JP6169041B2 - Power supply device, cooling device, and semiconductor light source lighting device - Google Patents

Description

  The present invention relates to a power supply device that generates desired power from a constant current power supply and supplies it to a load, a cooling device incorporating the power supply device, and a semiconductor light source lighting device including the constant current power supply and the power supply device It is.

  Recent LEDs (semiconductor light sources, light-emitting diodes, etc.) have the advantages of easy maintenance and energy saving, that is, low carbon dioxide generation, because the amount of emitted light is increased while the power consumption is reduced and the lifetime is long. It has. Therefore, LEDs are used in place of conventional incandescent bulbs as light sources for in-vehicle lamps (for example, headlamps and brake lights).

  In-vehicle lamps that use LEDs as light sources may be provided with a cooling device that reduces the temperature of the LEDs. The cooling device includes a motor and a rotatable fan, and sends a wind generated by the rotational movement of the fan to the LED or a heat sink that is thermally coupled to the LED, thereby suppressing a temperature rise due to self-heating of the LED. The long life of the LED is not impaired.

  Conventionally, the wiring for electrically connecting the LED lighting circuit and the LED and the wiring for electrically connecting the driving circuit of the cooling device and the cooling device have been provided separately. In an in-vehicle lamp, wiring is shared by connecting an LED and a cooling device in series.

JP 2009-129564 A

In the configuration of Patent Document 1, it is necessary to match the rated current of the LED and the rated current of the cooling device, and a plurality of cooling devices must be prepared according to the rated current of the LED to be lit. Therefore, a switch is provided in parallel with the cooling device, and PWM (Pulse Width Modulation) control is performed to keep the average current below the rated current. In this case, a dedicated device for connecting the cooling device and the switch in parallel is used. There was a problem that wiring was required. In addition, since a cooling device must be connected to an LED that is close to the GND potential among a plurality of LEDs connected in series, when the cooling device is placed at an optimal position for cooling, a smooth wiring cannot be achieved. There was also a problem of increasing the length.
In other words, it is desirable that the cooling device does not need to be matched with the rated current of the LED and that the connection position is not limited.

  The above-mentioned problem is not limited to the case where the LED and the cooling device are connected to the constant current power source, but also exists when two loads having different rated currents are connected, for example, an LED and an incandescent bulb. To do.

  The present invention has been made to solve the above-described problems, and includes a power supply device that generates and supplies power suitable for loads with different rated currents from a constant current power supply, and a cooling device incorporating the power supply device It is another object of the present invention to provide a semiconductor light source lighting device including a constant current power source and the power source device.

  The power supply device according to the present invention is connected in series with the first load between the outputs of the constant current power supply that outputs the first current, and applies the first current supplied to the first load from the constant current power supply. This is converted into a second current different from the first current or a desired voltage, and supplied to a second load connected to the output side of the power supply apparatus.

  A cooling device according to the present invention is connected in series with a semiconductor light source between outputs of a constant current power source that outputs a first current for lighting the semiconductor light source, and operates a fan that cools the semiconductor light source. A motor and a control circuit that converts the first current into a second current or a desired voltage different from the first current and drives the motor are provided.

  A semiconductor light source lighting device according to the present invention lights a semiconductor light source provided in a lamp, generates a first current for lighting a semiconductor light source from a power source, and outputs the first current, and a constant current power source A cooling unit connected in series with the semiconductor light source between the outputs of the units, the cooling unit operating a fan for cooling the semiconductor light source, and a second current different from the first current. And a control circuit that converts the current into a desired voltage or a desired voltage and drives the motor.

  According to the present invention, the power supply device converts the first current supplied to the first load into the second current or a desired voltage and supplies it to the second load. Even if the rated current or voltage of the load and the second load are different, it is possible to supply electric power suitable for the second load.

  According to this aspect of the invention, the power supply device provided in the cooling device supplies the cooling fan with the electric power obtained by converting the energized first current, so that the cooling fan can be operated.

