JPH0570880B2 - - Google Patents

Description

[Detailed description of the invention] 【Technical field】

The present invention relates to a storage type fire receiver that provides fire alarm.

[Background technology]

A self-fire alarm system connects a fire detector that detects fire from smoke and heat to the detector line of the fire receiver.
DC voltage is applied from the fire receiving circuit installed in the fire receiver to the detector line, and when the fire detector detects a fire, the signal lines of the detector line are almost short-circuited (the voltage of the detector line is low voltage) and sends a fire signal to the fire receiving circuit. In the storage type fire receiver of this type of fire alarm system, when a fire signal from a fire detector is received, it does not immediately determine that there is a fire, but rather for a certain period of time from the time the first fire signal is received. Every time a fire signal is received from a fire detector, the fire detector performs so-called recovery control to cancel the state in which it has detected a fire and return it to a state in which it can newly detect a fire (standby state). When a fire signal is received from the fire detector again after a certain period of time has elapsed, a so-called accumulation operation is performed to determine that there is a fire, thereby minimizing the possibility of false alarms due to malfunction of the fire detector. Note that, generally, when a fire signal is received from the fire detector again within a predetermined period after a certain period of time has elapsed, it is determined that there is a fire. As shown in FIG. 2, this type of fire receiver A transmits a fire signal from a fire detector 1 to a detector line
A fire reception circuit 4 receives power through the fire reception circuit 4, a power supply circuit 2 that supplies power to the fire reception circuit 4, and a contact point in the power supply path from the power supply circuit 2 to the fire reception circuit 4.
When r ₁ is inserted, fire receiving circuit 4 is activated by opening and closing contact r ₁ .
Interrupting relay Ry ₁ that controls the power supply to
, a fire signal detection circuit 5 that detects the signal from the fire detector 1 earlier than the fire reception circuit 4; and a first circuit that measures a certain period of time from when the fire signal is first detected by the fire signal detection circuit 5. A fire signal is detected in the fire signal detection circuit 5 between the timer circuit 6 of the first timer circuit 6, the second timer circuit 7 which measures a certain period of time after the elapse of the timer period of the first timer circuit 6, and the fire signal detection circuit 5 during the timer period of the first timer circuit 6. Each time it is detected, the above-mentioned shutoff relay is activated.
Ry ₁ is controlled to temporarily stop the power supply from the power supply circuit 2 to the fire reception circuit 4 , temporarily stop the fire signal reception operation of the fire reception circuit 4 , and the second timer circuit 7 and a driving means for continuously supplying power from the power supply circuit 2 to the fire reception circuit 4 without controlling the cutoff relay Ry ₁ during the measurement period. Here, the driving means includes a transistor Q ₁ connected to both ends of the power supply circuit 2 in series with the relay Ry ₁ .
and a one-shot generating circuit 8 which temporarily turns on the transistor _Q1 every time a fire signal is detected by the fire signal detection circuit 5 during the counting period of the first timer circuit 6. The relay Ry ₁ is such that its contact r ₁ is switched to the terminal a side when the transistor Q ₁ is off and not driven. Therefore, when the transistor Q ₁ is off, power is supplied from the power supply circuit 2 to the fire reception circuit 4 . Also, during driving when transistor Q ₁ is on, contact r ₁ is switched to terminal b,
The power supply to the fire receiving circuit 4 is cut off. The operation of the storage type fire receiver described above is as follows. During normal operation, when the fire detector 1 does not detect a fire, the contact r ₁ of the relay Ry ₁ is switched to the terminal a side, and power is supplied to the fire receiving circuit 4 via the fire receiving circuit 4. At this time, a voltage is applied from the fire receiving circuit 4 to the detector line 1, and the fire detector 1 is in a state of monitoring the fire. If a fire is detected by the fire detector 1, then a fire signal shown in FIG. 3a is inputted to the fire receiver A via the detector line l.
