CN218689609U

CN218689609U - Liquid transfer mechanism of automatic capacity switching liquid transfer pump

Info

Publication number: CN218689609U
Application number: CN202222907225.8U
Authority: CN
Inventors: 林志杰; 梁松伟; 刘睿; 何卉
Original assignee: Ruike Biochemical Technology Guangdong Co ltd
Current assignee: Ruike Biochemical Technology Guangdong Co ltd
Priority date: 2022-11-01
Filing date: 2022-11-01
Publication date: 2023-03-24
Anticipated expiration: 2032-11-01

Abstract

The utility model discloses a liquid-transfering mechanism of an automatic capacity-switching liquid-transfering pump, which comprises a cylinder seat, a large piston rod and a small piston rod, wherein the middle part of the cylinder seat is provided with a plurality of large piston cavities extending along the height direction of the cylinder seat, a large piston rod is respectively arranged in each large piston cavity, the large piston rod is in sealing fit with the large piston cavities to perform piston motion, and the middle part of the large piston rod is of a cavity structure; a small piston cavity is arranged below each large piston cavity of the cylinder block and communicated with the large piston cavity; a small piston rod is coaxially sleeved in a cavity of each large piston rod, the small piston rod is in sealing fit with the cavity of the large piston rod, and the small piston rod penetrates through the cavity to enter the small piston cavity and is in sealing fit with the small piston cavity to perform piston motion. The present case switches the range through the difference of the kinematic position of little piston rod and big piston rod in the cavity, makes the liquid-transfering pump satisfy the liquid-transfering needs of different ranges simultaneously, reduces the frequent change of liquid-transfering pump and liquid-transfering gun head, simplifies experiment operation flow, reduces the experiment cost.

Description

Liquid transfer mechanism of automatic capacity switching liquid transfer pump

Technical Field

The utility model relates to a move liquid pump technical field, in particular to move liquid mechanism of liquid pump.

Background

The liquid transfer pump is also called a liquid transfer gun, and is the most common tool for quantitatively transferring liquid in the field of biomedical science research at present. The prior commonly used liquid-transfering pump has various measuring range specifications of 100-1000ul, 20-200ul, 10-100ul, 2-20ul, 1-10ul, 0.1-1ul and the like. The liquid transfer pumps with different specifications can absorb and transfer liquid with accurate volume in the measuring range to other places by matching with the liquid transfer gun heads with different specifications.

The existing liquid transfer pump has the following defects:

1. the range is fixed, and the use is inconvenient:

the pipette gun with fixed range can not suck and transfer liquid with volume less than the minimum range or more than the maximum range, for example, a pipette pump with 100-1000ul range specification can not be used for transferring 50ul of liquid, otherwise, pipetting inaccuracy can be caused, and thus, an experimental result is greatly influenced. Therefore, a plurality of liquid-moving pumps are required to be prepared at the same time in the same experiment, and the liquid-moving pumps are switched back and forth in the experiment process, which is troublesome to operate.

2. The pipette head is frequently replaced, the consumption is large:

when the same kind of sample is sucked, the pipette tip has to be replaced when the pipette pump is replaced, which increases the cost of the pipette tip and the experiment cost.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an automatic switch capacity moves liquid mechanism that moves liquid pump can switch the range, realizes the ultramicro and moves the liquid, and compatible ordinary capacity moves the liquid requirement simultaneously to satisfy the demand of more liquid ranges that move, reduce the change of moving the liquid rifle head and consume, simplify experiment operation flow, reduce the experiment cost.

To achieve the above object, the solution of the present invention is: a liquid transfer mechanism of a liquid transfer pump capable of automatically switching capacity comprises a cylinder seat, a large piston rod and a small piston rod, wherein the middle part of the cylinder seat is provided with a plurality of large piston cavities extending along the height direction of the cylinder seat;

the cylinder block is provided with a small piston cavity below each large piston cavity, and the small piston cavity is communicated with the large piston cavity; and a small piston rod is coaxially sleeved in the cavity of each large piston rod, the small piston rod is in sealing fit with the cavity of the large piston rod, and the small piston rod penetrates through the cavity to enter the small piston cavity and is in sealing fit with the small piston cavity to perform piston motion.

Furthermore, a large piston driving mechanism is arranged on the large piston rod, and a small piston driving mechanism is arranged on the small piston rod.

