Air tightness testing apparatus

Abstract

This invention discloses an airtightness testing device, including a drive mechanism and an air port connection assembly. The air port connection assembly includes at least one centering component; the centering component includes a base connected to the drive mechanism; a first slider that can slide axially within the accommodating space of the base; a first elastic element that axially connects the first slider and the base; a floating element including a sliding part and a sealing part with an elastic sealing head, the sealing part extending out of the base and having a through air passage inside; a second elastic element that axially connects the floating element and the base; the sliding part and the inner wall of the accommodating space form a first guide structure, the radial dimension of which gradually expands away from the sealing head, enabling the floating element to have both axial sliding and radial floating capabilities; the opposite end faces of the sliding part and the first slider form a second guide structure, which can decompose the axial force into a radial component, driving the floating element to adjust radially adaptively, ensuring that the elastic sealing head and the air port of the product under test are automatically coaxially sealed. This device can automatically complete centering and clamping, improving testing efficiency and reliability.

Description

Technical Field

[0001] This invention relates to the field of sealing testing, and more particularly to an airtightness testing device. Background Technology

[0002] With the continuous advancement of industrialization, the demand for automation is increasing. Factories often rely on diverse testing equipment to inspect products and ensure they meet manufacturing process standards. High-pressure gas tightness testing is particularly crucial in industrial automation. Currently, two main methods are commonly used: First, when high-pressure pipelines use standard threaded configurations, PTFE tape is directly wrapped around the threads or liquid PTFE tape is applied, and then the threads are tightened together to achieve a sealing connection. Second, high-pressure quick-connect fittings are used to connect pipelines. These fittings consist of male and female connectors; one end is fixed, and the other is movable. To connect, the movable end is inserted into the fixed end, and a click indicates connection. To disconnect, the locking ring must be manually pressed to unlock, and then the movable end is pulled out. While these high-pressure connection methods achieve basic functions, they are time-consuming and labor-intensive to operate, and inconvenient to disassemble, making them less efficient in today's industrial automation context. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, this invention provides an airtightness testing device that can automatically complete the centering and clamping operations, ensuring a sealed connection between the testing device and the air port of the product under test, thereby improving connection efficiency and testing reliability.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is: an airtightness testing device, comprising a driving mechanism and an air port connection assembly connected to the driving mechanism; the air port connection assembly includes at least one centering component, the centering component comprising:

[0005] The base is connected to the drive mechanism and has a accommodating space;

[0006] The first slider is slidably disposed within the accommodating space along the axial direction of the base;

[0007] A first elastic element is axially connected between the first slider and the base;

[0008] A floating component includes a sliding part and a sealing part. The sliding part is disposed in the accommodating space. The sealing part extends out of the base and has an elastic sealing head at one end opposite to the sliding part. An air passage is provided inside the sealing part, which passes through the elastic sealing head.

[0009] The second elastic element is axially connected between the floating element and the base;

[0010] The outer periphery of the sliding part and the inner wall of the accommodating space form a first guide structure. The radial dimension of the first guide structure expands in the direction away from the elastic sealing head to allow the floating part to slide axially and float radially along the base simultaneously. The opposite end face of the sliding part and the first slider forms a second guide structure. The second guide structure decomposes the axial force into a radial component through the geometry of the contact surface, so that the floating part can adaptively adjust radially to achieve coaxial sealing between the elastic sealing head and the air port of the product under test.

[0011] It should be noted that in this application, axial direction refers to the direction along the central axis of the base, i.e., the direction of movement of the air port connection assembly. Radial direction refers to the direction perpendicular to the axial direction. Radial plane refers to a plane perpendicular to the axial direction, used to describe the radial position adjustment or range of movement. The definitions of axial, radial, and radial plane in this application are based on the device's own structure and do not depend on the external installation posture. When the device is placed vertically, the axial direction is parallel to the vertical direction, the radial direction is parallel to the horizontal direction, and the radial plane is parallel to the horizontal plane. This description is only an exemplary scenario; in actual applications, the relative relationships of axial, radial, and radial plane are always based on the central axis of the base and are not limited by the installation direction.

[0012] The contact surface geometry of the second guide structure refers to the non-axial contour (such as a conical surface) of the contact surface, which causes the axial force to generate a normal component on the contact surface, and then decomposes it into a radial component that drives the floating component to adjust radially.

[0013] The airtightness testing device of this application achieves radial adaptive adjustment during the axial sliding of the floating part through the coordinated cooperation of the first guide structure and the second guide structure. The first guide structure releases the radial constraint through the cone surface gap, and the second guide structure achieves directional centering through mechanical decomposition. The combination of the two can quickly compensate for the positional and shape deviations (such as the bottom of the air port being a plane, slope, or sphere) between the elastic sealing head and the air port of the product under test, ensuring accurate centering and sealing.

[0014] Optionally, the second guide structure includes:

[0015] A first conical surface is disposed on the side of the first slider facing the sliding portion;

[0016] A second conical surface is disposed on the side of the sliding part facing the first slider, and the second conical surface cooperates with the first conical surface.

