CN110761965A

CN110761965A - Micro-flow pump

Info

Publication number: CN110761965A
Application number: CN201911265966.7A
Authority: CN
Inventors: 王伯冰; 王璟睿
Original assignee: WEIFANG JUDE ELECTRONICS Co Ltd
Current assignee: WEIFANG JUDE ELECTRONICS Co Ltd
Priority date: 2019-12-11
Filing date: 2019-12-11
Publication date: 2020-02-07

Abstract

The invention provides a micro-flow pump, a shell component; a piezoelectric actuation assembly located within the housing assembly, the piezoelectric actuation assembly comprising: the free part is movably connected with the shell assembly; the fixing part is connected with the shell component; the first piston assembly is positioned in the shell assembly and is movably connected with the shell assembly; a first displacement transmission assembly, the first displacement transmission assembly comprising: one end of the first connecting piece is hinged with the free part, and the other end of the first connecting piece is hinged with the first piston assembly; and one end of the second connecting piece is hinged with the fixing part, and the other end of the second connecting piece is hinged with the first piston assembly. The micro-flow pump provided by the invention can reduce the moving stroke, thereby realizing more precise and accurate micro-flow control and improving the control precision of the micro-flow pump provided by the invention.

Description

Micro-flow pump

Technical Field

The invention belongs to the field of micro-flow control equipment, and particularly relates to a micro-flow pump.

Background

In the fields of medicine, chemical engineering, bioengineering, electronic engineering, and the like, a micro-flow pump is generally used to realize precise control of micro-flow.

The existing micro-flow pump includes a housing, a linear motor, a piston, and a check valve. The linear motor is located the casing, and the piston is located the casing, and the diaphragm is connected with casing relative movement, and the check valve sets up on the casing. When the micro-flow pump works, the motor is electrified to act, the piston reciprocates in the shell under the driving of the motor to compress or stretch air in the shell, and drainage or water pumping is carried out under the action of the one-way valve.

However, in the conventional micro-flow pump, the linear motor is used as a drive, and the minimum movement amount of the piston is directly limited by the limit of the minimum operation stroke of the linear motor, so that more precise and accurate micro-flow control cannot be realized.

Disclosure of Invention

The invention provides a micro-flow pump, which can realize output of smaller displacement and more accurate micro-flow control, aiming at the technical problem that the existing micro-flow pump can not realize more precise and accurate micro-flow control. In order to achieve the purpose, the invention adopts the following technical scheme:

a micro-flow pump comprising:

a housing assembly;

a piezoelectric actuation assembly located within the housing assembly, the piezoelectric actuation assembly comprising:

a free portion movably interconnected with the housing assembly;

a fixed portion connected with the housing assembly, the free portion being movable relative to the fixed portion;

a first piston assembly located within the housing assembly, the first piston assembly being movably connected with the housing assembly;

a first displacement transmission assembly, the first displacement transmission assembly comprising:

one end of the first connecting piece is hinged with the free part, the other end of the first connecting piece is hinged with the first piston assembly, and the included angle between the first connecting piece and the horizontal plane is 50-75 degrees.

Further, the first displacement transmission assembly further comprises:

one end of the second connecting piece is hinged with the fixing part, the other end of the second connecting piece is hinged with the first piston assembly, and the included angle between the second connecting piece and the horizontal plane is 50-75 degrees.

Further, the first piston assembly includes:

the piston body is connected with the shell assembly in a relatively moving way;

the first sliding piece and the piston body are mutually movably connected along the moving direction of the free part, and the other end of the first sliding piece and the other end of the first connecting piece are mutually hinged;

the second sliding piece and the piston body are mutually movably connected along the moving direction of the free part, and the second sliding piece is mutually hinged with the other end of the second connecting piece;

the shell assembly is provided with a first guide part, the first guide part is arranged on the shell assembly, the third connecting piece is movably connected with the shell assembly through the first guide part, and the third connecting piece is connected with the first sliding piece and the second sliding piece.

Further, the piston assembly further comprises:

the second guide part is arranged in the shell assembly, the second guide part is opposite to the first guide part and is arranged in parallel, the third sliding part is connected with the shell assembly in a relatively moving mode through the second guide part, the third connecting piece is connected with the third sliding part in a relatively rotating mode, and the third connecting piece is respectively in threaded connection with the first sliding part and the second sliding part.

