M-Bus communication data interaction module and intelligent gas meter thereof

Abstract

The utility model discloses an M-Bus communication data interaction module and an intelligent gas meter thereof. The M-Bus communication data interaction module comprises a microcontroller, an M-Bus sending module and an M-Bus receiving module, the microcontroller is used for data acquisition, data processing and communication control, the microcontroller is connected to the flow sensor, the flow sensor can measure the flow of gas passing through the gas meter, convert analog signals of the flow into digital signals and transmit the digital signals to the microcontroller, and the microcontroller is connected with the M-Bus sending module and the M-Bus receiving module. The M-Bus transmitting module is used for converting a serial port signal output by the microcontroller into a level signal and transmitting the signal to an M-Bus network, and the M-Bus receiving module is used for receiving a signal from the M-Bus network and converting the signal into a serial port signal which can be identified by the microcontroller. The M-Bus communication data interaction module is applied to the intelligent gas meter. The M-Bus communication data interaction module and the intelligent gas meter thereof have the following beneficial effects that the M-Bus communication data interaction module and the intelligent gas meter thereof have the characteristics of few connecting wires, low installation and maintenance difficulty and strong reliability.

Description

Technical Field

[0001] The utility model relates to an M-Bus communication data interaction module and an intelligent gas meter thereof. Background Art

[0002] The microcontroller of an existing smart gas meter usually uses RS-485 communication, which is generally a four-wire system, namely, VCC, GND, TX, and RX. The smart gas meter transmits the reading data to a concentrator or data collector for remote monitoring and management.

[0003] Since gas meters are usually installed in special locations such as users' homes or basements, when there are many connecting wires, the failure rate is high and the installation time is long, making subsequent maintenance inconvenient.

[0004] Moreover, the installation of a gas meter usually takes 20-30 minutes. Reducing wiring can shorten the installation time. In addition, when installing the gas meter, the air inlet and outlet pipes on the top of the gas meter need to be sealed and connected to the natural gas pipeline, which further prolongs the installation time and is more cumbersome and inconvenient. Utility Model Content

[0005] The utility model aims to provide an M-Bus communication data interaction module, which has the characteristics of less connecting wires, low installation and maintenance difficulty and high reliability.

[0006] The above technical objectives of the utility model are achieved through the following technical solutions:

[0007] An M-Bus communication data interaction module comprises a microcontroller, an M-Bus sending module and an M-Bus receiving module. The microcontroller is used for data acquisition, processing and communication control. The microcontroller is connected to a flow sensor. The flow sensor can measure the flow of gas passing through a gas meter and convert its analog signal into a digital signal and transmit it to the microcontroller. The M-Bus sending module converts the serial port signal output by the microcontroller into a level signal and sends the signal to the M-Bus network. The M-Bus receiving module receives the signal from the M-Bus network and converts it into a serial port signal recognizable by the microcontroller.

[0008] The utility model is further configured as follows: the M-Bus sending module includes: a voltage stabilizer for providing a stable M-Bus voltage; a first NPN transistor and a second NPN transistor for signal amplification and control; a plurality of resistors for current limitation and voltage division; an input signal port MBUS_TX for receiving a serial port signal from a microcontroller; and an output signal port 0MBUS+ for outputting a level signal connected to an M-Bus network.

[0009] The utility model is further configured as follows: the base of the first NPN transistor is connected to the input signal port MBUS_TX through a resistor, the collector is connected to the base of the second NPN transistor, the emitter of the second NPN transistor is connected to the ground, and the collector is connected to the output signal port 0MBUS+.

[0010] The utility model is further configured as follows: the M-Bus receiving module includes: a PNP transistor for signal amplification and control; a third NPN transistor and a fourth NPN transistor for signal amplification and control; a plurality of resistors for current limitation and voltage division; a diode for power isolation; a Zener diode for voltage clamping protection; an input power port +AV for receiving power supply voltage; and an output signal port RXD1 for outputting the received M-Bus signal to a microcontroller.

[0011] The utility model is further configured as follows: the base of the PNP transistor is connected to the clamping voltage of the voltage regulator, the emitter is connected to the input power port +AV, and the collector is connected to the ground; the base of the third NPN transistor is connected to the collector of the PNP transistor, the collector is connected to the base of the fourth NPN transistor, the emitter of the fourth NPN transistor is connected to the ground, and the collector is connected to the output signal port RXD1.

