An adaptive suspension pressing device for a microfluidic chip

Abstract

The present invention relates to the technical field of pressing and sealing of microfluidic devices, and particularly relates to a pressing device for a microfluidic chip. An adaptive floating pressing device for a microfluidic chip includes a driving mechanism and a pressing device connected to the driving mechanism. The pressing device includes a floating cover plate and a plurality of groups of floating pressing heads arranged on the lower side of the floating cover plate. The floating cover plate and the floating pressing heads are connected by springs. The present invention can not only achieve complete sealing of a microfluidic chip with a single small-diameter notch, but also achieve complete pressing and sealing of a microfluidic chip with multiple notches and large-diameter notches.

Description

Technical Field

[0001] The present invention relates to the technical field of pressing and sealing of microfluidic devices, and particularly to a pressing device for a microfluidic chip. Background Art

[0002] In a microfluidic gas pressure control system, to ensure that the fluid does not leak, the flow rate is accurately regulated and the regulation range is wide, the pressing and sealing effect of the device is crucial. In a microfluidic device, the pressing and sealing of the chip is often achieved by the combination of the forward and backward displacement of the bottom chip and the up and down displacement of the top pressing member (press head). However, almost all the pressing members on the market are single-piece / monolithic and small-sized, and can only meet the pressing and sealing of single, small-sized microfluidic chips with notch. At the same time, the sealing effect has extremely high requirements for the surface machining flatness of the press head and the chip notch. Therefore, it is difficult for them to press microfluidic chips with multiple, large-sized and different-sized, and not completely flat notches. In addition, with the long-term contact wear between the press head and the chip notch, the press head will also have problems such as surface unevenness, poor wear resistance, weak corrosion resistance, and short working life, which will all lead to a decrease or failure of the sealing effect. This is also the main reason for the uneven performance of existing microfluidic operation devices in accurately controlling the flow rate and stably forming droplets. Summary of the Invention

[0003] Based on the above practical problems, the present invention proposes the concept and structure of a "floating press head", that is, multiple press heads are "suspended" under a pressing cover plate in the device. Each press head has degrees of freedom of tilting left and right, tilting forward and backward, and moving up and down. The press heads are relatively independent of each other, so as to be able to fully press the multiple notches of the chip below with multi-point contact. The above problems in the existing pressing and sealing technology field are successfully solved. The technical solution of the present invention realizes the complete pressing of microfluidic chips with multiple, large-sized notches of various sizes, well ensures the sealing effect, reduces the requirement for the flatness of the press head and chip processing, and can ensure the accurate regulation of the flow rate with simple operation.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] An adaptive floating pressing device for a microfluidic chip, comprising a driving mechanism, and a pressing device connected to the driving mechanism. The pressing device includes a floating cover plate, and multiple groups of floating press heads arranged on the lower side of the floating cover plate. A spring is connected between the floating cover plate and the floating press heads.

[0006] Further, a press head groove is provided on the bottom side of the floating cover plate, and the floating press heads are arranged in the press head groove.

[0007] Further, an air inlet is provided on the circumferential side of each group of suspension heads, and an air outlet is provided on the bottom side. The air inlet is communicated with the air outlet, and the air inlet is connected to an air inlet pipe.

[0008] Further, a first air inlet is provided on the circumferential side of each group of suspension heads, a first air outlet is provided on the other circumferential side, and a second air outlet is provided on the bottom side. The air inlet is communicated with the air outlet, and the first air outlet and the first air inlet between adjacent groups of suspension heads are connected by a conduit.

[0009] Further, the adaptive suspension pressing device further includes a soft material gasket independently provided between the pressing device and the notch of the chip sample pool. Through holes are provided on the soft material gasket, and the positions of the through holes correspond to the second air outlets on the suspension heads distributed on the lower side of the suspension cover plate.

