A kind of anti-adsorption gas sampling bag quick replacement valve

Abstract

The utility model relates to gas sampling and analysis detection equipment technical field discloses a kind of anti-adsorption gas sampling bag quick replacement valve.The valve includes valve body, air inlet pipe, collection bag, and clamping mechanism and quick release mechanism.Clamping mechanism is arranged at the connecting place of air inlet pipe and valve body, by limiting component locking outer tube one and outer tube two, sealing ball is opened using push column to realize gas circuit conduction;Quick release mechanism is arranged at the connecting place of valve body and collection bag, using connecting ring radial contraction to make restriction block clamped into valve seat limiting groove to realize quick locking.The utility model solves the problem that air inlet pipe is easy to fall off by clamping mechanism, and ensures that gas circuit is automatically switched on and off;Quick release mechanism realizes the quick dismounting device of valve body and collection bag, cooperates with anti-adsorption material to effectively prevent sample gas adsorption, with the advantages of stable connection, convenient operation, good sealing and high sampling precision.

Description

Technical Field

[0001] This utility model relates to the technical field of gas sampling and analysis equipment, and in particular to a quick replacement valve for an anti-adsorption gas sampling bag. Background Technology

[0002] In fields such as environmental monitoring, petrochemicals, and scientific research, gas sampling bags are widely used for the collection and storage of samples such as volatile organic compounds (VOCs) and odorous gases. Sampling bags are typically equipped with valves to connect to an external gas inlet pipe for introducing gas and to close the gas supply after sampling to preserve the sample.

[0003] However, existing gas sampling bag valves have significant structural defects in their connection during actual use. Typically, the connection between the external air inlet pipe and the valve relies on the flexible interference fit of the hose directly onto the valve's barbed interface. This connection method is prone to loosening after prolonged use or as the tubing ages, causing the air inlet pipe to accidentally detach during sampling, resulting in sampling failure or sample contamination. Conversely, if the connection is too tight, disassembly is extremely difficult and may even damage the tubing or valve body.

[0004] Furthermore, existing technologies mostly use fixed nuts or adhesive to connect valves to the sampling bag body. When it is necessary to replace a contaminated valve or clean the inside of the valve to meet the high cleanliness requirements for anti-adsorption, the traditional connection structure is cumbersome to disassemble and assemble, often requiring auxiliary tools, which cannot meet the efficient operation requirements for rapid replacement of valve components during on-site sampling.

[0005] Therefore, this utility model proposes a quick replacement valve for an anti-adsorption gas sampling bag to address the shortcomings of the prior art. Utility Model Content

[0006] In view of the common problems in existing gas sampling bag valves, such as the air inlet pipe connection being prone to accidental detachment due to loosening, the connection between the valve and the sampling bag being cumbersome to disassemble and assemble and make it difficult to meet the needs of rapid on-site replacement, and the common materials being prone to adsorbing sample gas and causing sample contamination, this utility model aims to provide a gas sampling bag rapid replacement valve with an improved structure that can effectively solve the above problems.

[0007] This utility model provides a quick replacement valve for an anti-adsorption gas sampling bag, comprising: a valve body, an air inlet pipe, a collection bag, a snap-fit ​​mechanism disposed between the air inlet pipe and the valve body, and a quick-release mechanism disposed between the valve body and the collection bag.

[0008] The air intake pipe is connected to one end of the valve body, and the collection bag is connected to the other end of the valve body. The snap-fit ​​mechanism is a split-connection type, including an outer tube one fixedly connected to the valve body and an outer tube two fixedly connected to the air intake pipe. The outer tube one is internally threaded with a connecting rod one, and a spring is fixedly connected to one end of the connecting rod one. A sealing ball is fixedly connected to the other end of the spring. A push post is fixedly connected to the side of the sealing ball opposite to the spring. The outer tube two is internally fixedly connected with a connecting rod two. A limiting component is sleeved on the outside of the outer tube one and the outer tube two.

