A test tube clamping mechanism for a micro-droplet PCR instrument

Abstract

The application discloses a test tube clamping mechanism for a droplet PCR instrument, and relates to the technical field of biological and medical equipment.The test tube clamping mechanism comprises a support shell and a sealing cover hingedly arranged on the support shell, a mounting plate is arranged in the support shell, a placing hole for placing a test tube is formed in the mounting plate, a clamping assembly for adapting to the size of most test tubes is arranged in the placing hole, and a clamping plate for fixing the test tube is arranged at the moving end of the clamping assembly.The application realizes automatic adaptation and stable clamping of most diameter test tubes through the use of the inclined sliding groove, the slide column and the clamping plate.When the test tube is placed, the bottom extrusion bearing plate makes the arc block move downward, the inclined sliding groove in the arc block extrudes the slide column through the inclined surface, the slide column drives the clamping plate to move horizontally, the slope of the inclined sliding groove is fixed, the moving distance of the bearing plate and the moving distance of the clamping plate form a linear relationship, most diameter test tubes are automatically adapted, and the clamping force is uniform.

Description

Technical Field

[0001] This application relates to the field of biomedical equipment technology, and in particular to a test tube clamping mechanism for a droplet PCR instrument. Background Technology

[0002] Droplet digital PCR (ddPCR), as a third-generation PCR technology, has shown significant advantages in precision medicine, pathogen detection, and gene expression analysis due to its ability to achieve absolute quantification of nucleic acid molecules. The core of this technology lies in dividing the reaction system into tens of thousands of nano-level droplets and reading the fluorescence signal of each droplet after PCR thermal cycling.

[0003] In use, traditional test tube placement plates are mostly designed with fixed well diameters. However, PCR test tubes from different manufacturers on the market vary in diameter, making it difficult to quickly adapt to the size of most test tubes. Often, it is necessary to replace the placement plate with one of the corresponding well diameters in order to complete gene analysis and reading. Utility Model Content

[0004] To address the issue that the placement plate cannot accommodate most test tube sizes, this application provides a test tube clamping mechanism for a microdroplet PCR instrument.

[0005] The test tube clamping mechanism for a droplet PCR instrument provided in this application adopts the following technical solution:

[0006] A test tube clamping mechanism for a microdroplet PCR instrument includes a support housing and a sealing cover hinged to the support housing. An installation plate is provided inside the support housing. The installation plate has a placement hole for placing test tubes. A clamping component for accommodating most test tube sizes is provided inside the placement hole. A clamping plate for fixing the test tubes is provided at the movable end of the clamping component.

[0007] By adopting the above technical solution, the supporting shell and the hinged sealing cover constitute a protective shell. The placement holes on the mounting plate are used to place test tubes. The built-in clamping component fixes test tubes of various sizes through the moving end clamp. The whole structure forms the basic frame for clamping test tubes of the microdroplet PCR instrument. The downward movement distance of the clamping component and the movement distance of the clamp are linearly related. The thicker the test tube, the deeper the downward pressure, and the greater the inward movement distance of the clamp, thereby automatically adapting to test tubes of most diameters and ensuring uniform clamping force.

[0008] Preferably, the sealing cap has a circular hole corresponding to the placement hole for placing the test tube, and a pull ring is fixedly provided on the sealing cap.

[0009] By adopting the above technical solution, the round hole on the sealing cap corresponds to the placement hole to allow the test tube to be inserted vertically, and the fixed pull ring makes it easy for users to quickly open and close the sealing cap, improving the convenience of operation.

[0010] Preferably, a rubber pad for contacting the test tube is fixedly provided on the clamp.

[0011] By adopting the above technical solution, the rubber pad protects the test tube surface through flexible contact, while the high coefficient of friction of rubber enhances the clamping stability and prevents hard materials from scratching the test tube or causing sample leakage.

[0012] Preferably, the clamping assembly includes a support plate slidably disposed with a placement hole, a rotating plate rotatably disposed on the support plate, a return spring fixedly disposed between the rotating plate and the placement hole, connecting rods arranged in a circumferential array fixedly disposed on the support plate, a second sliding groove slidably connected to the connecting rods being opened in the placement hole, the connecting rods realizing the translational clamping of the test tube by the clamping plate through a reversing structure, and an arc groove adapted to the size of the connecting rods being opened on the second sliding groove.