Further, the threaded connection between the third connecting piece and the first sliding piece and the threaded connection between the third connecting piece and the second sliding piece are opposite in rotation direction.

Further, still include:

the second piston assembly is the same as the first piston assembly in structure, the second piston assembly is positioned in the shell assembly, the second piston is positioned on one side of the piezoelectric actuating assembly, the second piston assembly is opposite to the first piston assembly, and the second piston is in relative moving connection with the shell assembly;

the second displacement transmission assembly is of the same structure as the first displacement transmission assembly, the second displacement transmission assembly is located in the shell assembly and located on one side of the piezoelectric actuating assembly, the second displacement transmission assembly and the first displacement transmission assembly are arranged oppositely, the second displacement transmission assembly and the piezoelectric actuating assembly are hinged to each other, and the second displacement transmission assembly and the second piston assembly are hinged to each other.

Further, still include:

the end cover assembly is connected with the shell assembly, a cavity is formed by the end cover assembly, the shell assembly and the first piston assembly, and a one-way inlet valve and a one-way outlet valve are arranged on the end cover assembly.

Further, a first stepped hole is formed in the end cover assembly and penetrates through the end cover assembly;

the one-way inlet valve comprises:

a first connection part connected to the first stepped hole;

a first closing part covering the first stepped hole;

the first connecting part is connected with the first sealing part through the first deformation part.

Furthermore, a second stepped hole is formed in the end cover assembly, the second stepped hole penetrates through the end cover assembly, and the direction of the second stepped hole is opposite to that of the first stepped hole;

the one-way outlet valve includes:

a second connection part connected to the second stepped hole;

a second closing part covering the second stepped hole;

a second deformation part through which the second connection part connects the second closing part.

Further, the one-way inlet valve and the one-way outlet valve are made of rubber materials.

Compared with the prior art, the invention has the beneficial effects that:

1. the micro-flow pump provided by the invention is provided with a first displacement transmission assembly, wherein the first displacement transmission assembly comprises a first connecting piece, and the first connecting piece is respectively hinged with the first piston assembly and the free part of the piezoelectric actuating assembly. When the piezoelectric actuating assembly is electrified to move, the free portion moves relative to the shell assembly so as to drive the first connecting piece to rotate, the first connecting piece rotates relative to the first piston assembly, and meanwhile, the first connecting piece drives the first piston assembly to move relative to the shell assembly. The movement stroke of the free part of the piezoelectric actuating assembly is transmitted to the first piston assembly through the first connecting piece, and the movement stroke of the free part of the piezoelectric actuating assembly is amplified, so that finer and more accurate micro-flow control is realized, and the control precision of the micro-flow pump provided by the invention is improved.

2. The micro-flow pump provided by the invention is provided with a first sliding piece, a second sliding piece, a third connecting piece and a third sliding piece, wherein the first sliding piece and the second sliding piece are connected with a first piston assembly in a relatively movable mode, the third connecting piece is connected with a shell assembly in a relatively movable mode, the third sliding piece is connected with the shell assembly in a relatively movable mode, the third connecting piece is connected with the third sliding piece in a relatively rotatable mode, and the third connecting piece is respectively connected with the first sliding piece and the second sliding piece in a threaded mode. The third connecting piece is rotated, the first sliding piece and the second sliding piece move relative to the third connecting piece under the effect of threaded connection, the distance between the first sliding piece and the second sliding piece can be changed, and the displacement amplification factor of the first displacement transmission assembly is further adjusted, so that different micro displacements can be controlled, and more accurate micro flow control can be realized.

3. The micro-flow pump provided by the invention is also provided with the second piston assembly and the second displacement transmission assembly to form a symmetrical displacement transmission structure, can generate two output displacements under the displacement input of the same piezoelectric actuating assembly, and can adjust the amplification factors of the two displacements respectively to realize different displacement outputs, thereby further simplifying the mechanical structure and improving the utilization rate of the piezoelectric actuating assembly.

