CN116099582A

CN116099582A - Automatic liquid-transfering device that breaks away from pipette head

Info

Publication number: CN116099582A
Application number: CN202211481168.XA
Authority: CN
Inventors: 陈建兴; 蓝宗钦; 魏超
Original assignee: XIAMEN AMPLLY BIOTECHNOLOGY CO Ltd
Current assignee: XIAMEN AMPLLY BIOTECHNOLOGY CO Ltd
Priority date: 2022-11-24
Filing date: 2022-11-24
Publication date: 2023-05-12

Abstract

The invention provides a liquid dispenser capable of automatically separating from a liquid suction head, and relates to the technical field of liquid dispensers. The pipettor comprises a suction tube assembly, a shell assembly, a telescopic assembly and a head removing assembly. The suction tube assembly consists of a tube body and a piston. The housing assembly is coupled to the barrel. The telescopic component is configured on the shell component and used for driving the piston to move. The telescopic assembly is provided with a first connecting piece connected with the piston and a driving piece connected with the first connecting piece. The first connector is provided with a first protrusion. The head removing assembly comprises a first sliding piece, a second sliding piece and a reverse transmission piece which are in transmission connection. The reversing drive is configured to move the first slider and the second slider in opposite directions. The first slider is provided with a first bar-shaped groove. The first bar-shaped groove is configured to abut against and move along with the first protrusion when the first protrusion moves in a direction away from the cylinder within a first preset range, so that the second slider moves in a direction approaching the liquid suction head, and the liquid suction head is pushed away from the cylinder.

Description

Automatic liquid-transfering device that breaks away from pipette head

Technical Field

The invention relates to the technical field of pipettors, in particular to a pipettor capable of automatically separating from a liquid suction head.

Background

In a laboratory or other setting, liquid is often moved, and a disposable pipette is usually connected to the pipette to aspirate the liquid. The liquid is stored in the pipette head during movement and does not enter the interior of the pipette.

Traditional pipetting devices require manual pipetting head to be bumped onto pipettors when in use, and the pipetting head needs to be manually removed and thrown away after use. After the use, the pipetting head is stained with chemical reagents, which may cause corrosion and other injuries to human bodies. And part of the pipetting devices are connected with the pipetting head through a longer pipeline, so that the dead space is larger, and the pipetting accuracy is reduced.

In view of this, the applicant has studied the prior art and has made the present application.

Disclosure of Invention

The present invention provides a pipette that automatically disengages a pipette head, which aims to ameliorate at least one of the above technical problems.

In order to solve the technical problems, the invention provides a pipettor capable of automatically separating from a liquid suction head, which comprises a suction cylinder assembly, a shell assembly, a telescopic assembly and a head separating assembly.

The suction tube assembly consists of a tube body and a piston. The cylinder body is provided with a cylinder cavity. The piston is arranged in the cylinder cavity in a sealing and sliding way. The cylinder body is used for being jointed with the liquid suction head so that the fluid outside the liquid suction head can flow into the liquid suction head or the fluid in the liquid suction head can be discharged when the piston moves.

The housing assembly is coupled to the barrel.

The telescopic component is configured on the shell component and used for driving the piston to move. The telescopic assembly is provided with a first connecting piece connected with the piston and a driving piece connected with the first connecting piece. The driving piece is used for driving the first connecting piece to move along the axis direction of the piston. The first connector is provided with a first protrusion.

The head removing assembly comprises a first sliding piece and a second sliding piece which are slidably arranged on the shell assembly, and a reverse transmission piece which is connected with the first sliding piece and the second sliding piece in a transmission mode. The reversing drive is configured to move the first slider and the second slider in opposite directions.

The first slider is provided with a first bar-shaped groove. The first bar-shaped groove is configured to abut against and move along with the first protrusion when the first protrusion moves in a direction away from the cylinder within a first preset range, so that the second slider moves in a direction approaching the liquid suction head, and the liquid suction head is pushed away from the cylinder.

In an alternative embodiment, the first slot is further configured such that the first protrusion does not abut the first protrusion when the first protrusion is movable within the second predetermined range.

The first bar-shaped groove is also configured to be capable of abutting against and moving with the first protrusion to move the second slider in a direction away from the liquid suction head when the first protrusion moves in a direction approaching the cylinder body within a third preset range.

