A device for detecting the state of city domestic gas pipeline gas

Abstract

The application provides a device for detecting the gas state of a city domestic gas pipeline, comprising a sensor assembly provided with a micro-electro-mechanical system flow sensor and a pressure sensor, a detection flow channel, a base, a rectifying part, a micro-power-consumption motor valve and a control circuit printed circuit board, wherein the rectifying part and the micro-power-consumption motor valve are both installed in the detection flow channel, the sensor assembly is installed on the rectifying part, the base is installed on the detection flow channel, the control circuit printed circuit board is installed on the base, and the sensor assembly and the micro-power-consumption motor valve are both electrically connected with the control circuit printed circuit board.

Description

Technical Field

[0001] This invention relates to the field of urban residential gas pipeline inspection technology, and in particular to a device for detecting the gas status of urban residential gas pipelines. Background Technology

[0002] In the current global urban gas usage landscape, gas safety remains a significant unresolved issue. Currently, the vast majority of residential gas metering devices utilize mechanical metering technology dating back nearly 200 years, which does not address safety monitoring. Recent residential gas alarms employ oxide sensors, whose sensitivity depends entirely on the surface material. However, kitchen grease and dust easily cover the sensor surface, causing its sensing function to quickly fail after installation. This fails to solve the usage problem and instead increases unnecessary costs.

[0003] While it is theoretically feasible to measure micro-leaks in gas using differential pressure measurement, in practice, due to the extremely high requirements for pressure loss in residential gas pipelines, the limited length of the built-in pipe in the measuring equipment, the inconvenience of setting up pressure loss structures inside the measuring tube, and the extremely small pressure difference, it is impossible to achieve accurate flow detection, let alone detect the minute flow of leaks. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a device for detecting the gas status of urban residential gas pipelines, addressing the shortcomings of the prior art.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A device for detecting the gas status of urban residential gas pipelines, comprising: a sensor assembly equipped with a microelectromechanical system flow sensor and a pressure sensor, a detection channel, a substrate, a rectifier, a low-power motor valve, and a control circuit printed circuit board, wherein the rectifier and the low-power motor valve are both installed in the detection channel, the sensor assembly is installed on the rectifier, the substrate is installed on the detection channel, the control circuit printed circuit board is installed on the substrate, and the sensor assembly and the low-power motor valve are both electrically connected to the control circuit printed circuit board.

[0006] The beneficial effects of adopting the technical solution of this invention are as follows: a flow sensor is used to monitor micro-leakage and flow rates exceeding normal operating conditions in the pipeline; a pressure sensor is used to monitor the pressure status of the pipeline; a temperature sensor is used to measure the safe operating temperature of gas and compensate for the temperature effect of the pressure sensor; and a low-power motor valve is used to actively shut off the upstream gas supply when an abnormal gas condition is detected in the pipeline. By detecting micro-leakage flow, pressure status, and overflow in household gas pipelines, safety accidents during gas use can be avoided. It can measure micro-leakage below the safe leakage level, quickly measure overflow and the safe pressure range of the pipeline, and is equipped with an active safety valve that actively cuts off the gas source when the set safe operating parameters are abnormal, and transmits the abnormal status in real time to the gas data control center and the user's mobile device via a wireless network. This device is suitable for all types of civil gas pipelines and is battery powered, meeting the safety level required for gas equipment. The microelectromechanical heating flow sensor is placed inside the gas pipeline; its small size does not increase pressure loss.

[0007] Furthermore, the microelectromechanical system flow sensor includes: a silicon substrate, a micro heater, an upstream temperature sensor, a downstream temperature sensor, and a temperature sensor. The micro heater, the upstream temperature sensor, the downstream temperature sensor, and the temperature sensor are all mounted on the silicon substrate. The micro heater is located between the upstream temperature sensor and the downstream temperature sensor. A heat insulation cavity is provided on the silicon substrate, and a silicon nitride thin film is provided in the heat insulation cavity. The micro heater, the upstream temperature sensor, and the downstream temperature sensor are all located above the silicon nitride thin film. The micro heater, the upstream temperature sensor, the downstream temperature sensor, and the temperature sensor are all electrically connected to the control circuit printed circuit board.

[0008] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: a flow sensor is used to monitor micro-leakage and flow rates exceeding normal operating conditions in pipelines; an independent temperature sensor is used to measure ambient temperature and simultaneously compensate for the temperature effect of pressure sensors and to precisely control the heating temperature of micro-heat sources. To avoid the instability of zero points caused by small temperature differences or external disturbances in the temperature field, which is common in thermal sensors, the heat source is typically set to a constant state. The transmission of pulses or heat waves is periodic; when the fluid is not flowing, the measured heat source conduction time is caused by thermal diffusion, which is a physical constant for a specific gas. Therefore, the measured values ​​are easy to interpret.

[0009] Furthermore, the thickness of the silicon nitride film ranges from 0.8 to 2 micrometers, and a passivation layer is provided on the micro heater, the upstream temperature sensor, and the downstream temperature sensor, with a thickness ranging from 0.5 to 1.2 micrometers; there is a gap between the micro heater, the upstream temperature sensor, and the downstream temperature sensor.

[0010] The beneficial effect of adopting the above-mentioned further technical solution is that, in order to ensure the reliability of the sensor, a passivation layer is set on the micro heater and the upstream and downstream temperature sensors.

[0011] Furthermore, the rectifier is located at the outlet end of the detection channel. The rectifier includes at least one inner cylinder and at least one outer cylinder. The outer cylinder is sleeved on the outside of the inner cylinder, and the detection channel is sleeved on the outside of the inner cylinder. The inner cylinder and the outer cylinder are coaxial. The microelectromechanical system (MEMS) flow sensor is located in the middle of the inner cylinder, and the surface of the MEMS flow sensor is perpendicular to the axis of the inner cylinder. A metal filter screen is provided on one side of the rectifier, and the mesh size of the metal filter screen is in the range of 80 to 300.

[0012] The beneficial effects of adopting the above-mentioned further technical solution are that, by inserting the sensor into the detection channel of the detection equipment, its sensing element is located at the center of the channel with the fastest gas flow rate, ensuring optimal sensitivity for minute gas flow rates. The sensor's direction is parallel to the gas flow direction, and its edge forms a boundary layer in the flow field, ensuring measurement stability. The center of the flow sensor on the sensor assembly is preferably placed at the center of the inner cylinder, with its surface perpendicular to the axis of the inner cylinder, to achieve optimal sensitivity for minute flow rate measurements. The metal filter screen serves to prevent particulate matter from entering the detection pipe and also has a certain rectifying effect to balance the requirements of rectification and pressure loss.

[0013] Furthermore, the rectifier is mounted on the detection channel via a nut and a sealing ring, and the sensor assembly is electrically connected to the control circuit printed circuit board via pin headers.

[0014] The beneficial effect of adopting the above-mentioned further technical solution is that the sensor assembly detection module is installed in the detection pipeline and fixed and isolated using seals and locking nuts. The preferred sealing method for the sensor assembly is the use of a sealing ring and nut compression, which can meet the sealing requirements of lower pressure civil gas pipelines. The electrical output of the sensor assembly is preferably connected to the control circuit printed circuit board of the detection equipment via a pin header.

[0015] Furthermore, the low-power motor valve is located at the outlet end of the detection channel. The low-power motor valve includes an active component and a passive component. The active component is mounted on the base, and the passive component is mounted in the detection channel. The active component and the passive component are connected in a transmission manner, and the active component is electrically connected to the control circuit printed circuit board.

