JP2008060051A - Discharge lamp lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a discharge lamp lighting device of an inexpensive constitution in which a discharge lamp is turned on when switch contacts installed at a circuit are open and generation of a high voltage in a discharge lamp connector is evaded when the contacts are closed. <P>SOLUTION: This is equipped with a high voltage pulse generating circuit to start a discharge lamp valve 8 by generating the high voltage pulse using electric charge accumulated in a capacitor 5 via a charge resistor 4, a discharge lamp connector to supply a lighting voltage from an H type bridge part 3 and the high voltage pulse from a high voltage generating circuit to the discharge lamp valve 8, a discharge switch S3 which is closed when the discharge lamp valve 8 is removed from the discharge lamp connector, and a discharge resister 7 to discharge the electric charge accumulated in the capacitor 5 when the discharge switch S3 is closed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device that suppresses application of a high starting voltage to a discharge lamp connector when a discharge lamp bulb is not attached to the discharge lamp connector.

For example, if the lighting operation is performed in a unique state where the discharge lamp bulb for the headlamp is removed from the connector for repair or the like, there is a risk of electric shock coming into contact with the conductive portion of the connector at a short timing when high voltage is generated. is there. In order to avoid such a risk, there is a discharge lamp lighting device configured so that a high starting voltage is not applied to the connector when the discharge lamp bulb is removed.
Such a device is configured such that a contact is provided on the power supply wiring for lighting, and when the discharge lamp bulb and the connector are attached to the fixed member, the above contact is closed and the discharge lamp bulb is energized through the connector. (For example, refer to Patent Document 1). However, since the power supply current required by the discharge lamp lighting device exceeds 10 [A] at the maximum, it is necessary to use a large one corresponding to a large current for the terminal incorporated in the connector of the discharge lamp in the above device configuration. There is. Since the size of the connector and the electric wire inevitably becomes large, it is not preferable for a discharge lamp lighting device arranged in a limited narrow space such as an in-vehicle headlamp.

  In addition, when a contact is provided on the socket, that is, the discharge lamp connector, and the discharge lamp bulb is removed from the discharge lamp connector, the contact moves to short-circuit the power supply and lighting circuit, and an excessive current is applied for a short time for protection. There is a circuit that causes the circuit to determine abnormality and stop the voltage output (for example, see Patent Document 2). In order to avoid danger, this device is intentionally temporarily stopped after an abnormal operation with a large output is performed, which is electrically undesirable because it adds stress to the circuit of the discharge lamp lighting device.

  There is also provided a switch that closes when a discharge lamp bulb is attached to a discharge lamp connector having an igniter, and a switch that closes when the discharge lamp connector is attached to a lamp housing. There is a detector that detects that the igniter has been disconnected, and stops the generation of a high voltage when the switch is opened to detect that the igniter is disconnected. (For example, refer to Patent Document 3). This device requires two independent wires in addition to the wires for supplying power to the discharge lamp, and requires complicated wires with increased costs. It is not preferable for a discharge lamp lighting device.

  In addition, if a bulb detection switch is installed in the socket, and the lamp cap of the discharge lamp bulb is normally attached to the socket, the bulb detection switch becomes conductive and the voltage generated in the bulb detection circuit becomes high, and the discharge lamp bulb is attached. If not, the valve detection switch is opened and the voltage of the valve detection circuit becomes low. The DC booster circuit that generates the discharge lamp bulb lighting voltage operates when the voltage of the bulb detector circuit is high, and the DC booster circuit stops operating when the voltage of the bulb detector circuit is low. There is one that prevents electric shock when the discharge lamp bulb is not attached to the socket (for example, see Patent Document 4). This device requires a valve detection switch and wiring for transmitting the operation of the switch to the valve detection circuit. Therefore, it is not preferable for a discharge lamp lighting device for an in-vehicle headlamp disposed in a limited narrow space because it involves the addition of parts accompanying a cost increase and complicated wiring.

