Sample transmission tube fixing support for headspace sampler

Abstract

The utility model relates to the field of headspace sample injector sample transmission pipe, especially a kind of sample transmission pipe fixing support for headspace sample injector, including fixed base;Still including lifting rod one, the upper end of fixed base is slidably connected with lifting rod one, the upper end of lifting rod one is fixedly connected with fixed frame one, the inside of fixed frame one is fixedly connected with lower clamping plate, the inside of fixed frame one is movably connected with upper clamping plate, the upper end of fixed frame one is screw-connected with bolt one, and the bottom of bolt one is rotatably connected with upper clamping plate;The utility model will transmit the cooperation of upper clamping plate and lower clamping plate and fix the middle section of transmission pipe, left clamping plate and right clamping plate clamp transmission pipe tail end simultaneously, finally, headspace needle is vertically inserted into chromatograph specified position, the middle sag phenomenon caused by transmission pipe dead weight is eliminated by double clamping mechanism, prevent transmission pipe two ends from deviating due to traction, ensure that headspace needle is always with vertical angle accurate docking chromatograph sample inlet.

Description

Technical Field

[0001] This utility model relates to the field of headspace sample transfer tubes, and in particular to a sample transfer tube fixing bracket for headspace samplers. Background Technology

[0002] The headspace sampler transfer tube is a key component connecting the headspace sample vial to the gas chromatograph. It is usually made of inert material, with high temperature resistance and chemical inertness, ensuring that the sample vapor is not adsorbed or decomposed during the transfer process. Its inner diameter is narrow to reduce diffusion effects, and its length is usually long enough to be equipped with a heating function to prevent the condensation of high-boiling-point components. Some models adopt a double-layer structure design, with the outer layer carrying carrier gas to maintain pressure balance and the inner layer transferring volatile components. The end is often equipped with a switching valve or cold trap device to focus the sample and achieve analysis with low detection limits.

[0003] The transfer tube itself is not equipped with a separate fixing device. Due to the weight of the transfer tube itself, both ends of the transfer tube are pulled towards the unfixed middle. This causes the fixing nut of the transfer tube to the chromatograph inlet to shift towards the side where the headspace sampler is located. As a result, it is difficult to insert the injection needle at the end of the transfer tube into the chromatograph inlet at a vertical angle, which makes installation difficult. The pulling effect also affects the connection between the inner nut fixing the end of the transfer tube and the outer thread of the chromatograph inlet. Because the threads cannot be completely matched, the connection is not tight. During the replacement of the injection needle, it will accelerate the wear of the threads of the chromatograph inlet, causing the carrier gas at the chromatograph inlet to leak. Ultimately, the pressure at the instrument inlet cannot reach the set value, and the gas chromatograph cannot operate normally.

[0004] Therefore, since the aforementioned transfer tube itself does not have a separate fixing device, the weight of the transfer tube itself will pull the two ends of the transfer tube towards the unfixed middle, causing the fixing nut of the transfer tube connected to the chromatograph inlet to be shifted to the side where the headspace sampler is located due to the weight pull. This makes it difficult for the injection needle at the end of the transfer tube to be inserted into the chromatograph inlet at a vertical angle, causing difficulties in installation. Therefore, a sample transfer tube fixing bracket for headspace sampler was designed. Utility Model Content

[0005] To overcome the problem that the transfer tube itself does not have a separate fixing device, the weight of the transfer tube will pull both ends of the transfer tube towards the unfixed middle, causing the fixing nut of the transfer tube to the chromatograph inlet to be offset by the weight towards the side where the headspace sampler is located. This makes it difficult for the injection needle at the end of the transfer tube to be inserted into the chromatograph inlet at a vertical angle, causing installation difficulties.

