JP2006093009A - High pressure discharge lamp lighting device and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp lighting device capable of obtaining a substantially constant dimming illuminance for almost the whole period of service life from the start to the end of the service life for using an illuminance sensor, an accumulating timer, etc. <P>SOLUTION: In the high pressure discharge lamp lighting device for lighting a discharge lamp by supplying AC power to a high pressure discharge lamp, first output power W1 is outputted at a first output voltage V1, and second output power W2 larger than the first output power W1 is outputted at a second output voltage V2 larger than the first output voltage V1. The first output voltage V1 is a voltage value of the discharge lamp when the high pressure discharge lamp is in an early stage of the service life, and the second output voltage V2 is a voltage value of the discharge lamp when the high pressure discharge lamp is in an end stage of the service life. The first output power W1 is set smaller than the rated power of the high pressure discharge lamp. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high pressure discharge lamp lighting device and a lighting device using the same.

  FIG. 24 is a block diagram of a lighting device disclosed in Japanese Patent Laid-Open No. 11-1851973 (Patent Document 1). The lamp L, the illuminance sensor S that detects reflected light from the desk surface and outputs a voltage proportional to the amount of reflected light, the control unit 20 that changes the dimming signal according to the detection value of the illuminance sensor S, and the control unit 20 And a dimming ballast 10 that controls the light output of the lamp L in response to the dimming signal from the lamp L. In this configuration, the desk top illuminance can be made substantially constant by feedback controlling the light output of the lamp L so that the detection output of the illuminance sensor S becomes a set reference value.

In general, even when the lamp is always lit in the rated lighting state, the light output of the lamp gradually decreases due to the deterioration of the luminous flux due to the change over time. Therefore, if the light output controlled to be substantially constant is set to a dimming state (for example, a level that is reduced by 30% from the initial value) from the beginning, a constant light output can be obtained until near the lamp life.
Japanese Patent Laid-Open No. 11-185773

  In the technique disclosed in Patent Document 1, although the light output can be made substantially constant, an illuminance sensor is required, which increases the size of the apparatus, complicates the control, or increases the cost. Therefore, it is conceivable to maintain the illuminance approximately constant by changing the light output according to the time by using an integration timer or the like that calculates the lighting time without using the illuminance sensor as in Patent Document 1.

  FIG. 25 shows the change in illuminance with respect to the elapsed time of lighting, and (a) shows the change in illuminance when the lamp is always lit with rated lighting. As time goes on, the illuminance gradually decreases. In the figure, t1 indicates a time corresponding to the end of life.

  FIG. 26 shows a change in the power consumption of the lamp with respect to the elapsed lighting time. Like FIG. 25, (a) shows the power consumption when the lamp is lit at the rated lighting. Indicates the time corresponding to the end of life.

  Here, the illuminance is as shown in FIG. 25B by changing the power supplied to the lamp so as to have the characteristics of FIG. Therefore, a substantially constant brightness can be obtained with the illuminance S1. Accordingly, the shaded area in FIG. 25C corresponds to “extra brightness” for lighting at a substantially constant illuminance or higher, and the shaded area in FIG. Is equivalent to "energy". In the case of Patent Document 1, if the light output detected by the illuminance sensor is set to the illuminance S1, substantially the same characteristics as shown in FIG. 25B can be obtained.

  However, instead of the illuminance sensor, an integration timer is required, and it is necessary to reset the integration timer when replacing the lamp. Therefore, when the usage method becomes complicated or the reset is performed automatically Since a control circuit for that purpose is further required, this also causes an increase in the size and cost of the apparatus.

  The present invention has been made in view of such circumstances, and its object is to use almost the entire life cycle from the beginning of life to the end of life without using an illuminance sensor or an integration timer. An object of the present invention is to provide a high pressure discharge lamp lighting device capable of obtaining a substantially constant dimming intensity.

  According to the high pressure discharge lamp lighting device of the present invention, in order to solve the above-mentioned problem, in the high pressure discharge lamp lighting device for lighting the discharge lamp by supplying AC power to the high pressure discharge lamp, as shown in FIG. In addition, the first output power W1 is output at the first output voltage V1, and the second output voltage V2 greater than the first output voltage V1 is greater than the first output power W1. The first output voltage V1 is the voltage value of the discharge lamp at the initial stage of the life of the high pressure discharge lamp, and the second output voltage V2 is the life of the high pressure discharge lamp. It is a voltage value of the discharge lamp at the end, and the first output power W1 is smaller than the rated power of the high-pressure discharge lamp.

