JP2008210856A - Electromagnetic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic device with enhanced workability for fitting and electrical connection that requires no winding work of a primary coil. <P>SOLUTION: A transformer is comprised of a secondary coil L2 for high voltage that a square wire is wound around the side face of a rod-like ferrite core 11 in one layer in edgewise manner and a primary coil L1 that is formed side by side on the low-voltage side of the secondary coil L2 on the side face of the ferrite core 11. The primary coil L1 is made by forming a coil pattern by printing it on an insulating coil substrate 14. Since the primary coil L1 is thus formed on the insulating coil substrate 14 by printing, the workability of fitting the primary coil L1 can be improved and the excessive work of winding thereof can be eliminated because the primary coil L1 and the edgewise wound secondary coil L2 are combined electromagnetically. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic device for generating a high voltage pulse voltage such as a lamp lighting device for lighting a high pressure discharge lamp.

The conventional electromagnetic device does not use a bobbin serving as an insulating member on the side surface of the rod-shaped ferrite core, and wraps a secondary coil for high voltage in which a flat wire is wound edgewise in a single layer. The primary coil is wound on the upper layer of the secondary coil, and the end portion of the primary coil is further routed to the low voltage end portion side of the secondary coil to enhance the insulation function. (For example, Patent Document 1)
JP 2006-108721 A

  In the technique of Patent Document 1 described above, since the primary coil is wound on the upper layer of the secondary coil, it is only necessary to fix the position with an adhesive or the like at the start and end of winding of the primary coil. Or the winding operation | work of a primary coil is required and there existed a subject that it became a factor of a man-hour increase.

  An object of the present invention is to provide an electromagnetic device that eliminates the winding work of the primary coil and improves the workability of attaching the primary coil.

  In order to solve the above-described problems, in the electromagnetic device according to the present invention, a magnetic body, a secondary coil for generating a high voltage in which a rectangular wire is wound edgewise on the side surface of the magnetic body, and a side surface of the magnetic body are provided. And a primary coil formed side by side on the low voltage side of the secondary coil, wherein the primary coil is formed on an insulating coil substrate.

  Further, the magnetic body, the first and second secondary coils for generating a high voltage in which a rectangular wire is edgewise wound on the side surface of the magnetic body, and the side surfaces of the magnetic body, the first and first A primary coil interposed on the low-voltage side of the secondary coil, and the primary coil is formed on an insulating coil substrate.

  According to the present invention, the primary coil is formed on the insulating substrate, and the primary coil and the secondary coil wound in an edgewise manner are electromagnetically coupled, thereby simplifying the formation and attachment of the primary coil. be able to.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  1 to 11 are diagrams for explaining one embodiment of the present invention. FIG. 1 is a perspective view, FIG. 2 is a perspective view of FIG. 1 connected to a printed circuit board, and FIG. 3 is a front view of FIG. 4 is a side view of FIG. 2, FIG. 5 is an exploded front view of the ferrite core of FIG. 1, FIG. 6 is a perspective view of the secondary coil of FIG. 1, FIG. 7 is a side view of FIG. FIG. 9 is a left side view of FIG. 8, FIG. 10 is a right side view of FIG. 8, and FIG. 11 is a circuit of FIG.

First, in FIGS. 1 to 3, reference numeral 11 denotes a drum-shaped ferrite core having a specific resistance of, for example, 10 ³ Ω / m or more. As shown in FIG. 5, one end of the ferrite core 11 is formed integrally with the flange 11 a, and the other end is formed of a flange 11 c in which a fitting hole 11 b that fits into the ferrite core 11 is formed. The ferrite core 11 has a drum shape with flanges 11a and 11c.

  A mounting hole 12a of the secondary coil L2 is inserted into the ferrite core 11. As shown in FIGS. 6 and 7, the secondary coil L2 is formed by edgewise winding a flat wire without using a bobbin as an insulating member. The mounting hole 12a is formed when edgewise winding is performed. The secondary coil L2 is an insulating coated electric wire whose core wire is covered with an insulating coating, and both the coil ends 12b and 12c have the insulating coating removed. The secondary coil L2 is attached to the ferrite core 11 so that the low voltage side of the secondary coil L2 is on the flange 11a side.