[0006] The technical solution of this utility model is as follows: a sample transfer tube fixing bracket for a headspace sampler, including a fixing base; and a lifting rod, the lifting rod being slidably connected to the upper end of the fixing base, the upper end of the lifting rod being fixedly connected to a fixing frame, a lower clamping plate being fixedly connected inside the fixing frame, an upper clamping plate being movably connected inside the fixing frame, a bolt being threadedly connected to the upper end of the fixing frame, the bottom of the bolt being rotatably connected to the upper clamping plate, an outer frame being fixedly connected to the upper end of the fixing base, a gear being rotatably connected inside the outer frame, and a locking block being rotatably connected inside the outer frame. The gear meshes with the locking block and the gear meshes with the lifting rod. The left end of the gear is fixedly connected to the throttle handle. The right end of the locking block is fixedly connected to the rotating block. The top of the locking block is fixedly connected to the spring. The spring is fixedly connected to the outer frame. The rear end of the lifting rod is fixedly connected to two fixed rods. The right end of the fixed rod is slidably connected to the telescopic rod. The right end of the telescopic rod is fixedly connected to the fixed frame. The inside of the fixed frame is fixedly connected to the left clamping plate. The inside of the fixed frame is movably connected to the right clamping plate. The right end of the fixed frame is threadedly connected to the bolt. The bottom of the bolt is rotatably connected to the right clamping plate.

[0007] Preferably, after the transfer tube passes through the first and second fixed frames in sequence, the upper and right clamping plates are moved by rotating the first and second bolts respectively, so that the upper and lower clamping plates cooperate to fix the middle section of the transfer tube, while the left and right clamping plates clamp the tail end of the transfer tube. The two fixed frames ensure that the headspace needle of the transfer tube is perpendicular to the chromatograph. Then, the telescopic rod is pulled and slid along the fixed rod to make the headspace needle accurately aligned with the slot of the chromatograph. Then, the rotating block is rotated simultaneously to release the locking of the locking block on the gear. The lifting rod is lowered by the gear transmission, and finally the headspace needle is vertically inserted into the designated position of the chromatograph. The double clamping mechanism eliminates the phenomenon of the middle sagging caused by the weight of the transfer tube and prevents the two ends of the transfer tube from deviating due to traction force. It ensures that the headspace needle is always accurately aligned with the chromatograph inlet at a vertical angle, avoiding the problem of injection needle deflection caused by the lack of a dedicated fixing device in traditional installation.

[0008] Preferably, the telescopic rod has a sliding connection to a lifting rod II inside, and the lower telescopic rod has a rotatable connection to a ratchet inside.

[0009] Preferably, the ratchet and the lifting rod are engaged, and the telescopic rod has an insert block inside for rotational connection.

[0010] Preferably, the insert block is engaged with a ratchet, and a spring is rotatably connected to the bottom of the insert block.

[0011] Preferably, the second spring is fixedly connected to the telescopic rod, and the front end of the insert block is fixedly connected to the second throttle.

[0012] Preferably, a support frame is fixedly connected to the bottom of the telescopic rod, and four suction cups are fixedly connected to the bottom of the support frame.

[0013] Preferably, the bottom of the fixed base is fixedly connected to four casters, the inside of the fixed base is rotatably connected to a brake plate, and the inside of the fixed base is provided with four protrusions, with the brake plate movably connected to the protrusions.

[0014] The beneficial effects of this utility model are:

[0015] After the transfer tube passes through fixed frame one and fixed frame two in sequence, rotating bolt one and bolt two respectively moves the upper clamping plate and the right clamping plate, so that the upper clamping plate and the lower clamping plate cooperate to fix the middle section of the transfer tube, while the left clamping plate and the right clamping plate clamp the tail end of the transfer tube. The two fixed frames two ensure that the headspace needle of the transfer tube is perpendicular to the chromatograph. Then, the telescopic rod is pulled and slid along the fixed rod to make the headspace needle accurately aligned with the slot of the chromatograph. Then, the rotating block is rotated simultaneously to release the locking block on the gear. The lifting rod one is lowered by the gear transmission, and finally the headspace needle is vertically inserted into the designated position of the chromatograph. The double clamping mechanism eliminates the phenomenon of the middle sagging caused by the weight of the transfer tube and prevents the two ends of the transfer tube from deviating due to traction force. It ensures that the headspace needle is always accurately aligned with the chromatograph inlet at a vertical angle, avoiding the problem of injection needle deflection caused by the lack of a dedicated fixing device in traditional installation. Attached Figure Description

[0016] Figure 1 The diagram shown is a three-dimensional structural schematic of this utility model;

[0017] Figure 2 The diagram shown is a three-dimensional rear cross-sectional view of the present invention.

