JPH0230896B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a control device for a single bulb (also referred to as a single filament valve) used as an automotive lamp, and particularly to a control device for a single filament (hereinafter referred to as a single filament). This invention relates to a single-valve control device that variably controls the illuminance level of each sign function in a single bulb that has light distribution characteristics according to the three sign functions of stop, tail, and parking by using reflected light from the vehicle. .

[Prior art]

Traditionally used as automotive lighting2
For valves with two filaments,
Because the two filaments installed in one bulb chamber are in different positions, the relative positions of each filament and the reflector and front lens tend to shift.
Light distribution characteristics tend to change slightly. Particularly in car body color lamps, if the light source position is shifted, the light will not be concentrated in the gap between the coatings between the lenses, causing a problem in which the luminous intensity will drop significantly.

For this reason, recently, single filament has been developed for stop, tail and parking.
A single valve with two marking functions has been proposed. This single bulb has a single filament placed at the focal point of a parabolic reflector, and the reflected light from this filament is emitted through a predetermined lens system, thereby supporting each stop, tail, and parking sign function. It is configured to have light distribution characteristics. A single bulb with such a structure has the advantage that the relative positions of the single filament, the reflective surface, and the lens system can be made accurate, the decrease in luminous intensity is small, and the bulb can be made compact. However, since the illuminance of each stop, tail, and parking area varies greatly depending on the purpose of use, a device for controlling the illuminance of these areas has been desired.

[Summary of the invention]

The present invention has been made in view of the above points, and its purpose is to control the illuminance of each stop, tail, and parking sign function of a single valve with a simple configuration, and to An object of the present invention is to provide a single valve control device capable of reducing battery consumption by switching a certain illumination level during lighting to a lower level.

In order to achieve such an objective, the present invention
A single bulb that uses reflected light from a single filament to have light distribution characteristics according to the three sign functions of stop, tail, and parking, and a control circuit that controls the illuminance of this single bulb.
and a detection means for detecting a stop of the vehicle, and the control circuit includes a pulse oscillator that oscillates pulses of a constant period based on the operation of the three switches that respectively activate the stop, tail and parking sign functions. , duty ratio variable means for varying the duty ratio by varying the pulse width oscillated by the pulse oscillator in accordance with the operation of each switch that activates each of the stop, tail, and parking sign functions, the pulse oscillator By controlling the energization of the single valve based on the output of the single valve, the illuminance level is varied in conjunction with each switch corresponding to each of the stop, tail, and parking sign functions, and the illuminance level is varied based on the detection result of the detection means. The illuminance level that is present while the single bulb is lit is switched to a lower level. Embodiments of the present invention will be described below with reference to the drawings.

〔Example〕

1 and 2 are a schematic configuration diagram and a circuit diagram of a single valve control device according to an embodiment of the present invention. In FIG. 1, 1 is an in-vehicle battery, 2 is an ignition switch (hereinafter referred to as an IG switch) whose one end is connected to the battery 1,
3 is a stop switch (hereinafter referred to as ST switch) connected in series with this IG switch 2;
5 is a tail switch (hereinafter referred to as a TA switch), and 5 is a parking switch (hereinafter referred to as a PA switch), and one ends of these switches 4 and 5 are connected to the battery 1 in parallel. 6
6 is a seating sensor consisting of a micro switch, a pressure switch, etc. installed in the driver's seat of the car, and this sensor 6 has a movable contact 6a when the driver is seated.
It is a sensor that closes to the TA contact 6b, and when the vehicle is stopped and the driver leaves, the movable contact 6a closes to the PA contact 6c. 10 is each of the above-mentioned switches 3 to 5
A control circuit 11 is a transistor for driving the normally known single valve 12 according to the stop, tail, and parking sign functions based on the on/off operation of the control circuit 10. Shown in Figure 2.