[0017] The second guide structure, which uses conical surfaces, can utilize the self-centering property of the conical surface to uniformly decompose the axial force into a radial component, enabling the floating component to achieve omnidirectional fine-tuning and centering, thus improving centering accuracy. Specifically, precise centering is achieved through the contact between the conical surfaces of the first slider and the sliding part, utilizing the self-centering property of the conical surface. When an axial force is applied to the two conical surfaces, their axisymmetric geometry automatically guides the floating component to move radially until the centerlines of the two conical surfaces coincide. During this process, the axial force is uniformly decomposed into a radial component along the normal direction of the conical surface, driving the floating component to perform omnidirectional fine-tuning in the radial plane, ensuring that the elastic sealing head and the air port are coaxial. Simultaneously, the second guide structure has a simple shape and is easy to manufacture. It should be noted that the first and second conical surfaces can be incomplete conical surfaces; through holes can be provided on the conical surfaces or only a portion of the conical segment can be cut off, but this does not affect the fit between them. The self-centering property refers to the ability of a conical surface to precisely align and maintain a consistent position around a common axis of rotation (centerline) by means of the unique axisymmetric geometry of the conical surface and the force applied axially.

[0018] Optionally, the first guide structure includes:

[0019] The first conical surface is disposed on the outer peripheral side of the sliding part;

[0020] The second conical surface is disposed on the inner wall of the accommodating space. The first and second conical surfaces are conical or pyramidal surfaces, and the second conical surface mates with the first conical surface.

[0021] The first guide structure with conical surface fit gradually expands its radial dimension, providing the floating part with a composite motion space of sliding along the axis and floating along the radial direction, thus meeting the centering adjustment requirements.

[0022] It should be noted that the first and second conical surfaces may not be complete conical surfaces. Through holes may be provided on the conical surfaces or only a portion of the conical segment may be cut off, but this does not affect the mating function between the two.

[0023] Optionally, the outer periphery of the first slider is a cylindrical or prismatic surface, and the inner wall of the accommodating space is provided with a matching cylindrical or prismatic surface. This cylindrical or prismatic surface fit restricts the first slider to slide only along the axial direction, preventing a decrease in guiding accuracy due to radial displacement. The cylindrical surface fit offers advantages such as easier machining and lower friction, making it more suitable for high-speed testing scenarios; while the prismatic surface fit provides stronger torsional strength through planar contact, making it more suitable for high-load testing requirements.

[0024] Optionally, the airtightness testing device further includes an adjustment component connected between the drive mechanism and the base. This adjustment component is used to adjust the initial position of the base in the radial plane. Specifically, the adjustment component can manually or electrically drive the base to move in the radial plane, achieving coarse adjustment of the centering component to adapt to the air port position requirements of different products under test.

[0025] Optionally, the base includes a changeover plate detachably connected to the adjustment assembly. The changeover plate and adjustment assembly can be quickly separated via a detachable connection method such as bolts or pins. During replacement, it is not necessary to disassemble each part of the air port connection assembly individually; simply removing the changeover plate from the adjustment assembly allows the entire air port connection assembly to be separated from the adjustment assembly. This modular design significantly shortens changeover time and substantially improves changeover efficiency.

[0026] Optionally, the air port connection assembly further includes a type-change identification sensor, which is disposed on the outer wall of the base and used to detect the matching status between the product under test and the air port connection assembly. Specifically, the type-change sensor can automatically verify the matching between the air port connection assembly and the product under test by recognizing the type-change plate marking information (such as barcodes or mechanical codes), and feed the signal back to the control system, thereby avoiding test failure or product damage caused by type-change errors. Further optionally, the type-change sensor can be placed close to the type-change plate to ensure stable identification signals and improve the automation and intelligence level of the device.

[0027] Optionally, the air port connection assembly further includes a clamping assembly located on one side of the centering assembly. The clamping assembly includes a first floating seat connected to the base, a second floating seat disposed axially opposite to the first floating seat, a guide rod connecting the first floating seat and the second floating seat, and a third elastic member disposed on the first floating seat and the second floating seat.

[0028] A clamping component is installed on one side of the centering assembly. This component clamps and secures the product under test during the connection test between the centering assembly and the product's air port, preventing displacement due to airflow impact during high-pressure testing. During product centering, the second floating seat of the clamping assembly contacts the pressed portion of the product under test and moves axially under the action of the guide rod and the third elastic element, thereby compressing the third elastic element between the second and first floating seats and providing stable pressure. Preferably, the parameters of the elastic element and the distance between the second and first floating seats are calculated before testing so that the second and first floating seats are in precise contact upon completion of centering, further ensuring the stability of the clamping.

[0029] Optionally, the clamping assembly further includes a limiting member connected to the second floating seat, a pressure plate axially opposite to the limiting member, a universal joint disposed between the limiting member and the pressure plate, and a fourth elastic member with both ends connected to the limiting member and the pressure plate, respectively. The two ends of the universal joint contact the limiting member and the pressure plate, allowing the pressure plate to deflect radially relative to the limiting member. By providing the universal joint, the pressure plate has radial deflection capability, which can adapt to unevenness or installation errors on the surface of the product under test, ensuring full contact between the pressure plate and the product surface, and effectively preventing product deformation caused by localized stress concentration. Specifically, the universal joint can be a sphere.

[0030] Optionally, the driving mechanism includes a high-pressure clamping cylinder mounted on a support platform and a guide assembly. The guide assembly includes a guide sleeve fixed to the support platform and a telescopic rod located within the guide sleeve. The guide sleeve is arranged parallel to the piston rod of the high-pressure clamping cylinder, and the piston rod and telescopic rod of the high-pressure clamping cylinder are respectively connected to the air port connection assembly. The high-pressure clamping cylinder provides a stable axial driving force, which, combined with the parallel guide sleeve and telescopic rod, ensures that the air port connection assembly does not skew or rotate during movement, thus improving alignment accuracy.