Here, the fire detector 1 puts the detector line 1 into a substantially short-circuited state and gives a fire signal to the fire receiver A in a so-called current mode. Note that the high level state in FIG. 3a indicates that the fire detector 1 is in a substantially short-circuited state with the sensor line l. This fire signal is detected by the fire signal detection circuit 5 before being received by the fire reception circuit 4. Depending on the output given from the fire signal detection circuit 5 at this time, the one shot generation circuit 8
Turn on _Q1 one shot (temporarily).
By turning on the transistor _Q1 , the relay _Ry1 is driven, and the contact _r1 is temporarily switched to the terminal b side, and during the period when the contact _r1 is switched to the terminal b side, the fire reception circuit 4 is Power supply is stopped. When the power supply to the fire receiving circuit 4 is stopped in this way, the voltage is no longer applied to the detector line l, so the fire detection state of the fire detector 1 is canceled (similar detectors at the time of fire monitoring The state returns to a state in which the line 1 is not short-circuited). Here, in order to restore fire detector 1, the state of voltage application to detector line l is released (no voltage is applied), which is self-maintaining with a thyristor like a smoke detector. This is because in the case where the sensor line 1 is not applied to the sensor line 1, the state cannot be returned to the restored state unless the voltage application state to the sensor line 1 is once released. Then, by turning off transistor Q ₁ , relay Ry ₁ returns to the non-driving state, and contact r ₁ is switched to terminal a side, thereby stopping power supply from power supply circuit 2 to fire reception circuit 4. will be resumed. Therefore, a voltage is also applied to the sensor line l, and the normal fire monitoring situation is restored. In other words, the fire signal is not received by the fire receiving circuit 4, and the state returns to a new fire monitoring state.
Therefore, no fire alarm is issued at this time. By the way, when the first fire signal is detected by the fire signal detection circuit 5 as described above, the first timer circuit 6 starts a time counting operation for a certain period of time as shown in FIG. 3b based on the output thereof. Note that the high level period in FIG. 3b indicates the time period of the first timer circuit 6. During the timekeeping operation period of this first timer circuit 6,
Even if a fire signal is received from the fire detector 1, the fire signal receiving operation of the fire receiving circuit 4 is stopped by repeating the same operation as described above, and therefore no fire alarm is issued. Then, when the time counting operation of the timer circuit 6 is completed, from that point on, the second timer circuit 7 starts operating as shown in FIG.
Start the timing operation as shown in . The operation of the one-shot generating circuit 8 is stopped by the output of the second timer circuit 7 at this time. In other words, even if the fire signal from the fire detector 1 is detected by the fire signal detection circuit 5 during the timing operation period of the second timer circuit 7, the one shot generation circuit 8 does not receive the output of the fire detection circuit 5. Does not generate an output that turns on transistor _Q1 . Therefore, power is continuously supplied to the fire receiving circuit 4, and the fire signal from the fire detector 1 is received by the fire receiving circuit 4. At this time, the fire receiver A issues the fire alarm for the first time, as shown in FIG. 3e. The above-mentioned operation is called an accumulation operation of the fire receiver A, and thereby prevents malfunctions due to transient noise or the like. By the way, in the above-mentioned storage type fire receiver, if a contact switching abnormality of relay Ry ₁ occurs due to a failure in which transistor Q ₁ continues to be turned on or an abnormality in which contact r ₁ is maintained switched to terminal b side, a fire may occur. No power is supplied to the receiving circuit 4,
There is a problem in that the fire monitoring operation of the storage type fire receiver is completely stopped. Here, this type of fire receiver is generally equipped with a plurality of sensor lines l, and when all these sensor lines l are operated for accumulation at once, the operation frequency becomes high, and the contact point of relay Ry ₁ There was a problem that the possibility of contact switching abnormality occurring in _r1 was increased.

