Leakage diagnosis module

Abstract

The invention relates to the technical field of automobiles, in particular to a leakage diagnosis module. The invention provides a leakage diagnosis module which at least comprises a supporting shell, an air pump, an electromagnetic valve, a pressure sensor assembly and an upper cover plate. The supporting shell is internally provided with a pressure cavity and an electromagnetic valve cavity which are communicated through an airflow channel; the air pump is used for pumping air from the outside atmosphere to the pressure cavity or pumping air in the pressure cavity to the outside atmosphere through the atmosphere interface; the electromagnetic valve is used for controlling on-off of a gas path between the to-be-diagnosed equipment and the gas flow channel; the pressure sensor assembly is installed in the pressure cavity in the supporting shell and used for collecting pressure signals in the pressure cavity; the upper cover plate is fixedly connected with the supporting shell in a sealed mode. The pressure sensor assembly and the air pump are arranged in the pressure cavity in the supporting shell together, so that the number of parts and assembly links are greatly reduced, the product structure is more compact, and the overall airtightness and reliability of the product are improved.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and more particularly to a leakage diagnosis module. Background Art

[0002] With the rapid development of the global automotive industry, automotive environmental regulations are becoming increasingly stringent, particularly regarding the increasing control of fuel vapor emissions. Against this backdrop, fuel vapor leak diagnostic modules, as a key component of automotive emission control systems, are playing an increasingly important role in reducing vehicle emissions and air pollution. The core function of a fuel vapor leak diagnostic system is to test the airtightness of the fuel tank and fuel vapor recovery system (such as the carbon canister and connecting lines) to determine if there is a fuel vapor leak, effectively preventing the escape of fuel vapor into the atmosphere and causing environmental pollution.

[0003] The oil and gas leakage diagnosis products in the existing technology have some inherent structural and performance defects in actual application, which seriously restrict the accuracy, stability and economy of oil and gas leakage diagnosis.

[0004] One oil and gas leak diagnostic module utilizes a motor-driven rotor pump for diagnosis, using the motor current as the diagnostic signal. This diagnostic signal is derived directly from the motor that drives the product. However, the motor's output current is susceptible to interference from various factors, including changes in motor load, motor placement, and external mechanical vibration. These interference factors frequently occur in complex vehicle environments, resulting in poor current diagnostic stability in the oil and gas leak diagnostic module and difficulty ensuring reliable diagnostic results. Furthermore, the motor-driven rotor pump generates noticeable noise during operation.

[0005] Another oil and gas leak diagnostic module uses a brushless motor, which is more expensive than traditional motors. Its diagnostic mechanism relies on a pressure sensor to collect internal pressure signals and analyze and detect them to determine if there is a leak. However, since the pressure sensor in this oil and gas leak diagnostic module needs to be separately integrated into a supporting sub-component, this not only increases the number of parts in the product, making the structure more complex, but also further increases the product cost.

[0006] The third type of oil and gas leak diagnosis module relies on a motor-driven air pump. Due to its operating characteristics, it must be equipped with a diaphragm pump with extremely strong pressure-building capabilities. However, during actual operation, this diaphragm pump generates extremely loud noise, which also limits the product's application scenarios to a certain extent.

[0007] Therefore, given the many problems existing in existing on-board oil and gas leak diagnosis products in terms of structural design, performance, and cost control, there is an urgent need to propose a new oil and gas leak diagnosis technology solution to meet the increasingly stringent automotive environmental protection regulations and market demands. Summary of the Invention

[0008] The purpose of the present invention is to provide a leakage diagnosis module to solve the technical problems of the leakage diagnosis module in the prior art, such as the complex structure and the great difficulty in assembly.

[0009] Another object of the present invention is to provide a leakage diagnosis module to solve the technical problems of the leakage diagnosis module in the prior art, such as high noise and poor diagnostic stability.

[0010] To achieve the above objectives, the present invention provides a leakage diagnosis module, which includes at least a support housing, an air pump, a solenoid valve, a pressure sensor assembly, and an upper cover plate:

[0011] The support housing is provided with a pressure chamber and a solenoid valve chamber inside, and the pressure chamber and the solenoid valve chamber are connected through an air flow channel;

[0012] The support housing is provided with a diagnostic interface for connecting to the device to be diagnosed and an atmospheric interface for connecting to the outside atmosphere;

[0013] The solenoid valve chamber is connected to the device to be diagnosed through a diagnostic interface;

[0014] The air pump is installed in the pressure chamber inside the support shell, and draws gas from the outside atmosphere through the atmospheric interface to pump gas into the pressure chamber or pumps gas in the pressure chamber into the outside atmosphere;

[0015] The solenoid valve is installed in the solenoid valve cavity inside the supporting shell and is used to control the on-off of the air path between the device to be diagnosed and the pressure cavity;

[0016] The pressure sensor assembly is installed in the pressure chamber inside the support shell and is used to collect the pressure signal inside the pressure chamber;

[0017] The upper cover plate is fixedly connected to the supporting shell through sealing.

[0018] In some embodiments, the pressure sensor assembly includes a pressure sensor and a circuit board. The pressure sensor is soldered to the circuit board using surface mount technology and is electrically connected to an electrical circuit on the circuit board.

[0019] In some embodiments, the air pump is a piezoelectric ceramic pump.

[0020] In some embodiments, the pressure sensor assembly is further provided with electronic components for driving the air pump, which are electrically connected to the PIN needle structure of the air pump to drive the air pump to work.

[0021] In some embodiments, a fluid interface of the air pump housing communicating with an atmospheric interface is provided on the side wall of the pressure chamber;

[0022] The air inlet end of the air pump is connected to the fluid interface of the air pump housing, and the air outlet end of the air pump is connected to the pressure chamber, and is used to extract gas from the external atmosphere and pump gas into the pressure chamber; or

[0023] The air outlet end of the air pump is connected to the fluid interface of the air pump housing, and the air inlet end of the air pump is communicated with the pressure chamber, so as to pump the gas in the pressure chamber into the external atmosphere.

[0024] In some embodiments, when the solenoid valve is in an open state, the air path between the device to be diagnosed and the air flow channel is connected;

[0025] When the air pump extracts gas from the outside atmosphere and pumps it into the pressure chamber:

[0026] The external gas passes through the fluid interface of the air pump housing, the air pump, the pressure chamber, the air flow channel, the solenoid valve chamber, and the diagnostic interface to the device to be diagnosed, forming a diagnostic loop;

[0027] When the air pump pumps the gas in the pressure chamber to the outside atmosphere, the gas flow path of the diagnostic circuit is opposite to that when the air is extracted from the outside atmosphere and pumped into the pressure chamber.

[0028] In some embodiments, the support shell is further provided with a reference hole and a solenoid valve shell fluid interface on the solenoid valve cavity side, the reference hole is used to connect the airflow channel and the solenoid valve cavity, and the solenoid valve shell fluid interface is connected to the atmospheric interface.

