JP2006286451A - Discharge lamp lighting circuit, and discharge lamp lighting device, and light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting circuit wherein the potential of an auxiliary electrode (Et) during lighting of the lamp can be held at an intermediate potential between the potentials of both electrodes for main discharge without increasing excessive wiring, when the discharge lamp in which the auxiliary electrode other than the electrodes for main discharge is provided so as not to bring it into contact with a discharge space is lighted by ac, and the following problem is avoided: deviation is caused between both electrodes in the growth of the protrusions of the electrodes for main discharge. <P>SOLUTION: A trigger circuit for supplying a pulse current to the primary winding of a high voltage transformer having an autotransformer structure to impress a high voltage on the auxiliary electrode, a switch circuit for trigger feeding to feed the trigger circuit or to stop feeding, and a voltage dividing circuit for generating an intermediate voltage between voltages impressed on the electrodes for main discharge by dividing the voltage of the feeding circuit are provided, and the voltage dividing circuit is connected with the high voltage transformer. The switch circuit for trigger feeding feeds the trigger circuit when starting the discharge lamp, and stops feeding the trigger circuit after starting the discharge lamp. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting circuit for lighting a high-pressure mercury lamp, a discharge lamp lighting device configured using the discharge lamp lighting circuit, and a light source device configured using the discharge lamp lighting device.

For example, a high-intensity discharge lamp (HID lamp) is used in a light source device for an optical device for image display such as a liquid crystal projector or a DLP (TM) projector.
A light source device for this type of optical device is required to have a longer lamp life and a smaller discharge lamp lighting device.

When this type of lamp is lit, a high voltage is applied in a state where a voltage called a no-load open circuit voltage is applied to the lamp to cause a dielectric breakdown in the discharge space, and a glow discharge is caused to shift to an arc discharge.
As a method of applying a high voltage to the lamp, a method of superimposing a high voltage on an electrode for main discharge using an igniter, that is, in addition to the series trigger method, an auxiliary electrode other than the electrode for main discharge is provided in the discharge space. There is a method of applying a high voltage to the auxiliary electrode, that is, an external trigger method.
The external trigger system has various advantages over the serial trigger system as described in, for example, Japanese Patent Application Laid-Open No. 2002-270386 or Japanese Patent Application Laid-Open No. 2003-017283, and particularly feeds a high voltage generation unit including a high voltage transformer. When separated from the circuit unit and installed in the vicinity of the discharge lamp (Ld), the advantages can be enjoyed to the maximum. The advantage mentioned here is advantageous in reducing the size and weight of the discharge lamp lighting device, reducing noise, improving safety, and reducing costs.

However, as described in Japanese Patent Application Laid-Open No. 2004-039544, in a discharge space (Ls) surrounded by an envelope made of quartz glass, noble gas, 0.15 mg or more of mercury per cubic millimeter and 10 per cubic millimeter are used. A discharge lamp in which halogen of minus 6 square to minus square micromol is encapsulated and a pair of main discharge electrodes (E1, E2) are arranged opposite to each other with a distance of 2 mm or less in the discharge space is AC. In the case of lighting, if the conductor disposed on or near the outer surface of the lamp envelope is not maintained at a potential intermediate between the potentials of the electrodes for both main discharges, the main discharge for the main discharge It has been pointed out that there may be a problem that deviation occurs in both electrodes in the growth of the protrusions of the electrodes.
For this reason, in the aforementioned Japanese Patent Application Laid-Open No. 2004-039544, in the case of the external trigger method, as shown in FIG. 6, a high voltage transformer (Tz ′) for applying a high voltage to the auxiliary electrode (Et) is used. One end of the secondary winding (Hz ′) is connected to the middle of two capacitors (Cm1, Cm2) connected in parallel with the discharge lamp (Ld), and the potential of the auxiliary electrode (Et) during lamp lighting is Describes a technique for avoiding the problem of bias in both electrodes in the growth of the protruding portion of the electrode for the main discharge by maintaining the potential at an intermediate potential between the electrodes of the two electrodes for the main discharge. Has been.

However, when the technique shown in FIG. 6 is applied as an actual product as a high voltage generation unit including the high voltage transformer described above is separated from the power supply circuit unit and installed near the discharge lamp (Ld). Has problems in implementation and implementation.
FIG. 7 shows an example of a configuration when the technique shown in FIG. 6 is applied as an actual product. The function of the power feeding circuit (Ux), inverter (Ui), resistor (Rz), capacitor (Cz), and switch element (Qz) described in this figure is described in FIG. Basically the same as the thing.