[0013] By adopting the above technical solution, in the clamping assembly, the bearing plate that is slidably set with the placement hole achieves elastic pressing and reset through a rotating plate and a return spring that are rotatably connected. The connecting rods in the circumferential array slide in the second slide groove and drive the clamping plate to move and clamp through a reversing structure. The arc groove on the second slide groove provides a mechanical locking point to limit the position of the connecting rod, ensuring that the clamping force is adjustable and preventing loosening.

[0014] Preferably, the reversing structure includes a cylindrical groove formed in the mounting plate, and a circular array of arc blocks slidably disposed in the cylindrical groove. The arc blocks are fixedly connected to the connecting rod. A first sliding groove is formed on the side of the arc block near the clamping plate. An oblique sliding groove is formed in the first sliding groove. An arc groove extending into the cylindrical groove is formed in the placement hole. A sliding column fixedly connected to the clamping plate is slidably disposed in the arc groove. A limiting ring plate located in the oblique sliding groove is fixedly disposed on the sliding column.

[0015] By adopting the above technical solution, the reversing structure accommodates the slidably set arc block through the cylindrical groove in the mounting plate. The arc block is fixedly connected to the connecting rod. The inclined groove in its first sliding groove cooperates with the limiting ring plate on the sliding column to convert the vertical movement of the bearing plate into the horizontal clamping movement of the clamping plate. The arc groove guides the sliding column to slide stably, realizing automatic adaptation to the difference in test tube diameter.

[0016] Preferably, the second groove is vertical.

[0017] By adopting the above technical solution, the second slide is designed vertically to ensure that the connecting rod slides only in the vertical direction, avoiding horizontal offset from affecting the clamping accuracy. At the same time, it forms a straight locking path with the vertical array distribution of the arc groove two, enhancing the structural stability.

[0018] Preferably, the second arc groove is distributed in a long linear array along the second slide groove, and the second arc groove has the same size as the first arc groove.

[0019] By adopting the above technical solution, the second arc groove is linearly arrayed along the second slide groove and has the same size as the first arc groove, forming a multi-level locking position. The user can select the corresponding locking position according to the thickness of the test tube, and make the connecting rod lock into the second arc groove by finely adjusting the tube angle, so as to achieve precise control of clamping force and position.

[0020] Preferably, the dimensions of the limiting ring plate are adapted to the dimensions of the inclined slide groove.

[0021] By adopting the above technical solution, the size of the limiting ring plate is matched with the inclined slide groove, ensuring that the sliding column slides stably in the inclined slide groove without coming out. At the same time, the motion is transmitted through the inclined surface extrusion, which efficiently converts the vertical displacement of the bearing plate into the horizontal clamping displacement of the clamping plate, thereby improving the motion transmission efficiency.

[0022] In summary, this application includes at least one of the following beneficial technical effects:

[0023] 1. Through the linkage structure of the inclined slide, sliding column, and clamping plate, automatic adaptation and stable clamping of test tubes of most diameters are achieved. When the test tube is placed, the bottom pressure bearing plate causes the arc block to move down. The inclined slide inside the arc block presses the sliding column through the inclined surface, causing the sliding column to drive the clamping plate to move horizontally. Since the slope of the inclined slide is fixed, the downward movement distance of the bearing plate (determined by the diameter of the test tube) and the movement distance of the clamping plate form a linear relationship. The thicker the test tube, the deeper the pressure, and the greater the inward movement distance of the clamping plate, thus automatically adapting to test tubes of most diameters and ensuring uniform clamping force.

[0024] 2. The mechanical self-locking of the clamping state is achieved through the cooperation of the connecting rod and the second arc groove, which prevents loosening during thermal cycling. After the test tube is clamped to the target position, the user can finely adjust the tube angle so that the connecting rod is locked into the arc groove of the corresponding height. The linear array design of the second arc groove allows different clamping positions to be selected according to the diameter of the test tube, which not only restricts the axial movement of the test tube, but also fixes the clamping force through mechanical buckling, avoiding loosening of the test tube due to vibration or operation.

[0025] 3. The use of clamping components simplifies the installation and fixing process of test tubes. Users only need to place the test tube vertically into the placement hole, and the mechanism will automatically clamp it. If locking is required, a slight rotation of the test tube will complete the mechanical locking. The operation is convenient and requires no tools or additional accessories. At the same time, the rubber pad at the end of the clamping plate provides sufficient friction while avoiding hard contact, effectively protecting the test tube from scratches or cracks. Attached Figure Description

[0026] Figure 1 This is a three-dimensional schematic diagram of the overall structure of this application;

[0027] Figure 2 This is a top view of the overall structure of this application;

[0028] Figure 3 This is a schematic diagram of the placement hole structure in this application;

[0029] Figure 4 for Figure 3 Enlarged structural diagram at point A in the middle;

[0030] Figure 5 This is a schematic diagram of the clamping component of this application;

[0031] Figure 6 This is a partial structural cross-sectional view of the clamping component of this application;

[0032] Figure 7 for Figure 6 Enlarged structural diagram at point B.