  According to the present invention, the power supply device included in the semiconductor light source lighting device operates the cooling fan with the electric power converted from the current supplied to the semiconductor light source, so that the semiconductor light source can be turned on while cooling.

It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 1 of this invention is applied. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 2 of this invention is applied. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 3 of this invention is applied. 6 is a graph schematically showing current and voltage of a cooling device according to Embodiment 3. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 4 of this invention is applied. 6 is a graph schematically showing current and voltage of a cooling device according to a fourth embodiment. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 5 of this invention is applied. It is the graph which represented typically the electric current and voltage of the cooling device which concerns on Embodiment 5, and shows the case where the lighting current of an LED module is larger than the rated current of a cooling fan. It is the graph which represented typically the electric current and voltage of the cooling device which concerns on Embodiment 5, and shows the case where the lighting current of an LED module is smaller than the rated current of a cooling fan. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 6 of this invention is applied. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 7 of this invention is applied. It is a circuit diagram which shows the structural example of the vehicle lamp to which the cooling device which concerns on Embodiment 8 of this invention is applied. 10 is a graph schematically showing a drive sequence of a cooling device according to an eighth embodiment.

Embodiment 1 FIG.
As shown in FIG. 1, it is a circuit diagram which shows the structural example of the vehicle-mounted lamp to which the cooling device 15 which concerns on Embodiment 1 is applied. In this in-vehicle lamp, LED modules 13 and 14 (first load) and a power control circuit 16 (power supply device) are connected in series on the output side of the LED lighting device 12 (constant current power supply). The cooling fan 17 (second load) is connected to the output side. The LED modules 13 and 14 are used as light sources for various in-vehicle lamps such as headlamps and brake lights.

  The LED lighting device 12 converts the current of the in-vehicle power source 1, which is an in-vehicle battery, into a lighting current (first current) for the LED modules 13 and 14, and outputs the current to light the LED modules 13 and 14. The power control circuit 16 converts the lighting current supplied to the LED modules 13 and 14 into a second current or a desired voltage and outputs it, and operates the cooling fan 17. The LED modules 13 and 14 and the cooling device 15 need only be connected in series, and there is no restriction on the connection order.

  When the switch 2 is turned on, power is supplied from the control power supply unit 9 to the control unit 10, and the control unit 10 recognizes that the switch 2 is turned on. The control unit 10 controls the FET (field effect transistor) 5 of the first DC / DC converter unit 3 to be turned on / off at a high speed by the DC / DC FET operation output, thereby boosting or stepping down the input voltage, and the LED module 13. , 14 are turned on, and the same current as the lighting current of the LED modules 13, 14 is supplied to the cooling device 15 to operate the cooling fan 17.

  The inverting amplifier 11 inverts and amplifies the voltage of the current detection resistor 8 and inputs it to the control unit 10 (output current input in FIG. 1). The control unit 10 recognizes the lighting current of the LED modules 13 and 14 by detecting the voltage input from the inverting amplifier 11. Moreover, the control part 10 detects the voltage of A point (output voltage input of FIG. 1), and recognizes the voltage applied to LED module 13,14. The control unit 10 feedback-controls the lighting current of the recognized LED modules 13 and 14 to the target value by changing the ratio of the ON time to the driving cycle of the FET 5, that is, the ON duty ratio, or the driving frequency. 13 and 14 are lit at the target brightness. When the recognized lighting current of the LED modules 13 and 14 is insufficient with respect to the target value, the control unit 10 increases the on-duty ratio or decreases the drive frequency (both may be simultaneously). On the other hand, when the recognized lighting current of the LED modules 13 and 14 is larger than the target value, the control unit 10 decreases the on-duty ratio or increases the drive frequency (both can be simultaneously).

  The control unit 10 performs digital control using a microcomputer having a high-speed calculation function, analog control using an error amplifier circuit composed of an operational amplifier or the like, or digital-analog control combining a general-purpose microcomputer and an error amplifier circuit. Etc.

