JP2010165083A - Display device and fault detection method for display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably determine whether an LED (light emitting diode) is faulty or normal without enlarging a device circuit. <P>SOLUTION: The display device is provided with: a parity calculation means 3 for, when displaying the state by inputting input signals 2a to 2n to a plurality of LEDs 1a to 1n to turn on the LEDs, calculating a parity to turn on odd-number (or even-number) of the LEDs 1a to 1n based on the input signals 2a to 2n ; and a parity LED 4 for displaying the calculation result of the parity calculation means 3. The display device detects the faults of the LEDs 1a to 1n based on the total number of the turned-on LEDs 1a to 1n and the number of the turned-on parity LED 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device using an indicator lamp composed of an LED (light emitting diode) or the like, and more particularly to a display device capable of detecting a failure of the indicator lamp and a failure detection method of the display device.

  In a conventional computer or the like, status display or setting display is performed using a display device. In addition, since an apparatus that performs system monitoring, display, alarm, or control is required to operate continuously, an operation state or the like is displayed by a display device.

  In the computer and apparatus as described above, high reliability is required for the status display and setting display by the display device. As a conventional failure detection mechanism, the presence or absence of a failure is achieved by multiplexing the switches in the on / off sensor. Has been detected to improve reliability (see Patent Document 1).

JP 09-005125 A

  When the failure detection mechanism disclosed in Patent Document 1 is applied to a display device, there is a problem that the device circuit becomes large by multiplexing the indicator lamps. In addition, for example, even if a certain indicator light fails and remains off, there is a problem that it is not possible to distinguish whether the indicator light is out of order and whether the current state is off. It was.

  The present invention has been made to solve the above-described problems, and can provide a display device and a display device that can reliably distinguish between a failure state and a normal state of an indicator light without increasing the size of the device circuit. An object of the present invention is to provide a failure detection method.

  The display device according to the present invention performs status display by inputting an input signal to a plurality of indicator lamps and lighting them, and the number of indicator lamps to be lit by the input signal is an odd number (or an even number). Parity calculating means for calculating the parity and a parity indicator for displaying the calculation result by the parity calculating means are provided, and the indicator lamp is based on the total number of the lit indicator lights and the lit parity indicator lights. It is intended to detect the failure of the.

  The display device failure detection method according to the present invention includes a step of calculating parity in which the number of indicator lamps to be turned on is odd (or even) by an input signal input to a plurality of indicator lamps, and a parity calculation result. This comprises steps of detecting a failure of the indicator lamp based on the total of the number of indicator lamps lit and the number of lit parity indicator lights.

  According to the display device of the present invention, an input signal is input to a plurality of indicator lamps to perform status display and the like, and the number of indicator lamps to be lit by the input signal is an odd number (or even number). Parity calculation means for calculating the parity to be and a parity indicator lamp for displaying the calculation result by the parity calculation means, and based on the total number of lit indicator lights and lit parity indicator lights Since the failure of the indicator lamp is detected, the failure state and the normal state of the indicator lamp can be accurately distinguished without increasing the size of the apparatus.

  Further, according to the failure detection method of the display device according to the present invention, the step of calculating the parity in which the number of the indicator lamps to be turned on is odd (or even) by the input signals input to the plurality of indicator lamps, and the parity calculation The result is displayed on the parity indicator lamp, and it consists of the step of detecting the indicator lamp failure based on the total number of indicator lamps that are lit and the number of parity indicator lights that are lit. In addition, it is possible to accurately distinguish between a failure state and a normal state of the indicator lamp.

It is a block block diagram which shows the internal structure of the display apparatus by Embodiment 1 of this invention. It is a block block diagram which shows the internal structure of the display apparatus by Embodiment 2 of this invention. It is a table | surface which shows an example of an output pattern. It is a block block diagram which shows the internal structure of the display apparatus by Embodiment 3 of this invention.

Embodiment 1 FIG.
1 is a block diagram showing the internal structure of a display device according to Embodiment 1 of the present invention. In the present invention, a case where an LED (light emitting diode) is used as the indicator lamp will be described.

  In the figure, the display device is the sum of the number of LEDs 1a to 1n that perform status display, the input signals 2a to 2n that are input to the LEDs 1a to 1n, and the LEDs 1a to 1n that are lit based on the input signals 2a to 2n. Has a parity calculation means 3 for calculating a parity with an odd number (or even number), and a parity LED (parity indicator lamp) 4 for displaying a calculation result of the parity calculation means 3. The parity calculation is based on the odd number, that is, the parity is 0 when the total number of lit LEDs is odd, and the parity is 1 when the number is even. May be used as a reference.

  The LEDs 1a to 1n are turned on based on the input signals 2a to 2n, and state display is performed according to the lighting states of the LEDs 1a to 1n. The parity calculation means 3 calculates the parity by the total number of LEDs 1a to 1n that are turned on by the input signals 2a to 2n, and displays the calculation result on the parity LED 4.

  For example, when the number of lit LEDs 1a to 1n is 4, since the number is even, the calculation result of the parity calculation means 3 is 1, and the parity LED 4 is lit. When the number of lit LEDs is 3, the calculation result of the parity calculation means 3 is 0, and the parity LED 4 is not lit.

  When one LED to be lit fails, the sum of the number of lit LEDs and the number of lit parity LEDs 4 is an even number, and the failure of the LEDs 1a to 1n can be detected. For example, when the number of LEDs that are not broken and should be lit is four and the parity LED 4 is in a lit state, when one of the four lit LEDs fails, three LEDs Will light up. On the other hand, since the input signals 2a to 2n are normally input to the parity LED 4, the LED 1a is turned on, and the sum of the number of lit LEDs and the number of turned on parity LEDs 4 is 4, that is, an even number. It is possible to detect that any of ˜1n has failed.

