JP2011130539A - Radio notification device and method of detecting reduction in battery capacity for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio notification device for accurately measuring a voltage of a battery at packet transmission, and for detecting the voltage of the battery for each packet to more accurately detect the minimum voltage. <P>SOLUTION: The radio notification device 1 includes a button 11 for packet transmission, the battery 12 for supplying power, a storage unit 13 for storing a threshold of the voltage of the battery for battery exhaustion detection, a radio unit 14 for transmitting packets, and a control unit 15 for transmitting packets via the radio unit 14 when the button 11 is pressed down and then comparing a voltage of the battery 12 with the threshold stored in the storage unit 13 for each packet to determining whether or not the battery has run out. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radio notification device and a battery capacity reduction detection method thereof, and particularly to a radio notification device and a battery thereof for notifying a center via a public line or the like when a physical condition change or accident occurs in a user. The present invention relates to a capacity drop detection method.

  As a power source for a radio notification device related to the present invention, for example, a portable radio notification device, a small and light battery such as a lithium battery is generally used. FIG. 10 is a voltage vs. time characteristic diagram of an example of a lithium battery used in a radio notification apparatus related to the present invention, and FIG. 11 is a voltage vs. battery capacity characteristic diagram of an example of the lithium battery.

  As shown in FIG. 10, the lithium battery has a property that the voltage sharply decreases when the consumption current is relatively large (heavy load period). Therefore, there is a possibility that the rated voltage of an IC (Integrated Circuit) or the like is divided during wireless use even if the standby voltage is not a problem.

  FIG. 11 shows a discharge curve when a load is continuously applied to the lithium battery. As shown in the figure, even when the same load is applied, the battery voltage and the battery capacity (remaining battery capacity) have different characteristics depending on the ambient temperature environment. If the same threshold value is used at both high and low temperatures, as shown by the battery alarm voltage (dashed line) in the figure, a battery alarm is displayed indicating that the battery has run out at low temperatures even though the battery capacity has not yet been used up. End up. On the other hand, when the temperature is high, the remaining capacity of the battery after reaching the alarm voltage is smaller than when the temperature is low, and the remaining capacity until battery replacement is insufficient.

  On the other hand, in the case of a radio notification device that notifies the center of a change in physical condition or accident to the user via a public line, etc. The device must be kept ready for use.

  As a countermeasure, a method to provide a circuit to monitor the battery voltage and notify the center when the voltage falls below an arbitrary voltage can be easily considered. However, in the case of a lithium battery, the voltage is measured accurately because of the above-mentioned characteristics. There is a possibility that the battery capacity may be considered to be reduced even though the battery capacity cannot be achieved.

  As an example of the solution, a method has been proposed in which a capacitor is disposed in the voltage detection circuit to store electric charges, thereby eliminating fluctuations in voltage drop in the voltage detection circuit during wireless use and performing battery exhaustion determination ( For example, see Patent Document 1).

  As another example of a solution, a method has been proposed in which the time until the voltage is restored from the point of voltage drop is measured to check the battery capacity (see, for example, Patent Document 2).

  As another example of a solution, a circuit that discharges the secondary battery with a large current, a circuit that measures the terminal voltage of the secondary battery after a certain period of time has elapsed from the start of operation, and a voltage drop amount is calculated from the terminal voltage And a circuit that compares the calculated voltage drop amount with a reference value, and a method of stopping discharge when the voltage drop amount exceeds the reference value has been proposed (for example, see Patent Document 3). .

  As another example of a solution, a circuit in which a first thermistor and a first resistor are connected in parallel and a circuit in which a second thermistor and a second resistor are connected in series are connected in series, and lithium ions are connected to both ends thereof. A correction circuit that applies an output voltage of a secondary battery and corrects and detects the end-of-discharge voltage with temperature has been proposed (see, for example, Patent Document 4).

  As another example of the solution, the monochromatic light is irradiated on the electrode surface of the lithium battery, the reflected light is guided to the light receiving unit, the reflected absorbance is calculated, and the previously stored reflected absorbance and battery capacity are calculated. There has been proposed a method for measuring the remaining capacity of a lithium battery that compares the relationship and calculates the battery capacity (see, for example, Patent Document 5).

  As another example of the solution, the switching element is periodically driven for a predetermined time to pass an overcurrent larger than the normal load current from the battery. A battery life detection device for discrimination has been proposed (see, for example, Patent Document 6).