[0016] The beneficial effect of adopting the above-mentioned further technical solution is that the motor drives the push rod to produce a circular motion, thereby causing the spring valve to move back and forth, achieving the function of blocking or opening. The micro-motor valve uses multiple sets of gears to drive a screw. Under the drive of the gears, the screw moves in a circular motion, thereby compressing or releasing a spring valve placed in the flow channel, achieving the purpose of opening or cutting off the gas supply in the pipeline. When the power supply to the city gas safety detection equipment is insufficient or interrupted, the valve automatically returns to its original position, closing the valve and cutting off the gas supply in the pipeline, ensuring the safety of downstream gas equipment. The linkage gear set drives the screw to rotate. The screw rotates in a circular motion in the flow channel. When the screw rotates towards the gas inlet end of the detection pipeline, the screw compresses the valve, gradually closing it; conversely, when the screw rotates towards the gas outlet end of the detection pipeline, the valve gradually opens.

[0017] Furthermore, the active component includes a linkage gear set and a screw, and the passive component includes a valve, a motor valve spring, and a main body. The linkage gear set is mounted on the base and is electrically connected to the control circuit printed circuit board. The screw is rotatably mounted on the linkage gear set. The screw, the valve, the motor valve spring, and the main body are all mounted in the detection flow channel. The valve is located on the rotation trajectory of the screw, the motor valve spring is connected to the valve, and the main body is located on the motion trajectory of the motor valve spring.

[0018] The beneficial effect of adopting the above-mentioned further technical solution is that the motor drives the push rod to produce a circular motion, thereby causing the spring valve to move back and forth, achieving the function of blocking or opening. The micro-motor valve uses multiple sets of gears to drive a screw. Under the drive of the gears, the screw moves in a circular motion, thereby compressing or releasing a spring valve placed in the flow channel, achieving the purpose of opening or cutting off the gas supply in the pipeline. When the power supply to the city gas safety detection equipment is insufficient or interrupted, the valve automatically returns to its original position, closing the valve and cutting off the gas supply in the pipeline, ensuring the safety of downstream gas equipment. The linkage gear set drives the screw to rotate. The screw rotates in a circular motion in the flow channel. When the screw rotates towards the gas inlet end of the detection pipeline, the screw compresses the valve, gradually closing it; conversely, when the screw rotates towards the gas outlet end of the detection pipeline, the valve gradually opens.

[0019] Furthermore, the control circuit printed circuit board includes: a microprocessor, sensor data acquisition and storage components, and a wireless data transmitter. The sensor components of the microelectromechanical system flow sensor and the pressure sensor are electrically connected to the sensor data acquisition and storage components. The sensor data acquisition and storage components and the wireless data transmitter are electrically connected to the microprocessor. The microprocessor is electrically connected to an alarm device, and the wireless data transmitter is wirelessly connected to a gas data control center and the user's mobile device.

[0020] The beneficial effects of adopting the above-mentioned further technical solution are as follows: A wireless data transmitter is used to send abnormal usage data to a designated gas data center and receive instructions from the data center. This data is also simultaneously transmitted to the gas user's mobile device; a microprocessor is used to process the measured flow and pressure signals. This facilitates the real-time transmission of abnormal states to the gas data control center and the user's mobile device via a wireless network. The microprocessor chip includes an analog-to-digital converter, processes analog signals from various sensors, and determines whether to trigger an alarm signal based on the upper and lower limits of various alarm parameters set by the user, executes valve opening and closing commands, and transmits the data to the designated data or control center via a wireless transmission chip. The microprocessor chip also includes a storage chip to record various abnormal signals collected. Furthermore, the microprocessor chip can receive signals from the data or control center and execute commands such as valve activation.

[0021] Furthermore, a top cover is installed on the base, a battery compartment is provided on the top cover, a power supply battery is provided in the battery compartment, a battery compartment cover is provided at the battery compartment, and the power supply battery is electrically connected to the control circuit printed circuit board; the top cover is provided with a gas flow mode indicator, a working status indicator, and a manual low-power active valve reset button, and the working status indicator and the manual low-power active valve reset button are both electrically connected to the control circuit printed circuit board.

[0022] The beneficial effects of adopting the above-mentioned further technical solutions are that the safety battery provides uninterrupted power to the device. Battery power supply meets the safety requirements of gas equipment. The manual low-power active valve reset button allows the valve to be manually opened on-site to restore normal gas supply when the valve is automatically shut off due to a detected fault, after the fault source or safety hazard has been manually eliminated, or when a network failure occurs. A manual valve reset function is also included. The manual valve opening function is a protection function that triggers valve closure due to a fault when the network connection is temporarily unavailable due to external reasons. After manual intervention to eliminate and repair the fault, the valve can be manually opened, allowing downstream gas equipment to operate normally. The top cover protects the control components; it also includes a battery compartment for easy battery replacement.

[0023] Furthermore, both ends of the detection channel are provided with movable connectors for connecting in series with the main gas pipeline.

[0024] The beneficial effects of adopting the above-mentioned further technical solution are that the microelectromechanical system (MEMS) thermal flow detection chip is placed in the main flow channel of the gas flow path in the urban gas safety detection equipment, instead of the bypass measurement design used in conventional flow measurement. The sensor chip is placed in a coaxial rectifier within the flow path, with its sensing position located at the center of the flow path. The chip surface is perpendicular to the gas flow direction, allowing a stable boundary layer to form as the gas flows parallel across the sensor surface, increasing measurement stability and repeatability. Another purpose of using direct measurement in the main flow path instead of shunting is to avoid the influence or blockage of the small bypass flow path by particulate matter or other impurities in the gas, which could cause the basic function of the equipment to fail. Simultaneously, the main flow measurement method eliminates the need for flow obstructions in the flow path, thus avoiding user interference. Furthermore, the main flow measurement method is unaffected by pressure changes in the gas flow path, resulting in more accurate measurements.

[0025] The advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of a microelectromechanical system flow sensor chip provided in an embodiment of the present invention.

[0028] Figure 2 This is a cross-sectional view of the detection device provided in an embodiment of the present invention.

[0029] Figure 3 This is a schematic diagram of the sensor assembly installation and detection position provided in an embodiment of the present invention.

[0030] Figure 4 This is a schematic diagram illustrating the installation and working principle of the active shut-off valve provided in an embodiment of the present invention.

[0031] Figure 5 An exploded view of the structural design of the detection equipment provided in an embodiment of the present invention.

[0032] Figure 6 This is an external view of the detection device provided in an embodiment of the present invention.

[0033] Reference numerals: 100, Microelectromechanical system (MEMS) flow sensor; 105, Silicon substrate; 110, Microheater; 120, Upstream temperature sensor; 130, Downstream temperature sensor; 140, Temperature sensor; 150, Insulation cavity; 210, Detection channel; 220, Substrate; 230, First mounting hole; 240, Second mounting hole; 300, Sensor assembly; 305, Position; 310, Rectifying component; 312, Inner cylinder; 314, Outer cylinder; 316, Metal filter screen; 322, Sensor assembly protective gasket; 324, Sealing gasket; 326, Nut; 328, Pin header; 400, Active component; 402. Linkage gear set; 405, screw; 410, passive component; 412, valve; 415, motor valve spring; 418, main body; 430, first screw group; 500, control circuit printed circuit board; 510, mounting stud; 522, second screw group; 600, top cover; 605, fixing screw hole; 610, battery compartment; 612, battery compartment cover; 614, manual screw group; 620, third screw group; 642, manual low-power active valve reset button; 645, working status indicator light; 648, gas flow mode indicator; 700, power supply battery; 800, detection equipment; 810, movable connector. Detailed Implementation

[0034] The principles and features of the present invention are described below with reference to the accompanying drawings. The embodiments described are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0035] like Figures 1 to 6 As shown, this embodiment of the invention provides a device for detecting the gas status of urban residential gas pipelines, comprising: a sensor assembly 300 equipped with a microelectromechanical system (MEMS) flow sensor 100 and a pressure sensor, a detection flow channel 210, a substrate 220, a rectifier 310, a low-power motor valve, and a control circuit printed circuit board 500. The rectifier 310 and the low-power motor valve are both installed in the detection flow channel 210, the sensor assembly 300 is installed on the rectifier 310, the substrate 220 is installed on the detection flow channel 210, and the control circuit printed circuit board 500 is installed on the substrate 220. The sensor assembly 300 and the low-power motor valve are both electrically connected to the control circuit printed circuit board 500.

