A pipette with a reverse retracting tip

Abstract

The application relates to the field of pipettes, and discloses a pipette with a reverse tip ejecting mechanism, which comprises a cylinder, a tip, a moving part and a tip ejecting assembly. The pipette is improved in the structure of the tip ejecting assembly, so that the operation of the tip ejecting mechanism is realized by the moving part moving upwards along a first direction. Compared with the forward tip ejecting mechanism, when the pipette does not need the tip ejecting mechanism and is in a liquid suction state, the piston in the cylinder can be infinitely close to the gun head to reduce the space between the piston and the gun head as much as possible, so that the dead volume of the pipette in the liquid suction state can be effectively controlled, and the liquid suction and discharge effect of the pipette is improved.

Description

Technical Field

[0001] This application relates to the field of pipette technology, and more specifically, to a pipette with a reverse-retard tip. Background Technology

[0002] The content in this section provides only background information related to this application and may not constitute prior art.

[0003] A pipette, also known as a pipette tip, is a measuring tool used to transfer liquid reagents from one container to another within a certain volume range. It is widely used in fields such as biology and chemistry. For pipettes equipped with disposable tips (also known as "TIP tips"), it is usually necessary for the pipette to have an automatic tip ejection function so that the tip can be replaced as needed.

[0004] Currently, pipettes with automatic tip retraction function generally use a forward tip retraction method to remove the tip from the cylinder tip. Such pipettes can be referenced in patent documents with application numbers 2023116860149 and 2023115360634. Specifically, the forward tip retraction method works as follows: when tip retraction is needed, a moving part that drives the piston in the cylinder moves downward along the Z-axis until it contacts the push rod in the tip retraction assembly. The moving part then continues to move downward along the Z-axis to push the push rod downward, thereby causing the tip retraction sleeve fitted on the cylinder to move downward, and finally using the tip retraction sleeve to push the tip out of the pipette tip. Summary of the Invention

[0005] The inventors of this application have discovered that, for pipettes that use a forward-retarding method for retracting the pipette tip, since the moving part is a component used to drive the piston in the cylinder to reciprocate, in order for the moving part to continue to move downward along the Z-axis after contacting the push rod to provide thrust to the push rod, it is necessary to reserve sufficient space between the piston and the pipette tip inside the cylinder for the moving part to drive the piston to move further.

[0006] However, it is foreseeable that when the pipette tip is replaced and the pipette is in the ready-to-aspirate state (i.e., the pipette is about to start aspirating), there is still the reserved space between the piston and the tip mentioned above. The existence of this space will lead to an increase in the dead volume of the pipette (which can be understood as: the volume of the chamber in which the cylinder is connected to the external environment when the pipette is in the ready-to-aspirate state), which may affect the aspiration and dissipation effect of the pipette.

[0007] In view of this, the purpose of this application is to provide a pipette with a reverse-retard tip to effectively control the dead volume when the pipette is in the liquid-ready state.

[0008] The objective of this application is achieved through the following technical solution:

[0009] This application discloses a pipette with a reverse-ejection tip, comprising:

[0010] A cylinder, which contains a piston;

[0011] A suction head is mounted on one end of the cylinder;

[0012] A movable component is located at the end of the cylinder away from the suction head; the movable component is configured to move linearly toward or away from the cylinder in a first direction, so as to drive the piston to move linearly toward or away from the suction head.

[0013] The suction head ejection assembly includes:

[0014] The pusher is configured to move along the first direction between a non-retracted position and a retracted position that pushes the suction head out of the cylinder.

[0015] A force transmission element is drively connected to the pusher; the force transmission element is configured to be triggered by the moving element, which makes a linear motion away from the cylinder along the first direction, to provide a thrust to the pusher that forces the pusher to move from the non-retracted position to the retracted position.

