JP2724199B2 - sensor - Google Patents

Description

The present invention relates to a plurality of sensors connected to a P-type receiver and capable of being tested remotely.

[Conventional technology and problems] When a plurality of sensors are connected to a fire receiver via a transmission line, and a detector detects an abnormality, a switching circuit in the detector that detects the abnormality operates and is short-circuited. There is known a so-called P-type fire alarm device in which a signal is transmitted to a fire receiver so that the receiver can know the occurrence of a fire.

When performing an operation test of a fire detector in such a P-type fire alarm device, a test device is connected to the receiver side, and the test device is connected to a specific fire detector via a transmission line. Then, an operation test signal for operating the switching circuit is transmitted to cause the short circuit signal to be transmitted to the transmission line in the specific sensor, and the short circuit signal is transmitted from the specific sensor on the tester side. In some cases, the quality of the test result is determined by determining whether or not the test result has been transmitted.

In the case of this method, since each sensor that performs a test performs the same operation as when a real fire occurs and transmits a short-circuit signal to the transmission line, even a receiver that receives the short-circuit signal A fire operation including a fire display in response thereto is performed. This is good when it is desired to perform even a fire display test or the like in the receiver, but otherwise, the test takes a long time. That is, in order to perform the operation test of the next another sensor, first, the receiver is manually restored, and the sensor voltage is lowered across the transmission line during operation. It has to wait for a certain time, for example, 7 to 8 seconds, until it stabilizes.

Therefore, when performing an operation test on a large number of sensors, there is a problem that the recovery operation is not only troublesome but also requires a long time. For example, Then, the time to test 500 sensors is 10 (seconds)
× 500 (pieces) = 5,000 (seconds), which means that a very long time is required for the test.

[Means for Solving the Problems] Therefore, an object of the present invention is to improve the efficiency of the operation test and to improve the efficiency of the operation test when remotely performing the operation test of the fire detector connected to the P-type receiver. In particular, it is an object of the present invention to provide a sensor capable of performing an operation test on all elements in the sensor in a relatively short time.

For this reason, according to the present invention, in a sensor including an output circuit that sends an abnormal signal through the transmission line by closing the transmission line and short-circuiting the transmission line when the abnormality is detected, A resistor inserted in series in the output circuit in response to a test command signal sent out to prevent the transmission line from being short-circuited when the output circuit is closed. A resistance, and returning the test result signal in response to the test command signal via the transmission line to determine whether the output circuit has been closed by an operation test performed in response to the test command signal. And a determining means for determining whether or not the sensor is provided.

[Operation] Since a resistor is inserted in series in the output circuit in response to the test command signal transmitted through the transmission line, during the test, the resistance is output by an operation test performed in response to the test command signal. Even if the circuit is closed, the transmission line will not be short-circuited. Thus, the transmission of the abnormal signal through the transmission line is prevented.

The determining means determines whether or not the output circuit has been closed based on the operation state performed in response to the test command signal, and the result is returned as a test result signal via the transmission line.

Since the signal returned via the transmission line is not a short-circuit signal as an abnormal signal but a test result signal, the receiver is not operated and there is no need for a recovery operation, so that the test time can be reduced. . Further, at the time of the test, the output circuit is also tested by determining the closed state of the output circuit by the determination means, so that a highly accurate test can be performed for all the elements in the sensor.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block circuit diagram showing an internal circuit of a sensor according to an embodiment of the present invention, taking a scattered light type smoke detector as an example. Of course, the present invention is not limited to a smoke sensor, but can be applied to various sensors such as a heat sensor and a gas sensor.

In FIG. 1, terminals T ₁ and T ₂ of a microprocessor MPU have a monitoring drive circuit DR ₁ for driving a light emitting element LED ₁ for monitoring and a test drive for driving a light emitting element LED ₂ for testing, respectively. and circuit DR ₂ are shown connected. The microprocessor MPU outputs a light emission control signal for monitoring operation or test operation to these drive circuits, respectively. The microprocessor MPU also has
The output of the amplifier AMP that amplifies the output of the light receiving element PD is connected to the terminal T ₃
Together they are connected at fire decision circuit FDC for performing fire determination are connected in the terminal T ₄ by the output from the amplifier AMP. Terminal T ₄ of the microprocessor MPU
Outputs a synchronization signal to the fire determination circuit FDC.

