Mechanical counter of remote transmission electricity meter

Abstract

The invention relates to the technical field of counters, in particular to a mechanical counter of a remote transmission ammeter, which comprises a counter shell and a character wheel group rotatably assembled in the counter shell, the character wheel group is composed of a plurality of coaxially arranged character wheels, ten groups of white scale marks are uniformly preset on the circumferential surface of each character wheel along the circumferential direction in a surrounding manner, and the number of the white scale marks is 10. White scale marks are arranged on the counter shell, infrared reflection coatings are adopted for the white scale marks, infrared absorption coatings are adopted for the rest areas of the unit-bit character wheels and the whole areas of the rest character wheels, an infrared sensing module is fixedly assembled in the counter shell corresponding to the installation positions of the unit-bit character wheels, and a verification remote transmission unit is fixed on the inner side of the counter shell. The infrared sensing module is composed of an active infrared sensor, an infrared driving module, a signal amplification module and a shaping module. The invention aims to solve the problems that a traditional mechanical counter needs manual regular meter reading, a large amount of manpower cost is consumed, meter reading errors exist, and meter reading is missed.

Description

Technical Field

[0001] This invention relates to the field of counter technology, specifically to a mechanical counter for a remote-reading electricity meter. Background Technology

[0002] The core component of traditional mechanical electricity meters is the mechanical counter, which uses gear sets and carry mechanisms to drive the digit wheel to count. Its stable structure and low cost have led to its widespread use in the electricity meter industry. However, with the advancement of intelligent and digital transformation of power systems, the inherent defects of traditional mechanical counters have become increasingly apparent. Adopting a purely mechanical design, it lacks data digitization and transmission capabilities, making it unable to interface with remote monitoring platforms of the power system. It can only record local electricity data in isolation, forming typical data silos. This limitation directly leads to electricity metering relying on regular manual meter readings. This not only requires a large investment of manpower to build a meter reading team and bear the manpower and time costs of periodic round trips, but also suffers from the vulnerability of manual readings to factors such as light and environmental obstructions, and the difficulty in avoiding human error. Furthermore, users being away or the meter being installed in a concealed location can cause missed or incorrect readings, affecting the accuracy and timeliness of electricity billing. It is no longer suitable for the high-efficiency and precise requirements of modern power management. Summary of the Invention

[0003] The purpose of this invention is to provide a mechanical counter for a remote electricity meter to solve the problems of traditional mechanical counters that require manual meter reading periodically, which consumes a lot of manpower and also suffers from meter reading errors and missed readings.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A mechanical counter for a remote-reading electricity meter includes a counter housing and a digit wheel assembly rotatably mounted inside the counter housing. The digit wheel assembly consists of multiple coaxially arranged digit wheels. Ten preset white scale lines are evenly arranged around the circumference of the digit wheel in the unit position. The white scale lines are coated with an infrared reflective coating. The remaining areas of the digit wheel in the unit position and the entire area of ​​the remaining digit wheels are coated with an infrared absorbent coating. An infrared sensing module is fixedly mounted inside the counter housing at the installation position corresponding to the unit digit wheel. A verification remote-reading unit is fixedly mounted inside the counter housing.

[0005] Preferably, the infrared sensing module comprises an active infrared sensor, an infrared driving module, a signal amplification module, and a shaping module. The infrared driving module is electrically connected to the transmitting end of the active infrared sensor, the signal output end of the receiving end of the active infrared sensor is connected to the signal amplification module, and the signal amplification module is electrically connected to the shaping module.

[0006] Preferably, the axes of the active infrared sensor's transmitter and receiver intersect at the white scale line's rotation trajectory.

[0007] Preferably, the verification remote transmission unit integrates an MCU main control module, a camera, an OCR recognition module, and an NBIoT wireless communication module. The MCU main control module is communicatively connected to the shaping module, and is also communicatively connected to both the OCR recognition module and the NBIoT wireless communication module. The camera is communicatively connected to the MCU main control module.