[0036] The beneficial effects of adopting the technical solution of this invention are as follows: a flow sensor is used to monitor micro-leakage and flow rates exceeding normal operating conditions in the pipeline; a pressure sensor is used to monitor the pressure status of the pipeline; a temperature sensor is used to measure the safe operating temperature of gas and compensate for the temperature effect of the pressure sensor; and a low-power motor valve is used to actively shut off the upstream gas supply when an abnormal gas condition is detected in the pipeline. By detecting micro-leakage flow, pressure status, and overflow in household gas pipelines, safety accidents during gas use can be avoided. It can measure micro-leakage below the safe leakage level, quickly measure overflow and the safe pressure range of the pipeline, and is equipped with an active safety valve that actively cuts off the gas source when the set safe operating parameters are abnormal, and transmits the abnormal status in real time to the gas data control center and the user's mobile device via a wireless network. This device is suitable for all types of civil gas pipelines and is battery powered, meeting the safety level required for gas equipment. The microelectromechanical heating flow sensor is placed inside the gas pipeline; its small size does not increase pressure loss.

[0037] like Figures 1 to 6 As shown, the microelectromechanical system flow sensor 100 further includes: a silicon substrate 105, a micro heater 110, an upstream temperature sensor 120, a downstream temperature sensor 130, and a temperature sensor 140. The micro heater 110, the upstream temperature sensor 120, the downstream temperature sensor 130, and the temperature sensor 140 are all mounted on the silicon substrate 105. The micro heater 110 is located between the upstream temperature sensor 120 and the downstream temperature sensor 130. A heat insulation cavity 150 is provided on the silicon substrate 105, and a silicon nitride thin film is provided in the heat insulation cavity 150. The micro heater 110, the upstream temperature sensor 120, and the downstream temperature sensor 130 are all located above the silicon nitride thin film. The micro heater 110, the upstream temperature sensor 120, the downstream temperature sensor 130, and the temperature sensor 140 are all electrically connected to the control circuit printed circuit board 500.

[0038] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: a flow sensor is used to monitor micro-leakage and flow rates exceeding normal operating conditions in pipelines; an independent temperature sensor is used to measure ambient temperature and simultaneously compensate for the temperature effect of pressure sensors and to precisely control the heating temperature of micro-heat sources. To avoid the instability of zero points caused by small temperature differences or external disturbances in the temperature field, which is common in thermal sensors, the heat source is typically set to a constant state. The transmission of pulses or heat waves is periodic; when the fluid is not flowing, the measured heat source conduction time is caused by thermal diffusion, which is a physical constant for a specific gas. Therefore, the measured values ​​are easy to interpret.

[0039] like Figures 1 to 6 As shown, the thickness of the silicon nitride film ranges from 0.8 to 2 micrometers, and a passivation layer is provided on the micro heater 110, the upstream temperature sensor 120, and the downstream temperature sensor 130, with a thickness ranging from 0.5 to 1.2 micrometers; there is a gap between the micro heater 110, the upstream temperature sensor 120, and the downstream temperature sensor 130.

[0040] The beneficial effect of adopting the above-mentioned further technical solution is that, in order to ensure the reliability of the sensor, a passivation layer is set on the micro heater and the upstream and downstream temperature sensors.

[0041] like Figures 1 to 6 As shown, further, the rectifier 310 is located at the outlet end of the detection channel 210. The rectifier 310 includes at least one inner cylinder 312 and at least one outer cylinder 314. The outer cylinder 314 is sleeved on the outside of the inner cylinder 312, and the detection channel 210 is sleeved on the outside of the inner cylinder 312. The inner cylinder 312 and the outer cylinder 314 are coaxial. The microelectromechanical system flow sensor 100 is located in the middle of the inner cylinder 312, and the surface of the microelectromechanical system flow sensor 100 is perpendicular to the axis of the inner cylinder 312. A metal filter screen 316 is provided on one side of the rectifier 310, and the mesh size of the metal filter screen 316 is in the range of 80~300.

[0042] The beneficial effects of adopting the above-mentioned further technical solution are that, by inserting the sensor into the detection channel of the detection equipment, its sensing element is located at the center of the channel with the fastest gas flow rate, ensuring optimal sensitivity for minute gas flow rates. The sensor's direction is parallel to the gas flow direction, and its edge forms a boundary layer in the flow field, ensuring measurement stability. The center of the flow sensor on the sensor assembly is preferably placed at the center of the inner cylinder, with its surface perpendicular to the axis of the inner cylinder, to achieve optimal sensitivity for minute flow rate measurements. The metal filter screen serves to prevent particulate matter from entering the detection pipe and also has a certain rectifying effect to balance the requirements of rectification and pressure loss.

[0043] like Figures 1 to 6 As shown, the rectifier 310 is further mounted on the detection channel 210 via a nut 326 and a sealing ring, and the sensor assembly 300 is electrically connected to the control circuit printed circuit board 500 via a pin header 328.

[0044] The beneficial effect of adopting the above-mentioned further technical solution is that the sensor assembly detection module is installed in the detection pipeline and fixed and isolated using seals and locking nuts. The preferred sealing method for the sensor assembly is the use of a sealing ring and nut compression, which can meet the sealing requirements of lower pressure civil gas pipelines. The electrical output of the sensor assembly is preferably connected to the control circuit printed circuit board of the detection equipment via a pin header.

[0045] like Figures 1 to 6 As shown, the low-power motor valve is located at the outlet end of the detection channel 210. The low-power motor valve includes an active component 400 and a passive component 410. The active component 400 is mounted on the base 220, and the passive component 410 is mounted in the detection channel 210. The active component 400 and the passive component 410 are connected by a transmission connection. The active component 400 is electrically connected to the control circuit printed circuit board 500.

[0046] The beneficial effect of adopting the above-mentioned further technical solution is that the motor drives the push rod to produce a circular motion, thereby causing the spring valve to move back and forth, achieving the function of blocking or opening. The micro-motor valve uses multiple sets of gears to drive a screw. Under the drive of the gears, the screw moves in a circular motion, thereby compressing or releasing a spring valve placed in the flow channel, achieving the purpose of opening or cutting off the gas supply in the pipeline. When the power supply to the city gas safety detection equipment is insufficient or interrupted, the valve automatically returns to its original position, closing the valve and cutting off the gas supply in the pipeline, ensuring the safety of downstream gas equipment. The linkage gear set drives the screw to rotate. The screw rotates in a circular motion in the flow channel. When the screw rotates towards the gas inlet end of the detection pipeline, the screw compresses the valve, gradually closing it; conversely, when the screw rotates towards the gas outlet end of the detection pipeline, the valve gradually opens.