The drive circuits DR ₁ , DR ₂ , light emitting elements LED ₁ , LED ₂ ,
Sensor section SE with PD PD, amplifier AMP, FDC
Is composed.

The signal transmitting and receiving circuit SRC is connected between the transmission line C-L and the terminal T ₅ of the microprocessor MPU to perform transmission and reception of signals to and from the receiver (not shown) via the transmission line C-L ing. Power is also supplied from the receiver via the transmission line CL, so that the transmission line CL has a constant voltage circuit CV.
C is also shown connected.

An output circuit OTC including resistors R ₁ , R ₂ , R ₃ , an operation display light emitting element LED ₃ , an operation switching circuit SW ₁ , and a test switch element SW ₂ closed during monitoring and opened during testing.
Are connected between the transmission lines CL so as to output a short-circuit signal to the receiver when the detector operates. The terminal T _{6 of the} microprocessor MPU is connected to the switch element SW _{2 of the} output circuit OTC.
Are connected to, together with the time of the test and outputs the opening command to the switch element SW _2, the terminal T ₇ is to receive a signal representing the operation signal or closed state from the output circuit OTC during operation of the sensor It is connected to the output circuit OTC.

The operation of the sensor shown in FIG. 1 will be described with reference to the timing chart shown in FIG.

First, when describing the operation in the normal monitoring, the switch element SW ₂ in the output circuit OTC is closed by a command from the terminal T ₆ of the microprocessor MPU (second
SW ₂ on in the figure), and the microprocessor MPU is connected to terminal T ₁
Is performed every predetermined time interval INT, for example the output to operation of the light emitting element LED ₁ a light emission control signals S ₁ every 4 seconds for monitoring the drive circuit DR ₁ from. Light emitting device LED ₁
And the light receiving element PD are arranged such that, when smoke exists between the two, the light from the light emitting element LED ₁ is reflected according to the smoke density existing between the two to reach the light receiving element PD, Therefore, when there is smoke between them, when the light emitting element LED ₁ for monitoring emitted at time t ₁ as shown in FIG. 2, the light receiving element PD receives the reflected light corresponding to the smoke density To output a light receiving signal to the amplifier AMP.

Received signal amplified by the light receiving by the amplifier AMP in the light receiving element PD, with given to the terminal T ₃ of the microprocessor MPU, also given fire decision circuit FDC where fire determination is made, the smoke density and fire abnormal If is sufficient to the signal S ₂ shown at time t ₂ from the terminal Tcc of said fire determining circuit FDC a (FIG. 2) fire abnormality is output.

Fire abnormality signal output from the terminal Tcc fire decision circuit FDC is given to the switching circuit SW ₁ in a conductive state the switching circuit SW _1, the transmission line C-L that is connected from this by a non-illustrated receiver , The light emitting element LED ₃ for operation display, the resistors R ₂ , R ₃ , and the switch element SW ₂ which is closed in the normal monitoring state are short-circuited, thus causing a fire on the receiver side. A short-circuit signal indicating that an abnormality has occurred is sent.

In this case, since the connection point of the resistors R ₂ and R ₃ in the output circuit OTC is connected to the terminal T ₇ of the microprocessor MPU, knows that the output circuit OTC in the microprocessor MPU is time t ₂ is operated it can. The second figure, since the switch element SW ₂ is closed, a v ₀ is the potential at terminal T ₇ of the fires not abnormal, the potential at the terminal T ₇ when the fire abnormality has occurred in the v ₁ It is shown as is.

