Miniature plunger pump for pipetting

Abstract

The invention discloses a miniature plunger pump for pipetting. The miniature plunger pump comprises a pump main body, a first detection device, a driving device and a second detection device, the pump main body comprises a cavity, a pushing assembly and an adaptive plug in which a TIP head can be inserted, the pushing assembly comprises a pushing block and a pushing rod connected to the bottom of the pushing block, the pushing rod is sleeved with a spring, the top of the cavity is downwards concavely provided with a first groove, the pushing block is movably arranged in the first groove, and the top of the pushing block exceeds the first groove; the first detection device is used for detecting whether a TIP head is inserted into the push block; the driving device comprises a support, a motor, a plunger assembly and a guide assembly, the guide assembly comprises a vertical guide groove and a guide column, one of the vertical guide groove and the guide column is arranged on the periphery of the plunger connector, and the other one of the vertical guide groove and the guide column is arranged on the support; and the second detection device is used for identifying the operation position of the micro plunger pump. The miniature plunger pump is smaller in overall size, the internal space of the plunger pump is reasonably utilized, and the structural design is ingenious.

Description

Technical Field

[0001] The invention relates to the field of pipette technology, in particular to a micro plunger pump used for pipetting. Background Art

[0002] Pipettes are very mature in the current market and can meet very high precision requirements. However, traditional pipettes use expensive slide rails as guide mechanisms, which are expensive. In addition, most pipettes are driven by screw motors, so the overall length of the appearance is relatively long.

[0003] In order to reduce costs, compared with traditional pipettes, we found that plunger pumps and pipettes have the same working principle, but the cost of plunger pumps is generally lower than that of pipettes. Micro plunger pumps have been widely used in medicine, biology, chemistry and other fields. Their working principle is to drive the motor to make the plunger reciprocate in the cavity through the transmission mechanism, compressing and expanding the air in the cavity, thereby realizing the instrument's discharge and aspiration functions. In the current market, the main disadvantages of micro plunger pumps are: 1. The overall structure is not small and convenient enough; 2. The plunger pump does not have a direct TIP head; 3. The cost is relatively high when the TIP is used for direct pipetting.

[0004] Therefore, how to miniaturize the volume and reduce the production cost has become a key research direction in the industry, and it is necessary to design a new technical solution to solve the above problems. Summary of the invention