[0031] Optionally, the piston rod of the high-pressure clamping cylinder is provided with a locking mechanism, which is used to lock the axial position of the piston rod after the air port connection assembly is sealed with the product under test. Specifically, the locking mechanism locks the piston rod mechanically or hydraulically after sealing, preventing the piston rod from retracting due to pressure fluctuations during the test, reducing the continuous workload of the high-pressure clamping cylinder, and saving energy; the locked state ensures stable sealing pressure, improves the accuracy of test data, and prevents sealing failure caused by power system failure, thus enhancing operational safety.

[0032] When using the airtightness testing device of this application to conduct airtightness testing on the product under test, the process is as follows:

[0033] I. Initial Positioning and Institutional Launch Phase

[0034] The product under test is initially positioned using a positioning fixture to ensure that the test air port is directly below the air port connection assembly. The system reads the current alignment assembly model through a model change identification sensor. After confirming that it matches the product under test, the drive mechanism (high-pressure clamping cylinder) is activated, and its piston rod extends axially, driving the air port connection assembly to move down synchronously through the guide assembly (guide sleeve and telescopic rod).

[0035] II. Manual pre-centering adjustment stage

[0036] By manually adjusting the components to adjust the initial position of the base in the radial plane, the elastic sealing head is driven to roughly align with the center of the product's air inlet, ensuring that the axial deviation is controlled within the preset error, thus providing basic accuracy for automatic alignment.

[0037] III. Automatic Centering and Fine-tuning Stage

[0038] Sealing part introduction and initial guidance: As the piston rod continues to extend, the sealing part (including the elastic sealing head) of the centering component first enters the air port of the product under test, and the bullet end cap (rigidly connected to the floating part sealing part) slides along the inner wall of the interface to achieve initial centering.

[0039] Radial floating compensation of the first guide structure: When the elastic sealing head contacts the bottom of the air port and is subjected to axial resistance, the sliding part of the floating component slides upward along the axial direction of the base accommodating space. At this time, the first guide structure (conical fit, radial dimension expanding away from the sealing head) formed by the outer periphery of the sliding part and the inner wall of the accommodating space provides radial floating margin for the floating component through the conical gap, allowing it to freely offset in the radial plane, initially compensating for the parallel misalignment deviation between the air port and the sealing head, and avoiding rigid collision. The second elastic element (connecting the floating component and the base) is compressed during this process, providing axial buffer force.

[0040] Precise alignment of the second guide structure: As the axial force continues to be transmitted, the second conical surface of the sliding part facing the first slider gradually contacts the first conical surface of the first slider (the second guide structure intervenes). The two sets of conical surfaces are taper-matched, decomposing the axial force into a radial component: if there is an eccentricity between the sealing head and the air port, the radial component drives the floating part to shift in the opposite direction of the eccentricity until the axes of the two coincide. During this process, the first slider is subjected to a reaction force and slides axially along the accommodating space, compressing the first elastic element. Its outer circumference matches the cylindrical surface of the inner wall of the accommodating space to ensure that it moves only along the axial direction, avoiding radial offset from interfering with the alignment accuracy. The first and second elastic elements are always in a compressed state throughout the alignment process, and the force balance ensures that the conical surfaces fit tightly, reducing alignment errors.

[0041] IV. Compression Locking and Gas Circuit Connection Stage

[0042] Adaptive Fit and Rigid Locking of the Clamping Component: Before the centering component completes precise centering, the clamping plate of the clamping component is already in contact with the product surface. As the drive mechanism continues to apply force, the fourth elastic element (connecting the limiting element and the clamping plate) is compressed, providing axial preload; simultaneously, the clamping plate adapts to the unevenness of the product surface through the universal joint, ensuring full contact. When the conical surfaces of the centering components are fully fitted (centering complete), the third elastic element (connecting the first floating seat and the second floating seat) is compressed to its limit position, the first floating seat and the second floating seat are in rigid contact, the clamping force reaches the preset value, and the product under test is stably fixed.

[0043] Piston rod locking and air passage connection: After the centering and clamping actions are completed, the locking mechanism of the high-pressure clamping cylinder is triggered, mechanically locking the axial position of the piston rod to ensure stable sealing pressure. At this time, the air passage inside the floating component is fully connected to the air port of the product under test, and the high-pressure control pipeline begins to introduce test gas into the air passage. The entire process requires no manual intervention and is completed adaptively by the mechanical structure, meeting the cycle time requirements of automated production lines.

[0044] The airtightness testing device of this application achieves efficient and accurate docking for high-pressure airtightness testing through the synergistic effect of the first and second guide structures, combined with the elastic buffering and rigid locking of the clamping components, thus solving the problems of low efficiency and poor sealing reliability of traditional manual alignment.

[0045] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0046] 1. Through the synergistic effect of the first and second guide structures, the positional and shape deviations between the elastic sealing head and the product's air port are automatically compensated, achieving precise alignment. The dual elastic elements are pre-compressed throughout the process to ensure a tight fit after alignment, and combined with the flexible contact of the elastic sealing head, it meets the leak-free sealing requirements under high-pressure testing.

