Rapid avoidance type gas chromatography-mass spectrometry transmission line

Abstract

The utility model provides a rapid avoiding type gas chromatography-mass spectrometry transmission line which comprises a heat preservation head, a sliding block, a sliding cylinder, fixing sleeves, a reset spring and a heat preservation pipe, and the outer side of the heat preservation pipe is sleeved with the fixing sleeves at intervals; the sliding cylinder sleeves the outer side of the thermal insulation pipe, and the rear end of the sliding cylinder is connected with the front end of the fixed sleeve; the heat preservation head is airtight, slidably connected to the outer side of the front end of the heat preservation pipe in a sleeving mode and arranged in the sliding cylinder. One end of the reset spring abuts against the heat preservation head, the other end of the reset spring abuts against the fixing sleeve, and the heat preservation head is pushed forwards to the pressing position. The sliding block is connected with the heat preservation head and partially extends out of the sliding barrel so as to drive the heat preservation head to move backwards to the avoiding position. One of the sliding block and the sliding cylinder is provided with a sliding groove, the other one of the sliding block and the sliding cylinder is provided with a sliding rod clamped into the sliding groove, and the sliding groove comprises a working stroke section corresponding to the pressing position and a positioning section corresponding to the avoiding position. By adopting the structure, the transmission line and the ion source can be quickly dissociated without disassembling hardware, so that the ion source is more convenient to disassemble and assemble.

Description

Technical Field

[0001] The utility model relates to the technical field of mass spectrometers, in particular to a fast avoidance gas chromatography-mass spectrometry transmission line. Background Art

[0002] Gas chromatography-mass spectrometry is a common device for organic matter detection. The transmission line is the key device that connects the two instruments, gas chromatography and mass spectrometry, together. That is, the chromatographic column in the gas chromatography is inserted into the transmission line, and the chromatographic column is introduced into the ion source of the mass spectrometry through the transmission line to achieve joint analysis. Since the two instruments are independent instruments, the internal ambient temperature of the instruments is different, and the gas chromatography is a positive pressure system and the mass spectrometry is a negative pressure system, the transmission line needs to be used as an interface component for material transmission and pressure transition between the gas chromatography and mass spectrometry.

[0003] In order to prevent the analytical sample flow from condensing during transmission in the chromatographic column of the transmission line, resulting in residue and reduced sensitivity, the transmission line needs to maintain a certain high temperature and evenly distribute heat to keep the sample in a gaseous state. At the same time, in order to ensure that the analytes in the chromatographic column are quickly and focusedly transmitted to the mass spectrometer ion source and prevent condensation, the heat-insulating transmission line needs to be extended into and closely attached to the ion source interface of the mass spectrometer. However, when maintaining the mass spectrometer ion source, the transmission line needs to be separated from the ion source in order to disassemble the ion source for maintenance operations.

[0004] There are two traditional ways to dissociate the ion source and the transmission line: one is to install the ion source on the side panel of the vacuum chamber of the mass spectrometer. When dissociating the transmission line, the side panel of the vacuum chamber needs to be opened. This method requires disassembling the vacuum chamber first, which is complicated to operate and will accumulate more air moisture and particulate dust in the vacuum chamber. The second method is to loosen the fixing nut of the transmission line, pull the transmission line in reverse for a distance, and dissociate the two. This method requires frequent disassembly of the sealing nut of the transmission line, resulting in air leakage.

[0005] Therefore, a quick transfer line and ion source dissociation mechanism is needed to achieve convenient operation and maintenance of the gas chromatography-mass spectrometry equipment without dismantling the hardware.

[0006] For example, patent CN218548368U discloses an ion source device for GC-IMS. As described in the article, the ion source device can continuously heat the chromatographic column, but the transmission line is not in contact with the ion source, the heating is limited, and the temperature is low, which still leads to a large temperature difference between the front and rear of the transmission line.

[0007] For example, patent CN115308324A discloses a transmission line, device, temperature-controlled transmission line and method for combining a gas chromatograph and a mass spectrometer, but the transmission line does not have an avoidance function. Utility Model Content

[0008] The main purpose of the utility model is to provide a fast avoidance gas chromatography-mass spectrometry transmission line, which enables the ion source and the transmission line to be quickly dissociated through the avoidance device.