  As another example of the solution, a terminal voltage of the battery is detected by connecting a first load to the lithium battery, and then a terminal voltage is detected by connecting a second load smaller than the first load to the lithium battery. And a battery capacity decrease detection device that detects the first and second capacity decrease states of the battery based on respective detection voltages has been proposed (see, for example, Patent Document 7).

  In addition, as an example of another solution, based on each sampling data of the terminal voltage and current of the lithium battery, correct the current dependency of the electromotive force of the lithium battery according to the lithium diffusion concentration gradient in the electrode of the lithium battery, A method for measuring the remaining capacity of a lithium battery has been proposed in which the open circuit voltage of the lithium battery is obtained from the correction result and the remaining capacity of the lithium battery is measured based on the open circuit voltage (see, for example, Patent Document 8).

JP 2001-228221 A JP 09-247865 A JP 07-037621 A Japanese Patent No. 3851100 JP 2000-131405 A Japanese Patent Laid-Open No. 01-127983 Japanese Patent Laid-Open No. 04-346072 JP-A-11-204149

  However, the invention described in Patent Document 1 has a drawback in that it is impossible to know how many volts the voltage dropped at the time of heavy load because it is determined by looking at the standby voltage. Therefore, there is a possibility that the dropped voltage is lower than the rated voltage of an element such as an IC. Even if it is desired to make a report, the IC or the like does not operate, and there is a possibility that an important report cannot be made.

  In addition, since the voltage stored in the capacitor is consumed by leakage current and the input resistance of the detection circuit, current consumption is always generated even during standby, reducing the battery capacity and shortening the life of the device. is there.

  In the invention described in Patent Document 2, measurement must be performed until the battery voltage is restored, and if it is long, monitoring must be performed for several minutes. For this reason, the current consumption increases when the wireless communication is not performed, so that there is a disadvantage that the battery life is shortened.

  Further, since the battery exhaustion alarm is determined based on the time until recovery, it is not observed how many volts the battery voltage has actually dropped. FIG. 12 is a terminal voltage versus time characteristic diagram of an example of this type of battery. As an example, as shown in the figure, it is assumed that the user presses the button again when the battery voltage is in the process of recovery. In this case, the battery voltage drops sharply during the recovery.

  Therefore, if the minimum voltage is not measured, there is a drawback in that it is impossible to detect that there is a risk that this minimum voltage falls below the rating of an element such as an IC. Further, since the voltage after restoration is lower than the voltage to be restored when the normal one-time button is pressed, there is a possibility that it is determined that the battery is exhausted despite the remaining battery level.

  Moreover, in invention of patent document 3, it is the structure which measures the terminal voltage of a secondary battery only once at the time of heavy load. On the other hand, the secondary battery has the characteristics that the heavy load state continues for a certain time and the capacity decreases as the current is consumed, and the terminal voltage also decreases. Therefore, the present invention has a drawback that it is impossible to detect a change in the terminal voltage when the heavy load state continues for a certain time.

  Further, in the invention described in Patent Document 4, it is possible to read a voltage value that is corrected by temperature. However, an actual lithium battery has a characteristic that the voltage curve near the battery capacity is different depending on the temperature. Therefore, in the present invention, it is considered difficult to set a value for efficiently extracting the remaining battery level at both low sounds and high temperatures.

  In the present invention, the relative value of the battery terminal voltage is corrected according to the ambient temperature, and the corrected value is compared with a fixed threshold value. That is, the terminal voltage changes according to the ambient temperature and the threshold value is fixed, which is completely opposite to the present invention. For this reason, in the invention described in Patent Document 4, it is necessary to provide two thermistor circuits for calculating the relative value of the battery terminal voltage according to the ambient temperature, and there is a disadvantage that the number of parts increases and the cost increases.

  Further, other inventions described in Patent Documents 5 to 8 do not describe the characteristic configuration of the present invention in which the voltage of the battery is compared with the threshold value for each packet.

  Accordingly, an object of the present invention is to provide a wireless notification device capable of accurately measuring the voltage of a battery at the time of packet transmission, and more accurately detecting the minimum voltage by detecting the voltage of the battery for each packet. It is another object of the present invention to provide a battery capacity drop detection method.