  Although the case where one of the LEDs 1a to 1n has failed has been described above, the failure can be detected even when an odd number (for example, three) other than one has failed. However, it cannot be specified which of the LEDs 1a to 1n has failed, and the failure cannot be detected when an even number of the LEDs 1a to 1n has failed or when an unlit LED has failed.

Embodiment 2. FIG.
2 is a block diagram showing the internal structure of a display device according to Embodiment 2 of the present invention. In the present embodiment, an LED diagnostic unit 11 and a diagnostic button 12 for operating the LED diagnostic unit 11 are provided. In the first embodiment, when the unlit LEDs 1a to 1n fail or when two (even) of the lit LEDs 1a to 1n fail, the failure of the LEDs 1a to 1n is detected. However, in the present embodiment, since the LED diagnosis means 11 is provided, the failure of the LEDs 1a to 1n can be detected even in such a case.

  When the LED diagnosis unit 11 depresses the diagnosis button 12, not the input signals 2a to 2n but the output pattern output from the LED diagnosis unit 11 is input to the LEDs 1a to 1n to light the LEDs 1a to 1n. The failure of the LEDs 1a to 1n can be detected by checking the sum of the number of lit LEDs and the number of lit parity LEDs 4 based on the output pattern of the LED diagnosis means 11.

  Next, an example of an output pattern that can detect a failure even when an even number (for example, two) of the LEDs 1a to 1n fails will be described below. As an example, a case will be described in which two LEDs 1a and 1d out of five LEDs 1a to 1e are out of order and three output patterns A, B, and C are prepared as output patterns.

  FIG. 3 is a table showing the correlation between the output patterns A, B and C and the LEDs 1a to 1e and the parity LED 4. In the figure, the LED diagnosis means 11 first outputs an output pattern A for turning on the LEDs 1a and 1b. .

  At this time, since a signal for turning on the two LEDs is input to the parity calculating means 3, the parity LED 4 is turned on, but since the LED 1a has failed, only the LED 1b is turned on, and therefore the light is turned on. Since the sum of the LED being turned on and the parity LED 4 being lit is 2, which is an even number, it is possible to detect that one of the LED 1a and the LED 1b has failed.

  Next, the LED diagnosis unit 11 outputs an output pattern B for turning on the LEDs 1b and 1c. At this time, since the signal for turning on the two LEDs is input to the parity calculating means 3, the parity LED 4 is turned on and the LEDs 1b and 1c are turned on, so that the LEDs that are turned on are turned on. The total number of the parity LEDs 4 is 3, which is an odd number, so that it can be detected that it is normal.

  Next, the LED diagnosis unit 11 outputs an output pattern C for lighting the LEDs 1c and 1d. At this time, since the signal for turning on the two LEDs is input to the parity calculating means 3, the parity LED 4 is turned on, but since the LED 1d is out of order, only the LED 1c is turned on. The sum of the LED being turned on and the parity LED 4 being turned on is 2, which is an even number, so that it is possible to detect that the LED 1d has failed. Therefore, if such output patterns A, B, and C are output, the failure can be detected even if an even number of LEDs fail. In addition to the output patterns A, B, and C as described above, various output patterns can be considered.

Embodiment 3 FIG.
4 is a block diagram showing the internal structure of a display device according to Embodiment 3 of the present invention. In the present embodiment, a test apparatus 21 and a test apparatus communication means 22 are provided. In the second embodiment, the case where the failure of the LEDs 1a to 1n is detected by the output pattern output from the LED diagnosis unit 11 is shown. However, in the present embodiment, the test device 21 is connected via the test device communication unit 22. By connecting, a desired output pattern is input from the test apparatus 21 to the LEDs 1 a to 1 n and the parity calculation means 3.

  When the test apparatus 21 is connected to the test apparatus communication means 22, not the input signals 2a to 2n but the output pattern output from the test apparatus 21 is input to the LEDs 1a to 1n, and the LEDs 1a to 1n are turned on. By inputting a desired output pattern from the test apparatus 21 to the LEDs 1a to 1n and checking the sum of the number of lighting of the LEDs 1a to 1n and the number of lighting of the parity LEDs 4, the failure of the LEDs 1a to 1n can be detected. A specific example of the output pattern is the same as that shown in the second embodiment.

  In the second embodiment, by operating the diagnostic button 12, only a predetermined output pattern can be output from the LED diagnostic means 11, but according to the present embodiment, it is necessary for the test apparatus 21. The output pattern can be selected, and the output pattern can be diversified.

1a to 1n LED, 2a to 2n input signal, 3 parity calculation means,
4 Parity LED.

Claims (2)

  Parity calculating means for calculating parity in which the number of the indicator lamps to be lit by the input signal is an odd number (or even number) in a display device that displays a status by inputting and lighting the input signals to a plurality of indicator lights And a parity indicator lamp for displaying a calculation result by the parity calculating means, and the failure of the indicator lamp is determined based on the total number of the indicator lamps that are lit and the number of parity indicators that are lit. A display device characterized by detecting. Calculating a parity in which the number of the indicator lamps to be turned on by an input signal input to a plurality of indicator lamps is an odd number (or an even number);
A display device comprising a step of displaying the parity calculation result on a parity indicator lamp, and detecting a failure of the indicator lamp based on the total number of the indicator lamps that are lit and the number of parity indicators that are lit. Failure detection method.

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