JP5778512B2 - Control device for vehicle lamp - Google Patents

Description

  The present invention relates to a control device that controls lighting of a lamp mounted on a vehicle, and more particularly to a technique for limiting a voltage supplied to the lamp.

  Each lamp such as a brake lamp, a tail lamp, and a head lamp mounted on the vehicle is turned on when power is supplied from a battery mounted on the vehicle. Further, the output voltage of the battery is not always a constant value, but varies according to the running state of the vehicle. For example, the battery voltage has a high value when traveling on an expressway.

  Here, the lifetime of each lamp described above is shortened when a voltage higher than a normal operating voltage is supplied. For example, a lamp that operates at a battery voltage of 13.5 V, which is a normal battery voltage, has a lamp life shortened to about 1/3 when the battery voltage rises to about 16 V.

  Therefore, in order to keep the voltage supplied to each lamp at a constant value even when the battery voltage rises, a switching element such as an FET is installed on the wiring connecting the battery and the lamp, and the switching element is set to a desired duty. It has been proposed to reduce the supply voltage by PWM control with a ratio (see, for example, Patent Document 1).

  Hereinafter, a conventional control device will be described with reference to a circuit diagram shown in FIG. FIG. 9 shows a circuit for reducing the voltage supplied to the tail lamps 14R, 14L on the right side and the left side (right side, left side in the vehicle traveling direction) and the brake lamps 15R, 15L on the right side and the left side mounted on the rear of the vehicle. Yes.

  As shown in the figure, this control circuit has three branch lines branching from a common bus connected to the battery VB. The first branch line is a switching element such as a relay 11, a fuse Fu1, and an FET. The tail lamps 14R and 14L are connected to one end via T11, and the other end is grounded. When the light switch 12 is operated, the relay coil 11c is excited, the relay contact 11s is turned on, voltage is supplied to the tail lamps 14R and 14L, and the tail lamps 14R and 14L are lit. The fuse Fu2 is connected to an electrical component other than the tail lamps 14R and 14L (not shown) (for example, an indoor lamp indicating that the tail lamps 14R and 14L are lit).

  The second branch line is connected to one end of the brake lamps 15R and 15L via the switch 13 and the switch element T12, and the other end is grounded. When the switch 13 is turned on, a voltage is supplied to the brake lamps 15R and 15L, and the brake lamps 15R and 15L are lit.

  Further, the third branch line is connected to one end of the heater 52 via the switch 51, and the other end is grounded. When the switch 51 is turned on, a voltage is supplied to the heater 52 and the heater 52 generates heat.

  Further, in order to reduce the voltage supplied to the tail lamps 14R, 14L, the control unit 53 is connected to the control terminal of the switch element T11. When the voltage of the battery VB is high, the switch element T11 is set at a desired duty ratio. The voltage supplied to the tail lamps 14R and 14L is reduced by PWM control.

  Further, in order to reduce the voltage supplied to the brake lamps 15R and 15L, the control unit 54 is connected to the control terminal of the switch element T12. When the voltage of the battery VB is high, the switch element T12 is set to a desired duty ratio. The voltage supplied to the brake lamps 15R and 15L is reduced by PWM control.

  In such a conventional control device, it is necessary to provide two switch elements T11 and T12 and two control units 53 and 54 in order to adjust the voltages supplied to the tail lamps 14R and 14L and the brake lamps 15R and 15L. There arises a problem that the apparatus configuration becomes large-scale. Therefore, in order to use the control units 53 and 54 in common, if a switch element is provided on the common bus to perform PWM control, the heater 52 that does not require PWM control and the tail lamps 14R and 14L connected to the fuse Fu2 are used. There is a problem that even the electrical components are PWM-controlled.

JP 2004-355887 A

  As described above, in the conventional vehicle lamp control device, when PWM control is performed for the purpose of reducing the voltage supplied to the lamp, it is necessary to mount a plurality of switch elements and a control unit. However, there has been a problem in that the size of the apparatus is increased and the cost is increased.

  The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a vehicle lamp control device capable of reducing the voltage supplied to the lamp with a simple configuration. Is to provide.