  In addition, when the discharge lamp connector connected to the discharge lamp bulb is provided with an auxiliary terminal that contacts the outer peripheral terminal of the discharge lamp bulb, and the discharge lamp bulb is attached to the discharge lamp connector, the DC voltage output from the lighting circuit is discharged. Is supplied to the igniter main circuit via an auxiliary terminal which is in contact with the outer peripheral terminal. If the discharge lamp bulb is not attached, there is no outer peripheral terminal, so that no voltage is applied to the auxiliary terminal, and there is one that does not supply power to the igniter main circuit (for example, see Patent Document 5). This device needs to use a highly reliable structure and material for the auxiliary terminal connected to the outer peripheral terminal of the discharge lamp connector. Accordingly, in order to obtain an appropriate material and structure, the cost of the discharge lamp lighting device increases with an increase in cost.

Japanese Patent Laid-Open No. 63-231801 (pages 2, 3 and 1) Japanese Utility Model Publication No. 3-1845 (pages 6-9, FIGS. 1 and 2) Japanese Patent Laid-Open No. 7-114819 (pages 3, 4 and FIG. 1) Japanese Unexamined Patent Publication No. 2000-21585 (page 4, FIG. 1) JP 2001-102189 A (page 4, FIGS. 1 and 2)

  Since the conventional discharge lamp lighting device is configured as described above, the discharge lamp lights when the switch is closed or when the contact of the connector is in contact. It is necessary to use highly reliable switches to ensure, and inexpensive materials and structures cannot be used, so it is essential to increase costs. In addition, the configuration in which the switch is lit when the switch is opened also has a problem that it is electrically undesirable because excessive stress is temporarily applied to the circuit.

  The present invention has been made to solve the above-described problems. When the switch contact provided in the circuit is opened, the discharge lamp is turned on, and when the contact is closed, a high voltage is generated at the discharge lamp connector. An object of the present invention is to obtain a discharge lamp lighting device having a low-cost configuration that avoids this.

  The discharge lamp lighting device according to the present invention has a discharge means for discharging the electric charge accumulated in the capacitor of the high voltage pulse generating means for starting the discharge lamp bulb when the discharge lamp bulb is detached from the discharge lamp connector. It is to be prepared.

  According to the present invention, when the discharge lamp bulb is removed from the discharge lamp connector, the electric charge accumulated in the capacitor used for generating the high voltage pulse is discharged, so that the discharge lamp bulb is removed. The high-voltage electric shock can be prevented with an inexpensive configuration.

An embodiment of the present invention will be described below.
Embodiment 1 FIG.
Faults that occur in switches or connectors include the phenomenon of “no transition from ON to OFF” due to contact welding, but most are caused by poor contact, such as contact oxidation, fouling, and poor caulking. is there. Failures that do not transition from OFF to ON, such as the disconnection of the conductive wire for wiring, are overwhelmingly more frequently generated. Therefore, if the discharge lamp is turned on when the contact is open, the possibility of impairing the original lighting function due to the failure of the contact is reduced, and a high voltage is applied to the connector from which the discharge lamp bulb has been removed. A configuration that avoids the risk of occurrence of a fault can be realized at an appropriate cost.

  1 is a circuit diagram showing a configuration of a discharge lamp lighting device according to Embodiment 1 of the present invention. For example, a power source 1 composed of a battery that supplies a DC voltage of 12 [V] is connected to an input terminal of a DC / DC converter 2 via a power switch S1. The DC / DC converter 2 has +400 [V] and 0 [V] output terminals connected to the two input terminals of the H-type bridge unit 3, respectively. The H-type bridge unit 3 constitutes an H-type bridge circuit using, for example, a plurality of switching transistors, and has two input terminals, a low-potential side output terminal, and a high-potential side output terminal. ing.