[0009] The secondary purpose of the utility model is to provide a fast avoidance gas chromatography-mass spectrometry transmission line, characterized in that it includes a heat preservation head, a sliding block, a sliding cylinder, a fixed sleeve, a reset spring and a heat preservation tube, wherein:

[0010] The outer side of the insulation tube is sleeved with fixed sleeves at intervals, and the chromatographic column can pass through the insulation tube;

[0011] The sliding tube is sleeved on the outside of the insulation tube, and its rear end is connected to the front end of the fixed sleeve;

[0012] The heat preservation head is airtight and slidably sleeved on the front outer side of the heat preservation pipe and is placed in the slide cylinder;

[0013] One end of the return spring abuts against the heat preservation head, and the other end abuts against the fixed sleeve, so as to push the heat preservation head forward to the compression position under normal conditions;

[0014] The sliding block is connected to the insulation head and partially extends out of the slide cylinder for operation and drives the insulation head to move backward on the insulation tube to a avoidance position; one of the sliding block and the slide cylinder is provided with a slide groove, and the other is provided with a slide rod that is inserted into the slide groove, and the slide groove includes a working stroke section corresponding to the pressing position and a positioning section corresponding to the avoidance position.

[0015] In the fast avoidance gas chromatography-mass spectrometry transmission line, the heat preservation head is integrally mounted with the sliding block by means of a flange at the rear end.

[0016] In the fast avoidance gas chromatography-mass spectrometry transmission line, a sliding rod is radially protruded on each of the two opposite sides of the sliding block, and a sliding groove is provided on each of the two sides of the sliding cylinder.

[0017] The fast avoidance gas chromatography-mass spectrometry transmission line, wherein the rear end of the insulation tube is sealed and connected to the head end of a hollow stud, the rear end of the hollow stud can be used for the chromatographic column to pass through, the hollow stud is also sleeved with the rear end of the fixed sleeve, a hollow structure is formed between the fixed sleeve and the insulation tube, and a heating block is provided on the outside of the fixed sleeve.

[0018] In the fast avoidance gas chromatography-mass spectrometry transmission line, a heating rod and a temperature sensor are installed inside the heating block.

[0019] The fast avoidance gas chromatography-mass spectrometry transmission line is characterized in that a heat insulation pad is installed on the rear end face of the heating block, a heat insulation fiber blanket is wrapped around the outer ring, the shape of the heat insulation fiber blanket is fixed by aluminum foil or copper foil tape, an outer shell is sheathed on the outside of the heat insulation fiber blanket, and the rear end of the shell is connected to the outer peripheral surface of the hollow stud.

[0020] The fast avoidance gas chromatography-mass spectrometry transmission line has a flange welded on a fixed sleeve, and the flange and the shell are sealed and installed on the mass spectrometry vacuum chamber, so that the insulation head, the sliding block, the insulation tube, the fixed sleeve, and the reset spring are all in a vacuum environment.

[0021] The fast avoidance gas chromatography-mass spectrometry transmission line is characterized in that the rear end of the insulation tube is connected to a hollow stud, the rear end of the hollow stud is provided with a plug, the chromatographic column passes through the plug, the hollow stud and the insulation tube in sequence, and a butterfly hand-tightening nut is connected to the rear end of the hollow stud to press the plug against the chromatographic column.

[0022] In the fast avoidance gas chromatography-mass spectrometry transmission line, a nut sleeve is sleeved on the push piece and is fixed with a pin to form the butterfly-shaped hand-tightened nut.

[0023] The fast avoidance gas chromatography-mass spectrometry transmission line is characterized in that a spherical handle is provided on the slide rod of the slide block.

[0024] The beneficial effects of the utility model are as follows:

[0025] 1. The transmission line and ion source can be quickly separated without dismantling the hardware, making the disassembly and assembly of the ion source more convenient.

[0026] 2. The matching insulation head can be replaced according to the type of ion source.

[0027] 3. The transmission line has good thermal insulation effect, adopts hollow design, and the end face is in close contact with the ion source, which can better maintain the temperature, make the temperature around the chromatographic column uniform, and avoid sample condensation.

