A hydrogen fuel cell stack air tightness batch detection device

Abstract

The present invention relates to the field of hydrogen fuel cell detection technology, and specifically to a batch detection device for the air tightness of hydrogen fuel cell stacks. It includes a conveying mechanism and a detection mechanism, wherein the conveying mechanism has multiple bearing positions, each bearing position is provided with a lower carrier capable of simultaneously accommodating multiple batteries, and the detection mechanism includes an upper carrier and a pressure-maintaining component. When the upper carrier and the lower carrier are closed, a sealed cavity for individually accommodating each battery and an airway connecting the gas ports of adjacent batteries are formed between the two. A charging structure is also provided on the upper carrier, and the charging structure has a vent sleeve and a closed sleeve. Both the vent sleeve and the closed sleeve are provided with a linkage member that cooperates with the pressure-maintaining component. The present invention forms a sealed cavity for accommodating multiple batteries by closing the upper carrier and the lower carrier, and through the coordinated action of the pressure-maintaining component and the linkage member, the vent sleeve and the closed sleeve are sealed and docked with the corresponding battery gas ports, thereby improving the detection accuracy and efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel cell detection, and in particular to a batch detection device for hydrogen fuel cell stack air tightness. Background Art

[0002] In the production and testing process of hydrogen fuel cell stacks, air tightness testing is a key link to ensure their safety and performance. At present, traditional air tightness testing devices mostly use a single battery test method, by placing the battery in a sealed cavity, inflating and pressurizing it, and then monitoring the pressure change to determine whether there is a leak. Since the battery has an air inlet and an air outlet, it is generally inflated through the air inlet, and the air outlet is closed, so that the battery is pressurized to a predetermined value before it is tested for leaks. However, this method has the following problems: first, the detection efficiency is low, and it is difficult to adapt to large-scale, continuous production requirements. Second, the operation is complicated, and a single stack needs to be clamped and inflated each time, which increases manual intervention and the probability of error.

[0003] The currently disclosed Chinese patent authorization announcement number CN115588761B is a hydrogen fuel cell stack defect detection device and detection method, which includes a transport component, the transport component includes a conveyor belt driven by a drive roller, the conveyor belt is provided with a plurality of linearly distributed groups of spaced positioning holes, and a support tray is clamped in the positioning holes; a fuel cell, the lower end of the fuel cell is mounted on the support tray, the upper end of the fuel cell is provided with interface components on both sides, and the upper end of the fuel cell is provided with a connection terminal; a lifting component, the lifting component is fixedly installed in the middle of the circulating conveyor belt In the inner cavity, the lifting assembly includes a telescopic column, a top plate is provided at the end of the telescopic column, and the upper end of the top plate is opposite to the supporting tray; the detection assembly is installed at the upper end of the conveyor belt, the detection assembly includes a detection box and a sealing end cover, the lower end port of the detection box is opposite to the top plate, the upper end of the detection box is sealed and connected with the sealing end cover, and a sealing connection assembly is installed in the inner cavity of the detection box for transverse telescopic installation, and the upper end of the sealing end cover is symmetrically provided with an air intake pump and an exhaust pump, and the air intake pump and the exhaust pump are sealed and connected to the interface assembly through the sealing connection assembly, and the upper end of the sealing end cover is plugged with a pressure gauge for detecting the air pressure in the inner cavity.

[0004] According to the above patent, the patent forms a sealed environment by setting up a lifting drive and a sealing detection box, and the fuel cell is operated by air intake. The internal pressure is detected to detect whether the fuel cell is leaking. In conjunction with the drive of the conveyor belt, a loading, detection and unloading station switch is formed to achieve automated detection. However, when the sealing detection box is formed, the sealing end cover and the detection box may be poorly sealed due to insufficient pressure, which can easily lead to misjudgment of the airtightness detection. In addition, the one-to-one detection mode is not efficient and takes a lot of time for batch detection. Therefore, there is a need for an airtightness batch detection device that can provide a sealed environment for a hydrogen fuel cell stack, ensure the stability of the sealing environment, and detect multiple hydrogen fuel cell stacks at the same time. Summary of the Invention

[0005] In response to the problems existing in the prior art, a batch airtightness detection device for hydrogen fuel cell stacks is provided. A sealed cavity for accommodating multiple batteries is formed by closing the upper carrier and the lower carrier, and the synergistic effect of the pressure-maintaining component and the linkage part enables the vent sleeve and the closing sleeve to be sealed and docked with the battery gas port during the downward pressure of the upper carrier, and the valve stem structure is activated to cut off the airway connection after the battery charging is completed, so that multiple batteries enter an independent sealed state and perform airtightness detection synchronously, thereby improving the detection accuracy and efficiency.