Here, 21 is a diode whose anode is connected to the other end of the ST switch 3, 22 is a diode whose anode is connected to the TA contact 6b of the seating sensor 6, which is connected to the other end of the TA switch 4 and the movable contact 6a. 23 is a diode whose anode is commonly connected to the other end of the PA switch 5 and the TA contact 6c of the seating sensor 6; the cathodes of these backflow prevention diodes 21 to 23 are commonly connected to the power supply line 24; A predetermined drive voltage Vcc is supplied to this power supply line 24 from the battery 1 when each of the switches 3 to 5 is turned on. 25 is a pulse oscillator composed of an operational amplifier 26, input resistors 27 and 28, a feedback resistor 29, and a time constant circuit 32 including a resistor 30 and a capacitor 31.
The drive voltage of the power supply line 24 is input to the input resistors 27 and 28.
The divided voltage is input to one input terminal of the operational amplifier 26, and a pulse with a constant period determined by the time constant of the resistor 30 and capacitor 31 of the time constant circuit 32 is oscillated, and the pulse width is described later. The duty ratio can be changed by a variable duty ratio circuit.

Further, 35 is a comparator having two input terminals, one of which is connected to a connection point c between the resistor 30 and the capacitor 31 of the time constant circuit 32 via a resistor 36. and,
A switch circuit 39 consisting of a bias circuit 38 including a transistor 37, a diode, and a resistor is configured for the capacitor 31, and this switch circuit 39 is turned on and off in response to the operation of the ST switch 3. In addition, the drive voltage of the power supply line 24 is connected to the other input terminal of a transistor 4 which is turned on and off by the output of the operational amplifier 26.
inputted via a switch circuit 41 consisting of 0,
Its input terminal is grounded through a resistor 42. A parallel circuit 46 is connected between one end of this resistor 42 and the output terminal a of the operational amplifier 26, which is a series body including a resistor 43, a resistor 44, and a switching transistor 45. A switch circuit 49 consisting of a bias circuit 48 including a transistor 47, a diode, and a resistor is configured for this transistor 45, and this switch circuit 49 turns on and off in response to the operation of the TA switch 4 to switch the transistor 45 Turn on and off. Further, the output terminal e of the comparator 35 is connected to the resistor 30 and the capacitor 31 via a diode 50 and a resistor 51, and the capacitor 3
By rapidly charging the pulse generator 1, the pulse width of the pulse oscillator 25 is changed to vary the pulse duty ratio. Note that each of the comparators 35 and the switch circuits 39, 41 and 4
9, a resistor 42, and a parallel circuit 46 constitute a variable duty ratio circuit. In Figure 2, 52
is a buffer transistor.

Next, the operation of the above embodiment will be explained with reference to the time chart of FIG. Here, the driver turns on the IG switch 2 and drives the car, and the seating sensor 6
It is assumed that the movable contact 6a is closed to the TA contact 6b. When the ST switch 3 is turned on while driving, the power supply voltage is changed from the battery 1 to the ST switch 3.
The switch 3 is connected to the operational amplifier 26 of the pulse oscillator 25 and the switch circuit 41 via the power line 24.
The signal is input to the switch circuit 39 as well as to the switch circuit 39. Then, the switch circuit 41 is turned on and at the same time, the switch circuit 39 is also turned on. As a result, the potential of the connection point b determined by the input resistors 27 and 28 and the feedback resistor 29 is inputted to the input terminal of the operational amplifier 26, and at the same time, the switch circuit 39 is turned on, and the potential of the input terminal of the operational amplifier 26 is inputted to the input terminal of the operational amplifier 26. The potential at the point is held at zero. As a result, regardless of the operation of the switch circuit 41, the output terminal point a of the operational amplifier 26 is at the voltage Vcc of the power supply line 24.
A potential approximately equal to that can be obtained steadily. As a result, the drive transistor 11 drives the single valve 12 with direct current (DC) via the buffer transistor 52. Therefore, the single bulb 12 lights up with high illuminance and functions as a stop lamp. Further, this indicator function can be activated with priority when the IG switch 2 is turned on, regardless of whether the TA switch 4 or the PA switch 5 is turned on.