  When the control unit 10 turns on the FET 5, energy is stored in the transformer 4, and when the FET 5 is turned off, energy stored in the transformer 4 is transferred to the load side (smoothing capacitor 7, current detection resistor 8, LED) via the rectifier diode 6. To the modules 13, 14 and the cooling device 15). The smoothing capacitor 7 serves to suppress and smooth the pulsation of the lighting current of the LED modules 13 and 14.

  The power control circuit 16 built in the cooling device 15 receives the lighting current supplied from the LED lighting device 12 to the LED modules 13 and 14 and supplies the optimum power for driving the cooling fan 17. The cooling fan 17 includes a fan and a motor, and the motor rotates the fan by electric power supplied from the power control circuit 16 to cool the LED modules 13 and 14. Thereby, the temperature rise by the self-heating of the LED modules 13 and 14 is prevented, and the lifetime is suppressed.

  As described above, according to the first embodiment, the cooling device 15 is connected in series with the LED modules 13 and 14 between the outputs of the LED lighting device 12 which is a constant current power source, and operates by the motor to operate the LED modules 13 and 14. A cooling fan 17 that cools the LED module 13, and a first current energized from the LED lighting device 12 to the LED modules 13 and 14 is converted into a second current or a desired voltage that is different from the first current. And a power control circuit 16 to be supplied to the device. Therefore, even if the specifications of the LED modules 13 and 14 change and the lighting current may be different from the rated current of the cooling fan 17, one type of cooling device 15 can cope with it. Moreover, by incorporating the power control circuit 16 in the cooling device 15, the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

The power control circuit 16 built in the cooling device 15 can be configured as an independent power supply device.
Moreover, this power supply device is applicable to uses other than the cooling device of a vehicle-mounted lamp. For example, if an incandescent bulb is connected as the second load, the LED and the incandescent bulb can be turned on simultaneously by the LED lighting device.
Moreover, although the structure which uses LED (light emitting diode) as a semiconductor light source was shown in the said structure, the light source to light may be semiconductor light sources other than LED, such as LD (laser diode).

Embodiment 2. FIG.
FIG. 2 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the second embodiment is applied. 2 that are the same as or equivalent to those in FIG.
The cooling device 15 according to the second embodiment incorporates a second DC / DC converter 18 (power supply device). The second DC / DC converter 18 generates optimum power for the cooling fan 17 from the lighting current of the LED modules 13 and 14. The LED modules 13 and 14 and the cooling device 15 need only be connected in series, and the connection order is not limited.

  As described above, according to the second embodiment, the cooling device 15 uses the second current different from the first current or the desired current as the first current supplied from the LED lighting device 12 to the LED modules 13 and 14. The second DC / DC converter 18 is supplied to the cooling fan 17 after being converted to the above voltage. Therefore, similarly to the first embodiment, even if the specifications of the LED modules 13 and 14 are changed and the lighting current is different from the rated current of the cooling fan 17, one type of cooling device 15 can cope with it. Further, by incorporating the second DC / DC converter 18 in the cooling device 15, the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

Embodiment 3 FIG.
FIG. 3 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to Embodiment 3 is applied. In FIG. 3, the same or corresponding parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
In the third embodiment, a step-up converter is used for the second DC / DC converter 18. This is a configuration adopted when the lighting current of the LED modules 13 and 14 is equal to or larger than the rated current of the cooling fan 17. The step-up type second DC / DC converter 18 boosts the cooling fan 17 by boosting the voltage applied to the capacitor 19 to the driving voltage of the cooling fan 17 at which the current flowing through the cooling fan 17 becomes the rated current. Drive at the rated current (second current) and rated voltage. The LED modules 13 and 14 and the cooling device 15 need only be connected in series, and there is no restriction on the connection order.