[0018] Figure 3 The diagram shown is a three-dimensional side sectional view of the present invention.

[0019] Figure 4 The diagram shown is a three-dimensional left cross-sectional view of this utility model.

[0020] Figure 5 The diagram shown is a three-dimensional side sectional view of the universal wheel of this utility model.

[0021] Explanation of reference numerals in the attached diagram: 1. Fixed base; 2. Lifting rod one; 3. Fixed frame one; 4. Upper clamping plate; 5. Lower clamping plate; 6. Bolt one; 7. Outer frame; 8. Gear; 9. Locking block; 10. Spring one; 11. Turning handle one; 12. Fixed rod; 13. Telescopic rod; 14. Fixed frame two; 15. Left clamping plate; 16. Right clamping plate; 17. Bolt two; 18. Lifting rod two; 19. Ratchet; 20. Insert block; 21. Spring two; 22. Turning handle two; 23. Support frame; 24. Suction cup; 25. Universal wheel; 26. Brake plate; 27. Protrusion; 28. Rotating block. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] Headspace autosamplers play a crucial role in gas chromatography analysis. They efficiently deliver gas samples to the analytical equipment through a transfer tube wrapped in insulating material. However, due to the lack of effective fixed support for the transfer tube itself, its weight will naturally sag, causing the two ends to converge towards the middle. This results in a continuous traction force on the injection port. This mechanical stress not only accelerates the wear of the injection port threads but may also cause problems such as poor sealing and gas leakage, seriously affecting the accuracy of analytical data and the long-term stability of the instrument, while also increasing maintenance costs.

[0024] To address this technical pain point, existing solutions offer various support structures, but they generally suffer from problems such as large size, inconvenient adjustment, and limited fixation effect. For example, while worm gear adjustable supports can adjust the height, they are cumbersome to operate; telescopic rod clamping solutions are difficult to adapt to different experimental scenarios due to limited range of motion; and designs that are directly fixed to the top of the gas chromatograph cannot completely eliminate the influence of traction force because the transfer tube needs to maintain a certain degree of freedom. Based on this, the present invention proposes a lightweight, modular, and highly flexible transfer tube auxiliary fixation device. Its core design concept is to effectively distribute the mechanical load of the transfer tube while ensuring smooth gas flow through a combination of local reinforcement support and dynamic balance. Specifically, the device features an adjustable elastic clamping mechanism in the transfer tube section near the injection port. This mechanism combines high-elasticity silicone or spring steel with a rigid support, providing sufficient support to counteract sagging while absorbing minor displacements caused by instrument vibration or temperature changes through material flexibility, thus avoiding static loads on the injection port. Furthermore, the device employs a magnetic or snap-on quick-release mechanism instead of traditional bolt fixing, allowing maintenance personnel to install, remove, or adjust the support with one hand, significantly improving the efficiency of replacing injection needles or septa. Crucially, these designs fail to fully consider the special requirements of headspace injection—the transfer tube needs to maintain a certain degree of flexibility to accommodate length changes caused by temperature variations, while simultaneously avoiding excessive shaking that could affect injection accuracy.

[0025] The entire transfer tube system is divided into three functional sections for separate processing: the initial section near the headspace sampler is semi-rigidly fixed to ensure the stability of the initial position; the middle section is equipped with sliding support points to allow for length changes due to thermal expansion and contraction. Specifically, the main support frame of the device uses an aerospace-grade aluminum alloy frame, and effective weight reduction is achieved through optimized topology; medical-grade silicone pads are used at the contact points to ensure clamping force while avoiding damage to the insulation layer; the unique quick-release mechanism uses a composite design of neodymium iron boron permanent magnets and mechanical clips, requiring only 5N of operating force to complete installation or disassembly, significantly improving efficiency compared to traditional bolt connections. In laboratory comparative tests, this device reduced vibration amplitude at the inlet connection point, decreased thread wear rate, and shortened maintenance time.

