Interface device of gas chromatograph-mass spectrometer

Abstract

The utility model relates to the technical field of a gas chromatograph-mass spectrometer, and discloses a gas chromatograph-mass spectrometer interface device which comprises a gas inlet pipe, a gas pipe connector is arranged at the end part of the gas inlet pipe, a sample input pipe is arranged at the side edge of the gas inlet pipe, and a gas outlet pipe is arranged at the side edge of the gas inlet pipe. A gas flow rate adjusting assembly is arranged between the sample input pipe and the gas inlet pipe, the gas flow rate adjusting assembly is arranged between the gas inlet pipe and the sample input pipe, and a flow rate adjusting ball body is rotationally arranged in a spherical rotating cavity in the gas flow rate adjusting assembly; a middle conveying hole is formed in the middle of the flow rate adjusting ball body, a user can drive the worm through the servo motor, and the angle between the middle conveying hole in the middle of the flow rate adjusting ball body and the conveying channel is deflected and adjusted so as to adjust the corresponding gas flow rate, so that the gas analysis rate can be increased by adjusting the high gas flow rate; the low flow speed can improve the separation degree of the gas, and a user can flexibly adjust and use the device more conveniently.

Description

Technical Field

[0001] This utility model relates to the field of gas chromatography-mass spectrometry (GC-MS) technology, specifically to an interface device for a gas GC-MS. Background Technology

[0002] Gas chromatography-mass spectrometry (GC-MS) is a modern analytical instrument that combines the excellent separation and resolution capabilities of GC with the strong identification and high sensitivity of mass spectrometry, enabling qualitative and quantitative analysis of complex organic compounds. The GC-MS interface is a key component of the instrument, serving as the bridge between the GC module and the mass spectrometry module. Traditional GC-MS instruments typically employ a direct-injection interface structure, where the chromatographic column is inserted from one end and extends from the other, directly entering the ion source of the mass spectrometry module. Both ends of the interface need to be sealed to maintain the high vacuum of the mass spectrometry module. Any leakage will not only result in sample loss but also severely damage the lifespan of critical components such as the filament of the mass spectrometry module.

[0003] A search revealed a Chinese patent publication number, CN 221745957 U, which discloses an interface device for a gas chromatography-mass spectrometry (GC-MS) instrument. The device includes a sleeve, a connecting shaft, a heating tube, and a sealing ring. The sleeve has an internal mounting cavity with openings at both ends. The connecting shaft is installed within the mounting cavity, with both ends extending out of the sleeve. A through hole is formed along the axial direction of the connecting shaft, with one end serving as an inlet and the other as an outlet. The heating tube is sleeved around the connecting shaft within the mounting cavity. The sealing ring is located on the sleeve at the outlet end. This application improves upon the uneven heating of traditional heating rods by using ceramic tube heating and employs an O-ring press-fit method for interface sealing. The device features a simple structure, convenient installation, and no cold spots throughout the process.

[0004] The gas chromatography-mass spectrometry interface in the aforementioned patent still has certain shortcomings. The existing gas chromatography-mass spectrometry interface is difficult to effectively control the inlet gas flow rate. Consequently, when users need to improve gas resolution, a higher flow rate will reduce the resolution analysis, while a lower gas flow rate will prolong the gas analysis time, making it difficult to adapt to users' specific and flexible use. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a gas chromatography-mass spectrometry (GC-MS) interface device, which solves the problem that existing GC-MS interfaces are difficult to effectively control the inlet gas flow rate. Consequently, when users need to improve gas separation, higher flow rates will reduce the separation analysis, while lower gas flow rates will prolong the gas analysis time, making it difficult to adapt to users' specific and flexible needs.