FIG. 4 is a graph schematically showing the current and voltage of the cooling device 15 according to the third embodiment. 4A shows the on / off state of the FET ₂₁ , FIG. 4B shows the current I _{20 of the} coil ₂₀ , FIG. 4C shows the current I ₂₁ of the FET ₂₁ , and FIG. 4D shows the current I of the rectifier diode 22. ₂₂ , FIG. 4E shows the driving current I ₁₇ of the cooling fan 17, and FIG. 4F shows the voltage V ₂₃ of the capacitor ₂₃ and the voltage V _{19 of the} capacitor 19. For comparison, the rated currents Ir ₁₃ and 14 of the LED modules ₁₃ and ₁₄ and the rated current Ir ₁₇ of the cooling fan ₁₇ are shown as appropriate.

As shown in FIG. 4 (e), the in-vehicle lamp of the third embodiment has the lighting current of the LED modules 13 and 14 ≧ the driving current I ₁₇ of the cooling fan ₁₇ (the rated current Ir _{13,14 of the} LED modules 13 and ₁₄ ≧ This is the rated current Ir ₁₇ ) of the cooling fan 17. By using the step-up type second DC / DC converter 18 there, as shown in FIG. 4 (f), the voltage V _{23 of the} capacitor ₂₃ ≧ the voltage V _{19 of the} capacitor ₁₉ and the cooling fan 17 is set to the rated current and Drive at the rated voltage.

  The control unit 24 detects the voltage applied to the cooling fan 17 (the voltage at point B in FIG. 3), and changes the ratio of the ON time to the driving cycle of the FET 21, that is, the ON duty ratio, or the driving frequency. The feedback voltage of the cooling fan 17 is controlled to the target value.

The control unit 24 is configured by digital control, analog control, digital-analog control, or the like, like the control unit 10. When the applied voltage of the cooling fan 17 is insufficient with respect to the target value, the control unit 24 decreases the on-duty ratio or increases the drive frequency (both can be simultaneously). On the contrary, when the applied voltage of the cooling fan 17 is higher than the target value, the on-duty ratio is increased or the drive frequency is decreased (both can be simultaneously).
By the way, in the control of the second DC / DC converter 18 of the power supply apparatus using a current source as a power source, when the output power is increased, the on-duty of the switching elements (FETs 21 and 25) is reduced or the driving frequency is increased. When the output power is decreased by increasing the on-duty, the on-duty is increased or the drive frequency is decreased. That is, the on-duty enlargement / reduction, or the change direction of the increase / decrease of the drive frequency when the converter using the current source as the power source increases / decreases the output depends on the converter using the voltage source (for example, the first The direction of change is reversed with respect to the DC / DC converter 3).

  When the control unit 24 turns on the FET 21, current is supplied to the load side (capacitor 23 and cooling fan 17) via the rectifier diode 22 while storing energy in the coil 20, and by turning off the FET 21, the coil 20 is turned on. The energy stored in is discharged to the load side via the rectifier diode 22. The capacitor 23 serves to suppress and smooth the pulsation of the voltage applied to the cooling fan 17. Further, the capacitor 19 serves to suppress and smooth the pulsation of the lighting current of the LED modules 13 and 14.

  As described above, according to the third embodiment, since the step-up converter is used for the second DC / DC converter 18, the lighting current of the LED modules 13 and 14 is equal to the rated current of the cooling fan 17, or When the size is large, one type of cooling device 15 can cope with it. As in the first embodiment, the second DC / DC converter 18 is built in the cooling device 15 so that the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be provided. Can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

Embodiment 4 FIG.
FIG. 5 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the fourth embodiment is applied. 5 that are the same as or equivalent to those in FIGS. 1 to 4 are denoted by the same reference numerals and description thereof is omitted.
In the fourth embodiment, a step-down converter is used for the second DC / DC converter 18. This is a configuration adopted when the lighting current of the LED modules 13 and 14 is equal to or smaller than the rated current of the cooling fan 17. The step-down second DC / DC converter 18 steps down the cooling fan 17 by reducing the voltage applied to the capacitor 19 to the driving voltage of the cooling fan 17 at which the current flowing through the cooling fan 17 becomes the rated current. Drive at rated current and voltage. The LED modules 13 and 14 and the cooling device 15 need only be connected in series, and there is no restriction on the connection order.