  Further, the DC / DC converter 2 has an output terminal of −800 [V] connected to one end of the charging resistor 4. The other end of the charging resistor 4 is connected to one end of the capacitor 5 and one end of the GAP switch S2. The other end of the capacitor 5 is connected to the output terminal on the high potential side of the H-type bridge unit 3 and one end of the primary side winding of the transformer 6. The output terminal on the low potential side of the H-type bridge unit 3 is connected to the connector terminal 13 on the low potential side. The other end of the GAP switch S2 is connected to the other end of the primary winding of the transformer 6. One end of the primary side winding of the transformer 6 is connected to one end of the secondary side winding of the transformer 6. The other end of the secondary winding of the transformer 6 is connected to the high potential side connector terminal 13.

One end of the discharge resistor 7 is connected to the connection point of the other end of the charging resistor 4, one end of the capacitor 5, and one end of the GAP switch S 2. One end of a discharge switch S3 is connected to the other end of the discharge resistor 7. The other end of the discharge switch S3 is connected to the output terminal on the high potential side of the H-bridge 3 described above, the other end of the capacitor 5, one end of the primary side winding of the transformer 6 and one end of the secondary side winding. It is connected. The discharge switch S3 has a normally closed mechanical contact. As will be described later, when the discharge lamp bulb 8 is attached to the discharge lamp connector, the discharge switch S3 is pushed and opened by the push rod 12, and the discharge lamp bulb 8 is removed. It is an ON / OFF switch that closes when the
The discharge lamp lighting device according to the first embodiment includes a control unit including a DC / DC converter 2, an H-type bridge unit 3, and a charging resistor 4, a capacitor 5, a transformer 6, a discharge resistor 7, and a GAP switch S2. And a high voltage pulse generating circuit.
Further, the discharge lamp lighting device shown in FIG. 1 is a discharge circuit of the capacitor 5 constituted by the discharge resistor 7 and the discharge switch S3 connected as described above, more specifically, the discharge resistor 7 and the discharge switch S3 connected in series. Thus, a discharge circuit in which both ends of the capacitor 5 are connected is provided.

  2 and 3 are explanatory diagrams showing the configuration of the discharge lamp lighting device according to the first embodiment. 2 and 3 are longitudinal sectional views of the discharge lamp connector 10 of the discharge lamp lighting device. FIG. 2 shows a state in which the discharge lamp bulb 8 is not attached to the discharge lamp connector 10, and FIG. A state in which the discharge lamp bulb 8 is attached is shown. The same parts as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. The discharge lamp connector 10 includes the capacitor 5, the transformer 6, the discharge resistor 7, the GAP switch S2, the discharge switch S3, the connector terminal 13, the push rod 12 and the like shown in FIG. In FIG. 1, the connection point of the capacitor 5, the GAP switch S2 and the discharge resistor 7, the connector terminal 13 on the low potential side, and the connection point of the capacitor 5, the transformer 6 and the discharge switch S3 are respectively connected to its own connection terminals. A cable connector 14 is provided for connecting and connecting these connection terminals to the H-shaped bridge portion 3 and the charging resistor 4 provided outside the discharge lamp connector 10 by cables.

  As shown in FIG. 2, the discharge lamp connector 10 includes, for example, a socket portion 11 for inserting a connection terminal portion of the discharge lamp bulb 8 on the upper surface of the connector main body 10a. Further, on the bottom end surface of the socket portion 11, connector terminals 13 on the high potential side and the low potential side are installed. Further, the push rod 12 protrudes from the bottom end surface and is provided to swing within the opening of the socket portion 11. One end of the lever member S3a of the discharge switch S3 is connected to the push rod 12 inside the connector body 10a. The other end of the lever member S3a is connected to a wiring conductor 15 disposed inside the connector body 10a, for example, formed by processing a metal plate or the like. As shown in FIG. 1, circuit wiring of the capacitor 5, the transformer 6, the discharge resistor 7, and the GAP switch S2 is performed by the wiring conductor 15. That is, the wiring lead wire 15 is a lead frame that constitutes each circuit arranged inside the connector main body 10a, specifically, a high-voltage pulse generation circuit and a discharge circuit. Alternatively, a metal member having a leaf spring characteristic may be used as a lead frame, and the lever member S3a may be integrally formed with the wiring conductor 15 as a cantilever spring. Since the lever member S3a is made of a conductive material, the push rod 12 is made of an insulating material to prevent unnecessary voltage application to the discharge lamp bulb 8.

