A one-control multi-flow EPC module for gas chromatograph

Abstract

The present invention discloses a one-control multi-flow path EPC module for a gas chromatograph, comprising a proportional regulating valve, an air pressure sensor, a fixed base, an upper pressing block and an airflow regulating mechanism, wherein the side wall of the fixed base is fixedly connected with the proportional regulating valve, an air inlet pipe is arranged at the edge of the fixed base, an air pressure sensor is fixedly connected to the lower surface of the fixed base, an upper pressing block is fixedly connected to the upper surface of the fixed base, a plurality of annularly distributed exhaust ports are arranged on the surface of the upper pressing block, and the diameters of the exhaust ports are different, and an movably connected airflow regulating mechanism is arranged at the center of the upper pressing block, and the airflow regulating mechanism comprises a rotating rod, a baffle, a sealing gasket and a conical spring. The present invention is convenient for adjusting the gas flow of the exhaust port according to needs by arranging a plurality of annularly distributed exhaust ports on the surface of the upper pressing block, and cooperating with a rotatable airflow regulating mechanism, and multiple airflows are output simultaneously, so as to meet the use requirements of different airflows during use, thereby greatly reducing the use cost of the EPC module.

Description

Technical Field

[0001] The invention relates to the technical field of gas chromatographs, in particular to a one-control multi-flow path EPC module for gas chromatographs. Background Art

[0002] Gas chromatograph refers to a chromatographic analysis instrument that uses gas as the mobile phase. Its principle is mainly to use the differences in the boiling point, polarity and adsorption properties of substances to achieve the separation of mixtures. After the sample to be analyzed is vaporized in the vaporization chamber, it is carried into the chromatographic column by the inert gas (i.e., carrier gas, also known as mobile phase). The column contains a liquid or solid stationary phase, and each component in the sample tends to form a distribution or adsorption equilibrium between the mobile phase and the stationary phase. As the carrier gas flows, the sample components are repeatedly distributed or adsorbed / desorbed during movement. The components with high distribution concentrations in the carrier gas flow out of the chromatographic column first, and the components with high distribution concentrations in the stationary phase flow out later. After the components flow out of the chromatographic column, they enter the detector for measurement. Commonly used detectors include electron capture detectors (ECD), hydrogen flame detectors (FID), flame photometric detectors (FPD) and thermal conductivity detectors (TCD). Gas chromatographs are usually used to analyze organic matter in soil that is thermally stable and has a boiling point not exceeding 500°C, such as volatile organic compounds, organochlorine, organophosphorus, polycyclic aromatic hydrocarbons, phthalates, etc. It has the advantages of being fast, effective, and highly sensitive, and plays an important role in soil organic matter research. Samples that can be directly used for gas chromatography analysis must be gas or liquid, so soil samples need to be extracted into a certain solvent through a certain pretreatment method before analysis. Commonly used pretreatment methods include Soxhlet extraction, ultrasonic extraction, oscillation extraction, microwave extraction, etc. In addition, some emerging pretreatment methods such as solid phase extraction, solid phase microextraction, accelerated solvent extraction, and supercritical extraction are also being widely used.

[0003] Gas chromatograph technology is developing rapidly, and electronic pressure / flow control (EPC) technology has been applied to the flow control of the instrument. Its control is flexible and stable, and is very popular among users. However, the key components used for control, such as proportional valves and sensors, are relatively expensive, and the EPC module on the market is only one control module corresponding to one gas output. In actual use, gas flow supply with different flow rates is often required, resulting in the need to use multiple EPC modules, which increases the cost of use and reduces the popularity and promotion of EPC modules. Therefore, a new technical solution needs to be designed to solve this problem. Summary of the invention

