High voltage discharge lamp apparatus for vehicles

A discharge lamp apparatus having a DC power source and a discharge lamp comprising:

• a transformer for boosting a voltage of the power source;
• a switching element connected to a primary side of the transformer;
• and
• power control means for duty-controlling the switching element based on a signal indicating a lighting state of the discharge lamp to thereby control the power supplied to the discharge lamp;
• wherein the power control means is provided with power reduction means for reducing the power supplied to the discharge lamp as an apparatus temperature increases in addition to a power control for stabilizing a lighting of the lamp during a start-up period.

A discharge lamp apparatus having a DC power source and a discharge lamp comprising:

• a transformer for boosting a voltage of the power source;
• a switching element connected to a primary side of the transformer;
• and
• power control means for duty-controlling the switching element based on a signal indicating a lighting state of the discharge lamp to thereby control the power supplied to the discharge lamp,
• wherein the power control means is provided with power reduction means for reducing the power supplied to the discharge lamp as an apparatus temperature increases.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a DC—DC converter including a transformer for boosting a voltage supplied from the power source;
• a terminal connected electrically to the transformer;
• a hybrid IC having a circuit connected electrically to the terminal;
• a resin case to which the terminal is fixed and in which the transformer is contained;
• and
• an outer container for containing the transformer, the terminal, the hybrid IC, and the resin case, for applying a voltage based on the voltage boosted by the first transformer to the discharge lamp,
• wherein the hybrid IC is fixed on one face of the outer container in the outer container,
• wherein the transformer and the terminal are contained and fixed in the outer container together with the resin case, and
• wherein the transformer is disposed outside an outer periphery of the hybrid IC.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a DC—DC converter including a transformer for boosting a voltage supplied from the power source and a capacitor connected to the transformer in parallel;
• a filter inductor connected between the DC—DC converter and the power source for filtering noise generated from the DC—DC converter;
• a terminal connected electrically to the transformer, the capacitor, and the inductor;
• a hybrid IC having a circuit connected electrically to the terminal;
• a resin case to which the terminal is fixed and in which the transformer is contained;
• and
• an outer container for containing the first transformer, the inductor, the terminal, the hybrid IC, and the resin case, for applying a high voltage based on a voltage boosted by the first transformer to the discharge lamp,
• wherein the hybrid IC is fixed on one face of the outer container in the outer container,
• wherein the transformer, the inductor, and the terminal are contained and fixed in the outer container together with the resin case,
• wherein the first transformer, the capacitor, and the inductor are disposed outside an outer periphery of the hybrid IC, and
• wherein the capacitor is located between the first transformer and the inductor.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a DC—DC converter including a first transformer for boosting a voltage supplied from the power source;
• a second transformer for further boosting the voltage boosted by the DC—DC converter and for applying a high voltage to the discharge lamp;
• terminals connected electrically to the first transformer and the second transformer;
• a hybrid IC having a circuit connected electrically to the terminals;
• a resin case to which the terminals are fixed and in which the first transformer and the second transformer are contained;
• and
• an outer container for containing the first transformer, the second transformer, the terminal, the hybrid IC, and the resin case;
• wherein the hybrid IC is fixed on one face of the outer container in the outer container,
• wherein the first and second transformers and the terminal are contained and fixed in the outer container together with the resin case, and
• wherein the first transformer and the second transformer are disposed outside an outer periphery of the hybrid IC.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a DC—DC converter comprising a transformer for boosting a voltage supplied from the DC power source, a switching element connected to a primary winding of the transformer in series, and a capacitor connected in parallel with the transformer connected in series with the switching element, for generating the boosted voltage;
• a starter circuit having a thyristor for turning on the thyristor when the high voltage discharge lamp is started to light and for applying a high voltage pulse to the high voltage discharge lamp based on the boosted voltage generated from the DC—DC converter;
• and
• a gate circuit for generating the gate signal to turn on the thyristor,
• wherein the switching element and the gate circuit are both formed on a hybrid IC board,
• wherein the negative electrode side terminal of the capacitor is connected to a first wiring member and then connected to the hybrid IC board by way of the first terminal,
• wherein the cathode terminal of the thyristor is connected to a second wiring member and then connected to the hybrid IC board by way of the second terminal different from the first terminal, and
• wherein the first terminal and the second terminal are electrically connected on the hybrid IC board.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a DC—DC converter comprising a transformer for boosting a voltage supplied from the DC power source, a switching element connected to a primary winding of the transformer in series, and a capacitor connected in parallel to the transformer connected in series and the switching element, for generating the boosted voltage;
• a starter circuit having a thyristor for turning on the thyristor when a high voltage discharge lamp is started to light and for applying a high voltage pulse to the high voltage discharge lamp based on the boosted voltage generated from the DC—DC converter;
• and
• a gate circuit for generating a gate signal to turn on the thyristor,
• where in the switching element and the gate circuit are both formed on a hybrid IC board,
• wherein a n negative electrode terminal of the capacitor is connected to the hybrid IC board by way of a first terminal to thereby form electrical connection to the switching element, and
• a cathode terminal of the thyristor is connected to the hybrid IC board by way of a second terminal different from the first terminal to thereby form electrical connection to a portion to be connected to a ground formed on the hybrid IC board.

