JP2600433B2 - Discharge lamp lighting device - Google Patents
Discharge lamp lighting deviceInfo
- Publication number
- JP2600433B2 JP2600433B2 JP2102185A JP10218590A JP2600433B2 JP 2600433 B2 JP2600433 B2 JP 2600433B2 JP 2102185 A JP2102185 A JP 2102185A JP 10218590 A JP10218590 A JP 10218590A JP 2600433 B2 JP2600433 B2 JP 2600433B2
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- discharge lamp
- discharge lamps
- voltage
- lighting device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は高周波電圧発生回路を使用して複数個の放
電灯を点灯させる放電灯点灯装置に関する。Description: TECHNICAL FIELD The present invention relates to a discharge lamp lighting device for lighting a plurality of discharge lamps using a high-frequency voltage generation circuit.
［従来の技術］ 蛍光灯など放電灯を複数点灯し，調光することができ
る点灯装置として，例えば特開昭62−200685号公報に示
されたものがある。2. Description of the Related Art As a lighting device capable of lighting a plurality of discharge lamps such as a fluorescent lamp and adjusting the light, there is, for example, one disclosed in Japanese Patent Laid-Open No. 62-200685.
第４図はここに示された従来の放電灯点灯装置の回路
であり，同図において，（１）は直流電源，（２）は抵
抗，（３）はコンデンサ，（４），（５），（６）はそ
れぞれダイオード，（７）はトリガ素子，（８），
（９）はトランジスタからなるインバータのスイツチン
グ素子，（10），（11）は抵抗，（12）は駆動トラン
ス，（13）は結合コンデンサ，（14）は限流コイル，
（15）は共振コイル，（16）は負荷である放電灯，（1
7）は高周波電圧発生回路，（18）は予熱トランス，（1
9）は余熱用スイツチである。FIG. 4 is a circuit diagram of the conventional discharge lamp lighting device shown here, in which (1) is a DC power supply, (2) is a resistor, (3) is a capacitor, (4) and (5). , (6) are diodes, (7) is a trigger element, (8),
(9) is a switching element of an inverter composed of transistors, (10) and (11) are resistors, (12) is a driving transformer, (13) is a coupling capacitor, (14) is a current limiting coil,
(15) is a resonant coil, (16) is a discharge lamp as a load, (1)
7) is a high-frequency voltage generation circuit, (18) is a preheating transformer, (1)
9) is a switch for residual heat.
次に動作について説明する。 Next, the operation will be described.
トリガ素子（７）が導通しスイツチング素子（９）が
ONすると，スイツチング素子（８）をOFFし，トリガ素
子（７）に追従してスイツチング素子（８），（９）は
それぞれ交互にON−OFFし，高周波電圧を発生する。The trigger element (7) becomes conductive and the switching element (9) becomes
When turned on, the switching element (8) is turned off, and the switching elements (8) and (9) are alternately turned on and off following the trigger element (7) to generate a high-frequency voltage.
そして限流コイル（14）と共振コンデンサ（15）によ
つて共振的な電圧を発生するので，放電灯（16a），（1
6b）は放電を開始し，点灯する。Since a resonant voltage is generated by the current limiting coil (14) and the resonance capacitor (15), the discharge lamps (16a), (1)
6b) starts discharge and lights up.
この種の装置では放電灯（16a），（16b）は直列に接
続されているので，例えば高周波電圧発生回路（17）の
スイツチング素子（８），（９）の動作を変えて放電灯
（16a），（16b）の調光を行なうときは，双方の放電灯
（16a），（16b）は同一の調光度となる。また片方の放
電灯例えば（16a）が不点灯となれば必然的に他方の放
電灯（16b）も消灯することとなる。In this type of apparatus, since the discharge lamps (16a) and (16b) are connected in series, for example, the operation of the switching elements (8) and (9) of the high-frequency voltage generating circuit (17) is changed to change the discharge lamp (16a). ) And (16b), both discharge lamps (16a) and (16b) have the same dimming degree. When one of the discharge lamps, for example, (16a) is turned off, the other discharge lamp (16b) is necessarily turned off.
