Sample injection needle of automatic sample injector

Abstract

The utility model discloses a sample injection needle of an automatic sample injector, which comprises a first joint, an inner needle, an outer needle and a second joint, the inner needle, the outer needle and the second joint are respectively connected with the first joint, the inner needle is communicated with the second joint, the outer needle is fixedly connected with the first joint and sleeved outside the inner needle, and the length of the outer needle is smaller than that of the inner needle; a gap is formed between the outer needle and the inner needle, and a plurality of air holes communicated with the outside are formed in the top of the outer needle. When the sample injection needle disclosed by the utility model punctures a sample bottle, the space in the sample bottle can be communicated with the outside through the gap between the outer needle and the inner needle, so that the negative pressure in the sample bottle is eliminated, and the stability of sample extraction is ensured.

Description

Technical Field

[0001] The utility model relates to an automatic sampling technology of an analytical instrument, in particular to a sampling needle of an automatic sample injector. Background Art

[0002] At present, with the popularity of automatic samplers in the market, more and more automatic samplers are replacing manual samplers. Then the difficulty of sampler design and the fixing method of the sample needle are becoming more and more prominent. The sample needle must meet the reliability of the puncture function of the sample bottle during actual use. However, after the sample needle punctures the sample bottle, the bottle pad is still in a sealed state, which causes negative pressure in the sample bottle after sampling, making sampling difficult. Utility Model Content

[0003] In order to solve the above-mentioned deficiencies in the prior art, the purpose of the utility model is to provide an injection needle for an automatic sampler, which can eliminate the negative pressure in the sample bottle and ensure normal sampling while ensuring reliable puncture.

[0004] The utility model solves the technical problem by adopting the following technical solution: the injection needle of the automatic sampler comprises a first joint and an inner needle, an outer needle and a second joint respectively connected with the first joint, the inner needle is connected with the second joint, the outer needle is fixedly connected with the first joint and is sleeved on the outside of the inner needle, and the length of the outer needle is less than the length of the inner needle;

[0005] There is a gap between the outer needle and the inner needle, and a plurality of air holes communicating with the outside are arranged on the top of the outer needle.

[0006] Optionally, a first connecting portion protruding downward is provided at the lower portion of the first joint, and an outer wall of the first connecting portion is provided with an external thread;

[0007] A connecting seat is fixed on the top of the outer needle, the connecting seat is provided with a first recess matched with the first connecting part, and an internal thread is provided inside the first recess, so that the connecting seat and the first connecting part are threadedly connected.

[0008] Optionally, a second recess is provided on the upper portion of the first joint, and an inner wall of the second recess is provided with an internal thread;

[0009] A second connecting portion protruding downward is provided at the lower portion of the second connector, and an outer wall of the second connecting portion is provided with an external thread, so that the second connector is threadedly connected to the first connector.

[0010] Optionally, a tough annular sealing body is sleeved between the second connector and the top of the inner needle, and the cross-section of the annular sealing body is conical.

[0011] Optionally, the inner wall of the second joint is provided with a conical surface adapted to the top of the annular sealing body.

[0012] Optionally, the second connector is a 1 / 16 needle tube connector.

[0013] By adopting the above technical scheme, when the injection needle of the utility model punctures the sample bottle, the gap between the outer needle and the inner needle can connect the space in the sample bottle with the outside world, thereby eliminating the negative pressure in the sample bottle and ensuring the stability of sample extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0015] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant utility model, rather than to limit the utility model. It is also necessary to explain that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings.

[0016] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0017] In chromatographic experimental analysis, the device that can quantitatively deliver samples into the chromatographic column is called an injector. Injectors are divided into two types: manual injectors and automatic injectors. The automatic injector is an intelligent and automated laboratory analytical instrument. You only need to set the injection parameters and put in the sample to be tested to complete the automatic injection process.

[0018] With the development of chromatography industry, automatic injection has become more and more common, and the frequency of use of automatic samplers has also increased. With the launch of various manufacturers, the competition for automatic samplers has become more and more fierce, and the performance of samplers has gradually improved, with obvious improvements in injection accuracy, injection repeatability, cross contamination, etc. With the launch of various samplers, the difficulties of automatic samplers have become more and more obvious. Among them, the design of the injection needle itself is a big problem. The fixing method of the injection needle must ensure the stability of injection puncture and the stability of positive and negative pressure in the sample bottle during the sample suction process.