[0028] 4. The ion vacuum welding process is adopted, which has good sealing and high vacuum degree.

[0029] 5. There are two slides on the slide, which makes the slide more comfortable and free of jams. It has an anti-slip setting, so the slide block will not slip when in the avoidance position.

[0030] 6. No tools are required, and the chromatographic column on the transmission line can be easily installed through the butterfly hand nut. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional schematic diagram of the transmission line of the utility model;

[0032] Figure 2 An exploded diagram of the transmission line of the utility model;

[0033] Figure 3 It is a schematic diagram of the butterfly-shaped hand-tightening nut structure of the transmission line in the utility model;

[0034] Figure 4 It is a schematic diagram of the installation of the transmission line in the utility model.

[0035] Explanation of the reference numerals: 1-chromatographic column; 2-insulation head; 3-sliding block; 4-first handle; 5-sliding cylinder; 6-locking nut; 7-insulation tube; 8-fixed sleeve; 9-flange; 10-hollow stud; 11-nut sleeve; 12-first pin; 13-thrust piece; 14-second pin; 15-plug; 16-insulation pad; 17-housing; 18-insulation fiber blanket; 19-heating block; 20-reset spring; 21-second handle; 22-heating rod; 23-temperature sensor; 24-mass spectrometer vacuum chamber; 25-butterfly hand-tightening nut. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] like Figure 1 and Figure 2 The figure shows the general assembly structure schematic diagram and explosion diagram of the transmission line of one embodiment of the utility model. The utility model provides a fast avoidance gas chromatography-mass spectrometry transmission line, which is composed of an insulation head 2, a sliding block 3, a first handle 4, a slide cylinder 5, a locking nut 6, an insulation tube 7, a fixed sleeve 8, a flange 9, a hollow stud 10, a nut sleeve 11, a first pin 12, a push piece 13, a second pin 14, a plug 15, an insulation pad 16, a shell 17, an insulation fiber blanket 18, a heating block 19, a reset spring 20, a second handle 21, a heating rod 22, and a temperature sensor 23.

[0038] Among them, the rear end of the insulation pipe 7 ( Figure 1 The inner side of the hollow stud 10 is welded into one piece by ion vacuum welding, and the outer side of the hollow stud 10 is welded into one piece by ion vacuum welding with the rear end of the fixed sleeve 8, and a hollow structure is formed between the fixed sleeve 8 and the insulation pipe 7, which can make the insulation more evenly dispersed and prevent temperature concentration; the flange 9 is welded to the shoulder position on one side of the fixed sleeve 8 close to the head end by ion vacuum welding;

[0039] like Figure 1As shown, an insulation head 2 is airtightly and slidably sleeved on the outside of the front end of the insulation pipe 7, and a sliding block 3 is sleeved on the insulation head 2. The insulation head 2 is installed as a whole with the sliding block 3 by means of a flange at the rear end. The sliding block 3 is a ring body, and a sliding rod is radially protruded on each of the opposite sides of the ring body. The ring body of the sliding block 3 is installed in the slide cylinder 5, and the two sliding rods can slide in the slide grooves on both sides of the slide cylinder 5. The slide groove is Z-shaped (with an anti-slip function), and includes an open insertion section, a positioning section arranged along the circumferential direction, and a working stroke section arranged along the axial direction from back to front;

[0040] After the heat preservation head 2 is sleeved with the sliding block 3, the sliding block 3 is inserted from the rear end of the slide cylinder 5 and slides to the front end position of the slide cylinder 5. The return spring 20 is sleeved into the slide cylinder 5. The rear end of the slide cylinder 5 abuts against the limit groove inside the head end of the fixed sleeve 8 and is fixed with the locking nut 6. The rear end of the return spring 20 abuts against the head end of the fixed sleeve 8, and the head end of the return spring 20 abuts against the heat preservation head 2, so that the heat preservation head 2 has a tendency to move forward.