As is apparent from this figure, in order to connect one end of the secondary winding (Hz ′) of the high voltage transformer (Tz ′) to the middle of the capacitors (Cm1, Cm2), a discharge lamp lighting circuit ( In the connector (CN1 ′) of Ub ′), an extra terminal (Tz3 ′) and extra cable wiring for connecting this to one end of the secondary winding (Hz ′) are required.
In the image display optical device described above, the discharge lamp lighting device is normally configured as a circuit that is not insulated from the commercial power supply line, from the viewpoint of reduction in size and weight and cost.
Therefore, since the terminal (Tz3 ′) and the wiring to the terminal become a primary circuit for the commercial power supply line as a dangerous voltage portion, the cable needs to be coated with a thickness having a predetermined dielectric strength. The contact of the connector (CN1 ′) requires a mechanical strength having a predetermined tensile strength. For this reason, the addition of a primary circuit wiring cable is a major obstacle to meet the demands for miniaturization and cost reduction required for optical devices, even if only one is required.

About the said capacitor | condenser (Cm1, Cm2), this is installed not in the said discharge lamp lighting circuit (Ub ') but in the vicinity of the said high voltage transformer (Tz'), The said terminal (Tz3 ') and wiring to this A configuration that eliminates the need for this is also conceivable. In this case, however, only the high-voltage transformer (Tz ′) is to be installed in the vicinity of the discharge lamp (Ld), but with the reliability required for the capacitors (Cm1, Cm2). Therefore, even if the connector uses the technology for holding the high voltage transformer (Tz ′) described in Japanese Patent Application Laid-Open No. 2003-017283, for example, a printed circuit board is required, This is a major obstacle to meet the demand for miniaturization and cost reduction required for optical devices.
In addition, components installed near the lamp must be installed in an environment that is overheated by the radiant heat of the lamp. However, in terms of safety standards, a transformer with type E heat resistance of 120 ° C is easily available. On the other hand, for example, a ceramic capacitor having a temperature of 85 ° C. is generally used, and there is a big problem that it is not easy to obtain a capacitor having higher heat resistance.
JP 2002-270386 JP 2003-017283 A JP2004039954A

  The problem to be solved by the present invention is that, when a discharge lamp provided with an auxiliary electrode (Et) other than an electrode for main discharge so as not to be in contact with the discharge space is AC-lit, an extra wiring is not increased. The potential of the auxiliary electrode (Et) during lamp operation can be maintained at a potential intermediate between the potentials of the two electrodes for main discharge, and in the growth of the protrusions of the electrode for main discharge An object of the present invention is to provide a discharge lamp lighting circuit, a discharge lamp lighting device, and a light source device that avoid the problem of occurrence of bias in both electrodes.

  The discharge lamp lighting circuit according to the first aspect of the present invention includes, in the discharge space (Ls), noble gas, 0.15 mg or more of mercury per cubic millimeter and 10 minus 6 to minus square micromoles per cubic millimeter. Halogen is enclosed, and a pair of main discharge electrodes (E1, E2) are disposed oppositely in the discharge space, and auxiliary electrodes (Et) other than the main discharge electrodes (E1, E2) are provided. A discharge lamp lighting circuit (Ub) for lighting a discharge lamp (Ld) provided so as not to contact the discharge space, a power feeding circuit (Ux) for feeding power to the discharge lamp (Ld), and the power feeding circuit An inverter (Ui) that is installed in a subsequent stage of (Ux) and reverses the polarity of the voltage applied to the discharge lamp (Ld), and an inverter for applying a high voltage to the auxiliary electrode (Et). A trigger circuit (Uz) for supplying a pulse current to the primary winding (Pz) of the high-voltage transformer (Tz) having a gate transformer structure, and a trigger power supply switch circuit (Uy) for supplying power to the trigger circuit (Uz) or stopping power supply ) And a voltage dividing circuit (Uv) for dividing the voltage of the power feeding circuit (Ux) to generate an intermediate voltage between the electrode (E1) and the voltage applied to the electrode (E2) for main discharge A terminal (Te1, Te2) for connecting the inverter (Ui) and the electrodes (E1, E2) for main discharge, the trigger circuit (Uz), the voltage dividing circuit (Uv), and the high voltage The trigger power supply switch circuit (Uy) has a terminal (Tz1, Tz2) for connecting to a voltage transformer (Tz), and the trigger power supply switch circuit (Uy) is configured to operate the trigger circuit (U ) The powers, after starting of the discharge lamp (Ld) is characterized in that the feed stop the trigger circuit (Uz).