[0019] like Figure 1 As shown, the utility model discloses an injection needle of an automatic sampler, which includes a first connector 100, the first connector 100 is used to connect an inner needle 200, an outer needle 300 and a second connector 400, the second connector 400 is used to connect an injection tube to realize the function of transporting samples. In one embodiment of the utility model, the second connector 400 can adopt a 1 / 16 needle tube connector.

[0020] In the present invention, the inner needle 200 is connected to the second connector 400. For example, when connecting the inner needle 200 to the second connector 400, the end of the inner needle 200 can be inserted into the second connector 400, and then the inner needle 200 can be locked. In addition, the outer needle 300 is fixedly connected to the first connector 100, and the outer needle 300 is sleeved on the outside of the inner needle 200, so that there is a gap between the outer needle 300 and the inner needle 200. At the same time, the length of the outer needle 300 is shorter than that of the inner needle 200, and the top of the outer needle 300 is provided with a plurality of air holes connected to the outside, so as to connect the gap to the outside.

[0021] Specifically, in order to facilitate the connection of the outer needle 300, a first connecting part 110 protruding downward may be provided at the lower part of the first joint 100, and the outer wall of the first connecting part 110 may be provided with an external thread; at the same time, a connecting seat 310 is fixed on the top of the outer needle 300, and the connecting seat 310 is provided with a first recess adapted to the first connecting part 110, and an internal thread is provided inside the first recess, so that the connecting seat 310 and the first connecting part 110 are threadedly connected.

[0022] Similarly, a second recess may be provided at the upper portion of the first joint 110, and an inner wall of the second recess may be provided with an internal thread; at the same time, a second connection portion 410 protruding downward may be provided at the lower portion of the second joint 400, and an outer wall of the second connection portion 410 may be provided with an external thread, so that the second joint 400 is threadedly connected to the first joint 100.

[0023] In order to lock the inner needle 200, a tough annular sealing body 500 may be sleeved between the second joint 400 and the top of the inner needle 200. The cross section of the annular sealing body 500 is conical, and the inner wall of the second joint 400 is provided with a conical surface adapted to the top of the annular sealing body 500. With this solution, when the second joint 400 is tightened, the conical surface of the second connecting part 410 squeezes the annular sealing body 500, and the annular sealing body 500 is tough, so the inner needle 200 is locked when the annular sealing body 500 is contracted, thereby achieving the sealing and fixation of the inner needle 200.

[0024] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the utility model. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) by each other to form a technical solution.

[0025] Except for the technical features described in the specification, the other technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present utility model, the other technical features will not be described in detail here.

Claims

1. An injection needle for an automatic sampler, characterized in that: It includes a first connector and an inner needle, an outer needle and a second connector respectively connected to the first connector, the inner needle is connected to the second connector, the outer needle is fixedly connected to the first connector and is sleeved on the outside of the inner needle, and the length of the outer needle is shorter than that of the inner needle; There is a gap between the outer needle and the inner needle, and a plurality of air holes communicating with the outside are arranged on the top of the outer needle.

2. The injection needle of the automatic sampler according to claim 1, characterized in that: A first connecting portion protruding downward is provided at the lower part of the first joint, and an outer wall of the first connecting portion is provided with an external thread; A connecting seat is fixed on the top of the outer needle, the connecting seat is provided with a first recess matched with the first connecting part, and an internal thread is provided inside the first recess, so that the connecting seat and the first connecting part are threadedly connected.

3. The injection needle of the automatic sampler according to claim 1, characterized in that: A second recess is provided on the upper portion of the first joint, and an inner wall of the second recess is provided with an internal thread; A second connecting portion protruding downward is provided at the lower portion of the second connector, and an outer wall of the second connecting portion is provided with an external thread, so that the second connector is threadedly connected to the first connector.

4. The injection needle of the automatic sampler according to claim 3, characterized in that: A tough annular sealing body is sleeved between the second connector and the top of the inner needle, and the cross section of the annular sealing body is conical.

5. The injection needle of the automatic sampler according to claim 4, characterized in that: The inner wall of the second joint is provided with a conical surface matched with the top of the annular sealing body.

6. The injection needle of the automatic sampler according to claim 1, characterized in that: The second connector is a 1 / 16 needle tube connector.

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