Drawings

Fig. 1 is a schematic structural diagram of a micro flow pump provided in this embodiment;

FIG. 2 is a schematic view of the interior of the housing assembly of FIG. 1;

FIG. 3 is a schematic cross-sectional view of the micro-flow pump of FIG. 1;

FIG. 4 is a schematic cross-sectional front view of the first housing of FIG. 3;

fig. 5 is a schematic structural view of the piezoelectric actuator of fig. 3;

FIG. 6 is a schematic view of the one-way inlet valve of FIG. 3;

FIG. 7 is a schematic diagram of the process of fluid entering the micro-flow pump;

FIG. 8 is a schematic diagram of the process of fluid flow out of the microfluidic pump;

FIG. 9 is a simplified diagram of the micro-flow pump of FIG. 1;

FIG. 10 is a simplified diagram of the micro-flow pump of FIG. 1;

fig. 11 is a graph of α as a function of displacement magnification C.

The reference numerals are explained in detail:

1. a housing assembly; 11. a first housing; 111. a rectangular groove; 12. a second housing; 121. a first guide portion; 122. a second guide portion; 123. a flange face; 13. a third housing;

2. a piezoelectric actuation assembly; 21. a piezoelectric actuator; 211. a fixed part; 212. a free portion; 213. a hinge portion;

3. a first piston assembly; 31. a piston body; 311. a third guide portion; 32. a first slider; 33. a second slider; 34. a third connecting member; 35. a third slider;

4. a second piston assembly;

5. a first displacement transmission assembly; 51. a first connecting member; 52. a second connecting member;

6. a second displacement transmission assembly;

7. an end cap assembly; 71. a first stepped hole; 711. a first step surface; 72. a second stepped bore; 73. a one-way inlet valve; 731. a first connection portion; 732. a first closing portion; 733. a first deformation section; 74. a one-way outlet valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be fully described in detail below with reference to the accompanying drawings. It is obvious that the described embodiments are only some specific embodiments, not all embodiments, of the general technical solution of the present invention. All other embodiments, which can be derived by a person skilled in the art from the general idea of the invention, fall within the scope of protection of the invention.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

The terms "first", "second" and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", "third" may explicitly or implicitly include one or more of the features.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The invention provides a micro-flow pump, which can realize output of smaller displacement and more accurate micro-flow control, aiming at the technical problem that the existing micro-flow pump can not realize more precise and accurate micro-flow control. The technical solution of the present invention will be specifically described with reference to specific examples.

A micro-flow pump comprising:

a housing assembly 1;

a piezoelectric actuating assembly 2, the piezoelectric actuating assembly 2 being located within the housing assembly 1, the piezoelectric actuating assembly 2 comprising:

a free part 212, wherein the free part 212 is movably connected with the shell component 1;

a fixed part 211, the fixed part 211 being connected to the housing assembly 1, the free part 212 being movable relative to the fixed part 211;

the first piston assembly 3 is positioned in the shell assembly 1, and the first piston assembly 3 is movably connected with the shell assembly 1;

a first displacement transmission member 5, the first displacement transmission member 5 comprising:

one end of the first connecting piece 51 is hinged with the free part 212, the other end of the first connecting piece 51 is hinged with the first piston assembly 3, and the included angle between the first connecting piece 51 and the horizontal plane is 50-75 degrees.

The micro-flow pump of the present embodiment is provided with a first displacement transmission assembly 5, wherein the first displacement transmission assembly 5 includes a first connector 51, and the first connector 51 is hinged to the first piston assembly 3 and the free portion 212 of the piezoelectric actuator assembly 2. When the piezoelectric actuating assembly 2 is powered on to move, the free portion 212 moves relative to the housing assembly 1, so as to drive the first connecting member 51 to rotate relative to the piezoelectric actuating assembly 2, the first connecting member 51 rotates relative to the first piston assembly 3, and meanwhile, the first connecting member 51 drives the first piston assembly 3 to move along the inside of the housing assembly 1. The moving stroke of the free part 212 of the piezoelectric actuating assembly 2 is transmitted to the first piston assembly 3 through the first connecting member 51, and the moving stroke of the free part 212 of the piezoelectric actuating assembly 2 is amplified, so that finer and more accurate micro-flow control is realized, and the control precision of the micro-flow pump provided by the embodiment is improved.

To facilitate understanding of the technical solution of the present invention, the micro flow pump provided in this embodiment will now be specifically described in the process of amplifying the displacement.