[0005] In view of this, the present invention aims at the deficiencies in the prior art, and its main purpose is to provide a micro plunger pump for pipetting, which is provided with a first groove, and the push block can be retracted into the first groove, so that the overall volume of the micro plunger pump is smaller, and the motor can drive the plunger connector to press the anti-detachment part upward, so that the push block can automatically push the TIP head away from the adapter plug under the elastic force of the spring, thereby realizing automatic disassembly of the TIP head. At the same time, the setting of the spring can ensure that after the TIP head is removed from the adapter plug, the adapter plug will not shake at will to produce abnormal noise. In conjunction with the setting of the first detection device and the second detection device, after the plunger connector runs to the top, the first detection device can be used to further ensure whether the TIP head is inserted into the adapter plug, and the screw rod, the plunger connector, and the plunger rod are arranged together in the channel, which reasonably utilizes the internal space of the plunger pump, and uses the guide structure of the guide column and the vertical guide groove. Compared with the slide rail structure, the production cost of the plunger pump can be further reduced, and the structural design is ingenious.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions: A micro plunger pump for pipetting, comprising: The pump body comprises a cavity, a pushing assembly and an adapter plug for inserting a TIP head, the pushing assembly comprises a pushing block and a pushing rod connected to the bottom of the pushing block, the pushing rod outer sleeve is provided with a spring, the top of the cavity is downwardly concavely provided with a first groove, the pushing block is movably arranged in the first groove and the top of the pushing block exceeds the first groove, the bottom wall of the first groove is downwardly provided with a through hole penetrating the cavity, the bottom of the pushing rod passes through the through hole and is provided with an anti-slip portion, the top of the through hole is provided with an abutting groove, the two ends of the spring respectively abut against the bottom of the pushing block and the bottom of the abutting groove, the bottom of the cavity is upwardly provided with a accommodating cavity for sliding connection of the plunger rod and communicating with the first groove, the bottom of the adapter plug is connected to the top of the accommodating cavity, and the top of the adapter plug passes through the pushing block upward and protrudes from the top of the pushing block; A first detection device, the first detection device is used to detect whether a TIP head is inserted on the push block, the first detection device comprises a first optical coupler arranged on the cavity and a first baffle connected to the bottom of the push block, and a first avoidance groove for the first baffle to move away is provided at the bottom of the first groove; A driving device, the driving device includes a bracket, a motor, a plunger assembly and a guide assembly, the bracket is connected to the bottom of the pump body, the bracket is provided with a channel running through from top to bottom, the motor is arranged at the bottom of the bracket, the top of the motor is connected with a screw rod extending into the channel, the plunger assembly includes a plunger rod and a plunger connector connected to the bottom of the plunger rod, the top of the plunger rod is slidably connected to the accommodating cavity, the bottom of the plunger connector is provided with a second avoidance groove upwards, the bottom end of the second avoidance groove is provided with a threaded connection part threadedly connected to the screw rod, the guide assembly includes a vertical guide groove and a guide column matching the vertical guide groove, one of the vertical guide groove and the guide column is arranged on the outer periphery of the plunger connector, and the other is arranged on the bracket, and the motor can drive the plunger connector to press upward against the anti-slip part; The second detection device is used to identify the operating position of the micro plunger pump. The second detection device includes a second optical coupler arranged on the bracket and a second baffle connected to the outer periphery of the plunger connector. The channel is provided with a third avoidance groove for the second baffle to move around.

[0007] As a preferred solution, the push block includes a push rod connecting portion and a sleeve portion extending upward from the top of the push rod connecting portion, and the top of the adapter plug protrudes from the top of the sleeve portion.

[0008] As a preferred solution, a second groove is recessed upwardly at the bottom of the push rod connecting part, and correspondingly, a boss matching the second groove is convexly provided on the bottom wall of the first groove, and the boss is located at the outer periphery of the top end of the accommodating cavity.

[0009] As a preferred solution, two of the spring, the through hole and the push rod are provided, and the two push rods are provided on opposite sides of the push block.

[0010] As a preferred solution, a mounting portion is convexly provided on the bottom of the adapter plug, and the mounting portion is interference fit with the top of the accommodating cavity. A first sealing ring is sandwiched between the bottom of the adapter plug and the cavity, and the first sealing ring is located on the outer periphery of the mounting portion.

[0011] As a preferred solution, the cavity is provided with a plurality of empty slots for reducing weight.

[0012] As a preferred solution, a mounting plate is provided at the bottom of the cavity, and the bracket is fixed to the bottom of the cavity through the mounting plate.

[0013] As a preferred solution, a seal installation groove is opened at the bottom of the cavity on the outer periphery of the accommodating cavity, a seal installed on the outer periphery of the plunger rod is arranged in the seal installation groove, and the mounting plate fixes the seal in the seal installation groove.

[0014] As a preferred embodiment, a third groove is provided downwardly at the top of the bracket on the outer periphery of the channel, the bottom of the anti-slip portion can partially abut against the bottom wall of the third groove, and a fourth groove is provided upwardly at the bottom of the mounting plate, and the top of the anti-slip portion is limited by the top wall of the fourth groove.

[0015] As a preferred solution, the motor has a rotating rod, and the screw rod is interference fit with the outer circumference of the rotating rod and is fixed by glue dispensing.