[0009] Furthermore, the outer tube one, the outer tube two, and the limiting component are combined by means of threaded locking, and the limiting component is used to fix the outer tube one and the outer tube two in place.

[0010] Meanwhile, the quick-release mechanism includes a connecting block fixedly connected to the valve body and a valve seat fixedly connected to the collection bag. The outer wall of the valve seat is provided with a limiting groove. A connecting ring is rotatably connected to the connecting block. Multiple shrink blocks are slidably connected inside the connecting ring. The shrink blocks extend to the valve seat and are engaged in the limiting groove. The connecting ring drives the shrink blocks to move so as to lock and separate the valve body from the collection bag.

[0011] Preferably, the sealing ball is slidably fitted to the inner wall of the outer tube one, and the pusher extends along the axial direction of the outer tube one; when the outer tube one is connected to the outer tube two, the pusher extends into the interior of the outer tube two and abuts against the end face of the connecting rod two, and the sealing ball is in the open state of compressing the spring, thereby realizing automatic air passage opening during the air intake pipe connection process.

[0012] Preferably, a limiting ring is fixedly connected to the end of the outer tube two that is away from the air intake pipe. The limiting ring is sleeved on the outer periphery of the connecting rod two, and the connecting rod two is threaded to the inner wall of the outer tube two through external threads. The limiting ring is used to limit the position of the connecting rod two and assist in internal sealing.

[0013] Preferably, the limiting component includes a limiting ring and a thread 1 disposed on the inner wall of the limiting ring. The limiting ring is connected across the joint between the outer tube 1 and the outer tube 2, and the limiting ring is threadedly fastened to the outer wall of the outer tube 1 and the outer wall of the outer tube 2 respectively by the thread 1, thereby preventing the intake pipe from loosening and falling off by mechanical thread locking.

[0014] Preferably, the inner wall of the connecting ring is provided with a second thread, and the outer wall of the shrink block is provided with a protrusion or thread structure that matches the second thread. When the connecting ring rotates relative to the connecting block, the second thread drives multiple shrink blocks to converge radially inward, thereby achieving rapid clamping and fixing by using a rotational drive method.

[0015] Preferably, each of the contraction blocks is fixedly connected to a limiting block at the end away from the connecting block. The limiting block protrudes from the inner surface of the contraction block, and the shape of the limiting block is adapted to the cross-sectional shape of the limiting groove. The shape fit improves the stability of the locking.

[0016] Preferably, the limiting groove is opened along the circumference of the valve seat. When the limiting block is engaged in the limiting groove, the axial position of the valve body is locked to prevent the valve body from axial displacement during operation.

[0017] Preferably, the valve body, the air inlet pipe, the first connecting rod, the second connecting rod, and the inner surface of the collection bag are all made of polytetrafluoroethylene or polyvinylidene fluoride anti-adsorption material to minimize the adsorption loss of sample gas during transmission and storage.

[0018] This utility model has the following beneficial effects: 1. This utility model solves the problems of cumbersome operation, difficult disassembly, and difficulty in quick replacement on site in the existing gas sampling bag valve connection method by setting a quick-release mechanism at the connection between the valve body and the collection bag. The internal shrink block is radially contracted by the rotation of the connecting ring, so that the limiting block is accurately locked into the limiting groove outside the valve seat for fixation. This achieves the technical effect of quick disassembly and assembly of the valve body and the collection bag without the need for auxiliary tools, a stable and reliable connection, and greatly improved replacement efficiency.

[0019] 2. This utility model solves the problems of accidental detachment of the air inlet pipe during sampling and leakage of residual gas or mixing of outside air when the air inlet pipe is disassembled. It achieves the technical effects of good anti-detachment performance of the air inlet pipe connection, automatic control of air flow, and effective protection of the air tightness of the sampling. By setting a snap-fit ​​mechanism with a pin-type one-way conduction structure between the air inlet pipe and the valve body, the push column opens the sealing ball to conduct air flow when the outer pipe is connected, and the spring pushes the sealing ball to reset to close the air flow when the outer pipe is separated. In addition, the limiting component locks the outer pipe with threads.

