JP2006085430A - Alarm device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alarm device which is equipped with a sensor module part constituted so as to be freely attachable/detachable to/from the main body part for easily replacing the sensor module part with another one, and whose cost can be reduced. <P>SOLUTION: This alarm device is provided with the sensor module part 2 configured so as to be attachable/detachable to/from a main body part 1, and the sensor module part 2 is provided with a sensor part 3 which converts the characteristic change of a sensor element 11 for developing detection capability according as the characteristics of a predetermined detection object changes into an electric signal, and outputs it, and a sensitivity adjusting element storing means 4 for storing the sensitivity adjusting element of the sensor part 3. The main body part is provided with a driving control part 5 for controlling driving of the sensor part 3, a deciding part 6 for deciding whether or not an alarm has to be outputted on the basis of a sensor output to be outputted from the sensor part 3, an alarm outputting part 7 for outputting the alarm and a power source part 8 for supplying predetermined electric power to each of the main body part 1 and the sensor module part 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an alarm device including a sensor module part that is detachable from a main body part.

  As an alarm device including a sensor module part that is detachable from the main body part, there are those disclosed in Patent Document 1 and Patent Document 2 below.

  The alarm device described in Patent Document 1 is a gas / fire integrated alarm device, and includes a fire detection unit and a gas sensor unit, and the gas sensor unit is configured separately from the fire detection unit. It is detachable and corresponds to the sensor module section. In the alarm device described in Patent Document 1, the gas sensor unit is configured to be detachable from the fire detection unit corresponding to the main body unit. Can be used. Here, the gas sensor unit includes a detection circuit, an adjustment circuit, a determination circuit, and a voltage control circuit in addition to the gas sensor.

The alarm device described in Patent Literature 2 is an alarm device including a sensor unit and an alarm device body, and the sensor unit is detachable from the alarm device body, and corresponds to a sensor module unit. A sensor unit of an alarm device described in Patent Document 2 includes a conversion circuit that converts a change in electrical properties of the sensor into an electrical signal, and an alarm that should issue an alarm in which the electrical signal level obtained from the conversion circuit is stored in advance. Compared with the level, alarm signal generating means for generating an alarm signal, sensor unit output means for outputting the alarm signal generated by the alarm signal generating means to the alarm device body, and the sensor is sensitive to a reference detection target A configuration comprising alarm level setting means for setting an electric signal level obtained from the conversion circuit to the alarm level in an alarm level setting state, and the alarm signal generating means operates according to the alarm level set by the alarm level setting means It has become.
Japanese Patent No. 344527 Japanese Patent Laid-Open No. 2002-74557

  However, in the case of the alarm device disclosed in Patent Document 1, the sensor module unit (gas sensor unit) includes a detection circuit in addition to a sensor element that exhibits detectability by changing properties with respect to a predetermined detection target. In addition, an adjustment circuit, a determination circuit, and a voltage control circuit are provided, and when the sensor module part is replaced, circuit parts other than the sensor element having a short life are also replaced at the same time.

  Further, in the case of the alarm device disclosed in Patent Document 2, the sensor module unit (sensor unit) includes a conversion circuit, an alarm, in addition to the sensor element, as in the alarm device disclosed in Patent Document 1. A signal generation unit, a sensor unit output unit, and an alarm level setting unit are provided, and when replacing the sensor module unit, circuit portions other than the sensor elements having a short lifetime are also replaced at the same time.

  As described above, the reason why many circuits other than the sensor element are provided in the sensor module section is that each sensor element has a variation in individual characteristics, and the sensor output in a state where the detection target is detected also fluctuates. This is because it is necessary to adjust the determination circuit and the alarm signal generation means on the sensor output side or the sensor output receiving side in accordance with the variation in the sensor element characteristics.

  In the case of the alarm device disclosed in Patent Document 2, the alarm signal generating means, the sensor section output means, and the alarm level setting means are realized by a single microprocessor, so that only a part of the circuits is transferred to the main body section. In addition, when all these circuits are transferred to the main body, adjustment of the circuit of the main body in accordance with the characteristic variation of the sensor element is required every time the sensor module is replaced.

  As described above, in the case of an alarm device including a sensor module part that is detachable from the conventional main body part, the main function of the alarm device is provided in the sensor module part, and the circuit scale of the sensor module part is large. It was difficult to reduce the cost of the sensor module part due to the reduction.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to eliminate the above-described problems and to include a sensor module part that is detachable from the main body part, so that the sensor module part can be easily replaced. Another object of the present invention is to provide an alarm device capable of reducing the cost.

  In order to achieve this object, an alarm device according to the present invention is an alarm device comprising a sensor module part detachably attached to a main body part, and the sensor module part has a property with respect to a predetermined detection target. A sensor unit that converts the property change of the sensor element that exhibits detection ability by changing it into an electrical signal and outputs it, and a sensitivity adjustment element storage unit for storing the sensitivity adjustment element of the sensor unit, The main body unit is a drive control unit that controls driving of the sensor unit, a determination unit that determines whether or not to output an alarm based on a sensor output output from the sensor unit, an alarm output unit that outputs the alarm, A first feature is that a power supply unit that supplies predetermined power to each of the main body unit and the sensor module unit is provided.

  According to the alarm device of the first feature, the sensor module unit includes the sensor unit and the sensitivity adjustment element storage unit, and the drive control unit and the determination unit that are conventionally provided on the sensor module unit side are provided on the main body side. Therefore, the number of circuits constituting the sensor module unit can be reduced, and the cost of the sensor module unit can be reduced. As a result, the cost can be reduced throughout the life cycle of the alarm device. In addition, since the sensor module unit is provided with the sensitivity adjustment element storage unit, information necessary for adjusting the characteristic variation of the sensor element is provided from the sensor module unit to the main body unit. Whether or not to output an alarm based on the comparison result of the sensitivity adjustment element stored in the sensor and the sensor output output from the sensor unit. There is no need to adjust the body to fit the difference.

  The alarm device of the first feature further has a second feature that a semiconductor gas sensor is included as the sensor element included in the sensor module unit.

  According to the alarm device of the second feature, it is possible to provide an alarm device that emits an alarm in response to a predetermined detection target gas, and by using a semiconductor gas sensor as a sensor element, the configuration of the sensor unit of the sensor module unit The circuit configuration for converting the property change of the sensor element into an electrical signal can be simplified.

  The alarm device according to the second feature is further characterized in that the semiconductor gas sensor can detect at least one of combustible gas and carbon monoxide.

  According to the alarm device of the third feature, an alarm device that detects a gas leak such as city gas by detecting the flammable gas such as methane and issues an alarm, and an alarm device that detects carbon gas monoxide by the detectability of carbon monoxide. It is possible to provide an alarm device that issues a warning by detecting complete combustion, or a multi-function alarm device having both functions.

  In the alarm device of the third feature, the sensor unit further includes a semiconductor gas sensor capable of detecting both flammable gas and carbon monoxide as the sensor element, and a detection target by a control signal from the drive control unit. A fourth feature is that a load resistance circuit capable of selecting a resistance value corresponding to the gas type is provided.

  According to the alarm device of the fourth feature, the sensor unit is caused to switch between detecting ability of flammable gas such as methane and detecting ability of carbon monoxide by a control signal from the drive control part of the main body part. Therefore, it is possible to selectively realize either an alarm device that detects a gas leak such as city gas and issues an alarm and an alarm device that detects an incomplete combustion such as city gas and issues an alarm. Furthermore, by performing switching control of the detection capability of flammable gas such as methane and the detection capability of carbon monoxide in a time-sharing manner for the sensor unit, two detection capabilities are demonstrated using one sensor module unit. It is possible to realize an alarm device that issues an alarm by separately detecting gas leaks such as city gas and incomplete combustion.

  The alarm device according to any one of the first to fourth features has a fifth feature that the sensor module unit further includes a variable resistance element as the sensitivity adjustment element storage unit.