[0012] Another object of the utility model is to provide an intelligent gas meter using an M-Bus communication data interaction module, which has the characteristics of saving installation time and improving installation efficiency.

[0013] The above technical objectives of the utility model are achieved through the following technical solutions:

[0014] A smart gas meter comprises a meter body, a display screen, a battery box, an air inlet and an air outlet. The meter body is provided with a display screen, the bottom of the meter body is provided with a battery box for loading batteries for power supply, and the top of the meter body is provided with an air inlet and an air outlet.

[0015] The utility model is further configured as follows: the air inlet and the air outlet are respectively connected to the natural gas pipeline and are provided with threads on the surface; the air inlet and the air outlet are sleeved with rubber rings, which are used to play a role of extrusion sealing when connecting the natural gas pipeline.

[0016] The utility model is further configured as follows: a connection seat with an M-Bus interface is arranged on the back side of the meter body, a line inlet slot is arranged on the top of the connection seat, a protective cover is arranged on the outer side of the connection seat, and a matching hole corresponding to the line inlet slot is arranged on the protective cover.

[0017] The utility model is further configured as follows: a fixing seat is arranged below the connecting seat, a mounting hole is arranged on the fixing seat, and a spring is arranged in the mounting hole.

[0018] In summary, the utility model has the following beneficial effects: the M-Bus communication data interaction module and the smart gas meter thereof have the characteristics of fewer connecting wires, low difficulty in installation and maintenance, and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of the M-Bus communication data interaction module;

[0020] Figure 2 This is the circuit diagram of the M-Bus sending module;

[0021] Figure 3 This is the circuit diagram of the M-Bus receiving module;

[0022] Figure 4 It is a structural schematic diagram of a smart gas meter;

[0023] Figure 5 for Figure 4 A rear view structural diagram of ;

[0024] Figure 6 for Figure 5 Exploded view of.

[0025] Figure numerals: 1. meter body; 2. display screen; 3. battery box; 4. air inlet; 5. air outlet; 6. thread; 7. rubber ring; 8. connecting rod; 9. ring; 10. column; 11. connecting seat; 12. wire inlet groove; 13. protective cover; 14. matching hole; 15. fixing seat; 16. mounting hole; 17. spring. DETAILED DESCRIPTION

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "page", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0028] In the description of the present utility model, "multiple" means two or more than two, unless otherwise clearly specified and specifically defined. In the present utility model, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances.

[0029] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0030] like Figure 1 As shown, an M-Bus communication data interaction module includes a microcontroller (single-chip microcomputer) for data acquisition, processing and communication control, and the microcontroller is connected to a flow sensor. The flow sensor can measure the flow of gas through the gas meter, and convert its analog signal into a digital signal and transmit it to the microcontroller, which is debugged and processed into a serial port signal by the microcontroller.

[0031] The microcontroller is coupled with an M-Bus sending module and an M-Bus receiving module. The M-Bus sending module converts the serial port signal output by the microcontroller into a level signal and sends its signal to the M-Bus network. The M-Bus network collects the data of each gas meter M-Bus substation and transmits it to the concentrator, which returns the processed data information to the M-Bus network. The M-Bus receiving module receives the signal from the M-Bus network and converts it into a serial port signal recognizable by the microcontroller, processes the serial port signal and converts it into the original gas reading data, thereby completing the communication data interaction.

[0032] The M-Bus sending module is described in detail below.

[0033] like Figure 2 The circuit diagram of the M-Bus starter module is shown below, where the components are as follows:

[0034] U2 (LM317L / C75510): voltage regulator, used to provide a stable M-Bus voltage.

[0035] Q3 (BC817): NPN transistor, used for signal amplification and control.

[0036] Q4 (BC817): NPN transistor, used for signal amplification and control.

[0037] R1, R20, R21, R23, R36: Resistors, used for current limiting and voltage division.

[0038] MBUS_TX: Input signal, coming from the microcontroller or data source.

[0039] 0MBUS+: Output signal, connected to the M-Bus network.

