JPS6319916Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a gas alarm system that is composed of a gas leak alarm, an outdoor alarm, a central monitoring panel, etc., and that is connected by a voltage signal. This invention relates to an inspection device that prevents external alarms (buzzers), central monitoring panels, etc. from malfunctioning when inspecting inspection gas.

Generally, when inspecting a gas leak alarm, a method is used to spray inspection gas directly onto the gas sensor and set off an alarm buzzer.However, in the case of a gas alarm system, an external In accordance with this inspection, alarms, central monitoring panels, etc. will behave in the same way as an alarm in the event of a gas leak. Therefore, at the time of this inspection, it is sufficient that the entire system does not operate, but only the gas leak alarm device being inspected as a terminal device issues a gas leak alarm operation.

In view of this, the present invention aims to provide an inspection device in which only the gas leak alarm is activated during inspection, and does not affect the others (does not issue false gas leak alarm signals). be.

Hereinafter, preferred embodiments of the present invention will be described in detail as illustrated in the accompanying drawings.

FIG. 1 shows a gas alarm system to which the inspection device according to the present invention is applied. Gas leak alarm 2
has a voltage output terminal 4. The voltage output terminal is connected to, for example, an outdoor alarm 6 such as a buzzer that does not have its own power source, or a gas leak central monitoring board 8 that can have its own power source. As shown in FIG. 2, the voltage signal changes to three levels (0V, 6V, 12V) according to four cases.

That is, in the first case, the power plug 10 of the gas leak alarm 2 is intentionally or inadvertently disconnected, and the voltage signal at this time is 0V. Therefore, the buzzer of the outdoor alarm 6 and its power lamp are turned off, and the central monitoring board 8 shows 0V and the impedance R of the voltage output terminal 4 as seen from the outside.
is detected and, for example, the corresponding first fault lamp is turned on.

In the second case, a disconnection occurs in the signal line 12 to which the gas leak alarm 2 is connected, and the voltage signal at this time is also 0V. Therefore, the outdoor alarm 6 behaves the same as in the first case, but the central monitoring board 8 receives the voltage signals 0V and R due to the disconnection of the signal line 12.
detects infinite impedance and turns on the corresponding second fault lamp, for example.

The third case is a so-called standby state in which the entire system is functioning normally, and the voltage signal at this time is 6V. In this case, the outdoor alarm 6
Only the power lamp is lit, and only the power lamp of the central monitoring board 8 is lit.

In the fourth case, a gas leak alarm occurs, and the voltage signal is 12V. In this case, the outdoor alarm 6
, its power lamp and buzzer are turned on, and the central monitoring panel 8 turns on the indicator lamp of the location corresponding to the alarm 2 that detected the gas leak, and also turns on the buzzer.

FIG. 3 shows an example of a device that is built into the gas leak alarm 2 and generates the above-mentioned voltage signal.

The voltage signal generator includes a general rectifying and smoothing circuit connected to a power transformer (only the secondary side is shown), a circuit consisting of a control transistor 14 and two Zener diodes 16 and 18, and a resistor R. There is. The two Zener diodes each have a voltage of 6 V, for example, and one of them is connected in parallel to a contact 20 of a relay provided on the gas leak detection part side. In the third case, this contact point 20 is
In other words, it is short-circuited in the standby state. Furthermore, a normally open switch 22 is connected in parallel with this relay contact 20. This switch 22 is a switch that is closed in conjunction with the inspection gas container being pressed against the inspection port to check the operation of the gas leak alarm 2.

FIG. 4 is a diagram showing an example of how the switch 22 is attached. Contact points 24 and 26 of the switch 22 are embedded in a recessed side wall of an inspection port 28 of the gas leak alarm. In this figure, the inspection gas container is inserted into the inspection port 28 from the left toward the gas sensor 30 inside the alarm.
the contacts 24, 2 of the switch 22.
6 closes, shorting the Zener diode 18 of FIG. As a result, even if the gas sensor 30 is sprayed with inspection gas and the gas leak alarm 2 is set to the alarm state in the fourth case, and the relay contact 20 is opened, the Zener diode 18 is still short-circuited. Therefore, the voltage signal generator outputs a 6V signal in the standby state. As a result, the external alarm device 6 and the central monitoring panel 8 behave in the same manner as in the standby state.

According to a preferred embodiment, a timer is activated at the same time as the inspection gas container is removed, and the switch 2 is activated for a predetermined period of time.
2 can also be left closed. This is to prevent the alarm from erroneously reporting the residual gas, since the inspection gas near the gas sensor 30 will not disappear the moment the inspection gas container is removed from the inspection port.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a gas alarm system to which the device of the present invention is applied, Figure 2 is a diagram showing an example of a voltage signal generator, Figure 3 is a diagram showing an example of a voltage signal generator, and Figure 4 is a diagram showing an example of a voltage signal generator. FIG. 3 is an enlarged cross-sectional view showing the vicinity of the inspection port. 2... Gas leak alarm, 4... Voltage output terminal, 6... Alarm, 8... Central monitoring panel, 10...
Plug, 12... Signal line, 14... Transistor, 16, 18... Zener diode, 20...
...Relay contact, 22...Switch, 24, 26...
...Contact, 28...Inspection port, 30...Gas sensor.

Claims (1)

[Scope of utility model registration request] It consists of a gas leak alarm, an alarm installed at a remote location, a central monitoring panel, etc., and the gas leak alarm is equipped with a voltage signal that expresses various status information by changes in voltage level. In a gas alarm system that includes a device that generates a gas leak alarm, and is capable of identifying the state of a gas leak alarm according to the level of a voltage signal in the alarm, central monitoring panel, etc., the gas sensor of the gas leak alarm When spraying inspection gas into the gas tank, a switch is operated in conjunction with the pressing of the inspection gas container against the inspection port, and the contact signal of this switch causes the voltage signal to change to a signal corresponding to the gas leak alarm state. An inspection device for a gas alarm system, characterized in that it does not switch.