[0010] Further, a head fixing frame, a fixing frame limiting block, and suspension heads are sequentially arranged on the lower side of the suspension cover plate. The fixing frame limiting block includes a first table block and a second table block provided on the lower side of the first table block. The upper side surface of the first table block is fixedly connected to the lower side surface of the suspension cover plate. The head fixing frame is a square frame with openings on both the upper and lower side surfaces. The area of the square opening on the upper side surface of the head fixing frame is larger than the upper surface area of the first table block and smaller than the lower surface area of the second table block, so that the first table block can freely enter and exit the square opening on the upper side surface. The area of the opening on the lower side surface of the head fixing frame is larger than the lower surface area of the second table block. The suspension heads are fixedly connected to the head fixing frame. A spring sleeving column is provided on the upper side surface of the suspension heads. A sleeve column accommodating cavity is provided on the lower side of the second table block for accommodating the spring sleeving column, and a spring is arranged on the spring sleeving column. The head fixing frame and the suspension heads cover the fixing frame limiting block in the connection space between the two and leave a certain activity space.

[0011] Further, screw holes are provided on the circumferential side of the head fixing frame, and screw holes are also provided on the circumferential side of the suspension heads. When the suspension heads are fixed to the head fixing frame, the suspension heads are placed inside the head fixing frame, and the screw holes can be connected by screws. In the above solution, the fixing frame limiting block is fixed to the suspension pressing plate, and the head fixing frame and the suspension heads cover it and can move appropriately under its limited fixation. This fixing method can greatly stabilize the suspension heads during the working process of the suspension heads, avoid deviation, and avoid excessive movement and poor working effect.

[0012] Further, the driving mechanism includes a bracket, a horizontal moving structure, and a vertical moving structure provided on the bracket, and the suspension cover plate is connected to the bottom end of the vertical moving structure.

[0013] Further, the bracket includes a left side plate, a right side plate, and a top plate fixing plate provided between the left side plate and the right side plate.

[0014] Further, the horizontal movement mechanism includes a lead screw drive assembly. The lead screw drive assembly includes a lead screw and a rotating block. One end of the lead screw is connected to the output end of the driving motor, and the other end passes through and is rotatably fixed on a lead screw fixing vertical plate. The lead screw fixing vertical plate is arranged between the left side plate and the right side plate and is parallel to both of them.

[0015] Further, the rotating block is sleeved on the lead screw. The rotating block is fixedly connected to a first connecting block. A roller is arranged at the upper end of the first connecting block. The roller is in contact with the lower side surface of the top plate fixing plate. The lower end of the first connecting block is rotatably connected to a second connecting block. The lower end of the second connecting block is rotatably provided with a floating cover plate.

[0016] Further, the first connecting block and the second connecting block are connected by a second rotating shaft, and the upper end of the first connecting block and the roller are connected by a first rotating shaft.

[0017] Further, limiting plates are respectively arranged on both sides of the first connecting block. The limiting plates are respectively in contact with or slidably connected to the front and rear sides of the first connecting block. The two ends of the limiting plates are respectively fixed on the housing of the driving motor and the lead screw fixing plate.

[0018] Further, the left side plate includes a first vertical portion. A first horizontal portion is arranged at the upper end of the first vertical portion. A first threaded hole is arranged on the first horizontal portion. A row of through holes is arranged on the part of the upper end of the first vertical portion close to the lower side of the first horizontal portion. Second threaded holes are arranged on the end faces at both ends of the top plate fixing plate. Bolts pass through the through holes and cooperate with the second threaded holes to complete the fixation. The diameter of the through holes is smaller than the bolt head and larger than the bolt rod. In this solution, the through holes can be arranged in multiple rows at intervals up and down.

[0019] Further, the through holes may not be arranged in a perfect circle, or may be vertically elongated. The width of the vertically elongated through holes is smaller than the bolt head and larger than the bolt rod. In the above two design solutions, the up and down adjustment of the top plate fixing plate can be achieved by connecting with bolts through the side through holes and the second threaded holes. Further, the fixation is strengthened by the bolts passing through the second threaded holes and pressing against the upper side surface of the top plate fixing plate.

[0020] Further, the longitudinal movement mechanism includes a third connecting block fixed to the lower side of the top plate fixing plate and a fourth connecting block slidably connected to the third connecting block. The fourth connecting block is fixedly connected to the floating cover plate.

[0021] Further, a slide rail or a slider is arranged on the third connecting block, and a slider or a slide rail matched with it is arranged on the fourth connecting block.

