High-stability pipette

Abstract

The utility model relates to the technical field of experimental instruments, in particular to a high-stability pipette which comprises a shell, a suction head withdrawing sleeve, a stepping motor and a driving mechanism, and the driving mechanism comprises a lead screw, a sliding block, a lead screw sliding seat, a guide rail, a piston rod, a cavity, a circuit board and an air pressure sensor. According to the high-stability pipette, lifting of the piston rod is achieved through guiding of the lead screw sliding seat of the double sliding blocks, so that liquid suction and liquid spitting of the piston rod are achieved, the internal structure is simplified, the movement range of the piston rod is greatly widened, the stability of the piston rod during movement is guaranteed, and meanwhile the pressure in the cavity is accurately sensed through the air pressure sensor; and the working safety of the pipette is further ensured.

Description

Technical Field

[0001] This utility model relates to the field of experimental instrument technology, and in particular to a highly stable pipette. Background Technology

[0002] Sampling and pipetting instruments are widely used in biological experiments such as biochemistry, molecular biology, and cell biology. Their function is to sample and transfer a certain volume of liquid. The pipetting device is one of its core components, used for actions such as drawing, transporting, and transferring liquids in standard containers. Common containers include standard SBS plates, such as 8-well, 96-well, and 384-well deep-well plates, reagent plates, and standard 1-20ml vacuum blood sample tubes.

[0003] Existing pipettes are generally large in size. They use a servo motor to drive the piston rod through a ball screw and screw nut to achieve lifting and lowering. Because the screw nut and piston rod need to be guided by a guide mechanism when lifting and lowering, their internal structure is complex and inconvenient to assemble. In addition, if the piston rod stroke is large, the stability of the guide mechanism cannot be guaranteed. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a highly stable pipette that is simple in structure, easy to assemble, stable in operation, and safe and reliable.

[0005] This utility model is achieved through the following technical solution:

[0006] A high-stability pipette includes a housing, a suction tip sleeve disposed at both ends of the housing, a stepper motor, and a drive mechanism disposed within the housing and connected to the stepper motor. The drive mechanism includes a lead screw, sliders, a lead screw slide block, a guide rail, a piston rod, a cavity, a circuit board, and a pressure sensor. The guide rail is fixed inside the housing and is perpendicular to the horizontal plane. The lead screw is connected to the output shaft of the stepper motor and is parallel to the guide rail. The sliders are a set and slidably connected to the guide rail. The rear side of the lead screw slide block is fixed to the two sliders, and one end of the lead screw slide block is threadedly connected to the lead screw. The cavity is fixed at the bottom end inside the housing. The bottom end of the piston rod passes through the cavity and is inserted into the suction tip sleeve. The top end of the piston rod is fixed to the lead screw slide block. The circuit board is fixed inside the housing. The pressure sensor is fixed on the circuit board and correspondingly disposed on one side of the cavity. The pressure sensor is connected to the inner cavity of the cavity.

[0007] To further ensure the stability of the lead screw slide during movement, preferably, the lead screw slide has an inverted T-shaped structure, with a guide portion in the middle for mounting two sliders. One end of the guide portion is fixed with a lead screw nut connected to the lead screw, and the other end of the guide portion has a connecting portion for inserting and fixing the top of the piston rod.

[0008] In order to accurately sense whether the lead screw slide has been raised or lowered to the correct position, a first sensing plate is fixed on the lead screw slide, and a first sensor that can sense the first sensing plate is fixed on the circuit board.

[0009] In order to accurately sense whether the suction head sleeve is in contact with the test tube, a movable seat is fixed at the top of the suction head sleeve. The movable seat is set inside the housing, and a second sensing plate is fixed at one end of the movable seat. A second sensor that can sense the second sensing plate is fixed on the circuit board.

[0010] In order to enable the suction head sleeve to automatically reset, a set of elastic rods is fixed on the movable seat. The elastic rods pass through the cavity and are elastically connected to the cavity by springs.

[0011] The beneficial effects of this utility model are: the high-stability pipette is guided by a lead screw slide with a double slider to realize the lifting and lowering of the piston rod, thereby realizing the piston rod to aspirate and expel liquid, simplifying the internal structure, greatly improving the range of motion of the piston rod, and ensuring the stability of the piston rod during movement. At the same time, the pressure sensor accurately senses the pressure inside the cavity, further ensuring the safety of the pipette during operation. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the high-stability pipette of this utility model;

[0013] Figure 2 This is a schematic diagram of the internal structure of the high-stability pipette of this utility model. Detailed Implementation

[0014] The preferred embodiments of this utility model will now be described in detail with reference to the accompanying drawings, so that the advantages and features of this utility model can be more easily understood by those skilled in the art, thereby providing a clearer and more definite definition of the scope of protection of this utility model. Directional terms mentioned in this utility model, such as "up" and "down,"

[0015] Terms such as "front," "back," "left," "right," "top," and "bottom" are merely directional references to the accompanying drawings. Therefore, the directional terms used are for the purpose of explaining and understanding this utility model, and not for limiting this utility model.

