An airtightness testing fixture

Abstract

This utility model belongs to the technical field of airtightness testing equipment, specifically referring to an airtightness testing fixture, including a base and multiple testing connectors disposed on the base. An air supply channel is formed within the base, and an air delivery channel communicating with the air supply channel is formed within each testing connector. A check valve core is slidably fitted within a receiving groove below the air delivery channel at the lower end of the testing connector. An elastic reset element is provided between the check valve core and the receiving groove. Air vents are formed on the periphery of the check valve core, and a sealing head extending into the air supply channel is provided at the bottom. A sealing element is provided on the base corresponding to the sealing head. When compressed air is introduced into the air supply channel, the air pressure pushes the check valve core upward, creating a gap between the sealing head and the sealing element. Air flows into the air delivery channel through the air vents from the air supply channel. When the air pressure disappears, the elastic reset element drives the check valve core to reset, and the sealing head and sealing element adhere, blocking the connection between the two channels. This utility model achieves independent on / off switching of the testing station, effectively avoiding mutual interference between stations.

Description

Technical Field

[0001] This utility model belongs to the technical field of airtightness testing equipment, and specifically refers to an airtightness testing fixture. Background Technology

[0002] Air tightness testing fixtures are key equipment in valve production and quality inspection. They are used to test the air tightness of various valves by introducing compressed air to determine the valve's sealing performance and ensure that there is no gas leakage in the valve during actual use.

[0003] Existing valve airtightness testing fixtures use a straight-through air path design for the base and testing connectors, lacking an independent one-way check structure. Leaks at a single station or disassembly can cause depressurization of the common air supply channel in the base, directly affecting normal testing at other stations. This prevents independent pressure maintenance and on / off control at each station, significantly reducing testing efficiency. Therefore, there is an urgent need for an airtightness testing fixture that allows for independent on / off control of each testing station and avoids mutual interference between stations. Utility Model Content

[0004] This invention features a sliding-fit check valve core between the testing connector and the substrate, which, together with an elastic reset component, a sealing head, and a sealing component, forms a unidirectional conduction structure. This enables independent on / off switching and unidirectional check valve operation at the testing station, thereby solving the problems mentioned in the background art.

[0005] The purpose of this utility model is achieved as follows: an airtightness testing fixture includes a base and multiple testing connectors disposed on the base. An air supply channel is provided inside the base, and an air delivery channel communicating with the air supply channel is provided inside each testing connector.

[0006] The detection connector has a receiving groove at its lower end and below the air supply channel. A check valve core is slidably fitted inside the receiving groove, and an elastic reset element is provided between the check valve core and the receiving groove.

[0007] The check valve core has a vent hole on its periphery and a sealing head at its bottom that extends into the air supply channel. A sealing element is provided on the base corresponding to the position of the sealing head.

[0008] When compressed air is introduced into the air supply channel, the air pressure pushes the check valve core upward, and a gap is formed between the sealing head and the sealing element. Air flows into the air delivery channel through the vent hole. When the air pressure disappears, the elastic reset element drives the check valve core to reset, and the sealing head and the sealing element fit together to block the connection between the two channels.

[0009] The present invention is further configured such that the outer peripheral wall of the check valve core is provided with a flange portion, the flange portion slidingly engaging with the groove wall of the receiving groove to guide the axial movement of the check valve core.

[0010] The present invention is further configured such that the sealing head is a conical truncated structure, the conical surface of the conical truncated structure is gradually reduced inward into the air supply channel and is adapted to the sealing element.

[0011] The present invention is further configured such that a positioning boss is integrally formed on the periphery of the sealing head, and the positioning boss is used to limit the downward reset position of the check valve core.

[0012] The present invention is further configured such that the substrate is a hollow square tube structure, one end of the substrate is provided with a gas source interface communicating with the gas supply channel, and the other end is closed.

[0013] The present invention is further configured such that the sealing element is a sealing ring, which is embedded in the upper surface of the substrate and abuts against the sealing head.