[0022] The technical solution adopted by the present invention for pressing and sealing the chip is achieved by driving the up-and-down displacement of the pressing device through a motor, so that the pressing head closely adheres to the notch of the chip sample cell. The floating pressing head is independently processed, and multiple floating pressing heads are all floatingly installed under the same floating cover plate to form the "floating pressing head". The advantages of the floating pressing head are reflected in that each pressing head has a certain degree of freedom of left-right tilt, front-back tilt, and up-down movement; and each pressing head is relatively independent. Therefore, each pressing head can generate its own independent adaptive offset amount (adjustment in horizontal angle or height) according to the downward pressure given by the connecting rod and the processing conditions of the contact surface between the floating pressing head and the chip notch (notch shape, size, and flatness) during the downward pressing process, presenting multi-point contact with the microfluidic chip, thereby achieving complete pressing and sealing. At the same time, the air inlet interface and the gas path part of the device are completely processed at the independent pressing head to ensure that the input air flow does not leak and accurately control the flow rate. In addition, in actual assembly operations, a soft material gasket such as rubber is placed between the pressing head and the notch of the chip sample cell, which can reduce the wear during the pressing process of the pressing head and the chip, and improve the compactness during contact. The present invention can achieve complete pressing and sealing of microfluidic chips with multiple notches and large-size apertures, and at the same time greatly reduce the requirements for the processing flatness of the pressing head and the notch of the chip sample cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of a specific embodiment of the present invention.

[0024] Figure 2 It is a schematic structural diagram of a specific embodiment of the present invention.

[0025] Figure 3 It is a schematic partial structural diagram of a specific embodiment of the present invention.

[0026] Figure 4 It is a schematic diagram of another perspective of a partial structure of a specific embodiment of the present invention.

[0027] Figure 5 It is a schematic structural diagram of the floating pressing head of a specific embodiment of the present invention.

[0028] Figure 6 It is a schematic structural diagram of the driving mechanism of a specific embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following further explains the technical solution of the present invention with reference to the drawings.

[0030] Example 1:

[0031] An adaptive suspension pressing device for a microfluidic chip, comprising a driving mechanism and a pressing device connected to the driving mechanism, characterized in that: the pressing device includes a suspension cover plate 5, and a plurality of groups of suspension pressing heads 6 arranged on the lower side of the suspension cover plate 5, and the suspension cover plate 5 and the suspension pressing heads 6 are connected by springs.

[0032] A pressing head groove is provided on the bottom side of the suspension cover plate 5, and the suspension pressing heads are arranged in the pressing head groove.

[0033] On the circumferential side surface of each group of suspension pressing heads 6, a first air inlet 7 is provided, on the other circumferential side surface, a first air outlet 8 is provided, and on the bottom side surface, a second air outlet 9 is provided. The air inlet and the air outlet are communicated, and the first air outlet 8 and the first air inlet 9 between adjacent two groups of suspension pressing heads are connected by a conduit 14.

[0034] The adaptive suspension pressing device further includes a soft material gasket 11 independently arranged between the pressing device and the chip sample cell notch 10. A through hole 12 is provided on the soft material gasket 11, and the setting position of the through hole 12 corresponds to the second air outlet 9 on the suspension pressing heads 6 distributed on the lower side of the suspension cover plate 5.

[0035] Example 2:

[0036] An adaptive suspension pressing device for a microfluidic chip, comprising a driving mechanism and a pressing device connected to the driving mechanism, characterized in that: the pressing device includes a suspension cover plate 5, and a plurality of groups of suspension pressing heads 6 arranged on the lower side of the suspension cover plate 5, and the suspension cover plate 5 and the suspension pressing heads 6 are connected by springs.

[0037] A pressing head groove is provided on the bottom side of the suspension cover plate 5, and the suspension pressing heads are arranged in the pressing head groove.

[0038] On the circumferential side surface of each group of suspension pressing heads 6, an air inlet 7 is provided, on the bottom side surface, an air outlet 9 is provided, the air inlet 7 and the air outlet 9 are communicated, the air inlet 7 is connected to an air inlet pipe, and a plurality of air outlets 9 are provided on the lower side of each suspension pressing head 6.

[0039] The adaptive suspension pressing device further includes a soft material gasket 11 independently arranged between the pressing device and the chip sample cell notch 10. A through hole 12 is provided on the soft material gasket 11, and the setting position of the through hole 12 corresponds to the air outlet 9 on the suspension pressing heads 6 distributed on the lower side of the suspension cover plate 5.