[0016] In some possible embodiments, the force transmission element includes:

[0017] A pivotable force transmission arm, the force transmission arm including a triggering part and a force transmission part: the triggering part and the force transmission part are located on the same side of the force transmission arm and are distributed on both sides of the pivoting center of the force transmission arm; the triggering part is located on the movement path of the moving member and is adapted to be triggered by the moving member;

[0018] A force transmission rod is configured to slide reciprocally along the first direction; one end of the force transmission rod is connected to the pusher.

[0019] A connecting rod, one end of which is hinged to the force transmission part, and the other end of which is hinged to the force transmission rod.

[0020] In some possible embodiments, the suction head assembly further includes an elastic element configured to provide a spring force to the pusher, forcing the pusher to move from the withdrawn position to the non-withdrawn position.

[0021] In some possible embodiments, the pusher includes a pusher sleeve that is fitted onto the outer wall of the cylinder and is movable along the axial direction of the cylinder between the non-retracted position and the retracted position.

[0022] The force transmission component is driven to the jacking sleeve to provide the thrust to the jacking sleeve.

[0023] In some possible embodiments, the jacking member further includes a jacking block connected to the jacking sleeve, and the force transmission member is connected to the jacking sleeve through the jacking block.

[0024] In some possible embodiments, the pipette further includes a drive mechanism configured to drive the moving part to move linearly toward or away from the cylinder along the first direction.

[0025] In some possible embodiments, the drive mechanism includes a lead screw for outputting rotary motion, the lead screw extending along the first direction;

[0026] The moving component cooperates with the lead screw drive to convert the rotational motion output by the lead screw into its own linear motion along the first direction.

[0027] The technical solution of this application embodiment has at least the following advantages and beneficial effects:

[0028] The pipette disclosed in this application improves the structure of the tip ejection assembly, so that the operation of the tip ejection is achieved by a moving part that moves upward in a first direction. Compared with the forward tip ejection method, when the pipette does not need to eject the tip and the pipette is in the liquid-ready state, the piston located in the cylinder can get infinitely close to the pipette tip to minimize the space between the piston and the pipette tip. This can effectively control the dead volume of the pipette when it is in the liquid-ready state, thereby improving the pipette's liquid aspiration and dissipation effect. Attached Figure Description

[0029] Figure 1 A schematic diagram of the pipette structure provided in the embodiments of this application when the moving part does not trigger the force transmission part;

[0030] Figure 2 for Figure 1 Enlarged view of the structure at point A in the middle;

[0031] Figure 3 for Figure 1 Enlarged view of the structure at point B;

[0032] Figure 4 for Figure 1 Enlarged view of the structure at point C;

[0033] Figure 5 A schematic diagram of the pipette structure when the moving part just comes into contact with the force transmission part, provided for an embodiment of this application;

[0034] Figure 6 This is a schematic diagram of the structure of a pipette that triggers the force transmission component after the moving component is provided in an embodiment of this application.

[0035] Icons: 10-Housing, 20-Cylinder, 21-Cylinder body, 22-Nozzle, 23-Piston, 24-Piston rod, 30-Suction head, 40-Moving part, 50-Drive mechanism, 51-Motor, 52-Lead screw, 60-Suction head retraction assembly, 61-Pushing part, 611-Pushing sleeve, 612-Pushing block, 62-Force transmission part, 621-Force transmission arm, 6211-Trigger part, 6212-Force transmission part, 622-Force transmission rod, 623-Connecting rod, 63-Elastic part. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments. The same reference numerals in the accompanying drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0037] Compared to the embodiments shown in the accompanying drawings, feasible embodiments within the scope of this application may have fewer components, other components not shown in the drawings, different components, differently arranged components, or components with different connections, etc. Furthermore, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0038] Please refer to Figures 1 to 6 This application discloses a pipette that at least overcomes the technical problem of large dead volume in known pipettes that use a forward withdrawal method for the pipette tip 30. Generally, the pipette disclosed in this application may include a housing 10, a cylinder 20, a pipette tip 30, a moving part 40, a drive mechanism 50, and a pipette tip withdrawal assembly 60.

