Light source lighting circuit and turn signal lamp

• US 9,974,128 B2
• Filed: 12/16/2015
• Issued: 05/15/2018
• Est. Priority Date: 12/24/2014
• Status: Active Grant

• Current Assignee: Koito Manufacturing Company Limited
• Original Assignee: Koito Manufacturing Company Limited
• Inventors: Ohta, Shinji, Sawada, Masahiro
• Primary Examiner(s): PHAM, THAI N
• Application Number:
  US15/539,237
• Publication Number:
  US 20170359869A1
• Time in Patent Office: 881 Days
• CPC Class Codes: B60Q 1/34 for indicating change of drive direction B60Q1/22 takes precedence
• CPC Class Codes: B60Q 1/382 Electronic temporisation with semiconductor amplification
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• CPC Class Codes: H05B 45/50 responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
• CPC Class Codes: H05B 47/10 Controlling the light source
• CPC Class Codes: H05B 47/24 Circuit arrangements for protecting against overvoltage
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A light source lighting circuit comprises a first lighting circuit for receiving current from the electric power supply line and supplying drive current to a first light source and a second lighting circuit for receiving the current from the electric power supply line and supplying drive current to a second light source. When a state of the drive current flowing to the first light source shows an abnormality, or when state of the drive current flowing to the second light source shows an abnormality, the first lighting circuit stops operation. When a state of the drive current flowing to the second light source shows an abnormality, or when a state of the drive current flowing to the first light source shows an abnormality, the second lighting circuit stops operation.

Claims

1. A light source lighting circuit comprising:

a first lighting circuit having a first light emission driving circuit configured to receive current from an electric power supply line and to supply drive current to a first light source, and

a second lighting circuit having a second light emission driving circuit configured to receive current from the electric power supply line and to supply drive current to a second light source,

wherein the first lighting circuit is configured to generate a first state signal corresponding to a state of the drive current flowing to the first light source and to output a second notification signal corresponding to the first state signal to the second lighting circuit,

wherein the second lighting circuit is configured to generate a second state signal corresponding to a state of the drive current flowing to the second light source and to output a first notification signal corresponding to the second state signal to the first lighting circuit,

wherein when the first state signal indicates an abnormality or when the first notification signal indicates an abnormality, the first lighting circuit stops operation thereof, and

wherein when the second state signal indicates an abnormality or when the second notification signal indicates an abnormality, the second lighting circuit stops operation thereof.

2. The light source lighting circuit according to claim 1, wherein the first lighting circuit comprises a current consuming unit configured to consume a part of the electric power to be supplied from the electric power supply line and to enable regulating current to flow, and lowers a current value of the regulating current when the first state signal indicates an abnormality or when the first notification signal indicates an abnormality.

3. A turn signal lamp comprising:

a first lamp unit attached to a door part provided to be freely openable and closable for a vehicle main body part at a rear end portion of a vehicle, and

a second lamp unit attached to the vehicle main body part-side and positioned at an outermore side than the first lamp unit in a width direction of the vehicle,

wherein the first lamp unit comprises a first light emitting unit and the first lighting circuit of claim 1, and

wherein the second lamp unit comprises a second light emitting unit and the second lighting circuit of claim 1.

12. The light source lighting circuit according to one of claim 1, wherein the first lighting circuit comprises a first DC/DC converter having a first switching element, and

wherein the second lighting circuit comprises a second DC/DC converter having a second switching element.

4. A light source lighting circuit comprising:

a first lighting circuit having a first light emission driving circuit configured to turn on a plurality of light sources of a first light emitting unit on the basis of an input voltage, and

a second lighting circuit having a second light emission driving circuit configured to turn on a light source of a second light emitting unit on the basis of an input voltage,

wherein the first lighting circuit having a sequential circuit configured;

to sequentially turn on the light sources of the first light emitting unit in accordance with a timing signal, and

to output the timing signal to the second lighting circuit, and

wherein the second lighting circuit is configured to start lighting of the light source of the second light emitting unit in accordance with the timing signal.

5. The light source lighting circuit according to claim 4, wherein the second light emitting unit comprises a plurality of light sources, and

wherein the second lighting circuit is configured to start sequential lighting of the light sources of the second light emitting unit in accordance with the timing signal.

