JP2834748B2 - Sensor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sensor such as a fire detector.

[Conventional Example] FIG. 3 shows a conventional example, in which a signal from a sensing unit 1 is amplified by an amplifier circuit 2 and a judgment circuit 3 judges whether or not to output an alarm, and judges that an alarm should be output. Output an alarm from the output circuit 4.

The criterion of the judgment circuit 3 is based on the reference value R of the reference circuit 5, and the reference value R can be adjusted by the sensitivity adjustment volume 6. Here, basically, the output characteristic from the sensing unit 1 is measured in advance, and the reference value is adjusted in accordance with the measured value.

[Case where the Invention is to be Solved] In the above-described conventional example, the variation in the sensing unit 1 and the amplifier circuit 2 is corrected in the manufacturing stage, and the value input to the determination circuit 3 is set within a certain range. It is necessary to provide an amplification rate adjustment volume 7.

Further, when the sensitivity is changed by the sensitivity adjustment volume 6, it is necessary to repeat the test to confirm whether the sensitivity is the desired one.

The present invention has been made in view of the above-described problems, and its purpose is to eliminate the adjustment at the manufacturing stage, to easily set the sensitivity by setting the situation in the setting state as the sensitivity as it is, and In order to provide a sensor which is easy to understand, a sensor capable of storing a reference value in a semiconductor memory, a sensor capable of electrically rewriting a reference value freely, and an alarm being transmitted by multiplex transmission. In addition, a sensor whose configuration has been simplified by also using a reference value storage circuit as a storage element for storing a set address for multiplex transmission, and furthermore, address setting and provision of a reference value storage trigger signal can be remotely performed. It is to provide a sensor that can be used.

Means for Solving the Problems The present invention relates to a reference storage trigger for storing a reference value in a sensor that outputs a warning by comparing a value of an input signal from a sensing unit with a preset reference value. The reference value storage circuit stores the maximum value or the minimum value of the input signal from the sensing unit within a fixed time from the input of the reference storage trigger signal as a reference value.

According to the second aspect of the present invention, the signal level from the sensing unit is set to A /
D-converted and stored as digital values,
The invention according to claim 3 uses an electrically erasable and rewritable storage element such as an EEPROM as a reference value storage circuit, and the invention according to claim 4 uses a sensor having a unique address for sending an alarm by multiplex transmission, The storage circuit is also used as a storage element for storing a unique address. The invention of claim 5 is characterized in that the address setting and the supply of the reference value storage trigger signal are performed using an optical wireless signal.

[Operation] In the present invention, the level of a signal input from sensing is set as a reference value as it is in an installed state, so that sensitivity setting can be easily and easily understood without being affected by circuit variations.

Also, by digitizing the reference value, the semiconductor memory element can be used as a reference value storage circuit, and by using an EEPROM as the reference value storage circuit, the reference value can be freely rewritten electrically and power supply can be performed. Even when stopped, the stored reference value can be saved. Also, by using multiplex transmission, an alarm output can be transmitted to a receiver at a remote place. In addition, since a storage element such as an EEPROM is also used as a storage element of a unique address of multiplex transmission, it is advantageous in terms of cost, and Further, by using the optical wireless signal, the address setting and the provision of the reference value storage trigger signal can be performed from a position remote from the sensor.

EXAMPLES The present invention will be described below with reference to examples.

FIG. 1 shows a circuit configuration of an embodiment adopting the present invention. In this embodiment, a signal inputted from a sensing section 1 and amplified by an amplifier circuit 2 is inputted to a judgment circuit 3 and at the same time, a reference value storage circuit is provided. 8 is input.

Here, in a state where the sensor is set, a state in which an alarm is desired to be output is set. In this state, when a reference value storage trigger signal TR is externally applied, the amplifier circuit 2 within a predetermined time from the input of the storage trigger signal TR. The reference value storage circuit 8 stores the maximum value or the minimum value of the input signal as the reference value R.

Thereafter, the judgment circuit 3 judges whether or not to output an alarm by comparing the reference value R stored in the reference value storage circuit 8 with the output signal level from the amplifier circuit 2.