[0047] like Figures 1 to 6 As shown, the active component 400 further includes a linkage gear set 402 and a screw 405. The passive component 410 includes a valve 412, a motor valve spring 415, and a main body 418. The linkage gear set 402 is mounted on the base 220 and is electrically connected to the control circuit printed circuit board 500. The screw 405 is rotatably mounted on the linkage gear set 402. The screw 405, the valve 412, the motor valve spring 415, and the main body 418 are all mounted in the detection flow channel 210. The valve 412 is located on the rotation trajectory of the screw 405. The motor valve spring 415 is connected to the valve 412. The main body 418 is located on the movement trajectory of the motor valve spring 415.

[0048] The beneficial effect of adopting the above-mentioned further technical solution is that the motor drives the push rod to produce a circular motion, thereby causing the spring valve to move back and forth, achieving the function of blocking or opening. The micro-motor valve uses multiple sets of gears to drive a screw. Under the drive of the gears, the screw moves in a circular motion, thereby compressing or releasing a spring valve placed in the flow channel, achieving the purpose of opening or cutting off the gas supply in the pipeline. When the power supply to the city gas safety detection equipment is insufficient or interrupted, the valve automatically returns to its original position, closing the valve and cutting off the gas supply in the pipeline, ensuring the safety of downstream gas equipment. The linkage gear set drives the screw to rotate. The screw rotates in a circular motion in the flow channel. When the screw rotates towards the gas inlet end of the detection pipeline, the screw compresses the valve, gradually closing it; conversely, when the screw rotates towards the gas outlet end of the detection pipeline, the valve gradually opens.

[0049] like Figures 1 to 6 As shown, the control circuit printed circuit board 500 further includes: a microprocessor, sensor data acquisition and storage components, and a wireless data transmitter. The microelectromechanical system flow sensor 100 and the sensor assembly 300 of the pressure sensor are both electrically connected to the sensor data acquisition and storage components. The sensor data acquisition and storage components and the wireless data transmitter are both electrically connected to the microprocessor. The microprocessor is electrically connected to an alarm device, and the wireless data transmitter is wirelessly connected to a gas data control center and the user's mobile device.

[0050] The beneficial effects of adopting the above-mentioned further technical solution are as follows: A wireless data transmitter is used to send abnormal usage data to a designated gas data center and receive instructions from the data center. This data is also simultaneously transmitted to the gas user's mobile device; a microprocessor is used to process the measured flow and pressure signals. This facilitates the real-time transmission of abnormal states to the gas data control center and the user's mobile device via a wireless network. The microprocessor chip includes an analog-to-digital converter, processes analog signals from various sensors, and determines whether to trigger an alarm signal based on the upper and lower limits of various alarm parameters set by the user, executes valve opening and closing commands, and transmits the data to the designated data or control center via a wireless transmission chip. The microprocessor chip also includes a storage chip to record various abnormal signals collected. Furthermore, the microprocessor chip can receive signals from the data or control center and execute commands such as valve activation.

[0051] like Figures 1 to 6As shown, further, a top cover 600 is mounted on the base 220, a battery compartment 610 is provided on the top cover 600, a power supply battery 700 is provided in the battery compartment 610, a battery compartment cover 612 is provided at the battery compartment 610, and the power supply battery 700 is electrically connected to the control circuit printed circuit board 500; the top cover 600 is provided with a gas flow mode indicator 648, a working status indicator 645, and a manual low-power active valve reset button 642, and the working status indicator 645 and the manual low-power active valve reset button 642 are both electrically connected to the control circuit printed circuit board 500.

[0052] The beneficial effects of adopting the above-mentioned further technical solutions are that the safety battery provides uninterrupted power to the device. Battery power supply meets the safety requirements of gas equipment. The manual low-power active valve reset button allows the valve to be manually opened on-site to restore normal gas supply when the valve is automatically shut off due to a detected fault, after the fault source or safety hazard has been manually eliminated, or when a network failure occurs. A manual valve reset function is also included. The manual valve opening function is a protection function that triggers valve closure due to a fault when the network connection is temporarily unavailable due to external reasons. After manual intervention to eliminate and repair the fault, the valve can be manually opened, allowing downstream gas equipment to operate normally. The top cover protects the control components; it also includes a battery compartment for easy battery replacement.

[0053] like Figures 1 to 6 As shown, both ends of the detection channel 210 are provided with movable connectors 810 for connecting in series with the main gas pipeline.

[0054] The beneficial effects of adopting the above-mentioned further technical solution are that the microelectromechanical system (MEMS) thermal flow detection chip is placed in the main flow channel of the gas flow path in the urban gas safety detection equipment, instead of the bypass measurement design used in conventional flow measurement. The sensor chip is placed in a coaxial rectifier within the flow path, with its sensing position located at the center of the flow path. The chip surface is perpendicular to the gas flow direction, allowing a stable boundary layer to form as the gas flows parallel across the sensor surface, increasing measurement stability and repeatability. Another purpose of using direct measurement in the main flow path instead of shunting is to avoid the influence or blockage of the small bypass flow path by particulate matter or other impurities in the gas, which could cause the basic function of the equipment to fail. Simultaneously, the main flow measurement method eliminates the need for flow obstructions in the flow path, thus avoiding user interference. Furthermore, the main flow measurement method is unaffected by pressure changes in the gas flow path, resulting in more accurate measurements.

[0055] This invention relates to the detection of urban residential gas pipelines; particularly, it relates to the real-time comprehensive detection of gas usage using low-power microprocessor-based current, pressure, and temperature sensing chips to ensure the normal and safe use of gas. This invention discloses a design for an urban gas detection device utilizing a microelectromechanical system (MEMS) flow sensor 100 and a pressure sensor. This detection device prevents gas-related safety accidents by detecting minute leaks, pressure conditions, and overflows in household gas pipelines. This device can measure minute leaks below the safe leakage threshold, quickly measure overflows and the safe pressure range of the pipeline, and is equipped with an active safety valve. When the set safety parameters are abnormal, it actively cuts off the gas source in the pipeline and transmits the abnormal status in real time via a wireless network to the gas data control center and the user's mobile device. This device is suitable for all types of residential gas pipelines and is battery-powered, meeting the safety requirements of gas equipment.

[0056] This invention provides a device for detecting the gas status of urban residential gas pipelines, comprising: a flow sensor for monitoring micro-leakage and flow rates exceeding normal usage levels in the pipeline; a pressure sensor for monitoring pipeline pressure; a temperature sensor 140 for measuring the safe operating temperature of the gas and compensating for the temperature effect of the pressure sensor; a low-power motor valve for actively shutting off the upstream gas supply to the user when an abnormal gas status is detected; a wireless data transmitter for sending abnormal usage data to a designated gas data center and receiving instructions from the data center. This data is also simultaneously transmitted to the gas user's mobile device; a microprocessor for processing the measured flow and pressure signals to achieve the above functions; and a safety battery for providing uninterrupted power to the device.

[0057] The device used to detect the gas status of urban residential gas pipelines includes a flow sensor manufactured using microelectromechanical systems (MEMS) technology. The MEMS flow sensor 100 employs the thermal time-of-flight measurement principle, featuring a micro-heat source and three temperature sensors. It has a dynamic measurement range of no less than 1000:1, with a minimum measured flow velocity not exceeding 0.01 m / sec. The average power consumption of its micro-heat source does not exceed 200 microamps. The temperature sensors are composed of thermopile structures and require no external power supply. The MEMS flow sensor 100 also includes a heat-insulating cavity 150 and a dynamic response of no more than 2 milliseconds.