In order to achieve the above object, according to the first aspect of the present invention, there is provided a vehicular lamp control device for controlling lighting of a plurality of lamps mounted on a vehicle, wherein one end of each lamp is a switch means (11, 13). ), The other end is connected to the ground side, and a switch element (T1) provided between the point connecting the other ends of the at least two lamps and the ground. PWM control means (17) for PWM-controlling the switch element with a desired duty ratio , and further comprising a first connector and a second connector detachably attached to the first connector, The control means and the electronic switch are mounted on the first connector, and the first connector has a connection part (32) connectable to a ground terminal (body) of the vehicle, and A first terminal group coupled to the WM control means; and the second connector includes a second terminal group to which the other ends of the at least two lamps are connected, and the second connector is attached to the first connector. In this case, the first terminal group and the second terminal group are electrically connected .

  The invention according to claim 2 further includes voltage detection means (17) for detecting a voltage supplied to the lamp, wherein the PWM control means is configured to detect the voltage according to the voltage detected by the voltage detection means. The duty ratio of PWM control is changed.

According to the first aspect of the present invention, a switch element is provided between each lamp and the ground, and the voltage supplied to each lamp is reduced by PWM control of the switch element at a desired duty ratio. Therefore, it is possible to perform PWM control of voltages supplied to a plurality of lamps with a single switch element, and it is possible to reduce the number of parts to be used and reduce the scale of the apparatus. In addition, since the first connector is connected to the ground terminal and the first connector and the second connector are mounted, various connection patterns can be selected by changing the configuration of the electrical circuit mounted on the first connector. The design can be changed with a simple operation.

  According to the second aspect of the invention, since the duty ratio when driving the switch element is changed according to the voltage detected by the voltage detecting means, the duty ratio is set according to the fluctuation of the voltage supplied from the power source. And a more stable voltage can be supplied to the lamp.

It is a circuit diagram which shows the structure of the lamp lighting circuit containing the control apparatus of the lamp | ramp for vehicles which concerns on one Embodiment of this invention. It is a circuit diagram which shows the structure of a lamp lighting circuit when not using the vehicle lamp control apparatus which concerns on one Embodiment of this invention. It is explanatory drawing which shows the circuit provided in the 1st connector of the control apparatus of the vehicle lamp which concerns on one Embodiment of this invention. It is explanatory drawing which shows the structure of the 1st connector used when not using the control apparatus of the vehicle lamp which concerns on one Embodiment of this invention. It is explanatory drawing which shows the structure of the 1st connector of the control apparatus of the vehicle lamp which concerns on one Embodiment of this invention. It is explanatory drawing which shows the mode of mounting | wearing of the 1st connector and 2nd connector of the control apparatus of the lamp | ramp for vehicles which concerns on one Embodiment of this invention. It is explanatory drawing which shows the internal structure of the 2nd connector of the control apparatus of the vehicle lamp which concerns on one Embodiment of this invention. It is a flowchart which shows the process sequence of the control apparatus of the vehicle lamp which concerns on one Embodiment of this invention. It is a circuit diagram which shows the structure of the conventional lamp lighting circuit.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a lamp lighting circuit including a vehicle lamp control device 16 (hereinafter simply referred to as “control device 16”) according to an embodiment of the present invention.

  As shown in FIG. 1, the output terminal of the battery (power source) VB mounted on the vehicle is branched into three systems, and the first branch line is the right side via the relay (switch means) 11 and the fuse Fu. The left tail lamps 14R and 14L are connected to one end, and the other end is connected to the control device 16. The relay 11 includes a relay coil 11c and a relay contact 11s. When the light switch 12 is turned on from an upstream device (not shown), the relay coil 11c is excited to conduct the relay contact 11s, and each tail lamp The output voltage of the battery VB is supplied to 14R and 14L. Moreover, one end side of each tail lamp 14R, 14L is connected to the control apparatus 16 via the electric wire n1.

  The second branch line is connected to one end of the brake lamps 15R and 15L via a switch (switch means) 13 and the other end is connected to the control device 16. When the switch 13 is turned on, the output voltage of the battery VB is supplied to the brake lamps 15R and 15L. One end side of each brake lamp 15R, 15L is connected to control device 16 via electric wire n2.

  The third branch line is connected to one end of the heater 52 via the switch 51, and the other end is grounded. When the switch 51 is turned on, a voltage is supplied to the heater 52 and the heater 52 generates heat.

  Next, a detailed configuration of the control device 16 will be described. As illustrated in FIG. 6, the control device 16 according to the present embodiment includes a first connector 41 and a second connector 42 that fits into the first connector 41.

  FIG. 3 is a configuration diagram showing a circuit board mounted inside the first connector 41. As shown in the figure, the first connector 41 is provided with a substrate 34 and a metal protrusion (connection portion) 32 connected to the substrate 34. An opening 33 is formed in the protrusion 32, and a screw can be inserted into the opening 33 and fastened to, for example, a vehicle body ground.