[0040] VCC3.3: 3.3V power supply.

[0041] VCC-40V: 40V power supply.

[0042] Among them, the left end of the resistor R36 is connected to the TX end of the microcontroller, and the TX end inputs the serial port signal.

[0043] 1. The serial port signal sent by the TX end is high level

[0044] MBUS_TX signal is applied to the base of transistor Q4 through R36, and the base voltage of transistor Q4 rises and is higher than the voltage of the emitter (E), so that the emitter (E) and collector (C) of transistor Q4 are connected to ground, and the collector voltage of transistor Q4 is pulled down to close to the ground potential, that is, low level;

[0045] The base of transistor Q3 is connected to the collector of transistor Q4, so that the base voltage of Q3 is also at a low level;

[0046] The base voltage of transistor Q3 is lower than the emitter voltage, and Q3 is cut off. At this time, the output voltage of 0MBUS+ is maintained at the voltage provided by the voltage regulator U2, which is calculated to be 35.84V.

[0047] 2. The serial port signal sent by the TX end is low level

[0048] MBUS_TX signal is applied to the base of transistor Q4 through R36. The base of transistor Q4 is also at a low level, which is lower than the emitter (E) voltage, so that the emitter (E) and collector (C) of transistor Q4 are cut off and disconnected. The collector end of transistor Q4 is connected to the power supply VCC3.3, so that the collector voltage is pulled up to 3.3V, which is a high level.

[0049] The base of transistor Q3 is connected to the collector of transistor Q4, so that the base voltage of Q3 is high level;

[0050] The base voltage of transistor Q3 is greater than the emitter voltage, and the emitter and collector of Q3 are turned on. At this time, the output voltage of 0MBUS+ is pulled down to form a low-level signal. At this time, the output voltage of the adjustable integrated regulator U2 is 23.84V.

[0051] As described above, the level of the serial port signal input through the TX end is different, so that the level signal output by 0MBUS+ also changes accordingly.

[0052] When the TX terminal is input at a high level, the output of the corresponding adjustable integrated voltage regulator is 35.84V;

[0053] When the TX end inputs a low level, the output end of the corresponding adjustable integrated regulator is 23.34V.

[0054] The M-Bus receiving module is described in detail below.

[0055] The 0MBUS+ output signal is sent to the M-Bus network and the data information is processed by the concentrator and then returned to the M-Bus receiving module.

[0056] like Figure 3 The circuit diagram of the M-Bus receiver module is shown below, where the circuit components are as follows:

[0057] Q2 (MMBT5401): PNP transistor, used for signal amplification and control.

[0058] Q3, Q4 (MMBT5551): NPN transistors, used for signal amplification and control.

[0059] R2, R5, R7, R10, R11, R17, R18, R19, R20, R23: Resistors, used for current limiting and voltage division.

[0060] D3: Diode, used for power isolation and to prevent reverse current.

[0061] D8 (ZM4750A): 27V voltage regulator, connected between +V and ground, used to clamp +V at 27V.

[0062] +AV, +V: power supply.

[0063] VCC3.3: 3.3V power supply.

[0064] RXD1: Received M-Bus signal output, sent to the microcontroller.

[0065] 1. The voltage detected at the receiving end V+ is 23.34V.

[0066] When +V is 23.34V, it is lower than the clamping voltage of the voltage regulator D8, so that the base and emitter voltages of the transistor Q2 remain consistent without voltage difference. Q2 is cut off and the base of the transistor Q3 is connected to the collector of Q2 through R19, so the base voltage of Q3 is 23.34V.

[0067] The emitter of Q3 is grounded, and the base voltage is higher than the turn-on voltage, so that Q3 is turned on. When Q3 is turned on, it is grounded, so that the collector voltage of Q3 is close to the ground potential and is at a low level.

[0068] The base of transistor Q4 is connected to the collector of Q3 through R23. Since the collector voltage of Q3 is at a low level, the base voltage of Q3 is also close to a low level, and Q4 is cut off.

[0069] When Q4 is open, the voltage of VCC3.3 is raised to 3.3V, which is a high level, making the output level of RXD1 a high level.

[0070] 2. The voltage detected by the receiving end +V is 35.84V.