In an alternative embodiment, the reversing drive is a gear. The first sliding piece is provided with a first rack part matched with the reverse transmission piece. The second sliding piece is provided with a second rack part matched with the reverse transmission piece.

The first strip-shaped groove is a first strip-shaped hole arranged on the first sliding piece.

In an alternative embodiment, the housing assembly includes a base, a suction cup disposed on the base, and a drive cup. The cylinder body is arranged on the cylinder sucking seat. The driving piece is arranged on the driving seat.

The suction cylinder seat is provided with a vent hole. The suction tube assembly further comprises a connecting tube configured at the vent hole. The connecting tube can be communicated to the cylinder cavity through the vent hole. The connecting pipe is used for being connected to the liquid suction head.

In an alternative embodiment, the cartridge holder is further provided with a detection aperture in communication with the vent aperture. The housing assembly also includes a pressure sensor disposed in the sensing bore.

In an alternative embodiment, the head release assembly further comprises a push head member that fits over the connection tube. The pushing head piece is connected to the second sliding piece and used for pushing the liquid sucking head away from the cylinder body when the second sliding piece moves towards the liquid sucking head.

The head removing assembly further comprises a first guide piece arranged on the head pushing piece. The suction cylinder seat is provided with a first guide hole for embedding the first guide piece.

In an alternative embodiment, the housing assembly further comprises a slide disposed on the suction cup and the drive cup. The slide seat is provided with a slide groove. The first slider and the second slider are respectively provided with a sliding portion capable of sliding in the slide groove.

In an alternative embodiment, the housing assembly further comprises a second guide member configured to the drive socket. The second guide piece is sleeved on the first connecting piece. The second guide member is provided with a second guide hole. The first protrusion is a first deflector rod configured on the first connecting piece. The first deflector rod extends outwards from the first connecting piece and penetrates through the second guide hole to be embedded into the first strip-shaped groove.

The second guide member includes at least two second guide holes. The telescopic assembly further comprises a guide rod configured on the first connecting piece. The guide rod is embedded in the second guide hole.

In an alternative embodiment, the drive member is a motor with an output shaft provided with a screw. The first connector is configured as a tubular geometry and is sleeved on the screw.

The telescoping assembly further includes a threaded sleeve disposed on the first connector. The threaded sleeve is sleeved on the screw rod.

By adopting the technical scheme, the invention can obtain the following technical effects:

according to the embodiment of the invention, after the external liquid is sucked into the liquid suction head, the first connecting piece can be continuously driven to move, so that the first bulge drives the head removing assembly to push the liquid suction head outwards, the liquid suction head is automatically separated from the liquid suction device, the liquid suction head is not manually removed, and the human body is prevented from contacting with chemical reagents, so that the liquid suction head has good practical significance.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some examples of the present invention and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is an isometric view of a pipette.

Fig. 2 is a first exploded view of the pipette.

Fig. 3 is a second exploded view of the pipette.

Fig. 4 is a semi-sectional view of a pipette.

The marks in the figure: 1-shell component, 2-driving seat, 3-second guide piece, 4-base, 5-slide seat, 6-suction cylinder seat, 7-second guide hole, 8-spout, 9-slider, 10-expansion component, 11-driving piece, 12-thread bush, 13-guide bar, 14-first driving lever, 15-first connecting piece, 17-suction cylinder component, 18-piston, 19-barrel, 20-connecting pipe, 21-suction head, 24-vent, 25-first guide hole, 26-head-removing component, 27-first bar slot, 28-first slider, 29-reverse transmission piece, 30-second slider, 31-first guide piece, 32-push head piece, 33-detection hole.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are some, but not all, of the embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, are intended to fall within the scope of the present invention. Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, are intended to fall within the scope of the present invention.

Referring now to fig. 1-4, an embodiment of the present invention provides a pipette capable of automatically disengaging a pipette head, comprising a pipette cartridge assembly 17, a housing assembly 1, a telescoping assembly 10, and a pipette head assembly 26.