[0016] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solution that: Mainly, by providing a first groove, the push block can be retracted into the first groove, so that the overall volume of the micro plunger pump is smaller, and the motor can drive the plunger connector to press the anti-detachment part upward, so that the push block can automatically push the TIP head away from the adapter plug under the elastic force of the spring, thereby realizing automatic disassembly of the TIP head. At the same time, the setting of the spring can ensure that after the TIP head is removed from the adapter plug, the adapter plug will not shake at will and produce abnormal noise. In conjunction with the setting of the first detection device and the second detection device, after the plunger connector runs to the top, the first detection device can be used to further ensure whether the TIP head is inserted into the adapter plug, and the screw rod, the plunger connector, and the plunger rod are arranged together in the channel, which reasonably utilizes the internal space of the plunger pump, and uses the guide structure of the guide column and the vertical guide groove. Compared with the slide rail structure, the production cost of the plunger pump can be further reduced, and the structural design is ingenious.

[0017] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional schematic diagram of a preferred embodiment 1 of the present invention; Figure 2 It is an exploded view of a preferred embodiment 1 of the present invention; Figure 3 It is a cross-sectional schematic diagram of a preferred embodiment 1 of the present invention; Figure 4 is another cross-sectional schematic diagram of a preferred embodiment 1 of the present invention; Figure 5 It is a cross-sectional schematic diagram of a preferred embodiment 2 of the present invention.

[0019] Description of the accompanying drawings: 10. Pump body 11. Cavity 111, first groove 112, via hole 113, abutment groove 114, accommodating cavity 115. Seal installation groove 116. Boss 117. First avoidance groove 12. Pushing component 121. Push block 122. Push rod 123. Spring 124. Anti-slip part 125. Push rod connection part 126. Sleeve part 127. Second groove 13. Adapter plug 131, mounting portion 20, first detection device 21. First optical coupler 22. First baffle 30. Driving device 31. Bracket 311, channel 312, third groove 313, third avoidance slot 32, motor 321, screw rod 322, rotating rod 33. Plunger assembly 331. Plunger rod 332. Plunger connector 333. Second avoidance groove 334, threaded connection portion 34, guide assembly 341, vertical guide groove 342, guide column 40. Second detection device 41. Second optical coupler 42. Second baffle 50. TIP head 60. First sealing ring 70. Sealing element 80. Mounting plate 81. Fourth groove. DETAILED DESCRIPTION

[0020] First of all, it should be noted that in the description of the present invention, the terms "up", "down", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0021] Please refer to Figures 1 to 5 As shown, it shows the specific structure of various preferred embodiments of the present invention, including a pump body 10, a first detection device 20, a driving device 30 and a second detection device 40.