[0006] In order to solve the problems of the prior art, the present invention provides a batch detection device for the air tightness of hydrogen fuel cell stacks, including a conveying mechanism and a detection mechanism, wherein the conveying mechanism has multiple bearing positions, each bearing position is provided with a lower carrier that can accommodate multiple batteries at the same time, and the detection mechanism includes an upper carrier that can be fitted with the lower carrier and a pressure-maintaining component connected to the upper carrier, and the lower carrier and the upper carrier both have sealing surfaces that can fit tightly with each other. When the upper carrier and the lower carrier are closed, a sealed cavity for each battery to be individually accommodated and not connected to each other and an air duct connecting the gas ports of adjacent batteries are formed between the two. The cells are all provided with a leakage detection structure, and the upper carrier is also provided with a charging structure capable of ventilating all the batteries, the charging structure having a vent tube sleeve and a closed tube sleeve, the vent tube sleeve and the closed tube sleeve being respectively connected to the air ports of the two outermost batteries among the multiple batteries, the vent tube sleeve and the closed tube sleeve are both provided with a linkage part cooperating with the pressure maintaining component, when the pressure maintaining component drives the upper carrier to fit and continuously apply pressure to the lower carrier, the vent tube sleeve and the closed tube sleeve are gradually driven by the linkage part to approach the battery and are sealed and connected to the air ports of the corresponding batteries, so that all the batteries form a continuous gas flow path during the unified charging process.

[0007] Preferably, both ends of the upper carrier are provided with extension rods extending horizontally outward, and each extension rod is slidably provided with a slider fixedly connected to the corresponding ventilation tube sleeve and the closed tube sleeve, and the slider is cooperated with the pressure maintaining assembly with the linkage part. When the lower carrier moves to the inspection station, the ventilation tube sleeve and the closed tube sleeve are respectively in a coaxial state with the corresponding battery gas port.

[0008] Preferably, the linkage has a pressure-receiving part arranged on the slider and a pressure-applying part arranged on the pressure-maintaining assembly. When the pressure-applying part acts on the pressure-receiving part following the downward pressing action of the pressure-maintaining assembly, the upper carrier is in a relatively static state. At this time, the slider gradually approaches the upper carrier under the drive of the pressure-receiving part.

[0009] Preferably, a return spring is provided between the slider and the extension rod. When the slider gradually approaches the upper carrier, the return spring is in a compressed state. When the pressure-applying part is separated from the pressure-receiving part, the return spring drives the slider to a reset state, so that the ventilation tube sleeve and the closing tube sleeve are disconnected from the corresponding battery gas port.

[0010] Preferably, the pressure-bearing part is a block structure, and the pressure-applying part is a rod structure. The pressure-bearing part has a slope extending outward from top to bottom. When the pressure-applying part applies vertical pressure to the pressure-bearing part along the slope, the slider is gradually subjected to an inward horizontal thrust along the extension rod.

[0011] Preferably, the pressure maintaining assembly includes a pressure plate and a hydraulic rod for driving the pressure plate to move. The upper carrier is provided with a plurality of guide rods passing vertically through the pressure plate. The pressure plate can move relative to the upper carrier along the guide rods. A buffer spring is also provided between the pressure plate and the upper carrier. When the pressure plate drives the upper carrier to fit and continuously apply pressure to the lower carrier, the buffer spring is in a compressed state.

[0012] Preferably, an anti-slip portion is provided at the upper end of each guide rod. When the pressure plate contacts the anti-slip portion, the buffer spring is in a normal state, and the pressure-applying portion and the pressure-receiving portion are in a state of being away from each other.

[0013] Preferably, a valve stem structure is provided on the upper carrier at a position corresponding to the formation of the air channel. When all batteries are fully charged, the air channel is in a closed state driven by the valve stem structure, so that the gas flow path between adjacent batteries is cut off, forming an independent charging and pressure detection state.

[0014] Preferably, the air leakage detection structure has a pressure sensor and a pressure conductor, and a compression spring is provided between the pressure conductor and the pressure sensor. When the pressure in the sealed cavity increases due to battery pressure release, the compression spring is in a compressed state under the compressive force of the pressure conductor.

[0015] Preferably, the pressure transmitter has a plate body movably arranged on the upper carrier and an airbag fixedly arranged on the upper carrier, the airbag is located below the plate body, and the plate body has a guide shaft that resists the compression spring. When the pressure in the sealed cavity increases and causes the airbag to expand, the plate body is in a lifted state under the pressure of the airbag.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. This invention utilizes a pressure-maintaining assembly and linkage to ensure that the vent sleeve and sealing sleeve simultaneously converge toward the battery gas port during the downward pressure of the pressure-maintaining assembly, achieving precise alignment and a sealed connection with the battery gas port. This ensures the stability and tightness of the gas flow path during the uniform charging process, avoids leakage caused by misaligned connections or poor sealing, and improves detection accuracy and efficiency.

