CN111097559A

CN111097559A - Stripping mechanism and liquid transfer device

Info

Publication number: CN111097559A
Application number: CN201811270702.6A
Authority: CN
Inventors: 高建东; 李景; 吴文昊; 邹良英
Original assignee: MGI Tech Co Ltd
Current assignee: MGI Tech Co Ltd
Priority date: 2018-10-29
Filing date: 2018-10-29
Publication date: 2020-05-05
Anticipated expiration: 2038-10-29
Also published as: CN111097559B

Abstract

The stripping mechanism is used for withdrawing a pipette tip from an adapter and comprises a stripping plate, the stripping plate comprises a plurality of stripping portions, the stripping portions are provided with a plurality of stripping through holes penetrating through the stripping plate, the stripping through holes are used for sleeving the adapter, stripping distances between the stripping portions and the end portion of the pipette tip are at least partially different, and when the stripping plate is close to the pipette tip to move, the adapter moves in the stripping through holes, so that the stripping portions successively abut against the end portion of the pipette tip to withdraw the pipette tip from the adapter, and resistance of the stripping plate can be reduced. In addition, in the material removing process, the end part of the material removing through hole is successively abutted against the pipette head, so that the resistance of the material removing plate cannot be suddenly changed, and the vibration of the pipetting device in the material removing process can be reduced.

Description

Stripping mechanism and liquid transfer device

Technical Field

The invention belongs to the field of gene sequencing equipment, and particularly relates to a stripping mechanism and a liquid transfer device.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

With the widespread application of the gene sequencing industry, the gene sequencing technology becomes a work of clinical experiments. In the automated sample preparation aiming at the second generation sequencing technology, a liquid transfer device is required to move and distribute liquid so as to complete operations such as sample adding, reagent distribution, ultra-micro liquid transfer and the like. After the existing pipetting device finishes pipetting, a blanking plate of a material removing mechanism moves towards a pipette tip to enable the end part of a material removing hole in the blanking plate to be pushed against the pipette tip, and the pipette tip is withdrawn from an adapter simultaneously.

Because the liquid-transfering device generally has more adapter and pipettor rifle head, lead to taking off the flitch and need use great thrust just can withdraw from the pipettor rifle head when withdrawing from the pipettor rifle head. Moreover, after the pipette tip is withdrawn, the resistance of the stripper plate disappears suddenly, and the stripper plate can generate large vibration in the stripping process, so that other precise elements in the pipetting device can be damaged.

Disclosure of Invention

In view of the above, there is a need for a material stripping mechanism and a pipetting device that can reduce the resistance to withdrawal of a pipette tip.

A stripping mechanism for withdrawing a pipette tip from an adapter comprises a stripping plate, wherein the stripping plate comprises a plurality of stripping parts, the stripping parts are provided with a plurality of stripping through holes penetrating through the stripping plate, the stripping through holes are used for sleeving the adapter,

the material removing part is at least partially different from the material removing distance between the end parts of the pipette tips, and when the material removing plate moves close to the pipette tips, the adapter moves in the material removing through hole, so that the material removing part sequentially props against the end parts of the pipette tips to withdraw the pipette tips from the adapter.

Preferably, the plurality of stripping parts are at least partially arranged on the side surface of the stripping plate in a step shape.

Preferably, the material removing distance of the material removing part increases progressively from the middle part to the two ends, so that when the material removing plate moves close to the pipette tip, the material removing part sequentially collides with the end part of the pipette tip from the middle part to the two ends so as to withdraw the pipette tip from the adapter.

Preferably, the device further comprises a material removing driving device, wherein the material removing driving device is connected with the material removing plate and used for driving the material removing plate to be close to or far away from the pipette head.

