Airtightness detection tool for explosion-proof valve of automobile battery pack

Abstract

The invention relates to an air tightness test tool. An air tightness detection tool for an anti-explosion valve of an automobile battery pack comprises a shell, and an inner body capable of moving axially is arranged in the shell; one end of the inner body is a sealing end contacted with the explosion-proof valve, the other end of the inner body is a connecting end connected with an external air pipe, the sealing end is provided with a sealing ring, the sealing ring is fixed on the inner body through a limiting ring, and the inner diameter of the limiting ring is in clearance fit with a valve core of the explosion-proof valve. The air tightness detection tool for the explosion-proof valve of the automobile battery pack is simple and compact in structure, convenient to operate and good in sealing performance, so that the test accuracy is guaranteed. The air tightness detection tool for the explosion-proof valve of the battery pack solves the technical problems that a sealing ring of the air tightness detection tool for the explosion-proof valve of the battery pack is easy to leak air, time-consuming and labor-consuming to operate and complex in structure in the prior art.

Description

Technical Field

[0001] This invention relates to an airtightness testing fixture, and more particularly to an airtightness testing fixture for an explosion-proof valve of an automotive battery pack. Background Technology

[0002] Battery packs for new energy vehicles generate a significant amount of heat during operation, leading to increased internal pressure. Without effective pressure relief measures, this poses a major safety hazard to new energy vehicles. Therefore, manufacturers have installed explosion-proof valves on their battery packs. However, the unique design characteristics of these valves present a considerable challenge to testing the airtightness of the battery packs.

[0003] Currently, the standard tooling for testing the airtightness of battery packs uses a folding handle to compress / extend an internal spring, enabling the vacuum suction cup (strong magnet) to move in and out and open the explosion-proof valve. O-rings or custom-shaped sealing rings are then used to seal the explosion-proof valve using the pressure of the spring. However, the folding handle is prone to getting stuck to other objects under the vehicle in the working position, affecting the effectiveness of the test. Furthermore, the vacuum negative pressure method requires a continuous air supply during testing, causing the air compressor of the testing equipment to operate continuously, increasing energy consumption and shortening its lifespan. Due to the relatively constant spring force and its subsequent force decay, the tooling requires high concentricity. Using this method to drive the sealing ring to seal the explosion-proof valve body is not entirely reliable, easily leading to air leakage at the sealing ring and causing the airtightness test to fail. Summary of the Invention

[0004] This invention provides a simple and compact structure, convenient operation, and good sealing performance, thereby ensuring the accuracy of testing for the airtightness of an explosion-proof valve in an automotive battery pack. It solves the technical problems of existing airtightness testing fixtures for battery pack explosion-proof valves, such as easy leakage of the sealing ring, time-consuming and labor-intensive operation, and complex structure.

[0005] The above-mentioned technical problem of the present invention is solved by the following technical solution: a gas tightness testing fixture for an explosion-proof valve of an automotive battery pack, comprising a housing, and an axially movable inner body within the housing; one end of the inner body is a sealing end that contacts the explosion-proof valve, and the other end of the inner body is a connecting end that connects to an external air pipe; the sealing end is provided with a sealing ring, which is fixed to the inner body by a limiting ring, the inner diameter of which is clearance-fitted with the valve core of the explosion-proof valve. By setting the limiting ring, the sealing ring can be well fixed to the end face of the inner body, preventing it from falling off or deforming. A space for accommodating the sealing ring is formed between the limiting ring and the inner wall of the sealing end of the inner body, and the inner diameter of the sealing ring, limited by the limiting ring, will not become out of round. However, existing O-ring seals often deform during use, easily blocking the air inlet and affecting normal operation; some existing sealing ring structures are also prone to falling off during movement, affecting the test results. The presence of the rigid limiting ring ensures that there is always an air intake gap between the limiting ring and the valve core, thereby guaranteeing air intake and improving the accuracy of the testing fixture.

[0006] Preferably, the sealing end of the inner body is provided with an annular groove, and the sealing ring includes a sealing ring body and a sealing ring fixing part, the sealing ring fixing part being located within the annular groove. First, the fixing plate of the sealing ring is placed within the annular groove, and then a limiting ring is placed within the inner diameter of the sealing ring, fixing the limiting ring to the inner body. This achieves the fixation of the sealing ring's position and constrains the deformation of the sealing ring's inner diameter by the limiting ring.