[0008] Preferably, the camera is fixedly mounted on the housing of the verification remote transmission unit, and the camera lens faces the digital display surface of the digit wheel, with the shooting range covering the digital display area of ​​all digit wheels.

[0009] Preferably, the receiving end of the active infrared sensor outputs a transition signal, which is amplified by a signal amplification module and then converted into a standard TTL pulse signal by a shaping module. The MCU main control module captures the TTL pulse signal and calculates the electronic count value based on the formula: pulse number × 0.1kWh = electronic count value.

[0010] Preferably, the camera captures the image of the character wheel assembly and transmits it to the OCR recognition module. The OCR recognition module extracts the displayed numbers of each character wheel and splices them together according to the arrangement of the character wheels to obtain the mechanical reading. The OCR recognition module transmits the mechanical reading to the MCU main control module. The MCU main control module performs a difference calculation between the mechanical reading and the electronic counting value. When the absolute value of the deviation exceeds 1kWh, an abnormal alarm mechanism is triggered.

[0011] Preferably, the counter housing surface has an observation window corresponding to the digital display area of ​​the character wheel group. The observation window is made of transparent PC material and the viewing area completely covers the digital display surface of all character wheels.

[0012] Compared with the prior art, the beneficial effects of the present invention are: 1. It can transmit data remotely in real time, collect electronic count values ​​every hour and upload them to the cloud management platform, completely breaking the data silo dilemma of traditional mechanical meters. It eliminates the need for manual on-site meter reading, which not only greatly reduces manpower and time costs, but also avoids problems such as missed readings, incorrect readings, and estimated readings that may occur during manual meter reading. It can achieve significant savings in annual operating costs related to manual meter reading and improve the intelligence and efficiency of metering management. 2. An innovative mechanical and electronic dual redundancy verification scheme is adopted. OCR image recognition technology is triggered daily to read the mechanical digit wheel readings and compare them with the data of the electronic counting module in real time. This mechanism can accurately identify various abnormal scenarios such as digit wheel tampering and counting deviation, realize timely detection and early warning of abnormal situations, ensure the authenticity and integrity of measurement data, and avoid measurement inaccuracies caused by the failure of a single module. 3. Using infrared light recognition technology, non-contact data acquisition is achieved by accurately capturing the white scale line. There is no physical contact intervention throughout the process, which avoids the long-term wear and tear, component jamming and other losses caused by traditional contact acquisition and mechanical structure friction. At the same time, it does not affect the original operating logic of the original mechanical counting module, ensuring that the long-term stability and measurement accuracy of mechanical counting are not disturbed, and extending the overall service life of the equipment. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is the electrical connection diagram for infrared light data acquisition in this invention; Figure 3 This is an electrical connection diagram for camera data acquisition in this invention.

[0014] In the picture: 1. Counter housing; 2. Dial wheel; 3. White scale lines; 4. Active infrared sensor; 5. Camera. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please see Figure 1 and Figure 3 The present invention provides a technical solution.

[0017] A mechanical counter for a remote-reading electricity meter includes a counter housing 1 and a digit wheel assembly rotatably mounted inside the counter housing 1. The digit wheel assembly consists of multiple digit wheels 2 arranged coaxially in sequence. Each digit wheel 2 achieves stable rotation and precise positioning through a pre-set transmission shaft inside the counter housing 1, ensuring the smoothness of the counting process. Adjacent digit wheels 2 are linked through a built-in carry mechanism (such as a gear and pawl meshing structure), which can realize step-by-step carry from low to high positions, thereby forming a standard decimal counting logic. It should be noted that the rotation connection method of the digit wheels 2, the transmission shaft positioning structure, and the carry linkage logic are all inherent core mechanical structures of the mechanical counter. The technical improvement of this invention does not involve this original structure, and does not involve any form of disassembly, modification, or replacement.