[0047] 2. The clamping assembly, through a combination of a universal joint and an elastic element, adapts to uneven product surfaces, providing stable preload and ensuring full contact of the pressure plate. When alignment is complete, the elastic element compresses to its limit position to achieve rigid locking, effectively preventing product displacement due to airflow impact during high-pressure testing.

[0048] 3. Integrates manual pre-alignment and automatic precision alignment functions, completing the entire process from positioning to sealing and locking without manual intervention. The high-pressure clamping cylinder drive and locking mechanism are linked, and the testing cycle is adapted to the needs of automated production lines, solving the problems of time-consuming and labor-intensive traditional connection methods.

[0049] 4. The base is detachably connected to the adjustment assembly via a changeover plate. During changeovers, only the changeover pin needs to be plugged and unplugged for complete replacement, significantly reducing changeover time. The changeover identification sensor automatically verifies the compatibility between the assembly and the product, avoiding test failures caused by incorrect model numbers, resulting in low maintenance costs.

[0050] 5. After sealing is completed, the locking mechanism mechanically locks the piston rod to prevent retraction caused by pressure fluctuations, reduce the continuous working load of the high-pressure clamping cylinder to save energy, and prevent seal failure caused by power system failure, thereby improving operational safety.

[0051] To make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a schematic diagram of the airtightness testing device in Embodiment 1 of the present invention;

[0054] Figure 2 This is a side view of the airtightness testing device in Embodiment 1 of the present invention;

[0055] Figure 3 This is a schematic diagram of the air inlet connection assembly in Embodiment 1 of the present invention;

[0056] Figure 4 This is a side view of the air inlet connection assembly in Embodiment 1 of the present invention;

[0057] Figure 5 This is a schematic diagram of the centering component in Embodiment 1 of the present invention;

[0058] Figure 6 This is a cross-sectional schematic diagram of the centering component in Embodiment 1 of the present invention;

[0059] Figure 7 This is a cross-sectional schematic diagram of the centering component in Embodiment 1 of the present invention without an elastic element;

[0060] Figure 8 This is a schematic cross-sectional view of the base in Embodiment 1 of the present invention;

[0061] Figure 9 This is a schematic diagram of the engagement state of the first slider and the second slider in Embodiment 1 of the present invention;

[0062] Figure 10 This is a cross-sectional schematic diagram of the first slider and the second slider in the engagement state in Embodiment 1 of the present invention;

[0063] Figure 11 This is a schematic diagram of the first slider in Embodiment 1 of the present invention;

[0064] Figure 12 This is a schematic diagram of the second slider in Embodiment 1 of the present invention;

[0065] Figure 13 This is a schematic diagram of the clamping assembly in Embodiment 1 of the present invention;

[0066] Figure 14 This is a schematic cross-sectional view of the clamping assembly in Embodiment 1 of the present invention;

[0067] Figure 15This is a schematic diagram of the adjustment component in Embodiment 1 of the present invention.

[0068] The reference numerals in the above figures are as follows: 1. Support platform; 11. Connecting seat; 12. Support column; 13. Support plate; 2. Drive mechanism; 21. High-pressure clamping cylinder; 22. Guide assembly; 3. Centering assembly; 31. Base; 311. Mounting seat; 312. Base; 313. Accommodating space; 314. First cylindrical surface; 315. Third conical surface; 32. First slider; 321. Second cylindrical surface; 322. First conical surface; 33. First elastic element; 34. Floating element; 341. Sliding part; 3411. Second conical surface. Surface; 3412, Fourth conical surface; 342, Sealing part; 343, Elastic sealing head; 344, Vent block; 35, Second elastic element; 36, Heightening block; 4, Pressing assembly; 41, First floating seat; 42, Second floating seat; 43, Third elastic element; 44, Guide rod; 45, Limiting element; 46, Pressure plate; 47, Universal joint; 48, Fourth elastic element; 5, Shape changing plate; 6, Adjustment assembly; 61, First connecting plate; 62, X guide rail; 63, Y guide rail; 64, Second connecting plate; 65, Third connecting plate. Detailed Implementation

[0069] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0070] Example 1: See Figure 1 , 2 As shown, an airtightness testing device includes a support platform 1, a drive mechanism 2 mounted on the support platform 1, and an air port connection assembly connected to the drive mechanism 2. The air port connection assembly includes at least one centering component 3, which is used for automatic sealing connection between the airtightness testing device and the air port of the product under test. This device uses a right-handed Cartesian coordinate system as the directional reference: the Z-axis is parallel to the central axis of the base 31 (i.e., the direction of movement of the air port connection assembly), and the XY plane is a plane perpendicular to the Z-axis (used to describe the radial position adjustment or range of movement).

[0071] In an optional implementation, see Figure 1As shown, the support platform 1 includes a connecting seat 11, a support column 12, and a support plate 13. The bottom and top of the support column 12 are fixedly connected to the connecting seat 11, respectively. The bottom connecting seat 11 is used to contact the mounting surface and provide stable support, while the top surface of the top connecting seat 11 is fixedly connected to the bottom surface of the support plate 13, together forming a frame that supports the drive mechanism 2 and the guide assembly 22. The support columns 12 are arranged vertically, and their number can be configured to multiple according to the load-bearing requirements. The bottom connecting seats 11 of each support column 12 can be symmetrically distributed through the positioning structure of the mounting surface to ensure that the support plate 13 is subjected to uniform force. The support plate 13 is a horizontally arranged plate structure, and its top surface serves as the mounting reference surface for fixing the drive mechanism 2 and the guide assembly 22. The relative position of the drive mechanism 2 and the guide assembly 22 is fixed through the connection relationship between the top connecting seat 11 and the support column 12.

