JP2009193877A - Discharge lamp lighting device and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device which suppresses a rise in a high-frequency noise level caused by high-frequency noises flowing from an input terminal into a low-frequency ac power supply, without specifying wiring to adopt. <P>SOLUTION: The discharge lamp lighting device includes a lighting circuit that includes an input terminal 2, a high-frequency cut-off filter 4 connected to the input terminal 2 and including a first inductor L1, a rectifying circuit 5, a smoothing capacitor C2, an inverter circuit 6, a control IC 7, a load circuit 8 connected to an ac output terminal of the inverter circuit 6 and including a resonance circuit composed of a second inductor L2 and a resonance capacitor C3, and an output terminal 9. The discharge lamp lighting device further includes a long, narrow wiring board 1 carrying the lighting circuit. On the wiring board 1, the input terminal 2 and the output terminal 9 are disposed on one longitudinal end of the wiring board 1, the high-frequency cut-off filter 4 is disposed near the input terminal 2, the load circuit 8 is disposed close to the output terminal 9 and to the high-frequency cut-off filter 4, and leakage magnetic flux from the second inductor L2 distributes mainly in the direction parallel with the longitudinal direction of the wiring board 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device including an inverter circuit and a lighting fixture including the same.

  A capacitor input type discharge lamp lighting device is known (see, for example, Patent Document 1). This type of discharge lamp lighting device has the advantage of being small and inexpensive because of its simple circuit configuration, and is mainly used in small lighting fixtures with relatively low load power, but further downsizing and cost reduction Is required. For this reason, the tendency to perform high-density mounting using a small wiring board is strengthened.

JP 2001-283602 A

  However, with the miniaturization of the wiring board, there is a concern that the noise level deteriorates due to the influence of leakage magnetic flux from the ballast inductor of the load circuit. For example, when the wiring board cannot be made into a relatively long and narrow rectangular shape in relation to the installation space for the lighting fixture, or in order to eliminate wiring designation, the input terminal and the output terminal are concentrated on one end side of the long and narrow wiring board. In some cases, the circuit arrangement from the input terminal to the output terminal is U-shaped. For this reason, the high-frequency cut filter disposed on the input terminal side and the load circuit disposed on the output terminal side are often disposed close to each other at substantially opposite positions in the width direction of the wiring board. Since the high frequency cut filter includes an inductor that blocks high frequency, and the load circuit includes an inductor that performs ballast action, leakage flux is generated from the core gap of the inductor that performs ballast action, and the high frequency cut filter. As a result, the high frequency noise is fed back to the power source through the high frequency cut filter, and the high frequency noise flows out from the input terminal to the low frequency AC power source.

  Therefore, noise level deterioration has been avoided by designating in-instrument wiring such as separating the positions of the input terminal and output terminal at both ends in the longitudinal direction of the wiring board. However, depending on the structure of the lighting fixture, there is a case where the designation of the wiring inside the fixture is disliked due to manufacturing reasons, and in such a case, the noise level may be sacrificed.

  The present invention provides a discharge lamp lighting device that suppresses high-frequency noise from flowing from an input terminal to a low-frequency AC power supply when both the input terminal and the output terminal are disposed on one end in the longitudinal direction of the same wiring board. And it aims at providing the lighting fixture provided with this.

  A discharge lamp lighting device of the present invention includes an input terminal connected to a low-frequency AC power source, a high-frequency cut filter including a first inductor connected to the input terminal, a rectifier circuit connected to the input terminal via the high-frequency cut filter, and rectification A smoothing capacitor connected between the DC output terminals of the circuit, an inverter circuit including a switching element and a DC input terminal connected between both ends of the smoothing capacitor, a control IC for controlling the inverter circuit, a second inductor, and a resonant circuit of the resonant capacitor A load circuit connected to the AC output terminal of the inverter circuit, and a lighting circuit having an output terminal for connecting the discharge lamp to the load circuit; the lighting circuit being mounted, the input terminal and the output terminal being in the longitudinal direction of the substrate Located at one end, a high frequency cut filter is placed near the input terminal, and the load circuit is placed near the output terminal. And an elongated wiring board disposed in the vicinity of the high-frequency cut filter in the substrate width direction and disposed so that the leakage flux of the second inductor is distributed mainly in a direction parallel to the longitudinal direction of the substrate. It is characterized by that.

  The present invention allows the following aspects.

  The lighting circuit includes at least an input terminal, a high frequency cut filter, a rectifier circuit, a smoothing capacitor, an inverter circuit, a control IC, a load circuit, and an output terminal. Then, it is mounted on an elongated wiring board. Insert type (insertion type) circuit parts are inserted from the front side of the wiring board and soldered to the backside land, and chip type (surface mount type) circuit parts are placed on the backside land of the wiring board and soldered. A known mounting method can be adopted.

