阅读说明：本技术 微流控负压驱动常开微阀 (Micro-fluidic negative pressure driving normally-open micro valve ) 是由 周洲 张昆鹏 姚守菊 孙道恒 于 2019-10-22 设计创作，主要内容包括：本发明公开了微流控负压驱动常开微阀,包括阀体和阀芯,所述阀体上设置阀腔,阀腔上设置常开的输入端和输出端；所述阀芯位于阀腔内,所述阀芯内部中空,所述阀芯具有随阀芯内外压力变化而发生形变性,阀芯上具有负压输入端,负压进入阀芯内部让所述阀芯形变将输入端和或输出端封堵使阀门关闭。本发明中实现了负压信号控制正压信号通断,能带来大的变形和较高的输出变化量；主要用于微流控芯片中,安全可靠性更高,容易实现类似数字电路中接地以及信号增益等功能的,实现了非门、与门以及或门等多种功能,并可以通过等效电路的设计方法实现气动信号的存储、振荡等高层次应用。(The invention discloses a microfluidic negative pressure driven normally-open micro valve, which comprises a valve body and a valve core, wherein the valve body is provided with a valve cavity, and the valve cavity is provided with a normally-open input end and a normally-open output end; the valve core is positioned in the valve cavity, the valve core is hollow, the valve core has deformation along with the change of the internal pressure and the external pressure of the valve core, the valve core is provided with a negative pressure input end, and negative pressure enters the valve core to deform the valve core so as to plug the input end and/or the output end to close the valve. According to the invention, the negative pressure signal is used for controlling the on-off of the positive pressure signal, so that large deformation and higher output variable quantity can be brought; the pneumatic signal generator is mainly used in a microfluidic chip, has higher safety and reliability, is easy to realize the functions of grounding, signal gain and the like in a digital circuit, realizes multiple functions of a NOT gate, an AND gate, an OR gate and the like, and can realize high-level application of pneumatic signals such as storage, oscillation and the like by a design method of an equivalent circuit.)

1. The micro-fluidic negative pressure drive normally-open micro valve is characterized in that: the valve comprises a valve body and a valve core, wherein the valve body is provided with a valve cavity, and the valve cavity is provided with a normally open input end and a normally open output end; the valve core is positioned in the valve cavity, the valve core is hollow, the valve core has deformation along with the change of the internal pressure and the external pressure of the valve core, the valve core is provided with a negative pressure input end, and negative pressure enters the valve core to deform the valve core so as to plug the input end and/or the output end to close the valve.

2. The microfluidic negative-pressure driven normally-open microvalve of claim 1, wherein: the valve core comprises a deformation part, a connecting part and a base part, wherein the connecting part is connected with the base part through the deformation part, the connecting part and the base part form a polyhedron with a long axis and a short axis, and the long axis and the short axis are mutually vertical; the long shaft is collinear with the input end and/or the output end; the section of the valve core on the surface of the long shaft is of an axisymmetric structure about the long shaft; the valve core is fixed in the valve cavity through the base part; when the pressure in the valve core is reduced, at least the deformation part on the valve core deforms, the deformation part moves along the long axis to drive the connecting part to move along the short axis, and the deformation part seals the input end and/or the output end to close the valve.

3. The microfluidic negative-pressure driven normally-open microvalve of claim 2, wherein: the section of the valve core on the plane of the short shaft is of an axisymmetric structure relative to the short shaft.

4. The microfluidic negative-pressure driven normally-open microvalve of claim 3, wherein: the section of the valve core cut along the long axis is one of an ellipse, a diamond, a hexagon and an octagon.

5. The microfluidic negative-pressure driven normally-open microvalve of claim 2, wherein: the two deformation parts at the two ends of the connecting part have different structures, and the deformation parts are arc-shaped or wedge-shaped.

6. The microfluidic negative-pressure-driven normally-open microvalve according to any one of claims 1 to 5, wherein: at least the deformation part in the deformation part, the connecting part and the base part is an elastic material layer.

7. The microfluidic negative-pressure-driven normally-open microvalve according to any one of claims 1 to 5, wherein: the thickness of the deformation part is smaller than that of the base part, and the thickness of the deformation part is smaller than that of the connecting part.

8. The microfluidic negative-pressure driven normally-open microvalve of claim 6, wherein: the elastic material is rubber.

Technical Field

The invention relates to a digital microfluidic pressure logic control chip, in particular to a microfluidic negative pressure driven normally-open micro valve.

Background

Digital microfluidics is a novel pneumatic logic control technology appearing in recent years, and has wider application along with the development of modern robot systems towards the direction of biochemical simulation and flexibility, particularly the appearance of pneumatic flexible actuator structures. The technology realizes the logic controllable regulation of the signal of an output channel along with an input signal by constructing a micro valve array system with digital logic, regarding a micro valve as a transistor in a digital circuit and regarding a flow channel as a lead, wherein the input signal can be air pressure or a corresponding hydraulic signal. However, the output signal is always negative vacuum pressure, and for the pneumatic flexible actuator at present, a negative pressure structure cannot bring large deformation and high output variable quantity, so that specially designed components are needed to convert the negative pressure signal output by the digital microfluidic logic chip into positive pneumatic or hydraulic pressure which can be directly used for driving the flexible actuator. Such components are typically represented as microvalves of the mold cavity structure.