Thus, receiving the operation signal of the output circuit OTC microprocessor MPU to the terminal T _7, also, since the output of the amplifier AMP is applied to the terminal T ₃ of the microprocessor MPU, thereby the microprocessor MPU is necessary when receiving the operation signal to the terminal T _7, the terminal T ₃ from the amplifier AMP
The smoke density signal of an analog given to, by adding a self-address, the signal transmitting and receiving circuit SR from the terminal T ₅
It is also possible to notify the receiver side via the transmission line CL via C.

First test command signal from the unillustrated receiver of the tester or the like when performing tests been sent it is received at the terminal T ₅ of the microprocessor MPU through the signal transmitting and receiving circuit SRC.

When it microprocessor MPU receives a signal which it determines that it is a test command signal, first, outputs (Figure 2) at time t ₃ the opening command from the terminal T ₆ the switch element SW _2, which the switch element SW ₂ is opened by. Next, the microprocessor MPU causes the light emitting element LED ₂ for output to the test drive command S ₃ at time t ₄ to the test drive circuit DR ₂ from the terminal T _2.

The test light emitting element LED ₂ is arranged at such a position that when the test light emitting element LED ₂ emits light, the light receiving element PD receives a sufficient amount of light to generate a fire abnormality signal.
When the test light emitting element LED ₂ are emitted by the drive command S _3,
Receiving signals received by the light receiving element PD is amplified by the amplifier AMP is supplied to the terminal T ₃ and a fire determining circuit FDC microprocessor MPU, as the test result signal at time t ₅ from the terminal Tcc fire decision circuit FDC fire abnormality signal S ₂ of are output. Next, the fire alarm signal i.e. the test result signal S ₂ is supplied to the output circuit OTC switching circuits SW ₁ to conduct the switching circuit SW _1.

During the test, since the switch element SW ₂ is open, the further resistor to the output circuit OTC compared to normal monitoring R
₁ is inserted in series, the resistor R _1, since a sufficiently high resistance to not short-circuit the transmission line C-L, is not a short circuit signal is sent to the receiver side.

However, the potential of the connection point of the output circuit OTC resistor R ₂ and R ₃ the switching circuit SW ₁ is in a conductive state, decreases at time t ₅ as shown in FIG. 2 to a potential v _2, the said potential descent is given as an operation output or closed state output of the output circuit OTC to the terminal T ₇ of the microprocessor MPU, thereby it is possible to know that microprocessor MPU test result is normal. The microprocessor MPU transmits a signal indicating that the test result is normal to the transmission line CL via the signal transmission / reception circuit SRC with a self-address added as a test result signal, whereby the tester side It can be known that the sensor operates normally.

If, after the drive command from the terminal T ₂ is issued, if not receiving the operation output to the terminal T ₆ within a predetermined time period, the microprocessor MPU, the drive circuit DR _2, amplifier AMP, a fire decision circuit FDC, assumed that the switching circuit SW ₁ such abnormalities something like or a failure such as occurs, the transmission line via the signal transmitting and receiving circuit SRC from the terminal T ₅ by adding self addresses to the test result signal representative of the test results abnormal C- Send on L.

The setting of the constant of each element in the output circuit OTC for transmitting a short-circuit signal on the transmission line CL only when a fire occurs and not transmitting it during a test will be described with reference to FIG. FIG. 3 shows, in addition to the output circuit OTC similar to that shown in FIG. 1, a relay RL (impedance r, sensing current I) in a receiver connected via a transmission line CL. It is shown. The relay RL is operated by a short-circuit signal from the output circuit OTC, and the receiver can know the occurrence of a fire abnormality by a contact signal when the relay RL operates.

In FIG. 3, a voltage supplied between the transmission line C-L is E, the impedance of the relay RL is r, impressed current I, and the voltage effect in the operation display light-emitting element LED ₃ is V _{Suppose F.} Further, inputted to the terminal T ₇ of the microprocessor MPU of FIG. 1, the potential between the points P multi beauty Q is represented by v.

(1) Now, a voltage v between the points P and Q is obtained.

