JP6645784B2 - Battery operated alarm - Google Patents

Description

  The present invention relates to a battery-operated alarm.

  Conventionally, a battery type alarm which can detect a battery voltage has been proposed. This battery-operated alarm is configured to issue a warning when the battery voltage is low. When the battery voltage is low, a low battery warning sound (voice message “Battery dead” and electronic sound “beep” is issued. ) To notify the user of the decrease in battery voltage (for example, see Patent Document 1).

  Further, a battery type alarm device having a reset function of resetting the microcomputer at various timings such as when the microcomputer is abnormal has been proposed. According to this alarm device, initialization can be performed by resetting, and a microcomputer abnormality or the like can be resolved (for example, see Patent Document 2).

JP 2013-178649 A JP 2012-198752 A

  Here, when the load is driven in the battery type alarm device, the battery voltage is reduced. For this reason, for example, as in Patent Literature 1, when the battery voltage becomes equal to or lower than a predetermined voltage and the alarm sounds (that is, when the load is driven), or when the battery voltage slightly exceeds the predetermined voltage, for some reason (for example, When the load is driven during the abnormality detection), the battery voltage is further reduced. Further, in an alarm device having a reset function such as a battery-type alarm device described in Patent Literature 2, for example, a microcomputer is used at the timing when the battery voltage further drops (when the battery voltage drops below a specific voltage lower than a predetermined voltage). May be reset.

  However, when resetting is performed at such a timing, the following problem occurs. FIG. 4 is a timing chart illustrating a voltage state of the battery-operated alarm device according to the comparative example.

  First, it is assumed that at time 0, the battery voltage slightly exceeds a predetermined voltage. Then, it is assumed that the load is driven for some reason at time t41. As a result, the battery voltage decreases. When the battery voltage becomes equal to or lower than the specific voltage at time t42, the microcomputer is reset. In addition, the peripheral circuits are stopped together with the reset of the microcomputer, and the electrical connection between the load driven at time t41 and the battery is also cut off. Therefore, at time t43, the battery voltage starts to increase. Then, at time t44, the battery voltage exceeds the specific voltage.

  When the voltage exceeds a specific voltage, the microcomputer starts to operate and peripheral circuits operate. Here, the battery-operated alarm is often subjected to an initial check, and various loads operate as the initial check immediately after the microcomputer is started. Therefore, at time t45, the battery voltage doubled to a state that slightly exceeds the predetermined voltage, but starts to decrease again at time t46 due to driving of the load in the initial inspection.

  Thereafter, at time t47, the battery voltage becomes equal to or lower than the specific voltage, so that the microcomputer is reset. When the microcomputer is reset, the peripheral circuits are stopped, and the electrical connection between the load and the battery driven in the initial inspection is also cut off. Therefore, at time t48, the battery voltage starts to increase. Then, at time t49, the battery voltage exceeds the specific voltage. Thereafter, the above operation is repeated.

  As described above, in the case where the technology of the battery-powered alarm described in Patent Literature 1 and the technology of the battery-powered alarm described in Patent Literature 2 are combined, the reset operation is repeated. In particular, when a sound such as “beep” is output in the initial inspection, a sound such as “beep” is repeatedly emitted along with the repetition of the reset.

  The present invention has been made to solve such a conventional problem, and an object of the present invention is to prevent a reset operation from being repeated when a microcomputer is reset based on a detected battery voltage. It is an object of the present invention to provide a battery-operated alarm which can be performed.

The battery-operated alarm device of the present invention is driven by battery power, outputs an alarm when an abnormal condition is detected by a function mounted on the microcomputer, notifies the abnormal condition, and performs an initial inspection after resetting the microcomputer. A first function of detecting a battery voltage, a function of notifying that the battery voltage detected by the first function is equal to or lower than a predetermined voltage, and a function of detecting the first function by the first function. A second function of turning off at least one of the peripheral circuits when the battery voltage is equal to or lower than a specific voltage lower than the predetermined voltage , and resetting the microcomputer when the battery voltage is equal to or lower than a reset voltage lower than the specific voltage. It has a third function of performing

  According to this battery-operated alarm, a function is provided to turn off at least one of the peripheral circuits when the detected battery voltage is equal to or lower than a specific voltage, and a microcomputer is provided when the battery voltage is equal to or lower than a reset voltage lower than the specific voltage Has the function of resetting Therefore, even when the battery voltage exceeds the specific voltage and becomes lower than the specific voltage due to, for example, driving of the load, the microcomputer is not reset unless the voltage becomes lower than the reset voltage. If the reset is not performed, the initial inspection is not performed, and the battery voltage does not drop again due to the driving of the load at the time of the initial inspection. Therefore, when resetting the microcomputer based on the detected battery voltage, repetition of the reset operation can be prevented.

