Multi-channel flexible piston sleeve pipette

Abstract

The utility model discloses a multichannel flexible piston sleeve pipette which comprises a shell, a driving mechanism, a plurality of pistons, a sleeve assembly and a coaxiality self-adaptive fine adjustment mechanism, the sleeve assembly is fixed to the shell and comprises a plurality of channels. The first end of the piston is in transmission connection with the driving mechanism through the coaxiality self-adaptive fine adjustment mechanism; the second ends of the pistons are inserted into the sleeve assembly from the first ends of the channels in a one-to-one correspondence mode. According to the multi-channel flexible piston sleeve pipette disclosed by the utility model, the installation difficulty of the piston can be greatly reduced, the connection precision requirement between the piston and the driving mechanism is reduced, and the coaxiality of the piston and the sleeve assembly can be ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid transfer guns, and in particular relates to a multi-channel flexible piston sleeve liquid transfer gun. Background Art

[0002] See also Figure 1 At present, the working principle of the pipettes on the market is based on the air displacement method, and the liquid is sucked in and discharged through the displaced air. Each pipette has an internal piston 2 connected to the sleeve 1, and the volume of air directly pushed out by the piston 2 is equal to the volume of liquid sucked in. The factors that affect the performance of the pipette are mainly: 1. The relative sealing between the piston 2 and the sleeve 1; 2. The concentricity between the piston 2 and the sleeve 1 parts (parts tolerance). The better the concentricity, the more repeated movement of the piston 2, and the more stable the volume of air pushed out, that is, the better the stability of the pipette; 3. The dead volume between the piston 2 and the sleeve 1. The smaller the dead volume, the better. The dead volume refers to the volume of the gap between the piston 2 and the sleeve 1.

[0003] The structure of an existing multi-channel pipette generally includes a driving mechanism 3, multiple pistons 2 and multiple sleeves 1. The pistons 2 are inserted into the sleeves 1 one by one and are transmission-connected to the driving mechanism 3. The pistons 2 and the driving mechanism 3 are rigidly connected. The concentricity of the pistons 2 and the sleeves 1 depends entirely on the processing quality and assembly quality of the parts, thereby placing high requirements on the processing and assembly of the parts.

[0004] In addition, the existing sleeve 1 is an integrated solution, and is connected to the pneumatic adapter through a welded adapter. Welding can easily cause deformation of the sleeve. The diameter of the sleeve 1 is generally around 5 or 6 mm. Welding on such a small component must ensure that it does not deform, which makes the solution very demanding on the production and processing of parts. The one-piece sleeve 1 is usually relatively long, and it is difficult to ensure its concentricity during installation. At the same time, when liquid is sucked into the sleeve 1 by misoperation, or when part of the sleeve 1 is damaged, the entire sleeve 1 needs to be replaced, and the replacement and maintenance costs are high. Summary of the invention

[0005] In view of the deficiencies in the above-mentioned prior art, the utility model aims to provide a multi-channel flexible piston-sleeve pipette, which can greatly reduce the difficulty of installing the piston, reduce the connection accuracy requirements between the piston and the drive mechanism, and ensure the coaxiality of the piston and sleeve assembly.

[0006] In order to achieve the above-mentioned purpose, the utility model provides a multi-channel flexible piston sleeve pipette, comprising a shell, a driving mechanism, multiple pistons, a sleeve assembly and a coaxiality adaptive fine-tuning mechanism; the sleeve assembly is fixed to the shell and comprises multiple channels; the first end of the piston is transmission-connected to the driving mechanism through the coaxiality adaptive fine-tuning mechanism; the second end of the piston is inserted into the sleeve assembly from the first end of the channel one by one.

[0007] As an embodiment, the coaxiality adaptive fine-tuning mechanism includes a driving block, multiple end plates, multiple elastic members and multiple guide structures; the driving block is transmission-connected to the driving mechanism and forms multiple columnar spaces in parallel inside, and a through hole is formed at one end of the columnar space; the first end of the piston forms a hemispherical arc surface and extends from the through hole into the corresponding columnar space in a one-to-one correspondence with the columnar space; the end plate is fixed to the periphery of the first end of the piston; the elastic member is pressed between the end plate and the inner wall of the driving block on the side adjacent to the through hole; the elastic member presses the first end of the piston tightly against the inner wall of the driving block away from the through hole through the end plate; the guide structure is arranged in the channel, and the guide structure guides the piston.

[0008] As an implementation manner, the elastic member is a spring.