A contact member S3b connected to the discharge resistor 7 is disposed in the vicinity of the lever member S3a, and a protruding portion of the contact member S3b protruding toward the lever member S3a and a lever member connected to the push rod 12 A contact point of the discharge switch S3 is formed by a portion near one end of S3a. Note that the contact member S3b is included in the wiring lead wire 15 forming the above-described circuit wiring, and is connected to the other end of the discharge resistor 7 as described above. As shown in FIG. 2, the lever member S3a is urged toward the protruding portion of the contact member S3b in detail so that the discharge switch S3 is closed when nothing is in contact with the push rod 12. Is provided.
Further, as shown in FIG. 3, when the discharge lamp bulb 8 is attached to the socket portion 11 of the discharge lamp connector 10, the push rod 12 contacts the outer peripheral terminal 8a of the discharge lamp bulb 8 and the outer peripheral side of the socket portion 12. It is provided so as to swing. Thus, when the push rod 12 is swung, the lever member S3a is disposed so as to be separated from the contact member S3b. When the push rod 12 moves as described above, the lever member S3a moves toward the outer periphery of the connector body 10a, so that the contact member S3b is disposed on the center side of the socket portion 11 with respect to the lever member S3a.

In this example, the push rod 12 is arranged so as to be in contact with the outer peripheral terminal 8a of the discharge lamp bulb 8. However, when the discharge lamp bulb 8 is attached to the socket portion 11, the discharge switch S3 is opened. Any configuration may be used, and the arrangement configuration of the push rod 12 and the discharge switch S3 are not limited to those described above.
The discharge lamp connector 10 shown in FIGS. 2 and 3 includes the capacitor 5, the transformer 6 and the GAP switch S2 forming a high voltage pulse generating circuit inside the connector main body 10a as described above, and the discharge switch S3 forming the discharge circuit. The discharge resistor 7 is disposed, and the push rod 12 for opening the contact of the discharge switch S3 and the connector terminal 13 connected to the terminal of the discharge lamp bulb 8 are provided and integrated.

Next, the operation will be described.
First, the general operation when the power switch S1 is turned on with the discharge lamp bulb 8 attached to the discharge lamp connector 10 will be described.
As shown in FIG. 3, when the discharge lamp bulb 8 is attached to the discharge lamp connector 10, the discharge switch S3 is opened. When the power switch S <b> 1 is closed, the DC voltage 12 [V] is supplied from the battery 1 to the DC / DC converter 2. The DC / DC converter 2 boosts the input DC voltage and outputs +400 [V] and 0 [V] to the H-type bridge unit 3. When the H-type bridge unit 3 starts operating, a rated voltage used for discharge lighting is applied between the electrodes of the discharge lamp bulb 8 through the secondary winding of the transformer 6.

  Further, when the DC / DC converter 2 starts to operate, it is constituted by a high voltage pulse generating circuit for generating a high voltage pulse for starting discharge lighting of the discharge lamp bulb 8, that is, a capacitor 5, a transformer 6 and a GAP switch S2. When the circuit operates, a high voltage is applied to the capacitor 5 connected between the charging resistor 4 to which −800 [V] is applied and the output terminal on the high potential side of the H-type bridge unit 3. 5 is charged. When charging proceeds and the voltage across the capacitor 5 reaches, for example, 800 [V], the GAP switch S2 is turned on by the voltage / current characteristics of the GAP switch S2, and the charge accumulated in the capacitor 5 is discharged. The Then, a large current instantaneously flows in the primary side winding of the transformer 6 and a high voltage pulse is generated in the secondary side winding. This high voltage pulse is applied to the discharge lamp bulb 8 to cause breakdown and start discharge lighting.