[0029] In some embodiments, the solenoid valve is in a closed state, the air path between the external device to be diagnosed and the air flow channel is cut off, and the air path between the fluid interface of the solenoid valve housing and the reference hole is connected;

[0030] When the air pump extracts gas from the outside atmosphere and pumps it into the pressure chamber:

[0031] The external gas passes through the fluid interface of the air pump housing, the air pump, the pressure chamber, the air flow channel, the reference hole, the solenoid valve chamber in sequence, and returns to the external atmosphere through the fluid interface of the solenoid valve housing to form a reference circuit;

[0032] The gas flow path of the reference circuit when the air pump pumps the gas in the pressure chamber to the outside atmosphere is opposite to that when the air is extracted from the outside atmosphere and pumped into the pressure chamber.

[0033] In some embodiments, the air pump housing fluid interface and the solenoid valve housing fluid interface are disposed on the same side of the support housing and are in communication with the atmosphere interface.

[0034] In some embodiments, the air flow channel is formed integrally with the support housing, and one end is an open end;

[0035] The open end is provided with a plug:

[0036] The plug is in sealing cooperation with the air flow channel to close the open end.

[0037] In some embodiments, the support shell is provided with a first welding rib, and the upper cover is provided with a second welding rib at a corresponding position;

[0038] The first welding rib and the second welding rib are connected by welding to form a pressure chamber and a solenoid valve chamber structure.

[0039] The present invention provides a leakage diagnosis module, which eliminates the separate sensor cavity by arranging the pressure sensor assembly together with the air pump in the pressure cavity inside the supporting shell, and adopts an integrally formed air path structure, thereby greatly reducing the number of parts and assembly links, making the product structure more compact, and improving the overall air tightness and reliability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, in which like reference numerals denote like features throughout, wherein:

[0041] Figure 1 A schematic diagram of components of a leakage diagnosis module according to an embodiment of the present invention is disclosed;

[0042] Figure 2a A front view of a leakage diagnosis module according to an embodiment of the present invention is disclosed;

[0043] Figure 2b A top view of a leakage diagnostic module according to an embodiment of the present invention is disclosed;

[0044] Figure 3a Revealed Figure 2a a cross-sectional view along a first longitudinal depth;

[0045] Figure 3b Revealed Figure 2b a cross-sectional view along a second longitudinal depth;

[0046] Figure 3c Revealed Figure 3b Schematic diagram of the middle plug separation state;

[0047] Figure 4a A front view of an air pump according to an embodiment of the present invention is disclosed;

[0048] Figure 4b A side view of an air pump according to an embodiment of the present invention is disclosed;

[0049] Figure 5 A schematic diagram of an upper cover plate according to an embodiment of the present invention is disclosed;

[0050] Figure 6a A schematic diagram of a pressure sensor assembly according to an embodiment of the present invention is disclosed;

[0051] Figure 6b A schematic diagram of a solenoid valve according to an embodiment of the present invention is disclosed;

[0052] Figure 7a A schematic diagram of an airflow of a leakage diagnosis module in a reference phase according to an embodiment of the present invention is disclosed;

[0053] Figure 7b Revealed Figure 7a a cross-sectional view of a first longitudinal depth;

[0054] Figure 7c Revealed Figure 7a a cross-sectional view taken at a second longitudinal depth;

[0055] Figure 8a A schematic diagram of an airflow of a leakage diagnosis module in a diagnosis phase according to an embodiment of the present invention is disclosed;

[0056] Figure 8b Revealed Figure 8a a cross-sectional view of a first longitudinal depth;

[0057] Figure 8c Revealed Figure 8a a cross-sectional view taken at a second longitudinal depth;

[0058] Figure 9 A structural schematic diagram of a piezoelectric ceramic pump structure according to an embodiment of the present invention is disclosed.

[0059] The meanings of the reference numerals in the figures are as follows:

[0060] 1 supporting shell;

[0061] 11 solenoid valve chamber;

[0062] 111 diagnostic interface;

[0063] 112 solenoid valve sealing hole;

[0064] 113 reference holes;

[0065] 114 solenoid valve housing fluid interface;

[0066] 115 plug;

[0067] 12 pressure chamber;

[0068] 121 air pump housing fluid interface;

[0069] 122 second PIN needle structure;

[0070] 130 laser welding ribs;

[0071] 140 air flow channels;

[0072] 2 air pumps;

[0073] 21 air pump air inlet;

[0074] 22 air pump outlet;

[0075] 23 sealing ring;

[0076] 24 second connecting terminal;

[0077] 25 third PIN needle structure;

[0078] 261 upper one-way valve;

[0079] 262 Metal Oscillator;

[0080] 263 glue;

[0081] 264 flexible circuit board;

[0082] 265 piezoelectric ceramics;

[0083] 266 lower one-way valve;

[0084] 267 upper shell;

[0085] 268 lower shell;

[0086] 3. Solenoid valve;

[0087] 31 first connecting terminal;

[0088] 4 pressure sensor assembly;

[0089] 41 pressure sensor;

[0090] 5. Upper cover;

[0091] 51 laser welding ribs;

[0092] 52 fourth PIN needle structure;

[0093] 53 electrical interface. DETAILED DESCRIPTION

[0094] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the invention and are not intended to limit the invention.

[0095] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from the description, so the present invention is not limited to the specific embodiments disclosed below.

[0096] The following describes embodiments of the present invention with reference to the accompanying drawings. However, the embodiments described below are examples of leak diagnosis modules for embodying the technical concept of the present invention, and the leak diagnosis module of the present invention is not limited to the following contents.

[0097] In response to the problems of complex structure, high noise, high cost and poor diagnostic stability in the existing oil and gas leakage diagnosis module, the present invention proposes a leakage diagnosis module for oil and gas leakage detection in automobile fuel tank systems and their associated pipelines. It has the advantages of small size, low noise, high stability and high structural integration.

[0098] Figure 1 A schematic diagram of components of a leakage diagnosis module according to an embodiment of the present invention is disclosed. Figure 1 As shown, the leakage diagnosis module proposed in the present invention comprises at least a supporting shell 1, an air pump 2, a solenoid valve 3, a pressure sensor assembly 4 and an upper cover plate 5.

[0099] The support housing 1 is used to carry and install the remaining components in the module, and is provided with a pressure chamber 12 and a solenoid valve chamber 11 inside. The pressure chamber 12 and the solenoid valve chamber 11 are connected through an air flow channel 140;

[0100] The support housing 1 is provided with a diagnostic interface 111 for connecting to the device to be diagnosed and an atmospheric interface for connecting to the outside atmosphere;

[0101] The solenoid valve chamber 11 is connected to the device to be diagnosed through the diagnostic interface 111;

[0102] The air pump 2 is installed in the pressure chamber 12 inside the support shell 1, and draws gas from the outside atmosphere through the atmospheric interface to pump gas into the pressure chamber 12 or pumps gas in the pressure chamber 12 into the outside atmosphere;

[0103] The solenoid valve 3 is installed in the solenoid valve chamber 11 inside the supporting housing 1 and is used to control the on / off of the air path between the device to be diagnosed and the pressure chamber 12;

[0104] The pressure sensor assembly 4 is installed in the same cavity as the air pump 2, that is, in the pressure cavity 12 inside the support shell 1, located between the air pump 2 and the upper cover plate 5, for collecting the pressure signal inside the pressure cavity 12;

[0105] The upper cover plate 5 is fixedly connected to the supporting shell 1 through sealing.