[0007] Preferably, the sealing ring has an L-shaped cross-section and includes a sealing ring body and a sealing ring fixing part. The sealing ring body is located between the limiting ring and the inner wall of the inner body sealing end, and the sealing ring fixing part is located at the sealing end of the inner body.

[0008] Preferably, the end faces of the inner sealing end, the sealing ring, and the limiting ring form a stepped surface. The end face of the inner sealing end is the highest and located on the outermost layer. The sealing ring is located inside the end face of the sealing end, protecting it from damage before it reaches the valve body end face. After the sealing ring contacts the valve body end face, the end face of the limiting ring is lower than the sealing ring, which constrains the deformation of the sealing ring and allows it to fit more closely to the valve body surface, improving the sealing effect.

[0009] Preferably, the inner body includes an inner body main body and an inner body connecting body. The outer circumferential surface of the inner body connecting body is threaded, and an operating disc is threadedly connected to the inner body connecting body. The inner body main body is located inside the outer shell, and the inner body connecting body is located outside the outer shell. The outer circumferential surface of the inner body main body is provided with a protrusion, and a guide groove is provided on the inner wall of the outer shell, with the protrusion located within the guide groove. The large-pitch thread enables rapid axial movement of the inner body, allowing for quick switching between opening and closing states.

[0010] Preferably, the inner body includes an inner body main body and an inner body connector. A magnet receiving groove is formed at the center of the inner body main body, and an air inlet groove is formed at the bottom of the magnet receiving groove. An air inlet hole is formed at the bottom of the air inlet groove, and a portion of the air inlet groove is located outside the magnet receiving groove. The air inlet groove is lower than the magnet receiving groove, saving space and making the structure more compact. The two ends of the air inlet groove are located outside the magnet receiving groove, thus providing a passage for gas, preventing it from being blocked by the magnets installed inside the magnet receiving groove, allowing the gas to flow out within the air inlet groove.

[0011] Preferably, a magnet is installed in the magnet receiving groove, and a space for valve core movement is left between the magnet and the end face of the inner body. The valve core is attracted by the magnet and moves towards the inner body, thereby opening the air inlet of the explosion-proof valve, allowing air to enter for sealing testing. Using a strong magnet to open the explosion-proof valve reduces energy consumption and effectively extends the service life of the testing equipment.

[0012] Preferably, the limiting ring includes a limiting ring body and a limiting ring fixing part. The limiting ring body is connected to the sealing ring, and the limiting ring fixing part is a plane parallel to the end face of the inner body. The limiting ring fixing part is fixed to the end face of the inner body, and the center of the limiting ring fixing part has a through hole for accommodating a magnet. Air grooves corresponding to the air inlet grooves on the inner body are formed on both sides of the through hole. The limiting ring has an L-shaped cross-section and a very thin ring body, allowing for more design space for the sealing ring. The limiting ring fixing part is a plane, facilitating the fixing of the limiting ring and the sealing ring.

[0013] Preferably, one end of the housing is connected to the explosion-proof valve, and the other end of the housing is threaded to the rear cover. A snap-fit ​​protrusion is provided on the end face of the housing connected to the explosion-proof valve, with an arc greater than π and less than 2π. In the structure for connecting and fixing with the explosion-proof valve, the housing is designed with a radius-exceeding snap ring, making the tooling more reliably and stably fixed to the explosion-proof valve.

[0014] Therefore, the airtightness testing fixture for an explosion-proof valve of an automotive battery pack of the present invention has the following advantages: 1. The overall structure is compact and small in size, solving the problem that the large fixture body cannot effectively meet the actual operating space; 2. The explosion-proof valve is opened by a magnet, which is simple to operate and eliminates the need for negative pressure to open the explosion-proof valve, thus reducing energy consumption; 3. The internal body is moved by a large-pitch operating disc, which improves the force application mechanism of the fixture and ensures that the sealing ring is 100% pressed against the explosion-proof valve; 4. The sealing ring is restricted by a limit ring to prevent it from moving or falling off. Attached Figure Description

[0015] Figure 1 This is a 3D view of a tooling for testing the airtightness of an explosion-proof valve for an automotive battery pack.

[0016] Figure 2 yes Figure 1 A 3D view showing an explosion-proof valve installed in the middle.

[0017] Figure 3 yes Figure 2 Exploded view.

[0018] Figure 4 yes Figure 1 A 3D image with the outer shell removed.

[0019] Figure 5 It is a three-dimensional diagram of the interior.

[0020] Figure 6 It is a 3D view of the outer shell.

[0021] Figure 7 yes Figure 2 A cross-sectional view of the valve core before it is opened.