[0018] By simultaneously placing multiple batteries on a lower carrier and attaching them to each other, multiple independent, non-interfering sealed cavities are formed, allowing each battery to undergo airtightness testing under the same conditions. Once all batteries are synchronously charged to the target pressure, the leak detection structure independently monitors the pressure changes within each sealed cavity, accurately identifying leaking battery cells without interfering with each other. This ensures accurate test results and avoids the inefficiencies associated with individual testing.

[0019] 2. This invention utilizes the compressive force of the slider and the pressure-applying force of the pressure plate, utilizing the slope of the compressive force to convert vertical pressure into horizontal thrust, achieving automatic and synchronous connection of the vent sleeve and the sealing sleeve to the battery vent. As the slider overcomes the resistance of the return spring and slides along the extension rod during the push process, the connection is stable and precise, preventing seal failure due to misalignment.

[0020] At the same time, after the pressure plate releases pressure on the upper carrier, the pressure-applying portion separates from the pressure-receiving portion, and the return spring releases its elastic potential energy, causing the vent sleeve and the sealing sleeve to quickly reset and automatically separate. This not only improves the reliability of the gas port connection and the stability of the pressurization process, but also automates the testing process, improving test efficiency and repeatability. It is suitable for efficient airtightness testing of batch hydrogen fuel cell stacks.

[0021] 3. The present invention uses a buffer spring to enable the upper carrier to obtain uniform and stable contact pressure when it descends to fit the lower carrier, effectively preventing the sealing failure of the sealed cavity due to impact or pressure fluctuation, and ensuring the stability of the sealing environment during the detection process.

[0022] On this basis, the airway is isolated and controlled through the valve stem structure, so that each battery enters an independent sealed state after charging without interfering with each other, thereby achieving individual and accurate airtightness testing of each battery, significantly improving the accuracy and reliability of the test results, and is suitable for efficient and automated testing of batch hydrogen fuel cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the three-dimensional structure of a batch detection device for air tightness of hydrogen fuel cell stacks of the present invention.

[0024] Figure 2 It is a schematic diagram of the three-dimensional structure of the hydrogen fuel cell stack of the present invention.

[0025] Figure 3 It is a schematic diagram of the three-dimensional structure of the lower carrier and battery of a hydrogen fuel cell stack airtightness batch detection device of the present invention.

[0026] Figure 4 It is a three-dimensional structural schematic diagram of a lower carrier, an upper carrier and a pressure-maintaining component of a hydrogen fuel cell stack airtightness batch detection device of the present invention.

[0027] Figure 5 It is a planar cross-sectional view of a lower carrier, an upper carrier and a pressure-maintaining component of a hydrogen fuel cell stack airtightness batch detection device of the present invention.

[0028] Figure 6 It is a three-dimensional structural cross-sectional view of a lower carrier, an upper carrier and a pressure-maintaining component of a hydrogen fuel cell stack airtightness batch detection device of the present invention.

[0029] Figure 7 It is a planar cross-sectional view of an upper carrier, a lower carrier and a gas leakage detection structure of a batch gas tightness detection device for a hydrogen fuel cell stack of the present invention.

[0030] Figure 8 It is a three-dimensional structural cross-sectional view of an upper carrier, a lower carrier and a leakage detection structure of a hydrogen fuel cell stack airtightness batch detection device of the present invention.

[0031] Figure 9 It is a schematic diagram of the state of a closed tube sleeve connected to the battery gas port of a hydrogen fuel cell stack air tightness batch detection device of the present invention.

[0032] Figure 10 It is a schematic diagram of the state in which the vent sleeve of a hydrogen fuel cell stack air tightness batch detection device of the present invention is connected to the battery gas port.

[0033] Figure 11 The present invention Figure 5 A magnified schematic diagram of .

[0034] The numbers in the figure are: 1. Conveying mechanism; 2. Detection mechanism; 3. Battery; 31. Air port; 4. Lower carrier; 41. Sealed cavity; 42. Airway; 421. Valve stem structure; 5. Upper carrier; 51. Extension rod; 52. Slider; 521. Return spring; 6. Pressure maintaining assembly; 61. Pressure plate; 611. Guide rod; 6111. Anti-slip part; 612. Buffer spring; 62. Hydraulic rod; 7. Leakage detection structure; 71. Pressure sensor; 711. Compression spring; 72. Pressure transmission part; 721. Plate; 7211. Guide shaft; 722. Airbag; 8. Pressurization structure; 81. Ventilation sleeve; 82. Closing sleeve; 83. Linkage; 831. Pressure-bearing part; 832. Pressure-applying part. DETAILED DESCRIPTION

