JP2018136809A - Repeater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a repeater capable of operating a relay so as to release the lock state of an electric lock when a receiver stops an operation while the relay does not operate with a transmission line short-circuited, even when using the relay for an operation of the electric lock.SOLUTION: A repeater 50 constituting a fire alarm system and the like includes: a voltage monitoring circuit 53 for monitoring a voltage of a transmission line; a transmission voltage drop determination circuit 51 for distinguishing/determining a short circuit of the transmission line and a voltage drop supplied from a receiver based on the output of the voltage monitoring circuit and for generating a control signal; and a latch type relay 57 for operating predetermined terminal equipment in a first state and a second state. The transmission voltage drop determination circuit generates a control signal for causing the latch type relay to be in a state before voltage drop detection when the transmission line is determined to be short-circuited, while generating a control signal for operating the latch type relay in a state different from the state before the voltage drop detection when determining there is a drop in the voltage supplied from the receiver.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a repeater used in a monitoring system such as a fire alarm system or a crime prevention system, and more particularly to a technique effective when used for a repeater having a transmission line short-circuit function and a relay control function.

  Conventionally, a fire alarm system is provided in a building to notify the occurrence of a fire. The fire alarm system receives fire alarms and fire transmitters equipped with pushbutton switches, fire alarm bells, indicator lights, smoke evacuation devices, fire prevention shutters, and other devices and detectors and transmitters. Receivers that output signals for operating bells, indicator lights, etc., and signals from fire detectors, bells, smoke evacuators, etc. in response to signals from detectors and between terminal equipment and receivers It consists of a repeater that converts signals between them. Here, the bell, the indicator lamp, and the repeater are generally configured to operate with electric power supplied from a receiver via a transmission line.

In addition, in the fire alarm system, when the transmission line is short-circuited, by detecting the short circuit and electrically disconnecting the transmission line on the downstream side, it is possible to avoid the situation where all the detectors do not operate, Some have an SCI (short circuit isolator).
On the other hand, in recent years, crime prevention systems in which an authentication device using an ID card or the like and an electric lock are combined to increase the security of offices and apartment buildings have become widespread. In addition, there is a system in which a fire alarm system and a crime prevention system are integrated and an electric lock is connected to a repeater of the fire alarm system.

  In a facility that employs a system having a fire monitoring function and a security function using an electric lock as described above, the receiver may stop operating due to a power failure or the like when the fire occurs, and the system may go down. At that time, if the system goes down while the electric lock is locked, there is a risk of hindering the smooth evacuation behavior of humans inside. Therefore, such a system is required to have a fail-safe function for releasing the lock state of the electric lock immediately before the system goes down. Therefore, in a system in which the electric lock is connected to the repeater, it is necessary to provide the failsafe function as described above in the repeater.

Some receivers are equipped with an auxiliary power supply (battery) so that they can operate even during a power outage. However, if the power outage lasts for a long time, the power supply voltage gradually decreases and the terminal is connected via the transmission line. The voltage supplied to equipment and repeaters also drops, leading to system down.
Conventionally, in a system equipped with a fire and gas detector and a security device, the security device is based on the detected temperature, smoke concentration, and carbon monoxide concentration, and has a plurality of preset security levels. An invention has been proposed in which any one of the above is determined, and the unlocking operation of the electric lock is performed when the determined security level is high (for example, Patent Document 1). Moreover, as invention regarding the fire alarm system provided with the repeater and SCI, there exist some which are described in patent document 2, for example.

JP 2002-8165 A JP 2007-323197 A

  By the way, in order to lock an electric lock and release a lock state in a system having a security function, an actuator such as a solenoid or a motor and an electromagnetic relay for passing a current to the actuator are generally used. And the electromagnetic relay for operating an electric lock needs to keep a state, even if a power supply or a monitoring system goes down.

  On the other hand, the present inventors detect the short-circuit when the transmission line is short-circuited, and electrically disconnect the downstream (short-circuited) transmission line to prevent the entire transmission line from functioning. Then, we examined a repeater with a fail-safe function that unlocks the electric lock when the transmission voltage drops. As a result, if the fail-safe function is activated due to a decrease in the transmission voltage, the relay will operate only when the receiver stops operating, and the transmission line will be It has become clear that there is a problem that the relay operates to release the lock state of the electric lock even when the short circuit occurs.

  The present invention has been made paying attention to the problems as described above. The purpose of the present invention is that even if a relay is used for operating an electric lock, the relay does not operate when the transmission line is short-circuited. An object of the present invention is to provide a repeater capable of releasing a lock state of an electric lock by operating a relay when the operation of a receiver is stopped.