FIG. 3 shows an example of the reference value storage circuit 8, in which a signal from the amplifier circuit 2 is input to the A / D conversion circuit 9 through the gate circuit 12 and the peak hold circuit 13. When the reference value storage trigger signal TR shown in FIG. 5A is input, the peak hold circuit 13 is reset at the rise of the reference value storage trigger signal TR and the one-shot circuit 14 is triggered at the fall. FIG. 4 (b) shows the gate signal output from the triggered one-shot circuit 14, and FIG. 4 (d) shows the output of the peak hold circuit 13. Now, the gate circuit 12 is operated by the gate signal.
Open during the output period of the gate signal, while the gate circuit 12 is open, the signal from the amplifier circuit 2 is input to the peak hold circuit 13, and the maximum value of the input signal is held by the peak hold circuit 13. A / D conversion is performed by the A / D conversion circuit 9. The A / D-converted digital value is latched by the latch circuit 10 from the fall of the gate signal of the one-shot circuit 14, and thereafter, the peak value while the gate circuit 12 is open is shown in FIG. As shown, the reference value R
Is output to the decision circuit 3.

Here, a description will be given of a case where the present invention is applied to a glass breakage sensor. After attaching the sensor, a reference value storage trigger signal TR is input, and the glass is “don” within a predetermined time (for example, 3 seconds).
When hit, the magnitude of this vibration is input as an input signal from the sensing unit 1 and the maximum value of the signal is stored in the latch circuit 10 as the reference value R. Therefore, the sensitivity can be set according to the actual feeling by tapping the glass lightly to improve the sensitivity, and strongly tapping the glass to reduce the impression.

The sensors are not limited to the glass breakage sensors described above. For example, photoelectric smoke detectors A, ion smoke detectors B, and constant temperature detectors as shown in FIGS. 5, 6, and 7, respectively. It may be used for various fire detectors such as C and other sensors such as gas sensors.

Here, for example, when setting the sensitivity of the photoelectric or ionic smoke detector A or B as shown in FIG. 5 or FIG. 6, the photoelectric smoke detector is placed in smoke of a predetermined concentration. Then, when the reference value storage trigger signal TR is given, the smoke density is stored as the reference value R, and the sensitivity of the smoke density can be set. Here, the sensitivity can be freely set by placing the filter in a thin smoke when the sensitivity is desired to be improved, and in a dense smoke when the sensitivity is to be lowered. A method of putting the sensor in the smoke before giving the reference value storage trigger signal TR and a method of giving the reference value storage trigger signal TR first and then putting it in the smoke can be considered. In other words, these methods are possible by changing the time from when the reference value storage trigger signal TR is given to when the reference value R is set. In the former method, a few seconds, and in the latter method, the smoke sufficiently enters the sensor. It is necessary to make it a little longer than it is considered.

In the constant temperature sensor C shown in FIG. 7, if the sensor is put in an atmosphere of a predetermined temperature and a reference value storage trigger signal TR is given, the temperature is stored as a reference value R, and the temperature is detected. Can be set to Here, the sensitivity can be freely set by increasing the sensitivity to a lower temperature when the sensitivity is desired to be improved, and by setting the temperature to a higher temperature when the sensitivity is deteriorated.
Also, a method of putting the sensor in a predetermined atmosphere before giving the reference value storage trigger signal TR and a method of giving the reference value storage trigger signal TR first and then putting it in the predetermined atmosphere are considered. Can be In other words, these methods can be performed by changing the time from when the reference value storage trigger signal TR is given to when the reference value R is set. In the former method, the sensing unit 1 is sufficiently exposed to the atmosphere for a few seconds. It is necessary to make it a little longer than the time it is considered to be temperature.

