Liquid chromatograph sample injector for food and medicine detection

Abstract

The utility model relates to the technical field of liquid detection equipment, and discloses a liquid chromatograph sample injector for food and medicine detection, which comprises a sample injector main body, a sample injection pipe arranged in the sample injector main body and a sample outlet arranged at the bottom of the sample injection pipe and communicated with a plurality of liquid storage cavities, a cleaning cavity used for storing cleaning liquid is formed between every two adjacent liquid storage cavities, and a cleaning opening communicated with the cleaning cavity is further formed in the bottom of the sample injection pipe. After the sample discharging is finished, the next movement of the piston enables the cleaning liquid to enter the conveying pipe and the sample discharging pipe, so that the conveying pipe and the sample discharging pipe can be cleaned, the cleanliness of the sample discharging pipe and the conveying pipe is ensured, and the problem of inaccurate subsequent detection result caused by mixing of different liquids to be detected is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid detection equipment, in particular to a liquid chromatograph sample injector for food and drug detection. Background Art

[0002] Chromatograph is a device used for chromatographic separation and analysis. It includes a sampling system, a detection system, a recording and data processing system, a temperature control system, and a mobile phase control system. Modern chromatographs have the characteristics of stability, sensitivity, versatility, and a high degree of automation. There are gas chromatographs, liquid chromatographs, and gel chromatographs. These chromatographs are widely used for the analysis of certain contents of chemical products and polymer materials. Gel chromatography can also determine the molecular weight and distribution of polymer materials. Liquid chromatographs need to be supplemented with solvents when working.

[0003] The existing liquid chromatograph cannot quantify the liquid injected into the chromatograph when delivering liquid, so the staff still needs to use a quantitative sampler to take samples. This can easily lead to too high or too low liquid content during testing, resulting in inaccurate test results. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a liquid chromatograph sample injector for food and drug testing, aiming to alleviate the above-mentioned problems at least to a certain extent.

[0005] The above technical objectives of the utility model are achieved through the following technical solutions:

[0006] A liquid chromatograph sample injector for food and drug testing, comprising:

[0007] Injector body;

[0008] A sample injection tube rotatably arranged in the sample injector body, wherein the sample injection tube is provided with a plurality of liquid storage cavities for storing the liquid to be detected, and a cleaning cavity for storing a cleaning liquid is provided between each two adjacent liquid storage cavities;

[0009] A sample outlet is provided at the bottom of the sample injection tube and communicates with the liquid storage cavity. A cleaning port is also provided at the bottom of the sample injection tube and communicates with the cleaning cavity.

[0010] A sample outlet tube provided at the bottom of the sample injector body;

[0011] A delivery tube provided between the injector body and the injection tube;

[0012] A plurality of pistons are arranged in the injector body, wherein each of the liquid storage chambers and each of the cleaning chambers is provided with a piston;

[0013] The sampling component is arranged between the sample injector body and the sampling tube, and the sampling component drives the piston to move up and down. When the sampling component drives the piston upward, the sampling tube rotates a preset angle.

[0014] Preferably, the injection component includes a screw rod rotatably connected to the injector body, a movable frame slidably connected to the injection tube is threadedly connected to the screw rod, a sliding frame is provided on the movable frame, and the piston is connected to the bottom of the sliding frame.

[0015] Preferably, a baffle is provided at one end of the delivery tube located in the sample outlet tube, a closed tube is connected to one side of the baffle, a plurality of connection ports are opened on the outer wall of the closed tube, and a first spring is connected between the baffle and the sample outlet tube.

[0016] Preferably, a connecting rod is slidably connected to the bottom of the sliding frame, and a second spring is connected between the sliding frame and the piston.

[0017] Preferably, a bracket is connected to the top of the sampler body, a rotating frame connected to the sample injection tube is rotatably connected inside the bracket, the rotating frame and the bracket are interference fit, a turntable is rotatably connected inside the rotating frame, a plurality of pawls are connected to the outer wall of the turntable, a return spring is arranged between each pawl and the turntable, a ratchet matching with the pawl is arranged on the inner wall of the rotating frame, a limit rod is slidably connected to the top of the sliding frame, and a third spring is connected between the limit rod and the sliding frame.

[0018] Preferably, a motor is connected to the inner bottom surface of the injector body, a driving shaft of the motor is connected to the screw rod, a plurality of liquid inlet pipes are connected to the outside of the injector body, and a connecting port corresponding to the liquid inlet pipe is opened on one side of the liquid storage chamber and the cleaning chamber.