[0035] In order to further understand the features, technical means, specific objectives and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] See also Figures 1-6 and Figure 11 As shown, a hydrogen fuel cell stack airtightness batch detection device includes a conveying mechanism 1 and a detection mechanism 2, the conveying mechanism 1 has multiple bearing positions, each bearing position is provided with a lower carrier 4 that can accommodate multiple batteries 3 at the same time, the detection mechanism 2 includes an upper carrier 5 that can be fitted with the lower carrier 4 and a pressure-maintaining component 6 connected to the upper carrier 5, the lower carrier 4 and the upper carrier 5 both have sealing surfaces that can fit tightly together, when the upper carrier 5 and the lower carrier 4 are closed, a sealed cavity 41 for each battery 3 to be individually accommodated and not connected to each other and an air duct 42 connecting the air ports 31 of adjacent batteries 3 are formed therebetween, and a leakage detection structure 7 is provided on the upper carrier 5 corresponding to each battery 3. The carrier 5 is also provided with a charging structure 8 that can ventilate all batteries 3. The charging structure 8 has a vent sleeve 81 and a closed sleeve 82. The vent sleeve 81 and the closed sleeve 82 can be respectively connected to the air ports 31 of the two outermost batteries 3 among the multiple batteries 3. The vent sleeve 81 and the closed sleeve 82 are both provided with a linkage 83 that cooperates with the pressure maintaining component 6. When the pressure maintaining component 6 drives the upper carrier 5 to fit with the lower carrier 4 and continuously applies pressure, the vent sleeve 81 and the closed sleeve 82 are gradually driven by the linkage 83 to approach the battery 3 and are sealed and connected to the air ports 31 of the corresponding batteries 3, so that all batteries 3 form a continuous gas flow path during the unified charging process.

[0037] The battery 3 has an air inlet 31 for air intake and an air outlet 31 for air exhaust.

[0038] The ends of the lower carrier 4 and the upper carrier 5 that contact each other are both provided with a sealing layer, and the surface where the two sealing layers contact each other is the sealing surface. The sealing layer is not shown in the figure. The sealing layer is made of an elastic sealing material, such as a sealing ring or a rubber gasket.

[0039] When the lower carrier 4 and the upper carrier 5 are closed, the sealing surfaces therebetween fit tightly together to form the reliably sealed sealing cavity 41 and the air channel 42 to fill any small gaps that may exist and produce elastic deformation when under pressure, further enhancing the sealing effect.

[0040] When conducting batch testing for the airtightness of hydrogen fuel cell stacks (3), the cells 3 to be tested are first placed sequentially onto the lower carrier 4 in the loading position of the conveyor mechanism 1. Each lower carrier 4 can accommodate multiple cells 3 simultaneously, ensuring appropriate spacing between cells 3 for subsequent sealing and testing operations. Once all cells 3 are correctly placed, the conveyor mechanism 1 transports the lower carrier 4 to the working position of the testing mechanism 2. At this point, the upper carrier 5 of the testing mechanism 2 is in an open state, maintaining a certain distance from the lower carrier 4, ready for the next closing operation.

[0041] Subsequently, the pressure-maintaining assembly 6 begins to work, driving the upper carrier 5 to move downward, so that it fits and contacts the lower carrier 4. During this process, the air leakage detection structure 7 on the upper carrier 5 is aligned with the corresponding position of each battery 3, while the vent sleeve 81 and the closed sleeve 82 are respectively aligned with the air ports 31 of the two outermost batteries 3. As the pressure-maintaining assembly 6 continues to press downward, it not only maintains pressure on the upper carrier 5, making the fit between the upper carrier 5 and the lower carrier 4 tighter, but also prompts the linkage 83 to drive the vent sleeve 81 and the closed sleeve 82 to gradually approach the air ports 31 of the corresponding batteries 3, and finally achieve a sealed connection to ensure that gas does not leak from the connection.

[0042] When the upper carrier 5 and the lower carrier 4 are fully bonded, multiple independent, unconnected sealed cavities 41 are formed between them, each of which precisely accommodates a single battery 3. Simultaneously, the air channels 42 formed after the upper carrier 5 and the lower carrier 4 are bonded connect the gas ports 31 between adjacent batteries 3, thereby establishing a continuous gas flow path during the charging process. The gas flow path originates from the vent sleeve 81 in the charging structure 8, passes through the gas port 31 of the connected battery 3, the air channel 42, the gas ports 31 of other batteries 3, and finally connects to the end of the closed sleeve 82, forming a complete gas passage.