[0039] In embodiments of this application, the housing 10 serves as a mounting carrier for related components constituting a pipette. Specifically, one end of the cylinder 20 can be connected to the housing 10, for example, to the bottom of the housing 10, and the other end of the cylinder 20 extends away from the housing 10 along a first direction. It should be noted that the first direction mentioned throughout this application can be understood as... Figure 1 The Z-axis direction shown is the vertical direction. Of course, if the overall position of the pipette changes, the first direction should also change accordingly. For example, when the pipette is placed horizontally, the first direction can be regarded as the horizontal direction.

[0040] The suction tip 30 for aspirating and discharging liquid is mounted at one end of the cylinder 20, specifically at the end of the cylinder 20 opposite to the housing 10. Further, in conjunction with... Figure 2 and Figure 4 As shown, the cylinder 20 may include a cylinder body 21 extending along a first direction and a nozzle 22. One end of the cylinder body 21 is connected to the bottom end of the housing 10, and the nozzle 22 is disposed at the other end of the cylinder body 21. The suction head 30 is adapted to be mounted on the nozzle 22. A piston 23 is also disposed inside the cylinder body 21 of the cylinder 20, and the piston 23 is capable of reciprocating linear motion along the first direction within the piston chamber inside the cylinder body 21.

[0041] Combination Figure 1 , Figure 2 and Figure 4 As shown, the movable component 40 is movably arranged on the housing 10, and the movable component 40 is located at the end of the cylinder 20 away from the pipette tip 30. At the same time, the movable component 40 can move linearly towards or away from the cylinder 20 in a first direction under the drive of the drive mechanism 50. Furthermore, the movable component 40 is connected to the piston 23 through the piston rod 24, so that when the movable component 40 moves under the drive of the drive mechanism 50, the movable component 40 can drive the piston 23 to move linearly towards or away from the pipette tip 30 in the piston chamber of the cylinder 21, thereby realizing the basic aspiration and dissipation functions of the pipette.

[0042] Furthermore, such as Figure 1 As shown, the drive mechanism 50 for driving the moving part 40 may include a motor 51 and a lead screw 52 extending along a first direction. The motor 51 may be fixedly mounted on the top of the housing 10, while the lead screw 52 may be rotatably mounted on the housing 10. One end of the lead screw 52 is connected to the output end of the motor 51 for transmission, so that the motor 51 can drive the lead screw 52 to rotate, thereby outputting rotational motion through the lead screw 52.

[0043] At this time, the movable component 40 and the lead screw 52 drive each other to convert the rotational motion output by the lead screw 52 into linear motion of the movable component 40 itself along the first direction, thereby enabling the movable component 40 to move linearly towards or away from the cylinder 20 along the first direction. Specifically, the movable component 40 can be slidably mounted on the housing 10 so that the movable component 40 can slide back and forth along the first direction. The lead screw 52 passes through the movable component 40 and is threadedly connected to the movable component 40. Thus, when the lead screw 52 rotates under the drive of the motor 51, based on the principle of threaded transmission, the movable component 40 will move linearly along the axial direction of the lead screw 52.

[0044] In the embodiments of this application, the suction head retraction assembly 60 is used to cooperate with the moving member 40 to push the suction head 30 out of the nozzle 22 of the cylinder 20, thereby retracting the suction head 30. Specifically, the suction head retraction assembly 60 may include a pushing member 61 and a force transmission member 62.

[0045] The pusher 61 is configured to move along a first direction between a non-retracted position and a retracted position that ejects the pipette tip 30 from the cylinder 20. In other words, when the pipette tip 30 is normally mounted on the tip 22 of the cylinder 20 and the pipette is performing aspiration and dispensing operations, the pusher 61 is always in the non-retracted position so that the pipette tip 30 can be held on the tip 22; correspondingly, when an operation such as changing the pipette tip 30 is required, the pusher 61 can move along the first direction from the non-retracted position to the retracted position, thereby using the pusher 61 to eject the pipette tip 30 from the tip 22 of the cylinder 20.

