CN220759295U

CN220759295U - Liquid transfer device

Info

Publication number: CN220759295U
Application number: CN202322303169.1U
Authority: CN
Inventors: 郭闯; 李明; 凌宇球; 黄震宇
Original assignee: Suzhou Patikole Intelligent Technology Co ltd
Current assignee: Suzhou Patikole Intelligent Technology Co ltd
Priority date: 2023-08-25
Filing date: 2023-08-25
Publication date: 2024-04-12
Anticipated expiration: 2033-08-25

Abstract

The utility model discloses a liquid transfer device, which comprises a piston cylinder, a plunger structure, a stepping motor, a screw rod, a linear guide rod and a guide block, wherein a connecting through hole is formed in the guide block, one end of the linear guide rod is arranged in the connecting through hole in a penetrating manner and can move along a first direction relative to the guide block, the other end of the linear guide rod is connected with the stepping motor, and the plunger structure is connected with the guide block. The lead screw is in threaded connection with the guide block and can drive the guide block to move along the first direction. According to the utility model, accurate pipetting is realized through the cooperation of the guide block, the linear guide rod, the stepping motor and the screw rod, all the components are sequentially arranged along the first direction, and when the pipetting range needs to be enlarged, only the sectional area of the pipetting device perpendicular to the first direction needs to be slightly enlarged, so that the whole volume of the pipetting device is not huge and is not bulky.

Description

Liquid transfer device

Technical Field

The utility model relates to the technical field of liquid removal, in particular to a liquid dispenser.

Background

Pipetting is a common operation in the fields of physics, biology, chemistry and the like, and for the purposes of sampling, proportioning and the like, a small amount of liquid is often required to be removed from a certain liquid, and people perform pipetting through a pipetting device.

Because the pipettor that needs manual operation to remove liquid is when needs a large amount of removal operations, the staff is tired easily, leads to the liquid transfer in-process to appear wrong, and then can influence test or ratio result. A pipette for an automated pipetting device is thus presented.

All pipettors for automatic pipetting equipment in the market at present adopt linear guide rail, guide block and lead screw, step motor, piston cylinder, piston rod to cooperate to accomplish accurate pipetting, and linear guide rod and lead screw all set up in the side of piston cylinder, and in consideration of the cost problem, the pipettor volume that cooperates automatic pipetting equipment to carry out pipetting can not be too big, this just leads to the piston cylinder to have to reduce, therefore the range of the pipettor that is used for automatic pipetting equipment in the market at present is 1ml, need expand the range of pipettor with the volume of piston cylinder and other subassembly rather than complex, and the pipettor that makes will be whole huge and bloated, and the cost is also higher.

To this end, the utility model provides a pipette of novel structure.

Disclosure of Invention

To overcome the above-mentioned drawbacks, an object of the present utility model is to provide a pipette.

In order to achieve the above purpose, the utility model adopts the following technical scheme: a pipette, comprising

A piston assembly comprising a piston cylinder and a plunger structure comprising a first end and a second end in a first direction; the first end part is positioned in the piston cylinder and can reciprocate in the piston cylinder, and the second end part is positioned outside the piston cylinder;

the driving assembly comprises a stepping motor and a screw rod, and the stepping motor is connected with the screw rod and can drive the screw rod to rotate positively or reversely;

the guide assembly comprises a linear guide rod and a guide block, a connecting through hole is formed in the guide block, one end of the linear guide rod penetrates through the connecting through hole and can move along a first direction relative to the guide block, the other end of the linear guide rod is connected with the stepping motor, and the second end of the plunger structure is connected with the guide block.

The lead screw is in threaded connection with the guide block and can drive the guide block to move along the first direction.