[0106] The leakage diagnosis module proposed in the present invention realizes an integrated design by installing the pressure sensor assembly 4 and the air pump 2 in the same cavity, which not only simplifies the system structure and improves the detection accuracy and response speed, but also enhances the overall shock resistance and sealing reliability.

[0107] In this embodiment, a fuel tank system is used as a typical example of a device to be diagnosed, but the application scope of the leakage diagnosis module is not limited to the fuel system.

[0108] In fact, this leak diagnosis module is also applicable to other types of closed or semi-closed systems that require airtightness testing, including but not limited to pipes and carbon canisters in fuel supply systems, refrigerant pipes and evaporators in refrigeration systems, brake pipes and cylinders in hydraulic or pneumatic systems, as well as various sealed containers and fluid delivery systems.

[0109] Figure 2a and Figure 2b The front view and top view of the leakage diagnosis module according to an embodiment of the present invention are disclosed respectively. Figure 3a 、 Figure 3b Respectively revealed Figure 2a A cross-sectional view along a first longitudinal depth and a second longitudinal depth, Figure 3c Revealed Figure 3b The schematic diagram of the plug separation state is shown below. Figures 2a to 3c , describe the specific components of the leakage diagnosis module proposed in the present invention.

[0110] In this embodiment, the supporting shell 1 mainly functions as an installation carrier for other functional components such as the air pump 2, the solenoid valve 3, and the pressure sensor assembly 4, and forms a pressure chamber 12 and a solenoid valve chamber 11 inside the structure. Through its own complex internal air path structure, it collaboratively completes the gas circulation in the reference stage and the diagnosis stage, and realizes effective guidance and sealing control of the air path.

[0111] From the perspective of structural division, the support housing 1 is mainly divided into two areas, namely the solenoid valve chamber 11 and the pressure chamber 12:

[0112] The solenoid valve chamber 11 is the solenoid valve installation side, used for installing the solenoid valve 3;

[0113] The pressure chamber 12 is the installation side of the air pump 2 and the pressure sensor assembly 4 and is used for installing the air pump 2 and the pressure sensor assembly 4 .

[0114] In terms of gas path design, various gas paths are set up inside the support shell 1, connecting the pressure chamber 12, the solenoid valve chamber 11 and various functional interfaces (including the air pump housing fluid interface 121, the diagnostic interface 111, the reference hole 113, etc.) separately or mutually to form a complete gas flow path, ensuring that the system can achieve stable and reliable airflow control in both the reference stage and the diagnostic stage.

[0115] like Figure 2a and Figure 2b As shown, the support housing 1 is provided with an air pump housing fluid interface 121 which is in communication with the atmospheric interface.

[0116] More specifically, the air pump housing fluid interface 121 is located on the side wall of the pressure chamber 12 and is connected to both the air pump air inlet 21 and the atmospheric interface;

[0117] The support housing 1 is provided with a solenoid valve housing fluid interface 114, which is arranged on the side wall of the solenoid valve cavity 11 and corresponds to the airway of the solenoid valve 3, and is connected to the atmospheric interface, thereby achieving communication with the outside atmosphere.

[0118] The air pump housing fluid interface 121 and the solenoid valve housing fluid interface 114 are arranged on the same side of the support housing 1 .

[0119] The support housing 1 is provided with a diagnostic interface 111 on the side of the solenoid valve chamber 11:

[0120] The diagnostic interface 111 is provided at the end of the solenoid valve chamber 11 and controls the connection and disconnection with the external fuel tank system through the solenoid valve 3;

[0121] The support housing 1 is provided with a reference hole 113 on the side of the solenoid valve cavity 11, which is located between the solenoid valve cavity 11 and the air flow channel 140:

[0122] The reference hole 113 is used to connect the solenoid valve chamber 11 and the air flow channel 140 to establish a reference circuit in the reference stage, so that the gas can form a gas passage between the pressure chamber 12 and the solenoid valve chamber 11 through the reference hole 113.

[0123] The support housing 1 is provided with a solenoid valve sealing hole 112 on the side of the solenoid valve cavity 11, which is located between the solenoid valve cavity 11 and the air flow channel 140:

[0124] The solenoid valve sealing hole 112 is used to connect the air flow channel 140 and the solenoid valve chamber 11 .

[0125] The solenoid valve sealing hole 112 forms a dynamic seal with the valve core of the solenoid valve 3. When the solenoid valve is powered on, a gas channel is formed to connect to the oil tank system. When the solenoid valve is powered off, the channel is cut off to isolate the gas paths inside and outside the system.

[0126] The solenoid valve 3 controls the solenoid valve sealing hole 112 to close, cuts off the air path between the diagnostic interface 111 and the air flow channel 140, and keeps the solenoid valve chamber 11 in communication with the air flow channel 140 through the reference hole 113. At the same time, the solenoid valve chamber 11 keeps in communication with the outside atmosphere, forming a reference circuit.

[0127] The solenoid valve 3 controls the solenoid valve sealing hole 112 to open, so that the diagnostic interface 111 is connected to the air flow channel 140 to form a diagnostic loop.

[0128] The pressure chamber 12 and the solenoid valve chamber 11 inside the support housing 1 are connected to each other through the air flow channel 140;

[0129] The solenoid valve chamber 11 is connected to the air flow channel 140 through the reference hole 113 and the solenoid valve sealing hole 112 .

[0130] The above structures are all integrated into the supporting shell 1 by an integrated molding process. This integrated design not only ensures the real-time performance of pressure transmission, but also realizes the optimized design of the gas flow path through the series layout between the chambers.

[0131] It should be noted that the air flow channel 140 is directly formed inside the support shell 1 using an integrated forming process, and its channel direction and opening end are both set on the side wall of the support shell 1, which is completely independent of the upper cover plate 5 and does not rely on the joint surface between the support shell 1 and the upper cover plate 5.

[0132] In this embodiment, the support shell 1 is manufactured by an integrated forming process, and the internal gas path thereof is formed in one step by a mold.

[0133] The one-piece injection molding process enables the support shell 1 to have high structural strength, good airtightness and excellent dimensional consistency, providing a solid foundation for the precise installation of subsequent components and the miniaturized layout of the entire machine.

[0134] During the manufacturing process, in order to meet the requirements of the demoulding process, process openings will be formed at the end of some gas paths. These openings are non-use ports in terms of product function.

[0135] In order to prevent gas from leaking through these non-functional openings, plugs 115 are provided at the non-used ports of the support shell 1 to close the non-used gas path ports.

[0136] More specifically, the air flow channel 140 is formed integrally with the supporting housing 1 and has an open end at one end;

[0137] A plug 115 is installed at the open end:

[0138] The plug 115 is sealed with the air flow channel 140 to close the open end.

[0139] The plug 115 is made of the same material as the housing and is sealed with the housing through an ultrasonic welding process.

