JP6287766B2 - Driving signal and apparatus for vehicle direction indicator and driving method thereof - Google Patents

Description

  The present invention relates to a direction indicator that is attached to the front or rear portion of a vehicle and emits light to inform other vehicles or pedestrians of the direction of the vehicle and the intention of the driver. The present invention relates to a driving circuit and apparatus for driving a flashing device and a driving method.

  In recent years, with the widespread use of LEDs (light emitting diodes), their use in vehicle lamps has increased due to their long life, small size, and low power consumption.

  Therefore, as disclosed in Patent Document 1, a vehicle direction indicator has been proposed in which a plurality of LEDs are arranged in the longitudinal direction and sequentially lit.

  As a circuit configuration for sequentially lighting the LEDs, a method of sequentially lighting individual LEDs according to an output signal of the IC using a dedicated integrated circuit (IC) as shown in Patent Document 2, and Patent Document 3 As shown in FIG. 4, there is a method for realizing sequential lighting by inputting a clock signal generated by an oscillator using an oscillator and a counter, and connecting the LED whose state of the output terminal changes and the LED. Further, the dedicated integrated circuit may be a known microprocessor.

JP 2005-142061 A JP 2005-132256 A JP H09-253323 A

  It is desired that the circuit configuration of the direction indicator that sequentially turns on a plurality of LEDs is low-cost and highly reliable. However, since the conventional drive circuit requires relatively large scale integrated circuit parts or electronic parts such as an oscillator and a counter, there is a problem that the drive circuit is expensive and easily breaks down.

  At the same time, instead of turning on (or turning off) the plurality of LEDs at regular intervals in time, when it is desired to turn on (or turn off) at an arbitrary nonuniform timing, a method using a conventional oscillator and counter Then, since it is necessary to continuously change the oscillation frequency of the oscillator, it is obvious that it is difficult to realize. However, it is conceivable to use a microprocessor for the integrated circuit, but in this case, the cost is further increased.

  Further, the direction indicator is mounted on the circuit board by arranging a plurality of LEDs in the longitudinal direction. In this case, the circuit board has an elongated shape in the longitudinal direction. In this respect, when electrical wiring is connected from the integrated circuit component to all the LEDs, the pattern area of the printed wiring board constituting the circuit board is large, which increases the cost.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and in a direction indicator for sequentially lighting by arranging a plurality of light emitting elements in the longitudinal direction, the drive circuit of the light emitting elements is simply configured to ensure high reliability. At the same time, it is an object of the present invention to achieve low cost by adopting a drive circuit configuration that can be easily mounted on a circuit board on which the light emitting elements are arranged.

The drive circuit unit direction indicator for a vehicle shown in claim 1 of the present invention includes a light emitting element formed comprises a pair of terminals are plural arranged, a plurality of buffer circuit means connected in series in multiple stages, the and a power means comprising a first terminal and a second terminal, the other terminal with one terminal connected to the first terminal of said power supply means in the common light emitting element is the output terminal of the buffer circuit means The plurality of buffer circuit means connected in series insert delay circuit means between the output terminal of the previous stage and the input terminal of the next stage, and the first stage of the multi-stage buffer circuit means is the first stage of the power supply means. The plurality of light emitting elements are sequentially turned on and the plurality of light emitting elements are turned off by switching the level of the second terminal of the power supply means connected to the two terminal side. To do.

  According to the second aspect of the present invention, the current flowing to the light emitting element is limited so that the currents of the respective light emitting elements are substantially matched, and the brightness of the light emitting element is approximately equal to the light emitting element in series. A connected current limiting means is provided.

  According to a third aspect of the present invention, the delay constant of the delay circuit means is set to a different value in each of the plurality of light emitting elements arranged.

  According to the fourth aspect of the present invention, in the vehicular direction indicator in which a plurality of light emitting elements arranged in the longitudinal direction are sequentially turned on, the light emitting elements sequentially adjacent to the light emitting elements that are lighted first at the end. This is a method of driving a vehicular direction indicator in which the time until is turned on is gradually reduced.