  Between the low voltage side of the secondary coil L2 and the flange 11a of the ferrite core 11, the insertion hole 15 of the insulating coil substrate 14 on which the primary coil L1 is formed as shown in FIGS. It is interposed in a state inserted in the core 11. The coil substrate 14 is formed with a coil pattern 14a constituting a part of the primary coil on one surface and a coil pattern 14b constituting the primary coil on the other surface by printing. One end of each of the coil patterns 14a and 14b is electrically connected through the through hole 14c, the other end of the coil pattern 14a is integrated with the connection pattern 14d, and the other end of the coil pattern 14b is integrated with the connection pattern 14e. Connected.

  As a result, the primary coil L1 is formed as a three-turn coil in which two turns on one side and one turn on the other side are combined. 14f formed in the vicinity of each of the connection patterns 14d and 14e of the coil substrate 14 is a connection pattern for connecting to the coil end 12c of the secondary coil L2.

  In a state of being inserted into the ferrite core 11, the primary coil L1 and the secondary coil L2 are connected to the main circuit board 21 on which the circuit pattern 21a shown in FIGS. 3 and 4 is formed. At this time, the coil end 12c of the secondary coil L2 is connected in advance to the connection pattern 14f, thereby contributing to the workability of the connection. The coil end 12b on the high voltage side of the secondary coil L2 is supplied to, for example, a high pressure discharge lamp via the power supply line 22.

  The secondary coil L2 and the primary coil L1 are electromagnetically coupled through the ferrite core 11, whereby the transformer T of the circuit shown in FIG.

  By the way, the secondary coil L1 can make edgewise winding small without reducing the cross-sectional area on the side surface of the ferrite core 11. For example, when a voltage of several hundred volts is applied to the connection patterns 14d and 14e of the primary coil L1, a high voltage of several kV to several tens of kV may be generated in a small state at both ends of the secondary coil L2. It becomes possible. In this case, the primary coil L1 and the secondary coil L2 form a magnetic path having the ferrite core 11 as a coaxial.

  As described above, the primary coil L1 is arranged to be on the low voltage side of the secondary coil L2. For example, when a high pressure discharge lamp is turned on, the primary coil L1 becomes several hundred volts, whereas the secondary coil L2 has a high voltage side of several kV to several tens kV, and the primary coil L1, the secondary coil. There is a possibility that dielectric breakdown may occur between L2. For this reason, the distance from the coil end 12b on the high voltage side of the secondary coil L2 to the primary coil L1 is increased to prevent the occurrence of dielectric breakdown.

  In this way, the primary coil is formed on the coil substrate by means such as printing, and is electromagnetically coupled to the primary coil and the secondary coil wound in an edgewise manner, thereby mounting the primary coil and forming the primary coil. This eliminates the need for winding work.

  FIG. 12 is a circuit diagram for explaining an example in which the embodiment of the electromagnetic device of the present invention described in FIGS. 1 to 10 is applied to a lighting device for a high-pressure discharge lamp.

  In FIG. 12, the power source Vin generates a DC voltage. The power source Vin generates constant power. The power source Vin is constituted by, for example, an output smoothing capacitor of a constant power control chopper circuit.

  The positive output terminal of the power supply Vin is connected to the drains of the transistors Q1 and Q3 via the power supply line. The negative output terminal of the power source Vin is connected to the sources of the transistors Q2 and Q4 via a reference potential line. The source of the transistor Q1 and the drain of the transistor Q2 are connected to each other. Further, the source of the transistor Q3 and the drain of the transistor Q4 are connected to each other.

  These transistors Q1 to Q4 constitute a bridge type DC / AC inverter that converts a DC voltage from the power source Vin into an AC voltage.