In addition, when the IG switch 2 is turned off and the TA switch 4 is turned on, the power supply voltage is pulsed from the battery 1 through the TA switch 4, the movable contact 6b and TA contact 6b of the seating sensor 6, and the power line 24. The signal is input to the operational amplifier 26 of the oscillator 25 and the switch circuit 41, and is also input to the switch circuit 49. Then, this switch circuit 41 is turned on, and at the same time, the switch circuit 49 is also turned on, and the transistor 45 of the parallel circuit 46 is turned on.
Turn on. As a result, as shown in FIG. 3a, the potential Vb of the connection point b is input to the input terminal of the operational amplifier 26, and the potential Vc of the capacitor 31, which increases exponentially, is input to the input terminal of the operational amplifier 26. At this time, the potential Vc of the capacitor 31 is input to the input terminal of the comparator 35, and the potential of the connection point b is input to the input terminal thereof. On the other hand, when the input potential Vc exceeds
A high level output is generated at the output terminal e as shown in FIG. 3c. Therefore, this output is diode 5
0 is applied to the capacitor 31 through a resistor 51, which charges rapidly according to its time constant τ ₂ with the resistor 51. As a result, the output potential of the operational amplifier 26 instantaneously falls from a high level to a low level as shown in FIG. 3b, and at the same time, the capacitor 31 is connected to the resistor 30 as shown in FIG. The discharge occurs according to the time constant τ ₁ and this operation is repeated every cycle T of the output pulse. At this time, the potential of the connection point d input to the input terminal of the comparator 35 is set to Vd, and the resistor 42
Assuming that the resistance value of is R ₂ and the resistance values of the resistors 43 and 44 of the parallel circuit 46 are R ₃ and R ₄ respectively, this potential Vd is Vd=VccR ₂ /R ₂ +(R ₃ R ₄ ) (1) Therefore, the comparator 35 detects the potential of the connection point d.
The capacitor 31 is rapidly charged in response to Vd. Therefore, as shown in FIG. 3b, from the pulse oscillator 25, the pulse width that transitions from a low level to a high level and falls back to a low level, that is, the on-time t ₁ (t ₁ <T _ON ), is only shortened. A pulse with a constant off time t _pff is oscillated at , and the duty ratio of this pulse is set to D ₁ . Therefore, the above
When the TA switch 4 is on, the single bulb 12 is energized by the duty D ₁ of the pulse oscillated by the pulse oscillator 25, so it lights up at low illuminance and functions as a tail lamp. It can be activated with priority regardless of the ON operation of the switch 5.

On the other hand, when only the PA switch 5 is turned on, the power supply voltage from the battery 1 is input to the operational amplifier 26 of the pulse oscillator 25 via the PA switch 5 and the power line 24, and is also input to the switch circuit 41. Ru. Then, comparator 3
The same capacitor 31 as described above is connected to the input terminal of 5.
The potential Vc is input to the input terminal, but
Since the transistor 45 of the parallel circuit 45 is in an off state, the voltage at the connection point d divided by the resistors 42 and 43 is input. Therefore, if the potential of this connection point d is Vd ₁ , this potential Vd ₁ becomes Vd ₁ =VccR ₂ /R ₂ +R ₃ <VccR ₂ /R ₂ +(R ₃ R ₄ ) (2). As a result, the comparator 35 quickly charges the capacitor 31 using the potential Vd ₁ more quickly than when the voltage is Vd. Therefore, the pulse oscillator 25 oscillates a pulse whose on time t ₂ (t ₂ <t ₁ ) is even shorter and whose off time t _pff is constant,
Assuming that the duty ratio of this pulse is _D2 , this becomes even smaller than the above-mentioned duty ratio _D1 .
As a result, when the PA switch 5 is on, the single valve 12 has the duty ratio D ₂
By controlling the energization, the bulb 12 lights up at even lower illuminance and can function as a parking lamp.

Next, the driver stops the car and turns on the TA switch 4.
If you leave the driver's seat with
It switches to contact 6c. Therefore, the control circuit 10 controls the energization of the single bulb 12 in the same way as when the PA switch 5 is turned on, so that the illuminance level of the tail lamp that is currently lit can be switched to a lower parking level. At this time, as shown in FIG. 4, by inserting a seating sensor 7 between the base of the transistor 47 of the switch circuit 49 and the ground, which turns off when the driver sits down and turns on when the driver leaves, the TA When the driver leaves the switch 4 on, the seating sensor 7 is turned on and the transistor 47 is turned off, so that it can be operated in the same manner as the seating sensor 6 described above.