[0022] The pump body 10 includes a cavity 11, a push assembly 12 and an adapter plug 13 for inserting the TIP head 50. The push assembly 12 includes a push block 121 and a push rod 122 connected to the bottom of the push block 121. The push rod 122 is provided with a spring 123. The top of the cavity 11 is downwardly recessed with a first groove 111. The push block 121 is movably arranged in the first groove 111 and the top of the push block 121 exceeds the first groove 111. The bottom wall of the first groove 111 is downwardly provided with a through hole 112 that penetrates the cavity 11. The bottom of the push rod 122 passes through the through hole 112 and is provided with an anti-slip portion 124. The top of the through hole 112 is provided with an abutting groove 113. The two ends of the spring 123 respectively abut against the bottom of the push block 121 and the bottom of the abutting groove 113. The bottom of the cavity 11 is upwardly provided with an accommodating cavity 114 connected to the first groove 111 for the plunger rod 331 to be slidably connected. The bottom of the adapter plug 13 is connected to the top of the accommodating cavity 114. The top of the adapter plug 13 passes through the push block 121 upward and protrudes from the top of the push block 121. Specifically, see Figure 2 and Figure 3 As shown, the push block 121 includes a push rod connecting portion 125 and a sleeve portion 126 extending upward from the top of the push rod connecting portion 125, and the top of the adapter plug 13 is exposed at the top of the sleeve portion 126; the bottom of the adapter plug 13 is convexly provided with a mounting portion 131, and the mounting portion 131 is interference-fitted with the top of the accommodating cavity 114, and a first sealing ring 60 is sandwiched between the bottom of the adapter plug 13 and the cavity 11, and the first sealing ring 60 is located at the outer periphery of the mounting portion 131; the bottom of the cavity 11 is provided with a sealing member mounting groove 115 on the outer periphery of the accommodating cavity 114, and a sealing member 70 is provided in the sealing member mounting groove 115 and is sleeved on the outer periphery of the plunger rod 331, and the sealing member 70 includes a second sealing ring and an O-ring provided on the top of the second sealing ring; Preferably, see Figure 5As shown, the bottom of the push rod connecting part 125 is recessed upwardly with a second groove 127, and correspondingly, the bottom wall of the first groove 111 is convexly provided with a boss 116 matching the second groove 127, and the boss 116 is located at the outer periphery of the top of the accommodating cavity 114, and a guide surface is provided at the second groove 127 to facilitate the plug-in guide of the push rod connecting part 125; the spring 123, the through hole 112, and the push rod 122 are each provided with two, and the two push rods 122 are arranged on opposite sides of the push block 121, so that the push of the push block 121 is smoother; in this embodiment, the cavity 11 can be provided with a plurality of empty grooves for weight reduction, and the empty grooves are arranged around the outer periphery of the first groove 111 and the accommodating cavity 114 to reduce the weight of the cavity 11 and make the whole body lighter.

[0023] The first detection device 20 is used to detect whether a TIP head 50 is inserted on the push block 121. The first detection device 20 includes a first optical coupler 21 arranged on the cavity 11 and a first baffle 22 connected to the bottom of the push block 121. The first baffle 22 is integrally formed with the push rod connecting portion 125, and a first avoidance groove 117 is provided at the bottom of the first groove 111 for the first baffle 22 to move around.

[0024] The driving device 30 includes a bracket 31, a motor 32, a plunger assembly 33 and a guide assembly 34. The bracket 31 is connected to the bottom of the pump body 10. The bracket 31 is provided with a channel 311 that passes through from top to bottom. The motor 32 is arranged at the bottom of the bracket 31. The top of the motor 32 is connected to a screw rod 321 that extends into the channel 311. The plunger assembly 33 includes a plunger rod 331 and a plunger connector 332 connected to the bottom of the plunger rod 331. The top of the plunger rod 331 is slidably connected to the accommodating chamber 114. The plunger connector 332 A second avoidance groove 333 is opened upward at the bottom, and a threaded connection part 334 threadedly connected to the screw rod 321 is provided at the bottom of the second avoidance groove 333. The guide assembly 34 includes a vertical guide groove 341 and a guide column 342 matched with the vertical guide groove 341. The vertical guide groove 341 is opened on the outer periphery of the plunger connector 332. The guide column 342 is fixed on the bracket 31. The motor 32 can drive the plunger connector 332 to press the anti-slip part 124 upward. Preferably, the guide assembly 34 is provided with two relatively arranged ones, so that the guidance is more accurate and stable; See also Figure 3 and Figure 4As shown, a mounting plate 80 is provided at the bottom of the cavity 11, and the mounting plate 80 fixes the seal 70 in the seal mounting groove 115. The bracket 31 is fixed to the bottom of the cavity 11 through the mounting plate 80. The top of the bracket 31 is downwardly provided with a third groove 312 at the periphery of the channel 311, and the bottom of the anti-slip portion 124 can partially abut against the bottom wall of the third groove 312. The bottom of the mounting plate 80 is upwardly concavely provided with a fourth groove 81, and the top of the anti-slip portion 124 is limited by the top wall of the fourth groove 81. The motor 32 has a rotating rod 322, and the screw rod 321 is interference fit with the periphery of the rotating rod 322 and is fixed by glue dispensing; the plunger rod 331 and the plunger connector 332 are fixed by glue dispensing.

