JP2017062658A - Battery type alarm - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery type alarm capable of preventing repetition of reset operation when resetting a microcomputer based on a detected battery voltage.SOLUTION: A battery type alarm is driven by battery power, outputs an alarm in detection of an abnormal state by a function mounted on a microcomputer 11 to report the abnormal state, and executes an initial inspection after resetting the microcomputer 11. The battery type alarm includes: a voltage detection part 11a for detecting a battery voltage; a peripheral circuit off part 11c for turning off at least one of peripheral circuits when the battery voltage detected by the voltage detection part 11a is equal to or less than a specific voltage; and a resetting part 11d for resetting the microcomputer 11 when the battery voltage is equal to or less than a reset voltage smaller than the specific voltage.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a battery-type alarm device.

  Conventionally, a battery-type alarm device capable of detecting a battery voltage has been proposed. This battery-powered alarm is configured to issue a warning when the battery voltage drops. When the battery voltage drops, the battery voltage drop warning sound (voice message “Battery is dead” and electronic sound “Pip” sound is issued. ) To inform the user of a decrease in battery voltage (see, for example, Patent Document 1).

  In addition, a battery-type alarm device having a reset function for 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 microcomputer abnormality or the like can be eliminated (see, for example, Patent Document 2).

JP 2013-178649 A JP2012-198752A

  Here, when the load is driven in the battery-type alarm device, the battery voltage is lowered. For this reason, for example, when the battery voltage becomes equal to or lower than a predetermined voltage and the above warning sound is generated (that is, when the load is driven) as in Patent Document 1, or when the battery voltage slightly exceeds the predetermined voltage (for example, When the load is driven by (abnormality detection), the battery voltage further decreases. Further, in an alarm device having a reset function like the battery-type alarm device described in Patent Document 2, for example, a microcomputer is used at the timing when the battery voltage further decreases (when the battery voltage falls below a specific voltage lower than a predetermined voltage). It is conceivable to reset.

  However, when resetting at such timing, the following problems occur. FIG. 4 is a timing chart showing a voltage state of the battery type alarm device according to the comparative example.

  First, it is assumed that the battery voltage slightly exceeds the predetermined voltage at time 0. Assume that the load is driven for some reason at time t41. Thereby, a battery voltage will fall. When the battery voltage becomes equal to or lower than the specific voltage at time t42, the microcomputer is reset. In addition, the peripheral circuit is stopped together with the resetting of the microcomputer, and the electrical connection relationship between the load driven at time t41 and the battery is cut off. For this reason, the battery voltage starts to rise at time t43. Then, at time t44, the battery voltage exceeds the specific voltage.

  When the voltage exceeds a specific voltage, the microcomputer starts to operate and the peripheral circuits also operate. Here, the battery-type alarm device is often subjected to an initial check, and various loads operate as an initial check immediately after the microcomputer is started. For this reason, although the battery voltage is doubled to a state where it slightly exceeds the predetermined voltage at time t45, it starts to decrease again at time t46 due to the driving of the load in the initial inspection.

  Thereafter, since the battery voltage becomes equal to or lower than the specific voltage at time t47, the microcomputer is reset. As the microcomputer is reset, the peripheral circuit is also stopped, and the electrical connection relationship between the load and the battery driven in the initial inspection is cut off. For this reason, the battery voltage starts to rise at time t48. Then, at time t49, the battery voltage exceeds the specific voltage. Thereafter, the above operation is repeated.

  As described above, when the technology of the battery-type alarm device described in Patent Document 1 and the technology of the battery-type alarm device described in Patent Document 2 are combined, the reset operation is repeated. In particular, when a sound such as “beep” is output in the initial inspection, a sound of “beep” is repeatedly generated along with repeated reset.

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

  The battery type alarm device of the present invention is driven by battery power, outputs an alarm when an abnormal state is detected by a function installed in the microcomputer, notifies the abnormal state, and performs initial inspection after resetting the microcomputer. A first function for detecting battery voltage, a second function for turning off at least one of the peripheral circuits when the battery voltage detected by the first function is equal to or lower than a specific voltage, And 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.