A discharge lamp apparatus having a DC power source and a high voltage discharge lamp comprising:

• a wiring member including a positive terminal to be connected to a positive terminal of the DC power source and a negative terminal to be connected to a negative electrode of the DC power source;
• a circuit functional section connected to the DC power source by way of the wiring member in series for applying a high voltage pulse to the high voltage discharge lamp based on the voltage that is obtained by boosting a voltage supplied from the DC power source to thereby light the high voltage discharge lamp;
• and
• a metal case for containing the wiring member and the circuit functional section,
• wherein a filter circuit is provided and includes an inductor connected to the circuit functional section in series between a positive electrode of the DC power source and the circuit functional section and a first capacitor connected between both ends of the positive terminal and the negative terminal so as to be connected in parallel to the circuit functional section connected in series and the inductor,
• wherein a portion of the negative terminal out of the wiring member is connected to the metal case, and
• the first capacitor is connected directly to the portion of the negative terminal out of the wiring member.

A discharge lamp apparatus having a DC power source and a discharge lamp comprising:

• a DC power source circuit for boosting a voltage of the DC power source by means of switching of a switching element and smoothing a boosted voltage by means of a smoothing capacitor;
• an H-bridge circuit for AC-lighting the discharge lamp by means of an output voltage of the DC power source circuit;
• and
• a starter circuit provided with a capacitor that is charged by means of an output voltage of the H-bridge circuit and a high voltage generation transformer having a primary winding connected to the capacitor and a secondary winding between the H-bridge circuit and the discharge lamp, the starter circuit being for boosting a charging voltage of the capacitor by means of the high voltage generation transformer when the discharge lamp is to be lighted and for applying the high voltage to the discharge lamp,
• wherein the discharge lamp is an vehicle 35W bulb, and
• wherein L2 (value at DC superimposition 1.5 A)≧2.5×10−3 (henry), capacitance C1≧0.5×10−6 (farad), and L2 (value at DC superimposition 0.4 A)×C1≧1×10−1×f−1.68 are satisfied, with L2 denoting an inductance of the secondary winding of the high voltage generation transformer, C1 denoting a capacitance of the smoothing capacitor, and f denoting a switching frequency of the switching element.

A discharge lamp apparatus comprising:

• an inverter circuit including a H-bridge circuit having four semiconductor switching elements having MOS structure disposed in a H-bridge configuration and bridge driving circuits having output terminals to be connected to the gate terminals of the semiconductor switching elements for driving the four semiconductor switching elements;
• and
• high voltage pulse generation means for applying a high voltage pulse to a discharge lamp to start lighting the discharge lamp, the high voltage pulse generation means being contained together with the inverter circuit in the same case,
• wherein the bridge driving circuits have four sets of two MOS transistors connected directly so as to correspond to the four semiconductor switching elements, respectively, and the four semiconductor switching elements are driven based on a potential of junction points of the two MOS transistors connected directly,
• wherein the output terminals of the bridge driving circuits are connected to gate terminals of the semiconductor switching elements of the H-bridge circuit by way of first resistors, and
• wherein, for at least any one set of the four sets of the MOS transistors connected directly of the bridge driving circuits, drains and sources of MOS transistors at a low side out of the elements connected directly are connected by way of first capacitors.

A discharge lamp apparatus comprising:

• an inverter circuit including a H-bridge circuit having four semiconductor switching elements having MOS structure disposed in a H-bridge configuration and bridge driving circuits for driving the four semiconductor switching elements;
• and
• high voltage pulse generation means for applying a high voltage pulse to a discharge lamp to start the lighting of the discharge lamp, the high voltage pulse generation means being contained together with the inverter circuit in the same case,
• wherein the bridge driving circuits have four driving circuits for driving the four semiconductor switching elements, respectively, output terminals of the four driving circuit are connected to gate terminals of the four semiconductor switching elements, respectively, and the four semiconductor switching elements are driven based on a potential difference between the output terminals and negative electrode side reference potential of the driving circuits, respectively,
• wherein the output terminals of the bridge driving circuits are connected to the gate terminals of the semiconductor switching elements of the H-bridge circuit by way of first resistors, and
• wherein, for at least any one of the four driving circuits, the output terminal is connected to a wiring provided as the negative electrode side reference potential by way of first capacitors.

