JPS62154521A - Fuse discontinuity alarm circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fuse, and more particularly to a storage circuit having an audible and visual means when the fuse is blown. Most of the time, for communications equipment and other devices that are heavily influenced by fuses, the fuse blown alarm system has been used to issue a visible and audible alarm when the fuse blows. Figure 5 shows an example of a conventional fuse with a fuse, in which 1 is a fusible piece, 2
．． 3 is the main electrode.

4 is the leaf spring, 5 is the alarm display section, and 6.7 is L! 5 Alarm electrode, 8 a protrusion, 9 a contact, 10 an insulator that supports the entire fuse structure, 11 an insulator that supports the alarm electrodes 6 and 7, 12 a fuse force sensor, 13 a window It is.

In this example, the leaf spring 4 is pulled by the fuse wire 1, and when the door cover 12 is attached, the alarm display part 5, which is a part of the leaf spring 4, is shifted from the position of the window 13 and cannot be seen. It looks like this. Moreover, the circuit between the alarm electrodes 6 and 7 is open. Now, when this Hiez is in use, if some abnormality occurs in the equipment and the fusible piece breaks,
The leaf spring 4 returns to its elasticity and pushes the protrusion 8 of the alarm electrode 6, which pushes the electrode 6 and closes the contact 9 of the electrode 7.
When the electrodes 6 and 7 come into contact with each other, a short circuit occurs between the electrodes 6 and 7. At the same time, window 13
The bulletin display section 5 (usually painted white) is located just below the window 13, and the window 13 appears white.

Electrodes 6 and 7 are connected to the bell circuit, so when the fuse itself and the bell circuit break, an audible (bell) and visible (alarm display on window 13) alarm will be generated, and the maintenance personnel will be able to restore the system immediately. Measures can now be taken.

Problems to be Solved by the Invention As mentioned above, the example shown in Fig. 1 is very cleverly constructed, but compared to the 4-I4I electronic devices, which have recently become increasingly smaller and more MW-packed, However, there is a tendency for it to become large. Although efforts are being made to make the alarm function (=j) smaller as shown in this example, there is a limit to the miniaturization of fuses with mechanically movable parts, and it is important to keep the size below a certain level. The disadvantage was that it was difficult.

Means for Solving the Problems In order to eliminate the above-mentioned drawbacks, the fuse blowout alarm circuit of the present invention detects that the voltage applied through the fuse disappears when the fuse blows. The purpose of this invention is to have a means for collecting and processing this and generating a visible and audible alarm, thereby reducing the size of a fuse with an alarm function, and simplifying and increasing the efficiency of maintenance. In short, it generates an alarm by detecting the disappearance of the voltage applied to the equipment due to a blown fuse, eliminating the need to provide a special alarm function at the fuse location.

Figure 1 shows this principle. If the voltage applied to the NAND circuit is led through the fuses, no output will appear in the NAND circuit when all the fuses are normal, but if one of the fuses is blown. When this happens, one of the inputs of the NAND circuit becomes low. Therefore, an output appears in the NAND circuit. Therefore, visual and audible alarms can be created by processing this output. For example, the display device can display the device name and the device number, and it is also possible to transfer this information to another location.

Embodiment FIGS. 2 and 3 show an embodiment of the fuse alarm circuit according to the present invention.

In FIG. 2, ioo is the unit of the monitored device, 11
1,112. =-11n is a fusible piece of fuse, 121,
122. ...12n is a light emitting diode.

131.132. =43n is a light emitting diode 121°1
22, -・-1211 current limiting resistor, 151°15
2.---15n is a capacitor, 141,142°...
・14n is a circuit to be monitored which is independent within the unit and unit, and is, for example, a glint board. 1
61,162. ...16n is a reverse current blocking diode, 170 is a gate current limiting resistor of thyristor 180,
190 is an anode tR of the thyristor 18o, a limiting resistor, and 240 is a repelling electric key.