  The input terminal is connected to a low-frequency AC power source such as a commercial AC power source and receives low-frequency input power in the lighting circuit. The input terminal is disposed on one end side in the longitudinal direction of the wiring board.

  The high-frequency cut filter is a circuit means that includes a first inductor and acts so that high-frequency noise does not flow from the lighting circuit to the low-frequency AC power supply side, but the circuit configuration is not particularly limited. The high frequency cut filter is disposed in the vicinity of the input terminal of the wiring board in the longitudinal direction of the board. For example, a common mode choke coil or a single choke coil can be selectively used as the first inductor.

  In addition, the high-frequency cut filter can form various types of known filter circuits by combining the first inductor and one or a plurality of capacitors. Furthermore, if necessary, a surge absorbing element that absorbs an external surge and protects the lighting circuit can be added in parallel to the low-frequency AC power supply.

  The rectifier circuit and the smoothing capacitor constitute a direct current power source that provides direct current power to be input to an inverter circuit described later. When the rectifier circuit and the smoothing capacitor are mounted separately on the front and back of the wiring board, the smoothing capacitor is installed by the heat generated from the rectifier circuit by disposing the rectifying circuit and the smoothing capacitor on the front and back of the board surface of the wiring board. It is possible to suppress an increase in temperature.

  The rectifier circuit is a means for rectifying a low-frequency AC voltage and converting it to a DC voltage. A bridge-type full-wave rectifier circuit is preferable, but a half-wave rectifier circuit can be used if desired. In addition, it is possible to mount the entire rectifier circuit as a chip-type component on the back surface of the wiring board.

  The smoothing capacitor is connected between the DC output terminals of the rectifier circuit to reduce ripples included in the DC output of the rectifier circuit. Using a smoothing capacitor configured as an insert-type component, it can be mounted on the surface of the wiring board. In general, an electrolytic capacitor is used as the smoothing capacitor, but there is a 10 ° C. half law for the lifetime of the electrolytic capacitor. Therefore, since the temperature rise is suppressed by setting the arrangement position of the smoothing capacitor so as not to be superposed as described above, the life of the smoothing capacitor and the discharge lamp lighting device can be avoided. In addition, by setting the capacitance of the smoothing capacitor to an appropriate value, the harmonic distortion applied to the low-frequency AC power supply is reduced even in the capacitor input type discharge lamp lighting device, and the JIS standard (JIS C 61000- 3-2) can be satisfied.

  The inverter circuit is a means for converting the DC voltage smoothed by the smoothing capacitor in the present invention into an AC voltage by switching one or more switching elements, and appropriately adopts various known circuit systems as appropriate. Can do. However, since the circuit configuration is simple and can be obtained at a relatively low cost, a half-bridge type inverter including two switching elements is preferable. It is possible to adopt an insert-type component as the switching element of the inverter circuit.

  The insert-type switching element has a flat shape, and a lead wire protrudes from one end of the flat surface. When such a switching element is mounted on a wiring board, it is conceivable that the two switching elements are mounted in a state where their flat surfaces are parallel to and spaced apart from the side edge of the wiring board. However, in such an arrangement, the switching element on the side edge side of the wiring board may incline during the manufacture of the discharge lamp lighting device and protrude outward from the side edge. As a result, the lighting fixture and the switching element come into contact with each other, and stress may be generated on the land of the switching element, so that the discharge lamp lighting device may break down early. As a countermeasure against this, the switching element located on the side edge side of the wiring board is arranged such that its flat surface is substantially perpendicular to the side edge of the wiring board. As a result, the above-described problems do not occur.

  In addition, if the other switching element located relatively on the center side of the wiring board is disposed so that the plane is substantially parallel to the longitudinal direction of the wiring board, when the switching element is an FET, Since the leakage flux of the second inductor is less likely to be linked to the gate made of metal, power loss caused by linkage is reduced.

  The control IC is a control means for generating a drive signal for driving the switching element to separately control the inverter circuit and for performing a protection operation and a control operation as a discharge lamp lighting device. For example, the protection operation is performed by determining whether or not the lamp is installed and performing a protection operation against the non-installation of the lamp, detecting the half-wave discharge and performing the end-of-life protection operation of the discharge lamp, or detecting the lamp voltage of the discharge lamp. To perform feedback control.