[0033] Reference numerals: 1. Support housing; 2. Sealing cover; 21. Pull ring; 22. Round hole; 3. Mounting plate; 4. Placement hole;

[0034] 5. Clamping assembly; 51. Bearing plate; 52. Rotating plate; 53. Return spring; 54. Cylindrical groove; 55. Arc block; 56. First slide groove; 57. Inclined slide groove; 58. Sliding column; 59. Limiting ring plate; 510. Arc groove one; 511. Connecting rod; 512. Second slide groove; 513. Arc groove two; 6. Clamping plate; 61. Rubber pad. Detailed Implementation

[0035] The following is in conjunction with the appendix Figures 1-7 This application will be described in further detail.

[0036] This application discloses a test tube clamping mechanism for a droplet PCR instrument.

[0037] Reference Figures 1 to 7A test tube clamping mechanism for a droplet PCR instrument includes a support shell 1 and a sealing cover 2 hinged to the support shell 1. The top inner side of the support shell 1 is fixed to a mounting plate 3. A placement hole 4 is opened on the upper surface of the mounting plate 3 for placing test tubes. A clamping component 5 is provided in the placement hole 4 to accommodate the size of most test tubes. Four clamping plates 6 are provided on the moving end of the clamping component 5 to fix the test tubes. A circular hole 22 is opened on the lower surface of the sealing cover 2, and the position of the circular hole 22 corresponds to the position of the placement hole 4 to accommodate the top of the test tube. The outer side of the sealing cover 2 is fixed to both ends of a pull ring 21. The sides of the four clamping plates 6 that are close to each other are fixed to rubber pads 61. The rubber pads 61 are used to contact the test tubes. The rubber pads 61 are made of medical grade or high-purity peroxide vulcanized silicone rubber, which completely covers all temperature points of PCR and has stable performance under high and low temperature cycling. The size of the circular hole 22 is designed to accommodate the height and size of most test tubes.

[0038] In use, the user first opens the hinged sealing cap 2 through the pull ring 21, exposing the placement hole 4 on the mounting plate 3. The PCR tube is then vertically inserted through the top opening of the placement hole 4. The rubber pad 61 on the clamping plate 6 is in its initial position, waiting for the tube to be inserted. During the insertion of the placement hole 4, the tube is held by the clamping component 5. After the user rotates the tube, the position is locked. Then, the sealing cap 2 is closed to complete the initial positioning and sealing preparation of all the tubes. The preferred hardness of the silicone rubber is Shore A hardness of 65±5. This hardness value is similar to that of a car tire tread, providing sufficient hardness to transmit clamping force while retaining sufficient elasticity. It can increase the contact area through slight deformation without damaging the thin-walled PCR tube, providing stable and reliable friction.

[0039] Reference Figures 5 to 7The clamping assembly 5 includes a support plate 51 slidably disposed with the placement hole 4. The center of the support plate 51 is recessed for placing the bottom end of the test tube. The bottom end of the support plate 51 is rotatably connected to the rotating plate 52 on the same axis. The lower surface of the rotating plate 52 is fixed to the top end of the return spring 53, and the bottom end of the return spring 53 is fixed to the bottom of the placement hole 4. The outer surface of the support plate 51 is fixed to four connecting rods 511, which are arranged in a circular array around the center of the support plate 51. A second sliding groove 512 is formed on the inner arc of the placement hole 4. The second sliding groove 512 is vertical and limits the movement of the connecting rods 511. The outer wall of the connecting rod 511 is slidably connected to the second slide groove 512, and the size of the connecting rod 511 is adapted to the size of the second slide groove 512. The connecting rod 511 realizes the translational clamping of the test tube by the clamping plate 6 through the reversing structure. At least one arc groove 513 is opened on the inner side of the second slide groove 512. The position and number of arc grooves 513 are designed according to the diameter of most test tubes. The size of the arc groove 513 is adapted to the size of the connecting rod 511 to facilitate the connecting rod 511 to enter the interior of the arc groove 513. The arc grooves 513 are distributed in a long linear array along the second slide groove 512.

