Switching structure for pipetting device

Abstract

A switching structure for a pipetting device comprises a shell, a plurality of pipetting units arranged in parallel are arranged in the shell, each pipetting unit comprises a piston assembly and an elastic part, and a suction head connecting end of each piston assembly penetrates through the lower end face of the shell and is in limiting fit with the shell to prevent the piston assembly from horizontally moving and downwards separating from the shell. The elastic piece acts on the piston assembly so that the suction head connecting end of the piston assembly can always keep the trend of moving downwards, a limiting base is arranged in the shell, the limiting base is provided with a lower concave face corresponding to the piston assembly, the interior of the limiting base is connected with a limiting plate in a sliding mode, and the limiting plate is provided with an upper concave face corresponding to the piston assembly. A key pulling block which moves synchronously with the limiting plate is arranged on the outer wall surface of the shell; according to the utility model, the structural design is ingenious and reasonable, the clamping mode between the suction head connecting end of the piston assembly and the suction head can be switched by moving the key pulling block and driving the limiting plate, the actual operation is simple, and the use requirements of different users can be met.

Description

Technical Field

[0001] This utility model relates to a switching structure for a pipetting device. Background Technology

[0002] A pipette is an instrument used to accurately transfer a specific volume of solution, and it is widely used in fields such as biology and chemistry. Before each pipetting, the user needs to secure the pipette connector to the tip. Only after the tip is assembled can the liquid be extracted. Currently, the connection between the connector and the tip on pipettes is generally a simple fixed or movable engagement. This simple engagement method cannot adequately meet the needs of users and reduces their operational comfort; therefore, the existing technology needs further improvement and development. Summary of the Invention

[0003] To address the shortcomings mentioned above, this invention provides a switching structure for a pipetting device.

[0004] To achieve the above objectives, this utility model provides a switching structure for a pipetting device, including a housing. The housing contains multiple pipetting units arranged in parallel. Each pipetting unit includes a piston assembly and an elastic element. The tip connection end of the piston assembly penetrates the lower end face of the housing and engages with the housing to prevent horizontal movement and downward disengagement of the piston assembly. The elastic element acts on the piston assembly to ensure that the tip connection end of the piston assembly always maintains a downward movement trend. The housing contains a limiting seat with a concave surface corresponding to the piston assembly and an internally sliding limiting plate. The limiting plate has an upper concave surface corresponding to the piston assembly. A key block that moves synchronously with the limiting plate is provided on the outer wall of the housing. When the key block moves to one side, the concave and upper concave surfaces enclose and fit against the outer wall of the piston assembly, allowing the tip connection end of the piston assembly to move up and down to engage the tip. When the key block moves to the other side, the limiting plate engages with the lower end face of the housing to restrict the up and down movement of the tip connection end of the piston assembly and fix the tip in place.

[0005] Furthermore, the housing is divided into a detachably connected housing one and a housing two. The lower end face of the housing is provided with a U-shaped groove one corresponding to each piston assembly and a limiting part between it and the limiting seat. The limiting part is provided with a U-shaped groove two corresponding to the U-shaped groove one. The piston assembly includes a piston cylinder and a piston rod inserted into the piston cylinder at one end. The piston cylinder is clearance-fitted with the U-shaped groove one and the U-shaped groove two, and a limiting ring is provided on the side wall to restrict the piston cylinder from falling out of the housing. The elastic element is sleeved on the outside of the piston cylinder and its two ends abut against the limiting ring and the limiting part, respectively.

[0006] Furthermore, the other end of the piston rod is engaged with the movable seat, which is slidably connected to one side wall of the housing and driven by the drive shaft to move the piston rod up and down inside the piston cylinder.

[0007] Furthermore, the movable seat has a mounting cavity and a U-shaped groove for each piston rod head.

[0008] Furthermore, the housing is provided with a slide rail along the moving direction of the movable seat, and the movable seat is provided with a protrusion that cooperates with the slide rail.

[0009] Furthermore, the piston cylinder consists of a cylinder body and a connector for mounting the suction head. The connector has an annular groove and a sealing ring is fitted onto the annular groove.

[0010] Furthermore, a partition plate is provided between adjacent piston cylinders, and the two ends of the partition plate are respectively fixed to the lower end face of the housing and the limiting part.