In order to light the discharge lamp bulb 8, it is necessary to apply a rated voltage to the electrodes of the discharge lamp bulb 8 as described above and to apply a high voltage pulse that electrically breaks down between the electrodes. Since the electrical resistance between the electrodes of the discharge lamp bulb 8 before lighting is extremely high and no current flows, the control unit comprising the DC / DC converter 2 and the H-type bridge circuit 3 shown in FIG. Since no load is applied regardless of whether or not the discharge lamp bulb 8 is mounted, that is, an open state, the discharge lamp bulb 8 is not connected unless it is configured to operate using a signal indicating whether or not the discharge lamp is mounted. When the lighting operation is performed regardless of the above, a high voltage pulse is generated as described above.
When the discharge lamp bulb 8 is removed for maintenance of the vehicle and the power switch S1 is turned on, the high voltage pulse generation circuit generates a high voltage pulse. This high voltage pulse is generated between the terminals of the discharge lamp connector 10. Because it only discharges inside, it does not lead to an accident. However, there is a risk of high-pressure electric shock if the situation where the hand touches the connector terminal 13 of the discharge lamp connector 10 overlaps in the above situation.

  In the discharge lamp lighting device according to the first embodiment, when the discharge lamp bulb 8 is removed from the discharge lamp connector 10, that is, in the state shown in FIG. 2, the discharge switch S3 is closed and both ends of the capacitor 5 are discharged. It is connected by the circuit. When the discharge circuit is formed in this way, even if the power switch S1 is closed and the DC / DC converter 2 and the H-type bridge unit 3 operate, the charge accumulated in the capacitor 5 is removed by the discharge circuit, The voltage across the capacitor 5 cannot reach the value at which the GAP switch S2 is turned on. Therefore, the high voltage pulse generation circuit cannot generate a high voltage pulse, and a high voltage is not applied to the discharge lamp connector 10.

In the above electric shock, the discharge lamp bulb 8 is removed from the discharge lamp connector 10 for some reason, the power switch S1 is turned on without recognizing this, and the connector terminal of the discharge lamp connector 10 is generated at a short timing when a high voltage pulse for starting is generated. Since this occurs when touching 13, the occurrence rate is extremely low. The generation stop of the high voltage pulse is a processing operation for avoiding an emergency.
In order to suppress the cost of the portion that is unlikely to operate in this way, the discharge lamp lighting device according to Embodiment 1 avoids a configuration in which a switch or the like is opened in an abnormal situation to turn off the circuit operation, in other words, In order to avoid using a highly reliable switch or the like in order to ensure that the discharge lamp bulb 8 is lit when the switch or the like is closed and to ensure a lighting function, the discharge circuit of the capacitor 5 as described above. It has. This discharge circuit is configured such that when the discharge lamp bulb 8 is not attached to the discharge lamp connector 10 as described above, the discharge switch S3 is closed, and in other words, the discharge switch S3 is opened. Therefore, even when the discharge switch S3 cannot perform the switching function due to the above-described general event, the lighting function of the discharge lamp bulb 8 is preferentially maintained. can do. Further, since the lighting voltage and the starting high voltage pulse are not applied to the discharge switch S3, a switch having a relatively inexpensive mechanical contact can be used as the discharge switch S3.

  When the discharge switch S3 is closed, a current having a magnitude corresponding to the amount of charge accumulated in the capacitor 5 flows in the discharge circuit. Therefore, if the resistance value of the discharge circuit is small, a large current flows, and the discharge switch S3 There is a risk of welding the contact. In order to prevent such welding of the contacts, a discharge resistor 7 for limiting a current flowing in the discharge circuit is connected in series between the capacitor 5 and the discharge switch S3.