[0040] Example 3:

[0041] The present invention provides a specific connection structure between a floating pressure plate and a floating pressure head. The specific solution is as follows: A pressure head fixing frame 51, a fixing frame limiting block 52, and a floating pressure head 6 are sequentially arranged on the lower side of the floating cover plate 5. The fixing frame limiting block 52 includes a first table block 522 and a second table block 521 arranged on the lower side of the first table block 522. The upper side surface of the first table block 522 is fixedly connected to the lower side surface of the floating cover plate 5. The pressure head fixing frame 51 is a square frame with openings on both the upper and lower side surfaces. The area of the square opening on the upper side surface of the pressure head fixing frame 51 is larger than the upper surface area of the first table block 522 and smaller than the lower surface area of the second table block 521, so that the first table block 522 can freely enter and exit the square opening on the upper side surface. The opening area of the lower side surface of the pressure head fixing frame 51 is larger than the lower surface area of the second table block 521. The floating pressure head 6 is fixedly connected to the pressure head fixing frame 51. A spring sleeving column 55 is arranged on the upper side surface of the floating pressure head 6. A sleeve column accommodating cavity is arranged on the lower side of the second table block 521 for accommodating the spring sleeving column 55, and a spring is arranged on the spring sleeving column 55.

[0042] Further, screw holes are arranged on the peripheral side of the pressure head fixing frame 51, and screw holes 54 are also arranged on the peripheral side of the floating pressure head 6. When the floating pressure head 6 is fixed to the pressure head fixing frame 51, the floating pressure head 6 is placed inside the pressure head fixing frame, and the screw holes are connected by screws. In the above solution, the fixing frame limiting block is fixed to the floating pressure plate, and the pressure head fixing frame and the floating pressure head cover it and can move appropriately under its limited fixation. This fixing method can greatly stabilize the floating pressure head during the working process of the floating pressure head, avoid the offset of the pressure head, and avoid excessive movement and poor working effect.

[0043] The driving mechanism includes a bracket 1, a horizontal moving structure and a vertical moving structure arranged on the bracket 1. The floating cover plate 5 is connected to the bottom end of the vertical moving structure.

[0044] The bracket 1 includes a left side plate 94, a right side plate 95, and a top plate fixing plate 96 arranged between the left side plate 94 and the right side plate 95.

[0045] The horizontal moving mechanism includes a lead screw transmission assembly. The lead screw transmission assembly includes a lead screw 97 and a rotating block 98. One end of the lead screw 97 is connected to the output end of a driving motor 94, and the other end passes through and is rotatably fixed on a lead screw fixing vertical plate 100. The lead screw fixing vertical plate 100 is arranged between the left side plate 94 and the right side plate 95 and is parallel to both of them.

[0046] The rotating block 98 is sleeved on the lead screw 97. The rotating block 98 is fixedly connected to the first connecting block 99. A roller 101 is arranged at the upper end of the first connecting block 99. The roller 101 is in contact with the lower side of the top plate fixing plate 96. The lower end of the first connecting block 99 is rotatably connected to a second connecting block 102. The lower end of the second connecting block 102 is rotatably provided with a floating cover plate 5.

[0047] The first connecting block 99 and the second connecting block 102 are connected by a second rotating shaft 103. The upper end of the first connecting block 99 and the roller 101 are connected by a first rotating shaft 104.

[0048] Limit plates 105 are respectively arranged on both sides of the first connecting block 99. The limit plates 105 are respectively in contact with or slidably connected to the front and rear sides of the first connecting block 99. Both ends of the limit plates 105 are fixed on the housing of the driving motor 92 and the lead screw fixing plate 100.

[0049] The left side plate 94 includes a first vertical portion. A first horizontal portion 106 is arranged at the upper end of the first vertical portion. A first threaded hole 107 is arranged on the first horizontal portion 106. A through hole 108 is arranged on the portion of the upper end of the first vertical portion near the lower side of the first horizontal portion. Second threaded holes are arranged on the end faces of both ends of the top plate fixing plate 96. Bolts pass through the through holes 108 and cooperate with the second threaded holes to complete the fixation. The diameter of the through hole 108 is smaller than the bolt head and larger than the bolt rod. In this solution, the through holes can be arranged in multiple rows at intervals up and down.