In order to solve the above problems, the present invention provides:
A terminal having one or more terminal devices connected thereto, operated by receiving power from the receiver via a transmission line connected to the receiver, and connected to the terminal device connected to the terminal; A relay having a function of transmitting a signal received from the receiver via the transmission line,
A voltage monitoring circuit for monitoring the voltage of the transmission line;
A transmission voltage drop determination circuit that generates a control signal by distinguishing between a short circuit of the transmission line and a drop in the voltage supplied from the receiver based on the output of the voltage monitoring circuit;
A latch-type relay for operating a predetermined terminal device in a first state and a second state,
When the transmission voltage drop determining circuit determines that the transmission line is short-circuited, the transmission voltage drop determining circuit generates a control signal that causes the latch-type relay to be in a state before detecting a voltage drop, and the voltage supplied from the receiver is reduced. When it is determined that there is a control signal, a control signal for operating the latch-type relay in a state different from the state before the voltage drop is detected is generated.

  According to the above configuration, even if a latch-type relay is used for the operation of a terminal device such as an electric lock, the relay does not operate when the transmission line is short-circuited, and the receiver stops operating and is supplied from the receiver. When the applied voltage drops, the relay operates and the fail-safe function is activated to change the terminal device to a safe state.

Here, preferably, the transmission voltage drop determination circuit is the latch type when the voltage of the transmission line does not recover even after a predetermined time has elapsed after the voltage monitoring circuit detects the voltage drop of the transmission line. A control signal for operating the relay in a state different from the state before detecting the voltage drop is generated.
According to such a configuration, in a system in which the function of an SCI (short circuit isolator) is provided on the transmission line, the transmission line voltage is recovered by the SCI even if the transmission line is short-circuited. Later, if the transmission line voltage has not recovered after a predetermined time, it means that the receiver has stopped operating, so a control signal is generated to operate the latched relay in a state different from the state before the voltage drop was detected. By doing so, the fail-safe function works and the terminal device can be changed to a safe state.

Furthermore, preferably, a short-circuit protection circuit that is connected in series with the transmission line and that cuts off the transmission line when the voltage of the transmission line decreases based on the output of the voltage monitoring circuit,
The short-circuit protection circuit shuts off the transmission line both when the voltage monitoring circuit determines that the transmission line is short-circuited and when it is determined that the voltage supplied from the receiver is reduced. Try to maintain state.
According to such a configuration, since the repeater has an SCI (short circuit isolator) function, a circuit for detecting a voltage drop in the transmission line can be shared between the SCI function circuit and the fail-safe function circuit. By simply adding a simple circuit to the repeater, the number of SCIs provided on the transmission line can be reduced.

Further preferably, the predetermined terminal device is an electric lock.
According to such a configuration, when the operation of the receiver is stopped, the latch-type relay is activated, the fail-safe function is activated, and the lock state of the electric lock can be released.

  According to the present invention, even if a relay is used for the operation of the electric lock, the relay does not operate when the transmission line is short-circuited, and the relay operates to lock the electric lock when the receiver stops operating. There is an effect that a repeater capable of releasing the state can be realized.

It is a system configuration diagram showing an example of the configuration of a fire alarm system effective by applying the repeater according to the present invention. It is a block diagram which shows schematic structure of SCI (short circuit isolator). It is a block diagram which shows schematic structure of one Example of the repeater which concerns on this invention. The operation | movement of the repeater of an Example is shown, (A) is a timing chart at the time of short circuit generation of a transmission line, (B) is a timing chart at the time of a transmission voltage fall. The operation | movement of the repeater in another Example is shown, (A) is a timing chart at the time of short circuit generation of a transmission line, (B) is a timing chart at the time of transmission voltage fall.

Hereinafter, an embodiment of a repeater according to the present invention and a fire alarm system using the same will be described with reference to the drawings.
FIG. 1 shows a configuration example of a fire alarm system effective by applying a repeater according to the present invention.
The fire alarm system shown in FIG. 1 is connected to a fire receiver 10 that receives a signal from a sensor or transmitter and outputs a signal for operating a bell, an indicator lamp, or the like, and the fire receiver 10. A loop-shaped transmission line 20 and a plurality of fire detectors 31, a fire transmitter 32, an SCI 40, and a repeater 50 provided in the middle of the transmission line 20. The repeater 50 has a bell 61, a smoke exhaust device 62, Terminal devices such as a fire shutter 63 and an electric lock 64 are connected.