210 is a light emitting diode for indicating that a -z disconnection has occurred in unit, t, and 2; 22o is a light emitting diode 2;
1 of 10 is a resistor for optical limiting, 23o is a reverse current blocking diode, -vee is a negative neutrality power input terminal, ALM OUT
is the alarm output terminal from unit and to.

Next, Fig. 3 shows the implementation row of the centralized death alarm unit, and in the figure 300 is the alarm unit, 311, 312°...
is a light emitting diode, ■LL is a relay, rl is a contact point of the relay, A LM I Nl'! Figure 1 ALMOU
T is the blueprint input terminal that can accept multiple inputs, and BELJji is the output terminal to the bell circuit.

The operation of Figure 2 will be explained. light emitting diode 1
21,122. . . 12n is for notifying the position of the fuse that has become a fusible piece, and is originally short-circuited by a fusible piece and does not emit light, but when the fusible piece is broken, the circuits 141, 142... . . . Since a reverse current flowing through i4n should flow, this is used to light up the light emitting diode, thereby increasing the position of the blown fuse. The resistors 131, 132, . . . -13n limit the current flowing through the light emitting diodes 121, 122, . ... Since the DC resistances of 14n are not equal, the brightness of the diode is adjusted using these resistances. The above-mentioned light emitting diode and resistor may be built into the interior of the fuse case or may be provided independently of the fuse, or may not be provided as long as the fusible fragments are easily visible. In other words, it is a function with a wide range of freedom of choice.

Capacitors 151, 152. -15n is intended to detect only the voltage rise in the positive direction when the fusible piece breaks.
The purpose of this is to first send out a message of great news,
To enable the maintenance personnel to turn off the alarm and issue the qi alarm again if another fuse becomes defective until the defective fuse is restored.]2. j.

The standby is for providing a function, and if the function is not particularly required for the standby during IEI production after the fuse, these capacitors are unnecessary and can be made DC conductive. The diodes 161, 162°...16n are the first
One circuit 141, 142 in the NAND circuit in the figure
．． When a positive voltage (if there is a capacitor 151, 152, . . . 15n) or a positive voltage (if there is no capacitor) is applied to any of the -14n and 75 planes, the tri-force supplies current to the gate of the thyristor 18o, This turns on the thyristor. A light emitting diode 210 is placed on the front of the unit, etc., and lights up when the thyristor 180 is turned on, providing a visible alarm that a 1-spring failure has occurred in this unit. Bounce! key 24
0 is for turning off the alarm, and if the above-mentioned standby function is provided, pressing this trap will cause the current in the thyristor to drop, so the thyristor will be turned off. If the fusible piece of the other fuse is then blown, that voltage pulse can again issue an alarm.

Furthermore, the anode circuit of the thyristor is connected from the ALM OUT to the Al, M 1 NIC of the alarm unit 300 in FIG. 3 through the backflow blocking diode 230. AL
MIN is light emitting diode 311°3cm2. ...31r
A positive voltage is applied through n and relay RL. Therefore, when thyristor 180 in FIG. 2 is tripped and turned on, current flows from ground to relay RL to light emitting diode (for example, 311) to diode 230 in FIG. 2 to thyristor 180 to resistor 190 to -Vcc. Therefore, the relay is operated to issue an audible alarm such as a bell, and the light emitting diode corresponding to the monitored unit 100 lights up in the alarm unit 300, thereby making it a town celebration.

The diode 230 in FIG.
This is to prevent the current from 10 from flowing back into the alarm unit 30°.For example, if the current from the monitored unit 10
Something other than 0 operates as an alternate alarm, and the third cause is light emitting diode 3.
Assuming that 1rn lights up, the light emitting diode 230 will pass through the light emitting diode 230. Since diodes generally have low reverse voltage resistance, the current from the light emitting diode 210 will connect the light emitting diode 311 in the reverse direction. , there is a risk that it may cross over to the light emitting diode 31m. The diode 230 is intended to prevent such inconveniences.As can be seen from the above description, according to the present invention, when the fusible piece of the fuse in the existing unit is disconnected, the concentration f\i1 is first An audible alarm is generated. Further, in the alarm unit, a light emitting diode indicating the position of the faulty unit lights up, and a light emitting diode for alarm also lights up in the faulty unit. Here, the standby function can be freely selected, and then the alarm must be temporarily stopped by operating the t key, and the defective fuse must be replaced. However, at this time, the alarm display light emitting diodes of the individual fuses can be optionally turned on, and if any of them are lit, the defective fuse can be immediately identified.

