JPH09277872A - Rheostat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rheostat which can regulate the brightness of a lighting automatically in conformity with a circumferential conduction without increasing the number of part items. SOLUTION: The rheostat is provided with a transistor 16 for lighting a lamp 15 for dimming by the supply of a current from a battery VB and a control circuit 14 for inputting an operation signal based on the operation of a light control switch 2 for lighting a tail lamp 3, a low beam head lamp 5 and a high beam head lamp 6 and a switch 4 for switching the low beam head lamp 5 or the high beam head lamp 6 and judging a circumferncial condition based on the operation signal and also controlling the transistor 16 to regulate the brightness of the lamp 15 for dimming based on the judgment.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rheostat.

[0002]

2. Description of the Related Art Conventionally, illumination is provided in instruments such as a supermeter and switches such as an air conditioner switch of an automobile, but the instruments and the switches may be difficult to see due to the ambient brightness. Therefore, a vehicle light control device (rheostat) is provided. A dimming knob is attached to the rheostat, and a driver or the like operates the dimming knob to adjust the brightness of the illumination so that the instruments and switches can be easily seen.

[0003]

However, it is troublesome for the driver or the like to operate the dimming knob to adjust the brightness of the illumination each time the ambient conditions change. or,
It was very troublesome for the driver to operate the light control knob while the driver was driving.

The present invention has been made to solve the above problems, and an object thereof is to automatically adjust the brightness of illumination without increasing the number of parts and according to the ambient conditions. To provide a rheostat that can.

[0005]

In order to solve the above problems, the invention according to claim 1 provides a driving circuit for supplying a current from a battery to turn on a dimming lamp, a tail lamp, a low beam headlamp, and Input an operation signal based on the operation of the first switch for turning on the high beam headlamp and the second switch for switching the low beam headlamp or the high beam headlamp, and determine the ambient condition based on the operation signal. And a control circuit that controls the drive circuit to adjust the brightness of the dimming lamp based on the determination of the determination circuit.

According to a second aspect of the present invention, in the rheostat according to the first aspect, the determination circuit includes the first and second determination circuits.
Second switch and third for lighting fog lights
An operation signal based on the operation with the switch is input, and the ambient condition is determined based on the operation signal.

[0007] The invention described in claim 3 is the first or second invention.
In the rheostat described in (1), the drive circuit is a switching element and is on / off controlled based on a control signal from the control circuit to control the amount of current supplied to the dimming lamp.

Therefore, according to the invention of claim 1,
The drive circuit supplies current from the battery to turn on the dimming lamp. The determination circuit inputs an operation signal based on the operation of the first switch for turning on the tail lamp, the low beam headlamp and the high beam headlamp, and the second switch for switching the low beam headlamp or the high beam headlamp, Ambient conditions are determined based on the operation signal. The control circuit controls the drive circuit to adjust the brightness of the dimming lamp based on the determination of the determination circuit.

According to the second aspect of the invention, the determination circuit inputs an operation signal based on the operation of the first and second switches and the third switch for turning on the fog lamp, and outputs the operation signal. The ambient condition is determined based on the operation signal.

According to the third aspect of the invention, the switching element is on / off controlled based on a control signal from the control circuit to control the amount of current supplied to the dimming lamp.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows an electrical configuration of a vehicle lighting device 1. The light control switch 2 as the first switch of the lighting device 1 is a general light control switch, and is provided in the driver's seat of an automobile. The light control switch 2 includes a movable terminal 2a connected to a general ignition switch (IG) and three terminals OFF, TL and HD. The terminals OFF, TL, and HD are arranged in this order, and the movable terminal 2a is shaped so that adjacent terminals can be simultaneously connected.

The terminal TL is grounded via the tail lamp 3. The terminal HD is connected to the movable terminal 4a of the changeover switch 4 as the second switch, and the movable terminal 4a is grounded via the low beam headlamp 5 and the terminal Lo via the high beam headlamp 6. Switch between Hi and Hi. Further, one end of the fog switch 7 as the third switch is connected to the ignition switch, and the other end is grounded via the fog lamp 8.