[0014] The present invention is further configured such that the elastic reset member is a reset spring, and the check core has an internal receiving groove, with one end of the reset spring abutting the bottom of the receiving groove and the other end abutting the top of the receiving groove.

[0015] By adopting the above technical solution, the beneficial effects that this utility model can achieve are:

[0016] 1. By cooperating with the check valve core, elastic reset component, sealing head, and sealing component, independent on / off switching and unidirectional check valves are achieved at the testing station, improving the independence and stability of multi-station testing.

[0017] 2. By using a conical structure in the sealing head with the cone surface gradually narrowing into the air supply channel, the air pressure bearing area is increased and the check valve core is pushed upward, which improves the sensitivity of the check valve core's movement and the air passage conduction efficiency.

[0018] 3. By using a flange on the check valve core that slides into the receiving groove and a conical platform with a positioning boss for limiting, the axial movement of the check valve core is ensured, jamming and reset offset are avoided, and the overall service life and testing reliability of the tooling are improved. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 This is a first cross-sectional structural diagram of the present invention;

[0021] Figure 3 yes Figure 2 A magnified structural diagram of part A;

[0022] Figure 4 This is a schematic diagram of the second cross-sectional structure of this utility model;

[0023] Figure 5 yes Figure 4 A magnified structural diagram of part B.

[0024] The attached figures are labeled as follows: 1. Base; 2. Detection connector; 3. Air supply channel; 4. Air delivery channel; 5. Receiving groove; 6. Check valve core; 7. Elastic reset element; 8. Vent hole; 9. Sealing head; 10. Sealing element; 11. Flange; 12. Positioning boss; 13. Air source interface; 14. Receiving groove. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. See also: Figure 1-5 :

[0026] Example 1:

[0027] This embodiment provides an airtightness testing fixture, including a base 1 and a plurality of testing connectors 2 disposed on the base 1. The base 1 has an air supply channel 3 inside, and the testing connectors 2 have an air delivery channel 4 communicating with the air supply channel 3 inside.

[0028] The detection connector 2 is provided with a receiving groove 5 at its lower end and below the air supply channel 4. A check valve core 6 is slidably fitted inside the receiving groove 5. An elastic reset member 7 is provided between the check valve core 6 and the receiving groove 5.

[0029] The check valve core 6 has a vent hole 8 on its periphery and a sealing head 9 extending into the air supply channel 3 at its bottom. A sealing element 10 is provided on the base 1 at the position corresponding to the sealing head 9.

[0030] When compressed air is introduced into the air supply channel 3, the air pressure pushes the check valve core 6 upward, and the sealing head 9 and the sealing element 10 form a gap. The air flows into the air delivery channel 4 through the air supply channel 3 via the vent hole 8. When the air pressure disappears, the elastic reset element 7 drives the check valve core 6 to reset, and the sealing head 9 and the sealing element 10 fit together to block the connection between the two channels.

[0031] The base 1 of this airtightness testing fixture is a hollow square tube structure with a through hole extending along its length inside, serving as an air supply channel 3 and a common gas delivery channel for the fixture. One end of the base 1 has an integrally formed air source interface 13 connected to the air supply channel 3 for connecting to an external compressed air source; the other end is fully sealed by welding a sealing plate, which fits tightly against the end face of the base 1 to effectively prevent gas leakage from the air supply channel 3. Multiple testing connectors 2 are arranged at intervals along the length of the upper surface of the base 1. The lower end of each testing connector 2 is fitted to the upper surface of the base 1 and fixed by circumferential welding. The inner wall of the upper end of each connector has an internal thread structure, which can be threaded to the connection end of the valve to be tested, allowing for detachable clamping of the valve. The test connector 2 has an axial air supply channel 4 inside. The lower end of the air supply channel 4 is connected to the air supply channel 3 of the base 1. Compressed air can enter the air supply channel 4 through the air supply channel 3 and finally be delivered to the valve to be tested to complete the air supply operation for air tightness testing.

