Novel photoelectric direct-reading water meter

Abstract

The utility model relates to a novel photoelectric direct-reading water meter, and relates to the technical field of meters. The novel photoelectric direct-reading water meter comprises a main control module, an SPAD module, a selection logic module, an identification module, an indicating lamp and a character wheel. Through reflection bar codes corresponding to different numbers on a character wheel and a multi-path current detection circuit in an SPAD module, based on an SPAD dot matrix formed by SPAD diodes in the multi-path current detection circuit, an avalanche effect and a reset function of the SPAD diodes, and in combination with a selection logic module and an identification module, accurate identification of the numbers on the character wheel can be completed by using natural light, and the identification accuracy is improved. A light-emitting element and a light guide groove structure are prevented from being installed in the water meter, so that the water meter is simple in structure.

Description

Technical Field

[0001] The utility model relates to the technical field of meters, in particular to a novel photoelectric direct-reading water meter. Background Art

[0002] The statements herein merely provide background art related to the present invention and do not necessarily constitute prior art.

[0003] As a smart water meter, the photoelectric direct-reading water meter not only improves the efficiency of water management through monitoring, meter reading and metering functions, but also can achieve accurate measurement, avoid waste caused by inaccurate data, and promote water conservation and environmental protection.

[0004] The existing photoelectric direct-reading water meter sets a light-emitting element and a photosensitive element on both sides of each set of character wheels, uses the light-emitting element as a light source, and sets a matching light-guiding groove to read the numbers on the character wheels. However, this method makes the internal structure of the water meter and the process of reading the numbers on the character wheels more complicated; and the photoelectric direct-reading water meter can only read the numbers on the character wheels when the light-emitting element is emitting light, which leads to the problem of being unable to read because the light-emitting element cannot emit light. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide a novel photoelectric direct-reading water meter. By setting up a SPAD dot matrix, it is unnecessary to set up a light-emitting element and a light-guiding groove in the water meter, so that the numbers on the character wheel can be accurately read, making the internal structure of the water meter and the process of reading the numbers on the character wheel relatively simple.

[0006] The purpose of the utility model is to provide a novel photoelectric direct-reading water meter, including a main control module, a SPAD module, a selection logic module, an identification module, an indicator light and a character wheel;

[0007] Reflective barcodes of different shapes are printed on different numbers of the character wheel. The SPAD module includes multiple parallel current detection circuits, each of which includes a SPAD diode, an amplifier, a discriminator, a counter and a digital-to-analog converter connected in sequence. The SPAD diode is used to receive light reflected by the reflective barcode on the character wheel. The SPAD diodes in the multiple current detection circuits together constitute a SPAD dot matrix; the digital-to-analog converter is connected to the main control module, the selection logic module, the identification module and the indicator light are all connected to the main control module, and the selection logic module is connected to the identification module.

[0008] As a further technical solution, the photoelectric direct-reading water meter also includes a power module, which is connected to the main control module, the indicator light and the SPAD diode in the SPAD module.

[0009] As a further technical solution, the selection logic module is specifically a row and column selection logic circuit.

[0010] As a further technical solution, the identification module is specifically a voltage comparison circuit.

[0011] As a further technical solution, the photoelectric direct-reading water meter also includes a storage module, and the storage module is connected to the main control module.

[0012] As a further technical solution, the storage module is specifically a RAM memory.

[0013] As a further technical solution, the photoelectric direct-reading water meter also includes a communication module, and the communication module is connected to the main control module.

[0014] As a further technical solution, the communication module is also connected to the mobile terminal via Wifi.

[0015] As a further technical solution, the mobile terminal is specifically a smart phone or a computer.

[0016] As a further technical solution, the communication module is also connected to a remote meter reading system via Bluetooth.

[0017] Beneficial effects of one or more of the above technical solutions:

[0018] The utility model uses the reflective barcodes corresponding to different numbers on the character wheel and the multi-channel current detection circuit in the SPAD module, and based on the SPAD dot matrix composed of SPAD diodes in the multi-channel current detection circuit, the avalanche effect and reset function of the SPAD diode, and combines the selection logic module and the identification module, so that natural light can be used to complete the accurate recognition of the numbers on the character wheel, avoiding the installation of light-emitting elements and light-guiding groove structures in the water meter, and making the structure of the water meter simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings in the specification that constitute a part of this application are used to provide further understanding of the present application. In order to facilitate understanding, the proportions between the structures of each part are adjusted. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute a limitation on the present application.

[0020] Figure 1 This is the overall structural diagram of a new type of photoelectric direct-reading water meter of the utility model.

[0021] Figure 2 It is a structural diagram of a single current detection circuit in the SPAD module of the utility model.

