A new type of multi-channel liquid chromatography flow splitting device

Abstract

The present invention proposes a novel multi-channel liquid chromatography splitting device, including a center plate, a two-way joint and a connecting pipeline. The center plate is provided with a center hole along the central axis, a constant volume pin is installed in the center hole, the center hole is divided into a primary step hole, a secondary step hole and a tertiary step hole with successively decreasing diameters, the constant volume pin includes an end cap, an intermediate section and a pin matched with the center hole, a locking nut is connected to the end of the pin, and the diameter of the pin is smaller than the inner diameter of the secondary step hole; a plurality of splitting grooves are radially arranged on the side of the center plate, a liquid separation hole connected to the secondary step hole is arranged on the bottom surface of the splitting groove, a two-way joint is installed in the splitting groove, a connecting pipeline passes through the two-way joint and is inserted into the liquid separation hole, and a conical pressure ring and a joint nut are installed at the other end of the two-way joint. The multi-channel liquid chromatography splitting device described in the present invention effectively reduces the dead volume outside the column, and can withstand high pressure and reduce the extra-column effect.

Description

Technical Field

[0001] The invention belongs to the field of liquid chromatography instruments, and in particular relates to a novel multi-channel liquid chromatography flow splitting device. Background Art

[0002] The extra-column effect refers to the cause of chromatographic peak broadening outside the chromatographic column, which is mainly caused by the injection device, the detection cell, and the connecting pipes between them and the chromatographic column, and the connectors used between the pipes. Minimizing the extra-column effect as much as possible is also the constant pursuit of the technological innovation of liquid chromatography-related instrument manufacturing. Therefore, the size of the injection device, the detection cell and the connecting pipe becomes particularly important. However, the size of the injection device, the detection cell and other components is constant for a given chromatographic instrument, and what can be changed is the connecting pipe and the connectors used between the pipes. In order to improve the column efficiency, the volume of the connecting pipe and the connector must be reduced. However, when the flow rate remains unchanged, the pressure on the connecting pipe and its pipe connectors increases accordingly after the volume is reduced. With the increasing maturity of packing technology, the particle size of the packing is getting smaller and smaller. How to reduce the dead volume outside the column of the connector while making it withstand higher pressure has become one of the key factors affecting the development of chromatographic technology. Summary of the invention

[0003] In view of the technical problems that the pipeline connectors of existing liquid chromatography instruments have a relatively large overall volume and a large internal dead volume, the present invention proposes a novel eight-channel liquid chromatography splitter device which adopts a circumferential array connector arrangement to effectively reduce the dead volume of the inner cavity.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A novel multi-channel liquid chromatography shunt device comprises a center plate, a two-way joint and connecting pipelines, wherein the center plate is provided with a center hole along the central axis, a constant volume pin is installed in the center hole, the center hole is divided into a primary step hole, a secondary step hole and a tertiary step hole with successively decreasing diameters, the constant volume pin comprises an end cap, an intermediate section and a pin column matched with the center hole, a locking nut is connected to the end of the pin column, and the diameter of the pin column is smaller than the inner diameter of the secondary step hole; a plurality of shunt grooves are radially arranged on the side surface of the center plate, a liquid separation hole connected to the secondary step hole is arranged on the bottom surface of the shunt groove, a two-way joint is installed in the shunt groove, the connecting pipeline passes through the two-way joint and is inserted into the liquid separation hole, and a conical pressure ring and a joint nut are installed at the other end of the two-way joint.

[0006] Preferably, the number of the diversion channels is 3-10.

[0007] Preferably, the number of the diversion channels is 6-8.

[0008] Preferably, the diverter grooves are evenly distributed on the sides of the center plate.

[0009] Preferably, the two-way connector is connected to the diversion trough via threads.

[0010] Preferably, a first sealing groove is provided on the bottom surface of the first-stage step hole, and a first sealing ring is installed in the first sealing groove.

[0011] Preferably, a second sealing groove and a pressure ring groove are provided at the end of the three-step step hole, a second sealing ring is installed in the second sealing groove, and a pressure ring is installed in the pressure ring groove.