According to the first to third aspects of the invention, a substantially constant illuminance can be obtained from the beginning to the end of the life of the discharge lamp, and there is no need to use an illuminance sensor or an integration timer. Even when a plurality of discharge lamps are lit by a plurality of lighting devices and discharge lamps at the beginning or end of life are mixed, there is little variation in illuminance and uniform illuminance can be obtained.
According to the invention of claim 4 or 5, a constant illuminance can be obtained by detecting the discharge lamp voltage and controlling the DC / DC converting means or the switching element of the DC power supply, and the discharge lamp voltage can be detected by starting control or Can also be used for other controls such as abnormality protection. In addition, a circuit for making the illuminance constant can be easily configured.
According to the invention of claim 6, the mode of rated lighting and dimming lighting can be switched, and it can be used as a discharge lamp lighting device of rated lighting, and the application range is expanded. In addition, even after installation of the appliance, switching between rated lighting and dimming lighting with a constant illuminance can be easily performed.

According to the invention of claim 7, it is possible to easily distinguish between the rated lighting mode and the dimming mode. In addition, since the same starting characteristics as the rated lighting are sufficient, the design becomes easy.
According to the invention of claim 8, since the illuminance does not change from the rated lighting to the dimming lighting, it is possible to shift to the dimming lighting without changing the atmosphere after starting. Moreover, at the time of a slow leak, a dimming lighting state can be maintained and a discharge lamp can be protected.
According to the ninth aspect of the present invention, the same starting characteristics as the rated lighting are sufficient, and therefore the design is facilitated.
According to the invention of claim 10, excessive power supply to the discharge lamp can be prevented. Further, when the discharge lamp voltage becomes high, the user can easily recognize that the discharge lamp is at the end of its life.

According to the eleventh aspect of the invention, an illuminance equivalent to that at the end of the life of rated lighting can be obtained.
According to the twelfth aspect of the present invention, a constant illuminance of, for example, about 75% or less with respect to the illuminance of rated lighting can be obtained at the beginning and end of the lifetime.
According to the invention of claim 13, the dimming illuminance of the lighting device can be made constant without using an illuminance sensor or an integration timer.

(Embodiment 1)
FIG. 1 shows output characteristics of the high pressure discharge lamp lighting device according to Embodiment 1 of the present invention. The graph of FIG. 1 shows the output characteristic of the high-pressure discharge lamp lighting device, that is, the characteristic of the output power with respect to the output voltage. The first output voltage V1 is the first output power W1, and the second At the output voltage V2, the discharge lamp is lit with the second output power W2. That is, the output characteristic passes through two points (V1, W1) and (V2, W2).

  In the case of a high-pressure discharge lamp, generally, when the lamp is continuously lit with the same power, the value of the discharge lamp voltage at the end of the life increases compared to the discharge lamp voltage at the beginning of lighting. Therefore, in FIG. 1, the first output voltage V1 is set to the discharge lamp voltage at the beginning of the life of the discharge lamp, the second output voltage V2 is set to the discharge lamp voltage at the end of the life of the discharge lamp, and the second When the discharge lamp is lit with this lighting device by setting the output power W2 of the discharge lamp to the rated power of the discharge lamp and the first output power W1 to an arbitrary dimming power, the dimming power is used at the beginning of the life of the discharge lamp. It will be lit and will be lit at the rated power at the end of the life of the discharge lamp.

  As described in the conventional example, when the rated lighting is always performed, the light output of the lamp gradually decreases as shown in FIG. Therefore, as shown in FIG. 2, by setting the illuminance ratio at the beginning of the life to D1 which is about the same as the illuminance ratio at the end of the life, it is possible to maintain the same illuminance ratio at the end of the life of the discharge lamp. . Here, the illuminance ratio represents the ratio of the illuminance during dimming lighting to the illuminance during rated lighting. In all of the embodiments to be described below, “dimming” means lighting with power smaller than rated lighting unless otherwise specified.