A liquid-transfering device comprises a liquid-transfering mechanism and the material-removing mechanism, wherein the liquid-transfering mechanism comprises an adapter, a plunger pump and a plunger pump driving device,

the plunger pump comprises a plurality of sealed cavities and a plunger movably arranged in the sealed cavities, and the sealed cavities are connected with the adapter; one end of the plunger is positioned in the sealed cavity, and the other end of the plunger is connected with the plunger pump driving device;

the end part of the adapter penetrates through a stripping through hole of a stripping plate of the stripping mechanism, and when the pipetting mechanism moves to enable the adapter to be connected with a pipette tip, the plunger pump driving device drives the plunger to move along the length direction of the sealed cavity so as to suck liquid into the sealed cavity through the pipette tip and the adapter or discharge the liquid in the sealed cavity through the adapter and the pipette tip; when the stripper plate moves close to the pipette tip, the plurality of stripper portions sequentially abut against the pipette tip so as to withdraw the pipette tip from the adapter.

Preferably, the apparatus further comprises an ejector, the ejector comprising:

the outer sleeve is internally provided with an ejection containing cavity extending along the length direction of the outer sleeve;

the packaging screw is arranged at one end of the outer sleeve and is positioned at the opening of the ejection containing cavity;

the elastic piece is positioned in the ejection accommodating cavity and abutted against the packaging screw, and the packaging screw packages the elastic piece in the ejection accommodating cavity;

one end of the ejector pin extends out of the end part, opposite to the packaging screw, of the outer sleeve, the other end of the ejector pin props against the elastic piece, and when the liquid transfer mechanism moves to the position close to the pipette tip and the adapter is connected with the pipette tip, the ejector pin props against the box body of the pipette tip so that the elastic piece is compressed; when the liquid transfer mechanism carries the pipette tip to move reversely, the elastic piece pushes the box body of the pipette tip so that the pipette tip is separated from the box body of the pipette tip.

Preferably, the linear driving mechanism further comprises:

the linear driving rack comprises a top plate, a bottom plate and a connecting column, the top plate and the bottom plate are respectively connected to two end parts of the connecting column to form a C-shaped structure, and the liquid transfer mechanism is movably connected to the connecting column;

the linear driving slide block is connected with the liquid transfer mechanism;

and the linear driving motor is connected with the linear driving sliding block and used for driving the linear driving sliding block to move so as to drive the liquid transfer mechanism to move along the connecting column, so that the adapter of the liquid transfer mechanism is close to the pipette tips to move until the adapter is connected with the pipette tips.

Preferably, the stripper mechanism further comprises a limit switch for detecting the moving distance of the stripper plate.

Preferably, the adapter comprises a cylindrical barrel, the cylindrical barrel comprises a positioning sealing part, a mounting part and a gun head adapting part,

the rotating surface of the positioning sealing part is provided with threads, and the end part of the threads close to the mounting part is provided with a sealing ring;

the circumferential surface of the mounting part is provided with two mutually symmetrical mounting planes for mounting or dismounting the adapter;

the pipette head adapting part sequentially comprises a radial positioning part, a connecting conical surface, a bulge and a plug along the direction far away from the mounting part, an adapting part positioning step is arranged between the radial positioning part and the mounting part and is used for axially positioning the pipette head, and the outer diameter of the radial positioning part is matched with the inner diameter of an insertion opening of the pipette head and is used for radially positioning the pipette head; one end of the connecting conical surface is connected with the radial positioning part, and the other end of the connecting conical surface is connected with the bulge; the protrusion is annular and comprises a first conical surface and a second conical surface, the first conical surface is connected with the connecting conical surface and the second conical surface respectively, and the second conical surface is connected with the plug.

Preferably, the plunger pump driving device comprises a plunger driving frame, a plunger driving guide column, a plunger driving sliding block, a connecting block, a guide rail fixing block and a plunger driver;

a containing cavity is arranged in the plunger driving frame, and a liquid transfer guide rail extending along the length direction of the containing cavity is arranged on the inner wall of the containing cavity;

the plunger driving guide column is accommodated in the accommodating cavity and extends along the length direction of the accommodating cavity, one end of the plunger driving guide column is connected with the end part of the accommodating cavity, and the other end of the plunger driving guide column is connected with the guide rail fixing block;

the plunger driving slide block is movably connected with the guide rail and comprises a plurality of pipetting guide holes, and the plunger driving guide column penetrates through the pipetting guide holes;

the connecting block is connected with the plunger driving slide block and the plunger;

the plunger driver is connected with the plunger driving sliding block and used for driving the plunger driving sliding block to move along the pipetting guide rail under the guidance of the plunger driving guide column, so that the connecting block drives the plunger to move along the length direction of the sealing cavity.