[0011] The advantages of this utility model over the prior art are as follows: The structure of this utility model is ingenious and reasonable. The engagement method between the suction head connection end of the piston assembly and the suction head can be switched by moving the key block and driving the limiting plate. The actual operation is simple and can meet the needs of different users, thus improving the user's operating comfort. Attached Figure Description

[0012] Figure 1 This is an overall plan view of a switching structure for a pipetting device according to the present invention;

[0013] Figure 2 This is a diagram of the internal structure of the shell involved in this scheme (State 1).

[0014] Figure 3 This is a diagram of the internal structure of the shell involved in this scheme (State 2). Detailed Implementation

[0015] like Figure 1 , Figure 2 and Figure 3As shown, an embodiment of this utility model provides a switching structure for a pipetting device, including a housing 1, within which multiple pipetting units 2 are arranged in parallel. The housing 1 is divided into a detachably connected housing one and a housing two, which are connected by a snap-fit ​​mechanism. Each pipetting unit 2 includes a piston assembly 3 and an elastic element 6. The tip connection end of the piston assembly 3 penetrates the lower end face of the housing 1 and engages with the housing 1 to prevent horizontal movement and downward detachment from the housing 1. The elastic element 6 acts on the piston assembly 3 to ensure that the tip connection end of the piston assembly 3 always maintains a downward movement trend. A limiting seat 7 is provided inside the housing 1, with a concave surface 7-1 corresponding to the piston assembly 3 and an internally sliding limiting plate 8. The limiting plate 8 corresponds to... The piston assembly 3 has an upper concave surface 8-1, and the outer wall of the housing 1 has a key block 9. The key block 9 is engaged with the limiting plate 8 and moves synchronously with the limiting plate 8. When the key block 9 moves to one side, the lower concave surface 7-1 and the upper concave surface 8-1 surround and fit against the outer wall of the piston assembly 3, so that the suction head connection end of the piston assembly 3 can move up and down to engage the suction head. When the key block 9 moves to the other side, the limiting plate 8 and the lower end face of the housing 1 cooperate to restrict the up and down movement of the suction head connection end of the piston assembly 3 to fix and engage the suction head. The actual operation is simple. The engagement mode between the suction head connection end of the piston assembly 3 and the suction head can be switched by moving the key block 9 and driving the limiting plate 8. It can meet the needs of different users and improve the user's operating comfort.

[0016] Furthermore, such as Figure 1 , Figure 2 and Figure 3As shown, in this embodiment, the lower end face of the housing is provided with a U-shaped groove 1-1 corresponding to each piston assembly 3, and a limiting part 10 is provided between it and the limiting seat 7. The limiting part 10 is provided with a U-shaped groove 10-1 corresponding to the U-shaped groove 1-1. The piston assembly 3 includes a piston cylinder 4 and a piston rod 5 inserted into the piston cylinder 4 at one end. The piston cylinder 4 is clearance-fitted with the U-shaped groove 1-1 and the U-shaped groove 10-1, and a limiting ring 11 is provided on the side wall to restrict the piston cylinder 4 from falling out of the housing 1. The elastic member 6 is sleeved on the piston cylinder 4 and its two ends abut against the limiting ring 11 and the limiting part 10, respectively. The piston cylinder 4 is composed of a cylinder part 4-1 and a plug part 4-2 for installing the suction head. The plug part 4-2 is provided with an annular groove and a sealing ring 14 is sleeved on the annular groove. In the example, the limiting ring 11 is located at the junction of the cylinder part 4-1 and the plug part 4-2. Under the action of the elastic member 6, the limiting ring 11 of the piston cylinder 4 abuts against the lower end face of the housing, so that the plug part 4-2 passes through the U-shaped groove 1-1 and engages with the suction head. At the same time, for the sake of operational precision, the limiting plate 8 can be set such that when it abuts against one side wall of the limiting seat 7 (state one), the lower concave surface 7-1 and the upper concave surface 8-1 fit perfectly against the outer side wall of the piston cylinder 4. The piston cylinder 4 can move up and down through the lower concave surface 7-1 and the upper concave surface 8-1. When it is necessary to switch the engagement method of the plug part 4-2 and the suction head, it is only necessary to move the key block 9 and drive the limiting plate 8 to move to the other side (state two). The upper concave surface 8-1 abuts against the end of the piston cylinder 4 to restrict the piston cylinder 4 from moving upward.