  If the output characteristics of the discharge lamp lighting device are set so as to pass two points as shown in FIG. 1, almost the same illuminance can be obtained at the beginning and end of the life of the discharge lamp as shown in FIG. In other words, an illuminance equivalent to that at the end of the life of the rated lighting can be obtained. Further, it is not necessary to use the illuminance sensor or the integration timer described in the conventional example.

  In the case of a high-pressure discharge lamp, since the lifetime due to light beam deterioration is about 30 (%) decreased from the initial illuminance at the end of the lifetime, the dimming power W1 is about 75 (%) in consideration of variations and the like. The following illuminance ratio is desirable. This is because when the illuminance ratio is set higher than 75 (%) at the first output voltage V1, the luminous flux deteriorates to about 70 (%) with the passage of time even if it is originally rated lighting. Therefore, the illuminance set by the first output voltage V1 cannot be maintained at the second output voltage V2. By setting the dimming power W1 to an illuminance ratio of about 75 (%) or less, a constant illuminance of about 75 (%) or less with respect to the illuminance of the rated lighting can be obtained at the beginning and end of the life.

  FIG. 3 is an example specifically showing the configuration of the high-pressure discharge lamp lighting device according to the present invention. In the block configuration diagram of the conventional example shown in FIG. 24, the illuminance sensor S is omitted. However, the lamp L in FIG. 24 is a high-pressure discharge lamp DL, and the portion corresponding to the dimming ballast 10 in FIG. 24 includes a DC power source 11, a DC-DC conversion means (DC / DC conversion means) 12, and This is an example constituted by a DC-AC conversion hand throw (DC / AC conversion means) 13.

  The DC power supply 11 includes an AC power supply Vs, a diode bridge DB including diodes D1, D2, D3, and D4, and a step-up chopper circuit including an inductor L1, a switching element Q1, a diode D5, and an electrolytic capacitor C1.

  The DC / DC converting means 12 is a step-down chopper circuit composed of a switching element Q2, a diode D6, an inductor L2, and a capacitor C2, and a resistor R0 for detecting a lamp current is connected in series to the ground side of the output end of the step-down chopper circuit. Has been inserted. By adjusting the on / off state of the switching element Q2, the value of the lamp power supplied to the high-pressure discharge lamp DL by the DC / AC conversion means 13 at the subsequent stage can be controlled.

  In the DC / AC conversion means 13, a series circuit of switching elements Q3 and Q4 and a series circuit of switching elements Q5 and Q6 are connected in parallel, and a connection point between the switching elements Q3 and Q4 and a connection point between the switching elements Q5 and Q6. Is connected to a series circuit of an igniter IG for starting the high-pressure discharge lamp DL and the high-pressure discharge lamp DL, and is constituted by a so-called full-bridge type inverter.

The control unit 20 serves as a control unit for the boost chopper circuit. The control circuit 1 detects the voltage of the capacitor C1 to turn on / off the switching element Q1, the control circuit 2 controls the DC / DC conversion unit 12, and The control circuit 3 controls the DC / AC conversion means 13, and the control circuit 3 turns on the switching elements Q3, Q4, Q5, and Q6 by a signal output from the low frequency oscillator LF through the driving circuit B.・ Off, switching elements Q3 and Q6 are on, switching elements Q4 and Q5 are off, and switching elements Q3 and Q6 are off and switching elements Q4 and Q5 are on alternately at a frequency of about several hundred Hz Will be repeated. For this reason, the current I _DL flowing through the high pressure discharge lamp DL is a rectangular wave of about several hundred Hz.

  The control circuit 2 includes a multiplier that detects and multiplies the discharge lamp voltage Vla and the discharge lamp current Ila from the dimming ballast 10 and calculates the discharge lamp power Wla, and outputs the output Wla of the multiplier via the resistor R1. Is input to the negative side terminal of the operational amplifier OP1, a resistor R2 is connected between the negative side terminal and the output terminal of the operational amplifier OP1, and a command value Vd of electric power that changes according to the discharge lamp voltage Vla is applied to the positive side terminal. Then, when the output of the operational amplifier OP1 is input to the drive circuit A, the drive circuit A turns on and off the switching element Q2. The operational amplifier OP1 performs a feedback operation so that the lamp power matches the command value Wla *. At this time, either the duty or the frequency of the switching element Q2 may be changed, or both may be changed.