[0016] like Figure 1 The high-stability pipette shown includes a housing 1, a suction tip sleeve 3 disposed at the bottom of the housing 1, a stepper motor 2 disposed at the top of the housing 1, and a drive mechanism disposed inside the housing 1 and connected to the stepper motor 2.

[0017] Specifically, in combination Figure 2As shown, the driving mechanism includes a lead screw 7, a slider 6, a lead screw slide 5, a guide rail 4, a piston rod 9, a cavity 10, a circuit board 16, and a pressure sensor 17. The guide rail 4 is fixed inside the housing 1 and is perpendicular to the horizontal plane. The lead screw 7 is connected to the output shaft of the stepper motor 2 and is parallel to the guide rail 4. The sliders 6 are a set and are slidably connected to the guide rail 4. The lead screw slide 5 has an inverted T-shaped structure with a guide part in the middle for mounting two sliders 6. The sliders 6 are detachably connected to the lead screw slide 5 by screws. One end (right end) of the guide part is fixed with a lead screw nut 8 connected to the lead screw 7. The lead screw nut 8 is threadedly connected to the lead screw 7. The other end (left end) of the guide part has a connecting part for inserting and fixing the top end of the piston rod 9. The cavity 10 is fixed to the bottom end inside the housing 1. The bottom end of the piston rod 9 passes through the cavity 10 and is inserted into the suction port. Inside the head sleeve 3, the top end of the piston rod 9 is detachably connected to the lead screw slide 5. The circuit board 16 is fixed inside the housing 1. The air pressure sensor 17 is fixed on the circuit board 16 and is correspondingly arranged on one side (right side) of the cavity 10. The air pressure sensor 17 is connected to the inner cavity of the cavity 10. A first sensing plate 11 is fixed on the lead screw slide 5. A first sensor 12 that can sense the first sensing plate 11 is fixed on the circuit board 16. A movable seat 13 is fixed at the top end of the suction head sleeve 3. The movable seat 13 is arranged inside the housing 1. A set of elastic rods 18 is fixed on the movable seat 13. The elastic rods 18 penetrate the cavity 10 and are elastically connected to the cavity 10 by a spring. A second sensing plate 14 is fixed at one end (right end) of the movable seat 13. A second sensor 15 that can sense the second sensing plate 14 is fixed on the circuit board 16.

[0018] In use, the high-stability pipette descends to a fixed position, the retraction tip sleeve 3 aligns with the test tube, and the retraction tip sleeve 3 moves upward under pressure, causing the moving seat 13 to move upward. At this time, the second sensor 15 senses the second sensing plate 14. The stepper motor 2 drives the lead screw 7 to rotate, and the lead screw nut 8 descends along the lead screw 7, causing the lead screw slide 5 to descend along the guide rail, thereby driving the piston rod 9 to move up and down along the cavity 10. The first sensor 12 senses the first sensing plate 11, causing negative or positive pressure to be generated inside the retraction tip sleeve 3, realizing the aspiration or dispensing of reagents or samples.

[0019] Furthermore, in the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "set up," "equipped with," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0020] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A high-stability pipette, comprising a housing, a suction tip sleeve respectively disposed at both ends of the housing, a stepper motor, and a drive mechanism disposed within the housing and connected to the stepper motor, characterized in that: The driving mechanism includes a lead screw, a slider, a lead screw slide block, a guide rail, a piston rod, a cavity, a circuit board, and a pressure sensor. The guide rail is fixed inside the housing and is perpendicular to the horizontal plane. The lead screw is connected to the output shaft of the stepper motor and is parallel to the guide rail. The sliders are a set and are slidably connected to the guide rail. The rear side of the lead screw slide block is fixed to the two sliders, and one end of the lead screw slide block is threaded to the lead screw. The cavity is fixed at the bottom inside the housing. The bottom end of the piston rod passes through the cavity and is inserted into the suction head sleeve. The top end of the piston rod is fixed to the lead screw slide block. The circuit board is fixed inside the housing. The pressure sensor is fixed on the circuit board and is correspondingly arranged on one side of the cavity. The pressure sensor is connected to the inner cavity of the cavity.

2. The high-stability pipette according to claim 1, characterized in that: The lead screw slide has an inverted T-shaped structure, with a guide part in the middle for mounting two sliders. One end of the guide part is fixed with a lead screw nut connected to the lead screw, and the other end of the guide part has a connecting part for inserting and fixing the top of the piston rod.

3. The high-stability pipette according to claim 2, characterized in that: A first sensing plate is fixed on the lead screw slide, and a first sensor capable of sensing the first sensing plate is fixed on the circuit board.

4. The high-stability pipette according to claim 1, characterized in that: The top of the suction head sleeve is fixed with a movable base, which is disposed inside the housing. A second sensing plate is fixed at one end of the movable base, and a second sensor capable of sensing the second sensing plate is fixed on the circuit board.

5. The high-stability pipette according to claim 4, characterized in that: A set of elastic rods is fixed on the movable seat. The elastic rods pass through the cavity and are elastically connected to the cavity by springs.

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