  The discharge resistor 7 has one end connected to the connection point between the charge resistor 4 and the capacitor 5 and the other end connected to the discharge switch S3. Therefore, as shown in FIG. 1, the charging resistor 4 and the discharging resistor 7 are connected in series, and the voltage divided by the charging resistor 4 and the discharging resistor 7 is applied to one end of the capacitor 5. Become. When the resistance value of the charging resistor 4 is R1 and the resistance value of the discharging resistor 7 is R2, the voltage Vc divided by the charging resistor 4 and the discharging resistor 7 and applied to one end of the capacitor 5 is Vc = R1 / ( R1 + R2). The voltage output from the H-type bridge unit 3 is applied to the other end of the capacitor 5 as shown in FIG. 1, and the potential difference between the voltage applied from the H-type bridge unit 3 and the voltage Vc is the capacitor. 5 is the voltage at both ends.

  If the resistance value R2 of the discharge resistor 7 is set large, the discharge current decreases, and the voltage across the capacitor 5 may exceed the breakdown voltage of the GAP switch S2. When the voltage across the capacitor 5 exceeds, for example, 800 [V], the GAP switch S2 is turned on and a high voltage pulse is generated. Therefore, the resistance value R1 of the charging resistor 4 and the resistance value R2 of the discharging resistor 7 Are set within a range in which the GAP switch S2 is not turned ON. In other words, when the discharge switch S3 is closed and a discharge current is flowing through the discharge circuit, the voltage across the capacitor 5, that is, the voltage applied across the discharge resistor 7 is the voltage at which the GAP switch S2 is turned on. The resistance value R1 of the charging resistor 4 and the resistance value R2 of the discharging resistor 7 are set so as to be smaller.

As described above, according to the first embodiment, the discharge switch S3 which is closed when the discharge lamp bulb 8 is detached from the discharge lamp connector 10, and both ends of the capacitor 5 are connected when the discharge switch S3 is closed. Since the discharge resistor 7 for discharging the accumulated charge is provided, even if the power switch S1 is turned on when the discharge lamp bulb 8 is not attached to the discharge lamp connector 10, a high voltage pulse is applied to the discharge lamp connector 10. This prevents the use of an unnecessary discharge lamp and prevents electric shock.
Further, since the high voltage pulse for starting the discharge lamp bulb 8 and the lighting voltage are not applied to the discharge switch S3, the discharge switch S3 having a low standard such as withstand voltage can be used. The effect is that electric shock can be prevented with a simple structure.
In addition, the discharge circuit can be made small using a small discharge switch S3 having a low withstand voltage, and it is easy to integrate the discharge circuit with the discharge lamp connector.

Embodiment 2. FIG.
FIG. 4 is an explanatory view showing the structure of a discharge lamp lighting device according to Embodiment 2 of the present invention. The same reference numerals are used for parts that are the same as or correspond to those shown in FIGS. The discharge lamp bulb 9 is provided with a projection 9a such as a claw used to prevent the discharge lamp connector from coming off on the outer periphery of the bulb base 9b.
In the discharge lamp lighting device according to the second embodiment, the discharge lamp bulb 9 shown at the top of FIG. 4 is mounted on, for example, the discharge lamp connector 20 including the high voltage pulse generation circuit and the discharge circuit described in the first embodiment. The power source 1, the power switch S1, the DC / DC converter 2, the H-type bridge unit 3, the charging resistor 4 and the like are similarly provided, and the discharge switch S4 is replaced with the discharge switch S3 shown in FIG. I have. Here, a description of the same parts as those described in the first embodiment and the same operation will be omitted.

  On the side wall portion of the socket portion 21 of the discharge lamp connector 20 into which the connection terminal of the discharge lamp bulb 9 is inserted, a notch 22 formed in an approximately L shape from the opening end portion of the socket portion 21 is provided. As described above, the substantially L-shaped notch 22 is formed on one side extending from the opening end of the socket portion 21 toward the bottom end surface of the socket portion 21 and in the outer peripheral direction of the opening portion of the socket portion 21. This is composed of an extended guide portion 22a on one side, and includes a discharge switch S4 as will be described later.