  According to the alarm device of the fifth feature, for example, the load resistance provided in the sensor unit is configured by a variable resistance element, and the resistance value of the variable resistance element is adjusted, thereby varying the characteristics of the sensor element. Can be adjusted on the sensor module side. Alternatively, by adjusting the resistance value of the variable resistance element, the sensitivity adjustment element or a comparison value of the sensor output output from the sensitivity adjustment element and the sensor unit can be output to the main body unit as analog data.

  The alarm device according to any one of the first to fifth characteristics is further characterized in that the sensor module unit includes a nonvolatile semiconductor memory as the sensitivity adjustment element storage unit.

  According to the alarm device of the sixth feature, the sensitivity adjustment element can be stored and processed as digital data. Therefore, when the drive control unit and the determination unit on the main body side are constituted by digital signal processing means such as a microprocessor. It is preferable that consistency is maintained in data transmission and reception. In addition, since the nonvolatile semiconductor memory has a large information capacity that can be stored as compared with analog storage means such as a variable resistance element, a variety of sensitivity adjustment elements can be stored, and sensors other than the sensitivity adjustment elements can be stored. Information useful for driving control of the unit can also be stored, which contributes to improving the quality of the alarm device.

  In the alarm device according to the sixth aspect, the determination unit further reads sensitivity adjustment element data related to the sensitivity adjustment element stored in the nonvolatile semiconductor memory, and outputs the sensor adjustment output based on the sensitivity adjustment element data. Setting a determination criterion is a seventh feature.

  According to the alarm device having the seventh feature, the determination unit can set the determination criterion according to the fluctuation of the output value of the sensor output due to the characteristic variation of the sensor element based on the sensitivity adjustment element data. There is no need to adjust the main body so as to adapt to individual differences in the sensor module when replacing the sensor module.

  The alarm device according to the sixth or seventh feature is further characterized in that the nonvolatile semiconductor memory is capable of storing a control parameter for the drive control unit to perform drive control on the sensor unit. And

  In the alarm device according to the eighth feature, the drive control unit further reads out the control parameter stored in the nonvolatile semiconductor memory and performs drive control on the sensor unit based on the read-out control parameter. Is the ninth feature.

  According to the alarm device of the eighth or ninth feature, the drive control unit can read the control parameter stored in the nonvolatile semiconductor memory, and can perform drive control on the sensor unit based on the read control parameter. Even if the sensor module is replaced with another sensor module having a different drive control, the sensor module having a different drive control can be used without any adjustment on the main body side. As a result, a variety of alarm devices can be manufactured at a low cost simply by replacing the sensor module part with the smallest circuit scale using the same main body part.

  The alarm device according to the eighth or ninth feature further has as a tenth feature that the control parameter includes a parameter defining a voltage waveform to be applied to a predetermined node of the sensor unit.

  According to the alarm device of the tenth feature, the voltage value of the voltage waveform applied to a predetermined node of the sensor unit, the application time, and the like can be changed based on the control parameter, so that it is suitable for the sensor element and detection target of the sensor unit. The sensor unit can be driven by the voltage waveform thus obtained.

  In the eleventh feature, the alarm device according to the eighth or ninth feature further includes, as the control parameter, a parameter that defines a duty ratio when a voltage is applied to a predetermined node of the sensor unit by PWM control. To do.

  According to the alarm device of the eleventh feature, since the duty ratio of the voltage by the PWM control applied to the predetermined node of the sensor unit can be changed based on the control parameter, the duty that is suitable for the sensor element and detection target of the sensor unit The sensor unit can be driven by a voltage by PWM control of the ratio.

  The alarm device according to any one of the eighth to eleventh features further includes a parameter defining a detection time point of the sensor output output from the sensor unit as the control parameter. .

  According to the alarm device of the twelfth feature, since the determination unit of the main body unit detects the sensor output at the time of detection of the sensor output suitable for the sensor element and the detection target included in the sensor unit, Applicable and appropriate alarm output judgment can be performed.

  In the alarm device according to any one of the first to twelfth characteristics, the sensor module unit further includes a voltage adjusting unit that adjusts a voltage value applied to a predetermined node of the sensor unit. And

  According to the alarm device of the thirteenth feature, when the voltage value applied from the main body unit to the sensor unit of the sensor module unit is unstable, or when it is difficult to accurately apply an appropriate voltage value, the voltage adjusting means Thus, a stable voltage or an appropriate voltage can be applied to the sensor unit.

  The alarm device according to any one of the first to thirteenth features further includes contact resistance detection means for detecting a resistance component parasitic on a contact between the main body portion and the sensor module portion. Features.

  According to the alarm device of the fourteenth feature, a voltage drop occurs in the voltage supplied from the main unit to the sensor module unit due to a resistance component parasitic on the contact point between the main unit and the sensor module unit. The case where supply cannot be performed can be detected in advance. By detecting the abnormality of the parasitic resistance component, it is possible to prevent the alarm device from being used as a normal operation state with the contact abnormality between the main body part and the sensor module part and failing to fully perform the original function. In addition, if the voltage drop due to the resistance component can be separately corrected, voltage supply with an appropriate voltage value can be performed from the main body to the sensor module.

  The alarm device according to any one of the first to fourteenth features further has a fifteenth feature that the sensor module unit can be equipped with two or more sensor units having different detection targets.

  According to the alarm device having the fifteenth feature, since the sensor module unit can be equipped with two or more sensor units, it is possible to provide an alarm device capable of selecting various detection targets depending on the combination of the equipped sensor units. Become. Further, since the type and number of detection targets can be adjusted depending on the application, for example, the detection target can be changed or added even after the alarm device is installed at a predetermined use location.

  The alarm device according to any one of the first to fifteenth features further includes at least one of information indicating a type of the sensor element and individual identification information of the sensor element in the nonvolatile semiconductor memory. The memorizing is the sixteenth feature.

  According to the alarm device of the sixteenth feature, information related to sensor elements such as detectability of the sensor module unit can be grasped by electrically reading information stored in the nonvolatile semiconductor memory from the outside.

  The sensor module according to the present invention is a sensor module that is detachable from the main body of the alarm device having any one of the first to fifteenth features, and that is detected by changing the properties of a predetermined detection target. A sensor unit that converts the property change of the sensor element that exhibits the performance into an electrical signal and outputs it, and a sensitivity adjustment element storage unit for storing the sensitivity adjustment element of the sensor unit, and the sensor unit includes: Drive-controlled by a control signal from the main body, and configured to output the electrical signal to the main body, and the sensitivity adjustment element storage means outputs the stored data of the sensitivity adjustment element to the main body It is configured to be possible.

  According to the sensor module having the above characteristics, the sensor module includes a sensor unit and a sensitivity adjustment element storage unit, and a drive control unit and a determination unit that are conventionally provided on the sensor module side are provided on the main body side. The number of circuits constituting the sensor module can be reduced, and the cost of the sensor module can be reduced. As a result, the cost of the alarm device including the sensor module can be reduced throughout the life cycle. In addition, by providing the sensitivity adjustment element storage means in the sensor module, information necessary for adjusting the characteristic variation of the sensor element is provided from the sensor module to the main body section. Therefore, the sensitivity adjustment element storage means is provided on the main body side. It is possible to determine whether or not to output an alarm based on the sensitivity adjustment element stored in the sensor and the sensor output output from the sensor unit, so that the sensor module can be adapted to individual differences when replacing the sensor module. There is no need to adjust the main body.

  A sensor module operation method according to the present invention is a sensor module operation method that is detachable from a main body of an alarm device, wherein the sensor module is driven and controlled by a control signal from the main body, Storing at least a sensor unit that converts the property change of the sensor element that exhibits detectability by changing the property with respect to the detection target and outputs the electrical signal to the main body unit, and a sensitivity adjustment element of the sensor unit; , Comprising sensitivity adjustment element storage means configured to output the stored data of the sensitivity adjustment element to the main body, and reading connection confirmation data from the sensor module, A first feature is that when the data can be read, the sensitivity adjustment element data is read from the sensitivity adjustment element storage means.