[0071] When +V is 35.84V, which is higher than 27V of Zener diode D8, D8 is turned on and +V is clamped at 27V. At this time, the emitter of Q2 is connected to +AV, and the voltage of +AV is consistent with the original +V voltage, which is 35.84V, while the base voltage of Q2 is clamped at 27V, so that there is a voltage difference between the emitter and base of Q2, and Q2 is turned on.

[0072] Since the collector of Q2 is grounded, Q2 is turned on and the ground is close to the ground potential, which is a low level.

[0073] The base of Q3 is also at a low level. Q3 is cut off and disconnected, so that the collector of Q3 is raised to 3.3V under the action of VCC3.3, which is a high potential.

[0074] The base of Q4 is also at a high level, so that Q4 is turned on. Since the emitter of Q4 is grounded, the voltage of Q4 is close to the ground potential and is at a low level. At this time, the output level of RXD1 is at a low level.

[0075] As described above, by detecting the difference in V+ voltage, the output level signal of RXD1 also changes accordingly.

[0076] When the detection voltage of V+ is 35.84V, RXD1 outputs a low level (close to 0V);

[0077] When the detection voltage of V+ is 23.34V, RXD1 outputs a high level (3.3V).

[0078] In summary:

[0079] When the TX end inputs a high level, the output of the corresponding adjustable integrated voltage regulator is 35.84V, and the RX end outputs a low level;

[0080] When the TX end inputs a low level, the output end of the corresponding adjustable integrated regulator is 23.34V, and the RX end outputs a high level.

[0081] The above two-wire serial port data interaction mode complies with the anti-phase relationship of the serial port communication standard and meets the requirements, so that the above circuit can complete the two-wire serial port data interaction.

[0082] Under the above settings, the four-wire system required for traditional RS-485 communication is transformed into the two-wire system (VCC, GND) of M-Bus, which reduces the complexity of wiring, matches the occasions with limited installation space such as gas meters, simplifies maintenance work, reduces labor costs and the possibility of errors, and the overall connection and interaction are carried out through twisted pair cables, and the combination of voltage regulator tubes and triodes ensures the stability and reliability of signal transmission. By adjusting the voltage to express the sending and receiving signals, it matches different power supply voltage requirements and has good adaptability.

[0083] like Figure 4 , Figure 5 , Figure 6 As shown, the present application also provides an intelligent Energy gas meter , comprising a watch body 1. A display screen 2 is arranged on the watch body 1, and a battery box 3 is arranged at the bottom of the watch body 1 for loading batteries for power supply.

[0084] The top of the meter body 1 is provided with an air inlet 4 and an air outlet 5. The air inlet 4 and the air outlet 5 are respectively connected to the natural gas pipeline and are provided with threads 6 on the surface. The air inlet 4 and the air outlet 5 can be sealed and connected to the natural gas pipeline through nuts later.

[0085] The air inlet 4 and the air outlet 5 are sleeved with a rubber ring 7. The rubber ring 7 is used to squeeze and seal when connecting the natural gas pipeline to prevent gas leakage.

[0086] The two rubber rings 7 are connected to a connecting rod 8. A collar 9 is fixedly arranged in the middle of the connecting rod 8. The collar 9 is sleeved on a column 10, and the column 10 is fixedly connected to the meter body 1.

[0087] A connection base 11 with an M-Bus interface is provided on the back of the meter body 1. A wire inlet slot 12 is provided on the top of the connection base 11. A protective cover 13 is fixedly provided on the outer side of the connection base 11 by the collar 9. The protective cover 13 is slidably provided on the outer side of the connection base 11. A matching hole 14 corresponding to the wire inlet slot 12 is provided on the protective cover 13.

[0088] Correspondingly, a fixing seat 15 is provided below the connecting seat 11. The fixing seat 15 is fixedly provided outside the meter body 1 and covers the bottom area of ​​the connecting seat 11. The fixing seat 15 is provided with a mounting hole 16, and a spring 17 is provided in the mounting hole 16.