In this way, according to the above embodiment, three STs
A pulse oscillator 25 is provided which oscillates pulses of a constant period in conjunction with the operation of the switch 3, TA switch 4 and PA switch 5, and the width of the pulse oscillated from this pulse oscillator is changed according to the operation of each of the switches. In addition to varying the duty ratio, the priority of each switch is set to ST switch 3,
By applying the TA switch 4 and the PA switch in that order and controlling the single bulb based on the output of the pulse oscillator, this single bulb can function as a stop lamp, a tail lamp, and a parking lamp with an illuminance depending on the purpose of use. . Furthermore, by changing the pulse width oscillated by the pulse oscillator 25 and varying its duty ratio, it is possible to change the on-time of the drive pulse and keep the on-time constant.
When the duty ratio is small (10% or less), the duty ratio can be varied more easily than when the frequency is constant and only the duty ratio is changed. Moreover, the frequency does not become infinitely small, and flickering of the lighting due to on/off can be prevented. Furthermore, when the driver leaves the driver's seat with the TA switch 4 on, the illuminance level can be switched to a lower parking level, thereby reducing battery power consumption.

FIG. 5 is a circuit diagram equivalent to FIG. 2 showing another embodiment of the present invention. The difference from FIG. 2 is that in order to change the pulse width of the pulse oscillator 25, By varying the time constant of the time constant circuit 32 to be inserted according to the operation of the ST switch 3, TA switch 4, and PA switch, the resistor 3
The charging time constant of the capacitor 31 is controlled by changing the discharging time constant of the capacitor 31 and the capacitor 31. Then, the seating sensor 7 similar to that shown in FIG. 4 is connected to a parallel circuit 64.
This is because the transistor 63 is inserted between the base of the transistor 63 and the ground. In this case, a resistor 61 and a resistor 6 are connected across the resistor 30 of the first time constant circuit 32.
2. A parallel circuit 64 with a series body including the switching transistor 63 and a backflow prevention diode 65 connected in series to the parallel circuit 64 are connected in parallel, and a bias circuit 66 is formed from the diode of the transistor 63 and a resistor. is added so that when only the TA switch 4 is turned on, the transistor 63
is configured to turn off.

According to this embodiment, when the ST switch 3 is turned on, the switch circuit 39 is turned on, so that the pulse oscillator 25 generates a DC level output as in the above embodiment.

Furthermore, when only the TA switch 4 is turned on, the transistor 63 of the parallel circuit 64 is turned off and the resistor 61 is inserted in parallel with the resistor 30 of the time constant circuit 32, so the resistance value of the resistor 30 is
R ₁ , the resistance value of the resistor 61 is R ₅ , and the capacitance value of the capacitor 31 is C ₁ , the above discharge time constant τ _pff is τ _pff = C ₁ (R ₁ R ₅ ) < C ₁ R ₁ (3) becomes. Therefore, by controlling the charging time constant of the time constant circuit 32 to the capacitor 31, the pulse oscillator 25
On-time T _{1 of the pulse oscillated from T 1} (T ₁ < T _ON )
The duty ratio can be varied by changing .
Also, if only PA switch 5 is turned on,
Since the transistor 63 of the parallel circuit 64 is turned on and the parallel circuit 64 consisting of resistors 61 and 62 is inserted to the resistor 30 of the time constant circuit 32, the discharge time constant τ _pff is the resistance value of the resistor 62 R ₆ Then, τ _pff = C ₁ (R ₁ R ₅ R ₆ ) < C ₁ (R ₁ R ₅ ) (4). Therefore, the duty ratio can be varied by changing the on time T ₂ (T ₂ <T ₁ ) of the pulse oscillated from the pulse oscillator 25 in the same manner as when the TA switch 4 is operated. Therefore, this embodiment can also achieve the same effects as the above-mentioned embodiments.