According to the liquid transfer device provided by the utility model, the screw rod is driven to rotate positively or reversely through the stepping motor, the screw rod is in threaded connection with the guide block, the stepping motor converts an electric pulse signal into angular displacement, and then the electric pulse signal is converted into linear displacement of the guide block through the screw rod, so that the plunger structure is driven to reciprocate in the piston cylinder, and the volume of the piston cylinder is changed to realize suction and discharge of liquid; the liquid is moved and fetched mechanically by matching the stepping motor with the screw rod, so that the working strength of workers is reduced, and the workload of the workers is reduced; the volume of the piston assembly can be accurately controlled through the cooperation of the guide block and the linear guide rod with the stepping motor and the screw rod, so that the suction amount of liquid is accurately controlled, accurate pipetting is realized, and the accuracy of the pipettor is ensured; through setting gradually piston assembly, direction subassembly, drive assembly along first direction, when needs enlarge the pipettor range, only need slightly enlarge the pipettor perpendicular to the sectional area of first direction can, can not lead to the holistic huge bulk of pipettor.

Further, the pipette further comprises a suction head assembly for taking and placing liquid, the suction head assembly comprises a suction head, a suction head mounting nozzle and a suction head mounting nozzle pressing plate, the suction head mounting nozzle is connected with one end of the piston cylinder and is fixed through the suction head mounting nozzle pressing plate, and the suction head is connected with the suction head mounting nozzle.

The disassembly and the installation of the suction head are convenient.

Further, the pipette further comprises a housing assembly, the housing assembly comprises a fixed shell, the fixed shell is provided with a first shell part and a second shell part along a first direction, the suction head assembly is arranged on the first shell part, and the driving assembly is arranged on the second shell part; the fixed shell is provided with openings which are convenient for installing and detaching other components of the liquid transfer device, and each opening is provided with a cover plate.

The fixed shell can fix each subassembly of pipettor, and the setting of fixed shell upper shed is convenient for the installation and the dismantlement of each subassembly of pipettor, and the apron of setting in each opening part can be dustproof.

Further, the pipettor still includes the needle subassembly that moves back, the needle subassembly that moves back includes to move back needle storehouse, moves back needle ring, axle sleeve and moves back needle bar, move back needle ring cover and establish on the suction head and through axle sleeve and suction head interference fit, move back needle storehouse setting in the needle ring outside that moves back, move back needle bar and move back needle ring and be connected, move back the axis of needle bar with the axis of piston rod is parallel, move back the needle ring and be close to gradually at the guide block, contact and promote when moving back the needle bar along the first direction can drive the suction head and break away from the suction head installing mouth gradually.

The suction head is separated from the suction head mounting nozzle after the pipetting is completed or when the suction head needs to be replaced through the needle withdrawing assembly, so that the suction head is automatically separated.

Further, the pipette further comprises a sensor assembly, the sensor assembly comprises a sensor circuit board, a pressure sensor, a first photoelectric sensor, a second photoelectric sensor, a third photoelectric sensor, a first sensing piece and a second sensing piece, the pressure sensor, the first photoelectric sensor, the second photoelectric sensor and the third photoelectric sensor are sequentially arranged on the sensor circuit board along a first direction, and the first sensing piece is connected with the needle withdrawing rod and can move along the first direction along with the movement of the needle withdrawing rod; the second sensing piece is connected with the guide block and can move along a first direction along with the movement of the guide block, and the pressure sensor is connected with the piston cylinder and used for monitoring the liquid pressure in the suction head to judge whether the liquid is sucked into the suction head or not and the liquid quantity in the suction head; the first photoelectric sensor is used for monitoring the position of the first sensing piece to judge whether the suction head is installed in place or not; the second photoelectric sensor and the third photoelectric sensor are used for monitoring the position of the second sensing piece to judge the working state of the stepping motor.

The sensor assembly can monitor the liquid pressure in the suction head of the liquid dispenser and the condition of the driving assembly in the liquid dispenser.

Further, the pipette further comprises a plug wire assembly, the plug wire assembly comprises a first plug wire assembly and a second plug wire assembly, one end of the first plug wire assembly is connected with the sensor circuit board, and the other end of the first plug wire assembly is connected with the control mechanism or the power supply assembly; one end of the second plug wire assembly is connected with the stepping motor, and the other end of the second plug wire assembly is connected with the control mechanism or the power supply assembly.