[0089] When the air inlet 4 and the air outlet 5 are connected to the natural gas pipeline, the nut is screwed into the threads 6 of the two. At this time, the rubber ring 7 is squeezed and moved down until it reaches the bottom of the threads 6. Under the above traction, the collar 9 moves down, and then drives the protective cover 13 to move down. The protective cover 13 moves down to squeeze the spring 17, so that the spring 17 is compressed and accumulates elastic potential energy. The protective cover 13 finally moves to abut against the fixing seat 15, completely covering the connecting seat 11, protecting the connecting seat 11 and reducing the corrosion of the metal parts on the connecting seat 11 caused by contact with the external environment.

[0090] When disassembling the gas meter, the nut is unscrewed in the reverse direction. At this time, the protective cover 13 is no longer under pressure. Under the action of the spring 17, the protective cover 13 obtains a reset force for reverse movement, reducing the difficulty of pulling by the staff, thereby achieving the purpose of facilitating the maintenance of the M-Bus interface on the connecting socket 11.

[0091] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. An M-Bus communication data interaction module, characterized in that: It includes a microcontroller, an M-Bus sending module and an M-Bus receiving module. The microcontroller is used for data acquisition, processing and communication control. The microcontroller is connected to a flow sensor. The flow sensor can measure the flow of gas passing through a gas meter and convert its analog signal into a digital signal and transmit it to the microcontroller. The M-Bus sending module converts the serial port signal output by the microcontroller into a level signal and sends its signal to the M-Bus network. The M-Bus receiving module receives the signal from the M-Bus network and converts it into a serial port signal recognizable by the microcontroller.

2. The M-Bus communication data interaction module according to claim 1, characterized in that: The M-Bus sending module includes: A voltage regulator to provide a stable M-Bus voltage; The first NPN transistor and the second NPN transistor are used for signal amplification and control; Multiple resistors for current limiting and voltage division; Input signal port MBUS_TX, used to receive serial port signals from the microcontroller; Output signal port 0MBUS+, used for output level signal connected to M-Bus network.

3. The M-Bus communication data interaction module according to claim 2, characterized in that: The base of the first NPN transistor is connected to the input signal port MBUS_TX through a resistor, the collector is connected to the base of the second NPN transistor, the emitter of the second NPN transistor is connected to the ground, and the collector is connected to the output signal port 0MBUS+.

4. The M-Bus communication data interaction module according to claim 1, characterized in that: The M-Bus receiving module comprises: PNP transistor, used for signal amplification and control; The third NPN transistor and the fourth NPN transistor are used for signal amplification and control; Multiple resistors for current limiting and voltage division; Diode, used for power isolation; Zener diode for voltage clamping protection; Input power port +AV, used to receive power voltage; The output signal port RXD1 is used to output the received M-Bus signal to the microcontroller.

5. The M-Bus communication data interaction module according to claim 4, characterized in that: The base of the PNP transistor is connected to the clamping voltage of the voltage regulator, the emitter is connected to the input power port +AV, and the collector is connected to the ground; the base of the third NPN transistor is connected to the collector of the PNP transistor, the collector is connected to the base of the fourth NPN transistor, the emitter of the fourth NPN transistor is connected to the ground, and the collector is connected to the output signal port RXD1.

6. A smart gas meter, characterized in that: The smart gas meter comprises an M-Bus communication data interaction module as described in any one of claims 1 to 5, wherein the smart gas meter comprises a meter body, a display screen, a battery box, an air inlet and an air outlet, wherein the display screen is arranged on the meter body, the battery box is arranged at the bottom of the meter body for loading a battery for power supply, and the air inlet and the air outlet are arranged at the top of the meter body.

7. The smart gas meter according to claim 6, characterized in that: The air inlet and the air outlet are respectively connected to the natural gas pipeline and are provided with threads on the surface. The air inlet and the air outlet are sleeved with rubber rings, which are used to play a role of extrusion sealing when connecting the natural gas pipeline.

8. The smart gas meter according to claim 6, characterized in that: A connection socket with an M-Bus interface is arranged on the back side of the meter body, a line inlet slot is arranged on the top of the connection socket, a protective cover is arranged on the outer side of the connection socket, and a matching hole corresponding to the line inlet slot is arranged on the protective cover.

9. The smart gas meter according to claim 8, characterized in that: A fixing seat is arranged below the connecting seat, a mounting hole is arranged on the fixing seat, and a spring is arranged in the mounting hole.

Images