[Purpose of the invention]

The present invention has been made in view of the above points, and its purpose is to provide a storage type fire receiver that detects relay contact switching abnormalities and prevents situations in which fire monitoring cannot be performed. It is about providing.

[Disclosure of the invention]

(Example) FIG. 1 shows an example of the present invention.
Basically, similar to what was explained in FIG. 2, there is a fire receiving circuit 4 that receives a fire signal from the fire detector 1 via the detector line l, and a power supply circuit that supplies power to the fire receiving circuit 4. 2, a cutoff relay Ry ₁ having a contact r ₁ inserted in the power supply path from the power supply circuit 2 to the fire receiving circuit 4, and controlling the supply of power to the fire receiving circuit 4 by opening and closing the contact r ₁ ; A fire signal detection circuit 5 detects the fire signal from the fire detector 1 earlier than the fire reception circuit 4; A fire signal is detected by the fire signal detection circuit 5 between the timer circuit 6 and the second timer circuit 7 that measures a certain period of time after the elapse of the time period of the first timer circuit 6 and the time period of the first timer circuit 6. Each time, the cutoff relay Ry ₁ is controlled to temporarily stop the power supply from the power supply circuit 2 to the fire reception circuit 4, and the fire signal reception operation of the fire reception circuit 4 is temporarily stopped. A relay for stopping the second timer circuit 7 and interrupting the timing of the second timer circuit 7
A transistor _Q1 and a one-shot generating circuit 8 are provided as driving means for continuously supplying power from the power supply circuit 2 to the fire reception circuit 4 without controlling _Ry1 . In this embodiment, in addition to the above configuration, an abnormality detection means is provided for detecting an abnormality in which power cannot be supplied to the fire reception circuit 4 due to the contact _r1 of the cutoff relay _Ry1 not being switched. an abnormality detection circuit 10 as an abnormality detection circuit 10, and a contact _r2 that bypasses the contact r1 of the cutoff relay Ry ₁ and supplies power from the power supply circuit 2 to the fire reception circuit 4 when the abnormality detection circuit ₁₀ detects an abnormality. It is equipped with relay Ry ₂ for bypass. Contact r ₂ of relay Ry ₂ for bypass is the relay
This is a so-called normally open contact that is in an open state when Ry ₂ is not driven, and is connected to connect the common terminal of contact r ₁ of interrupting relay Ry ₁ to terminal a. The abnormality detection circuit 10 includes a transistor Q ₂ and a resistor.
It consists of R ₁ , R ₂ , and capacitor C ₁ . Transistor Q ₂ is connected to both ends of power supply circuit 2 together with relay Ry ₂ for bypass, and when turned on, drives relay Ry ₂ to close contact r ₂ . Note that a light emitting diode LD is connected to the relay Ry ₂ . Resistors R ₁ and R ₂ are contacts of relay Ry ₁ for breaking
The capacitor C 1 is connected in series between the terminal b of r ₁ and the negative pole of the power supply circuit 2, and the capacitor C ₁ is connected in parallel to both ends of the resistor R ₂ , and the connection point of the resistors R ₁ and R ₂ is connected to the base of the transistor Q ₂ . It is connected to the. The operation related to the characteristic configuration of this embodiment described above is as follows. Now, in the storage operation explained in the conventional example, when contact r ₁ of cutoff relay Ry ₁ is switched to terminal b side, a contact switching error occurs in which contact r ₁ cannot be switched to terminal a side. Then, the capacitor C ₁ is charged by the power supply circuit 2 via the resistor R ₁ . When the voltage across capacitor _C1 exceeds the threshold voltage (base-emitter voltage) of transistor _Q2 , transistor _Q2 turns on. By turning on the transistor Q ₂ , the bypass relay Ry ₂ is driven and the contact r ₂ is closed. As a result, power is supplied from the power supply circuit 2 to the fire reception circuit 4. After that, no storage operation is performed, but fire monitoring becomes possible. Therefore, it is possible to prevent the intellectual problem of missed notifications. Here, when the relay Ry ₂ is driven, that is, when the transistor Q ₂ is on, a light emitting diode LD connected in parallel to the relay Ry ₂ is generated.
This causes an abnormality in the storage type fire receiver, which indicates that it is operating in an emergency state and alerts the user. In addition, when the storage type fire receiver is performing normal storage operation, the voltage across capacitor C ₁ is equal to the threshold voltage of transistor Q ₂ during the time when contact r ₁ is switched to terminal b side. The time constants of resistor R ₁ and capacitor C ₁ are set so that the voltage will not be exceeded. Therefore, transistor _Q2 is never turned on during normal storage operation.