  In order to solve the above-mentioned problem, a radio notification device according to the present invention transmits a packet, a button for packet transmission, a battery for power supply, a storage unit for storing a battery voltage threshold for battery exhaustion detection, and a packet. A wireless unit that transmits a packet via the wireless unit when the button is pressed, and compares the battery voltage with a threshold stored in the storage unit for each packet to determine whether the battery is dead It is characterized by including.

  The battery capacity drop detection method according to the present invention includes a packet transmission button, a battery for power supply, a storage unit for storing a battery voltage threshold for battery exhaustion detection, and a radio unit for transmitting a packet. A battery capacity drop detection method in a wireless notification device including a control unit, wherein the control unit transmits a packet via the wireless unit when the button is pressed, and sets the battery voltage for each packet. Compared with the threshold value stored in the storage unit, it is determined that the battery has run out.

  The battery capacity drop detection method program according to the present invention includes a packet transmission button, a battery for power supply, a storage unit for storing a battery voltage threshold for battery exhaustion detection, and a radio for transmitting packets. A battery capacity drop detection method program in a wireless notification device including a control unit and a control unit, wherein the control unit transmits a packet via the wireless unit when the button is pressed, and The battery voltage is compared with a threshold value stored in the storage unit to determine whether the battery has run out.

  According to the present invention, it is possible to accurately measure the battery voltage at the time of packet transmission, and more accurately detect the minimum voltage by detecting the battery voltage for each packet.

It is a schematic diagram which shows the operation | movement principle of the radio notification apparatus which concerns on this invention. It is a block diagram of 1st Embodiment of the portable radio | wireless alerting device which concerns on this invention. It is a figure which shows an example of the battery voltage versus time characteristic of the radio reporting device according to the present invention. It is a voltage versus time characteristic view showing an example of a relation between a detected value of battery voltage and noise. It is a voltage vs. battery capacity | capacitance characteristic view which shows an example of the relationship between a battery voltage and battery capacity. It is a flowchart which shows operation | movement of 1st Embodiment of the radio notification apparatus which concerns on this invention. It is a flowchart which shows operation | movement of 2nd Embodiment of the radio notification apparatus which concerns on this invention. It is a block diagram of 3rd Embodiment of the portable radio | wireless alerting device which concerns on this invention. It is a schematic diagram which shows an example of operation | movement of 3rd Embodiment. It is a voltage vs. time characteristic figure of an example of the lithium battery used for the radio notification apparatus relevant to this invention. It is a voltage versus battery capacity characteristic figure of an example of the lithium battery. It is a terminal voltage vs. time characteristic view of an example of this type of battery.

  First, the operation principle of the present invention will be described before the description of the embodiment. FIG. 1 is a schematic diagram showing the operating principle of a radio notification device according to the present invention. Referring to FIG. 1, the wireless notification device 1 according to the present invention includes a button 11, a battery 12, a storage unit 13, a wireless unit 14, and a control unit 15.

  The button 11 is pressed when performing packet transmission. The battery 12 supplies power to each part. The storage unit 13 stores a battery voltage threshold value for battery exhaustion detection. The wireless unit 14 transmits a packet. When the button 11 is pressed, the control unit 15 transmits a packet via the wireless unit 14, and compares the voltage of the battery 12 with the threshold stored in the storage unit 13 for each packet to determine whether the battery is dead.

  That is, according to the present invention, the voltage of the battery 12 is measured at the time of heavy load at the time of packet transmission, and the value is compared with a threshold value to determine whether the battery is dead. Therefore, the battery voltage at the time of packet transmission is accurately measured. It becomes possible to do. In addition, since the battery exhaustion determination is not performed during standby, current consumption during standby can be suppressed. Furthermore, since the battery exhaustion is determined for each packet during packet transmission, it is possible to detect a change in terminal voltage when the packet transmission state continues for a certain period of time.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, the first embodiment will be described. FIG. 2 is a configuration diagram of the first embodiment of the portable radio notification device according to the present invention. In addition, the same number is attached | subjected to the component similar to FIG. 1, and the description is abbreviate | omitted.

  In the figure, a portable device is displayed as an example of the wireless notification device. However, the present invention is not limited to this, and it is also possible to apply the present invention to a fixed wireless notification device. Referring to the figure, a portable radio notification device 2 according to the present invention includes a battery 12, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) 16, a temperature detection unit 17, a button 11, a battery low alarm LED (Light (Emitting Diode) 18, a wireless unit 14, and a control unit 15.