  FIG. 4 is an enlarged view of the portion A provided with the notch 22 of the socket portion 21 shown at the uppermost stage in the drawing, and shows the notch 22 and the projection 9a of the discharge lamp bulb 9 joined at this portion A. Each state is illustrated as states A1 to A4. In addition, the lever member S4a and the contact member S4b shown in the state A1 and the state A3 are members constituting the contact portion of the discharge switch S4, which is not shown in FIG. 4, and are shown in FIGS. This corresponds to the lever member S3a and the contact member S3b of the discharge switch S3. The lever member S4a is urged so as to contact the contact member S4b. Further, the lever member S4a is arranged in parallel with the guide portion 22a of the notch 22, and is cantilevered as the above-described lever member S3a. The end portion on the opposite side of the support portion faces the guide portion 22a. Protruding protrusions are provided.

  When the discharge lamp bulb 9 is connected to the discharge lamp connector 20 shown in FIG. 4, the positions of the socket portion 21 and the discharge lamp bulb 9 so that the projection 9a is inserted into the substantially L-shaped notch 22 as described above. After aligning, the discharge lamp bulb 9 is inserted into the socket portion 21. Then, the protrusion 9a enters from the end of the notch 22, and the protrusion 9a contacts the edge of the guide portion 22a as in the state A1 shown in FIG. At this time, the protrusion 9a can move in the direction of the arrow shown in the state A2, that is, toward the opening of the socket portion 21, and the discharge lamp bulb 9 can be easily removed from the discharge lamp connector 20. When the projection 9a is present at the position indicated as the state A1, that is, the L-shaped corner, the lever member S4a of the discharge switch S4 forming the discharge circuit comes into contact with the contact member S4b, and from the cutting portion of the guide portion 22a The protrusion of the aforementioned lever member S4a is exposed. The discharge switch S4 is closed in such a state, and the discharge circuit including the discharge switch S4 and the discharge resistor 7 is also in a state of discharging the charge of the capacitor 5.

As shown in state A1, after the discharge lamp bulb 9 is inserted into the discharge lamp connector 20, when the discharge lamp bulb 9 is rotated, as shown in state A3, the protrusion 9a goes to the back of the guide portion 22a, that is, It moves upward in the drawing and comes into contact with the protrusion of the lever member S4a, and the lever member S4a is pushed and pulled away from the contact member S4b. When the discharge switch S4 is thus opened, the projection 9a is fixed to the terminal portion of the guide portion 22a as in the state A4, and the discharge lamp bulb 9 is fixed to the discharge lamp connector 20 in a predetermined direction. . As described above, when the discharge lamp bulb 9 is securely fixed to the discharge lamp connector 20 at a predetermined position, the discharge circuit is opened and the starting charge is accumulated in the capacitor 5 so that the high voltage pulse is generated. Can be generated.
Thus, the projection 9a of the discharge lamp bulb 9 acts in the same manner as the push rod 12 described in the first embodiment, and opens the contact of the discharge switch S4.

  The discharge lamp bulb is provided with a plurality of protrusions, and there is a discharge lamp connector having a larger number of notches than the above-mentioned protrusions so that the discharge lamp connector can be connected by changing the direction. For example, when the discharge lamp bulb 9 is provided with two projections 9a so as to face each other on the outer periphery of the bulb base 9b, the discharge lamp connector 20 is notched at four locations at equal intervals on the outer peripheral portion of the bulb base 9b. Is provided, the discharge switch S4 is installed in two adjacent cutouts 22. When the discharge switch S4 is installed in this way, no matter which direction the discharge lamp bulb 9 is directed and fixed to the discharge lamp connector 20, the projection 9a comes into contact with any one of the discharge switches S4. When the bulb 9 is rotated and fixed securely, a high voltage pulse for starting lighting can be generated. When two discharge switches S4 are provided in this way, as shown in the explanatory diagram of FIG. 5, when two discharge switches S4 are connected in series and one of the discharge switches S4 is opened, the capacitor 5 is discharged. The discharge circuit is configured so as not to perform it.