The suction barrel assembly 17 is composed of a barrel 19 and a piston 18. The barrel 19 is provided with a barrel cavity. The piston 18 is sealingly slidably disposed within the barrel cavity. The barrel 19 is used to be connected to the liquid suction head 21, so that the liquid outside the liquid suction head 21 can flow into the liquid suction head 21 or the liquid in the liquid suction head 21 can be discharged when the piston 18 moves. The housing assembly 1 is joined to the barrel 19.

The telescopic assembly 10 is disposed on the housing assembly 1 for driving the piston 18 to move. The telescopic assembly 10 is provided with a first coupling member 15 coupled to a piston 18, and a driving member 11 coupled to the first coupling member 15. The driving member 11 is configured to drive the first connecting member 15 to move along the axial direction of the piston 18. The first connecting member 15 is provided with a first protrusion.

The head-removing assembly 26 includes a first slider 28 and a second slider 30 slidably disposed in the housing assembly 1, and a reversing drive 29 drivingly connected to the first slider and the second slider. The reversing gear 29 is configured to enable the first slider and the second slider to move in opposite directions.

The first slider is provided with a first bar-shaped groove 27. The first bar-shaped groove 27 is configured to be able to abut against and move with the first projection when the first projection moves in a direction away from the cylinder 19 within a first preset range, so that the second slider 30 moves in a direction approaching the liquid-sucking head 21, thereby pushing the liquid-sucking head 21 away from the cylinder 19.

Specifically, in the pipette according to the embodiment of the present invention, the suction cylinder assembly 17 is divided into an upper working section and a lower working section, which are respectively used for two working tasks, and when the piston 18 moves in the lower working section, the fluid is sucked or discharged by the suction head 21 according to the action of the piston 18; when the piston 18 moves in the upper working space in the direction away from the cylinder 19, the first connecting piece 15 can be driven to move, so that the first bulge drives the head removing assembly 26 to push the liquid suction head 21 outwards, the liquid suction head 21 is automatically separated from the liquid suction device, the liquid suction head 21 is not manually removed, the human body is prevented from contacting with chemical reagents, and the liquid suction device has good practical significance.

In an alternative embodiment of the present invention, as shown in fig. 4, the first bar-shaped groove 27 is further configured so that the first protrusion does not abut against the first protrusion when the first protrusion moves within the second preset range.

The first bar-shaped groove 27 is also configured to be able to abut against and move with the first projection to move the second slider 30 in a direction away from the liquid-sucking head 21 when the first projection moves in a direction approaching the cylinder 19 within a third preset range.

Specifically, the first connection 15 is driven only by abutment of the first protrusion. When the first protrusion abuts against the upper wall of the first strip-shaped groove 27 and continues to move upwards, the first sliding piece 28 is driven to move upwards, so that the second sliding piece 30 moves downwards to push the liquid suction head 21 away from the barrel 19. When the first protrusion abuts against the lower wall of the first bar-shaped groove 27, the first sliding member 28 is driven to move downwards by continuing to move downwards, so that the second movable member moves upwards, and the position for installing the liquid suction head 21 is exposed.

In the present embodiment, of the upper and lower working sections of the suction tube assembly 17, the upper working section is a first preset range within which the first protrusion can contact the upper wall of the first bar-shaped groove 27. The lower working space is further divided into a second preset range and a third preset range, in which the first protrusion is free to move without contacting the upper wall or the lower wall of the first bar-shaped groove 27. The first protrusion can contact the lower wall of the first bar-shaped groove 27 within the third preset range.

In other embodiments, the elastic member may be disposed to abut against the first sliding member 28 so as to have a tendency to move toward the barrel 19, so that the first sliding member 28 can abut against the upper wall of the first bar-shaped groove 27 within the first preset range, and the first sliding member 28 and the first protrusion move synchronously when the first protrusion moves within the first preset range. The third preset range is combined with the function to be realized by the first preset range, so that the lower working interval only needs to set the second preset range.

In an alternative embodiment of the present invention, based on the above embodiment, the pipette further comprises a control assembly; the control assembly comprises a controller electrically connected to the driving piece 11, a first position sensor, a first rising switch, a second rising switch and a first falling switch which are electrically connected to the controller; the first position sensor is configured on the housing assembly 1 and is used for detecting whether the first protrusion is in a first preset range; the first rising switch is used for controlling the first bulge to move towards a direction away from the cylinder body 19 outside the first preset range; the second rising switch is used for controlling the first bulge to move towards a direction away from the cylinder body 19 within the first preset range; the first lowering switch is configured to drive the first protrusion to move toward a direction approaching the barrel 19.