[0004] The object of the present invention is to provide a one-control multi-flow path EPC module for a gas chromatograph, which solves the problem that the EPC module in the prior art is relatively high in cost and difficult to popularize and promote.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a one-control multi-flow path EPC module for a gas chromatograph, comprising a proportional control valve, an air pressure sensor, a fixed base, an upper pressure block and an airflow adjustment mechanism, wherein the side wall of the fixed base is fixedly connected with the proportional control valve, an air inlet pipe is provided at the edge of the fixed base, the lower surface of the fixed base is fixedly connected with the air pressure sensor, the upper surface of the fixed base is fixedly connected with the upper pressure block, the surface of the upper pressure block is provided with a plurality of annularly distributed exhaust ports, the diameters of the exhaust ports are different, and an movably connected airflow adjustment mechanism is provided at the center of the upper pressure block, the airflow adjustment mechanism comprises a rotating rod, a baffle, a sealing gasket and a conical spring, the rotating rod passes through the upper pressure block and is movably connected to the upper pressure block, the bottom of the rotating rod is fixedly connected with a baffle, the upper surface of the baffle is fixedly connected with a sealing gasket, and a conical spring is provided between the lower surface of the baffle and the fixed base.

[0006] As an improvement of the above technical solution, an air collecting groove is provided at the center of the upper surface of the fixed base, an annular groove is provided at the edge of the air collecting groove, and a sealing ring is provided inside the annular groove.

[0007] As an improvement of the above technical solution, the side wall of the fixed base is provided with an air outlet and an air inlet, the air inlet is connected to the air inlet pipe, the air outlet is connected to the air collecting groove, and the air pressure sensor is fixed in the flow channel between the air outlet and the air collecting groove.

[0008] As an improvement of the above technical solution, the baffle is fan-shaped and has an arc-shaped edge, and a positioning groove is provided at the edge of the baffle.

[0009] As an improvement of the above technical solution, positioning blocks are fixedly connected to the edges of the exhaust ports, and the positioning blocks are distributed in a one-to-one correspondence with the exhaust ports.

[0010] As an improvement of the above technical solution, a center hole is opened in the center of the upper pressing block, and the rotating rod passes through the center hole and is rotatably connected to the center hole.

[0011] As an improvement of the above technical solution, an edge of the central hole is provided with an annularly distributed airflow output mark, and the airflow output mark corresponds to the exhaust port one by one.

[0012] As an improvement of the above technical solution, a rotating cap is fixedly connected to the top of the rotating rod, and an arc-shaped edge is provided at the edge of the rotating cap, and the position of the arc-shaped edge is the same as that of the baffle.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. The present invention provides a plurality of annularly distributed exhaust ports on the surface of the upper pressing block, and cooperates with a rotatable airflow adjustment mechanism to facilitate the adjustment of the gas flow of the exhaust port according to needs, and multiple airflows are output simultaneously to meet the use requirements of different airflows during use, thereby greatly reducing the use cost of the EPC module.

[0015] 2. The present invention provides exhaust ports of different diameters on the surface of the upper pressure block to facilitate the discharge of gas with different flow rates and improve ease of use. Positioning grooves are provided at the edge of the baffle plate to cooperate with positioning blocks at the edge of the exhaust port to improve the stability of the baffle plate in blocking the exhaust port and avoid gas leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the overall structure of the one-control multi-flow path EPC module for gas chromatograph according to the present invention;

[0017] Figure 2 This is a schematic cross-sectional structure diagram of a one-control multi-flow path EPC module for a gas chromatograph according to the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of the fixed base according to the present invention;

[0019] Figure 4 It is a schematic diagram of the structure of the upper pressing block and the airflow regulating mechanism of the present invention.

