JP2009112074A - Power failure display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power failure display which informs a user of power failure precisely in a simple structure. <P>SOLUTION: In the case where a voltage monitoring circuit 1 detects a normality, the output of a photocoupler 2 becomes short, and a current from a resistor 4 flows to the photocoupler 2. An LED 3 is then turned off (normal). A digital transistor 5 is also turned off, which informs a user of the normality. In case the voltage monitoring circuit 1 detects an abnormality, the output of the photocoupler 2 is opened, and a current from the resistor 4 flows to the LED 3, and indicates the abnormality. A current also flows to the digital transistor 5, and it is turned on, and informs the outside of the abnormality. When a mask signal to direct its power off, the transistor 6 is turned on, and even if the output of the photocoupler 2 is open, the current from the resistor 4 flows to the transistor 6. By this action, the current does not flow to the LED 3, and it is turned off (normal). The digital transistor 5 is also turned off, which informs the user of the normality. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power failure display device that displays a power failure.

  The power supply device is provided with a voltage monitoring circuit for monitoring a power supply failure. This voltage monitoring circuit is connected to the output voltage of the power source, and has a function of detecting an overvoltage and a voltage drop and notifying the outside of the failure.

  Since such a voltage monitoring circuit is provided for each output voltage, the number of applications is large. Therefore, when the power supply fails, a display device is provided for each output voltage so as to identify the failure for each output voltage, and the failed voltage is specified. The display device is provided on the panel surface of the power supply unit configured for each output voltage so that the power supply unit to be replaced can be specified.

  In general, the power supply apparatus is provided with an external power supply output off circuit. When the output is off, the voltage monitoring circuit performs a failure notification and masks the display device in order to detect a voltage drop despite no failure.

In addition, as a well-known document relevant to this application, there exist the following, for example.
JP-A-4-172539

  However, in order to mask the failure notification and the display device, it is necessary to transmit a mask signal for each power supply unit, and it is necessary to provide a mask circuit for each power supply unit. For this reason, there is a problem that the number of parts increases and the apparatus becomes complicated and large.

  The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide a power supply failure display device that can accurately notify a power supply failure with a simple configuration.

  In order to achieve the above object, a power failure display apparatus according to the present invention includes a voltage monitoring circuit that monitors whether or not an output voltage of a power supply module is normal, the voltage monitoring circuit connected to the voltage monitoring circuit, When the normality is detected, the current supply terminal is short-circuited, and when the voltage monitoring circuit detects an abnormality, the current supply terminal is opened, and the switch means is connected to both ends of the switch means. A light-emitting element that emits light in an open state, a notification unit that is connected to the switch unit and notifies a power supply abnormality to the outside when the current supply terminal is in an open state, and a mask signal that instructs to turn off the power supply module And a mask means for releasing the open state of the current supply end.

  According to the power failure display device having the above-described configuration, when the voltage monitoring circuit detects normality, no current flows through the light emitting element and the notification unit. Therefore, the light emitting element is turned off and no failure notification is performed by the notification unit. On the other hand, when the voltage monitoring circuit detects an abnormality, a current flows through the light emitting element and the notification unit, so the light emitting element emits light, and the notification unit notifies the power supply abnormality. Further, the open state of the current supply end is canceled according to the mask signal, so that no current flows through the light emitting element and the notification means. With this configuration, it is possible to display a failure, notify a failure, and mask an abnormality with fewer parts.

  Therefore, according to the present invention, it is possible to provide a power failure display device that can accurately notify a power failure with a simple configuration.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a circuit diagram showing a configuration of a power failure display device according to an embodiment of the present invention.
The power failure display device includes a voltage monitoring circuit 1, a photocoupler 2, an LED (Light Emitting Diode) 3, a resistor 4, a digital transistor 5, a transistor 6, and a DC / DC converter 7. The DC / DC converter 7, the voltage monitoring circuit 1, the photocoupler 2, and the LED 3 are arranged in the power supply unit.

  In the figure, a DC / DC converter 7 is connected to a digital transistor 5 via a voltage monitoring circuit 1 and a photocoupler 2. The voltage monitoring circuit 1 detects an abnormality such as an overvoltage or a voltage drop based on the output voltage of the DC / DC converter 7. The resistor 4 supplies a current for operating the photocoupler 2. The LED 3 is connected to both ends of the photocoupler 2, and when the photocoupler 2 is open, current is supplied from the resistor 4 to display an abnormality. The transistor 6 is an output of a mask signal instructing to turn off the power and is disposed other than the power unit. The transistor 6 is commonly connected to the photocoupler 2, the LED 3, and the digital transistor 5.

The operation of the power failure display device configured as described above will be described.
First, when the voltage monitoring circuit 1 detects normality, the output of the photocoupler 2 is short-circuited and the current from the resistor 4 flows to the photocoupler 2. For this reason, the LED 3 is turned off (normal). Further, the digital transistor 5 is also turned off to notify normality.

  When the voltage monitoring circuit 1 detects an abnormality, the output of the photocoupler 2 is opened and the current from the resistor 4 flows to the LED 3 to display the abnormality. Furthermore, a current flows through the digital transistor 5 and turns on to notify the outside of the abnormality.

  When a mask signal for instructing power off is supplied, the transistor 6 is turned on, so that the current from the resistor 4 flows to the transistor 6 even when the output of the photocoupler 2 is open. By this operation, no current flows through the LED 3 and the LED 3 is turned off (normal). Further, the digital transistor 5 is also turned off to notify normality.

  As described above, according to the above-described embodiment, when the voltage monitoring circuit 1 detects normality, no current flows through the LED 3 and the digital transistor 5, so the LED 3 is turned off, and the failure notification by the digital transistor 5 is performed. Absent. On the other hand, when the voltage monitoring circuit 1 detects an abnormality, a current flows through the LED 3 and the digital transistor 5, so that the LED 3 emits light and the digital transistor 5 notifies the power supply abnormality to the outside. Further, when the transistor 6 is turned on according to the mask signal, normality is notified because no current flows through the LED 3 and the digital transistor 5 even if the output of the photocoupler 2 is open. With this configuration, it is possible to display a failure, notify a failure, and mask an abnormality with fewer parts.

  Therefore, according to the above embodiment, it is possible to provide a power failure display device that can accurately notify a power failure with a simple configuration.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

The circuit diagram which shows the structure of the power failure display apparatus which concerns on one Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Voltage monitoring circuit, 2 ... Photocoupler, 3 ... LED, 4 ... Resistor, 5 ... Digital transistor, 6 ... Transistor, 7 ... DC / DC converter.

Claims (2)

A voltage monitoring circuit for monitoring whether or not the output voltage of the power supply module is normal;
Switch means connected to the voltage monitoring circuit, short-circuiting the current supply terminal when the voltage monitoring circuit detects normality, and opening the current supply terminal when the voltage monitoring circuit detects abnormality;
A light emitting element connected to both ends of the switch means and emitting light when the current supply end is in an open state;
A notification means connected to the switch means for notifying a power supply abnormality to the outside when the current supply terminal is in an open state;
A power failure display device, comprising: mask means for releasing the open state of the current supply end based on a mask signal instructing power off of the power supply module.   2. The power failure display device according to claim 1, wherein the switch means is a photocoupler.

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