JP2005061920A - Self-luminous pointer drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-luminous pointer drive for performing electrical connection at a body (meter) side and a pointer side with two poles, simplifying the configuration, and controlling a light source for lighting in the pointer individually. <P>SOLUTION: A pointer section and a meter section are electrically connected by the two points of a power line 32 and a GND line 32, and a control signal for controlling the on/off of a light source 23 for lighting a plurality of LEDs, or the like is transmitted by a light signal between a light-emitting element 21a of the meter section and a light receiving element 21b of the pointer section. With a rotary axis as a center, a reflection member 33 for cylindrically surrounding the outside of the light emitting element 21a may be provided. The light signal emitted from the light emitting element 21a is reflected by the reflection member 33, and enters the light receiving element 21b that travels by the rotation of the pointer section. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a self-luminous pointer driving device in which a pointer provided with a light emitting element is attached to a meter body, and electrical connection to the pointer side is two-pole.

  In general, a vehicle is equipped with a meter that allows a driver to recognize a measured value such as a vehicle speed by moving a pointer on a dial. Since the driver needs to recognize the measured value from the meter even at night, the meter needs to be lit. In that case, a method of causing the pointer itself to emit light has been proposed for its good visibility.

In this method, it is necessary to supply power to the pointer side in order to light a light emitting element such as an LED in the pointer. Patent Document 1 discloses a method of supplying power to a pointer by providing a spiral FPC (flexible printed wiring) around a drive shaft of a motor that drives the pointer.
Japanese Patent Laid-Open No. 10-300529 (2nd page, FIG. 2)

  Conventionally, when a plurality of light emitting elements are provided in a pointer and controlled individually, three or more lines of electrical contact must be formed between the main body side and the pointer side. If power supply to the self-luminous pointer as described above is performed by two-pole electrical contact, it is impossible to change the luminance balance and to independently control each light emitting element. However, forming three or more electrical contacts is difficult to reduce in size and complicated in structure, and thus difficult to put into practical use.

  The present invention has been made in view of the above problems, and the electrical connection between the main body (meter) side and the pointer side is performed with two poles, and the light emitting elements in the pointer are individually controlled while the configuration is simplified. It is an object of the present invention to provide a self-luminous pointer driving device that can be used.

  In order to achieve such an object, as shown in FIG. 1, the invention according to claim 1 includes a plurality of illumination light sources 23, a pointer portion that emits light when at least one of the illumination light sources 23 is turned on, and the pointer Self-luminous having a meter part that rotatably supports the part by a rotating shaft, and a power line 32 and a GND line 32 that supply power to the illumination light source 23 as an electrical connection between the meter part and the pointer part In the pointer driving device, the meter unit includes a light emitting element 21a that photoelectrically converts a control signal for controlling turning on / off of the plurality of illumination light sources 23 into an optical signal and emits the light toward the pointer unit. The pointer portion receives a light signal emitted from the light emitting element 21a, photoelectrically converts the light signal into the control signal, and a control signal photoelectrically converted by the light receiving element 21b. A driver circuit 22 for driving a serial plurality of illumination light sources 23 individually, is characterized by having a.

  Therefore, according to the first aspect of the present invention, the pointer portion and the meter portion are electrically connected with the two poles of the power supply line 32 and the GND line 32, and the lighting / light-off of the illumination light source 23 such as a plurality of LEDs is controlled. By transmitting a control signal to be transmitted as an optical signal between the light emitting element 21a and the light receiving element 21b, the wired part (power feeding) between the pointer part and the meter part is configured with two lines, thereby simplifying the configuration. Can be designed easily. In addition, the length of the pointer can be varied by controlling, for example, all extinction, individual extinction, and full lighting for the plurality of illumination light sources 23 in the pointer portion even with two-pole electrical contact. Can be given.

  The invention according to claim 2 is the invention according to claim 1, further comprising a reflecting member 33 formed in a cylindrical shape around the rotation axis and having the light emitting element 21 a disposed therein, the reflecting member The inner surface of 33 constitutes a reflection surface that allows an optical signal emitted from the light emitting element 21a to be incident on the light receiving element 21b, which is moved by the rotation of the pointer portion, with a light amount of a certain amount or more. Yes.