[0058] The preferred method for measuring the thermal time-of-flight or direct gas flow thermal conduction of a flow sensor in a microelectromechanical system (MEMS) is to load a thermal pulse onto a micro heat source and measure the time in the time domain by which the gas flow carries the thermal pulse at a specific distance (i.e., the distance between the micro heat source and the upstream and downstream temperature sensors) to directly measure the gas flow rate.

[0059] The sensor is preferably a sensing chip fabricated on a silicon substrate, which has an independent temperature sensor for measuring ambient temperature and simultaneously compensating for the temperature effect of the pressure sensor and for precisely controlling the heating temperature of the micro heat source.

[0060] The microelectromechanical system (MEMS) flow sensor 100 is preferably placed in the detection channel 210 of the corresponding detection device using an insertion method. Its sensing element is located at the center of the channel with the fastest gas flow rate, ensuring optimal sensitivity for even small gas flow rates. The sensor is oriented parallel to the gas flow direction, and its edge forms a boundary layer in the flow field, ensuring measurement stability.

[0061] Installation method: The sensor is preferably placed in a concentric ring-shaped rectifier (rectifier component 310) by insertion. The rectifier consists of no fewer than two concentric cylinders, whose axis coincides with the axis of the flow channel.

[0062] The device used to detect the gas status of urban residential gas pipelines includes a pressure sensor manufactured using microelectromechanical systems (MEMS) technology. Its measurement principle utilizes the physical process of pressure-induced resistance change. Its structure involves depositing a non-metallic thin film, such as silicon nitride, on a silicon wafer, followed by the deposition of a piezoelectric material, with a cavity created beneath the film. Pressure causes deformation of the film, which in turn causes corresponding deformation of the piezoelectric material, with the change in resistance corresponding to the pressure change. The microelectromechanical pressure sensor can measure pressures up to 6 kPa and has a withstand pressure of at least 3 times its rated pressure and a maximum pressure of at least 5 times its rated pressure.

[0063] The pressure sensor is preferably placed on the inner wall of the gas pipeline to avoid increasing pressure loss in the gas pipeline. The pressure sensor features corrosion protection and gas compatibility.

[0064] The device used to detect the gas status of urban residential gas pipelines features a low-power motor valve. This low-power motor valve consists of multiple sets of gears (linkage gear set 402), a push rod (screw 405), and a spring valve (passive component 410) placed in the flow channel. The motor drives the push rod to produce a circular motion, which in turn causes the spring valve to move back and forth, achieving the function of blocking or opening.

[0065] The device used to detect the gas status of urban residential gas pipelines has a wireless data transmission chip (wireless data transmitter). This wireless data transmission chip can adopt various forms such as Bluetooth Low Energy, NB-IoT, 3G / 4G / 5G, LoRaWAN or WIFI, depending on the actual field requirements.

[0066] The device used to detect the gas status of urban residential gas pipelines has a microprocessor chip. This microprocessor chip includes an analog-to-digital converter, processes analog signals from various sensors, and determines whether to trigger an alarm signal based on user-set alarm limits, executes valve opening / closing commands, and transmits the data to a designated data or control center via a wireless transmission chip. The microprocessor chip also includes a storage chip to record various abnormal signals collected. Furthermore, the microprocessor chip can receive signals from the data or control center and execute commands such as valve activation.

[0067] The equipment used to detect the gas status of urban residential gas pipelines operates in a low-power state, is powered by lithium batteries, and can work continuously for no less than one year, preferably three years.

[0068] The device for detecting the gas status of urban residential gas pipelines has a status display, preferably an LED light; the status is not limited to the working status of the detection device, the wireless network status, and the battery level. The device has a manual valve reset device (manual low-power active valve reset button 642), which allows the valve to be manually opened on-site to restore normal gas use after the valve is automatically shut off due to a detected fault, the fault source or safety hazard has been manually eliminated, or when a network failure occurs.

[0069] Using thermal flow sensors to measure leaks is a standard method in industrial leak detection equipment, with over 80 years of application. Microelectromechanical (MEMS) thermal flow sensors, compared to traditional thermal flow sensors, further increase measurement sensitivity while significantly reducing power consumption, cost, and size, making their application in leak detection for urban gas pipelines possible. Placed inside the gas pipeline, the MEMS thermal flow sensor is small in size and does not increase pressure loss, making it the ideal choice for this application.

[0070] One objective of this invention is to leverage the capabilities and advantages of microelectromechanical systems (MEMS) gas mass flow sensor chips for measuring minute flow rates or leaks in small-diameter urban gas pipelines. This invention aims to design and manufacture a detection device for safe urban gas usage, featuring a low-power valve that actively cuts off upstream gas supply upon detecting fault conditions, thus enhancing the safety of urban gas usage. The MEMS gas mass flow sensor chip directly detects the heat conduction generated by gas flow over time, sensing the dynamic range of gas usage and potential micro-leakage. Compared to existing calorimetric MEMS gas flow sensors that measure temperature changes in the gas flow path, the design and manufacturing method of this invention improves the dynamic measurement and detection capabilities of MEMS thermal sensing chips by nearly 50%. Detailed design of the MEMS flow sensor can be developed within [the specified timeframe]. Figure 1The sensor of this invention has a thermistor temperature sensor (including a microheater), which is fabricated on a thermally insulating membrane of a diaphragm structure. The thermally insulating membrane of the diaphragm structure is completed through an opening slit in the membrane. The microheater 110 is preferably made of a noble metal such as platinum or heavily doped polycrystalline silicon, and the upstream and downstream thermistors are preferably made of thermal push sensors. In actual measurement, a pulse signal is applied to the microheat source, and the upstream and downstream thermal push sensors measure the arrival time of the pulse in the time domain. Since the fabrication process of the microelectromechanical system flow sensor 100 is similar to that of semiconductors, multiple illumination methods are used to fabricate each functional element. Therefore, the interval between the thermal push and the heat source can reach nanometer precision, and the electronic circuit can realize accurate measurement of the heat pulse conduction time, thereby enabling the measurement of minute flow rates unaffected by the environment. Furthermore, traditional temperature measurement is easily affected by ambient temperature, and the measurement of minute flow rates often has larger errors. However, in the time domain measurement method of this invention, the flow rate of minute flow rates is slower, so the heat pulse takes longer to reach the upstream and downstream at a fixed distance, and the time measurement error is smaller. Therefore, compared with the traditional method, the measurement of minute flow rates is more accurate. This also avoids zero-point instability caused by temperature measurement. This measurement method is more suitable for the design requirements of the measuring device of this invention.

[0071] Another objective of this invention is to design and manufacture a detection device for safe use of urban gas, leveraging the capabilities and advantages of microelectromechanical systems (MEMS) gas mass flow sensor chips for measuring minute flow rates or leaks in small-diameter urban gas pipelines. This device possesses industrial-grade micro-leakage measurement capabilities, with a dynamic range of at least 1000:1 and a minimum detectable flow velocity not exceeding 0.01 m / sec. Utilizing the orifice plate measurement principle, the measured micro-flow rate can estimate the orifice size of the leak point. Combined with the micro-flow rate measurement, the severity of the leak can be determined, and the fault data can be promptly transmitted to a designated data center via the device's wireless transmission function. Furthermore, the leakage rate of this device can be set according to the user's actual usage conditions via the device's data interface or a remote central terminal. When the detected leakage rate reaches this threshold, the alarm function is activated.