[0018] The units digit wheel 2, located on the far right of the digit wheel group, has ten pre-set white scale lines 3 evenly surrounding its circumference. Each set of white scale lines 3 corresponds to one-tenth of a revolution of the units digit wheel 2, precisely matching the signal sampling frequency of the infrared sensor module. This provides a clear positioning reference for infrared signal recognition. The white scale lines 3 are coated with an infrared reflective coating (such as white high-gloss paint), which maximizes the reflection efficiency of infrared signals. The remaining areas of the units digit wheel 2, except for the white scale lines 3, as well as the entire area of ​​all other digit wheels 2 in the digit wheel group except for the units digit, are uniformly coated with an infrared absorbing coating (such as black matte paint). This effectively absorbs incident infrared light and avoids stray light reflection. Through this differentiated design of coating material and coverage area, the effective range of infrared reflected signals can be strictly limited, ensuring that the infrared sensor module can only capture the target signal fed back by the white scale lines 3 of the units digit wheel 2, thus guaranteeing the accuracy and stability of the counting signal acquisition.

[0019] Inside the counter housing 1, corresponding to the mounting position of the units digit wheel 2, an infrared sensing module is fixedly installed. The infrared sensing module consists of an active infrared sensor 4, an infrared drive module, a signal amplification module, and a shaping module. Each module is integrated and interconnected through a PCB board inside the infrared sensing module housing. The emitting end of the active infrared sensor 4 uses an infrared emitting diode in the 850nm near-infrared band. This wavelength has the advantages of both penetration and resistance to ambient light interference. Its operating current is set to an adjustable range of 5~20mA to adapt to the signal strength requirements under different installation gaps. The receiving end is matched with a phototransistor with a response wavelength range of 700~1100nm, which is precisely matched with the wavelength of the emitting end.

[0020] The infrared driving module is connected to the transmitter via wiring on the PCB board inside the infrared sensing module housing, providing a continuous and constant operating current to the infrared emitting diode. The signal output of the receiver is connected to the signal amplification module via wiring on the PCB board. The signal amplification module amplifies the weak photoelectric conversion signal output by the receiver, and the amplification factor can be adjusted as needed in the range of 100 to 500 times. It can amplify weak level transition signals to a recognizable range. The amplified signal is then transmitted to the signal shaping module via wires.

[0021] The signal shaping module has a built-in Schmitt trigger. The shaping module converts the amplified signal into a standard TTL level pulse through the Schmitt trigger, and finally connects to the control circuit with the MCU main control module as the core in the verification remote transmission unit through wires, so as to provide a reliable digital signal input for the counting logic operation of the MCU main control module.

[0022] The axes of the transmitter and receiver of the active infrared sensor 4 intersect on the rotation trajectory of the white scale line 3 on the surface of the unit digit wheel 2, ensuring that when each set of white scale lines 3 passes through this position, it can trigger effective signal interaction between the transmitter and receiver, realizing the detection of scale lines without omission.

[0023] To achieve automated verification and remote transmission of mechanical counter readings, a verification and transmission unit is bolted to the inside of the counter housing 1. This unit integrates an MCU main control module, a camera 5, an OCR recognition module, an NBIoT wireless communication module, and a lithium-ion battery. All modules are fixedly mounted on a PCB board inside the verification and transmission unit housing using standardized soldering processes. Signal interaction between modules is achieved through circuitry on the board. The camera 5 is fixedly mounted at a pre-set window in the verification and transmission unit housing, with its lens facing the digital display surface of the digit wheel 2, covering the entire digital display area of ​​the digit wheel 2. The MCU main control module, as the core control unit, coordinates the entire process, including camera 5 triggering, OCR recognition calculation, and NBIoT data transmission. Operators can directly read the displayed numbers on the surface of the digit wheel 2 through the transparent viewing window reserved in the counter housing 1, or they can periodically or as needed capture images of the digit wheel group's numbers using the camera 5 in the verification and transmission unit. After the OCR recognition module quickly completes the digital recognition and data parsing, the standardized reading data is remotely transmitted to the backend management system via the NBIoT module, enabling remote acquisition and real-time monitoring of the readings. These two methods complement each other, balancing on-site verification and remote management needs.