According to the difference of signals and initial working states, two micro-valve structures exist in the micro-fluidic field at present, a normally open micro-valve with positive pressure for control signals and controlled signals and a normally closed micro-valve with negative pressure for both are adopted, the structural characteristics of the normally open micro-valve and the normally closed micro-valve are both upper and lower runner level middle layer plane film structures, the film moves and deforms towards which side runner, and the runner is in a closed state. When both ends are under the action of pressure, the structural characteristic that the planar film moves towards the direction of lower pressure determines that a high-pressure area is a control signal and a low-pressure area is a controlled signal, so that in the traditional aspect, a negative pressure signal is difficult to control the on-off of a positive pressure signal, namely, a normally-open micro valve driven by negative pressure does not exist.

Disclosure of Invention

The invention aims to provide a microfluidic negative-pressure-driven normally-open micro valve, which can solve one or more of the technical problems.

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

the microfluidic negative-pressure driven normally-open micro valve comprises a valve body and a valve core, wherein the valve body is provided with a valve cavity, and a normally-open input end and a normally-open output end are arranged on the valve cavity; the valve core is positioned in the valve cavity, the valve core is hollow, the valve core has deformation along with the change of the internal pressure and the external pressure of the valve core, the valve core is provided with a negative pressure input end, and negative pressure enters the valve core to deform the valve core so as to plug the input end and/or the output end to close the valve.

The invention realizes that the on-off of a positive pressure signal is controlled by a negative pressure signal, and the normally open micro valve is driven by negative pressure; in the invention, the pressure lower than the input end and the output end is introduced into the valve core, so that the input end or the output end is used as the power of the valve per se, the valve core is deformed, and then the on-off of the valve is controlled; and the situation that the valve cannot be tightly closed due to the pressure difference between two ends of the valve core is not worried about.

The valve body and the valve core are manufactured in an assembly or integrated 3D printing mode, and the rest parts of the valve body except the first input end and the positive pressure signal output end are sealed in the assembly process.

A specific valve core structure is provided; the valve core comprises a deformation part, a connecting part and a base part, wherein the connecting part is connected with the base part through the deformation part, the connecting part and the base part form a polyhedron with a long axis and a short axis, and the long axis and the short axis are mutually vertical; the long shaft is collinear with the input end and/or the output end; the section of the valve core on the surface of the long shaft is of an axisymmetric structure about the long shaft; the valve core is fixed in the valve cavity through the base part; when the pressure in the valve core is reduced, at least the deformation part on the valve core deforms, the deformation part moves along the long axis to drive the connecting part to move along the short axis, and the deformation part seals the input end and/or the output end to close the valve.

Further: the section of the valve core on the plane of the short shaft is of an axisymmetric structure relative to the short shaft.

Further: the section of the valve core cut along the long axis is one of an ellipse, a diamond, a hexagon and an octagon.

The regular shape is easy to process and manufacture.

Further: the two deformation parts at the two ends of the connecting part have different structures, and the deformation parts are arc-shaped or wedge-shaped. So that the section of the whole valve core along the surface of the long shaft is approximately fan-shaped. The deformation part with the large arc length points to a port needing to be plugged in the valve cavity, and when the pressure in the valve core is reduced, the pressure in the valve cavity presses the connecting part to enable the deformation part to deform and move along the long axis to plug the port.

Further: at least the deformation part in the deformation part, the connecting part and the base part is an elastic material layer. The whole valve core can be a hollow body made of elastic materials, and also can be made of elastic materials only in the deformation part.

Further: the thickness of the deformation part is smaller than that of the base part, and the thickness of the deformation part is smaller than that of the connecting part. For better deformation of the deformation portion, the thickness of the deformation portion is smaller than other portions of the valve element.

Further: the elastic material is rubber. Or other deformable material.

The invention has the technical effects that:

according to the invention, the negative pressure signal is used for controlling the on-off of the positive pressure signal, so that large deformation and higher output variable quantity can be brought; the pneumatic signal generator is mainly used in a microfluidic chip, has higher safety and reliability, is easy to realize the functions of grounding, signal gain and the like in a digital circuit, realizes multiple functions of a NOT gate, an AND gate, an OR gate and the like, and can realize high-level application of pneumatic signals such as storage, oscillation and the like by a design method of an equivalent circuit.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In the drawings:

FIG. 1 is a schematic diagram of the general structure of the present invention;

FIG. 2 is a state diagram of the use of FIG. 1;

FIG. 3 is a first schematic structural view of the valve core and a deformation diagram of the valve core in a use state;

FIG. 4 is a second schematic structural view of the valve core and its deformation diagram in use;

FIG. 5 is a schematic structural diagram III of the valve core and a deformation diagram of the valve core in a use state;

FIG. 6 is a fourth schematic structural view of the valve core and a deformation diagram of the valve core in a use state;

fig. 7 is a schematic diagram of a valve core structure five and a use state deformation diagram thereof.