[0022] Figure 3 It is a schematic diagram of a SPAD dot matrix composed of SPAD diodes in the utility model.

[0023] Figure 4 This is a circuit schematic diagram of the SPAD diode of the utility model.

[0024] Figure 5 This is a logic schematic diagram for selecting a logic module in the present utility model.

[0025] Figure 6 It is a schematic diagram of voltage comparison in the identification module of the present utility model.

[0026] Among them, 1. main control module, 2. SPAD module, 2-1. SPAD diode, 2-2. amplifier, 2-3. discriminator, 2-4. counter, 2-5. digital-to-analog converter, 3. selection logic module, 4. identification module, 5. indicator light, 6. power module, 7. communication module, 8. storage module, 9. mobile terminal, 10. remote meter reading system. DETAILED DESCRIPTION

[0027] The following is combined with Figure 1-6 , clearly and completely describe the technical solutions in the embodiments of the utility model.

[0028] Embodiment 1

[0029] Reference Figure 1 A novel photoelectric direct-reading water meter includes a main control module 1, a SPAD module 2, a selection logic module 3, an identification module 4, an indicator light 5, a power module 6 and a character wheel.

[0030] In this embodiment, the character wheel includes numbers 0-9, and each number is pasted with a reflective barcode of different shapes, and the reflective barcode is used to reflect natural light. The power module 6 uses a 24V battery.

[0031] Reference Figure 2 , the SPAD module 2 includes multiple parallel current detection circuits, and each current detection circuit includes a SPAD diode 2-1, an amplifier 2-2, a discriminator 2-3, a counter 2-4 and a digital-to-analog converter 2-5 connected in sequence. Among them, the SPAD diode 2-1 in each current detection circuit is connected to the power module 6, and the digital-to-analog converter 2-5 is connected to the main control module 1. Among them, the SPAD diode 2-1 is used to receive the light reflected by the reflective barcode on the character wheel.

[0032] At the same time, the SPAD diodes 2-1 in each current detection circuit together form a SPAD matrix. Figure 3 , is a SPAD dot pattern designed for water meters with a character wheel group consisting of three character wheels, each of which contains the numbers 0-9.

[0033] in, Figure 3 The SPAD diodes 2-1 numbered 1-5 are used to mark the numbers 0-9 on the first character wheel, the SPAD diodes 2-1 numbered 6-10 are used to mark the numbers 0-9 on the second character wheel, and the SPAD diodes 2-1 numbered 11-15 are used to mark the numbers 0-9 on the third character wheel. The number of SPAD diodes 2-1 and the SPAD dot pattern can be adaptively adjusted according to the number of character wheel groups.

[0034] At the same time, since it is necessary to accurately read the numbers on the character wheel through the SPAD dot pattern, it is necessary to achieve alignment between the SPAD diode 2-1 in the SPAD dot pattern and the numbers on the character wheel. In this embodiment, the alignment between the SPAD diode 2-1 and the numbers on the character wheel is completed through the binomial coefficient.

[0035] Specifically, Figure 3 The SPAD diodes 2-1 and the first character wheel numbered 1-5 are described in detail.

[0036] Table 1

[0037]

[0038] Based on the binomial coefficient ( ) and the corresponding relationship shown in Table 1 is obtained; the above relationship can be understood as follows: when the number 0 is displayed on the first character wheel, the natural light received by the reflective barcode on the number 0 is reflected to the SPAD diodes 2-1 numbered 1 and 2. In the above manner, when different numbers are displayed on the character wheel, two SPAD diodes 2-1 receive the natural light reflected by the reflective barcode, and the two SPAD diodes 2-1 corresponding to different numbers are not exactly the same.

[0039] Through the above method, the alignment relationship between the SPAD diode 2-1 in the SPAD dot matrix and the numbers on all the character wheels in the character wheel group is achieved.

[0040] There is no requirement for the shape of the reflective barcode pasted on the character wheel; the pattern of the SPAD dot matrix can be predicted and calculated by establishing a mathematical model and simulation of the optical path to predict and calculate the behavior of the optical signal when passing through the SPAD dot matrix pattern, ensuring that the position, size and shape of each SPAD diode 2-1 can accurately control the propagation path of the light, maximize the transmission efficiency of the optical signal, and make the SPAD dot matrix pattern have high performance and high reliability in optical encoding, data capture and transmission, thereby significantly improving the accuracy of the water meter. The above description is only one way to design the SPAD dot matrix pattern, the purpose of which is to ensure that the SPAD diode 2-1 can receive the light reflected by the reflective barcode on the character wheel; and the pattern of the SPAD dot matrix formed by the SPAD diode 2-1 can be adaptively adjusted.