  A discharge lamp lighting device according to claim 2 of the present invention is characterized in that the discharge lamp lighting circuit (Ub) according to claim 1 and the high-voltage transformer (Tz) are connected by a cable. is there.

  A light source device according to claim 3 of the present invention is characterized in that the discharge lamp lighting device (Up) according to claim 2 is connected to the discharge lamp (Ld).

  The light source device of claim 4 of the present invention is characterized in that, in the invention of claim 3, the high voltage transformer (Tz) and the discharge lamp (Ld) are configured as an integral unit (UL). It is.

  The discharge lamp lighting circuit, the discharge lamp lighting device, and the light source device according to the present invention are configured such that the potential of the auxiliary electrode (Et) during lamp lighting is changed between the electrodes of both electrodes for main discharge without increasing extra wiring. The potential can be maintained at an intermediate potential, and the problem of unevenness in both electrodes in the growth of the protruding portion of the electrode for main discharge can be avoided.

  First, the form for implementing this invention is demonstrated using FIG. 1 which is a block diagram which simplifies and shows one form of the discharge lamp lighting circuit of this invention. The power supply circuit (Ux) configured by a step-down chopper circuit or the like outputs a suitable voltage / current according to the state of the discharge lamp (Ld) or the lighting sequence. An inverter (Ui) composed of a full bridge circuit or the like converts the output voltage of the power feeding circuit (Ux) into, for example, a periodically inverted AC voltage and outputs it, and is connected via terminals (Te1, Te2). Applied to the pair of main discharge electrodes (E1, E2) of the discharge lamp (Ld).

  The high voltage transformer (Tz) has a so-called auto-transformer structure in which a primary winding (Pz) and a secondary winding (Hz) are connected inside or outside the high voltage transformer (Tz). And a high voltage boosted according to the turns ratio of the secondary winding to the primary winding and the voltage applied to the primary winding is generated in the secondary winding (Hz). , And can be applied to the auxiliary electrode (Et) of the discharge lamp (Ld) connected to one terminal of the secondary winding (Hz).

  The trigger circuit (Uz) is connected to the primary winding (Pz) of the high voltage transformer (Tz) via terminals (Tz1, Tz2), so that the trigger power supply switch circuit (Uy) is connected to the trigger circuit. When the power is fed to (Uz), the trigger circuit (Uz) can apply a voltage to the primary winding (Pz) to flow a pulse current, and conversely, the trigger feed switch circuit When (Uy) stops supplying power to the trigger circuit (Uz), the trigger circuit (Uz) does not perform an operation of flowing a pulse current through the primary winding (Pz).

  By the way, in FIG. 1, as shown by a broken line as an example, the trigger power supply switch circuit (Uy) includes a terminal (T11) and a terminal (T12) in which the trigger circuit (Uz) is an output of the power supply circuit (Ux). ) To receive power supply, or to be disconnected to stop power supply. However, the power supply source for the trigger circuit (Uz) is described with reference to the power supply circuit (Ux). ) Output is not necessary. For example, power may be received from a DC power supply (Mx) in the previous stage of the power supply circuit (Ux) described later.

The voltage dividing circuit (Uv) is a voltage applied to the electrodes (E1) and (E2) for main discharge by dividing the voltage of the power feeding circuit (Ux) by a voltage dividing element, for example, a voltage dividing resistor. Is generated at the terminal (Tz2).
As described above, the terminal (Tz2) is connected to the primary winding (Pz) of the high voltage transformer (Tz), and as described above, the high voltage transformer (Tz) is connected to the primary winding. The line (Pz) and the secondary winding (Hz) are connected. In the steady lighting state, the high voltage transformer (Tz) does not operate, so the secondary winding (Hz) Therefore, the auxiliary electrode (Et) of the discharge lamp (Ld) connected thereto is held at a voltage intermediate between the voltage (E1) for main discharge and the voltage applied to the electrode (E2). .