[0009] As an embodiment, the guide structure adopts a sleeve; the first end of the channel is recessed to form a sleeve mounting groove; the sleeve is fixed in the sleeve mounting groove; the inner diameter of the sleeve matches the outer diameter of the piston; and the sleeve is coaxially arranged with the channel; the piston is inserted in the sleeve and the channel.

[0010] As an embodiment, the sleeve assembly includes a plurality of first sleeves; each of the first sleeves forms a channel.

[0011] As an embodiment, the sleeve assembly includes multiple first sleeves and a second sleeve; each of the first sleeves forms a first channel; the second sleeve forms a plurality of parallel second channels; the first sleeve and the second sleeve cooperate with each other, the first end of the first channel is coaxially sealed and connected with the second end of the second channel one by one; and the inner diameter of the first channel cooperates with the inner diameter of the second channel; the first channel and the second channel cooperate to form the channel.

[0012] As an implementation manner, the end portion of the second end of the second channel is recessed to form a first sleeve installation groove; the first end of the first sleeve is inserted into the first sleeve installation groove.

[0013] As an embodiment, the first end of the first sleeve and the outer wall depression corresponding to the first sleeve installation groove form a sealing ring installation groove, and a sealing ring is installed in the sealing ring installation groove; the first sleeve and the second sleeve are sealed together through the sealing ring.

[0014] As an implementation manner, the first sleeve is detachably connected to the housing or the second sleeve.

[0015] As an implementation manner, the second sleeve is also integrally formed with a plurality of air pressure adapters; the air pressure adapters are connected to the second channels one by one.

[0016] The utility model adopts the above technical solution, so that it has the following beneficial effects:

[0017] The adoption of the coaxiality adaptive fine-tuning mechanism in the utility model ensures that there is only axial limitation between the piston and the drive block, and flexibility exists in other directions; it can greatly reduce the coaxiality requirements of the processing piston and sleeve assembly, reduce the connection accuracy requirements between the piston and the drive mechanism, and ensure the coaxiality of the piston and the first sleeve and the second sleeve. The guide structure is used to limit the axial direction of the piston, ensure the concentricity of the piston and the first sleeve and the second sleeve, and ensure that the distance of the piston movement in each channel is consistent, thereby improving the uniformity of the pipetting of each channel. The elastic member is used to ensure that the first end of the piston is pressed tightly against the inner wall of the drive block away from the through hole, thereby ensuring the uniformity of the pipetting of each channel. When the sleeve assembly adopts a split structure of a first sleeve and a second sleeve, firstly, the difficulty of machining the coaxiality of the first sleeve and the second sleeve is reduced; secondly, when the split first sleeve and the second sleeve cause liquid to be sucked into the first sleeve due to an erroneous operation, or when the first sleeve is partially damaged, only the first sleeve needs to be replaced, thereby greatly reducing the maintenance cost; in addition, the second sleeve is integrally formed to form a pneumatic adapter, thereby eliminating the problems of high difficulty in welding the existing pneumatic adapter and easy deformation of the sleeve, thereby reducing the difficulty of machining the pneumatic adapter, while also ensuring the stability of the sleeve structure and reducing the loss cost in the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a stereogram of an existing pipette;

[0020] Figure 2It is a cross-sectional view of an existing pipette;

[0021] Figure 3 This is a schematic diagram of the connection structure between the sleeve assembly and the drive mechanism of the multi-channel flexible piston sleeve pipette of an embodiment of the present application;

[0022] Figure 4 This is a cross-sectional view of the connection structure between the sleeve assembly and the drive mechanism of the multi-channel flexible piston sleeve pipette of an embodiment of the present application;

[0023] Figure 5 for Figure 4 A partial enlarged view of the middle A area;

[0024] Figure 6 for Figure 4 A partial enlarged view of area B in the middle.

[0025] Description of Figure Numbers:

[0026] Figure 1-2 :

[0027] 1- sleeve;

[0028] 2-Piston;

[0029] 3- Driving mechanism.