[0041] Reference Figure 4 , the SPAD diode 2-1 used in this embodiment is a single-photon avalanche diode; when a photon irradiates the SPAD diode 2-1, the photocurrent of the SPAD diode 2-1 becomes larger and exceeds the steady-state current threshold, which will produce an avalanche effect. If the avalanche effect is not controlled, excessive avalanche current will be generated, which may cause damage to the SPAD diode 2-1 or degradation of its performance. In order to enable the SPAD diode 2-1 to quickly return to its initial state after the avalanche so as to detect the photon again, quenching measures need to be taken. By increasing the Rq resistor, the reset time is adjusted; when the avalanche current flows through the Rq resistor, the voltage across the SPAD diode 2-1 is reduced, thereby suppressing the avalanche effect and achieving the effect of quenching and resetting, which is convenient for detecting the next photon.

[0042] This embodiment is based on the SPAD diode 2-1 and the SPAD dot matrix pattern composed of the SPAD diode 2-1, so that when the numbers on the character wheel are exposed to natural light, based on the different reflective barcodes bonded to different numbers on the character wheel, the natural light is reflected to the corresponding SPAD diode 2-1, and the subsequent identification and reading of the numbers are completed through the SPAD diode 2-1, so there is no need to install light-emitting elements and light guide grooves in the water meter, and it can be achieved only by irradiation with natural light, so that the structure inside the water meter will be relatively simple.

[0043] At the same time, during the use of the SPAD diode 2-1, in addition to the avalanche effect caused by light, conditions such as high temperature may also cause the avalanche effect of the SPAD diode 2-1. Therefore, it is necessary to identify and screen the generated photocurrent to obtain the photocurrent caused by light.

[0044] And refer to Figure 2When the SPAD diode 2-1 generates photocurrent, the current signal will be amplified by the amplifier 2-2 first, and then the current signal will be screened by the discriminator 2-3; wherein, the discriminator 2-3 can screen the photocurrent according to the preset threshold, thereby eliminating the background noise and the photocurrent caused by other reasons, and only retain the photocurrent caused by the photons. The photocurrent processed by the discriminator 2-3 passes through the counter 2-4, thereby realizing the counting of the number of photons, and finally converted into an analog signal by the digital-to-analog converter 2-5 and transmitted to the main control module 1.

[0045] Through the above process, the SPAD diode 2-1 in each current detection circuit in the SPAD module 2 will give a signal to the main control module 1 after being illuminated. The photoelectric direct-reading water meter also includes a storage module 8, which is connected to the main control module 1. In this embodiment, the storage module 8 uses a RAM memory; and after the main control module 1 receives the signal transmitted by the SPAD module 2, it can first save the signal through the storage module 8, which is conducive to retaining the original signal data, and in the event of a fault, it is conducive to fault identification and maintenance of the SPAD module 2.

[0046] Meanwhile, after receiving the signal transmitted by the SPAD module 2 , the main control module 1 cannot recognize the numbers on the character wheel; therefore, the signal transmitted by the SPAD module 2 needs to be classified and recognized first.

[0047] Reference Figure 1 and Figure 5 , the selection logic module 3 and the identification module 4 are both connected to the main control module 1, and the selection logic module 3 and the identification module 4 are also connected.

[0048] After receiving the current signal transmitted by the SPAD module 2, the main control module 1 transmits the signal to the selection logic module 3, thereby screening a large number of signals. In this embodiment, the selection logic module 3 uses a row and column selection logic circuit to screen the signal, which is consistent with the SPAD dot matrix pattern composed of the SPAD diode 2-1.

[0049] Specifically, in the row and column selection logic circuit, the signal is first column-selected to filter out which column each signal belongs to, that is, each signal corresponds to which word wheel in the word wheel group; then the row selection is performed to filter out which SPAD diode 2-1 the signal corresponds to. In the above manner, the two SPAD diodes 2-1 corresponding to the numbers on each word wheel can be determined, thereby realizing signal screening and division. Figure 5 This is a logic principle diagram of a row and column selection logic circuit. The specific row and column selection logic circuit can be adaptively selected according to the number of character wheels in the character wheel group.

[0050] Reference Figure 6 After the signal screening by the selection logic module 3, the two current signals representing the same character wheel are transmitted to the identification module 4. In this embodiment, the identification module 4 adopts a voltage comparison circuit, and before the voltage comparison, a high-precision low-temperature drift sampling resistor is connected to convert the current signal into a voltage signal and perform voltage comparison. In the comparison process, by comparing the two voltage signals corresponding to the same character wheel with the threshold voltage, when the voltages of the two signals are greater than the threshold voltage, a signal is given to the main control module 1.