  According to the operation method of the sensor module of the first feature, after the sensor module having the sensor unit and the sensitivity adjustment element storage means is checked for the connection state with the sensor module, the sensitivity adjustment element storage of the sensor module is performed. Since the data of the sensitivity adjustment element stored in the means is read out, the data of the sensitivity adjustment element is reliably provided as information necessary for adjustment with respect to the characteristic variation of the sensor element in the connection state of the sensor module. It is possible to determine whether or not to output an alarm based on the sensor output output from. Therefore, since the alarm output determination suitable for the connected sensor module is made, it is not necessary to adjust the main body so as to adapt to the individual difference of the sensor module when the sensor module is replaced.

  A sensor module operation method according to the present invention is a sensor module operation method that is detachable from a main body of an alarm device, wherein the sensor module is driven and controlled by a control signal from the main body, A sensor unit that converts the property change of the sensor element that exhibits detectability by changing the property with respect to the detection target, and outputs it to the main body unit, a sensitivity adjustment element of the sensor unit, and the sensor unit A control parameter for performing drive control with respect to the sensor, and the sensitivity adjustment element storage means configured to output the stored sensitivity adjustment element and data of the control parameter to the main body, A step of reading data of the control parameter from the sensitivity adjustment element storage means; and a driver for the sensor unit based on the read control parameter. And performing control, by having the second feature.

  According to the operation method of the sensor module of the second feature, the sensor module including the sensor unit and the sensitivity adjustment element storage unit is configured to perform drive control on the sensor unit stored in the sensitivity adjustment element storage unit. Since the control parameters are read and the drive control for the sensor unit is performed based on the control parameters, even if the drive control of the sensor module is different for each sensor module, the control method suitable for the sensor module to be driven is used. Drive control is possible. Accordingly, when the alarm device is formed by integrating the sensor module and the main body of the alarm device, the sensor module is driven from the main body, or the sensor module is driven from the test device during the shipping test of the sensor module. However, it can be executed in accordance with the drive control method of the sensor module.

  An embodiment of an alarm device according to the present invention (hereinafter referred to as “the present device” as appropriate) will be described with reference to the drawings.

<First Embodiment>
FIG. 1 shows a circuit configuration of the device of the present invention. As shown in FIG. 1, the device of the present invention includes a main body 1 and a sensor module 2 that is detachable from the main body 1. The sensor module unit 2 outputs, as an electrical signal, the detection state of the detection target gas by a sensor element composed of a semiconductor gas sensor that can selectively detect two types of detection target gases, methane and carbon monoxide, by driving control of the heater. And a sensitivity adjustment element storage means 4 for storing a sensitivity adjustment element of the sensor section 3 and a control parameter for controlling driving of the sensor section 3. On the other hand, the main body unit 1 includes a drive control unit 5 that controls driving of the sensor unit 3, a determination unit 6 that determines whether to output an alarm based on a sensor output that is output from the sensor unit 3, and a determination unit 6. An alarm output unit 7 that outputs an alarm based on the alarm output determination, a power supply unit 8 that supplies predetermined power to each part of the main body unit 1 and the sensor module unit 2, and temperature correction in the alarm output determination process of the determination unit 6 For this purpose, a temperature sensor 9 such as a thermistor for detecting the temperature is provided.

  As shown in FIG. 2, the sensor unit 3 includes two different load resistors R1 and R2 between the sensor output terminal 12 of the sensor element 11 formed of a semiconductor gas sensor formed integrally with the heater 10 and the power supply voltage Vcc. Are provided in parallel. However, the load resistor R2 forms a series circuit with the switching transistor T and is provided between the sensor output terminal 12 and the power supply voltage Vcc. With this configuration, the amplitude of the sensor output for detection / non-detection of the detection target gas due to the difference in temperature control of the heater 10 when the detection target gas is methane and carbon monoxide by the on / off operation of the switching transistor T. It becomes possible to adjust appropriately. The load resistors R1 and R2 are fixed resistors in this embodiment, and their resistance values are, for example, 100 kΩ and 10 kΩ, for example. It should be noted that the sensor output appearing on the sensor output terminal 12 is the electric power of the sensor element 11 between the sensor output terminal 12 and the ground terminal side of the heater 10 depending on the presence or absence of carbon monoxide when the temperature control of the heater 10 is around 100 ° C. The resistance changes when the resistance changes remarkably. Further, when the temperature control of the heater 10 is 400 to 500 ° C., the resistance changes depending on the presence or absence of methane. As will be described later, the switching transistor T is ON / OFF controlled by a control signal from the drive control unit 5 of the main body unit 1 in accordance with the drive control timing of the heater 10.

  In the present embodiment, the temperature control of the heater 10 of the sensor element 11 is performed by PWM (pulse width modulation) control of a constant voltage (for example, 3.3 V), that is, the voltage pulse applied to the heater 10 is turned on (voltage application). By controlling the time ratio (duty ratio) between the (state) and off (voltage non-applied state), the effective applied voltage is adjusted and the temperature applied to the sensor element 11 is controlled. An example of an applied voltage waveform by PWM control of the heater 10 is shown in FIG.

  The sensitivity adjustment element storage means 4 is composed of a nonvolatile semiconductor memory such as an EEPROM which can electrically erase and write data. The sensitivity adjustment element stored in the sensitivity adjustment element storage unit 4 is, for example, a sensor output voltage value corresponding to the resistance value of the sensor element 11 at a predetermined detection specified concentration. Here, the resistance value at a predetermined detection specified concentration varies depending on individual differences in resistance characteristics with respect to the concentration of each detection target gas of the sensor element 11. Hereinafter, the voltage value of the sensor output at the predetermined detection specified concentration is referred to as a detection threshold voltage. Note that the prescribed detection concentration is plural when the detection level is set stepwise for each detection target gas, and in that case, the detection threshold voltage is plural.

  Further, as control parameters stored in the sensitivity adjustment element storage means 4, detection start of voltage pulse application start timing, end timing, its duty ratio, and sensor output by PWM control for methane detection as shown in FIG. Timing, voltage pulse application start timing by PWM control for purge processing before carbon monoxide detection, end timing, and its duty ratio, voltage pulse application start timing by PWM control for carbon monoxide detection, end timing, The duty ratio and sensor output detection timing are assumed.

  The drive control unit 5 of the main body unit 1 controls a sensor drive unit 5a that drives a voltage pulse applied to the heater 10 of the sensor element 11, a drive timing of the voltage pulse that is driven by the sensor drive unit 5a, and a duty ratio of the voltage pulse. And a pulse controller 5b. The pulse control unit 5b of the drive control unit 5 is configured in the microprocessor 13 provided in the main body unit 1, reads the control parameters stored in the sensitivity adjustment element storage unit 4 from the sensitivity adjustment element storage unit 4, and The drive timing and duty ratio of the corresponding voltage pulse are controlled by the start timing, end timing and duty ratio of each voltage pulse application of the control parameter, and the sensor drive unit 5a controls the heater 10 in the sensor unit 3 according to the control. Then, it is driven so as to have a predetermined temperature control pattern. The microprocessor 13 includes a microcomputer incorporating a ROM and RAM for storing programs, and it does not matter whether the ROM or RAM is incorporated or provided externally.

  The determination unit 6 outputs each sensor output at the detection timing of the sensor output for methane detection and the detection timing of the sensor output for carbon monoxide detection among the control parameters stored in the sensitivity adjustment element storage unit 4. The detected sensor output read and the detection threshold voltage for detection of methane of the sensitivity adjustment element stored in the sensitivity adjustment element storage means 4 or the detection threshold after temperature correction of the detection threshold voltage for detection of carbon monoxide Compared with the voltage, it is determined whether the concentration of methane or carbon monoxide is higher than the specified detection concentration. If the concentration of methane is higher than the detection specified concentration of methane, it is determined that a gas leak has occurred. A gas leak determination signal is output, and when the concentration of carbon monoxide is equal to or higher than the detection specified concentration, it is determined that the combustion state is incomplete and an incomplete combustion determination signal is output.

  The temperature correction of each detection threshold voltage for methane detection and carbon monoxide detection is obtained by multiplying the difference between the temperature at the time of setting each detection threshold voltage and the temperature detected by the temperature sensor 9 by a preset correction coefficient. This correction voltage value is added to or multiplied by each detection threshold voltage. In addition, there is a method of using a function, or deriving a correction coefficient from a table showing the relationship between temperature data and a set value, and adding or multiplying each detection threshold voltage.