[0025] The second detection device 40 is used to identify the operating position of the micro-plunger pump, find the detection position as the zero position before operation, and then calculate the suction and discharge action requirements of the micro-plunger pump based on this position. The second detection device 40 includes a second optical coupler 41 arranged on the bracket 31 and a second baffle 42 connected to the outer periphery of the plunger connector 332. The outer periphery of the plunger connector 332 is concavely provided with a groove, and the second baffle 42 is fixed in the groove by glue dispensing. The channel 311 is provided with a third avoidance groove 313 for the second baffle 42 to move around.

[0026] In this embodiment, the push assembly 12, cavity 11, bracket 31, mounting plate 80, etc. can be manufactured by injection molding. Compared with the traditional pipette, most of the parts are machined. Under the conditions of mass production, the pipette modified from the plunger pump can significantly reduce the cost compared with the traditional pipette.

[0027] The working principle of this embodiment is described in detail as follows: When the motor 32 rotates, the kinematic pair formed by the screw rod 321 and the plunger connector 332 converts the rotation of the screw rod 321 into the up and down linear motion of the plunger connector 332, and the plunger connector 332 then drives the plunger rod 331 to move up and down in the accommodating chamber 114 to achieve the effect of expanding or compressing air, thereby realizing the function of sucking and discharging liquid; When the plunger connector 332 reaches the highest position, the plunger connector 332 will push the push rod 122. At this time, due to the setting of the spring 123, the elastic force of the spring 123 will drive the push block 121 to move upward. After moving to a certain distance, the push block 121 will push off the TIP head 50 inserted on the adapter plug 13. After being pushed off, the push block 121 will return to the position supported by the spring 123. At this time, the first detection device 20 can detect that the original light-blocking part of the first baffle 22 no longer blocks light, thereby obtaining a conclusion that the TIP head 50 has been pushed off. Otherwise, it is proved that the TIP head 50 is still inserted in the adapter plug 13. When the TIP head 50 is installed on the adapter plug 13 , the spring 123 is compressed, so that the bottom of the anti-detachment portion 124 abuts against the bottom wall of the third groove 312 .

[0028] The design emphasis of the present invention is: Mainly, by providing a first groove, the push block can be retracted into the first groove, so that the overall volume of the micro plunger pump is smaller, and the motor can drive the plunger connector to press the anti-detachment part upward, so that the push block can automatically push the TIP head away from the adapter plug under the elastic force of the spring, thereby realizing automatic disassembly of the TIP head. At the same time, the setting of the spring can ensure that after the TIP head is removed from the adapter plug, the adapter plug will not shake at will and produce abnormal noise. In conjunction with the setting of the first detection device and the second detection device, after the plunger connector runs to the top, the first detection device can be used to further ensure whether the TIP head is inserted into the adapter plug, and the screw rod, the plunger connector, and the plunger rod are arranged together in the channel, which reasonably utilizes the internal space of the plunger pump, and uses the guide structure of the guide column and the vertical guide groove. Compared with the slide rail structure, the production cost of the plunger pump can be further reduced, and the structural design is ingenious.