[0051] Among them, the threshold voltage mentioned is the voltage corresponding to the photocurrent generated when the SPAD diode 2-1 undergoes an avalanche reaction; in this way, the numbers on the character wheel can be accurately identified through the SPAD diode 2-1, ensuring that the numbers on the character wheel can be accurately identified even when the character wheel rotates too fast.

[0052] In the above manner, when the identification module 4 gives a signal to the main control module 1, it means that the two SPAD diodes 2-1 have received light, so that the numbers on the character wheel can be accurately identified, thereby completing the accurate reading of the numbers on the character wheel in the entire character wheel group. At the same time, after the numbers on the character wheel are accurately identified, the results can be saved by the storage module 8, and can be compared with the original signal later, so as to inspect and maintain the circuit or water meter structure.

[0053] Finally, since there is no need to continuously power the light-emitting element through the power module 6, the battery life of the power module 6 in the water meter is also correspondingly improved.

[0054] Through the above method, there is no need to install light-emitting elements and light guide grooves in the water meter, and the numbers on the character wheel can be accurately read only by natural light; and considering that there is a need to read the meter at night; for this reason, the indicator light 5 is connected to the main control module 1, and the indicator light 5 can provide a corresponding light source; and the indicator light 5 can also be used to remind when a fault occurs. At the same time, the power module 6 is also connected to the main control module 1 and the indicator light 5 to realize power supply to the main control module 1 and the indicator light 5. In this embodiment, the indicator light 5 adopts an LED lamp.

[0055] Reference Figure 1The photoelectric direct-reading water meter also includes a communication module 7; the communication module 7 is connected to the mobile terminal 9 via Wifi, and is also connected to the remote meter reading system 10 via Bluetooth. After the main control module 1 obtains the reading result, it can be transmitted to the mobile terminal 9 such as a smart phone or a computer, so that the user can always understand the water use situation. At the same time, the result can also be transmitted to the remote meter reading system 10 for meter reading records. In this way, not only the efficiency of water management is improved, but also the waste problem caused by inaccurate data is avoided, and water resource conservation and environmental protection are promoted.

[0056] At the same time, there is no requirement for the installation position of each module in the water meter. It can be adaptively set as long as the above functions can be completed.

[0057] Although the above describes the specific implementation methods of the utility model in combination with the accompanying drawings, it is not intended to limit the scope of protection of the utility model. Technical personnel in the relevant field should understand that on the basis of the technical solution of the utility model, various modifications or deformations that can be made by technical personnel in this field without creative work are still within the scope of protection of the utility model.

Claims

1. A new type of photoelectric direct reading water meter, characterized in that: It includes a main control module, a SPAD module, a selection logic module, an identification module, an indicator light and a character wheel; Reflective barcodes of different shapes are printed on different numbers of the character wheel. The SPAD module includes multiple parallel current detection circuits, each of which includes a SPAD diode, an amplifier, a discriminator, a counter and a digital-to-analog converter connected in sequence. The SPAD diode is used to receive light reflected by the reflective barcode on the character wheel. The SPAD diodes in the multiple current detection circuits together constitute a SPAD dot matrix; the digital-to-analog converter is connected to the main control module, the selection logic module, the identification module and the indicator light are all connected to the main control module, and the selection logic module is connected to the identification module.

2. A novel photoelectric direct-reading water meter as claimed in claim 1, characterized in that: The photoelectric direct-reading water meter also includes a power module, which is connected to the main control module, the indicator light and the SPAD diode in the SPAD module.

3. A novel photoelectric direct-reading water meter as claimed in claim 1, characterized in that: The selection logic module is specifically a row and column selection logic circuit.

4. A novel photoelectric direct-reading water meter as claimed in claim 1, characterized in that: The identification module is specifically a voltage comparison circuit.

5. A novel photoelectric direct-reading water meter as claimed in claim 1, characterized in that: The photoelectric direct-reading water meter also includes a storage module, and the storage module is connected to the main control module.

6. A novel photoelectric direct-reading water meter as claimed in claim 5, characterized in that: The storage module is specifically a RAM memory.

7. A novel photoelectric direct-reading water meter as claimed in claim 1, characterized in that: The photoelectric direct-reading water meter also includes a communication module, and the communication module is connected to the main control module.

8. A novel photoelectric direct-reading water meter as claimed in claim 7, characterized in that: The communication module is also connected to the mobile terminal via Wifi.

9. A novel photoelectric direct-reading water meter as claimed in claim 8, characterized in that: The mobile terminal is specifically a smart phone or a computer.

10. A novel photoelectric direct-reading water meter as claimed in claim 7, characterized in that: The communication module is also connected to the remote meter reading system via Bluetooth.

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