Needle sealing assembly
By designing a needle seal assembly including mounting housing, casing, steel pipe and gasket, and using hand screws to achieve rapid replacement of seal integration, the problem of difficulty in replacing needle seals in the prior art is solved, and replacement efficiency and convenience are improved.
Patent Information
- Application Number
- CN202421252960.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-03
- Publication Date
- 2025-04-18
- Estimated Expiration
- 2034-06-03
AI Technical Summary
In the prior art, needle seal replacement is difficult, and it is necessary to disassemble the parts of the entire sample injection device, which is time-consuming and labor-intensive, affecting the work efficiency of after-sales staff.
A needle seal assembly is designed, including mounting housing, casing, steel pipe and gaskets, which integrates the seal into a single unit by hand screws, and can quickly replace the seal integration with just rotating the hand screws.
It greatly reduces the difficulty of replacing the gasket, can be quickly replaced without any auxiliary tools, save time and effort, and reduces the workload of after-sales staff.
Smart Images
Figure CN222774540U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of chromatograph sealing devices, in particular to a needle sealing component. Background Art
[0002] In order to ensure the sealing of the connection between the injection needle and the chromatograph system, a sealing device, i.e., a needle seal, is generally provided at the injection port of the chromatograph. It is usually an annular elastic gasket, which can prevent sample leakage or contamination inside the injection needle. During use, the elastic gasket is very easy to deform, resulting in sealing failure, and the wear amount is extremely large, so it needs to be replaced regularly. The sealing gaskets in the prior art are all separate components, and in order to ensure their stable sealing, the gasket needs to be firmly fixed at the injection port. Therefore, to replace the gasket, all the components of the entire injection device need to be disassembled before the gasket can be taken out with auxiliary tools. It is very difficult and cumbersome to disassemble the gasket when replacing it, which brings great trouble to the work of after-sales staff. Utility Model Content
[0003] In view of the above-mentioned deficiencies in the prior art, the utility model provides a needle seal assembly, which solves the problem of difficulty in replacing the needle seal in the prior art.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:
[0005] A needle sealing assembly is provided, which comprises an installation shell with an installation cavity provided inside, and a sealing assembly is arranged in the installation cavity; the sealing assembly comprises a sleeve, a steel pipe and a gasket fixed to the upper plane of the steel pipe, the sleeve is sleeved on the outside of the gasket and the steel pipe, the gasket is completely located inside the sleeve, and the strength of the sleeve is greater than the strength of the gasket; the lower end of the sleeve is connected to a hand screw that can drive the sleeve to move, and the threaded portion of the hand screw is threadedly connected to the cavity wall of the installation cavity.
[0006] The beneficial effects of the utility model are as follows: the gasket, steel pipe and casing are integrated and fixed as a whole. When the gasket seal fails, the operator only needs to rotate the hand screw. When the hand screw is separated from the installation cavity and taken out, the seal integration can be taken out together without disassembling the remaining parts. Compared with the traditional replacement method, this solution greatly reduces the difficulty of replacing the gasket. It can be quickly replaced without any auxiliary tools, which is more time-saving and labor-saving, and can greatly reduce the workload of after-sales staff in replacing the gasket.
[0007] Furthermore, a through hole matching the diameter of the steel tube is opened in the center of the hand screw, and the lower end of the steel tube extends into the through hole of the hand screw and extends out of the hand screw. The lower end of the steel tube needs to pass through the hand screw and then be connected to the six-way valve on the chromatograph, so that the sample in the injection needle flows through the internal channel of the gasket, the internal cavity of the steel tube, the six-way valve and finally enters the chromatographic column or mass spectrometer.
[0008] Furthermore, the steel pipe includes an integrated steel pipe head and a steel pipe body, the steel pipe body is a cylindrical structure, and the cross-sectional area of the steel pipe head is larger than the cross-sectional area of the steel pipe body; the gasket is a cylindrical structure; the internal cavity shape of the sleeve matches the shape of the gasket and the steel pipe after connection. The cavity of the sleeve has a unidirectional axial limiting effect on the steel pipe. That is, it can limit the downward displacement of the steel pipe, but does not limit the upward displacement of the steel pipe.
[0009] Furthermore, the installation cavity includes a front end of the cavity, a middle end of the cavity and a rear end of the cavity. A step groove with a cross-sectional area larger than the front end of the cavity is provided at the connection between the front end of the cavity and the middle end of the cavity. The upper plane of the steel pipe abuts against the groove surface of the step groove; the threaded portion of the hand screw is threadedly connected to the cavity wall at the rear end of the cavity.