[0029] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A micro plunger pump for pipetting, characterized in that: include: The pump body comprises a cavity, a pushing assembly and an adapter plug for inserting a TIP head, the pushing assembly comprises a pushing block and a pushing rod connected to the bottom of the pushing block, the pushing rod outer sleeve is provided with a spring, the top of the cavity is downwardly concavely provided with a first groove, the pushing block is movably arranged in the first groove and the top of the pushing block exceeds the first groove, the bottom wall of the first groove is downwardly provided with a through hole penetrating the cavity, the bottom of the pushing rod passes through the through hole and is provided with an anti-slip portion, the top of the through hole is provided with an abutting groove, the two ends of the spring respectively abut against the bottom of the pushing block and the bottom of the abutting groove, the bottom of the cavity is upwardly provided with a accommodating cavity for sliding connection of the plunger rod and communicating with the first groove, the bottom of the adapter plug is connected to the top of the accommodating cavity, and the top of the adapter plug passes through the pushing block upward and protrudes from the top of the pushing block; A first detection device, the first detection device is used to detect whether a TIP head is inserted on the push block, the first detection device comprises a first optical coupler arranged on the cavity and a first baffle connected to the bottom of the push block, and a first avoidance groove for the first baffle to move away is provided at the bottom of the first groove; A driving device, the driving device includes a bracket, a motor, a plunger assembly and a guide assembly, the bracket is connected to the bottom of the pump body, the bracket is provided with a channel running through from top to bottom, the motor is arranged at the bottom of the bracket, the top of the motor is connected with a screw rod extending into the channel, the plunger assembly includes a plunger rod and a plunger connector connected to the bottom of the plunger rod, the top of the plunger rod is slidably connected to the accommodating cavity, the bottom of the plunger connector is provided with a second avoidance groove upwards, the bottom end of the second avoidance groove is provided with a threaded connection part threadedly connected to the screw rod, the guide assembly includes a vertical guide groove and a guide column matching the vertical guide groove, one of the vertical guide groove and the guide column is arranged on the outer periphery of the plunger connector, and the other is arranged on the bracket, and the motor can drive the plunger connector to press upward against the anti-slip part; The second detection device is used to identify the operating position of the micro plunger pump. The second detection device includes a second optical coupler arranged on the bracket and a second baffle connected to the outer periphery of the plunger connector. The channel is provided with a third avoidance groove for the second baffle to move around.

2. A micro plunger pump for pipetting according to claim 1, characterized in that: The push block comprises a push rod connecting portion and a sleeve portion extending upward from the top of the push rod connecting portion, and the top of the adapter plug protrudes from the top of the sleeve portion.

3. A micro plunger pump for pipetting according to claim 2, characterized in that: A second groove is recessed upwardly at the bottom of the push rod connecting part, and correspondingly, a boss matching the second groove is protruded from the bottom wall of the first groove, and the boss is located at the outer periphery of the top end of the accommodating cavity.

4. A micro plunger pump for liquid transfer according to claim 1, characterized in that: The spring, the through hole and the push rod are all provided with two, and the two push rods are arranged on the opposite sides of the push block.

5. A micro plunger pump for liquid transfer according to claim 1, characterized in that: The bottom of the adapter plug is convexly provided with a mounting portion, the mounting portion is interference fit with the top of the accommodating cavity, a first sealing ring is sandwiched between the bottom of the adapter plug and the cavity, and the first sealing ring is located on the periphery of the mounting portion.

6. A micro plunger pump for liquid transfer according to claim 1, characterized in that: The cavity is provided with a plurality of empty slots for reducing weight.

7. A micro plunger pump for liquid transfer according to claim 1, characterized in that: A mounting plate is provided at the bottom of the cavity, and the bracket is fixed to the bottom of the cavity through the mounting plate.

8. A micro plunger pump for liquid transfer according to claim 7, characterized in that: A sealing member installation groove is provided at the bottom of the cavity on the periphery of the accommodating cavity, a sealing member sleeved on the periphery of the plunger rod is arranged in the sealing member installation groove, and the installation plate fixes the sealing member in the sealing member installation groove.

9. A micro plunger pump for liquid transfer according to claim 7, characterized in that: The top of the bracket is provided with a third groove downward on the outer periphery of the channel, the bottom of the anti-slip part can partially abut against the bottom wall of the third groove, the bottom of the mounting plate is provided with a fourth groove upward, and the top of the anti-slip part is limited by the top wall of the fourth groove.

10. A micro plunger pump for liquid transfer according to claim 1, characterized in that: The motor has a rotating rod, and the screw rod is interference-fitted with the outer circumference of the rotating rod and fixed by glue dispensing.

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