[0041] Afterwards, the first handle 4 and the second handle 21 are respectively tightened (preferably through threads) on the slide bars on both sides of the slide block 3 to facilitate manual pushing operation. The first handle 4 and the second handle 21 are designed to be spherical and not uncomfortable to the hand;

[0042] Such arrangement enables the sliding block 3 to have two positions, the first position is the front-end pressing position, which ensures that the heat preservation head 2 presses the injection port of the ion source, and the heat of the ion source can be transferred to the transmission line, ensuring that the temperature of the position far away from the heating block 19 and close to the ion source can also be kept consistent and play a transition role; the second position is the avoiding position, the sliding block 3 compresses the reset spring 20 and is stuck in the positioning section, so that the heat preservation head 2 avoids the ion source, which is convenient for the disassembly and installation of the ion source;

[0043] like Figure 2 As shown, the heating block 19 is provided with installation positions for the heating rod 22 and the temperature sensor 23. The heating rod 22 and the temperature sensor 23 are installed inside the heating block 19 by screws. The heating block 19 is clamped on the fixed sleeve 8 in the form of a U-mouth and then tightened with screws;

[0044] like Figure 1 As shown, the installation process of the thermal insulation structure of the transmission line is that the heating block 19 is sleeved on the fixed sleeve 8, and the thermal insulation pad 16 formed by glass fiber board is installed on the rear end face of the heating block 19. Two layers of thermal insulation fiber blanket 18 are wrapped around the outer circle, and the shape of the thermal insulation fiber blanket 18 is fixed with aluminum foil or copper foil tape, and then the outer shell 17 is put on, and the rear end of the outer shell 17 is connected to the outer peripheral surface of the hollow stud 10; the thermal insulation structure formed in this way can not only maintain the stability of the internal temperature of the transmission line, but also play a role of thermal insulation to prevent people from being scalded.

[0045] like Figure 3As shown, the push piece 13 is sleeved with the nut sleeve 11, and then pinned with the first pin 12 and the second pin 14 to form a butterfly hand-tightening nut 25, which is connected to the rear end of the hollow stud 10 and is used to press the plug 15 provided at the rear end of the hollow stud 10 onto the chromatographic column 1;

[0046] When in use, the chromatographic column 1 passes through the butterfly hand-tightening nut 25, the plug 15, the hollow stud 10, the fixed sleeve 8, the slide 5 and the insulation head 2 in sequence, and the front end reaches the sampling inlet of the ion source. Then the butterfly hand-tightening nut 25 is manually tightened, and the push piece 13 presses the conical plug 15 with the inclined surface, so that the plug 15 presses the chromatographic column 1, which can simplify the installation of the chromatographic column 1, eliminate tools, and can be operated by hand, which is simple and convenient.

[0047] The flange 9 and the housing 17 of the transmission line are integrally mounted on the mass spectrometer vacuum chamber 24 (eg Figure 4 As shown), a perfluorinated high-temperature resistant sealing ring is used to seal the mass spectrometer vacuum chamber 24 and the flange 9 (not shown), so that the insulation head 2, the sliding block 3, the first handle 4, the slide 5, the locking nut 6, the insulation tube 7, the fixed sleeve 8, the reset spring 20, and the second handle 21 are all in a vacuum environment to ensure that the temperature of the chromatographic column 1 is uniform.

[0048] After the ion source has been used for a period of time, it needs to be cleaned, so it needs to be removed. Before removal, the transmission line needs to be placed in a hidden position before removal.

[0049] In the initial state, the insulation head 2 is pressed tightly in the groove of the injection port of the ion source by the return spring 20. The first handle 4 and the second handle 21 are pushed by hand or tweezers. The first handle 4 and the second handle 21 drive the sliding block 3, and the sliding block 3 drives the insulation head 2 to move backward. When it moves to the avoidance position, the sliding block 3 is rotated, and the sliding block 3 is stuck in the avoidance position and remains motionless. Loosen the butterfly hand nut 25 by hand, and pull the chromatographic column 1 out of the ion source. At this time, the ion source can be removed for cleaning.

[0050] After the ion source is cleaned and installed, the chromatographic column 1 is inserted into the ion source injection port, and the butterfly hand nut 25 is tightened by hand. At this time, the butterfly hand nut 25 presses the plug 15 and fixes the chromatographic column 1 at the same time; the sliding block 3 is rotated, and the sliding block 3 slides over the protruding limit point and returns to the track, and the reset spring 20 automatically pushes the sliding block 3 to the clamping position, so that the insulation head 2 presses the injection port of the ion source.