[0072] Another objective of this invention is to place the microelectromechanical system (MEMS) thermal flow detection chip in the main flow channel of a gas flow path in a city gas safety detection device, instead of using a bypass measurement design as in conventional flow measurement. The sensor chip is placed in a coaxial rectifier (rectifier component 310) within the flow path, with its sensing position located at the center of the flow path. The chip surface is perpendicular to the gas flow direction, allowing a stable boundary layer to form as the gas flows parallel across the sensor surface, increasing measurement stability and repeatability. Another objective of using direct measurement in the main flow path instead of a branch flow is to avoid the influence or blockage of the small bypass flow path by particulate matter or other impurities in the gas, which could cause the device's basic functions to fail. Simultaneously, the main flow measurement method eliminates the need for flow obstructions (pressure loss) in the flow path, thus avoiding user disruption. Furthermore, the main flow measurement method is unaffected by pressure changes in the gas flow path, resulting in more accurate measurements.

[0073] Another objective of this invention is to provide a detection and protection function for overcurrent devices in urban gas usage safety. Based on the user's actual usage, the device calculates and judges overcurrent or excessive flow alarms and protection functions for piped gas using real-time data measured by a microelectromechanical system (MEMS) flow chip and pressure chip. The pressure sensor chip employs mature piezoelectric sensing technology. This pressure sensor measures the absolute pressure in the gas flow channel and is placed on the pipe wall of the gas flow channel in the urban gas usage safety detection device, without generating any additional pressure loss in the pipeline. When the flow rate and pressure values ​​measured by the device reach the overcurrent alarm value set according to the user's usage, the device will immediately activate the overcurrent protection function. The device's active valve will cut off the upstream gas supply, keeping the downstream gas equipment in a safe state. Simultaneously, the device sends the measured data and alarm signal to a designated data control center.

[0074] Another objective of this invention is to incorporate a low-power micro-motor valve into a city gas safety detection device. This valve, controlled by the device's control circuitry, can proactively cut off the upstream gas supply as needed, ensuring the safety of downstream gas equipment. The micro-motor valve utilizes multiple sets of gears to drive a screw. Under the drive of the gears, the screw moves in a circular motion, compressing or releasing a spring valve located in the flow channel, thus opening or cutting off the gas supply in the pipeline. When the city gas safety detection device experiences insufficient power or a power outage, the valve automatically returns to its original position, closing and cutting off the gas supply in the pipeline, ensuring the safety of downstream gas equipment.

[0075] Another objective of this invention is to incorporate a low-power wireless data transmission module into a detection device for safe urban gas usage. This module, controlled by the device's control circuitry, transmits data about various abnormal or normal states detected by the device in the gas pipeline. Depending on the actual user's environment, the wireless transmission module can utilize technologies such as Bluetooth Low Energy, Wi-Fi, NB-IoT, LoRaWAN, 3G / 4G / 5G, and CAT-M.

[0076] Another objective of this invention is to incorporate multiple device operating status displays into a safety monitoring device for urban gas usage. These displays may include, but are not limited to, battery level, alarm status, and valve status. The device operating status can be displayed using different colors of low-power LEDs. These statuses help users intuitively understand the device's operational condition. For example, the battery level status can remind customers to replace the batteries in a timely manner. If no alarm is triggered, the device will also send these operating statuses to a designated data control center daily.

[0077] Another objective of this invention is to provide a manual reset (open) valve function in a detection device for safe use of urban gas. The manual valve opening function is a protection function that triggers valve closure due to a fault when the network connection is temporarily unavailable due to external reasons. After manual intervention to eliminate and repair the fault, the valve can be manually opened, allowing downstream gas equipment to operate normally.

[0078] Another objective of this invention is to provide a protective device for urban gas safety testing equipment that uses flame-retardant materials that meet gas safety requirements, and whose electrical performance meets the protection level for safe gas use.

[0079] The second objective of this invention is that the microelectromechanical system (MEMS) flow chip used in the urban gas safety detection equipment possesses metering accuracy. Besides detecting micro-leakage and overflow conditions in the pipeline, it measures the gas mass flow rate under normal operating conditions. Using the pipeline pressure and temperature data simultaneously collected by the equipment, the volumetric flow rate for normal gas use can be calculated. This volumetric flow rate can be compared with the data from gas meters currently used for gas metering and billing, further enhancing the management of gas metering and billing, avoiding trade discrepancies and disputes arising from gas meter malfunctions, and improving the overall level of gas management.

[0080] The manufacturing method provided by this invention is used to manufacture the above-mentioned testing equipment for safe use of urban gas, and includes the following steps: The equipment's detection tube and the mounting base for intelligent components are made from a single, integrally molded metal. Anodized aluminum alloy is the preferred material, but copper or stainless steel, which are permissible for gas safety, can also be used.

[0081] The mounting base for intelligent components is equipped with mounting holes for sensor components and active low-power motor valves, which are connected to the detection tube.

[0082] The two ends of the test pipe are connected by threads and unions to meet the installation specifications for civil gas pipeline components.

[0083] For mounting base parts with strict installation size requirements, further precision machining processes such as turning and milling are used.

[0084] The microelectromechanical system flow chip (with an integrated temperature sensor) and the microelectromechanical voltage and pressure chip are integrated on the detection probe assembly (sensor assembly).

[0085] The control circuit of the detection equipment includes a printed circuit board containing intelligent control elements, which includes a microprocessor for acquiring and analyzing signals from various sensors and determining whether to trigger an alarm signal based on the signals.

[0086] The control circuit of the testing equipment also includes a wireless signal transmission and reception module for exchanging information with a designated data control center.

[0087] The testing equipment also includes a top cover for protecting the control components; the top cover also has a battery compartment for easy battery replacement.

[0088] Furthermore, the procedure also includes the step of installing the sensor assembly detection module in the detection pipeline and securing and isolating it using seals and locking nuts.

[0089] Furthermore, the process also includes the step of mounting the active low-power motor valve on the smart component mounting base and securing it with a sealing ring and screws.

[0090] Furthermore, it also includes the step of fixing the printed circuit board of the intelligent control element to the intelligent component mounting base with screws.

[0091] Furthermore, it also includes the step of connecting the sensor component detection module and the active low-power motor valve to the printed circuit board of the intelligent control element.

[0092] Furthermore, the procedure includes the step of securing the top cover of the testing device to the mounting base of the smart components using a sealing ring and screws. The battery will be placed after the device is installed on the gas pipeline to be tested.

[0093] The beneficial effects of this invention are: it provides a gas detection device that includes an industrial-grade micro-leakage detection microelectromechanical system (MEMS) flow sensing chip and pressure and temperature sensors; and it is equipped with an active low-power motor valve. Therefore, this detection device can perform comprehensive detection and protection for the safety of residential gas. Simultaneously, the collected mass flow rate and volumetric flow rate data can be further compared with the pure volumetric flow rate data of current mechanical metering instruments, further improving the level of gas usage management. The urban gas safety detection device obtained using the above manufacturing method is simple and easy to manufacture. Compared with traditional leakage and other safety parameter detection devices, the cost is significantly reduced, and the installation is simple, providing an achievable method and tool for improving the safety and management level of residential gas.