  Therefore, when the detected voltage Vla is the first output voltage V1, the power command value Vd is set to a value that becomes the first output power W1, and when the detected voltage Vla is the second output voltage V2, As long as the second output power W2 is set to a value, the illuminance can be made constant as described above without using an illuminance sensor or an integration timer.

  If the output characteristics of the discharge lamp lighting device are as described above, it is not always necessary to detect the voltage of the discharge lamp. Since the voltage of the electric lamp is generally detected, the discharge lamp voltage detection circuit can also be used as those circuits.

  As described above, according to the present embodiment, a substantially constant illuminance can be obtained at the beginning and end of the life of the discharge lamp, and it is not necessary to use the illuminance sensor or the integration timer described in the conventional example. Even when a plurality of discharge lamps are lit by a plurality of lighting devices and discharge lamps at the beginning or end of life are mixed, there is little variation in illuminance and uniform illuminance can be obtained.

  Further, by detecting the discharge lamp voltage and controlling the switching element Q2 of the DC / DC conversion means 12, a constant illuminance can be obtained, and the detection of the discharge lamp voltage is also used for other controls such as start control and abnormality protection. it can.

(Embodiment 2)
FIG. 4 shows the output characteristics of the discharge lamp lighting device according to the second embodiment of the present invention. The difference from FIG. 1 is that the value of the output power between the first output voltage V1 and the second output voltage V2 is continuously increased, and the slope of the output power with respect to the output voltage increases the output voltage. It is the point which decreased according to it. The output characteristics from the first output voltage V1 to the second output voltage V2 will be referred to as first output characteristics.

  In the first embodiment, only the two points of the initial life and the end of the life of the discharge lamp were compared, but by continuously changing as shown in FIG. 4, from the initial life to the end of the life as shown in FIG. It is possible to make the illuminance substantially constant over the entire range.

  FIG. 6 shows a main part of a specific circuit configuration example of the present embodiment. FIG. 6 shows only the control circuit 2 in FIG. 3, and the portions other than the control circuit 2 are the same as those in FIG.

  The control circuit 2 shown in FIG. 6 is different from the control circuit 2 shown in FIG. 3 in that the detected value of the discharge lamp voltage is connected to the ground via a series circuit of resistors R3 and R4 and is parallel to the resistor R4. The capacitor C3 is connected to the terminal, and a value obtained by adding the terminal voltage of the capacitor C3 and the preset DC voltage Vd is newly set as a power command value Wla *.

  The operation of the circuit will be described. FIG. 7 shows an example of the change in the discharge lamp voltage of the high-pressure discharge lamp with respect to time. At the beginning of the life, the lamp is lit at the voltage value VL, but the discharge lamp voltage gradually increases with the passage of time. In particular, the degree of change is greater at the beginning of the life, and the degree of change is smaller near the end of the life.

  Therefore, the power command value Wla * in FIG. 6 is Vd + VL at the beginning of lighting, but the value of the discharge lamp voltage increases with time, and consequently the power command value Wla *. Will also grow. In particular, since the amount of change is larger when the change in the discharge lamp voltage is closer to the beginning of lighting, as shown in FIG. 4, the command value for the discharge lamp power also changes according to the discharge lamp voltage.

  Therefore, the output characteristics as shown in FIG. 26 (b) can be easily achieved, and the illuminance can always be kept substantially constant as shown in FIG. 25 (b) in the long period from the beginning of the life to the end of the life. .

  In the present embodiment, the power at the end of the life is set to the rated power, but it is not necessarily required to be the rated power. When the power at the end of the life is smaller than the rated power, the cumulative power consumption until the end of the life can be reduced. On the contrary, when the power at the end of the life is larger than the rated power, for example, the discharge lamp is soiled. Even in the case of exceeding the light beam degradation generally considered due to the external factor, the shortage of illuminance can be compensated by the excessive input of electric power. Alternatively, as another effect, the time until the end of life in which the illuminance is substantially constant can be somewhat extended by excessive input of power.