Referring to fig. 9, which is a simplified diagram of the structure of the micro-fluid pump according to the present embodiment, a fixing portion 211 of a piezoelectric actuating assembly 2 is fixedly connected in a housing assembly 1, a free portion 212 of the piezoelectric actuating assembly 2 moves along the housing assembly 1 in a vertical direction, a length of the free portion 212 is B, a displacement of the free portion 212 is a, two ends of a first connecting member 51 are respectively hinged to the free portion 212 and a first piston assembly 3, a length of the first connecting member 51 is L, an included angle between the first connecting member 51 and the vertical direction is α, a length of the first piston assembly 3 is h, and a moving distance of the first piston assembly 3 along the housing assembly 1 is B, when the piezoelectric actuating assembly 2 is powered on, the free portion 212 generates a displacement a along the vertical direction relative to the fixing portion 211, the first connecting member 51 is driven to rotate relative to the free portion 212 and the fixing portion 211, and at the same time, the first connecting member 51 drives the first piston assembly 3 to generate a displacement B along the housing assembly 1.

Referring to fig. 10, the displacement transmission process of the micro flow pump according to the present embodiment is further simplified, the length L of the first connecting member 51 is not changed, the included angle between the first connecting member 51 and the horizontal plane is α before the movement, the included angle between the first connecting member 51 and the horizontal plane is α' after the movement, the displacement of the free portion 212, i.e., the input displacement, is a, the displacement of the first piston assembly 3, i.e., the output displacement, is B, and the relationship between a and B is:

the relationship between the output displacement B and the input displacement A, i.e. the relationship can be obtained from equation (1)

In the formula (2), C is the displacement transmission coefficient of the micro-flow pump provided in this embodiment. Further from equation (2) can be derived

Referring to fig. 11, which is a graph of C as a function of α, it is apparent that when the angle α is greater than 45 ° and the value of C is greater than 1, the first displacement transmission assembly 5 amplifies the displacement a of the free portion 212 of the piezoelectric braking assembly 2. preferably, when the angle α is in the range of 50 ° to 75 °, the value of the amplification factor C changes monotonically and the amplification factor C and α have a nearly linear amplification relationship, which is beneficial to the control of the amplification factor and further improves the flow control accuracy of the micro-flow pump.

Typically, the output displacement of the prior art piezoelectric actuator assembly 2 is on the order of hundreds of microns (100 μm). The micro-flow pump provided by the embodiment can realize displacement output of hundred micrometers and millimeter (mm) level by the minimum output displacement through the displacement amplification effect of the first displacement transmission component 5. Compared with the prior micro-flow pump which adopts a motor as a displacement output mechanism and can only output micro-flow at millimeter level, the micro-flow pump can realize smaller output displacement and further realize finer micro-flow control.

The specific structure of the micro flow pump provided in this embodiment will be further described in detail.

Referring to fig. 1 to 3, the micro-flow pump provided in this embodiment includes a housing assembly 1, a piezoelectric actuator assembly 2, a first piston assembly 3, a second piston assembly 4, a first displacement transmission assembly 5, a second displacement transmission assembly 6, and an end cap assembly 7. The piezoelectric actuating assembly 2 is positioned in the shell assembly 1, the first piston assembly 3 and the second piston assembly 4 are positioned in the shell assembly 1, and the first piston assembly 3 and the second piston assembly 4 are connected with the shell assembly 1 in a relatively movable mode. The first displacement transmission assembly 5 is positioned between the piezoelectric actuating assembly 2 and the first piston assembly 3, and the first displacement transmission assembly 5 is hinged with the piezoelectric actuating assembly 2 and the first piston assembly 3 respectively. The second displacement transmission assembly 6 is positioned between the piezoelectric actuating assembly 2 and the second piston assembly 4, and the second displacement transmission assembly 6 is hinged with the piezoelectric actuating assembly 2 and the second piston assembly 4 respectively. The end cap assembly 7 is attached to both ends of the housing assembly 1.