［発明が解決しようとする課題］ 従来の放電灯点灯装置は以上のように構成されていた
ので，負荷を全灯について調光するか，または消灯する
こととなり，一灯でも寿命などの異常で不点灯になる
と，全灯が不点灯になつてしまうという問題点があつ
た。[Problems to be Solved by the Invention] Since the conventional discharge lamp lighting device is configured as described above, the load is dimmed or turned off for all the lamps. When the lights were turned off, there was a problem that all the lights were turned off.
この発明は上記のような問題点を解決するためになさ
れたもので，複数の放電灯を共通の高周波電圧発生回路
で点灯しながら，一灯でも放電灯が異常になれば，これ
に対する電力の供給を個別に制限することができる放電
灯点灯装置を得ることを目的とする。The present invention has been made in order to solve the above-mentioned problems. When a plurality of discharge lamps are turned on by a common high-frequency voltage generating circuit, and even one of the discharge lamps becomes abnormal, the power consumption for the lamps is reduced. An object of the present invention is to provide a discharge lamp lighting device capable of individually restricting the supply.
［課題を解決するための手段］ この発明に係る放電灯点灯装置は，負荷である複数の
放電灯を並列に接続し高周波電圧を供給する高周波電圧
発生回路と，上記各放電灯と直列に接続されたそれぞれ
複数の結合コンデンサ，限流コイルおよびスイツチ回路
と，上記各放電灯と並列に接続された複数の共振コンデ
ンサと， 上記各放電灯の印加電圧を監視し，この電圧が所定値
を超えるときは異常指令を出す複数の保護回路と，この
保護回路の異常指令を受け，上記高周波電圧発生回路内
の制御信号と同期し，所定の時間遅延して上記各スイツ
チ回路を開く複数の開閉制御回路とを備えたものであ
る。また、上記スイッチ回路は等価的に逆並列接続とな
るダイオードを有するパワーMOS FETを含むものであ
る。[Means for Solving the Problems] A discharge lamp lighting device according to the present invention includes a plurality of discharge lamps, which are loads, connected in parallel and supplies a high frequency voltage, and a series connection with each of the discharge lamps. Monitoring the applied voltage of each of the plurality of coupled capacitors, current limiting coils, and switch circuits, the plurality of resonant capacitors connected in parallel with each of the discharge lamps, and each of the discharge lamps, and the voltage exceeding a predetermined value. A plurality of protection circuits for issuing an abnormality command, and a plurality of opening / closing controls for opening each of the switch circuits after a predetermined time delay in synchronism with a control signal in the high-frequency voltage generation circuit in response to the abnormality command of the protection circuit. And a circuit. Further, the switch circuit includes a power MOS FET having a diode which is equivalently anti-parallel connected.
［作用］ この発明においては，各放電灯の点灯状態が異常にな
ると放電灯の印加電圧が上昇するので，これを保護回路
で検出し，各放電灯と直列に接続されたスイツチ回路を
高周波電圧発生回路内の制御信号と同期し，所定の時間
遅延して開き電力の供給を個別に制限する。また、スイ
ッチ回路にパワーMOS FETの半導体スイッチを用いるの
で、高周波電圧発生回路の制御信号と同期してスイッチ
回路を開く。[Operation] In the present invention, when the lighting state of each discharge lamp becomes abnormal, the applied voltage of the discharge lamp rises. This is detected by the protection circuit, and the switch circuit connected in series with each discharge lamp is connected to the high-frequency voltage. In synchronization with the control signal in the generation circuit, the supply of the open power is individually restricted with a predetermined time delay. In addition, since a power MOS FET semiconductor switch is used for the switch circuit, the switch circuit is opened in synchronization with the control signal of the high frequency voltage generation circuit.
［発明の実施例］ 以下，この発明の実施例を図について説明する。An embodiment of the present invention will be described below with reference to the drawings.
従来技術と同一または相当部分は同一符号を付し，説
明を重複しない。The same or corresponding parts as those in the related art are denoted by the same reference numerals, and description thereof will not be repeated.