[0006] This utility model provides the following technical solution: a gas chromatography-mass spectrometry interface device, including an inlet pipe, an air pipe connector at the end of the inlet pipe, a sample delivery pipe connected to the air pipe connector, a sample input pipe on the side of the inlet pipe, a gas flow rate regulating component between the sample input pipe and the inlet pipe, and a first connecting flange at the end of both the inlet pipe and the sample input pipe, with a plurality of fastening bolts evenly inserted on the side of the first connecting flange;

[0007] The gas flow rate regulating assembly includes a flow rate regulating seat, a spherical rotating cavity in the center of the flow rate regulating seat, two symmetrical conveying channels on both sides of the spherical rotating cavity, and a second connecting flange at the end of each conveying channel. The second connecting flange is connected to the first connecting flange by fastening bolts. A flow rate regulating sphere is rotatably arranged inside the spherical rotating cavity, and a central conveying hole is opened in the center of the flow rate regulating sphere. Ball limiting seats are arranged around the inner wall of the spherical rotating cavity, and the inner sidewalls of the ball limiting seats are in contact with the outer wall of the flow rate regulating sphere. A top opening is opened at the top of the spherical rotating cavity, and a mounting groove is opened at the top of the top opening. A transmission connecting rod is inserted into the top opening, and the bottom end of the transmission connecting rod is fixedly connected to the top of the flow rate regulating sphere. The transmission connecting rod and the mounting groove are rotatably connected by a connecting bearing. A top mounting chamber is provided at the top of the flow rate regulating seat, a worm gear is provided on the transmission connecting rod, and a worm is rotatably arranged on the side of the top mounting chamber.

[0008] Preferred technical solution 1: The worm and the worm wheel mesh and drive each other, with one end of the worm rotating through the top mounting compartment.

[0009] Preferred technical solution 2: A servo motor is provided on the outside of the top mounting compartment, and the end of the servo motor is fixedly connected to the end of the worm gear.

[0010] Preferred technical solution 3: The conveying channel is connected to the spherical rotating cavity, and the inner diameter of the conveying channel is the same as that of the central conveying hole.

[0011] This design allows the airflow through the central conveying hole to exit the conveying channel more smoothly.

[0012] Preferred technical solution four: The inner wall of the sphere limiting seat is in a curved arc shape that fits against the outer wall of the flow rate regulating sphere.

[0013] This design enables a tighter seal between the flow rate regulating ball and the spherical rotating cavity when the central conveying hole on the flow rate regulating ball rotates to the vertical direction of the conveying channel.

[0014] Preferred technical solution five: A sealing gasket is provided at the junction of the tracheal connector and the end of the air inlet pipe.

[0015] This solution enables a tighter connection between the intake pipe and the air pipe connector.

[0016] Compared with the prior art, the present invention provides an interface device for a gas chromatography-mass spectrometry system, which has the following advantages:

[0017] (1) This utility model provides a gas flow rate regulating component between the gas inlet pipe and the sample input pipe. The gas flow rate regulating component has a flow rate regulating ball rotating inside the spherical rotating cavity. The flow rate regulating ball has a central delivery hole in its middle. When the user needs to adjust the gas flow rate entering the gas chromatograph-mass spectrometer, the user can drive the worm gear through the servo motor, and drive the flow rate regulating ball to rotate through the worm wheel and the transmission connecting rod. This adjusts the angle between the central delivery hole and the delivery channel of the flow rate regulating ball, thereby adjusting the corresponding gas flow rate. A higher gas flow rate can improve the gas analysis rate, while a lower flow rate can improve the gas separation degree, making it more convenient for the user to adjust and use flexibly. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0019] Figure 2 For the present utility model Figure 1 Enlarged view of the structure of the first connecting flange in the middle;

[0020] Figure 3 For the present utility model Figure 1 Internal cross-sectional view of the gas flow rate regulating component;

[0021] Figure 4 For the present utility model Figure 3 Enlarged view of the structure with the mounting groove in the middle.

[0022] In the diagram: 1. Inlet pipe; 2. Gas pipe connector; 3. Sample delivery pipe; 4. Sample input pipe; 5. Gas flow rate regulating component; 6. First connecting flange; 7. Fastening bolts;

[0023] 501. Flow rate regulating seat; 502. Spherical rotating cavity; 503. Conveying channel; 504. Second connecting flange; 505. Flow rate regulating ball; 506. Central conveying hole; 507. Ball limiting seat; 508. Top opening; 509. Mounting groove; 510. Transmission connecting rod; 511. Connecting bearing; 512. Top mounting compartment; 513. Worm gear; 514. Worm; 515. Servo motor. Detailed Implementation

[0024] Please see Figure 1-4 ,

[0025] Example 1: An interface device for a gas chromatography-mass spectrometry instrument includes an inlet pipe 1, a gas pipe connector 2 at the end of the inlet pipe 1, a sample delivery pipe 3 connected to the gas pipe connector 2, a sample input pipe 4 on the side of the inlet pipe 1, a gas flow rate regulating component 5 between the sample input pipe 4 and the inlet pipe 1, a first connecting flange 6 at the end of both the inlet pipe 1 and the sample input pipe 4, and a plurality of fastening bolts 7 evenly inserted on the side of the first connecting flange 6.