Referring to fig. 3 and 4, the housing assembly 1 includes a first housing 11 and a second housing 12. The second housing 12 and the third housing 13 are respectively attached to both sides of the first housing 11. The first housing 11 is used for accommodating the piezoelectric actuating assembly 2, and the piezoelectric actuating assembly 2 is connected to the inside of the first housing 11. A rectangular groove 111 is formed in the upper portion inside the first housing 11, the piezoelectric actuation assembly 2 is connected in the rectangular groove 111 through a pin shaft, and the pin shaft moves in the rectangular groove 111, so that the piezoelectric actuation assembly 2 moves along the rectangular groove 111, and the piezoelectric actuation assembly 2 is guided to move. The second housing 12 is used for accommodating the first piston assembly 3, the second housing 12 is connected with the first housing 11, and the first piston assembly 3 is positioned in the second housing 12 and is connected with the second housing 12 in a relatively movable manner, preferably in a sealing movable manner. The first piston assembly 3 is capable of reciprocating along the inner wall of the second housing 12. The second housing 12 is provided with a first guide portion 121, the first guide portion 121 is a rectangular through hole which is arranged above the second housing 12 and penetrates through the second housing 12, the first piston assembly 3 is connected with the first guide portion 121, the first guide portion 121 limits the moving direction of the first piston assembly 3, rotation of the first piston assembly 3 in the moving process is avoided, and the accuracy of position movement of the first piston assembly 3 is improved. The end cover assembly 7 is connected to one end of the second housing 12 far away from the first housing 11, and the end cover assembly 7 forms a fluid accommodating cavity together with the second housing 12 and the first piston assembly 3, so that fluid can flow in and out.

The piezoelectric actuator assembly 2 provides a driving force for the movement of the first piston assembly 3, enabling the first piston assembly 3 to reciprocate within the housing assembly 1, thereby enabling the fluid to flow in and out of the receiving chamber. The piezoelectric actuating assembly 2 may preferably be an existing piezoelectric actuator 21. Specifically, referring to fig. 5, the piezoelectric actuator assembly 2 includes a free portion 212, a fixed portion 211, and a hinge portion 213, and the free portion 212 is movable relative to the fixed portion 211. The fixing portion 211 is connected to an inner bottom surface of the first housing 11. The free portion 212 is movably connected to the rectangular groove 111 of the first housing 11 by a pin, and the pin moves in the rectangular groove 111, so that the free portion 212 moves linearly along the rectangular groove 111, and further guides the moving direction of the piezoelectric actuator assembly 2. The hinge 213 is used for hinging with the first displacement transmission component 5.

Referring to fig. 2 and 3, the first piston assembly 3 is located within the housing assembly 1, the first piston assembly 3 being movably connected to the housing assembly 1. Specifically, the first piston assembly 3 includes a piston body 31, a first slider 32, a second slider 33, a third link 34, and a third slider 35. The piston body 31 is located in the second housing 12, and the piston body 31 is movably connected, preferably hermetically, to the inner wall of the second housing 12, so as to prevent the micro-flow pump provided in this embodiment from leaking. The piston body 31 is provided with a third guide portion 311, and the third guide portion 311 may be a dovetail groove or a T-shaped groove structure, and plays a role of guiding and connecting the first sliding member 32 and the second sliding member 33. Specifically, each of the first slider 32 and the second slider 33 is provided with a dovetail structure or a T-shaped structure engaged with the third guide portion 311, and the first slider 32 and the second slider 33 are respectively connected to the third guide portion 311, so that when an external force is applied, the first slider 32 and the second slider 33 can be moved along the third guide portion 311, thereby adjusting the distance between the first slider 32 and the second slider 33. The third connecting member 34 is connected to the first sliding member 32 and the second sliding member 33, the third connecting member 34 is movably connected to the first guiding portion 121 of the second housing 12, that is, the third connecting member 34 can move along the first guiding portion 121, so as to drive the first sliding member 32 and the second sliding member 33 to move along the first guiding portion 121, and further drive the piston body 31 to move along the first guiding portion 121, which can guide the movement of the piston body 31, so that the movement of the first piston assembly 3 is more stable, and the flow rate control of the micro flow pump provided in this embodiment is more stable.

The first displacement transmission assembly 5 amplifies the displacement of the piezoelectric actuator assembly 2, specifically, referring to fig. 2 and 3, the first displacement transmission assembly 5 includes a first connecting member 51, one end of the first connecting member 51 is hinged to a free portion 212 of the piezoelectric actuator assembly 2, and the other end of the first connecting member 51 is hinged to the first piston assembly 3, and more specifically, to the first sliding member 32, the length of the first connecting member 51 is determined by an included angle α between the first connecting member 51 and the horizontal plane, preferably, α to 75 °, as mentioned above, when the piezoelectric actuator assembly 2 is electrically moved, the free portion 212 is moved, so as to rotate the first connecting member 51 in the space of the housing assembly 1, the first connecting member 51 further drives the first sliding member 32 to move along the direction of the first guide portion 121, so as to drive the piston body 31 to move along the inner wall of the second housing 12, so as to realize micro-flow control, the input displacement a of the free portion 212 is converted into the output displacement B of the piston body 31 through the first displacement transmission assembly 5, so as to realize displacement amplification.