Specifically, the first protrusion is controlled to be far away from the barrel 19 outside and within the first preset range by the first rising switch and the second rising switch, respectively. It is possible to avoid the situation other than pushing the liquid suction head 21 away from the cylinder 19 when the liquid suction is performed, because the first projection enters the first preset range by pressing the up switch for a long time.

Preferably, the first ascent switch can only control the first protrusion to move in a direction away from the barrel 19 outside the first preset range; the second ascent switch can always control the first protrusion to move in a direction away from the barrel 19.

Specifically, the second rising switch can always control the first protrusion to move towards the direction away from the barrel 19, so that the tedious operation of continuously pressing the first rising switch to move the first protrusion to the boundary of the first preset range and then pressing the second rising switch to move the first protrusion into the first preset range is avoided. Preferably, the speed of movement of the first protrusion at the time of the second rising switch control is greater than that at the time of the first rising switch control.

As shown in fig. 2 and 3, in an alternative embodiment of the present invention, the reversing transmission 29 is a gear, based on the above-described embodiment. The first slider 28 is provided with a first rack portion adapted to the reversing gear 29. The second slider 30 is provided with a second rack portion adapted to the reversing gear 29. The first slot 27 is a first slot hole provided in the first slider.

Specifically, the first sliding piece 28 and the second sliding piece 30 are reversely moved through the gear-rack structure, when the first bulge is far away from the cylinder 19, the first sliding piece 28 is driven to move, so that the second sliding piece 30 moves towards the direction of the liquid suction head 21 and pushes the liquid suction head 21 away from the cylinder 19, and the structure is simple and the volume is small.

As shown in fig. 2 and 3, in an alternative embodiment of the present invention, the housing assembly 1 includes a base 4, a suction cup 6 disposed on the base 4, and a driving cup 2. The cylinder 19 is disposed on the suction cylinder seat 6. The driving element 11 is disposed on the driving seat 2. Preferably, the suction cup 6 is provided with a vent 24. The suction tube assembly 17 further includes a connection tube 20 disposed at the vent hole 24. The connection tube 20 can communicate to the cylinder chamber through the vent hole 24. The connection tube 20 is adapted to be coupled to the pipette head 21.

Specifically, the suction tube assembly 17 and the suction head 21 are coaxially disposed. And the suction tube assembly 17 is positioned right above the liquid suction head 21, and the suction tube assembly and the liquid suction head are close to each other, so that the volume of a dead space (or referred to as an instrument dead space) is extremely large, the liquid taking and discharging response is improved, and the sample adding precision is improved. Preferably, the chassis 4 is integrally provided with the housing of the syringe assembly.

As shown in fig. 4, in an alternative embodiment of the present invention, the suction tube holder 6 is further provided with a detection hole 33 communicating with the vent hole 24, on the basis of the above-described embodiment. The housing assembly 1 further includes a pressure sensor disposed in the detection hole 33.

Specifically, the pressure sensor is electrically connected to the controller. It will be appreciated that the air pressure within the cartridge chamber varies as the pipette aspirates different forms of fluid. The controller is configured to determine a change in the substance being suctioned based on the air pressure detected by the pressure sensor. For example: the substance is sucked from gas to liquid or from liquid to gas.

As shown in fig. 2 and 3, in an alternative embodiment of the present invention, the head removing assembly 26 further includes a head pushing member 32 sleeved on the connection pipe 20. The pusher 32 is coupled to the second slider 30 for pushing the pipette head 21 away from the barrel 19 when the second slider 30 moves in the direction of the pipette head 21. The head release assembly 26 further includes a first guide 31 disposed on the pusher 32. The suction cup 6 is provided with a first guide hole 25 into which the first guide is inserted.

Specifically, the push head piece 32 is sleeved on the connecting pipe 20, so that the liquid suction head 21 is uniformly applied with force in the whole circle in the downward moving process, and the push head piece has good practical significance.