[0010] The beneficial effect of the above technical solution is that the step groove functions as a limit, and cooperates with the hand screw at the rear end to tighten the sleeve and limit the upward movement of the sleeve.
[0011] Furthermore, the front end of the cavity is in a funnel-shaped structure, which plays a guiding role for the injection needle to penetrate into the channel of the gasket, making it easier for the injection needle to penetrate smoothly.
[0012] Furthermore, the sealing channel inside the gasket includes a first channel and a second channel which are connected in sequence; the first channel is a conical structure, the second channel is a cylindrical structure, and the second channel is connected to the internal channel of the steel pipe. The conical first channel can firstly play a guiding role, secondly, it is conducive to the injection needle to form a line seal, and thirdly, the service life of the gasket can be extended by adjusting the downward pressure of the injection needle.
[0013] Furthermore, the hand screw and the sleeve are detachably connected; a boss with external threads is provided at the end of the threaded portion of the hand screw; the sleeve includes a sleeve body and a sleeve tail portion with a cross-sectional area equal to that of the boss, and the sleeve tail portion is provided with external threads; the rotation direction of the threads on the boss is opposite to that of the threads on the threaded portion, and is the same as that of the sleeve tail portion; the outer walls of the boss and the sleeve tail portion are threadedly connected with a connecting sleeve.
[0014] The beneficial effects of the above technical solution are: the boss and the hand screw are integrally formed. The external threads with opposite rotation directions are provided to prevent the hand screw and the connecting sleeve from being loosened when the hand screw is screwed, thereby separating the sleeve from the hand screw. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a cross-sectional schematic diagram of a needle seal assembly;
[0016] Figure 2 A cross-sectional schematic diagram of a sealing integration;
[0017] Figure 3 A cross-sectional schematic diagram of the installation shell.
[0018] Among them, 1. Sealing integration; 11. Gasket; 111. First channel; 112. Second channel; 12. Steel pipe; 121. Steel pipe head; 122. Steel pipe body; 13. Casing; 131. Casing body; 132. Casing tail; 2. Injection needle; 3. Thumb screw; 31. Boss; 4. Mounting shell; 42. Mounting cavity; 421. Front end of cavity; 422. Step groove; 423. Rear end of cavity; 5. Connecting sleeve. DETAILED DESCRIPTION
[0019] The specific implementation methods of the utility model are described below to facilitate technical personnel in this technical field to understand the utility model, but it should be clear that the utility model is not limited to the scope of the specific implementation methods. For ordinary technical personnel in this technical field, as long as various changes are within the spirit and scope of the utility model defined and determined by the attached claims, these changes are obvious, and all utility model creations using the concept of the utility model are protected.
[0020] like Figure 1 As shown, the needle seal assembly of the present solution includes a mounting housing 4 with a mounting cavity 42 formed therein, and a sealing assembly 1 is arranged in the mounting cavity 42. The sealing assembly 1 includes a sleeve 13, a steel pipe 12, and a gasket 11 fixed to the upper plane of the steel pipe 12. The sleeve 13 is sleeved on the outside of the gasket 11 and the steel pipe 12, and the gasket 11 is completely located inside the sleeve 13, and the strength of the sleeve 13 is greater than that of the gasket 11.
[0021] The sleeve 13 can provide additional support and rigidity, so that the gasket 11 is not easily deformed or deformed less when under pressure. When the gasket 11 is under pressure, the sleeve 13 can share part of the load and reduce the deformation of the gasket 11. And the sleeve 13, as an external protective layer, can reduce the external wear of the gasket 11 during use. The gasket 11 is preferably made of PEEK material, and the sleeve 13 is preferably made of AISI 316L material, which has a high yield strength and can effectively reduce the deformation of the gasket 11.
[0022] The lower end of the sleeve 13 is connected with a hand screw 3 that can drive the sleeve 13 to move, and the threaded portion of the hand screw 3 is threadedly connected with the cavity wall of the installation cavity 42. A through hole matching the diameter of the steel tube 12 is opened in the center of the hand screw 3, and the lower end of the steel tube 12 extends into the through hole of the hand screw 3 and extends out of the hand screw 3. The lower end of the steel tube 12 needs to pass through the hand screw 3 and then be connected to the six-way valve on the chromatograph, so that the sample in the injection needle 2 flows through the internal channel of the gasket 11, the internal cavity of the steel tube 12, the six-way valve, and finally enters the chromatographic column or mass spectrometer.