【Effect of the invention】

As described above, the present invention includes a fire reception circuit that receives a fire signal from a fire detector that detects fire from smoke or heat via a detector line, a power supply circuit that supplies power to the fire reception circuit, and a power supply circuit that supplies power to the fire reception circuit. A contact is inserted into the power supply path from the circuit to the fire receiving circuit, and a cutoff relay controls the supply of power to the fire receiving circuit by opening and closing the contact, and a relay that controls the supply of power to the fire receiving circuit by opening and closing the contact, and a relay that transmits the fire signal from the fire detector to the fire receiving circuit. A fire signal detection circuit that detects fire quickly, a first timer circuit that measures a certain period of time from when the fire signal is first detected by this fire signal detection circuit, and a certain period of time after the time period of the first timer circuit has elapsed. and a second timer circuit for timing, and each time a fire signal is detected by the fire signal detection circuit during the time period of the first timer circuit, the cutoff relay is controlled to disconnect the power from the power supply circuit to the fire reception circuit. The power supply is temporarily stopped, the fire signal receiving operation of the fire receiving circuit is temporarily stopped, and the second
In the storage type fire receiver, the contact point of the cut-off relay is switched, and the storage type fire receiver is equipped with a drive means that continuously supplies power from the power supply circuit to the fire receiving circuit without controlling the cut-off relay at the time measured by the timer circuit. An abnormality detection means detects an abnormality in which power cannot be supplied to the fire receiving circuit due to a fire failure, and when the abnormality detection means detects an abnormality, the contact point of the cutoff relay is bypassed and a fire is detected from the power supply circuit. Since it is equipped with a bypass relay that has a contact that supplies power to the receiving circuit, it can detect when a contact switching abnormality occurs in the cutoff relay that cannot supply power to the fire receiving circuit. Power can be supplied from the power supply circuit to the fire receiving circuit through the bypass relay contact, and the storage type fire receiver can be prevented from becoming inoperable.
This has the effect of improving the operational reliability of the storage type fire receiver without causing the intellectual problem of missed alarms.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing an embodiment of the present invention;
FIG. 2 is a circuit configuration diagram showing a conventional example, and FIG. 3 is an explanatory diagram of the same operation. A is a storage type fire receiver, 1 is a fire detector, 2 is a power supply circuit, 4 is a fire reception circuit, 5 is a fire signal detection circuit, 6 is a first timer circuit, 7 is a second timer circuit, 8 is a 10 is a one-shot generating circuit, 10 is an abnormality detection circuit, Ry ₁ and Ry ₂ are relays, Q ₁ and Q ₂ are transistors, r ₁ and r ₂ are contacts, and l is a sensor line.

Claims (1)

[Scope of Claims] 1. A fire reception circuit that receives a fire signal from a fire detector that detects fire from smoke or heat via a sensor line, a power supply circuit that supplies power to the fire reception circuit, and a power supply circuit. A contact is inserted into the power supply path from the fire detector to the fire receiver circuit, and a cutoff relay controls the supply of power to the fire receiver circuit by opening and closing the contact, and a relay that transmits the fire signal from the fire detector earlier than the fire receiver circuit. A fire signal detection circuit that detects a fire signal, a first timer circuit that measures a certain period of time from when the fire signal is first detected by this fire signal detection circuit, and a certain period of time that elapses after the time period of the first timer circuit has elapsed. Every time a fire signal is detected by the fire signal detection circuit between the second timer circuit that measures time and the first timer circuit, the cutoff relay is controlled to supply power from the power supply circuit to the fire reception circuit. The power supply circuit temporarily stops the fire signal reception operation of the fire reception circuit, and the fire reception circuit is switched from the power supply circuit to the fire reception circuit without controlling the cutoff relay during the timing of the second timer circuit. An abnormality that detects an abnormality in which power cannot be supplied to the fire receiving circuit due to the disconnection relay contact not being switched in a storage type fire receiver equipped with a drive means for continuously supplying power to the fire receiving circuit. An accumulation type fire comprising a detection means and a bypass relay having a contact that bypasses the contact of the cutoff relay and supplies power from the power supply circuit to the fire receiving circuit when the abnormality detection means detects an abnormality. Receiving machine. 2. The storage type fire receiver according to claim 1, comprising an indicator such as a light emitting diode that indicates that the cutoff relay is in an abnormal state when the abnormality detection means detects an abnormality.