第一図はこの発明の放電灯点灯装置の一実施例を示す
回路図であり，図において，（13）は放電灯（16）と直
列に接続された結合コンデンサ，（14）は結合コンデン
サ（13）と共に放電灯（16）と直列に接続されたインダ
クタである限流コイル，（15）は放電灯（16）の非電源
側端子に接続され余熱電流を流す共振コンデンサ，（2
0）は放電灯（16）と直列に接続され電源の供給を開閉
するスイツチ回路で，ここではパワーMOS FETと，この
素子に内蔵したダイオード（21）により交流を流すこと
ができるものである。FIG. 1 is a circuit diagram showing an embodiment of a discharge lamp lighting device according to the present invention. In FIG. 1, (13) is a coupling capacitor connected in series with a discharge lamp (16), and (14) is a coupling capacitor ( A current-limiting coil, which is an inductor connected in series with the discharge lamp (16) together with 13), (15) is a resonant capacitor connected to the non-power supply side terminal of the discharge lamp (16), and through which residual heat current flows, (2)
Reference numeral 0) denotes a switch circuit connected in series with the discharge lamp (16) to open and close the supply of power. In this case, a power MOS FET and a diode (21) built in this element allow an alternating current to flow.
（22）は高周波電圧発生回路（17）のスイツチング素
子（８），（９）を高周波で交互にON/OFFさせる制御回
路であり，無安定マルチバイブレータなどの発信回路お
よびこの発信停止回路，スイツチング素子（８），
（９）をON/OFF駆動する駆動回路などからなる。(22) is a control circuit for alternately turning on / off the switching elements (8) and (9) of the high-frequency voltage generating circuit (17) at a high frequency. The transmitting circuit such as an astable multivibrator, the transmitting stop circuit, and the switching circuit. Element (8),
And (9) a drive circuit for ON / OFF driving.
（23）は抵抗（24），（25）からなる分圧器（26）に
より分圧して放電灯（16）の印加電圧を入力し，これを
基準電圧と比較し，この入力電圧が所定値を超えるとき
は異常として指令信号を発生する保護回路，（27）は保
護回路（23）の指令信号によりスイツチ回路（20）の開
閉を制御する開閉制御回路で，制御回路（22）の信号と
同期し，所定時間遅延してスイツチ回路（20）を開く遅
延回路を備えている。(23) is divided by a voltage divider (26) composed of resistors (24) and (25), and the voltage applied to the discharge lamp (16) is input. The input voltage is compared with a reference voltage. If it exceeds, a protection circuit that generates a command signal as an error. (27) is an open / close control circuit that controls the opening and closing of the switch circuit (20) by the command signal of the protection circuit (23), and is synchronized with the signal of the control circuit (22). And a delay circuit for opening the switch circuit (20) with a predetermined time delay.
以上のように，この実施例では，高周波電圧発生回路
（17）は複数の放電灯に共通であるのに対し，結合コン
デンサ（13），限流コイル（14），共振コンデンサ（1
5），スイツチ回路（20），保護回路（23），分圧器（2
6）および開閉制御回路（27）はそれぞれ各放電灯等に
備えられている。As described above, in this embodiment, the high-frequency voltage generation circuit (17) is common to a plurality of discharge lamps, whereas the coupling capacitor (13), the current limiting coil (14), and the resonance capacitor (1) are used.
5), switch circuit (20), protection circuit (23), voltage divider (2
6) and an open / close control circuit (27) are provided for each discharge lamp and the like.
次に動作について第２図および第３図のタイムチヤー
トを付加して説明する。Next, the operation will be described with reference to the time charts of FIGS. 2 and 3.
高周波電圧発生回路（17）の制御回路（22）がスイツ
チング素子（８），（９）を高周波で交互にON/OFFさせ
高周波電圧が発生しているとき，スイツチ回路（20）が
閉じている状態であれば，各放電灯（16）は点灯する。The control circuit (22) of the high-frequency voltage generating circuit (17) turns on and off the switching elements (8) and (9) alternately at high frequency, and when the high-frequency voltage is generated, the switch circuit (20) is closed. In the state, each discharge lamp (16) is turned on.