  As shown in FIG. 1, depending on the circuit configuration, the trigger power supply switch circuit (Uy) is connected in parallel to one voltage dividing resistor of the voltage dividing circuit (Uv). When the trigger power supply switch circuit (Uy) is supplying power to the trigger circuit (Uz), the voltage of the terminal (Tz2) is applied to the electrode (E1) and the electrode (E2) for main discharge. However, it is sufficient that this condition is generally satisfied during steady lighting.

  Further, in FIG. 1, a node to which the primary winding (Pz) and the secondary winding (Hz) of the high voltage transformer (Tz) are connected is connected to the terminal (Tz2). However, this may be connected to the terminal (Tz1). Which structure is to be used may be selected based on the waveform and polarity of the high voltage pulse applied to the auxiliary electrode (Et) when the high voltage transformer (Tz) is operated. Usually, it is advantageous to select one that increases the absolute value of the peak value of the voltage waveform of the high voltage pulse applied to the auxiliary electrode (Et).

  In the discharge lamp lighting circuit (Ub) configured as described above, one end of the secondary winding is held at a potential intermediate between the potentials of both electrodes for main discharge when connected to the high voltage transformer. For this reason, it is not necessary to provide extra wiring between the high voltage transformer and the discharge lamp lighting circuit, so the high voltage transformer (Tz) and the discharge lamp lighting circuit (Ub) are separated and connected by a cable. This is suitable for constituting a discharge lamp lighting device (Up). With this configuration, as described above, it is possible to enjoy advantages that are advantageous for reducing the size and weight of the discharge lamp lighting device, reducing noise, improving safety, reducing costs, and the like.

  In addition, in the discharge lamp lighting device (Up) configured using the discharge lamp lighting circuit (Ub) configured as described above, a highly heat-resistant one such as the capacitors (Cm1, Cm2) is available. Since it is not necessary to combine difficult parts with the high voltage transformer (Tz), the high voltage transformer (Tz) can be installed in the vicinity of the discharge lamp that is easily overheated by radiant heat. Therefore, when configuring the light source device, the high voltage transformer (Tz) and the discharge lamp (Ld) can be configured as an integrated unit (UL).

Next, a mode for carrying out the invention will be described with reference to an example drawing showing a more specific configuration.
FIG. 2 shows a simplified example of the power supply circuit (Ux) described in FIG. 1 or an embodiment described later, which is composed of a step-down chopper circuit. A power supply circuit (Ux) based on a step-down chopper circuit operates by receiving a voltage supplied from a DC power source (Mx) such as a PFC, and adjusts the amount of power supplied to the discharge lamp (Ld). In the power supply circuit (Ux), the current from the DC power source (Mx) is turned on / off by a switching element (Qx) such as an FET, and the smoothing capacitor (Cx) is charged via the choke coil (Lx). This voltage is applied to the discharge lamp (Ld) so that a current can flow through the discharge lamp (Ld).

  During the period when the switch element (Qx) is in the ON state, the current through the switch element (Qx) directly charges the smoothing capacitor (Cx) and supplies the current to the discharge lamp (Ld) as a load. In addition, energy is stored in the form of magnetic flux in the choke coil (Lx), and the flywheel diode is generated by the energy stored in the form of magnetic flux in the choke coil (Lx) while the switch element (Qx) is in the OFF state. Charging to the smoothing capacitor (Cx) and current supply to the discharge lamp (Ld) are performed via (Dx).

  In the step-down chopper type power supply circuit (Ux), power is supplied to the discharge lamp according to a ratio of a period during which the switch element (Qx) is in an on state, that is, a duty cycle ratio, to an operation cycle of the switch element (Qx). The amount can be adjusted. Here, a gate drive signal (Sg) having a certain duty cycle ratio is generated by the power supply control circuit (Fx), and the gate terminal of the switch element (Qx) is controlled via the gate drive circuit (Gx). The on / off of the current from the DC power source (Mx) is controlled.

  The lamp current flowing between the electrodes (E1, E2) of the discharge lamp (Ld) and the lamp voltage generated between the electrodes (E1, E2) are the lamp current detection means (Ix) and the lamp voltage detection means (Vx ) And can be detected. The lamp current detecting means (Ix) can be easily realized by using a shunt resistor, and the lamp voltage detecting means (Vx) can be easily realized by using a voltage dividing resistor.