  According to the present embodiment, a substantially constant illuminance can be obtained from the beginning of the life of the discharge lamp to the end of the life, and there is no need to use the illuminance sensor or the integration timer shown in the conventional example. In addition, a circuit for making the illuminance constant can be easily configured.

(Embodiment 3)
FIG. 8 shows a circuit of a discharge lamp lighting device according to the third embodiment of the present invention. 8 differs from FIG. 3 in that the output of the operational amplifier OP1 controls the switching element Q2 of the DC / DC converting means 12 via the drive circuit A in FIG. The output of the operational amplifier OP1 is that the switching element Q1 of the step-up chopper circuit of the DC power supply 11 is controlled via another drive circuit C. The switching element Q2 of the DC / DC converting means 12 is turned on / off via the drive circuit A by a high frequency oscillator (not shown).

  According to the present embodiment, it is easy to obtain the output characteristics of the first and second embodiments as described so far by controlling the output value of the DC power supply 11 instead of the DC / DC converting means 12. it can. Other effects are the same as in the first and second embodiments.

(Embodiment 4)
FIG. 9 shows a main circuit configuration of a discharge lamp lighting device according to the fourth embodiment of the present invention. In the present embodiment, in addition to the dimming lighting that keeps the illuminance substantially constant as described above, the same lighting device can be used to arbitrarily switch to rated lighting.

  Differences of the circuit of FIG. 9 from FIG. 6 will be described. In FIG. 6, the result obtained by adding the detected values of the DC power supply Vd and the discharge lamp voltage by the adder circuit is input to the plus side terminal of the operational amplifier OP1 as the power command value Wla *, whereas in FIG. 9, the adder circuit The switch SW1 is inserted between the positive terminal of the operational amplifier OP1 and a DC power source Vf is further connected to the switch SW1. By this changeover switch SW1, the input voltage to the operational amplifier OP1 can be selected as either Vd or Vf. Different points.

  By using this circuit, in the second embodiment, the dimming lighting output at the beginning of the life of the discharge lamp can be easily changed to the rated lighting output by switching the switch SW1. That is, if a new Vf serving as the discharge lamp power command value is set to be the rated lighting power value, it can be set to either the rated lighting state or the dimming lighting state by switching the switch SW1.

  FIG. 10 shows the output characteristics of the discharge lamp lighting device in the present embodiment, where (a) is the first output characteristic described so far, and (b) is the rated lighting state newly provided in the present embodiment. This output characteristic is referred to as a second output characteristic.

  FIG. 11 shows a state of illuminance over time in the present embodiment. FIG. 11A shows the control of constant dimming illuminance described so far, and FIG. 11B shows a second newly added in the present embodiment. The change in illuminance when the output characteristic is. In the case of (b), as described above, the light flux deteriorates at the end of the life, so that the difference in illuminance due to switching is almost eliminated.

  If this circuit is used, for example, even in an office where the window side is always bright due to sunlight, etc., and always dark in the back, if the switch SW1 is switched so that the rated lighting is in the back, it can be used. The same lighting fixture can be used.

  The switch SW1 may be attached to, for example, a fixture instead of the lighting device, and it is desirable that the switch SW1 can be manually changed even after the lighting fixture is attached to the ceiling surface or the like.

  Alternatively, if the switch SW1 is switched by either wired or wireless means, it is possible to switch between rated lighting and dimming lighting by remote operation. In this case, it is not always necessary to attach the switch SW1 to the instrument.

  As described above, according to the present embodiment, the mode of rated lighting and dimming lighting can be switched by the switch SW1, and it can be used as a discharge lamp lighting device of rated lighting, thereby expanding the range of applications. In addition, even after installation of the appliance, switching between rated lighting and dimming lighting with a constant illuminance can be easily performed.

(Embodiment 5)
FIG. 12 shows the output characteristics of the discharge lamp lighting device according to the fifth embodiment of the present invention. In the present embodiment, the output characteristics of the discharge lamp from 0 to the first output voltage V1 are described. In particular, the rated lighting output is set immediately before the output voltage V1.

  FIG. 12 differs from the output characteristic of FIG. 4 in that the characteristic of the output power in the portion below the first output voltage V1 is added, and constant current control is performed until the output voltage reaches V3. When the power becomes W2, an output characteristic is set such that W2 is constant by constant power control from V3 to V1. FIG. 13 shows the characteristics of the output current with respect to the output voltage at this time.