Further, the battery-operated alarm device of the present invention is driven by the power of the battery, and outputs an alarm when the abnormal condition is detected by a function mounted on the microcomputer to notify the abnormal condition. A battery-operated alarm device for performing an initial check, a first function for detecting a battery voltage, and a second function for turning off at least one of peripheral circuits when the battery voltage detected by the first function is equal to or lower than a specific voltage. A third function of resetting the microcomputer when the battery voltage is equal to or lower than a reset voltage lower than the specific voltage; and a battery voltage detected by the first function is lower than the specific voltage and the reset voltage. If the specified voltage is equal to or higher than the specified voltage, the microcomputer executes a specific program, and if the battery voltage is lower than the specified voltage, the specified program is executed. And having a fourth function for prohibiting the execution of the program.

According to this battery-operated alarm, a function is provided to turn off at least one of the peripheral circuits when the detected battery voltage is equal to or lower than a specific voltage, and a microcomputer is provided when the battery voltage is equal to or lower than a reset voltage lower than the specific voltage. Has the function of resetting Therefore, even when the battery voltage exceeds the specific voltage and becomes lower than the specific voltage due to, for example, driving of the load, the microcomputer is not reset unless the voltage becomes lower than the reset voltage. If the reset is not performed, the initial inspection is not performed, and the battery voltage does not drop again due to the driving of the load at the time of the initial inspection. Therefore, when resetting the microcomputer based on the detected battery voltage, repetition of the reset operation can be prevented. Further, the microcomputer executes a specific program when the battery voltage is lower than the specific voltage and is equal to or higher than a specified voltage exceeding the reset voltage, and does not execute the specific program when the battery voltage becomes lower than the specified voltage. For this reason, when the battery voltage has not reached the reset voltage and is equal to or higher than the specified voltage at which there is a possibility of power recovery, a specific program (for example, a program for maintaining the state at the time of turning off peripheral circuits, a gas detection timing of a gas alarm device, (A time measurement program of a sampling timer for measuring time) can be executed to prepare for power recovery.

  Further, in the battery-operated alarm device of the present invention, when the microcomputer is reset by the third function, the battery voltage detected by the first function is the execution of the specific program prohibited by the fourth function. It is preferable that the prohibition is continued until the return voltage exceeds the specific voltage.

  According to this battery-operated alarm, when the microcomputer is reset, the execution of a specific program is continuously prohibited until the battery voltage becomes equal to or higher than the return voltage exceeding the specific voltage. By executing the program, the battery voltage can be prevented from lowering again, which can lead to repetition of the reset operation.

  According to the present invention, it is possible to provide a battery-operated alarm that can prevent the reset operation from being repeated when the microcomputer is reset based on the detected battery voltage.

It is a lineblock diagram showing a battery type alarm concerning an embodiment of the present invention. FIG. 2 is a functional block diagram of the microcomputer shown in FIG. 1. It is a timing chart which shows the voltage condition of the battery type gas alarm device concerning this embodiment. It is a timing chart which shows the voltage condition of the battery type alarm device concerning a comparative example.

  Hereinafter, the present invention will be described along preferred embodiments. Note that the present invention is not limited to the embodiments described below, and can be appropriately changed without departing from the spirit of the present invention. In addition, in the embodiments described below, some components are not illustrated or described, but the details of the omitted technology are within a range that does not cause inconsistency with the content described below. Needless to say, a well-known or well-known technique is appropriately applied.

  FIG. 1 is a configuration diagram showing a battery-operated alarm device according to an embodiment of the present invention. In the following, a battery-operated gas alarm will be described as an example of a battery-operated alarm. However, the battery-operated alarm is not limited to a battery-operated gas alarm, but may be another alarm such as a battery-powered fire, CO, or human being. Or a battery-operated alarm that combines the functions of two or more alarms.