The sensor circuit board is connected with the control console or the power supply assembly through the plug wire assembly, so that the sensor circuit board is electrically connected with the control console or the power supply assembly; the stepping motor is connected with the control console or the power supply assembly through the plug wire assembly, so that the stepping motor is electrically connected with the control console or the power supply assembly.

Furthermore, a first O-shaped sealing ring is arranged at the joint of the suction head and the suction head mounting nozzle, and the first O-shaped sealing ring is sleeved on the suction head.

The air tightness of the joint of the suction head and the suction head mounting nozzle is ensured by arranging the O-shaped sealing ring.

Further, a second O-shaped sealing ring is arranged at the joint of the suction head mounting nozzle and the piston cylinder, and the second O-shaped sealing ring is sleeved on the suction head mounting nozzle.

The air tightness of the joint of the suction head mounting nozzle and the piston cylinder is ensured by arranging the O-shaped sealing ring.

Further, the plunger structure comprises a piston rod, a piston gland and a V-shaped sealing element, wherein the piston gland is sleeved on the piston rod and is positioned between the piston rod and the piston cylinder, and the V-shaped sealing element is sleeved on the piston rod and the piston gland.

The volume of the cylinder body is controlled through the plunger structure, so that the volume of the removed liquid is controlled; the V-shaped sealing piece is used for sealing, so that the air tightness between the piston cylinder and the piston rod is better, and the plunger structure is more stable when in reciprocating motion.

Drawings

FIG. 1 is a schematic side view of an embodiment of the present utility model;

FIG. 2 is a schematic diagram illustrating an internal structure of an embodiment of the present utility model;

FIG. 3 is an exploded view of an embodiment of the present utility model;

FIG. 4 is a schematic side view of a plunger structure according to an embodiment of the present utility model;

FIG. 5 is a schematic view of a guide block according to an embodiment of the present utility model;

FIG. 6 is a schematic diagram of a guiding assembly-driving assembly according to an embodiment of the present utility model;

fig. 7 is a schematic view of a fixing case according to an embodiment of the utility model.

In the figure: 11. suction head 12, suction head mounting nozzle 13, suction head mounting nozzle pressing plate

21. Piston cylinder 22, first end 23, second end 221, piston rod 222, piston gland 223, v-seal

31. Step motor 32, screw rod 321, screw rod nut 33 and step motor mounting seat

41. Straight guide rod 42, guide block 421, connecting through hole 422, screw nut fixing hole

51. Sensor circuit board 52, pressure sensor 53, first photoelectric sensor 54, second photoelectric sensor 55, third photoelectric sensor 56, first sensing piece 57, second sensing piece

61. First plug wire assembly 62. Second plug wire assembly

71. The fixing case 711, the first case 712, the second case 713, the first opening 714, the second opening 715, the third opening 716, the fourth opening 72, the side cover 73, the side cover 74, the front cover 75, and the fixing back

81. Needle-withdrawing bin 82, needle-withdrawing ring 83, needle-withdrawing rod 84, shaft sleeve 85, first limit rod 86, compression spring 87 and second limit rod

9. First O-ring seal 10. Second O-ring seal

Detailed Description

In order to make the present application solution better understood by those skilled in the art, the following description will be made in detail and with reference to the accompanying drawings in the embodiments of the present application, it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe the embodiments of the present application described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In the present application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are used primarily to better describe the present application and its embodiments and are not intended to limit the indicated device, element or component to a particular orientation or to be constructed and operated in a particular orientation.

Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.

In addition, the term "plurality" shall mean two as well as more than two.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

The liquid dispenser in the embodiment is used for automatic liquid dispensing equipment, and the control mechanism controls the movement mechanism to drive the liquid dispenser in the embodiment to suck liquid to the liquid taking area and discharge liquid to the liquid discharging area.

When the range of the liquid transfer device is 5ml, the liquid transfer device is not excessively large and bulky, and can be well adapted to common automatic liquid transfer equipment.