[0026] In terms of space optimization, the device is suitable for modern laboratory environments with limited space. Its modular structure can be adapted to insulated transfer tubes of different diameters and is compatible with headspace samplers and gas chromatographs from mainstream brands, demonstrating high versatility. From a technical perspective, the main body of the device can be made of PEEK engineering plastics or aluminum alloys using 3D printing or injection molding processes, ensuring chemical corrosion resistance while controlling costs. In the future, tension sensors and intelligent feedback systems can be further integrated to achieve automatic dynamic adjustment of clamping force, promoting the development of analytical processes towards a higher level of automation.

[0027] In summary, this invention, through the deep integration of structural innovation and human-centered design, not only effectively solves the problems of inlet wear and leakage caused by the traction of the transfer tube, but also improves the operation and maintenance experience with its lightweight and simple design, providing a reliable guarantee for the long-term stable operation of headspace sampling technology. It has significant market application value and industry promotion potential.

[0028] From an engineering application perspective, this design fully considers the diversity of practical usage scenarios: the support height can be steplessly adjusted from 50-150mm via a gas spring, adapting to different instrument combinations; ensuring compatibility with various sample introduction directions; and the modular design allows users to select additional functions according to actual needs, such as a temperature monitoring module or an automatic tension adjustment system. In terms of reliability, all metal parts are anodized, and key moving parts use self-lubricating bearings, ensuring long-term stable operation in corrosive laboratory environments.

[0029] Future technological evolution directions include: developing intelligent sensing versions to monitor the stress state of transmission tubes in real time through embedded strain gauges; exploring the application of shape memory alloys in automatic adjustment mechanisms; and researching automatic alignment systems based on machine vision. These innovations will further enhance the automation and intelligence of the device, providing key technical support for the transformation of analytical laboratories into "smart laboratories".

[0030] Please see Figures 1-5 This utility model provides an embodiment: a sample transfer tube fixing bracket for a headspace sampler includes a fixing base 1; it also includes a lifting rod 2, the upper end of the fixing base 1 is slidably connected to the lifting rod 2, the upper end of the lifting rod 2 is fixedly connected to a fixing frame 3, the interior of the fixing frame 3 is fixedly connected to a lower clamping plate 5, the interior of the fixing frame 3 is movably connected to an upper clamping plate 4, the upper end of the fixing frame 3 is threadedly connected to a bolt 6, the bottom of the bolt 6 is rotatably connected to the upper clamping plate 4, the upper end of the fixing base 1 is fixedly connected to an outer frame 7, and the interior of the outer frame 7 is rotatably connected to the upper frame 4. A gear 8 is connected to the outer frame 7, and a locking block 9 is rotatably connected inside the outer frame 7. The gear 8 meshes with the locking block 9 and the lifting rod 2. A throttle 11 is fixedly connected to the left end of the gear 8, and a rotating block 28 is fixedly connected to the right end of the locking block 9. A spring 10 is fixedly connected to the top of the locking block 9 and is fixedly connected to the outer frame 7. Two fixing rods 12 are fixedly connected to the rear end of the lifting rod 2. A telescopic rod 13 is slidably connected to the right end of the fixing rod 12, and a fixing frame 14 is fixedly connected to the right end of the telescopic rod 13. The interior of the fixing frame 14 is fixed. A left clamping plate 15 is connected to a right clamping plate 16, which is movably connected inside a second fixing frame 14. A bolt 17 is threaded onto the right end of the second fixing frame 14, and the bottom of bolt 17 is rotatably connected to the right clamping plate 16. After the transfer tube passes through the first fixing frame 3 and the second fixing frame 14 in sequence, rotating bolts 16 and 17 respectively moves the upper clamping plate 4 and the right clamping plate 16, causing the upper clamping plate 4 and the lower clamping plate 5 to cooperate in fixing the middle section of the transfer tube. Simultaneously, the left clamping plate 15 and the right clamping plate 16 clamp the tail end of the transfer tube. The two second fixing frames 14 ensure that the transfer tube head syringe is aligned with the chromatograph. The instrument remains vertical. Then, the telescopic rod 13 is pulled and slid along the fixed rod 12 to precisely align the headspace needle with the chromatograph slot. Simultaneously, the rotating block 28 is rotated to release the locking block 9 on the gear 8. The gear 8 is used to drive the lifting rod 2 to descend, and finally the headspace needle is vertically inserted into the designated position of the chromatograph. The double clamping mechanism eliminates the phenomenon of drooping in the middle caused by the weight of the transfer tube, and prevents the two ends of the transfer tube from shifting due to traction force. This ensures that the headspace needle is always precisely aligned with the chromatograph inlet at a vertical angle, avoiding the problem of needle skew caused by the lack of a dedicated fixing device in traditional installations.