In an alternative embodiment of the present invention, based on the above embodiment, the control assembly further includes a second position sensor electrically connected to the controller; the second position sensor is configured on the housing assembly 1, and is used for detecting whether the push head piece 32 is at an initial position; the second ascent switch is configured to control the first protrusion to move in a direction away from the barrel 19 when the push head piece 32 is in the initial position.

Specifically, when the pusher 32 is in the initial position, the portion of the connecting tube 20 for engaging the pipette 21 is exposed. When the pusher 32 moves downward from the initial position, it can abut on the pipette head 21 to push the pipette head 21 away from the connection tube 20.

As shown in fig. 2 and 3, in an alternative embodiment of the present invention, the housing assembly 1 further includes a slide 5 disposed on the suction cup 6 and the driving cup 2. The slide 5 is provided with a slide slot 8. The first slider 28 and the second slider 30 are each provided with a slide portion 9 slidable in the chute 8.

Specifically, the sliding seat 5 and the base 4 are respectively arranged at two sides of the suction tube assembly 17, so that the suction tube assembly 17 and the telescopic assembly 10 can be protected, damage during collision is prevented, and the durability of the pipette is greatly improved.

As shown in fig. 2 and 3, in an alternative embodiment of the present invention, the driving member 11 is a motor whose output shaft is provided with a screw. The first connection 15 is constructed as a tubular geometry and is fitted over the threaded rod. The telescopic assembly 10 further comprises a threaded sleeve 12 arranged at the first connection 15. The thread bush 12 is sleeved on the screw.

Preferably, the housing assembly 1 further comprises a second guide 3 arranged at the drive seat 2. The second guide member 3 is sleeved on the first connecting member 15. The second guide 3 is provided with a second guide hole 7. The first protrusion is a first lever 14 disposed on the first connecting member 15. The first lever 14 extends outwardly from the first coupling member 15 and passes through the second guide hole 7 to be fitted into the first bar-shaped groove 27.

The second guide 3 comprises at least two second guide holes 7. The telescopic assembly 10 further comprises a guide bar 13 arranged at the first connection 15. The guide rod 13 is inserted into the second guide hole 7.

Specifically, the second guide member 3 is sleeved outside the first connecting member 15, so that the first connecting member 15 can be limited to move only along the axial direction; the first link 15 can be restricted from rotating by the first shift lever 14 and the guide lever 13 on the first link 15 cooperating with the second guide hole 7 on the second guide 3. So that the threaded sleeve 12 can move up and down with the first connecting piece 15 when the screw is rotated. The radial dimension of the structure is smaller, so that the whole liquid transfer device is in a columnar structure, and the handheld operation is convenient. The liquid transfer (sucking liquid into the liquid suction head 21) and the liquid withdrawal (pushing the liquid suction head 21 away from the cylinder 19) are divided into an upper section and a lower section, the action stroke is collision-free, the volume of a dead cavity of equipment in the liquid transfer device is reduced to the greatest extent, and the extremely high liquid transfer precision is obtained. And the pipetting action of the suction tube assembly 17 and the action of the push head assembly are controlled by adopting one motor, so that the integration degree is high.

The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, and various modifications and variations may be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A liquid-transfering device capable of automatically separating from a liquid-transfering head, which comprises a liquid-transfering tube component (17) formed from a tube body (19) and a piston (18); the cylinder body (19) is provided with a cylinder cavity; the piston (18) is arranged in the cylinder cavity in a sealing and sliding manner; the cylinder body (19) is used for being jointed with the liquid suction head (21) so that the fluid outside the liquid suction head (21) can flow into the liquid suction head (21) or the fluid in the liquid suction head (21) can be discharged when the piston (18) moves; characterized by further comprising:

a housing assembly (1) joined to the barrel (19);

a telescopic assembly (10) arranged on the shell assembly (1) and used for driving the piston (18) to move; -said telescopic assembly (10) is provided with a first connection (15) coupled to said piston (18), and with a driving member (11) coupled to said first connection (15); the driving piece (11) is used for driving the first connecting piece (15) to move along the axial direction of the piston (18); the first connecting piece (15) is provided with a first bulge;

a head-off assembly (26) comprising a first slider (28) and a second slider (30) slidably arranged in the housing assembly (1), and a reversing transmission member (29) drivingly connected to the first slider and the second slider; -the reversing drive (29) is configured to move the first and second slides in opposite directions;

the first slider is provided with a first slot (27); the first strip-shaped groove (27) is configured so that when the first protrusion moves in a direction away from the cylinder (19) within a first preset range, the first protrusion can abut against and move along with the first protrusion, so that the second sliding piece (30) moves in a direction approaching the liquid suction head (21), and the liquid suction head (21) is pushed away from the cylinder (19).