  The determination unit 6 is configured in a microprocessor 13 provided in the main body unit 1, and a sensor output (analog value) is input from a predetermined analog port of the microprocessor 13, and an A / D conversion unit in the microprocessor 13. Sampled and digitized. The sampling timing at this time is defined by the detection timing of the sensor output of each detection target gas in the control parameters. Further, the temperature detection output (analog value) of the temperature sensor 9 is also input from a predetermined analog port of the microprocessor 13, sampled by the A / D converter in the microprocessor 13, and digitized.

  The alarm output unit 7 includes an optical alarm output unit 14 including an LED display circuit, an audio alarm output unit 15 including an audio circuit 15a and a speaker 15b, and an external output circuit that outputs alarm output determination information of the determination unit 6 to the outside according to a voltage level. 16. Based on the alarm output determination of the determination unit 6, the light alarm output unit 14, the audio alarm output unit 15, and the alarm output control unit 17 that outputs a predetermined control signal to the external output circuit 16 are configured. The Here, the alarm output control unit 17 is configured in the microprocessor 13 provided in the main body unit 1.

  The power supply unit 8 includes a power transformer 18, a smoothing circuit 19, and a constant voltage circuit 20, and generates a DC low voltage (for example, 5V, 3.3V) from a commercial AC voltage 100V for home use, for example. .

  Next, FIGS. 4 and 5 show the external configuration of the device of the present invention. FIG. 4A is a perspective view seen from the front side of the main body 1, and the LEDs 14 a of three colors (red, green, and yellow) of the LED display circuit of the light alarm output unit 14 are provided in the lower left area of the front surface. A speaker 15b of the voice alarm output unit 15 is provided in the lower right area of the front surface, a recess 21 for fitting the sensor module unit 2 is provided in the upper part of the speaker 15b, and a sensor module is installed on the back side of the bottom of the recess 21. A connector 22 for electrically connecting the part 2 and the body part 1 is fixed. A screw hole 23 for fixing the sensor module 2 by screwing is provided on the rear side of the edge of the recess 21 on the upper surface of the main body 1. A power cord 25 having a power plug 24 at the tip is connected to the power source 8 and is drawn out from the back of the main body 1.

  FIG. 4B shows a state in which the sensor module unit 2 is fitted in the recess 21 of the main body unit 1 and fixed by screwing. 5A, 5B, 5C, and 5D are respectively a perspective view of the sensor module unit 2 viewed from the bottom side, a perspective view viewed from the front side, and a perspective view viewed from the back side. And a side view. As shown in FIG. 5A, a connector (connecting pin) 26 is provided on the bottom surface of the sensor module unit 2 so as to be engaged with the connector 22 of the main body unit 1 for electrical connection. . Each connection pin of the connector 26 includes an input terminal such as a sensor output terminal 12 of the sensor unit 3 provided in the sensor module unit 2 or a base (or gate) terminal of the switching transistor T, a power supply voltage terminal, a ground terminal, and a sensitivity. The adjustment element storage means 4 is connected to each input terminal, each output terminal, a power supply voltage terminal, a ground terminal, and the like. Further, as shown in FIGS. 5B and 5C, a part of the upper surface of the sensor module portion 2 protrudes rearward from the rear surface, and a screw hole 27 for screwing with the main body portion 1 is provided. . As shown in FIGS. 5A, 5B, and 5D, on the front surface of the sensor module unit 2, a detection target gas in the surrounding atmosphere is provided on the sensor unit 11 provided in the internal sensor unit 3. A slit 28 is provided for introducing the slit.

  The positions of the LED 14a, speaker 15b, connector (connection pin) 26, screw hole 27, and slit 28 are not necessarily limited to the positions shown in FIG. The LED 14a may be a position that is easily visible from the outside, and the position of the speaker 15b may be a position where the output sound is easily diffused.

  The shape of the recess 21 of the main body 1, the position of the connector 22 and the screw hole 23, and the shape of the sensor module 2, the position of the connector (connection pin) 26 and the screw hole 27 are made common among different alarm devices. Thus, a plurality of types of sensor module units 2 can be used in common for the same main body unit 1, and the same sensor module unit 2 can be used for a plurality of types of main unit units 1.

  Next, the operation of the apparatus of the present invention shown in FIG. 1 will be described with reference to the flowchart of FIG. When the power plug 24 of the main unit 1 is inserted into an AC outlet and the power is turned on, the commercial AC power is converted into DC power in the power unit 8 and power is supplied to the main unit 1 and the sensor module unit 2 of the apparatus of the present invention. Start (step # 1).

  The microprocessor 13 of the main body 1 executes a startup program, and executes a series of data reading processing from the sensitivity adjustment element storage unit 4 built in the sensor module 2 shown below. First, the counter value N is reset to 0, and the sensitivity adjustment element storage means 4 waits for a predetermined time α seconds (for example, 0.5 seconds) until it becomes stable after power is turned on (step # 2), and sensitivity adjustment is performed. An attempt is made to read connection confirmation data of the sensor module unit 2 from the element storage unit 4 (step # 3). Next, the connection confirmation data is confirmed (step # 4), and if the connection confirmation data cannot be read from the sensitivity adjustment element storage means 4, the sensor module 2 is not connected to the main body 1. Since it is determined as a connected state and does not function as a normal alarm device, a non-connection state detection signal is output to the alarm output unit 7, and the alarm output unit 7 switches the LED display to a predetermined error alarm display (step) # 5). For example, the green LED is turned off and the red LED is turned on. Thereafter, in order to retry the reading of the connection confirmation data of the sensor module unit 2 at regular intervals, after waiting for a predetermined time β seconds (step # 6), the process returns to step # 3. Here, the waiting time β seconds is necessary because the microprocessor 13 confirms the connection of the sensor module unit 2 after the sensor module unit 2 is connected and informs the operator of the normal operation state. In consideration of workability, it is preferably as short as possible in 30 seconds or less.

  In the confirmation of the connection confirmation data (step # 4), when the connection confirmation data can be read from the sensitivity adjustment element storage means 4, the sensitivity adjustment element and the control parameter data are stored from the sensitivity adjustment element storage means 4. Read (step # 7). Next, each data of the sensitivity adjustment element and the control parameter is read again from the sensitivity adjustment element storage unit 4 (step # 8). Then, the data read in step # 7 and step # 8 are collated (step # 9). If the data read in the verification process does not match, the counter value N is counted up (step # 10), it is determined whether the counter value N has reached the maximum value Nmax (step # 11), and the maximum value Nmax is reached. If not reached, after waiting for a predetermined time γ seconds (for example, 0.2 seconds) (step # 12), the process returns to step # 7, and the processes of steps # 7 to # 9 are repeated. If the counter value N reaches the maximum value Nmax in step # 11, a data error detection signal is output to the alarm output unit 7, and the alarm output unit 7 switches the LED display to a predetermined error alarm display. (Step # 13). At this time, the error alarm at the time of non-contact detection and data error detection may be changed.

  If the data read in the collation process in step # 9 matches, the read data is stored in a memory (not shown) built in the main body 1 (step # 14). After waiting for a predetermined time δ seconds (for example, 0.2 seconds) (step # 15), the sensor module unit 2 by the drive control unit 5 based on the sensitivity adjustment element and the control parameter read from the sensitivity adjustment element storage unit 4 The drive control for the sensor unit 3 and the alarm output determination for the sensor output output from the sensor unit 3 by the determination unit 6 are started (step # 16).

  Based on the control parameters read from the sensitivity adjustment element storage unit 4 to detect two types of detection target gases, methane and carbon monoxide, the drive control unit 5 has a timing and a duty ratio as shown in FIG. The temperature control of the heater 10 of the sensor element 11 is executed. At the same time, the on / off control of the switching transistor T of the sensor unit 3 is also performed in synchronization with the timing shown in FIG. Specifically, the switching transistor T is turned on when carbon monoxide is detected.