  The control unit 15 includes an A / D (Analog to Digital) conversion unit 19 and a storage unit 13. A configuration in which the A / D conversion unit 19 and the storage unit 13 are provided separately from the control unit 15 and the control unit 15 controls the A / D conversion unit 19 and the storage unit 13 is also possible.

  The battery 12 is a lithium battery as an example. The present invention is directed to a battery such as a lithium battery whose voltage changes sharply under heavy load. Therefore, the present invention can be applied to any battery other than the lithium battery as long as the voltage changes sharply under heavy load. The battery 12 supplies power to each part in the portable radio notification device 2.

  The MOSFET 16 is used as a switch for on / off control. However, the present invention is not limited to the MOSFET 16, and the present invention can be applied to any switch that can cut off the current when turned off.

  The temperature detector 17 detects the temperature around the battery 12. The temperature detection unit 17 is well known to those skilled in the art and is not directly related to the present invention, so that the detailed description of the configuration is omitted. The button 11 is pressed when transmitting a packet. The battery exhaustion alarm LED 18 displays an alarm when the battery is exhausted (notifies a decrease in battery life), and blinks or lights the LED when the battery is exhausted. The wireless unit 14 transmits a packet.

  The A / D converter 19 converts analog data into digital data. The storage unit 13 stores in advance a plurality of patterns of the ambient temperature of the battery 12 and the threshold value of the battery exhaustion alarm corresponding to the ambient temperature. The control unit 15 controls the A / D conversion unit 19, the storage unit 13, the MOSFET 16, the temperature detection unit 17, the button 11, the battery exhaustion alarm LED 18, and the wireless unit 14.

  In the above configuration, when the control unit 15 recognizes that the user has pressed the button 11, the control unit 15 notifies the receiver side (not shown) through the wireless unit 14. At that time, the control unit 15 operates the MOSFET 16 so that the voltage of the battery 12 is transmitted to the A / D conversion unit 19.

  The A / D converter 19 samples the voltage of the battery 12 and the ambient temperature information from the temperature detector 17 into digital quantities. The control unit 15 acquires the voltage of the battery 12 and ambient temperature information from the A / D conversion unit 19. Then, the battery low alarm threshold value corresponding to the ambient temperature information is read from the storage unit 13, and the voltage of the battery 12 is compared with the battery low alarm threshold value. When the voltage of the battery 12 is equal to or lower than the threshold value, a battery out alarm is notified to the receiver side.

  First, an example of the communication method of the present invention will be described with reference to FIG. FIG. 3 is a diagram showing an example of battery voltage versus time characteristics of the wireless notification device according to the present invention. According to the Radio Law, a time when radio waves can be emitted in one communication is determined. Therefore, in the present invention, in order to increase the accuracy of radio wave transmission / reception, the fact that the button 11 has been pressed is transmitted to the receiver side using a plurality of packets within the time limit of the radio wave law.

  On the other hand, the voltage of the battery 12 rapidly decreases from the standby voltage because the current consumption increases by starting communication. In addition, the capacity of the battery 12 decreases as the communication time increases and current is consumed, and the voltage also decreases. Therefore, in order to accurately detect a battery exhaustion alarm, the control unit 15 performs a battery voltage measurement at a heavy load during communication, and adds the battery exhaustion alarm detection result information to each packet generation. That is, the control unit 15 performs voltage measurement at a point marked with X in FIG. As a result, even in the case of a system that transmits a plurality of packets in a single transmission, it is possible to determine a battery exhaustion alarm with a low voltage value under heavy load.

  In addition, by detecting the voltage value of the battery when creating the packet information, it is not necessary to perform communication only to inform the receiver that the remaining battery level is low after detecting a decrease in the remaining battery level. Therefore, it is possible to obtain an effect of reduction of current consumption due to quick response and unnecessary communication reduction.

  In addition, since the battery remaining amount detection result measured independently is added to each of the plurality of packets, it is determined that the remaining battery amount is low only when the battery remaining low alarm is detected for two or more consecutive packets. This makes it possible to prevent erroneous detection due to the influence of noise or the like.

  Next, the reason why the present invention can prevent erroneous detection of battery exhaustion will be described. FIG. 4 is a voltage versus time characteristic diagram showing an example of the relationship between the detected battery voltage value and noise. The battery voltage value is measured and used to determine a battery exhaustion alarm, but the battery voltage tends to fluctuate particularly when the battery voltage is low (see the figure). In addition, the battery voltage is measured by analog value and digitized by the A / D converter, but there is a possibility that noise may be suddenly mixed due to the nature of the analog signal, and it may be erroneously determined that the battery is dead. is there.