[0030] Figure 3 to Figure 6 :

[0031] 1- driving mechanism;

[0032] 2-Piston;

[0033] 3-sleeve assembly;

[0034] 31- first sleeve;

[0035] 311- nozzle connection part; 312- sealing ring installation groove; 313- first channel;

[0036] 32- second sleeve;

[0037] 321-first sleeve mounting groove; 322-second channel;

[0038] 4-Coaxiality adaptive fine-tuning mechanism;

[0039] 41-driving block; 42-end piece; 43-elastic member; 44-shaft sleeve; 45-sealing structure;

[0040] 5-sleeve mounting groove;

[0041] 6- Sealing ring. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0043] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "center", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc., are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "setting", "connection", "connection" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Example 1

[0046] See also Figure 3 to Figure 6 A multi-channel flexible piston sleeve pipette gun according to a first embodiment of the utility model comprises a shell, a driving mechanism 1, a plurality of pistons 2, a sleeve assembly 3 and a coaxiality adaptive fine-tuning mechanism 4; the sleeve assembly 3 is fixed to the shell and comprises a plurality of channels; the first end of the piston 2 is transmission-connected to the driving mechanism 1 through the coaxiality adaptive fine-tuning mechanism 4; the second end of the piston 2 is inserted into the sleeve assembly 3 from the first end of the channel in a one-to-one correspondence.

[0047] The adoption of the coaxiality adaptive fine-tuning mechanism 4 ensures that there is only axial limitation between the piston 2 and the drive mechanism 1, and flexibility is present in other directions; different from the existing rigid connection structure, it can greatly reduce the difficulty of installing the piston 2, reduce the connection accuracy requirements between the piston 2 and the drive mechanism 1, and ensure the coaxiality of the piston 2 and the sleeve assembly 3.

[0048] The driving mechanism 1 is used to drive the piston 2 to reciprocate along the axial direction through the coaxiality adaptive fine-tuning mechanism 4 to achieve the operation of pipetting.

[0049] As an embodiment, the sleeve assembly 3 includes multiple first sleeves 31 and a second sleeve 32; each of the first sleeves 31 forms a first channel 313; the second sleeve 32 forms a plurality of parallel second channels 322; the first sleeve 31 and the second sleeve 32 cooperate with each other, and the first end of the first channel 313 corresponds to the second end of the second channel 322 in a coaxial sealed manner; and the inner diameter of the first channel 313 cooperates with the inner diameter of the second channel 322; the first channel 313 and the second channel 322 cooperate to form the channel.

[0050] In the utility model, the one-piece sleeve is replaced with a split first sleeve 31 and a second sleeve 32. Firstly, the length of a single sleeve is shortened, thereby reducing the difficulty of coaxiality processing of the first sleeve 31 and the second sleeve 32. Secondly, when the split first sleeve 31 and the second sleeve 32 are operated incorrectly and liquid is sucked into the first sleeve 31, or when part of the first sleeve 31 is damaged, only the first sleeve 31 needs to be replaced, thereby greatly reducing maintenance costs.

[0051] As an embodiment, the coaxiality adaptive fine-tuning mechanism 4 includes a driving block 41, multiple end plates 42, multiple elastic members 43 and multiple guide structures; the driving block 41 is transmission-connected to the driving mechanism 1 and forms multiple columnar spaces in parallel inside, and a through hole is formed at one end of the columnar space; the first end of the piston 2 forms a hemispherical arc surface and extends from the through hole into the corresponding columnar space in a one-to-one correspondence with the columnar space; the end plate 42 is fixed to the periphery of the first end of the piston 2; the elastic member 43 is pressed between the end plate 42 and the inner wall of the driving block 41 adjacent to the through hole; the elastic member 43 presses the first end of the piston 2 tightly against the inner wall of the driving block 41 away from the through hole through the end plate 42; the guide structure is arranged in the channel, and the guide structure guides the piston 2.

[0052] The elastic force of the elastic member 43 must ensure that during use, the first end of the piston 2 is pressed tightly against the inner wall of the driving block 41 away from the through hole, so as to ensure the stability of the pipetting amount during use, thereby ensuring the uniformity of pipetting in each channel.

[0053] The guide structure is used to limit the axial position of the piston 2, ensure the concentricity of the piston 2 and the first sleeve 31 and the second sleeve 32, and ensure that the movement distance of the piston 2 in each channel is consistent, thereby improving the uniformity of pipetting in each channel.

[0054] In this embodiment, the driving mechanism 1 includes a motor and a driving screw. The motor is transmission-connected to the driving screw, and the driving screw is connected to the driving block 41 .

[0055] As an implementation manner, the elastic member 43 is a spring. In other embodiments, the elastic member 43 may also be other elastic parts.

[0056] As an embodiment, the guide structure adopts a sleeve 44; the first end of the channel is recessed to form a sleeve mounting groove 5; the sleeve 44 is fixed in the sleeve mounting groove 5; the inner diameter of the sleeve 44 matches the outer diameter of the piston 2; and the sleeve 44 is coaxially arranged with the channel; the piston 2 is inserted in the sleeve 44 and the channel.