[0023] This solution integrates and fixes the gasket 11, the steel pipe 12 and the sleeve 13 into a whole. When the seal of the gasket 11 fails, the operator only needs to rotate the hand screw 3. When the hand screw 3 is separated from the installation cavity 42 and taken out, the seal integration 1 can be taken out together without disassembling the remaining parts. Compared with the traditional replacement method, this solution greatly reduces the difficulty of replacing the gasket 11. It can be quickly replaced without any auxiliary tools, which is more time-saving and labor-saving, and can greatly reduce the workload of after-sales staff in replacing the gasket 11.
[0024] The steel pipe 12 and the gasket 11 can be fixed by bonding with an adhesive, and the gasket 11 and the wall of the sleeve 13 can be bonded with an adhesive with relatively weak adhesion or pressed with interference fit to prevent the gasket 11 from easily falling off under force. After the sealing assembly 1 is taken out, the operator can directly apply an upward force to the lower end of the steel pipe 12 to push out the gasket 11 without the need for additional auxiliary tools, so that the gasket 11 is exposed. Then separate the gasket 11 and the steel pipe 12 that are fixedly connected. Finally, re-bond the new gasket 11 to the upper end of the steel pipe 12 and then install it back into the sleeve 13.
[0025] In another embodiment, in order to further ensure the stability of the gasket 11 and prevent the gasket 11 from moving, a stronger adhesive can be used to fix the gasket 11 to the inner wall of the steel pipe 12 and the sleeve 13, so it is more difficult to remove the gasket 11 from the sleeve 13. In this case, it is not necessary to remove the gasket 11, but directly replace the entire sealing assembly 1. The sleeve 13 and the hand screw 3 can be connected by welding, strong bonding or other non-detachable connection, and replaced in one piece when replaced, or a detachable connection structure such as a threaded connection can be used without replacing the hand screw 3.
[0026] refer to Figure 2 The steel pipe 12 includes an integrated steel pipe head 121 and a steel pipe body 122. The steel pipe body 122 is a cylindrical structure, and the cross-sectional area of the steel pipe head 121 is larger than the cross-sectional area of the steel pipe body 122. The gasket 11 is a cylindrical structure. The internal cavity shape of the sleeve 13 matches the shape of the gasket 11 and the steel pipe 12 after connection. Since the cross-sectional area of the steel pipe head 121 is larger than the cross-sectional area of the steel pipe body 122, and the cavity shape of the sleeve 13 near the steel pipe 12 matches the steel pipe 12, the cavity of the sleeve 13 has a unidirectional axial limiting effect on the steel pipe 12.
[0027] That is, the steel tube 12 can be limited to move downward, but not to move upward. Therefore, applying a force to the steel tube 12 can push the gasket 11 out, but during the injection operation, the operator inserts the injection needle 2 into the injection port, which actually applies a downward force to the gasket 11. At this time, the steel tube 12 will not be displaced because the wall of the sleeve 13 limits the position of the steel tube head 121.
[0028] refer to Figure 3 The installation cavity 42 includes a cavity front end 421, a cavity middle end and a cavity rear end 423. A step groove 422 with a cross-sectional area larger than that of the cavity front end 421 is provided at the connection between the cavity front end 421 and the cavity middle end. The upper plane of the steel pipe 12 abuts against the groove surface of the step groove 422. The threaded portion of the hand screw 3 is threadedly connected with the cavity wall of the cavity rear end 423. The cavity front end 421 is a funnel-shaped structure. It plays a guiding role for the injection needle 2 to penetrate into the channel of the gasket 11, making it easier for the injection needle 2 to penetrate smoothly.
[0029] The step groove 422 serves as a limiter, and cooperates with the hand screw 3 at the rear end to tighten the sleeve 13, limiting the upward movement of the sleeve 13. When the injection needle 2 is inserted or removed, the injection needle 2 is in close contact with the inside of the gasket 11, and thus indirectly exerts a downward or upward force on the sleeve 13. The step groove 422 can prevent the sleeve 13 from being separated from the hand screw 3 and being taken out of the installation cavity 42.
[0030] Reference again Figure 2 The sealing channel inside the gasket 11 includes a first channel 111 and a second channel 112 which are connected in sequence; the first channel 111 is a conical structure, the second channel 112 is a cylindrical structure, and the second channel 112 is connected to the internal channel of the steel pipe 12. The conical first channel 111 can play a guiding role, is conducive to the formation of a line seal for the injection needle 2, and can extend the service life of the gasket 11 by adjusting the downward pressure of the injection needle 2.
[0031] Specifically, since the injection needle 2 is also conical and its diameter increases from bottom to top, when the inner wall of the gasket 11 is slightly deformed and loosened due to long-term use, the operator can continue to deepen the insertion depth of the injection needle 2, so that the contour of the injection needle 2 with a larger diameter than the original diameter can be re-tightly matched with the sealing channel, thereby extending the service life of the gasket 11 and reducing the replacement frequency of the sealing integration 1.