Preferably, in order to improve the moving smoothness of the piston body 31, in the micro-flow pump provided by the present embodiment, the first displacement transmission assembly 5 further includes a second connector 52. One end of the second connecting piece 52 is hinged with the fixing part 211, the other end of the second connecting piece 52 is hinged with the piston body 31, and the included angle between the second connecting piece 52 and the horizontal plane is 50-75 degrees. The second link 52 moves in the same manner as the first link 51. The second connecting piece 52 and the first connecting piece 51 are symmetrically arranged, so that the motion stability of the first piston assembly 3 is improved.

In the micro flow pump provided by the embodiment, in order to realize the adjustable displacement magnification C of the first displacement transmission assembly 5, the distance between the first slider 32 and the second slider 33 is adjusted through the third connecting piece 34, so that the included angle α between the first connecting piece 51 and the second connecting piece 52 and the horizontal plane is adjusted, so that the adjustment of the displacement magnification C is realized, specifically, the first piston assembly 3 further comprises a third slider 35, a second guide part 122 is arranged below the inside of the second housing 12, the second guide part 122 is arranged opposite to the first guide part 121 and is parallel to each other, the third slider 35 is connected into the second guide part 122, the third slider 35 moves linearly along the second guide part 122, the third connecting piece 34 is respectively in threaded connection with the first slider 32 and the second slider 33, one end of the third connecting piece 34 extends out of the first guide part 121, the other end of the third connecting piece 34 is in rotational connection with the third slider 35, for example, the rotational connection can be realized through a bearing 351, the adjustment of the threaded connection between the third connecting piece 34 and the first slider 32 can be realized through the adjustment of the threaded connection between the first slider 32 and the second slider 34, so that the adjustment of the threaded connection between the slider 32 and the slider 34 and the included angle α can be adjusted, so that the adjustment of the relative movement magnification C can be realized through the adjustment of the third slider 34 and the relative to the slider 32, so that the relative movement magnification of the slider 32 can be realized through the relative to the longitudinal adjustment of the slider 34, so that the relative movement magnification of the slider 32, the slider 34, the relative to be realized through the relative movement of the relative to be adjusted, the relative movement magnification C, the relative movement of the slider 34, the slider 32 and the relative movement of the relative to be preferably, so that the relative to be further adjustment of the relative to.

The micro-flow pump provided by the embodiment further comprises an end cover assembly 7, the end cover assembly 7 is connected with the housing assembly 1, the end cover assembly 7, the housing assembly 1 and the first piston assembly 3 form a cavity, and the end cover assembly 7 is provided with a one-way inlet valve 73 and a one-way outlet valve 74. Specifically, the end of the second housing 12 remote from the first housing 11 is provided with a flange face 123, and the end cap assembly 7 is attached to the flange face 123. The end cap assembly 7 forms a cavity with the second housing 12 and the piston body 31 for ingress and egress of micro-fluids. More specifically, the end cap assembly 7 is provided with a first stepped hole 71 and a second stepped hole 72 penetrating the end cap assembly 7, and the direction of the second stepped hole 72 is opposite to the direction of the first stepped hole 71. The first step hole 71 has a first step surface 711, and the one-way inlet valve 73 is mounted on the first step surface 711. The one-way inlet valve 73 includes a first connection portion 731, a first closing portion 732, and a first deformation portion 733, the first connection portion 731 is located in the first step surface 711, the first closing portion 732 covers the first step hole 71, and the first deformation portion 733 connects the first connection portion 731 and the first closing portion 732. The second step bore 72 has a second step surface on which a one-way outlet valve 74 is mounted. The one-way outlet valve 74 includes a second connecting portion located in the second stepped surface, a second closing portion covering the second stepped hole 72, and a second deformation portion connecting the second connecting portion and the second closing portion.