[0032] At the lower end of the detection connector 2, directly below the air supply channel 4, there is a groove structure extending axially, namely the receiving groove 5. The inner wall of the receiving groove 5 has a guide boss extending axially, and a check valve core 6 is slidably fitted inside. The outer peripheral wall of the check valve core 6 has a flange portion 11, and the side wall of the flange portion 11 has a guide groove adapted to the guide boss. The guide boss is embedded in the guide groove and forms a sliding fit. This structure can restrict the circumferential rotation of the check valve core 6, allowing it to move up and down along the axial direction of the receiving groove 5 only.

[0033] An elastic reset element 7 is provided between the check valve core 6 and the receiving groove 5. In this design, a reset spring is selected as the elastic reset element 7. The check valve core 6 has a receiving groove 14 inside. One end of the reset spring abuts against the bottom of the receiving groove 14, and the other end abuts against the top of the receiving groove 5. The elastic force of the reset spring is stable and can form a gapless abutment fit with the receiving groove 14 and the receiving groove 5, which can accurately realize the reset action of the check valve core 6. Moreover, it is always in a pre-tightened state, providing a continuous elastic force for the reset of the check valve core 6. This pre-tightening state is achieved through axial compression during assembly. During assembly, after the return spring is placed into the receiving groove 14 of the check core 6, the check core 6 is pushed to move into the receiving groove 5, so that the return spring abuts against the top of the receiving groove 5 and generates a preset axial compression amount. Then, the flange 11 of the check core 6 is guided by the receiving groove 5 to achieve positioning, ensuring that the return spring does not loosen or shift when the tooling is not in operation, and ensuring the timeliness and stability of the return core 6's reset action.

[0034] The check valve core 6 has several evenly distributed vent holes 8 on its periphery. These vent holes 8 are through-hole structures that penetrate the sidewall of the check valve core 6 and are connected to the air supply channel 4 of the detection connector 2, serving as the gas flow channel between the air supply channel 3 and the air supply channel 4. A sealing head 9 is integrally formed at the bottom of the check valve core 6. The sealing head 9 has a conical truncated pyramid structure, with its conical surface gradually tapering inwards towards the air supply channel 3, extending vertically downwards into the air supply channel 3 of the base 1. An annular positioning boss 12 is also integrally formed on the periphery of the conical truncated pyramid. The positioning boss 12 extends into the air supply channel 3 along with the sealing head 9, and its lower end face can abut against the inner wall of the air supply channel 3 of the base 1, thereby limiting the downward reset position of the check valve core 6.

[0035] An annular mounting groove is formed on the upper surface of the base 1, corresponding to the position of the sealing head 9. A sealing element 10 is embedded in the groove. In this design, the sealing element 10 is a sealing ring. The outer ring of the sealing ring is tightly fitted to the inner wall of the mounting groove, and the inner ring protrudes upward from the upper surface of the base 1 and abuts against the lower end face of the sealing head 9. Through the tight fit between the sealing ring and the sealing head 9, the air supply channel 3 and the air delivery channel 4 can be sealed and blocked.

[0036] The working principle of this airtightness testing fixture is as follows: When an airtightness test is required on a valve, compressed air is introduced into the air supply channel 3 through the air source interface 13 at one end of the base 1. The air pressure in the air supply channel 3 acts simultaneously on the conical surface and the lower end face of the sealing head 9. The tapered conical surface of the conical platform can convert the radial airflow pressure into an axial upward thrust. This thrust, together with the upward air pressure borne by the end face, forms a resultant force, pushing the check valve core 6 upward along the guide boss in the receiving groove 5. At the same time, the conical surface of the conical platform can also provide a smooth transition guide for the airflow, reducing the airflow resistance.

[0037] When the check valve core 6 moves upward, it will cause the bottom of the receiving groove 14 to squeeze the return spring, further compressing the return spring. At the same time, the sealing head 9 at the bottom of the check valve core 6 separates from the sealing ring on the base 1 and forms a gap. The compressed air in the air supply channel 3 flows through this gap to the periphery of the check valve core 6, and then enters the air supply channel 4 inside the test connector 2 through the air vent 8 on the periphery of the check valve core 6. Finally, it is delivered through the air supply channel 4 to the valve to be tested that is threadedly connected to the test connector 2, completing the air supply operation for testing.