[0024] The MCU main control module uses a low-power microcontroller (such as STM32L051). The GPIO interface of the MCU main control module is connected to the signal output terminal of the shaping module through wires to receive the shaped standard TTL level pulse signal. This signal serves as the core trigger source for the rotation counting of the word wheel 2, providing the MCU with accurate counting logic. The UART interface of the MCU main control module is connected to the UART pins of the OCR recognition module and the UART pins of the NBIoT wireless communication module through PCB wiring. The SPI communication pin of the camera 5 is connected to the SPI interface socket on the PCB board through a ribbon cable. This socket is connected to the SPI interface of the MCU main control module through PCB wiring to form a complete SPI signal transmission path, ensuring the physical fixity of signal transmission.

[0025] Camera 5 uses a 1-megapixel high-definition CMOS image sensor with a resolution of 1280×720 pixels. This resolution can clearly capture the digital details on the surface of the character wheel 2, meeting the image quality requirements of OCR recognition. The frame rate is optimized to 1fps, maximizing power consumption reduction while ensuring image clarity. The output image format is grayscale, which can be directly adapted to the preprocessing process of the subsequent OCR recognition module.

[0026] The OCR recognition module uses a character recognition chip, such as the MX1200, to perform noise reduction, binarization, and character segmentation preprocessing on the captured grayscale image before recognizing the digits 0-9 on character wheel 2. After recognition, the standardized digital results are transmitted to the MCU main control module in real time through the UART interface to provide data support for reading verification.

[0027] The NBIoT wireless communication module uses an industrial-grade communication module, such as the Huawei BC25, which is specifically responsible for remotely transmitting data such as the readings of the word wheel 2 integrated by the MCU and the verification results of the counting pulses to the background management system, so as to realize real-time monitoring and remote traceability of the data.

[0028] The lithium-ion battery used is model ER34615, which is fixed inside the remote transmission unit housing via the battery compartment.

[0029] During the actual operation of the electricity meter, its internal mechanical transmission mechanism drives the digit wheel group to rotate synchronously through a preset transmission ratio. The rotation of the units digit wheel 2 directly reflects the real-time power consumption. When the units digit wheel 2 rotates during the power metering process, the ten sets of white scale lines 3 on its circumference surface will sequentially pass through the intersection point of the infrared light path of the active infrared sensor 4. At this time, the infrared light continuously emitted by the transmitter is reflected by the reflective coating of the white scale lines 3 and captured by the receiver, triggering the receiver to output a high-level signal. When the black infrared absorption coating area of ​​the digit wheel 2 passes through this path, the infrared light is high-level... Due to the lack of reflected light input, the receiving end outputs a low-level signal. This alternating high and low level signal generated by the rotation of the digit wheel 2 is first amplified by 100 to 500 times by the signal amplification module, and then converted into a standard TTL pulse signal by the Schmitt trigger of the shaping module. Since a set of white scale lines 3 completes one cycle of infrared light reflection and blocking for every tenth of a revolution of the unit digit wheel 2 (corresponding to 0.1 kWh of power consumption), a complete pulse signal is output for every tenth of a revolution. The pulse frequency has a strict linear relationship with the rotation speed of the digit wheel 2.

[0030] The MCU main control module captures the pulse signal in real time through the GPIO interface and accumulates the number of pulses. At the same time, it dynamically updates the internal electronic count value according to the preset metering logic using the formula "number of pulses × 0.1kWh = electronic count value". For example, when ten pulses are accumulated, the electronic count value is updated to 1.0kWh, which perfectly matches the mechanical reading displayed when the units digit wheel 2 rotates one revolution. This process ensures that the electronic count value and the mechanical reading of the units digit wheel 2 remain synchronized through the linkage of real-time signal acquisition at the hardware level and real-time calculation at the software level, providing accurate reference data for subsequent reading verification.