Compared with the prior art, the material removing mechanism and the liquid transferring device are different at least in part through the distance between the material removing part provided with the material removing plate and the end part of the pipette head, so that the material removing part can successively push the pipette head when the material removing plate withdraws from the pipette head, and the resistance of the material removing plate can be reduced. In addition, in the material removing process, the material removing part sequentially pushes the pipette head, so that the resistance of the material removing plate cannot change suddenly, and the vibration of the pipetting device in the material removing process can be reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view of the structure of the pipetting device.

FIG. 2 is a schematic view of the structure of the pipetting device in a disassembled state.

Fig. 3 is a schematic structural diagram of the stripping mechanism.

Fig. 4 is a structural schematic diagram of a stripper plate of the stripper mechanism.

Fig. 5 is a schematic view of a partial cross-sectional structure at V-V in fig. 1.

Fig. 6 is a schematic structural diagram of the stripper mechanism when pushing against the pipette tip.

Fig. 7 is a schematic structural view of the pipetting mechanism.

Fig. 8 is a schematic sectional view taken along line VIII-VIII in fig. 7.

Fig. 9 is a schematic structural view of the adapter.

Fig. 10 is a schematic cross-sectional view taken at X-X in fig. 9.

Fig. 11 is a schematic structural view of the ejector.

Fig. 12 is a schematic sectional view at XII-XII in fig. 11.

Fig. 13 is a schematic structural view of the linear drive mechanism.

Fig. 14 is a schematic view of the structure in the direction C of fig. 13.

Description of the main elements

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

So that the manner in which the above recited objects, features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. In addition, the embodiments and features of the embodiments of the present application may be combined with each other without conflict. In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention, and the described embodiments are merely a subset of the embodiments of the present invention, rather than a complete embodiment. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In various embodiments of the present invention, for convenience in description and not in limitation, the term "coupled" as used in the specification and claims of the present application is not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.

Fig. 1 is a schematic configuration diagram of the liquid transfer device, and fig. 2 is a schematic configuration diagram of the liquid transfer device in a disassembled state. As shown in fig. 1 and 2, the pipetting device includes a pipetting mechanism 20, a stripping mechanism 10, and a linear driving mechanism 30. The pipetting mechanism 20 is used to achieve precise quantitative transfer of liquid, and can aspirate liquid or discharge liquid through the pipette tip 50. The stripping mechanism 10 is used for withdrawing the loaded pipette tip 50, and the linear driving mechanism 30 is connected with the pipetting mechanism 20 and used for moving the pipetting mechanism 20 in a linear direction.

The depilling mechanism 10 is used to withdraw the pipette tip 50 from the adapter 21. Fig. 3 is a schematic structural diagram of the stripping mechanism 10. As shown in fig. 3, the stripping mechanism 10 includes a stripping plate 11 and a stripping driving device 12.

The stripper driving device 12 is connected to the stripper plate 11 and configured to move the stripper plate 11 to approach or be away from the pipette tip 50. The stripping driving device 12 comprises a stripping slide block 121, a stripping guide rail 122, a stripping lead screw 123 and a stripping motor 124. In this embodiment, the material-removing guide rail 122 is disposed on the outer wall of the liquid-moving mechanism 20, the material-removing slider 121 is movably connected to the material-removing guide rail 122, and the end portion of the material-removing slider 121 is connected to the material-removing plate 11, and the material-removing slider 121 can drive the material-removing plate 11 to move back and forth along the material-removing guide rail 122. The output shaft of the stripping motor 124 is connected to a stripping screw 123, which can drive the stripping screw to rotate. The stripping screw 123 passes through a nut (not shown) on the stripping slide 121, so that the rotation of the stripping motor 124 can be converted into the movement of the stripping slide 121. When the stripping motor 124 rotates, the stripping slider 121 can be driven to drive the stripping plate 11 to move. In other embodiments, the stripping motor 124 may be a linear motor, and the output shaft is connected to the stripping slide 121 to drive the stripping slide 121 to move. In addition, the stripping mechanism 10 further includes a stripping limit switch 13 for detecting the moving distance of the stripping plate 11.

