JPS5857799B2 - Alarm detection circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to sense when a detection circuit of an automation device, security device, etc. is accidentally or intentionally disconnected or short-circuited.

In particular, many conventional crime prevention devices do not operate if the edge is cut, and those that operate if the edge is cut only fail if the detection wire is short-circuited.

The present invention was developed to be able to operate in any of these cases, and this invention makes it difficult to distinguish the wires by stretching twisted conductor wires in the detection circuit. Even if an attempt is made to stop the device from operating due to a short circuit, a warning will be issued, and this device can be used not only as a crime prevention device but also for a wide variety of purposes such as detecting short circuits and disconnections.

The invention will be explained with reference to the embodiments shown in the accompanying drawings.

FIG. 1 explains one embodiment of the present invention. When the first stage transistor 1 of the switching amplification circuit (alarm device) on the right side of the outlet C is turned on, the other transistors 2 and 3 are turned on, and the relay 4 is turned on. operates, contact 5 closes, and buzzer 6 sounds.

In the switching amplifier circuit described above, a relatively high resistance is used as the gate resistor 7 of the first stage transistor 1, and the current is limited and connected to the shunt circuit 8, and the transistor 1 is turned off by shunting the current in the direction of the arrow in the figure. Adjust the resistance 9 to maintain the condition.

Therefore, when the break contact 10 is turned off, the shunt current stops and the transistor 1 is turned on to issue an alarm.

Further, an electrically insulated conductor 1 is provided along with the shunt circuit 8.
A resistor 12, which is relatively lower than the resistor 7, is connected to the terminal 1.11' to provide a sub-circuit with an open end in parallel with the shunt circuit 8.

If the conductor wires 11, 11'(11' is an extra addition) of the sub-circuit are insulated wires that are twisted together with the branch circuit 8 and are indistinguishable, cutting the wires will disconnect the distribution circuit 8. Therefore, the transistor 1 is turned on, and if the insulated wire 11.11' is short-circuited to the shunt circuit 8, the conductor wire 11.11' is short-circuited to the shunt circuit 8, and the resistance 7°12
A parallel circuit is formed, and the pace current 13 of transistor 1 increases, turning on transistor 1, which also generates an alarm.

In other words, even if these lines are cut or shorted, the transistor will operate and issue an alarm.

FIG. 2 shows an embodiment in which a circuit of a conductive wire 11 including a photosensitive element 14 such as a CDS is placed along a shunt circuit 8. When the CD 514 is not exposed to light, the resistance of the CD 514 is large and the transistor 1 is turned off. Current flows through the maintenance shunt circuit 8 in the direction of the arrow.

When light hits the CD 514, its resistance value decreases and current flows, transistor 1 is turned on and an alarm is issued.

An alarm is also issued if wires 11 and 8 are connected in the middle.

If the current is cut off at the position indicated by the two-dot chain line 15 in the figure, the current in the shunt circuit 8 will be cut off, the transistor 1 will be turned on, and an alarm will be issued in the same way.

A thermistor, bimetal or other variable impedance element or switching element can also be used in place of the CDS.

In addition to the above, by inserting a CDS in place of the break contact 10 shown in FIG. 1, it is possible to construct a circuit in which the alarm does not sound while the light is shining on it, but which sounds the alarm when the light is completely interrupted.

A plurality of contacts 10 can be provided in series or in parallel.

Further, by utilizing the contacts 10, the high-resistance photoelectric element 14, the third conductive wire, etc., it is also possible to construct circuits for various ground failures, disconnection failures, etc.

Although the above embodiments have been explained using NPNI-transistors, the present invention can be similarly applied to PNP-1-transistors, and the circuit configuration may be different from the power source when connecting a shunt circuit. It can be freely modified within the scope of the present invention, such as by connecting it to the other side using the same principle.

In addition to the above, the target object can be freely changed according to various purposes such as controlling a motor or a floodlight instead of an alarm, and the above-mentioned features of the present invention allow it to be used widely and effectively.

[Brief explanation of drawings]

1 and 2 are circuit diagrams of embodiments of the present invention, respectively. 1.2,3...transistor, 4...
Relay 5... Relay contact, 6... Buzzer, 7... J... Gate resistor, 8... Shunt circuit, 10... Break contact, 11.11'...
...Conducting wire, 14...Photosensitive element.

Claims (1)

[Scope of Claims] 1. A shunt circuit is provided in the switching control input circuit of a switching amplification circuit using switching elements such as transistors and ICs, and the input current is shunted at an appropriate ratio through this shunt circuit. is set in the off (or on) state, and the switching amplification circuit is configured to operate on (or off) when this shunt circuit is disconnected, and another conducting wire is insulated along the shunt circuit. and one end of the conductive wire is connected to the power source of the switching control input circuit, and when this conductor is short-circuited to the shunt circuit, it forms a short circuit for a part of the switching control input circuit and turns on the switching amplification circuit. An alarm detection circuit characterized by being activated (or off). 2. The alarm detection circuit according to claim 1, wherein one end of an insulated conductive wire is connected to a power source, the other end is open, and the conductive wire is run along a shunt circuit. 3 Connect one end of the conductor wire that ran along the shunt circuit to the power supply,
2. The alarm detection circuit according to claim 1, wherein the other end is connected to a shunt circuit via a variable impedance element such as a thermistor or a photoelectric element. 4. The alarm detection circuit according to claim 1, wherein one end of the conductive wire running along the shunt circuit is connected to a power source, and the other end is connected to the shunt circuit via a switching element.