  By setting the output characteristics as shown in FIG. 12, since the rated lighting always shifts from dimming to dimming when starting the discharge lamp, the user can use it in either the rated lighting mode or the dimming lighting mode. Can be easily distinguished.

  FIG. 14 shows a circuit example of the present embodiment. The difference between the circuit of FIG. 14 and the control circuit 2 of FIG. 3 is that the operational amplifier OP2 for constant current control is added and the circuit can be selected by the switch SW2. A detection voltage proportional to the discharge lamp current is applied to the negative terminal of the operational amplifier OP2 via the resistor R3, and a resistor R4 is connected between the negative terminal and the output terminal of the operational amplifier OP2 to increase the current command value Id. When applied to the side terminal and the output of the operational amplifier OP2 is input to the drive circuit A via the switch SW2, the drive circuit A turns on and off the switching element Q2. The operational amplifier OP2 performs a current feedback operation so that the lamp current matches the command value Id.

  The switch SW2 can be switched between the constant current control circuit and the constant power control circuit described in the previous embodiments. As shown in FIGS. 12 and 13, the voltage of the discharge lamp is from 0 to V3. The constant current control is performed until the output voltage is in the range from V3 to V1, and the rated lighting state, that is, the output power may be controlled to be constant at W2. The switching timing of the switch SW2 can easily realize the characteristics of FIG. 12 by detecting and switching the discharge lamp voltage.

Note that the output characteristics in FIG. 12 where the output voltage is from 0 to V1 can be the same as the characteristics when rated lighting is performed. Therefore, the rated lighting circuit can be used without any special circuit change, and the characteristics of the present embodiment can be easily realized.
According to the present embodiment, it is possible to easily distinguish between the rated lighting mode and the dimming mode. In addition, since the same starting characteristics as the rated lighting are sufficient, the design becomes easy.

(Embodiment 6)
FIG. 15 shows the output characteristics of the discharge lamp lighting device according to the sixth embodiment of the present invention. The present embodiment describes the output characteristics when the voltage of the discharge lamp is from 0 to V1, and is characterized in that it is in a dimming lighting state immediately before the output voltage V1.

  FIG. 15 is different from the output characteristic of FIG. 4 in that the characteristic of the output power in the portion below the output voltage V1 is added. When the output voltage is V4, constant current control is performed, and when the output power becomes W1, From V4 to V1, output characteristics are set such that W1 is constant by constant power control. FIG. 16 shows the characteristics of the output current with respect to the output voltage at this time.

  By setting the output characteristics as shown in FIG. 15, since the illuminance does not change from the rated lighting state to the dimming lighting state as described in the fifth embodiment, the dimming is performed without changing the atmosphere after starting. It can shift to lighting.

  Also, for example, when the discharge lamp has a slow leak abnormality, the discharge lamp voltage is smaller than the initial discharge lamp voltage, that is, smaller than the voltage V1 in FIG. It is possible to prevent the discharge lamp from being damaged.

  According to the present embodiment, since the illuminance does not change from the rated lighting state to the dimming lighting state, it is possible to shift to the dimming lighting state without changing the atmosphere after starting. Further, in the case of an abnormality such as a slow leak, the dimming lighting state can be maintained to protect the discharge lamp.

(Embodiment 7)
FIG. 17 shows the output characteristics of the discharge lamp lighting device according to the seventh embodiment of the present invention. In the case of the output characteristics of FIG. 15, in order to switch between constant current control and constant power control with the voltage of the discharge lamp, in addition to the voltages V1, V2 and V3 set so far, V4 is further set and the voltage is detected. The control must be switched, which is a little complicated.

Therefore, if the output characteristics as shown in FIG. 17 are used, the output characteristics with voltages from 0 to V3 can be made the same as the characteristics when rated lighting is performed, as described in the fifth embodiment. Therefore, it is possible to use a circuit with a rated lighting without any special circuit change. After that, if the output power is set to W1 after the voltage becomes V3, it is not necessary to set V4 as shown in FIG. However, in this case, during the start-up, the power decreases at V3, so the illuminance decreases slightly at that time. FIG. 18 shows the characteristics of the output current with respect to the output voltage in FIG.
According to the present embodiment, since the same starting characteristics as those at the rated lighting time are sufficient, there is an effect that the design becomes easy.

