A battery load capacity detection circuit, a gas meter controller, and a gas meter

Abstract

This utility model belongs to the field of power supply detection technology for gas meter controllers, specifically disclosing a battery load capacity detection circuit. It includes a control unit, a simulated load detection unit, and an alarm indication unit. The control unit outputs a control signal to the simulated load detection unit, which generates a simulated load upon receiving the control signal. The control unit's acquisition terminal can collect the voltage of the tested battery before and after the load. The control unit is connected to the alarm indication unit to control the alarm indication unit to issue an alarm indication. When the load voltage of the tested battery is lower than a preset voltage threshold or the voltage drop before and after the load exceeds a preset threshold, the alarm indication unit issues an alarm. The battery load capacity detection circuit provided by this utility model has a fast response speed, can quickly detect whether the battery meets the usage requirements, significantly improves the reliability of gas meter use, and has a simple structure, strong practicality, can be integrated into existing products, and is easy to promote and apply.

Description

Technical Field

[0001] This utility model belongs to the field of power supply detection technology for gas meter controllers, specifically relating to a battery load capacity detection circuit, a gas meter controller, and a gas meter. Background Technology

[0002] With the increasing prevalence of smart remote gas meters, their power supply is mostly provided by dry cell batteries that users replace themselves. The performance of these batteries plays a decisive role in the stability of the device and the user experience. However, in practical applications, users often use batteries of varying quality, with some using inferior, falsely labeled, or aged batteries. While these batteries may provide normal voltage under no-load conditions, they are prone to sudden voltage drops under system workload, leading to problems such as abnormal data, a black LCD screen, a malfunctioning buzzer, or metering errors. This seriously affects the normal operation of the smart gas meter controller and the user experience, and may even pose safety hazards.

[0003] Traditional controllers only detect battery voltage and cannot determine whether the battery has sufficient load capacity. In particular, they cannot effectively identify and warn when the battery voltage is normal under no-load conditions but drops sharply once a load is applied. Utility Model Content

[0004] To overcome the shortcomings of the prior art, this utility model provides a low-cost, high-reliability battery load detection circuit and a gas meter controller and gas meter having the circuit.

[0005] This utility model is achieved through the following technical solution.

[0006] This invention provides a battery load capacity detection circuit, which is applied in a gas meter controller. It includes a control unit, a simulated load detection unit, and an alarm indication unit. The power supply terminal of the control unit can be electrically connected to the battery under test. The detection terminal of the simulated load detection unit can be electrically connected to the battery under test. The first output terminal of the control unit is electrically connected to the input terminal of the simulated load detection unit, and the acquisition terminal of the control unit is electrically connected to the output terminal of the simulated load detection unit. The control unit outputs a control signal to the simulated load detection unit through its first output terminal after the battery under test is connected. The simulated load detection unit forms a simulated load upon receiving the control signal. The acquisition terminal of the control unit can acquire the voltage of the battery under test before and after the load. The second output terminal of the control unit is electrically connected to the alarm indication unit to control the alarm indication unit to issue an alarm indication. The alarm indication unit is configured to issue an alarm indication when the load voltage of the battery under test is lower than a preset voltage threshold or when the voltage drop before and after the load exceeds a preset threshold.

[0007] As a further improvement to the above scheme, the simulated load detection unit includes a current-limiting resistor R1, transistors Q1 and Q2, a load resistor R2, voltage-dividing resistors R3 and R4, and a Schottky diode D1. One end of the current-limiting resistor R1 serves as the input terminal of the simulated load detection unit and is electrically connected to the input terminal of the control unit. The other end of the current-limiting resistor R1 is electrically connected to the base of transistor Q1 and the collector of transistor Q2, respectively. The collector of transistor Q1 is electrically connected to the cathode of Schottky diode D1. The emitter of transistor Q1 and the base of transistor Q2 are electrically connected to one end of the load resistor R2. The emitter of transistor Q2 and the other end of load resistor R2 are grounded. The anode of Schottky diode D1 and one end of voltage divider resistor R3 are electrically connected. The anode of Schottky diode D1 or the end of voltage divider resistor R3 connected to Schottky diode D1 serves as the detection terminal of the analog load detection unit and is electrically connected to the battery under test. The other end of voltage divider resistor R3 is electrically connected to voltage divider resistor R4. The other end of voltage divider resistor R4 is grounded. The end of voltage divider resistor R3 connected to voltage divider resistor R4 or the end of voltage divider resistor R4 connected to voltage divider resistor R3 serves as the output terminal of the analog load detection unit and is electrically connected to the acquisition terminal of the control unit.