6. The light source lighting circuit according to claim 4, wherein the first lighting circuit and the second lighting circuit are configured to turn on the corresponding light sources by receiving current from a common electric power supply line,

wherein the first lighting circuit is configured to generate a state signal corresponding to a state of drive current flowing to the light sources of the first light emitting unit and to output a notification signal corresponding to the state signal to the second lighting circuit,

wherein the second lighting circuit stops operation thereof or lowers a current value of regulating current flowing to a current consuming unit configured to consume a part of electric power to be supplied from the electric power supply line when the notification signal indicates an abnormality, and

wherein the first lighting circuit is configured to output the timing signal through an output line of the notification signal.

7. A turn signal lamp comprising:

a first lamp unit attached to a door part provided to be freely openable and closable for a vehicle main body part at a rear end portion of a vehicle, and

a second lamp unit attached to the vehicle main body part-side and positioned at an outermore side than the first lamp unit in a width direction of the vehicle

wherein the first lamp unit comprises the first lighting circuit and the first light emitting unit according to claim 4, and

wherein the second lamp unit comprises the second lighting circuit and the second light emitting unit according to claim 4.

8. A light source lighting circuit comprising:

a first lighting circuit having a first light emission driving circuit configured to receive current from an electric power supply line and to supply drive current to a first light source;

a second lighting circuit having a first light emission driving circuit configured to receive current from the electric power supply line and to supply drive current to a second light source, and

a first current consuming unit provided for the first lighting circuit and configured to consume a part of the electric power to be supplied from the electric power supply line and to enable first regulating current to flow,

wherein the first lighting circuit is configured to generate a first state signal corresponding to a state of the drive current flowing to the first light source,

wherein the second lighting circuit is configured to generate a second state signal corresponding to a state of the drive current flowing to the second light source and to output a first notification signal corresponding to the second state signal to the first lighting circuit, and

wherein when the first state signal indicates an abnormality or when the first notification signal indicates an abnormality, the first lighting circuit lowers a current value of the first regulating current.

9. The light source lighting circuit according to claim 8, wherein the light source lighting circuit keeps the first lighting circuit at a state where a light emission driving of the first light source is possible when the first state signal does not indicate an abnormality even though the first notification signal indicates an abnormality.

10. The light source lighting circuit according to claim 8 wherein only the first current consuming unit is provided as a current consuming unit.

11. The light source lighting circuit according to claim 8, further comprising a second current consuming unit provided for the second lighting circuit and configured to consume a part of the electric power to be supplied from the electric power supply line and to enable second regulating current to flow,

wherein the first lighting circuit is configured to output a second notification signal corresponding to the first state signal to the second lighting circuit, and

wherein when the second state signal indicates an abnormality or when the second notification signal indicates an abnormality, the second lighting circuit lowers a current value of the second regulating current.

13. A turn signal lamp comprising:

a first lamp unit attached to a door part provided to be freely openable and closable for a vehicle main body part at a rear end portion of a vehicle, and

a second lamp unit attached to the vehicle main body part-side and positioned at an outermore side than the first lamp unit in a width direction of the vehicle,

wherein the first lamp unit comprises a first light emitting unit and the first lighting circuit of claim 8, and

wherein the second lamp unit comprises a second light emitting unit and the second lighting circuit of claim 8.

14. A light source lighting circuit provided for a pair of lamps of which electric power supply from a vehicle-side is individually controlled, the light source lighting circuit comprising:

a lighting circuit having a light emission driving circuit configured to enable drive current to flow to a light source on the basis of the electric power to be supplied from the vehicle-side;

a current consuming unit configured to consume a part of the electric power to be supplied from the vehicle-side and to enable regulating current to flow, and

a current regulation circuit configured to receive a drive state signal corresponding to a state of the drive current and a mode signal indicative of a lighting/lights-out state of the other lamp from the other lamp and to lower a current value of the regulating current in each of a case where the drive state signal indicates an abnormality and a case where the mode signal indicates a lighting state.

15. The light source lighting circuit according to claim 14, wherein the current regulation circuit is configured to use the mode signal for regulation of the regulating current via an insulation-type signal transmission element.

16. A turn signal lamp comprising the light source lighting circuit and the light sources according to claim 14, wherein the light source lighting circuit is configured to branch a power supply voltage to be supplied from the vehicle-side and to output the same to the other lamp, as a mode signal indicative of a lighting/lights-out state of the lamp.