[0140] In order to improve the overall sealing performance of the system, the support shell 1 is provided with a first welding rib, and the upper cover plate 5 is provided with a second welding rib at the corresponding position:

[0141] The first welding rib and the second welding rib are sealed and connected by welding, forming a pressure chamber 12 and a solenoid valve chamber 11 structure in the support shell 1 .

[0142] More specifically, the first welding rib of the support shell 1 is an "8"-shaped laser welding rib 130, and the second welding rib of the upper cover plate 5 is an "8"-shaped laser welding rib 51:

[0143] The first welding rib and the second welding rib are connected by laser welding.

[0144] In this embodiment, the structural design of the “8”-shaped laser welding rib divides the support shell 1 into a pressure chamber 12 and a solenoid valve chamber 11 , and ensures a highly reliable seal between the support shell 1 and the upper cover plate 5 .

[0145] In terms of electrical design, the support housing 1 is provided with a first PIN structure (not shown in the figure) in the solenoid valve cavity 11, which corresponds to the first connection terminal 31 of the solenoid valve 3 to achieve electrical connection with the solenoid valve 3;

[0146] The support housing 1 is provided with a second PIN needle structure 122 in the pressure chamber 12 , corresponding to the second connection terminal 24 of the air pump 2 , so as to achieve electrical connection with the air pump 2 .

[0147] Furthermore, the first PIN needle structure and the second PIN needle structure are obtained by insert injection molding.

[0148] In the leakage diagnosis module proposed in the present invention, the air pump 2 serves as a main working component, providing stable pumping / exhausting capacity during operation, and is a key execution component for realizing leakage diagnosis of the fuel tank system.

[0149] Figure 4a and Figure 4b The front view and side view of the air pump according to one embodiment of the present invention are disclosed respectively. Figure 4a and Figure 4bAs shown, the air inlet end of the air pump 2 is sealedly connected to the fluid interface 121 of the air pump housing, and the air outlet end of the air pump 2 is communicated with the pressure chamber 12, for extracting gas from the external atmosphere and pumping gas into the pressure chamber 12; or

[0150] The air outlet of the air pump 2 is sealed with the fluid interface 121 of the air pump housing, and the air inlet of the air pump 2 is communicated with the pressure chamber 12 for pumping the gas in the pressure chamber 12 into the outside atmosphere.

[0151] In this embodiment, the air pump air inlet 21 of the air pump 2 is inserted into the air pump housing fluid interface 121 of the support housing 1, and the sealing of the gas path is achieved through the sealing ring 23 of the air pump itself.

[0152] In this embodiment, a third PIN needle structure 25 is provided in the housing of the air pump 2, which is electrically connected to the PIN needle socket structure of the pressure sensor assembly 4;

[0153] A second connection terminal 24 is provided in the housing of the air pump 2 and is electrically connected to the second PIN needle structure of the supporting housing 1 .

[0154] Furthermore, the third PIN needle structure 25 is obtained by insert injection molding.

[0155] Figure 5 A schematic diagram of an upper cover plate according to an embodiment of the present invention is disclosed. Figure 5 As shown, the upper cover plate 5 is not only used as a packaging component, but also plays a key role in electrical connection and regional isolation.

[0156] In this embodiment, the upper cover plate 5 is provided with a fourth PIN pin structure 52, which is electrically connected to the PIN pin socket structure of the pressure sensor assembly 4;

[0157] like Figure 1 As shown, the upper cover 5 is provided with an electrical interface 53, which aggregates all pathways of the fourth PIN needle structure to form a unified electrical port (connector) to the outside, thereby achieving electrical conduction between the external power supply and the internal circuit, thereby ensuring normal operation of the system.

[0158] In this embodiment, the electrical interface 53 integrated in the upper cover plate 5 is connected to all electrical signal paths of the fourth PIN needle structure 52 through multi-layer PCB wiring (not shown).

[0159] like Figure 5As shown, the upper cover plate 5 is precisely welded to the welding ribs at the corresponding positions on the support shell 1 by setting "8"-shaped laser welding ribs 51, which not only achieves a stable connection between the upper cover plate 5 and the support shell 1, but also effectively divides the interior of the support shell 1 into two areas: the solenoid valve chamber 11 and the pressure chamber 12. While ensuring the structural sealing, it provides important support for the reliable operation of the entire leakage diagnosis module.

[0160] Figure 6a A schematic diagram of a pressure sensor assembly according to an embodiment of the present invention is disclosed. Figure 6a As shown, the pressure sensor assembly 4 includes a pressure sensor 41 and a circuit board. The pressure sensor 41 is soldered on the circuit board through surface mounting technology and is electrically connected to the electrical circuit on the circuit board.

[0161] Surface mount technology may include reflow soldering, wave soldering, laser welding and other surface mount processes that can achieve electrical connection between the pressure sensor 41 and the circuit board.

[0162] In this embodiment, the pressure sensor assembly 4 is a circuit board assembly (PCBA), and the pressure sensor assembly 4 integrates a pressure sensor 41 for collecting the pressure signal inside the pressure chamber 12 .

[0163] More specifically, the pressure sensor 41 is fixed to the circuit board of the pressure sensor assembly 4 by reflow soldering and is electrically connected to the electrical circuit on the circuit board.

[0164] The reflow soldering method is a surface mounting process that heats the solder paste to melt it, and then solders and fixes electronic components such as pressure sensors on the pads of the circuit board to achieve mechanical connection and electrical conduction.

[0165] Furthermore, the pressure sensor assembly 4 is provided with a PIN pin socket structure, which is connected to the PIN pin structure of the air pump 2 and the upper cover plate 5.

[0166] The above-mentioned PIN connection method simplifies wiring, improves assembly consistency and airtightness control accuracy, and also provides a stable power supply and signal path for the system.

[0167] In this embodiment, the pressure sensor assembly 4 is responsible for the important function of pressure monitoring.

[0168] Furthermore, the pressure sensor assembly 4 is also provided with electronic components for driving the air pump, which are electrically connected to the PIN needle structure of the air pump 2 for driving the air pump 2 to work.

[0169] More specifically, air pump 2 is activated under the logical control of pressure sensor assembly 4, establishing and maintaining airflow in the pressure chamber. Simultaneously, pressure sensor 41 collects real-time air pressure data, providing critical pressure parameters for fuel tank leak diagnosis, thereby ensuring high-performance and stable operation of the entire leak diagnosis module.

[0170] If the pressure sensor assembly 4 is not equipped with electronic components for driving the air pump, the air pump 2 can be driven by an external vehicle drive controller.

[0171] Figure 6b A schematic diagram of a solenoid valve according to an embodiment of the present invention is disclosed. Figure 6b As shown, in this embodiment, the solenoid valve 3 is a press-fit installation structure and is fixedly installed in the solenoid valve cavity 11;

[0172] The support housing 1 is provided with a solenoid valve sealing end in the solenoid valve cavity 11 , which corresponds to the sealing structure of the solenoid valve 3 to achieve sealing of the solenoid valve.

[0173] Specifically, the sealing structure of the solenoid valve 3 is aligned with and fits the sealing end of the solenoid valve in the supporting shell to form a stable and reliable seal, thereby effectively preventing gas leakage during the pumping / vacuuming process, ensuring the airtightness and stable operation of the entire module, and thus ensuring the accuracy and reliability of the leakage diagnosis results.