[0008] As a further improvement to the above solution, the control unit is an MCU.

[0009] As a further improvement to the above solution, the alarm indication unit is at least one of an LCD display, a buzzer, and an indicator light.

[0010] As a further improvement to the above scheme, the current limiting resistor R1 has a resistance of 1KΩ, the load resistor R2 has a resistance range of 1Ω to 10Ω, and the voltage divider resistors R3 and R4 have a resistance of 100KΩ.

[0011] This invention provides a gas meter controller having a battery load capacity detection circuit as described above.

[0012] This utility model provides a gas meter having a gas meter controller as described above.

[0013] The beneficial effects of this utility model are:

[0014] Compared with the prior art, the battery load capacity detection circuit in this utility model can monitor the voltage change of the battery in real time when a certain load is applied. When the voltage drop exceeds the set threshold or the load voltage is lower than the start-up voltage threshold, the alarm indicator unit can issue an alarm prompt in time, promptly warn of inferior batteries, determine whether the power supply capacity of the gas meter battery meets the standard, and remind the user to replace it with a high-quality battery, thereby effectively avoiding equipment abnormalities caused by insufficient battery performance.

[0015] The battery load capacity detection circuit provided by this utility model has a fast response speed and can quickly detect whether the battery meets the usage requirements, significantly improving the reliability of the gas meter. At the same time, it has a simple structure, low cost, and strong practicality, and can be integrated into existing products, making it easy to promote and apply. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the functional modules of this utility model;

[0017] Figure 2 This is a circuit diagram of the analog load detection unit in this utility model;

[0018] In the diagram: 1. Control unit; 2. Simulated load detection unit; 3. Alarm indicator unit; 4. Battery under test. Detailed Implementation

[0019] To further illustrate the technical solution of this utility model, the following description is provided in conjunction with the accompanying drawings and embodiments.

[0020] like Figures 1 to 2 As shown, this utility model discloses a battery load capacity detection circuit, which is applied in a gas meter controller and includes a control unit 1, a simulated load detection unit 2, and an alarm indication unit 3.

[0021] Furthermore, the detection end of the simulated load detection unit 2 can be electrically connected to the battery under test 4, the first output end of the control unit 1 is electrically connected to the input end of the simulated load detection unit 2, and the acquisition end of the control unit 1 is electrically connected to the output end of the simulated load detection unit 2. The control unit 1 is used to output a control signal to the simulated load detection unit 2 through the first output end after connecting the battery under test 4. The simulated load detection unit 2 is used to form a simulated load after receiving the control signal. The acquisition end of the control unit 1 can acquire the voltage of the battery under test 4 before and after the load. The second output end of the control unit 1 is electrically connected to the alarm indication unit 3 to control the alarm indication unit 3 to perform an alarm indication. The alarm indication unit 3 is configured to perform an alarm indication when the load voltage of the battery under test 4 is lower than a preset voltage threshold or the voltage drop before and after the load exceeds a preset threshold.

