JPH0457194A - Output circuit for fire sensor - Google Patents

Abstract

PURPOSE:To obtain a circuit capable of performing a normal operation even when a source voltage is highly fluctuated by providing a three-terminal regulator between a receiver and a relay coil connected to a sensor. CONSTITUTION:A voltage applied to the relay coil 4 can be stabilized by the three-terminal regulator 6 by connecting the three-terminal regulator 6 between the receiver 1 and the relay coil 4 connected to a fire sensor 2 even when the source voltage is highly fluctuated. Therefore, it is possible to always perform a stable operation without limiting a relay to be used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an output circuit for a fire detector that outputs an alarm from a sensor through a relay contact.

[Prior Art] Figure 3 shows a conventional output circuit for this type of fire detector.
A detector 2 for detecting fire is connected by a line 3 from a receiver 1, and one line 3 is connected with a relay winding 4, a light emitting diode LED, etc. and,
Power is supplied from the receiver 1 to the line 3.

In a warning state in which the detector 2 does not detect a fire, both lines 3 are open in the detector 2, no current flows through the relay winding 4, and the light emitting diode LED is also turned off. Sensor 2
When a fire is detected and both lines 3 are short-circuited (alarm is issued), a current exceeding the current of the relay flows through the relay winding 4, and the relay winding 4 is energized to output the contact 5 output. .

[Problems to be Solved by the Invention] In this conventional example, the power to the relay winding 4 is supplied from the receiver 1, but - for boat fishing, the power supply voltage fluctuates considerably (about 15 to 30 V). ), the voltage applied to the relay winding 4 fluctuates greatly when the sensor 2 issues an alarm, resulting in the problem that the types of relays that can be used are extremely limited.

The present invention has been provided in view of the above points, and 2.
It is an object of the present invention to provide an output circuit for a fire detector in which a relay can operate normally even if there is a large fluctuation in power supply voltage, and the type of relay is not limited.

[Means for Solving the Problems] The present invention connects a relay winding to a line connected between a receiver to which power is supplied and a fire detector, and detects the above-mentioned problems by the operation of the detector. This is an output circuit for a fire detector that excites a relay winding and outputs a relay contact output, in which a three-terminal regulator is provided between the receiver and the relay winding.

Further, a switching element that is turned on by the operational output of the sensor is provided between the receiver and the three-terminal regulator.

[Function] Thus, the three-terminal regulator prevents fluctuations in the power supply voltage applied to the relay winding.

Further, in claim 2, the switching element is turned on by the operational output of the sensor to apply power to the three-terminal regulator, thereby preventing fluctuations in the power supply voltage applied to the relay winding by the three-terminal regulator, and When the sensor is in a warning state, the switching element is turned off to minimize current consumption during the warning state.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
As shown in the figure, a three-terminal regulator 6 is inserted and connected between a receiver 1 and a relay winding 4 in a conventional circuit. Therefore, even if the power supply voltage supplied from the receiver 1 fluctuates greatly, the voltage applied to the relay winding 4 will be stabilized by the three-terminal regulator 6. Therefore, the relays used are not limited either. In addition, the operation is the third
Same as in the figure.

However, in this embodiment, as indicated by the arrow shown in FIG. 1, a leakage current flows through the three-terminal regulator 6 in the alert state, so there is a problem that the consumption type current in the alert state increases.

Therefore, the embodiment shown in FIG. 2 is an improvement on FIG. 1. In other words, transistor Q1.3 is placed on one line 3 side.
Connect the terminal regulator 6, relay winding 4, etc., and
Resistors R, , R2, which drive the transistor Q, are connected to the other line 3 side.

When the sensor 2 detects a fire, the value of the current Is increases, the potential difference between the base and emitter of the transistor Q increases, and the transistor Q turns on. Then a
An electromotive force close to the power supply voltage ■ is generated at the point, and a sufficient voltage is applied to the relay winding 4 via the three-terminal regulator 6.
Relay works. With this configuration, even if the power supply voltage V fluctuates greatly, the voltage applied to the relay winding 4 is almost constant, so a large number of types of relays can be used.
Moreover, during alarm, the transistor Q1 is off, so the current consumption is extremely small.Also, even if the sensor 2 generates an alarm, the current flowing through the relay winding 4 does not flow into the sensor 2, so it is not detected. The withstand current of the device 2 can also be small.

The experimental data for the case of Fig. 2 when the sensor is alerted and when an alarm is issued is shown below.

(When the sensor is alert) (When the sensor is activated) Note that the resistance R is 100Ω, and the resistance R2 is 1Ω.

[Effects of the Invention] As described above, the present invention connects a relay winding to a line connected between a receiver to which power is supplied and a fire detector, and the above-mentioned effect is achieved by the operation of the detector. In a fire detector output circuit that excites the relay winding and outputs a relay contact output, a three-terminal regulator is installed between the receiver and the relay winding, so the power supply voltage is controlled by the three-terminal regulator. Even if the fluctuation in the power supply voltage is large, fluctuations in the power supply voltage applied to the relay winding can be prevented, and this has the effect of increasing the number of types of relays that can be used.

Furthermore, since a switching element is provided between the receiver and the 3-terminal regulator that is turned on by the operating output of the sensor, the switching element is turned on by the operating output of the sensor and the 3-terminal regulator is turned on by the operating output of the sensor. Apply power to the regulator,
A three-terminal regulator can prevent fluctuations in the power supply voltage applied to the relay winding, increasing the number of types of relays that can be used.However, when the sensor is in an alert state, the switching element is Since it is turned off, the current consumption during the warning period can be extremely reduced.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, FIG. 2 is a circuit diagram of another embodiment same as the above, and FIG. 3 is a circuit diagram of a conventional example. 1 is the receiver, 2 is the sensor, 3 is the line, 4 is the relay winding,
5 is a relay contact, 6 is a three-terminal regulator, and Q is a transistor. Agent Patent Attorney Ishi 1) Choshichi

Claims (2)

[Claims] (1) A relay winding is connected to the line connected between the receiver to which power is supplied and the fire detector, and the relay winding is energized by the operation of the detector, and the relay contacts are activated. 1. An output circuit for a fire detector which outputs an output, characterized in that a three-terminal regulator is provided between a receiver and a relay winding. (2) The output circuit for a fire detector according to claim 1, further comprising a switching element which is turned on by the operational output of the detector and is provided between the receiver and the three-terminal regulator.