FIG. 6 is a graph schematically showing the current and voltage of the cooling device 15 according to the fourth embodiment. 6A shows the on / off state of the FET 25, FIG. 6B shows the current I _{27 of the} coil ₂₇ , FIG. 6C shows the current I ₂₅ of the FET ₂₅ , and FIG. 6D shows the current I _{26 of the} diode _26. 6E shows the driving current I ₁₇ of the cooling fan 17, and FIG. 6F shows the voltage V ₁₉ of the capacitor ₁₉ and the voltage V _{23 of the} capacitor 23. For comparison, the rated currents Ir ₁₃ and 14 of the LED modules ₁₃ and ₁₄ and the rated current Ir ₁₇ of the cooling fan ₁₇ are shown as appropriate.

As shown in FIG. 6 (e), the in-vehicle lamp of the fourth embodiment has a driving current I ₁₇ of the cooling fan ₁₇ ≧ the lighting current of the LED modules 13 and 14 (the rated current Ir ₁₇ of the cooling fan ₁₇ ≧ the LED module 13, 14 rated currents Ir _13,14 ). By using the step-down type second DC / DC converter 18 there, the voltage V _{19 of the} capacitor 19 is equal to or higher than the voltage V _{23 of the} capacitor 23 as shown in FIG. Drive at the rated voltage.

  In the step-down type second DC / DC converter 18, when the control unit 24 turns on the FET 25, current is supplied to the load side (capacitor 23 and cooling fan 17) while storing energy in the coil 27. By turning off, the energy stored in the coil 27 is released to the load side via the rectifier diode 26. The capacitor 23 serves to suppress and smooth the pulsation of the voltage applied to the cooling fan 17. Further, the capacitor 19 serves to suppress and smooth the pulsation of the lighting current of the LED modules 13 and 14.

  As described above, according to the fourth embodiment, since the step-down converter is used for the second DC / DC converter 18, the lighting current of the LED modules 13 and 14 is equal to the rated current of the cooling fan 17, or When the size is small, one type of cooling device 15 can cope with it. As in the first embodiment, the second DC / DC converter 18 is built in the cooling device 15 so that the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be provided. Can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

  In the fourth embodiment, a coil (not shown) of the motor included in the cooling fan 17 can also be used without newly providing the coil 27 of the second DC / DC converter 18.

Embodiment 5. FIG.
FIG. 7 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the fifth embodiment is applied. In FIG. 7, the same or corresponding parts as those in FIGS. 1 to 6 are denoted by the same reference numerals and description thereof is omitted.
In the fifth embodiment, a converter that uses both a step-up converter and a step-down converter is used as the second DC / DC converter 18. This is a configuration in which the cooling fan 17 can be driven at the rated current and the rated voltage regardless of the magnitude relationship between the lighting current of the LED modules 13 and 14 and the rated current of the cooling fan 17. The LED modules 13 and 14 and the cooling device 15 need only be connected in series, and there is no restriction on the connection order.

8 and 9 are graphs schematically showing the current and voltage of the cooling device 15 according to the fifth embodiment. 8A and 9A are on / off states of the FETs ₂₁ and ₂₅ , FIG. 8B is a current I _{28 of the} coil ₂₈ , FIG. 8C is a current I ₂₁ of the FET ₂₁ , and FIG. ) Is the current I ₂₂ of the rectifier diode 22, FIGS. 8 (e) and 9 (e) are the drive current I ₁₇ of the cooling fan ₁₇ , and FIGS. 8 (f) and 9 (f) are the voltage V _{23 of the} capacitor 23. The voltage V _{19 of the} capacitor 19 is shown. 9B shows the current I _{28 of the} coil 28, FIG. 9C shows the current I ₂₅ of the FET ₂₅ , and FIG. 9D shows the current I _{26 of the} diode 26. For comparison, the rated currents Ir ₁₃ and 14 of the LED modules ₁₃ and ₁₄ and the rated current Ir ₁₇ of the cooling fan ₁₇ are shown as appropriate.