[0046] The force transmission member 62 is drively connected to the pusher member 61, so as to selectively provide the pusher member 61 with a thrust that forces the pusher member 61 to move from the non-retracted position to the retracted position. Furthermore, the force transmission member 62 is configured to be triggered by the moving member 40, which moves linearly away from the cylinder 20 in a first direction, to provide the pusher member 61 with a thrust that forces the pusher member 61 to move from the non-retracted position to the retracted position. That is, the force transmission member 62 is arranged on the movement path of the moving member 40, and when the moving member 40 moves linearly away from the cylinder 20 in the first direction (i.e., moves upward in the first direction), the moving member 40 can trigger the force transmission member 62, thereby providing the aforementioned thrust to the pusher member 61 through the force transmission member 62.

[0047] Understandably, regarding this method of providing thrust to the pusher 61, compared to the method used in known pipettes where the moving member 40 moves downward in a first direction to provide thrust to the pusher 61 (i.e., forward withdrawal of the tip 30), when the pipette does not require withdrawal of the tip 30 and is in a ready-to-absorb state, such as... Figure 2 As shown, the movable member 40 can drive the piston 23 located in the cylinder 21 of the cylinder 20 to move downward in the first direction and infinitely close to the pipette tip 22, thereby minimizing the space between the piston 23 and the pipette tip 22 in this state. Furthermore, when the piston 23 and the pipette tip 22 are in contact, the dead volume of the pipette in the liquid-aspirating state can be only the volume of the chamber inside the pipette tip 22. Therefore, by adopting the reverse withdrawal tip 30 method disclosed in this application embodiment, that is, by moving the movable member 40 upward in the first direction to provide thrust to the pushing member 61 through the force transmission member 62, the dead volume of the pipette in the liquid-aspirating state can be effectively controlled, thereby improving the pipette's liquid aspiration and dissipation effect.

[0048] In order to enable the moving member 40, which moves upward in the first direction, to provide thrust to the pushing member 61 through the force transmission member 62, in some embodiments of this application, the force transmission member 62 may further include a force transmission arm 621, a force transmission rod 622, and a connecting rod 623.

[0049] Combination Figure 1 , Figure 3 and Figure 4 As shown, the force transmission arm 621 is hinged to the housing 10 so that the force transmission arm 621 can pivot on the housing 10, and the force transmission arm 621 can be positioned away from the cylinder 20 so that the moving part 40 has sufficient stroke, thereby facilitating the smooth execution of aspiration and dissipation operations by the pipette.

[0050] Furthermore, the force transmission arm 621 may include a triggering part 6211 and a force transmission part 6212. The triggering part 6211 and the force transmission part 6212 are located on the same side of the force transmission arm 621. Specifically, the triggering part 6211 and the force transmission part 6212 are simultaneously located on the side of the force transmission arm 621 closest to the moving member 40 (that is, the bottom side of the force transmission arm 621 shown in the figure). Moreover, the triggering part 6211 and the force transmission part 6212 are distributed on both sides of the pivot center of the force transmission arm 621. At this time, the force transmission arm 621 can be regarded as a pivotable "lever". At the same time, the triggering part 6211 is located on the movement path of the moving member 40 and is suitable to be triggered by the moving member 40. That is to say, the triggering part 6211 is aligned with the moving member 40. When the moving member 40 moves upward along the first direction to the position of the triggering part 6211, the moving member 40 can push the triggering part 6211, thereby causing the force transmission arm 621 to pivot.

[0051] The force transmission rod 622 is configured to slide back and forth in the first direction, specifically, refer to Figure 4 As shown, a sliding groove can be provided on the housing 10 to cooperate with the force transmission rod 622 and extend along the first direction. The force transmission rod 622 is slidably disposed in the sliding groove so that the force transmission rod 622 can reciprocate along the first direction. At the same time, one end of the force transmission rod 622 is connected to the push member 61. One end of the connecting rod 623 is hinged to the force transmission part 6212 of the force transmission arm 621, and the other end of the connecting rod 623 is hinged to the end of the force transmission rod 622 away from the push member 61.