Fig. 4 is a schematic structural view of the stripper plate 11 of the stripper mechanism 10. As shown in fig. 4, the stripper plate 11 includes a plurality of mounting holes 112 and a plurality of stripper portions 114. Mounting holes 112 are used to attach ejector 40 (shown in fig. 2 and 3). The stripper 114 is elongated and is disposed on a side surface of the stripper plate 11. In this embodiment, the material removing part 114 is provided with one or more material removing through holes 111 penetrating through the material removing plate 11, and the inner diameter of the material removing through hole 111 is adapted to the outer diameter of the adapter 21, so that the adapter 21 can pass through the material removing through hole 111 to be connected with the pipette tip 50. The outer diameter of the joint of the adapter 21 and the pipette tip 50 is correspondingly matched with the material removal through hole 111, so that after the adapter 21 is inserted into the pipette tip 50, the outer diameter of the pipette tip 50 is larger than the inner diameter of the material removal through hole 111. Therefore, when the stripper plate 11 moves downward, the stripper portion 114 collides with the pipette tip 50 to strip the pipette tip 50.

In the present embodiment, the stripper 114 is elongated and is located on the side surface of the stripper plate 11. Each stripper portion 114 has one or more stripper through holes 111. The stripping through holes 111 on the same stripping part 114 are a stripping group 113. The number of the stripping through holes 111 of each stripping set 113 can be equal or different. Thus, the distances between the stripper portions 114 within the same stripper group 113 and the end of the pipette tip 50 (i.e. the stripper distances of the stripper portions 114) are the same.

Fig. 5 is a schematic view of a partial cross-sectional structure at V-V in fig. 1. As shown in fig. 5, distances D between the material removing portions 114 of different material removing groups 113 and the end portions of the pipette tips 50 (i.e., material removing distances of the material removing through holes 111) are different, so that when the material removing plate 11 moves in a direction (a direction B-B shown in fig. 5) close to the pipette tips 50, the adapter 21 moves in the material removing through holes 111, the material removing portions 114 sequentially collide with the pipette tips 50 to sequentially withdraw the pipette tips 50 from the adapter 21, that is, when the material removing plate 11 approaches the pipette tips 50, the material removing portion 114 closer to the pipette tips 50 may firstly collide with the pipette tips 50 to withdraw the pipette tips 50 from the adapter 21, and then the material removing portion 114 slightly farther from the pipette tips 50 may secondly collide with the pipette tips 50. In this way, in the process that the stripper plate 11 approaches the pipette tip 50 to withdraw from the pipette tip 50, the stripper portion 114 can continuously abut against the pipette tip 50, so that the stripper plate 11 can continuously receive the withdrawal resistance of the pipette tips 50, and cannot simultaneously receive the withdrawal resistance of all the pipette tips 50, thereby reducing the maximum resistance of the stripper plate 11 when withdrawing from the pipette tip 50. Moreover, in the process of withdrawing the pipette tip 50, the material removing part 114 successively pushes against the pipette tip 50, so that the resistance of the material removing plate 11 does not change suddenly, and the vibration of the pipetting device in the material removing process can be reduced.