[0020] 3. This utility model solves the problem of traditional metal or ordinary plastic materials easily adsorbing trace amounts of active gas, leading to distorted sampling data, by making the valve body, air inlet pipe, gas-contacting parts inside the clamping mechanism and the inner surface of the collection bag all made of anti-adsorption inert materials such as polytetrafluoroethylene or polyvinylidene fluoride. This achieves the technical effect of reducing sample gas adsorption loss, ensuring the authenticity of gas sample composition, and meeting the requirements of high-precision analysis. Attached Figure Description

[0021] Figure 1 This is a three-dimensional schematic diagram of a rapid replacement valve for an anti-adsorption gas sampling bag proposed in this utility model; Figure 2 This is a schematic diagram of the limiting ring of a rapid replacement valve for an anti-adsorption gas sampling bag proposed in this utility model; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 for Figure 2 Enlarged view of point B in the middle.

[0022] Legend: 1. Valve body; 2. Snap-fit ​​mechanism; 21. Outer tube one; 22. Connecting rod one; 23. Spring; 24. Sealing ball; 25. Push column; 26. Limiting ring; 27. Outer tube two; 28. Connecting rod two; 29. Restriction component; 291. Restriction ring; 292. Thread one; 3. Quick-release mechanism; 31. Connecting block; 32. Connecting ring; 33. Thread 2; 34. Shrink block; 35. Restricting block; 36. Restricting groove; 37. Valve seat; 4. Collection bag; 5. Air inlet pipe. Detailed Implementation

[0023] Example: Reference Figures 1 to 4 This utility model provides a quick replacement valve for an anti-adsorption gas sampling bag, which aims to solve the structural defects in the prior art where the gas sampling bag connection is easy to fall off, the valve replacement operation is cumbersome, and it is difficult to meet the high cleanliness anti-adsorption requirements.

[0024] like Figure 1 and Figure 2 As shown, the rapid replacement valve for the anti-adsorption gas sampling bag includes a valve body 1, an air inlet pipe 5 connected to one end of the valve body 1, and a collection bag 4 connected to the other end of the valve body 1. The valve body 1 is the core component of the gas path control, used to control the gas flow and adjust the flow rate. The air inlet pipe 5 is used to introduce external gas, and the collection bag 4 is used to store the collected gas samples.

[0025] To prevent the intake pipe 5 from accidentally falling off during operation and to ensure airtightness, a snap-fit ​​mechanism 2 is provided at the connection between the intake pipe 5 and the valve body 1. The snap-fit ​​mechanism 2 adopts a split docking structure, including an outer pipe 1 21 fixedly connected to the valve body 1 and an outer pipe 27 fixedly connected to the intake pipe 5. The outer pipe 1 21 and the outer pipe 27 are detachably fixedly connected by a limiting component 29. The design makes the pipe connection more stable and easier to maintain.

[0026] Specific reference Figure 2 and Figure 3 The outer tube 21 is equipped with a connecting rod 22, which supports the internal sealing assembly. The connecting rod 22 is threaded to the inside of the outer tube 21 via an external thread. A spring 23 is fixedly connected to the end of the connecting rod 22 away from the valve body 1. The spring 23 is used to provide a reset force. A sealing ball 24 is fixedly connected to the other end of the spring 23. In its natural state, the sealing ball 24 is used to block the gas passage to prevent gas leakage. A push column 25 is fixedly connected to the top of the sealing ball 24. The push column 25 is used to transmit thrust to push open the sealing ball 24 during connection.

[0027] A connecting rod 28 is provided inside the outer tube 27. One end of the connecting rod 28 is fixedly connected to the air inlet pipe 5. The connecting rod 28 is connected to the inside of the outer tube 27 through an external thread. The other end of the outer tube 27 is fixedly connected to a limiting ring 26. The limiting ring 26 is used to limit the position of the connecting rod 28 and assist in sealing. When the outer tube 1 21 and the outer tube 27 are connected, the pusher 25 extends into the outside tube 27 and abuts against the end face of the connecting rod 28 to push the sealing ball 24 into the outer tube 1 21, thereby opening the air passage.