  According to this battery type alarm device, the microcomputer 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, and the microcomputer when the battery voltage is equal to or lower than the reset voltage lower than the specific voltage. Has a function of resetting. For this reason, even if the battery voltage exceeds the specific voltage and becomes lower than the specific voltage by driving the load, for example, the microcomputer is not reset unless it becomes lower than the reset voltage. Further, when the reset is not performed, the initial inspection is not performed, and the battery voltage is not lowered again by driving the load at the initial inspection. Therefore, when the microcomputer is reset based on the detected battery voltage, it is possible to prevent the reset operation from being repeated.

  In the battery-type alarm device of the present invention, when the battery voltage detected by the first function is less than the specified voltage and more than a specified voltage exceeding the reset voltage, a specific program is executed by the microcomputer. It is preferable to further include a fourth function that prohibits execution of a specific program when the battery voltage is lower than the specified voltage.

  According to this battery type alarm device, when the battery voltage is less than the specified voltage and above the specified voltage exceeding the reset voltage, a specific program is executed by the microcomputer. Do not run the program. For this reason, when the battery voltage has not reached the reset voltage and is higher than a specified voltage that can be restored, a specific program (for example, a program that maintains the state at the off time of the peripheral circuit, gas detection timing of the gas alarm, etc. A sampling timer clocking program that counts the clock time, etc.) can be executed in preparation for power recovery.

  In the battery-type alarm device according to 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 to continue prohibition until the return voltage exceeds the specific voltage.

  According to this battery-powered alarm device, when a microcomputer is reset, the execution of a specific program is prohibited until the battery voltage exceeds the return voltage exceeding the specific voltage. This prevents the situation where the battery voltage is lowered again and the reset operation is repeated.

  ADVANTAGE OF THE INVENTION According to this invention, when resetting a microcomputer based on the detected battery voltage, the battery-type alarm device which can prevent repetition of reset operation can be provided.

It is a block diagram which shows the battery-type alarm device which concerns on embodiment of this invention. It is a functional block diagram of the microcomputer shown in FIG. It is a timing chart which shows the voltage state of the battery-type gas alarm device which concerns on this embodiment. It is a timing chart which shows the voltage state of the battery-type alarm device which concerns on a comparative example.

  Hereinafter, the present invention will be described according to 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. Further, in the embodiment described below, there is a part where illustration or description of a part of the configuration is omitted, but details of the omitted technology are within a range in which there is no contradiction with the contents described below. Needless to say, known or well-known techniques are applied as appropriate.

  FIG. 1 is a configuration diagram illustrating a battery-type alarm device according to an embodiment of the present invention. In the following, a battery-type gas alarm will be described as an example of a battery-type alarm. However, the battery-type alarm is not limited to a battery-type gas alarm, but other alarms such as battery-type fire, CO, and human feelings. It may be a battery type alarm device combining the functions of two or more alarm devices.

  As shown in the figure, when the battery-type gas alarm device 1 is driven by the power of the battery 20 and detects that the concentration of the gas to be detected is equal to or higher than a predetermined concentration (one of 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 are provided. I have. The audio output circuit 12 is a circuit that drives a speaker or a buzzer, for example, and the display circuit 13 is a circuit that drives an LED or a liquid crystal display, for example.

  Moreover, the battery-type gas alarm device 1 performs an initial inspection after a reset described later. The initial check is to check whether the audio output circuit 12 and the display circuit 13 operate normally, for example, by actually driving a speaker or a buzzer through the audio output circuit 12, or through an LED or liquid crystal through the display circuit 13. Drive the display.

  The gas sensor 10 outputs a signal corresponding to the concentration of the surrounding gas to be detected. The gas sensor 10 includes a semiconductor type sensor, a catalytic combustion type sensor, 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. The RAM 16 is a readable / writable memory having a work area used in various processes in the CPU 14 and a data storage area for storing various data.