[0072] In an optional implementation, see Figure 1 As shown, the driving mechanism 2 includes a high-pressure clamping cylinder 21 and a guide assembly 22 mounted on the support platform 1. The guide assembly 22 includes a guide sleeve fixed to the support plate 13 and a telescopic rod slidably disposed within the guide sleeve. The central axis of the guide sleeve is parallel to the central axis of the piston rod of the high-pressure clamping cylinder 21, and the bottom ends of both are connected to the air port connection assembly via a connector. The high-pressure clamping cylinder 21 serves as a power source; when its piston rod extends along the Z-axis, it synchronously drives the air port connection assembly downwards via the connector. The cooperation between the guide sleeve and the telescopic rod restricts the deflection of the air port connection assembly in the XY plane, ensuring that the centering assembly 3 moves linearly along the Z-axis. The parallel arrangement of the telescopic rod and the piston rod further enhances motion stability, preventing the air port connection assembly from tilting or rotating during movement.

[0073] In an optional embodiment, four guide components 22 are arranged in a rectangular array on the support plate 13 along the circumference of the high-pressure clamping cylinder 21. The guide sleeves of each guide component 22 are connected to the support plate 13 by bolts, and their inner sides are provided with wear-resistant bushings. The bottom ends of the telescopic rods are connected to the centering component 3. The central axes of the four telescopic rods are parallel to the central axis of the piston rod of the high-pressure clamping cylinder 21, and the distance between them is consistent. The structure formed by these four sets of guide components 22 can achieve bidirectional motion constraint in the X / Y direction. The geometric stability of the rectangular layout limits the radial runout of the air port connection component; the symmetrical distribution design ensures that the radial force borne by each guide component 22 is balanced, and with the bushings, the maintenance cycle of the guide components 22 is extended.

[0074] In an optional embodiment, the piston rod of the high-pressure clamping cylinder 21 is provided with a locking mechanism. The locking mechanism may include a locking sleeve connected to the piston rod, circumferentially distributed wedge-shaped locking blocks, a locking cylinder for driving the wedge-shaped blocks, and a position detection sensor. After the centering assembly 3 completes automatic centering and sealing connection with the air port of the product under test, the locking mechanism can mechanically lock the axial position of the piston rod to prevent the piston rod from retracting due to pressure fluctuations during the test. At the same time, it reduces the continuous working load of the high-pressure clamping cylinder 21 to save energy and ensures stable sealing pressure to improve the accuracy of test data.

[0075] In an optional implementation, see Figure 3-5 As shown, the centering assembly 3 includes a base 31 connected to the drive mechanism 2. The base 31 contains a first slider 32 and a floating element 34 that can slide along the Z-axis. A first elastic element 33 is connected between the first slider 32 and the base 31 along the Z-axis, and a second elastic element 35 is connected between the floating element 34 and the base 31 along the Z-axis. The floating element 34 includes a sliding portion 341 opposite to the first slider 32 and a sealing portion 342 connected to the sliding portion 341 for sealing the air port of the product under test. Both the first elastic element 33 and the second elastic element 35 are springs.

[0076] See Figure 6 As shown, the base 31 can adopt a split structure design, including a mounting base 311 and a base 312 located below the mounting base 311 and detachably connected to the mounting base 311. Specifically, the two can be flexibly configured as upper and lower split or left and right split according to the assembly requirements of the floating component 34 and the first slider 32, and a stable combination can be achieved by detachable connection methods such as bolts, pins or buckles. The base 31 has an accommodating space 313 extending through its bottom along the Z-axis direction. The accommodating space 313 has a first space and a second space that are interconnected along the Z-axis direction. The first space is used to accommodate the first slider 32, and the second space is used to accommodate the sliding part 341 of the floating component 34.

[0077] In an optional implementation, see Figure 7 , 8 As shown, the inner wall of the first space can be set as a first cylindrical surface 314. Correspondingly, the outer periphery of the first slider 32 can be configured as a second cylindrical surface 321 that cooperates with the first cylindrical surface 314. Through the cooperation of the first cylindrical surface 314 and the second cylindrical surface 321, the first slider 32 can be effectively constrained to slide linearly only along the Z-axis direction, avoiding radial offset to ensure centering accuracy.

[0078] In an optional embodiment, the inner wall of the second space can be configured as a third conical surface 315, and the outer periphery of the sliding part 341 is correspondingly configured as a fourth conical surface 3412 that mates with the third conical surface 315. The radial dimension of the third conical surface 315 gradually increases along the Z-axis from away from the first space to closer to the first space, thereby forming a conical guide area, providing a composite motion space for the floating member 34 to perform axial sliding and radial floating. The cone angle between the third conical surface 315 and the fourth conical surface 3412 is in the range of 5-45°, preferably 15-30°. To accommodate the sliding part 341 of the floating member 34 extending out of the base 31, the third conical surface 315 can be designed as a non-complete conical segment, with a through hole at its cone point for the sealing part 342 to pass through. Correspondingly, the first conical surface 322 of the first slider 32 facing the sliding part 341 and the second conical surface 3411 of the sliding part 341 facing the first slider 32 can also adopt a non-complete conical surface structure, and a through hole can be opened at the top to accommodate the first elastic member 33.