2. A pipette automatically disengaged from a pipette head as recited in claim 1, wherein the first bar-shaped groove (27) is further configured so that the first projection does not abut the first projection when the first projection is movable within a second predetermined range;

the first strip-shaped groove (27) is also configured to be capable of abutting against and moving along with the first protrusion when the first protrusion moves in a direction approaching the barrel (19) within a third preset range, so that the second slider (30) moves in a direction away from the liquid suction head (21).

3. A pipette automatically disengaged from a pipette head as recited in claim 1, wherein said reversing drive (29) is a gear; the first sliding piece (28) is provided with a first rack part matched with the reverse transmission piece (29); the second sliding piece (30) is provided with a second rack part matched with the reverse transmission piece (29);

the first strip-shaped groove (27) is a first strip-shaped hole arranged on the first sliding piece.

4. A pipette automatically disengaged from a pipette head according to claim 1, wherein the housing assembly (1) comprises a base (4), a suction cartridge seat (6) arranged on the base (4), and a drive seat (2); the cylinder body (19) is arranged on the suction cylinder seat (6); the driving piece (11) is arranged on the driving seat (2);

the suction cylinder seat (6) is provided with a vent hole (24); the suction tube assembly (17) further comprises a connecting tube (20) arranged at the vent hole (24); the connecting tube (20) can be communicated to the cylinder cavity through the vent hole (24); the connecting pipe (20) is used for being connected with the liquid suction head (21).

5. A pipette automatically disengaged from a pipette head according to claim 4, wherein the pipette holder (6) is further provided with a detection hole (33) communicating with the vent hole (24); the housing assembly (1) further comprises a pressure sensor arranged in the detection hole (33).

6. A pipette automatically disengaged from a pipette head as recited in claim 4 wherein said pipette head assembly (26) further comprises a pusher (32) nested within said connecting tube (20); the pushing head piece (32) is jointed with the second sliding piece (30) and is used for pushing the liquid sucking head (21) away from the cylinder body (19) when the second sliding piece (30) moves towards the liquid sucking head (21);

the head-removing assembly (26) further comprises a first guide (31) arranged on the head pushing piece (32); the suction tube seat (6) is provided with a first guide hole (25) into which the first guide piece is embedded.

7. A pipette automatically disengaged from a pipette head according to claim 4, wherein the housing assembly (1) further comprises a slide (5) arranged on the pipette holder (6) and the drive holder (2); the sliding seat (5) is provided with a sliding groove (8); the first slider (28) and the second slider (30) are each provided with a sliding portion (9) that is slidable in the chute (8).

8. A pipette automatically disengaged from a pipette head according to claim 4, wherein the housing assembly (1) further comprises a second guide (3) arranged on the drive socket (2); the second guide piece (3) is sleeved on the first connecting piece (15); the second guide piece (3) is provided with a second guide hole (7); the first bulge is a first deflector rod (14) arranged on the first connecting piece (15); the first deflector rod (14) extends outwards from the first connecting piece (15) and penetrates through the second guide hole (7) to be embedded into the first strip-shaped groove (27);

the second guide (3) comprises at least two second guide holes (7); the telescopic assembly (10) further comprises a guide rod (13) arranged on the first connecting piece (15); the guide rod (13) is embedded in the second guide hole (7).

9. A pipette automatically disengaged from a pipette head according to any one of claims 1 to 8, wherein the driving member (11) is a motor with an output shaft provided with a screw; the first connecting piece (15) is configured as a tubular geometry and is sleeved on the screw;

the telescopic assembly (10) further comprises a threaded sleeve (12) arranged on the first connecting piece (15); the thread sleeve (12) is sleeved on the screw rod.