FIG. 8 shows a circuit configuration of another embodiment using the present invention. The sensor of this embodiment is a sensor used in a system for returning monitoring information to a receiver using multiplex transmission. A multiplex transmission / reception circuit 15 is provided for transmitting and receiving data using multiplex transmission signals between them, and the judgment information in the judgment circuit 3 is returned to the receiver by multiplex transmission. Reference value storage trigger signal of reference value storage circuit 9
TR is externally given as an optical wireless signal. When the optical wireless receiving circuit 16 receives the reference value storage trigger signal TR, it converts it into an electric signal and gives it once to the determination circuit 3. . The determination circuit 3 performs signal processing and control processing inside the sensor using a microcomputer or the like. For example, the determination circuit 3 uses the reference value storage trigger signal TR as a write command to the reference value storage circuit 9 and outputs the reference value storage trigger signal TR. In addition to the output to the reference circuit 9, the determination circuit 3 performs processing such as an instruction to read the reference value R from the reference value storage circuit 9.

Here, as the storage element of the reference value storage circuit 9, a semiconductor storage element such as an EEPROM, which is electrically erasable and rewritable and stores stored data even when power supply is stopped, is used.

FIG. 9 shows a flow chart of the reference value R changing process of this embodiment. The judgment circuit 3 judges whether or not the reference value storage trigger signal TR is received, and the reference value storage trigger signal TR is received. Then, first, a command to clear the currently stored contents is given to the reference value storage circuit 9 to clear the stored contents. After this clearing, the timer function is operated, and the signal from the amplifier circuit 2 is input. The level of the input signal is updated so that the level of this signal becomes the largest value during a certain period in which the timer operation of the timer function ends, and the signal level at that time is set as a reference value R at the same time when the timer operation ends. This is written into the value storage circuit 9.

As a multiplex transmission system in which the embodiment of FIG. 8 is used, there is a system as shown in FIG. The system comprises a central controller 17 as a receiver, a plurality of monitoring terminal 18 for monitoring the switches S ₁ to S ₄ unique address is set,
The control terminal 19 for controlling the loads L _{1 to} L ₄ , the wireless relay terminal 20, the external interface terminal 21, and the pattern setting terminal 22 are connected by a 23-wire signal line 1, As shown in FIG. 11A, the transmission signal Vs transmitted from the central controller 17 to the signal line 1 includes a start pulse signal ST indicating the start of signal transmission, a mode data signal MD indicating a signal mode, and a terminal 18. Address data signal AD for transmitting 8-bit address data, loads L _{1 to} L ₄
(± 24V) consisting of a control data signal CD for transmitting control data, a checksum data signal CS, and a return wait signal WT for setting a return period from the terminals 18 to 22
, And the data is transmitted by pulse width modulation. In each terminal 18-22,
When the address data of the transmission signal Vs received via the signal line l matches the own unique address data, the control data of the transmission signal Vs is taken in, and the transmission signal Vs
The monitor data signal is returned as a current mode signal (a signal transmitted by short-circuiting the signal line 1 via a suitable low impedance) in synchronization with the return standby signal WT. Also, the central control unit 17 has a mode data signal MD.
A dummy signal transmitting means for constantly transmitting a dummy transmission signal in a dummy mode, and any one of the monitoring terminal 18 or the wireless relay terminal 20 and the external interface terminal 2
1. When an interrupt signal Vi as shown in FIG. 11 (b) returned from the pattern setting terminal 22 is received,
Detect the interrupt generating terminal 18, 20 to 22 and detect the terminal 18, 20
And an interrupt processing means for accessing .about.22 to return monitoring data. In the central control unit 17,
Also as described above, based on the monitoring data returned from the monitoring terminal 18 or the wireless relay terminal 20, the external interface terminal 21, and the pattern establishment terminal 22 to the central control device 17, the corresponding loads L ₁ to as well as generates control data to be transmitted to the control terminal 19 for controlling the L _4, the control data to two o'clock with the control terminal 19 division multiplexing transmission via a signal line l load L ₁ ~L ₄ Control. The wireless relay terminal 20 includes an optical wireless transmitter Y, an optical wireless receiver X, and a wireless signal line L.
A data relay of an optical wireless system comprising an optical signal transmitted from an optical wireless transmitter Y, received by an optical wireless receiver X, and receiving the received data via a wireless signal line L. Upon receipt, this data is transferred to the central control unit 17. The external interface terminal 21 is a terminal that performs data transmission with the external control device 21a, and the pattern setting terminal 22 sends pattern control data input from the data input unit 22a to the central control device 17. It is a terminal that transfers. The monitoring terminal 18 and the control terminal 19 provided in the distribution board 23 or the relay control panel 23a have a distribution board agreement size, and the control output thereof is used to control the remote control relay for load control. (Latching relay that can be turned on and off by a hand switch) 24 is controlled. Here, the sensor used in the present invention is an external interface terminal 21 and an external control device 21a.
, And the external control device 21a corresponds to the sensing unit. The reference signal trigger signal TR may be provided by using the wireless transmitter Y of the wireless system in the system, or another wireless transmitter may be used. In the sensor of FIG. 8, the EEPROM constituting the reference value storage circuit 8 is also used as a storage element for storing a unique address, and the address is set by an optical wireless signal in the same manner as the provision of the reference value storage trigger signal. ing. Of course, the address setting and the reference value storage may be stored in different storage elements.