[0079] See Figure 6 , 7 As shown, the base 31 also includes a limiting member 45 for positioning the first elastic member 33 and the second elastic member 35. This limiting member 45 may include a limiting piece and a limiting rod, wherein the limiting piece protrudes radially from the outer periphery of the limiting rod. Both the first elastic member 33 and the second elastic member 35 are located within the accommodating space 313 and may be elastic elements such as springs. The first elastic member 33 is sleeved on the outside of the limiting rod, with one end abutting against the end face of the first slider 32 opposite to the sliding portion 341, and the other end abutting against the end face of the limiting piece. Similarly, the second elastic member 35 is sleeved on the outside of the limiting rod and located inside the first elastic member 33, with one end extending into the sliding portion 341 and connected to the floating member 34, and the other end abutting against the end of the limiting rod. In the initial state (i.e., when the first elastic member 33 and the second elastic member 35 are not under force), the fourth conical surface 3412 of the sliding part 341 is in contact with the third conical surface 315 of the second space, the sliding part 341 is in contact with the first conical surface 322 and the second conical surface 3411 of the first slider 32, and the second cylindrical surface 321 of the first slider 32 is in contact with the first cylindrical surface 314 of the first space.

[0080] The split structure not only facilitates the processing of complex curved surfaces such as conical and cylindrical surfaces within the accommodating space 313, but also allows for the adaptation of floating parts 34 or first sliders 32 of different sizes by replacing the mounting base 311 or the base 312 according to the needs of different testing scenarios. For example, the mounting base 311 with a third conical surface 315 of different tapers can be replaced to meet diverse centering adjustment needs.

[0081] In an optional implementation, see Figure 7As shown, the base 31 also includes a heightening block 36, which is detachably connected to the side of the mounting base 311 facing away from the base 312, and is used to adjust the distance between the centering component 3 and the product to be tested.

[0082] In an optional implementation, see Figure 9-11 As shown, the first slider 32 is cylindrical in shape, with a second cylindrical surface 321 on its outer periphery that mates with the first cylindrical surface 314 of the first space. This cylindrical surface mate constrains the first slider 32 to slide only axially. One end of the first slider 32 facing the sliding part 341 has a first conical surface 322, which mates with the second conical surface 3411 of the sliding part 341. This conical surface contact achieves radial decomposition of the axial force. The end of the first slider 32 facing away from the sliding part 341 is planar, used to abut against the end of the first elastic member 33.

[0083] The first slider 32 has a cylindrical through hole that runs through the top plane and the bottom conical surface along the axial direction. The through hole is used to accommodate the second elastic member 35, and the axis of the through hole is collinear with the central axis of the first slider 32 to ensure that the second elastic member 35 maintains axial stability during the extension and contraction process.

[0084] In an optional embodiment, the floating component 34 can adopt an integrated structural design, including an integrated sliding part 341 and a sealing part 342. The sliding part 341 has a second conical surface 3411 on the side facing the first slider 32, which mates with the first conical surface 322. The sealing part 342 has an elastic sealing head 343 at its end away from the sliding part 341. The sealing part 342 extends axially from a through hole at the bottom of the base 31, and has an internal air passage leading to the elastic sealing head 343. A vent interface for connecting to a high-pressure pipeline can be provided on the outer periphery of the sealing part 342 for introducing high-pressure test gas. To facilitate the assembly of the integrated floating component 34, the base 31 can adopt a left-right split structure, fixed by bolts or clips, simplifying the processing and assembly of complex surfaces.

[0085] In another alternative implementation, see Figure 7 As shown, the floating component 34 can adopt a split structure design, including a second slider, a vent block 344, a bullet end cap, and an elastic sealing head 343 connected in sequence. See also Figure 12As shown, the second slider constitutes the aforementioned sliding part 341, and its side facing the first slider 32 has a second conical surface 3411. One end of the vent block 344 is connected to the second slider, and the other end is detachably connected to the bullet head via threads or snaps. The end of the bullet head away from the vent block 344 is detachably connected to the elastic sealing head 343. The outer periphery of the vent block 344 has a venting port, and its interior, together with the bullet head and the elastic sealing head 343, forms a through-flow air passage for introducing high-pressure test gas. To improve the air passage sealing performance, a sealing ring can be added to the connection surface between the vent block 344 and the bullet head, or a conical surface fit can be used to achieve self-sealing. The outer periphery of the bullet head can be designed as a conical guide surface to assist in the initial alignment of the elastic sealing head 343 with the air port of the product under test.

[0086] In an optional embodiment, the elastic sealing head 343 is made of an elastic material and is located at the end of the sealing part 342 away from the sliding part 341. Its shape can be designed to fit the structural characteristics of the air port of the product under test (such as conical, spherical, or planar), or it can adopt a universal contour to adapt to different air port shapes through its own deformation. It has an internal channel that leads to the air passage. The elastic material can be made of materials with good compression and rebound properties, such as nitrile rubber, fluororubber, or silicone rubber, to meet the high-pressure sealing requirements and avoid damage to the product's air port.