[0057] As an implementation manner, the end portion of the second end of the second channel 322 is recessed to form a first sleeve installation groove 321 ; the first end of the first sleeve 31 is inserted into the first sleeve installation groove 321 .

[0058] The first sleeve installation groove 321 provides space for installing the first end of the first sleeve 31 , and provides a basis for ensuring that the inner diameters of the first channel 313 and the second channel 322 match and for the first channel 313 and the second channel 322 to be coaxially connected.

[0059] As an embodiment, the first end of the first sleeve 31 and the outer wall depression corresponding to the first sleeve installation groove 321 form a sealing ring installation groove 312, and a sealing ring 6 is installed in the sealing ring installation groove 312; the first sleeve 31 and the second sleeve 32 are sealed together through the sealing ring 6.

[0060] The use of the sealing ring 6 ensures the sealing fit between the first sleeve 31 and the second sleeve 32 .

[0061] As an implementation manner, the first sleeve 31 is detachably connected to the housing or the second sleeve 32 .

[0062] The first sleeve 31 is detachably connected to the shell or the second sleeve 32, so that when liquid is sucked into the first sleeve 31 due to an erroneous operation, or when the first sleeve 31 is partially damaged, the first sleeve 31 can be easily replaced.

[0063] As an implementation manner, the second end of the first sleeve 31 forms a nozzle connecting portion 311 .

[0064] The nozzle connection portion 311 is used to connect a disposable nozzle when the pipette is actually used.

[0065] Example 2

[0066] The multi-channel flexible piston sleeve pipette gun of the second embodiment of the utility model has a structure basically the same as that of the first embodiment, except that the sleeve assembly 3 includes a plurality of first sleeves 31, but no second sleeve 32 is provided; each of the first sleeves 31 forms a channel.

[0067] Although the sleeve assembly 3 at this time does not have the advantages of the split sleeve in the present embodiment, due to the provision of a coaxiality adaptive fine-tuning mechanism 4, there is only axial limitation between the piston 2 and the drive mechanism 1, and flexibility is present in other directions; different from the existing rigid connection structure, the installation difficulty of the piston 2 can be greatly reduced, the connection accuracy requirements between the piston 2 and the drive mechanism 1 are reduced, and the coaxiality of the piston 2 and the first sleeve 31 can be ensured.

[0068] Example 3

[0069] A multi-channel flexible piston sleeve pipette gun according to the third embodiment of the utility model has a structure that is basically the same as that of the first embodiment, except that the second sleeve 32 is also integrally formed with a plurality of pneumatic adapters; the pneumatic adapters are connected to the second channels 322 one by one.

[0070] The second sleeve 32 is integrally formed to form a pneumatic adapter, and machining is used instead of welding, thereby eliminating the problems of high difficulty in welding the existing pneumatic adapter and easy deformation of the sleeve, reducing the difficulty in processing the pneumatic adapter, while also ensuring the stability of the sleeve structure, facilitating the guarantee of part size, and reducing loss costs during the production process.

[0071] As an implementation manner, the air pressure adapters are respectively connected to an air pressure sensor.

[0072] The air pressure sensor is used to monitor the air pressure intensity in the second sleeve 32 through the air pressure adapter.

[0073] Example 4

[0074] A multi-channel flexible piston sleeve pipette gun according to embodiment 4 of the utility model has a structure that is basically the same as that of embodiment 1, with the difference that the sleeve assembly 3 includes a plurality of first sleeves 31 and a plurality of second sleeves 32; each of the first sleeves 31 forms a first channel 313; each of the second sleeves 32 forms a second channel 322; the first sleeves 31 and the second sleeves 32 cooperate with each other, and the first end of the first channel 313 is coaxially sealed and connected with the second end of the second channel 322 in a one-to-one correspondence.

[0075] In other embodiments, the structure of the sleeve assembly 3 may also be adjusted accordingly according to actual needs, but multiple channels need to be formed.

[0076] Example 5

[0077] A multi-channel flexible piston sleeve pipette gun according to embodiment 5 of the utility model has a structure that is basically the same as that of embodiment 1, with the difference that the guide structure includes a plurality of arc-shaped tube segments; the first end of the second sleeve 32 is recessed at intervals along the circumferential direction to form a plurality of guide member mounting grooves; the arc-shaped tube segments are fixed in the guide member mounting grooves; the inner diameter of the arc-shaped tube segments matches the outer diameter of the piston 2; and the arc-shaped tube segments are all coaxially arranged with the second sleeve 32; the piston 2 is inserted between each of the arc-shaped tube segments and in the second sleeve 32.

