JP2812386B2 - LED traffic light - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LED traffic light, and more particularly, to an LED traffic light in which LED elements are connected in a matrix.

[0002]

2. Description of the Related Art Traffic lights for vehicles and for walking are required to have high reliability in order to ensure the safety of running of vehicles and traffic of pedestrians. That is, it is strongly required that the lighting state is not affected by a failure, disconnection, short circuit, or the like of the device. In recent years, LED-type traffic signal lights have been used for reasons such as long life. In such an LED type traffic signal light, there are mainly two modes of an LED failure mode, an open (disconnection) mode and a short (short circuit) mode. Of these, the frequency of occurrence of the failure is overwhelming. There are many open modes.

FIG. 5 shows a circuit diagram of a conventional general LED type traffic signal light. As shown in FIG.
In the ED traffic signal light, a parallel circuit 9 is formed by connecting a plurality of series lines in which a plurality of LEDs and a plurality of resistors are connected in series. One end of the parallel circuit 9 is connected to the AC voltage input terminal 7 via the diode bridge circuit 8, and the other end is grounded. And
An AC voltage supplied from an AC voltage power supply (not shown) to the AC input terminal 7 is converted into a DC voltage by the diode bridge circuit 8, and the converted DC voltage is supplied to the anode of each LED of the parallel circuit 9. , LEDs emit light, and a signal lamp is displayed.

[0004]

However, in the conventional traffic signal light shown in FIG. 5, when the above-described open mode failure occurs, the brightness of the signal light significantly decreases. was there. In particular,
For example, in the parallel circuit 9, when even one of the LEDs included in the serial line is disconnected, the disconnected L
Since no current is supplied to all the LEDs in the series line including the ED, all the LEDs in the series line are extinguished, and the brightness of the signal lamp as a whole decreases.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide an LED type traffic signal light capable of stably lighting a signal light regardless of an LED failure. And

[0006]

SUMMARY OF THE INVENTION The LED traffic light of the present invention comprises a plurality of LED blocks each having a plurality of LED elements connected in a matrix and connected in parallel.
The above problem is solved by forming a D block group, applying a voltage signal to the LED block group, causing each of the LED elements included in the LED group to emit light, and displaying a signal light.

That is, the LED traffic signal light of the present invention comprises:
By connecting a plurality of LED elements to each other in a matrix
An ED block is formed, and a plurality of the LED blocks are connected in parallel to form an LED block group.
A voltage signal is applied to the D block group, and each of the LED elements included in the LED block group is caused to emit light to display a signal light.

Accordingly, it is an object of the present invention to provide an LED type traffic signal light capable of lighting a signal light having a stable brightness irrespective of an LED failure.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 to FIG. 4 are views showing an embodiment of an LED type traffic signal light to which the present invention is applied.

FIG. 1 is a diagram showing an external configuration of an LED type traffic signal light according to the present embodiment. The LED traffic light 1 shown in FIG. 1 is used for vehicles. This LED
The traffic light 1 is composed of a signal light 2 and a pole 3. The signal light 3 is connected above the pole 3, and the lower end of the pole 3 is fixed to the ground. The signal light unit 2 includes, in order from the right, R signal lights 2
An R, Y signal light 2Y and a G signal light 2G are arranged.

FIG. 2 is a diagram showing an example of a circuit configuration of the signal light section 2 of the LED traffic light 1 of FIG. The signal light circuit shown in FIG. 2 is configured separately for each of the signal lights 2R, 2Y, and 2G. As shown in FIG. 2, the signal light circuit has three Ls.
The ED blocks B1 to B3 are connected in parallel to form an LED block group B. One end of the LED block group B is connected to an AC input terminal 5 via a diode bridge circuit 6, and the other end is grounded. ing.

Each of the LED blocks 1B to 3B is an equivalent circuit. The LED block 1B includes the LED 1Di, j
Are connected in a matrix. Where i
Indicates a row and j indicates a column, and i = 1 to 7, and j = 1 to 30.
That is, in the 1B LED block, 1Di, 1
The anode side of the LED of ~ 1Di, 30 is serially connected in order, and a resistor R2 is serially connected to the terminal.
And 1D1,1 ~ 1D1,30,1D2,1 ~ 1D2,30, ...
... Each row line of 1D7, 1 to 1D7, 30 is connected to adjacent row lines to form a matrix circuit.

Similarly, the 2B and 3B LED blocks are
LEDs of 2D1,1 to 2D7,30 and 3D1,1 to 2D7,30 are connected in a matrix.

Next, the operation will be described. When an AC voltage is input from an AC power supply (not shown) to an AC input terminal 5 and is converted to a DC voltage by a diode bridge circuit 6 and the converted DC voltage is supplied to the LED block group B, each LED block 1B LED (1
D1,1 to 1D7,30,2D1,1 to 2D7,30,3D1,1 to 3D
7, 30) emit light, and signal lights are displayed.

Next, the operation in the case where there is a failure in the open mode of the LED and the case where there is a failure in the short mode will be described.