[0094] Example The preferred design structure of the microelectromechanical system flow sensor 100 used in this invention is as follows: Figure 1 As shown. The sensor includes a silicon substrate 105, a microheater 110, an upstream temperature sensor 120 and a downstream temperature sensor 130 for measuring heat conduction caused by (micro)flow; a temperature sensor 140 for measuring the gas temperature in the pipeline; and a heat insulation cavity 150 disposed below the microheater 110 and the upstream and downstream temperature sensors. Above the heat insulation cavity 150 is a 0.8-2 micrometer silicon nitride film, preferably 1.2 micrometers thick, to support the microheater 110 and the upstream and downstream temperature sensors. The silicon nitride film can also be replaced by a mixture (multilayer) of materials such as silicon nitride, silicon oxide, and silicon carbide. To ensure the reliability of the sensor, a passivation layer is provided on the microheater 110 and the upstream and downstream temperature sensors, which is a silicon nitride film with a thickness of 0.5-1.2 micrometers, preferably 0.8 micrometers, made of silicon nitride or silicon carbide.

[0095] Specifically, such as Figure 1As shown, the leakage and gas flow rate are measured by the microelectromechanical system (MEMS) flow sensor 100, employing a measurement method unique to this invention to ensure accuracy, reliability, and long-term stability. In this embodiment, a thermal pulse is applied to the microheater 110 of the sensor, and the time it takes for the pulse to conduct from the microheat source to the temperature sensor is measured from the temperature resistors of the upstream temperature sensor 120 and the downstream temperature sensor 130, respectively. Furthermore, a periodic thermal wave can also be applied to the microheater 110, and the modulated signal can be measured at the upstream and downstream temperature sensors 120 and 130, respectively. This method differs from the current thermal sensor technology that measures temperature differences. Its advantage lies in the accurate measurement of small flow rates or microleakage. Since the distance L between the microheat source (microheater 110) and the upstream and downstream temperature sensors (upstream temperature sensor 120 and downstream temperature sensor 130) on the sensing chip (MEMS flow sensor 100) is determined by the illumination of the semiconductor process, it has high precision. Therefore, accurate flow rate measurement depends solely on the time t taken for the thermal pulse or heat wave to conduct, which can be obtained by multiplying the fluid velocity, v (v = L / t), by the fixed area of ​​the flow channel. The slower the flow velocity, the longer the required time, thus ensuring higher measurement accuracy. This method disclosed in this invention also helps avoid the instability of the zero point commonly found in thermal sensors due to small temperature differences or external disturbances in the temperature field, as the heat source is typically set to a constant state. The transmission of the pulse or heat wave is periodic; when the fluid is not flowing, the measured heat source conduction time is due to thermal diffusion, which is a physical constant for a specific gas. Therefore, the obtained measurement values ​​are easily interpreted.

[0096] In this invention, gas temperature measurement is preferably achieved using a temperature sensor 140 integrated into the microelectromechanical system (MEMS) flow sensor 100. This temperature sensor 140, after being calibrated using conventional semiconductor temperature sensor calibration methods, achieves the required measurement accuracy. Gas pressure measurement is preferably performed using a commercially available MEMS pressure sensor adapted to gas environments, preferably based on the piezoelectric principle. (Refer to...) Figure 2 The microelectromechanical system (MEMS) flow sensor 100 and pressure sensor are integrated on the same module, forming the core module component for detection and measurement (sensor component 300). It measures the flow rate, pressure, and temperature of the gas in real time.

[0097] In embodiments of the present invention, such as Figure 2 and Figure 3As shown, the sensor assembly 300 is preferably placed in the rectifier 310 of the detection channel 210. The rectifier 310 is preferably a set of concentric cylinders, the axis of which is parallel to the detection channel 210. The number of concentric cylinders is determined by the size of the detection pipe diameter. For the pipe size of civil gas equipment, the number of cylinders is preferably two: an inner cylinder 312 and an outer cylinder 314. The sensor assembly 300 and the rectifier 310 are preferably placed at the gas outlet end of the detection equipment. The center of the flow sensor (microelectromechanical system flow sensor 100) on the sensor assembly 300 is preferably placed at the center of the inner cylinder 312, and its surface is perpendicular to the axis of the inner cylinder 312 to achieve the best sensitivity for micro-flow measurement. Further, a metal filter 316 is preferably placed at the gas inlet end of the inner cylinder 312 of the rectifier 310. Its function is to prevent particulate matter from entering the detection pipe and at the same time to have a certain rectification effect. The mesh size of the filter can be selected from 80 to 300, preferably 150, to balance the requirements of rectification and pressure loss. The sensor assembly 300 is preferably sealed by a sealing ring and nut 326, which can meet the sealing requirements of lower pressure in residential gas pipelines. The electrical output of the sensor assembly 300 is preferably connected to the control circuit printed circuit board 500 of the detection equipment via a pin header 328.

[0098] In embodiments of the present invention, a low-power active motor valve is preferably provided. (Refer to...) Figure 2 and Figure 4 The motor valve consists of two parts: an active component 400 and a passive component 410. The active component 400's active opening and closing function is achieved by using a multi-set of linked gears (linkage gear set 402) driven by current to push a rotating screw 405 to compress and release the valve. The screw 405 is positioned at the center of the detection channel, and its length within the channel is less than the channel diameter, typically 5 / 8 to 7 / 8 of the channel diameter; preferably 3 / 4. The passive mechanism 410 consists of a valve 412, a motor valve spring 415, and a fixed body 418. The body 418 is threaded into the detection pipe. The working principle of the active motor valve is that the linkage gear set 402 drives the screw 405 to rotate. The screw 405 rotates in a circular motion within the flow channel. When the screw 405 rotates towards the air inlet of the detection pipe, it compresses the valve 412, gradually closing it. Conversely, when the screw 405 rotates towards the air outlet of the detection pipe, the valve 412 gradually opens. Figure 2 As shown, the motor valve is preferably located at the air inlet end of the testing equipment. The electrical connection of the active mechanism (active component 400) is preferably made by means of a flexible cable with a plug to connect to the control circuit printed circuit board 500 of the testing equipment.

[0099] This invention also provides a manufacturing method, referring to... Figure 5The device 800, used for manufacturing a testing device for safe use of urban gas, includes the following main components: a testing pipe (testing channel 210) and a base 220; a microelectromechanical system (MEMS) flow sensor 100, a pressure sensor and a temperature sensor assembly; a low-power active motor valve active component (active component 400) and a passive component 410; a control circuit (control circuit printed circuit board 500); a top cover 600 with a battery compartment 610; a power supply battery 700 and a movable connector 810.

[0100] Specifically, refer to Figure 5 The detection pipe (detection flow channel 210) and the base 220 of the detection equipment are preferably manufactured by metal die casting. They are provided with a first mounting hole 230 for mounting a microelectromechanical system sensor assembly (sensor assembly 300), a second mounting hole 240 for mounting an active low-power motor valve (active component 400 and passive component 410), control circuit fixing screw holes (mounting studs 510), and four fixing screw holes 605 symmetrically arranged on the edge of the base 220 for mounting the top cover 600.

[0101] Reference Figure 5 First, place the rectifier component 310 at the outlet end of the detection channel 210 of the detection equipment, and confirm that the insertion position 305 of the sensor assembly 300 on it is aligned with the center of the sensor assembly mounting hole (first mounting hole 230) to ensure that there is no misalignment or inability to install the sensor assembly 300. Then, insert the sensor assembly 300 into the first mounting hole 230 on the base 220. After confirming that the position of the installed sensor assembly 300 is correct, place the sensor assembly protective gasket 322 and sealing gasket 324 on top of the sensor assembly 300, and then use the sealing nut (nut 326) to fix and seal the sensor assembly 300 to the first mounting hole 230 of the detection equipment base 220.