[0174] At the same time, the first connection terminal 31 of the solenoid valve 3 is precisely aligned with the first PIN needle structure injected into the supporting shell 1 to achieve electrical conduction between the solenoid valve 3 and the pressure sensor assembly 4.

[0175] The present invention adopts multiple sets of precise PIN needle structure design in terms of electrical connection, specifically including:

[0176] The first and second PIN pin structures 122 are insert-molded on the supporting housing 1;

[0177] A third PIN needle structure 25 is provided inside the housing of the air pump 2;

[0178] The fourth PIN needle structure 52 integrated in the upper cover plate 5 and the PIN needle structure connecting the pressure sensor 41 and the pressure sensor assembly 4 are also included.

[0179] This multi-level PIN interconnection system forms a three-dimensional electrical transmission network. The insulation and positioning accuracy between each PIN pin and the shell are ensured through the insert injection molding process. It not only realizes high-speed signal transmission between the air pump 2, solenoid valve 3, pressure sensor 41 and pressure sensor assembly 4, but also reduces assembly time through modular plug-in design. At the same time, it avoids the risk of poor contact caused by traditional wiring harness connection, and significantly improves the connection reliability and environmental adaptability of the module in harsh environments such as vehicle vibration.

[0180] The leakage diagnosis module proposed in the present invention uses the air pump 2 as the core executive element, combined with other functional components in the module, to achieve high-precision oil and gas leakage diagnosis of the entire vehicle tank system.

[0181] The leakage diagnosis module proposed in the present invention is mainly divided into two working stages: the first stage is a reference stage, and the second stage is a diagnosis stage.

[0182] The reference phase precedes the diagnostic phase and is used to verify the stability of the pumping / exhausting capabilities of the leak diagnostic module's own air pump, providing reliable benchmark conditions for the subsequent diagnostic phase.

[0183] The diagnostic phase is used to test the fuel tank system for oil and gas leaks. Two different diagnostic modes are available: the first diagnostic mode and the second diagnostic mode. When the second diagnostic mode is used, the reference phase is bypassed and the system enters the diagnostic phase directly.

[0184] The reference phase is usually carried out before the vehicle's fuel tank system is involved. The process is highly closed and controllable, which helps to eliminate the interference of leakage from the leak diagnosis module itself on the diagnosis results.

[0185] Figure 7a The flow diagram of the leakage diagnosis module in the reference phase according to one embodiment of the present invention is disclosed. Figure 7b and Figure 7c Respectively revealed Figure 7a A cross-sectional view of a first longitudinal depth and a second longitudinal depth, such as Figures 7a to 7c As shown, in the reference phase, a relatively independent and closed reference loop is constructed inside the leakage diagnosis module. When the leakage diagnosis module is in the reference phase;

[0186] The solenoid valve 3 is in a closed state, cutting off the air path between the external fuel tank system and the air flow channel 140 , thereby isolating the communication path between the leakage diagnosis module and the external fuel tank system;

[0187] The air path between the solenoid valve housing fluid interface 114 and the solenoid valve chamber 11 is in a communicating state;

[0188] The air pump 2 performs pressurized pumping or decompressed air extraction operations on the reference circuit formed inside the leak diagnosis module in positive pressure mode or negative pressure mode;

[0189] During the entire process, the pressure sensor 41 integrated in the pressure sensor assembly 4 continuously collects the air pressure data inside the pressure chamber 12 to evaluate the performance of the leakage diagnosis module itself;

[0190] Among them, the positive pressure mode is to extract external gas to pressurize the cavity, and the negative pressure mode is to suck gas into the cavity to form negative pressure. The gas flow direction of the reference circuit is opposite in the positive pressure mode and the negative pressure mode.

[0191] When the air pump 2 is in positive pressure mode, the air pump 2 draws gas from the outside atmosphere and pumps gas into the pressure chamber 12:

[0192] like Figure 7b and Figure 7c The direction of the arrow is the gas flow direction. The external gas passes through the air pump housing fluid interface 121, the air pump 2, the pressure chamber 12, the air flow channel 140, the reference hole 113, the solenoid valve chamber 11, and returns to the external atmosphere through the solenoid valve housing fluid interface 114 to form a reference circuit.

[0193] The gas flow path of the reference circuit when the air pump 2 pumps the gas in the pressure chamber 12 to the outside atmosphere is opposite to that when the air is extracted from the outside atmosphere and pumped into the pressure chamber 12 .

[0194] More specifically, the reference circuit of the reference phase includes the intake path, the diffusion path, and the self-test outlet path in sequence:

[0195] The air intake path includes: the external air passes through the air pump housing fluid interface 121, the air pump 2, and enters the pressure chamber 12 in sequence. Figure 7a and Figure 7b As shown;

[0196] The diffusion path includes: after being compressed by the air pump 2, the gas in the pressure chamber 12 diffuses and infiltrates into the key component area, and the key components include the pressure sensor assembly 4 and the pressure sensor 41 integrated on the pressure sensor assembly 4;

[0197] The self-test gas outlet path includes: the gas passes through the pressure chamber 12, the air flow channel 140, the reference hole 113, flows through the solenoid valve housing fluid interface 114 and then returns to the outside atmosphere. Figure 7a and Figure 7c As shown;

[0198] The air inlet path, the diffusion path and the self-test air outlet path constitute an air flow path for internal self-test during the reference phase.

[0199] By collecting and analyzing air pressure data in the reference stage, the system's own pumping / exhaust capacity and sealing status can be effectively determined, providing a reliable reference for the next stage of tank leak diagnosis, ensuring the accuracy of the final diagnostic results and the long-term stability of the system.

[0200] During the diagnostic phase, two diagnostic methods—the first and second—are available, depending on specific needs, to accurately assess the fuel tank system's oil and gas tightness. These two diagnostic methods maintain the same gas flow path but differ slightly in their pressure collection and determination methods, adapting to different vehicle platforms and system integration solutions.

[0201] Figure 8a The following discloses an airflow diagram of a leakage diagnosis module in the diagnosis stage according to an embodiment of the present invention. Figure 8b and Figure 8c Respectively revealed Figure 8a A cross-sectional view of a first longitudinal depth and a second longitudinal depth, such as Figures 8a to 8c As shown, when the leakage diagnosis module is in the diagnosis stage;

[0202] The solenoid valve 3 is in the open state, the diagnostic interface 111 of the support housing 1 is connected, and the external tank system is in communication with the air passage of the air flow channel 140;

[0203] The air path between the solenoid valve housing fluid interface 114 and the solenoid valve chamber 11 is in a cut-off state;

[0204] The air pump 2 performs pressurized pumping or decompressed air extraction operations on the diagnostic circuit from the leak diagnosis module to the fuel tank system in positive pressure mode or negative pressure mode;

[0205] The air pressure data is collected by the pressure sensor 41 integrated in the pressure sensor assembly 4 or the pressure sensor in the fuel tank system to obtain the air pressure monitoring result so as to evaluate the oil and gas sealing performance of the fuel tank system.