[0051] It can be seen that the utility model provides a fast avoidance gas chromatography-mass spectrometry transmission line, and the beneficial effects are as follows:

[0052] 1. The transmission line and ion source can be quickly separated without dismantling the hardware, making the disassembly and assembly of the ion source more convenient.

[0053] 2. The matching insulation head can be replaced according to the type of ion source.

[0054] 3. The transmission line has good thermal insulation effect, adopts hollow design, and the end face is in close contact with the ion source, which can better maintain the temperature, make the temperature around the chromatographic column uniform, and avoid sample condensation.

[0055] 4. The ion vacuum welding process is adopted, which has good sealing and high vacuum degree.

[0056] 5. There are two slides on the slide, which makes the slide more comfortable and free of jams. It has an anti-slip setting, so the slide block will not slip when in the avoidance position.

[0057] 6. No tools are required, and the chromatographic column on the transmission line can be easily installed through the butterfly hand nut.

Claims

1. A fast avoidance gas chromatography-mass spectrometry transmission line, characterized in that: It includes a heat preservation head, a sliding block, a sliding cylinder, a fixed sleeve, a return spring and a heat preservation pipe, wherein: The outer side of the insulation tube is sleeved with fixed sleeves at intervals, and the chromatographic column can pass through the insulation tube; The sliding tube is sleeved on the outside of the insulation tube, and its rear end is connected to the front end of the fixed sleeve; The heat preservation head is airtight and slidably sleeved on the front outer side of the heat preservation pipe and is placed in the slide cylinder; One end of the return spring abuts against the heat preservation head, and the other end abuts against the fixed sleeve, so as to push the heat preservation head forward to the compression position under normal conditions; The sliding block is connected to the insulation head and partially extends out of the slide cylinder for operation and drives the insulation head to move backward on the insulation tube to a avoidance position; one of the sliding block and the slide cylinder is provided with a slide groove, and the other is provided with a slide rod that is inserted into the slide groove, and the slide groove includes a working stroke section corresponding to the pressing position and a positioning section corresponding to the avoidance position.

2. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 1, characterized in that: The heat preservation head is installed integrally with the sliding block by means of a flange at the rear end.

3. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 1, characterized in that: A sliding rod is radially protruded from opposite sides of the sliding block, and a sliding groove is radially protruded from opposite sides of the sliding cylinder.

4. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 1, characterized in that: The rear end of the insulation tube is sealed and connected to the head end of a hollow stud, the rear end of the hollow stud can be inserted into the chromatographic column, and the hollow stud is also sleeved with the rear end of the fixed sleeve, a hollow structure is formed between the fixed sleeve and the insulation tube, and a heating block is provided on the outside of the fixed sleeve.

5. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 4, characterized in that: A heating rod and a temperature sensor are installed inside the heating block.

6. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 4, characterized in that: An insulation pad is installed on the rear end face of the heating block, an insulation fiber blanket is wrapped around the outer ring, and the shape of the insulation fiber blanket is fixed with aluminum foil or copper foil tape. The outer side of the insulation fiber blanket is covered with an outer shell, and the rear end of the outer shell is connected to the outer peripheral surface of the hollow stud.

7. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 6, characterized in that: A flange is welded on the fixed sleeve, and the flange and the shell are sealed and installed on the mass spectrometer vacuum cavity, so that the insulation head, the sliding block, the insulation tube, the fixed sleeve and the reset spring are all in a vacuum environment.

8. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 1, characterized in that: The rear end of the insulation tube is connected to a hollow stud, and a plug is provided at the rear end of the hollow stud. The chromatographic column passes through the plug, the hollow stud and the insulation tube in sequence. A butterfly hand-tightening nut is connected to the rear end of the hollow stud to press the plug against the chromatographic column.

9. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 8, characterized in that: The nut sleeve is put on the push piece and is fixed with a pin to form the butterfly-shaped hand-tightening nut.

10. The fast avoidance gas chromatography-mass spectrometry transmission line according to claim 1, characterized in that: A spherical handle is arranged on the slide rod of the slide block.

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