[0022] Figure 8 yes Figure 2 A cross-sectional view of the valve core when it is open.

[0023] Figure 9 yes Figure 5 A magnified view of point A. Detailed Implementation

[0024] The technical solution of the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0025] Example: like Figure 1 and 2 As shown, a gas tightness testing fixture for an explosion-proof valve in an automotive battery pack includes a cylindrical outer shell 1 with a through hole at its center. An axially movable inner body 3 is installed inside the outer shell 1. An explosion-proof valve 7 is connected to one end of the outer shell 1, and a rear cover 2 is threaded to the other end. The inner body 3 is located within the cavity formed by the outer shell 1 and the rear cover 2. The end of the outer shell 1 connected to the explosion-proof valve 7 is designed with an arc-shaped end face exceeding its radius. A snap-fit ​​protrusion 8 is formed on the arc-shaped end face, which snaps into the snap-fit ​​groove 9 of the explosion-proof valve, thereby fixing the outer shell 1 to the explosion-proof valve 7. A valve core 6 is installed at the center of the explosion-proof valve 7. The valve core 6 can move axially along the explosion-proof valve under the magnetic attraction of a magnet 12 within the inner body. The specific structure of the valve core 6 and the explosion-proof valve 7 is not the subject of this patent application and will not be described in detail here.

[0026] like Figure 3 and 4As shown, one end of the inner body 3 is a sealed end, and the other end of the inner body 3 is a connecting end that connects to the external air pipe 10. An explosion-proof valve 7 is connected to one end of the outer shell 1, and a valve core 6 is installed in the center of the explosion-proof valve 7. A sealing ring 11, a limiting ring 5, a magnet 12 located in the magnet receiving groove of the inner body, a rear cover 2 connected to the end of the outer shell 1, and an operating disc 4 that controls the axial movement of the inner body 3 are arranged axially inside the outer shell 1. An external air pipe 10 is connected to the center of the operating disc 4.

[0027] like Figure 5 As shown, the inner body 3 includes an inner body main body 34 and an inner body connecting body 35. The inner body main body 34 is cylindrical, and the inner body connecting body 35 is integrally formed with the inner body main body 34. The diameter of the inner body connecting body 35 is smaller than that of the inner body main body 34. An annular groove 37 is formed on the annular inner wall of the inner body main body 34, which can be used to fix the sealing ring 11. A circular magnet receiving groove 32 is formed at the center of the bottom surface of the inner body main body 34, and a magnet 12 is installed in the magnet receiving groove 32. An "I"-shaped air intake groove 33 is formed at the center of the bottom of the magnet receiving groove 32. The length of the air intake groove 33 is greater than the diameter of the magnet receiving groove 32, so that the two ends of the air intake groove 33 are outside the magnet receiving groove 32, thus not obstructing the two ends of the air intake groove 33. The air intake groove 33 is connected to the air intake channel 36.

[0028] An air intake channel 36 is located at the center of the inner body connector 35, and the other end of the air intake channel 36 is connected to the external air pipe 10. A thread is formed on the outer circumferential surface of the inner body connector 35, through which an operating disc 4 is connected. The operating disc 4 is located behind the rear cover 2, and the rear cover 2 has a through hole at its center. The rear cover 2 is fitted onto the protrusion at the center of the operating disc 4. Two protrusions 31 are formed on the outer circumferential surface of the inner body 34, and the two protrusions 31 are located on the same diameter.

[0029] like Figure 6 As shown, two corresponding axially arranged guide grooves 81 are formed on the inner wall of the outer casing 1, and the protrusion 31 is located inside the guide grooves 81. In this way, when the operating disc is rotated, the inner body 3 can move axially along the direction of the guide grooves 81.