With continued reference to fig. 1-3, the present embodiment provides a 5ml pipette including a tip assembly, a piston assembly, a drive assembly, a guide assembly, a sensor assembly, a wire insertion assembly, a housing assembly, and a needle withdrawal assembly;

referring to fig. 3, the suction head assembly is used for taking and discharging liquid, and comprises a suction head 11, a suction head mounting nozzle 12 and a suction head mounting nozzle pressing plate 13, wherein the suction head 11 is connected with the suction head mounting nozzle 12;

the piston assembly comprises a piston cylinder 21 and a plunger structure, a suction head mounting nozzle 12 is connected with one end of the piston cylinder 21 and is fixed through a suction head mounting nozzle pressing plate 13, and a second O-shaped sealing ring 10 is sleeved on the suction head mounting nozzle 12 positioned at the joint of the suction head mounting nozzle 12 and the piston cylinder 21; referring to fig. 4, the plunger structure includes a first end 22 and a second end 23 in a first direction, the first end of the plunger structure including a piston rod 221, a piston gland 222 sleeved on the piston rod 221 and located between the piston cylinder 21 and the piston rod 221, and a V-shaped seal 223 sleeved on the piston gland 222 and the piston rod 221; the second end 23 of the plunger structure is connected to the guide block 42;

the V-seal 223 includes three components, a support ring, a seal ring, and a compression ring.

The guide assembly is arranged between the piston assembly and the driving assembly, the guide assembly comprises a guide block 42 and three linear guide rods 41, referring to fig. 5, a connecting through hole 421 and a screw nut fixing hole 422 are formed in the guide block 42, one end of each linear guide rod 41 is arranged in the connecting through hole 421 in a penetrating manner and can move along a first direction relative to the guide block 42, the central axes of the three linear guide rods 41 are parallel to the central axis of the screw rod 32 and distributed along the circumferential direction of the screw rod 32, and the linear guide rods 41 are distributed along the circumferential direction of the screw rod 32, so that the stability of a pipetting process can be ensured, and accurate pipetting can be always kept; referring to fig. 6, a screw rod 32 is in threaded connection with a screw rod nut 321, the screw rod nut 321 is fixed in a screw rod nut fixing hole 422, a stepping motor 31 converts an electric pulse signal into angular displacement, and then the angular displacement is converted into linear displacement of the screw rod nut 321 and a guide block 42 through the screw rod 32, so that a plunger structure is driven to reciprocate in a piston cylinder 21, and the volume of the piston cylinder 21 is changed to realize suction and discharge of liquid.

The screw 32 may be directly screwed to the guide block 42.

The driving assembly comprises a stepping motor 31 and a screw rod 32, wherein the output end of the stepping motor 31 is connected with the screw rod 32 and can drive the screw rod 32 to rotate positively or reversely, when the stepping motor 31 drives the screw rod 32 to rotate positively, the guide block 42 is close to the bottom of the piston cylinder 21 along a first direction, the first end 22 of the plunger structure is gradually close to the bottom of the piston cylinder, and the inner volume of the piston cylinder is reduced; when the stepper motor 31 drives the screw rod 32 to reversely rotate, the guide block 42 is far away from the bottom of the piston cylinder along the first direction, the first end 22 of the plunger structure is gradually far away from the bottom of the piston cylinder, the inner volume of the piston cylinder is increased, and the stepper motor 31 is electrically connected with the control mechanism through the second plug wire assembly 62.

The number of linear guides includes, but is not limited to, three.

Referring to fig. 1, the housing assembly includes a stationary housing 71, and referring to fig. 7, the stationary housing 71 has a first housing part 711 and a second housing part 712 along a first direction, the suction head assembly is disposed at the first housing part 711, and the driving assembly is disposed at the second housing part 712; a first opening 713 for facilitating the installation and the disassembly of the piston assembly and a second opening 714 for facilitating the disassembly and the installation of the guide assembly are formed in the side face of the fixed shell 71, a side cover plate 73 is arranged at the first opening, and a side cover plate 72 is arranged at the second opening; the front surface of the fixed shell is provided with a third opening 715 which is convenient for the assembly and disassembly of the sensor, and a front cover plate 74 is arranged at the third opening; the back of the fixed shell is provided with a fourth opening 716, and a fixed back plate 75 is arranged at the fourth opening. The fixed housing can fix the piston assembly, the suction head assembly, the sensor assembly, the guide assembly and the driving assembly, and the stepping motor 31 is connected with the fixed housing 71 through the stepping motor mount 33.