According to the invention described in claim 5, wherein the current limiting means is a fixed resistor, diagnosis disconnection, short, and a failure of the buffer circuit means of the light emitting element from the change in the current flowing through said power supply means It is characterized by doing.

  According to a sixth aspect of the present invention, the current limiting means is a constant current circuit means using a semiconductor element.

  According to a seventh aspect of the invention, the delay circuit means is a resistor and a capacitor connected in series.

  According to the invention described in claim 8, a diode is disposed in parallel with the resistor of the delay circuit means.

  According to the invention described in claim 9, the light emitting element is characterized in that at least two or more light emitting elements are arranged in series to form one set, and a plurality of such series of light emitting elements are arranged.

According to the invention described in claim 10, a plurality of light emitting elements arranged in pairs and having a pair of terminals, and a plurality of buffer circuit means connected in series in multiple stages, one of the light emitting elements And the other terminal is connected to each output terminal of the buffer circuit means, and the plurality of buffer circuit means connected in series include an output terminal in the previous stage and an input terminal in the next stage. The delay circuit means is inserted between the inverting buffer circuit means and the inverting buffer circuit means is connected from the output of the last stage of the buffer circuit means connected in series toward the input of the front stage.

According to the first aspect of the present invention, since the plurality of light emitting elements can be sequentially turned on by the plurality of buffer circuit means connected in series, the cost is lower than the conventional method using the integrated circuit component or the counter. In addition, since the circuit configuration is simple, high reliability can be realized.

  In addition, since there is no need for wiring extending from the single integrated circuit component to a plurality of light emitting elements, all electronic components can be easily mounted on a printed wiring board elongated in the longitudinal direction. It is not necessary to enlarge the dimension of the wiring board in the width direction, and the material cost can be suppressed.

  According to the invention of claim 2, since the current flowing to each light emitting element is substantially uniformly restricted by the current limiting means, it is possible to reduce the luminance variation of the plurality of light emitting elements.

  According to the third aspect of the present invention, the lighting timing pattern of the light emitting elements arranged in a row in the longitudinal direction can be arbitrarily set without using a high-performance integrated circuit component such as a microprocessor. Can be set.

  According to the invention of claim 4, the length of the rod-like light source formed by lighting the light emitting elements arranged in a row in the longitudinal direction slowly extends in the initial stage of lighting, and the lighting end portion By performing the speed variable chain lighting that extends at a faster speed as the vehicle approaches, the direction indication recognizability when viewed from outside the vehicle can be increased.

  According to the fifth aspect of the present invention, it is possible to easily diagnose a failure state of a vehicular direction indicator that sequentially lights a plurality of light emitting elements arranged in the longitudinal direction without adding a dedicated component.

  According to the sixth aspect of the present invention, the luminance unevenness of the plurality of light emitting elements can be reduced at a higher level, so that the quality of the lighting state can be improved.

  According to the invention of claim 7, it is possible to realize a drive circuit device for sequentially lighting the light emitting elements at a low cost, and an arbitrary chain lighting pattern can be easily created by setting constants of resistors and capacitors.

  According to the invention of claim 8, in the signal transmission requirement from the arbitrary position of the plurality of buffer circuit means connected in series to the next stage, a combination of simultaneous lighting + delayed-off or delayed lighting + simultaneous-off is free. Since it can be set, an arbitrary chain lighting pattern can be easily created.

  According to the ninth aspect of the present invention, by arranging a plurality of light emitting elements connected in series in the short direction and forming a row in the long direction, the width of the rod-shaped light source can be arbitrarily enlarged. .

  According to the invention of claim 10, only by applying the battery voltage of the vehicle, the light emitting means arranged in the longitudinal direction are sequentially turned on without requiring any special control circuit, and after all the light emitting means are turned on, A series of operations such as turning off all the light emitting means can be automatically repeated.