  As shown in the figure, the battery-operated gas alarm 1 is driven by the power of the battery 20 and, when detecting that the concentration of the gas to be detected is equal to or higher than a predetermined concentration (one of the abnormal states). An alarm is output to notify that the gas concentration is equal to or higher than a predetermined concentration. The gas sensor 10, the microcomputer 11, the audio output circuit (peripheral circuit) 12, and the display circuit (peripheral circuit) 13 Have. The audio output circuit 12 is a circuit for driving a speaker or a buzzer, for example, and the display circuit 13 is a circuit for driving an LED or a liquid crystal display, for example.

  The battery-operated gas alarm 1 performs an initial inspection after a reset, which will be described later. The initial check is, for example, to check whether the sound output circuit 12 and the display circuit 13 operate normally. The speaker and the buzzer are actually driven through the sound output circuit 12, and the LED and the liquid crystal are driven through the display circuit 13. Driving the display.

  The gas sensor 10 outputs a signal corresponding to the concentration of the surrounding gas to be detected. The gas sensor 10 is configured by a sensor of a semiconductor type, a contact combustion type or the like. The microcomputer 11 controls the entire alarm device 1 and includes a CPU 14, a ROM 15, and a RAM 16.

  The CPU 14 is a central processing unit that performs various processes according to a program. The ROM 15 is a read-only memory that stores a program for processing performed by the CPU 14 and the like. The RAM 16 is a readable and writable memory having a work area used in various processing steps in the CPU 14, a data storage area for storing various data, and the like.

  The CPU 14 determines whether or not the concentration of the gas to be detected is equal to or higher than a predetermined concentration based on a signal from the gas sensor 10. It controls the circuit 13 to output an alarm.

  Such a microcomputer 11 can exhibit the following functions by executing a program stored in the ROM 15. FIG. 2 is a functional block diagram of the microcomputer 11 shown in FIG. As shown in FIG. 2, the microcomputer 11 includes a voltage detection unit (first function) 11a, a voltage drop determination unit 11b, a peripheral circuit off unit (second function) 11c, a reset unit (third function) 11d. , A specific program execution unit (fourth function) 11e.

  The voltage detector 11a detects the voltage of the battery 20. The voltage detection unit 11a may detect the battery voltage when there is no load and the battery voltage when peripheral circuits such as a speaker are operating, or may detect the battery voltage by connecting a dummy resistor.

  The voltage drop determination unit 11b determines whether the battery voltage detected by the voltage detection unit 11a is equal to or lower than a predetermined voltage (for example, 2.6 V). Things. At this time, the voltage drop determination unit 11b drives the audio output circuit 12 and the display circuit 13 to notify the drop in the battery voltage by voice or display.

  When the battery voltage detected by the voltage detection unit 11a becomes equal to or lower than a specific voltage (for example, 2.4 V) lower than a predetermined voltage, the peripheral circuit off unit 11c switches the audio output circuit 12 and the display circuit 13 that are peripheral circuits. It is something that turns off. Further, when the battery voltage becomes equal to or lower than the specific voltage, the peripheral circuit off unit 11c also turns off the drive circuit of the gas sensor 10 which is a peripheral circuit. The peripheral circuit off section 11c is not limited to all peripheral circuits, but may be any as long as it turns off at least one of the peripheral circuits.

  Here, the voltage detection unit 11 a according to the present embodiment is one function of the microcomputer 11. That is, in the battery-operated gas alarm 1 according to the present embodiment, the voltage detection IC is not provided outside the microcomputer 11, but the voltage detection unit 11 a is mounted as one function of the microcomputer 11. However, the present invention is not limited to this, and a functional unit equivalent to the voltage detection unit 11a such as a voltage detection IC may be provided outside the microcomputer 11. Note that the voltage detection unit 11a (or equivalent functional unit) can detect the battery voltage as long as the battery voltage is equal to or higher than a voltage value (for example, 1.8 V) slightly below a specified voltage (for example, 2.0 V) described later. Has become.

  Further, the peripheral circuit off unit 11c according to the present embodiment also has one function of the microcomputer 11, but is not limited to this, and an equivalent configuration may be provided outside the microcomputer 11. For example, it is assumed that the power supply of the peripheral circuit is made by a DC / DC converter. A signal from a comparator is input to a standby terminal of the DC / DC converter. The battery voltage is monitored by the comparator, and when the battery voltage becomes equal to or lower than the specific voltage, the DC / DC converter enters a standby state by a signal input from the comparator to the standby terminal. As a result, power supply to the peripheral circuit is stopped, and the peripheral circuit can be turned off.