[0040] In the initial state, the connecting rod 511 is located at the top of the second slide groove 512, and the rubber pad 61 does not contact the test tube. As the test tube moves downward into the placement hole 4, its bottom presses on the support plate 51 and overcomes the elastic force of the return spring 53, pushing the support plate 51 to slide downward. The support plate 51 drives the connecting rod 511 to slide downward along the vertical second slide groove 512. The downward movement of the connecting rod 511 will activate the reversing structure connected to it, and finally drive the clamping plate 6 to move towards the center, tightening the clamping of the test tube. The larger the diameter of the test tube, the longer the downward stroke of the support plate 51. After the mechanism is converted, the distance that the clamping plate 6 moves inward is also greater, thereby realizing automatic adaptive clamping from thin tube to thick tube.

[0041] When the test tube can no longer move down, indicating it is fully clamped, the user simply needs to gently rotate the test tube in a small arc. This rotation will cause the support plate 51 and connecting rod 511 to rotate together, allowing the connecting rod 511 to slide from the vertical second slide groove 512 into the aligned arc groove 513. Since the arc groove 513 is a horizontal locking position, it effectively locks the entire mechanism in the vertical direction, preventing it from rebounding during vibration or thermal cycling, and ensuring the long-term stability of the clamping force. The connection point between the rotating plate 52 and the support plate 51 allows the support plate 51 and clamping plate 6 to rotate along with the user when rotating the test tube to lock it, but this torsional force will not be transmitted to the return spring 53, thus avoiding unnecessary torsional deformation and fatigue damage to the return spring 53.

[0042] Reference Figures 5 to 7The reversing structure includes a cylindrical groove 54 formed in the mounting plate 3. The inner wall of the cylindrical groove 54 is slidably disposed with the outer wall of four arc blocks 55. The four arc blocks 55 are positioned corresponding to the connecting rod 511. The end of the connecting rod 511 away from the rotating plate 52 extends into the interior of the cylindrical groove 54. The lower surface of the arc blocks 55 is fixed to the top end of the connecting rod 511. A first sliding groove 56 is formed on the arc block 55. The first sliding groove 56 is located on the side of the arc block 55 closest to the clamping plate 6. An inclined sliding groove 57 is formed on the side of the first sliding groove 56 away from the clamping plate 6. The width of the inclined sliding groove 57 is greater than the width of the first sliding groove 56. A placement hole is provided. The inner wall of 4 is provided with an arc groove 510, which extends through to the interior of the cylindrical groove 54. The inner wall of the arc groove 510 is slidably disposed with the outer wall of the sliding column 58 and the size is compatible. The second arc groove 513 has the same size as the arc groove 510, so that the rotation angle of the connecting rod 511 and the sliding column 58 is the same. The end of the sliding column 58 away from the arc block 55 is fixed to the surface of the clamping plate 6. The outer wall of the end of the sliding column 58 located in the inclined sliding groove 57 is fixed to the limiting ring plate 59. The limiting ring plate 59 is located in the inclined sliding groove 57 and the size is compatible. The movement of the arc block 55 will drive the sliding column 58 to move.

[0043] When the connecting rod 511 moves downward under the pressure of the test tube, it directly drives the arc block 55 fixed to it to slide downward in the cylindrical groove 54, and the inclined slide groove 57 on the arc block 55 descends accordingly. At this time, the limiting ring plate 59 fixed on the sliding column 58 is located in the inclined slide groove 57. When the inclined slide groove 57 descends, its inclined surface will squeeze the limiting ring plate 59. Since the sliding column 58 is restricted in the horizontal arc groove 510, it cannot follow the inclined slide groove 57 vertically downward. It can only slide horizontally towards the center of the test tube along the arc groove 510 with the clamping plate 6 under the pressure of the inclined surface. The clamping plates 6 in multiple circumferential arrays move centripetally at the same time, and finally hold the test tube evenly and firmly through the rubber pad 61. The precise fit between the limiting ring plate 59 and the inclined slide 57 ensures smooth and reliable power transmission. The angle between the inclined surface of the inclined slide 57 and the vertical direction is preferably designed to be 45 degrees. At this angle, the ratio of the vertical displacement distance of the bearing plate 51 to the horizontal displacement distance of the slide column 58 is 1:1. This simplifies kinematic calculations and can generate sufficient horizontal clamping stroke within a limited vertical stroke.

[0044] The mounting plate 3, bearing plate 51, arc block 55, sliding column 58, and clamping plate 6 are preferably made of polyetheretherketone (PEEK), such as medical-grade VICTRE PEEK 450G. PEEK is a high-performance semi-crystalline thermoplastic with a continuous operating temperature of up to 250°C, far exceeding the maximum temperature required for PCR. The reset spring 53 is preferably made of medical-grade 316L stainless steel, ensuring extremely high dimensional stability of each component under drastic temperature changes and maintaining movement clearance, thereby avoiding movement jamming or clamping force fluctuations caused by thermal expansion and contraction. In addition, PEEK has excellent mechanical strength, wear resistance, and excellent tolerance to common laboratory chemical reagents.