1 is a drive circuit for a vehicle direction indicator according to the present invention. FIG. 4 is a detailed view of current limiting means and delay circuit delay circuit means. It is another embodiment of the delay circuit means. It is another Example of a current limiting means. It is the figure which compared the circuit board structural drawing of the direction indicator for vehicles of this invention, and the structure by a prior art. It is explanatory drawing of a buffer circuit means. It is another Example in a light emitting element. It is a figure explaining the Example of speed variable chain lighting. It is circuit explanatory drawing which performs a failure diagnosis of the direction indicator for vehicles of this invention. It is the figure explaining the method of failure diagnosis of the direction indicator for vehicles of the present invention. It is a figure explaining operation | movement of a delay circuit means. It is another Example of the direction indicator for vehicles of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a vehicle direction indicator driving circuit and apparatus and driving method thereof according to the present invention will be described below with reference to the drawings.

  Reference numeral 1 in FIG. 1 denotes a driving circuit for a vehicular direction indicator according to the present invention, and terminals T1, T2, and T3 are connected to a vehicle body side circuit 5 expressed in a simplified manner through electrical connection wiring. Reference numeral 51 denotes a power supply obtained by stepping down the vehicle power supply to a constant voltage of, for example, 5V, 52 is a normally closed type direction indicator operation switch, and 53 is a pull-down resistor.

  The drive circuit 1 of the vehicular direction indicator is supplied with power from the terminal T1, and a control signal that is at a low level when the drive circuit 1 is operated is input from the terminal T2. Further, the control signal is inputted to the buffer circuit means 10, and the buffer circuit means 10 is connected in series with 11, 12, and in order up to 1n. It should be noted that delay circuit means 30 to delay circuit means 33 are inserted at the intermediate points connecting the buffer circuit means. Further, the output terminals of the buffer circuit means 10 to the buffer circuit means 1n are connected to the power supply terminal T1 through the LEDs 20 to LED2n and the current control means 40 to the current control means 4n connected in series.

  Here, the number n of the LEDs 20 to 2n, which are the light emitting elements, the luminance, the color tone, and the like are numerical values that should be arbitrarily determined according to the design of the vehicle lighting device, the size of the LED, and the like, and accordingly the buffer circuit means The required number of current control means and delay circuit means is determined.

A suitable example of the buffer circuit means is an XC7SET125 made by NXP, which is a non-inverting C-MOS buffer having an internal logic image shown in FIG. 6, but the configuration of the buffer circuit means is limited to this. Needless to say, discrete type MOSFETs, bipolar transistors and the like can be used.

  Further, in the embodiment of FIG. 1, the LEDs 20 to 2n are arranged between the output of the buffer circuit means 10 to the buffer circuit means 1n and the terminal T1, but the LED is grounded from the output of the buffer circuit means, that is, the terminal T3. It is clear that even if it is placed between the two, it does not depart from the gist of the present invention.

  By operating the direction indicator operation switch in the configuration as described above, when the voltage at the terminal T2 becomes low level and the output terminal of the buffer circuit means 11 becomes low level, the LED 21 is forward biased and the current The current limited by the limiting means 41 is supplied to the LED 21 to be in a lighting state. When the output terminal of the buffer circuit means 11 becomes high level, the bias of the LED 21 is released and the LED 21 is turned off.

  As shown in FIG. 2, the details of the current limiting means include resistors Rd1 to Rdn inserted between the power supply terminal T1 and the LEDs 20 to LED2n. Thus, for example, when the voltage at the power supply terminal T1 is 5V and the output terminal of the buffer circuit means 10 is at a low level, the current flowing through the LED 20 is limited to (5V−the forward voltage drop of the LED 20) ÷ Rd1. Similarly, when the brightness of the LEDs 20 to 2n varies, the values of the resistors Rd1 to Rdn of the current limiting unit 40 to the current limiting unit 4n are appropriately adjusted in advance so that the brightness of the LEDs 20 to 2n is uniform. Adjusted to

  Next, the details of the delay circuit means are shown in FIG. 2, for example, when the delay circuit means 30 is taken as an example, the output terminal of the buffer circuit means 10 is connected to a capacitor Ct1 whose one terminal is grounded via a resistor Rt1. And connected to the input terminal of the buffer circuit means 11 connected to the subsequent stage from the other terminal of the capacitor Ct1. Similarly, the buffer circuit means 11 to buffer circuit means 1n, the resistor Rt2 to the resistor Rt4, and the capacitor Ct2 to the capacitor Ct4 are connected, and the output terminals of the buffer circuit means are sequentially delayed to a low level as shown in FIG. .