  The reset unit 11d resets the microcomputer 11 when the battery voltage is equal to or lower than a reset voltage (for example, 1.5 V) lower than the specific voltage. The microcomputer 11 has a reset circuit that generates a reset signal when the battery voltage reaches the reset voltage or lower. When the reset circuit generates a reset signal, the microcomputer 11 is reset.

  Here, the reset unit 11d according to the present embodiment is one function of the microcomputer 11. That is, in the battery-operated gas alarm 1 according to the present embodiment, the reset IC is not provided outside the microcomputer 11, but the reset unit 11 d is mounted as one function of the microcomputer 11. However, the present invention is not limited thereto, and a functional unit equivalent to the reset unit 11d for resetting the microcomputer 11 such as a reset IC may be provided outside the microcomputer 11.

  The specific program execution unit 11e executes a specific program when the battery voltage detected by the voltage detection unit 11a is lower than a specific voltage and equal to or higher than a specified voltage (for example, 2.0 V) exceeding a reset voltage. When the battery voltage becomes lower than the specified voltage, execution of a specific program is prohibited. Here, when the battery voltage is equal to or higher than the specified voltage, it can be said that the battery voltage may be restored. For this reason, the specific program execution unit 11e counts a specific program (for example, a program for maintaining a state at the time of turning off peripheral circuits, a gas detection timing of a gas alarm device, or the like) when the voltage is equal to or higher than a specified voltage at which power may be restored. A sampling timer of the sampling timer to be executed), and prepare for power recovery. In this embodiment, the specific program does not include the operation program of the voltage detection unit 11a, and the voltage detection unit 11a detects the battery voltage unless the battery voltage becomes 1.8 V or less, for example. be able to.

  FIG. 3 is a timing chart showing a voltage state of the battery-operated gas alarm 1 according to the present embodiment. As shown in FIG. 3, it is assumed that the battery voltage at time 0 slightly exceeds a predetermined voltage. Then, it is assumed that the load is driven at time t1 for some reason. As a result, the battery voltage decreases. Then, at time t2, the battery voltage becomes equal to or lower than the specific voltage. Here, in the battery-operated gas alarm 1 according to the present embodiment, a reset voltage lower than the specific voltage is set. Therefore, the microcomputer 11 is not reset at the time t2.

  At time t2, the peripheral circuit off unit 11c stops the peripheral circuits. Therefore, the electrical connection between the load driven at time t1 and the battery 20 is also cut off. Therefore, at time t3, the battery voltage starts to increase. Then, at time t4, the battery voltage exceeds the predetermined voltage. The peripheral circuit turned off at time t2 is turned on at time t4 when the battery voltage becomes equal to or higher than the restoration voltage (for example, 2.6 V, which is the same as the predetermined voltage in the present embodiment).

  As described above, in the present embodiment, even if the battery voltage becomes equal to or lower than the specific voltage, the microcomputer 11 is not reset. Therefore, the initial check is performed after the power is restored, and the battery voltage does not drop again, thereby preventing the reset operation from being repeated. Although the battery voltage becomes equal to or lower than the specific voltage at the time t2, the specific program is continuously executed because the battery voltage is maintained at or above the specified voltage.

  Thereafter, at time t5, for example, when the battery-operated gas alarm device 1 gets wet with water, it is assumed that the battery voltage starts to drop sharply. Then, it is assumed that at time t6, the battery voltage is rapidly reduced due to a temporary short circuit and becomes lower than the reset voltage. In this case, the reset unit 11d of the microcomputer 11 resets itself.

  Thereafter, the battery voltage recovers due to the elimination of the water wetness, and becomes equal to or higher than the specified voltage at time t7 and equal to or higher than the specific voltage at time t8. Here, when the microcomputer 11 is reset, the voltage of the microcomputer 11 becomes lower than the specified voltage, so that the execution of the specific program is also prohibited. This prohibited specific program is not executed when the voltage becomes equal to or higher than the specified voltage at time t7, and is executed when the voltage becomes equal to or higher than the restoration voltage at time t8. That is, the microcomputer 11 keeps prohibiting the execution of the specific program until the voltage becomes equal to or higher than the restoration voltage at the time t8. Accordingly, it is possible to prevent a situation in which a specific program is executed at a relatively early stage after the reset, the battery voltage drops again, and the reset operation is repeated.