  Therefore, according to the second aspect of the invention, even if the pointer portion is rotated and the light receiving element 21b is moved by enclosing the outer side of the light emitting element 21a with the cylindrical reflecting member 33 around the rotation axis. The optical communication from the light emitting element 21a of the meter unit is not interrupted.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the illumination light source 23 is PWM driven by the driver circuit 22 based on the control signal transmitted from the meter unit by the optical signal. It is characterized by being.

  Therefore, according to the third aspect of the present invention, the brightness balance can be varied and the fade can be controlled by PWM driving the illumination light source 23 of the pointer portion. In addition, a plurality of illumination light sources 23 having different emission colors are provided in the pointer portion, and an intermediate color can be expressed by controlling the luminance balance of each illumination light source 23.

  According to the first aspect of the present invention, the control signal for controlling turning on / off of the illumination light source such as a plurality of LEDs is electrically connected between the pointer portion and the meter portion with two poles of the power supply line and the GND line, By transmitting an optical signal between the light emitting element and the light receiving element, the wired part (power feeding) between the pointer part and the meter part is configured with two wires, so that the configuration can be simplified and easy Can be designed to In addition, even with two-pole electrical contact, the pointer length can be varied by controlling, for example, all extinction, individual extinction, and full lighting for a plurality of illumination light sources in the pointer section. You can have it.

  According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the pointer portion is rotated by surrounding the rotation axis around the light emitting element with the cylindrical reflecting member. Even if the light receiving element moves, the optical communication from the light emitting element of the meter unit is not interrupted.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, the brightness balance can be varied and the fade control is performed by PWM driving the illumination light source of the pointer portion. You can also. In addition, a plurality of illumination light sources having different emission colors are provided in the pointer portion, and an intermediate color can be expressed by controlling the luminance balance of each illumination light source.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

  Fig.1 (a) is sectional drawing in the instruction | indication direction which shows the structure of the self-light-emitting pointer drive device in embodiment of this invention. The self-light emitting pointer driving device includes a meter side and a pointer side. On the meter side, a meter side electronic board 20a on which the light emitting element 21a is mounted and a stepping motor 31 are provided. On the pointer side, a light receiving element 21b, a pointer side electronic board 20b on which a driver circuit 22 is mounted, and a pointer receiving member 12 having a cylindrical shaft are provided. The pointer receiving member fixes the pointer 10 and the LED 23. The LED 23 is connected to the pointer-side electronic board 20b. The pointer side electronic substrate 20b, the pointer receiving member 12, the LED 23, and the fixed side portion of the pointer 10 are covered with the pointer cap 11.

  Between the meter side and the pointer side, a dial 7 having a portion corresponding to the pointer-side electronic board 20b is provided. A cylindrical reflecting member 33 is provided at the end of the cut dial 7 to enclose the space between the pointer-side electronic board 20b and the meter-side electronic board 20a.

  On the meter side and the pointer side, the rotating shaft of the stepping motor 31 and the columnar shaft of the pointer receiving member 12 are fitted and coupled. A hairspring 32 is disposed around the fitting portion.

  The stepping motor 31 is a motor that rotates by a certain angle upon input of a pulse signal, and the rotation angle can be adjusted according to the number of input pulse signals. Note that the motor for rotating the pointer 10 is not limited to the stepping motor 31, but the configuration can be simplified in that feedback control is not required.

  The pointer 10 rotates according to the rotation angle of the stepping motor 31 and displays a measurement amount such as a speed and a remaining amount of fuel in association with a scale and an index attached to the dial 7. The pointer 10 is in a light emitting state when the LED 23 is turned on. A plurality of LEDs 23 can be provided. In that case, different colors can be provided. Details of the LED 23 will be described later. The hairspring 32 is a fine metal wiring for supplying power from the meter side to the pointer side. Two hairsprings 32 are provided for the power line and the GND line. An FPC (flexible printed wiring) may be used instead of the hairspring 32.

  As the light emitting element 21a, it is preferable to use an infrared light emitting diode or the like that emits invisible light that does not require countermeasures against light leakage to the dial 7. A plurality of light emitting elements 21a may be provided on the meter side electronic substrate 20a. The light emitting element 21a is controlled by a microcomputer 24 (not shown) mounted on the meter side electronic board 20a.

  As the light receiving element 21b, a photodiode, a phototransistor, a Cds cell, or the like may be used. The light receiving element 21b may be provided at a position facing the light emitting element 21a, and a plurality of light receiving elements 21b may be provided on the pointer-side electronic substrate 20b. The light receiving element 21b is controlled by a driver circuit 22 mounted on the terminal side electronic substrate 20b.