  In addition, even when the battery voltage is sufficiently above the threshold, there is a possibility that it is erroneously determined that the voltage is low if noise is added to the measured data. In addition, since the voltage tends to fluctuate especially when the remaining battery level decreases, both the point A lower than the threshold voltage and the point B higher than the threshold voltage (see the same figure) may be measured. . Since the threshold value is set with a margin, in order to use up the battery capacity efficiently, there is a case where the voltage at point B does not have to be determined as a low voltage yet. Therefore, the battery voltage is measured when packet information is generated, and the battery voltage is measured independently for each packet.

  Next, an example of a method for determining a battery voltage threshold based on temperature will be described. FIG. 5 is a voltage versus battery capacity characteristic diagram showing an example of the relationship between battery voltage and battery capacity. Referring to the figure, an example of a curve at high temperature and a curve at low sound is displayed. Since the voltage at the time of high temperature drops more rapidly than that at the time of low sound, the threshold C at the time of high temperature is set to a point where the remaining battery capacity is higher than the threshold D at the time of low sound.

  Next, an example of the operation of the radio notification device according to the present invention will be described. FIG. 6 is a flowchart showing the operation of the first embodiment of the wireless notification device according to the present invention. The following operation relates to a battery capacity drop detection method. The following operation is executed by the control unit 15 by controlling the A / D conversion unit 19, the storage unit 13, the MOSFET 16, the temperature detection unit 17, the button 11, the battery exhaustion alarm LED 18, and the wireless unit 14.

  The user presses the button 11 when transmitting an emergency call (step S1). When recognizing that the button 11 has been pressed, the control unit 15 turns on the MOSFET 16 and controls the voltage of the battery 12 to be input to the A / D conversion unit 19 (step S2). Next, the A / D conversion unit 19 samples the voltage of the battery 12 and the ambient temperature detected by the temperature detection unit 17 into digital quantities (step S3).

  The control unit 15 acquires information on the voltage of the battery 12 and the ambient temperature from the A / D conversion unit 19. Then, the control unit 15 reads out the battery outage alarm threshold value corresponding to the acquired ambient temperature from the storage unit 13 (step S4), and compares the voltage of the battery 12 with the read out threshold value (step S5).

  If the voltage of the battery 12 is equal to or lower than the threshold (“YES” in step S5), the control unit 15 adds the battery exhaustion alarm information to the transmission packet (step S6). And the control part 15 transmits data to the receiver side (step S7).

  Next, the control unit 15 determines whether or not the transmitted packet is the final packet (step S8). If the transmitted packet is the final packet ("YES" in step S8), the MOSFET 16 is turned off (step S9). Then, the control unit 15 blinks or lights up the battery low alarm LED 18 in order to notify the user that the battery low alarm has been detected (step S10). On the other hand, if it is not the last packet in step S8 ("NO" in step S8), the process returns to step S3.

  When the voltage of the battery 12 exceeds the threshold value in step S5 (“NO” in step S5), the control unit 15 transmits data to the receiver side (step S11). In this case, the battery exhaustion alarm information is not added to the data.

  Next, the control unit 15 determines whether or not the transmitted packet is the final packet (step S12). If the transmitted packet is the final packet (“YES” in step S12), the MOSFET 16 is turned off (step S13). On the other hand, if it is not the last packet in step S12 (“NO” in step S12), the process returns to step S3.

  On the other hand, when a device on the receiver side (not shown) is notified that the portable radio notification device 2 has run out of battery (see step S7), it uses a PSTN (Public Switched Telephone Network) line or a cellular phone line and is not shown. Notify the center that the portable radio reporting device 2 is out of battery.

  As described above, according to the first embodiment of the present invention, the following effects can be obtained.

  The first effect is that the battery exhaustion alarm determination is performed at the time of a heavy load in which the voltage suddenly decreases, so that the determination can be performed with the lowest battery voltage.

  The second effect is that a battery exhaustion alarm determination is performed every time a packet is transmitted, so that the determination can be performed with a more accurate minimum voltage.

  The third effect is that, since the threshold value (determination value) is changed according to the ambient temperature, it is possible to prevent the battery from being determined to run out even though the battery capacity is present at low temperatures.