  The lamp current detection signal (Si) from the lamp current detection means (Ix) and the lamp voltage detection signal (Sv) from the lamp voltage detection means (Vx) are input to the power supply control circuit (Fx). The power supply control circuit (Fx) outputs a voltage of about 300 V, which is typically called a no-load open voltage at the time of starting the lamp, and the voltage of the discharge lamp (Ld) is low immediately after starting the lamp. Since the rated power cannot be supplied, a constant current called an initial limiting current is output, and the voltage of the discharge lamp (Ld) increases as the temperature rises so that the rated power can be supplied. Depending on the voltage of the discharge lamp (Ld), the gate drive signal (Sg) is generated in a feedback manner so as to output a current having a value such that the power consumed by the discharge lamp (Ld) becomes the rated power. To do.

FIG. 3 is a diagram showing, in a simplified manner, one embodiment of a discharge lamp lighting circuit according to the present invention, which embodies the block diagram shown in FIG.
The inverter (Ui) is configured by a full bridge circuit using switching elements (Q1, Q2, Q3, Q4) such as FETs. Each switch element (Q1, Q2, Q3, Q4) is driven by a respective gate drive circuit (G1, G2, G3, G4), and the gate drive circuits (G1, G2, G3, G4) are diagonal. Control is performed by inverter control signals (Sf1, Sf2) generated by the inverter control circuit (Uf) so that the switch elements (Q1, Q3) and the switch elements (Q2, Q4) of the elements are turned on simultaneously.

  At the time of starting the lamp, when the switch element (Qy) such as FET or bipolar transistor constituting the trigger power supply switch circuit (Uy) is turned on, the resistance (Rz) and the high voltage transformer in the trigger circuit (Uz) The capacitor (Cz) is charged relatively slowly via the primary side winding (Pz) of (Tz) and the switch element (Qy). Therefore, the charging voltage of the capacitor (Cz) is generally applied to the switch element (Qz) using Sidac or the like as it is. When charging of the capacitor (Cz) proceeds and the voltage applied to the switch element (Qz) reaches a threshold voltage specific to the switch element (Qz), the switch element (Qz) rapidly enters a conductive state. Transition. Therefore, the capacitor (Cz) discharges rapidly through the switching element (Qz) and the primary winding (Pz) of the high voltage transformer (Tz), and the capacitor (Cz) A pulse current flows through the secondary winding (Pz).

  By this operation, as described above, a high voltage is generated in the secondary winding (Hz) of the high voltage transformer (Tz), and this high voltage is applied to the auxiliary electrode (Et) of the discharge lamp (Ld). The When the lamp starts and discharge starts at the electrodes (E1, E2) for main discharge, the switch element (Qy) is turned off. In addition, it can know that the discharge started by the said electrodes (E1, E2) by the said electric power feeding control circuit (Fx) detecting the fall of the said lamp voltage detection signal (Sv). The switch element (Qy) is controlled to be conductive / non-conductive through a gate drive circuit (Gy) by a trigger power supply switch control signal (Sy) from the power supply control circuit (Fx).

  The voltage dividing circuit (Uv) includes voltage dividing resistors (Rx1, Rx2). In the conductive state of the switch element (Qy), the voltage dividing resistor (Rx2) is short-circuited. However, when the discharge of the lamp is started, the switch element (Qy) is turned off. The short circuit is also released, and during the subsequent lamp operation, the auxiliary electrode (Et) of the discharge lamp (Ld) is connected to the voltage applied to the electrode (E1) and the electrode (E2) for main discharge. Held at an intermediate voltage.

  Although the description has been made here on the case where the voltage dividing resistor (Rx1, Rx2) is used as the voltage dividing element of the voltage dividing circuit (Uv), the current flowing through the voltage dividing element is not actively used. For example, an element that does not substantially flow a steady current can be used. As described above, when the voltage dividing resistor (Rx1, Rx2) is used as the voltage dividing element, it is preferable to set the resistance value from several hundreds of kilohms to several megaohms because it is easily available and the flowing current can be reduced.

  FIG. 4 is a simplified diagram showing another embodiment of the discharge lamp lighting circuit of the present invention. In the circuit of this figure, the trigger power supply switch circuit (Uy) is constituted by a Zener diode (Dy). In this case, since the Zener diode (Dy) is a passive element, a control signal corresponding to the trigger power supply switch control signal (Sy) as in the case of FIG. 3 is unnecessary.