  As described above, according to the second embodiment, when the discharge switch S4 is installed in the notch 22 of the discharge lamp connector 20, and the discharge lamp bulb 9 is rotated and the protrusion 9a is fixed at a predetermined position, the discharge switch Since S4 is opened and the discharge circuit does not operate, a high voltage pulse for starting can be generated when the discharge lamp bulb 9 is securely fixed to the discharge lamp connector 20 at a predetermined position. There is an effect that it is possible to surely avoid the danger.

  Further, by connecting a plurality of discharge switches S4 in series, any one of the discharge switches S4 can be opened / closed according to the mounting / removal of the discharge lamp bulb 9, and the operation of the discharge circuit can be switched appropriately. There is an effect.

It is a circuit diagram which shows the structure of the discharge lamp lighting device by Embodiment 1 of this invention. It is explanatory drawing which shows the structure of the discharge lamp lighting device by Embodiment 1. FIG. It is explanatory drawing which shows the structure of the discharge lamp lighting device by Embodiment 1. FIG. It is explanatory drawing which shows the structure of the discharge lamp lighting device by Embodiment 2 of this invention. It is explanatory drawing which shows the structure of the discharge lamp lighting device by Embodiment 2. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Power supply, 2 DC / DC converter, 3 H bridge part, 4 Charging resistance, 5 Capacitor, 6 Transformer, 7 Discharge resistance, 8, 9 Discharge lamp bulb, 8a Outer terminal, 9a Protrusion, 9b Valve base, 10, 20 Discharge lamp connector, 10a connector body, 11 socket part, 12 push rod, 13 connector terminal, 14 cable connector, 15 wire for wiring, 21 socket part, 22 notch, 22a guide part, S1 power switch, S2 GAP switch, S3 , S4 discharge switch, 3Sa, S4a lever member, S3b, S4b contact member.

Claims (7)

A high voltage pulse generating means for starting the lighting of the discharge lamp bulb by generating a high voltage pulse using the electric charge accumulated in the capacitor via the charging resistor; and the lighting voltage controlled by the control means and the high voltage pulse are released. In a discharge lamp lighting device comprising a discharge lamp connector for supplying to a light bulb,
A discharge lamp lighting device comprising: discharge means for discharging charges accumulated in the capacitor when a discharge lamp bulb is removed from the discharge lamp connector.   2. The discharge lamp lighting device according to claim 1, wherein the discharge means includes a discharge switch that is closed when the discharge lamp bulb is removed from the discharge lamp connector.   The discharge lamp lighting device according to claim 1 or 2, wherein the high voltage pulse generating means and the discharging means are integrated with the discharge lamp connector.   The discharge lamp lighting device according to claim 2 or 3, wherein the discharge means includes a discharge resistor for limiting a discharge current between the capacitor and the discharge switch. A discharge resistor is provided with one end connected to the connection point between the capacitor and the charge resistor and the other end connected to the discharge switch.
When the discharge switch is closed to discharge the electric charge accumulated in the capacitor, the voltage applied to the discharge resistor is smaller than the voltage when the high voltage pulse generating means generates a high voltage pulse. The discharge lamp lighting device according to claim 4, wherein resistance values of the charging resistor and the discharging resistor are set so as to be.   When a discharge lamp bulb provided with a projection for preventing a discharge lamp connector and a discharge lamp connector provided with a notch for fixing the projection by rotation of the discharge lamp connector are connected, the projection is fixed to the connector. The discharge lamp lighting device according to any one of claims 1 to 5, further comprising: a discharge unit that performs a discharge operation when leaving the position.   The discharge lamp lighting device according to any one of claims 2 to 6, wherein the discharge switch constitutes a contact point by a member integrally formed with the wiring member.

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