  FIG. 11 is a diagram showing the waveforms of the input / output terminal states of the buffer circuit means. When the terminal T2 changes to a low level, the output terminal of the buffer circuit means 10 becomes a low level and the LED 20 lights up. . At the same time, the voltage at the input terminal of the buffer circuit means 11 gradually decreases due to the action of the delay circuit means 30, and is delayed by Td1 when the voltage drops below the input threshold level Vth11 of the buffer circuit means 11, that is, the buffer circuit means 11 The output terminal is inverted to a low level and the LED 21 is lit. Similarly, the LED 22 is turned on with a delay of Td2. Thus, the delay time until the next-stage LED is lit can be freely set according to the set value of the delay circuit means.

  FIG. 8 is a diagram schematically showing the lighting state of the light emitting means, which is formed by lighting the light emitting elements arranged in rows in the longitudinal direction using the setting of the delay circuit means. The light emission length of the rod-shaped light source is as follows: time from 1 to 2 in FIG. 8 until 2 is turned on> time from 2 to 3 is turned on> 3 is lit and 4 is lit In this embodiment, the lighting interval is shortened sequentially, such as the time until the lighting is performed, so that the speed variable chain lighting gradually extends at the beginning of lighting and extends at a higher speed as it approaches the end of lighting.

Thus, the recognition level when the vehicular direction indicator of this embodiment is viewed from the outside of the vehicle is “lighted” to the viewer in a region where the lighting speed is slow, that is, the lighting time of each light emitting means is long. "Attention / danger" can be recognized at the end where the number of lighting of the following light emitting means increases rapidly, so that the direction indication recognizability of this apparatus is enhanced.

  FIG. 3 shows another embodiment of the delay circuit means. Since the configurations of the buffer circuit means 10 to the buffer circuit means 1n, the current limiting means 40 to the current limiting means 4n, and the LED 20 to LED2n are the same as those described above, the description thereof is omitted.

  As an example, a diode Dt1 is connected in parallel with the resistor Rt1 of the delay circuit means 30 in a direction with the buffer circuit means 10 side as an anode. In this case, when a high level signal is input from the terminal T2, the output terminal of the buffer circuit means 10 becomes high level, so that the charging current of the capacitor Ct1 flows through the diode Dt1, and as a result, the capacitor Ct1 The battery is rapidly charged in a short time, and the input terminal voltage of the buffer circuit means 11 immediately becomes a high level.

  Therefore, the LED 20 and the LED 21 are turned off almost simultaneously. Similarly, when the diodes Dt1 to Dt4 are connected in parallel to the resistors Rt1 to Rt4 in the above direction, the turn-off timings of the LEDs 20 to LED2n are substantially the same.

  As described above, by disposing the diodes so that the charging time of the capacitor in the delay circuit means is zero, the light emitting means can be turned off at the same time. The light source by the light emitting means arranged in the longitudinal direction is lit and lighted with time, and all the light emitting means are simultaneously turned on in synchronization with the signal at the terminal T2 becoming high level after all the light emitting means are turned on. It works to turn off the lights.

  On the other hand, since the diode shown in FIG. 2 does not include the diode, the charge / discharge times of the capacitors Ct1 to Ct4 are substantially the same, and a high level signal is input to the terminal T2 after the issuing means is fully lit. Then, LED20-LED2n acts so that it may turn off sequentially.

  Further, in the above embodiment, the LED 20 and the LED 21 are simultaneously turned off by connecting the diode Dt1 to the resistor Rt1 in parallel. However, when the polarity of the diode is reversed, the LED 20 and the LED 21 are turned on simultaneously. Is also possible.