On the other hand, the terminals TL, Lo, Hi and the fog switch 7 are connected in parallel to the input terminals IN1 to IN4 of the control circuit 14 serving as the determination circuit and control circuit of the rheostat 9 through the resistors 10 to 13, respectively. It is connected.

Therefore, when the movable terminal 2a is connected to the terminals OFF and TL, the tail lamp 3 is turned on by the power supply from the ignition switch, and the H level signal is input to the input terminal IN1 of the control circuit 14. When the movable terminal 4a of the changeover switch 4 is connected to the terminal Lo while the movable terminal 2a is connected to the terminals TL and HD, the tail lamp 3 and the low beam headlamp 5 are turned on, and the input terminals IN1 and IN2 are set to H level. The level signal is input. Here, when the movable terminal 4a is connected to the terminal Hi, the tail lamp 3 and the high beam headlamp 6 are turned on,
An H level signal is input to each of the input terminals IN1 and IN3. On the other hand, the fog lamp 8 is turned on when the fog switch 7 is turned on, and an H level signal is input to the input terminal IN4.

The control circuit 14 controls the input terminals IN2 and IN3 of the control circuit 14 based on the operation of the changeover switch 4.
Only when the H-level signal input to is continuously input for a predetermined time (about 5 seconds), the H-level signal is determined as a valid signal. This is to distinguish from the instantaneous H-level signal input to the input terminals IN2 and IN3 due to passing or the like, and prevent the control circuit 14 from malfunctioning.

On the other hand, one end of a dimming lamp 15 incorporated in instruments such as a supermeter or switches such as an air conditioner switch is connected to the positive electrode of the battery VB, and the other end is connected to the emitter grounded drive circuit of the rheostat 9. And a collector of the NPN transistor 16 as a switching element. The base of the transistor 16 is connected to the output terminal OUT1 of the control circuit 14 via the resistor 17.
And is adapted to receive a pulse from its output terminal OUT1. The dimming lamp 15 lights up brighter as the transistor 16 is on longer. That is, the duty ratio of the pulse is changed by the control circuit 14 and the pulse is output to the base of the transistor 16 to control the current supplied to the dimming lamp 15 to control the dimming lamp 15. It is designed to adjust the brightness.

The control circuit 14 includes a light control switch 2, a changeover switch 4 and a fog switch 7.
The ambient condition is determined by the combination of H-level signals input to the input terminals IN1 to IN4 based on the respective operations. Then, the control circuit 14 changes the duty ratio of the pulse output to the base of the transistor 16 in accordance with the ambient conditions, and switches the dimming lamp 15 to a brightness suitable for the ambient conditions. Here, the duty ratio is the ratio of the time that is at the H level in one cycle of the pulse, and the greater the duty ratio, the more
The transistor 16 is on for a long time. That is,
The dimming lamp 15 lights up brightly. Duty ratios D1 to D5, which will be described later, are set in steps from large to small in this order of description.

In the present embodiment, the following first to fifth items will be given.
It is divided into light control stages A to E. In the first to fifth dimming stages A to E, the output terminal OUT1 of the control circuit 14 outputs pulses having duty ratios D1 to D5 corresponding to the dimming stages A to E, respectively. That is, the first to fifth dimming steps A
In the order from E to E, the brightness of the dimming lamp 15 is set in five steps from light to dark. The data of the duty ratios D1 to D5 corresponding to the first to fifth dimming stages A to E are
EEPROM (Electrically) provided in the control circuit 14
It is stored as initial value data in the Erasable and Programmable ROM) 14a and is preset.

First dimming step A; both the light control switch 2 and the fog switch 7 are off,
When all of the tail lamp 3, the low beam headlamp 5, the high beam headlamp 6, and the fog lamp 8 are in a non-lighting state, that is, when the input terminals IN1 to IN4 are all at the L level, the control circuit 14 determines that the ambient condition is daytime. To determine. Then, the control circuit 14 sets the duty ratio D1 preset based on the initial value data so that the brightness of the dimming lamp 15 matches the daytime brightness, that is, the dimming lamp 15 becomes the brightest. Pulse is output to the base of the transistor 16.