[0022] In some embodiments, the analog load detection unit 2 includes a current-limiting resistor R1, transistors Q1 and Q2, a load resistor R2, voltage-dividing resistors R3 and R4, and a Schottky diode D1. One end of the current-limiting resistor R1 serves as the input terminal of the analog load detection unit 2 and is electrically connected to the input terminal of the control unit 1. The other end of the current-limiting resistor R1 is electrically connected to the base of transistor Q1 and the collector of transistor Q2, respectively. The collector of transistor Q1 is electrically connected to the cathode of Schottky diode D1, and the emitter of transistor Q1 and the base of transistor Q2 are electrically connected to the load resistor R1. One end of 2 is electrically connected, the emitter of transistor Q2 and the other end of load resistor R2 are grounded, the anode of Schottky diode D1 and one end of voltage divider resistor R3 are electrically connected, the anode of Schottky diode D1 or the end of voltage divider resistor R3 connected to Schottky diode D1 is used as the detection terminal of analog load detection unit 2 and is electrically connected to the positive terminal of the battery under test 4, the other end of voltage divider resistor R3 is electrically connected to voltage divider resistor R4, the other end of voltage divider resistor R4 is grounded, the end of voltage divider resistor R3 connected to voltage divider resistor R4 or the end of voltage divider resistor R4 connected to voltage divider resistor R3 is used as the output terminal of analog load detection unit 2 and is electrically connected to the acquisition terminal of control unit 1.

[0023] In some embodiments, the control unit 1 is an MCU, the MCU model is FM33LG048, the transistor Q1 model is D882, the transistor Q2 model is S8050, and the Schottky diode D1 model is SS34.

[0024] Furthermore, transistor Q1 serves as the main current path transistor, and transistors Q2 and Q1 together form a negative feedback amplification structure. Load resistor R2 is used to simulate the load and form negative feedback. Schottky diode D1 is used to prevent reverse battery flow. Voltage divider resistors R3 and R4 work together with the MCU's acquisition terminal to collect the voltage drop of the tested battery in real time.

[0025] In some embodiments, the alarm indication unit 3 is at least one of an LCD display, a buzzer, and an indicator light.

[0026] In some embodiments, when the alarm indicator unit 3 has an LCD display, the display shows "Please replace the battery"; when the alarm indicator unit 3 has a buzzer, the buzzer sounds intermittently; when the alarm indicator unit 3 has an indicator light, the indicator light flashes.

[0027] In some embodiments, the current-limiting resistor R1 has a resistance of 1KΩ, the load resistor R2 has a resistance range of 1Ω to 10Ω, and the voltage divider resistors R3 and R4 have a resistance of 100KΩ.

[0028] This invention provides a gas meter controller having a battery load capacity detection circuit as described above.

[0029] This utility model provides a gas meter having a gas meter controller as described above.

[0030] The working principle of the gas meter controller battery load capacity detection circuit is as follows:

[0031] After the user replaces the battery, the MCU outputs a high-level control signal (approximately 3.3V), and transistor Q1 begins to conduct. As transistor Q1 conducts, the current gradually increases, resulting in a voltage drop across the load resistor R2 (approximately 3.3Ω). The voltage at the end of the load resistor R2 connected to the emitter of transistor Q1 rises. Since the base of transistor Q2 is connected to the emitter of transistor Q1, the emitter voltage of transistor Q2 also rises. Meanwhile, the base of transistor Q1 remains connected to the control signal through the current-limiting resistor R1. Therefore, the voltage across transistor Q1... BE When the voltage across the load resistor R2 is high enough (e.g., reaching 0.7V), transistor Q2 will enter the cutoff or linear region, no longer conducting or with reduced conduction capability. This causes the base voltage of transistor Q1 to rise, its conduction capability to weaken, and the current to decrease. Consequently, the voltage drop across the load resistor R2 decreases, forming a negative feedback regulation mechanism.

[0032] After transistor Q1 is turned on, current flows through the load resistor R2, forming a voltage drop. If transistor Q2 remains on, the voltage across the load resistor R2 is: V R2 =V BE(Q2) ≈0.7V, then the current on the load resistor R2 is approximately 0.212 A. The circuit eventually stabilizes at an output current of approximately 210mA, forming a current-limited constant current load. At the same time, the voltage change of the battery under this load current is monitored by the MCU's acquisition terminal through voltage divider R3 and voltage divider R4.

[0033] If the voltage drop before and after the load exceeds a preset threshold or the load voltage is lower than the minimum starting voltage, it is determined that the battery is of poor quality, and the alarm indicator unit will send a battery replacement reminder to the user.