  A first connection point P1 between the source of the transistor Q1 and the drain of the transistor Q2 is connected to the transistor Q3 via a first circuit portion including one connection pattern 14d of the primary coil L1, the first-stage booster circuit 121, and the capacitor C1. Are connected to a second connection point P2 between the source of the transistor Q4 and the drain of the transistor Q4. The other connection pattern 14e of the primary coil L1 is connected to the first stage booster circuit 121. In addition, a second circuit unit including the secondary coil L2 and the lamp LP is connected between the first connection point P1 and the second connection point P2. A high pressure discharge lamp is used as the lamp LP.

  Here, the transformer T in FIG. 12 corresponds to the electromagnetic device described in FIGS. 1 to 10 including the primary coil L1, the secondary coil L2, and the ferrite core 11.

  The coil La of the first stage booster circuit 121 is connected between the connection pattern 14e of the primary coil L1 and the capacitor C1. The connection pattern 14d of the primary coil L1 connects the discharge gap G and the capacitor C2 in series, and is connected to one end of the transformer Lb and the connection pattern 14e of the primary coil L1. The other end of the transformer Lb is connected to a connection point between the discharge gap G and the capacitor C2 via a diode D1 having the polarity shown. The coils La and Lb constitute a transformer.

  The capacitor C1 is provided for vibration waveform formation and current limitation. The transformer T constituted by the primary coil L1 and the secondary coil L2 has the primary coil L1 as the primary side and the secondary coil L2 as the secondary side. The number of turns of the secondary coil L2 is set to n times (n is a positive number) the number of turns of the primary coil L1. As the turn ratio n, for example, a value of several times to several hundred times is set.

  At the time of starting the lamp, the power source Vin for supplying a positive output to the power supply line and a negative output to the reference potential line is supplied to the transistors Q1 to Q4 constituting the DC / AC inverter. At the start of lighting of the lamp LP, the first high frequency is set as the drive frequency of the transistors Q1 to Q4. This first high-frequency control signal is supplied to the transistors Q1 to Q4 to turn them on / off.

  The bridge circuit simultaneously controls on / off of the transistors Q1, Q4 and simultaneously controls on / off of the transistors Q2, Q3. In order to prevent a short circuit, the transistors Q1 to Q4 are all turned off for a short time.

  When the transistors Q1 and Q4 are on, a current flows from the positive output terminal of the power source Vin to the negative output terminal through the transistor Q1, the primary coil L1, the coil La, the capacitor C1, and the transistor Q4. On the contrary, when the transistors Q2 and Q3 are on, a current flows from the positive output terminal of the power source Vin to the negative output terminal via the transistor Q3, the capacitor C1, the coil La, the primary coil L1, and the transistor Q2. .

  When the transistors Q1 and Q4 are on, the capacitor C1 is charged via the primary coil L1 and the coil La, and the terminal voltage of the capacitor C1 rises to the voltage Vin of the power source Vin. Next, due to the back electromotive force generated in the primary coil L1 and the coil La, the voltage VL1 + VLa generated in the primary coil L1 and the coil La is added to the terminal voltage of the capacitor C1, and rises to Vin + VL1 + VLa. Next, free vibration occurs between the primary coil L1, the coil La, and the capacitor C1, and the terminal voltage of the capacitor C1 converges to a predetermined value while changing the polarity. Even when the transistors Q2 and Q3 are on, the same operation as when the transistors Q1 and Q4 are on is performed.

  Thereby, the voltage according to the turns ratio can be generated in the coil Lb by the voltage generated in the coil La.

  The voltage of the coil Lb is rectified by the diode D1, and charges are accumulated in the capacitor C2. The capacitor C2 is repeatedly charged every time the polarity inversion operation of the bridge circuit is performed in which the transistors Q1 and Q4 and the transistors Q2 and Q3 are turned on and off to switch the conduction path of the bridge circuit. As a result, the terminal voltage of the capacitor C2 gradually increases. When the terminal voltage of the capacitor C2 rises to the gap voltage Vg of the discharge gap G, discharge occurs in the discharge gap G, current flows through the loop of the capacitor C2, the discharge gap G and the primary coil L1, and the secondary coil is caused by electromagnetic induction. A sufficiently large lamp starting voltage is generated at L2. A voltage generated in the secondary coil L2 is applied to the lamp LP.