第２図はこの状態を示し，（Ａ），（Ｂ）はそれぞれ
スイツチング素子（８），（９）がON/OFFする信号を示
し，（Ｃ）はスイツチ回路（20）の動作を示し，（Ｄ）
は限流コイル（14）によりスイツチ回路（20）には遅れ
位相の電流が流れていることを示している。FIG. 2 shows this state, wherein (A) and (B) show signals for turning on / off the switching elements (8) and (9), respectively, and (C) shows the operation of the switching circuit (20). (D)
Indicates that a current having a lag phase flows through the switch circuit (20) by the current limiting coil (14).
従つて，スイツチ回路（20）を開くときは，同図
（Ｃ）（Ｄ）のように遅延時間ｔを考慮している。Therefore, when opening the switch circuit (20), the delay time t is taken into consideration as shown in FIGS.
第３図は複数の各放電灯（16）のうち少なくともいず
れかの１灯が異常状態となつたときを示す図で，図中V
CEはスイツチング素子（９）のコレクターエミツタ間の
電圧,ICは同コレクター電流,VLは放電灯（16）の両端に
印加されている電圧である。FIG. 3 is a view showing a case where at least one of the plurality of discharge lamps (16) is in an abnormal state.
CE is the voltage between the collector and the emitter of the switching element (9), I C is the collector current, and VL is the voltage applied to both ends of the discharge lamp (16).
例えば，放電灯（16a）のフイラメントが消耗し，た
ち消えを起こした状態を仮定すると，正常時は第３図
（ａ），（ｂ），（ｃ）のようなそれぞれスイツチング
素子（９）のコレクターエミツタ間電圧VCE,同コレクタ
ー電流IC,印加電圧VLとなつているものが，同図
（ｄ），（ｅ），（ｆ）のようになる。For example, assuming that the filament of the discharge lamp (16a) is exhausted and extinguished, in a normal state, the switching elements (9) shown in FIGS. 3 (a), (b) and (c) are used. The voltage between the collector and the emitter V CE , the same collector current I C , and the applied voltage V L are as shown in FIGS. 3 (d), (e) and (f).
これは異常時には高周波電圧発生回路（17）からは放
電灯（16a）を点灯させるため同図（ｅ）のような共振
状の大電流ICRが流れ，放電灯（16a）には同図（ｆ）の
ような高電圧VLRが印加される。In this case, when an abnormality occurs, the discharge lamp (16a) is turned on from the high-frequency voltage generation circuit (17), so that a resonant large current ICR flows as shown in FIG. A high voltage VLR as shown in f) is applied.
この高電圧は抵抗（24a），（25a）により分圧され印
加電圧VRとして保護回路（23a）に入力され,,基準電圧V
Oと比較される。This high voltage resistance (24a), is input to a protection circuit (23a) as a divided voltage applied V R by (25a) ,, reference voltage V
Compared to O.
この印加電圧VRが基準電圧VOを超えるときは保護回路
（23a）は指令信号Ｓを出力する。この指令信号Ｓは開
閉制御回路（27a）に送られ，開閉制御回路（27a）では
この信号を受け高周波電圧発生回路（17）の制御回路
（22）と同期し，所定時間遅延して位相を調整し，スイ
ツチ回路（20a）のパワーMOS FETを開き，放電灯（16
a）への高周波電力の供給を制限する。When the applied voltage V R exceeds the reference voltage V O , the protection circuit (23a) outputs a command signal S. This command signal S is sent to the switching control circuit (27a), which receives this signal and synchronizes it with the control circuit (22) of the high-frequency voltage generation circuit (17), delays the phase by a predetermined time, and shifts the phase. Adjust, open the power MOS FET of the switch circuit (20a), and set the discharge lamp (16
a) restrict the supply of high frequency power to
なお，上記印加電圧VRが基準電圧VOを大幅に超えると
きは，上記順序に従いスイツチ回路（20a）のパワーMOS
FETを開放状態として，放電灯（16a）への高周波電力
の供給を停止し，消灯させることもできる。When the applied voltage V R greatly exceeds the reference voltage V O , the power MOS of the switch circuit (20a) follows the above order.