[0028] The limiting component 29 located at the external connection of the two pipes includes a limiting ring 291 and a thread 292 provided on the inner wall of the limiting ring 291. The limiting ring 291 is sleeved on the outside of the outer pipe 21 or the outer pipe 27, and is simultaneously threaded with the outer wall threads of the outer pipe 21 and the outer pipe 27 by the thread 292, thereby locking the two pipes together.

[0029] In addition, to meet the requirements for anti-adsorption sampling, the components in contact with the gas in the valve body 1, the air inlet pipe 5, the clamping mechanism 2, and the inner surface of the collection bag 4 are all made of anti-adsorption materials such as polyvinylidene fluoride, to ensure that the gas sample is not adsorbed or contaminated by the pipe wall during transmission.

[0030] Reference Figure 2 and Figure 4 The quick-release mechanism 3 includes a connecting block 31 and a valve seat 37. The connecting block 31 is fixedly connected to the end of the valve body 1 away from the air inlet pipe 5, serving as the main mounting base of the quick-release mechanism 3. The valve seat 37 is fixedly connected to the opening of the collection bag 4. An annular limiting groove 36 is provided on the outside of the valve seat 37 along the circumferential direction. The limiting groove 36 is used to provide a snap-fit ​​positioning space.

[0031] A channel for gas flow is provided at the center of the end face of the connecting block 31 away from the valve body 1. A connecting ring 32 is rotatably connected to the outer circumference of the connecting block 31. The connecting ring 32 is used to provide the power for driving and locking. The inner wall of the connecting ring 32 is provided with thread 2 33. At the same time, multiple shrink blocks 34 are slidably connected inside the connecting ring 32. The shrink blocks 34 are circumferentially distributed, and their outer walls are provided with protrusions or threaded structures that are compatible with thread 2 33.

[0032] At the same time, a limiting block 35 is fixedly connected to the end of each shrink block 34 away from the connecting block 31. The limiting block 35 protrudes from the inner surface of the shrink block 34, and the cross-sectional shape of the limiting block 35 is adapted to the shape of the limiting groove 36.

[0033] In the assembled state, when it is necessary to fix the valve body 1, align the quick release mechanism 3 with the valve seat 37 and rotate the connecting ring 32 clockwise. The connecting ring 32 uses the guiding effect of the thread 2 33 to drive multiple shrink blocks 34 to shrink and gather radially inward, so that the limiting block 35 at the end of the shrink block 34 is tightly locked into the limiting groove 36 outside the valve seat 37, thereby firmly locking the valve body 1 onto the collection bag 4 and ensuring the mechanical strength and airtightness of the connection.

[0034] When valve body 1 needs to be disassembled or replaced, the connecting ring 32 is rotated in the opposite direction. The thread 33 no longer applies radial pressure to the shrink block 34. The shrink block 34 expands outward and resets, driving the limiting block 35 to disengage from the limiting groove 36. This allows for easy separation of valve body 1 from collection bag 4. This quick-release structure, which uses rotation to drive the claws to shrink, greatly improves replacement efficiency.

[0035] As a preferred embodiment, to ensure automatic airflow during external pipe connection and automatic sealing during disconnection, please refer again... Figure 3 The connecting rod 22, which is internally threaded to the outer tube 21, is preferably a hollow tubular structure or has a ventilation channel on its outer periphery. The connecting rod 22 is not only used to fix the spring 23, but also serves as a guide for airflow. The spring 23 is preferably a corrosion-resistant stainless steel spring or a spring with an anti-adsorption coating on its surface. The outer diameter of the sealing ball 24 is larger than the flow port diameter inside the outer tube 21. Under normal conditions, the spring 23 pushes the sealing ball 24 to fit tightly against the sealing surface of the inner wall of the outer tube 21, forming a normally closed state.