  The control IC is disposed on the other end side in the longitudinal direction of the wiring board and on the surface opposite to the surface on which the input terminal and the output terminal are disposed, that is, the back surface. As a result, the control IC can be separated from the circuit through which the relatively large input / output current flows, and only the small signal patterns can be collected around the control IC. As a result, malfunction of the control IC can be prevented.

  The load circuit includes a resonance circuit of a second inductor and a resonance capacitor, and is connected to the AC output terminal of the inverter circuit. The second inductor has a winding wound around a core having a gap, and takes charge of the ballast action of the discharge lamp. In this inductor, since the core has a gap, when a load current flows, a leakage magnetic flux is generated from the gap and spreads outside the inductor. The leakage magnetic flux is distributed mainly in the front-rear direction without the side legs of the core.

  In the present invention, the second inductor is disposed with its orientation defined so that the leakage magnetic flux is distributed mainly along the longitudinal direction of the wiring board. Therefore, although the load circuit is disposed in the vicinity of the high-frequency cut filter, the position of the load circuit is mainly close in the width direction of the wiring board, so that the leakage flux of the second inductor is interlinked with the first inductor. It becomes difficult to do. As a result, the magnetic coupling between the first and second inductors is substantially not performed, and the high frequency noise flowing out to the input terminal side is significantly reduced.

  Further, the load circuit connects the discharge lamp to the resonance capacitor in parallel when the second inductor acts as a ballast. As a result, a sinusoidal resonance voltage is applied to the discharge lamp. Further, in order to adjust the voltage applied to the filament electrode of the discharge lamp to a desired value, the load circuit is allowed to include a capacitor connected in parallel to the filament electrode.

  The output terminal is a means for connecting the discharge lamp to the load circuit, and is disposed on one end side in the longitudinal direction of the wiring board adjacent to the input terminal in the board width direction. If the discharge lamp is connected to the output terminal, the discharge lamp is connected to a predetermined position of the load circuit. Therefore, it can be started and lit by operating the inverter circuit.

  Further, in order to make the output terminal less susceptible to the influence of the leakage magnetic flux of the second inductor, they are arranged as far apart as possible even though they are close to each other in the overall arrangement of the discharge lamp lighting device. It is preferable to do this. As a result, it is possible to prevent the output line connected to the output terminal from being magnetically coupled to the output line via the second inductor and its leakage magnetic flux and transmitting noise to the output line. The second inductor and the output terminal are separated from each other on the wiring board, so that another circuit component can be disposed in the space generated between them. As a result, noise suppression can be realized while maintaining a high mounting density. For example, a filament capacitor connected in parallel to the filament electrode can be used as the other circuit component.

  The lighting fixture of the present invention comprises: a lighting fixture body; a discharge lamp disposed in the lighting fixture body; and the discharge lamp lighting device according to any one of claims 1 to 4 for lighting the discharge lamp. It is characterized by being.

  In the present invention, the lighting fixture is a concept including all devices using a discharge lamp as a light source, and includes various lighting fixtures for indoor and outdoor use, a marker lamp, a display lamp, a signal device, a chemical reaction device, and the like.

  The luminaire main body is composed of the remaining parts excluding the discharge lamp and the discharge lamp lighting device from the luminaire.

  According to the present invention, the input terminal and the output terminal are arranged on one end side in the longitudinal direction of the elongated wiring board, the high frequency cut filter is arranged in the vicinity of the input terminal, the load circuit is in the vicinity of the output terminal, and the board The second inductor is disposed in the vicinity of the high frequency cut filter in the width direction and the second inductor and the high frequency are disposed so that the leakage flux of the second inductor is mainly distributed in a direction parallel to the longitudinal direction. Since the first inductor of the cut filter is substantially not magnetically coupled via the leakage magnetic flux, a discharge lamp lighting device that suppresses high-frequency noise from flowing out from the input terminal to the low-frequency AC power supply and does not specify wiring And a lighting fixture provided with the same can be provided.

  In addition, since the control IC is disposed on the other end side in the longitudinal direction of the wiring board and on the surface opposite to the surface on which the input terminal and the output terminal are disposed, the control IC malfunctions. Can be prevented.

  In addition, out of the two switching elements of the inverter circuit having a flat outer shape and an insert type, the flat surface of the switching element located on the side edge in the longitudinal direction of the wiring board is substantially perpendicular to the side edge in the longitudinal direction. By being disposed, the discharge lamp lighting device is inclined during manufacture of the discharge lamp lighting device and does not protrude outward from the side edge. Therefore, the discharge lamp lighting device due to the occurrence of stress in the land of the switching element due to the contact between the lighting fixture and the switching element No early failure.