With the FET open, the supply of high-frequency power to the discharge lamp (16a) can be stopped and turned off.
以上のように，この実施例では高周波電圧発生回路と
してインバータを用いたが，これに限定されず同期信号
が取り出せるものであればよい。As described above, although the inverter is used as the high-frequency voltage generation circuit in this embodiment, the invention is not limited to this, and any circuit that can extract a synchronization signal may be used.
また，スイツチ回路としてパワーMOS FETが適してい
るが，他の手段，例えばバイポーラトランジスタと逆並
列ダイアードなどでもよい。Although a power MOS FET is suitable as a switch circuit, other means such as a bipolar transistor and an antiparallel dyad may be used.
［発明の効果］ 以上のようにこの発明によれば，負荷である複数の放
電灯を並列に接続し高周波電圧を供給する高周波電圧発
生回路と，上記各放電灯と直列に接続されたそれぞれ複
数の結合コンデンサ，限流コイルおよびスイツチ回路
と，上記各放電灯と並列に接続された複数の共振コンデ
ンサと， 上記各放電灯の印加電圧を監視し，この電圧が所定値
を超えるときは異常指令を出す複数の保護回路と，この
保護回路の異常指令を受け，上記高周波電圧発生回路内
の制御信号と同期し，所定の時間遅延して上記各スイツ
チ回路を開く複数の開閉制御回路とを備えたので，複数
の放電灯を共通の高周波電圧発生回路で点灯しながら，
一灯でも放電灯が異常になれば，これに対する電力の供
給を個別に制限することができる放電灯点灯装置が得ら
れる効果がある。また、スイッチ回路に等価的に逆並列
接続となるダイオードを有するパワーMOS FETの半導体
スイッチを用いるので、高周波電圧発生回路の制御信号
と同期してスイッチ回路を開くことができる放電灯点灯
装置が得られる効果がある。[Effects of the Invention] As described above, according to the present invention, a plurality of discharge lamps, which are loads, are connected in parallel to supply a high-frequency voltage, and a plurality of discharge lamps connected in series with the respective discharge lamps are provided. Monitor the coupling capacitor, current-limiting coil, and switch circuit, the plurality of resonant capacitors connected in parallel with each of the discharge lamps, and the applied voltage to each of the discharge lamps. And a plurality of open / close control circuits that open the respective switch circuits after a predetermined time delay in synchronization with the control signal in the high-frequency voltage generating circuit upon receiving an abnormal command from the protective circuit. Therefore, while lighting multiple discharge lamps with a common high-frequency voltage generation circuit,
If even one of the discharge lamps becomes abnormal, there is an effect that a discharge lamp lighting device capable of individually restricting the supply of electric power thereto can be obtained. Also, since a power MOS FET semiconductor switch having a diode that is equivalently connected in anti-parallel is used for the switch circuit, a discharge lamp lighting device that can open the switch circuit in synchronization with the control signal of the high-frequency voltage generation circuit is obtained. Has the effect.