[0036] In another preferred embodiment, in order to achieve the action of pushing open the sealing ball 24, the connecting rod 28 inside the outer tube 27 is designed to have a specific axial length. When the outer tube 1 21 is connected to the outer tube 27 and locked by the limiting component 29, the pusher 25 extends into the outer tube 27 and abuts against the end face of the connecting rod 28. As the outer tube 1 21 and the outer tube 27 are further tightened, the connecting rod 28 forces the pusher 25 to retract, thereby pushing open the sealing ball 24 and opening the air passage. The structure uses the mechanical connection process to complete the opening of the air passage simultaneously without additional operation.

[0037] In a preferred embodiment, to improve the reliability and sealing of the connection, the limiting ring 291 in the limiting assembly 29 is designed as a sleeve-shaped structure. The limiting ring 291 spans the mating gap between the outer tube 1 21 and the outer tube 27. The thread 292 engages with the external threads at the ends of the outer tube 1 21 and the outer tube 27 respectively. By rotating the limiting ring 291, an axial tensile force can be generated to tightly press the end faces of the outer tube 1 21 and the outer tube 27 together to prevent gas from leaking from the mating gap.

[0038] As another preferred embodiment, in order to adapt to sampling bag interfaces of different sizes and improve versatility, the shrink block 34 in the quick-release mechanism 3 is made of elastic material, or an auxiliary spring is provided between the shrink block 34 and the connecting ring 32 so that when the connecting ring 32 is rotated in the opposite direction to loosen, the shrink block 34 can automatically open outward by its own elasticity or auxiliary elastic force, so that the limiting block 35 can smoothly disengage from the limiting groove 36 and achieve rapid separation.

[0039] As a preferred embodiment, in order to further optimize the anti-adsorption performance, the inner wall of the vent hole opened at the center of the end face of the connecting block 31 away from the valve body 1, as well as the surfaces of the push column 25 and the sealing ball 24, are all polished or coated with polytetrafluoroethylene to minimize the adsorption residue of active gas and ensure sampling accuracy.

[0040] The working principle is as follows: When using the intake pipe 5 for gas sampling connection, first align the outer tube 27 at the end of the intake pipe 5 with the outer tube 21 at the end of the valve body 1, and then rotate the limiting ring 291 in the limiting assembly 29.

[0041] As the limiting ring 291 gradually tightens under the action of the thread 292, the outer tube 21 and the outer tube 27 approach each other and press together. During this process, the end face of the connecting rod 28 presses against the extended push column 25, pushing the push column 25 together with the sealing ball 24 to move into the valve body 1.

[0042] The sealing ball 24 overcomes the resistance of the spring 23 and leaves the sealing position on the inner wall of the outer tube 21, thereby opening the air passage. External gas can then smoothly enter the valve body 1 through the gap between the inlet pipe 5, the connecting rod 28 and the outer tube 27, the opened sealing ball 24, and the gap between the connecting rod 22 and the outer tube 21. The connection process is secured by the threaded self-locking, preventing the inlet pipe 5 from accidentally falling off.

[0043] When it is necessary to install the valve body 1 onto the collection bag 4, the connecting ring 32 in the quick-release mechanism 3 is fitted around the valve seat 37 of the collection bag 4, and the connecting ring 32 is rotated clockwise.

[0044] The thread 33 inside the connecting ring 32 engages with the thread or protrusion on the outer wall of the shrink block 34, driving the shrink block 34 to shrink and converge radially inward, so that the limiting block 35 at the end of the shrink block 34 is accurately engaged in the limiting groove 36 on the outer wall of the valve seat 37, thereby achieving mechanical locking and sealing connection between the valve body 1 and the collection bag 4.

[0045] When sampling is completed or valve replacement is required, simply rotate the limiting ring 291 in the reverse direction to loosen the outer tube 21 and the outer tube 27. At this time, the spring 23 pushes the sealing ball 24 to reset, automatically sealing the gas path of the valve body 1 to prevent internal gas leakage. Similarly, rotating the connecting ring 32 in the reverse direction causes the contraction block 34 to expand outward, and the limiting block 35 to disengage from the limiting groove 36, allowing the valve body 1 to be quickly removed. The entire operation process does not require additional tools, greatly improving the replacement efficiency of on-site sampling.