Assuming that the voltage dividing resistors (Rx1, Rx2) of the voltage dividing circuit (Uv) are set to the same value and the voltage is divided in half, for example, if the lamp voltage upper limit value VLmax during steady lighting is set to 150 V, the Zener diode ( The Zener voltage Vznr of Dy) may be set to a voltage slightly higher than half of the lamp voltage upper limit value VLmax, for example, 80V.
Further, when the no-load open circuit voltage VLopn generated by the power supply circuit (Ux) at the time of start is 300 V, for example, the output voltage of the voltage dividing circuit (Uv), that is, the voltage divided by the voltage dividing resistors (Rx1, Rx2) is 150 V. Since the Zener diode (Dy) has a Zener voltage higher than 80V, a Zener current flows to the Zener diode (Dy) through the voltage dividing resistor (Rx1), and the Zener diode (Dy) A Zener voltage of 80V is generated.
Therefore, the capacitor 220 (Cz) in the trigger circuit (Uz) is applied with a maximum 220 V difference between the no-load open-circuit voltage VLopn and the Zener voltage Vznr, and the switch element (Qz) using Sidac or the like. Since only this voltage can be applied, the threshold voltage of the switch element (Qz) may be set to 200V, for example.

By configuring in this way, the discharge lamp lighting circuit shown in FIG. 4 has the trigger power supply switch that has been in a non-conductive state when the power supply circuit (Ux) generates a no-load open voltage VLopn at the time of starting. When a current flows through the circuit (Uy), power supply to the trigger circuit (Uz) is started, and charging of the capacitor (Cz) is started.
When the capacitor (Cz) is charged up to the threshold voltage of the switch element (Qz), the switch element (Qz) shifts to a conductive state, and the primary side winding ( Pz) is rapidly discharged, so that a pulse current flows through the primary winding (Pz) of the high voltage transformer (Tz), and a high voltage is applied to the auxiliary electrode (Et) of the discharge lamp (Ld). Is applied.

  As a result, when the lamp is started and discharge starts at the electrodes (E1, E2) for main discharge, the lamp voltage, that is, the output voltage of the feeder circuit (Ux) is the arc discharge voltage, and the typical initial voltage is As long as the voltage drops rapidly to about 10 V and the lamp voltage is below the lamp voltage upper limit value VLmax, the output voltage of the voltage dividing circuit (Uv) never reaches the threshold voltage of the switch element (Qz). Therefore, the switch element (Qz), that is, the trigger power supply switch circuit (Uy) is maintained in a non-conductive state, and the trigger circuit (Uz) is maintained in a power supply stop state.

  The discharge lamp lighting circuit in FIG. 3 actively controls the trigger power supply switch circuit (Uy) by the trigger power supply switch control signal (Sy) to control power supply to the trigger circuit (Uz) and power supply stop. In this way, it can be configured to passively perform an intended operation without using a special trigger feed switch control signal (Sy).

  In the discharge lamp lighting circuit of FIG. 3, capacitors (Cv1, Cv2) similar to the capacitors (Cm1, Cm2) shown in FIG. 6 are installed, but these mainly use the potential of the auxiliary electrode (Et). It is not for holding at a potential intermediate between the potentials of the electrodes for discharging, but when the high voltage transformer (Tz) is activated, a high voltage is applied to the auxiliary electrode (Et), and the discharge space When the dielectric barrier discharge occurs in (Ls) and the discharge space (Ls) becomes conductive, the electrodes (E1, E2) are exposed to a high voltage, and this voltage constitutes the inverter (Ui). This is to protect the switch elements (Q1, Q2, Q3, Q4) from the danger of destruction. Specific examples of the capacitance values of the capacitors (Cv1, Cv2) include several tens of values as the current that flows when the polarity of the inverter (Ui) is reversed is not excessive and the effect of protecting against the above-described danger can be exhibited. It is preferable to set from picofarad to several hundred picofarads.

  However, if any of the switch elements (Q1, Q3) of the diagonal elements and any of the switch elements (Q2, Q4) are in a conductive state, these switch elements (Q1, Q2, Q3, Q4) Will not be destroyed. Capacitance of the switch elements (Q1, Q2, Q3, Q4) even when both of the switch elements (Q1, Q3) of the diagonal elements or both of the switch elements (Q2, Q4) are non-conductive. (If these switch elements are FETs, there is a capacitance between the source and the drain), it is usually not necessary to install the capacitors (Cv1, Cv2).