[0206] Among them, the positive pressure mode is to extract external gas to pressurize the cavity, and the negative pressure mode is to suck gas into the cavity to form negative pressure. The gas flow direction of the diagnostic circuit is opposite in the positive pressure mode and the negative pressure mode.

[0207] When the air pump 2 is in positive pressure mode, the air pump 2 draws gas from the outside atmosphere and pumps gas into the pressure chamber 12:

[0208] like Figure 8b and Figure 8c The arrow direction is the gas flow direction. The external gas passes through the air pump housing fluid interface 121, the air pump 2, the pressure chamber 12, the air flow channel 140, the solenoid valve chamber 11, and reaches the fuel tank system through the diagnostic interface 111, forming a diagnostic loop.

[0209] When the air pump 2 pumps the gas in the pressure chamber 12 to the outside atmosphere, the gas flow path of the diagnostic circuit is opposite to that when the gas is extracted from the outside atmosphere and pumped into the pressure chamber 12 .

[0210] More specifically, the diagnostic circuit in the diagnostic phase includes the intake path, the diffusion path, and the fuel tank outlet path in sequence:

[0211] The air intake path includes: the external air passes through the air pump housing fluid interface 121, the air pump 2, and enters the pressure chamber 12 in sequence. Figure 8a and Figure 8b As shown;

[0212] The diffusion path includes: the gas in the pressure chamber 12 diffuses and infiltrates into the key component area;

[0213] The gas outlet path of the fuel tank includes: the gas passes through the pressure chamber 12, the air flow channel 140, the reference hole 113, the solenoid valve sealing hole 112 of the opened solenoid valve 3, the solenoid valve chamber 11, and then passes through the diagnostic interface 111 and is delivered to the fuel tank system, such as Figure 8c As shown;

[0214] The air intake path, the diffusion path and the fuel tank outlet path constitute an air flow path for fuel tank detection during the diagnosis stage.

[0215] The difference between the first diagnostic method and the second diagnostic method mainly lies in the operating timing and duration of the air pump 2 .

[0216] When the leak diagnosis module is in the first diagnostic mode:

[0217] Air pump 2 maintains continuous pumping / exhausting operation;

[0218] Real-time air pressure data is collected through the pressure sensor 41 or the pressure sensor in the fuel tank system;

[0219] By monitoring the pressure change trend and / or the final stable pressure value, it is possible to determine whether there is a leak in the fuel tank system.

[0220] The pressure change trend includes but is not limited to the pressure decay change trend (pressure decay rate, integral of pressure over time during pressure decay, etc.;

[0221] For example, in positive pressure mode, the air pressure change rate may be the air pressure rising rate, and in negative pressure mode, the air pressure change rate may be the air pressure falling rate.

[0222] More specifically, when the air pump 2 is in the positive pressure mode and the leakage diagnosis module is in the first diagnosis mode, the solenoid valve 3 is opened, the diagnosis interface 111 is connected, and the solenoid valve housing fluid interface 114 is cut off.

[0223] Air pump 2 begins operation, drawing in ambient air through fluid port 121 of the pump housing. Air then flows through pressure chamber 12, airflow channel 140, the opened solenoid valve 3, and reference port 113, entering solenoid valve chamber 11. After passing through diagnostic port 111, air is delivered to the fuel tank system. Air pump 2 continues pumping air into the fuel tank system. If there are no leaks in the fuel tank system, the internal pressure will continue to rise, eventually reaching a steady state.

[0224] During the whole process, the pressure sensor 41 continuously monitors the pressure value to determine the sealing performance of the system.

[0225] For example, if the pressure continues to rise over time, it means that there is no obvious leakage in the system; if the pressure rises slowly or levels off after reaching a certain threshold, or even decreases, it indicates that there is a potential leakage risk.

[0226] In this embodiment, the diameter of the reference hole 113 is set to 0.5 mm. Leak holes of different sizes will cause the monitored pressure value parameters to present different change characteristics.

[0227] When there is a leak with a diameter of 1mm or more in the fuel tank, the fuel tank pressure will stabilize at a low level of about 5-6hPa after a period of time; if there is a leak with a diameter of 0.5mm in the fuel tank, after a period of time, the fuel tank pressure can only reach the pressure value of the reference stage and cannot rise further.

[0228] In the second diagnostic mode, the air flow path of the diagnostic module is consistent with the first diagnostic mode, and the air pump 2 is not running continuously.

[0229] When the leakage diagnosis module is in the second diagnosis mode:

[0230] Air pump 2 pressurizes and pumps air / depressurizes and pumps air to the target pressure value and then stops;

[0231] The pressure sensor 41 or the pressure sensor in the fuel tank system collects air pressure data in real time to obtain the pressure change trend over time;

[0232] By monitoring the pressure change trend over time, it is possible to determine whether there is a leak in the fuel tank system.

[0233] For example, in the positive pressure mode, the pressure change trend over time may be the rate of pressure decrease over time; in the negative pressure mode, the pressure change trend over time may be the rate of pressure increase over time.

[0234] More specifically, when the air pump 2 is in the positive pressure mode and the leakage diagnosis module is in the second diagnosis mode, the solenoid valve 3 is opened, the diagnosis interface 111 is connected, and the solenoid valve housing fluid interface 114 is cut off.

[0235] The air pump 2 starts working, sucking in external air from the fluid interface 121 of the air pump housing, and after compression, sending it into the pressure chamber 12 through the air pump outlet 22, and entering the solenoid valve chamber 11 through the opened solenoid valve 3 and the reference hole 113, and after passing through the diagnostic interface 111, it is delivered to the fuel tank system.

[0236] Real-time air pressure data is collected through the pressure sensor 41 or the pressure sensor in the fuel tank system;

[0237] When the air pressure in the fuel tank system reaches the set target pressure value, the air pump 2 stops working.

[0238] The pressure sensor 41 or the pressure sensor in the fuel tank system is used to monitor the rate of change of the air pressure over time in real time, and the size of the leakage hole in the fuel tank system is estimated by analyzing the pressure change curve after the target pressure value is reached.

[0239] The second diagnostic method is particularly suitable for deployment in vehicle systems with fuel tank sensors. For example, if the fuel tank system's pressure sensor is used for leak detection, this system can omit pressure sensor 6. Furthermore, the second diagnostic method eliminates the reference stage, simplifying the module structure and cost configuration.

[0240] The leakage diagnosis module proposed in this invention accurately assesses whether there is a leak in the fuel tank system and the degree of leakage under different diagnostic methods through real-time collection and change trend analysis of pressure data, thereby meeting the compliance and safety requirements of different customers for vehicle oil and gas emission control.

[0241] It should be clear that, in the present invention, the air pump 2 can be any type of piezoelectric ceramic pump, rotor pump, diaphragm pump, vortex pump or screw pump.

[0242] As an optional embodiment, air pump 2 utilizes a piezoelectric ceramic pump. Compared to traditional motor-driven air pumps, piezoelectric ceramic pumps offer advantages such as low noise, low power consumption, fast response, and strong anti-interference capabilities, significantly improving diagnostic accuracy and environmental adaptability. In practical applications, these pumps can be further divided into two configurations: single-chamber air pumps and multi-chamber air pumps.