[0031] Please see Figures 2-4In this embodiment, a lifting rod 18 is slidably connected inside the telescopic rod 13, and a ratchet 19 is rotatably connected inside the lower telescopic rod 13. The lifting rod 18 slides up and down inside the telescopic rod 13. When the lifting rod 18 moves, it drives the ratchet 19 to rotate. The ratchet 19 is engaged with the lifting rod 18. A plug block 20 is rotatably connected inside the telescopic rod 13. When the lifting rod 18 moves downward on the telescopic rod 13, the ratchet 19 is blocked by the plug block 20 and cannot rotate, so the lifting rod 18 cannot move downward. When it is necessary for the lifting rod to move upward, the handle 22 is turned to make the plug block 20 rotate. The plug block 20 is engaged with the ratchet 19. A spring 21 is rotatably connected to the bottom of the plug block 20. Then, when the ratchet 19 can rotate, the lifting rod 18 moves downward. Then, the spring drives the plug block 20 to reset and restrict the rotation of the ratchet 19.

[0032] Please see Figures 3-5 In this embodiment, spring 21 is fixedly connected to telescopic rod 13, and throttle 22 is fixedly connected to the front end of plug 20. Support frame 23 is fixedly connected to the bottom of telescopic rod 13, and four suction cups 24 are fixedly connected to the bottom of support frame 23. Lifting rod 28 moves to fix the suction cups 24 at the bottom of support frame 23 to the chromatograph, aligning the position of the transfer tube with the detection port on the chromatograph and fixing it to prevent displacement. Four casters 25 are fixedly connected to the bottom of fixed base 1. Brake plate 26 is rotatably connected inside fixed base 1. Four protrusions 27 are provided inside fixed base 1. Brake plate 26 is movably connected to protrusions 27, pushing fixed base 1 to move through casters 25. When it moves to the appropriate position, brake plate 26 is rotated to make brake pad contact casters 25, fixing the position of fixed base 1. Protrusions 27 can assist in fixing the position of brake plate 26.

[0033] During operation, the fixed base 1 is moved via the casters 25. When it reaches the appropriate position, the brake plate 26 is rotated to make the brake pads contact the casters 25, fixing the position of the fixed base 1. The protrusion 27 can assist in fixing the position of the brake plate 26. The transfer tube is passed through the first fixed frame 3 and the second fixed frame 14. Then, the first bolt 6 and the second bolt 17 are rotated to move the upper clamping plate 4 and the right clamping plate 16. The upper clamping plate 4 and the lower clamping plate 5 fix the middle section of the transfer tube, and the left clamping plate 15 and the right clamping plate 16 fix the tail end of the transfer tube. The two second fixed frames 14 ensure that the headspace needle on the transfer tube is perpendicular to the chromatograph. The telescopic rod 13 is pulled on the fixed rod 1. 2. Slide the headspace needle inward to align it perpendicularly with the slot on the chromatograph. Then, rotate the second handle 22 to rotate the insertion block 20, releasing the lock on the ratchet 19. Push the second lifting rod 18 downward within the telescopic rod 13 to fix the suction cup 24 at the bottom of the support frame 23 onto the chromatograph, securing the transfer tube to prevent displacement. Then, the spring drives the insertion block 20 to reset and restrict the rotation of the ratchet 19. Finally, rotate the rotating block 28 to release the lock on the gear 8 from the locking block 9. At the same time, rotate the first handle 11 to rotate the gear 8. The gear 8 drives the first lifting rod 2 to move downward, while the second lifting rod 18 slides upward on the telescopic rod 13, allowing the headspace needle on the transfer tube to insert into the corresponding position.