  The control unit 24 detects the voltage applied to the cooling fan 17 and changes the ratio of the ON time with respect to the driving cycle of the FET 21 or FET 25, that is, the ON duty ratio, or the driving frequency, thereby changing the applied voltage of the cooling fan 17. Is feedback controlled to the target value.

  When the lighting current of the LED modules 13 and 14 is larger than the rated current of the cooling fan 17, the control unit 24 always turns on the FET 25 and switches the FET 21 as shown in FIG. On the other hand, when the lighting current of the LED modules 13 and 14 is smaller than the rated current of the cooling fan 17, the control unit 24 always turns off the FET 21 and switches the FET 25 as shown in FIG. When the lighting current of the LED modules 13 and 14 is equal to the rated current of the cooling fan 17, the control unit 24 always turns the FET 25 on and the FET 21 always turns off.

  As described above, according to the fifth embodiment, since the second DC / DC converter 18 is configured to use a converter that serves both as a step-up converter and a step-down converter, the lighting current of the LED modules 13 and 14 and the cooling fan Regardless of the magnitude relationship with the 17 rated currents, one type of cooling device 15 can be used. As in the first embodiment, the second DC / DC converter 18 is built in the cooling device 15 so that the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be provided. Can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

Embodiment 6 FIG.
FIG. 10 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the sixth embodiment is applied. In FIG. 10, the same or corresponding parts as those in FIGS. 1 to 9 are denoted by the same reference numerals and description thereof is omitted.
In the sixth embodiment, a current detection resistor 30 is provided inside the cooling device 15 and the cooling fan 17 is driven with a rated current. In this example, a step-up converter and step-down converter combined second DC / DC converter 18 is used as in the fifth embodiment. Moreover, the LED modules 13 and 14 and the cooling device 15 should just be connected even in series, and there is no restriction | limiting in a connection order.

  The control unit 29 detects the voltage of the current detection resistor 30, that is, the driving current of the cooling fan 17, and changes the ratio of the ON time to the driving cycle of the FET 21 or FET 25, that is, the ON duty ratio, or the driving frequency. The drive current of the cooling fan 17 is feedback controlled to the target value. Since the motor resistance of the cooling fan 17 is a known value, even if the cooling fan 17 is driven by constant current control, a constant power operation is performed.

The control unit 29 is configured by digital control, analog control, digital-analog control, or the like, similarly to the control unit 10 and the control unit 24.
The current and voltage of the cooling device 15 of the sixth embodiment are the same as in the graph of FIG.

  The control unit 29 detects the driving current of the cooling fan 17 using the current detection resistor 30, and also detects the voltage applied to the cooling fan 17 (the voltage at point B in FIG. 10), and the detected driving current. When the constant power control is performed based on the applied current, it is possible to eliminate the influence of the variation and fluctuation of the motor resistance of the cooling fan 17 and realize more stable driving of the cooling fan 17.

  As described above, according to the sixth embodiment, even when the cooling device 15 is provided with a current detection resistor and the cooling fan 17 is driven by constant current control, the lighting current of the LED modules 13 and 14 and the cooling fan Since it can be used regardless of the magnitude relationship with the rated current of 17, even if the specifications of the LED modules 13 and 14 change, one type of cooling device 15 can cope. As in the first embodiment, the second DC / DC converter 18 is built in the cooling device 15 so that the LED modules 13 and 14 and the cooling device 15 can be connected in series, and wiring dedicated to the cooling device can be provided. Can be omitted. Furthermore, the cooling device 15 can be connected to any position of the LED modules 13 and 14.