[0026] The gas flow rate regulating component 5 includes a flow rate regulating seat 501. A spherical rotating cavity 502 is provided in the middle of the flow rate regulating seat 501. Two conveying channels 503 are symmetrically opened on both sides of the spherical rotating cavity 502. A second connecting flange 504 is provided at the end of each conveying channel 503. The second connecting flange 504 is connected to the first connecting flange 6 by fastening bolts 7. A flow rate regulating ball 505 is rotatably arranged inside the spherical rotating cavity 502. A central conveying hole 506 is opened in the middle of the flow rate regulating ball 505. Ball limiting seats 507 are provided around the inner wall of the spherical rotating cavity 502. The inner sidewall of the ball limiting seat 507 is in contact with the outer wall of the flow rate regulating ball 505. A top opening 508 is opened at the top of the spherical rotating cavity 502. An installation groove 509 is opened at the top of the top opening 508.

[0027] A transmission connecting rod 510 is inserted into the top opening 508. The bottom end of the transmission connecting rod 510 is fixedly connected to the top end of the flow rate regulating ball 505. The transmission connecting rod 510 and the mounting groove 509 are rotatably connected by a connecting bearing 511. A top mounting chamber 512 is provided on the top of the flow rate regulating seat 501. A worm gear 513 is provided on the transmission connecting rod 510. A worm 514 is rotatably provided on the side of the top mounting chamber 512. The worm 514 and the worm gear 513 mesh and drive each other. One end of the worm 514 rotatably passes through the top mounting chamber 512. A servo motor 515 is provided on the outside of the top mounting chamber 512. The end of the servo motor 515 is fixedly connected to the end of the worm 514.

[0028] Example 2: The difference between this example and Example 1 is that the conveying channel 503 is connected to the spherical rotating cavity 502, and the inner diameter of the conveying channel 503 is the same as that of the central conveying hole 506.

[0029] This allows the airflow through the central conveying hole 506 to exit more smoothly from the conveying channel 503.

[0030] Example 3: The difference between this example and Example 1 is that the inner wall of the ball limiting seat 507 is a curved arc shape that fits against the outer wall of the flow rate regulating ball 505.

[0031] When the central conveying hole 506 on the flow rate regulating ball 505 rotates to the vertical direction of the conveying channel 503, the seal between the flow rate regulating ball 505 and the spherical rotating cavity 502 becomes tighter.

[0032] Example 4: The difference between this example and Example 1 is that a sealing gasket is provided at the junction of the air pipe connector 2 and the end of the air inlet pipe 1.

[0033] This makes the connection between the air intake pipe 1 and the air pipe connector 2 tighter.

[0034] In this embodiment, since the existing gas chromatography-mass spectrometry interface is difficult to effectively control the inlet gas flow rate, when the user needs to improve the gas resolution, a higher flow rate will reduce the resolution analysis, while a lower gas flow rate will prolong the gas analysis time, making it difficult to adapt to the user's specific and flexible use.

[0035] In summary, in practical implementation, when the user connects an external gas source through the sample delivery pipe 3 and then delivers the gas to the gas chromatograph-mass spectrometer for detection through the inlet pipe 1 and the sample input pipe 4, a gas flow rate regulating component 5 is provided between the inlet pipe 1 and the sample input pipe 4. The flow rate regulating ball 505 in the gas flow rate regulating component 5 has a central delivery hole 506 in the middle, and the central delivery hole 506 has the same inner diameter as the delivery channel 503. The top of the flow rate regulating ball 505 is connected to a transmission connecting rod 510. The transmission connecting rod 510 and the flow rate regulating seat 501 are rotatably connected through a connecting bearing 511, which makes the worm gear 513 on the transmission connecting rod 510 rotate more stably. The side of the worm gear 513 meshes with the worm 514.