[0031] In terms of verification logic, the MCU main control module adopts a timed triggering mechanism. It automatically starts a full-process verification once a day at a preset time (such as 3:00 a.m., to avoid peak electricity consumption periods and reduce interference from frequent rotation of the digit wheel 2). Before the verification starts, the MCU first determines whether the unit digit wheel 2 is in a stable state by continuously monitoring the pulse signal output by the infrared sensor module. Specifically, it samples the shaped TTL pulse in real time through the GPIO interface. If no level change is detected for more than 1 second, that is, the digit wheel 2 does not rotate, it is determined that the digit wheel group is in a stationary state, ensuring that the digits of the digit wheel 2 are clearly displayed when shooting.

[0032] After confirming that the character wheel 2 is stable, the MCU sends a shooting command to the camera 5 through the SPI interface to control the camera 5 to capture the complete display screen of the character wheel group. After the shooting is completed, the image data is transmitted to the OCR recognition module in real time via the SPI bus. The module optimizes the image according to the preprocessing process, and then accurately extracts the display digits of each character wheel 2 through the digital recognition model, and splices them into a complete mechanical reading according to the arrangement order of the character wheels 2. The recognition result is fed back to the MCU through the UART interface.

[0033] After receiving the mechanical reading, the MCU first converts it into a numerical format consistent with the electronic count value, and then performs a difference calculation with its own accumulated electronic count value, such as 15.0 kWh. When the absolute value of the difference between the two is ≤1 kWh (e.g., the electronic count value of 12.3 kWh and the mechanical reading of 12.0 kWh have a difference of 0.3 kWh), the counting system is considered to be operating normally. When the absolute value of the difference exceeds 1 kWh (e.g., the electronic count value of 15.0 kWh and the mechanical reading of 13.5 kWh have a difference of 1.5 kWh), an abnormal alarm mechanism is immediately triggered, and the MCU controls the NBIoT module to send alarm information to the background management system through the UART interface.

[0034] To accommodate the needs of manual reading on site, an observation window is provided on the surface of the counter housing 1 corresponding to the digital display area of ​​the character wheel group. The observation window is made of highly transparent PC material, and the viewing area completely covers the digital display surface of all the character wheels 2, while maintaining a reasonable viewing distance from the surface of the character wheels 2. Operators can read the mechanical reading of each character wheel 2 intuitively and clearly through the observation window without disassembling the housing, which is convenient for on-site inspection and verification.

[0035] The process of using this solution is as follows: When the meter is running, the internal mechanical transmission mechanism drives the digit wheel group to rotate synchronously according to the preset transmission ratio. Every tenth of a revolution of the units digit wheel 2 corresponds to 0.1kWh of power consumption. The white scale line 3 on its circumference surface will pass through the intersection of the axes of the transmitter and receiver of the infrared sensor module, reflect infrared light and trigger the receiver to output a high level. When the black absorption coating area passes through, the receiver outputs a low level. The alternating high and low level signals are amplified and shaped by the amplification module and the shaping module to form a standard TTL pulse signal, which is transmitted to the MCU main control module in real time.

[0036] The MCU main control module captures TTL pulse signals through the GPIO interface and dynamically updates the data according to the logic of pulse number × 0.1kWh = electronic count value. The MCU main control module starts automatic verification at a preset time every day to ensure data accuracy. Before verification, the MCU monitors the pulse signal to determine whether the character wheel 2 is stationary to avoid rotation interference with the shooting. After the character wheel 2 is stable, the MCU controls the camera 5 through the SPI interface to capture the complete image of the character wheel group. The image is transmitted to the OCR recognition module via the SPI bus. The OCR module preprocesses the image and recognizes the numbers. It splices the images into a complete mechanical reading according to the arrangement order of the character wheels 2 and feeds it back to the MCU through the UART interface. The MCU calculates the difference between the mechanical reading and its own accumulated electronic count value. If the absolute value of the deviation is ≤1kWh, it is considered normal. If it exceeds 1kWh, an abnormal alarm is triggered.