Embodiment 7 FIG.
FIG. 11 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the seventh embodiment is applied. In FIG. 11, the same or corresponding parts as those in FIGS. 1 to 10 are denoted by the same reference numerals and description thereof is omitted.
In the seventh embodiment, the temperature sensor 31 is installed in the LED module 13. The power control circuit 16 of the cooling device 15 includes a temperature detection unit 32 and a control unit 33. The temperature detector 32 detects the temperature measured by the temperature sensor 31. The control unit 33 operates the cooling fan 17 when the temperature detected by the temperature detection unit 32 is equal to or higher than a preset threshold so that the LED modules 13 and 14 are not thermally destroyed. When the temperature detected by the temperature detection unit 32 is less than the preset threshold value, the control unit 33 stops the operation of the cooling fan 17.
The preset threshold value is 85 ° C., for example.

  As described above, according to the seventh embodiment, the cooling device 15 cools when the temperature detection unit 32 that detects the temperature of the LED modules 13 and 14 and the temperature detected by the temperature detection unit 32 is equal to or higher than a preset threshold value. The control unit 33 that operates the fan 17 is provided. Therefore, it is possible to stop the cooling fan 17 in a low temperature region where cooling is not necessary, extend the life of the cooling fan, and suppress power consumption.

Embodiment 8 FIG.
FIG. 12 is a circuit diagram illustrating a configuration example of an in-vehicle lamp to which the cooling device 15 according to the eighth embodiment is applied. In FIG. 12, the same or corresponding parts as those in FIGS. 1 to 11 are denoted by the same reference numerals and description thereof is omitted.
In the eighth embodiment, an example in which the motor of the cooling fan 17 is a brushless motor will be described. As shown in FIG. 12, the brushless motor includes a three-phase coil 17a and three sensors 17b that detect the phase of the rotor. The three-phase coil 17a is connected to the capacitor 41 via six transistors 46-51. The diodes 52 to 54 are reflux diodes.

  FIG. 13 is a graph schematically showing a driving sequence of the brushless motor included in the cooling device 15 according to the eighth embodiment. 13A shows a PWM operation output from the control unit 42 to each of the NAND circuits 43 to 45, FIG. 13B shows an on / off operation output from the control unit 42 to the NAND circuit 43, and FIG. 13C shows a control. ON / OFF operation output from the unit 42 to the NAND circuit 44, FIG. 13D shows an ON / OFF operation output from the control unit 42 to the NAND circuit 45, FIG. 13E shows an ON / OFF state of the transistor 46, and FIG. 13 (f) is an on / off state of the transistor 47, FIG. 13 (g) is an on / off state of the transistor 48, FIG. 13 (h) is an on / off state of the transistor 49, and FIG. ON / OFF state, FIG. 13J shows the ON / OFF state of the transistor 51. The horizontal axis of each graph is the rotor phase.

  As shown in FIGS. 13A to 13G, the transistors 46 to 48 are switched in accordance with a negative logical product operation result of the PWM operation output and the on / off operation output by the NAND circuits 43 to 45. The control unit 42 performs PWM operation output and on / off operation output according to the signals of the three sensors 17b, and sequentially switches the transistors 46 to 51, thereby changing the direction of the current flowing through the three-phase coil 17a. The rotor is rotated by changing the direction of the magnetic flux. At that time, the control unit 42 detects the voltage of the current detection resistor 30, that is, the driving current of the cooling fan 17, and controls the switching of the transistors 46 to 48 by changing the on-duty ratio of the PWM operation output. The drive current of the cooling fan 17 is feedback controlled to the target value.

  As described above, according to the eighth embodiment, the cooling device 15 detects the current supplied to the brushless motor, the current detection resistor 30, and the second current based on the current detected using the current detection resistor 30. The control unit 42 performs both constant current control that converts the current into the current and supplies it to the brushless motor, and drive control of the brushless motor. Therefore, one control unit 42 can be used both for driving the brushless motor of the cooling fan 17 and for controlling the constant current, and the cooling device 15 can be reduced in size and cost.