FIG. 6 is a circuit diagram of the main part corresponding to FIG. 2 showing another embodiment of the present invention. The difference from FIG. 2 is that a detection sensor 8 that turns on and off in conjunction with the handbrake is inserted between the base of the switching transistor 70 and the ground via a resistor 71 as a means for detecting the stoppage of the vehicle. The base of the transistor 70 is connected to the IG switch 2 of FIG. 2 via a resistor 72 and a diode 73. The collector of the transistor 70 is connected to the midpoint between the resistors 74 and 75 connected between the base of the transistor 45 and the collector of the transistor 47. In this embodiment, when only the TA switch 4 is on, the handbrake is pulled to stop the car, and the IG switch 2 is on to turn off the engine, the detection sensor 8 is turned on (closed) and the vehicle is stopped. Transistor 70 is turned on. Therefore, the transistor 45 is turned off, and the illuminance level of the lit tail lamp can be switched to the parking level in the same way as described above.

FIG. 7 shows a fifth embodiment of the present invention.
It is a circuit diagram of the main parts corresponding to the figure, and includes a detection sensor 8, a transistor 70, and a diode 7 similar to those in FIG.
3 and resistors 71, 72, 74, and 75 as transistor 63 and bias circuit 6 in FIG.
6, the same effect as the embodiment shown in FIG. 6 described above can be obtained.

FIG. 8 is a second embodiment showing still another embodiment of the present invention.
It is a circuit diagram of the main part corresponding to the figure. The difference from FIG. 6 is that the means for detecting the stoppage of the vehicle consists of a speed sensor 80, a sensor circuit 81, and a retriggerable one-shot multi-circuit 82 that is triggered by an output pulse from the sensor circuit. 82 is input to the transistor 70. In addition, in FIG. 8, 83 is a speedometer control section. According to this embodiment, when only the TA switch is on, the vehicle is stopped, and the engine is off, the retriggerable one-shot multi-circuit 82 sends a low level output to the transistor 70 in accordance with the traveling speed OKm/Hr. The retriggerable one-shot multi-circuit 82 inputs the illuminance level of the illuminated tail lamp to turn it on.
It is possible to switch to the parking level after a certain period of time determined by . Note that a tachometer or the like that detects the number of revolutions of the engine may be used as a means for detecting whether the engine is turned off.

FIG. 9 is a fifth embodiment showing still another embodiment of the present invention.
This is a circuit diagram of the main parts corresponding to the one shown in FIG. By controlling the on/off state of transistors 70 and 76 based on the above-mentioned results, the same effect as that of the embodiment shown in FIG. 8 described above can be obtained.

FIG. 10 is a schematic configuration diagram showing still another embodiment of the present invention, and the functions of the embodiment of FIG. 8 and the IG
When switch 2 is on and the car is stopped and ST switch 3 is kept on, a microprocessor (CPU
90). Here, the CPU
Reference numeral 90 uses a CPU that can display various information such as a speedometer, trip meter, and odometer on a meter display section 92. An input signal associated with this is input through the interface 91, and a distance pulse from a distance sensor 89 that detects the distance traveled by the car is directly input. In normal times, the ST
The single bulb 12 (also referred to as a lamp) is energized in accordance with the priority order of the switch 3, TA switch 4, and PA switch 5. At this time, among the indicator functions of the single bulb 12, the on-duty of the stop lamp is 100% (“1”), and the on-duty of the tail lamp and parking lamp is A% (“A”) and B% (“B”), respectively. is 1
It is assumed that there is a relationship of >A>B.

When the IG switch 2 is on, the CPU 90 receives a distance pulse from the distance sensor 89.
When the ON signal of ST switch 3 is input, this
The CPU 90 proceeds to steps 110-112 as shown in the flowchart of FIG. At this time, if there is a distance pulse from the distance sensor 89 in step 112, the process proceeds to step 113 and resets the set time Ts of the timer. Then, in step 114, the drive output of duty 1 is changed to single valve 1.
2, and the stop lamp is lit by the duty 1. Further, if it is determined in step 112 that there is no distance pulse, the process advances to step 115. Here, if the ON state of the ST switch 3 continues for a certain period of time and that time Ts exceeds the set time Ts of the timer, the process advances to step 116, and the step 1 described above is performed.
14 is switched to the tail level of duty A, and this operation is continued as long as the car is stopped and the ST switch 3 remains on. and,
When the ST switch 3 is turned off, the CPU 90 proceeds to steps 118 and 116 and steps 119 and 120.
The operation depends only on whether the TA switch 4 is turned on or the PA switch 5 is turned on, and the operation returns to normal.