(Embodiment 8)
FIG. 19 shows the output characteristics of the discharge lamp lighting device according to the eighth embodiment of the present invention. In this embodiment, the output characteristics when the voltage of the discharge lamp is equal to or higher than the second output voltage V2 are described, and the output is drastically reduced in either the rated lighting mode or the dimming lighting mode. The discharge lamp is prevented from entering a dangerous state due to excessive power, and the dimming lighting state is set, or the output is reduced to 0 to notify the user of the abnormality.

  FIG. 19 differs from FIG. 10 in that an output characteristic is added that abruptly reduces the output at a voltage equal to or higher than the second output voltage V2. Regardless of the dimming lighting (a) or the rated lighting (b), the output power W2 passes through the point at the voltage V2, so only one output characteristic of the voltage V2 or more is required. If the discharge lamp voltage is rapidly reduced, the user can easily recognize that the discharge lamp is at the end of its life when the discharge lamp voltage is increased.

  According to this embodiment, excessive power supply to the discharge lamp can be prevented. Further, when the discharge lamp voltage becomes high, the user can easily recognize that the discharge lamp is at the end of its life. Furthermore, the circuit for reducing the output can be used for both the rated lighting and the dimming lighting, and the control can be simplified.

  Although all the embodiments so far have been described mainly with reference to the circuits of FIGS. 3 and 8, the main circuit may be configured as shown in FIGS. 20, 21, and 22, for example. Although the details of each circuit are omitted, the DC power source 11, the DC-DC converting means (DC / DC converting means) 12, and the DC-AC converting means (DC) have been described in the above embodiments. Of the configuration of the (/ AC conversion means) 13, the circuit configuration is such that both the DC-DC conversion means (DC / DC conversion means) 12 and the DC-AC conversion means (DC / AC conversion means) 13 are used.

  Further, the voltage and current waveforms applied to the discharge lamp have been described as being rectangular waves, but may be, for example, a high frequency of several tens of KHz or more, and in short, the output as described in the embodiments so far. It goes without saying that it only has to be characteristic.

(Embodiment 9)
FIG. 23 shows a configuration example of a lighting fixture using the high pressure discharge lamp lighting device of the present invention. FIG. 23 shows an example applied to a downlight. In the figure, 31 is a discharge lamp lighting device, 32 is a lamp mounted with a high pressure discharge lamp, and 33 is wiring. By mounting the high pressure discharge lamp lighting device described in each of the embodiments 1 to 8 in this lighting fixture, the dimming illuminance can be made constant without using an illuminance sensor or an integration timer. Alternatively, a dimming system in which the dimming illuminance is constant can be constructed without using an illuminance sensor or an integration timer by using a plurality of the lighting fixtures in combination.

It is a characteristic view for operation | movement description of Embodiment 1 of this invention. It is a characteristic view for operation | movement description of Embodiment 1 of this invention. It is a circuit diagram which shows the whole structure of Embodiment 1 of this invention. It is a characteristic view for operation | movement description of Embodiment 2 of this invention. It is a characteristic view for operation | movement description of Embodiment 2 of this invention. It is a circuit diagram which shows the principal part structure of Embodiment 2 of this invention. It is a characteristic view for operation | movement description of Embodiment 2 of this invention. It is a circuit diagram which shows the whole structure of Embodiment 3 of this invention. It is a circuit diagram which shows the principal part structure of Embodiment 4 of this invention. It is a characteristic view for operation | movement description of Embodiment 4 of this invention. It is a characteristic view for operation | movement description of Embodiment 4 of this invention. It is a characteristic view for operation | movement description of Embodiment 5 of this invention. It is a characteristic view for operation | movement description of Embodiment 5 of this invention. It is a circuit diagram which shows the principal part structure of Embodiment 5 of this invention. It is a characteristic view for operation | movement description of Embodiment 6 of this invention. It is a characteristic view for operation | movement description of Embodiment 6 of this invention. It is a characteristic view for operation | movement description of Embodiment 7 of this invention. It is a characteristic view for operation | movement description of Embodiment 7 of this invention. It is a characteristic view for operation | movement description of Embodiment 8 of this invention. It is a circuit diagram which shows the other structural example of the lighting device of this invention. It is a circuit diagram which shows the further another structural example of the lighting device of this invention. It is a circuit diagram which shows another structural example of the lighting device of this invention. It is a perspective view which shows the external appearance of the illuminating device of Embodiment 9 of this invention. It is a block diagram which shows the structure of a prior art example. It is a characteristic view for operation | movement description of a prior art example. It is a characteristic view for operation | movement description of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Dimming ballast 11 DC power supply 12 DC / DC conversion means 13 DC / AC conversion means 20 Control part DL High pressure discharge lamp