[0243] The single-chamber air pump has a simple structure and low cost, and is suitable for occasions where the flow rate requirement is not high;

[0244] The multi-cavity air pump can provide a smoother and continuous airflow through the design of alternating working cavities, significantly improving the working efficiency and stability of the system.

[0245] This diverse selection of pump types can adapt to pressure detection needs under different working conditions, greatly expanding the product's application range and market adaptability.

[0246] Figure 9A schematic structural diagram of a piezoelectric ceramic pump structure according to an embodiment of the present invention is disclosed. Figure 9 In the embodiment shown, the air pump 2 is a piezoelectric ceramic pump structure, which mainly includes an upper one-way valve 261, a metal vibrator 262, a flexible circuit board (FPC) 264, a piezoelectric ceramic sheet 265, a lower one-way valve 266, an upper shell 267, and a lower shell 268:

[0247] The upper one-way valve 261 is installed at the gas outlet of the upper housing 267 and only allows gas to be discharged from the pump chamber;

[0248] The metal vibrator 262 is fixedly connected to the flexible circuit board 264 and is used to amplify the vibration amplitude of the piezoelectric ceramic piece 265, periodically change the chamber volume, and promote gas flow;

[0249] The flexible circuit board 264 is fixedly installed between the upper shell 267 and the lower shell 268, dividing the pump body into two independent cavities, the upper chamber and the lower chamber, and providing driving signals for the piezoelectric ceramic piece 265;

[0250] The piezoelectric ceramic piece 265 is fixedly connected to the flexible circuit board 264 and generates high-frequency deformation when energized, driving the metal vibrator 262 to move;

[0251] The lower one-way valve 266 is installed at the air inlet of the lower housing 268 to allow only external air to enter the chamber;

[0252] The upper shell 267 and the lower shell 268 are fixedly connected by sealing.

[0253] More specifically, the piezoelectric ceramic piece 265 and the metal vibrator 262 are fixedly bonded to the flexible circuit board 264 by glue 263;

[0254] The flexible circuit board 264 is fixedly bonded to the upper shell 267 and the lower shell 268 by glue 263, thereby forming an integrated structure.

[0255] The upper shell 267 and the lower shell 268 are fixed by sealing processes such as snaps, screws or laser welding to ensure airtightness.

[0256] Because the flexible circuit board 264 is mounted between the upper and lower housings, the entire pump body is divided into two independent cavities, upper and lower. During operation, the piezoelectric ceramic 265 deforms under electrical stimulation, driving the metal vibrator 262 and the flexible circuit board 264 into high-frequency vibrations, periodically changing the volume of the upper and lower chambers. The coordinated action of the upper and lower check valves 261 and 266 ensures orderly flow of gas within the chambers, completing the intake and exhaust processes and ultimately achieving stable and effective pumping.

[0257] The piezoelectric ceramic pump has the advantages of small size and low energy consumption, and has sensitive vibration response, which is suitable for the application requirements of the leakage diagnosis module proposed in the present invention for precise delivery of trace gases and air pressure regulation.

[0258] The application of piezoelectric ceramic pumps in leak diagnosis modules has many significant advantages, especially suitable for the current situation where the vehicle has high integration and strict space utilization requirements:

[0259] First of all, the piezoelectric ceramic pump is compact and extremely suitable for confined spaces. Its core component is a piezoelectric ceramic sheet, which is usually less than 20mm in diameter and less than 1mm in thickness. Combined with the external protective shell, the entire pump body is much smaller than the rotor pump or diaphragm pump commonly used in traditional DMTL systems, with an overall volume reduction of up to 20%. This miniaturized design brings greater flexibility to the vehicle layout and can be easily installed near the fuel tank or other space-constrained areas, reducing the occupancy of the vehicle layout and reducing interference with surrounding components, which can better adapt to the structural requirements of different models.

[0260] Secondly, the piezoelectric ceramic pump has excellent NVH (noise, vibration and harshness) performance. Since the vibration frequency of the piezoelectric ceramic sheet is extremely high, far beyond the range that the human ear can detect, there is almost no perceptible noise. It has the characteristics of an "ultra-quiet pump", which effectively eliminates the noise source generated by traditional mechanical pumps, not only improving the overall quality of the vehicle, but also enhancing the user experience. At the same time, the piezoelectric ceramic pump structure has basically no obvious mechanical vibration during operation, and the amplitude of the piezoelectric ceramic sheet is only at the millimeter level, which causes less mechanical wear on its own structure and surrounding components, helping to extend its service life. In addition, since there are no violently moving components, the requirements for installation position and fixing method are relatively loose, and it can be arranged more flexibly in the vehicle, which helps to simplify the vehicle design and reduce design complexity.

[0261] Furthermore, the piezoelectric ceramic pump itself does not rely on additional mechanical drive components such as motors. Instead, it pumps air through the vibration of the piezoelectric ceramic disc itself, changing the internal volume of the chamber. Compared to existing rotor pumps or diaphragm pumps, the motorless structure of the piezoelectric ceramic pump eliminates the complex connection between the motor and the pump body, reducing assembly difficulty and system management risks. It also avoids problems such as motor oil leakage entering the rotor pump that interfere with diagnostic accuracy, thereby improving system reliability.

[0262] Finally, compared to traditional rotor pumps or diaphragm pumps, piezoelectric ceramic pumps perform better in terms of environmental tolerance. Because there are no mechanical components such as rotors, stators, and bearings that are in direct contact and produce relative motion inside the piezoelectric ceramic pump, and the upper and lower cavities are relatively large, even if external moisture and dust enter the pump body during vehicle operation, the foreign matter will not generate additional friction loads that affect the product's pumping sub-components, affecting the pumping capacity and, in turn, leak diagnosis. While achieving accurate diagnosis of fuel tank leaks, it also significantly improves stability and durability under complex working conditions.

[0263] The leakage diagnosis module proposed in the present invention has the following beneficial effects:

[0264] 1) Integrating the pressure sensor directly into the pressure sensor assembly reduces the installation space and signal interference of independent sensors, improves detection accuracy and system response speed, and enhances overall seismic resistance and sealing reliability;

[0265] 2) The PIN-type electrical design enables direct connection of the air pump, solenoid valve, and pressure sensor components, simplifying wiring, improving assembly efficiency, and enhancing electrical connection stability.

[0266] 3) The support housing adopts an integral injection-molded gas path design. By constructing the airflow channel structure between the pressure chamber and the solenoid valve chamber, it provides reliable guarantee for the orderly flow of gas during the reference and diagnostic phases.

[0267] 4) The use of a piezoelectric ceramic pump offers significant advantages over traditional structures. The elimination of the DC motor not only optimizes space layout, reduces assembly weight, and reduces operating noise, but also offers a simple and compact structure for ease of assembly, with no installation angle restrictions, greatly enhancing installation convenience. Furthermore, the pump exhibits exceptional robustness, with strong tolerance to external interference such as moisture and foreign matter. It operates unaffected by environmental factors, ensuring stable operation and providing reliable support for fuel tank leak diagnosis.