Furthermore, a connecting cavity for communicating the large piston cavity with the small piston cavity is arranged below the large piston cavity, and the diameter of the cross section of the connecting cavity is smaller than that of the cross section of the large piston cavity.

Further, the top in little piston chamber is equipped with little piston rod guide holder, the inside cavity of little piston rod guide holder, the upper end of hollow portion radially outwards inclines and forms the inclined plane, little piston rod guide holder intercommunication little piston chamber and big piston chamber.

Further, the lower end of the small piston rod is close to the lower end face of the small piston cavity.

Furthermore, a first sealing ring is fixedly arranged in the small piston cavity, so that air sealing is formed between the small piston rod and the small piston cavity, and the upper end surface of the first sealing ring is a sealing surface of the small piston.

Furthermore, the periphery cover of big piston rod is equipped with the second sealing washer, and big piston rod lower terminal surface inlays and is equipped with the third sealing washer.

After the technical scheme is adopted, the beneficial effects of the utility model reside in that: a large piston cavity is arranged in a cylinder seat of the liquid transfer pump, a large piston rod is in sealing fit with the large piston cavity of the cylinder seat to perform piston motion, a communicated small piston cavity is arranged at the lower part of the large piston cavity, a small piston rod is coaxially sleeved in the hollow large piston rod, the small piston rod is in sealing fit with the small piston rod of the liquid transfer steel head to perform piston motion, and the liquid transfer pump absorbs liquid and sprays liquid to realize small-capacity liquid transfer; when the small piston moves upwards to exceed the small piston sealing surface of the small piston cavity, the large piston cavity is communicated with the small piston cavity, the large piston rod and the small piston rod move simultaneously, and the liquid is pumped by the liquid pump to suck liquid and spray liquid, so that large-capacity liquid transfer is realized. The present case is through the difference of the kinematic position of little piston rod and big piston rod in the cavity, controls and moves the liquid measure, switches the range to realize ultramicro and the liquid-transfering requirement of large capacity, make the liquid-transfering pump satisfy the liquid-transfering needs of different ranges simultaneously, reduce the frequent change of liquid-transfering pump and liquid-transfering gun head, simplify experiment operation flow, reduce the experiment cost.

Drawings

FIG. 1 is a sectional view of the liquid-displacing pump of the present invention;

FIG. 2 is a sectional view of the liquid transfer mechanism of the present invention;

FIG. 3 is a diagram of the working state of an embodiment of the present invention (small volume pipetting);

fig. 4 is a working state diagram (large capacity pipetting) of an embodiment of the present invention.

Description of reference numerals:

1. a pipetting mechanism; 2. a cylinder block; 21. a large piston chamber; 3. a large piston rod; 31. a cavity; 4. a small piston rod; 5. a liquid transfer steel head; 51. a small piston cavity; 52. a small piston sealing face; 6. a connecting cavity; 7. a small piston rod guide seat; 71. an annular step; 72. an inclined surface; 8. a third seal ring; 9. a fourth seal ring; 10. a small piston drive mechanism; 11. a large piston drive mechanism; 12. pipetting gun heads; 13. a first seal ring; 14. and a second seal ring.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The utility model provides an automatic switch over capacity liquid-transfering pump move liquid mechanism, as shown in fig. 1, move liquid mechanism 1 and include cylinder block 2, big piston rod 3,

little piston rod

4, 2 middle parts of cylinder block are equipped with the big piston chamber 21 that a plurality of extends along the direction of height, and a plurality of big piston chamber 21 parallel arrangement sets up, is equipped with a big piston rod 3 in every big piston chamber 21 respectively, and big piston rod 3 and big piston chamber 21 seal cooperation, and 3 middle parts of big piston rod are cavity 31 structure.

The cylinder block 2 is correspondingly provided with a small piston cavity 51 below each large piston cavity 21, in the embodiment, the small piston cavity 51 is arranged inside the liquid-transferring steel head 5, the upper part of the liquid-transferring steel head 5 is fixed in the cylinder block 2, and the lower part of the liquid-transferring steel head extends out of the bottom of the cylinder block 2 to be connected with an external liquid-transferring gun head 12. The small piston cavity 51 is communicated with the large piston cavity 21, the cavity 31 of each large piston rod 3 is coaxially sleeved with a small piston rod 4, the small piston rods 4 are in sealing fit with the cavities 31, the small piston rods 4 penetrate through the cavities 31 in the large piston rods 3 to enter the small piston cavities 51 in the pipetting steel heads 5, the small piston rods 4 are in sealing fit with the small piston cavities 51 to perform piston motion, the upper ends of the small piston cavities 51 form small piston sealing surfaces 52, and the upper parts of the small piston rods 4 are connected with the driving mechanism 8.