[0034] The working process of the gas meter controller battery load capacity detection circuit is as follows:

[0035] When the MCU detects that the user has installed a battery, the MCU outputs a control signal to control the load resistor R2 to be connected to the circuit for a short time (e.g., 0.5 seconds).

[0036] The MCU samples the voltage before and after the battery load and calculates the voltage difference before and after the load.

[0037] If the voltage drop before and after the load exceeds a preset threshold (e.g., 0.3V) or the load voltage is lower than the minimum starting voltage (e.g., 4.5V), the battery load capacity is deemed insufficient.

[0038] The MCU controls the LCD display to show "Please replace battery" and / or the indicator light to flash and / or the buzzer to sound intermittently.

[0039] If the battery meets the requirements, the gas meter controller will enter the normal operating mode.

[0040] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model.

[0041] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A battery load capacity detection circuit, applied in a gas meter, characterized in that: The device includes a control unit (1), a simulated load detection unit (2), and an alarm indication unit (3). The detection end of the simulated load detection unit (2) can be electrically connected to the battery under test (4). The first output end of the control unit (1) is electrically connected to the input end of the simulated load detection unit (2). The acquisition end of the control unit (1) is electrically connected to the output end of the simulated load detection unit (2). The control unit (1) is used to output a control signal to the simulated load detection unit (2) through the first output end after connecting the battery under test (4). The simulated load detection unit (2) is used to form a simulated load after receiving the control signal. The acquisition end of the control unit (1) can acquire the voltage of the battery under test (4) before and after the load. The second output end of the control unit (1) is electrically connected to the alarm indication unit (3) to control the alarm indication unit (3) to perform an alarm indication. The alarm indication unit (3) is configured to perform an alarm indication when the load voltage of the battery under test (4) is lower than a preset voltage threshold or the voltage drop before and after the load exceeds a preset threshold.

2. The battery load capability detection circuit of claim 1, wherein: The simulated load detection unit (2) includes a current-limiting resistor R1, transistors Q1 and Q2, a load resistor R2, voltage divider resistors R3 and R4, and a Schottky diode D1. One end of the current-limiting resistor R1 serves as the input terminal of the simulated load detection unit (2) and is electrically connected to the input terminal of the control unit (1). The other end of the current-limiting resistor R1 is electrically connected to the base of transistor Q1 and the collector of transistor Q2, respectively. The collector of transistor Q1 is electrically connected to the cathode of Schottky diode D1. The emitter of transistor Q1 and the base of transistor Q2 are electrically connected to one end of the load resistor R2. The emitter of transistor Q2... The other end of the load resistor R2 is grounded. The anode of the Schottky diode D1 is electrically connected to one end of the voltage divider resistor R3. The anode of the Schottky diode D1 or the end of the voltage divider resistor R3 connected to the Schottky diode D1 is used as the detection terminal of the analog load detection unit (2) and electrically connected to the positive electrode of the battery under test (4). The other end of the voltage divider resistor R3 is electrically connected to the voltage divider resistor R4. The other end of the voltage divider resistor R4 is grounded. The end of the voltage divider resistor R3 connected to the voltage divider resistor R4 or the end of the voltage divider resistor R4 connected to the voltage divider resistor R3 is used as the output terminal of the analog load detection unit (2) and electrically connected to the acquisition terminal of the control unit (1).

3. The battery load capability detection circuit of claim 1, wherein: The control unit (1) is an MCU.

4. The battery load capability detection circuit of claim 1, wherein: The alarm indicator unit (3) is at least one of an LCD display, a buzzer, and an indicator light.

5. The battery load capability detection circuit of claim 2, wherein: The current-limiting resistor R1 has a resistance of 1KΩ, the load resistor R2 has a resistance range of 1Ω to 10Ω, and the voltage divider resistors R3 and R4 have a resistance of 100KΩ.

6. A gas meter controller characterized by: Includes a battery load capacity detection circuit as described in any one of claims 1 to 5.

7. A gas meter characterised in that: Including the gas meter controller as described in claim 6.

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