[0052] Thus, referring to Figure 1 As shown, when the pipette tip 30 is not needed, the moving part 40 is located below the force transmission arm 621. At this time, the moving part 40 is not in contact with the trigger part 6211 of the force transmission arm 621, and the pushing part 61 is in the non-retracted position. Correspondingly, when the pipette tip 30 needs to be retracted, the moving part 40 first moves upward along the first direction until the moving part 40 moves to the position shown. Figure 5The position shown is exactly in contact with the trigger part 6211. Subsequently, the moving member 40 continues to move upward in the first direction to trigger (i.e. push) the trigger part 6211. After that, the moving member 40 pushes the trigger part 6211 to force the transmission arm 621 to start pivoting. Thus, by utilizing the cooperation of the transmission part 6212 and the connecting rod 623, the transmission rod 622 moves downward in the first direction. Then, by relying on the transmission rod 622, the pusher 61 is pushed to provide a thrust to the pusher 61, forcing the pusher 61 to move from the non-withdrawn position to the withdrawn position. Thus, the pusher 61 pushes the suction head 30 out of the nozzle 22 of the cylinder 20.

[0053] Understandably, the force transmission component 62, consisting of the force transmission arm 621, the connecting rod 623, and the force transmission rod 622, is based on the lever principle. It can amplify the force when the moving part 40 pushes the trigger part 6211, thereby increasing the thrust provided by the force transmission rod 622 to the pushing part 61. This ensures that the pushing part 61 can reliably push the suction head 30 out of the nozzle 22 of the cylinder 20 under the thrust applied by the force transmission rod 622, and avoid jamming when retracting the suction head 30 as much as possible.

[0054] Meanwhile, to further improve the reliability of the pusher 61 in pushing the suction head 30 out of the nozzle 22 of the cylinder 20 under the aforementioned thrust, the pusher 61 may further include a pusher sleeve 611 and a pusher block 612. Combined with... Figure 2 and Figure 4 As shown, the push sleeve 611 is coaxially sleeved on the outer wall of the cylinder 20, specifically the outer wall of the cylinder body 21. The bottom end of the push sleeve 611 is aligned with the top end of the suction head 30, and the push sleeve 611 can move along the axial direction of the cylinder 20 between the non-retracted position and the retracted position. The push block 612 is connected near the top end of the push sleeve 611. At this time, the force transmission rod 622 of the force transmission component 62 is connected to the push sleeve 611 through the push block 612, that is, the force transmission rod 622 is connected to the push block 612.

[0055] Thus, in conjunction with the above description, when the moving member 40 moves upward in the first direction to push the trigger part 6211 of the force transmission arm 621, the force transmission rod 622 moves downward under the combined action of the force transmission part 6212 of the force transmission arm 621 and the connecting rod 623, thereby pushing the push block 612 downward. This, in turn, drives the push sleeve 611 to move synchronously through the push block 612, and then uses the push sleeve 611 to push the suction head 30 out of the nozzle 22 of the cylinder 20. Using the push sleeve 611, which is sleeved on the outer wall of the cylinder 21, to push the suction head 30 effectively increases the contact area between the push sleeve 611 and the suction head 30, facilitating a smooth and reliable push of the suction head 30 out of the nozzle 22 of the cylinder 20.

[0056] Furthermore, in order to keep the pusher 61 in the non-retracted position when the pipette tip 30 is not needed, or to move the pusher 61 from the retracted position to the non-retracted position after the pipette tip 30 has been retracted once, in some embodiments of this application, the pipette tip retraction assembly 60 may also include an elastic member 63, which provides a spring force to the pusher 61 to force it to move from the retracted position to the non-retracted position. It is understood that this spring force should be less than the thrust provided to the pusher 61 by the force transmission member 62 as described above. Specifically, in conjunction with... Figure 4 As shown, the elastic element 63 can be a straight spring coaxially sleeved on the outer wall of the force transmission rod 622. One end of the straight spring is fixed, for example, one end of the straight spring can be fixed to the housing 10, and the other end of the straight spring is fixedly connected to the outer wall of the force transmission rod 622. Of course, in other embodiments of this application, the elastic element 63 can also have other structural forms.