  The substrate 34 is mounted with a control unit 17 composed of an IC chip or the like, and a switch element T1 such as an FET. One end of the switch element T1 (for example, the source of the FET) is connected to the protrusion 32, The end (for example, the drain of the FET) branches into four systems and is connected to terminals 37a, 37b, 37c, and 37d (first terminal group), respectively. As will be described later, the four terminals 37a to 37d are connected to the tail lamps 14R and 14L and the brake lamps 15R and 15L via the second connector 42 when the second connector 42 is connected. The

  Further, the control unit 17 is connected to the control input terminal (for example, the gate of the FET) of the switch element T1, and performs PWM control of the switch element T1 with a desired duty ratio by a procedure described later. The control unit 17 is connected to terminals 37e and 37f (first terminal group). As will be described later, the terminals 37e and 37f are connected to the electric wires n1 and n2 shown in FIG. 1 through the second connector 42 when the second connector 42 is connected. And the control part 17 measures the voltage supplied to tail lamp 14R, 14L and brake lamp 15R, 15L based on the voltage which arises in electric wire n1, n2, and PWM-controls switch element T1 based on this voltage. . That is, the control unit 17 has a function as a voltage detection unit that detects a voltage supplied to the lamp, and also has a function as a PWM control unit that performs PWM control of the switch element T1 with a desired duty ratio.

  Further, as shown in FIG. 5, the entire substrate 34 is covered with the casing 35 to constitute the first connector 41 shown in FIG. 6. At this time, as shown in FIG. 5, the lower side of the casing 35 is an expanded portion 35 a, and the second connector 42 is inserted into the expanded portion 35 a to connect both the connectors 41 and 42. It will be.

  On the other hand, the 2nd connector 42 shown in FIG. 6 is provided with the terminals 44a-44f (2nd terminal group) connected with each terminal 37a-37f of the 1st connector 41, as shown in FIG. Further, an electric wire 43 is connected to each of the terminals 44a to 44f. By passing through the electric wires 43, the terminal 44a is connected to the right tail lamp 14R, the terminal 44b is connected to the left tail lamp 14L, the terminal 44c is connected to the right brake lamp 15R, and the terminal 44d is connected to the left tail lamp 14R. The brake lamp 15L is connected, the terminal 44e is connected to the electric wire n1, and the terminal 44f is connected to the electric wire n2.

  The control device 16 according to the present embodiment operates in a state where the second connector 42 is attached to the first connector 41 and the protrusion 32 is connected to the vehicle body earth. Hereinafter, the control procedure by the control part 17 is demonstrated with reference to the flowchart shown in FIG.

  First, in step S11, the control unit 17 determines whether or not the monitor voltage is equal to or higher than a preset threshold voltage. For example, if the threshold voltage is set to 13.5 V and the monitor voltage, that is, the monitor voltage detected via the electric wire n1 or the electric wire n2 is equal to or higher than the threshold voltage, the process proceeds to step S13, and the threshold voltage is set. If it is lower than the voltage, the process proceeds to step S12.

  In step S12, the control unit 17 performs PWM control of the switch element T1 with a duty ratio corresponding to the monitor voltage. For example, when the monitor voltage is 16 V, the duty ratio is set to 70% and PWM control is performed. As a result, the voltage supplied to each lamp 14R, 14L, 15R, 15L can be reduced to about the threshold voltage. Accordingly, it is possible to prevent an excessive voltage from being supplied to the lamps 14R, 14L, 15R, and 15L.

  In step S13, the control unit 17 controls the switch element T1 so as to be always on (duty ratio 100%). Accordingly, the lamps 14R, 14L, 15R, and 15L are supplied with a voltage lower than a threshold voltage (for example, 13.5 V) and are lit.

  In this manner, the vehicle lamp control device 16 according to the present embodiment monitors the voltages supplied to the tail lamps 14R and 14L and the brake lamps 15R and 15L, and the monitor voltage is a preset threshold voltage (for example, 13.5V), the switching element T1 provided between the lamps 14R, 14L, 15R, 15L and the body earth (ground) is PWM-controlled with a desired duty ratio, Reduce the voltage supplied to the lamp. Therefore, even when the output voltage of the battery VB fluctuates, the voltage supplied to each lamp 14R, 14L, 15R, 15L can be stabilized, and the problem that the lamp life is shortened can be solved. it can.