  The microcomputer 24 receives a speed signal or the like from the outside, generates a corresponding pulse signal, and drives the stepping motor 31. Moreover, in order to perform light emission control of the pointer 10 through the LED 23, a communication function with the driver circuit 22 is provided, and a communication signal is output from the built-in communication interface to the light emitting element 21a. The driver circuit 22 also has a communication function with the microcomputer 24, and takes in a communication signal detected by the light receiving element 21b from a built-in communication interface. Further, the LED 23 is controlled based on the communication signal.

  The inner surface of the cylindrical reflecting member 33 is a reflecting surface that reflects the light emitted from the light emitting element 21a. When the communication sensitivity between the light emitting element 21a and the light receiving element 21b is necessary, the reflective surface may be subjected to processing such as aluminum vapor deposition.

  FIG.1 (b) is sectional drawing which looked at the meter side light emission surface of the self-light-emitting pointer drive device in embodiment of this invention from the top view. FIG.1 (c) is sectional drawing which looked at the pointer side light-receiving surface of the self-light-emitting pointer drive device in the embodiment of the present invention from above. As shown in FIG. 1B, the light emitting element 21a emits light with a certain range of angles (directivity angle). The light emitted at a certain angle is repeatedly reflected by the inner reflection surface of the reflection member 33 and reaches the lower surface of the pointer-side electronic substrate 20b as shown in FIG. The light emitting element 21a uses a wide-angle element so that the emitted light can reach the entire lower surface of the pointer-side electronic substrate 20b.

  Since light reaches the entire lower surface of the pointer-side electronic substrate 20b, stable communication is possible even when the pointer 10 rotates and the light receiving element 21b rotates. Therefore, the light emitted from the light emitting element 21a is reflected directly or on the inner reflection surface of the reflecting member 33 and is incident on the light receiving element 21b.

  Next, a circuit configuration of the self-light emitting pointer driving device in the embodiment of the present invention will be described. FIG. 2 is a circuit diagram of the self-luminous pointer driving device in the embodiment of the present invention. The circuit comprises a meter (main) side electronic board 20a and a pointer side electronic board 20b. These electronic substrates 20a and 20b are electrically connected by two hairsprings 32 (for power supply lines and for GND lines).

  A microcomputer 24, an inverter 25, a switch element 26, a light emitting element 21a, and a resistor R1 are disposed on the main-side electronic board 20a. A driver IC 22, a light receiving element 21b, and a resistor R2 are disposed on the pointer-side electronic substrate 20b.

  The microcomputer 24 outputs a digital (binary) communication signal from a built-in communication interface in order to transmit a signal for controlling the LED 23 to the driver IC 22. The inverter 25 inverts the communication signal and applies it to the trigger of the switch element 26. The switch element 26 may be a transistor, an FET, or the like.

  The switch element 26 is turned on / off according to the Hi level / Lo level signal of the inverter 25. When the switch element 26 is on, a current flows through the resistor R1 and the light emitting element 21a, and the light emitting element 21a emits light. The resistor R1 is for adjusting the current flowing through the light emitting element 21a. The light emitted from the light emitting element 21 a is a digital signal corresponding to ON / OFF of the switch element 26.

  The light receiving element 21b (a phototransistor in FIG. 2) turns on when detecting light emitted from the light emitting element 21a. The communication interface of the driver IC 22 receives a voltage (Hi level) via the resistor R2 when the light receiving element 21b is turned off, and inputs a GND level (Lo level) when the light receiving element 21b is turned on.

  Therefore, if the inverter 25 is not provided, the communication signal output from the communication interface of the microcomputer 24 and the reverse signal of Hi / Lo are input to the communication interface of the driver IC 22. Therefore, although the inverter 25 is installed in FIG. 2, the inverter 25 can be omitted if an inverted signal is generated and output in the microcomputer 24.

  The driver IC 22 decodes the communication signal input from the communication interface and controls the LED 23. FIG. 2 shows an example in which a plurality of LEDs 23 are installed in the pointer 10. The LED 23 group is connected to a power line. Each LED 23 is wired to connect to the GND line of the driver IC 22. A switch element is connected to each wiring from each LED 23 to the GND line. The switch element may be provided as a semiconductor element in the driver IC 22.