According to the first aspect of the present invention, as described above, the level of the signal input from the sensing unit can be set as a reference value as it is in the installation state, and thus the sensitivity setting is generated in manufacturing. This makes it easy and easy to understand without being affected by variations in the manufacturing process, and does not require adjustment in the manufacturing process.

According to the invention of claim 2, the semiconductor storage element can be used as a reference value storage circuit by digitizing the reference value. Further, the invention of claim 3 uses an EEPROM as the reference value storage circuit to achieve electrical The reference value can be freely rewritten, and the stored reference value can be saved even when the power supply is stopped. According to the fourth aspect of the present invention, an alarm output can be sent to a receiver at a remote place by using multiplex transmission, and the EEPROM is also used as a storage element of a unique address of multiplex transmission, which is advantageous in cost. According to the fifth aspect of the present invention, the address setting and the provision of the reference value storage trigger signal can be performed from a position remote from the sensor by using the optical wireless signal.

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram of one embodiment of the present invention, FIG. 2 is a circuit configuration diagram of a conventional example, and FIGS. 3 and 4 are circuit configuration diagrams showing an example of a reference value storage circuit used in the first embodiment. FIG. 5 is a side view of the photoelectric smoke detector used in the embodiment, FIG. 6 is a perspective view of the ion smoke sensor used in the embodiment, and FIG. 7 is a perspective view of a constant temperature heat sensor used in the embodiment. FIG. 8, FIG. 8 is a circuit configuration diagram of a sensor using the method of another embodiment of the present invention, FIG. 9 is a flowchart for explaining the operation of the same, FIG. 10 is a system configuration diagram of a multiplex transmission system using the same, FIG. 11 is an explanatory diagram of a signal format using a multiplex transmission system using the same as above, and FIG.
The figure is the actual wiring diagram of the multiplex transmission system using the above. R is a reference value, TR is a reference value storage trigger signal, 1 is a sensing unit, 2 is an amplifier circuit, 3 is a judgment circuit, 4 is an output circuit,
8 is a reference value storage circuit, 9 is an A / D conversion circuit, 10 is a latch circuit, 11 is a D / A conversion circuit, 12 is a gate circuit, 13 is a peak hold circuit, 14 is a one-shot circuit, and 15 is multiplex transmission / reception. The circuit 16 is an optical wireless receiving circuit.

Claims (5)

(57) [Claims] 1. A sensor for comparing a value of an input signal from a sensing unit with a preset reference value and outputting an alarm, wherein a reference storage trigger signal for storing the reference value is used for the reference storage trigger. A sensor characterized in that a maximum value or a minimum value of an input signal from a sensing unit within a predetermined time from a signal input is stored in a reference value storage circuit as a reference value. 2. The sensor according to claim 1, wherein a signal level from the sensing unit is A / D converted and stored as a digital value. 3. The sensor according to claim 1, wherein an electrically erasable and rewritable storage element such as an EEPROM is used as the reference value storage circuit. 4. The sensor according to claim 3, wherein a sensor having a unique address for outputting an alarm by multiplex transmission is used, and the reference value storage circuit is also used as a storage element for storing the unique address. 5. The sensor according to claim 4, wherein the address setting and the provision of the reference value storage trigger signal are performed using an optical wireless signal.