[0102] Continue to refer to Figure 5 Place the passive mechanism (passive component 410) of the micro-power motor valve at the outlet end of the detection pipe (detection channel 210) of the detection equipment. Ensure that the position of its valve orifice aligns with the position of the screw 405 of the active mechanism (active component 400) of the micro-power motor valve on the base 220 of the detection equipment. Then, install the movable connector (movable connector 810) at the outlet end of the detection equipment onto the base 220 of the detection equipment, while simultaneously fixing the passive component 410 of the micro-power motor valve. After confirming that the above steps are correct, install the active component 400 of the micro-power motor valve onto the base 220 of the detection equipment using the first set of screws 430.

[0103] Still refer to Figure 5The control circuit board (control circuit printed circuit board 500) of the detection equipment consists of two circuit boards. The lower circuit board houses the microprocessor and sensor data acquisition and storage components, which collect and analyze the data measured by the sensor assembly 300 and transmit the data according to preset parameters and function commands, including alarm functions. The upper circuit board is configured for communication, including wireless functions such as Bluetooth Low Energy, Wi-Fi, NB-IoT, LoRaWAN, 3G / 4G / 5G, and CAT-M. NB-IoT is preferred. The control circuit board (control circuit printed circuit board 500) is fixed to the mounting studs 510 provided on the detection equipment base 220 using the second set of screws 522.

[0104] Continue with the manufacturing method, refer to Figure 5 The top cover 600 of the battery compartment 610 of the testing equipment is placed on the base 220 of the testing equipment by a third screw set 620. Preferably, a sealing ring is provided between the base 220 and the top cover 600 to ensure the required level of protection.

[0105] After the city gas safety testing equipment is installed on the gas pipeline, before starting use, place the battery in the battery compartment 610 of the top cover 600, and use the manual screw set 614 to fix and lock the battery compartment cover 612 to the equipment to ensure the normal operation of the equipment.

[0106] After the city gas safety testing equipment is manufactured, it should be referenced... Figure 6 Its upper cover 600 includes a gas flow pattern indicator 648 and a working status indicator 645 for the detection equipment. A manual low-power active valve reset button 642 is also located on the upper cover 600. Pressing the button opens the low-power motor valve. The manual valve opening function is a protection function that triggers valve closure due to a fault when the network connection is temporarily unavailable due to external reasons. After manual intervention to troubleshoot and repair the fault, the valve can be manually opened, allowing downstream gas equipment to operate normally.

[0107] The testing equipment for safe use of urban gas obtained using the above manufacturing method can serve as a powerful tool for ensuring the safe use of residential gas. Combined with its comprehensive metering function, it can further improve the management level of residential gas.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for detecting the gas status of urban residential gas pipelines, characterized in that, include: The system includes a sensor assembly (300) with a microelectromechanical system (MEMS) flow sensor (100) and a pressure sensor, a detection channel (210), a substrate (220), a rectifier (310), a low-power motor valve, and a control circuit printed circuit board (500). The rectifier (310) and the low-power motor valve are both installed in the detection channel (210). The sensor assembly (300) is installed on the rectifier (310). The substrate (220) is installed on the detection channel (210). The control circuit printed circuit board (500) is installed on the substrate (220). The sensor assembly (300) and the low-power motor valve are both electrically connected to the control circuit printed circuit board (500).

2. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, The microelectromechanical system (MEMS) flow sensor (100) includes a silicon substrate (105), a micro heater (110), an upstream temperature sensor (120), a downstream temperature sensor (130), and a temperature sensor (140). The micro heater (110), the upstream temperature sensor (120), the downstream temperature sensor (130), and the temperature sensor (140) are all mounted on the silicon substrate (105). The micro heater (110) is located between the upstream temperature sensor (120) and the downstream temperature sensor. Between the devices (130), a heat insulation cavity (150) is provided on the silicon substrate (105), and a silicon nitride thin film is provided at the heat insulation cavity (150). The micro heater (110), the upstream temperature sensor (120), and the downstream temperature sensor (130) are all located above the silicon nitride thin film. The micro heater (110), the upstream temperature sensor (120), the downstream temperature sensor (130), and the temperature sensor (140) are all electrically connected to the control circuit printed circuit board (500).

3. The device for detecting the gas status of urban residential gas pipelines according to claim 2, characterized in that, The thickness of the silicon nitride film ranges from 0.8 to 2 micrometers. A passivation layer is provided on the micro heater (110), the upstream temperature sensor (120), and the downstream temperature sensor (130). The thickness of the passivation layer ranges from 0.5 to 1.2 micrometers. There is a gap between the micro heater (110), the upstream temperature sensor (120), and the downstream temperature sensor (130).

4. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, The rectifier (310) is located at the outlet end of the detection channel (210). The rectifier (310) includes at least one inner cylinder (312) and at least one outer cylinder (314). The outer cylinder (314) is sleeved on the outside of the inner cylinder (312). The detection channel (210) is sleeved on the outside of the inner cylinder (312). The inner cylinder (312) and the outer cylinder (314) are coaxial. The microelectromechanical system flow sensor (100) is located in the middle of the inner cylinder (312). The surface of the microelectromechanical system flow sensor (100) is perpendicular to the axis of the inner cylinder (312). A metal filter screen (316) is provided on one side of the rectifier (310). The mesh size of the metal filter screen (316) is in the range of 80~300.

5. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, The rectifier component (310) is mounted on the detection channel (210) by means of a nut (326) and a sealing ring, and the sensor assembly (300) is electrically connected to the control circuit printed circuit board (500) by means of a pin header (328).

6. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, The low-power motor valve is located at the outlet end of the detection channel (210). The low-power motor valve includes an active component (400) and a passive component (410). The active component (400) is mounted on the base (220), and the passive component (410) is mounted in the detection channel (210). The active component (400) and the passive component (410) are connected in a transmission manner, and the active component (400) is electrically connected to the control circuit printed circuit board (500).

7. The device for detecting the gas status of urban residential gas pipelines according to claim 6, characterized in that, The active component (400) includes a linkage gear set (402) and a screw (405). The passive component (410) includes a valve (412), a motor valve spring (415), and a body (418). The linkage gear set (402) is mounted on the base (220) and is electrically connected to the control circuit printed circuit board (500). The screw (405) is rotatably mounted on the linkage gear set (402). The screw (405), the valve (412), the motor valve spring (415), and the body (418) are all mounted in the detection flow channel (210). The valve (412) is located on the rotation trajectory of the screw (405). The motor valve spring (415) is connected to the valve (412). The body (418) is located on the movement trajectory of the motor valve spring (415).

8. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, The control circuit printed circuit board (500) includes: a microprocessor, sensor data acquisition and storage components, and a wireless data transmitter. The microelectromechanical system flow sensor (100) and the sensor assembly (300) of the pressure sensor are both electrically connected to the sensor data acquisition and storage components. The sensor data acquisition and storage components and the wireless data transmitter are both electrically connected to the microprocessor. The microprocessor is electrically connected to an alarm device. The wireless data transmitter is wirelessly connected to a gas data control center and the user's mobile device.

9. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, A top cover (600) is mounted on the base (220). A battery compartment (610) is provided on the top cover (600). A power supply battery (700) is provided in the battery compartment (610). A battery compartment cover (612) is provided at the battery compartment (610). The power supply battery (700) is electrically connected to the control circuit printed circuit board (500). A gas flow mode indicator (648), a working status indicator (645), and a manual low-power active valve reset button (642) are provided on the top cover (600). The working status indicator (645) and the manual low-power active valve reset button (642) are both electrically connected to the control circuit printed circuit board (500).

10. The device for detecting the gas status of urban residential gas pipelines according to claim 1, characterized in that, Both ends of the detection channel (210) are provided with movable connectors (810) for connecting in series with the main gas pipeline.

Images