Second dimming step B: The light control switch 2 is operated to connect the movable terminal 2a to the terminal TL,
When the fog switch 7 is on and both the tail lamp 3 and the fog lamp 8 are lit,
That is, when the H-level signal is input only to the input terminals IN1 and IN4, the control circuit 14 determines that the ambient condition is the fog (daytime) state. The control circuit 14 determines that the brightness of the dimming lamp 15 matches the brightness of fog (daytime) based on the initial value data, that is, the dimming lamp 15 is darker than the first dimming stage A. Therefore, a pulse having a preset duty ratio D2 is output to the base of the transistor 16.

Third dimming step C: The light control switch 2 is operated to connect the movable terminal 2a to the terminal TL,
Further, when the fog switch 7 is off and only the tail lamp 3 is lit, that is, the input terminal IN
When the H level signal is input only to 1, the control circuit 14 determines that the ambient condition is early morning, evening, or rain. Then, the control circuit 14 causes the brightness of the dimming lamp 15 to match the brightness of early morning, evening, or rain on the basis of the initial value data, that is, the dimming lamp 15 is in the second dimming stage B. A pulse having a preset duty ratio D3 is output to the base of the transistor 16 so that the brightness becomes darker.

Fourth light control stage D: The light control switch 2 is operated to connect the movable terminal 2a to the terminals TL and HD, and the movable terminal 4a of the changeover switch 4 is connected to the terminal Lo. When both the low-beam headlamps 5 are turned on, that is, the input terminal I
When the H-level signal is input only to N1 and IN2, the control circuit 14 determines that the ambient condition is at night or in the tunnel based on the initial value data. Then, the control circuit 14 causes the brightness of the dimming lamp 15 to match the brightness at night or in the tunnel, that is, the brightness of the dimming lamp 15 becomes darker than the third dimming stage C. Then, a pulse having a preset duty ratio D4 is output to the base of the transistor 16.

Fifth light control stage E: The light control switch 2 is operated to connect the movable terminal 2a to the terminals TL and HD, and the movable terminal 4a of the changeover switch 4 is connected to the terminal Hi. When both the high beam headlamps 6 are turned on, that is, the input terminal I
When the H-level signal is input only to N1 and IN3, the control circuit 14 determines that the ambient condition is night (ambient darkness) based on the initial value data. Then, the control circuit 14
Is a pulse of a preset duty ratio D5 so that the brightness of the dimming lamp 15 matches the brightness at night (peripheral darkness), that is, the dimming lamp 15 is darkest. Output to.

The control circuit 14 has panel input terminals IN5 to IN11 and panel output terminals OUT2 and OUT.
3 are provided. Panel input terminals IN5, IN6
Are resistors 18, 19 and illuminance increasing switch 20, respectively.
a, the illumination lowering switch 20b, and is connected in parallel to the ignition switch. Also, the panel input terminal I
N7 to IN11 are connected in parallel to the ignition switch via resistors 21 to 25 and dimming stage switches 26a to 26e, respectively. On the other hand, the panel output terminal OU
T2 and OUT3 are resistors 27 and 28 and a display unit 2, respectively.
It is connected in parallel to the ignition switch via 9a and 29b.

The above-mentioned switches 20a, 20b, 26
The a to 26e and the display portions 29a and 29b are arranged on the panel 9a of the rheostat 9, as shown in FIG.
The panel 9a is provided at a position where the driver in the driver's seat can easily operate it.

Here, the dimming lamp 15 has the first to fifth dimming stages A to E set in advance as described above, but it may be difficult to see due to individual differences of the driver or the like.
Therefore, the illuminance increasing switch 20a is adapted to brighten the dimming lamp 15 when the switch 20a is turned on, and to maintain the brightness thereof when set to off.
Further, the illuminance lowering switch 20b is adapted to darken the dimming lamp 15 when the switch 20b is turned on, and to keep its brightness set when turned off. That is, the brightness of the dimming lamp 15 is adjusted by operating the illuminance increase / illuminance decrease switches 20a and 20b.