  The transmission line 20 is composed of two wires (signal line and common line). An operating voltage is supplied from the fire receiver 10 to the fire detector 31, the SCI 40, and the repeater 50 via the transmission line 20. In the system shown in FIG. 1, the transmission line 20 is arranged so as to form a loop when viewed from the fire receiver 10, but a terminator is provided at the end opposite to the fire receiver 10 and is unidirectional. Some systems are arranged as transmission lines.

  FIG. 2 shows a schematic configuration of the SCI 40. In FIG. 2, L1 is one wiring (signal line) constituting the transmission line 20, and L2 is the other wiring (common line) constituting the transmission line 20. The SCI 40 monitors the voltage of the pair of switch elements 41a and 41b provided in series with the line L2, the diodes 42a and 42b provided in parallel with the switch elements 41a and 41b, and the line L1, and the switch element 41a. , 41b, a control circuit 43 that generates a signal for controlling the on / off state, a constant voltage circuit 44 that receives the voltage from the wiring L1 of the transmission line 20 and generates the operating voltage of the control circuit 43, and the like. The control circuit 43 can monitor the voltage of the wiring L1 indirectly by monitoring the voltage from the constant voltage circuit 44.

  With the configuration as described above, for example, when a short circuit accident occurs on the transmission line 20 at a location as indicated by reference symbol A in FIG. 1, the voltage of the wiring L1 of the transmission line 20 decreases, so the control circuit 43 is short-circuited. Is detected and the switch elements 41a and 41b are turned off. Then, since the short-circuited part is disconnected from the fire receiver 10, the voltage of the wiring L1 of the transmission line 20 on the opposite side of the short-circuited part A rises, and the current flows through the diode 42a. The transmission line on the opposite side returns to a state where communication is possible, and the sensors and repeaters on the transmission line on the opposite side become operational and can continue to operate. The process from the occurrence of a short circuit to the return to a communicable state can be completed in a few ms (milliseconds).

As shown in FIG. 2, when the transmission line 20 is arranged in a loop shape, a voltage is supplied from the fire receiver 10 also from the opposite side of the transmission line 20, so that a short-circuited portion sandwiching the SCI 40. Sensors on the transmission line opposite A will also be operational.
In the SCI 40 in FIG. 2, FETs (field effect transistors) can be used as the switch elements 41a and 41b. In this case, parasitic diodes existing on the base of the FET are replaced with the diodes 42a and 42b in FIG. Can be used as

Next, the configuration and function of the repeater 50 will be described with reference to FIG.
As shown in FIG. 3, the repeater 50 of the present embodiment includes a CPU (central processing unit) and a memory such as a ROM and a RAM, and an MCU (microcomputer unit) that operates according to a program stored in the ROM. The control circuit 51, the constant voltage circuit 52 as a power supply device that receives the voltage from the wiring L1 of the transmission line 20 and generates the operating voltage of the internal circuit including the control circuit 51, and the voltage of the wiring L1 of the transmission line 20 A transmission voltage monitoring circuit 53 for monitoring is provided. The transmission voltage monitoring circuit 53 can be composed of, for example, a comparator or an AD conversion circuit, and the output of the transmission voltage monitoring circuit 53 is input to the control circuit 51 to determine whether or not the transmission voltage is equal to or lower than a predetermined voltage. Is done.

  Further, the repeater 50 of this embodiment is a terminal device such as a bell 61, a smoke exhaust device 62, or a fire shutter 63 connected to the repeater 50 for a signal received from the fire receiver 10 via the transmission line 20. A communication interface circuit 54 serving as a signal transmission circuit for transmission to the SCI, a short-circuit protection circuit 55 including a pair of switch elements 55a and 55b and diodes 56a and 56b similar to the SCI, and a signal for fail-safe to the electric lock 64 are output. A relay drive circuit (a pair of electromagnetic solenoids) 57a and a contact 57b. A relay output circuit 57 is configured by the relay drive circuit (a pair of electromagnetic solenoids) 57a and the contact 57b. In this embodiment, a latching relay is used as the relay output circuit 57.

  Note that when the control circuit 51 detects a short circuit of the transmission line 20, the switch elements 55 a and 55 b are controlled to be in an off state, similarly to the SCI. On the other hand, the relay output circuit 57 is configured to be controlled based on the determination result of the transmission voltage by the control circuit 51. The short-circuit protection function of the transmission line 20 can be omitted. As will be described later, the repeater 50 according to the present embodiment has a function of distinguishing and detecting a short circuit of the transmission line 20 and a decrease in the transmission voltage. Therefore, the short circuit protection circuit 55 is detected when a short circuit of the transmission line 20 is detected. Thus, the SCI function can be added without separately providing a circuit for controlling the short-circuit protection circuit 55, thereby reducing the number of SCI provided independently.