  Further, since a voltage is also generated in the primary coil L1 every time the polarity inversion operation of the bridge circuit is performed, a voltage corresponding to the turn ratio of the primary coil L1 and the secondary coil L2 is generated in the secondary coil L2, and the lamp LP Applied to both ends.

  Thus, by driving on / off of the transistors Q1, Q4 and the transistors Q2, Q3 at the first high frequency, the first-stage booster circuit 121 performs a boost operation, and the terminal voltage of the capacitor C2 increases. This boosting operation is performed in synchronization with the polarity inversion operation of the bridge circuit. As an example, the capacitor C2 reaches the discharge gap voltage Vg and is discharged by several to tens of thousands of operations.

  As the discharge gap G is discharged, the capacitor C2 voltage is applied to the primary coil L1, a high voltage is generated in the secondary coil L2 by the electromagnetic induction action of the transformer T, and a high voltage is applied to the lamp LP.

  Furthermore, the voltage applied to the primary coil L1 for each polarity reversal operation of the bridge circuit at a time different from such a high voltage generation operation becomes the turn ratio of the primary coil L1 and the secondary coil L2. Accordingly, electromagnetic induction is performed in the secondary coil L2. As a result, a low voltage is generated across the lamp LP.

  That is, every time the polarity inversion operation of the bridge circuit is performed, a low voltage is generated in the secondary coil L2 and can be applied to the lamp LP, and the secondary coil L2 is synchronized with several to tens of thousands of polarity inversion operations. A high voltage is generated and can be applied to the lamp LP. When the lamp LP is lit by the low voltage generated in the secondary coil L2, thereafter, the current flowing through the first circuit portion is sufficiently small, and the secondary coil L2 has a relatively large voltage enough to light the lamp LP. Will not occur.

  In addition, even when the lamp LP is not lit at a low voltage generated in the secondary coil L2, a high voltage is generated in the secondary coil L2 by repeating the polarity reversal operation, so that the lamp LP is reliably lit. . When the lamp LP is turned on, a relatively large voltage that causes the lamp LP to turn on does not occur thereafter in the secondary coil L2.

  As described above, at the time of start-up, the boosting operation is generated in the capacitor C2 and the transformer T is simultaneously boosted by the free vibration operation of the primary coil L1 and the coil La and the capacitor C1 during the polarity inversion operation of the bridge circuit. . During this free vibration, a voltage applied to the coil La is induced in the coil Lb by a boosting action according to the turns ratio of the coils La and Lb. The voltage is rectified by the diode D1 and charged in the capacitor C2. As described above, the free vibrations of the primary coil L1, the coil La, and the capacitor C1 converge until the next polarity inversion, and the current becomes substantially zero.

  The starting voltage to the lamp LP is of two types: a low voltage that can be generated every time the polarity inversion operation of the bridge circuit is performed, and a high voltage that can be generated each time the discharge gap is discharged. Thus, it is possible to start at a low voltage under conditions where the lamp start is likely to occur such as when the lamp temperature is low, and start at a high voltage under conditions where the lamp start is difficult to occur such as when the lamp temperature is high.

  Use of the electromagnetic device of the present invention as the primary coil L1 and the secondary coil L2 constituting the transformer T that generates such a high voltage of the lighting circuit contributes to space saving and improvement in mounting workability. Can do.

  13 to 15 are views for explaining another embodiment of the present invention, FIG. 13 is a perspective view, FIG. 14 is a front view of FIG. 13 in a state connected to a printed circuit board, and FIG. 15 is a circuit of FIG. It is. The same components as those in the above-described embodiment will be described with the same reference numerals. FIG. 13 corresponds to FIG. 1, and FIG. 14 shows a portion corresponding to FIG.