  In the present invention, within the scope of the invention, any combination of each embodiment, any component of each embodiment can be modified, or any component of each embodiment can be omitted.

  DESCRIPTION OF SYMBOLS 1 In-vehicle power supply (in-vehicle battery), 2 switch, 3 1st DC / DC converter part, 4 transformer, 5 FET, 6 Rectifier diode, 7 Smoothing capacitor, 8 Current detection resistor, 9 Control power supply part, 10 Control part, 11 Inverting amplifier, 12 LED lighting device (constant current power supply), 13, 14 LED module (first load), 15 cooling device (second load), 16 power control circuit (power supply device), 17 cooling fan, 17a coil , 17b sensor, 18 second DC / DC converter (power supply device), 19 capacitor, 20 coil, 21 FET, 22 rectifier diode, 23 capacitor, 24 control unit, 25 FET, 26 rectifier diode, 27 coil, 28 coil, 29 control unit, 30 current detection resistor, 31 temperature sensor, 32 temperature detection unit, 33 Control unit, 41 a capacitor, 42 control unit, 43 to 45 NAND circuit, 46 to 51 transistors, 52 to 54 diode.

Claims (13)

A power supply device connected in series with a first load between outputs of a constant current power source that outputs a first current,
A first current supplied from the constant current power source to the first load is converted into a second current or a desired voltage different from the first current, and is connected to the output side of the power supply device. A power supply device that supplies power to two loads.   The power supply apparatus according to claim 1, further comprising a DC / DC converter that converts the first current into the second current or a desired voltage.   3. The power supply device according to claim 2, wherein the DC / DC converter is a step-up converter, a step-down converter, or a converter that serves as both.   The power supply device according to claim 2 or 3, further comprising a control unit that detects a voltage supplied to the second load and controls the DC / DC converter at a constant voltage based on the detected voltage. Power supply.   The power supply apparatus according to claim 2 or 3, further comprising a control unit that detects a current supplied to the second load and performs constant current control on the DC / DC converter based on the detected current. Power supply.   The power supply device according to claim 1, wherein the first load is a semiconductor light source. The power supply device according to claim 1, wherein the second load is a motor that operates a cooling fan,
A power supply apparatus comprising a control unit for driving the motor. The power supply device according to claim 1, wherein the second load is a brushless motor that operates a cooling fan,
A power supply apparatus comprising a control unit for driving the brushless motor. The power supply device according to claim 7 or 8, further comprising a temperature detection unit that detects a temperature of the first load,
The said control part operates the said cooling fan when the temperature detected by the said temperature detection part is more than the preset threshold value, The power supply device characterized by the above-mentioned.   The power supply device according to claim 1, wherein the power supply device includes the constant current power source configured by a DC / DC converter using a vehicle battery as a power source, and receives the current output from the constant current power source. apparatus. A cooling device connected in series with the semiconductor light source between outputs of a constant current power source that outputs a first current for lighting the semiconductor light source,
A motor for operating a fan for cooling the semiconductor light source;
A cooling device comprising: a control circuit that converts the first current into a second current different from the first current or a desired voltage and drives the motor. A semiconductor light source lighting device for lighting a semiconductor light source provided in a lamp,
A constant current power supply unit that generates and outputs a first current for lighting the semiconductor light source from a power supply;
A cooling unit connected in series with the semiconductor light source between the outputs of the constant current power supply unit,
The cooling unit includes a motor that operates a fan that cools the semiconductor light source;
A semiconductor light source lighting device comprising: a control circuit that converts the first current into a second current different from the first current or a desired voltage and drives the motor.   13. The semiconductor light source lighting device according to claim 12, wherein the semiconductor light source lighting device uses an in-vehicle battery as the power source, and lights the semiconductor light source included in the lamp mounted on the vehicle.

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