Claims

1. A quick replacement valve for an anti-adsorption gas sampling bag, comprising: The valve body (1) and the air inlet pipe (5) are connected to one end of the valve body (1), and the valve body (1) also includes a collection bag (4) connected to the other end of the valve body (1); Its features are, A snap-fit ​​mechanism (2) is provided at the connection between the air intake pipe (5) and the valve body (1). The snap-fit ​​mechanism (2) includes an outer tube one (21) fixedly connected to the valve body (1) and an outer tube two (27) fixedly connected to the air intake pipe (5). The inner thread of the outer tube one (21) is connected to a connecting rod one (22). The end of the connecting rod one (22) is fixedly connected to a spring (23). The other end of the spring (23) is fixedly connected to a sealing ball (24). The side of the sealing ball (24) away from the spring (23) is fixedly connected to a push column (25). The inner thread of the outer tube two (27) is fixedly connected to a connecting rod two (28). A limiting component (29) is sleeved on the outside of the outer tube one (21) and the outer tube two (27). The outer tube one (21) and the outer tube two (27) are fixedly connected by the limiting component (29). A quick-release mechanism (3) is provided at the connection between the valve body (1) and the collection bag (4). The quick-release mechanism (3) includes a connecting block (31) fixedly connected to the valve body (1) and a valve seat (37) fixedly connected to the collection bag (4). A limiting groove (36) is provided on the outer wall of the valve seat (37). A connecting ring (32) is rotatably connected to the connecting block (31). Multiple shrink blocks (34) are slidably connected inside the connecting ring (32). The shrink blocks (34) extend to the valve seat (37) and are engaged in the limiting groove (36).

2. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 1, characterized in that, The sealing ball (24) is slidably fitted to the inner wall of the outer tube one (21), and the pusher (25) extends along the axial direction of the outer tube one (21). When the outer tube one (21) is connected to the outer tube two (27), the pusher (25) extends into the outer tube two (27) and abuts against the end face of the connecting rod two (28). The sealing ball (24) is in the open state of compressing the spring (23).

3. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 1, characterized in that, A limiting ring (26) is fixedly connected to the end of the outer tube two (27) away from the air inlet pipe (5). The limiting ring (26) is sleeved on the outer periphery of the connecting rod two (28), and the connecting rod two (28) is threaded to the inner wall of the outer tube two (27) through external threads.

4. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 1, characterized in that, The limiting component (29) includes a limiting ring (291) and a threaded first (292) disposed on the inner wall of the limiting ring (291). The limiting ring (291) is connected across the joint between the outer tube one (21) and the outer tube two (27), and the limiting ring (291) is threadedly fastened to the outer wall of the outer tube one (21) and the outer wall of the outer tube two (27) respectively through the threaded first (292).

5. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 1, characterized in that, The inner wall of the connecting ring (32) is provided with thread two (33), and the outer wall of the shrink block (34) is provided with a protrusion or thread structure that matches the thread two (33). When the connecting ring (32) rotates relative to the connecting block (31), the thread two (33) drives multiple shrink blocks (34) to converge radially inward.

6. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 5, characterized in that, Each of the contraction blocks (34) is fixedly connected to a limiting block (35) at one end away from the connecting block (31). The limiting block (35) protrudes from the inner surface of the contraction block (34), and the shape of the limiting block (35) is adapted to the cross-sectional shape of the limiting groove (36).

7. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 6, characterized in that, The limiting groove (36) is opened along the circumference of the valve seat (37). When the limiting block (35) is inserted into the limiting groove (36), the axial position of the valve body (1) is locked.

8. The rapid replacement valve for an anti-adsorption gas sampling bag according to claim 1, characterized in that, The inner surfaces of the valve body (1), the air inlet pipe (5), the first connecting rod (22), the second connecting rod (28), and the collection bag (4) are all made of polyvinylidene fluoride anti-adsorption material.

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