[0087] During automatic alignment, as the drive mechanism 2 moves the air port connection assembly downwards, the elastic sealing head 343 first enters the air port of the product under test and achieves initial centering through the conical guide surface of the bullet-shaped end cap. When the end of the elastic sealing head 343 contacts the bottom of the air port (flat, inclined, or spherical) and experiences axial resistance, the sliding part 341 of the floating member 34 slides upwards along the axial direction of the accommodating space 313 of the base 31. At this time, the second elastic member 35 is compressed and provides a buffering force. The axial force is decomposed into a radial component through the cooperation of the sliding part 341 and the conical surface of the first slider 32, driving the floating member 34 to adaptively adjust in the radial plane until the elastic sealing head 343 is coaxial with the air port. Subsequently, the high-pressure clamping cylinder 21 continuously applies axial force, causing the elastic sealing head 343 to generate a preset compression amount. Through the elastic deformation of the material, the microscopic unevenness at the bottom of the air port is filled, forming a circumferentially uniform sealing contact, ensuring that the high-pressure test gas (up to 200 bar) is introduced into the product under test without leakage.

[0088] In the split floating component 34 structure, the elastic sealing head 343 and the bullet end cap are detachably connected. When replacing, only the sealing head and the bullet end cap need to be separated, without disassembling the entire air port connection assembly, which can reduce maintenance costs and ensure sealing effect.

[0089] In an optional implementation, see Figure 15As shown, the airtightness testing device also includes an adjustment component 6 connected between the drive mechanism 2 and the base 31, used to adjust the initial position of the base 31 in the radial plane (XY plane) to achieve the coarse adjustment function of the centering component 3. The adjustment component 6 can drive the base 31 to move radially by manual or electric means to adapt to the air port position requirements of different products under test, ensuring that the initial axis deviation between the elastic sealing head 343 and the air port is controlled within a preset range, providing basic accuracy for subsequent automatic centering.

[0090] In an optional embodiment, the base 31 is detachably connected to the adjustment assembly 6 via the changing plate 5, which can be achieved by means of bolts, changing pins, or clips for quick separation. When replacing air port connection assemblies of different specifications, it is not necessary to disassemble the parts one by one; simply remove the changing plate 5 from the adjustment assembly 6 as a whole to complete the replacement of the air port connection assembly, significantly shortening the changeover time.

[0091] In an optional embodiment, the adjusting assembly 6 includes a first connecting plate 61 connected to the piston rod of the high-pressure clamping cylinder 21. The first connecting plate 61 has X guide grooves extending in the X direction on opposite sides. An X guide rail 62 is installed in the X guide grooves. A second connecting plate 64 is connected to the side of the X guide rail 62 facing away from the first connecting plate 61. The second connecting plate 64 has Y guide grooves extending in the Y direction on opposite sides. A Y guide rail 63 is installed in the Y guide grooves. A third connecting plate 65 is connected to the side of the Y guide rail 63 facing away from the second connecting plate 64. The third connecting plate 65 is used to connect the changing plate 5 or the base 31. Through the sliding engagement of the X guide groove and the X guide rail 62, the second connecting plate 64 and the third connecting plate 65 can be driven to move synchronously in the X direction, thereby driving the air port connecting assembly to achieve position adjustment in the X direction; through the sliding engagement of the Y guide groove and the Y guide rail 63, the third connecting plate 65 can be driven to move independently in the Y direction, thereby driving the air port connecting assembly to achieve position adjustment in the Y direction, and finally, through bidirectional XY adjustment, the initial position of the air port connecting assembly in the radial plane is initially adjusted.

[0092] In an optional embodiment, the outer wall of the base 31 is provided with a changeover identification sensor, which can automatically verify the compatibility between the air port connection component and the product under test by identifying the identification information (such as barcode or mechanical code) of the changeover plate 5, and feed the signal back to the control system to avoid test failure or product damage caused by changeover errors, thereby improving the automation and intelligence level of the device.

[0093] In an optional implementation, see Figure 3As shown, the air port connection assembly can be equipped with multiple centering components 3 to adapt to products under test with multi-air port structures. For example, four centering components 3 can be set on the changing plate 5, with the distance between each base 31 being the same as the distance between adjacent air intakes on the product under test. The multiple centering components 3 can be arranged linearly, in a ring, or in a matrix along the radial plane (XY plane), and their number and position can be customized according to the air port distribution characteristics of the product. Each centering component 3 is independently configured with a base 31, a floating part 34, an elastic sealing head 343, and an air passage to ensure that the test media of different air ports do not interfere with each other; at the same time, they share the same drive mechanism 2, and achieve simultaneous centering and sealing of multiple air ports through synchronous axial movement.

[0094] This multi-alignment component 3 configuration scheme can significantly improve the testing efficiency of multi-port products and reduce the number of clamping operations. Through modular design, the port connection modules containing different numbers of alignment components 3 can be quickly replaced according to the product model, and flexible production can be achieved in conjunction with the automated control system.

[0095] In an optional implementation, see Figure 13 As shown, the air inlet connection assembly also includes a clamping assembly 4 located on one side of the centering assembly 3, used to clamp and fix the product under test during the test to prevent displacement caused by the impact of high-pressure airflow. The clamping assembly 4 includes a first floating seat 41 connected to the base 31, a second floating seat 42 disposed opposite to the first floating seat 41 along the Z-axis direction, and a guide rod 44 and a third elastic element 43 connecting the two. The guide rod 44 is disposed along the Z-axis direction to ensure that the second floating seat 42 moves linearly relative to the first floating seat 41. Preferably, multiple guide rods 44 can be disposed at intervals along the extension direction of the floating seats. The third elastic element 43 can be a spring, with both ends abutting against the first and second floating seats 42 respectively, providing axial preload.