  The determination unit 6 outputs the respective sensor outputs at the detection timing of the sensor output for methane detection shown in FIG. 3 and the detection timing of the sensor output for carbon monoxide detection shown in FIG. 3 of the control parameters read from the sensitivity adjustment element storage unit 4. The read sensor output, the detection threshold voltage for detection of methane of the sensitivity adjustment element read from the sensitivity adjustment element storage means 4, or the detection threshold voltage after temperature correction of the detection threshold voltage for detection of carbon monoxide In comparison, it is determined whether or not the concentration of methane or carbon monoxide is equal to or higher than the detection specified concentration. If the concentration of methane is equal to or higher than the detection specified concentration of methane, it is determined that a gas leak has occurred and A determination signal is output, and when the concentration of carbon monoxide is equal to or higher than the detection specified concentration, it is determined that the combustion state is incomplete and an incomplete combustion determination signal is output.

  Hereinafter, a case where the detection threshold voltage for methane detection is set in two stages will be described as an example. The determination unit 6 compares the sensor output with the detection threshold voltage after temperature correction for methane detection at the first stage (e.g., corresponding to a detection regulation concentration of 500 ppm), and the methane concentration is the detection regulation concentration at the first stage (500 ppm). ) If the methane concentration is equal to or higher than the first-stage detection specified concentration, it is determined that a first-stage (mild) gas leak has occurred, and the first-stage gas leak determination signal Is output to the alarm output control unit 17 of the alarm output unit 7. The alarm output control unit 17 controls each alarm output of the light alarm output unit 14, the audio alarm output unit 15, and the external output circuit 16 based on the first-stage gas leak determination signal. For example, as an example, in the case of the first stage (mild) gas leak alarm, the red LED blinks at a constant frequency (for example, 2 Hz) to the light alarm output unit 14 and the sound alarm output unit 15 A melody sound is output and a voltage of 6 V is output to the external output circuit 16.

  Further, the determination unit 6 compares the sensor output with the detection threshold voltage after temperature correction for the second stage methane detection (for example, corresponding to the detection specified concentration of 3500 ppm), and the methane concentration is the second level detection specified concentration. It is determined whether or not it is (3500 ppm) or more, and if the methane concentration is equal to or higher than the detection standard concentration of the second stage, it is determined that the second stage (severe) gas leakage has occurred and the second stage gas leakage The determination signal is output to the alarm output control unit 17 of the alarm output unit 7. The alarm output control unit 17 controls each alarm output of the light alarm output unit 14, the audio alarm output unit 15, and the external output circuit 16 based on the second-stage gas leak determination signal. For example, in the case of the second stage (severe) gas leak alarm, for example, a red LED is always lit on the light alarm output unit 14 and an alarm sound (for example, “ , Etc.) and an alarm message (for example, “gas leaks” etc.) are sequentially output, and a voltage of 12 V is output to the external output circuit 16.

  Next, a method of storing the sensitivity adjustment element related to the sensor element 11 built in the sensor unit 3 in the sensitivity adjustment element storage unit 4 when the sensor module unit 2 is manufactured will be described.

  The sensitivity adjustment factor in the factory, for example, the setting of the sensor output voltage value (detection threshold voltage) at a predetermined detection specified concentration is set in a predetermined temperature and humidity (for example, in a chamber of a setting device (not shown)). , 20 ° C., 65%). In this state, the connector 26 (see FIG. 4) of the sensor module unit 2 to be set is connected to each connector of the evaluation board provided in the setting device in which the plurality of sensor module units 2 can be mounted. Then, power is supplied to each mounted sensor module unit 2, and the setting control unit drives the sensor unit 3 including the heater 10 with respect to the sensor unit 3 by the same driving method as that used when the sensor unit 3 is mounted on the main body unit 1. . The setting device issues a command to the concentration adjusting means for the gas to be evaluated (for example, methane or carbon monoxide) so that the gas concentration is maintained at the detection specified concentration in the chamber. The concentration adjustment means adjusts the amount of gas to be introduced so as to achieve the target detection prescribed concentration while monitoring the gas concentration in the chamber with the calibration sensor in the chamber, and can maintain the target detection prescribed concentration. Then, a signal indicating that the gas concentration in the chamber is the specified detection concentration is output to the setting control means corresponding to the sensor module unit 2 to be set. The setting control means is provided corresponding to each sensor module unit 2 on the evaluation substrate, and includes a microprocessor in the same manner as the microprocessor 13 of the main body unit 1.

  When the setting control means receives a signal indicating that the gas concentration is the specified detection concentration, the setting control means is adapted to the detection timing suitable for the type of gas to be detected (usually the same as when operating as an alarm device connected to the main unit 1). At the timing), the sensor output of the sensor module unit 2 to be set is read, and the detection threshold voltage corresponding to the detection prescribed concentration in the chamber binarized by A / D conversion is set to a predetermined value in the sensitivity adjustment element storage unit 4. Write to storage area.

  In the above manner, the detection threshold voltages of the first and second stages of methane and the detection threshold voltages of the first and second stages of carbon monoxide are written in the sensitivity adjustment element storage unit 4. As for the control parameters, those suitable for the driving method corresponding to the circuit configurations of the sensor element 11 and the sensor unit 3 are written in the sensitivity adjustment element storage unit 4 together with the sensitivity adjustment elements.

  Next, replacement of the sensor module unit 2 of the device of the present invention will be described. It is assumed that the device of the present invention is installed at a predetermined place of use and the sensor module 11 is replaced after the expiration date (for example, 5 years) of the sensor element 11 built in the sensor module 2 expires.

  Normally, when replacing the sensor module unit 2, the power plug 24 of the main body unit 1 is removed from the AC outlet, and after turning off the power, the used sensor module unit 2 is removed from the main body unit 1. After the new sensor module unit 2 is attached to the main unit 1, the power plug 24 of the main unit 1 is inserted into an AC outlet and the power is turned on. After the power is turned on, it is started in the same procedure as described with reference to the flowchart of FIG. 6 described above, and the drive control for the sensor unit 3 of the sensor module unit 2 by the drive control unit 5 and the sensor unit 3 by the determination unit 6 Alarm output determination for the sensor output output from is started.

  Here, a case where the sensor module unit 2 is replaced while the power plug 24 of the main unit 1 is inserted into the AC outlet, that is, in a power-on state will be described.

  When the sensor module unit 2 is removed from the main unit 1 in the power-on state, no sensor output is input to the analog port of the microprocessor 13 of the main unit 1 that receives the sensor output. Instead, the input level is clamped through a resistor, for example, so that the input level of the analog port becomes 0 V in a high resistance state. The high resistance state in this case is a high resistance state of, for example, three digits or more than the load resistance connected to the sensor output terminal 12 of the sensor unit 3 or the resistance fluctuation range of the sensor element 11.

  When the microprocessor 13 of the main body 1 detects the sensor output 0V, the microprocessor 13 starts a determination program that determines whether the sensor output 0V is due to the failure of the sensor element 11 or the sensor module 2 being removed. .

  When the determination program is activated, the microprocessor 13 attempts to read connection confirmation data of the sensor module unit 2. Here, when the connection with the sensor module unit 2 is confirmed, it is determined that the sensor output 0V is due to the failure of the sensor element 11, and a failure detection signal of the sensor element 11 is output to the alarm output unit 7, The alarm output unit 7 switches the LED display to a predetermined error alarm display.

  If the connection with the sensor module unit 2 is not confirmed, the connection confirmation data of the sensor module unit 2 is read a predetermined number of times, and if the connection with the sensor module unit 2 is not finally confirmed, the sensor output is 0V. Is determined to be due to the removal of the sensor module unit 2, and the alarm output unit 7 outputs an unconnected state detection signal of the sensor module unit 2 to the alarm output unit 7, and the alarm output unit 7 displays the LED display in a predetermined unconnected state detection display. Switch to. Thereafter, the microprocessor 13 periodically tries to read connection confirmation data of the sensor module unit 2.