With continued reference to fig. 2, the sensor assembly includes a sensor circuit board 51, a pressure sensor 52, a first photosensor 53, a second photosensor 54, a third photosensor 55, a first sensing piece 56, and a second sensing piece 57, the pressure sensor 52, the first photosensor 53, the second photosensor 54, and the third photosensor 55 being sequentially disposed on the sensor circuit board 51 along a first direction, the first sensing piece 56 being connected to the needle retracting lever 83 and being movable along the first direction along with the needle retracting lever 83; the second sensing piece 57 is connected with the guide block 42 and can move along the first direction along with the guide block 42; the sensor circuit board 51 is electrically connected to the control mechanism through a first wire insertion assembly 61.

The pressure sensor 51 is used for monitoring an actual pressure value in the suction head 11, and when the actual pressure value is smaller than a minimum pressure value (a minimum pressure value of liquid in the suction head 11), determining that the suction head is empty (not sucking liquid, only sucking air); the actual liquid level in the suction head can also be calculated by calculating the actual pressure value (the pressure at the end of the suction head 11 where the liquid is remote from the cylinder of the piston cylinder, i.e. the liquid bottom pressure) monitored by the pressure sensor 51, in combination with the specific shape of the suction head 11.

The first photoelectric sensor 53 monitors the position of the first sensing piece 56 to determine whether the suction head 11 is in place, and when the first photoelectric sensor 53 monitors the first sensing piece 56, the suction head 11 is in place;

the second photosensor 54, the third photosensor 55 and the second sensing piece 57 are combined for monitoring the state of pipetting;

before the start of pipetting, the position of the second sensor piece 57 is monitored by the second photosensor 54 to determine whether the guide block 42 is located at the origin position, and a preliminary state of pipetting (the origin is the origin of pipetting, and the amount of pipetting is set as needed).

The third photoelectric sensor 55 monitors the position of the guide block by the position of the second sensing piece 57 to determine whether or not the angular displacement of the reverse rotation of the stepping motor reaches the limit, and when the angular displacement of the reverse rotation of the stepping motor reaches the limit, it controls the stepping motor to stop the reverse rotation to prevent the jamming.

The needle withdrawing assembly comprises a needle withdrawing bin 81, a needle withdrawing ring 82, a shaft sleeve 84 and a needle withdrawing rod 83, wherein the needle withdrawing ring 82 is sleeved on the suction head and in interference fit with the suction head 11 through the shaft sleeve 84, the needle withdrawing bin 81 is arranged at the outer side of the needle withdrawing ring 82, the needle withdrawing rod 83 is connected with the needle withdrawing ring 82, the axis of the needle withdrawing rod 83 is parallel to the axis of the piston rod 221, and the needle withdrawing ring 82 can drive the suction head 11 to be gradually separated from the suction head mounting nozzle 13 when the guide block 42 is gradually close to and contacted with and pushes the needle withdrawing rod to move along the first direction; the needle withdrawal ring 82 is provided with a first limit rod 85 along a first direction for preventing excessive pressing of the suction head; the second limiting rod 87 and the compression spring 86 are arranged on the first sensing piece 56, and the compression spring 86 plays a role in buffering and is used for preventing abnormal sound from being generated when the precision pipette is rapidly moved up and down; the second stopper rod 87 is used for stopping the compression spring 86.

The above embodiments are only for illustrating the technical concept and features of the present utility model, and are intended to enable those skilled in the art to understand the content of the present utility model and to implement the same, but are not intended to limit the scope of the present utility model, and all equivalent changes or modifications made according to the spirit of the present utility model should be included in the scope of the present utility model.