[0096] In an optional implementation, see Figure 14 As shown, the clamping assembly 4 also includes a limiting member 45 connected to the second floating seat 42, a pressure plate 46 disposed opposite to it along the Z-axis, and a universal joint 47 and a fourth elastic member 48 disposed between them. The universal joint 47 (which may be a spherical structure) contacts the limiting member 45 and the pressure plate 46 at both ends, allowing the pressure plate 46 to deflect in the radial plane to adapt to unevenness or installation errors on the surface of the product being tested. The fourth elastic member 48 connects the limiting member 45 and the pressure plate 46 axially, providing flexible cushioning to prevent product damage caused by rigid contact. The fourth elastic member 48 may be a spring, and multiple springs may be disposed along the outer periphery of the pressure plate 46.

[0097] During operation, as the drive mechanism 2 moves the air port connection assembly downwards, the clamping assembly 4 moves downwards simultaneously. Through pre-calculation, the pressure plate 46 can simultaneously contact the surface of the product under test during the alignment process. At this time, the fourth elastic element 48 is compressed, and the deflection of the universal joint 47 makes the pressure plate 46 fully adhere to the product surface, forming an initial pre-tightening. When the alignment assembly 3 completes precise alignment, the third elastic element 43 is compressed to its limit position, and the first floating seat 41 and the second floating seat 42 are in rigid contact. At this time, the clamping force reaches the preset value, and the product under test is stably fixed. This structure, through the combination of elastic buffering and rigid locking, ensures stability during high-pressure testing and avoids product deformation caused by local stress concentration.

[0098] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. An airtightness testing device, characterized in that, The system includes a drive mechanism and an air port connection assembly connected to the drive mechanism. The air port connection assembly includes at least one centering component, which includes: a base connected to the drive mechanism and having a receiving space; a first slider slidably disposed within the receiving space along the axial direction of the base; a first elastic element axially connected between the first slider and the base; and a floating element including a sliding portion and a sealing portion, wherein the sliding portion is disposed in the receiving space, the sealing portion extends out of the base and has an elastic sealing head at one end opposite to the sliding portion, and the sealing portion has a through-hole of the elastic element inside. The sealing head has an air passage; a second elastic element is axially connected between the floating element and the base; wherein, the outer peripheral side of the sliding part and the inner wall of the accommodating space form a first guide structure, the radial dimension of the first guide structure is expanded in the direction away from the elastic sealing head, so as to allow the floating element to slide axially and float radially at the same time; the opposite end face of the sliding part and the first slider forms a second guide structure, the second guide structure decomposes the axial force into a radial component through the geometry of the contact surface, so that the floating element can adaptively adjust radially to achieve the sealing between the elastic sealing head and the air port of the product under test; The second guide structure includes: a first conical surface disposed on the side of the first slider facing the sliding portion; and a second conical surface disposed on the side of the sliding portion facing the first slider, wherein the second conical surface cooperates with the first conical surface; The first guide structure includes: a first conical surface disposed on the outer periphery of the sliding part; and a second conical surface disposed on the inner wall of the accommodating space, wherein the first conical surface and the second conical surface are conical surfaces or pyramidal surfaces, and the second conical surface cooperates with the first conical surface.

2. The airtightness testing device according to claim 1, characterized in that, The outer periphery of the first slider is a cylindrical or prismatic surface, and the inner wall of the accommodating space is provided with a matching cylindrical or prismatic surface.

3. The airtightness testing device according to claim 1, characterized in that, The airtightness testing device also includes an adjustment component connected between the drive mechanism and the base, the adjustment component being used to adjust the initial position of the base in the radial plane.

4. The airtightness testing device according to claim 3, characterized in that, The base includes a shape-changing plate that is detachably connected to the adjustment assembly.

5. The airtightness testing device according to claim 4, characterized in that, The air port connection assembly also includes a replacement identification sensor, which is disposed on the outer side wall of the base and is used to detect the matching status between the product under test and the air port connection assembly.

6. The airtightness testing device according to claim 1, characterized in that, The air inlet connection assembly further includes a clamping assembly located on one side of the centering assembly. The clamping assembly includes a first floating seat connected to the base, a second floating seat disposed axially opposite to the first floating seat, a guide rod connecting the first floating seat and the second floating seat, and a third elastic member disposed between the first floating seat and the second floating seat.

7. The airtightness testing device according to claim 6, characterized in that, The clamping assembly further includes a limiting member connected to the second floating seat, a pressure plate disposed axially opposite to the limiting member, a universal joint disposed between the limiting member and the pressure plate, and a fourth elastic member with its two ends respectively connected to the limiting member and the pressure plate; the two ends of the universal joint are in contact with the limiting member and the pressure plate respectively, so as to allow the pressure plate to deflect relative to the limiting member in a radial plane.

8. The airtightness testing device according to claim 1, characterized in that, The driving mechanism includes a high-pressure clamping cylinder mounted on a support platform and a guide assembly. The guide assembly includes a guide sleeve fixed on the support platform and a telescopic rod located inside the guide sleeve. The guide sleeve is arranged parallel to the piston rod of the high-pressure clamping cylinder. The piston rod and the telescopic rod of the high-pressure clamping cylinder are respectively connected to the air port connection assembly.

9. The airtightness testing device according to claim 8, characterized in that, The piston rod of the high-pressure clamping cylinder is provided with a locking mechanism, which is used to lock the axial position of the piston rod after the air port connection assembly is sealed with the product to be tested.

Images