8th Embodiment of this invention. It is a figure which shows the lamp lighting device which concerns on a prior art.

Explanation of symbols

V1, V2, V11, V12, V21, V31, V41, V42, V43, V44, V45, V46, V47, V48, V51, V52, V53, V54 AC power supplies T1, T2, T31, T32, T33, T34, T61 , T68, T74, T75, T76, T77, T78, T79, T94, T95, T96, T97 Main transformers T3 to T5, T29 and T30, T41 to T43, T51 to T53, T62 First balancer transformers T6 to T6 T11, T21 to T28, T44 to T49, T54 to T59, T63 to T67 Second balancer transformers T69 to T73, T80 to T85, T86 to T93 Balancer transformers L1 to L6, L11 to L16, L21 to L26, L31 Thru L36, L41 thru L45 L51 to L55, L56 to L61, L62 to L67 lamp 10 switching circuit 11 the control circuit 12 the capacitor R1 for current detection resistor

Claims (9)

A lamp lighting device that drives a plurality of lamps in parallel,
A plurality of balancer transformers connected to a plurality of lamps including a first lamp and a second lamp and adjusting a current amount between the lamps;
An AC power source connected to at least one terminal of the plurality of lamps via the balancer transformer;
Have
The balancer transformer has a primary winding and a secondary winding,
The first terminals of the first lamp and the second lamp are respectively connected to primary windings of different balancer transformers,
A second terminal of the first lamp and the second lamp is connected to a common primary winding of the balancer transformer;
The lamp lighting device, wherein secondary windings of at least two balancer transformers are connected in series. The AC power supply is connected to the other end of the primary winding of the balancer transformer connected to the first terminal of the first lamp and the second lamp;
The lamp lighting device according to claim 1, wherein the other end of the primary winding of the balancer transformer connected to the second terminal of the first lamp and the second lamp is grounded. The AC power source is connected to the other end of the primary winding of the balancer transformer connected to the second terminal of the first lamp and the second lamp;
The lamp lighting device according to claim 1, wherein the other end of the primary winding of the balancer transformer connected to the first terminal of the first lamp and the second lamp is grounded. A balancer transformer connected to the first lamp and the second lamp for adjusting the amount of current between the lamps;
An AC power source connected to at least one terminal of the first and second lamps via the balancer transformer;
Have
The balancer transformer has a primary winding and a secondary winding,
One end of the first lamp and the second lamp is connected to a common primary winding of the balancer transformer,
The other ends of the first lamp and the second lamp are wired so that current flows independently,
A plurality of sets of the first lamp and the second lamp exist, and a secondary winding of the balancer transformer is connected to form a closed loop. A lamp lighting device that drives a plurality of lamps in parallel and differentially,
A plurality of balancer transformers connected to the plurality of lamps including a first lamp and a second lamp for adjusting a current amount between the lamps;
The balancer transformer has a primary winding and a secondary winding,
The first terminals of the first lamp and the second lamp are respectively connected to first terminals of primary windings of different balancer transformers,
A second terminal of the first lamp and the second lamp is connected to a first terminal of a primary winding of the common balancer transformer;
A first phase current is supplied to a second terminal of the primary winding of the balancer transformer connected to the first terminal of the first lamp and the second lamp,
A current having a phase opposite to the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the second terminal of the first lamp and the second lamp. And
The lamp lighting device, wherein the secondary windings of at least two balancer transformers are connected in series. A lamp lighting device that drives a plurality of lamps in parallel and differentially,
A plurality of balancer transformers connected to the plurality of lamps including the first to fourth lamps for adjusting a current amount between the lamps;
AC power supply connected to both terminals of the plurality of lamps via the balancer transformer,
Have
The balancer transformer has a primary winding and a secondary winding,
The first terminals of the first lamp and the second lamp are respectively connected to primary windings of different balancer transformers,
A second terminal of the first lamp and the second lamp is connected to a common primary winding of the balancer transformer;
The first terminals of the third lamp and the fourth lamp are respectively connected to primary windings of different balancer transformers,
The second terminals of the third lamp and the fourth lamp are connected to the primary winding of the common balancer transformer,
The secondary windings of at least two of the balancer transformers are connected in series,
The first terminals of the first lamp and the second lamp are respectively arranged to face the same direction,
The second terminals of the third lamp and the fourth lamp are respectively arranged to face the same direction,
The first terminal of the first lamp and the second lamp and the first terminal of the third lamp and the fourth lamp are arranged in opposite directions. The lamp lighting device characterized by this. The primary winding of another said balancer transformer is respectively connected to both terminals of two lamps arranged at both ends among the plurality of lamps arranged in parallel. The lamp lighting device according to any one of 5 and 6. A lamp lighting device that drives a plurality of lamps in parallel and differentially,
A plurality of balancer transformers connected to the plurality of lamps including a first lamp and a second lamp for adjusting a current amount between the lamps;
The balancer transformer has a primary winding and a secondary winding,
The first terminals of the first lamp and the second lamp are respectively connected to first terminals of primary windings of different balancer transformers,
A second terminal of the first lamp and the second lamp is connected to a first terminal of a primary winding of the common balancer transformer;
A first phase current is supplied to a second terminal of the primary winding of the balancer transformer connected to the first terminal of the first lamp and the second lamp,
A current having a phase opposite to the first phase is supplied to the second terminal of the primary winding of the balancer transformer connected to the second terminal of the first lamp and the second lamp. And
The lamp lighting device characterized in that the secondary winding of the balancer transformer is connected in a closed loop. Including a current detection resistor in the closed loop;
The lamp lighting device according to claim 8, further comprising: a control circuit that controls an AC power source connected to the lamp lighting device based on a signal from the current detection resistor.

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