Regarding the above-mentioned lamp voltage upper limit value VLmax, since the steady state lamp voltage becomes such a high value when the life of the lamp is exhausted, the above-described power supply control circuit (Fx) is in the steady state. When the lamp voltage is monitored and it is detected that the lamp voltage exceeds the upper limit VLmax, the lamp is controlled to be turned off.
Accordingly, the lamp is lit in a state where the lamp voltage in the steady state exceeds the lamp voltage upper limit value VLmax, the Zener diode (Dy) is turned on at an undesired time, and the high voltage transformer (Tz) is activated. Usually does not occur.

  FIG. 5 is a simplified diagram showing another embodiment of the discharge lamp lighting circuit according to the present invention. This discharge lamp lighting circuit is applied to the electrodes (E1, E2) for main discharge when the high-voltage transformer (Tz) is operated, as compared with FIGS. A device for improving the lighting performance of the discharge lamp (Ld) is provided by adding a transformer (Th) for increasing the voltage.

  A capacitor (Ch) is added to the trigger circuit (Uz), and is connected to a connection node between the resistor (Rz) and the switch element (Qz) together with the capacitor (Cz), and the primary winding of the transformer (Th) The capacitor (Ch) is charged via the line (Ph). Therefore, when a pulse current flows through the primary side winding (Pz) of the high voltage transformer (Tz) and a high voltage pulse is applied to the auxiliary electrode (Et), the primary of the transformer (Th) is similarly applied. A pulse current flows in the side winding (Ph), a voltage is generated in the secondary side winding (Sh), and is superimposed on the no-load open voltage applied to the electrodes (E1, E2) from the power supply circuit (Ux). Is done.

  As a result, the lighting performance of the discharge lamp (Ld) is improved. For the transformer (Th), the voltage waveform generated in the secondary winding (Sh) is such that the high voltage pulse applied to the auxiliary electrode (Et) and a suitable timing and polarity are used. What is necessary is just to set the inductance value and winding direction of a primary side winding (Ph) and the said secondary side winding (Sh).

  Since the transformer (Th) is provided downstream from the inverter (Ui), if the polarity inversion phase of the inverter (Ui) and the operation timing of the transformer (Th) are uncontrolled, the transformer (Th If the voltage generated by the secondary winding (Sh) of Th) is superimposed, the absolute value of the voltage applied to the electrodes (E1, E2) may be lowered. . Therefore, the polarity of the inverter (Ui) is reversed so that the transformer (Th) operates at the timing when the absolute value of the voltage applied to the electrodes (E1, E2) is increased. At the time of start-up, the polarity inversion operation of the inverter (Ui) is stopped under conditions suitable for the polarity of the voltage generated by the secondary winding (Sh) of the transformer (Th). It is desirable to make it.

  The circuit configuration described in this specification describes the minimum necessary components for explaining the operation, function, and operation of the discharge lamp lighting circuit and the discharge lamp lighting device of the present invention. Therefore, the details of the circuit configuration and operation described, such as signal polarity, selection, addition, omission of specific circuit elements, or ingenuity such as changes based on the convenience of obtaining elements and economic reasons Is assumed to be performed at the time of designing the actual device.

  In particular, a mechanism for protecting circuit elements such as FETs and other switch elements from damage factors such as overvoltage, overcurrent, and overheating, or generation of radiation noise and conduction noise generated by the operation of circuit elements of the power feeding device Mechanisms to reduce or prevent generated noise, such as snubber circuit, varistor, clamp diode, current limit circuit (including pulse-by-pulse method), common mode or normal mode noise filter choke coil, noise It is assumed that a filter capacitor or the like is added to each part of the circuit configuration described in the embodiment as necessary.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which simplifies and shows the discharge lamp lighting circuit of this invention, a discharge lamp lighting device, and a light source device is represented. 2 shows a simplified configuration of a part of an embodiment of a discharge lamp lighting circuit, a discharge lamp lighting device, and a light source device according to the present invention. 1 shows a simplified configuration of an embodiment of a discharge lamp lighting circuit, a discharge lamp lighting device, and a light source device according to the present invention. 1 shows a simplified configuration of an embodiment of a discharge lamp lighting circuit, a discharge lamp lighting device, and a light source device according to the present invention. 1 shows a simplified configuration of an embodiment of a discharge lamp lighting circuit, a discharge lamp lighting device, and a light source device according to the present invention. The principle figure of the conventional super-high pressure mercury lamp apparatus is represented. 7 represents a simplified configuration of a possible implementation of the ultra-high pressure mercury lamp apparatus of FIG.