[0020] In the figure: proportional control valve-1, air pressure sensor-2, fixed base-3, upper pressure block-4, air flow adjustment mechanism-5, air inlet pipe-6, air outlet-7, rotating rod-8, baffle-9, sealing gasket-10, conical spring-11, air collecting groove-12, annular groove-13, sealing ring-14, air outlet-15, air inlet-16, positioning groove-17, positioning block-18, center hole-19, air flow output mark-20, rotating cap-21, arc rim-22. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0022] See also Figure 1-4The present invention provides a technical solution: a one-control multi-flow path EPC module for a gas chromatograph, comprising a proportional control valve 1, an air pressure sensor 2, a fixed base 3, an upper pressing block 4 and an airflow adjustment mechanism 5, wherein the side wall of the fixed base 3 is fixedly connected with the proportional control valve 1, an air inlet pipe 6 is arranged at the edge of the fixed base 3, the lower surface of the fixed base 3 is fixedly connected with the air pressure sensor 2, the upper surface of the fixed base 3 is fixedly connected with the upper pressing block 4, a plurality of annularly distributed exhaust ports 7 are arranged on the surface of the upper pressing block 4, and the diameters of the exhaust ports 7 are different, and an movably connected airflow adjustment mechanism 5 is arranged at the center of the upper pressing block 4, and the airflow adjustment mechanism 5 comprises a rotating rod 8, a baffle 9, a sealing gasket 10 and a conical spring 11, the rotating rod 8 passes through the upper pressing block 4 and is movably connected with the upper pressing block 4, the bottom of the rotating rod 8 is fixedly connected with the baffle 9, the upper surface of the baffle 9 is fixedly connected with the sealing gasket 10, and a conical spring 11 is arranged between the lower surface of the baffle 9 and the fixed base 3.

[0023] As a further improvement, an air collecting groove 12 is opened in the center of the upper surface of the fixed base 3, an annular groove 13 is opened at the edge of the air collecting groove 12, and a sealing ring 14 is provided inside the annular groove 13. By opening the air collecting groove 12 in the center of the upper surface of the fixed base 3, air can be supplied to the exhaust port 7 on the surface of the upward pressing block 4 conveniently.

[0024] As a further improvement, the side wall of the fixed base 3 is provided with an air outlet 15 and an air inlet 16, the air inlet 16 is connected to the air inlet pipe 6, the air outlet 15 is connected to the air collecting groove 12, and the air pressure sensor 2 is fixed in the flow channel between the air outlet 15 and the air collecting groove 12. By opening the air outlet 15 and the air inlet 16 on the side wall of the fixed base 3, it is convenient to connect with the proportional control valve 1, thereby facilitating the adjustment of the inflowing air pressure.

[0025] As a further improvement, the baffle 9 is fan-shaped and has an arc-shaped edge. A positioning groove 17 is provided at the edge of the baffle 9. By adopting the fan-shaped baffle 9, it is convenient to block multiple exhaust ports 7 as needed, thereby facilitating the adjustment of the air flow of the exhaust ports 7.

[0026] As a further improvement, positioning blocks 18 are fixedly connected to the edges of the exhaust ports 7, and the positioning blocks 18 are distributed in a one-to-one correspondence with the exhaust ports 7. By providing one-to-one corresponding positioning blocks 18 at the edges of the exhaust ports 7, it is convenient to match the positioning grooves 17 at the edges of the baffle 9, thereby improving the stability of the baffle 9.

[0027] As a further improvement, a center hole 19 is opened in the center of the upper pressure block 4, and the rotating rod 8 passes through the center hole 19 and is rotatably connected to the center hole 19. By opening the center hole 19 in the center of the upper pressure block 4, the rotating rod 8 can be easily rotated and adjusted, thereby improving the convenience of the adjustment operation.

[0028] As a further improvement, an annularly distributed airflow output mark 20 is engraved on the edge of the center hole 19, and the airflow output mark 20 corresponds one-to-one with the exhaust port 7. By providing an airflow output mark 20 corresponding one-to-one with the exhaust port 7 on the edge of the center hole 19, it is convenient to check during adjustment, thereby improving the convenience of operation.

[0029] Specifically, a rotating cap 21 is fixedly connected to the top of the rotating rod 8, and an arc-shaped edge 22 is provided at the edge of the rotating cap 21. The arc-shaped edge 22 is in the same position as the baffle 9. By providing an arc-shaped edge 22 at the edge of the rotating cap 21, the position of the baffle 9 can be more intuitively reflected, which facilitates adjustment and operation.

[0030] The present invention provides a plurality of annularly distributed exhaust ports 7 on the surface of the upper pressing block 4, and cooperates with a rotatable airflow regulating mechanism 5 to facilitate the adjustment of the gas flow of the exhaust ports 7 as needed, and multiple airflows are output simultaneously to meet the use requirements of different airflows during use, thereby greatly reducing the use cost of the EPC module.