In a normal fire monitoring, when the PQ between potential v = v ₀ in the case of non-fire, when v ₀ = PQ between potential v = v ₁ when E _{fire, v 1 = [R 3 /} (R ₂ + R ₃ + r)] × (E−V _F ) + V _{F In the} test, if the potential between PQ and v = v ₂ when the test result is normal, v ₂ = [R ₃ / (R ₁ + R ₂ + R ₃₎ when + r)] and _{× (E-V F) +} V F between failures PQ in the case of test results abnormality potential v = v _3, the v ₃ = E. These potential v ₀ to v ₃ are represented in the column of "operation output from the output circuit" in Figure 2.

(2) Next, a transistor, that is, a switching circuit SW
_The current flowing through the relay RL of the receiver when ₁ is conducting is obtained.

When current i ₁ in the case of conventional fire monitoring when a fire occurs, i ₁ ≒ When _{(E-V F) / (} R 2 + R 3 + r) and current i ₂ in the case of the test machine test results normal, i ₂ ≒ (E−V _F ) / (R ₁ + R ₂ + R ₃ + r). This allows the relay RL to operate only when a fire occurs, and not to operate during a test.
It can be seen that the values of the resistors R ₁ , R ₂ , R _3, etc. must be set so that the RL sensing current I is i ₁ >I> i ₂ .

The operation of the present invention described above has several advantages.

First, according to the present invention, during operation tests, along with it can send and receive information to and from the tester is connected to the receiver side, the resistor R ₁ connected in series with the output circuit OTC, a switching circuit Works, but it does not send a short-circuit signal, that is, a fire signal, to the receiver side.Therefore, there is no need to perform recovery operations on the receiver, and there is no waiting time for recovery, so testing can be performed efficiently in a short time. it can.

Then, the time to test 500 sensors is 2 (seconds)
× 500 (pieces) = 1,000 (seconds). Therefore, the test can be performed in 1/5 time compared to the above-described conventional example.

In some cases, it may be desirable to perform a fire display operation test on the receiver side. In such a case,
For example the switch element SW ₂ is adapted to deliver to the detector to be tested a test command signal for remain closed, the switch element SW ₂ even when tested in this manner detector
Is kept closed, and a short-circuit signal as a fire abnormality signal is transmitted on the transmission line CL. The display operation test can be performed because the short-circuit signal causes the receiver to fire. in this case,
The correspondence between the activated sensor and the fire display window of the receiver is possible by storing the line number in the tester.

Further, as a method which does not transmits the operation output or shorted signal output circuit OTC at study on the transmission line C-L, without giving the output from the fire decision circuit FDC to the switching circuit SW _1, terminal T of the direct microprocessor MPU It is conceivable to switch at the time of the test as given in ₇ . However, it is not possible to test the output circuit OTC itself including a switching circuit SW ₁ in such a way. In this regard,
According to the embodiments described above, since so as to the closed state also operates the output circuit OTC by the generated fire alarm signal during the test, the test drive circuit DR ₂ and amplifier AMP, a fire decision circuit FDC In addition to the above, a test of the output circuit OTC is also possible.

[Effects of the Invention] As described above, according to the present invention, the output circuit of the sensor is closed during the operation test, but the short-circuit signal is not transmitted to the transmission line. There is an effect that a test can be performed accurately in a short time.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram showing a sensor according to an embodiment of the present invention, FIG. 2 is a timing chart for explaining the operation of FIG. 1, and FIG. FIG. 4 is a circuit diagram for explaining a setting method. In FIG, OTC output circuit, R ₁ is the resistance, SW ₁ is switching circuit, SE sensor unit, C-L is a transmission line.

Claims (1)

(57) [Claims] 1. A sensor including an output circuit for transmitting an abnormal signal through a transmission line by short-circuiting the transmission line when the abnormality is detected by closing the transmission line, wherein the sensor is transmitted through the transmission line. A resistor inserted in series in the output circuit in response to the incoming test command signal,
The resistor for preventing the transmission line from being short-circuited when the output circuit is closed, and the test for returning a test result signal in response to the test command signal via the transmission line. Determining means for determining whether or not the output circuit is in a closed state by an operation test performed in response to the command signal.