Claims (13)

In a high pressure discharge lamp lighting device that supplies alternating current power to a high pressure discharge lamp to light the discharge lamp, the first output power W1 is output at the first output voltage V1, and the first output voltage V1 is output. When the second output voltage V2 is larger, the second output power W2 that is larger than the first output power W1 is output. The first output voltage V1 is a discharge lamp in which the high-pressure discharge lamp has an early life cycle. The second output voltage V2 is the voltage value of the discharge lamp at the end of its life cycle, and the first output power W1 is higher than the rated power of the high-pressure discharge lamp. A high pressure discharge lamp lighting device characterized by being small. The high pressure discharge lamp lighting device according to claim 1, wherein output power between the first output voltage V1 and the second output voltage V2 continuously increases. The slope of the output power with respect to the output voltage between the first output voltage V1 and the second output voltage V2 has a first output characteristic that decreases as the output voltage increases. Or the high pressure discharge lamp lighting device of 2. The high pressure discharge lamp lighting device comprises DC-DC conversion means connected to the output of a DC power supply and DC-AC conversion means connected to the output of the DC-DC conversion means, and both ends of the high-pressure discharge lamp. It has a detection means for detecting a voltage, and changes at least one of duty and frequency of the switching means included in the DC-DC conversion means according to the voltage detected by the detection means. The high pressure discharge lamp lighting device according to any one of claims 1 to 3. The high-pressure discharge lamp lighting device includes a DC power supply including switching means, a DC-DC conversion means connected to the output of the DC power supply, and a DC-AC conversion means connected to the output of the DC-DC conversion means. And detecting means for detecting a voltage at both ends of the high-pressure discharge lamp, and at least one of the duty and frequency of the switching means included in the DC power supply according to the voltage detected by the detecting means The high pressure discharge lamp lighting device according to claim 1, wherein the high pressure discharge lamp lighting device is changed. In the whole range from the first output voltage V1 to the second output voltage V2, the second output power W2 is output and the second output power W2 is output. 6. The high pressure discharge lamp lighting device according to claim 3, further comprising switching means for switching between the output characteristics of the high pressure discharge lamp. It has a third output characteristic that outputs the second output power W2 in the entire range from the third output voltage V3 smaller than the first output voltage V1 to the first output voltage V1. The high pressure discharge lamp lighting device according to any one of claims 1 to 6. It has a fourth output characteristic that outputs the first output power W1 in the entire range from the third output voltage V3 smaller than the first output voltage V1 to the first output voltage V1. The high pressure discharge lamp lighting device according to any one of claims 1 to 6. Current detection means for detecting a current flowing through the high-pressure discharge lamp; and a discharge lamp current stabilization circuit for controlling the discharge lamp current to be constant according to the detection output of the current detection means, and the output voltage is approximately zero. The high pressure discharge lamp lighting device according to claim 7 or 8, wherein the discharge lamp current stabilizing circuit operates in a range up to the third output voltage V3. 10. The high pressure discharge lamp lighting device according to claim 1, wherein the output power is reduced in accordance with an increase in the output voltage during a period in which the output voltage is higher than the second output voltage V <b> 2. The high-pressure discharge lamp lighting device according to any one of claims 1 to 10, wherein the second output power W2 is substantially rated power. The high-pressure discharge lamp lighting device according to any one of claims 1 to 11, wherein a ratio W1 / W2 between the first output power W1 and the second output power W2 is 0.75 or less. An illumination device comprising the high-pressure discharge lamp lighting device according to any one of claims 1 to 12.

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