[0032] In addition, the sealing effect formed by the injection needle 2 at the connection position between the first channel 111 and the second channel 112 is closer to a line seal rather than a surface seal, because the line seal can be sealed along the contour of the injection needle 2 and can better fill the gap between the injection needle 2 and the gasket 11. Therefore, the line seal can usually withstand higher pressure. Therefore, for the injection needle 2, the line seal is better than the surface seal.
[0033] In one embodiment of the utility model, the hand screw 3 and the sleeve 13 are detachably connected; the end of the threaded portion of the hand screw 3 is provided with a boss 31 with external threads; the sleeve 13 includes a sleeve body 131 and a sleeve tail 132 with a cross-sectional area equal to that of the boss 31, and the sleeve tail 132 is provided with external threads. The rotation direction of the thread on the boss 31 is opposite to the rotation direction of the thread on the threaded portion, and is the same as the rotation direction of the sleeve tail 132; the outer wall of the boss 31 and the sleeve tail 132 is threadedly connected with a connecting sleeve 5.
[0034] The boss 31 and the hand screw 3 are integrally formed. The external threads with opposite rotation directions are provided to prevent the hand screw 3 and the connecting sleeve 5 from being loosened when the hand screw 3 is screwed, thereby separating the sleeve 13 from the hand screw 3.
[0035] In summary, this solution integrates the gasket 11 and the steel pipe 12 into an integral sealing assembly 1 through the sleeve 13, and cooperates with the hand-tightened bolt 3, which greatly reduces the difficulty of disassembly and replacement of the needle seal, and can be quickly replaced without any auxiliary tools.
Claims
1. A needle sealing assembly, characterized in that: The invention comprises an installation shell (4) with an installation cavity (42) formed therein, wherein a sealing assembly (1) is arranged in the installation cavity (42); the sealing assembly (1) comprises a sleeve (13), a steel pipe (12) and a gasket (11) fixed to the upper plane of the steel pipe (12); the sleeve (13) is sleeved on the outside of the gasket (11) and the steel pipe (12); the gasket (11) is completely located inside the sleeve (13), and the strength of the sleeve (13) is greater than the strength of the gasket (11); the lower end of the sleeve (13) is connected to a hand screw (3) capable of driving the sleeve (13) to move, and the threaded portion of the hand screw (3) is threadedly connected to the cavity wall of the installation cavity (42).
2. The needle seal assembly according to claim 1, characterized in that: A through hole matching the diameter of the steel pipe (12) is provided at the center of the hand screw (3); the lower end of the steel pipe (12) extends into the through hole of the hand screw (3) and extends out of the hand screw (3).
3. The needle seal assembly according to claim 1, characterized in that: The steel pipe (12) comprises an integrated steel pipe head (121) and a steel pipe body (122); the steel pipe body (122) is a cylindrical structure; the cross-sectional area of the steel pipe head (121) is larger than the cross-sectional area of the steel pipe body (122); the gasket (11) is a cylindrical structure; and the shape of the internal cavity of the sleeve (13) matches the shape of the gasket (11) and the steel pipe (12) after connection.
4. The needle seal assembly according to claim 1, characterized in that: The installation cavity (42) comprises a cavity front end (421), a cavity middle end and a cavity rear end (423); a step groove (422) having a cross-sectional area larger than that of the cavity front end (421) is provided at the connection between the cavity front end (421) and the cavity middle end; the upper plane of the steel pipe (12) abuts against the groove surface of the step groove (422); and the threaded portion of the hand screw (3) is threadedly connected to the cavity wall of the cavity rear end (423).
5. The needle seal assembly according to claim 4, characterized in that: The front end (421) of the cavity is in a funnel-shaped structure.
6. The needle seal assembly according to claim 1, characterized in that: The sealing channel inside the gasket (11) comprises a first channel (111) and a second channel (112) which are connected in sequence; the first channel (111) is a conical structure, the second channel (112) is a cylindrical structure, and the second channel (112) is connected to the internal channel of the steel pipe (12).
7. The needle seal assembly according to claim 1, characterized in that: The hand screw (3) and the sleeve (13) are detachably connected; a boss (31) with external threads is provided at the end of the threaded portion of the hand screw (3); the sleeve (13) comprises a sleeve body (131) and a sleeve tail (132) having a cross-sectional area equal to that of the boss (31), and the sleeve tail (132) is provided with external threads; The rotation direction of the thread on the boss (31) is opposite to that of the thread on the threaded portion and is the same as that of the sleeve tail (132); the outer walls of the boss (31) and the sleeve tail (132) are threadedly connected with a connecting sleeve (5).