  Next, when a new sensor module unit 2 is connected to the main body unit 1, the microprocessor 13 reads connection confirmation data of the sensor module unit 2 and confirms the connection of the sensor module unit 2. Since the process after the connection confirmation is the same procedure as the process after step # 7 in the flowchart of FIG. 6, the overlapping description is omitted.

Second Embodiment
Next, a second embodiment of the device of the present invention will be described. FIG. 7 shows a circuit configuration of the device of the present invention according to the second embodiment. The same components as those in the first embodiment will be described with the same reference numerals. As shown in FIG. 7, the device of the present invention according to the second embodiment includes a sensor module unit 2 that is detachable from the main body unit 1 as in the first embodiment. The hardware configuration of the main body 1 and the external configuration of the device of the present invention are the same as those of the first embodiment. The sensor element 11 of the sensor unit 3 is a semiconductor gas sensor that can selectively detect two types of detection target gases, methane and carbon monoxide, by the drive control of the heater, and the circuit configuration of the sensor unit is also the first. This is the same as the embodiment. Therefore, the description which overlaps about these is abbreviate | omitted.

  The difference from the first embodiment shown in FIG. 1 is that the drive control for the heater 10 of the sensor unit 3 of the sensor module unit 2 uses PWM control in the first embodiment, but the applied voltage is applied in the second embodiment. Directly control the voltage value. FIG. 8 shows the voltage waveform applied to the heater 10 and the detection timing of the sensor output. As shown in FIG. 8, 0.9 V is applied for 5 seconds when methane is detected, and 0.2 V is applied for 10 seconds when carbon monoxide is detected, and each sensor output is detected at the end of each application period.

  In the second embodiment, voltage control means 29 for adjusting the voltage value applied to the heater 10 is provided in the sensor module unit 2 in order to control the amplitude of the voltage applied to the heater 10. FIG. 9 shows a circuit configuration of the voltage adjusting means 29. The voltage adjusting means 29 uses two reference voltages Vref1 (applied voltage 0.9 V when detecting methane shown in FIG. 8) and Vref2 (applied voltage 0.2 V when detecting carbon monoxide shown in FIG. 8). It is composed of a resistance voltage dividing circuit that is alternatively generated by an off operation and connected to one differential input terminal of the operational amplifier, and an operational amplifier whose output is fed back to the other differential input terminal. ON / OFF of the switch of the resistance voltage dividing circuit is controlled by a control signal from the drive control unit 5 of the main body unit 1. The on / off control of the switch is performed in synchronization with the on / off control of the switching transistor T.

  Similar to the first embodiment, the sensitivity adjustment element stored in the sensitivity adjustment element storage unit 4 is the detection threshold voltage of the sensor output at a predetermined detection specified concentration. The method for setting the detection threshold voltage is also the same as that in the first embodiment, and a duplicate description is omitted.

  In the case of the second embodiment, the control parameters stored in the sensitivity adjustment element storage means 4 are the voltage application start timing, end timing, and sensor output detection by amplitude control for methane detection as shown in FIG. Timing, voltage application start timing, end timing, and sensor output detection timing by amplitude control for carbon monoxide detection are assumed. In the case of the second embodiment, since the voltage adjusting means 29 is provided in the sensor module unit 2 and the applied voltage is adjusted by amplitude control by the voltage adjusting means 29, it is for methane detection and carbon monoxide detection. Each voltage value need not be stored as a control parameter.

<Third Embodiment>
Next, a third embodiment of the device of the present invention will be described. FIG. 10 shows a circuit configuration of the device of the present invention according to the third embodiment. The same components as those in the first embodiment will be described with the same reference numerals. As shown in FIG. 10, the device of the present invention according to the third embodiment includes a sensor module unit 2 that is detachable from the main body unit 1 as in the first embodiment. The external configuration of the device of the present invention is the same as that of the first embodiment. Therefore, the description which overlaps about these is abbreviate | omitted.

  The difference from the first embodiment shown in FIG. 1 or the second embodiment shown in FIG. 7 is that, as shown in FIG. 10, the sensor module unit 2 includes a plurality of sensor units 3 (in this third embodiment). Two sensor units 3A, 3B), voltage adjusting means 29A, 29B corresponding to each of the sensor units 3A, 3B, an amplifier circuit 30 for sensor output of the sensor unit 3A, and a sensitivity adjustment element storage unit 4. It is a point. Each of the sensor units 3A and 3B includes a sensor element that is sensitive to a different detection target gas. For example, the sensor unit 3A has a sensor element dedicated to methane, and the sensor unit 3B has a sensor element dedicated to carbon monoxide. Is provided.

  FIGS. 11 and 12 illustrate the applied voltage pattern for driving the heater of the sensor unit 3A, the applied voltage waveform for driving the heater of the sensor unit 3B, and the detection timing of the sensor output, respectively. As shown in FIGS. 11 and 12, also in the third embodiment, the heater drive control of each of the sensor units 3A and 3B is amplitude control for directly controlling the voltage value of the applied voltage, and the sensor unit 3A for detecting methane. For example, a 2.0 V application for 2.5 seconds and a 0 V application for 7.5 seconds are periodically repeated, the sensor output is detected at the end of the 2.0 V application period, and a sensor unit for detecting carbon monoxide For 3B, 1.2V application for 60 seconds and 0V application for 90 seconds are periodically repeated, and the sensor output is detected at the end of the 0V application period. Further, since the voltage pulse applied to each of the sensor units 3A and 3B has a single voltage amplitude, one of the reference voltages Vref1 and Vref2 of the voltage adjusting means 29A and 29B becomes the ground potential (0 V), and one resistance A voltage dividing circuit is not required, and the circuit configuration is simplified.

  Further, since the sensor output detection timing is at the end of a relatively long period when the heater is not driven, the sensor unit 3B drives the load resistor for reading of the sensor unit 3B only at the time of detection (applies a power supply voltage). And a circuit configuration for reading the sensor output. Here, the drive control of the load resistance is performed by a control signal of the drive control unit 5 of the main body unit 1.

  The sensitivity adjustment element stored in the sensitivity adjustment element storage unit 4 is a detection threshold voltage of each sensor output of the sensor units 3A and 3B at a predetermined detection specified concentration. In the case of the third embodiment, methane and carbon monoxide can be detected separately by the two sensor units 3A and 3B, and the detection target gas species is the same as in the first and second embodiments. The sensitivity adjustment elements stored in the storage unit 4 are the same as those in the first and second embodiments. Also, the method for setting the detection threshold voltage is basically the same as that in the first embodiment, and therefore, a duplicate description is omitted.

  In the case of the third embodiment, the control parameters stored in the sensitivity adjustment element storage unit 4 are the voltage application start timing, end timing, and sensor output detection by amplitude control for methane detection as shown in FIG. The timing and the voltage application start timing, end timing, and sensor output detection timing by the amplitude control for detecting carbon monoxide as shown in FIG. 12 are assumed. In the case of the third embodiment, the voltage adjusting means 29A and 29B are provided in the sensor module unit 2, and the applied voltage is adjusted by amplitude control by the voltage adjusting means 29A and 29B. Each voltage value for carbon detection need not be stored as a control parameter.

  As shown in FIG. 10, the drive control unit 5 of the main body unit 1 includes necessary control signals according to the number of sensor units 3 </ b> A and 3 </ b> B in the sensor module unit 2. In the first and second embodiments, the sensor element itself has a methane detection capability and a carbon monoxide detection capability and is configured to drive both detection capabilities in a time-sharing manner. Therefore, methane detection and carbon monoxide detection are performed. However, in the third embodiment, since the sensor unit 3A having methane detection capability and the sensor unit 3B having carbon monoxide detection capability are provided in parallel, the drive control unit 5 This drive control does not need to be performed in a time-sharing manner, and separate drive control is performed for methane detection and carbon monoxide detection.

  As shown in FIG. 10, the determination unit 6 of the main body unit 1 provides input terminals for each sensor output in accordance with the number of sensor units 3A and 3B in the sensor module unit 2 and reads them individually. Specifically, each sensor output is read at the detection timing shown in FIG. 11 and FIG. 12 of the control parameter read from the sensitivity adjustment element storage unit 4, temperature correction processing is performed separately, and alarm output determination is performed. The alarm output determination and the subsequent alarm output process are basically the same as those in the first and second embodiments, and thus redundant description is omitted.