As shown in fig. 2 and 3, when the small piston rod 4 moves in the small piston cavity 51, the small piston cavity 51 and the large piston cavity 21 are in a blocked state, and when the small piston rod 4 moves upwards to exceed the small piston sealing surface 52 (i.e. the small piston rod 4 is completely separated from the small piston cavity 51), no air seal is formed between the small piston rod and the small piston cavity, so that the small piston cavity 51 is communicated with the large piston cavity 21.

In the embodiment, a connecting cavity 6 communicating the large piston cavity 21 and the small piston cavity 51 is arranged below the large piston cavity 21, the diameter of the cross section of the connecting cavity 6 is smaller than that of the large piston cavity 21, a step is formed at the joint of the large piston cavity 21 and the connecting cavity 6, and the large piston rod 3 is limited when moving to the step, so that the downward movement is stopped.

In order to facilitate accurate resetting of the small piston rod, a small piston rod guide seat 7 is arranged above the small piston cavity 51, the small piston rod guide seat 7 is hollow, the small piston rod guide seat 7 is communicated with the connecting cavity 6 so as to communicate the small piston cavity 51 with the large piston cavity 21, the upper portion of the small piston rod guide seat 7 is radially outwards protruded to form an annular step 71, and the annular step 71 abuts against the upper end face of the liquid-transferring steel head 5. In addition, the upper end of the hollow part of the small piston rod guide seat 7 is inclined radially outwards to form an inclined surface 72, and under the working condition of large capacity, the small piston rod 4 moves upwards to exceed the small piston sealing surface 52, namely, the small piston rod 4 is separated from the small piston cavity 51, and at the moment, the small piston rod guide seat 7 with the inclined surface 72 needs to be reset to enter the pipetting steel head 5 again.

The sealing elements are arranged at a plurality of positions to improve the air tightness of the device. A first sealing ring 13 is arranged between the small piston rod 4 and the small piston cavity 51, so that air sealing is formed between the small piston rod 4 and the small piston cavity 51, the first sealing ring 13 is fixedly arranged in the small piston cavity 51, the upper end surface of the first sealing ring 13 forms a small piston sealing surface 52 in the small piston cavity 51, and when the small piston rod 4 moves, the first sealing ring 13 does not move along with the small piston rod 4. The periphery cover of big piston rod 3 is equipped with second sealing washer 14, and second sealing washer 14 is used for sealed big piston rod 3 and big piston cavity 21, and third sealing washer 8 can be the high accuracy sealing washer, and different with the first sealing washer 13 of little piston rod 4 is, because third sealing washer 8 overlaps and establishes on big piston rod 3, so third sealing washer 8 follows big piston rod 3 and moves together in big piston cavity 21 to reach the effect that changes little piston cavity 51 and big piston cavity 21 internal pressure. In the low-volume working condition, the small piston rod 4 moves, but the total volume in the large piston cavity 21 is not changed, so the pressure of the large piston cavity is not changed, and other auxiliary mechanisms are not needed. In addition, a third sealing ring 8 is embedded in the lower end face of the large piston rod 3, the third sealing ring 8 can be a flange ring, and the third sealing ring 8 is used for sealing a gap between the small piston rod 4 and the cavity 31 of the large piston rod 3, so that air tightness is improved. The periphery cover of moving liquid steel head 5 is equipped with third sealing washer 9 to the reinforcing moves the gas tightness between liquid steel head 5 and the cylinder block 2.

Preferably, when liquid is sucked, the lower end part of the small piston rod 4 is closer to the target liquid, and the precision of the sucked liquid is higher, so that the proper length of the small piston rod 4 is set, the lower end part of the small piston rod 4 is enabled to be maximally close to the lower end surface of the liquid transfer steel head 5, namely maximally close to the target liquid without contacting the target liquid, the liquid suction high precision can be guaranteed, meanwhile, the small piston rod 4 is prevented from being polluted by the liquid, the use rate of the liquid transfer pump is reduced, and the service life of the liquid transfer pump is shortened.