Explanation of symbols

CN1 Connector CN1 ′ Connector Ch Capacitor Cm1 Capacitor Cm2 Capacitor Cv1 Capacitor Cv2 Capacitor Cx Smoothing Capacitor Cz Capacitor Dx Flywheel Diode Dy Zener Diode E1 Electrode E2 Electrode Et Auxiliary Electrode Fx Feed Control Circuit G1 Gate Drive Circuit G2 Gate Drive Circuit G3 Gate Drive Circuit G4 Gate drive circuit Gx Gate drive circuit Gy Gate drive circuit Hz Secondary side winding Hz 'Secondary side winding Ix Lamp current detection means Ld Discharge lamp Ls Discharge space Lx Choke coil Mx DC power supply Ph Primary side winding Pz 1 Secondary winding Pz 'Primary winding Q1 Switch element Q2 Switch element Q3 Switch element Q4 Switch element Qx Switch element Qy Switch element Qz Switch element Rx1 Voltage dividing resistor Rx2 Voltage dividing resistor Rz Resistance S 1 Inverter control signal Sf2 Inverter control signal Sg Gate drive signal Sh Secondary winding Si Lamp current detection signal Sv Lamp voltage detection signal Sy Trigger feed switch control signal T01 terminal T02 terminal T11 terminal T12 terminal T21 terminal T22 terminal T31 terminal T32 terminal Te1 terminal Te1 'terminal Te2 terminal Te2' terminal Th transformer Tz high voltage transformer Tz 'high voltage transformer Tz1 terminal Tz1' terminal Tz2 terminal Tz2 'terminal Tz3' terminal UL unit Ub discharge lamp lighting circuit Ub 'discharge lamp lighting circuit Uf inverter control Circuit Ui Inverter Ui 'Inverter Up Discharge lamp lighting device Uv Voltage dividing circuit Ux Power supply circuit Uy Trigger power supply switch circuit Uz Trigger circuit Vx Lamp voltage detection means

Claims (4)

In the discharge space (Ls), rare gas, 0.15 mg or more of mercury per cubic millimeter and 10 minus 6 to minus square micromol of halogen per cubic millimeter are enclosed, and a pair of main components are contained in the discharge space. Discharge lamps (E1) and (E2) for discharge are arranged opposite to each other, and auxiliary electrodes (Et) other than the electrodes (E1, E2) for main discharge are provided so as not to contact the discharge space ( A discharge lamp lighting circuit (Ub) for lighting Ld),
A power supply circuit (Ux) that supplies power to the discharge lamp (Ld); an inverter (Ui) that is installed at a subsequent stage of the power supply circuit (Ux) and reverses the polarity of a voltage applied to the discharge lamp (Ld); A trigger circuit (Uz) for supplying a pulse current to a primary winding (Pz) of a high voltage transformer (Tz) having an autotransformer structure for applying a high voltage to the electrode (Et), and the trigger circuit (Uz) ) And a voltage applied to the electrode (E1) and the electrode (E2) for main discharge by dividing the voltage of the power supply circuit (Ux). A voltage dividing circuit (Uv) for generating an intermediate voltage, terminals (Te1, Te2) for connecting the inverter (Ui) and the electrodes (E1, E2) for main discharge, and the trigger circuit (Uz) and has a voltage dividing circuit (Uv) and the high-voltage transformer terminals for connecting (Tz) and the (Tz1, Tz2),
The trigger power supply switch circuit (Uy) supplies power to the trigger circuit (Uz) when starting the discharge lamp (Ld), and supplies power to the trigger circuit (Uz) after starting the discharge lamp (Ld). Discharge lamp lighting circuit characterized by stopping.   A discharge lamp lighting device comprising the discharge lamp lighting circuit (Ub) according to claim 1 and the high voltage transformer (Tz) connected by a cable.   The light source device according to claim 2, wherein the discharge lamp lighting device (Up) according to claim 2 is connected to the discharge lamp (Ld). The light source device according to claim 3, wherein the high-voltage transformer (Tz) and the discharge lamp (Ld) are configured as an integrated unit (UL).

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