Illumination raising and lowering switch 20
By adjusting the brightness of the dimming lamp 15 by operating a and 20b, and then turning on the dimming stage switches 26a to 26e, the adjusted brightness of the dimming lamp 15, that is, the duty ratio. Is stored in the EEPROM 14a of the control circuit 14. or,
The EEPROM 14a stores the adjusted brightness of the dimming lamp 15 even if the power supply to the dimming lamp 15 is cut off and the power is supplied again. In other words, even if the power supply is cut off, the dimming lamp 15 is turned off and then turned on again based on the power supply, the data of the duty ratio stored in the EEPROM 14a is not erased and is turned on with the adjusted brightness. It is like this. The dimming step switches 26a to 26e correspond to the above-described first to fifth dimming steps A to E, respectively, in this order of description.

Further, in the present embodiment, a liquid crystal panel is used for each of the display portions 29a and 29b. Display 29
A is displayed based on the selected first to fifth dimming steps A to E. On the other hand, the display unit 29b makes a display based on the degree of brightness of the dimming lamp 15.

Next, the operation of the rheostat 9 constructed as above will be described. First, both the light control switch 2 and the fog switch 7 are turned off.
This is tail lamp 3, low beam headlamp 5,
All of the high beam headlamp 6 and the fog lamp 8 are in a non-lighting state. At this time, the control circuit 14 determines that the ambient condition is daytime. Then, in order to set the brightness of the dimming lamp 15 to the first dimming stage A, a pulse having a duty ratio D1 matching the setting is output to the base of the transistor 16. Then, the dimming lamp 15 is set to the brightness of the first dimming stage A. At this time, the panel 9a
The display unit 29a displays the first dimming stage A, and the display unit 29b displays the degree of brightness of the dimming lamp 15.

When the driver or the like turns on the illuminance increasing switch 20a, the dimming lamp 15 becomes bright, and when turned off, the data of the duty ratio of the brightness is held.
When the illuminance lowering switch 20b is turned on, the dimming lamp 15 becomes dark, and when it is turned off, the data of the duty ratio of the brightness is held. That is, the driver or the like adjusts the brightness of the dimming lamp 15 by operating the illuminance increase / decrease switches 20a and 20b. At this time, when the driver or the like turns on the dimming stage switch 26a,
The adjusted duty ratio data of the brightness of the dimming lamp 15 is stored in the EEPROM 14a.

Next, the light control switch 2 is operated to connect the movable terminal 2a to the terminal TL, and the fog switch 7 is turned on. Then, both the tail lamp 3 and the fog lamp 8 are turned on. At this time, the control circuit 1
In No. 4, the ambient condition is determined to be the fog (daytime) state. Then
In order to set the brightness of the dimming lamp 15 to the second dimming stage B, a pulse having a duty ratio D2 matching the setting is output to the base of the transistor 16. Then, the dimming lamp 15 is set to the brightness of the second dimming stage B. At this time, the display of the second dimming stage B is displayed on the display unit 29a of the panel 9a, and the display unit 29b displays
The degree of brightness of the dimming lamp 15 is displayed.

As described above, the driver or the like adjusts the brightness of the dimming lamp 15 by operating the illuminance raising / lowering switches 20a, 20b. At this time, when the driver or the like turns on the dimming stage switch 26b,
The adjusted duty ratio data of the brightness of the dimming lamp 15 is stored in the EEPROM 14a.

Next, the light control switch 2 is operated to connect the movable terminal 2a to the terminal TL. Then, only the tail lamp 3 is turned on. At this time, the control circuit 14
Determines that the ambient conditions are early morning, evening, or rain. Then, in order to set the brightness of the dimming lamp 15 to the third dimming stage C, a pulse having a duty ratio D3 matching the setting is output to the base of the transistor 16. Then, the dimming lamp 15 is set to the brightness of the third dimming stage C. At this time, on the display unit 29a of the panel 9a,
The display as the third dimming stage C is performed, and the display unit 29b
Indicates the degree of brightness of the dimming lamp 15.