[0036] Then, under the drive of the servo motor 515 to the worm 514, the worm 514 drives the worm wheel 513 to rotate. The worm wheel 513 drives the transmission connecting rod 510 to rotate, which in turn drives the flow rate regulating ball 505 set in the spherical rotating cavity 502 to rotate. This causes the central conveying hole 506 opened in the middle of the flow rate regulating ball 505 to gradually shift away from the conveying channel 503, thereby effectively regulating the airflow velocity through the gas flow rate regulating component 5. Furthermore, since the worm wheel 513 and the worm 514 have a certain self-locking property, the flow rate regulating ball 505 will not deflect again due to the impact of the airflow after deflection.

[0037] When users need to improve gas separation, they can rotate the flow rate regulating ball 505 to adjust the angle between the central delivery hole 506 and the delivery channel 503, thereby reducing the gas flow rate through the spherical rotating cavity 502 and improving gas separation. When users need to speed up gas analysis, they can rotate the flow rate regulating ball 505 again to keep the central delivery hole 506 and the delivery channel 503 in a straight line, thereby increasing the rate at which gas passes through the spherical rotating cavity 502 and thus speeding up the gas analysis of the gas chromatograph-mass spectrometer, making it more convenient and flexible for users.

Claims

1. An interface device for a gas chromatograph mass spectrometer, comprising an inlet tube (1), characterised in that: The end of the air inlet pipe (1) is provided with an air pipe connector (2), a sample delivery pipe (3) is communicated on the air pipe connector (2), the side of the air inlet pipe (1) is provided with a sample input pipe (4), a gas flow rate adjusting assembly (5) is arranged between the sample input pipe (4) and the air inlet pipe (1), the ends of the air inlet pipe (1) and the sample input pipe (4) are provided with first connecting flanges (6), and a plurality of fastening bolts (7) are uniformly inserted into the side of the first connecting flange (6). The gas flow rate adjusting assembly (5) comprises a flow rate adjusting seat (501), a spherical rotating cavity (502) is arranged in the middle of the flow rate adjusting seat (501), two delivery channels (503) are symmetrically arranged on the two sides of the spherical rotating cavity (502), a second connecting flange (504) is arranged at the end of the delivery channel (503), the second connecting flange (504) is connected with the first connecting flange (6) through the fastening bolt (7), a flow rate adjusting ball (505) is rotatably arranged in the spherical rotating cavity (502), a middle delivery hole (506) is arranged in the middle of the flow rate adjusting ball (505), a ball limiting seat (507) is arranged around the inner wall of the spherical rotating cavity (502), the inner side wall of the ball limiting seat (507) is in close contact with the outer wall of the flow rate adjusting ball (505), a top opening (508) is arranged at the top of the spherical rotating cavity (502), an installation groove (509) is arranged at the top of the top opening (508), a transmission connecting rod (510) is inserted into the top opening (508), the bottom end of the transmission connecting rod (510) is fixedly connected with the top end of the flow rate adjusting ball (505), the transmission connecting rod (510) is rotatably connected with the installation groove (509) through a connecting bearing (511), a top installation bin (512) is arranged at the top of the flow rate adjusting seat (501), a worm wheel (513) is arranged on the transmission connecting rod (510), and a worm (514) is rotatably arranged on the side of the top installation bin (512).

2. A GC-MS interface according to claim 1, characterized in that: The worm (514) is in meshing transmission with the worm wheel (513), and one end of the worm (514) rotatably penetrates the top installation bin (512).

3. A GC-MS interface according to claim 2, characterised in that: A servo motor (515) is arranged outside the top installation bin (512), and the end of the servo motor (515) is fixedly connected with the end of the worm (514).

4. A GC-MS interface according to claim 3, characterised in that: The delivery channel (503) is communicated with the spherical rotating cavity (502), and the inner diameter of the delivery channel (503) is the same as that of the middle delivery hole (506).

5. A gas chromatograph-mass spectrometer interface as defined in claim 4, characterized by: The inner side wall of the ball limiting seat (507) is in the shape of a curved arc which is in close contact with the outer wall of the flow rate adjusting ball (505).

6. A gas chromatograph-mass spectrometer interface as defined in claim 5, characterized by: A sealing gasket is arranged at the joint between the air pipe connector (2) and the end of the air inlet pipe (1).

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