[0037] The counter supports two reading methods to meet different usage needs: On-site reading: Operators can directly read the mechanical display numbers of all digit wheels 2 through the high-transmittance PC material observation window on the counter housing, which is convenient for on-site inspection and verification; Remote reading: The MCU integrates the calibrated mechanical readings, electronic counter values ​​and other data, and controls the NBIoT wireless communication module through the UART interface to remotely transmit standardized data to the background management system to achieve real-time monitoring and data traceability; It can also trigger the camera 5 to capture and recognize images as needed to remotely obtain instant readings.

[0038] When the calibration detects that the reading deviation exceeds the standard, the MCU immediately sends an alarm message to the background management system through the NBIoT module to remind the staff to troubleshoot the fault.

[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mechanical counter for a remote-reading electricity meter, comprising a counter housing (1) and a digit wheel assembly rotatably mounted inside the counter housing (1), characterized in that: The character wheel group consists of multiple coaxially arranged character wheels (2). The circumferential surface of the individual character wheel (2) is uniformly surrounded by ten sets of preset white scale lines (3). The white scale lines (3) are coated with infrared reflective coating. The remaining area of ​​the individual character wheel (2) and the entire area of ​​the remaining character wheels (2) are coated with infrared absorbent coating. The counter housing (1) is equipped with an infrared sensing module corresponding to the installation position of the individual character wheel (2). The counter housing (1) is also equipped with a verification remote transmission unit.

2. The mechanical counter of a remote transmission meter according to claim 1, characterized in that, The infrared sensing module consists of an active infrared sensor (4), an infrared driving module, a signal amplification module, and a shaping module. The infrared driving module is electrically connected to the transmitting end of the active infrared sensor (4). The signal output end of the receiving end of the active infrared sensor (4) is connected to the signal amplification module. The signal amplification module is electrically connected to the shaping module.

3. The mechanical counter of a remote transmission meter according to claim 2, characterized in that, The active infrared sensor (4) has its transmitting and receiving axes intersecting at the white scale line (3) along its rotation trajectory.

4. The mechanical counter of a remote transmission meter according to claim 2, characterized in that, The verification remote transmission unit integrates an MCU main control module, a camera (5), an OCR recognition module, and an NBIoT wireless communication module. The MCU main control module is connected to the shaping module and is connected to the OCR recognition module and the NBIoT wireless communication module respectively. The camera (5) is connected to the MCU main control module.

5. The mechanical counter of a remote transmission meter according to claim 4, characterized in that, The camera (5) is fixedly installed on the housing of the verification remote transmission unit. The lens of the camera (5) faces the digital display surface of the character wheel (2) and the shooting range covers the digital display area of ​​all the character wheels (2).

6. The mechanical counter of a remote transmission meter according to claim 4, characterized in that, The receiving end of the active infrared sensor (4) outputs a jump signal. The jump signal is amplified by the signal amplification module and then converted into a standard TTL pulse signal by the shaping module. The MCU main control module captures the TTL pulse signal and calculates the electronic count value based on the formula: pulse number × 0.1kWh = electronic count value.

7. The mechanical counter of a remote transmission meter according to claim 6, characterized in that, The camera (5) captures the image of the character wheel group and transmits it to the OCR recognition module. The OCR recognition module extracts the displayed numbers of each character wheel (2) and splices them together according to the arrangement order of the character wheels (2) to obtain the mechanical reading. The OCR recognition module transmits the mechanical reading to the MCU main control module. The MCU main control module performs a difference calculation between the mechanical reading and the electronic counting value. When the absolute value of the deviation exceeds 1kWh, an abnormal alarm mechanism is triggered.

8. The mechanical counter of a remote transmission meter according to claim 7, characterized in that, The counter housing (1) has an observation window on the surface corresponding to the digital display area of ​​the character wheel group. The observation window is made of transparent PC material and the viewing area completely covers the digital display surface of all character wheels (2).

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