Referring to fig. 7 and 8, when the piezoelectric braking assembly 2 is powered on, when the free portion 212 moves upwards, the first connecting member 51 and the second connecting member 52 are driven to rotate, so that the first sliding member 32 and the second sliding member 33 drive the piston body 31 to move towards the piezoelectric braking assembly 2, so that the pressure in the cavity is reduced, external liquid or gas pushes the first sealing portion 732 of the one-way inlet valve 73, the first deformation portion 733 is deformed, so that the first sealing portion 732 is far away from the first stepped hole 71, and the first stepped hole 71 is released from being sealed, and the one-way outlet valve 74 and the one-way inlet valve 73 are opposite in direction, so that the second sealing portion is tightly attached to the second stepped hole 72, so that external gas or liquid can only enter the cavity through the one-way inlet valve 73; contrary to the above process, when the piezoelectric braking assembly 2 is powered on, and the free portion 212 moves downward, the first connecting member 51 and the second connecting member 52 are driven to rotate, so that the first sliding member 32 and the second sliding member 33 drive the piston body 31 to move in a direction away from the piezoelectric braking assembly 2, so that the pressure inside the cavity is increased, the liquid or gas inside the cavity pushes the second sealing portion of the one-way outlet valve 74, the second deforming portion deforms, so that the second sealing portion is away from the second stepped hole 72, the sealing of the second stepped hole 72 is released, the direction of the one-way inlet valve 73 is opposite to that of the one-way outlet valve 74, so that the first sealing portion 732 clings to the first stepped hole 71, and the gas or liquid inside the cavity can only flow out of the cavity through the one-way outlet valve 74.

Preferably, the one-way inlet valve 73 and the one-way outlet valve 74 are of a rubber material.

The micro flow pump provided in this embodiment further includes a second piston assembly 4 and a second displacement transmission assembly 6, and the housing assembly 1 further includes a third housing 13. Can form symmetrical displacement transmission structure, can produce two output displacements under the displacement input of same piezoelectricity actuating assembly 2, can adjust two displacement magnification C respectively simultaneously, realize different displacement output, further simplify mechanical structure, improve piezoelectricity actuating assembly 2's utilization ratio. Specifically, the housing assembly 1 further includes a third housing 13, the second piston assembly 4 has the same structure as the first piston assembly 3, the second piston assembly 4 and the first piston assembly 3 are symmetrically installed in the third housing 13, and the second piston assembly 4 and the third housing 13 are movably connected to each other. The second displacement transmission assembly 6 has the same structure as the first displacement transmission assembly 5, the second displacement transmission assembly 6 is positioned in the third shell 13, the second displacement transmission assembly 6 is positioned on one side of the piezoelectric actuating assembly 2, the second displacement transmission assembly 6 is opposite to the first displacement transmission assembly 5, the second displacement transmission assembly 6 is hinged with the piezoelectric actuating assembly 2, and the second displacement transmission assembly 6 is hinged with the second piston assembly 4. When the piezoelectric actuating component 2 is powered on, the free portion 212 simultaneously drives the first displacement transmission component 5 and the second displacement transmission component 6 to rotate in the housing component 1, so as to drive the first piston component 3 and the second piston component 4 to move in the second housing 12 and the third housing 13, thereby simultaneously realizing micro-flow control of two cavities.

Further, the distance between the first sliding part 32 and the second sliding part 33 in the first piston assembly 3 and the distance between the first sliding part 32 and the second sliding part 33 in the second piston assembly 4 can be different from each other by rotating the third connecting part 34 in the first piston assembly 3 and the second piston assembly 4 respectively, so that the displacement amplification factor C of the first displacement transmission assembly 5 and the second displacement transmission assembly 6 is different, and therefore, two different displacement outputs can be realized under the same displacement, and different flow control can be realized.

Claims

1. A micro-flow pump, comprising:

a housing assembly;

a free portion movably interconnected with the housing assembly;

2. The micro-fluidic pump of claim 1 wherein the first displacement transfer assembly further comprises:

3. The micro-fluidic pump of claim 2 wherein the first piston assembly comprises:

4. The micro-fluidic pump of claim 2 wherein the piston assembly further comprises:

5. The micro-flow pump of claim 4, wherein the threaded connection between the third connector and the first slide and the threaded connection between the third connector and the second slide are of opposite hand.

6. The micro-flow pump as claimed in any one of claims 1 to 5, further comprising:

7. The micro-flow pump as claimed in any one of claims 1 to 5, further comprising:

8. The micro-flow pump of claim 7, wherein the end cap assembly is provided with a first stepped bore therethrough;