First, the operation when an open mode failure occurs will be described. For example, in FIG.
Is disconnected, only the one LED is extinguished, and the other LEDs remain lit. That is, in the present embodiment, since the LEDs are arranged in a matrix, in the row line including the disconnected LED, current is also supplied from the upper or lower row line to the subsequent LED of the disconnected LED, The latter LED has no effect. Specifically, for example, the LED block 1
If the 1D2,3 LED is cut off at D, this 1D
Since only a few LEDs are extinguished and the other LEDs are supplied with current and turned on, they do not affect the brightness of the signal lamp as a whole.

On the other hand, in the conventional circuit shown in FIG. 5, as described above, one of the serially connected LEDs is used.
When a book is disconnected, no current is supplied to all the LEDs on the line including the disconnected LED, so that all the LEDs on this line are extinguished, and the brightness of the signal lamp decreases.

Therefore, in the signal lamp circuit of the present embodiment, the influence of the lighting state due to the failure of the open mode of the LED is reduced as compared with the conventional circuit shown in FIG. 5, and the reliability is improved. Can be.

Next, the operation when a short-mode failure occurs will be described. For example, in FIG.
When D is short-circuited, the impedance of the short-circuited LED becomes substantially zero, and current flows intensively to this short-circuited LED.
No current is supplied to the other LEDs in the column line containing the ED, so that the column line containing the shorted LED goes out. Further, since the LED of each line at the subsequent stage is supplied with current, it is not affected at all. Specifically, for example, LED
In the block 1D, when the 1D2,3 LED is short-circuited, the LED (1D1,3, 1D2,3, 1D3,3,1D) of the column line of the LED block 1D including the 1D2,3 LED is shorted.
4,3, 1D5,3, 1D6,3, and 1D7,3) are only turned off, and the other LEDs are supplied with current and turned on.
Does not affect the brightness of the signal light as a whole.

On the other hand, unlike the present embodiment,
If all the LEDs are configured in a matrix without dividing the LED matrix circuit into each block, 1
If all the LEDs are short-circuited, all the column lines including the short-circuited LEDs are extinguished.

That is, the signal lamp circuit of the present embodiment can cope with both open mode and short mode failures of the LED. In the signal lamp circuit of the present embodiment, the number of serial connections and the number of parallel connections in one block are LE
It is set appropriately according to the open / short fault ratio of the fault mode of D. For example, when there are many failures in the open mode, the number of serially connected LEDs (the number of LEDs included in each row line) in the block is larger than the number of parallelly connected LEDs (the number of LEDs included in each column). do it. On the other hand, if there are many short mode failures,
What is necessary is just to make the number of parallel connections of LEDs larger than the number of serial connections.

FIG. 3 is a diagram showing an example of an arrangement of LEDs of a normal lamp of a signal lamp. In the figure, ○ indicates an LED, and the LEDs are arranged concentrically, and the number of LEDs corresponds to the number in FIG. FIG. 4 is a diagram showing an example of the arrangement of the LEDs of the arrow lights of the signal light device. In the figure, ○ indicates an LED, and this arrow light is an example in which a right arrow is displayed.

As described above, the LE of the present embodiment is
The D-type traffic signal light connects a plurality of LED elements to each other in a matrix to form an LED block.
Since a plurality of the LED blocks are connected in parallel to form an LED block group, a voltage signal is applied to the LED block group, and each of the LED elements included in the LED block group emits light to display a signal light. It is possible to cope with both open mode and short mode failures of the LED, and to provide an LED traffic signal light capable of stably lighting the signal light regardless of the failure of the LED.

In the above embodiment, the LE
Although an example of a D-type traffic signal light for a vehicle has been described, the present invention is not limited to this, and it goes without saying that the present invention may be applied to a traffic light for walking.

[0025]

According to the LED traffic light of the present invention, it is possible to cope with both the open mode and short mode failures of the LED, and to stably turn on the signal light regardless of the LED failure. It is possible to provide a signal light.

[Brief description of the drawings]

FIG. 1 is an external configuration diagram of an LED traffic signal light according to an embodiment.

FIG. 2 is a diagram showing a circuit configuration of a signal light section of the LED traffic light of FIG. 1;

FIG. 3 is a diagram showing an LED layout of a signal light, part 1;

FIG. 4 is an LED layout diagram of a signal light, part 2;

FIG. 5 is a diagram showing a circuit configuration of a conventional LED traffic signal light.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LED type traffic signal light 2 Signal light 3 Pole part 5 AC input terminal 6 Diode bridge circuit 1Di, j ~ 3Di, j LED 1B ~ 3B LED block B LED block group

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-49666 (JP, A) JP-A-59-194299 (JP, A) JP-A-7-287043 (JP, A) 295576 (JP, A) JP-A-7-85377 (JP, A) JP 3-9102 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) G08G 1/095

Claims (1)

(57) [Claims] A plurality of LED blocks each having a plurality of LED elements connected in a matrix form are connected in parallel to each other.
An LED traffic signal device, comprising: forming an ED block group, applying a voltage signal to the LED block group, causing each of the LED elements included in the LED block group to emit light, and displaying a signal light.