  In addition, the temperature of the smoothing capacitor is obtained by arranging the rectifying element and the smoothing capacitor of the rectifying circuit separately on the front and back of the wiring board and at positions where they do not overlap on the front and back of the board surface of the wiring board. Since the rise is suppressed, the shortening of the lifetime can be avoided.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 to 4 show an embodiment for carrying out the discharge lamp lighting device of the present invention. FIG. 1 is a circuit diagram, FIG. 2 is a front view and a rear view of a wiring board on which a lighting circuit is mounted, and FIG. FIG. 4 is a front view of the second inductor, and FIG. 4 is a side view of the second inductor showing the distribution direction of the leakage magnetic flux.

  In this embodiment, the discharge lamp lighting device is mounted on the wiring board 1, and includes an input terminal 2, a fuse 3, a high frequency cut filter 4, a rectifier circuit 5, a smoothing capacitor C2, an inverter circuit 6, a control IC 7, a load circuit 8, An output terminal 9 and a detection circuit 10 are provided to light the discharge lamp DL.

  The wiring board 1 has an elongated shape as a whole. As shown in the front view in FIG. 2A and the back view in FIG. Lands are formed in the chip-shaped parts.

  The input terminal 2 is disposed on the surface at one end side in the longitudinal direction of the wiring board 1. And it is comprised by a pair of terminal 2a, 2b connected to the low frequency alternating current power supply AC.

  The fuse 3 is inserted in series in the land of the unstable potential side line extending from the input terminal 2a.

  The high-frequency cut filter 4 is connected to the input terminal 2 and is disposed in the vicinity of the input terminal 2 in the longitudinal direction of the wiring board 1 and between the first inductor L1 inserted in series with the power supply line and the power supply line. A high frequency cut filter circuit is formed with the capacitor C1 connected in parallel to the capacitor C1, and a surge absorbing element SA is added in parallel with the capacitor C1. In this embodiment, a common mode choke is employed for the first inductor L1.

  The rectifier circuit 5 is a full-wave rectifier circuit composed of a diode bridge. The entire circuit is configured as a single chip-shaped component, is mounted on the back surface of the wiring board 1, is adjacent to the high-frequency cut filter 4, and is connected to the input terminal 2 via this.

  The smoothing capacitor C <b> 2 is an electrolytic capacitor and is connected between the DC output terminals of the rectifier circuit 4. Then, they are mounted on the front surface side of the wiring board 1 and arranged so as to be shifted from each other so as not to overlap with the rectifier circuit 5 in the direction perpendicular to the plate surface of the wiring substrate 1, that is, on the front and back of the plate surface. .

  The inverter circuit 6 is composed of a half-bridge type inverter including two switching elements Q1 and Q2 connected in series between both electrodes of the smoothing capacitor C2. The two switching elements Q1 and Q2 are each composed of an FET configured as an insert type having a flat plane. The switching element Q <b> 2 located on the side edge side of the wiring board 1 is arranged so that its flat plane is substantially orthogonal to the longitudinal direction of the wiring board 1. The switching element Q <b> 1 positioned relatively on the center side of the wiring board 1 is disposed such that the flat surface thereof is substantially parallel to the longitudinal direction of the wiring board 1.

  The control IC 7 is separated from the inverter circuit 6 and disposed on the back surface of the other end side of the wiring board 1 to control the inverter circuit 6. A resistor R and a capacitor C that perform a small signal operation are disposed around the control IC 7.

  In the load circuit 8, a second inductor L2, a resonant capacitor C3, a pair of DC cut capacitors C4 and C5, and a pair of filament capacitors C6 and C7 form a series circuit as shown in FIG. The inverter circuit 6 is connected in parallel to the switching element Q2. The load circuit 8, particularly the second inductor L 2, faces the output terminal 9, which will be described later, along the longitudinal direction of the wiring board 1, and the second inductor L 2 is the second inductor L 2 of the high-frequency cut filter 4. One inductor L1 is arranged adjacent to the wiring substrate 1 in the width direction.

  The second inductor L2 also serves as a ballast for the discharge lamp DL, and includes a core 11, a coil 12, and a pair of lead wires 13 as shown in FIG. The core 11 has, for example, a gap G in the center leg of the EE type. The coil 12 is wound around the central leg. The pair of lead wires 13 are mounted by being inserted into the wiring board 1 and soldered.

  Then, when a load current flows through the second inductor L2, leakage flux is distributed from the gap G to the outside in the front-rear direction, that is, the front and back directions of the second inductor L2 in FIG. In the side view shown in FIG. 4, the direction in which the leakage flux is distributed is indicated by arrows.