As described above, the driver or the like adjusts the brightness of the dimming lamp 15 by operating the illuminance raising / lowering switches 20a, 20b. At this time, when the driver or the like turns on the dimming stage switch 26c,
The adjusted duty ratio data of the brightness of the dimming lamp 15 is stored in the EEPROM 14a.

Next, the light control switch 2 is operated to connect the movable terminal 2a to the terminals TL and HD, and
The movable terminal 4a of the changeover switch 4 is connected to the terminal Lo. Then, both the tail lamp 3 and the low-beam headlamp 5 are turned on. At this time, the control circuit 14 determines that the ambient condition is at night or in a tunnel. Then
In order to set the brightness of the dimming lamp 15 to the fourth dimming stage D, a pulse having a duty ratio D4 matching the setting is output to the base of the transistor 16. Then, the dimming lamp 15 is set to the brightness of the fourth dimming stage D. At this time, the display unit 29a of the panel 9a displays as the fourth light control stage D, and the display unit 29b displays
The degree of brightness of the dimming lamp 15 is displayed.

As described above, the driver or the like adjusts the brightness of the dimming lamp 15 by operating the illuminance raising / lowering switches 20a, 20b. At this time, when the driver or the like turns on the dimming stage switch 26d,
The adjusted duty ratio data of the brightness of the dimming lamp 15 is stored in the EEPROM 14a.

Next, the light control switch 2 is operated to connect the movable terminal 2a to the terminals TL and HD, and
The movable terminal 4a of the changeover switch 4 is connected to the terminal Hi. Then, both the tail lamp 3 and the high beam headlamp 6 are turned on. At this time, the control circuit 14 determines that the ambient condition is night (peripheral darkness). Then, in order to set the brightness of the dimming lamp 15 to the fifth dimming stage E, a pulse having a duty ratio D5 matching the setting is output to the base of the transistor 16. Then, the dimming lamp 15 is set to the brightness of the fifth dimming step E. At this time, the display of the fifth dimming stage E is displayed on the display unit 29a of the panel 9a, and the degree of brightness of the dimming lamp 15 is displayed on the display unit 29b.

As described above, the driver or the like adjusts the brightness of the dimming lamp 15 by operating the illuminance increasing and illuminance decreasing switches 20a and 20b. At this time, when the driver or the like turns on the dimming stage switch 26e,
The adjusted duty ratio data of the brightness of the dimming lamp 15 is stored in the EEPROM 14a.

As described above, according to this embodiment,
It has the following features. (1) The control circuit 14 determines the ambient condition based on the operations of the light control switch 2, the changeover switch 4, and the fog switch 7, and automatically adjusts the brightness of the dimming lamp 15 that matches the ambient condition. can do.

(2) The driver or the like can adjust the brightness of the dimming lamp 15 as desired by operating the illuminance increasing and illuminance decreasing switches 20a and 20b, and then the dimming step switches 26a to 26a. By turning on 26e,
The adjusted brightness of the dimming lamp 15 can be stored in the EEPROM 14a of the control circuit 14.

(3) Since the judgment of the ambient conditions is made based on the operation of each of the light control switch 2, the changeover switch 4 and the fog switch 7, no extra parts such as a sensor are required and the sensor is used. The brightness of the dimming lamp 15 can be adjusted more reliably than in the case of doing so.

(4) The display unit 29a makes a display based on the selected first to fifth dimming steps A to E, and the display unit 29b makes a display based on the degree of brightness of the dimming lamp 15. Since the display is made, the driver or the like can easily know the dimming stages A to E and the degree of brightness of the dimming lamp 15.

The present invention may be modified as follows, and the same operation and effect can be obtained in such a case. (1) In the above embodiment, the circuit configuration using the NPN transistor 16 is used, but a circuit configuration using another switching element may be used. For example, PNP transistor, MOS transistor, IGBT (Insulate)
d Gate Bipolar Transiste
r) or the like may be used.