[0019] In summary, the utility model mainly has the following beneficial effects:

[0020] When the utility model is used, the operator can pour the liquid to be tested into the multiple liquid storage chambers opened in the sample injection tube. The multiple liquid storage chambers can respectively store different liquids to be tested. At the same time, the cleaning liquid used to clean the delivery tube and the sample outlet tube can be poured into the cleaning chamber. The sample outlet at the bottom of one of the liquid storage chambers can correspond to the position of the delivery tube. The sample injection component can be used to drive the piston downward. The downward movement of the piston can allow the liquid in the liquid storage chamber or the cleaning chamber connected to the delivery tube to enter the sample outlet tube through the delivery tube. The fixed stroke of the piston can ensure that the amount of liquid entering the sample outlet tube is fixed, so that The invention can achieve the purpose of quantitatively sampling the liquid to be tested. At the same time, after the sampling is completed, the cleaning liquid enters the delivery tube and the sample outlet tube at the next movement of the piston, and the delivery tube and the sample outlet tube can be cleaned, thereby ensuring the cleanliness of the sample outlet tube and the delivery tube, and avoiding the problem of inaccurate subsequent test results caused by the mixing of different liquids to be tested. Compared with the sampling equipment in the prior art, the present application solves the problem that the staff needs to use a quantitative sampler for sampling, which may easily lead to too high or too low liquid content during the detection work, thereby leading to inaccurate test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0022] Figure 2 It is a schematic diagram of the structure of the sample injection tube of the utility model;

[0023] Figure 3 It is a schematic diagram of the structure of the delivery pipe of the utility model.

[0024] Reference numerals:

[0025] 100, injector body; 101, injection tube; 102, liquid storage chamber; 103, cleaning chamber; 104, sample outlet; 105, cleaning port; 106, sample outlet tube; 107, delivery tube; 108, piston;

[0026] 200, screw rod; 201, moving frame; 202, sliding frame; 203, baffle; 204, closing tube; 205, connecting port; 206, first spring; 207, connecting rod; 208, second spring;

[0027] 300, bracket; 301, rotating frame; 302, turntable; 303, pawl; 304, ratchet; 305, limit rod; 306, third spring; 307, motor; 308, liquid inlet pipe; 309, connecting port. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] refer to Figure 1-Figure 3 A liquid chromatograph sample injector for food and drug detection includes a sample injector body 100, a sample injection tube 101, a sample outlet 104, a sample outlet tube 106, a delivery tube 107, a plurality of pistons 108 and a sample injection component. The sample injection tube 101 is rotatably arranged in the sample injector body 100. The sample injection tube 101 is provided with a plurality of liquid storage chambers 102 for storing liquid to be detected. A cleaning chamber 103 for storing a cleaning liquid is provided between each two adjacent liquid storage chambers 102. The sample outlet 104 is provided at the bottom of the sample injection tube 101 and communicates with the liquid storage chamber 102. The bottom of the sample injection tube 101 is also provided with a cleaning chamber 103 for storing a cleaning liquid. A connected cleaning port 105 and a sample outlet tube 106 are arranged at the bottom of the sampler body 100, and a delivery tube 107 is arranged between the sample outlet tube 106 and the sample injection tube 101. As the sample injection tube 101 rotates, each sample outlet 104 and each cleaning port 105 are alternately connected to the upper end of the delivery tube 107. A piston 108 is slidably installed in each liquid storage cavity 102 and each cleaning cavity 103. The sample injection component is arranged between the sampler body 100 and the sample injection tube 101. The sample injection component is used to drive each piston 108 to move up and down respectively. When the sample injection component drives the piston 108 to move upward, the sample injection tube 101 rotates a preset angle.

[0030] When not in communication with the delivery tube 107 , the sample outlet 104 and the cleaning port 105 are blocked by the bottom of the sample inlet tube 101 .