  The fourth effect is that since the threshold value (determination value) is changed according to the ambient temperature, an arbitrary battery capacity can be secured even at high temperatures.

  The fifth effect is that the MOSFET is turned off in a standby state in which no radio is used, so that current consumption can be saved and the battery life can be greatly extended.

  Next, a second embodiment will be described. The configuration of the second embodiment is the same as that of the first embodiment (see FIG. 2). In the first embodiment, battery exhaustion is detected when the battery voltage falls below the threshold even once. However, in the second embodiment, the battery runs out only when the battery voltage falls below the threshold twice in a row. Is detected.

  FIG. 7 is a flowchart showing the operation of the second embodiment of the radio notification device according to the present invention. The following operation is executed by the control unit 15 by controlling the A / D conversion unit 19, the storage unit 13, the MOSFET 16, the temperature detection unit 17, the button 11, the battery exhaustion alarm LED 18, and the wireless unit 14.

  The storage unit 13 stores information about the flag A and the flag B. The control unit 15 controls these flag information. As an example, when flag A is “1”, it indicates that the first battery voltage drop (below the threshold) has been detected, and when flag B is “1”, the second battery voltage drop (below the threshold) has been detected. It shows that. In the initial setting, the flag A and the flag B are set to “0”.

  The user presses the button 11 when transmitting an emergency call (step S21). When recognizing that the button 11 is pressed, the control unit 15 turns on the MOSFET 16 and controls the voltage of the battery 12 to be input to the A / D conversion unit 19 (step S22). Next, the A / D converter 19 samples the voltage of the battery 12 and the ambient temperature detected by the temperature detector 17 into a digital amount (step S23).

  The control unit 15 acquires information on the voltage of the battery 12 and the ambient temperature from the A / D conversion unit 19. And the control part 15 reads the threshold value of a battery exhaustion alarm corresponding to the acquired ambient temperature from the memory | storage part 13 (step S24).

  The control unit 15 reads information on the flag B from the storage unit 13 (step S25). Since the flag B is currently “0” (“NO” in step S25), the control unit 15 compares the voltage of the battery 12 with the read threshold value (step S26).

  If the voltage of battery 12 is equal to or lower than the threshold value (“YES” in step S26), since current flag A is “0” (“NO” in step S27), control unit 15 sets flag A to “0”. "1" is stored in the rewrite storage unit 13 (step S28).

  Since it is not yet the final packet (“NO” in step S29), the process returns to step S23. The controller 15 executes steps S24 and S25 again. Since the flag B is still “0” in step S25 (“NO” in step S25), the process proceeds to step S26.

  If the voltage of battery 12 is equal to or lower than the threshold value ("YES" in step S26), flag A is "1" ("YES" in step S27), so control unit 15 sets flag B to "0". Is stored in the rewrite storage unit 13 from "1" to "1" (step S30). And the control part 15 adds battery low alarm information to a transmission packet (step S31), and transmits data to a receiver (step S37).

  Since it is not yet the final packet (“NO” in step S29), the process returns to step S23. The control unit 15 executes steps S24 and S25 again. Since the flag B is “1” in step S25 (“YES” in step S25), the control unit 15 adds the battery exhaustion alarm information to the transmission packet (step S25). S31), data is transmitted to the receiver (step S37). If it is not the final packet (“NO” in step S29), the process returns to step S23 and the above operation is repeated.

  On the other hand, when the voltage of the battery 12 exceeds the threshold value in step S26 ("NO" in step S26), the control unit 15 rewrites the flag A to "0" and stores it in the storage unit 13 (step S32). The data is transmitted to the receiver (step S38). In this case, since the battery exhaustion is not detected, the battery exhaustion information is not added to the data to be transmitted.

  If the packet is the last packet in step S29 (“YES” in step S29), the control unit 15 turns off the MOSFET 16 (step S33). If the flag B is “1” (“YES” in step S34), the control unit 15 blinks or lights the battery low alarm LED 18 to notify the user that the battery low alarm has been detected. (Step S35).

  Then, the control unit 15 stores the flag “B” as “0” in the rewrite storage unit 13 (step S36). This is the end of the process. On the other hand, when the flag B is “0” in step S34 (“NO” in step S34), the process is ended.

  As described above, according to the second embodiment of the present invention, when the battery voltage determination information of the previous one time is retained, the battery runs out for the first time when the continuous battery voltage becomes the threshold value or less twice. It becomes possible to judge. As a result, it is possible to prevent the battery from being determined to run out due to the influence of noise or due to fluctuations in battery voltage.