(2) In the above embodiment, the control circuit 14
Determines the ambient condition based on the operation of each of the light control switch 2, the changeover switch 4 and the fog switch 7, and adjusts the light control lamp 1 that meets the ambient condition.
Although the brightness of 5 was set in 5 steps, the light control switch 2, the changeover switch 4 and the fog switch 7 were set.
The ambient condition may be determined based on at least one operation in the above.

(3) In the above embodiment, the panel 9a is provided with the illuminance raising and lowering switches 20a and 20b, the dimming step switches 26a to 26e, and the display portions 29a and 29b, respectively, but it is not necessary to provide them. .

(4) In the above embodiment, the brightness of the dimming lamp 15 that has been dimmed is stored in the EEPROM 14a, but the present invention is not limited to this. For example, it may be an EPROM, a RAM backed up by a battery VB, or the like.

(5) In the above embodiment, the panel 9a of the rheostat 9 has an illuminance increase / illumination decrease switch 20.
a, 20b, dimming step switches 26a to 26e, and display units 29a, 29b are provided.
A reset switch or the like may be provided to adjust 5 to a preset brightness.

Although the respective embodiments of the present invention have been described above, technical ideas other than the claims which can be understood from the respective embodiments will be described below together with their effects. (A) In the rheostat according to any one of claims 1 to 3, an adjusting unit (in the specification, an illuminance increase / illumination decrease switch) 20a for adjusting the brightness of the dimming lamp 15 is provided.
20b and storage means for storing data corresponding to the brightness of the dimming lamp 15 adjusted based on the adjustment of the adjusting means 20a, 20b (EEPR in the specification.
OM) 14a. Therefore, the driver can adjust the brightness of the dimming lamp 15 according to his / her preference and store the data corresponding to the adjusted brightness of the dimming lamp 15.

(B) The rheostat described in (a) above is provided with display portions 29a and 29b for displaying the degree of brightness of the dimming lamp 15. Therefore, the driver or the like can easily know the degree of brightness of the dimming lamp 15.

[0050]

As described above in detail, according to the present invention, it is possible to provide a rheostat capable of automatically adjusting the brightness of illumination without increasing the number of parts and according to the ambient conditions. .

[Brief description of drawings]

FIG. 1 is an electrical configuration diagram of a vehicle lighting device according to an embodiment.

FIG. 2 is a block diagram of a rheostat panel.

[Explanation of symbols]

2 ... Light control switch as first switch, 3 ... Tail lamp, 4 ... Changeover switch as second switch, 5 ... Low beam headlamp, 6 ... High beam headlamp, 7 ... Fog switch as third switch, 8 ... Fog lamp, 14 ... Control circuit as judgment circuit and control circuit, 15 ... Dimming lamp, 16
... NPN transistor as drive circuit and switching element, VB ... Battery.

Claims (3)

[Claims] 1. A drive circuit (16) for supplying current from a battery (VB) to turn on a dimming lamp (15), a tail lamp (3), a low beam headlamp (5) and a high beam headlamp (6). First switch (2) for lighting the vehicle, and low beam headlamp (5)
Alternatively, a determination circuit (14) for inputting an operation signal based on an operation with a second switch (4) for switching the high beam headlamp (6) and determining an ambient condition based on the operation signal; Based on the judgment of (14), the drive circuit (1) is arranged to adjust the brightness of the dimming lamp (15).
And a control circuit (14) for controlling 6). 2. The rheostat according to claim 1, wherein the determination circuit (14) includes a third switch (1) for turning on the first and second switches (2, 4) and a fog lamp (8). A rheostat that receives an operation signal based on the operation of 7) and determines the ambient condition based on the operation signal. 3. The rheostat according to claim 1, wherein the drive circuit (16) is a switching element (16) and is on / off controlled based on a control signal from the control circuit (14). A rheostat adapted to control the amount of current supplied to the dimming lamp (15).