Claims

1. A pipette, characterized by comprising

the guide assembly comprises a linear guide rod and a guide block, the guide block is provided with a connecting through hole, one end of the linear guide rod is penetrated in the connecting through hole and can move along a first direction relative to the guide block, the other end of the linear guide rod is connected with a stepping motor, the second end of the plunger structure is connected with the guide block,

2. A pipette as recited in claim 1 wherein said pipette further comprises a tip assembly for taking or discharging liquid, said tip assembly comprising a tip, a tip mounting nozzle and a tip mounting nozzle platen, said tip mounting nozzle being connected to one end of said piston cylinder and secured by said tip mounting nozzle platen, said tip being connected to said tip mounting nozzle.

3. The pipette of claim 2 further comprising a housing assembly, the housing assembly comprising a stationary housing having a first housing section and a second housing section in a first direction, the tip assembly being disposed on the first housing section and the drive assembly being disposed on the second housing section; the fixed shell is provided with openings which are convenient for installing and detaching other components of the liquid transfer device, and each opening is provided with a cover plate.

4. A pipette as set forth in claim 3, wherein the pipette further comprises a needle withdrawal assembly comprising a needle withdrawal bin, a needle withdrawal ring, a shaft sleeve and a needle withdrawal rod, wherein the needle withdrawal ring is sleeved on the suction head and in interference fit with the suction head through the shaft sleeve, the needle withdrawal bin is arranged on the outer side of the needle withdrawal ring, the needle withdrawal rod is connected with the needle withdrawal ring,

the plunger structure comprises a piston rod and a piston rod,

the axis of the needle withdrawing rod is parallel to the axis of the piston rod, and the needle withdrawing ring can drive the suction head to be gradually separated from the suction head mounting nozzle when the guide block is gradually close to, contacted with and pushes the needle withdrawing rod to move along the first direction.

5. The pipette of claim 4 further comprising a sensor assembly, wherein the sensor assembly comprises a sensor circuit board, a pressure sensor, a first photoelectric sensor, a second photoelectric sensor, a third photoelectric sensor, a first sensing piece and a second sensing piece, wherein the pressure sensor, the first photoelectric sensor, the second photoelectric sensor and the third photoelectric sensor are sequentially arranged on the sensor circuit board along a first direction, and the first sensing piece is connected with the needle withdrawing rod and can move along the first direction along with the movement of the needle withdrawing rod; the second sensing piece is connected with the guide block and can move along a first direction along with the movement of the guide block, and the pressure sensor is connected with the piston cylinder and used for monitoring the liquid pressure in the suction head to judge whether the liquid is sucked into the suction head or not and the liquid quantity in the suction head; the first photoelectric sensor is used for monitoring the position of the first sensing piece to judge whether the suction head is installed in place or not; the second photoelectric sensor and the third photoelectric sensor are used for monitoring the position of the second sensing piece to judge the working state of the stepping motor.

6. The pipette of claim 5 further comprising a wire insertion assembly, said wire insertion assembly comprising a first wire insertion assembly and a second wire insertion assembly, said first wire insertion assembly having one end connected to a sensor circuit board and the other end connected to a control mechanism or a power supply assembly; one end of the second plug wire assembly is connected with the stepping motor, and the other end of the second plug wire assembly is connected with the control mechanism or the power supply assembly.

7. A pipette as recited in claim 3 wherein said tip is provided with a first O-ring at the junction with said tip mounting nozzle, said first O-ring being disposed on said tip.

8. A pipette as defined in claim 3 wherein a second O-ring is provided at the junction of said tip mounting nozzle and the piston cylinder, said second O-ring being disposed over said tip mounting nozzle.

9. The pipette of claim 4 wherein said plunger structure further comprises a piston gland and a V-shaped seal, said piston gland being disposed over said piston rod and between said piston rod and said piston cylinder, said V-shaped seal being disposed over said piston rod and said piston gland.