[0017] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, in this embodiment, the other end of the piston rod 5 is engaged with the movable seat 12. The movable seat 12 is slidably connected to one side wall of the housing and is driven by the drive shaft 13 to drive the piston rod 5 to slide up and down inside the piston cylinder 4. The movable seat 12 is provided with a mounting cavity 12-1 and a U-shaped groove 12-2 for each piston rod 5. The housing 1 is provided with a slide rail 1-2 along the moving direction of the movable seat 12. The movable seat 12 is provided with a protrusion that cooperates with the slide rail 1-2. In use, the movable seat 12 can be driven by the drive shaft 13 to drive all the piston rods 5 to slide up and down inside the piston cylinder 4 to achieve the suction head to draw or discharge liquid.

[0018] Furthermore, such as Figure 1 , Figure 2 and Figure 3 As shown, in this embodiment, a partition plate 15 is provided between adjacent piston cylinders 4. The two ends of the partition plate 15 are fixedly connected to the lower end face of the housing and the limiting part 10, respectively. The partition plate 15 can separate each piston assembly 2.

[0019] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A switching structure for a pipetting device, characterized by: The device includes a housing (1), within which multiple pipetting units (2) are arranged in parallel. Each pipetting unit (2) includes a piston assembly (3) and an elastic element (6). The tip connection end of the piston assembly (3) penetrates the lower end face of the housing (1) and engages with the housing (1) to prevent the piston assembly (3) from moving horizontally and disengaging downward from the housing (1). The elastic element (6) acts on the piston assembly (3) to ensure that the tip connection end of the piston assembly (3) always maintains a downward trend. A limiting seat (7) is provided inside the housing (1), and the limiting seat (7) has a concave surface (7-1) corresponding to the piston assembly (3). The internal sliding connection limiting plate (8) is provided. The limiting plate (8) has an upper concave surface (8-1) corresponding to the piston assembly (3). The outer wall of the housing (1) is provided with a key block (9) that moves synchronously with the limiting plate (8). When the key block (9) moves to one side, the lower concave surface (7-1) and the upper concave surface (8-1) surround and fit the outer wall of the piston assembly (3), so that the suction head connection end of the piston assembly (3) can move up and down to engage the suction head. When the key block (9) moves to the other side, the limiting plate (8) and the lower end face of the housing (1) cooperate to restrict the up and down movement of the suction head connection end of the piston assembly (3) to fix and engage the suction head.

2. A switching structure for a pipetting device according to claim 1, characterized in that: The housing (1) is divided into a detachable housing one and a housing two. The lower end face of the housing is provided with a U-shaped groove (1-1) corresponding to each piston assembly (3) and a limiting part (10) is provided between it and the limiting seat (7). The limiting part (10) is provided with a U-shaped groove (10-1) corresponding to the U-shaped groove (1-1). The piston assembly (3) includes a piston cylinder (4) and a piston rod (5) with one end inserted in the piston cylinder (4). The piston cylinder (4) is clearance-fitted with the U-shaped groove (1-1) and the U-shaped groove (10-1) and the limiting ring (11) is provided on the side wall to restrict the piston cylinder (4) from falling out of the housing (1). The elastic element (6) is sleeved on the piston cylinder (4) and its two ends abut against the limiting ring (11) and the limiting part (10) respectively.

3. A switching structure for a pipetting device according to claim 2, characterized in that: The other end of the piston rod (5) is engaged with the movable seat (12). The movable seat (12) is slidably connected to one side wall of the housing and driven by the drive shaft (13) to drive the piston rod (5) to slide up and down inside the piston cylinder (4).

4. A switching structure for a pipetting device according to claim 3, characterized in that: The movable seat (12) is provided with an installation cavity (12-1) and a U-shaped groove (12-2) for each piston rod (5) at the rod head.

5. A switching structure for a pipetting device according to claim 3 or 4, characterized in that: The housing (1) is provided with a slide rail (1-2) along the moving direction of the movable seat (12), and the movable seat (12) is provided with a protrusion that cooperates with the slide rail (1-2).

6. A switching structure for a pipetting device according to claim 2, characterized in that: The piston cylinder (4) consists of a cylinder part (4-1) and a connector part (4-2) for installing the suction head. The connector part (4-2) is provided with an annular groove and a sealing ring (14) is fitted on the annular groove.

7. A switching structure for a pipetting device according to claim 2, characterized in that: A partition plate (15) is provided between adjacent piston cylinders (4), and the two ends of the partition plate (15) are respectively fixed to the lower end face of the housing and the limiting part (10).

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