In the present case, the large piston rod 3 and the small piston rod 4 are driven by a large piston drive mechanism 11 and a small piston drive mechanism 10, respectively. The large piston driving mechanism 11 is arranged above the large piston rod 3, and the large piston driving mechanism 11 works to drive the large piston rod 3 to do linear motion so as to change the air pressure in the large piston cavity 21; similarly, the small piston driving mechanism 10 is disposed above the small piston rod 4, and the small piston driving mechanism 10 operates to drive the small piston rod 4 to move linearly so as to change the air pressure in the small piston cavity 51.

The working principle is as follows:

1. ultramicro imbibition (50 nanoliter-10 microliter)

As shown in fig. 3, firstly, the pipette tip 12 is taken by the pipette pump, the pipette tip 12 is sleeved on the pipette steel head 5, then the small piston rod 4 driving component drives the small piston rod 4 to move upwards, negative pressure is formed in the small piston cavity 51, the liquid level at the pipette tip 12 rises to realize liquid suction, the whole body moves to a proper position after the liquid is taken by the pipette pump, the small piston driving mechanism 10 drives the small piston rod 4 to move downwards, positive pressure is formed in the small piston cavity 51, and the liquid is ejected, namely, the small-capacity pipette is realized.

2. High capacity imbibition (1-200 microliter)

As shown in fig. 4, firstly, the pipette tip 12 is taken by a pipette pump, the pipette tip 12 is sleeved on the pipette steel head 5, then the small piston rod 4 driving component drives the small piston rod 4 to move upwards, the small piston rod 4 does not move over the small piston sealing surface 52, the small piston cavity 51 is not communicated with the large piston cavity 21, when the small piston rod 4 moves over the small piston sealing surface 52, at this time, the small piston cavity 51 is communicated with the large piston cavity 21, then, the large piston driving mechanism 11 and the small piston driving mechanism 10 drive the large piston rod 3 and the small piston rod 4 to move upwards respectively, negative pressure is formed in the communicated small piston cavity 51 and the large piston cavity 21, the liquid level of the pipette tip 12 rises to achieve liquid suction, after the liquid is sucked by the pipette pump, the whole body moves to a proper position, the large piston rod 3 moves downwards, the small piston rod 4 does not move, the small piston cavity 51 and the large piston cavity 21 are kept communicated and form positive pressure, and liquid is ejected, namely, and large-capacity liquid transfer is achieved.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the design of the present application, and all equivalent changes made according to the design key of the present application fall within the protection scope of the present application.

Claims

1. The utility model provides an automatic switch over capacity liquid-transfering pump move liquid mechanism which characterized in that: the piston comprises a cylinder seat, a large piston rod and a small piston rod, wherein the middle part of the cylinder seat is provided with a plurality of large piston cavities extending along the height direction of the cylinder seat, each large piston cavity is internally provided with the large piston rod, the large piston rod and the large piston cavity are in sealing fit for piston motion, and the middle part of the large piston rod is of a cavity structure;

2. A pipetting mechanism as recited in claim 1 wherein the pipetting mechanism comprises: the large piston rod is provided with a large piston driving mechanism, and the small piston rod is provided with a small piston driving mechanism.

3. A pipetting mechanism as recited in claim 1 wherein the pipetting mechanism comprises: and a connecting cavity communicated with the large piston cavity and the small piston cavity is arranged below the large piston cavity, and the diameter of the cross section of the connecting cavity is smaller than that of the cross section of the large piston cavity.

4. A pipetting mechanism for an automatic switched volume pipetting pump as recited in claim 1 wherein: the top in little piston chamber is equipped with little piston rod guide holder, the inside cavity of little piston rod guide holder, the upper end of hollow portion radially leans out and forms the inclined plane, little piston rod guide holder intercommunication little piston chamber and big piston chamber.

5. A pipetting mechanism for an automatic switched volume pipetting pump as recited in claim 1 wherein: the lower end of the small piston rod is close to the lower end face of the small piston cavity.

6. A pipetting mechanism for an automatic switched volume pipetting pump as recited in claim 1 wherein: a first sealing ring is fixedly arranged in the small piston cavity, so that air sealing is formed between the small piston rod and the small piston cavity, and the upper end face of the first sealing ring is a small piston sealing face.

7. A pipetting mechanism for an automatic switched volume pipetting pump as recited in claim 1 wherein: the periphery cover of big piston rod is equipped with the second sealing washer, and big piston rod lower terminal surface inlays and is equipped with the third sealing washer.