A discharge lamp apparatus having a discharge lamp comprising:

• an inverter circuit including a H-bridge circuit having four semiconductor switching elements having MOS structure disposed in a H-bridge configuration and bridge driving circuits having output terminals to be connected to gate terminals of the semiconductor switching elements for driving the four semiconductor switching elements;
• and
• high voltage pulse generation means for applying a high voltage pulse to the discharge lamp to start lighting the discharge lamp, the high voltage pulse generation means being contained together with the inverter circuit in the same case,
• wherein the output terminals of the bridge driving circuits are connected to gate terminals of the semiconductor switching elements of the H-bridge circuit by way of first resistors, and
• a MOS capacitance value and a resistance value of the first resistors are set so that a time constant determined by the MOS capacitance value of the semiconductor switching elements having the MOS structure and the resistance value of the first resistors is at least 0.2 microsecond.

A discharge lamp apparatus comprising;

• an inverter circuit including a H-bridge circuit having four semiconductor switching elements having a MOS structure disposed in a H-bridge configuration and bridge driving circuits for driving the four semiconductor switching elements;
• and
• high voltage pulse generation means for applying a high voltage pulse to a discharge lamp to start lighting the discharge lamp, the high voltage pulse generation means being contained together with the inverter circuit in a same case,
• wherein the bridge driving circuits have four driving circuits for driving the four semiconductor switching elements, respectively, output terminals of the four driving circuit are connected to gate terminals of the four semiconductor switching elements, respectively, for two of the four driving circuit middle potential points of the H-bridge circuit are connected to terminals provided as a negative electrode side reference potential, for other two of the four driving circuits a ground potential point is connected to terminals provided as a negative electrode side reference potential, the four driving circuits drive the four semiconductor switching elements, respectively, based on a potential difference between the output terminals and the negative electrode side reference potential of the driving circuits, and
• on at least any one of the two bridge driving circuits having the terminals provided as the negative electrode side reference potential are connected to the middle potential points of the H-bridge circuit, the middle potential point of the H-bridge circuit is connected to the terminals provided as the negative electrode side reference potential by way of resistors, the middle points between the resistors and terminals provided as the negative electrode side reference potential are connected to the ground potential point by way of second capacitors.

A discharge lamp apparatus comprising:

• an inverter circuit including a H-bridge circuit having four IGBTs disposed in a H-bridge configuration and bridge driving circuits for driving the four IGBTs,
• wherein the bridge driving circuits have four driving circuits for driving the four IGBTS, respectively, output terminals of the four driving circuits are connected to gate terminals of the four IGBTS, respectively, and the four driving circuits drive the four IGBTs respectively based on a potential difference between the output terminals and negative electrode side reference potential of the driving circuits, and
• wherein, for two of the four driving circuits, middle potential points of the H-bridge circuit are connected to terminals provided as the negative electrode side reference potential, for other two of the four driving circuits a ground potential point is connected to terminals provided as the negative electrode side reference potential, and
• clamp means are connected to the terminal provided as the negative electrode side reference potential so that the terminal provided as the negative electrode side reference potential connected to the middle potential point of the H-bridge circuit in the bridge driving circuit is equalized to a predetermined voltage.

A discharge lamp apparatus comprising:

• an inverter circuit including a H-bridge circuit having four IGBTs disposed in a H-bridge configuration and bridge driving circuits for driving the four IGBTS,
• wherein the bridge driving circuits have four driving circuits for driving the four IGBTs, respectively, output terminals of the four driving circuit are connected to gate terminals of the four IGBTs, respectively, and the four driving circuits drive the four IGBTs respectively based on a potential difference between the output terminals and the negative electrode side reference potential of the driving circuits,
• wherein, for two of the four driving circuits middle potential points of the H-bridge circuit are connected to the terminals provided as a negative electrode side reference potential, for other two of the four driving circuits a ground potential point is connected to the terminals provided as a negative electrode side reference potential, and
• wherein, in the two bridge driving circuits in which the terminal provided as the negative electrode side reference potential is connected to a middle potential point of the H-bridge circuit, the middle potential point of the H-bridge circuit is connected to the terminal provided as the negative electrode side reference potential by way of resistors, and a middle point between the resistors and the terminal provided as the e negative electrode side reference potential is connected to the ground potential point by way of diodes.

A discharge lamp apparatus having a DC power source and a discharge lamp comprising:

• a DC—DC converter for boosting a voltage of the DC power source by a transformer;
• and
• an inverter circuit including a H-bridge circuit having four semiconductor switching elements disposed in a H-bridge configuration and bridge driving circuits for controlling on/off operation of the four semiconductor switching elements using the voltage boosted by the DC—DC converter as a voltage supply source, the voltage boosted by the DC—DC converter being converted to an AC voltage by the inverter circuit and the AC voltage being applied to the discharge lamp to AC-light the discharge lamp,
• wherein the voltage of the DC power source is applied to the DC—DC converter, on/off operation of the semiconductor switching elements is started after a predetermined time elapses from a time point when the DC—DC converter starts the operation, and the semiconductor switching elements are kept in off state before the predetermined time elapses.