[0043] Next, the pressure charging phase begins. The vent sleeve 81 is connected to the air pump and compressed gas begins to be injected into the battery 3. The gas enters the air inlet 31 of the first battery 3 through the vent sleeve 81, then passes through the air passages 42 between each battery 3, and finally reaches the sealing sleeve 82. As the gas is continuously injected, the pressure inside all batteries 3 gradually rises to the set value. Once the target pressure is reached, the pressure charging stops and the pressure maintenance phase begins.

[0044] During the pressure maintenance stage, the battery 3 will maintain a constant pressure for a period of time in order to fully expose possible tiny leaks. During this period, the leakage detection structure 7 monitors the pressure changes in the sealed cavity 41 around each battery 3 in real time. If a battery 3 leaks, the pressure in the sealed cavity 41 will fluctuate abnormally due to gas infiltration. Since the pressure inside the battery 3 is much higher than the pressure in the sealed cavity 41, the resulting pressure difference will form a pressure gradient at the leak point. Gas always tends to flow from high-pressure areas to low-pressure areas, and is then captured by the corresponding leakage detection structure 7. Accurately identify tiny pressure changes and transmit data to the control system for analysis and judgment.

[0045] If no pressure anomalies are detected during the test, all batteries 3 are leak-free and meet airtightness standards. Conversely, if a pressure drop or other abnormal signal is detected at a specific point, the corresponding battery 3 has an airtightness issue and needs to be removed from the batch for further inspection and repair. The control system automatically determines the test results for each battery 3 based on the feedback data and generates a corresponding test report for the operator to review and process.

[0046] After testing is complete, the pressure-maintaining assembly 6 releases pressure, driving the upper carrier 5 upward and out of contact with the lower carrier 4. At this point, the vent sleeve 81 and the sealing sleeve 82, driven by the linkage 83, also separate from the gas port 31 of the battery 3, returning to their initial positions. Finally, the conveyor mechanism 1 transports the lower carrier 4 and the battery 3 on it away from the testing station and continues testing subsequent batteries 3.

[0047] See also Figure 4-10 As shown, both ends of the upper carrier 5 are provided with extension rods 51 extending horizontally outward, and each extension rod 51 is slidably provided with a slider 52 fixedly connected to the corresponding ventilation sleeve 81 and the closed sleeve 82, and the slider 52 and the pressure maintaining assembly 6 are cooperated with the linkage 83. When the lower carrier 4 moves to the inspection station, the ventilation sleeve 81 and the closed sleeve 82 are respectively in a coaxial state with the corresponding battery 3 gas port 31.

[0048] After the lower carrier 4 moves to the inspection station, the vent sleeve 81 and the sealing sleeve 82 are initially coaxially aligned with the corresponding gas port 31 of the battery 3. At this point, the sliders 52 on the extension rods 51 at both ends of the upper carrier 5 are in their initial sliding positions. When the pressure-maintaining assembly 6 does not further operate on the upper carrier 5, the linkage 83 remains relaxed, meaning that the slider 52 is not subjected to any thrust from the linkage 83.

[0049] When the pressure-maintaining assembly 6 is activated and continuously applies pressure to the upper carrier 5, the movement of the pressure-maintaining assembly 6 is converted into a thrust force on the slider 52 along the extension rod 51 through the linkage 83. The slider 52 slides along the extension rod 51 toward the gas port 31 of the battery 3, thereby driving the vent sleeve 81 and the sealing sleeve 82 to simultaneously advance toward the gas port 31 of the battery 3.

[0050] Until the vent sleeve 81 and the sealing sleeve 82 are respectively tightly fitted at the corresponding gas port 31 of the battery 3. The linkage 83 ensures that the vent sleeve 81 and the sealing sleeve 82 can achieve precise and stable horizontal movement while moving with the pressure maintaining assembly 6, thereby ensuring a reliable and non-deflective sealing connection between the vent sleeve 81 and the sealing sleeve 82 and the gas port 31 of the battery 3, ensuring that all batteries 3 are uniformly charged without leakage at the gas port 31 connection.

[0051] See also Figure 4-Figure 6 、 Figure 9 and Figure 10 As shown, the linkage member 83 has a pressure-receiving portion 831 arranged on the slider 52 and a pressure-applying portion 832 arranged on the pressure-maintaining component 6. When the pressure-applying portion 832 acts on the pressure-receiving portion 831 following the downward pressing action of the pressure-maintaining component 6, the upper carrier 5 is in a relatively static state. At this time, the slider 52 gradually approaches the upper carrier 5 under the drive of the pressure-receiving portion 831.

[0052] When the pressure-maintaining assembly 6 starts to press downward, the pressure-applying portion 832 thereon moves downward therewith, contacts and applies pressure to the pressure-receiving portion 831 on the slider 52. At this time, the upper carrier 5 and the lower carrier 4 remain in contact and are in a relatively static state.