[0031] Embodiment 1

[0032] When the present invention is in use, the proportional regulating valve 1 and the air pressure sensor 2 are respectively connected to a computer or a controller, and the air source is connected to the air inlet pipe 6 at the edge of the fixed base 3 through a pipeline. After the gas enters the proportional regulating valve 1, the air pressure of the gas is adjusted, and is monitored and corrected in real time through the air pressure sensor 2. After the airflow enters the air collecting tank 12, it is discharged through the exhaust ports 7 of different diameters, thereby realizing the control and use of different airflows.

[0033] Example 2

[0034] When adjusting the flow rate of the airflow, press the rotating rod 8 downward and rotate the rotating rod 8 to adjust the position of the baffle 9. The position of the baffle 9 is determined by the arc edge 22 at the edge of the rotating cap 21. Release the rotating rod 8. Under the action of the conical spring 11, the baffle 9 moves upward, so that the positioning groove 17 at the edge of the baffle 9 is engaged with the positioning block 18. The airflow passes through the exhaust ports 7 of different diameters to discharge gases of different flow rates to meet the needs of use.

[0035] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0036] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A one-control multi-flow EPC module for a gas chromatograph, comprising a proportional control valve (1), a pressure sensor (2), a fixed base (3), an upper pressure block (4) and an airflow adjustment mechanism (5), characterized in that: A proportional regulating valve (1) is fixedly connected to the side wall of the fixed base (3); an air inlet pipe (6) is provided at the edge of the fixed base (3); an air pressure sensor (2) is fixedly connected to the lower surface of the fixed base (3); an upper pressing block (4) is fixedly connected to the upper surface of the fixed base (3); a plurality of annularly distributed exhaust ports (7) are provided on the surface of the upper pressing block (4); the diameters of the exhaust ports (7) are different; an movably connected airflow regulating mechanism (5) is provided at the center of the upper pressing block (4); the airflow regulating mechanism (5) comprises a rotating rod (8), a baffle (9), a sealing gasket (10) and a conical spring (11); the rotating rod (8) passes through the upper pressing block (4) and is movably connected to the upper pressing block (4); a baffle (9) is fixedly connected to the bottom of the rotating rod (8); a sealing gasket (10) is fixedly connected to the upper surface of the baffle (9); and a conical spring (11) is provided between the lower surface of the baffle (9) and the fixed base (3).

2. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 1, characterized in that: An air collecting groove (12) is provided at the center of the upper surface of the fixed base (3), an annular groove (13) is provided at the edge of the air collecting groove (12), and a sealing ring (14) is provided inside the annular groove (13).

3. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 2, characterized in that: The side wall of the fixed base (3) is provided with an air outlet (15) and an air inlet (16); the air inlet (16) is connected to the air inlet pipe (6); the air outlet (15) is connected to the air collecting groove (12); and the air pressure sensor (2) is fixed in the flow channel between the air outlet (15) and the air collecting groove (12).

4. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 1, characterized in that: The baffle plate (9) is fan-shaped and has an arc-shaped edge. A positioning groove (17) is provided at the edge of the baffle plate (9).

5. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 1, characterized in that: Positioning blocks (18) are fixedly connected to the edges of the exhaust ports (7), and the positioning blocks (18) are distributed in a one-to-one correspondence with the exhaust ports (7).

6. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 1, characterized in that: A center hole (19) is opened at the center of the upper pressing block (4), and the rotating rod (8) passes through the center hole (19) and is rotatably connected to the center hole (19).

7. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 6, characterized in that: The edge of the central hole (19) is provided with an annularly distributed airflow output mark (20) engraved thereon, and the airflow output mark (20) corresponds one to one with the exhaust port (7).

8. The one-control-multiple-flow-path EPC module for a gas chromatograph according to claim 1, characterized in that: A rotating cap (21) is fixedly connected to the top of the rotating rod (8), and an arc-shaped edge (22) is provided at the edge of the rotating cap (21), and the position of the arc-shaped edge (22) is the same as that of the baffle (9).

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