  The CPU 14 determines whether 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. When the CPU 14 determines that the concentration is higher than the predetermined concentration, the audio output circuit 12 and the display are displayed. The circuit 13 is controlled 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, and a reset unit (third function) 11d. And a specific program execution unit (fourth function) 11e.

  The voltage detector 11 a detects the voltage of the battery 20. The voltage detection unit 11a may detect the battery voltage with no load and the battery voltage during the operation of a peripheral circuit such as a speaker, or may detect the battery voltage by connecting a dummy resistor.

  The voltage drop determination unit 11b determines whether or not the battery voltage detected by the voltage detection unit 11a is equal to or lower than a predetermined voltage (for example, 2.6 V), and notifies that when it determines that the voltage is equal to or lower than the predetermined voltage. Is. At this time, the voltage drop determination unit 11b drives the voice output circuit 12 and the display circuit 13 to notify the battery voltage drop by voice or display.

  When the battery voltage detected by the voltage detector 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 turns off the audio output circuit 12 and the display circuit 13 that are peripheral circuits. It is to turn off. Furthermore, the peripheral circuit off unit 11c also turns off the driving circuit of the gas sensor 10 that is a peripheral circuit when the battery voltage becomes equal to or lower than the specific voltage. Note that the peripheral circuit off unit 11c is not limited to all of the peripheral circuits, and may be any one that turns off at least one of the peripheral circuits.

  Here, the voltage detection unit 11 a according to the present embodiment has one function of the microcomputer 11. That is, the battery-type gas alarm device 1 according to the present embodiment is not configured such that the voltage detection IC is 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 11 a such as a voltage detection IC may be provided outside the microcomputer 11. The voltage detection unit 11a (or an equivalent functional unit) can detect the battery voltage as long as the battery voltage is a voltage value (for example, 1.8V) slightly lower than a specified voltage (for example, 2.0V) described later. It has become.

  Furthermore, the peripheral circuit off unit 11c according to the present embodiment also has one function of the microcomputer 11. However, the present invention 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 for 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 the standby state by a signal input from the comparator to the standby terminal. Thereby, the 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 includes a reset circuit that generates a reset signal when the battery voltage reaches a reset voltage or less. When the reset circuit generates a reset signal, the microcomputer 11 is reset.

  Here, the reset unit 11 d according to the present embodiment has one function of the microcomputer 11. That is, the battery-type gas alarm device 1 according to the present embodiment is not configured such that the reset IC is 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 to this, and a functional unit equivalent to the reset unit 11 d 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 equal to or higher than a specified voltage (eg, 2.0 V) that is less than the specific voltage and exceeds the reset voltage. When the battery voltage is lower than the specified voltage, the 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 there is a possibility that the battery voltage is restored. For this reason, the specific program execution unit 11e measures a specific program (for example, a program for holding a state at the time when the peripheral circuit is turned off, a gas detection timing of the gas alarm device, etc.) when the voltage is higher than a specified voltage with a possibility of power recovery. (Sampling timer clocking program, etc.) to be executed in preparation for power recovery. In the present 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 the voltage state of the battery-type gas alarm device 1 according to the present embodiment. As shown in FIG. 3, it is assumed that the battery voltage slightly exceeds the predetermined voltage at time 0. Assume that the load is driven for some reason at time t1. Thereby, a battery voltage will fall. Then, at time t2, the battery voltage becomes equal to or lower than the specific voltage. Here, in the battery-type gas alarm device 1 according to the present embodiment, a reset voltage lower than the specific voltage is set. For this reason, the microcomputer 11 is not reset at time t2.

  At time t2, the peripheral circuit off unit 11c stops the peripheral circuit. For this reason, the electrical connection relationship between the load driven at time t1 and the battery 20 is also cut off. For this reason, the battery voltage starts to rise at time t3. 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 recovery voltage (for example, 2.6 V and the same predetermined voltage in this embodiment).