[0053] As the pressure-applying portion 832 continues to press downward on the pressure-receiving portion 831, the slider 52, pushed by the pressure-receiving portion 831, moves along the extension rod 51 toward the upper carrier 5, i.e., slides toward the gas port 31 of the battery 3. This causes the vent sleeve 81 and the sealing sleeve 82 connected to each slider 52 to simultaneously advance toward the corresponding gas port 31, gradually approaching and ultimately abutting against the gas port 31 of the battery 3, completing the docking of the gas port 31 and ensuring stability during the subsequent charging process.

[0054] See also Figure 4-Figure 6 、 Figure 9 and Figure 10As shown, a return spring 521 is provided between the slider 52 and the extension rod 51. When the slider 52 gradually approaches the upper carrier 5, the return spring 521 is in a compressed state. When the pressure-applying portion 832 is separated from the pressure-receiving portion 831, the return spring 521 drives the slider 52 to a reset state, so that the vent sleeve 81 and the sealing sleeve 82 are disconnected from the corresponding gas port 31 of the battery 3.

[0055] When the pressure-applying portion 832 acts downward on the pressure-receiving portion 831 and pushes the slider 52 to move along the extension rod 51 toward the upper carrier 5, the slider 52 overcomes the elastic force of the return spring 521 and is compressed. At this time, the ventilation sleeve 81 and the closing sleeve 82 are pushed forward and establish a connection with the gas port 31 of the battery 3.

[0056] When the pressure-maintaining assembly 6 completes its downward movement and begins its return stroke, the pressure-applying portion 832 moves upward and gradually disengages from the pressure-receiving portion 831. At this point, the external force acting on the slider 52 disappears, and the return spring 521 releases its previously stored elastic potential energy, pushing the slider 52 to slide back along the extension rod 51 and return to its initial position. Simultaneously, the slider 52 returns to its original position, simultaneously moving the vent sleeve 81 and the sealing sleeve 82 away from the battery 3's gas port 31, releasing the seal between them and preparing for the next charge of the battery 3.

[0057] See also Figure 4-Figure 6 、 Figure 9 and Figure 10 As shown, the pressure-bearing part 831 is specifically a block structure, and the pressure-applying part 832 is specifically a rod structure. The pressure-bearing part 831 has a slope extending outward from top to bottom. When the pressure-applying part 832 applies vertical pressure to the pressure-bearing part 831 along the slope, the slider 52 is gradually subjected to an inward horizontal thrust along the extension rod 51.

[0058] When the pressure-applying portion 832 contacts the slope of the pressure-receiving portion 831 , the vertical pressure is decomposed and transferred to the slope, and part of the pressure is converted into a horizontal force through the inclination angle of the slope, thereby applying an inward thrust to the slider 52 .

[0059] During this process, the slider 52 is acted upon by the horizontal thrust, overcomes the resistance of the return spring 521 , and slides along the extension rod 51 toward the upper carrier 5 , thereby pushing the vent sleeve 81 and the sealing sleeve 82 toward the gas port 31 of the battery 3 .

[0060] See also Figure 4-10As shown, the pressure maintaining assembly 6 includes a pressure plate 61 and a hydraulic rod 62 for driving the pressure plate 61 to move. A plurality of guide rods 611 are provided on the upper carrier 5, which pass through the pressure plate 61 vertically. The pressure plate 61 can move relative to the upper carrier 5 along the guide rods 611. A buffer spring 612 is also provided between the pressure plate 61 and the upper carrier 5. When the pressure plate 61 drives the upper carrier 5 to fit with the lower carrier 4 and continuously applies pressure, the buffer spring 612 is in a compressed state.

[0061] When the pressing plate 61 pushes the upper carrier 5 to fit the lower carrier 4 and continues to apply pressure, the buffer spring 612 between the pressing plate 61 and the upper carrier 5 begins to be compressed, absorbing excess impact force and maintaining a stable contact pressure.

[0062] The compression of the buffer spring 612 ensures a uniform and continuous sealing fit between the upper carrier 5 and the lower carrier 4, preventing loose connection or sealing failure due to pressure fluctuations, and providing a stable and reliable pressure-maintaining environment for the detection process.

[0063] See also Figure 4-10 As shown, each guide rod 611 has an anti-slip portion 6111 at its upper end. When the pressure plate 61 contacts the anti-slip portion 6111, the buffer spring 612 is in a normal state, and the pressure-applying portion 832 and the pressure-receiving portion 831 are in a state of being separated from each other.