On the other hand, when the IG switch 2 is turned off in step 110 and the TA switch 4 is turned on in step 121, the process advances to step 122. At this time, TA
When switch 4 remains on (Tt) for a certain period of time and exceeds the timer set time T _T , the duty A tail level (step 126) is switched to the duty B barking level (step 125) and this operation is continued. It turns out. In addition, CPU90
is activated when IG switch 2 is on, and the meter is displayed.
Control the lamp. Furthermore, when the IG switch 2 is off and the TA switch 4 is on, the CPU 90 operates to control the lamps, but the meter display operates to turn off all lights.

〔Effect of the invention〕

As explained above, according to the single valve control device of the present invention, a pulse oscillator is provided that oscillates pulses with a constant period in conjunction with the three switches, ST switch, TA switch, and PA switch, and the pulse oscillator generates oscillations. The duty ratio is varied by changing the pulse width of each switch according to the operation of each switch, and the single bulb is controlled based on the duty ratio, so that the single bulb can be used as a stop lamp or a stop lamp at an illuminance depending on the purpose of use. Can function as a tail light and parking light. In addition, by changing the pulse width of the pulse oscillator, the on time can be varied and the off time can be made constant.
The duty ratio can be easily changed, and flickering during lighting can be prevented. Furthermore, when the car is stopped, the illuminance level that is present when the single bulb is turned on can be switched to a lower level, so it has excellent effects as an automotive lamp, such as reducing battery consumption.

[Brief explanation of drawings]

1 and 2 are a schematic configuration diagram and a circuit diagram of a single valve control device according to an embodiment of the present invention, FIG. 3 is a waveform diagram of the main parts used for the operation of the above embodiment, and FIG. 4 is a diagram of the above-mentioned A circuit diagram showing a modification of the embodiment, FIG. 5 is a circuit diagram showing another embodiment of the present invention,
6 to 9 are circuit diagrams of main parts showing another embodiment of the present invention, FIG. 10 is a schematic configuration diagram showing still another embodiment of the present invention, and FIG. 11 is an implementation of FIG. 10. This is a flowchart for example operation. 1... Battery, 2... Ignition switch (IG switch), 3... Stop switch (ST switch), 4... Tail switch (TA switch), 5... Parking switch (PA switch), 6, 7... ... Seating sensor, 8... Detection sensor,
10...Control circuit, 11...Drive transistor, 12...Single valve, 21-23...
Diode, 25... Pulse oscillator, 26... Operational amplifier, 27, 28... Resistor, 29... Feedback resistor, 32... Time constant circuit, 35... Comparator, 39, 41, 49... Switch circuit, 42 ~
44, 61-62... Resistor, 45, 63... Switching transistor, 46, 64... Parallel circuit, 65... Diode, 80... Speed sensor, 89... Distance sensor.

Claims (1)

[Claims] 1. A single bulb that utilizes the reflected light from one filament and has light distribution characteristics that correspond to the three sign functions of stop, tail, and parking;
It is equipped with a control circuit that controls the illuminance of this single bulb and a detection means that detects when the vehicle is stopped, and the control circuit controls the operation of the three switches that respectively operate the stop, tail, and parking sign functions. a pulse oscillator that oscillates a pulse with a constant period based on the pulse oscillator, and a duty ratio that is varied by changing the width of the pulse oscillated from the pulse oscillator in accordance with the operation of each switch that operates the stop, tail, and parking sign functions. and a duty ratio variable means, and by controlling the energization of the single valve based on the output of the pulse oscillator, the illuminance level is adjusted in conjunction with each switch corresponding to each of the stop, tail, and parking sign functions. 1. A single valve control device, characterized in that the illuminance level that is present during lighting of the single bulb is switched to a lower level based on the detection result of the detection means.