第１図はこの発明の放電灯点灯装置の一実施例を示す回
路図，第２図，第３図は同じく動作を示すタイムチヤー
ト，第４図は従来の放電灯点灯装置の回路図である。 図において，（１）は直流電源，（２）は抵抗，（３）
はコンデンサ，（４），（５），（６）はダイオード，
（７）はトリガ素子，（８），（９）はスイツチング素
子，（10），（11）は抵抗，（12）は駆動トランス，
（13）は結合コンデンサ，（14）は限流コイル，（15）
は共振コイル，（16）は放電灯，（17）は高周波電圧発
生回路，（18）は予熱トランス，（19）は予熱用スイツ
チ，（20）はスイツチ回路，（21）はダイオード，（2
2）は制御回路，（27）は開閉制御回路，（24），（2
5）は抵抗，（26）は分圧器，（23）は保護回路であ
る。 なお，図中，同一符号は同一または相当部分を示す。FIG. 1 is a circuit diagram showing an embodiment of the discharge lamp lighting device of the present invention, FIGS. 2 and 3 are time charts showing the same operation, and FIG. 4 is a circuit diagram of a conventional discharge lamp lighting device. . In the figure, (1) is a DC power supply, (2) is a resistor, and (3)
Is a capacitor, (4), (5) and (6) are diodes,
(7) is a trigger element, (8) and (9) are switching elements, (10) and (11) are resistors, (12) is a drive transformer,
(13) is a coupling capacitor, (14) is a current limiting coil, (15)
Is a resonant coil, (16) is a discharge lamp, (17) is a high-frequency voltage generation circuit, (18) is a preheating transformer, (19) is a switch for preheating, (20) is a switch circuit, (21) is a diode, (2)
2) is a control circuit, (27) is an open / close control circuit, (24), (2)
5) is a resistor, (26) is a voltage divider, and (23) is a protection circuit. In the drawings, the same reference numerals indicate the same or corresponding parts.
Claims (2)
周波電圧を供給する高周波電圧発生回路と、 上記各放電灯と直列に接続されたそれぞれ複数の結合コ
ンデンサ、限流コイルおよび上記高周波電圧発生回路と
同期して動作するスイッチ回路と、 上記各放電灯と並列に接続された複数の共振コンデンサ
と、 上記各放電灯の印加電圧を監視し、この電圧が所定値を
超えるときは異常指令を出す複数の保護回路と、 この保護回路の異常指令を受け、上記高周波電圧発生回
路内の制御信号と同期し、所定の時間遅延して上記各ス
イッチ回路を開く複数の開開制御回路とを備えたことを
特徴とする放電灯点灯装置。1. A high-frequency voltage generating circuit for connecting a plurality of discharge lamps serving as loads in parallel and supplying a high-frequency voltage, a plurality of coupling capacitors, a current-limiting coil, and a plurality of the respective high-frequency coils connected in series with the respective discharge lamps A switch circuit that operates in synchronization with the voltage generation circuit, a plurality of resonance capacitors connected in parallel with the discharge lamps, and monitors an applied voltage to each of the discharge lamps. If the voltage exceeds a predetermined value, an abnormality occurs. A plurality of protection circuits for issuing a command, a plurality of opening control circuits for receiving the abnormality command of the protection circuit, synchronizing with a control signal in the high-frequency voltage generation circuit, and opening each of the switch circuits with a predetermined time delay; A discharge lamp lighting device comprising:
なるダイオードを有するパワーMOS FETを含むことを特
徴とする特許請求の範囲（１）記載の放電灯点灯装置。2. The discharge lamp lighting device according to claim 1, wherein said switch circuit includes a power MOS FET having a diode which is equivalently antiparallel connected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2102185A JP2600433B2 (en) | 1990-04-18 | 1990-04-18 | Discharge lamp lighting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2102185A JP2600433B2 (en) | 1990-04-18 | 1990-04-18 | Discharge lamp lighting device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH042098A JPH042098A (en) | 1992-01-07 |
| JP2600433B2 true JP2600433B2 (en) | 1997-04-16 |
Family
ID=14320611
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2102185A Expired - Lifetime JP2600433B2 (en) | 1990-04-18 | 1990-04-18 | Discharge lamp lighting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2600433B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4955436B2 (en) * | 2007-03-26 | 2012-06-20 | フェニックス電機株式会社 | Light source device and exposure apparatus using the same |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61147740A (en) * | 1984-12-20 | 1986-07-05 | 三洋電機株式会社 | Power source circuit |
| JPS62199151A (en) * | 1986-02-27 | 1987-09-02 | Nec Corp | Line assignment system |
-
1990
- 1990-04-18 JP JP2102185A patent/JP2600433B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH042098A (en) | 1992-01-07 |
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