In this embodiment, the material removing through holes 111 are multiple in number, the material removing portions 114 are arranged on the side surfaces of the material removing plate 11 in a strip shape, so that the material removing through holes 111 are distributed in the material removing plate 11 in a matrix shape, and each row of the material removing through holes 111 (i.e. the material removing through holes 111 located in the same material removing portion 114) is a group of material removing groups 113. Fig. 6 is a schematic structural view of the stripper plate 11 when pushing against the pipette tip 50. As shown in fig. 6, the stripping distance of the stripping portion 114 located in the middle of the stripping plate 11 is the shortest, and the stripping distance of the stripping portion 114 of the stripping group 113 increases from the middle to both ends, that is, the stripping distance of the stripping portion 114 located at both ends of the stripping plate 11 is the largest, so that the stripping portion 114 forms a multi-step structure. In the process that the stripper plate 11 withdraws from the pipette tips 50, the pipette tips 50 in the middle part are withdrawn first, and then the pipette tips 50 are withdrawn sequentially from the middle part to the two ends. In other embodiments, the stripping portion 114 of each stripping set 113 may also be circular, and the stripping through holes 111 are arranged in a circle to form a concentric arrangement. In addition, the stripper portion 114 may be arranged in other ways.

The skilled person can set the number of the stripper through holes 111 of each stripper group 113 appropriately according to the withdrawal resistance of a single pipette tip 50, so that the maximum resistance of the stripper plate 11 in withdrawing the pipette tip 50 can be adjusted. In addition, the frequency of the ejection resistance of the pipette tips 50 on the stripper plate 11 can be controlled by reasonably setting the stripping distance of each stripping part 114, so that the vibration of the stripper plate 11 on the pipetting device during operation is reduced.

Fig. 7 is a schematic structural view of the pipetting mechanism 20, and fig. 8 is a schematic structural view of a section from VIII to VIII in fig. 7. As shown in fig. 7 and 8, the pipetting mechanism 20 includes an adapter 21, a plunger pump 23, and a plunger pump driving device 22. The plunger pump 23 is connected with the adapter 21, and the plunger pump driving device 22 is connected with the plunger pump 23 and used for driving the plunger pump 23 to suck or discharge liquid through the pipette tip 50 through the adapter 21.

The plunger pump 23 includes a plurality of seal cavities 231 and a plunger 232. The plunger 232 is movably embedded in the seal cavity 231 and can move in the seal cavity 231. The seal cavity 231 is connected with the adapter 21, one end of the plunger 232 is located in the seal cavity 231, and the other end is connected with the plunger pump driving device 22. When the plunger 232 moves close to the adapter 21, the sealed space in the sealed cavity 231 becomes smaller, the internal pressure increases, and the liquid in the sealed cavity 231 can be discharged; when the plunger 232 is moved away from the adapter 21, the sealed space within the seal cavity 231 is increased and the internal pressure is reduced to draw liquid into the seal cavity 231 from the adapter 21.

The plunger pump driving device 22 is used for driving the plunger 232 to move in the sealed cavity 231 and comprises a plunger driving frame 227, a plunger driving guide column 222, a plunger driving sliding block 221, a connecting block 226, a guide rail fixing block 225 and a plunger driver 223.

A cavity 2271 is disposed in the plunger driving rack 227, and a guide rail (not shown in the drawings) extending along the length direction of the cavity 2271 is disposed on the inner wall of the cavity 2271. The plunger driving guide column 222 is accommodated in the accommodating cavity 2271 and extends along the length direction of the accommodating cavity 2271, one end of the plunger driving guide column is connected with the end part of the accommodating cavity 2271, and the other end of the plunger driving guide column is connected with the guide rail fixing block 225. The plunger driving slider 221 is movably connected to the guide rail, and can move back and forth along the length direction of the guide rail. The plunger drive slide 221 includes a plurality of guide holes between the rail fixing block 225 and the end of the receiving cavity 2271 such that the plunger drive guide 222 passes through the guide holes of the plunger drive slide 221. The connecting block 226 is connected to the plunger driving slider 221, and the plunger driving slider 221 and the guide rail fixing block 225 are respectively located at two sides of the guide rail fixing block, and the end of the plunger 232 is connected to the connecting block 226. The plunger driver 223 is connected to the plunger driving slider 221, and is configured to drive the plunger driving slider 221 to move along the guide rail between the guide rail fixing block 225 and the end of the accommodating cavity 2271 under the guidance of the plunger driving guide column 222, so that the connecting block 226 drives the plunger 232 to move along the length direction of the seal cavity 231. In this embodiment, the plunger driver 223 is a motor, an output shaft of the motor is connected to a plunger driving screw 224, the plunger driving slider 221 is provided with a nut (not shown in the figure), and the plunger driving screw 224 extends along the length direction of the guide rail and passes through the nut of the plunger driving slider 221, so that the rotation of the motor can be converted into the linear movement of the plunger driving slider 221. In the present embodiment, an electro-optical limit switch is attached to the stroke of the plunger pump driving device 22 to detect and limit the moving distance of the plunger driving slider 221.