<Fourth embodiment>
Next, a fourth embodiment of the device of the present invention will be described. FIG. 13 shows a circuit configuration of the device of the present invention according to the fourth embodiment. The circuit configuration shown in FIG. 13 is based on the circuit configuration of the first embodiment, and a contact resistance detecting means for detecting a parasitic resistance component on the contact between the main body 1 and the sensor module 2 on the main body 1 side. 31 is provided.

  As shown in FIG. 13, contact resistance detection is provided by providing a lead-out point on the sensor module 2 side for the power supply terminal, ground terminal, etc. through which a large amount of current flows, among the connection terminals of the main body 1 and the sensor module 2. Are connected to the terminals 32 and 33.

  In the start-up operation of the device of the present invention described in the first embodiment, for example, in the confirmation of the connection confirmation data in step # 4 of the flowchart shown in FIG. 6, the connection confirmation data is read from the sensitivity adjustment element storage unit 4. If it can be output, the contact resistance detection means 31 is activated to start the operation of reading out each data of the sensitivity adjustment element and control parameter from the sensitivity adjustment element storage means 4 in step # 7, and the power supply terminal and its contact A current is passed between the resistance detection terminals, and the parasitic resistance component is measured by the voltage difference between the two terminals. When the parasitic resistance component is equal to or greater than the specified value, the microprocessor 13 of the main body 1 outputs a contact resistance abnormality detection signal to the alarm output unit 7, and the alarm output unit 7 changes the LED display to a predetermined error alarm display. Switch. The operator adjusts the connection state of the sensor module unit 2 and the main body unit 1 by the error alarm display, and can eliminate the contact resistance abnormality or find an abnormality early as a defective product when adjustment is difficult.

  In the above description, an example in which the contact resistance detection means 31 is provided in the main body 1 and the contact resistance detection terminals 32 and 33 are separately added has been described based on the circuit configuration of the first embodiment. The configuration may be performed based on the second or third embodiment.

  Hereinafter, another embodiment will be described.

  <1> In each of the above embodiments, the case where the sensitivity adjustment element storage unit 4 is configured by a nonvolatile semiconductor memory capable of electrically erasing and writing data such as an EEPROM has been described. Instead of or in addition to the nonvolatile semiconductor memory, an electric element capable of storing information in an analog manner such as a variable resistance element may be used.

  When a variable resistance element is used for storing the sensitivity adjustment element, for example, as shown in FIG. 14, the variable resistance element is used for the load resistors R <b> 1 and R <b> 2 for reading the sensor output of the sensor unit 3. Sensor output voltage value (detection threshold voltage) at a predetermined detection specified concentration in a predetermined temperature and humidity atmosphere (for example, 20 ° C., 65%) in the step of setting the sensitivity adjustment element during manufacture in However, the sensitivity adjustment element can be substantially stored by adjusting the resistance value of the variable resistance element so that it becomes a predetermined constant value (determination reference value). In this case, a temperature correction process is performed on the constant value (determination reference value) of the main body 1 to perform alarm output determination.

  Further, as the sensitivity adjustment element storage means 4, when a nonvolatile semiconductor memory and a variable resistance element are used in combination, a control parameter for driving control of the sensor unit 3 of the sensor module unit 2 is stored in the nonvolatile semiconductor memory. Can do.

  Further, in each of the above embodiments, the case where the sensitivity adjustment element storage unit 4 stores the sensitivity adjustment element and the control parameter has been described. However, only the sensitivity adjustment element may be stored in the sensitivity adjustment element storage unit 4. Absent.

  <2> In the operation at the time of startup shown in the flowchart of FIG. 6 of the first embodiment, the connection confirmation data need not be read from the sensitivity adjustment element storage unit 4. For example, a terminal dedicated for reading connection confirmation data may be provided in the main body 1 and the sensor module unit 2 to read a predetermined voltage applied to the terminal on the sensor module unit 2 side in a connected state. Absent. Further, the contact resistance detection means 31 described in the fourth embodiment may be used. In other words, for example, if a current is passed between a power supply terminal and a corresponding contact resistance detection terminal to detect energization, the connection state can be confirmed.

  <3> In the second and third embodiments, the voltage adjusting unit 29 is provided in the sensor module unit 2. However, the voltage adjusting unit 29 may be provided on the main unit 1 side. In this case, the reference voltages Vref1, 2 and the like for adjusting the applied voltage to the sensor unit 2 are generated by a control signal specifying the reference voltage from the drive control unit 5, and the specified value of the reference voltage is a sensitivity adjustment. The control parameters stored in the element storage means 4 are used. Therefore, the control parameter stored in the sensitivity adjustment element storage unit 4 stores the voltage value of the applied voltage in addition to the voltage application start timing, the end timing, and the sensor output detection timing by amplitude control.

  <4> In the third embodiment, the heater drive control of the sensor element dedicated to methane of the sensor unit 3A and the sensor element dedicated to carbon monoxide of the sensor unit 3B is described as the case of amplitude control of the applied voltage. However, effective control of the applied voltage may be performed from the main body 1 side by PWM control. In this case, the voltage adjustment means 29A and 29B are not necessary. Instead, the sensitivity adjustment element storage means 4 stores the duty ratio of each applied voltage pulse as a control parameter, and each sensor unit by PWM control based on the duty ratio. 3A and 3B drive control may be performed.

  <5> In the third embodiment, the case where a plurality of sensor units 3 are provided in the sensor module unit 2 has been described. However, in the initial shipment state, the number of sensor units 3 mounted in the sensor module unit 2 is determined. However, it may be less than the maximum number. However, the maximum number of terminals of the connector between the sensor module unit 2 and the main unit 1, the number of control signals of the drive control unit 5 on the main unit 1 side, and the number of inputs for receiving the sensor output of the determination unit 6 are the maximum. Prepare in advance corresponding to the number of sensor units 3. Further, as the control parameter stored in the sensitivity adjustment element storage unit 4, for example, data specifying an effective sensor unit is stored, and the main body unit 1 is effective by reading the control parameter in the process at the time of activation. It is only necessary to determine the sensor unit, read other control parameters related to the effective sensor unit, perform drive control only on the effective sensor unit, read the sensor output, and perform the alarm output determination. .

  By configuring as described above, by replacing the alarm device initially shipped as a gas leak alarm device with a sensor module unit 2 in which a sensor unit having carbon monoxide detection capability is added, gas leakage and incomplete combustion are prevented. The function can be improved to a composite type alarm device that detects and issues an alarm.

  <6> In each of the above embodiments, the sensor element built in the sensor module unit 2 is assumed to be a semiconductor gas sensor having methane detection capability, carbon monoxide detection capability, or both. The built-in sensor element is not limited to the semiconductor gas sensor, and the detection target of the sensor element is not limited to methane or carbon monoxide. For example, you may provide the sensor part which detects abnormally high temperature and smoke, and detects a fire state.

  <7> Each voltage value, timing, or gas concentration exemplified in each of the above embodiments is an example, and is not limited to the voltage value, timing, gas concentration, etc. of each of the above embodiments, and can be changed as appropriate. It is.

  <8> In each of the above embodiments, as shown in FIG. 4, as an external configuration of the device of the present invention, a configuration in which the sensor module unit 2 is fitted into and integrated with the recess 21 provided in the main body unit 1 is illustrated. However, for example, as illustrated in FIG. 15, the main body 1 and the sensor module 2 may be connected by a connection cable 34, and the main body 1 and the sensor module 2 may be installed separately.

  <9> In each of the above embodiments, the power supply unit 8 of the main body unit 1 includes the power transformer 18, the smoothing circuit 19, and the constant voltage circuit 20, and converts AC power supplied from the outside into DC power. The power supply unit 8 is configured using a built-in battery, and the DC voltage of the built-in battery is supplied to the main unit 1 and the sensor module unit 2. The configuration may be such that each unit is supplied directly or via a DC / DC converter or the like.