Further, the repeater 50 of this embodiment is provided with a setting device 58 that can switch whether the fail-safe function by the control circuit 51 and the relay output circuit 57 is enabled or disabled from the outside.
In the repeater 50 of the present embodiment, the latching relay is activated when the battery of the fire receiver 10 is lowered due to the fail-safe function and the operation is stopped, and the voltage supplied via the transmission line is lowered. Thus, the lock state of the electric lock can be released. Moreover, in the repeater 50 of this embodiment, when the transmission line 20 is short-circuited and the transmission voltage is temporarily lowered, the latching relay does not operate and the lock state of the electric lock is not released. It has become.

Next, the control operation of the repeater 50 when the voltage of the transmission line is lowered by the control circuit 51 will be described using the timing chart of FIG. 4A shows a case where a short-circuit accident has occurred in the transmission line, and FIG. 4B shows a case where the transmission voltage from the fire receiver 10 has dropped.
In the repeater 50 of this embodiment, as shown in FIGS. 4A and 4B, the transmission voltage drops below a predetermined detection level VthL and the output of the voltage monitoring circuit (comparator) 53 changes from high level to low level. If the output of the transmission voltage monitoring circuit (comparator) 53 remains at a low level even after the predetermined time Td1 has elapsed since the control circuit 51 detects that the change has occurred (timing t1), the control of the short circuit protection circuit 55 is performed. The signal is lowered to turn off the switch elements 55a and 55b of the short circuit protection circuit 55, and the downstream transmission line is disconnected (timing t2).

  More specifically, when the output of the voltage monitoring circuit (comparator) 53 changes from a high level to a low level (t1), a voltage check request is generated by the control circuit 51 to check the output of the transmission voltage monitoring circuit 53. , The voltage check request is generated again after T1 (for example, 0.5 ms), and if the output of the transmission voltage monitoring circuit 53 is confirmed to be low level twice in succession, the short circuit protection circuit 55 of T2 (for example, about 1 ms) is confirmed. The control signal is lowered to disconnect the downstream transmission line (timing t2).

  When a short circuit occurs, after the transmission line is disconnected by the short circuit protection, the transmission voltage is recovered unless the local station is short-circuited. Then, when the transmission voltage monitoring circuit 53 detects that the return detection level VthH has been exceeded, the output changes from the low level to the high level (t3), and in response to this, the control circuit 51 generates a voltage check request. When the output of the transmission voltage monitoring circuit 53 is checked and a voltage check request is generated again after T1, and it is confirmed that the output of the transmission voltage monitoring circuit 53 is at a high level twice in succession, a short circuit has occurred in the transmission line. To be judged. Therefore, the relay control pulse UP is not generated, and the relay output is kept at the low level (electric lock: closed side).

  On the other hand, the control signal of the short circuit protection circuit 55 is lowered to turn off the switch elements 55a and 55b of the short circuit protection circuit 55, and the downstream transmission line is disconnected (timing t2), and then a predetermined time Td2 has elapsed. At (timing t4), as shown in FIG. 4B, when it is detected that the output of the transmission voltage monitoring circuit (comparator) 53 is continuously at a low level twice, the transmission voltage is lowered. The control signal UP for the relay output circuit 57 is raised. As a result, the relay output is changed to a high level, the latching relay is activated, and the electric lock is unlocked. The predetermined time Td2 may be set to a time slightly longer than the required operation time (30 ms) of the short circuit protection circuit 55.

(Second embodiment)
Next, a method for controlling the output circuit when the terminal device connected to the repeater 50 is an alarm device such as a bell will be described. In the case of such a device, the control logic is opposite to that of the above embodiment, and if the transmission line is short-circuited during an acoustic ringing, the acoustic ringing is continued while the fire receiver is down during the ringing. When the transmission voltage drops due to this, it is necessary to control to stop ringing. Further, in the case of an alarm device such as a bell, the control is not performed by contact output by the relay of the above embodiment, but by turning on / off a voltage output such as 24V. A latching relay is used to turn this voltage output (24V) on and off.

FIG. 5 shows an example of a timing chart of the control operation of the repeater 50 when the transmission voltage drops in the repeater 50 to which the above devices are connected. 5A shows a case where a short-circuit accident has occurred in the transmission line, and FIG. 5B shows a case where the transmission voltage from the fire receiver 10 has dropped.
In this embodiment, as shown in FIGS. 5A and 5B, the output voltage of the voltage monitoring circuit (comparator) 53 changes from the high level to the low level as the transmission voltage falls below the predetermined detection level VthL. If the output of the transmission voltage monitoring circuit (comparator) 53 remains low even after a predetermined time Td1 has elapsed since the control circuit 51 detected (timing t1), the control signal of the short circuit protection circuit 55 is lowered. Then, the switch elements 55a and 55b of the short-circuit protection circuit 55 are turned off, and the downstream transmission line is disconnected (timing t2).