  Next, a third embodiment will be described. In the portable wireless notification device according to the third embodiment, the battery exhaustion alarm is periodically determined. FIG. 8 is a configuration diagram of a third embodiment of the portable radio notification device according to the present invention. In addition, the same number is attached | subjected to the component similar to FIG. 2, and the description is abbreviate | omitted.

  Referring to FIG. 8, the configuration of the portable wireless notification device 3 in the third embodiment is different from the configuration of the portable wireless notification device 2 in the first embodiment of FIG. 2 in that a timer 21 is added. Only the points are the same, and other configurations are the same as those of the first embodiment.

  The timer 21 is configured to start each time the button 11 is pressed. When the timer 21 is activated, the timer 21 counts for a certain period of time. When the timer 21 counts up, the count value is reset, and counting is started again. Counting is repeated in this way.

  On the other hand, when the button 11 is pressed again, the timer 21 is reset almost simultaneously and starts counting for a certain time again. An example of this operation is shown in FIG. FIG. 9 is a schematic diagram showing an example of the operation of the third embodiment.

  When the button 11 is pressed, the control unit 15 executes the operation shown in the first embodiment (see FIG. 6). Therefore, when the button 11 is pressed, data to be transmitted when the button 11 is pressed and battery exhaustion alarm information to be added thereto are transmitted to the receiver side.

  On the other hand, after a predetermined time has elapsed since the button 11 was pressed (when the timer 21 is counting up), the data transmitted by the control unit 15 is only the battery exhaustion alarm information. This is because the button 11 is not pressed after a certain period of time.

  Therefore, on the receiver side that has received this data, if the data to be transmitted when pressed and the battery-out alarm information to be added thereto are received, the button on the transmitter side (portable wireless notification device 3) It can be determined that 11 is pressed. On the other hand, when only the battery alarm information is received on the receiver side, it can be determined that the button 11 is not pressed.

  As described above, according to the third embodiment of the present invention, the determination of the battery exhaustion alarm is periodically performed at regular intervals, so that a period of time is provided between the user's button press and the next button press. Even if there is a gap, it is possible to maintain a voltage that can be reported reliably.

  Next, a fourth embodiment will be described. The fourth embodiment relates to a program for a battery capacity drop detection method in a radio notification device. A program for the battery capacity decrease detection method shown in the flowcharts of FIGS. 6 and 7 is stored in a memory (not shown) of the control unit 15 (see FIGS. 2 and 8).

  The control unit 15 reads the program from the memory, and controls the A / D conversion unit 19, the storage unit 13, the MOSFET 16, the temperature detection unit 17, the button 11, the battery exhaustion alarm LED 18, and the wireless unit 14 according to the program. Since the control content has already been described, the description thereof is omitted here.

  As described above, according to the fourth embodiment of the present invention, it is possible to accurately measure the battery voltage at the time of packet transmission, and more accurate by detecting the battery voltage for each packet. A program for a battery capacity drop detection method in a wireless notification device capable of detecting the minimum voltage is obtained.

  As other configurations, the following configurations can be applied to the present invention. First, in the control unit 15 (see FIGS. 2 and 8), the temperature detection unit 17 can be omitted if the microcontroller used in the control unit 15 includes temperature detection. Moreover, the battery low alarm LED 18 may be provided with a buzzer or a speaker to notify by sound. As a result, the alarm can be recognized even by a blind person or a color-weak person.

  2 sets an upper limit and a lower limit for the acquired ambient temperature, and when the ambient temperature falls outside the upper and lower limits (that is, as an example, the ambient temperature of the portable radio notification devices 2 and 3 is It is also possible to adopt a configuration in which the control unit 15 (see FIGS. 2 and 8) adds the information to the packet information and transmits it to the receiver side when the temperature is severe for the user to live. As a result, it is possible to confirm the safety of the user.

(Supplementary note 1) The wireless notification device includes a switch connected between the battery and the control unit,
When the button is pressed, the control unit closes the switch to start the battery voltage detection, and when the packet transmission is finished, the control unit opens the switch to end the battery voltage detection. Battery capacity drop detection method.

(Supplementary note 2) including a battery exhaustion alarm unit for displaying a battery exhaustion alarm on the wireless notification device,
2. The battery capacity according to claim 1, wherein when the control unit detects that the voltage of the battery is equal to or less than the threshold value once or twice, the battery capacity alarm unit displays an alarm. Degradation detection method.