However, the vehicle direction indicator of the present invention can be installed by arranging 10 LEDs in the longitudinal direction and 3 lights from the end at the same time. It is possible to easily realize an arbitrary lighting state in which the tenth to tenth lights are sequentially turned on.
In the above embodiment, a diode connected in parallel with a resistor is used as a means for changing the charge / discharge time of the capacitor. However, as a means for changing the charge / discharge time, the capacitance of the capacitor is changed, or the resistor It should be understood as part of the design matter that the value of the vessel may be changed.

  FIG. 4 shows another embodiment of the current limiting means 40 to the current limiting means 4n. The current limiting means 40 will be described as an example. A constant voltage power source is supplied from the terminal T1, and a predetermined voltage is set by dividing the voltage by the resistors Ra and Rb. The transistor Q inputs such a predetermined voltage to the base, and is connected from the emitter to the constant voltage power source via the resistor Rc. As a result, a constant current of (the predetermined voltage set by the constant voltages −Ra and Rb) ÷ Rc flows through the collector circuit of the transistor Q, and the constant current flows through the LED 20. In this way, the current for lighting the LED 20 is kept constant, and the same configuration is applied to all the LEDs, so that the light emission luminance of all the LEDs 20 to 2n is accurately uniformed.

Next, an apparatus constituted by the driving circuit 1 for a vehicle direction indicator according to the present invention is shown in FIG. 5 (a), and an apparatus constituted by the prior art is shown in FIG. 5 (b) for comparison. .

  Reference numeral 2 in FIG. 5 (a) denotes a vehicular direction indicator device according to the present invention, in which parts corresponding to the circuit numerals in FIGS. 2 and 3 are denoted by the same reference numerals. That is, in the vehicle direction indicator device 2, the light emitting element 20 to the light emitting element 2n are soldered and mounted on one side of a circuit board 100a formed of a printed wiring board elongated in the longitudinal direction. Similarly, the resistor Rd1, the buffer circuit All components such as means 10, diode Dt1, resistor Rt1, capacitor Ct1, etc. are mounted.

  In this way, the device 2 on which the vehicle direction indicator drive circuit 1 according to the present invention is mounted has the components Rd1, 20, 10, Dt1, Rt1, and Ct1 as a group, and all components are included in the circuit board 100a. Since the width of the circuit board 100a can be reduced, the mounting space as a direction indicator for a vehicle is small and an excellent design can be provided. It is.

  On the other hand, the device according to the prior art of FIG. 5B requires a lot of wiring from the single integrated circuit component 200 to the switching elements 201 that drive the light emitting elements 20 and the like. A wiring group 101 with a printed pattern is required on the surface of the substrate 100b. For this reason, since the dimension in the width direction of the circuit board 100b is increased, the material price is increased, the mounting property to the vehicle is poor, and a design problem occurs.

  FIG. 7 shows an embodiment in which the width of the light emitting source is expanded by arranging the light emitting elements 20a and 20b connected in series in the short direction and forming rows 21a to 2na in the long direction. Note that the operation of the drive circuit 1 of this embodiment is the same as that of the above-described embodiment, so that the description thereof is omitted. Even when the light source design has a width in the short direction as in this embodiment, the driving circuit 1 of the vehicle direction indicator of the present invention has an excellent design that is easy to arrange on the circuit board. It is feasible.

  Hereinafter, the failure diagnosis method for the drive circuit 1 of the vehicle direction indicator according to the present invention will be described with reference to FIGS. In FIG. 9, the battery of the vehicle body side circuit 5 expressed in a simplified manner is connected to the constant voltage circuit means 55 via the resistor 54, and the output voltage of the constant voltage circuit means 55 is the drive of the vehicle direction indicator of the present invention. It is connected to the terminal T1 of the circuit 1. Since the operation of the drive circuit 1 is the same as described above, the description thereof is omitted.