[0034] Through the above steps, the transfer tube is passed through the fixing frame 1 (3) and fixing frame 2 (14). Then, the bolts 1 (6) and 2 (17) are rotated, which moves the upper clamping plate 4 and the right clamping plate 16. The upper clamping plate 4 and the lower clamping plate 5 fix the middle section of the transfer tube, and the left clamping plate 15 and the right clamping plate 16 fix the tail end of the transfer tube. The two fixing frames 2 (14) ensure that the headspace needle on the transfer tube is perpendicular to the chromatograph. The telescopic rod 13 is pulled and slids inside the fixing rod 12 so that the headspace needle is perpendicular to the slot on the chromatograph. The rotating block 28 is rotated so that the locking block 9 releases the lock on the gear 8. At the same time, the gear 8 drives the lifting rod 1 (2) to move downward so that the headspace needle on the transfer tube is inserted into the corresponding position. This solves the problem that the transfer tube itself does not have a separate fixing device. Due to the weight of the transfer tube itself, the two ends of the transfer tube will be pulled towards the unfixed middle. This causes the fixing nut of the transfer tube connected to the chromatograph inlet to be shifted to the side where the headspace sampler is located due to the weight pull, making it difficult for the injection needle at the end of the transfer tube to be inserted into the chromatograph inlet at a vertical angle, which makes the installation difficult.

Claims

1. A sample transfer tube fixing bracket for a headspace sampler, comprising a fixing base (1); characterized in that: It also includes a lifting rod (2), the upper end of the fixed base (1) is slidably connected to the lifting rod (2), the upper end of the lifting rod (2) is fixedly connected to the fixed frame (3), the lower clamping plate (5) is fixedly connected inside the fixed frame (3), the upper clamping plate (4) is movably connected inside the fixed frame (3), the upper end of the fixed frame (3) is threadedly connected to the bolt (6), the bottom of the bolt (6) is rotatably connected to the upper clamping plate (4), the upper end of the fixed base (1) is fixedly connected to the outer frame (7), the inner part of the outer frame (7) is rotatably connected to the gear (8), the inner part of the outer frame (7) is rotatably connected to the locking block (9), the gear (8) and the locking block (9) are meshed, the gear (8) and the lifting rod (2) are meshed, the gear (8) The left end of the lifting rod (2) is fixedly connected to a throttle (11), the right end of the locking block (9) is fixedly connected to a rotating block (28), the top of the locking block (9) is fixedly connected to a spring (10), the spring (10) is fixedly connected to the outer frame (7), the rear end of the lifting rod (2) is fixedly connected to two fixed rods (12), the right end of the fixed rod (12) is slidably connected to a telescopic rod (13), the right end of the telescopic rod (13) is fixedly connected to a fixed frame (14), the inside of the fixed frame (14) is fixedly connected to a left clamping plate (15), the inside of the fixed frame (14) is movably connected to a right clamping plate (16), the right end of the fixed frame (14) is threadedly connected to a bolt (17), the bottom of the bolt (17) is rotatably connected to the right clamping plate (16).

2. The sample transfer tube fixing bracket for a headspace sampler according to claim 1, characterized in that: The telescopic rod (13) is internally slidably connected to a lifting rod (18), and the lower telescopic rod (13) is internally rotatably connected to a ratchet (19).

3. The sample transfer tube fixing bracket for a headspace sampler according to claim 2, characterized in that: The ratchet (19) is engaged with the lifting rod (18), and the telescopic rod (13) is internally connected to the insert (20).

4. A sample transfer tube fixing bracket for a headspace sampler according to claim 3, characterized in that: The insert (20) is engaged with the ratchet (19), and the bottom of the insert (20) is rotatably connected to the second spring (21).

5. A sample transfer tube fixing bracket for a headspace sampler according to claim 4, characterized in that: Spring 2 (21) is fixedly connected to telescopic rod (13), and throttle 2 (22) is fixedly connected to the front end of plug (20).

6. A sample transfer tube fixing bracket for a headspace sampler according to claim 3, characterized in that: The bottom of the telescopic rod (13) is fixedly connected to a support frame (23), and the bottom of the support frame (23) is fixedly connected to four suction cups (24).

7. A sample transfer tube fixing bracket for a headspace sampler according to claim 6, characterized in that: The bottom of the fixed base (1) is fixedly connected with four casters (25), and the inside of the fixed base (1) is rotatably connected with a brake plate (26). The inside of the fixed base (1) is provided with four protrusions (27), and the brake plate (26) is movably connected with the protrusions (27).

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