When the plunger driver 223 rotates, the plunger driver screw 224 can be driven to rotate to move the plunger driving slide 221 along the pipetting guide under the guidance of the plunger driving guide column 222, so that the connection block 226 drives the plunger 232 to move along the length direction of the sealed cavity 231. In other embodiments, the plunger driver 223 can be a linear motor, and the output shaft is connected to the plunger driving slide 221 to directly push the plunger driving slide 221 to move along the pipetting rail.

Fig. 9 is a schematic structural view of the adapter 21, and fig. 10 is a schematic structural view of a cross section at X-X in fig. 9. As shown in fig. 9 and 10, the adapter 21 includes a cylindrical barrel, and the cylindrical barrel includes, from top to bottom, a positioning sealing portion 211, a mounting portion 212, and a lance tip adapter portion 213.

The rotation surface of the positioning sealing portion 211 is provided with a thread (not shown in the figure), and an end portion of the thread near the mounting portion 212 is provided with a sealing ring 2111. The positioning sealing part 211 is used for connecting the sealing cavity 231 of the plunger pump 23, the outer diameter of the positioning sealing part 211 is precisely matched with the inner diameter of the sealing cavity 231, the end part screwed into the sealing cavity 231 is tightly connected with the sealing cavity 231 through threads, and the sealing is sealed through a sealing ring 2111, so that the sealing performance of the adapter 21 is improved, and air leakage is avoided. Further, a mounting portion positioning step 2112 may be provided between the positioning seal portion 211 and the mounting portion 212 to accurately position the height of the adapter 21 itself.

The circumferential surface of the mounting portion 212 is provided with two mounting planes 2121 which are symmetrical to each other and are used for mounting or dismounting the adapter 21. The lance tip adapter portion 213 includes a radial positioning portion 2131, a connecting conical surface 2132, a protrusion 2133 and a plug 2134 in sequence along a direction away from the mounting portion 212. An adapting portion positioning step 214 is provided between the radial positioning portion 2131 and the mounting portion 212, and is used for axially positioning the pipette tip 50, and after the pipette tip 50 is inserted, the radial heights of the pipette tip 50 and the mounting portion 212 are substantially the same. The outer diameter of the radial positioning portion 2131 is matched with the inner diameter of the insertion port of the pipette tip 50, and is used for radially positioning the pipette tip 50. One end of the connecting conical surface 2132 is connected to the radial positioning portion 2131, and the other end is connected to the protrusion 2133; the protrusion 2133 is annular and includes a first tapered surface 2133a and a second tapered surface 2133b, the first tapered surface 2133a connects the connecting tapered surface 2132 and the second tapered surface 2133b, respectively, and the second tapered surface 2133b connects the plug 2134. Thus, the first conical surface 2133a and the second conical surface 2133b both have a guiding function, and the protrusion 2133 can be tightly connected with the inner cavity of the pipette tip 50, so that the sealing property of the connection between the pipette tip 50 and the adapter 21 is ensured. In addition, a sealing ring can be embedded in the protrusion 2133, so that the sealing performance of the connection between the gun head adapter 21 and the gun head is further enhanced. The outer diameter of plug 2134 is smaller than the outer diameter of radial locating portion 2131 to facilitate insertion of pipette tip 50.

Fig. 11 is a schematic structural view of the ejector 40, and fig. 12 is a schematic sectional structural view at XII-XII in fig. 11. The ejector 40 is disposed on the stripper plate 11 and perpendicular to the stripper plate 11, as shown in fig. 11 and 12, the ejector 40 includes an outer sleeve 41, an encapsulating screw 44, an elastic member 43, and an ejector pin 42.