[0038] When the test is completed and the air pressure in the air supply channel 3 disappears, the pre-tightening elastic force of the return spring will push the check valve core 6 downward along the guide boss and reset it. The sealing head 9 at the bottom of the check valve core 6 will also move downward and tightly abut against the sealing ring on the base 1 again. At this time, the gap between the air supply channel 3 and the air delivery channel 4 is closed, and the connection between the two is blocked. During the downward reset process of the check valve core 6, the positioning boss 12 on the periphery of its bottom conical platform will abut against the inner wall of the air supply channel 3, limiting the excessive downward movement of the check valve core 6 and ensuring accurate fit between the sealing head 9 and the sealing ring.

[0039] During the entire up-and-down movement of the check valve core 6, the guide groove of its flange portion 11 always maintains a sliding fit with the guide boss on the inner wall of the receiving groove 5, ensuring that the check valve core 6 moves only along the axial direction without circumferential sway or jamming. Each test connector 2 is independently equipped with the aforementioned check valve core 6, return spring, sealing head 9, and sealing ring mating structure. The actions and mating of each structure do not interfere with each other, enabling independent on / off and unidirectional check at each test station. Compressed air can only flow from the air supply channel 3 of the base 1 to the air delivery channel 4 of the test connector 2, and cannot flow back in the opposite direction.

[0040] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape, and principle of the present utility model should be covered within the scope of protection of the present utility model.

Claims

1. An airtightness testing fixture, comprising a base (1) and a plurality of testing connectors (2) disposed on the base (1), wherein the base (1) has an air supply channel (3) inside, and the testing connectors (2) have an air delivery channel (4) communicating with the air supply channel (3) inside, characterized in that: The detection connector (2) has a receiving groove (5) at its lower end and below the air supply channel (4). A check valve core (6) is slidably fitted inside the receiving groove (5). An elastic reset member (7) is provided between the check valve core (6) and the receiving groove (5). The check valve core (6) has a vent hole (8) on its periphery and a sealing head (9) extending into the air supply channel (3) at its bottom. A sealing element (10) is provided on the base (1) at the position corresponding to the sealing head (9). When compressed air is introduced into the air supply channel (3), the air pressure pushes the check core (6) to move upward, and the sealing head (9) and the sealing element (10) form a gap. The air flows into the air delivery channel (4) through the air vent (8) from the air supply channel (3). When the air pressure disappears, the elastic reset element (7) drives the check core (6) to reset, and the sealing head (9) and the sealing element (10) fit together to block the connection between the two channels.

2. The airtightness testing fixture according to claim 1, characterized in that, The outer peripheral wall of the check valve core (6) is provided with a flange (11), which slides with the groove wall of the receiving groove (5) to guide the axial movement of the check valve core (6).

3. The airtightness testing fixture according to claim 1, characterized in that, The sealing head (9) is a conical structure, and the conical surface of the conical platform is gradually reduced inward into the air supply channel (3) and adapted to the sealing element (10).

4. The airtightness testing fixture according to claim 1, characterized in that, The sealing head (9) has an integrally formed positioning boss (12) on its periphery, which is used to limit the downward reset position of the check valve core (6).

5. The airtightness testing fixture according to claim 1, characterized in that, The substrate (1) is a hollow square tube structure. One end of the substrate (1) is provided with a gas source interface (13) that is connected to the gas supply channel (3), and the other end is closed.

6. The airtightness testing fixture according to claim 1, characterized in that, The sealing element (10) is a sealing ring, which is embedded in the upper surface of the substrate (1) and abuts against the sealing head (9).

7. The airtightness testing fixture according to claim 1, characterized in that, The elastic reset component (7) is a reset spring. The check core (6) has a receiving groove (14) inside. One end of the reset spring abuts against the bottom of the receiving groove (14), and the other end abuts against the top of the receiving groove (5).

Images