[0268] While the above disclosure discusses some currently considered useful embodiments of the invention through various examples, it should be understood that, in order to facilitate understanding of the scope of the claims, this specification assigns numbers corresponding to the components shown in the embodiments to the components shown in the "Claims" and "Summary of the Invention" sections. However, this does not necessarily mean that the components shown in the claims are specifically components of the embodiments. In particular, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiments, unless otherwise specified, are not intended to limit the scope of the invention to these dimensions and are merely illustrative examples.

[0269] However, the dimensions or positional relationships of the components shown in the drawings are sometimes exaggerated for the purpose of clarifying the description. Furthermore, in the following description, for components that are identical or homogeneous, the same name or symbol will be used, and its detailed description will be omitted as appropriate. Furthermore, the various elements constituting the present invention may be a form in which the same component constitutes multiple elements so that one component serves as multiple elements. Conversely, the elements may be realized by multiple components sharing the function of one component. In addition, the contents described in some embodiments and implementation methods may also be utilized in other embodiments, implementation methods, etc. In addition, in this specification, "on" is not limited to the case where it is formed in contact with the upper surface, but also includes the case where it is formed separately above, and is also used to include the meaning of the presence of an intervening layer between layers.

[0270] Similarly, it should be noted that, in order to simplify the presentation of the present disclosure and facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of the invention sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not imply that the subject matter of the invention requires more features than those recited in the claims. In practice, an embodiment may have fewer features than the totality of the features of a single embodiment disclosed above.

[0271] As used in this application and the claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not intended to refer to the singular but may include the plural. Generally speaking, the terms "comprises" and "include" only indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list. A method or apparatus may also include other steps or elements.

[0272] In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0273] Although the present invention has been described with reference to the current specific embodiments, those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention, and that various equivalent changes or substitutions may be made without departing from the spirit of the present invention. Therefore, any changes or modifications to the above embodiments within the spirit of the present invention shall fall within the scope of the claims of this application.

Claims

1. A leakage diagnosis module, characterized in that: The device comprises at least a supporting shell (1), an air pump (2), a solenoid valve (3), a pressure sensor assembly (4) and an upper cover plate (5): The support housing (1) is provided with a pressure chamber (12) and a solenoid valve chamber (11) therein, and the pressure chamber (12) and the solenoid valve chamber (11) are communicated with each other through an air flow channel (140); The support housing (1) is provided with a diagnostic interface (111) for connecting to the device to be diagnosed and an atmospheric interface for connecting to the outside atmosphere; The solenoid valve chamber (11) is connected to the device to be diagnosed via a diagnostic interface (111); The air pump (2) is installed in the pressure chamber (12) inside the support shell (1), and extracts gas from the outside atmosphere through the atmospheric interface and pumps gas into the pressure chamber (12) or extracts gas in the pressure chamber (12) into the outside atmosphere; The solenoid valve (3) is installed in the solenoid valve chamber (11) inside the supporting shell (1) and is used to control the on / off of the air path between the device to be diagnosed and the pressure chamber (12); The pressure sensor assembly (4) is installed in the pressure chamber (12) inside the support shell (1) and is used to collect the pressure signal inside the pressure chamber (12); The upper cover plate (5) is fixedly connected to the supporting shell (1) through sealing.

2. The leak diagnosis module according to claim 1, characterized in that: The pressure sensor assembly (4) comprises a pressure sensor (41) and a circuit board. The pressure sensor (41) is soldered on the circuit board through surface mounting technology and forms an electrical connection with an electrical circuit on the circuit board.

3. The leak diagnosis module according to claim 1, characterized in that: The air pump (2) is a piezoelectric ceramic pump.

4. The leak diagnosis module according to claim 3, characterized in that: The pressure sensor assembly (4) is also provided with electronic components for driving the air pump, which are electrically connected to the PIN needle structure of the air pump (2) and are used to drive the air pump (2) to work.

5. The leakage diagnosis module according to any one of claims 1 to 4, characterized in that: An air pump housing fluid interface (121) communicating with an atmospheric interface is provided on the side wall of the pressure chamber (12); The air inlet end of the air pump (2) is connected to the air pump housing fluid interface (121), and the air outlet end of the air pump (2) is communicated with the pressure chamber (12), for extracting gas from the external atmosphere and pumping gas into the pressure chamber (12); or The air outlet of the air pump (2) is connected to the fluid interface (121) of the air pump housing, and the air inlet of the air pump (2) is communicated with the pressure chamber (12) for pumping the gas in the pressure chamber (12) into the external atmosphere.

6. The leak diagnosis module according to claim 5, characterized in that: When the solenoid valve (3) is in an open state, the air path between the device to be diagnosed and the air flow channel (140) is in communication; When the air pump (2) extracts gas from the outside atmosphere and pumps it into the pressure chamber (12): The external gas passes through the fluid interface (121) of the air pump housing, the air pump (2), the pressure chamber (12), the air flow channel (140), the solenoid valve chamber (11), and the diagnostic interface (111) to the device to be diagnosed, forming a diagnostic loop; When the air pump (2) pumps the gas in the pressure chamber (12) into the outside atmosphere, the gas flow path of the diagnostic circuit is opposite to that when the gas is pumped from the outside atmosphere into the pressure chamber (12).

7. The leak diagnostic module according to claim 6, characterized in that: The support housing (1) is further provided with a reference hole (113) and a solenoid valve housing fluid interface (114) on the side of the solenoid valve chamber (11); the reference hole (113) is used to connect the air flow channel (140) and the solenoid valve chamber (11); and the solenoid valve housing fluid interface (114) is connected to the atmosphere interface.

8. The leak diagnostic module according to claim 7, characterized in that: The solenoid valve (3) is in a closed state, the air path between the external device to be diagnosed and the air flow channel (140) is cut off, and the air path between the solenoid valve housing fluid interface (114) and the reference hole (113) is connected; When the air pump (2) extracts gas from the outside atmosphere and pumps it into the pressure chamber (12): External gas passes through the air pump housing fluid interface (121), the air pump (2), the pressure chamber (12), the air flow channel (140), the reference hole (113), the solenoid valve chamber (11), and returns to the external atmosphere through the solenoid valve housing fluid interface (114), forming a reference loop; The gas flow path of the reference circuit when the air pump (2) pumps the gas in the pressure chamber (12) to the outside atmosphere is opposite to that when the air is extracted from the outside atmosphere and pumped into the pressure chamber (12).

9. The leak diagnostic module according to claim 7, characterized in that: The air pump housing fluid interface (121) and the solenoid valve housing fluid interface (114) are arranged on the same side of the support housing (1) and are in communication with the atmosphere interface.

10. The leak diagnostic module according to claim 1, characterized in that: The air flow channel (140) is formed integrally with the support shell, and one end of the air flow channel (140) is an open end; The open end is provided with a plug (115): The plug (115) is in sealing cooperation with the air flow channel (140) to close the open end.

11. The leak diagnostic module according to claim 1, characterized in that: The support shell is provided with a first welding rib, and the upper cover plate (5) is provided with a second welding rib at a corresponding position; The first welding rib and the second welding rib are connected by welding to form a pressure chamber and a solenoid valve chamber structure.

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