  In the present embodiment, the second inductor L2 is mounted such that the leakage magnetic flux is distributed along the longitudinal direction of the wiring board 1. Therefore, even if the first inductor L1 and the second inductor L2 of the high-frequency cut filter 4 are disposed substantially adjacent to each other in the board width direction, the leakage flux of the second inductor L2 is almost transferred to the first inductor L1. Therefore, the high frequency noise is hardly induced in the first inductor L1 of the high frequency cut filter 4 by magnetic coupling.

  The resonant capacitor C3 forms a resonant circuit with the second inductor L2. The discharge lamp DL is connected in parallel to the resonance capacitor C3 so that the resonance voltage generated in the resonance capacitor C3 is applied between the pair of electrodes.

  The DC cut capacitor C4 cuts off the instable potential side of the output end of the inverter circuit 6 and the load circuit 7 in a DC manner, and the DC cut capacitor C5 also cuts off the stable potential side and the load circuit 7 in a DC manner. Are inserted into the load circuit 8 in series.

  Filament capacitors C6 and C7 are connected in parallel between both ends of the filament electrode of the discharge lamp DL, and adjust the filament voltage applied to the filament electrode to a desired value. In this embodiment, the filament capacitors C6 and C7 are disposed using a space formed between the second inductor L2 and an output terminal 8 described later.

  The output terminal 9 is disposed on the surface adjacent to the input terminal 2 on one end side in the longitudinal direction of the wiring board 1, and two pairs of terminals 9a connected to both ends of a pair of filament electrodes of the discharge lamp DL, 9b, 9c and 9d.

  The detection circuit 10 is a circuit that detects the lamp voltage and half-wave discharge of the discharge lamp DL, and inputs the detection data to the control IC 7.

  The discharge lamp DL is a discharge lamp including a pair of filament electrodes such as a fluorescent lamp.

The circuit diagram which shows one form for implementing the discharge lamp lighting device of this invention Front and back views of a wiring board with a lighting circuit mounted Similarly, front view of the second inductor The side view of the 2nd inductor which also shows the distribution direction of leakage magnetic flux

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Wiring board, 2 ... Input terminal, 3 ... Fuse, 4 ... High frequency cut filter, 5 ... Rectifier circuit, 6 ... Inverter circuit, 7 ... Control IC, 8 ... Load circuit, 9 ... Output terminal, 10 ... Detection circuit, C2 ... smoothing capacitor, C3 ... resonance capacitor, C4, C5 ... DC cut capacitor, C6, C7 ... filament capacitor, DL ... discharge lamp, L1 ... first inductor, L2 ... second inductor, Q1, Q2 ... switching element

Claims (5)

Input terminal connected to low frequency AC power supply, high frequency cut filter including first inductor connected to input terminal, rectifier circuit connected to input terminal via high frequency cut filter, connected between DC output terminals of rectifier circuit An inverter circuit including a smoothing capacitor and a switching element and having a DC input terminal connected between both ends of the smoothing capacitor, a control IC for controlling the inverter circuit, a second inductor and a resonance circuit of the resonance capacitor, and connected to the AC output terminal of the inverter circuit And a lighting circuit with an output terminal for connecting the discharge lamp to the load circuit;
The lighting circuit is mounted, the input terminal and the output terminal are arranged on one end side in the longitudinal direction of the board, the high frequency cut filter is arranged in the vicinity of the input terminal, the load circuit is in the vicinity of the output terminal, and the board An elongate wiring substrate disposed in the vicinity of the high frequency cut filter in the width direction and disposed so that the leakage flux of the second inductor is distributed mainly in a direction parallel to the longitudinal direction of the substrate;
A discharge lamp lighting device comprising:   2. The discharge according to claim 1, wherein the control IC is disposed on the other end side in the longitudinal direction of the wiring board and on a surface opposite to the surface on which the input terminal and the output terminal are disposed. Lamp lighting device.   The inverter circuit includes two switching elements having a flat outer shape and an insert type, and a flat surface of the switching element located on the side edge in the longitudinal direction of the wiring board is disposed substantially orthogonal to the side edge in the longitudinal direction. The discharge lamp lighting device according to claim 1, wherein the discharge lamp lighting device is provided.   4. The rectifying device and the smoothing capacitor of the rectifying circuit are mounted separately on the front and back sides of the wiring board, and are disposed at positions where they are not overlapped on the front and back sides of the board surface of the wiring board. The discharge lamp lighting device according to any one of the above. A lighting fixture body;
A discharge lamp disposed in the luminaire body;
A discharge lamp lighting device according to any one of claims 1 to 4 for lighting the discharge lamp;
The lighting fixture characterized by comprising.

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