[0064] When the pressure plate 61 moves upward under the drive of the hydraulic rod 62 and contacts the anti-slip portion 6111, it indicates that the pressure plate 61 has reached the set upper limit position. At this time, the buffer spring 612 is not compressed and is in a normal state of natural extension. At this time, as the pressure plate 61 continues to be lifted upward, it drives the upper carrier 5 away from the lower carrier 4.

[0065] At the same time, the pressure-applying portion 832 and the pressure-receiving portion 831 are in a state of being separated from each other, that is, the linkage member 83 is not in effect, the slider 52 is in the initial position, the vent sleeve 81 and the sealing sleeve 82 are not in contact with the gas port 31 of the battery 3, and are now in a ready state waiting for the start of detection.

[0066] See also Figure 5 、 Figure 6 and Figure 11 As shown, a valve stem structure 421 is provided on the upper carrier 5 at a position corresponding to the formation of the air channel 42. When all batteries 3 have completed charging, the air channel 42 is in a closed state under the drive of the valve stem structure 421, so that the gas flow path between adjacent batteries 3 is cut off, forming an independent charging detection state.

[0067] The specific driver of the valve stem structure 421 is not shown in the figure.

[0068] When all batteries 3 are uniformly charged, the valve stem structure 421 is driven to move, inserting into the air passage 42 and sealing it. At this point, the previously connected gas flow path is severed, and the air passages 42 between each battery 3 are isolated from each other, leaving each battery 3 in an independently sealed state. This ensures that during subsequent testing, if a leak in a battery 3 occurs, it will only affect the pressure change of that battery, without affecting the test results of other batteries 3, thereby enabling accurate airtightness testing of each battery 3.

[0069] See also Figure 5-10 As shown, the air leakage detection structure 7 has a pressure sensor 71 and a pressure conductor 72, and a compression spring 711 is provided between the pressure conductor 72 and the pressure sensor 71. When the pressure in the sealed cavity 41 increases due to the pressure release of the battery 3, the compression spring 711 is in a compressed state under the pressure of the pressure conductor 72.

[0070] When a battery 3 leaks, gas seeps from within the battery 3 into the sealed cavity 41. Over time, the accumulation of leaked gas causes the pressure within the sealed cavity 41 to gradually increase, acting on the pressure transmitter 72. At this point, the pressure transmitter 72, driven by the gas pressure, moves toward the pressure sensor 71, compressing the compression spring 711 between the two, causing the compression spring 711 to enter a compressed state.

[0071] The compression spring 711 absorbs part of the impact force by deformation, and transmits the pressure change to the pressure sensor 71 in a stable mechanical form. The sensor converts the pressure signal into an electrical signal for analysis, thereby achieving accurate detection of the air tightness of the battery 3.

[0072] See also Figure 5-10 As shown, the pressure transmission member 72 has a plate body 721 movably arranged on the upper carrier 5 and an airbag 722 fixedly arranged on the upper carrier 5, the airbag 722 is located below the plate body 721, and the plate body 721 has a guide shaft 7211 that resists the compression spring 711. When the pressure in the sealed cavity 41 increases and causes the airbag 722 to expand, the plate body 721 is in a lifted state under the pressure of the airbag 722.

[0073] When the pressure within sealed cavity 41 rises due to battery 3 leakage, the gas pressure inflates airbag 722, pushing plate 721 above it upward. The expanding force of airbag 722 lifts plate 721, driving guide shaft 7211 upward simultaneously. This force compresses compression spring 711, which then compresses it. Compression spring 711 transmits the pressure from plate 721 to pressure sensor 71 with a stable elastic force, enabling precise sensing of changes in leakage pressure.

[0074] The present invention utilizes the synergistic effect of the pressure-maintaining assembly 6 and the linkage 83 to automatically align and seal the vent sleeve 81 and the sealing sleeve 82 with the gas port 31 of the battery 3 during the downward pressure of the upper carrier 5, thereby improving the stability of the charging path and the reliability of the seal. During this process, the slope of the pressure-receiving portion 831 cooperates with the pressure-applying portion 832 to convert vertical pressure into horizontal thrust, synchronously driving the slider 52 to precisely move the vent sleeve 81 and the sealing sleeve 82. The return spring 521 automatically separates them after docking, ensuring the automation and repeatability of the testing process.

[0075] As the pressure plate 61 is pressed downward, the buffer spring 612 ensures uniform and stable pressure when the upper carrier 5 and the lower carrier 4 are in contact, preventing seal failure. The valve stem structure 421 cuts off the airway 42, allowing each battery 3 to enter an independent sealed state and achieve precise individual testing. While improving the efficiency of simultaneous testing of multiple batteries 3, it significantly enhances detection accuracy and stability, making it suitable for the large-scale, high-precision automated airtightness testing needs of hydrogen fuel cell 3 stacks.