[0031] By setting the sample injection tube 101, when in use, the operator can pour the liquid tube to be tested into the multiple liquid storage chambers 102 opened in the sample injection tube 101. The multiple liquid storage chambers 102 can respectively store different liquids to be tested. At the same time, the cleaning liquid used to clean the delivery tube 107 and the sample outlet tube 106 can be poured into the cleaning chamber 103. The sample outlet 104 at the bottom of one of the liquid storage chambers 102 can correspond to the position of the delivery tube 107. The position of the piston 108 can be moved downward by the sample injection component. The piston 108 moves downward to make the liquid in the liquid storage chamber 102 or the cleaning port 105 connected with the delivery tube 107 enter into the sample outlet tube 106. The piston 108 has a fixed stroke, which can ensure that the liquid enters the sample outlet tube 106. The amount of liquid in tube 106 is fixed, so that the purpose of quantitative sampling of the liquid to be tested can be achieved. At the same time, after the sampling is completed, the next movement of piston 108, the cleaning liquid enters the delivery tube 107 and the sample outlet tube 106, and the delivery tube 107 and the sample outlet tube 106 can be cleaned, thereby ensuring the cleanliness of the sample outlet tube 106 and the delivery tube 107, avoiding the mixing of different liquids to be tested and causing inaccurate subsequent test results. Compared with the sampling equipment in the prior art, the present application solves the problem that the staff needs to use a quantitative sampler for sampling, which is easy to cause the liquid content to be too high or too low during the detection work, thereby causing inaccurate test results.

[0032] As a further feature of the present invention, the injection component includes a screw rod 200 rotatably connected to the injector body 100, and a movable frame 201 slidably connected to the injection tube 101 is threadedly connected to the screw rod 200, and a sliding frame 202 is provided on the movable frame 201, and the piston 108 is connected to the bottom of the sliding frame 202.

[0033] By setting the screw rod 200, during application, the operator can rotate the screw rod 200. The rotation of the screw rod 200 can push the movable frame 201 downward through the force of the thread. The reverse rotation of the screw rod 200 can reset the movable frame 201 upward, thereby realizing the up and down movement of the piston 108.

[0034] As a further feature of the present invention, a baffle 203 is provided at one end of the delivery tube 107 located inside the sample outlet tube 106, a closed tube 204 is connected to one side of the baffle 203, a plurality of connection ports 205 are provided on the outer wall of the closed tube 204, and a first spring 206 is connected between the baffle 203 and the delivery tube 107.

[0035] The first spring 206 can limit the position of the baffle 203, and the baffle 203 forms a one-way valve. When the piston 108 moves downward, positive pressure can be generated in the liquid storage chamber 102 or the cleaning chamber 103. The positive pressure can cause the baffle 203 to move, and the liquid in the delivery tube 107 can flow out through the connecting port 205, thereby achieving the purpose of delivering the liquid to the sample outlet tube 106 when the piston 108 moves downward. In this embodiment, the two ends of the first spring 206 are fixedly connected to the baffle 203 and the delivery tube 107 respectively. Through the restriction of the first spring 206, the sealing tube 204 can be prevented from separating from the delivery tube 107.

[0036] As a further feature of the present invention, a connecting rod 207 is slidably connected to the bottom of the sliding frame 202 , and a second spring 208 is connected between the sliding frame 202 and the piston 108 .

[0037] By setting the connecting rod 207, when the movable frame 201 and the sliding frame 202 move downward and drive the piston 108 to move downward, the piston 108 in the liquid storage chamber 102 or the cleaning chamber 103 connected to the delivery pipe 107 can move downward, and the remaining liquid storage chambers 102 or the cleaning chambers 103 are in a closed state. Therefore, the piston 108 is stationary, and only the corresponding second spring 208 is compressed, so that only the liquid in the cavity connected to the delivery pipe 107 is pressed into the delivery pipe 107.

[0038] As a further feature of the present invention, a bracket 300 is connected to the top of the sample injector body 100, and a rotating frame 301 connected to the sample injection tube 101 is rotatably connected in the bracket 300, and the rotating frame 301 and the bracket 300 are interference fit, and a turntable 302 is rotatably connected in the rotating frame 301, and a plurality of ratchet pawls 303 are connected to the outer wall of the turntable 302, and a return spring is arranged between each ratchet pawl 303 and the turntable 302, and the inner wall of the rotating frame 301 is provided with a ratchet 304 matching with the ratchet pawl 303, and the ratchet pawl 303, the ratchet 304 and the return spring are combined into a ratchet mechanism, so that one-way transmission is realized between the turntable 302 and the rotating frame 301, and the top of the sliding frame 202 is slidably connected to the limit rod 305, and a limit disk is arranged on the top of the limit rod 305, and a third spring 306 is connected between the limit rod 305 and the sliding frame 202, and the upper end of the third spring 306 is supported on the limit disk.