[0030] like Figure 7 and 8As shown in Figure 9, an "L"-shaped sealing ring 11 is installed on one side of the sealing end of the inner body. The sealing ring 11 includes a sealing ring body 111 and a sealing ring fixing part 112. The sealing ring body 111 is located between the limiting ring 5 and the inner wall of the sealing end of the inner body 3. The sealing ring fixing part 112 is located in the annular groove 37 of the inner body body. First, the sealing ring fixing part 112 is installed into the annular groove 37, and then the annular limiting ring 5 is installed. The limiting ring includes a limiting ring body 53 and a limiting ring fixing part 52. The limiting ring body 53 is connected to the sealing ring 11. The limiting ring fixing part 52 is a plane parallel to the end face of the inner body 3. The limiting ring fixing part 52 is fixed to the end face of the inner body body 34. The center of the limiting ring fixing part 52 is provided with a through hole that can accommodate the installation of a magnet. On both sides of the through hole are air slot holes 51 corresponding to the air inlet slots on the inner body body. The limiting ring fixing part 52 is fixed to the end face of the inner body body 34 by bolts. The limiting ring 53 is a thin ring, approximately 0.3 mm thick. The inner diameter of the limiting ring 5 is clearance-fitted with the valve core 6, ensuring that the valve core 6 can pass through the limiting ring when attracted out of the explosion-proof valve by a magnet. The gap between the two forms a gas passage. The inner body 3, the sealing ring 11, and the limiting ring 5, from the outside in, connect at their end faces to form a stepped surface. This ensures deformation constraint on the sealing ring while protecting it and maintaining unobstructed airflow.

[0031] In use, first insert the snap-fit ​​protrusion on the outer shell into the slot of the explosion-proof valve. Then, rotate the operating disc to quickly move the inner body axially using the large pitch. The inner body drives the magnet to move. When the sealing ring abuts against the explosion-proof valve body, the magnet also approaches the valve core. The magnetic attraction drives the valve core axially, and the end of the valve core enters the space reserved in the inner body. Due to the design of the limiting ring, the deformation of the sealing ring is constrained. Furthermore, the limiting ring and the valve core are in clearance fit, always maintaining an annular gap between them. At this time, the external air pipe draws gas from the air intake channel in the center of the inner body and then through the gaps on both sides of the air intake slot (e.g., Figure 8 (The arrow indicates the direction of gas flow). After the airtightness test is completed, rotate the operating disc in the opposite direction, the inner body is pushed out, and the valve core is reset (the valve core reset structure belongs to the internal structure of the explosion-proof valve and is not the content protected by this patent application. The reset of the valve core in the current explosion-proof valve generally adopts a spring structure, which will not be described in detail here).

[0032] The specific embodiments described herein are merely illustrative of the concept of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to replace them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A gas tightness detection tool for automobile battery pack explosion valve, comprising a shell, an inner body axially movable is arranged in the shell, characterized in that: One end of the inner body is a sealing end in contact with the explosion-proof valve, and the other end of the inner body is a connecting end connected with the external air pipe.

2. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1, characterized in that: The sealing end of the inner body is provided with an annular clamping groove, and the sealing ring comprises a sealing ring main body and a sealing ring fixing part.

3. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1, characterized in that: The cross section of the sealing ring is L-shaped, and the sealing ring comprises a sealing ring main body and a sealing ring fixing part.

4. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1 or 2 or 3, characterized in that: The end face of the sealing end of the inner body, the end face of the sealing ring and the end face of the limiting ring form a stepped surface.

5. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1 or 2 or 3, characterized in that: The inner body comprises an inner body main body and an inner body connecting body, the outer circumferential surface of the inner body connecting body is provided with threads, an operating disc is connected to the inner body connecting body through threads, the inner body main body is located in the shell, the inner body connecting body is located outside the shell, a protrusion is arranged on the outer circumferential surface of the inner body main body, a guide groove is arranged on the inner wall of the shell, and the protrusion is located in the guide groove.

6. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1 or 2 or 3, characterized in that: The inner body comprises an inner body main body and an inner body connecting body, a magnet accommodating groove is arranged in the center of the inner body main body, an air inlet groove is further arranged in the groove bottom of the magnet accommodating groove, an air inlet hole is arranged in the groove bottom of the air inlet groove, and a part of the air inlet groove is located outside the magnet accommodating groove.

7. The airtightness detection tool for an explosion valve of an automobile battery pack according to claim 6, characterized in that: A magnet is installed in the magnet accommodating groove, and a valve core movement space is left between the magnet and the end face of the inner body main body.

8. The airtightness detection tool for the explosion valve of the automobile battery pack according to claim 1 or 2 or 3, characterized in that: The limiting ring comprises a limiting ring ring body and a limiting ring fixing part, the limiting ring ring body is in contact with the sealing ring, and the limiting ring fixing part is a plane parallel to the end face of the inner body main body.

9. The gas tightness detection tool for the explosion valve of the automobile battery pack according to claim 1 or 2 or 3, characterized in that: The other end of the shell is threadedly connected with the rear cover, the end face of the end of the shell in contact with the explosion-proof valve is provided with a clamping protrusion, and the curvature of the clamping protrusion is greater than π and less than 2π.

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