  In this embodiment, a second secondary coil L22 is formed on the opposite side of the first secondary coil L21 across the primary coil L1, and the rectangular wire of the second secondary coil L22 is edgewise. In the mounting hole 11b formed by winding, the ferrite core 11 passing through the first secondary coil L21 and the primary coil L1 is extended so far.

  The second secondary coil L22 is formed by edgewise winding a rectangular wire in a single layer, and allows the ferrite core 11 to pass through an attachment hole formed when edgewise winding is performed. The second secondary coil L22 is an insulating coated electric wire whose core wire is covered with an insulating coating, and both the coil ends 13a and 13b have the insulating coating removed. The second secondary coil L22 is attached to the ferrite core 11 so that the high voltage side of the second secondary coil L22 is on the flange 11a side.

  The primary coil L1, the first secondary coil L21, and the second secondary coil L22 inserted in the ferrite core 11 are connected to the main circuit board 21 on which the circuit pattern 21a shown in FIG. 14 is formed. . At this time, the coil end 12c of the first secondary coil L21 is connected in advance to the connection pattern 14f and the coil end 13a of the second secondary coil L22 is connected in advance to the connection pattern 14g, thereby contributing to improvement in connection workability. The coil end 12b on the high voltage side of the first secondary coil L21 is connected to, for example, one end of a high pressure discharge lamp via the power supply line 221, and the coil end 13b on the high voltage side of the second secondary coil L22 is connected to the power supply line 222. For example, it connects to the other end of a high pressure discharge lamp. The number of turns of the first secondary coil L21 and the second secondary coil L22 is set to n times (n is a positive number) the number of turns of the primary coil L1. As the turn ratio n, for example, a value of several times to several hundred times is set.

  By the way, the secondary coil L1 and the second secondary coil L22 can be reduced in size by edgewise winding without reducing the cross-sectional area on the side surface of the ferrite core 11. For example, when the number of turns of the first secondary coil L21 and the second secondary coil L22 is the same and a voltage of several hundred volts is applied to the connection patterns 14d and 14e of the primary coil L1, the first It becomes possible to generate a high voltage of several kV to several tens of kV at both ends of the secondary coil L21 and the second secondary coil L22 as a high voltage transformer in a small state. In this case, the primary coil L1, the first secondary coil L21, and the second secondary coil L22 form a magnetic path having the ferrite core 11 as a coaxial.

  The low voltage sides of the first secondary coil L21 and the second secondary coil L22 are arranged to be on the primary coil L1 side. For example, when a high pressure discharge lamp is turned on, the primary coil L1 is several hundred volts, whereas the first secondary coil L21 is several kV to several tens kV, and the primary coil L1 and the first coil L1 There is a possibility that a dielectric breakdown occurs between the secondary coil L21 and the secondary coil L21.

  For this reason, the distance from the coil end 12b on the high voltage side of the first secondary coil L21 to the connection patterns 14d and 14e of the primary coil L1 is changed from the coil end 13b on the high voltage side of the second secondary coil L22 to the primary. The distance between the coil L1 and the connection patterns 14d and 14e is increased to prevent dielectric breakdown.

  As described above, the primary coil is formed on the coil substrate by means such as printing, and the first secondary coil L21 and the second secondary coil L22, which are edgewise wound, are electromagnetically coupled by the primary coil L1 and the ferrite core 11. By coupling, it is possible to save the trouble of attaching the first secondary coil L21 and the second secondary coil L22 and winding work for forming the primary coil.

  FIG. 16 is a circuit diagram for explaining an example in which another embodiment relating to the electromagnetic device of the present invention described in FIGS. 13 and 14 is applied to a lighting device for a high-pressure discharge lamp. This circuit diagram is different in that a second secondary coil L22 having the primary coil L1 and the ferrite core 11 in common is formed between the lamp LP and the second connection point P2, and this difference is here. Will be described.

