JPS6234397Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Application) The present invention relates to a fire detector having a constant voltage element that protects internal components.

(Problems with the Prior Art) In general, this type of fire detector, as shown in Figure 2, has a series circuit between the fire relay of the fire receiver (A) and the DC power supply (C), which is switched in response to a fire phenomenon in the fire detector (2). A series circuit between an operating detection circuit E and an operation display circuit of this detection circuit E is connected in parallel, and a constant voltage element G is connected in parallel with the series circuit between this detection circuit E and the operation display circuit. Some devices were protected by a constant voltage element when a high voltage was applied to the device. Incidentally, 1 is an operation indicator light, and when the fire relay is touched, the contact 2 closes and current flows from the DC power source C through the fire relay, lighting it up and the fire relay is self-holding.

Accordingly, when the voltage of the DC power source C of the fire receiver A is higher than the constant voltage of the constant voltage element G of the fire detector D, the fire relay L and the constant voltage element G of the fire detector A are connected to each other by the DC power source C. For example, if a large number of fire detectors are connected to a fire receiver A and the fire relay is activated, it is necessary to determine which fire detector is inappropriate. In addition, since the fire relay does not operate when a current equal to the non-sensing current of the fire relay flows, there is a problem in that the current continues to flow through the fire relay and the constant voltage element.

(Purpose of the present invention) In view of the above-mentioned points, the present invention is designed to enable an operation display circuit to notify when the voltage of the DC power supply of the fire receiver A is higher than the constant voltage of the constant voltage element of the fire detector. For example, when a fire relay is activated by connecting multiple fire detectors to a fire receiver, it is possible to determine which fire detector is inappropriate, and when a current equal to the non-sensing current of the fire relay flows. The purpose of this is to reduce the amount of current that continues to flow.

(Embodiment) Below, the present invention will be explained based on FIG. 1, which shows an embodiment of the present invention. 1 is a fire receiver, 2 is a fire detector, and 3 is a connection between the fire receiver 1 and the fire detector 2. The fire receiver 1 consists of a series circuit 1c of a DC power supply 1a and a fire relay 1b.
The normally open contact 1d of the fire relay 1b and the operation indicator light 1
A series circuit with e is connected in parallel, and a detection circuit 2a that operates to switch from an OFF state to an ON state in response to a fire phenomenon of the fire detector 2 via a pair of sensing wires 3 to this parallel circuit, and this detection circuit 2a. A parallel circuit with a constant voltage element 2b that protects the device from failure from high voltage and a series circuit with an operation display circuit 2c that notifies the operation of the detection circuit 2a are connected in parallel. In addition, the minimum operating current of this operation display circuit 2c is the same as that of the fire relay 1b.
The current value is smaller than the minimum impressed current.

To explain this operating state, when the detection circuit 2a of the fire detector 2 is not operating, a signal is sent from the DC power supply 1a of the fire receiver 1 via the fire relay 1b and the operation display circuit 2c of the fire detector 2. A voltage is applied to the parallel circuit of the constant voltage element 2b and the detection circuit 2a. Incidentally, when this applied voltage becomes higher than the constant voltage of the constant voltage element 2b, the fire relay 1 is activated by the DC power supply 1a.
A current flows through the operation display circuit 2c, the operation display circuit 2c, and the constant voltage element 2b to operate the operation display circuit 2c and notify that an inappropriate voltage is being applied.

On the other hand, if the voltage of the DC power supply 1a is lower than the constant voltage of the constant voltage element 2b and the detection circuit 2a performs a switching operation in response to a fire phenomenon, the DC power supply 1a
A current flows through the fire relay 1b, the operation display circuit 2c, and the detection circuit 2c, and the operation display circuit 2c notifies the operation of the fire detector 2.
Touch b, close the normally open contact 1d, and turn on the operation indicator light 1.
e is operated, and the fire relay 1b is self-held from the DC power supply 1a via the fire relay 1b, the contact 1d, and the operation indicator light 1e.

(Effects) As described above, the present invention connects a constant voltage element in parallel to the detection circuit and sets the minimum operating current of the operation display circuit to a current value smaller than the minimum sensing current of the fire relay, so that the DC power supply of the fire receiver is reduced. When the voltage is higher than the constant voltage of the constant voltage element, it can be notified by the operation display circuit, and along with this, for example, when multiple fire detectors are connected to a fire receiver and the fire relay is activated, which fire detector is activated. It is possible to judge whether it is inappropriate or not, and it has the effect of reducing the amount of current that continues to flow when the current of the value of the non-sensing current of the fire relay flows.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the fire detector of the present invention, and FIG. 2 is a circuit diagram of a conventional fire detector. 1...Fire receiver, 1a...DC power supply, 1b...
...Fire relay, 1c...Series circuit, 1d...Contact, 1e...Operation indicator, 2...Fire detector, 2
a...detection circuit, 2b...constant voltage element, 2c...
Operation display circuit, 3...sensing line.

Claims (1)

[Scope of utility model registration request] In a fire detector, a series circuit consisting of a detection circuit that operates by switching in response to a fire phenomenon and an operation display circuit of this detection circuit is connected in parallel with a series circuit of a fire relay of a fire receiver and a DC power supply. A fire detector in which a constant voltage element is connected in parallel to the circuit, and the minimum operating current of the operation display circuit is set to a smaller current value than the minimum sensing current of the fire relay.