  In addition, one switch element T1 is provided for a plurality of lamps (four lamps 14R, 14L, 15R, 15L in the present embodiment), and the switch element T1 is PWM-controlled by the control unit 17 to the lamp. Therefore, it is not necessary to provide a plurality of switch elements as in the prior art. That is, the heater 52 shown in FIG. 1 is supplied with the output voltage of the battery VB without PWM control. By adopting the control device 16 according to this embodiment, only the circuit connected to the lamp is provided. PWM control can be performed. As a result, the apparatus configuration can be simplified as compared with the conventional case, and space saving and cost reduction can be achieved.

  Further, in the present embodiment, since the control device 16 includes the first connector 41 and the second connector 42, the first connector 41 can be replaced with a simple operation. That is, when PWM control is not required, the design can be easily changed by changing the board mounted in the first connector 41 to the board 34a having the entire conductor as shown in FIG. .

  The substrate 34a shown in FIG. 4 is entirely a conductor, and the terminals 37a to 37d are electrically connected to the conductor. Further, the terminals 37e and 37f are not connected to the conductor.

  Therefore, as shown in FIG. 5, when the casing 35 is covered with the substrate 34a shown in FIG. 4 to form the first connector 41, and the first connector 41 is connected to the second connector 42, the lamps 14R, 14L, The terminals on the ground side of 15R and 15L are connected to the vehicle body earth via terminals 37a to 37d. Moreover, since the electric wires n1 and n2 are connected to the terminals 37e and 37f, the tips thereof are in an open state. That is, since they are connected as in the circuit 21 shown in FIG. 2, the terminals of the lamps 14R, 14L, 15R, 15L can be grounded.

  That is, when the voltage fluctuation of the battery VB is large and the output voltage needs to be subjected to PWM control, the first connector 41 having the substrate 34 shown in FIG. 3 is used for connection, and when PWM control is not performed, By connecting using the first connector 41 having the board 34a shown in FIG. 4, it becomes possible to switch the circuit without changing the circuit on a large scale.

  In the above-described embodiment, the example in which the switch element T1 is PWM-controlled when the monitor voltage detected on one of the wires n1 and n2 is equal to or higher than the threshold voltage has been described. Only one of them may be routed, and the battery voltage may be monitored using this electric wire.

  As mentioned above, although the control apparatus of the vehicle lamp of this invention was demonstrated based on embodiment of illustration, this invention is not limited to this, The structure of each part is the thing of arbitrary structures which have the same function Can be replaced.

  For example, in the above-described embodiment, the control device 16 is provided between the terminals of the tail lamps 14R and 14L and the brake lamps 15R and 15L and the body ground to reduce the voltage, but other lamps, for example, It can also be used for back lamps, head lamps, and the like.

  Furthermore, in the embodiment described above, an example in which one switch element T1 is provided for four lamps has been described. However, the present invention is not limited to this, and one switch element T1 is provided for two or more lamps. This includes the case where a switch element is provided. Each lamp can also be constituted by an LED.

  The present invention can be used to reduce the voltage supplied to a lamp mounted on a vehicle.

T1 switch element VB battery n1, n2 electric wire 11 relay 11c relay coil 11s relay contact 12 light switch 13 switch 14R, 14L tail lamp 15R, 15L brake lamp 16 control device 17 control unit 32 protrusion 33 opening 34, 34a substrate 35 casing 35a Expanding part 41 First connector 42 Second connector 43 Electric wire

Claims (2)

In a vehicle lamp control device that controls lighting of a plurality of lamps mounted on a vehicle,
One end of each lamp is connected to the power supply through the switch means, the other end is connected to the ground side,
A switch element provided between a point connecting the other ends of the at least two lamps and a ground;
PWM control means for PWM controlling the switch element at a desired duty ratio;
With
Furthermore, it has a 1st connector and the 2nd connector which can be attached or detached with respect to this 1st connector,
The PWM control means and the switch element are mounted on the first connector,
The first connector has a connection portion connectable to a ground terminal of the vehicle, and includes a first terminal group coupled to the PWM control means,
The second connector includes a second terminal group to which the other ends of the at least two lamps are connected,
The control device for a vehicle lamp , wherein the first terminal group and the second terminal group are electrically connected when the second connector is attached to the first connector . Voltage detecting means for detecting a voltage supplied to the lamp;
2. The vehicle lamp control device according to claim 1, wherein the PWM control unit changes a duty ratio of the PWM control in accordance with a voltage detected by the voltage detection unit.

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