JPS5816071Y2 - Kasaikantiki - Google Patents

Description

[Detailed description of the invention] The present invention connects a thyristor 3 on the sensor side in parallel to a series circuit of a DC power supply 1 and a load 2 such as a relay provided on the receiver R side, and Applying power to the sensing circuit section from both ends of the thyristor 3, and forming a charge storage circuit 4 in parallel with the thyristor 3 in the sensing circuit section,
In the fire detector in which the thyristor 3 is triggered by the output of the sensing circuit section, the charge accumulation circuit 4 includes a bypass circuit 13 that allows a current higher than the holding current to flow from the charge accumulation circuit 4 to the anode of the thyristor 3 when the thyristor 3 is operated. The present invention relates to a fire detector which is inserted and connected between the positive terminal of the thyristor 3 and the anode of the thyristor 3, and its purpose is to provide a fire detector which can reliably perform the fire detection operation of the detector.

FIG. 3 shows a conventional example circuit, in which the light emitting diode 8 is decremented by the output of the oscillator circuit 7, the light is received by the light receiving element 9, the output is amplified by the amplifier circuit 10, and the output from the light emitting diode 8 is transmitted to the light receiving element. 9, a sensing circuit section is configured such that the trigger element 5 is made conductive by the output of the amplifier circuit 10 generated when the O incident light is blocked by smoke, etc., and this sensing circuit section receives a constant voltage from both ends of the thyristor 3. Power is supplied through the circuit 11, and a charge storage circuit 4 such as a capacitor is connected in parallel between the power supply terminals of the oscillation circuit 7 and the amplifier circuit 10.

However, in the above circuit, when the light incident on the light receiving element 9 is blocked by smoke or the like, an output is generated in the amplifier circuit 10, and N
When the output pulse of the amplifier circuit 10 is applied to the gate of the trigger element 5 consisting of a gate thyristor, conduction occurs between the anode and cathode of the trigger element 5, and the gate current of the thyristor 3 is applied from the constant voltage circuit 11, and this thyristor 3 becomes conductive, and a load 2 such as a relay provided on the receiver R side is driven.

However, in the conventional circuit as described above, even if a gate current is applied from the trigger element 5 to the gate of the thyristor 3 when a fire is detected, the current 11 flowing into the anode of the thyristor 3 is caused by the load 2 as shown in FIG. If there is a delay as shown in , and the gate current disappears before the anode current 1 reaches the holding current value of the thyristor 3, the thyristor 3
There was a drawback that the system did not operate and no fire detection operation was performed.

The present invention has been proposed in view of the above-mentioned points, and the present invention will be described below with reference to embodiment figures.

FIG. 1 shows an embodiment of the present invention, in which there is a
A bypass circuit 13 is inserted and connected so that the anode direction of the thyristor 3 is the forward direction.

This bypass circuit 13 supplies a current I2 higher than the holding current from the charge storage circuit 4 to the anode of the thyristor 3 when a fire is detected. Therefore, when a gate current flows into the gate of the thyristor 3 in the circuit of this embodiment, the thyristor Anode current flowing to the anode of 3 ■ 3 is the second
As shown in the figure, a current that is the sum of the current ■1 flowing from the receiver R side and the current ■2 flowing through the bypass circuit 13 flows into the anode of the thyristor 3, and a current higher than the holding current flows into the anode of the thyristor 3. This will ensure that it is turned on.

12 is a recovery switch. As mentioned above, the present invention has a bypass circuit that allows a current higher than the holding current to flow from the charge storage circuit to the anode of the thyristor during operation of the thyristor, so that the current flowing from the receiver side to the anode of the thyristor reaches the holding current of the thyristor. Even if the thyristor's gate current disappears beforehand, the bypass circuit supplies the thyristor's anode with a current greater than the holding current, ensuring that the thyristor conducts and provides a highly reliable fire detector without malfunctions. It is something.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram of the present invention-embodiment, Figure 2 is a comparison diagram of the current value flowing into the anode of the same thyristor, Figure 3 is a circuit diagram of a conventional example of the present invention, and Figure 4 is a conventional example. 1 is a diagram showing the current value flowing into the anode of the thyristor, 1 is a DC power supply, 2 is a load, 3 is a cynostar, 4 is a charge storage circuit,
13 is a bypass circuit, K is a sensor, and R is a receiver.

Claims (1)

[Scope of utility model registration request] A thyristor on the sensor side is connected in parallel to a series circuit of a DC power supply and a load such as a relay provided on the receiver side, and power is supplied to the sensing circuit section in the sensor from both ends of the thyristor, and the inside of this sensing circuit section is In the fire detector described above, which has a charge storage circuit connected in parallel with the thyristor, and the thyristor is triggered by the output of the sensing circuit, when the thyristor is operated, a holding current is applied to the anode of the thyristor from the charge storage circuit. A fire detector consisting of a bypass circuit that allows the flow of a current greater than or equal to the amount specified above and is inserted and connected between the positive terminal of the charge storage circuit and the anode of the thyristor.