  Thus, in this embodiment, even if the battery voltage becomes a specific voltage or less, the microcomputer 11 is not reset. Therefore, the initial inspection is performed after the power recovery and the battery voltage does not drop again, and the reset operation is prevented from being repeated. In addition, although battery voltage becomes below a specific voltage at said time t2, since a battery voltage maintains more than a regulation voltage, a specific program will continue to be executed.

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

  Thereafter, when the water wetting is eliminated, the battery voltage recovers, becomes equal to or higher than the specified voltage at time t7, and becomes equal to or higher than the recovery voltage exceeding the specific voltage at time t8. Here, since the microcomputer 11 becomes less than the specified voltage when the microcomputer 11 is reset, execution of a specific program is also prohibited. The prohibited specific program is not executed when the voltage exceeds the specified voltage at time t7, and is executed when the voltage exceeds the power recovery voltage at time t8. In other words, the microcomputer 11 continues to prohibit execution of a specific program until the voltage becomes equal to or higher than the power recovery voltage at time t8. As a result, it is possible to prevent a situation where a specific program is executed at a relatively early stage after reset and the battery voltage decreases again, leading to repetition of the reset operation.

  In the above description, the execution timing of the specific program is described as being time t8. However, the operation of the peripheral circuit is also started at time t8. That is, the peripheral circuit that has been turned off is turned on when the battery voltage becomes equal to or higher than the power recovery voltage, similarly to time t4.

  Thus, according to the battery-type gas alarm device 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 if the battery voltage exceeds the specific voltage and becomes equal to or lower than the specific voltage by driving the load, for example, the microcomputer 11 is not reset unless the voltage is equal to or lower than the reset voltage. Further, when the reset is not performed, the initial inspection is not performed, and the battery voltage is not lowered again by driving the load at the initial inspection. Accordingly, when the microcomputer 11 is reset based on the detected battery voltage, it is possible to prevent the reset operation from being repeated.

  The microcomputer 11 executes a specific program when the battery voltage is less than the specified voltage and is equal to or higher than the specified voltage exceeding the reset voltage, and does not execute the specified program when the voltage is less than the specified voltage. For this reason, when the battery voltage has not reached the reset voltage and is higher than the specified voltage with the possibility of power recovery, a specific program (for example, a program for holding the state at the off time of the peripheral circuit, gas detection timing of the gas alarm) Etc.) can be prepared in preparation for power recovery.

  In addition, in order to continue to prohibit the execution of a specific program when the self is reset until the battery voltage exceeds the return voltage exceeding the specific voltage, the specific program is executed at a relatively early stage after the reset, It is possible to prevent a situation in which the battery voltage is lowered again and the reset operation is repeated.

  As described above, the present invention has been described based on the embodiments, but the present invention is not limited to the above-described embodiments, and may be modified without departing from the spirit of the present invention, and may be appropriately changed within a possible range. These techniques 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 a voltage value (e.g., 1.8V) slightly lower than a specified voltage (e.g., 2.0V). The slightly lower voltage value may be a reset voltage (for example, 1.5 V).

1: Battery type gas alarm device 10: Gas sensor 11: Microcomputer 11a: Voltage detector (first function)
11b: Voltage drop determination unit 11c: Peripheral circuit off unit (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-type alarm device that is driven by battery power, outputs an alarm when an abnormal state is detected by a function installed in the microcomputer, notifies the abnormal state, and performs an initial inspection after resetting the microcomputer. And
A first function for detecting a battery voltage; a second function for turning off at least one of the peripheral circuits when the battery voltage detected by the first function is equal to or lower than a specific voltage; and a reset voltage having a battery voltage lower than the specific voltage A battery-powered alarm device having a third function of resetting the microcomputer when: When the battery voltage detected by the first function is less than the specified voltage and not less than a specified voltage exceeding the reset voltage, the microcomputer executes a specific program, and the battery voltage is the specified voltage. The battery-powered alarm device according to claim 1, further comprising a fourth function for prohibiting execution of a specific program when the voltage is lower than the voltage. 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-type alarm device according to claim 2, wherein the battery-type alarm device is continuously prohibited.

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