[0076] The above embodiments merely represent one or more embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of protection of the present invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present invention, and such modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the appended claims.

Claims

1. A batch gas tightness testing device for hydrogen fuel cell stacks, comprising a conveying mechanism and a testing mechanism, wherein the conveying mechanism has multiple carrying positions, each of which is provided with a lower carrier capable of simultaneously accommodating multiple batteries; It is characterized by: The detection mechanism includes an upper carrier capable of being attached to a lower carrier and a pressure-maintaining assembly connected to the upper carrier. The lower carrier and the upper carrier both have sealing surfaces capable of being tightly attached to each other. When the upper carrier and the lower carrier are closed, a sealed cavity for individually accommodating each battery and not communicating with each other is formed therebetween, as well as an air channel connecting the air ports of adjacent batteries. The upper carrier is provided with a leakage detection structure corresponding to each battery, and is also provided with a charging structure capable of ventilating all batteries. The charging structure comprises a venting sleeve and a sealing sleeve, which can be respectively connected to the air ports of the two outermost batteries among the multiple batteries. The venting sleeve and the sealing sleeve are both provided with a linkage member that cooperates with the pressure-maintaining assembly. When the pressure-maintaining assembly drives the upper carrier and the lower carrier to fit together and continuously apply pressure, the vent sleeve and the sealing sleeve, driven by the linkage, gradually approach the battery and are sealed to the gas ports of the corresponding battery, so that all batteries form a continuous gas flow path during the unified charging process; A valve stem structure is provided on the upper carrier at a position corresponding to the formation of the air channel; Both ends of the upper carrier are provided with extension rods extending horizontally outward, and a slider fixedly connected to the corresponding vent sleeve and the sealing sleeve is slidably provided on each extension rod. The slider and the pressure-maintaining assembly are equipped with the linkage member. When the lower carrier moves to the inspection station, the vent sleeve and the sealing sleeve are respectively coaxial with the corresponding battery gas port. The pressure-maintaining assembly includes a pressure plate and a hydraulic rod for driving the pressure plate to move. The upper carrier is provided with multiple guide rods that pass through the pressure plate vertically. The pressure plate can move relative to the upper carrier along the guide rods. A buffer spring is also provided between the pressure plate and the upper carrier. When the pressure plate drives the upper carrier to fit and continuously apply pressure to the lower carrier, the buffer spring is in a compressed state.

2. A hydrogen fuel cell stack airtightness batch detection device according to claim 1, characterized in that: The linkage part has a pressure-receiving part arranged on the slider and a pressure-applying part arranged on the pressure-maintaining assembly. When the pressure-applying part acts on the pressure-receiving part following the downward pressing action of the pressure-maintaining assembly, the upper carrier is in a relatively static state. At this time, the slider gradually approaches the upper carrier under the drive of the pressure-receiving part.

3. A hydrogen fuel cell stack airtightness batch detection device according to claim 2, characterized in that: A return spring is provided between the slider and the extension rod. When the slider gradually approaches the upper carrier, the return spring is in a compressed state. When the pressure-applying part is separated from the pressure-receiving part, the return spring drives the slider to a reset state, so that the vent sleeve and the closing sleeve are disconnected from the corresponding battery air port.

4. A hydrogen fuel cell stack airtightness batch detection device according to claim 3, characterized in that: The pressure-bearing part is specifically a block structure, and the pressure-applying part is specifically a rod structure. The pressure-bearing part has a slope extending outward from top to bottom. When the pressure-applying part applies vertical pressure to the pressure-bearing part along the slope, the slider is gradually subjected to an inward horizontal thrust along the extension rod.

5. The hydrogen fuel cell stack airtightness batch detection device according to claim 1, characterized in that: An anti-slip portion is provided at the upper end of each guide rod. When the pressure plate contacts the anti-slip portion, the buffer spring is in a normal state, and the pressure-applying portion and the pressure-receiving portion are in a state of being away from each other.

6. A hydrogen fuel cell stack airtightness batch detection device according to claim 1, characterized in that: The air leakage detection structure has a pressure sensor and a pressure conductor. A compression spring is provided between the pressure conductor and the pressure sensor. When the pressure in the sealed cavity increases due to battery pressure release, the compression spring is in a compressed state under the compressive force of the pressure conductor.

7. A hydrogen fuel cell stack airtightness batch detection device according to claim 6, characterized in that: The pressure transmission component has a plate body movably arranged on the upper carrier and an airbag fixedly arranged on the upper carrier. The airbag is located below the plate body. The plate body has a guide shaft that resists the compression spring. When the pressure in the sealed cavity increases and causes the airbag to expand, the plate body is in a lifted state under the pressure of the airbag.

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