[0057] Thus, when the pipette tip 30 is not needed, the pusher 61 will always remain in the non-retracted position under the action of the elastic member 63, so that the pipette can smoothly perform operations such as aspiration and dissipation. Correspondingly, during the tip 30 retraction stage, in conjunction with the above description, when the force transmission rod 622 moves downward in the first direction to provide a pushing force to the pusher 61, the downward moving force transmission rod 622 will force the elastic member 63 to undergo further elastic deformation and store a spring force. After the suction head 30 is withdrawn from the nozzle 22 of the cylinder 20, the moving part 40 moves downward in the first direction. When the moving part 40 disengages from the trigger part 6211 of the force transmission arm 621, the force exerted by the moving part 40 on the force transmission arm 621 disappears. At this time, the elastic part 63 can release the pre-stored elastic force to force the force transmission rod 622 to move upward in the first direction. Thus, the force transmission rod 622 drives the pusher 61 to move synchronously, so that the pusher 61 moves from the withdrawn position back to the non-withdrawn position. Furthermore, when the force transmission rod 622 moves upward in the first direction, the force transmission arm 621 will also pivot in the opposite direction and reset under the combined action of the force transmission rod 622 and the connecting rod 623, thus preparing for the next withdrawal of the suction head 30.

[0058] The above are merely preferred 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 pipette with a reverse-ejection tip, characterized in that, include: A cylinder, which contains a piston; A suction head is mounted on one end of the cylinder; A movable component is located at the end of the cylinder away from the suction head; the movable component is configured to move linearly toward or away from the cylinder in a first direction, so as to drive the piston to move linearly toward or away from the suction head. The suction head ejection assembly includes: The pusher is configured to move along the first direction between a non-retracted position and a retracted position that pushes the suction head out of the cylinder. An elastic element configured to provide a spring force to the pusher, forcing the pusher to move from the withdrawn position to the non-withdrawn position; A force transmission element is drively connected to the pusher; the force transmission element is configured to be triggered by the moving element, which makes a linear motion away from the cylinder along the first direction, to provide a thrust to the pusher that forces the pusher to move from the non-retracted position to the retracted position; The force transmission component includes: A pivotable force transmission arm, the force transmission arm including a triggering part and a force transmission part: the triggering part and the force transmission part are located on the same side of the force transmission arm and are distributed on both sides of the pivoting center of the force transmission arm; the triggering part is located on the movement path of the moving member and is adapted to be triggered by the moving member; A force transmission rod is configured to slide reciprocally along the first direction; one end of the force transmission rod is connected to the pusher. A connecting rod, one end of which is hinged to the force transmission part, and the other end of which is hinged to the force transmission rod.

2. The pipette with a reverse-retarded tip according to claim 1, characterized in that, The pusher includes a pusher sleeve, which is sleeved on the outer wall of the cylinder and can move along the axial direction of the cylinder between the non-retracted position and the retracted position. The force transmission component is driven to the jacking sleeve to provide the thrust to the jacking sleeve.

3. The pipette with a reverse-retarded tip according to claim 2, characterized in that, The jacking component further includes a jacking block, which is connected to the jacking sleeve, and the force transmission component is connected to the jacking sleeve through the jacking block.

4. The pipette with a reverse-retarded tip according to claim 1, characterized in that, It also includes a drive mechanism configured to drive the moving member to make linear movements along the first direction toward or away from the cylinder.

5. The pipette with a reverse-ejection tip according to claim 4, characterized in that, The drive mechanism includes a lead screw for outputting rotary motion, the lead screw extending along the first direction; The moving component cooperates with the lead screw drive to convert the rotational motion output by the lead screw into its own linear motion along the first direction.

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