  The number of turns of the first secondary coil L21 and the second secondary coil L22 of the transformer T used in this application example is the same, and the turns are reversed with respect to the primary coil L1. The coil end 12b on the high voltage side of the first secondary coil L21 is connected to one end of the lamp LP, and the coil end 13b on the high voltage side of the second secondary coil L22 is connected to the other end of the lamp LP.

  In this configuration, the voltage generated at the coil end 12b of the first secondary coil L21 and the coil end 13b of the second secondary coil L22 of the transformer T and applied to both ends of the lamp LP is positive and negative. Has polarity. The voltage applied to the lamp LP is a value obtained by adding (subtracting) the voltages generated in the first secondary coil L21 and the second secondary coil L22, respectively. For this reason, if it is applied to the same lamp LP as the voltage generated by the number of turns of the first secondary coil L21 of the above-described embodiment, the number of turns of the first secondary coil L21 is set in this embodiment. The second secondary coil L22 having the same number of turns as the half may be used.

  FIG. 17 is a perspective view for explaining a modification of the present invention. In each of the embodiments described above, the coil end 12b of the secondary coil L2 is connected to the power supply line 22 via the main circuit board 21, but the coil end 12b may be directly connected to the power supply line 22. In this case, it is possible to provide a design margin regarding the withstand voltage of the coil end 12 portion on the high voltage side.

  The present invention is not limited to the above-described embodiment. For example, the first-stage booster circuit 121 and the capacitor c1 shown in FIGS. 12 and 16 can be mounted on the coil substrate 14 on which the primary coil L1 is configured. Also, the electromagnetic device shown in FIGS. 1 and 13 can be housed in a case and filled with a resin or the like to improve insulation.

The perspective view for demonstrating one Embodiment of this invention. The perspective view of FIG. 1 in the state connected to the printed circuit board. The front view of FIG. The side view of FIG. The front view which decomposed | disassembled the ferrite core of FIG. The perspective view of the secondary coil of FIG. The side view of FIG. The perspective view of the primary coil of FIG. The left view of FIG. The right view of FIG. The circuit diagram of FIG. The circuit diagram for demonstrating the application example of the electromagnetic device of FIG. The perspective view for demonstrating other embodiment of this invention. The front view of FIG. 11 in the state connected to the printed circuit board. FIG. 14 is a circuit diagram of FIG. 13. FIG. 14 is a circuit diagram for explaining an application example of the electromagnetic device of FIG. 13. The perspective view for demonstrating the modification of this invention.

Explanation of symbols

L1 Primary coil L2 Secondary coil L21 First secondary coil L22 Second secondary coil 11 Ferrite core 12a Mounting holes 12b, 12c, 13a, 13b Coil end 14 Coil substrate 14a, 14b Coil pattern 14c Through hole 14d, 14e, 14f, 14g Connection pattern 15 Insertion hole 21 Main circuit board 22 Power supply line

Claims (5)

Magnetic material,
A secondary coil for generating a high voltage in which a rectangular wire is wound edgewise on the side surface of the magnetic body;
A primary coil formed side by side on the low-voltage side of the secondary coil on the side surface of the magnetic body;
The electromagnetic device according to claim 1, wherein the primary coil is formed on an insulating coil substrate.   The electromagnetic device according to claim 1, wherein the primary coil is formed on a plurality of surfaces of the coil substrate and connected in series to increase the number of turns.   3. The electromagnetic device according to claim 1, further comprising a circuit board provided with a circuit pattern in which at least one end of the secondary coil and both ends of the primary coil are respectively connected to predetermined locations. 4. . Magnetic material,
First and second secondary coils for generating a high voltage in which a rectangular wire is wound edgewise on the side surface of the magnetic body;
A primary coil located on a side surface of the magnetic body and interposed on the low voltage side of the first and second secondary coils,
The electromagnetic device according to claim 1, wherein the primary coil is formed on an insulating coil substrate.   The electromagnetic device according to claim 1, wherein other circuit components are mounted on the coil substrate in addition to the primary coil.

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