  (Additional remark 3) When the said control part detects that the voltage of the said battery is less than the said threshold value once or twice continuously, it adds that the data which notifies the battery transmission to the data which transmits the said packet The battery capacity drop detection method according to Supplementary Note 1 or 2, wherein the battery capacity drop is detected.

(Supplementary note 4) A timer for measuring a predetermined time is included in the wireless notification device,
The control unit causes the timer to measure a certain time when the button is pressed, performs the packet transmission and determines whether the battery has run out when the button is pressed, and runs out of the battery every time the certain time elapses. 4. The battery capacity drop detection method according to any one of appendices 1 to 3, wherein the determination is performed.

  (Supplementary Note 5) A packet transmitted when the button is pressed is data to be reported by the user and data related to determination of battery exhaustion, and packets transmitted at regular intervals thereafter are data related to determination of battery exhaustion. The battery capacity decrease detection method according to appendix 4, wherein

1, 2, 3 Wireless reporting device
11 button
12 batteries
13 Memory unit
14 Radio section
15 Control unit
16 MOSFET
17 Temperature detector
18 Low battery alarm LED
19 A / D converter
21 timer

Claims (10)

A button for packet transmission;
A battery for power supply;
A storage unit for storing a battery voltage threshold value for detecting battery exhaustion;
A wireless unit that transmits packets;
A control unit that transmits a packet via the wireless unit when the button is pressed, and compares the voltage of the battery with a threshold stored in the storage unit for each packet and determines whether the battery is dead. A wireless notification device. Including a temperature detector for detecting the ambient temperature of the battery;
The storage unit stores a threshold value corresponding to the ambient temperature,
The said control part acquires the threshold value corresponding to the ambient temperature detected by the said temperature detection part from the said memory | storage part, and compares with the acquired threshold value of the voltage of the said battery, and performs determination of battery exhaustion. Item 1. The wireless notification device according to item 1. A switch connected between the battery and the control unit;
When the button is pressed, the control unit closes the switch to start the battery voltage detection, and when transmission of the packet ends, opens the switch to end the battery voltage detection. The radio notification device according to claim 1 or 2. Includes a low battery alarm section that displays a low battery alarm,
4. The control unit displays an alarm on the battery exhaustion alarm unit when it detects that the voltage of the battery is equal to or less than the threshold value once or continuously twice. The radio notification device according to the above.   The control unit, when detecting that the voltage of the battery is equal to or less than the threshold value once or twice, adds data notifying the battery transmission to the data to be transmitted with the packet. Item 5. The wireless notification device according to any one of items 1 to 4. Including a timer to measure a certain time,
The control unit causes the timer to measure a certain time when the button is pressed, performs the packet transmission and determines whether the battery has run out when the button is pressed, and runs out of the battery every time the certain time elapses. 6. The radio notification device according to claim 1, wherein the determination is performed.   The packet transmitted when the button is pressed is data to be reported by the user and data relating to determination of battery exhaustion, and thereafter the packets transmitted at regular intervals are data relating to determination of battery exhaustion. The radio notification device according to claim 6. Battery capacity in a radio notification device including a button for packet transmission, a battery for power supply, a storage unit for storing a battery voltage threshold value for battery exhaustion detection, a radio unit for transmitting a packet, and a control unit A drop detection method,
The control unit transmits a packet via the radio unit when the button is pressed, and compares the battery voltage with a threshold stored in the storage unit for each packet to determine whether the battery is dead. A battery capacity drop detection method. The wireless notification device includes a temperature detection unit that detects the ambient temperature of the battery, and the storage unit stores a threshold corresponding to the ambient temperature,
The said control part acquires the threshold value corresponding to the ambient temperature detected by the said temperature detection part from the said memory | storage part, and compares with the acquired threshold value of the voltage of the said battery, and performs determination of battery exhaustion. Item 9. The battery capacity decrease detection method according to Item 8. Battery capacity in a radio notification device including a button for packet transmission, a battery for power supply, a storage unit for storing a battery voltage threshold value for battery exhaustion detection, a radio unit for transmitting a packet, and a control unit A program for detecting a drop,
To cause the control unit to transmit a packet via the radio unit when the button is pressed, and to compare the battery voltage with a threshold value stored in the storage unit for each packet and execute a determination of battery exhaustion Program.

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