Detailed Description

The present invention will now be described in detail with reference to the drawings and specific embodiments, wherein the exemplary embodiments and descriptions are provided only for the purpose of illustrating the present invention and are not to be construed as unduly limiting the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in FIG. 1, the invention discloses a structure schematic diagram of a negative pressure driven normally open micro valve. It has the micro-flow control mould cavity micro-valve structure characteristic. The structure mainly comprises a valve body 1 and a valve core 2, wherein a valve cavity 11 is arranged on the valve body 1, and a normally open input end 12 and a normally open output end 13 are arranged on the valve cavity 11; the valve core 2 is positioned in the valve cavity 11, the valve core 2 is hollow, the valve core 2 has deformation along with the change of the internal pressure and the external pressure of the valve core, the valve core 2 is provided with a negative pressure input end 21, and negative pressure enters the valve core 2 to deform the valve core so as to plug the input end 12 and/or the output end 13 and close the valve. The switching action of the micro valve is mainly formed by the matching of the channel (input end and/or output end) in the valve body and the deformation of the valve core.

The number of the input and output ports of the whole valve body is 3, the input and output ports are respectively a negative pressure channel 14 communicated with a negative pressure input end 21, the negative pressure channel is configured with a negative pressure control signal output by a front-end micro-fluidic chip, the input end 12 is configured with a positive pressure actuating signal of a pneumatic flexible actuator, and finally, the negative pressure actuating signal is an output end 13 of a micro valve, and the output end is directly connected with the pneumatic flexible actuator. The valve core 2 in the micro valve structure is a cavity with deformation, and a negative pressure input end 21 arranged on the valve core is connected with the negative pressure channel 14, so that the transmission of a control signal of negative pressure and the micro valve is realized.

As shown in fig. 2, when the interior of the valve core is acted by a negative pressure signal inputted from a negative pressure input end 21, the valve core will present a flat shape change due to the difference between the longitudinal stress and the transverse stress applied to the valve core (the cross section of the long axis is an ellipse), which is embodied as the long axis being increased and the short axis being shortened, and two ends of the long axis, i.e. the deformation part 22, will displace in the direction of the long axis, and when the valve core deforms to a certain extent, the deformation part 22 at the end of the valve core contacts with the inlet and the outlet of the inner cavity of the valve body, and closes the flow passage at the position.

The valve core 2 comprises a deformation part 22, a connecting part 24 and a base part 23, wherein the connecting part and the base part are connected through the deformation part, the connecting part and the base part form a polyhedron with a long axis and a short axis, and the long axis and the short axis are mutually vertical; the long shaft is collinear with the input end and/or the output end; the section of the valve core on the surface of the long shaft is of an axisymmetric structure about the long shaft; the valve core is fixed in the valve cavity through the base part; when the pressure in the valve core is reduced, at least the deformation part on the valve core deforms, the deformation part moves along the long axis to drive the connecting part to move along the short axis, and the deformation part seals the input end and/or the output end to close the valve.

The structure that can generate anisotropic deformation when the inside of the valve is under the action of negative pressure is quite rich, and the structural schematic diagrams (the sectional schematic diagram of the surface where the long axis is located) of the valve cores are given below.

In certain embodiments, as shown in fig. 3, the valve element has a diamond-shaped cross-section, and the entire valve element is preferably made of an elastic material (e.g., rubber), so that the valve element is easy to manufacture and has the same use effect as an elliptical valve element.

In some embodiments, as shown in fig. 4, the cross section of the valve core is hexagonal, and the whole valve core can be made of elastic material (such as rubber), so that the valve core is simple to process and manufacture and has the same using effect as an elliptical valve core and a rhombic valve core;

in addition, the connecting part and the base part in the valve core can be made of different materials from the deformation parts at the two ends, for example, the valve core is made of plastic or aluminum alloy, and the service life of the whole valve core can be prolonged.

In some embodiments, as shown in fig. 5, the cross-section of the valve core is approximately fan-shaped, where the entire valve core may be made of an elastic material (e.g., rubber), and the valve core may be used as a single port valve, or may be used separately when the ports are not on the same axis.

As shown in fig. 6, in some embodiments, the valve core has a plurality of identical deformation portions, so that the cross section of the valve core is similar to that of a spring, which can deal with the situation that a plurality of ports are arranged on the valve body, wherein the whole valve core can be made of elastic material (such as rubber), or the connection portion and the base portion can be made of the same material, and the deformation portions are made of rubber.

As shown in fig. 7, in some embodiments, the valve core has a plurality of deformation portions, and the deformation portions are arranged differently according to the ports of the valve body, so that the cross section of the valve core is similar to that of a spring, and the situation that a plurality of different ports are arranged on the valve body can be dealt with.

The above valve core forms are only representative of a plurality of valve cores, and other more possible valve cores are not described in detail here.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.