  Although the description has been made above that the execution timing of the specific program is time t8, the operation of the peripheral circuit also starts at time t8. That is, the turned off peripheral circuit is turned on when the battery voltage becomes equal to or higher than the restoration voltage as in the case of the time t4.

  Thus, according to the battery-operated gas alarm 1 according to the present embodiment, the microcomputer 11 has a function of turning off at least one of the peripheral circuits when the detected battery voltage is equal to or lower than the specific voltage, It has a function of resetting itself when the battery voltage is equal to or lower than a reset voltage lower than a specific voltage. For this reason, even when the battery voltage exceeds the specific voltage and becomes lower than the specific voltage due to, for example, driving of the load, the microcomputer 11 is not reset unless the voltage becomes lower than the reset voltage. If the reset is not performed, the initial inspection is not performed, and the battery voltage does not drop again due to the driving of the load at the time of the initial inspection. Therefore, when the microcomputer 11 is reset based on the detected battery voltage, repetition of the reset operation can be prevented.

  Further, the microcomputer 11 executes a specific program when the battery voltage is lower than the specific voltage and is equal to or higher than a specified voltage exceeding the reset voltage, and does not execute the specific program when the voltage becomes lower than the specified voltage. For this reason, when the battery voltage has not reached the reset voltage and is equal to or higher than the specified voltage at which there is a possibility of power recovery, a specific program (for example, a program for holding the state at the time of turning off peripheral circuits, a gas detection And the like, a sampling timer of a sampling timer for measuring the time and the like is executed, and the power supply can be prepared in case of power recovery.

  In addition, when the self is reset, the execution of the specific program is continued to be prohibited until the battery voltage becomes equal to or higher than the return voltage exceeding the specific voltage, so that the specific program is executed relatively early after the reset, It is possible to prevent a situation in which the battery voltage drops again and the reset operation is repeated.

  As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and may be modified without departing from the spirit of the present invention. May be combined.

  For example, in the above embodiment, the voltage detection unit 11a can detect the battery voltage as long as the battery voltage is equal to or higher than a voltage value (for example, 1.8 V) slightly lower than a specified voltage (for example, 2.0 V). The slightly lower voltage value may be a reset voltage (for example, 1.5 V).

1: battery-operated gas alarm 10: gas sensor 11: microcomputer 11a: voltage detector (first function)
11b: Voltage drop determining section 11c: Peripheral circuit off section (second function)
11d: reset unit (third function)
11e: Specific program execution unit (fourth function)
12: Audio output circuit (peripheral circuit)
13: Display circuit (peripheral circuit)
14: CPU
15: ROM
16: RAM
20: Battery

Claims (3)

A battery-operated alarm device that is driven by the power of the battery, outputs an alarm when an abnormal condition is detected by a function mounted on the microcomputer, notifies the abnormal condition, and performs an initial inspection after resetting the microcomputer. hand,
A first function of detecting a battery voltage, a function of notifying that the battery voltage detected by the first function is equal to or lower than a predetermined voltage, and a specification that the battery voltage detected by the first function is lower than the predetermined voltage. A second function for turning off at least one of the peripheral circuits when the voltage is equal to or lower than a voltage, and a third function for resetting the microcomputer when the battery voltage is equal to or lower than a reset voltage lower than the specific voltage. Battery powered alarm. A battery-operated alarm that is driven by the power of the battery, outputs an alarm when an abnormal state is detected by a function mounted on the microcomputer, notifies the abnormal state, and performs an initial inspection after resetting the microcomputer. hand,
A first function for detecting a battery voltage, a second function for turning off at least one of peripheral circuits when the battery voltage detected by the first function is equal to or lower than a specific voltage, and a reset voltage equal to or lower than a reset voltage lower than the specific voltage A third function of resetting the microcomputer if the battery voltage detected by the first function is less than the specific voltage and equal to or higher than a specified voltage exceeding the reset voltage. If you are running a particular program, battery voltage, a fourth function to prohibit the execution of the specific program is a voltage lower than the specified voltage
A battery-operated alarm device characterized by the above-mentioned . When the microcomputer is reset by the third function, the execution of the specific program prohibited by the fourth function is performed until the battery voltage detected by the first function becomes equal to or higher than the return voltage exceeding the specific voltage. The battery-operated alarm according to claim 2, wherein the battery-operated alarm continues to be prohibited.

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