FIG. 4 is a diagram showing a concept of another embodiment of the central alarm unit, 400 is an M alarm unit, 400. In the figure, ALM
It is assumed that the fuse blown information from the valley panel is input at the INj alarm input terminal in negative logic. 411,4
12. -41m is an AND circuit, 430 is a ring counter, and the clock of the clock generator 460 is
The d path 470 is received through the AND circuits 411, 412 .
Apply scanning pulses to -41m. And ALMIN
goes low and the output of the AND circuit (eg 411) goes high only when the K scan pulse is supplied. 42
0 is an OR circuit, and AND circuits 411, 412, .
...If any of 41m becomes high, its output becomes high. This output causes the F)AND circuit 470 to stop the clock output, and thus also stop the ring counter, ie, the scan pulse. That is, the scanning pulse is generated by the AND circuit 411.
It will stop outputting output. 440 is a display circuit.

Upon receiving the counting information of the stopped ring counter, -T: is converted into appropriate information@VC and displayed.

The display should only appear in the event of a failure. In the diagram, glue 1
252 lines 30. Shelf 918. An example of unit 647 is shown. The housing 450 is an interface that is used to transfer this alarm information as series data to other locations.

The logic circuit described above uses a microcomputer, memory, etc., and can be used not only for software control but also for software control.
Of course, this method can be used in conjunction with processing not only heat alarms but also other alarms, thereby making the alarm unit highly efficient and economical.

Effects of the Invention As explained above, according to the present invention, it is possible to monitor a large number of compact and densely packed fuses, which greatly contributes to improving the efficiency of equipment maintenance. is.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the principle of the present invention, Fig. 2 is an embodiment of a fuse reporting circuit according to the present invention, Fig. 3 is an embodiment of a centralized alarm unit, and Fig. 4 is a diagram showing another example of a centralized interphase unit. FIG. 5 is a perspective view showing an example of a conventional fuse with an alarm. 100...Monitored device unit, 111, 11
2゜...lln... Fusible piece of fuse, 12
1,122°...12n...Light-emitting diode, 131,132°...13n...Resistor, 1
41,142. ...14n...Monitored circuit, 1
51,152. ...15n... Capacitor,
161,162. ...16n...Diode, 170,190,220...Resistance, 180.
... Thyristor, 210 ... Light emitting diode, 230 ... Diode, 240 ...
A bouncy electric key. -V CC...- Negative polarity power input terminal, ALM O
UT...Alarm output terminal. ...-Vζ- Agent Patent Attorney Chestnut 1) Spring, S: Hanging 5°, He

Claims (3)

[Claims] (1) In an electronic device to which power supply voltage is supplied from the power supply via a built-in fuse, when the fuse is blown, it is detected that the power supply voltage is no longer being properly supplied to the electronic device. What is claimed is: 1. A blown fuse alarm circuit comprising: a circuit for detecting a blown fuse; and an alarm circuit for issuing a blown fuse alarm based on an output signal from the detection circuit. (2) The fuse blowout alarm circuit according to claim 1, further comprising a light emitting diode connected in parallel to the fuse to indicate a fuse blowout. (3) A plurality of series circuits each including a fuse and an electronic device are connected in parallel between the power supply and the ground, and the voltage at each connection point between the fuse and the electronic device is input to a common NAND circuit; 2. The fuse blowout alarm circuit according to claim 1, wherein the output signal of the NAND circuit forms a drive signal for the alarm circuit.