  At both ends of the resistor 54, a voltage Vx proportional to the current flowing through the terminal T1 of the drive circuit 1 is generated. As shown in FIG. 10, Vx rises by step 1 when the LED 20 is turned on, and rises by step 2 when the LED 21 is turned on. Similarly, when all the LEDs are sequentially turned on with a delay of a predetermined time, the currents flowing through the respective LEDs 20 to 2n are substantially equal. Therefore, as shown by the broken lines in FIG. To do.

  However, if the LED 23 is disconnected, Vx does not increase at step 4 in FIG. 10A, and Vx increases at step 5, so the waveform is as shown by the solid line. Thus, the disconnection of the LED 23 can be identified from the waveform of Vx.

  Similarly, when the LED 23 is short-circuited, the known forward voltage drop VF of the LED 23 becomes 0 V, so that the current flowing through the terminal T1 increases, as shown in step 4 of FIG. 10B. Vx greatly increases. In this way, the short circuit of the LED 23 can be specified from the waveform of Vx.

  Subsequently, in the failure mode in which the output terminal of the buffer circuit means 13 does not become low level, Vx does not increase after that step as shown in step 4 of FIG. The failure can be identified. On the other hand, in the failure mode in which the output terminal of the buffer circuit means 13 does not go to the high level, Vx remains elevated, so that the failure of the buffer circuit means can be similarly identified.

  Next, another embodiment of the driving circuit 1 for a vehicle direction indicator according to the present invention will be described with reference to FIG. In the above-described embodiments, the driving circuit for a vehicular direction indicator of the present invention has three terminals T1, T2, and T3. However, in this embodiment, two terminals T1 and T2 are provided. It comprises.

  Reference numeral 55 in FIG. 12 denotes constant voltage circuit means 55 built in the drive circuit 1, which is connected to a vehicle-side electric circuit (not shown) via a terminal T1, and for example, 12V is supplied from the battery voltage via a turn signal switch. In addition to being supplied, the current limiting means 40 to the current limiting means 4n act to supply a voltage stabilized at 5V. The delay circuit means includes resistors Rt1 to Rt4, diodes Dt1 to diode Dt4, capacitors Ct1 to capacitor Ct4, and one end of each of the capacitors Ct1 to Ct4 is connected to the output terminal of the constant voltage circuit means 55. Connected. Reference numeral 60 denotes inverting buffer circuit means disposed between the output of the buffer circuit means 1n and the input of the buffer circuit means 10.

  When a voltage of 5V is output from the constant voltage circuit means 55 configured as described above, the initial charges of the capacitors Ct1 to Ct4 of the delay circuit means are 0, so that the buffer circuit means 11 to the buffer circuit means 1n The input voltage is 5V. Accordingly, all the LEDs 20 to 2n are in the off state, but the input voltage of the inverting buffer circuit means 60 is 5V, and therefore the output voltage of the inverting buffer circuit means 60 is 0V.

However, the output voltage of the buffer circuit means 10 becomes a low level and the LED 20 is turned on, and then the LEDs 2n are sequentially turned on with a delay. Then, the input voltage of the inverting buffer circuit means 60 becomes 0 V, the output voltage of the inverting buffer circuit means 60 becomes high level, and then the output voltage of the buffer circuit means 10 becomes high level, and the LED 20 is turned off. To do.

Therefore, the capacitor Ct1 is rapidly charged via the diode Dt1, and the LEDs 21 are also turned off simultaneously, and similarly, all the LEDs 20 to LED2n are turned off simultaneously. Subsequently, the output voltage of the inverting buffer circuit means 60 becomes low level, and the LEDs 20 to 2n are sequentially turned on again.

  As described above, the driving circuit 1 for the vehicular direction indicator according to the present embodiment simply applies the battery voltage of the vehicle to the terminal T1, and does not require a special control circuit. A series of operations can be automatically repeated such that the LEDs are sequentially turned on and all the LEDs are turned on and then all the LEDs are turned off simultaneously.

  As described above, the circuit configuration and device of the vehicular direction indicator according to the present invention, in which a plurality of LEDs are sequentially lit, ensure a high reliability by simplifying the driving circuit of the light emitting element and the light emitting element. By adopting a drive circuit configuration that can be easily mounted on the arranged circuit board, it can be realized at low cost.