[0039] When the screw rod 200 rotates to allow the movable frame 201 to move downward, due to the interference fit between the rotating frame 301 and the bracket 300, the rotation of the rotating frame 301 requires a sufficiently large force, which can overcome the elastic force of the reset spring, the pawl 303 contracts, and the turntable 302 rotates idly in the rotating frame 301, thereby achieving the purpose of allowing the movable frame 201 and the sliding frame 202 to drive the piston 108 to move downward. When the screw rod 200 rotates in the opposite direction to allow the movable frame 201 and the sliding frame 202 to reset upward to the preset position, the limit plate at the top of the limit rod 305 is supported on the bottom of the rotating frame 301 under the elastic force of the third spring 306, and cooperates with the pawl 303 and the ratchet 304 to allow the rotating frame 301 to rotate synchronously with the turntable 302, thereby achieving the purpose of allowing the sample injection tube 101 to rotate by a preset angle.

[0040] The limiting rod 305 and the third spring 306 may not be provided.

[0041] As a further feature of the present invention, the inner bottom surface of the injector body 100 is connected to a motor 307, the drive shaft of the motor 307 is connected to the screw rod 200, the outside of the injector body 100 is connected to a plurality of liquid inlet tubes 308, and a connecting port 309 corresponding to the liquid inlet tube 308 is opened on one side of the liquid storage chamber 102 and the cleaning chamber 103.

[0042] By providing the motor 307 , the rotation of the driving shaft of the motor 307 can provide driving force for the rotation of the screw rod 200 .

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A liquid chromatograph sample injector for food and drug testing, characterized in that: include: Injector body (100); A sampling tube (101) rotatably disposed in the sampler body (100), wherein the sampling tube (101) is provided with a plurality of liquid storage cavities (102) for storing liquid to be detected, and a cleaning cavity (103) for storing a cleaning liquid is provided between every two adjacent liquid storage cavities (102); A sample outlet (104) is provided at the bottom of the sample injection tube (101) and is in communication with the liquid storage chamber (102); a cleaning port (105) is also provided at the bottom of the sample injection tube (101) and is in communication with the cleaning chamber (103); A sample outlet tube (106) provided at the bottom of the sample injector body (100); A delivery tube (107) disposed between the sample injector body (100) and the sample injection tube (101); A plurality of pistons (108) disposed in the injector body (100), wherein each of the liquid storage chambers (102) and each of the cleaning chambers (103) is provided with a piston (108); An injection component is provided between the injector body (100) and the injection tube (101), wherein the injection component drives the piston (108) to move up and down, and when the injection component drives the piston (108) upward, the injection tube (101) is rotated by a preset angle.

2. The liquid chromatograph sample injector for food and drug testing according to claim 1, characterized in that: The injection component comprises a screw rod (200) rotatably connected to the injector body (100); a movable frame (201) slidably connected to the injection tube (101) is threadedly connected to the screw rod (200); a sliding frame (202) is provided on the movable frame (201); and the piston (108) is connected to the bottom of the sliding frame (202).

3. The liquid chromatograph sample injector for food and drug testing according to claim 1, characterized in that: A baffle (203) is provided at one end of the delivery tube (107) located inside the sample outlet tube (106); a closed tube (204) is connected to one side of the baffle (203); a plurality of connection ports (205) are provided on the outer wall of the closed tube (204); and a first spring (206) is connected between the baffle (203) and the sample outlet tube (106).

4. The liquid chromatograph sample injector for food and drug testing according to claim 2, characterized in that: A connecting rod (207) is slidably connected to the bottom of the sliding frame (202), and a second spring (208) is connected between the sliding frame (202) and the piston (108).

5. The liquid chromatograph sample injector for food and drug testing according to claim 2, characterized in that: The top of the sample injector body (100) is connected to a bracket (300), a rotating frame (301) connected to the sample injection tube (101) is rotatably connected inside the bracket (300), the rotating frame (301) and the bracket (300) are interference fit, a turntable (302) is rotatably connected inside the rotating frame (301), a plurality of ratchets (303) are connected to the outer wall of the turntable (302), a return spring is arranged between each ratchets (303) and the turntable (302), a ratchet (304) matching with the ratchets (303) is arranged on the inner wall of the rotating frame (301), a limit rod (305) is slidably connected to the top of the sliding frame (202), and a third spring (306) is connected between the limit rod (305) and the sliding frame (202).

6. The liquid chromatograph sample injector for food and drug testing according to claim 2, characterized in that: A motor (307) is connected to the inner bottom surface of the sample injector body (100), and a drive shaft of the motor (307) is connected to the screw rod (200). A plurality of liquid inlet pipes (308) are connected to the outside of the sample injector body (100), and a communication port (309) corresponding to the liquid inlet pipe (308) is provided on one side of the liquid storage chamber (102) and the cleaning chamber (103).

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