One end of the outer sleeve 41 is provided with a plurality of guide surfaces 411 for guiding insertion into the mounting holes 112 of the stripper plate 11 and also for screwing the ejector 40 to mount or dismount the ejector 40. An ejection cavity extending along the length direction of the outer sleeve 41 is further arranged in the outer sleeve 41. The packaging screw 44 is locked at the opening of the ejection accommodating cavity, the elastic element 43 is positioned in the ejection accommodating cavity and abuts against the packaging screw 44, and the packaging screw 44 packages the elastic element 43 in the ejection accommodating cavity. The thimble 42 has one end protruding from the end of the outer casing 41 opposite to the packaging screw 44 and the other end abutting against the elastic member 43. The outer periphery of the lower end of the outer sleeve 41 is provided with threads, the mounting hole 112 of the stripper plate 11 is internally provided with threads matched with the threads, and the two are assembled to mount the ejector 40 in the mounting hole 112.

When the pipetting mechanism 20 moves close to the pipette tip 50 until the adapter 21 is connected with the pipette tip 50, the thimble 42 abuts against the box body of the pipette tip 50 so that the elastic piece 43 is compressed; when the pipetting mechanism 20 carries the pipette tip 50 to move reversely, the elastic member 43 pushes the cartridge of the pipette tip 50 so that the pipette tip 50 is separated from the cartridge of the pipette tip 50.

Fig. 13 is a schematic structural view of the linear drive mechanism 30, and fig. 14 is a schematic structural view in the direction C in fig. 13. As shown in fig. 13 and 14, the linear driving mechanism 30 includes a linear driving frame 33, a linear driving guide column 31, a linear driving slider 32, and a linear driving motor 34.

The linear driving frame 33 includes a top plate 331, a bottom plate 333, and a connecting column 332, the top plate 331 and the bottom plate 333 are respectively connected to both ends of the connecting column 332 to form a "C" shaped structure, and the pipetting mechanism 20 is movably connected to the connecting column 332. The top plate 331 is provided with a through hole (not shown), and the side surface of the bottom plate 333 facing the top plate 331 is provided with a linear drive bearing 3331. The side of the connection post 332 opposite the linear drive slide 32 is provided with a linear drive rail 35 for connection to the pipetting mechanism 20.

The linear driving guide post 31 is positioned in the linear driving frame 33, and has one end connected to the top plate 331 and the other end connected to the bottom plate 333. A linear drive slide 32 is connected to the pipetting mechanism 20. As another embodiment, the linear driving slider 32 may be provided with a guide hole (not shown) through which the linear driving guide post 31 passes. The linear drive slider 32 is provided with a linear drive nut 321. In the present embodiment, the linear driving motor 34 is a rotary motor, an output shaft of the linear driving motor 34 is connected to the linear driving screw 341 through a through hole of the top plate 331, and the linear driving screw 341 is connected to the linear driving bearing 3331 of the bottom plate 333 through the linear driving nut 321 of the linear driving slider 32.

When the linear driving motor 34 rotates, the linear driving lead screw 341 is driven to rotate, so that the linear driving slider 32 can be driven to move along the linear driving guide column 31, the pipetting mechanism 20 is driven to move along the connecting column 332, and the adapter 21 of the pipetting mechanism 20 is made to move close to the pipette tip 50 until the pipette tip 50 is connected.

The use of the above-described pipetting device is described in detail below.

Firstly, the linear driving motor 34 of the linear driving mechanism 30 rotates, and the linear driving slider 32 moves to drive the whole pipetting mechanism 20 to approach the pipette tip 50 until the adapter 21 of the pipetting mechanism 20 contacts the pipette tip 50 and is inserted into the pipette tip 50 to be connected with the pipette tip 50. At this time, the ejector pin 42 of the ejector 40 abuts against the case of the pipette tip 50 so that the elastic member 43 is compressed.