Also, the vehicle direction indicator driving method of the present invention allows the viewer to recognize that the lighting speed is low, that is, in a region where the lighting time of each light emitting means is long, and that the light emitting means continues. At the end where the number of lights increases rapidly, it is possible to recognize “caution / danger”, so that there is an effect that the visibility is good and the safety is enhanced.

  The application field of the present invention is not limited to a vehicle direction indicator, but can be applied in various ways as a technique for sequentially lighting a plurality of light emitting means arranged side by side.

DESCRIPTION OF SYMBOLS 1 Vehicle direction indicator drive circuit 2 Vehicle direction indicator device 10, 11, 12, 13, 1n Buffer circuit means 20, 21, 22, 23, 2n, 20a, 20b, 21a, 21b, 22a, 22b 23a, 2na, 2nb LED
30, 31, 32, 33 Delay circuit means 40, 41, 42, 43, 4n Current limiting means 5 Vehicle side circuit 51 Power supply 52 Direction indicator operation switch 53 Pull-down resistor 100a Circuit board 100b Circuit board 200 Integrated circuit 201 Switching element 60 Inversion buffer circuit means

Claims (10)

A plurality of light emitting devices arranged in a plurality of stages, a plurality of buffer circuit means connected in series in multiple stages, and a power supply means having a first terminal and a second terminal, And the other terminal is connected to each output terminal of the buffer circuit means, and the plurality of buffer circuit means connected in series are the output terminals of the previous stage. And delay circuit means between the input terminal of the next stage and
The first stage of the multistage buffer circuit means is connected to the second terminal side of the power supply means,
By switching the level of the second terminal of the power supply means, the plurality of light emitting elements are sequentially turned on and the plurality of light emitting elements are turned off. Drive circuit and device.   A current limiting means connected in series with the light emitting element is provided in order to limit the current flowing to the light emitting element so that the currents of the light emitting elements are substantially the same, and the luminance of the light emitting element is substantially uniform. The driving circuit and device for a vehicular direction indicator according to claim 1.   3. The drive circuit and device for a vehicular direction indicator according to claim 1, wherein a delay constant of the delay circuit means is set to a different value in each of the plurality of light emitting elements arranged.   2. The direction indicator for a vehicle according to claim 1, wherein the plurality of light emitting elements arranged in the longitudinal direction are sequentially turned on, and the time from the light emitting element that is first turned on at the end to the time when the adjacent light emitting elements are turned on is gradually reduced. A driving method of a vehicular direction indicator characterized by having been made. Before SL current limiting means is a fixed resistor, according to claim 2, wherein the diagnosing faults of disconnection, short, and the buffer circuit means of the light emitting element from the change in the current flowing through said power supply means Drive device and device for a vehicle direction indicator. 3. The vehicle direction indicator driving circuit and apparatus according to claim 2 , wherein the current limiting means is a constant current circuit means using a semiconductor element.   7. The vehicle direction indicator driving circuit and device according to claim 1, wherein the delay circuit means is a resistor and a capacitor connected in series. .   8. The vehicle direction indicator drive circuit and apparatus according to claim 7, wherein a diode is disposed in parallel with the resistor of the delay circuit means.   6. The light emitting device according to claim 1, wherein at least two or more light emitting devices are arranged in series, and a plurality of such light emitting device groups are arranged. Item 9. The driving circuit and device for a vehicle direction indicator according to Item 8. A plurality of light emitting elements arranged with a pair of terminals and a plurality of buffer circuit means connected in series in multiple stages, and one terminal of the light emitting elements is connected in common to the power supply means The other terminal is connected to each output terminal of the buffer circuit means, and the plurality of buffer circuit means connected in series insert delay circuit means between the output terminal of the previous stage and the input terminal of the next stage,
A drive circuit and device for a vehicular direction indicator, wherein an inverting buffer circuit means is connected from an output of a last stage of the buffer circuit means connected in series toward an input of a front stage.

Images