[0012] Preferably, a reamer hole is provided at the other end of the two-way joint, and a conical pressure ring is installed in the reamer hole.

[0013] Preferably, the expansion angle is 35-50°.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are:

[0015] 1. The present invention adopts a circular array joint arrangement method, which effectively reduces the dead volume of the module cavity and reduces the extra-column effect.

[0016] 2. The connecting pipe of the diversion channel and the center plate adopt interference fit to avoid sample overflow.

[0017] 3. The two-way joint is fixedly connected to the center plate by threads, conical pressure rings and joint nuts, achieving a good sealing effect and being able to withstand high pressure.

[0018] 4. Multi-step holes and sealing rings are used between the center plate and the constant volume pin to achieve a firm seal to prevent sample leakage under high pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A three-dimensional diagram of a center plate of a liquid chromatography splitting device of the present invention;

[0020] Figure 2 It is a schematic structural diagram of a cross-sectional view of a center plate of a liquid chromatography flow splitting device of the present invention;

[0021] Figure 3 for Figure 2 Cross-sectional view in the middle BB direction;

[0022] Figure 4 It is a cross-sectional view of a two-way joint of a liquid chromatography splitting device of the present invention;

[0023] Figure 5 It is a schematic diagram of the overall structure of the liquid chromatography splitting device of the present invention;

[0024] Figure 6 is an internal cross-sectional view of the liquid chromatography splitting device of the present invention;

[0025] Figure 7It is a partial cross-sectional view of the liquid chromatography splitting device of the present invention;

[0026] In the above figures: 1. center plate; 11. center hole; 111. first step hole; 112. second step hole; 113. third step hole; 114. first sealing groove; 115. first sealing ring; 116. second sealing groove; 117. second sealing ring; 118. pressure ring groove; 119. pressure ring; 12. diverter groove; 13. liquid separation hole; 14. fixing hole; 2. constant volume pin; 21. end cap; 22. middle section; 23. pin column; 24. locking nut; 3. two-way joint; 31. expansion hole; 32. conical pressure ring; 33. joint nut; 4. connecting pipeline. DETAILED DESCRIPTION

[0027] In order to better understand the present invention, a detailed description is given below in conjunction with the accompanying drawings and embodiments.

[0028] Example: Figure 1-Figure 3 As shown, a novel multi-channel liquid chromatography flow splitting device includes a flat center plate 1, preferably the center plate 1 is selected to be a regular polygon or a circle, and the circle is selected in this embodiment. A stepped center hole 11 is provided at the center axis of the center plate 1, and the center hole 11 is divided into a first-level step hole 111, a second-level step hole 112 and a third-level step hole 113 with successively decreasing diameters, and a constant volume pin 2 is installed in the center hole 11.

[0029] The constant volume pin 2 includes an end cap 21, an intermediate section 22 and a pin 23 that match the center hole 11, and the end of the pin 23 is connected to a locking nut 24. When the constant volume pin 2 is installed in the center hole 11, the end cap is located in the primary step hole 111, and the two are tightly matched; the intermediate section 22 is located in the secondary step hole 112, and the diameter of the intermediate section 22 is smaller than the inner diameter of the secondary step hole 112, thereby forming a liquid flow gap. The pin 23 is located in the third step hole 113, and is tightly matched. The locking nut 24 further fixes the constant volume pin 2 in the center hole 11.

[0030] like Figure 4-7As shown, more than three diverter grooves 12 are radially arranged on the side of the center plate 1, and a liquid separation hole 13 connected to the secondary step hole 112 is arranged on the bottom surface of the diverter groove 12. A two-way joint 3 is screwed in the diverter groove 12 by a thread, and a connecting pipe 4 passes through the two-way joint 3 and is inserted into the liquid separation hole 13 to form a diverter channel. The number of diverter grooves 12 can be selected as needed, especially 6-8, and the present embodiment is set to 8, which are evenly distributed on the circumference of the center plate 1. The outer diameter of the connecting pipe 4 is slightly larger than the inner diameter of the liquid separation hole 13. When installing, the connecting pipe 4 passes through the two-way joint 3 and is pressed into the liquid separation hole 13 to ensure that the sample solution does not flow back into the liquid separation hole 13. In order to further fix the connecting pipe 4, the other end of the two-way joint 3 is provided with an expansion hole 31, and a conical pressure ring 32 is placed in the expansion hole 31. A joint nut 33 is screwed on the two-way joint 3, and the conical pressure ring 32 is pressed tightly, and the further connecting pipe 4 is locked in the two-way joint 3. The expansion angle α of the expansion hole 31 is 35-50°, and is preferably 40° in this embodiment.