  When a short circuit occurs during sounding, the transmission voltage is recovered after the transmission line is disconnected by short circuit protection and the local station is not short circuited. Then, when the transmission voltage monitoring circuit 53 detects that the return detection level VthH has been exceeded, the output changes from the low level to the high level (t3), and in response to this, the control circuit 51 generates a voltage check request. When the output of the transmission voltage monitoring circuit 53 is checked and a voltage check request is generated again after T1, and it is confirmed that the output of the transmission voltage monitoring circuit 53 is at a high level twice in succession, a short circuit has occurred in the transmission line. To be judged. Therefore, the relay control pulse UP is not generated, the output circuit control signal is kept at the high level, and the latching relay is kept closed (alarm device: sounding sound).

  On the other hand, a drop in transmission voltage occurs during sounding, the control signal of the short-circuit protection circuit 55 is lowered, the switch elements 55a and 55b of the short-circuit protection circuit 55 are turned off, and the downstream transmission line is disconnected ( After the timing t2), when a predetermined time Td2 has passed (timing t4), as shown in FIG. 5B, it is detected that the output of the transmission voltage monitoring circuit (comparator) 53 is continuously at a low level twice. If so, it is determined that the transmission voltage has dropped, and the control signal LP for the relay output circuit 57 is raised. As a result, the output circuit control signal changes to a low level, the latching relay is switched to the open side, and the alarm stops sounding.

As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to the thing of the said embodiment. For example, in the fire alarm system of the above embodiment, only the fire detector is connected to the transmission line as a detection. A vessel may be connected.
In the above embodiment, the electric lock is described as an example of the terminal device that is subject to fail-safe control. However, the target terminal device is not limited to the electric lock, and may be other equipment or devices such as a fire door. Also good.

  Furthermore, in the above embodiment, the case where the present invention is applied to a fire alarm system provided with a fire receiver has been described. However, the present invention is not limited to a fire alarm system, and monitoring targets such as a disaster prevention monitoring system and a crime prevention system can be used. The present invention can be widely used in general systems including a plurality of terminal devices arranged in an area and a receiver that receives signals from the terminal devices.

10 Receiver 20 Transmission Line 31 Fire Detector 32 Transmitter 40 SCI (Short Circuit Isolator)
50 repeater 51 control circuit 53 transmission voltage monitoring circuit (comparator)
55 Short-circuit protection circuit 64 Terminal equipment (electric lock)

Claims (4)

A terminal having one or more terminal devices connected thereto, operated by receiving power from the receiver via a transmission line connected to the receiver, and connected to the terminal device connected to the terminal; A relay having a function of transmitting a signal received from the receiver via the transmission line,
A voltage monitoring circuit for monitoring the voltage of the transmission line;
A transmission voltage drop determination circuit that generates a control signal by distinguishing between a short circuit of the transmission line and a drop in the voltage supplied from the receiver based on the output of the voltage monitoring circuit;
A latch-type relay for operating a predetermined terminal device in a first state and a second state,
When the transmission voltage drop determining circuit determines that the transmission line is short-circuited, the transmission voltage drop determining circuit generates a control signal that causes the latch-type relay to be in a state before detecting a voltage drop, and the voltage supplied from the receiver is reduced. A repeater configured to generate a control signal for operating the latch-type relay in a state different from a state before voltage drop detection when it is determined that there is a voltage drop.   The transmission voltage drop determination circuit detects the latch relay before the voltage drop is detected when the voltage monitoring circuit does not recover the voltage of the transmission line even after a predetermined time has elapsed after detecting the voltage drop of the transmission line. The repeater according to claim 1, wherein the repeater is configured to generate a control signal that operates in a state different from the state of the relay. A short-circuit protection circuit that is connected in series with the transmission line and that cuts off the transmission line when the voltage of the transmission line is reduced based on the output of the voltage monitoring circuit,
The short-circuit protection circuit shuts off the transmission line both when the voltage monitoring circuit determines that the transmission line is short-circuited and when it is determined that the voltage supplied from the receiver is reduced. The repeater according to claim 1 or 2, wherein the state is maintained.   The repeater according to claim 1, wherein the predetermined terminal device is an electric lock.

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