[0045] It should be noted that the calculation formula for the return spring 53 is: F = kx, where F is the external force on the spring, in N, k is the spring constant, in N / m, and x is the deformation of the spring, in m. This formula is used to calculate the elastic force of the alloy spring so that it can be used in this device.

[0046] The implementation principle of a test tube clamping mechanism for a microdroplet PCR instrument according to an embodiment of this application is as follows: In use, the user first opens the hinged sealing cover 2 through the pull ring 21 to expose the placement hole 4 on the mounting plate 3. The PCR test tube is then vertically inserted into the top opening of the placement hole 4. During the insertion of the placement hole 4, the test tube is clamped by the clamping component 5. The clamping component 5 fixes test tubes of various sizes through the moving end clamping plate 6, forming the basic frame for clamping test tubes of the microdroplet PCR instrument. The downward movement distance of the clamping component 5 is linearly related to the movement distance of the clamping plate 6. The thicker the test tube, the deeper the downward pressure, and the greater the inward movement distance of the clamping plate 6, thereby automatically adapting to most diameter test tubes and ensuring uniform clamping force. After the user rotates the clamping component 5 to lock the position of the test tube, the sealing cover 2 is then closed to complete the initial positioning and sealing preparation of all test tubes.

[0047] The above are merely optional embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A test tube clamping mechanism for a droplet PCR instrument, characterized in that: It includes a support housing (1) and a sealing cover (2) hinged to the support housing (1). The support housing (1) is provided with an installation plate (3). The installation plate (3) has a placement hole (4) for placing test tubes. The placement hole (4) is provided with a clamping component (5) for accommodating most test tube sizes. The moving end of the clamping component (5) is provided with a clamping plate (6) for fixing the test tubes.

2. The test tube clamping mechanism for a droplet PCR instrument according to claim 1, characterized in that: The sealing cap (2) has a round hole (22) corresponding to the position of the placement hole (4) for placing the test tube, and a pull ring (21) is fixedly installed on the sealing cap (2).

3. The test tube clamping mechanism for a droplet PCR instrument according to claim 1, characterized in that: A rubber pad (61) for contacting the test tube is fixedly provided on the clamp (6).

4. The test tube clamping mechanism for a droplet PCR instrument according to claim 1, characterized in that: The clamping assembly (5) includes a support plate (51) slidably disposed with the placement hole (4), a rotating plate (52) rotatably disposed on the support plate (51), a return spring (53) fixedly disposed between the rotating plate (52) and the placement hole (4), a connecting rod (511) distributed in a circular array fixedly disposed on the support plate (51), a second sliding groove (512) slidably connected to the connecting rod (511) is opened in the placement hole (4), the connecting rod (511) realizes the translational clamping of the test tube by the clamping plate (6) through the reversing structure, and an arc groove (513) adapted to the size of the connecting rod (511) is opened on the second sliding groove (512).

5. The test tube clamping mechanism for a droplet PCR instrument according to claim 4, characterized in that: The reversing structure includes a cylindrical groove (54) opened in the mounting plate (3), and a circular arc block (55) arranged in a circumferential array is slidably disposed in the cylindrical groove (54). The circular arc block (55) is fixedly connected to the connecting rod (511). A first sliding groove (56) is opened on the side of the circular arc block (55) near the clamping plate (6). An inclined sliding groove (57) is opened in the first sliding groove (56). A circular arc groove (510) extending into the cylindrical groove (54) is opened in the placement hole (4). A sliding column (58) fixedly connected to the clamping plate (6) is slidably disposed in the circular arc groove (510). A limiting ring plate (59) located in the inclined sliding groove (57) is fixedly disposed on the sliding column (58).

6. The test tube clamping mechanism for a droplet PCR instrument according to claim 4, characterized in that: The second groove (512) is vertical.

7. The test tube clamping mechanism for a droplet PCR instrument according to claim 4, characterized in that: The second arc groove (513) is distributed along the long linear array of the second slide groove (512), and the second arc groove (513) has the same size as the first arc groove (510).

8. The test tube clamping mechanism for a droplet PCR instrument according to claim 5, characterized in that: The dimensions of the limiting ring plate (59) are adapted to the dimensions of the inclined slide groove (57).

Images