[0031] In order to prevent the sample from leaking under high pressure, a first sealing groove 114 is provided at the bottom of the first-level step hole 111, and a first sealing ring 115 is installed in the first sealing groove. A second sealing groove 116 and a pressure ring groove 118 are provided at the end of the third-level step hole 113, a second sealing ring 117 is installed in the second sealing groove 116, and a pressure ring 119 is installed in the pressure ring groove 118. After the locking nut 24 is screwed on the constant volume pin 2, the constant volume pin 2 and the center plate 1 form a firm sealing structure that can withstand a large pressure.

[0032] A fixing hole 14 is also provided in the axial direction of the center plate 1. The fixing hole 14 should be arranged along the circumference away from the position of the diversion hole, so as to fix the entire diversion device inside the equipment.

[0033] The liquid chromatography splitter device of the present invention adopts a circumferential array joint arrangement mode, which effectively reduces the dead volume of the module cavity. The connecting pipeline 4 of the splitter channel adopts an interference fit with the center plate 1 to prevent sample overflow. The two-way joint 3 is fixedly connected to the center plate 1 by threads and a conical pressure ring 32 and a joint nut to achieve a good sealing effect. Multi-step stepped holes and sealing rings are used between the center plate 1 and the constant volume pin 2 to achieve a firm seal to prevent sample leakage under high pressure. The multi-channel liquid chromatography splitter device described in the present invention effectively reduces the dead volume outside the column, and the ingenious connection structure and stepped sealing structure are used between the components, which can withstand high pressure and reduce the extra-column effect.

[0034] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A novel multi-channel liquid chromatography flow splitting device, characterized in that: It includes a center plate, a two-way joint and a connecting pipeline. The center plate is provided with a center hole along the central axis, a constant volume pin is installed in the center hole, the center hole is divided into a first-level step hole, a second-level step hole and a third-level step hole with successively decreasing diameters, the constant volume pin includes an end cap, an intermediate section and a pin column matched with the center hole, a locking nut is connected to the end of the pin column, and the diameter of the pin column is smaller than the inner diameter of the second-level step hole; a plurality of diversion grooves are radially arranged on the side of the center plate, a liquid separation hole connected to the second-level step hole is arranged on the bottom surface of the diversion groove, a two-way joint is installed in the diversion groove, the connecting pipeline passes through the two-way joint and is inserted into the liquid separation hole, an expansion hole is arranged at the other end of the two-way joint and a joint nut is screwed on, a conical pressure ring is installed in the expansion hole, and the expansion angle of the expansion hole is 35-50°; A first sealing groove is arranged on the bottom surface of the first-level step hole, and a first sealing ring is installed in the first sealing groove; a second sealing groove and a pressure ring groove are arranged at the end of the third-level step hole, a second sealing ring is installed in the second sealing groove, and a pressure ring is installed in the pressure ring groove.

2. The novel multi-channel liquid chromatography flow splitting device according to claim 1, characterized in that: The number of the diversion channels is 3-10.

3. The novel multi-channel liquid chromatography flow splitting device according to claim 2 is characterized in that: The number of the diversion channels is 6-8.

4. The novel multi-channel liquid chromatography flow splitting device according to claim 3 is characterized in that: The diverter slots are evenly distributed on the side of the center plate.

5. The novel multi-channel liquid chromatography flow splitting device according to claim 4, characterized in that: The two-way connector is connected to the diversion trough through threads.

6. The novel multi-channel liquid chromatography flow splitting device according to claim 1, characterized in that: The center plate is provided with a fixing hole along the axial direction.

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