Then, the linear driving motor 34 of the linear driving mechanism 30 rotates reversely, the linear driving slider 32 moves to drive the whole liquid transfer mechanism 20 to move reversely, and the elastic member 43 pushes against the box body of the pipette tip 50, so that the pipette tip 50 is separated from the box body of the pipette tip 50.

Then, the plunger driver 223 of the plunger pump driving device 22 of the pipetting mechanism 20 rotates, and the plunger 232 is driven by the plunger driving slide block 221 to move along the length direction of the sealed cavity 231 so as to suck or discharge liquid through the pipette tip 50 through the adapter 21, thereby realizing the liquid moving and dispensing operation.

Finally, the stripping motor 124 of the stripping driving device 12 drives the stripping slider 121 to move, so as to drive the stripping plate 11 to approach the pipette tip 50, and the stripping portion 114 successively collides with the end of the pipette tip 50 to withdraw the pipette tip 50 from the adapter 21.

The plurality of adapters 21 of the liquid transfer device can simultaneously obtain the pipette tips 50, and simultaneously perform sampling operation, so that the liquid transfer device is simple in structure, small in size, low in cost, free of damage to the pipette tips, easy to maintain and particularly suitable for automatic sample preparation systems of laboratories such as clinical experiments, scientific research institutions and quarantine systems in hospitals. And the liquid-transfering device has high automation degree, can replace the prior manual operation or semi-automatic operation, reduces the manpower degree, and also avoids the possible errors or infection of manual operation. When the material removing mechanism 10 removes the pipette tips 50, the material removing portion 114 can sequentially push the pipette tips 50, so that the resistance of the material removing plate 11 can be reduced. Moreover, in the material stripping process, the material stripping part 114 successively pushes the pipette tips 50, so that the resistance of the material stripping plate 11 does not change suddenly, and the vibration of the pipetting device in the material stripping process can be reduced.

In the several embodiments provided in the present invention, it should be understood that the disclosed components and structures may be implemented in other ways. It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned. Furthermore, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. Several units or means recited in the system claims may also be implemented by one and the same unit or means in software or hardware. The terms first, second, etc. are used to denote names, but not any particular order.

Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention.

Claims

1. A stripping mechanism for withdrawing a pipette tip from an adapter comprises a stripping plate, the stripping plate comprises a plurality of stripping parts, the stripping parts are provided with a plurality of stripping through holes penetrating through the stripping plate, the stripping through holes are used for sleeving the adapter, and the stripping mechanism is characterized in that,

2. The stripping mechanism as claimed in claim 1, wherein the plurality of stripping portions are at least partially arranged on the side surface of the stripping plate in a step shape.

3. The material removing mechanism according to claim 2, wherein the material removing distance of the material removing portion increases from the middle portion to the two ends, so that when the material removing plate moves close to the pipette tip, the material removing portion sequentially collides with the end portion of the pipette tip from the middle portion to the two ends to withdraw the pipette tip from the adapter.

4. The material removing mechanism according to claim 1, further comprising a material removing driving device connected to the material removing plate for driving the material removing plate to approach or move away from the pipette tip.

5. A pipetting device comprising a pipetting mechanism, characterized in that it further comprises a stripping mechanism according to any one of claims 1 to 4, said pipetting mechanism comprising an adapter, a plunger pump and a plunger pump drive,

6. The pipette device according to claim 5, further comprising an ejector that includes:

7. A pipetting device as recited in claim 5 further comprising a linear drive mechanism comprising:

the linear driving slide block is connected with the liquid transfer mechanism;

8. The pipette device according to claim 5, wherein the stripper mechanism further comprises a limit switch for detecting a distance by which the stripper plate moves.

9. Pipetting device according to claim 5, characterized in that the adapter comprises a cylindrical barrel comprising a positioning seal part, a mounting part and a lance tip adapter part,

10. Pipetting device according to claim 5, wherein the plunger pump drive comprises a plunger drive rack, a plunger drive guide column, a plunger drive slide, a connection block, a guide rail fixing block and a plunger drive;