  The driver IC 22 decodes the communication signal and controls on / off of each switch element. In addition, it is possible to adjust the brightness and reduce the power consumption by driving each switch element with a duty by PWM control. Thus, even when a plurality of LEDs 23 are installed, each LED 23 can be independently controlled to adjust the light emission state of the pointer 10.

  FIG. 3 is an external view showing an embodiment in which a plurality of LEDs are arranged in the pointer. FIG. 3A is a top view of the pointer 10 in which a plurality of LEDs 23 are arranged, and FIG. 3B is a side view. The LED 23 group is supplied with power from a power line (not shown). Each LED 23 is connected to the GND line via a switch element (not shown). Lights when the switch element is turned on, and turns off when the switch element is turned off. In this way, since each LED 23 can be turned on / off, it is possible to perform control such as full turn-off, individual turn-off, full turn-on, and individual brightness balance variable.

  For example, it is possible to perform level display such as lighting an arbitrary number of LEDs 23 from the right end in accordance with measurement data such as speed input from the outside to the microcomputer 24. It is also possible to create the pointer 10 that displays intermediate colors by arranging LEDs 23 of different colors (for example, red and green) alternately and performing PWM control on each of them.

  FIG. 4 is a cross-sectional view showing an embodiment in which two LEDs are provided in the pointer. 4A is a top view of the pointer 10, and FIG. 4B is a cross-sectional view taken along line AA in FIG. 4A. The pointer 10 includes two LEDs 23 (for example, red and blue) of different colors and illuminates the light guide path 15 partitioned by the partition plate 13. These are covered with a cover 17, and the cover 17 has a slit 15 for exposing the light guide path 15.

  In addition, even when the diffusion plate 16 for diffusing the light of the light guide path 15 is provided and only one LED 23 is lit, a sufficient amount of light can be extracted from the slit 15. A hot stamp 18 is provided on the surface opposite to the diffusion plate 16, and the light diffused by the diffusion plate 16 is emitted in the direction of the slit 15. By individually controlling the LEDs 23 in the pointer 10 including variable control of the duty ratio, intermediate colors can be expressed.

  The above-described embodiment shows an example of a preferred embodiment of the present invention, and the present invention is not limited thereto, and various modifications can be made without departing from the scope of the invention.

  For example, three LEDs 23 of red, green, and blue may be installed in the pointer 10 as shown in FIG. 4 and individually controlled. By installing the three primary color LEDs 23, a desired emission color can be generated.

It is sectional drawing which shows the structure of the self-light-emitting pointer drive device in embodiment of this invention. It is a circuit diagram of the self-light emitting pointer driving device in the embodiment of the present invention. It is an external view which shows the Example which has arrange | positioned multiple LED in the pointer | guide. It is sectional drawing which shows the Example which provided two LED in the pointer | guide.

Explanation of symbols

7 Dial 10 Pointer 11 Pointer cap 12 Pointer receiving member 20a Meter side electronic board 20b Pointer side electronic board 21a Light emitting element 21b Light receiving element 22 Driver circuit 23 LED (lighting source for illumination)
31 Stepping motor 32 Hairspring 33 Reflective member

Claims (3)

A plurality of illumination light sources, a pointer portion that emits light by turning on at least one of the illumination light sources, a meter portion that rotatably supports the pointer portion by a rotation shaft, and between the meter portion and the pointer portion A self-luminous pointer driving device having a power line and a GND line for supplying power to the illumination light source as electrical contact,
The meter unit is
A light-emitting element that photoelectrically converts a control signal that controls turning on / off of the plurality of illumination light sources into an optical signal and emits the light toward the pointer part;
The pointer part is
A light receiving element that receives an optical signal emitted by the light emitting element and photoelectrically converts the optical signal into the control signal;
A driver circuit for individually driving the plurality of illumination light sources based on a control signal photoelectrically converted by the light receiving element;
A self-luminous pointer driving device characterized by comprising: A reflection member that is formed in a cylindrical shape around the rotation axis, and in which the light emitting element is disposed;
The inner surface of the reflecting member is
2. The reflecting surface according to claim 1, wherein a reflecting surface is provided for allowing an optical signal emitted from the light emitting element to be incident on the light receiving element that is moved by the rotation of the pointer portion with a light amount of a predetermined amount or more. Luminous pointer drive device.   3. The self-luminous pointer driving device according to claim 1, wherein the illumination light source is PWM-driven by the driver circuit based on the control signal transmitted from the meter unit by the optical signal.

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