[0050] The through hole 108 may not be arranged as a perfect circle, or it may be a vertical long strip. The width of the long strip through hole is smaller than the bolt head and larger than the bolt rod. In the above two design solutions, the up and down adjustment of the top plate fixing plate can be achieved by connecting with the second threaded hole through the side through hole 108 with a bolt. Further, the fixation is strengthened by the bolt passing through the second threaded hole and pressing against the upper side of the top plate fixing plate.

[0051] The longitudinal moving mechanism includes a third connecting block 109 fixed to the lower side of the top plate fixing plate and a fourth connecting block 110 slidably connected to the third connecting block. The fourth connecting block 110 is fixedly connected to the floating cover plate 5.

[0052] A slide rail 112 is arranged on the third connecting block 109. A slider 111 is arranged on the fourth connecting block 110 and is matched with the slide rail 112.

[0053] In summary, the present invention can not only completely seal a microfluidic chip with a single small-diameter notch, but also completely compress and seal a microfluidic chip with multiple notches or large-diameter notches; the present invention also has very low requirements for the processing flatness of its indenter and the notch of the chip sample cell; the air inlet interface and the gas path part of the device are both processed on an independent indenter, with no air leakage and accurate flow control. The present invention has the advantages of self-adaptive adjustment of compression sealing, wear resistance of components, anti-loosening, anti-extrusion, and convenient installation and use.

Claims

1. An adaptive suspension pressing device for a microfluidic chip, characterized in that: The pressing device includes a floating cover plate, a plurality of floating pressing heads arranged on the lower side of the floating cover plate, and the floating cover plate and the floating pressing heads are connected by springs; a pressing head groove is arranged on the bottom side of the floating cover plate, and the floating pressing heads are arranged in the pressing head groove; an air inlet is arranged on the circumferential side of each group of floating pressing heads, and an air outlet is arranged on the bottom side, and the air inlet is communicated with the air outlet, and the air inlet is connected with an air inlet pipe; a first air inlet is arranged on the circumferential side of each group of floating pressing heads, a first air outlet is arranged on the other circumferential side, and a second air outlet is arranged on the bottom side, and the air inlet is communicated with the air outlet, and the first air outlet and the first air inlet between adjacent two groups of floating pressing heads are connected by a guide pipe; the adaptive floating pressing device further includes a soft material gasket independently arranged between the pressing device and the notch of the chip sample cell, and through holes are arranged on the soft material gasket, and the arrangement positions of the through holes correspond to the second air outlets on the floating pressing heads distributed on the lower side of the floating cover plate; the adaptive floating pressing device further includes a driving mechanism, and the driving mechanism includes a bracket, a horizontal moving structure and a vertical moving structure arranged on the bracket, and the floating cover plate is connected to the bottom end of the vertical moving structure; the bracket includes a left side plate, a right side plate and a top plate fixing plate arranged between the left side plate and the right side plate, the horizontal moving structure includes a lead screw transmission assembly, the lead screw transmission assembly includes a lead screw and a rotating block, the rotating block is sleeved on the lead screw, the rotating block is fixedly connected with a first connecting block, a roller is arranged at the upper end of the first connecting block, the roller is in contact with the lower side of the top plate fixing plate, the lower end of the first connecting block is rotatably connected with a second connecting block, and the lower end of the second connecting block is rotatably provided with a floating cover plate, and the vertical moving structure includes a third connecting block fixed on the lower side of the top plate fixing plate and a fourth connecting block slidably connected with the third connecting block, and the fourth connecting block is fixedly connected with the floating cover plate.

2. The adaptive suspension pressing device for a microfluidic chip according to claim 1, characterized in that: The left side plate includes a first vertical portion, a first horizontal portion is arranged at the upper end of the first vertical portion, a first threaded hole is arranged on the first horizontal portion, through holes are arranged on the portion of the upper end of the first vertical portion close to the lower side of the first horizontal portion, second threaded holes are arranged on the end faces of both ends of the top plate fixing plate, and bolts pass through the through holes and cooperate with the second threaded holes to complete the fixation. The diameter of the through holes is smaller than the bolt head and larger than the bolt rod, and the through holes are arranged in multiple rows at intervals up and down.

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