The circuit block diagram which shows the circuit structural example in 1st Embodiment of the alarm device which concerns on this invention. The circuit block diagram which shows the circuit structural example of the sensor part which has the detection ability with respect to two types of detection object gas of methane and carbon monoxide provided in the sensor module part in 1st Embodiment of the alarm device which concerns on this invention. Voltage waveform diagram showing the detection timing of the voltage waveform and sensor output when the heater of the sensor unit shown in FIG. 2 is driven and controlled by PWM control The figure which shows the external appearance structure of the alarm device which concerns on this invention, and its main-body part. The figure which shows the external appearance structure of the sensor module part of the alarm device which concerns on this invention The flowchart explaining the operation | movement at the time of starting of the alarm device which concerns on this invention The circuit block diagram which shows the circuit structural example in 2nd Embodiment of the alarm device which concerns on this invention. Voltage when driving and controlling the heater of the sensor unit having the ability to detect two types of detection target gases, methane and carbon monoxide, provided in the sensor module unit in the second embodiment of the alarm device according to the present invention. Voltage waveform diagram showing waveform and sensor output detection timing The circuit diagram which shows the circuit structure of the voltage adjustment means 29 in 2nd Embodiment of the alarm device which concerns on this invention. The circuit block diagram which shows the circuit structural example in 3rd Embodiment of the alarm device which concerns on this invention. Voltage waveform diagram showing voltage waveform and sensor output detection timing when the heater of the sensor unit having methane detection capability provided in the sensor module unit according to the third embodiment of the present invention is driven and controlled by amplitude control. The voltage which shows the detection timing of a voltage waveform and sensor output in the case of carrying out drive control of the heater of the sensor part which has the carbon monoxide detection capability provided in the sensor module part in 3rd Embodiment of the alarm device which concerns on this invention by amplitude control Waveform diagram The circuit block diagram which shows the circuit structural example in 4th Embodiment of the alarm device which concerns on this invention. Circuit block diagram showing a circuit configuration example of a sensor unit when a variable resistance element is used as a sensitivity adjustment element storage unit The figure which shows another external appearance structural example of the sensor module part of the alarm device which concerns on this invention

Explanation of symbols

1: Body unit 2: Sensor module unit 3, 3A, 3B: Sensor unit 4: Sensitivity adjustment element storage unit 5: Drive control unit 5a: Sensor drive unit 5b: Pulse control unit 6: Judgment unit 7: Alarm output unit 8: Power supply unit 9: Temperature sensor 10: Heater 11: Sensor element 12: Sensor output terminal 13: Microprocessor 14: Light alarm output unit 14a: LED
15: Audio alarm output unit 15a: Audio circuit 15b: Speaker 16: External output circuit 17: Alarm output control unit 18: Power transformer 19: Smoothing circuit 20: Constant voltage circuit 21: Recess 22: Connector 23: Screw hole 24: Power supply Plug 25: Power cord 26: Connector (connection pin)
27: Screw hole 28: Slit 29, 29A, 29B: Voltage adjusting means 30: Amplifying circuit 31: Contact resistance detecting means 32, 33: Contact resistance detecting terminal 34: Connection cable R1, R2: Load resistance
T: switching transistor Vcc: power supply voltage Vref1: reference voltage Vref2: reference voltage

Claims (19)

An alarm device comprising a sensor module part detachable from the main body part,
The sensor module unit includes a sensor unit that converts the property change of a sensor element that exhibits detectability by changing the property with respect to a predetermined detection target, and outputs the electrical signal, and a sensitivity adjustment element of the sensor unit Sensitivity adjustment element storage means for storing
The main body includes a drive control unit that controls driving of the sensor unit, a determination unit that determines whether to output an alarm based on a sensor output output from the sensor unit, and an alarm output unit that outputs the alarm And the alarm device characterized by including the power supply part which supplies predetermined | prescribed electric power to each part of the said main-body part and the said sensor module part.   The alarm device according to claim 1, wherein a semiconductor gas sensor is included as the sensor element included in the sensor module unit.   The alarm device according to claim 2, wherein the semiconductor gas sensor is capable of detecting at least one of a combustible gas and carbon monoxide.   The sensor unit includes a semiconductor gas sensor capable of detecting both flammable gas and carbon monoxide as the sensor element, and a load capable of selecting a resistance value corresponding to a detection target gas type by a control signal from the drive control unit. The alarm device according to claim 3, further comprising a resistance circuit.   The alarm device according to claim 1, wherein the sensor module unit includes a variable resistance element as the sensitivity adjustment element storage unit.   The alarm device according to claim 1, wherein the sensor module unit includes a nonvolatile semiconductor memory as the sensitivity adjustment element storage unit.   The determination unit reads out sensitivity adjustment element data related to the sensitivity adjustment element stored in the nonvolatile semiconductor memory, and sets a determination criterion for the sensor output based on the sensitivity adjustment element data. 6. The alarm device according to 6.   The alarm device according to claim 6 or 7, wherein the nonvolatile semiconductor memory can store a control parameter for the drive control unit to perform drive control on the sensor unit.   9. The alarm device according to claim 8, wherein the drive control unit reads the control parameter stored in the nonvolatile semiconductor memory, and performs drive control on the sensor unit based on the read control parameter. .   The alarm device according to claim 8 or 9, wherein the control parameter includes a parameter defining a voltage waveform applied to a predetermined node of the sensor unit.   The alarm device according to claim 8 or 9, wherein the control parameter includes a parameter that defines a duty ratio when a voltage is applied to a predetermined node of the sensor unit by PWM control.   The alarm device according to any one of claims 8 to 11, wherein the control parameter includes a parameter that defines a detection time point of the sensor output output from the sensor unit.   The alarm device according to claim 1, wherein the sensor module unit includes a voltage adjustment unit that adjusts a voltage value applied to a predetermined node of the sensor unit.   The alarm device according to any one of claims 1 to 13, further comprising contact resistance detection means for detecting a resistance component parasitic on a contact between the main body portion and the sensor module portion.   The alarm device according to claim 1, wherein the sensor module unit can be equipped with two or more sensor units having different detection targets.   16. At least one of information indicating the type of the sensor element and individual identification information of the sensor element is stored in the nonvolatile semiconductor memory. The alarm device according to item. A sensor module that is detachable from the main body of the alarm device according to any one of claims 1 to 16,
A sensor unit that converts the property change of a sensor element that exhibits detectability by changing the property with respect to a predetermined detection target and outputs the electrical signal, and a sensitivity for storing a sensitivity adjustment element of the sensor unit Adjustment element storage means,
The sensor unit is driven and controlled by a control signal from the main body, and is configured to output the electrical signal to the main body.
The sensitivity adjustment element storage means is configured to be able to output the stored data of the sensitivity adjustment element to the main body. An operation method of the sensor module which is detachable from the main body of the alarm device,
The sensor module is driven and controlled by a control signal from the main body, and converts the property change of the sensor element that exhibits the detectability by changing the property with respect to a predetermined detection target, and converts the property into an electrical signal. A sensor unit that outputs to the unit, and a sensitivity adjustment element storage unit configured to store at least the sensitivity adjustment element of the sensor unit and to output the stored data of the sensitivity adjustment element to the main body unit Become
A method for operating a sensor module, comprising: reading connection confirmation data from the sensor module; and reading the sensitivity adjustment element data from the sensitivity adjustment element storage unit when the connection confirmation data is read. . An operation method of the sensor module which is detachable from the main body of the alarm device,
The sensor module is driven and controlled by a control signal from the main body, and converts the property change of the sensor element that exhibits the detectability by changing the property with respect to a predetermined detection target, and converts the property into an electrical signal. A sensor unit that outputs to the unit, a sensitivity adjustment element of the sensor unit, and a control parameter for performing drive control on the sensor unit, and the stored sensitivity adjustment element and data of the control parameter are stored in the main body unit A sensitivity adjustment element storage means configured to be capable of output,
Reading the control parameter data from the sensitivity adjustment element storage means;
And a step of performing drive control on the sensor unit based on the read control parameter.

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