[0078] The structure of the guide structure is not limited to the sleeve 44 and the pipe sheet. In other embodiments, other structures that can ensure the concentricity of the piston 2 and the first sleeve 31 and the second sleeve 32 can also be used.

[0079] Example 6

[0080] The structure of the multi-channel flexible piston sleeve pipette gun of the sixth embodiment of the present invention is basically the same as that of the first embodiment, except that a sealing structure 45 is provided beside the guide structure 44 at the first end of the second channel 322. The sealing structure 45 can be an existing sealing member such as a sealing ring.

[0081] The use of the sealing structure 45 ensures the sealing between the piston 2 and the second sleeve 32 .

[0082] The utility model is described in detail above in conjunction with the embodiments of the drawings. A person skilled in the art can make various variations of the utility model according to the above description. Therefore, some details in the embodiments should not constitute a limitation of the utility model, and the scope of protection of the utility model shall be defined by the scope of the attached claims.

Claims

1. A multi-channel flexible piston sleeve pipette, characterized in that: It includes a shell, a driving mechanism, multiple pistons, a sleeve assembly and a coaxiality adaptive fine-tuning mechanism; the sleeve assembly is fixed to the shell and includes multiple channels; the first end of the piston is transmission-connected to the driving mechanism through the coaxiality adaptive fine-tuning mechanism; the second end of the piston is inserted into the sleeve assembly from the first end of the channel in a one-to-one correspondence.

2. The multi-channel flexible piston sleeve pipette according to claim 1, characterized in that: The coaxiality adaptive fine-tuning mechanism includes a driving block, multiple end plates, multiple elastic members and multiple guide structures; the driving block is transmission-connected to the driving mechanism and forms multiple columnar spaces in parallel inside, and a through hole is formed at one end of the columnar space; the first end of the piston forms a hemispherical arc surface and extends from the through hole into the corresponding columnar space in a one-to-one correspondence with the columnar space; the end plate is fixed to the periphery of the first end of the piston; the elastic member is pressed between the end plate and the inner wall of the driving block on the side adjacent to the through hole; the elastic member presses the first end of the piston tightly against the inner wall of the driving block on the side away from the through hole through the end plate; the guide structure is arranged in the channel, and the guide structure guides the piston.

3. The multi-channel flexible piston sleeve pipette according to claim 2, characterized in that: The elastic member is a spring.

4. The multi-channel flexible piston sleeve pipette according to claim 2, characterized in that: The guide structure adopts a sleeve; the first end of the channel is recessed to form a sleeve installation groove; the sleeve is fixed in the sleeve installation groove; the inner diameter of the sleeve matches the outer diameter of the piston; and the sleeve is coaxially arranged with the channel; the piston is inserted in the sleeve and the channel.

5. The multi-channel flexible piston sleeve pipette according to any one of claims 1 to 4, characterized in that: The sleeve assembly includes a plurality of first sleeves; each of the first sleeves forms a channel.

6. The multi-channel flexible piston sleeve pipette according to any one of claims 1 to 4, characterized in that: The sleeve assembly includes multiple first sleeves and a second sleeve; each of the first sleeves forms a first channel; the second sleeve forms multiple parallel second channels; the first sleeve and the second sleeve cooperate with each other, the first end of the first channel is coaxially sealed and connected with the second end of the second channel one by one; and the inner diameter of the first channel cooperates with the inner diameter of the second channel; the first channel and the second channel cooperate to form the channel.

7. The multi-channel flexible piston sleeve pipette according to claim 6, characterized in that: The end portion of the second end of the second channel is recessed to form a first sleeve installation groove; the first end of the first sleeve is inserted into the first sleeve installation groove.

8. The multi-channel flexible piston sleeve pipette according to claim 7, characterized in that: The first end of the first sleeve and the outer wall corresponding to the first sleeve installation groove are recessed to form a sealing ring installation groove, and a sealing ring is installed in the sealing ring installation groove; the first sleeve and the second sleeve are sealed and matched through the sealing ring.

9. The multi-channel flexible piston sleeve pipette according to claim 6, characterized in that: The first sleeve is detachably connected to the housing or the second sleeve.

10. The multi-channel flexible piston sleeve pipette according to claim 6, characterized in that: The second sleeve is also integrally formed with a plurality of air pressure adapters; the air pressure adapters are connected to the second channels one by one.

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